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91.
2004年,我们考虑将全球报道作为每年的一项工作,它将使我们能充分利用我们在全球的编辑资源,并以我们的文章为全球读者服务。读者似乎很欣赏创刊版和2005版,因此我们现在提供第三期年度报道。全世界的工程师都面临着按照国际标准和规定来做设计,其工作的全球市场潜力等全球性问题。我们相信:您将会发现《全球报道3》在这两方面都会给予您启发。今年,我们的全球报道侧重于各种围绕四个设计领域的全球性问题。模拟设计,电源系统设计,基于微处理器的设计、芯片设计。本期全球报道都包含一篇针对上述每个领域的基础文章。此外,每个部分都包含若干篇附文,用其它学科、产品和应用的相关信息来实现全面覆盖,例如测试、可编程逻辑和无线通信。  相似文献   
92.
Quantifying evapotranspiration (ET) from agricultural fields is important for field water management, water resources planning, and water regulation. Traditionally, ET from agricultural fields has been estimated by multiplying the weather-based reference ET by crop coefficients (Kc) determined according to the crop type and the crop growth stage. Recent development of satellite remote sensing ET models has enabled us to estimate ET and Kc for large populations of fields. This study evaluated the distribution of Kc over space and time for a large number of individual fields by crop type using ET maps created by a satellite based energy balance (EB) model. Variation of Kc curves was found to be substantially larger than that for the normalized difference vegetation index because of the impacts of random wetting events on Kc, especially during initial and development growth stages. Two traditional Kc curves that are widely used in Idaho for crop management and water rights regulation were compared against the satellite-derived Kc curves. Simple adjustment of the traditional Kc curves by shifting dates for emergence, effective full cover, and termination enabled the traditional curves to better fit Kc curves as determined by the EB model. Applicability of the presented techniques in humid regions having higher chances of cloudy dates was discussed.  相似文献   
93.
The amnesic shellfish poisoning mystery   总被引:6,自引:0,他引:6  
  相似文献   
94.
This volume contains the Proceedings of the REFINE 2002 workshop. The Workshop was held in Copenhagen, Denmark on July 20 and 21, 2002, as a satellite event to FLoC'02 as an FME-affiliated workshop.Refinement is one of the cornerstones of a formal approach to software engineering. Refinement is the process of developing a more detailed design or implementation from an abstract specification through a sequence of mathematically-based steps that maintain correctness with respect to the original specification.The aim of this BCS FACS refinement workshop was to bring together people who are interested in the development of more concrete designs or executable programs from abstract specifications using formal notations, tool support for formal software development, and practical experience with formal refinement methodologies.The purpose of the workshop was to provide a forum for discussion of common ground and key differences. Topics of interest included:
• Simulation techniques
• Foundations and semantics
• Case studies (specification and verification)
• Compositional and modular reasoning
• Object-orientation
• Time
• Specification notations
• Programming models
• Verification and tool support
The workshop continued a long tradition of refinement workshops run under the auspices of the British Computer Society (BCS) FACS special interest group. Running since 1988, previous refinement workshops have been held at Cambridge, London, Bath etc.In 1998 the BCS refinement workshop was combined with the Australasian Refinement Workshop to form the International Refinement Workshop, hosted at alongside Formal Methods Pacific 1998 at The Australian National University.The papers in this volume were reviewed by a small program committee consisting of
John Derrick<
jd1@ukc.ac.uk
, University of Kent, UK.
Eerke Boiten<
eab2@ukc.ac.uk
, University of Kent, UK.
Jim Woodcock<
jcpw@ukc.ac.uk
, University of Kent, UK.
Joakim von Wright<
jockum.wright@abo.fi
, Åbo Akademi University, Finland
Additional information about the Workshop can be found at: http://www.cs.ukc.ac.uk/people/staff/eab2/refine/floc.htmlThis volume will be published as volume 70 issue 3 in the series Electronic Notes in Theoretical Computer Science (ENTCS). This series is published electronically through the facilities of Elsevier Science B.V. and its auspices. The volumes in the ENTCS series can be accessed at the URLhttp://www.elsevier.nl/locate/entcsA printed version of the current volume was distributed to the participants at the workshop in Denmark.We are very grateful to the following persons, whose help has been crucial for the success of REFINE 2002: Lars-Henrik Eriksson and Peter Lindsay of FME for their help with the organization of the Workshop as satellite event of FLoC'02 and an FME affiliated workshop; Mike Mislove, one of the Managing Editors of the ENTCS series, for his assistance with the use of the ENTCS style files. Thanks are also due to the Computing Laboratory of the University of Kent, which supplied financial support to cover the printing costs.July 24, 2002John Derrick  相似文献   
95.
