图书馆计算机应用模式选择

目前我国图书馆的计算机应用模式主要有6种,其中微机多用户、微机局域网和小型机系统模式,在我国高校图书馆具有较大的实际可行性。图书馆可以根据本馆的藏书量和业务开展情况,选择适宜的应用模式。文章还在图书馆规模划分的基础上,探讨了不同规模图书馆的模式选择问题,并提出了倾向性意见。     

北京大学图书馆隆重庆祝建馆100周年

2002年，北京大学图书馆欣逢建馆一百周年。北京大学图书馆在盛世金鹰等企业的赞助下，经过精心的策划准备，举行了一系列庆祝活动。10月23日上午，庆祝北京大学图书馆建馆一百周年大会在北京大学英杰交流中心举行。德高望重的北大名师季羡林、侯仁之先生，教育部副部长袁贵仁，文化部副部长赵维绥，新闻出版署副署长柳斌杰，国家图书馆馆长任继愈，国家自然科学基金委主任陈佳洱院士，北京大学党委书记闵维方、副书记赵存生，北大图书馆馆长戴龙基，来自海内外的百余名著名大学图书馆馆长，北京大学各院系领导以及图书馆全体馆员共500余人…     

Estimating the time-dependent reliability of aging structures in the presence of incomplete deterioration information

The performance of an aging structure is commonly evaluated under the framework of reliability analysis, where the uncertainties associated with the structural resistance and loads should be taken into account. In practical engineering, the probability distribution of resistance deterioration is often inaccessible due to the limits of available data, although the statistical parameters such as mean value and standard deviation can be obtained by fitting or empirical judgments. As a result, an error of structural reliability may be introduced when an arbitrary probabilistic distribution is assumed for the resistance deterioration. With this regard, in this paper, the amount of reliability error posed by different choices of deterioration distribution is investigated, and a novel approach is proposed to evaluate the averaged structural reliability under incomplete deterioration information, which does not rely on the probabilistic weight of the candidate deterioration models. The reliability for an illustrative structure is computed parametrically for varying probabilistic models of deterioration and different resistance conditions, through which the reliability associated with different deterioration models is compared, and the application of the proposed method is illustrated.     

Squeal noise in hydraulic poppet valves

The poppet valve is a fundamental component in fluid power systems. Under particular conditions, annoying “squeal” noises may be generated in hydraulic poppet valves. In the present study, the frequency spectrum of the squeal noise is obtained by analyzing the sampling data from the accelerometer mounted on the valve body. It is found that the flow velocity, pressure, and structural parameters have crucial effects on the properties of squeal noise, especially frequency. Larger valve chamber volume or lower backpressure leads to lower fundamental frequency of the squeal noise. An explanation for the squeal noise, as a result of Helmholtz resonance, is suggested and proved by experimental results.     

论我国高校人力资源的柔性管理

文章认为柔性管理适应新知识时代高校人力资源的要求,在分析柔性管理的特点及与刚性管理关系的基础上,对如何在我国高等院校实施人力资源柔性管理进行了探讨。     

亚磷酸二甲酯的合成

本文以三氯化磷和甲醇为原料,用苯作溶剂合成亚磷酸二甲酯,确定了最佳反应条件,获得较满意的结果。     

中小学生"创造性问题提出能力"及其培养

“创造性问题提出能力”是根据一定的目的,运用已有情境或经验,在独特地、新颖地、具有价值地(或恰当地)创造新问题并表达新发现问题的过程中,表现出来的智能品质或能力。学校教育、家庭环境、自身因素影响中小学生创造性问题提出能力的发展;优化发展环境、激发学习动机、教给提问方法、训练思维品质、及时正确反馈,是培养中小学生创造性问题提出能力的有效途径。     

研究性教学模式在教学中的应用

为了适应新课程标准的要求及素质教育改革的新形势,我在所从事的vfp教学中引入了国家提倡的实践性学习教学模式,目的是改变以“接受性学习”为主的传统的课堂教学,在接受性学习与研究性学习之间找到恰当的平衡点,从而培养学生的创新精神和实践能力。     

Co-design for an SoC embedded network controller

INTRODUCTION With the development of Ethernet systems and the growing capacity of modern silicon technology, embedded communication networks are playing an increasingly important role in embedded and safety critical systems. Advances in VLSI technology have also pushed integration to the point where it is now possible to design and implement a microprocessor and network controller on a single chip, known as System-on-Chip (SoC). In a network of embedded systems, each system can communi…     

论自然人都有民事责任能力

传统观点认为只有部分自然人有民事责任能力,和民事权利能力相冲突。自然人有无民事责任能力是考虑自然人有无行为能力的前提,有无行为能力是考虑自然人在过错责任原则下是否需要承担责任的前提。无责任能力的自然人基于衡平事由承担结果责任说明无责任能力的自然人是有民事责任能力的。传统观点中所界定的“民事责任能力”其实是自然人以自己的财产承担自己责任的条件,在自然人有民事责任能力的前提下才讨论传统观点中所界定的“民事责任能力”,是比民事责任能力低一个层次的问题。