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21 pages, 2345 KiB  
Article
Unlocking Consumer Preferences: Sensory Descriptors Driving Greek Yogurt Acceptance and Innovation
by Helena Maria Andre Bolini, Flavio Cardello, Alessandra Cazellatto de Medeiros and Howard Moskowitz
Foods 2025, 14(1), 130; https://doi.org/10.3390/foods14010130 - 5 Jan 2025
Viewed by 1100
Abstract
Greek yogurt, a traditional food with roots in Ancient Greece, Mesopotamia, and Central Asia, has become a dietary staple worldwide due to its creamy texture, distinct flavor, and rich nutritional profile. The contemporary emphasis on health and wellness has elevated Greek yogurt as [...] Read more.
Greek yogurt, a traditional food with roots in Ancient Greece, Mesopotamia, and Central Asia, has become a dietary staple worldwide due to its creamy texture, distinct flavor, and rich nutritional profile. The contemporary emphasis on health and wellness has elevated Greek yogurt as a functional food, recognized for its high protein content and bioavailable probiotics that support overall health. This study investigates the sensory attributes evaluated by a panel of 22 trained assessors and the consumer preferences driving the acceptance of Greek yogurt formulations. Samples with higher consumer acceptance were characterized by sensory attributes such as “high texture in the mouth, surface uniformity, creaminess, apparent homogeneity, mouth-filling, grip in the mouth, ease of pick-up with a spoon, milk cream flavor, sweetness, and dairy flavor” (Tukey’s test, p < 0.05). These attributes strongly correlated with consumer preferences, underscoring their importance in product optimization. The findings provide a framework for refining Greek yogurt formulations to address diverse market demands, achieving a balance between sensory excellence and practical formulation strategies. This research reinforces the significance of Greek yogurt as a culturally adaptable, health-promoting dietary component and a promising market segment for ongoing innovation. Full article
(This article belongs to the Special Issue Flavor, Palatability, and Consumer Acceptance of Foods)
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<p>Dendrogram two-way (descriptive sensory terms and yogurt samples) obtained through hierarchical cluster analysis using the Ward method algorithm and the Euclidean distance similarity index. Representative clusters of descriptive terms to Greek yogurt.</p>
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<p>Acceptance of Greek yogurts about appearance, consistency in the spoon, flavor, texture, and overall impression.</p>
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<p>External preference mapping was obtained by partial least-squares regression of the descriptive sensory profile and consumers’ overall impressions of Greek yogurt. (diamond = Greek yogurt samples; blue points = consumers; red points = quantitative descriptive analysis attributes). The partial least-square regression used the individual notes of consumers for overall impression.</p>
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<p>Partial least-squares standardized coefficients of Greek yogurt (green = descriptor terms that contribute positively to consumer acceptance; blue = descriptive terms that did not significantly contribute to consumer acceptance; red = descriptor terms that contribute negatively to consumer acceptance) at 95% confidence interval. The partial least-square regression used the average consumer notes for overall impression.</p>
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<p>Consumer purchase intention regarding the Greek yogurt samples.</p>
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23 pages, 5729 KiB  
Article
Estimation of Ecological Water Requirement and Water Replenishment Regulation of the Momoge Wetland
by Hongxu Meng, Xin Zhong, Yanfeng Wu, Xiaojun Peng, Zhijun Li and Zhongyuan Wang
Water 2025, 17(1), 114; https://doi.org/10.3390/w17010114 - 3 Jan 2025
Viewed by 671
Abstract
Ensuring the ecological water requirements (EWR) suitable for wetlands are upheld is essential for maintaining the stability and health of their ecosystems, a challenge faced by wetlands globally. However, previous studies on EWRs estimation lack a comprehensive consideration of wetlands and still suffer [...] Read more.
Ensuring the ecological water requirements (EWR) suitable for wetlands are upheld is essential for maintaining the stability and health of their ecosystems, a challenge faced by wetlands globally. However, previous studies on EWRs estimation lack a comprehensive consideration of wetlands and still suffer from the problem of rough time scales. Prior studies have predominantly concentrated on its core and buffer zones, neglecting a comprehensive analysis of the wetland’s entirety and failing to account for the seasonal variations in EWRs. To fill this gap, we proposed a novel framework for estimating EWRs wetland’s entirety to guide the development of dynamic water replenishment strategies. The grey prediction model was used to project the wetland area under different scenarios and designed water replenishment strategies. We then applied this framework in a key wetland conservation area in China, the Momoge Wetland, which is currently facing issues of areal shrinkage and functional degradation due to insufficient EWRs. Our findings indicate that the maximum, optimal, and minimum EWRs for the Momoge Wetland are 24.14 × 108 m3, 16.65 × 108 m3, and 10.88 × 108 m3, respectively. The EWRs during the overwintering, breeding, and flood periods are estimated at 1.92 × 108 m3, 5.39 × 108 m3, and 8.73 × 108 m3, respectively. Based on the predicted wetland areas under different climatic conditions, the necessary water replenishment volumes for the Momoge Wetland under scenarios of dry-dry-dry, dry-dry-normal, dry-normal-dry, and normal-normal-normal are calculated to be 0.70 × 108 m3, 0.49 × 108 m3, 0.68 × 108 m3, and 0.36 × 108 m3, respectively. In years characterized by drought, the current water replenishment projects are inadequate to meet the wetland’s water needs, highlighting the urgent need for the implementation of multi-source water replenishment techniques to enhance the effectiveness of these interventions. The results of this study provide insights for annual and seasonal water replenishment planning and multi-source water management of wetlands with similar problems as the Momoge Wetland. With these new insights, our novel framework not only advances knowledge on the accuracy of wetland ecological water requirement assessment but also provides a scalable solution for global wetland water resource management, helping to improve the ecosystem’s adaptability to future climate changes. Full article
(This article belongs to the Special Issue Wetland Conservation and Ecological Restoration)
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<p>River networks, nature reserve zonation (<b>a</b>), and land use types (<b>b</b>) in the Momoge Wetland.</p>
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<p>Annual suitable ecological water requirements and threshold of target (<b>a</b>) and indicator (<b>b</b>) level in the Momoge Wetland. Target ecological water requirements refer to maintaining the wetland’s scale, promoting the conservation of biodiversity, and stability of the ecosystem’s functions and structure. Indicators of ecological water requirements refer to evapotranspiration water requirement of wetland, soil water requirement, vegetation water requirement, habitat water requirement, and water requirement for groundwater recharge.</p>
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<p>Seasonal suitable ecological water requirement and threshold of target (<b>a</b>) and indicator (<b>b</b>) in the Momoge Wetland. Target ecological water requirements refer to maintaining the wetland’s scale, promoting the conservation of biodiversity, and the stability of the ecosystem’s functions and structure. Indicators of ecological water requirements refer to evapotranspiration water requirements of wetland, soil water requirements, vegetation water requirements, habitat water requirements, and water requirements for groundwater recharge.</p>
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<p>The maximum (<b>a</b>), suitable (<b>b</b>), and minimum (<b>c</b>) ecological water requirements for the wetland runoff seasons of Momoge Wetland in 1979 and 1998. The overwintering period, breeding period, and flood period refer to November to March of the following year, April to June, and July to October, respectively.</p>
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22 pages, 13566 KiB  
Article
Exploring Architectural Units Through Robotic 3D Concrete Printing of Space-Filling Geometries
by Meryem N. Yabanigül and Derya Gulec Ozer
Buildings 2025, 15(1), 60; https://doi.org/10.3390/buildings15010060 - 27 Dec 2024
Viewed by 762
Abstract
The integration of 3D concrete printing (3DCP) into architectural design and production offers a solution to challenges in the construction industry. This technology presents benefits such as mass customization, waste reduction, and support for complex designs. However, its adoption in construction faces various [...] Read more.
