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81.
BillHoward 《个人电脑》2003,9(6):149-149
有谁相信Intel和MIcrosoft所说的一切吗7我也不相信。所以我对过去两周PC Magazine实验室的结果感到吃惊:配备新型1.6GHz Intel Pentium M CPU的centnno系统堪与配备3.06GHz台式机芯片的笔记本媲美,Centrino系统的电池寿命几乎是近期的高端笔记本的两倍。Centrino笔记本几乎具备我们所希望的以及Intel所声称的一切优点。  相似文献   
82.
Bill Howard 《个人电脑》2003,9(2):121-121
现在名牌笔记本电脑也卖到1000美元以下了,你也该想想你的下一台PC是否应该是笔记本  相似文献   
83.
This paper introduces the ideas behind BPML, the business process modelling language published by BPMI. BPML provides a process-centric (as opposed to a datacentric) metalanguage and execution model for business systems. It is underpinned by a strong mathematical foundation, the pi-calculus. The current paper is derived from supplementary appendices to a book which describes a ‘third wave’ approach to business process management [Business Process Management: The Third Wave, 2003]. The aim is to model business processes directly in an executable form, so that the mobility and mutability inherent in business behaviour is reflected and supported in the corresponding IT systems, erasing the present IT-business divide.  相似文献   
84.
This paper explores a formalism for describing a wide class of multimedia document constraints, based on an interval temporal logic. We describe the requirements that arise from the multimedia documents application area, and we illustrate these requirements using several examples. Then we present the temporal logic formalism that we use. This logic extends existing interval temporal logic with a number of new features: actions, framing of actions, past operators, a projection-like operator called filter and a new handling of interval length. The notation is applied to the specification of the examples, and in particular a set of logical manipulations, providing feedback to an author, is presented. A model theory, logic and satisfaction relation are defined for the notation.  相似文献   
85.
The performance of conjugate gradient (CG) algorithms for the solution of the system of linear equations that results from the finite-differencing of the neutron diffusion equation was analyzed on SIMD, MIMD, and mixed-mode parallel machines. A block preconditioner based on the incomplete Cholesky factorization was used to accelerate the conjugate gradient search. The issues involved in mapping both the unpreconditioned and preconditioned conjugate gradient algorithms onto the mixed-mode PASM prototype, the SIMD MasPar MP-1, and the MIMD Intel Paragon XP/S are discussed. On PASM , the mixed-mode implementation outperformed either SIMD or MIMD alone. Theoretical performance predictions were analyzed and compared with the experimental results on the MasPar MP-1 and the Paragon XP/S. Other issues addressed include the impact on execution time of the number of processors used, the effect of the interprocessor communication network on performance, and the relationship of the number of processors to the quality of the preconditioning. Applications studies such as this are necessary in the development of software tools for mapping algorithms onto either a single parallel machine or a heterogeneous suite of parallel machines.  相似文献   
86.
This article presents a novel experimental technique to infer the coupled effects of friction and heat transfer during the hot rolling of steels. The technique, termed the “cut-groove” method, relates the behavior of the deforming grooves cut on the strip surface to the local effects of friction and heat transfer. Validation of the experimentally observed groove shapes involved developing two-dimensional (2-D) and three-dimensional (3-D) finite-element (FE) models that employed a probabilistic distribution diagram (PDD). The PDD framework modeled the roll-strip interface and accounted for the variations in the oxide scale as distinct states that affect both friction and heat transfer. The numerically predicted groove openings are in good agreement with the experimentally observed groove shapes, particularly for the 2-D case. For the 3-D model, deviations are observed at regions close to the strip edges that are affected by nonplanar strain arising from spread during laboratory rolling. S. DAS, formerly Student, Department of Engineering Materials, and later Research Associate, Institute of Microstructural and Mechanical Process Engineering, The University of Sheffield (IMMPETUS), Sheffield, SI 3JD, United Kingdom  相似文献   
87.
