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Wireless Personal Communications - Routing is one of the most challenging task in mobile ad hoc networks. Several works have been proposed to address this challenge. Majority numbers of researchers... 相似文献
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Ahlam Ammar Sharif 《建筑学研究前沿(英文版)》2020,9(4):837-857
Urban researchers have maintained a constant interest in the complexity and continuity of urban space usage. Some have applied actor–network theory (ANT) to investigate the heterogeneity of spaces and present them through the networks of their users’ activities. However, these accounts are predominantly limited in examining the extent to which these spaces may be heterogeneous when exploring such networks. This paper draws on recent ANT scholarship, which employs an ethnographic research conducted in a main park in a housing project at Dahiyat Al Hussein in Amman, Jordan. The findings describe the complex and unpredictable negotiations that occur within spaces by documenting the varieties and interrelations among user activity networks within this common and shared urban space. This research reveals the extent to which spaces, parks in this case, may be heterogeneous by unpacking their usage. The conclusions and insights assert the necessity of paying attention to design detail and creating designs that are responsive to evolving user activities. 相似文献
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Open-pit deposits are often characterised by a stack of layers of different geological nature. Some layers are worthless while the ore of the others is of a varying economic value depending on grade. To reach a layer, it is necessary to have first removed the upper layers above the extraction zone. This action results in uncovering the layer in this particular place and in facilitating access to the layers below. This extraction process involves a series of 2–7 basic operations; each one is performed by a machine, some of which are able to perform up to three different operations. Ensuring the consistency of mining extraction scheduling over a few months, in order to meet known or forecast demand, is a challenging task. A mining extraction model based on mathematical programming is proposed but it is hardly usable, due to its size. Therefore, a model based on a Discrete Event Simulation, is created to test how ore supplies are affected by the tactical and operational decisions relating to the choice of parcels to be processed and to the allocation of machines to the different basic operations. 相似文献
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Taieb Aouak Abdulaziz Ali Alghamdi Ahlam Abdulrahman Alrashdi Mohamed Ouladsmane Zeid AlOthman 《分离科学与技术》2016,51(14):2440-2454
In order to improve the miscibility of poly(vinyl chloride)/polystyrene (PVC/PS) system and to use the prepared material as a membrane to separate benzene from benzene/cyclohexane mixture by pervaporation technique, two poly(styrene-co-N-vinylpyrrolidone) (PSVP) copolymers containing 6.67 and 13.55 mol% of N-vinylpyrrolidone (N-VP) contents were synthesized through a radical polymerization. A comparative study of the miscibility of the PVC/PSVP blends with different compositions was carried out using differential scanning calorimetry, viscosimetry and Fourier transform infrared spectroscopy methods in which the interaction parameters between the two components were widely investigated. To improve the pervaporative flux of PVC membrane to separate benzene from benzene/cyclohexane mixture, a preliminary test of swelling and sorption was performed on PVC/PSVP7 membranes using an azeotropic benzene/cyclohexane mixture. It was revealed that the PVC/PSVP7 membrane containing 10 wt% of PSVP7 showed the best performance and the diffusion behaviour of this mixture through PVC and PVC/PCVP7 membranes has a Fickian behaviour. The pervaporation parameters of this membrane support those of the swelling and selective sorption data and reveal that this membrane could enhance the total flux without significantly affecting its selectivity to benzene. 相似文献
5.
Mohsin Ahlam Hashim Zainal Anazida Bakar Kamalrulnizam Abu 《Wireless Personal Communications》2018,102(1):473-493
Wireless Personal Communications - During the last two decades, there has been a tremendous growth in the use of MANETs, not only due to the development of the technology but also due to their high... 相似文献
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This work investigates the possibility of utilizing the µp-8085 and its application to concrete crack depth evaluation. For the purpose of the nondestructive testing, ultrasonic pulses are of importance in assessing the quality of concrete as well as flaw detection and measurement. This will be useful in repairing concrete columns. 相似文献
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Ahlam M. J. Ali Zeki Y. Al-Saigh 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1980,30(1):440-446
Upon ultraviolet irradiation azobenzene and decafluoroazobenzene in cyclohexane and diethyl ether solutions decompose into phenylazo, phenylazomethylene and aniline radicals. The major products formed in cyclohexane solution are N-cyclohexylaniline, N-cyclohexylpentafluoroaniline, phenylazocyclohexane, pentafluorophenyl-azocyclohexane, 1-phenyl-2-cyclohexylhydrazine and 1-pentafluoro-2-cyclohexyl hydrazine. In diethyl ether solution the products are N-polymethylene phenylhydrazine, N-polymethylene pentafluorophenyl hydrazine, phenylhydrazine cyclohexane, pentafluorophenyl hydrazine cyclohexane and phenylazo-N-polymethylene. Minor products are also formed from the photosensitisation of solvent molecules. The primary and secondary reactions of the azobenzenes which lead to these products are discussed. 相似文献
8.
Milad Abdalrhman Hussein Sadaam Hadee Khekan Ahlam R. Rashid Mohammed Al-Msari Haitham Tran Tan Huy 《Engineering with Computers》2022,38(4):3625-3637
Engineering with Computers - Over the past few decades, it has been observed a remarkable progression in the development of computer aid models in the field of civil engineering. Machine learning... 相似文献
9.
Sasan Shadpour Ahlam Nemati Mirosaw Salamoczyk Marianne E. Prvt Jiao Liu Nicola J. Boyd Mark R. Wilson Chenhui Zhu Elda Hegmann Antal I. Jkli Torsten Hegmann 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(4)
The range of possible morphologies for bent‐core B4 phase liquid crystals has recently expanded from helical nanofilaments (HNFs) and modulated HNFs to dual modulated HNFs, helical microfilaments, and heliconical‐layered nanocylinders. These new morphologies are observed when one or both aliphatic side chains contain a chiral center. Here, the following questions are addressed: which of these two chiral centers controls the handedness (helicity) and which morphology of the nanofilaments is formed by bent‐core liquid crystals with tris‐biphenyl diester core flanked by two chiral 2‐octyloxy side chains? The combined results reveal that the longer arm of these nonsymmetric bent‐core liquid crystals controls the handedness of the resulting dual modulated HNFs. These derivatives with opposite configuration of the two chiral side chains now feature twice as large dimensions compared to the homochiral derivatives with identical configuration. These results are supported by density functional theory calculations and stochastic dynamic atomistic simulations, which reveal that the relative difference between the para‐ and meta‐sides of the described series of compounds drives the variation in morphology. Finally, X‐ray diffraction, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and atomic force microscopy (AFM) data also uncover the new morphology for B4 phases featuring p2/m symmetry within the filaments and less pronounced crystalline character. 相似文献
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