The integration of 3D concrete printing (3DCP) into architectural design and production offers a solution to challenges in the construction industry. This technology presents benefits such as mass customization, waste reduction, and support for complex designs. However, its adoption in construction faces various limitations, including technical, logistical, and legal barriers. This study provides insights relevant to architecture, engineering, and construction practices, guiding future developments in the field. The methodology involves fabricating closed architectural units using 3DCP, emphasizing space-filling geometries and ensuring structural strength. Across three production trials, iterative improvements were made, revealing challenges and insights into design optimization and fabrication techniques. Prioritizing controlled filling of the unit’s internal volume ensures portability and ease of assembly. Leveraging 3D robotic concrete printing technology enables precise fabrication of closed units with controlled voids, enhancing speed and accuracy in production. Experimentation with varying unit sizes and internal support mechanisms, such as sand infill and central supports, enhances performance and viability, addressing geometric capabilities and fabrication efficiency. Among these strategies, sand filling has emerged as an effective solution for internal support as it reduces unit weight, simplifies fabrication, and maintains structural integrity. This approach highlights the potential of lightweight and adaptable modular constructions in the use of 3DCP technologies for architectural applications. Full article
(This article belongs to the Special Issue Robotics, Automation and Digitization in Construction)
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<p>(<b>a</b>) Bisymmetric Hendecahedron unit; (<b>b</b>) assembly method of the unit without gaps; (<b>c</b>) space-filling ability of the unit through geometry and assembly method (credit to authors).</p>
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<p>Three-dimensional concrete printing setup (credit to authors).</p>
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<p>Six-axis Kuka KR 210-L150 robotic arm (credit to authors).</p>
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<p>Production positions of the whole- and half-units (credit to authors).</p>
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<p>(<b>a</b>) Bisymmetric Hendecahedron top view; (<b>b</b>) material spread; (<b>c</b>) continuous production path; (<b>d</b>) distortion in the form (credit to authors).</p>
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<p>Bisymmetric Hendecahedron whole- and half-unit printing path designs and infill geometries (credit to authors).</p>
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<p>Simulation of fabrication and assembly of half-unit (credit to authors).</p>
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<p>The production process of the first trial (credit to authors).</p>
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<p>Digital model (<b>above</b>) and physical prototype (<b>below</b>) of the first trial (credit to authors).</p>
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<p>The infill structure detail of the first trial (credit to authors).</p>
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<p>Production process and infill structure of the unit during the second trial (credit to authors).</p>
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<p>Deformation due to insufficient support on the upper surfaces (credit to authors).</p>
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<p>Digital model and physical prototype of the second trial (credit to authors).</p>
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<p>Production process and infill structure of the second unit production trial (credit to authors).</p>
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<p>Deformation due to insufficient sand-filling support on the upper surfaces and sand between layers (credit to authors).</p>
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<p>Digital model (<b>above</b>) and physical prototype (<b>below</b>) of the third trial (credit to authors).</p>
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<p>Comparison of production trials and results (credit to authors).</p>
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21 pages, 4718 KiB  
Article
Winter Wheat SPAD Prediction Based on Multiple Preprocessing, Sequential Module Fusion, and Feature Mining Methods
by Ying Nian, Xiangxiang Su, Hu Yue, Sumera Anwar, Jun Li, Weiqiang Wang, Yali Sheng, Qiang Ma, Jikai Liu and Xinwei Li
Agriculture 2024, 14(12), 2258; https://doi.org/10.3390/agriculture14122258 - 10 Dec 2024
Viewed by 584
Abstract
Chlorophyll is a crucial indicator for monitoring crop growth and assessing nutritional status. Hyperspectral remote sensing plays an important role in precision agriculture, offering a non-destructive approach to predicting leaf chlorophyll. However, crop canopy spectra often face background noise and data redundancy challenges. [...] Read more.
Chlorophyll is a crucial indicator for monitoring crop growth and assessing nutritional status. Hyperspectral remote sensing plays an important role in precision agriculture, offering a non-destructive approach to predicting leaf chlorophyll. However, crop canopy spectra often face background noise and data redundancy challenges. To tackle these issues, this study develops an integrated processing strategy incorporating multiple preprocessing techniques, sequential module fusion, and feature mining methods. Initially, the original spectrum (OS) from 2021, 2022, and the fusion year underwent preprocessing through Fast Fourier Transform (FFT) smoothing, multiple scattering correction (MSC), the first derivative (FD), and the second derivative (SD). Secondly, feature mining was conducted using Competitive Adaptive Reweighted Sampling (CARS), Iterative Retention of Information Variables (IRIV), and Principal Component Analysis (PCA) based on the optimal preprocessing order module fusion data. Finally, Partial Least Squares Regression (PLSR) was used to construct a prediction model for winter wheat SPAD to compare the prediction effects in different years and growth stages. The findings show that the preprocessing sequential module fusion of FFT-MSC (firstly pre-processing using FFT, and secondly secondary processing of FFT spectral data using MSC) effectively reduced issues such as noisy signals and baseline drift. The FFT-MSC-IRIV-PLSR model (based on the combined FFT-MSC preprocessed spectral data, feature screening using IRIV, and then combining with PLSR to construct a prediction model) predicts SPAD with the highest overall accuracy, with an R2 of 0.79–0.89, RMSE of 4.51–5.61, and MAE of 4.01–4.43. The model performed best in 2022, with an R2 of 0.84–0.89 and RMSE of 4.51–6.74. The best prediction during different growth stages occurred in the early filling stage, with an R2 of 0.75 and RMSE of 0.58. On the basis of this research, future work will focus on optimizing the data processing process and incorporating richer environmental data, so as to further enhance the predictive capability and applicability of the model. Full article
(This article belongs to the Section Digital Agriculture)
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<p>Study area. (<b>A</b>) The experiment field was in Chuzhou, Anhui province, China; (<b>B</b>) field experimental design.</p>
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<p>Technology roadmap for winter wheat SPAD prediction model development using canopy hyperspectral data.</p>
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<p>Comparison of spectral curves under different preprocessing methods: (<b>a</b>) original spectrum; (<b>b</b>) FFT-smoothed spectrum; (<b>c</b>) comparison of original and FFT-smoothed spectra; (<b>d</b>) MSC spectrum; (<b>e</b>) first-order derivative spectrum; (<b>f</b>) second-order derivative spectrum. The colored lines represent the spectral reflectance of all samples in the range of 400 nm to 900 nm.</p>
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<p>Comparison of modeling accuracy of different preprocessing methods under single and fused growth years: (<b>a</b>,<b>c</b>,<b>e</b>) predictive model validation set R<sup>2</sup>; (<b>b</b>,<b>d</b>,<b>f</b>) predictive model validation set RMSE; (<b>a</b>,<b>b</b>) 2021; (<b>c</b>,<b>d</b>) 2022; (<b>e</b>,<b>f</b>) fusion year.</p>
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<p>Comparison of modeling accuracy of different preprocessing methods under single and fused growth years: (<b>a</b>,<b>c</b>,<b>e</b>) predictive model validation set R<sup>2</sup>; (<b>b</b>,<b>d</b>,<b>f</b>) predictive model validation set RMSE; (<b>a</b>,<b>b</b>) 2021; (<b>c</b>,<b>d</b>) 2022; (<b>e</b>,<b>f</b>) fusion year.</p>
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<p>Wavelength selection for winter wheat SPAD prediction using CARS and IRIV methods across different growth years. The selected feature wavelengths in the blue (B), green (G), red-edge (RE), and near-infrared (NIR) regions are shown for 2021, 2022, and fusion years. The orange ellipses indicate the most relevant wavelength bands selected by the feature mining methods. The black line represents the average reflectance curve from 400 to 900 nm across the spectral range.</p>
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<p>Cumulative explanations of the variance of the first five principal components extracted by PCA: (<b>a</b>) 2021 and 2022; (<b>b</b>) year of fusion.</p>
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<p>Fitting scatter plots of SPAD prediction models based on different feature mining methods in single years and fused years: (<b>a</b>–<b>c</b>) CARS prediction model scatter plots; (<b>d</b>–<b>f</b>) IRIV prediction model scatter plots; (<b>g</b>–<b>i</b>) PCA prediction model scatter plots.</p>
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<p>Plots of statistical analysis of SPAD values for single and fused years: (<b>a</b>–<b>c</b>) histogram of SPAD frequencies; (<b>d</b>–<b>f</b>) spectral reflectance corresponding to different levels of SPAD.</p>
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29 pages, 2318 KiB  
Review
A Review of Smart Camera Sensor Placement in Construction
by Wei Tian, Hao Li, Hao Zhu, Yongwei Wang, Xianda Liu, Rongzheng Yang, Yujun Xie, Meng Zhang, Jun Zhu and Xiangyu Wang
Buildings 2024, 14(12), 3930; https://doi.org/10.3390/buildings14123930 - 9 Dec 2024
Viewed by 848
Abstract
Cameras, with their low cost and efficiency, are widely used in construction management and structural health monitoring. However, existing reviews on camera sensor placement (CSP) are outdated due to rapid technological advancements. Furthermore, the construction industry poses unique challenges for CSP implementation due [...] Read more.
Cameras, with their low cost and efficiency, are widely used in construction management and structural health monitoring. However, existing reviews on camera sensor placement (CSP) are outdated due to rapid technological advancements. Furthermore, the construction industry poses unique challenges for CSP implementation due to its scale, complexity, and dynamic nature. Previous reviews have not specifically addressed these industry-specific demands. This study aims to fill this gap by analyzing articles from the Web of Science and ASCE databases that focus exclusively on CSP in construction. A rigorous selection process ensures the relevance and quality of the included studies. This comprehensive review navigates through the complexities of camera and environment models, advocating for advanced optimization techniques like genetic algorithms, greedy algorithms, Swarm Intelligence, and Markov Chain Monte Carlo to refine CSP strategies. Simultaneously, Building Information Modeling is employed to consider the progress of construction and visualize optimized layouts, improving the effect of CSP. This paper delves into perspective distortion, the field of view considerations, and the occlusion impacts, proposing a unified framework that bridges practical execution with the theory of optimal CSP. Furthermore, the roadmap for future exploration in the CSP of construction is proposed. This work enriches the study of construction CSP, charting a course for future inquiry, and emphasizes the need for adaptable and technologically congruent CSP approaches amid evolving application landscapes. Full article
(This article belongs to the Special Issue Smart and Digital Construction in AEC Industry)
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<p>Research methodology.</p>
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<p>Methodological workflow.</p>
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<p>Camera mode: (<b>a</b>) bullet/dome camera, (<b>b</b>) omnidirectional cameras.</p>
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<p>The general framework of GAs.</p>
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<p>The iteration process of PSO.</p>
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<p>The camera placement optimization framework based on BIM.</p>
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18 pages, 5642 KiB  
Article
A New Slicer-Based Method to Generate Infill Inspired by Sandwich-Patterns for Reduced Material Consumption
by Patrick Steck, Dominik Schuler, Christian Witzgall and Sandro Wartzack
Materials 2024, 17(22), 5596; https://doi.org/10.3390/ma17225596 - 15 Nov 2024
Viewed by 758
Abstract
This work presents a novel infill method for additive manufacturing, specifically designed to optimize material use and enhance stiffness in fused filament fabrication (FFF) parts through a geometry-aware, corrugated design inspired by sandwich structures. Unlike standard infill patterns, which typically employ uniform, space-filling [...] Read more.