Reward,persuasion, and the Sokal Hoax: A study in citation identities   总被引:1,自引:0,他引:1  
White  Howard D. 《Scientometrics》2004,60(1):93-120
A citation identity is a list of an author's citees ranked by how frequently that author has cited them in publications covered by the Institute for Scientific Information. The same Dialog software that creates identities can simultaneously show the overall citation counts of citees, which indicate their reputations. Using identities for 28 authors in several disciplines of science and scholarship, I show that the reputational counts of their citees always have an approximately log-normal distribution: citations to very famous names are roughly balanced by citations to obscure ones, and most citations go to authors of middling reputation. These results undercut claims by constructivists that the main function of citation is to marshal “big-name” support for arguments at the expense of crediting lesser-known figures. The results are better explained by Robert K. Merton's norm of universalism, which holds that citers are rewarding use of relevant intellectual property, than by the constructivists' particularism, which holds that citers are trying to persuade through manipulative rhetoric. A universalistic citation pattern appears even in Alan Sokal's famous hoax article, where some of his citing was deliberately particularistic. In fact, Sokal's basic adherence to universalism probably helped his hoax succeed, which suggests the strength of the Mertonian norm. In specimen cases, the constructivists themselves are shown as conforming to it. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
88.
Acquisition of odor-guided or visually-guided delayed win-shift behavior was evaluated in rats after lidocaine-induced inactivation within the agranular insular area of the prefrontal cortex (PFC) or the prelimbic area of the PFC. Additional sites and tasks were used to control for neuroanatomical and behavioral specificity of lidocaine inactivation of the agranular insular and prelimbic areas. Results showed that acquisition of the odor-guided delayed win-shift task was dependent on the agranular insular area, whereas acquisition of the visually-guided version was dependent on the prelimbic area. This dissociation suggests that the stimulus modality used is critical for revealing working memory functions of different PFC subregions. The described methods provide a complementary means to study working memory in PFC subregions using a radial-arm maze. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
89.
Foodborne illness caused by Salmonella spp. is a worldwide problem. In the United States Salmonella Enteritidis is the second most commonly isolated serotype from human illness, and is known to be strongly associated with shell eggs and egg containing products. Eggs can become contaminated internally either by penetration through the shell or directly during formation in the reproductive tract. This review begins with a brief account of the physiology of egg production and the various physical and chemical barriers the egg possesses to prevent bacterial contamination. Factors involved in vertical and horizontal transmission of S. Enteritidis are examined, as well as the role of forced molt in colonization of the hen. Pre- and post-harvest mitigation strategies are also discussed.  相似文献   
90.
Uniform spherical beads were used to explore the scaling behavior of a granular system near its critical angle of repose on a conical 3D bead pile. We found two tuning parameters that could take the system to a critical point. The existence of those tuning parameters violates the fundamental assumption of self-organized criticality, which proposed that complex dynamical systems self-organize to a critical point without need for tuning. Our avalanche size distributions were well described by a simple power-law, as is characteristic of a critical point, with the power τ = 1.5 when dropping beads slowly onto the apex of a bead pile from a small height. However, we could also move the system from the critical point using either of two tuning parameters: the height from which the beads fell onto the top of the pile or the region over which the beads struck the pile. As the drop height increased, the system did not reach the critical point yet the resulting distributions were independent of the bead mass, coefficient of friction, or coefficient of restitution. All our apex-dropping distributions for any type of bead (glass, stainless steel, zirconium) showed universality by scaling onto a common curve with τ = 1.5 and σ =?1.0, where 1/σ is the power of the tuning parameter. From independent calculations using the moments of the distribution, we find values for τ = 1.6 ± 0.1 and σ =?0.91 ± 0.15. When beads were dropped across the surface of the pile instead of solely on the apex, then the system also moved from the critical point and again the avalanche size distributions fell on a common curve when scaled similarly using the same values of τ and σ. We also observed that an hcp structure on the base of the pile caused an emergent structure in the pile that had six faces with some fcc or hcp structure; this structure did not affect the distribution of avalanche sizes.  相似文献   
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