共查询到19条相似文献，搜索用时 187 毫秒
1.
类实现了数据及对数据操作的封装,对数据而言增加了它的安全性.但是对于类外的函数及其他类的成员函数却很难访问到被类封装起来的数据成员.针对这种情况,介绍两种访问类内数据成员的方法. 相似文献
2.
详细介绍了基于.net技术的古汉语网络教学平台的设计过程,重点论述了在.net应用程序中实现数据访问功能的通用数据访问类的设计,给出了一个数据访问类的应用例子. 相似文献
3.
王秋梅 《洛阳工业高等专科学校学报》2004,14(3):38-40
介绍C 中，不通过类的接口而对其数据成员进行访问的新方法．该方法根据C 对象模型的特点，通过一个指向待访问的数据成员的指针和一个指向全局（或静态）变量的指针，分别获得待访问的auto类型数据成员指针和静态数据成员指针，从而实现了对类的数据成员的访问，该方法同时说明了类提供的保护和封装对数据成员的安全是不可靠的。 相似文献
4.
秦虎锋 《和田师范专科学校学报》2007,27(6):206-207
文章介绍了利用VB.NET强大的类开发功能,及利用ADO对象动态访问Access数据库,把ADO访问数据的方法编成组件,封装起来,方便软件开发者访问数据,提高开发效率。 相似文献
5.
ADO.NET是.Net框架类库提供的一组类,是支持数据库应用程序开发的数据访问中间件.详细介绍了.Net环境下访问关系型数据库和XML两种典型异构数据的实现方法,并强调了在进行数据访问时有关注意事项. 相似文献
6.
嵌入式网络数据库优化访问的关键是对访问目标数据的准确推荐和挖掘,以实现数据的准确检索。提出一种基于模糊C均值聚类的嵌入式数据库并行推荐算法,构建嵌入式数据的数据结构模型,进行数据信息流属性集特征提取。采用模糊C均值聚类算法实现属性分类,以此实现嵌入式数据的库并行推荐和挖掘。仿真结果表明,采用该算法进行数据库访问,精度较高,执行时间较短,性能优越。 相似文献
7.
数据库访问是实现数据挖掘和信息查询的关键技术,传统的数据库访问方法采用关联规则矢量特征提取方法,对大数据差异状态数据库的链路匹配性能不好,访问过程中的数据聚类误差较大。提出一种基于数据链模板匹配的数据库优化访问技术,首先进行数据库的数据结构分析和访问系统的总体结构构建,然后进行数据库访问特征信息流模型构建和特征提取,并采用数据链模板匹配方法进行数据库访问的关联规则信息索引,以提高数据访问过程中的匹配性能。仿真实验结果表明,采用该方法进行数据库访问,数据索引过程中的特征匹配性能较好,数据召回率较高,访问精度较好。 相似文献
8.
ADO．NET中数据库访问技术的研究 总被引：3，自引：0，他引：3
剖析了ADO．NET编程模型的体系结构、类、接口及其数据访问机制，研究了如何运用ADO．NET实现数据库访问的技术，并对通用数据库访问层的接口编程算法进行了探讨。 相似文献
9.
刘兴明 《吕梁高等专科学校学报》2009,25(1)
数据库访问技术是Visual Basic实训环节中的一个难点.本文总结了Visual Basic的三种数据访问技术,通过对ADO技术的分析,说明了ADO技术的明显优势,提出了一种用"类模块"实现数据库访问的方法. 相似文献
10.
通过对Web大数据库的访问,提高数据库的查询和信息调度能力。传统方法采用基于信息流减法聚类和模糊C均值调度的数据库访问算法,对数据库访问过程中的稀疏度均衡能力不好。提出一种基于稀疏度均衡调度的数据库优化访问算法,分析了数据库中海量数据存储结构模型,进行数据融合和冗余信息滤除处理。采用稀疏度均衡调度方法进行特征提取和数据库访问过程中的均衡调度,提高数据查准率。仿真结果表明,利用该算法进行数据库访问的均衡性能较好,数据的查准率和查全率较高。 相似文献
11.
Wolfgang Lehmann 《British Educational Research Journal》2012,38(2):203-218
Human capital theorists perceive of educational expansion as beneficial to individuals, corporations and national economies, while social closure theorists have claimed that inflation of credential requirements maintains traditional status inequalities. In this paper I argue that status inequalities are not only maintained by credential inflation, but also the inflation of extra‐credential experiences. As undergraduate degrees become more common, access to employment and further education opportunities increasingly depend on extra‐curricular and ‘enriching’ educational experiences. Using qualitative data from a longitudinal study of working‐class university students in Canada, I will address the mechanisms by which they have gained or were denied access to such experiences. The data suggest that working‐class students’ relative lack of financial resources and social networks are barriers to the development of extra‐credential experiences, which in turn leads to the change of educational and career plans for some. 相似文献
12.
Impact of class lecture webcasting on attendance and learning 总被引：1，自引：0，他引：1
Tomoko Traphagan John V. Kucsera Kyoko Kishi 《Educational technology research and development : ETR & D》2010,58(1):19-37
The present study investigated the impact of class lecture webcasts on students’ attendance and learning. The research design
employed four data collection methods in two class sections—one with webcast access and another without—of the same course
taught by the same instructors. Results indicated the following four major findings. (1) The availability of webcasts negatively
impacted student attendance but the availability of other online resources such as PowerPoint slides had a greater negative
impact on attendance. (2) Webcast access appeared to nullify the negative effects absenteeism had on student performance.
