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141.
An error tolerant hardware efficient verylarge scale integration (VLSI) architecture for bitparallel systolic multiplication over dual base, which canbe pipelined, is presented. Since this architecture has thefeatures of regularity, modularity and unidirectionaldata flow, this structure is well suited to VLSIimplementations. The length of the largest delay pathand area of this architecture are less compared to the bitparallel systolic multiplication architectures reportedearlier. The architecture is implemented using Austria Micro System's 0.35 μm CMOS (complementary metaloxide semiconductor) technology. This architecture canalso operate over both the dual-base and polynomialbase.  相似文献   
142.
Development of robust dynamical systems and networks such as autonomous aircraft systems capable of accomplishing complex missions faces challenges due to the dynamically evolving uncertainties coming from model uncertainties, necessity to operate in a hostile cluttered urban environment, and the distributed and dynamic nature of the communication and computation resources. Model-based robust design is difficult because of the complexity of the hybrid dynamic models including continuous vehicle dynamics, the discrete models of computations and communications, and the size of the problem. We will overview recent advances in methodology and tools to model, analyze, and design robust autonomous aerospace systems operating in uncertain environment, with stress on efficient uncertainty quantification and robust design using the case studies of the mission including model-based target tracking and search, and trajectory planning in uncertain urban environment. To show that the methodology is generally applicable to uncertain dynamical systems, we will also show examples of application of the new methods to efficient uncertainty quantification of energy usage in buildings, and stability assessment of interconnected power networks.  相似文献   
143.
144.
Coir (Cocos nucifera) is a natural fibre known to retain its strength and resist biodegradation far better than other industrial natural fibres. However, systematic studies in this discipline are scarce. Geotextiles are usually exposed to diverse pH, salinity, moisture, and microbial association conditions. In the present work, specific surface modifications of coir geotextiles using a natural agent (cashew nut shell liquid) have been carried out to enhance their long-term performance depending on the end applications. The modified and unmodified geotextiles were subjected to acidic, alkaline, and neutral pH conditions, saline conditions, alternate wetting and drying cycles, and thermal cycles for the assessment of their durability, measured in terms of tensile strength. In situ soil burial studies in a tropical climate were conducted in specially prepared soil to follow the biodegradation behaviour of geotextiles at various depths. The surface-modified geotextiles were found to resist adverse chemical, physical, and biological conditions much better than the unmodified geotextiles. Alkaline conditions marginally accelerated the degradation rates when compared to acidic environments. The saline conditions, as well as alternate wetting and drying conditions, resulted in marginal loss of tensile strength (<7%). The surface-modified geotextiles buried within lower depths of soil under field conditions retained 70–80% of their initial tensile strength after 12 months, whereas the unmodified geotextiles lost 88% strength in four months. The positive impact of surface modification on durability is confirmed by scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis. The results indicate the excellent potential of suitably surface-modified coir geotextiles for long-term use in adverse conditions.  相似文献   
145.
Sports nutrition is a constantly evolving field with hundreds of research papers published annually. For this reason, keeping up to date with the literature is often difficult. This paper is a five year update of the sports nutrition review article published as the lead paper to launch the JISSN in 2004 and presents a well-referenced overview of the current state of the science related to how to optimize training and athletic performance through nutrition. More specifically, this paper provides an overview of: 1.) The definitional category of ergogenic aids and dietary supplements; 2.) How dietary supplements are legally regulated; 3.) How to evaluate the scientific merit of nutritional supplements; 4.) General nutritional strategies to optimize performance and enhance recovery; and, 5.) An overview of our current understanding of the ergogenic value of nutrition and dietary supplementation in regards to weight gain, weight loss, and performance enhancement. Our hope is that ISSN members and individuals interested in sports nutrition find this review useful in their daily practice and consultation with their clients.  相似文献   
146.
This study examines the relationships between care felt and engagement in innovative behaviors at work. We posit that when an individual perceives that coworkers care for him or her (i.e., care felt), this cultivates psychological conditions such as safety, meaningfulness, and availability, which result in a higher level of motivation and by implication engagement in innovative behaviors at work. A sample of 218 employees took part in the assessment of the relationship between the psychological conditions linked to care felt (measured at Time 1) and motivation and engagement in innovative behaviors (measured at Time 2). The results of structural equation modeling (SEM) indicate that care felt is positively linked to psychological conditions. The latter is positively related directly and indirectly (through motivation) to engagement in innovative behaviors. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
147.