This work presents a novel infill method for additive manufacturing, specifically designed to optimize material use and enhance stiffness in fused filament fabrication (FFF) parts through a geometry-aware, corrugated design inspired by sandwich structures. Unlike standard infill patterns, which typically employ uniform, space-filling grids that often disregard load-specific requirements, this method generates a cavity inside the component to be printed and fill the space between inner and outer contours with continuous, adaptable extrusion paths. This design enables consistent support and improved load distribution, making it particularly effective for parts under bending stresses, as it enhances structural resilience without requiring additional material. Simulations performed on a 10 cm3 test part using this method showed potential reductions in material consumption by up to 77% and a decrease in print time by 78%, while maintaining stiffness comparable to parts using conventional 100% grid infill. Additionally, simulations demonstrated that the new corrugated infill pattern provides near-isotropic stiffness, addressing the anisotropic limitations often seen in traditional infill designs that are sensitive to load orientation. This geometry-aware infill strategy thus contributes to balanced stiffness across complex geometries, enhancing reliability under mechanical loads. By integrating directly with slicer software, this approach simplifies advanced stiffness optimization without the necessity of finite element analysis-based topology optimization. Full article
(This article belongs to the Special Issue Advanced Additive Manufacturing and Application)
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<p>Different adaptive infill patterns with build direction in z-axis: (<b>a</b>) Rhombic cell; (<b>b</b>) Gradual; (<b>c</b>) Cubic-subdivision.</p>
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<p>General process steps for generating G-codes. The input is an STL mesh. This mesh is then cut up. Paths are then planned from the individual slices by meshing again. The paths are then generated and finally output as G-code.</p>
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<p>Tool path generation process: This starts with the layer geometry. The wall paths are then defined. Next, an infill pattern is placed over the remaining inner geometry and, finally, the tool paths are generated.</p>
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<p>(<b>a</b>) Placement of hollowing-based infill in layers including a cavity. (<b>b</b>) Placement of corrugated infill pattern between inner and outer contours.</p>
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<p>Graphical explanation of the corrugated infill algorithm. Red dots mark the initial seed points. Blue dots mark the contact points with the outer and inner shell. Blue lines mark the contact regions (paths) with the outer and inner shell.</p>
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<p>Variation in the corrugated infill pattern by alternation of the seed path (red lines): (<b>a</b>) Unidirectional corrugated infill, in which the seeds are always placed collinear. (<b>b</b>) Bi-directional corrugated infill, in which the seeds are positioned alternately at a predefined distance. (<b>c</b>) Double-corrugated infill, in which the seeds are distributed at a constant distance from a starting point in both directions.</p>
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<p>Test part geometry: (<b>a</b>) Isometric view. (<b>b</b>) Outer dimensions of the test component for comparing the different infill types. (All units in the figure are in mm).</p>
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<p>The behavior of print time and material consumption with increasing geometry height for the different infill types using the sample geometry from <a href="#materials-17-05596-f007" class="html-fig">Figure 7</a>. The material volumes were generated simulatively using the software Klipper v0.11 (see <a href="#sec2dot2-materials-17-05596" class="html-sec">Section 2.2</a>).</p>
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<p>Geometry of the different three-point bending specimens. The geometries are simplified in the middle as symmetric.</p>
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<p>Qualitative deformation by three-point bending test using the corrugated infill as an example. The example is simplified in the middle as symmetric. The whole length of a specimen is 100 mm and the thickness is 5 mm. (Dimensions are in mm).</p>
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<p>Maximum deformation of simulative three-point bending test specimens. Gray are bending values for the infill patterns which are along the bending line, and blue are transverse to the bending line. The deformations were simulated using Ansys 2023 R2 software.</p>
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<p>Three-dimensional sketch of the test part for stiffness and stress comparison: force <math display="inline"><semantics> <msub> <mi>F</mi> <mi>z</mi> </msub> </semantics></math> and moment <math display="inline"><semantics> <msub> <mi>M</mi> <mi>y</mi> </msub> </semantics></math> are aligned in the middle of the structure, <span class="html-italic">p</span> is a pressure that occurs in the inside of the pipe. The pipe is fixed through both end surfaces in the <span class="html-italic">y</span>-direction. (All units in the figure are in mm).</p>
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<p>Analysis results (view in to x–z plane, see <a href="#materials-17-05596-f012" class="html-fig">Figure 12</a>): (<b>a</b>–<b>f</b>) Grid, (<b>g</b>–<b>l</b>) corrugated, (<b>m</b>–<b>r</b>) bi-corrugated, (<b>a</b>,<b>g</b>,<b>m</b>) bending deformation, (<b>b</b>,<b>h</b>,<b>n</b>) bending stress, (<b>c</b>,<b>i</b>,<b>o</b>) torsion deformation, (<b>d</b>,<b>j</b>,<b>p</b>) torsion stress, (<b>e</b>,<b>k</b>,<b>q</b>) pressure deformation, (<b>f</b>,<b>l</b>,<b>r</b>) pressure stress.</p>
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<p>Print time example of two different infill types. Extrusion path (black lines); travel path (red lines); start and finish point (green mark). The underlying geometry is the test geometry from <a href="#materials-17-05596-f007" class="html-fig">Figure 7</a>, scaled with a scaling factor of 10: (<b>a</b>) Conventional grid infill; (<b>b</b>) Corrugated infill.</p>
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13 pages, 4675 KiB  
Article
Hierarchical Optimal Dispatching of Electric Vehicles Based on Photovoltaic-Storage Charging Stations
by Ziyuan Liu, Junjing Tan, Wei Guo, Chong Fan, Wenhe Peng, Zhijian Fang and Jingke Gao
Mathematics 2024, 12(21), 3410; https://doi.org/10.3390/math12213410 - 31 Oct 2024
Viewed by 957
Abstract
Electric vehicles, known for their eco-friendliness and rechargeable–dischargeable capabilities, can serve as energy storage batteries to support the operation of the microgrid in certain scenarios. Therefore, photovoltaic-storage electric vehicle charging stations have emerged as an important solution to address the challenges posed by [...] Read more.
Electric vehicles, known for their eco-friendliness and rechargeable–dischargeable capabilities, can serve as energy storage batteries to support the operation of the microgrid in certain scenarios. Therefore, photovoltaic-storage electric vehicle charging stations have emerged as an important solution to address the challenges posed by energy interconnection networks. However, electric vehicle charging loads exhibit notable randomness, potentially altering load characteristics during certain periods and posing challenges to the stable operation of microgrids. To address this challenge, this paper proposes a hierarchical optimal dispatching strategy based on photovoltaic-storage charging stations. The strategy utilizes a dynamic electricity pricing model and the adaptive particle swarm optimization algorithm to effectively manage electric vehicle charging loads. By decomposing the dispatching task into multiple layers, the strategy effectively solves the problems of the “curse of dimensionality” and slow convergence associated with large numbers of electric vehicles. Simulation results demonstrate that the strategy can effectively achieve peak shaving and valley filling, reducing the load variance of the microgrid by 24.93%, and significantly reduce electric vehicle charging costs and distribution network losses, with a reduction of 92.29% in electric vehicle charging costs and 32.28% in microgrid losses compared to unorganized charging. Additionally, this strategy can meet the travel demands of electric vehicle owners while providing convenient charging services. Full article
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<p>Charging and discharging model of EV unit.</p>
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<p>Dispatching framework of PV-storage charging station.</p>
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<p>IEEE33-node system.</p>
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<p>Conventional load, PV output, and TOU electricity price of microgrid.</p>
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<p>Charging load of EV before and after scheduling.</p>
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<p>Charging and discharging power of energy storage.</p>
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<p>Load of microgrid before and after scheduling.</p>
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<p>Real-time electricity price.</p>
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<p>Voltage of distribution network nodes.</p>
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<p>Current of distribution network nodes.</p>
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<p>Network loss of distribution network.</p>
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<p>SOC of EV after scheduling.</p>
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33 pages, 8912 KiB  
Article
Real-Time Control of Thermal Synchronous Generators for Cyber-Physical Security: Addressing Oscillations with ANFIS
by Ahmed Khamees and Hüseyin Altınkaya
Processes 2024, 12(11), 2345; https://doi.org/10.3390/pr12112345 - 25 Oct 2024
Cited by 1 | Viewed by 949
Abstract
This paper introduces a novel real-time ANFIS controller, specifically designed for thermal synchronous generators, to mitigate the risks associated with cyber-physical attacks on power systems. The controller integrates the dynamic model of the turbine’s thermomechanical components, such as the boiler and heat transfer [...] Read more.
