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91.
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An indirect forced convection and desiccant integrated solar dryer is designed and fabricated to investigate its performance under the hot and humid climatic conditions of Chennai, India. The system consists of a flat plate solar air collector, drying chamber and a desiccant unit. The desiccant unit is designed to hold 75 kg of CaCl2-based solid desiccant consisting of 60% bentonite, 10% calcium chloride, 20% vermiculite and 10% cement. Drying experiments have been performed for green peas at different air flow rate. The equilibrium moisture content Me is reached in 14 h at an air flow rate of 0.03 kg/m2 s. The system pickup efficiency, specific moisture extraction rate, dimensionless mass loss, mass shrinkage ratio and drying rate are discussed in this paper.  相似文献   
93.
Architects based the Intel 870 system architecture on the scalability port, a coherent system interconnect. The system's building-block approach lets a single chip set support a wide range of server segments.  相似文献   
94.
This paper examines various routes to achieving a 60% carbon emission reduction from the UK housing stock by 2050 compared to 1996, using a new object-oriented housing stock and carbon model, DECarb. As housing is at present responsible for 26% of all UK emissions, housing carbon reduction is likely to be a key component for the overall 60% emission reduction target set by the UK Government's Energy White Paper in 2003. This paper compares 3 independently published sets of scenarios detailing possible routes and suggests that highly disaggregated approaches produce more credible data. The results also show that whilst there are many different routes to achieving the target from a technological standpoint, all of them will require significant shifts in current practice. We investigate other routes to achieving this target, while also meeting nearer term reductions of 50% by 2030. DECarb shows that significant challenges exist in meeting these requirements, though they are technically feasible. On this basis it also becomes clear that the domestic sector will not be able to offset smaller reductions from any other sector of the economy.  相似文献   
95.
Several techniques of lumbar disk annulotomy have been described in clinical reports, but have not addressed the influence of annulotomy type on motion-segment stability. The technique used to incise during diskectomy may play a role in the subsequent healing and biomechanical stability of the disk. The purpose of this study is to develop a finite-element model using ADINA to study the influence of annulotomy-technique selection on disk competence. The analyses showed that both the box- and slit-type annular incisions produced similar changes in the biomechanical characteristics of the disk excepting the stresses in the disk annulus. The study also showed that there is no preference between the two annular incisions as far as post-surgical stability of the disk is concerned.  相似文献   
96.
An Occam filter employs lossy data compression to separate signal from noise. Previously, it was shown that Occam filters can filter random noise from deterministic signals. Here, we show that Occam filters can also separate two stochastic sources, depending on their relative compressibility. We also compare the performance of Occam filters and wavelet-based denoising on digital images  相似文献   
97.
This paper concerns the problem of assembling composite objects. We study the problem on two fronts; Firstly we consider the complexity of deciding the existence of an assembly sequence and show that this is PSPACE-hard in general. Secondly we define a new measure of complexity, one that attempts to measure the minimum number of hands required to assemble a given composite. We analyze various classes of composite objects with respect to this measure.  相似文献   
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We report for the first time a bidirectional optical backplane bus for a high performance system containing nine multi-chip module (MCM) boards, operating at 632.8 and 1300 nm. The backplane bus reported here employs arrays of multiplexed polymer-based waveguide holograms in conjunction with a waveguiding plate, within which 16 substrate guided waves for 72 (8×9) cascaded fanouts, are generated. Data transfer of 1.2 Gbt/s at 1.3-μm wavelength is demonstrated for a single bus line with 72 cascaded fanouts. Packaging-related issues such as transceiver size and misalignment are embarked upon to provide a reliable system with a wide bandwidth coverage. Theoretical treatment to minimize intensity fluctuations among the nine modules in both directions is further presented and an optimum design rule is provided. The backplane bus demonstrated, is for general-purpose and therefore compatible with such IEEE standardized buses as VMEbus, Futurebus and FASTBUS, and can function as a backplane bus in existing computing environments  相似文献   
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