This paper reports on the development of an MPI/OpenCL implementation of LU, an application-level benchmark from the NAS Parallel Benchmark Suite. An account of the design decisions addressed during the development of this code is presented, demonstrating the importance of memory arrangement and work-item/work-group distribution strategies when applications are deployed on different device types. The resulting platform-agnostic, single source application is benchmarked on a number of different architectures, and is shown to be 1.3–1.5× slower than native FORTRAN 77 or CUDA implementations on a single node and 1.3–3.1× slower on multiple nodes. We also explore the potential performance gains of OpenCL’s device fissioning capability, demonstrating up to a 3× speed-up over our original OpenCL implementation.  相似文献   
96.
A new laser transfer process is reported which allows damage-free transfer of ferroelectric thin films from a growth substrate directly to a target substrate. The thin film ferroelectric material is deposited on a fused silica growth substrate with a sacrificial release layer of ITO (indium tin oxide). Regions of the film that are to be transferred are then selectively metallised, and bonded to the target substrate. Separation from the growth substrate is achieved by laser ablation of the ITO release layer by a single pulse from a KrF excimer laser, with the laser light being incident through the growth substrate. The residual ITO on the transferred ferroelectric layer is electrically conducting, and may be suitable for incorporation into the final device, depending on the application. The new process has been demonstrated for 500 nm-thick layers of sol-gel PZT which were thermosonically bonded to a silicon target substrate prior to laser release. The transferred films show ferroelectric behaviour and have a slightly reduced permittivity compared to the as-deposited material.  相似文献   
97.
98.
Norman Garmezy, a pioneer in research on risk and resilience, died in Nashville, Tennessee, on November 21, 2009, at the age of 91. He was a legendary mentor as well as an eminent scientist in clinical psychology. Norm was born on June 18, 1918, in New York City and grew up in the Bronx in a Jewish neighborhood where educational attainment was highly valued. The scientific study of resilience as conceived by Norman Garmezy, his peers, and students has transformed the science and practice of multiple disciplines, from the molecular level to the global ecosystem, infusing a strength-based and recovery-oriented approach into psychology, education, social work, and psychiatry. Current research on resilience ranges from studies of plasticity in brain development to effective planning for resilience in the context of disaster. Norm’s influential ideas and research earned him international acclaim and many honors for lifetime achievements in science. Throughout his career, Norm held many leadership roles. Throughout his life, Norm spoke with great love about his wife of 63 years, Edie Garmezy (who died just months before him in 2009), and their children. In addition to his work and his family, Norm had three abiding passions—theater, movies, and politics. During the last two decades of his life, Norm and those who loved him endured his long decline from Alzheimer’s, which slowly stole his brilliant mind and hilarious sense of humor. Nonetheless, the incredible spirit and humanity of this giant scholar continued to shine through this terrible disease. To the end of his life, Norm’s face would light up with a smile as he greeted the people he loved, and he would often exclaim, “Wonderful!” Norman Garmezy was a remarkable person and scholar who left an extraordinary legacy of love and work to inspire future generations in their efforts to understand and promote the human capacity for competence and resilience. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
99.
We have tested the effectiveness of punch-through protection (PTP) structures on n-on-p AC-coupled Silicon strip detectors using pulses from an 1064 nm IR laser, which simulate beam accidents. The voltages on the strips are measured as a function of the bias voltage and compared with the results of DC I-V measurements, which are commonly used to characterize the PTP structures. We find that the PTP structures are only effective at very large currents (several mA), and clamp the strips to much larger voltages than assumed from the DC measurements. We also find that the finite resistance of the strip implant compromises the effectiveness of the PTP structures.  相似文献   
100.
A finite element (FE) analysis has been undertaken to evaluate the stress and strain distribution associated with a single corrosion pit in a cylindrical steel specimen stressed remotely in tension. A key observation was the localisation of plastic strain to the pit walls (just below the surface of the specimen). Simulation of a growing pit in a static stress field indicated corresponding plastic strain rates that were commensurate with values associated with stress corrosion cracking. This observation introduces a wholly new concept in understanding of the evolution of stress corrosion cracks from pits and correlates with recent X-ray tomography measurements.  相似文献   
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