Fuel Management

The recent study of botanical macro-remains from the Late Sasanian and Early Islamic (5th to 8th century) fort of
Fulayj (Batinah, Sultanate of Oman) provides a unique opportunity to discuss food and fuel acquisition strategies
in an arid environment and to document periods that are little known from an archaeobotanical perspective in
Eastern Arabia. Seed assemblages include the first well-identified and directly radiocarbon dated evidence of
sorghum (Sorghum bicolor ssp. bicolor (L.) Moench.) in Eastern Arabia, which raises the question of whether the
grain was imported from distant sources (for example Yemen, East Africa or India) or locally cultivated. In
addition to sorghum, the food plant assemblage includes hulled barley (Hordeum vulgare), date (Phoenix dactylifera)
and jujube (Ziziphus cf. spina-christi). Date palm gardens may have existed near to the site as they do today
or food products may have been brought from date palm gardens on the Batinah coast where conditions for
agricultural production are particularly favourable. Charcoal analysis reveals that the main taxa used for fuel
(acacia, prosopis, jujube tree, tamarisk) were collected from local plant communities, occasionally supplemented
with firewood gathered in the foothills and mountainous areas.

The fuel used in hearths in the Upper Palaeolithic period and the management of this fuel have long given rise to questions on intentional or opportunistic human comportment. To understand how fuel was managed during the Aurignacian and Gravettian cultures, hearth samples from the French site of Abri Pataud (ca. 34–20 kyr BP) were collected. An image analysis method for the automated quantification of burnt particles from macroscopic-to-microscopic sediment fractions was developed, and the results obtained using this method were compared with the palaeoenvironmental data available close to the site. At Abri Pataud, the use of bones was dominant during the Pleniglacial, suggesting an intentional practice. However, environmental pressures could have influenced the fuel management practices of the hunter-gatherers, even if the dualistic relationship between the availability of firewood and the use of bone in hearths must be considered. Thus, burnt particle quantification provides more than just an observation of burnt macroremains in hearths: it relates to fundamental information on human behavior.

Preliminary studies have been performed to design a device for nuclear waste transmutation and hydrogen generation based on a gas-cooled pebble bed accelerator driven system, TADSEA (Transmutation Advanced Device for Sustainable Energy Application). In previous studies we have addressed the viability of an ADS Transmutation device that uses as fuel wastes from the existing LWR power plants, encapsulated in graphite in the form of pebble beds, cooled by helium which enables high temperatures (in the order of 1200 K), to generate hydrogen from water either by high temperature electrolysis or by thermochemical cycles. For designing this device several configurations were studied, including several reflectors thickness, to achieve the desired parameters, the transmutation of nuclear waste and the production of 100 MW of thermal power. In this paper new studies performed on deep burn in-core fuel management strategy for LWR waste are presented. The fuel cycle on TADSEA device has been analyzed based on both: driven and transmutation fuel that had been proposed by the General Atomic design of a gas turbine-modular helium reactor. The transmutation results of the three fuel management strategies, using driven, transmutation and standard LWR spent fuel were compared, and several parameters describing the neutron performance of TADSEA nuclear core as the fuel and moderator temperature reactivity coefficients and transmutation chain, are also presented.

Growing accumulations of fuel, changing climates, and residential development in forested landscapes have accelerated the risk of wildland fire, particularly in the western United States. The magnifying level of risk of fire in the urban–wildland interface requires multiple actors implementing coordinated fuel anagement, fire suppression, and community protection activities. The successful implementation of such actions is built upon trusting relationships in fire protection planning process. Trust is fundamental to cooperative human relationships and natural resource planning literature increasingly cites lack of trust as a major issue for plan implementation. This study of two community wildland fire protection planning processes revealed the importance of transparency in decisions, effective leadership, consensus on the framing of risk, and planning scale in affecting trust. Based on these results, five suggestions are offered as necessary conditions to promote effective communit...

The purpose of this research has been to develop an advanced Super-Nodal method to reduce the run time of 3-D core neutronics models, such as in the NESTLE reactor core simulator and FORMOSA nuclear fuel management optimization codes. Computational performance of the neutronics model is increased by reducing the number of spatial nodes used in the core modeling. However, as the number of spatial nodes decreases, the error in the solution increases. The Super-Nodal method reduces the error associated with the use of coarse nodes in the analyses by providing a new set of cross sections and ADFs (Assembly Discontinuity Factors) for the new nodalization. These so called homogenization parameters are obtained by employing consistent collapsing technique. During this research a new type of singularity, namely "fundamental mode singularity", is addressed in the ANM (Analytical Nodal Method) solution. The "Coordinate Shifting" approach is developed as a method to address...

Signifi cant advances in social science-based wildfi re research have occurred in the past fi ve years. Managers, policy makers, and researchers have worked to better understand the perspectives of homeowners, residents, tourists, and recreationists on fi re and fuels management and how to better involve them in the planning process. This research examines how the recreational usage of residents

Fuel and land management activities in the past century have placed wildland values such as soil and water quality at greater risk due to increased soil erosion. Eroded sediment can lead to decreased long-term soil productivity and adversely impact aquatic ecosystems. Higher runoff rates from severely burned landscapes can lead to flooding and increased risk to human life and property. Over the past ten years, we have completed studies on eight sites in the Northwest and Southeast U.S. measuring erosion impacts associated with prescribed burning. We are now carrying out field and laboratory studies addressing knowledge gaps in our understanding of fuel management practices on soil erosion, and developing a user-friendly computer interface to be able to evaluate the risk and consequences of erosion hazards following wildfires, mitigation treatments, and prescribed burns. Specific tasks that we are addressing include: determining hillslope characteristics that govern dry ravel process...

The amount of plutonium (Pu) isotopes and the resultant savings of 235U due to their production were calculated in the low enriched uranium (LEU) fuel, being utilized in Pakistan Research Reactor-1 (PARR-1). Further the importance map and relative importance map for different isotopes of Pu were also determined. Equilibrium PARR-1 core was achieved for these calculations. MTR-PC26 package was used to generate the microscopic cross-sections data for 45 elements including fissile/structural materials and also the fission products. Finite difference reactor core analysis code CITATION was employed for the fuel management analysis and static depletion calculations.The results indicated that PARR-1 core has attained its equilibrium state after eleven cycles with each cycle of duration about forty full power (10 MW) days. Further, the results showed that at the beginning of equilibrium cycle (BOEC) of the PARR-1 core, net reactivity addition due to all isotopes of Pu was 4.86 × 10−3Δk/k. Amount of 235U equivalent to this value of reactivity was found to be 15.58 ± 0.021 g. Plots of importance and relative importance maps predicted higher isotopic concentrations of Pu in the fuel elements located in the vicinity of central water box.