Rope

In a number of professions, human life hangs on a knotted rope. However, until now only a poor attention of scientists has been paid to the properties of knots. The main objective of the presented research is to provide an in-depth revision of commonly used loop knot efficiencies employing modern experimental technologies and correct statistical processing. In the first part of the paper, the common mistakes in the available information sources were pointed out and the correct way of assessing the loop knot efficiency was proposed. Subsequently, correct statistical calculus was derived to evaluate mean knot efficiency and confidence interval. Efficiencies of eight commonly used loop knots loaded in several geometries were precisely measured, evaluated, and analyzed. Special attention was paid to avoid misleading conclusions based on experiments of low statistical power. Loop knot efficiency is not a constant, but it depends at least on the static breaking strength of a rope. The process of knot breakage was recorded by high-speed infrared thermal imaging. Analyses showed that the temperature of the most exposed parts of a knot could reach polyamide melting point. Finally, the microfilament analysis using electron microscopy was carried out to understand the breakage process on the microscopic level. topics: knot efficiency, rope, tensile tests, thermal imaging, electron microscopy

Excavation of the 9th-century AD shipwreck B in Tantura Lagoon, Israel, yielded four toggles, numerous rope fragments, and three pierced wooden spatulate objects believed to be associated with the ship's rigging. In the first half of the article, the toggles are described and compared to a corpus of similar devices found on both land and shipwreck sites. The spatulate devices are tentatively identified as spill-toggles, pierced for attaching a trip-line. The second half of the article traces the textual and iconographical evidence for toggles and sail types––in particular, the lateen––in the ancient Mediterranean, and their possible association.

... first lead stock mould on a wooden core was found in the La Chrétienne C shipwreck, from the ... Anchor A dated to late Iron-Persian period, and anchor B to the Hellenistic-Early Roman periods. ... period, or one from the beginning of the 1st century AD, the Roman (Second Temple ...

Groins are popular river training structures widely used all over the world including Bangla- desh. Groins have been used to create a flow condition that reduces the vulnerability of river bank erosion by diverting the flow away from the bank. Also groins have been used to increase the navigability of waterways. The flow structures around groin head play a very important role for their successful performance. Literature search reveals that bell mouth groins are relatively more popular in Bangladesh than other types of groins. But no systematic experiments have been conducted to study the flow pattern and flow behavior around bell mouth groins. Keeping this in view, a study was undertaken to investigate the flow field around bell mouth groin in a large mobile bed physical model facility (46m x 11 m) of BUET. A total number of 24 test runs were conducted. Three different discharges and four different angles and two groin conditions (submerged and non-submerged) was considered. Twelve ...

The step-topped, free-standing square monument called in modern literature the Broken Obelisk was found by Hormuzd Rassam at Nineveh, near the Ishtar temple on the mound of Kuyunjik. It is the earliest monument of this kind, and it differs in its pictorial rendering from the later, so-called Assyrian obelisks. Whereas the succeeding examples display reliefs on their four sides, creating consecutive narratives, the Broken Obelisk exhibits a single, motionless relief on its front, the subject of the present paper (Börker-Klähn 1982, Nos. 132, 138–45, 152; Bär 1996, 57-68, 88–99, 101–5, 148–65).My aim here is to shed light on the motif of the king holding prisoners of war by means of lead ropes and to examine the bearing of this motif on the status of the royal image in pictorial renderings. According to different interpretations of the scene, the king holds a ring and rod (Börker-Klähn 1982, 178, No. 131 with earlier bibliography), or a ceremonial mace (Russell 2003, 4) as well as lea...

A summary history of ropemakers in Victorian, Australia; focussing on Donaghy's ropeworks Geelong, with reference to Kinnear's ropeworks, Footscray, Millers Ropeworks Brunswick and Yarraville and A.C. Downs/Samson Cordage Works and Wolfe's Cordage Works both also in Brunswick.