科技进步五十年

通过回顾企业五十年的发展历程,阐述了科学技术在企业发展中发挥的重要作用.充分体现了科学技术是第一生产力.     

On the existence and synthesis of multifinger positive grips

We study the criteria under which an object can be gripped by a multifingered dexterous hand, assuming no static friction between the object and the fingers; such grips are calledpositive grips. We study three cases in detail: (i) the body is at equilibrium, (ii) the body is under some constant external force/torque, and (iii) the body is under a varying external force/torque. In each case we obtain tight bounds on the number of fingers needed to obtain grip.We also present efficient algorithms to synthesize such positive grips for bounded polyhedral/polygonal objects; the number of fingers employed in the grips synthesized by our algorithms match the above bounds. The algorithms run in time linear in the number of faces/sides.The paper may be of independent interest for its presentation of algorithms arising in the study of positive linear spaces.Work on this paper has been supported by Office of Naval Research Grant N00014-82-K.-0381, National Science Foundation Grant No. NSF-DCR-83-20085, and by grants from the Digital Equipment Corporation, and the IBM Corporation.     

羊二庄油田-断块明Ⅲ5层系开发效果分析

由于底水正韵律油藏的特殊性，在油藏开发后期，实施提高采收率的常规方法难以达到预期效果，油藏挖潜困难。在对羊二庄油田-断块Ⅲ5油藏地质特点分析的基础上。对开发历史上采用的各种治理手段，对断块油藏开发效果进行评价。并利用油藏数值模拟、精细油藏描述等技术，通过对油藏进行油水运移规律、底水油藏数值模拟等研究，得出油藏剩余油分布结论，进一步制定了符合油藏实际情况并在目前技术条件下可以实施的治理方法，目前已实施并取得成功。     

Crystallization and thermoelectric behavior of conductive-filler-filled poly(ε-caprolactone)/poly(vinyl butyral)/montmorillonite nanocomposites

Crystallization and thermoelectric properties of poly(ε-caprolactone) (PCL)/poly(vinyl butyral) (PVB)/montmorillonite (MMT) nanocomposites containing carbon black (CB) have been studied as a functions of a small amount of amorphous PVB content and a wide range of molecular weight of PVB. X-ray diffraction data of PCL/PVB/MMT nanocomposites indicates most of the swellable silicate layers are exfoliated and randomly dispersed into PCL/PVB system. The band spacings of PCL spherulites in PCL/PVB/MMT nanocomposites decrease with increasing PVB content, and this indicates that increasing the PVB content greatly shortens the period of lamellar twisting. The presence of 1 wt% MMT and higher molecular weight of PVB also shorten the period of PCL lamellar twisting. Nucleation and crystallization parameters, such as growth rate G and Avrami exponent n, can be determined by using POM and DSC isothermally crystallized at 41 °C. For samples with the same CB content, the intensity of positive temperature coefficient (PTC) (I_PTC, defined as the ratio of peak resistivity to resistivity at room temperature) of the nanocomposites was increased as the content and the molecular weight of PVB increases. The change of the PTC property related to the morphological difference (i.e. period of lamellar twisting) in the nanocomposites can be discussed.     

彩色多频同步显示器行激励级电路的倒推设计法（1）

行激励级电路的设计是完全为行输出级服务的,它实质上是行输出级电路设计的一个重要而不可分割的组成部分。因此行激励级电路的设计,自然采用了从显象管偏转线圈和行输出管到激励变压器和行激励级的倒推设计法。     

Differentiating anxiety and depression in older adults with generalized anxiety disorder.

To examine affect and cognition in differentiating anxiety and depression, 83 older participants with generalized anxiety disorder completed the Cognitive Checklist (CCL) and the Positive and Negative Affect Schedule (PANAS). A 3-factor solution was found for the PANAS: positive affect (PA), anxiety and anger (Negative Affect 1 [NA-1]), and guilt and shame (Negative Affect 2 [NA-2]). A 2-factor structure was noted for the CCL. Correlations with anxiety and depression measures suggested that the CCL Depression (CCL-D) subscale showed stronger correlations with depression, whereas the CCL Anxiety subscale did not uniquely correlate with anxiety. The NA-1 subscale correlated positively with measures of depression and anxiety, whereas the PA subscale showed negative correlations. Hierarchical regression suggested that the CCL-D subscale was a significant predictor of self-reported depression. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

浅谈做好螺丝湾水电站施工质量,工期,投资控制的几项措施

螺丝湾水电站作为云南省电力局（ 集团公司） 、迪庆州、省投资公司三方合资建设的电站，是迪庆藏族自治州自建国以来投资最大的一个建设项目，它的建成，开创了滇西北水电资源多方合资开发的先例，有其特殊的经济和政治意义。本文结合螺丝湾水电站建设的实际情况，论述了在市场经济条件下做好螺丝湾电站建设中“三控制”的几项措施     

Performance of in-call buffer/window allocation schemes for short intermittent file transfers over broadband packet networks

While static open loop rate controls may be adequate for handling continuous bit rate (CBR) traffic, relatively smooth data traffic, and relatively low speed bursty data traffic over broadband integrated networks, high speed bursty data sources need more dynamic controls. Burst level resource allocation is one such dynamic control. Potential benefits and other issues for burst level resource parameter negotiations for bursty data traffic over high speed wide area packet networks have been discussed earlier.^1–6 A detailed analysis of an adaptive buffer/window negotiation scheme for long file transfers using these concepts is presented in Reference 1. In this paper we discuss two burst level buffer/window negotiation schemes for short intermittent file transfers, focusing on the specific needs of such traffic streams. We develop closed network of queues models to reflect the behaviour of the proposed schemes. These models, while being simple, capture essential details of the control schemes. Under fairly general assumptions, the resulting network of queues is of product form and can be analysed using the mean value analysis. We use such an analysis to compare the proposed schemes and to determine appropriate sizes of trunk buffers to achieve the desired balance between bandwidth utilization and file transfer delay. The effects of other parameters on the performance of these schemes as well as on the buffer sizing rules are also discussed. Burst level (in-call) parameter negotiation may be carried out by the end system with the network elements or by an interface system (access controller) with the broadband network elements. We discuss implications of this location as well as the needed protocol features. Finally, the service discrimination capabilities desired at the trunk controllers in switching nodes are briefly discussed.     

On the solvability of the positive real lemma equations

In this paper, we consider the classical equations of the positive real lemma under the sole assumption that the state matrix A has unmixed spectrum: σ(A)∩σ(−A)=. Without any other system-theoretic assumption (observability, reachability, stability, etc.), we derive a necessary and sufficient condition for the solvability of the positive real lemma equations.     

关于缩短大电流开关二极管反向恢复时间的研究

通过长期的工作实践，阐述了适当条件下的金扩散对缩短反向恢复时间，提高二极管2CK28开关速度，满足了反向恢复时间，改善了二极管的反向特性。