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991.
Wentong Cai Jiannong Cao Wei Chen T. S. Dillon Minyi Guo Susumu Horiguchi Xiaohong Jiang Hiroaki Kobayashi Kin Wah Kwong Francis C. M. Lau Vinh Trong Le Bu-Sung Lee Son Hong Ngo Hiroyuki Takizawa Danny Tsang Cho-Li Wang Tianqi Wang Allan K. Y. Wong Richard S. L. Wu Percival Xavier Bin Xiao Laurence T. Yang Yanxiang He 《The Journal of supercomputing》2006,36(3):323-330
992.
This paper presents a unique novel design of the phase-shifted cascade high voltage inverter. The high voltage inverter utiJizes fewer power switches and supplies a balance load. The usage of phase shift transformer and phase shifting SPWM ensures that input and output harmonic wave content is low and output voltage change (du/dt) has a low rate, meeting all the requirements of the power authorities. The most outstanding feature is the energy saving with very fast cost recovery. 相似文献
993.
Agent-based modeling of supply chains for distributed scheduling 总被引:2,自引:0,他引:2
Lau J.S.K. Huang G.Q. Mak K.L. Liang L. 《IEEE transactions on systems, man, and cybernetics. Part A, Systems and humans : a publication of the IEEE Systems, Man, and Cybernetics Society》2006,36(5):847-861
This paper considers a supply chain that comprises multiple independent and autonomous enterprises (project managers) that seek and select various contractors to complete operations of their project. Both the project managers and contractors jointly determine the schedules of their operations while no single enterprise has complete information of other enterprises. The centralized scheduling approach that can usually obtain good global performance but must share nearly complete information that is difficult or even impractical due to the distributed nature of real-life supply chains. This paper proposes an agent-based supply chain model to support distributed scheduling. A modified contract-net protocol (MCNP) is proposed to enable more information sharing among the enterprises than conventional CNP. Experimental simulation studies are conducted to compare and contrast the performances of the centralized [centralized heuristic (CTR)], conventional CNP, and MNCP approaches. The results show that MCNP outperforms CNP and performs comparably with CTR when project complexity is high in terms of the total supply chain operating cost. Moreover, it is found that although CTR is better than MCNP in terms of global performance, MCNP yields good schedule stability when facing unexpected disturbances. 相似文献
994.
Chondrogenesis during embryonic skeletal development involves the condensation of mesenchymal cells followed by their differentiation into chondrocytes. We describe herein a previously unrecognized regulator of mammalian chondrogenesis encoded by a murine growth factor-inducible immediate-early gene, cyr61. The Cyr61 protein is a secreted, heparin-binding protein (379 amino acids with 38 conserved cysteines) that promotes cell adhesion, migration, and proliferation. The expression pattern of the cyr61 gene during embryogenesis is tissue specific and temporally regulated. Most notably, cyr61 is transiently expressed in mesenchymal cells of both mesodermal and neuroectodermal origins undergoing chondrogenesis, suggesting that Cyr61 may play a role in the development of the embryonic skeleton. In this communication, we demonstrate that the Cyr61 protein promotes chondrogenesis in micromass cultures of limb bud mesenchymal cells in vitro and is likely to play a similar role in vivo based on the following observations: (1) Cyr61 is present in the embryonic limb mesenchyme during chondrogenesis in vivo and in vitro; (2) purified recombinant Cyr61 protein added exogenously to micromass cultures promotes chondrogenesis as judged by precocious expression of type II collagen, increased [35S]sulfate incorporation, and larger Alcian blue-staining cartilage nodules; (3) Cyr61 enhances cell-cell aggregation, an initial step in chondrogenesis, and promotes chondrogenic differentiation in cultures plated at subthreshold cell densities that are otherwise unable to support differentiation; and (4) neutralization of the endogenous Cyr61 with specific antibodies inhibits chondrogenesis. Taken together, these results identify Cyr61 as a novel player in chondrogenesis that contributes to the development of the mammalian embryonic skeleton. 相似文献
995.
Evaluation of preoperative hepatic function in patients with hepatocellular carcinoma undergoing hepatectomy 总被引:1,自引:0,他引:1
BACKGROUND: Postoperative hepatic failure is the leading cause of hospital mortality following hepatectomy for hepatocellular carcinoma (HCC). This prospective study was performed to identify the best test for assessment of the adequacy of hepatic functional reserve in patients with HCC before hepatectomy. METHODS: Between April 1989 and June 1993, 127 patients with HCC underwent hepatectomy. Each patient was evaluated before operation with the indocyanine green (ICG) clearance test, the aminopyrine breath test and the amino acid clearance test. RESULTS: Fourteen patients (11 per cent) died after hepatectomy. ICG retention at 15 min showed significant differences between patients who survived or died. By discriminant analysis, the safety limit of ICG retention at 15 min for major hepatectomy was 14 per cent and the relative risk of hospital mortality was 3. CONCLUSION: The ICG clearance test, expressed as the percentage of ICG retained at 15 min, is the best discriminating preoperative test for evaluating hepatic functional reserve in patients with HCC before hepatectomy. 相似文献
996.
