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Investigation of Rectangular and U-Shaped Labyrinth Weirs  [cached]
M. Heidarour,S. F. Mousavi,A. R. Roushani Zarmehri
Journal of Science and Technology of Agriculture and Natural Resources , 2006,
Abstract: Because of slight variation of the static head due to discharge fluctuations, the labyrinth weirs are considered to be economical structures for flood control and water level regulation in irrigation networks, as compared to other devices. Labyrinth weirs are composed of folded sections observed as trapezoidal and triangular in plan view. In this study, rectangular and U-shaped labyrinth weirs were investigated. Experiments were conducted on 15 labyrinth weir models. The models included eight rectangular labyrinth models and six U-shaped labyrinth models with different heights and lengths, and one linear model. All the experiments were performed in a horizontal rectangular flume, 7 m long, 0.32 m wide and 0.35 m high. The results indicated that for all the models, discharge coefficient increased sharply with an increase in Ht/P and attained a maximum value. This coefficient then decreased smoothly with a further increase in Ht/P. Increasing height of weirs increased the discharge coefficient for both rectangular and U-shaped weirs. The results also showed that increasing the length parallel to the flow direction decreased and increasing the length perpendicular to the flow direction increased the discharge coefficient. Generally, the discharge coefficient for rectangular weir was less than that of the U-shaped weir. The obtained results compared with those of Tullis et al. (1995) showed that discharge coefficient for U-shaped weir is more and for rectangular weir is less than that of the trapezoidal weir for angle of the side legs of 8 and 12 degrees.
Crossed modules of racks  [PDF]
Alissa S. Crans,Friedrich Wagemann
Mathematics , 2013,
Abstract: We generalize the notion of a crossed module of groups to that of a crossed module of racks. We investigate the relation to categorified racks, namely strict 2-racks, and trunk-like objects in the category of racks, generalizing the relation between crossed modules of groups and strict 2-groups. Then we explore topological applications. We show that by applying the rack-space functor, a crossed module of racks gives rise to a covering. Our main result shows how the fundamental racks associated to links upstairs and downstairs in a covering fit together to form a crossed module of racks.
Guy Roger Biyogmam
Mathematics , 2011,
Abstract: In this paper, we introduce the category of Lie $n$-racks and generalize several results known on racks. In particular, we show that the tangent space of a Lie $n$-Rack at the neutral element has a Leibniz $n$-algebra structure. We also define a cohomology theory of $n$-racks..
Foundations of topological racks and quandles  [PDF]
Mohamed Elhamdadi,El-ka?oum M. Moutuou
Mathematics , 2015,
Abstract: We give a foundational account on topological racks and quandles. Specifically, we define the notions of ideals, kernels, units, and inner automorphism group in the context of topological racks. Further, we investigate topological rack modules and principal rack bundles. Central extensions of topological racks are then introduced providing a first step towards a general continuous cohomology theory for topological racks and quandles.
trash epoch эпоха трэш  [cached]
Elena Grigoryeva
Project Baikal , 2012,
Abstract: Unconventionally, the editorial of this issue begins with two epigraphs: trash 1. foolish ideas or talk; nonsense; 2. Chiefly US and Canadian useless or unwanted matter or objects; 3. a literary or artistic production of poor quality; 4. Chiefly US and Canadian a poor or worthless person or a group of such people. [Collins English Dictionary] You got to make good out of bad. That's all there is to make it with. Robert Penn Warren, “All the King’s Men”. But before talking about the topic of the issue, we should pay off the debt. The previous (double) issue was completely devoted to Irkutsk’s jubilee. We will fill in the gaps and look back on the events of the past year missed by PB. There are a lot of them: the UIA Congress in Tokyo (5-7), the Zodchestvo Festival and the UAR Plenary Meeting in Moscow (16-29), the review competition of graduation works in Erevan (30–39) and Les Ateliers of Urban Planning and Development in Cergy-Pontoise (48–54). The New Year’s news blends into the topic of the issue. This year in Irkutsk discarded Christmas trees began to be recycled into fertilizer. In the Kemerovo region the old Christmas trees are used as food for cows. So the supercilious attitude toward trash is no longer relevant. In the future we shall eat it; actually, we are already eating it. Artists help us adjust to the idea that we will live in the global dump. Trash Muses inspired Zhenya Kraineva and Konstantin Lidin to a diptych about trash art (66–75). The first essential step in waste recycling is to change our view on waste. In people’s minds the dump is turned into a deposit of valuable resources. The detailed text by Andrei Ivanov (90–99) tells us about a slum district obtaining a new status and turning into a historical heritage. It is very urgent to convert trash into resources. On the Earth, mountains of garbage grow twice as fast as the population. 17% of homes in Sweden are heated with garbage. Japan processes 96% of waste, Germany 95%, Poland 16%, Russia only 5%. At this moment the territory of Russia has accumulated 100 billion tons of garbage – there is scarcely any deposit of such a large scale. Waste recycling plants are a vital task for today’s and tomorrow’s architecture (102–105). The architecture itself is no longer designed for centuries. The green standards contain such an essential item as engineering redesign for dismantled or demolished structures. Instead of the philosophical principle “my house is my fortress”, the impermanence is on the agenda today. A house, like a short-life packing or tomorrow’s garbage, is now under the statem
Rectangular Patch Antenna Performances Improvement Employing Slotted Rectangular shaped for WLAN Applications
Mouloud Challal,Arab Azrar,Mokrane Dehmas
International Journal of Computer Science Issues , 2011,
Abstract: This paper describes the effect of inserting a rectangular shape defected ground structure (DGS) into the ground plane of the conventional rectangular microstrip patch antenna (CRMPA). The performances of the CRMPA are characterized by varying the dimensions of the rectangular slot (RS-DGS) and also by locating the RS-DGS at specific position. Simulation results have verified that the CRMPA including RS- DGS had improved the CRMPA without RS-DGS. The return loss (RL) enhances approximately of 100 %, and gain improvement of 0.8 dB.
