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671.
Banerjee S. Hamada T. Chau P.M. Fellman R.D. 《Signal Processing, IEEE Transactions on》1995,43(6):1468-1484
Presents a technique for pipelining heterogeneous multiprocessor systems, macro pipelining based scheduling. The problem can be identified as a combination of optimal task/processor assignment to pipeline stages as well as a scheduling problem. The authors propose a new technique based on iterative applications of partitioning and scheduling schemes whereby the number of pipeline stages are identified and the scheduling problem is solved. The pipeline cycle is optimized in two steps. The first step finds a global coarse solution using the ratio cut partitioning technique. This is subsequently improved by the iterative architecture driven partitioning and the repartitioning and time axis relabeling techniques of the second step. The authors have considered a linear interprocessor communication cost model in scheduling. The proposed technique is applied to several examples. They find that for these examples, the proposed macro pipelining based scheduling can improve the throughput rate several times that of the conventional homogeneous multiprocessor scheduling algorithms 相似文献
672.
Melioidosis is the name given to all diseases caused by the bacterium Pseudomonas pseudomallei. Melioidosis is a tropical disease and prevails in parts of Southeast Asia, northern Australia, and Central and South America. However, in recent years, cases of melioidosis have been reported in the United States and other areas. The organism can infect any organ system, although the lung is the most common organ affected. Pulmonary melioidosis presents either as an acute fulminant pneumonia or as an indolent cavitary disease. In northeastern Thailand, the incidence of P pseudomallei infection is extremely high with significant mortality. One of the key problems with treating melioidosis is its recalcitrance to therapy and high relapse rate. In addition, this Gram-negative rod is resistant to aminoglycosides. In nonendemic regions, patients with melioidosis more typically present with reactivation disease occurring months to years after initial exposure to the organism. The pulmonary disease is mainly in the apices and resembles tuberculosis. With the increasing mobility of people throughout the world and the influx of immigrants from endemic to nonendemic areas, it is important that clinicians be aware of this disease. This article will review the epidemiology, clinical presentations, diagnosis, and treatment of pulmonary melioidosis. 相似文献
673.
A procedure for the analysis of 3-trifluoromethyl-4-nitrophenol (TFM) in natural waters is described. The lampricide is extracted from acidified water samples on the macroreticular resin XAD-7 and eluted from the column with ethyl ether. The ether extract is dried, concentrated, and partitioned with potassium carbonate. TFM is acetylated in the aqueous alkaline solution and the acetate derivative is extracted into benzene for analysis by electron capture gas-liquid chromatography. Recoveries of TFM from natural waters exceeded 90% and as little as 0.01 mug TFM can be quantitated in a 1 L sample. 相似文献
674.
Ng G.-I. Pavlidis D. Jaffe M. Singh J. Chau H.-F. 《Electron Devices, IEEE Transactions on》1989,36(10):2249-2259
Strained In0.52Al0.48 As/InxGa 1-xAs (x >0.53) HEMTs (high electron mobility transistors) are studied theoretically and experimentally. A device design procedure is reported that is based on band structure and charge control self-consistent calculations. It predicts the sheet carrier density and electron confinement as a function of doping and thickness of layers. The DC performance at 300 K is presented. Wafer statistics demonstrate improvement of device characteristics with excess indium in the channel (g¯m, intr=500 and 700 mS/mm for x=0.60 and 0.65). Microwave characterization shows the f T improvement (f T=40 and 45 GHz for x =0.60 and 0.65, respectively) and the R ds limitations of the 1-μm-long-gate HEMTs 相似文献
675.
Kin W. Chau 《Journal of Adhesion Science and Technology》2013,27(14):1535-1547
A tacky elastomer, the pressure-sensitive adhesive spontaneously bonds with a solid on contact to form a load-bearing pressure-sensitive adhesive joint (PSAJ) that makes many manufactured goods. While the property called the tack of the PSAJ, measured by the green strength of the joint at low applied stress, is vigilantly monitored for quality assurance, it harbors considerable indefinitude because it increases with applied stress and age to span a continuous spectrum that no finite number of discrete empirical readings can fully cover. Assuming the joint strength to be proportional to adhesive/substrate contact area on the atomic level, and treating the contact process as atomic-scale creep, this work determines from first principles the measured tack of a given PSAJ as a function of applied stress and age. The quantitative structure of the function and its implications are explored. The result is tested with published empirical data and used as a basis for mapping the tack spectrum from discrete readings. It brings settlement of long-standing issues such as ranking PSAJs by their non-corresponding tack readings, explaining the disconcertingly high noise : signal ratios plaguing tack data, buffering the uncertainty and extending the domain of tack measurement. It also shows that the tack and the mature joint strength constitute one smooth continuous spectrum. 相似文献
676.
