Borland C++Builder响应Windows消息机制的分析

Windows是一套以消息驱动的操作系统。C++Builder的可视化组件库(VCL)提供了对大多数Windows消息的处理机制,程序开发人员在一般情况下无需理会Windows消息的细节。然而作为一个windows程序开发者,实有必要掌握C++Builder中如何进行Windows消息的捕获。该文阐述了Windows消息的概念,对C++Builder的消息映射机制进行了系统分析,同时结合一个实际范例,仔细说明了其中之技巧。     

The moderating effects of psychological reactance and product involvement on online shopping recommendation mechanisms based on a causal map

The use of the Internet in the daily activities of individuals and firms has become entrenched, and online shopping has become commonplace. However, debates about how online shopping recommendation mechanisms (OREMs) should be designed have not been completely resolved. The challenge with traditional online shopping recommendation mechanisms (TR-OREMs) is that they focus too much on quantitative factors. Thus, they ignore causal interrelationships with qualitative factors that are believed to significantly impact quantitative factors. Considering only quantitative factors and ignoring qualitative ones likely distorts the final recommendation results. Another problem with TR-OREMs is that they ignore the perceived psychological reactance of consumers against the recommended products. Such consumer reactance may be reduced when the causal interrelationships among all the quantitative and qualitative factors are analyzed and incorporated properly into the OREM. To overcome these problems, we propose a causal map – online shopping recommendation mechanisms (CM-OREMs) based on a causal map. We analyzed possible causal relationships among quantitative and qualitative factors and incorporated them in the recommendation process to reduce consumer reactance against the recommendation results. Furthermore, an elaboration likelihood model (ELM) was used to build hypotheses about how the online shopping behavior of consumers is affected by OREMs based on the proposed causal map. Specifically, the performance of the proposed OREM was empirically analyzed by gathering experiment data from qualified respondents who were asked to refer to the proposed OREM before making purchasing decisions via mobile phones. Statistical results showed that the proposed OREMs could enhance consumer decision satisfaction, decision confidence, and attitude toward the recommended products. It could also positively affect consumer purchasing intentions. The OREM had a greater effect on the high-reactance group of participants than on the low-reactance group as well as on a high-involvement product versus a low-involvement product.     

基于主题图的文献资源组织模型及应用研究

文章分析了主题图的相关理论和传统文献组织方法优劣,论证了主题图在文献资源组织中的可行性,提出了基于主题图的文献资源组织模型及构建方法,引申了基于该模型的文献检索、主题导学、个性化资源推荐等应用研究。     

一种自动监测系统异构性解决方案

文章对空气质量自动监测系统的异构性问题进行了分析与研究,提出了＂抽象设备、映射数据、虚拟协议＂的解决方案,将物理设备屏蔽在驱动一级,将抽象设备屏蔽在转换程序一级,将数据按空气质量因子分类型打包传送到组态王对应的寄存器组,实现了不同数据接口、不同数据类型以及不同传送协议下的企业信息自动化。     

短签名技术与安全匿名源路由S~2 ASR设计

提出一种改进的、无需可信第三方的数字短签名技术,解决了无线自组织网络的密钥委托问题,理论分析表明:该签名能够有效抵抗各种伪造攻击,提高了通信安全和执行效率;基于改进的短签名技术和双线性映射陷门构造方案,实现了源目节点的强匿名和双向认证,无需PKG在线支持,减小了通信延时,提高了网络扩展性.     

机会发现中简单场景构造方法研究

场景构造是机会发现过程中的关键活动之一。对机会发现场景的结构进行形式化描述,提出基于布尔相关矩阵并利用聚类分析的方法构造事件簇,进而实现机会发现简单场景构造的思想并给出实现方法。对机会发现场景构造方法性能的评估进行探讨,明确以效率系数作为机会发现场景构造方法的评估标准。实验表明,该方法的效率系数较高。     

地图图幅整饰自动化技术

基于地理信息系统(GIS)平台二次开发的地图图幅整饰不利于移植及功能扩展,针对该问题,分析地图图幅整饰自动化中图廓、方里网、经纬网、注记等内容的实现过程,从底层开发相应的地图图幅整饰库.对现有GIS平台地图图幅整饰功能进行改进,使地图图幅整饰功能不依赖特定GIS平台.该技术可以在土地规划应用中提高制图效率,并能与其他G...     

一种基于子串识别的多模式串匹配算法

多模式串匹配算法是网络内容过滤系统的核心技术。巨大的存储空间开销是制约多模式匹配串算法应用的瓶颈之一。提出一种基于子串识别的多模式匹配算法—HashBOM,该算法利用位哈希表存储模式串的子串信息以大幅度减少存储空间,利用递归哈希函数计算字符串的哈希值以实现快速匹配。理论分析表明,该算法的空间复杂度为O(rm~2),优于基于子串识别的匹配算法BOM的空间复杂度O(mr|∑|log_2mr);该算法搜索匹配过程的平均时间复杂度为O(nlog|∑|)mr/m,与BOM算法相同(其中m为最短模式串的长度,r为模式串的个数,n为待匹配文本的长度,|∑|为字母表的大小)。在随机数据集和真实数据集上的实验表明,该算法的存储空间远远低于BOM算法,而匹配速度与BOM算法相当,非常适合在线实时匹配的应用环境。     

An interactive concept map approach to supporting mobile learning activities for natural science courses

Mobile and wireless communication technologies not only enable anytime and anywhere learning, but also provide the opportunity to develop learning environments that combine real-world and digital-world resources. Nevertheless, researchers have indicated that, without effective tools for helping students organize their observations in the field, the mobile learning performance could be disappointing. To cope with this problem, this study proposes an interactive concept map-oriented approach for supporting mobile learning activities. An experiment has been conducted on an elementary school natural science course to evaluate the effectiveness of the proposed method. The experimental results show that the proposed approach not only enhances learning attitudes, but also improves the learning achievements of the students.     

Effect of high-level content organizers on hypertext learning

This study investigates the cognitive abilities involved in hypertext learning and design approaches that can help users. We examined the effects of two types of high-level content organizers - a graphic spatial map and an alphabetical list - on readers’ memory for hypertext structure. In the control condition, a simple “home” page with no navigational aid was offered. Subjects were asked to read the hypertext with the purpose of learning the content, but in the post test phase they also had to recall the layout of nodes and links. Memory for links and page places varied as a function of condition. When a spatial map was available participants reconstructed more accurate formal structure then in the two other conditions. Participants’ memory about page places was the least accurate in the list condition. Results also indicate that participants use the content organizer when it is available in order to orientate during learning from hypertext documents.Our results prove that a content organizer showing the formal structure can facilitate the spatial mapping process. However, an organizer exposing a different structure than the real one would generate a conflict.