This paper introduces a novel real-time ANFIS controller, specifically designed for thermal synchronous generators, to mitigate the risks associated with cyber-physical attacks on power systems. The controller integrates the dynamic model of the turbine’s thermomechanical components, such as the boiler and heat transfer processes, within the synchronous generator. In contrast to previous studies, this model is designed for practical implementation and addresses often-overlooked areas, including the interaction between electrical and thermomechanical components, real-time control responses to cyber-physical attacks, and the incorporation of economic considerations alongside technical performance. This study takes a comprehensive approach to filling these gaps. Under normal conditions, the proposed controller significantly improves the management of industrial turbines and governors, optimizing existing control systems with a particular focus on minimizing generation costs. However, its primary innovation is its ability to respond dynamically to local and inter-area power oscillations triggered by cyber-physical attacks. In such events, the controller efficiently manages the turbines and governors of synchronous generators, ensuring the stability and reliability of power systems. This approach introduces a cutting-edge thermo-electrical control strategy that integrates both electrical and thermomechanical dynamics of thermal synchronous generators. The novelty lies in its real-time control capability to counteract the effects of cyber-physical attacks, as well as its simultaneous consideration of economic optimization and technical performance for power system stability. Unlike traditional methods, this work offers an adaptive control system using ANFIS (Adaptive NeuroFuzzy Inference System), ensuring robust performance under dynamic conditions, including interarea oscillations and voltage deviations. To validate its effectiveness, the controller undergoes extensive simulation testing in MATLAB/Simulink, with performance comparisons against previous state-of-the-art methods. Benchmarking is also conducted using IEEE standard test systems, including the IEEE 9-bus and IEEE 39-bus networks, to highlight its superiority in protecting power systems. Full article
(This article belongs to the Special Issue AI-Based Modelling and Control of Power Systems)
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<p>Conceptual model of the proposed scheme for real-time control of the generators.</p>
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<p>Proposed real-time ANFIS control flowchart for safeguarding thermal turbines from physical cyber-attacks: illustrating process stages.</p>
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<p>Schematic of gas turbine and proposed optimal ANFIS controller.</p>
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<p>Structure of neural network for proposed ANFIS controller.</p>
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<p>Input and output membership functions of the proposed ANFIS controller.</p>
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<p>Input and output membership functions of the proposed ANFIS controller.</p>
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<p>Process of choosing the best solution, feasible region, and path within the Pareto front.</p>
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<p>IEEE 9-bus case study schematic.</p>
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<p>An exploded Pareto graphic showing the best objective functions in the IEEE 9-bus network.</p>
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<p>Aggregate cost and overall speed variation of IEEE 9-bus during the event of line disconnection between nodes 5 and 7.</p>
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<p>Voltage deviation in IEEE 9-bus following line disruption between buses 5 and 7.</p>
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<p>Generators’ rotor angle and power output in IEEE 9-bus network (under permanent magnet operating condition) and during line disruption between bus 5 and bus 7.</p>
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<p>Turbine temperature of generators in IEEE 9-bus network (under permanent magnet operating condition) during line disruption between bus 5 and bus 7.</p>
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<p>Schematic of IEEE 39-bus case study.</p>
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<p>Aggregate cost and overall speed variation of IEEE 39-bus during the event of line disconnection between nodes 4 and 14. (<b>a</b>) shows the total speed deviation (in per unit) over time for different control methods: PID Control of Turbine and Governor (black), Classical Control of Turbine and Governor (red), and Optimal ANFIS Controller (blue). The optimal ANFIS controller exhibits significantly lower oscillations and faster stabilization compared to the other methods; (<b>b</b>) displays the total cost (<span>$</span>) over time for the same control methods. The Optimal ANFIS Controller consistently results in the lowest operational cost, followed by the Classical Control and PID Control methods.</p>
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<p>Voltage deviation in IEEE 39-bus following line disruption between buses 4 and 14.</p>
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<p>Mechanical output power in IEEE 39-bus network (under permanent magnet operating condition) and during line disruption between bus 4 and bus 14.</p>
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<p>Turbine temperature of generators in IEEE 39-bus network (under permanent magnet operating condition) and during line disruption between bus 4 and bus 14.</p>
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13 pages, 3302 KiB  
Article
ADPA Optimization for Real-Time Energy Management Using Deep Learning
by Zhengdong Wan, Yan Huang, Liangzheng Wu and Chengwei Liu
Energies 2024, 17(19), 4821; https://doi.org/10.3390/en17194821 - 26 Sep 2024
Cited by 1 | Viewed by 761
Abstract
The current generation of renewable energy remains insufficient to meet the demands of users within the network, leading to the necessity of curtailing flexible loads and underscoring the urgent need for optimized microgrid energy management. In this study, the deep learning-based Adaptive Dynamic [...] Read more.
The current generation of renewable energy remains insufficient to meet the demands of users within the network, leading to the necessity of curtailing flexible loads and underscoring the urgent need for optimized microgrid energy management. In this study, the deep learning-based Adaptive Dynamic Programming Algorithm (ADPA) was introduced to integrate real-time pricing into the optimization of demand-side energy management for microgrids. This approach not only achieved a dynamic balance between supply and demand, along with peak shaving and valley filling, but it also enhanced the rationality of energy management strategies, thereby ensuring stable microgrid operation. Simulations of the Real-Time Electricity Price (REP) management model under demand-side response conditions validated the effectiveness and feasibility of this approach in microgrid energy management. Based on the deep neural network model, optimization of the objective function was achieved with merely 54 epochs, suggesting a highly efficient computational process. Furthermore, the integration of microgrid energy management with the REP conformed to the distributed multi-source power supply microgrid energy management and scheduling and improved the efficiency of clean energy utilization significantly, supporting the implementation of national policies aimed at the development of a sustainable power grid. Full article
(This article belongs to the Section F5: Artificial Intelligence and Smart Energy)
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<p>Deep learning ADPA: (<b>a</b>) fundamental framework; (<b>b</b>) multilayer neural network topology.</p>
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<p>Power generation: (<b>a</b>) hydroelectric power generation; (<b>b</b>) gas power generation; (<b>c</b>) distributed power storage device.</p>
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<p>Objective function setting and output training process: (<b>a</b>) error optimization process; (<b>b</b>) iterative regression process; and (<b>c</b>) the number of iterations of the best-fit parameter under the minimum error.</p>
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<p>REP of microgrid and corresponding purchased electricity: (<b>a</b>) REP corresponding to the purchase of electricity; (<b>b</b>) REP corresponding to supply–demand balance.</p>
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<p>Relationships between REP and microgrid power supply and demand: (<b>a</b>) the relationship between the total supply and total demand; (<b>b</b>) the relationship between the power and rigid-load and maximum power demands.</p>
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25 pages, 12356 KiB  
Article
Efficient On-Board Compression for Arbitrary-Shaped Cloud-Covered Remote Sensing Images via Adaptive Filling and Controllable Quantization
by Keyan Wang, Jia Jia, Peicheng Zhou, Haoyi Ma, Liyun Yang, Kai Liu and Yunsong Li
Remote Sens. 2024, 16(18), 3431; https://doi.org/10.3390/rs16183431 - 15 Sep 2024
Cited by 1 | Viewed by 970
Abstract
Due to the fact that invalid cloud-covered regions in remote sensing images consume a considerable quantity of coding bit rates under the limited satellite-to-ground transmission rate, existing image compression methods suffer from low compression efficiency and poor reconstruction quality, especially in cloud-free regions [...] Read more.