A two‐phase approach for single machine scheduling problems: Minimizing the total absolute deviation
Abstract This paper presents a heuristic for solving a single machine scheduling problem with the objective of minimizing the total absolute deviation. The job to be scheduled on the machine has a processing time, pi , and a preferred due date, di . The total absolute deviation is defined as the sum of the earliness or tardiness of each job on a schedule 5. This problem is proved to be NP‐complete by Garey et al. [8]. As a result, we developed a two‐phase procedure to provide a near‐optimal solution to this problem. The two‐phase procedure includes the following steps: First, a greedy heuristic is applied to the set of jobs, N, to generate a “good” initial sequence. According to this initial sequence, we run Garey's local optimization algorithm to provide an initial schedule. Then, a pairwise switching algorithm is adopted to further reduce the total deviation of the schedule. The effectiveness of the two‐phase procedure is empirically evaluated and has been found to indicate that the solutions obtained from this heuristic procedure are often better than other heuristic approaches. 相似文献
677.
Microprocessor-controlled prostheses facilitate a more natural and efficient gait for individuals with above-knee amputations by continually adjusting the level of swing-phase damping. One caveat associated with these technologies is that the user must charge the onboard batteries on a daily basis. It is, therefore, the aim of this study to examine the feasibility of using an electromechanical system to provide prosthetic swing-phase damping and, concomitantly, the function of converting physiological energy that is normally dissipated during the swing phase, to electrical energy. Gait data from a single subject and data from a kinematic simulator were used to develop an empirical model. The findings in this study indicate that an electromagnetic system has appropriate characteristics for use in swing-phase control and also has the potential to recover energy under particular conditions. 相似文献
678.
Long D. Nguyen Long Le-Hoai Dai Q. Tran Chau N. Dang Chau V. Nguyen 《Construction Management & Economics》2019,37(7):384-399
Project complexity is a contributing factor to project performance. Understanding how project complexity interacts with management actions and project performance is imperative. This study fills this knowledge gap by empirically exploring the relationship between construction project complexity and project performance and their interaction with resource allocation. Empirical data were collected from 79 transportation projects. Due to its capability to build several regression models by adding independent variables to previous models, moderated hierarchical regression analyses were conducted to identify the underlying effect of resource allocation on the project complexity and performance relationship. The results show that: (i) project complexity was significantly correlated with schedule growth (positive correlation) but not significantly correlated with cost growth; (ii) resource allocation was significantly correlated with schedule growth (negative correlation) but not with cost growth; and (iii) resource allocation had a buffering effect where increasing resource allocation significantly decreases the effect of project complexity on schedule growth. The findings from this study contribute to the extant literature on construction project complexity by empirically showing that the impact of project complexity on schedule performance interacts with the level of resource allocation. This understanding of the role of resource allocation may help construction managers and engineers to better administer and manage their complex transportation projects. The findings also imply that organizations should appropriately evaluate project complexity to allocate necessary resources to achieve project success. 相似文献
679.
The disposal of plastic foam, mostly composed of polystyrene, poses significant environmental challenges due to its high popularity, slow degradation, and low cost. To address this problem, recycling polystyrene foam waste (PF) has emerged as a promising solution to reduce plastic pollution. This paper presents a novel approach to mass-produce highly ordered, porous honeycomb-patterned film (hc-film) using wasted PF as the raw material. The hc-film is produced using an improved phase separation (IPS) method that utilizes methanol as a suitable pore inducer and template droplet stabilizer. Methanol provides the hc-film with customizable features such as pore ordering, size, and separation. The freestanding hc-film, achieved by adopting a water-soluble polystyrene sulfonate as a scarified layer, can be transferred and utilized as a flexible mold to pattern various solid substrates with complicated surface morphologies using the pre-impregnated technique. This study demonstrates the potential of this cost-effective and efficient approach for various applications, such as super/anti-wetting surfaces, microelectronics, optical devices, sensors, and nanogenerators. 相似文献
680.
Joseph Lik Hang Chau Chun-Yen ChenMin-Chieh Yang Kwang-Lung LinShunichi Sato Takahiro NakamuraChih-Chao Yang Chung-Wei Cheng 《Materials Letters》2011,65(4):804-807
Bimetallic Pt-Au nanoparticles were successfully synthesized by irradiating the metal precursor solution with high intensity femtosecond laser. The intense optical field created by femtosecond laser pulse induced the production of highly charged ions and molecules due to the optical decomposition of metal precursor molecules. Further collisions with molecules result in subsequent growth of the nuclei and codeposition of Pt and Au atoms on the nuclei to form the larger ones. The method is a simple, easy-to-control and environmentally benign process. The average size and morphology of bimetallic nanoparticles were examined by transmission electron microscope. The compositional distributions of Pt and Au of individual Pt-Au nanoparticles were examined by X-ray energy dispersive spectroscopy (EDS). 相似文献