网上经济信息资源分布及检索策略研究

网上信息资源包括 :电子期刊资源、图书信息、报纸资源、学位论文资源、网上政府信息等。检索的方法有很多 ,可直接进入网站或数据库、利用搜索引擎、利用专业信息资源导航系统获取信息资源。     

文档聚类在Web搜索结果中的应用研究

随着互联网的迅猛发展，信息爆炸式增长，产生了信息过载，而在相当程度上，搜索是面临信息过载的唯一选择。但是，现在的搜索引擎缺陷也很明显：一是搜索结果数量庞大；二是搜索结果的线性排列。该文提出采用文档聚类的方法组织搜索引擎的结果，从一定程度上解决了上面的问题。     

网络级发现服务的实施:实践与思考——以北大图书馆“未名学术搜索”为例

近年来,网络级发现服务在图书馆业界迅速兴起。方案选定之后如何实施,就成为发现服务从评估走向应用、从产品推向服务的关键。文章以"未名学术搜索"的实践为基础,介绍了网络级发现服务在北大图书馆的实施背景、目标和组织方式及以下实施要点:本地馆藏的映射与同步,商业电子资源的订购与配置,检索机制的优化,界面和检索框架的客制化,系统发布与服务。     

The use of query suggestions during information search

Query suggestion is a common feature of many information search systems. While much research has been conducted about how to generate suggestions, fewer studies have been conducted about how people interact with and use suggestions. The purpose of this paper is to investigate how and when people integrate query suggestions into their searches and the outcome of this usage. The paper further investigates the relationships between search expertise, topic difficulty, and temporal segment of the search and query suggestion usage. A secondary analysis of data was conducted using data collected in a previous controlled laboratory study. In this previous study, 23 undergraduate research participants used an experimental search system with query suggestions to conduct four topic searches. Results showed that participants integrated the suggestions into their searching fairly quickly and that participants with less search expertise used more suggestions and saved more documents. Participants also used more suggestions towards the end of their searches and when searching for more difficult topics. These results show that query suggestion can provide support in situations where people have less search expertise, greater difficulty searching and at specific times during the search.     

On the compression of search trees

Let X=_x1,_x2,…,_xn$X=x_1\text{,}{x}_2\text{,}\dots \text{,}{x}_n$ be a sequence of non-decreasing integer values. Storing a compressed representation of X that supports access and search is a problem that occurs in many domains. The most common solution to this problem uses a linear list and encodes the differences between consecutive values with encodings that favor small numbers. This solution includes additional information (i.e. samples) to support efficient searching on the encoded values. We introduce a completely different alternative that achieves compression by encoding the differences in a search tree. Our proposal has many applications, such as the representation of posting lists, geographic data, sparse bitmaps, and compressed suffix arrays, to name just a few. The structure is practical and we provide an experimental evaluation to show that it is competitive with the existing techniques.     

整体效率与整体效益最优的数学模型及其求解

考察投资决策问题,从整体效率和整体效益兼顾的角度思考,提出兼顾整体效率和整体效益最优的数学模型（GEGBOM）,基于模型离散形式的决策变量,并按照投资活动的效率值进行排序,提出一种改进的离散和声搜索算法,为满足最低期望产出和最高投资额约束,算法执行过程中进行和声修正策略,数值结果表明了模型及算法的合理性和有效性。     

政治模型下的美国大学校长遴选：以佛罗里达大学为案例

高等教育管理领域有三个经典的组织模型,分别是科层模型、学院模型和政治模型。学院模型在共同治理理念下分析校内共同参与遴选过程具有解释力;科层模型则可用于分析威权治理模式中董事会把遴选作为自身决策事务的遴选特征;而政治模型在解释当前美国公立大学校长遴选工作上具有更大的解释效力。本文以佛罗里达大学2003年校长遴选为案例,分析州治理制度变化、州政治气候以及校内群体博弈对当时校长遴选过程和结构的影响。鉴于大量遴选失败案例,有必要对共同治理传统、公立大学董事会制度和《阳光法案》的影响等进行重新审视并采取果断行动,让州立大学重回为公共利益服务的轨道,走出政治化泥沼。     

货物跟踪信息集成平台中的网络信息搜索算法设计

目前在网络信息搜索算法中,主要有动态规划法、分枝界定法、节约算法、遗传算法等。其中使用最多的是遗传算法,但是传统的遗传算法存在局部搜索能力不足的问题。本文以国际货运代理货物跟踪信息平台网络信息搜索算法为研究对象,对遗传算法进行改进,从而满足实际的业务。     

如何理解分类搜索引擎的类目体系

结合网络资源的特点,分析分类搜索引擎和网络分类法的形成原理。