In the future, hydrogen-based stationary and portable fuel cell systems can help supply some or all of the power demanded with additional advantages of higher reliability, lower emissions, independence from the general grid, and cogeneration capability. In order to understand how to prepare the future for this technology, this paper describes a thorough investigation of past alternative stationary and portable power projects in order for an assessment of the opportunities for stationary and portable fuel cell markets, as well as interactions with transportation hydrogen systems. The lessons learned from the programs are used to establish best practices and recommendations for a hydrogen strategy that addresses opportunities for hydrogen in power generation systems, as well as to make recommendations for market transformation within the hydrogen fuel cell industry.  相似文献   
148.
This paper presents studies carried out on tin-doped indium sulfide films prepared using Chemical Spray Pyrolysis (CSP) technique. Effect of both in-situ and ex-situ doping were analyzed. Ex-situ doping was done by thermal diffusion, which was realized by annealing Sn/In2S3 bilayer films. In-situ doping was accomplished by introducing Sn into the spray solution by using SnCl4·5H2O. Interestingly, it was noted that by ex-situ doping, conductivity of the sample enhanced considerably without affecting any of the physical properties such as crystallinity or band gap. Analysis also showed that higher percentage of doping resulted in samples with low crystallinity and negative photosensitivity. In-situ doping resulted in amorphous films. In contrast to ex-situ doping, ‘in- situ doping’ resulted in widening of optical band gap through oxygen incorporation; also it gave highly photosensitive films.  相似文献   
149.
A transition model for internal flows which enables the prediction of the change of flow regime from turbulent through intermittent to laminar has been implemented by numerical simulation. This model had previously been demonstrated to be effective for the prediction of the breakdown of an initially laminar internal flow and its subsequent transitions to either intermittent or turbulent states. The model was employed here to study a flow which is decelerated by passing through a conical diffuser. The flow enters the diffuser with a fully developed turbulent velocity profile and exhibits transitions either in the diffuser or in a pipe situated downstream of the diffuser exit. The presence or absence of flow separation affected the onset of laminarization. Proof that laminarization actually occurred is provided by the values of the fully developed friction factors in the pipe downstream of the exit of the diffuser. These friction factors spanned the range from pure laminar flow through intermittent flow to fully turbulent flow. Comparisons were made with established benchmarks for each of these three flow regimes.  相似文献   
150.
Overnight tryptose broth cultures of three L monocytogenes strains were combined, centrifuged, suspended in 200 ml of tryptose phosphate broth, and heated at 56 degrees C for 20 min and at 64 degrees C for 2 min to obtain low-heat-injured (LHI) and high-heat-injured (HHI) cells, respectively, showing >99.6% injury. Flasks containing 200 ml of raw, low-heat-treated (56 degrees C for 20 min), high-heat-treated (64 degrees C for 2 min), pasteurized, and ultrahigh-temperature (UHT) milk were tempered to 31.1 degrees C and inoculated to contain 10(4) to 10(6) CFU/ml of LHI, HHI, or healthy L. monocytogenes cells and a commercial Lactococcus lactis subsp. lactis-Lactococcus lactis subsp. cremoris starter culture at levels of 0.5, 1.0, and 2.0%. Numbers of healthy and injured L. monocytogenes cells and starter organisms were determined using tryptose phosphate agar with or without 4.0% NaCl at selected intervals during 24 h of incubation at 31.1 degrees C. The presence of L. monocytogenes did not adversely affect the growth of the starter culture at any inoculation level. Overall, L. monocytogenes survived the 24-h fermentation period and grew to some extent. In starter-free controls. 76 to 81% of LHI cells and 59 to 69% of HHI cells were repaired after 8 h of incubation, with the lowest repair rates being observed for raw rather than heat-treated or pasteurized milk. Increased injury was observed for healthy L. monocytogenes cells at the 1.0 and 2.0% starter levels, with less injury seen for LHI and HHI cells. Raw and subpasteurized milk allowed less of a decrease in the percentage of injury and also showed higher numbers of injured cells than did pasteurized and UHT milks. These findings may have important implications for the survival of Listeria spp. in certain cheeses that can be prepared from raw or heat-treated milk.  相似文献   
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