Rectangular C-Shaped Slot Microstrip Antenna for Linear Polarization
Girraj Sharma,Kaluram Maholia,Pankaj Jangid
International Journal of Electronics and Computer Science Engineering , 2012,
Abstract: The design of a rectangle microstrip antenna with Linear polarization (LP) is presented. To compact the antenna size and overcome the high impedance problem, the LP antenna is excited by a co-axial cable. Several prototypes of the squarering LP antennas with various substrate thicknesses (0.75mm_ultralam2000 and 1.56mm_rt_duroid3003) have been constructed and studied experimentally. The simple rectangular and compact C shaped microstrip antenna is simulated with IE3D and MATLAB and their corresponding result is compared.
Theoretical Determination and Experimental Verification of Transport Index of Rectangular Shaped Radioactive Containers  [PDF]
Khalid Jamil, Muhammad Asim, Majid Irfat, Shahid Manzoor
World Journal of Nuclear Science and Technology (WJNST) , 2014, DOI: 10.4236/wjnst.2014.42012

Ionizing radiations are widely used to sustain and enhance our quality of life in the areas such as medical diagnosis, therapy, scientific research and industry etc. Ionizing radiations are available from radioactive sources which are made of radioactive materials. The radioactive materials are produced in either nuclear power or research reactors or nuclear accelerators or extracted from the naturally found radioactive ores. These radioactive sources and radioactive materials need to be transported from their places of production to the places of applications and finally to waste repositories. The radioactive materials are transported in well designed packages having various shapes and sizes. In the field of radioactive transport, it is a mandatory to find the Transport Index (TI) to be mentioned on each package for transportation. This research is focused on the determination of the maximum γ-ray radiation dose at one meter from the surface of cubic and rectangular shaped package or containers. A computer code “Solid Angle for Transport Index” (SAFTI) has been developed using MATLAB to determine the location of maximum value of the radiation dose rate from the surface of a rectangular or square container. This maximum dose rate is used to determine the transport index. Some of the results of the code have been compared with the experimental results. The results of this research are useful not only to determine TI for individual packages but also to find the TI of the vehicles carrying the transport packages.

Complete wetting near an edge of a rectangular-shaped substrate  [PDF]
Alexandr Malijevsky
Physics , 2014, DOI: 10.1088/0953-8984/26/31/315002
Abstract: We consider fluid adsorption near a rectangular edge of a solid substrate that interacts with the fluid atoms via long range (dispersion) forces. The curved geometry of the liquid-vapour interface dictates that the local height of the interface above the edge $\ell_E$ must remain finite at any subcritical temperature, even when a macroscopically thick film is formed far from the edge. Using an interfacial Hamiltonian theory and a more microscopic fundamental measure density functional theory (DFT), we study the complete wetting near a single edge and show that $\ell_E(0)-\ell_E(\delta\mu)\sim\delta \mu^{\beta_E^{co}}$, as the chemical potential departure from the bulk coexistence $\delta\mu=\mu_s(T)-\mu$ tends to zero. The exponent $\beta_E^{co}$ depends on the range of the molecular forces and in particular $\beta_E^{co}=2/3$ for three-dimensional systems with van der Waals forces. We further show that for a substrate model that is characterised by a finite linear dimension $L$, the height of the interface deviates from the one at the infinite substrate as $\delta\ell_E(L)\sim L^{-1}$ in the limit of large $L$. Both predictions are supported by numerical solutions of the DFT.
On Finite Racks and Quandles  [PDF]
Pedro Lopes,Dennis Roseman
Mathematics , 2004,
Abstract: We revisit finite racks and quandles using a perspective based on permutations which can aid in the understanding of the structure. As a consequence we recover old results and prove new ones. We also present and analyze several examples.
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