Due to the fact that invalid cloud-covered regions in remote sensing images consume a considerable quantity of coding bit rates under the limited satellite-to-ground transmission rate, existing image compression methods suffer from low compression efficiency and poor reconstruction quality, especially in cloud-free regions which are generally regarded as regions of interest (ROIs). Therefore, we propose an efficient on-board compression method for remote sensing images with arbitrary-shaped clouds by leveraging the characteristics of cloudy images. Firstly, we introduce two novel spatial preprocessing strategies, namely, the optimized adaptive filling (OAF) strategy and the controllable quantization (CQ) strategy. Specifically, the OAF strategy fills each cloudy region using the contextual information at its inner and outer edge to completely remove the information of cloudy regions and minimize their coding consumption, which is suitable for images with only thick clouds. The CQ strategy implicitly identifies thin and thick clouds and rationally quantifies the data in cloudy regions to alleviate information loss in thin cloud-covered regions, which can achieve the balance between coding efficiency and reconstructed image quality and is more suitable for images containing thin clouds. Secondly, we develop an efficient coding method for a binary cloud mask to effectively save the bit rate of the side information. Our method provides the flexibility for users to choose the desired preprocessing strategy as needed and can be embedded into existing compression framework such as JPEG2000. Experimental results on the GF-1 dataset show that our method effectively reduces the coding consumption of invalid cloud-covered regions and significantly improve the compression efficiency as well as the quality of decoded images. Full article
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<p>The categories of clouds in the remote sensing image. (<b>a</b>,<b>b</b>) are thick clouds, (<b>c</b>) is thin cloud. The close-up views of the regions marked by red boxes are shown at the bottom right corner.</p>
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<p>Intensity histograms of cloud-free remote sensing images. (<b>a</b>–<b>c</b>) are the original images. (<b>d</b>–<b>f</b>) are the corresponding gray value histograms of (<b>a</b>–<b>c</b>), respectively.</p>
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<p>Intensity histograms of cloud-covered remote sensing images. (<b>a</b>,<b>f</b>,<b>k</b>) are the original images. (<b>b</b>,<b>g</b>,<b>l</b>) are cloud masks of (<b>a</b>), (<b>f</b>), (<b>k</b>), respectively. (<b>c</b>,<b>h</b>,<b>m</b>) are histograms of (<b>a</b>), (<b>f</b>), (<b>k</b>), respectively. (<b>d</b>,<b>i</b>,<b>n</b>) are histograms of ground object of (<b>a</b>), (<b>f</b>), (<b>k</b>), respectively. (<b>e</b>,<b>j</b>,<b>o</b>) are histograms of cloudy regions of (<b>a</b>), (<b>f</b>), (<b>k</b>), respectively.</p>
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<p>The overall codec framework.</p>
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<p>The processing flow of the optimized adaptive filling strategy.</p>
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<p>Schematic diagram of boundary filtering on the filled cloudy region.</p>
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<p>Comparison of cloudy region filling by using the preprocessing modules of different image compression methods. (<b>a</b>) is original image. (<b>b</b>) is cloud mask of (<b>a</b>), where white regions (gray value of 255) denote clouds and black regions (gray value of 0) denote ground objects. (<b>c</b>–<b>e</b>) are results of filling the cloudy region using ADR, LEC, and OAF (our method), respectively. The close-up views of the regions marked by red boxes are shown at the bottom right corner, which clearly shows the smoothness of the boundary after filling cloudy regions with different strategies.</p>
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<p>Results of different quantization methods. (<b>a</b>) is original image. (<b>b</b>) is cloud mask of (<b>a</b>). (<b>c</b>) is the result of quantization. (<b>d</b>) is the result of CQ. The close-up views of the regions marked by red boxes are shown at the bottom right corner.</p>
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<p>The processing flow of the controllable quantization strategy. The close-up views of the regions marked by red boxes are shown at the bottom right corner.</p>
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<p>The quantization of the data in cloudy regions in the spatial domain. The close-up views of the regions marked by red boxes in the original image are shown at the bottom left corner.</p>
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<p>The processing flow of binary cloud mask encoding.</p>
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<p>The processing flow of symbol packaging.</p>
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<p>The contrast of the decoded images before and after image post-processing. (<b>a</b>) is original image, (<b>b</b>) is cloud mask of (<b>a</b>). (<b>c</b>) OAF without post-processing, (<b>d</b>) OAF with post-processing, (<b>e</b>) CQ without post-processing, (<b>f</b>) CQ with post-processing.</p>
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<p>Examples of evaluation dataset. (<b>a</b>–<b>e</b>) are GF-1 remote sensing images including ice and snow, water, urban area, farmland, and forest, respectively, (<b>f</b>), (<b>g</b>), (<b>h</b>), (<b>i</b>), (<b>j</b>) are the corresponding cloud masks of (<b>a</b>), (<b>b</b>), (<b>c</b>), (<b>d</b>), (<b>e</b>) respectively.</p>
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<p>The decoded images by using CQ with different S and D values. The close-up views of the regions marked by red boxes are shown at the top right corner and the top left corner. (<b>a</b>) is original image, (<b>b</b>) is cloud mask of (<b>a</b>). (<b>c</b>) D = 0, S = 0, <math display="inline"><semantics> <mrow> <mi>P</mi> <mi>S</mi> <mi>N</mi> <msub> <mi>R</mi> <mrow> <mi>R</mi> <mi>O</mi> <mi>I</mi> </mrow> </msub> </mrow> </semantics></math> = 60.14 dB, (<b>d</b>) D = 0, S = 2, <math display="inline"><semantics> <mrow> <mi>P</mi> <mi>S</mi> <mi>N</mi> <msub> <mi>R</mi> <mrow> <mi>R</mi> <mi>O</mi> <mi>I</mi> </mrow> </msub> </mrow> </semantics></math> = 62.83 dB, (<b>e</b>) D = 0, S = 4, <math display="inline"><semantics> <mrow> <mi>P</mi> <mi>S</mi> <mi>N</mi> <msub> <mi>R</mi> <mrow> <mi>R</mi> <mi>O</mi> <mi>I</mi> </mrow> </msub> </mrow> </semantics></math> = 63.54 dB, (<b>f</b>) D = 0, S = 6, <math display="inline"><semantics> <mrow> <mi>P</mi> <mi>S</mi> <mi>N</mi> <msub> <mi>R</mi> <mrow> <mi>R</mi> <mi>O</mi> <mi>I</mi> </mrow> </msub> </mrow> </semantics></math> = 65.21 dB, (<b>g</b>) D = 4, S = 2, <math display="inline"><semantics> <mrow> <mi>P</mi> <mi>S</mi> <mi>N</mi> <msub> <mi>R</mi> <mrow> <mi>R</mi> <mi>O</mi> <mi>I</mi> </mrow> </msub> </mrow> </semantics></math> = 63.01 dB, (<b>h</b>) D = 4, S = 4, <math display="inline"><semantics> <mrow> <mi>P</mi> <mi>S</mi> <mi>N</mi> <msub> <mi>R</mi> <mrow> <mi>R</mi> <mi>O</mi> <mi>I</mi> </mrow> </msub> </mrow> </semantics></math> = 63.87 dB, (<b>i</b>) D = 16, S = 2, <math display="inline"><semantics> <mrow> <mi>P</mi> <mi>S</mi> <mi>N</mi> <msub> <mi>R</mi> <mrow> <mi>R</mi> <mi>O</mi> <mi>I</mi> </mrow> </msub> </mrow> </semantics></math> = 63.95 dB.</p>
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<p>Image 1.The percentage of clouds was 50%. (<b>a</b>) is original image, (<b>b</b>) is cloud mask of (<b>a</b>). The close-up views of the regions marked by red boxes are shown at the top left corner and the bottom left corner.</p>
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<p>Image 2. The percentage of could was 50%. (<b>a</b>) is original image, (<b>b</b>) is cloud mask of (<b>a</b>). The close-up views of the regions marked by red boxes are shown at the bottom left corner.</p>
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<p>Comparison of subjective quality of decoded image 1. The close-up views of the regions marked by red boxes are shown at the bottom left corner and the top left corner. The compression ratio was 4. (<b>a</b>) JPEG2000 <math display="inline"><semantics> <mrow> <mi>P</mi> <mi>S</mi> <mi>N</mi> <msub> <mi>R</mi> <mrow> <mi>R</mi> <mi>O</mi> <mi>I</mi> </mrow> </msub> </mrow> </semantics></math> = 61.98 dB, (<b>b</b>) ADR + JPEG2000 <math display="inline"><semantics> <mrow> <mi>P</mi> <mi>S</mi> <mi>N</mi> <msub> <mi>R</mi> <mrow> <mi>R</mi> <mi>O</mi> <mi>I</mi> </mrow> </msub> </mrow> </semantics></math> = 65.61 dB, (<b>c</b>) LEC + JPEG2000 <math display="inline"><semantics> <mrow> <mi>P</mi> <mi>S</mi> <mi>N</mi> <msub> <mi>R</mi> <mrow> <mi>R</mi> <mi>O</mi> <mi>I</mi> </mrow> </msub> </mrow> </semantics></math> = 66.48 dB, (<b>d</b>) OAF + JPEG2000(<math display="inline"><semantics> <mrow> <mi>D</mi> <msub> <mi>C</mi> <mrow> <mi>o</mi> <mi>p</mi> <mi>t</mi> </mrow> </msub> </mrow> </semantics></math>) <math display="inline"><semantics> <mrow> <mi>P</mi> <mi>S</mi> <mi>N</mi> <msub> <mi>R</mi> <mrow> <mi>R</mi> <mi>O</mi> <mi>I</mi> </mrow> </msub> </mrow> </semantics></math> = 67.75 dB, (<b>e</b>) CQ (D = 4, S = 2) + JPEG2000(<math display="inline"><semantics> <mrow> <mi>D</mi> <msub> <mi>C</mi> <mrow> <mi>o</mi> <mi>p</mi> <mi>t</mi> </mrow> </msub> </mrow> </semantics></math>) <math display="inline"><semantics> <mrow> <mi>P</mi> <mi>S</mi> <mi>N</mi> <msub> <mi>R</mi> <mrow> <mi>R</mi> <mi>O</mi> <mi>I</mi> </mrow> </msub> </mrow> </semantics></math> = 64.70 dB, (<b>f</b>) CQ (D = 1024, S = 10) + JPEG2000(<math display="inline"><semantics> <mrow> <mi>D</mi> <msub> <mi>C</mi> <mrow> <mi>o</mi> <mi>p</mi> <mi>t</mi> </mrow> </msub> </mrow> </semantics></math>) <math display="inline"><semantics> <mrow> <mi>P</mi> <mi>S</mi> <mi>N</mi> <msub> <mi>R</mi> <mrow> <mi>R</mi> <mi>O</mi> <mi>I</mi> </mrow> </msub> </mrow> </semantics></math> = 67.18 dB.</p>