Cai Y. Cheng Z. Yang Z. Tang C. W. Lau K. M. Chen K. J. 《Electron Device Letters, IEEE》2007,28(5):328-331
This letter presents the high-temperature performance of AlGaN/GaN HEMT direct-coupled FET logic (DCFL) integrated circuits. At 375 degC, enhancement-mode (E-mode) AlGaN/GaN HEMTs which are used as drivers in DCFL circuits exhibit proper E-mode operation with a threshold voltage (VTH) of 0.24 V and a peak current density of 56 mA/mm. The monolithically integrated E/D-mode AlGaN/GaN HEMTs DCFL circuits deliver stable operations at 375 degC: An E/D-HEMT inverter with a drive/load ratio of 10 exhibits 0.1 V for logic-low noise margin (NML) and 0.3 V for logic-high-noise margin (NMH) at a supply voltage (VDD) of 3.0 V; a 17-stage ring oscillator exhibits a maximum oscillation frequency of 66 MHz, corresponding to a minimum propagation delay ( taupd) of 446 ps/stage at VDD of 3.0 V 相似文献
997.
A Low-Dropout Regulator for SoC With Q-Reduction 总被引:2,自引:0,他引:2
Sai Kit Lau Philip K. T. Mok Ka Nang Leung 《Solid-State Circuits, IEEE Journal of》2007,42(3):658-664
A low-dropout regulator for SoC, with an advanced Q-reduction circuit to minimize both the on-chip capacitance and the minimum output-current requirement down to 100 muA, is introduced in this paper. The idea has been implemented in a standard 0.35-mum CMOS technology (VTHN ap 0.55 V and |VTHP| ap 0.75 V). The required on-chip capacitance is reduced to 6 pF, comparing to 25 pF for the case without Q-reduction circuit. From the experimental results, the proposed regulator-circuit implementation enables voltage regulation down to a 1.2-V supply voltage, and a dropout voltage of 200 mV at 100-mA maximum output current 相似文献
998.
Robust joint interference detection and decoding for OFDM-based cognitive radio systems with unknown interference 总被引:1,自引:0,他引:1
Li T. Mow W.H. Lau V.K.N. Siu M. Cheng R.S. Murch R.D. 《Selected Areas in Communications, IEEE Journal on》2007,25(3):566-575
Cognitive radio technology facilitates spectrum reuse and alleviates spectrum crunch. One fundamental problem in cognitive radio is to avoid the interference caused by other communication systems sharing the same frequency band. However, spectrum sensing cannot guarantee accurate detection of the interference in many practical situations. Hence, it is crucial to design robust receivers to combat the in-band interference. In this paper, we first present a simple pilot aided interference detection method. To combat the residual interference that cannot be detected by the interference detector, we further propose a robust joint interference detection and decoding scheme. By exploiting the code structure in interference detection, the proposed scheme can successfully detect most of the interfered symbols without requiring the knowledge of the interference distribution. Our simulation results show that, even without any prior knowledge of the interference distribution, the proposed joint interference detection and decoding scheme is able to achieve a performance close to that of the maximum likelihood decoder with the full knowledge of the interference distribution 相似文献
999.
Scalability of Web-based electronic commerce systems 总被引:1,自引:0,他引:1
Bochmann G.V. Wong J.W. Evans D. Lau T.C. Bourne D. Kerherve B. Salem M.-V.M. Haiwei Ye 《Communications Magazine, IEEE》2003,41(7):110-115
In a Web-based electronic commerce system, users browse product information offered by an online store and submit requests to purchase selected items. From the user's perspective, response time is a factor that could impact the acceptability of electronic commerce. This article is concerned with system architectures for online stores. Emphasis is placed on techniques to improve a system's capacity to support more users without suffering a noticeable degradation in response time performance. Such techniques have been investigated as part of a Canadian Institute for Telecommunications Research major project entitled Enabling Technology for Electronic Commerce Applications, developed in close collaboration with the IBM/sup /spl reg// Centre for Advanced Studies. The basic architecture of a Web-based electronic commerce system is first described along with the types of data that need to be managed. Next, an overview of existing techniques for improving system capacity is presented. Finally, highlights of research results obtained as part of the CITR electronic commerce major project are discussed. 相似文献
1000.
Synthesis of sustainable integrated biorefinery via reaction pathway synthesis: Economic,incremental enviromental burden and energy assessment with multiobjective optimization
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Viknesh Andiappan Andy S. Y. Ko Veronica W. S. Lau Lik Yin Ng Rex T. L. Ng Nishanth G. Chemmangattuvalappil Denny K. S. Ng 《American Institute of Chemical Engineers》2015,61(1):132-146
With the increasing attention toward sustainable development, biomass has been identified as one of the most promising sources of renewable energy. To convert biomass into value‐added products and energy, an integrated processing facility, known as an integrated biorefinery is needed. To date, various biomass conversion systems such as gasification, pyrolysis, anaerobic digestion and fermentation are well established. Due to a large number of technologies available, systematic synthesis of a sustainable integrated biorefinery which simultaneously considers economic performance, environmental impact, and energy requirement is a challenging task. To address this issue, multiobjective optimization approaches are used in this work to synthesize a sustainable integrated biorefinery. In addition, a novel approach (incremental environmental burden) to assess the environmental impact for an integrated biorefinery is presented. To illustrate the proposed approach, a palm‐based biomass case study is solved. © 2014 American Institute of Chemical Engineers AIChE J, 61: 132–146, 2015 相似文献