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71.
Data on mean wind pressure distribution on opposite walls of a five storey building model with smooth surface and also with balconies mounted thereon have been presented, and the effect of balconies on ventilation inducing wind forces has been discussed. It is shown that provision of balconies alters wind pressure distribution on windward wall but does not introduce significant change in it on the leeward side. Ventilative force across openings located centrally on opposite walls also remains almost unchanged due to the balconies. However, the ventilative forces across windows located at different heights on the windward wall only, get diminished at all the floors near the upstream end for obliquely incident wind, and over the entire wall width at the intermediate floors for the wind incidence at 90 ° angle on the wall. Enhancement in the ventilation inducing wind forces is caused at the top floors on the downstream side for obliquely incident wind, and near the ends of the wall at the ground and top floors for the wind impinging at right angle on the wall. 相似文献
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Satish Chand Bijendra Kumar Hari Om 《Journal of Network and Computer Applications》2009,32(3):660-665
In the request-based scheme, a patching channel is initiated on arrival of a request in an interarrival time of two adjacent multicast channels. If two requests are received in a short duration in an interarrival time, two patching channels are needed to service them. Both these channels deliver almost the same data, thus, wasting the bandwidth. This problem may be addressed in two ways: using higher level patching technique, or forcing the first request to wait for the second one. Using higher level patching technique makes the system more complex and thus usually not preferred. In the second case, the bandwidth usage certainly reduces, but the length of the waiting time by the first request for the second request is the main issue. In this paper, this issue is addressed by dividing the video duration into uniform time slots such that there is at least one request in a time slot for initiating the patching channel. The proposed scheme is named as Video Data Delivery using Slotted Patching. In this scheme, the patching channels download much less video data than the request-based scheme and thus require less bandwidth. This scheme may not provide immediate services to all users unlike the request-based scheme, but the user's waiting can be made arbitrarily small without using much resources unlike the request-based scheme. 相似文献
75.
C Rumi S Rutella L Teofili B Etuk E Ortu La Barbera G Micciulli MT Voso G Leone 《Canadian Metallurgical Quarterly》1997,25(3):246-251
OBJECTIVE: The purpose of this study was to differentiate between the catabolic effects of interleukin-1 (IL-1) when infused into the central nervous system or into the periphery. SUMMARY BACKGROUND DATA: After injury and infection, IL-1 has been found in the central nervous system. Chronic intracerebrovascular infusion of IL-1 produces protein catabolism, anorexia, and fever. However, IL-1 may act directly on liver and bone marrow to elicit metabolic responses. Although IL-1 is thought to be involved in a number of metabolic responses associated with injury-inflammation, the sites of action are unclear. METHODS: Rats were implanted with chronic infusion pumps and received diluent or three doses of IL-1 infused subcutaneously for 6 days, and a variety of response variables were measured. In a second study, doses were adjusted so that similar systemic catabolic responses were obtained from peripheral and intracerebroventricular infusion of IL-1. The acute-phase responses then were compared in the two groups of animals receiving IL-1 by different routes. RESULT: Subcutaneously infused IL-1 elicited catabolic responses in a dose-response manner. Similar catabolic responses were achieved by infusing one tenth of the dose of IL-1 given subcutaneously into the central nervous system. Although similar systemic responses (protein catabolism, anorexia, fever, and weight loss) were observed with both routes of infusion, the subcutaneous infusion produced a much greater lymphocytosis, elevation in acute-phase reactants, and fall in serum iron and albumin. CONCLUSIONS: The IL-1 appears to have different effects depending on the site of production and site of action. Regionalization of signal proteins such as IL-1 should be taken into consideration when devising specific anticytokine treatment strategies. 相似文献
76.
Rao K. Srinivasa Madhuri T. Krishna Leela Sairam T. Manish Vali Shaik Shoukath Chand Ch. Gopi Sravani K. Girija 《Microsystem Technologies》2022,28(12):2697-2704
Microsystem Technologies - In this paper, we have designed and simulations of RF MEMS shunt switch. The electro-mechanical and electromagnetic analysis of the switch have been done using COMSOL... 相似文献
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Jagdish Chand Gagan KumarPawan Kumar S.K. SharmaM. Knobel M. Singh 《Journal of Alloys and Compounds》2011,509(40):9638-9644
MgGdxFe2−xO4 (x = 0.0, 0.05, 0.1 and 0.15) ferrites, with improved dc resistivity, initial permeability, saturation magnetization, and extremely low relative loss factor, have been synthesized by solid state reaction technique. The microstructures, electric, dielectric and magnetic properties have been investigated by means of X-ray diffraction, Keithley 2611 system, impedance analyzer and VSM respectively. The addition of Gadolinium in Mg ferrite has been shown to play a crucial role in enhancing the electric, dielectric and magnetic properties. The dc resistivity is increased by two orders of magnitude as compared to Mg ferrite. Saturation magnetization has been increased by two times and remnant magnetization has been increased by more than three times due to the doping of Gd3+ ions in Mg ferrite. The relative loss factor was found to have very low values and is of the order of 10−4-10−5 in the frequency range 0.1-30 MHz. The variations of electric, dielectric and magnetic properties of the samples have been studied as a function of frequency and Gd3+ ions concentration measured at room temperature. High resistivity and improved magnetic properties can be correlated with better compositional stoichiometry and the replacement of Fe3+ ions by Gd3+ ions. The mechanisms responsible to these results have been discussed in this paper. 相似文献
79.
Kazuo Yamaura Masayoshi Suzuki Minako Yamamoto Rumi Shimada Tetsuya Tanigami 《应用聚合物科学杂志》1995,58(10):1787-1791
The light transmittance of the gels of poly(vinyl alcohol) (PVA)/phenol/water solutions was examined for the entire range of phenol/water content. Excellent transparency was found for the gels with phenol contents of 70–95 vol %. In full consideration of the results for the transparency and melting temperature of the gels and the viscosity and gelation ability of solutions, the PVA solutions of 75 vol % phenol content were selected for the gel spinning. The maximum dynamic moduli of drawn filaments at 25°C (room temperature) were 42 GPa (15x) for atactic PVA and 45 GPa (14x) for syndiotacticity-rich PVA. © 1995 John Wiley & Sons, Inc. 相似文献
80.
G. T. Adylov N. A. Kulagina G. S. Menosmanova M. Kh. Rumi Sh. A. Faiziev 《Glass and Ceramics》2007,64(11-12):413-415
A technology has been developed for manufacturing ceramogranite from natural materials found in Uzbekistan. The processes occurring during heat treatment of porcelain stone from the Boinaksaiskoe deposits have been investigated. The optimal calcination temperature, the composition of the ceramic paste, and the effect of individual components of the batch on the properties of ceramogranite have been determined. The kinetics of sintering of experimental pastes has been studied. It is shown that combining different types of mineral raw materials makes it possible to obtain ceramogranite with high thermomechanical characteristics. 相似文献