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<p>Comparison of subjective quality of the decoded image of image 1. The close-up views of the regions marked by red boxes are shown at the bottom left corner and the top left corner. The compression ratio was 64. (<b>a</b>) JPEG2000. <math display="inline"><semantics> <mrow> <mi>P</mi> <mi>S</mi> <mi>N</mi> <msub> <mi>R</mi> <mrow> <mi>R</mi> <mi>O</mi> <mi>I</mi> </mrow> </msub> </mrow> </semantics></math> = 32.76 dB, (<b>b</b>) ADR + JPEG2000 <math display="inline"><semantics> <mrow> <mi>P</mi> <mi>S</mi> <mi>N</mi> <msub> <mi>R</mi> <mrow> <mi>R</mi> <mi>O</mi> <mi>I</mi> </mrow> </msub> </mrow> </semantics></math> = 32.98 dB, (<b>c</b>) LEC + JPEG2000 <math display="inline"><semantics> <mrow> <mi>P</mi> <mi>S</mi> <mi>N</mi> <msub> <mi>R</mi> <mrow> <mi>R</mi> <mi>O</mi> <mi>I</mi> </mrow> </msub> </mrow> </semantics></math> = 33.50 dB, (<b>d</b>) OAF + JPEG2000(<math display="inline"><semantics> <mrow> <mi>D</mi> <msub> <mi>C</mi> <mrow> <mi>o</mi> <mi>p</mi> <mi>t</mi> </mrow> </msub> </mrow> </semantics></math><math display="inline"><semantics> <mrow> <mi>P</mi> <mi>S</mi> <mi>N</mi> <msub> <mi>R</mi> <mrow> <mi>R</mi> <mi>O</mi> <mi>I</mi> </mrow> </msub> </mrow> </semantics></math> = 34.97 dB, (<b>e</b>) CQ (D = 4, S = 2) + JPEG2000(<math display="inline"><semantics> <mrow> <mi>D</mi> <msub> <mi>C</mi> <mrow> <mi>o</mi> <mi>p</mi> <mi>t</mi> </mrow> </msub> </mrow> </semantics></math>) <math display="inline"><semantics> <mrow> <mi>P</mi> <mi>S</mi> <mi>N</mi> <msub> <mi>R</mi> <mrow> <mi>R</mi> <mi>O</mi> <mi>I</mi> </mrow> </msub> </mrow> </semantics></math> = 33.45 dB, (<b>f</b>) CQ (D = 1024, S = 10) + JPEG2000(<math display="inline"><semantics> <mrow> <mi>D</mi> <msub> <mi>C</mi> <mrow> <mi>o</mi> <mi>p</mi> <mi>t</mi> </mrow> </msub> </mrow> </semantics></math>) <math display="inline"><semantics> <mrow> <mi>P</mi> <mi>S</mi> <mi>N</mi> <msub> <mi>R</mi> <mrow> <mi>R</mi> <mi>O</mi> <mi>I</mi> </mrow> </msub> </mrow> </semantics></math> = 34.04 dB.</p>
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<p>Comparison of subjective quality of the decoded image of image 2. The close-up views of the regions marked by red boxes are shown at the bottom left corner and the top left corner. The compression ratio was 4. (<b>a</b>) JPEG2000. <math display="inline"><semantics> <mrow> <mi>P</mi> <mi>S</mi> <mi>N</mi> <msub> <mi>R</mi> <mrow> <mi>R</mi> <mi>O</mi> <mi>I</mi> </mrow> </msub> </mrow> </semantics></math> = 61.84 dB, (<b>b</b>) ADR + JPEG2000 <math display="inline"><semantics> <mrow> <mi>P</mi> <mi>S</mi> <mi>N</mi> <msub> <mi>R</mi> <mrow> <mi>R</mi> <mi>O</mi> <mi>I</mi> </mrow> </msub> </mrow> </semantics></math> = 64.55 dB, (<b>c</b>) LEC + JPEG2000 <math display="inline"><semantics> <mrow> <mi>P</mi> <mi>S</mi> <mi>N</mi> <msub> <mi>R</mi> <mrow> <mi>R</mi> <mi>O</mi> <mi>I</mi> </mrow> </msub> </mrow> </semantics></math> = 66.71 dB, (<b>d</b>) OAF + JPEG2000(<math display="inline"><semantics> <mrow> <mi>D</mi> <msub> <mi>C</mi> <mrow> <mi>o</mi> <mi>p</mi> <mi>t</mi> </mrow> </msub> </mrow> </semantics></math>) <math display="inline"><semantics> <mrow> <mi>P</mi> <mi>S</mi> <mi>N</mi> <msub> <mi>R</mi> <mrow> <mi>R</mi> <mi>O</mi> <mi>I</mi> </mrow> </msub> </mrow> </semantics></math> = 69.69 dB, (<b>e</b>) CQ (D = 4, S = 2) + JPEG2000(<math display="inline"><semantics> <mrow> <mi>D</mi> <msub> <mi>C</mi> <mrow> <mi>o</mi> <mi>p</mi> <mi>t</mi> </mrow> </msub> </mrow> </semantics></math>) <math display="inline"><semantics> <mrow> <mi>P</mi> <mi>S</mi> <mi>N</mi> <msub> <mi>R</mi> <mrow> <mi>R</mi> <mi>O</mi> <mi>I</mi> </mrow> </msub> </mrow> </semantics></math> = 65.22 dB, (<b>f</b>) CQ (D = 1024, S = 10) + JPEG2000(<math display="inline"><semantics> <mrow> <mi>D</mi> <msub> <mi>C</mi> <mrow> <mi>o</mi> <mi>p</mi> <mi>t</mi> </mrow> </msub> </mrow> </semantics></math>) <math display="inline"><semantics> <mrow> <mi>P</mi> <mi>S</mi> <mi>N</mi> <msub> <mi>R</mi> <mrow> <mi>R</mi> <mi>O</mi> <mi>I</mi> </mrow> </msub> </mrow> </semantics></math> = 69.01 dB.</p>
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<p>Comparison of subjective quality of the decoded image of image 2. The close-up views of the regions marked by red boxes are shown at the bottom left corner. The compression ratio was 64. (<b>a</b>) JPEG2000. <math display="inline"><semantics> <mrow> <mi>P</mi> <mi>S</mi> <mi>N</mi> <msub> <mi>R</mi> <mrow> <mi>R</mi> <mi>O</mi> <mi>I</mi> </mrow> </msub> </mrow> </semantics></math> = 28.45dB, (<b>b</b>) ADR + JPEG2000 <math display="inline"><semantics> <mrow> <mi>P</mi> <mi>S</mi> <mi>N</mi> <msub> <mi>R</mi> <mrow> <mi>R</mi> <mi>O</mi> <mi>I</mi> </mrow> </msub> </mrow> </semantics></math> = 32.38 dB, (<b>c</b>) LEC + JPEG2000 <math display="inline"><semantics> <mrow> <mi>P</mi> <mi>S</mi> <mi>N</mi> <msub> <mi>R</mi> <mrow> <mi>R</mi> <mi>O</mi> <mi>I</mi> </mrow> </msub> </mrow> </semantics></math> = 33.73 dB, (<b>d</b>) OAF + JPEG2000(<math display="inline"><semantics> <mrow> <mi>D</mi> <msub> <mi>C</mi> <mrow> <mi>o</mi> <mi>p</mi> <mi>t</mi> </mrow> </msub> </mrow> </semantics></math>) <math display="inline"><semantics> <mrow> <mi>P</mi> <mi>S</mi> <mi>N</mi> <msub> <mi>R</mi> <mrow> <mi>R</mi> <mi>O</mi> <mi>I</mi> </mrow> </msub> </mrow> </semantics></math> = 36.53 dB, (<b>e</b>) CQ (D = 4, S = 2) + JPEG2000(<math display="inline"><semantics> <mrow> <mi>D</mi> <msub> <mi>C</mi> <mrow> <mi>o</mi> <mi>p</mi> <mi>t</mi> </mrow> </msub> </mrow> </semantics></math>) <math display="inline"><semantics> <mrow> <mi>P</mi> <mi>S</mi> <mi>N</mi> <msub> <mi>R</mi> <mrow> <mi>R</mi> <mi>O</mi> <mi>I</mi> </mrow> </msub> </mrow> </semantics></math> = 33.82 dB, (<b>f</b>) CQ (D = 1024, S = 10) + JPEG2000(<math display="inline"><semantics> <mrow> <mi>D</mi> <msub> <mi>C</mi> <mrow> <mi>o</mi> <mi>p</mi> <mi>t</mi> </mrow> </msub> </mrow> </semantics></math>) <math display="inline"><semantics> <mrow> <mi>P</mi> <mi>S</mi> <mi>N</mi> <msub> <mi>R</mi> <mrow> <mi>R</mi> <mi>O</mi> <mi>I</mi> </mrow> </msub> </mrow> </semantics></math> = 36.13 dB.</p>
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26 pages, 10477 KiB  
Article
Interval Constrained Multi-Objective Optimization Scheduling Method for Island-Integrated Energy Systems Based on Meta-Learning and Enhanced Proximal Policy Optimization
by Dongbao Jia, Ming Cao, Jing Sun, Feimeng Wang, Wei Xu and Yichen Wang
Electronics 2024, 13(17), 3579; https://doi.org/10.3390/electronics13173579 - 9 Sep 2024
Cited by 1 | Viewed by 1030
Abstract
Multiple uncertainties from source–load and energy conversion significantly impact the real-time dispatch of an island integrated energy system (IIES). This paper addresses the day-ahead scheduling problems of IIES under these conditions, aiming to minimize daily economic costs and maximize the output of renewable [...] Read more.
Multiple uncertainties from source–load and energy conversion significantly impact the real-time dispatch of an island integrated energy system (IIES). This paper addresses the day-ahead scheduling problems of IIES under these conditions, aiming to minimize daily economic costs and maximize the output of renewable energies. We introduce an innovative algorithm for Interval Constrained Multi-objective Optimization Problems (ICMOPs), which incorporates meta-learning and an improved Proximal Policy Optimization with Clipped Objective (PPO-CLIP) approach. This algorithm fills a notable gap in the application of DRL to complex ICMOPs within the field. Initially, the multi-objective problem is decomposed into several single-objective problems using a uniform weight decomposition method. A meta-model trained via meta-learning enables fine-tuning to adapt solutions for subsidiary problems once the initial training is complete. Additionally, we enhance the PPO-CLIP framework with a novel strategy that integrates probability shifts and Generalized Advantage Estimation (GAE). In the final stage of scheduling plan selection, a technique for identifying interval turning points is employed to choose the optimal plan from the Pareto solution set. The results demonstrate that the method not only secures excellent scheduling solutions in complex environments through its robust generalization capabilities but also shows significant improvements over interval-constrained multi-objective evolutionary algorithms, such as IP-MOEA, ICMOABC, and IMOMA-II, across multiple multi-objective evaluation metrics including hypervolume (HV), runtime, and uncertainty. Full article
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<p>IIES architecture.</p>
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<p>MOMAML-PPO solution process.</p>
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<p>Solution selection at interval knee points.</p>
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<p>Meta-learning training.</p>
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<p>Schematic of the enhanced PPO-CLIP method.</p>
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<p>Forecasting renewable energy output and multiple load demands.</p>
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<p>Comparison of wind power output intervals under different confidence levels.</p>
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<p>The 95% confidence interval forecasting for renewable energy output and load demands.</p>
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<p>Pareto frontier of the ICMOP solution. (<b>a</b>) Pareto front boundary point plot; (<b>b</b>) Pareto front matrix plot.</p>
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<p>Scheduling results.</p>
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<p>Sensitivity analysis of the learning rate parameter in actor–critic networks.</p>
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<p>Sensitivity analysis of the reward discount factor in coefficient parameters.</p>
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<p>Average reward change curve.</p>
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<p>Dispatch strategy under emergency conditions: (<b>a</b>) scheduling results for Emergent Scenario 1; (<b>b</b>) scheduling results for Emergent Scenario 2.</p>
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21 pages, 9112 KiB  
Article
Stepwise Construction and Integration of Ecological Network in Resource-Based Regions: A Case Study on Liaoning Province, China
by Shaoqing Wang, Yanling Zhao, He Ren and Shichao Zhu
Remote Sens. 2024, 16(17), 3228; https://doi.org/10.3390/rs16173228 - 31 Aug 2024
Viewed by 933
Abstract
Ecological networks are an effective strategy to maintain regional ecological security. However, current research on ecological network construction in areas with large-scale resource extraction is limited. Moreover, classic ecological network construction methods do not perform satisfactorily when implemented in heavily damaged mining landscapes. [...] Read more.
