Use of Dewey Decimal Classification by Academic Libraries in the United States

Abstract

Nearly 25 years have elapsed since the last comprehensive measure of the percentage of academic libraries that employ the Dewey and Library of Congress systems of classification. To provide updated statistics, the researchers surveyed all 3793 academic libraries via their online catalogs. The findings indicate that the use of Dewey has declined over the past four decades. Teachers’ Colleges and Community Colleges in particular have higher rates of Dewey use than large research or professional universities. This information may help support academic library reclassification decisions.     

Classifying the Imaginary: An Expansion of Library of Congress’ Subclass G9930 for Local Use

Abstract

Class G provides granular classification for most cartographic materials through a well-established and expanded Cuttering system, maps of imaginary places are classified under G9930 which has no formal expansion. With the creation of a collection of imaginary maps at the Texas A&M University Libraries, the lack of expansion under G9930 created access and filing complications. This case study describes the problem that growing a collection under the unexpanded classification system posed and the solution that was found through the creation of an in-house expansion for G9930.     

全寿命周期视角下的国产大型客机成本评估指标体系研究

以军品中全寿命周期成本的概念出发,根据我国国产大型客机的实际情况,并结合波音、空客等公司发展民用飞机的经验,建立国产大型客机全寿命周期成本评估指标体系,试图以此为我国民用飞机的研制和发展提供评估依据、经验借鉴和决策参考。     

LCC谐振式高升压比超声波换能器驱动

针对传统换能器驱动电路带换能器负载和不带负载时压差过大的问题,提出了一种新的换能器驱动电源。在分析和推导补偿拓扑的基础上,使用LCC补偿网络的输出与负载无关特性和后级电路谐振匹配网络设计使带空载时阻抗角接近0°,实现高升压比和低压差。通过对一款40 kHz的换能器进行仿真和实验验证了方案的可行性,在高升压比的情况下,使换能器的压差降低至90 V,达到了减少压差的效果。     

“英文超级科技词表”农业综合范畴体系构建初探

英文超级科技词表是一个包含三层结构的知识组织体系,范畴体系为其顶层结构,起到类聚概念、表达词表宏观知识结构的作用。文章以农业领域为例,探索构建“英文超级科技词表”农业综合范畴体系的思路。首先,分别对所遴选的主干、辅助范畴体系进行结构特征比较分析;其次,基于辅助范畴表对农业领域范畴体系进行初步构建;最后,分别将DDC、LCC与所构建的农业专业范畴体系进行比对分析,进而为农业综合范畴体系构建提出指导性建议。     

Efficient SIMD optimization for media processors

Single instruction multiple data （SIMD） instructions are often implemented in modem media processors. Although SIMD instructions are useful in multimedia applications, most compilers do not have good support for SIMD instructions. This paper focuses on SIMD instructions generation for media processors. We present an efficient code optimization approach that is integrated into a retargetable C compiler. SIMD instructions are generated by finding and combining the same operations in programs. Experimental results for the UltraSPARC VIS instruction set show that a speedup factor up to 2.639 is obtained.     

生产者视角下产品生命周期成本的仿真模型研究

从生产者视角将产品生命周期成本划分为设计成本、制造成本和售后服务成本,针对生命周期成本及其成本要素之间相互影响的滞后性与复杂性,利用系统动力学方法构建仿真模型。以广州某液压泵厂的YB-E高性能液压泵为例构建仿真模型,模拟出成本项目与成本要素的变化过程,找出关键成本要素,通过调整关键成本要素的取值进一步研究其对总成本的影响。结果表明,将系统动力学应用于企业LCC控制能较好地反映所研究系统内各成本要素间的复杂关系,指导企业有的放矢的采取成本控制措施。     

分类法在网络信息组织中的应用

传统分类法在组织网络信息资源有着一定优势,文章具体阐述国际三大分类法在网络信息资源组织中的应用情况。     

论LCC的编制原则及类目安排特点

LCC是美国国会图书分类法的英文简称,是美国国会图书馆根据该馆藏书编制的综合性等级列举式图书分类法。它为美国国会图书馆的文献资源提供一个分类目录系统并组织藏书排架,整个体系安排及具体类目设置上都不甚严密。     

An Automated Reclassification Project at the University of Kentucky

ABSTRACT

The University of Kentucky Libraries began use of the Library of Congress Classification System in 1978, leaving the bulk of their older material in the Dewey Classification System. In 1992 during the planning for the new Young Library, the opportunity arose to complete the reclassification of the collection from Dewey to Library of Congress. This paper outlines the process used to reclassify the collection. Unique features of this project were the reliance on automation to reduce the number of person hours needed for reclassifying the materials and the minimal disruption of services to users.