(3) For most performance measures based on lecture content, more webcast viewing was associated with higher performance. (4)
Most students in the webcast section reported positive learning experiences and benefits from using webcasts, even though
a majority also reported using webcasts for missing a class. In summary, these results collectively suggest that webcasts
could have positive effects on students’ learning experiences and performance, even if class attendance does decline. 相似文献
13.
龚文生 《思茅师范高等专科学校学报》2010,26(3):43-45
ASP开发的Web应用程序中调用Access数据库,在多用户并发访问时有一定的极限,很多时候不能达到实用的要求。通过《学生成绩查询管理系统》开发过程中Access数据库的表由大变小、逐级分类（分班建表）、多表关联查询的方法,有效的提高Access数据库WEB访问速度,使Access数据库WEB多用户并发访问达到完全实用的效果。从实用的角度出发,对开发过程中的经验及ASP代码实例进行分析,对从事ASP中使用Access数据库开发者,有一定的参考价值。 相似文献
14.
Abstract There is considerable evidence of substantial class inequalities in the education system in Ireland. Studies point to the overemphasis on academic achievement leading to an under‐representation of certain class groups at third level institutions. Significant resources have been allocated to establish targeted access initiatives to address this form of social exclusion. This paper reports the findings of a survey of 266 access students from four third‐level institutions in Ireland. The survey identifies the socio‐economic background of access programme participants, their pre‐programme education level and the primary influences, which motivated them to avail of the access tiative. The paper examines the role, which financial considerations play in the initial decision to participate and the sustained participation of access students. The paper proposes some additional policy directions for the access programme. It recommends that the projected reduction in the numbers attending third‐level institutions should be seen as an appropriate opportunity to expand the access initiative and target those experiencing educational disadvantage. 相似文献
15.
Paul Wakeling 《British Journal of Sociology of Education》2005,26(4):505-522
Despite rapid growth in UK postgraduate education and a current focus on issues of access to higher education, consideration of possible social class differentials at the postgraduate level is missing from the sociological literature. Using Higher Education Statistics Agency data, this paper presents a preliminary investigation of the relationship between social class and progression to postgraduate study in England and considers the interplay with other salient variables, including subject of study, institutional type and first‐degree achievement. Evidence of a social class differential in progression to higher degrees is used to test various sociological theories, particularly those proposed by Bourdieu. There is support for the concept of ‘institutional habitus’ developed in recent UK studies. It is concluded that there is scope for further in‐depth empirical research into social class and postgraduate study. 相似文献
16.
PBL教学法提出大学阶段的英语教学应以多学科的社会、人文、科普等综合知识为教学内容,并使知识围绕学习问题实现整合,让学生在合作学习中主动建构这些知识。PBL教学法应用于大学英语阅读教学,主要包括问题准备、资料查阅、小组交流、课堂讨论、评价总结等环节。PBL教学法的应用使得学生能在有意义的知识学习过程中主动地从语言中获取知识,并进一步提高了语言技能。 相似文献
17.
This article is based on a comparative study of working-class students’ experiences in English and Irish higher education. It highlights the lack of comparative studies on this topic based on qualitative research and why filling this gap is important in understanding access and widening participation. Drawing on biographical interviews with 139 people in a range of elite and non-elite institutions, the article discusses similarities as well as some differences between the data from the two countries in terms of class, identity and how working-class students view and value higher education. It maps out how the research relates to recent debates over social class and outlines the theoretical implications of these findings. 相似文献
18.
ZHUHong FENGYu－cai 《上海大学学报(英文版)》2001,5(4):299-307
This paper propses a security policy model for mandatory access control in class B1 database management system whose level of labeling if tuple.the relation-hierarchical data model is extended to multilevel relation-hierarchical data model.Based on the multievel relation-hierarchical data model,the concept of upper-lower layer relational integrity is presented after we analyze and eliminate the covert channels caused by the database untegrity,Two SQL statements are extended to process polyinstantiation in the multilevel secure environment.The system is based on the multievel relation-hierarchical data model and is capable of integratively storing and manipulating multilevel complicated objects(e.g.,multilevel spatial data) and multievel conventional data(e.g.,integer,real number and character string). 相似文献
19.
Ireland has experienced substantial increases in participation in higher education in recent years. This paper examines whether or not increased admission rates between the mid‐1990s and 2000s led to a reduction in social class inequality in access to higher education. We draw on two data sets, one, a dedicated survey of new entrants to higher education in 2004, the other, a combination of the results of a series of school leavers' surveys conducted in the mid‐1990s and early 2000s. We show that the period has been characterised by both continuity and change. Continuity is reflected in persistent social inequalities in access to higher education: the children of higher professionals and farmers, in particular, have maintained their privileged access to higher education. Change is reflected in some closing in relative social inequalities, partly arising as more advantaged groups reach a saturation point in progression to higher education, and partly due to the children of manual workers increasing their participation rates. 相似文献