Ecological networks are an effective strategy to maintain regional ecological security. However, current research on ecological network construction in areas with large-scale resource extraction is limited. Moreover, classic ecological network construction methods do not perform satisfactorily when implemented in heavily damaged mining landscapes. Taking the example of Liaoning Province, China, a framework for stepwise renewal of ecological networks was proposed, which integrates basic ecological sources and other sources that include mining areas. The framework was based on multi-source ecological environment monitoring data, and all potential ecological sources were extracted and screened using an MSPA model and the area threshold method. Further, ecological sources were classified into two types and three levels based on the influence of abandoned mines and the characteristics of ecosystem services in the ecological sources. Ecological corridors were extracted using the MCR model. An ecological corridor optimization process based on combining the gravity model with addition and removal rules of corridors was proposed. The results indicated that the basic ecological network in Liaoning Province included 101 ecological sources and 162 ecological corridors, and the supplementary ecological network included 28 ecological sources and 67 ecological corridors. The ecological sources were divided into two types, and corridors were divided into three types. The basic ecological network exhibited a spatial distribution of discrete connections in the west and close connections in the east. Changes in ecological network topological indicators indicated that a supplementary ecological network strengthened the structural performance of the regional ecological network, expanding spatial coverage, filling hollow areas, and enriching local details of the regional ecological network. Regulation strategies were proposed for ecological sources with different connection modes. The number of ecological sources implementing restrictive development, pattern optimization, and protective development were 101, 12, and 16, respectively. This paper provides a constructing framework of ecological networks adapted for resource-based regions. This method can support decisions for the environmental governance of mines, thus contributing to a balance between resource exploitation and ecological protection in regions. Full article
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<p>Geographical location and land cover in Liaoning Province.</p>
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<p>Methodological framework used to construct and integrate ecological network.</p>
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<p>Stepwise integration model of ecological network of basic ecological network and supplementary ecological network.</p>
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<p>Distribution and classification of ecological sources.</p>
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<p>Resistance surface of every factor and modified comprehensive resistance surface. (<b>a</b>) represents the resistance surface of DEM; (<b>b</b>) represents the ecological risk index based on the land cover; (<b>c</b>) represents the resistance surface of land cover; (<b>d</b>) represents the resistance surface of vegetation coverage; (<b>e</b>) represents the resistance surface of the slope; and (<b>f</b>) represents the modified resistance surface.</p>
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<p>Spatial patterns of optimization of a basic ecological network.</p>
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<p>Spatial patterns of integration of two types of ecological network. (<b>a</b>) represents the integration of the basic ecological network and level 1 supplementary ecological network; (<b>b</b>) represents the integration of the basic ecological network and level 2 supplementary ecological network; (<b>c</b>) represents the integration of the basic ecological network and level 2 supplementary ecological network.</p>
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<p>Spatial patterns of integration of all ecological networks.</p>
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<p>Regulation strategies with ecological sources.</p>
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19 pages, 13916 KiB  
Article
Hole Appearance Constraint Method in 2D Structural Topology Optimization
by Lei Zhu, Tongxing Zuo, Chong Wang, Qianglong Wang, Zhengdong Yu and Zhenyu Liu
Mathematics 2024, 12(17), 2645; https://doi.org/10.3390/math12172645 - 26 Aug 2024
Viewed by 818
Abstract
A 2D topology optimization algorithm is proposed, which integrates the control of hole shape, hole number, and the minimum scale between holes through the utilization of an appearance target image. The distance between the structure and the appearance target image is defined as [...] Read more.
A 2D topology optimization algorithm is proposed, which integrates the control of hole shape, hole number, and the minimum scale between holes through the utilization of an appearance target image. The distance between the structure and the appearance target image is defined as the hole appearance constraint. The appearance constraint is organized as inequality constraints to control the performance of the structure in an iterative optimization. Specifically, hole shapes are controlled by matching adaptable equivalent shape templates, the minimum scales between holes are controlled by a hole shrinkage strategy, and the hole number is controlled by a hole number calculation and filling method. Based on the SIMP interpolation topology optimization model, the effectiveness of the proposed method is verified through numerical examples. Full article
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<p>Optimization algorithm flowchart for hole appearance constraints.</p>
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<p>Image processing and hole information extraction. (<b>a</b>) Grayscale Image. (<b>b</b>) Binary Image. (<b>c</b>) Hole Information Image. (<b>d</b>) Enclosed Solid Regions. (<b>e</b>) Boundary Image of Solid Regions.</p>
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<p>Effectiveness of the MBR algorithm for holes. The red box represents the MBR of each hole.</p>
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<p>Example of similarity measurement methods for three equivalent shapes of holes. (<b>a</b>) Hole shape. (<b>b</b>) Rectangularity measurement method. (<b>c</b>) Ellipticity measurement method. (<b>d</b>) Isosceles triangle measurement method.</p>
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<p>Relationship between shape parameters of equivalent shapes and aspect ratio. The red box represents the the MBR of equivalent shape. (<b>a</b>) The relationship between the parameters of a rectangle and its aspect ratio. (<b>b</b>) The Relationship between Elliptical Parameters and Aspect Ratio. (<b>c</b>,<b>d</b>) The two relationships between the parameters and aspect ratio of isosceles triangles.</p>
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<p>Method for determining the angle <math display="inline"><semantics> <mrow> <mover accent="true"> <mrow> <mi>θ</mi> </mrow> <mo stretchy="false">^</mo> </mover> </mrow> </semantics></math> of the equivalent shape. The red box represents the equivalent rectangle of the shape.</p>
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<p>Example of hole shapes and their <math display="inline"><semantics> <mrow> <mi>T</mi> <mi>r</mi> </mrow> </semantics></math>, <math display="inline"><semantics> <mrow> <mi>R</mi> <mi>e</mi> </mrow> </semantics></math>, <math display="inline"><semantics> <mrow> <mi>E</mi> <mi>l</mi> </mrow> </semantics></math> values. The red box represents the equivalent shape.</p>
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<p>Hole filling method. (<b>a</b>) Binary image of structure. (<b>b</b>) The appearance target image obtained by filling an extra hole.</p>
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<p>Generating appearance targets through mapping equivalent shapes to a fixed grid. (<b>a</b>) The MES of each hole. The red box represents the equivalent shape of each hole. (<b>b</b>) Solid region after hole filling. (<b>c</b>) Visual representation of the target image. The red box represents the equivalent shape of the hole corresponding to the structure in (<b>a</b>).</p>
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<p>Schematic diagram of mitigating hole interference and minimum distance between cavities using hole shrinking strategy. (<b>a</b>) The grayscale image. (<b>b</b>) Binary image of structure. (<b>c</b>) The MES of each hole. The red box represents the equivalent shape of each hole. (<b>d</b>) The appearance target image. (<b>e</b>) Expand the holes in the appearance target image. (<b>f</b>) Updated appearance target image by hole shrinking strategy.</p>
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<p>Design domain and optimization results. (<b>a</b>) Design domain. (<b>b</b>) The structure obtained in the first phase of our optimization algorithm.</p>
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<p>Results of hole regularization for different values of <math display="inline"><semantics> <mrow> <msup> <mrow> <mi>A</mi> </mrow> <mrow> <mi mathvariant="normal">*</mi> </mrow> </msup> </mrow> </semantics></math>.</p>
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<p>The change in compliance, volume fraction, and appearance constraint during the iteration process. (<b>a</b>) The change in compliance changes during the iteration process. (<b>b</b>) The change in volume fraction and appearance constraint during the iteration process. The blue line represents the volume fraction, and the orange line represents the appearance constraint.</p>
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<p>Optimization results using single shape templates. (<b>a</b>) Isosceles triangle template. (<b>b</b>) Rectangle template. (<b>c</b>) Ellipse template.</p>
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<p>Design domain and optimization results. (<b>a</b>) Design domain. (<b>b</b>) Structure gray image.</p>
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<p>Effects of different minimum distance constraints between holes. The structure within the large red circle represents the enlarged structure within the small red circle.</p>
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<p>The change in compliance, volume fraction, and appearance constraints during the iteration process. (<b>a</b>) The change in compliance during the iteration process when k takes different values. (<b>b</b>) The change in volume fraction during the iteration process when k takes different values. (<b>c</b>) The change in appearance constraints during the iteration process when k takes different values.</p>
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<p>The effect of hole regularization under different hole quantity constraints.</p>
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<p>Volume fraction and appearance constraint during the iteration process for <math display="inline"><semantics> <mrow> <mover accent="true"> <mrow> <mi>m</mi> </mrow> <mo>¯</mo> </mover> <mo>=</mo> <mn>2</mn> </mrow> </semantics></math>. At the 33rd iteration, the number of holes reaches 4, and the optimization process transitions into the second stage, where appearance constraint is applied. The blue line represents the volume fraction, and the orange line represents the appearance con-straint.</p>
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<p>The optimization outcomes for the MBB beam case study.</p>
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23 pages, 1362 KiB  
Article
Joint Optimization of Service Migration and Resource Allocation in Mobile Edge–Cloud Computing
by Zhenli He, Liheng Li, Ziqi Lin, Yunyun Dong, Jianglong Qin and Keqin Li
Algorithms 2024, 17(8), 370; https://doi.org/10.3390/a17080370 - 21 Aug 2024
Viewed by 1414
Abstract
In the rapidly evolving domain of mobile edge–cloud computing (MECC), the proliferation of Internet of Things (IoT) devices and mobile applications poses significant challenges, particularly in dynamically managing computational demands and user mobility. Current research has partially addressed aspects of service migration and [...] Read more.
In the rapidly evolving domain of mobile edge–cloud computing (MECC), the proliferation of Internet of Things (IoT) devices and mobile applications poses significant challenges, particularly in dynamically managing computational demands and user mobility. Current research has partially addressed aspects of service migration and resource allocation, yet it often falls short in thoroughly examining the nuanced interdependencies between migration strategies and resource allocation, the consequential impacts of migration delays, and the intricacies of handling incomplete tasks during migration. This study advances the discourse by introducing a sophisticated framework optimized through a deep reinforcement learning (DRL) strategy, underpinned by a Markov decision process (MDP) that dynamically adapts service migration and resource allocation strategies. This refined approach facilitates continuous system monitoring, adept decision making, and iterative policy refinement, significantly enhancing operational efficiency and reducing response times in MECC environments. By meticulously addressing these previously overlooked complexities, our research not only fills critical gaps in the literature but also enhances the practical deployment of edge computing technologies, contributing profoundly to both theoretical insights and practical implementations in contemporary digital ecosystems. Full article
(This article belongs to the Collection Feature Papers in Algorithms for Multidisciplinary Applications)
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<p>An example of an MECC environment.</p>
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<p>An example of the migration process.</p>
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<p>Training of A2C-based dynamic migration and resource allocation algorithm.</p>
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<p>The impact of the number of ESs on average response delay.</p>
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<p>The impact of the number of ESs on failure rate.</p>
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<p>The impact of the time constraint on average response delay.</p>
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<p>The impact of the time constraint on failure rate.</p>
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<p>The impact of the number of users on average response delay.</p>
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<p>Decision-making duration for each step.</p>
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<p>The impact of the number of users on failure rate.</p>
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<p>The impact of data size on average response delay.</p>
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<p>The impact of data size on average failure rate.</p>
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<p>The impact of network scale expansion in an environment with 40 users and 20 ESs. (<b>a</b>) Average response delay. (<b>b</b>) Average failure rate.</p>
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21 pages, 34151 KiB  
Article
Analyzing Spatial Dependence of Rice Production in Northeast Thailand for Sustainable Agriculture: An Optimal Copula Function Approach
by Suneerat Srisopa, Peerapong Luamka, Saowanee Rattanawan, Khanitta Somtrakoon and Piyapatr Busababodhin
Sustainability 2023, 15(20), 14774; https://doi.org/10.3390/su152014774 - 11 Oct 2023
Viewed by 2268
Abstract
Rice is not only central to Thailand’s economy and dietary consumption but also plays a significant role in global food security. Northeast Thailand, in particular, is a principal region for rice cultivation. However, with the mounting concerns of climate change, it becomes paramount [...] Read more.
Rice is not only central to Thailand’s economy and dietary consumption but also plays a significant role in global food security. Northeast Thailand, in particular, is a principal region for rice cultivation. However, with the mounting concerns of climate change, it becomes paramount to understand the interplay between regional weather patterns and rice yields, aiming to develop effective adaptive agricultural strategies. The current study aimed to fill the research gap by investigating an optimal copula for the spatial dependence of rice production and related meteorological variables in this area. The objective of this study is to understand how rice production in different areas relates to each other in order to improve farming practices and address challenges such as suitable weather. To achieve this goal, we apply three families of copulas—elliptical, Archimedean, and extreme—to analyze crop and meteorological variables across the watershed in the northeastern region of Thailand. With a data foundation extending from 1981 to 2021 from the Regional Office of Agricultural Economics Sector 4, Thailand, this study offers a comprehensive analysis of the spatial dynamics driving rice production across twenty provinces in Northeast Thailand. Using a piecewise linear model, we dissected rice yield trends, revealing distinct slopes in production and yield across various periods. The analysis leaned on elliptical, Archimedean, and extreme copula families, using the maximum likelihood estimation to discern marginal distribution residuals. Through rigorous bootstrap goodness-of-fit tests and cross-validation, the most appropriate copula for each province was identified. Key findings demonstrate pronounced spatial interdependencies in rice yields, with the Frank copula prominently capturing the product relationship between provinces such as Maha Sarakham and Roi-Et. Conversely, the Clayton copula better characterized regions such as Srisaket and Ubon Ratchathani. Moreover, the results underscore the considerable influence of meteorological factors, notably rainfall and temperature, on rice production, especially in regions like Ubon Ratchathani. In distilling these multifaceted relationships, the study charts a pathway for crafting sustainable, localized agricultural strategies. As the world grapples with climate change’s ramifications, the insights from this research stand crucial, offering direction for fostering resilience, adaptation, and optimizing rice productivity across Thailand’s diverse agrarian landscapes. Full article
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<p>Land use map of the northeastern region of Thailand.</p>
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<p>Box-plot illustrating key meteorological metrics for the Northeast (1981–2021): (<b>a</b>) mean rainfall (mm), (<b>b</b>) mean temperature (°C), (<b>c</b>) total rainfall accumulation (mm), and (<b>d</b>) mean relative humidity (%).</p>
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<p>Changes in rice yield from 1981 to 2021 in two combinations of productivity and area for wet seasons with segmented regression lines at Ubon Ratchathani province. Symbols * and *** denote significance levels of 0.05 and 0.001, respectively.</p>
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<p>Comparison of rice production and yield for Ubon Ratchathani Province. (<b>a</b>) Rice production and cultivation areas from 1991 to 2021. (<b>b</b>) Evolution of rice production and yield over the period 1981 to 2021. Symbols *, **, and *** denote significance levels of 0.05, 0.01, and 0.001, respectively.</p>
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<p>Comparison of rice production and yield for Ubon Ratchathani Province. (<b>a</b>) Rice production and cultivation areas from 1991 to 2021. (<b>b</b>) Evolution of rice production and yield over the period 1981 to 2021. Symbols *, **, and *** denote significance levels of 0.05, 0.01, and 0.001, respectively.</p>
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<p>Comparison of rice production and yield for Udonthani Province. (<b>a</b>) Rice production and cultivation areas from 1991 to 2021. (<b>b</b>) Evolution of rice production and yield over the period 1981 to 2021. Symbols * and *** denote significance levels of 0.05 and 0.001, respectively.</p>
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<p>Comparison of rice production and yield for Udonthani Province. (<b>a</b>) Rice production and cultivation areas from 1991 to 2021. (<b>b</b>) Evolution of rice production and yield over the period 1981 to 2021. Symbols * and *** denote significance levels of 0.05 and 0.001, respectively.</p>
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<p>Comparison of rice production and yield for Roi-Et province. (<b>a</b>) Rice production and cultivation areas from 1991 to 2021. (<b>b</b>) Evolution of rice production and yield over the period 1981 to 2021. Symbols ** and *** denote significance levels of 0.01 and 0.001, respectively.</p>
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<p>Comparison of rice production and yield for Roi-Et province. (<b>a</b>) Rice production and cultivation areas from 1991 to 2021. (<b>b</b>) Evolution of rice production and yield over the period 1981 to 2021. Symbols ** and *** denote significance levels of 0.01 and 0.001, respectively.</p>
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<p>Comparison of rice production and yield for Burirum province. (<b>a</b>) Rice production and cultivation areas from 1991 to 2021. (<b>b</b>) Evolution of rice production and yield over the period 1981 to 2021. Symbols * and *** denote significance levels of 0.05 and 0.001, respectively.</p>
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<p>Comparison of rice production and yield for Burirum province. (<b>a</b>) Rice production and cultivation areas from 1991 to 2021. (<b>b</b>) Evolution of rice production and yield over the period 1981 to 2021. Symbols * and *** denote significance levels of 0.05 and 0.001, respectively.</p>
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<p>Relationship of yields (kg/ha) across regions.</p>
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<p>Association between crop data and meteorological variables in Ubon Rachathani province.</p>
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<p>Comparison of empirical copulas and fitted copula between Maha Sarakham and Roi-Et province.</p>
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<p>Comparison of empirical copulas and fitted copula between yields and meteorological data at Ubon Ratchathani province. (<b>a</b>) Yield and average rainfall (mm), (<b>b</b>) Yield and average temperature (°), (<b>c</b>) Yield and cumulative rainfall (mm) and (<b>d</b>) Yield and relative humidity (%).</p>
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