Video-based hypermedia for education-on-demand

Networked Hyper QuickTime (NHQT) is a prototype education-on-demand system for annotated video over the Internet. NHQT uses World Wide Web, Gopher and QuickTime technologies to deliver video streams with embedded uniform resource locators that point to ancillary documents or video streams. NHQT's video-based user interface supports VCR-style playback control, random positioning, content-based searching and automatic resolution of hypermedia links for Internet access     

Fuzzy thermal modeling for MCM placement

This paper introduces a fuzzy analytical model for the optimal component placement of the power dissipating chips on a multichip module substrate. Our methodology considers multiobjective component placement based on thermal reliability as well as routing length criteria. The objective of the coupled placement methodology is to enhance the performance and reliability of the multichip module system by obtaining an optimal cost during multichip module placement. Case studies of the coupled placement are presented. In addition, the thermal distribution of the coupled placement results is simulated using the finite element method.     

Guidelines for hypermedia usability inspection

Our research addresses evaluating the usability of hypermedia systems oth offline (CD-ROMs) and online (Web) - and tries to capture the features that most characterize the specific nature of these systems. In this article, we describe an inspection technique that lets evaluators concentrate on the usability of specific aspects of hypermedia applications, such as information and navigation structuring, media integration and synchronization, and so on, without neglecting the surface aspects. Our technique uses operational guidelines, called abstract tasks (ATs), which systematically drive the inspection activities, allowing even less experienced evaluators to come up with valuable results. As they currently exist, we see ATs as evaluation patterns, which make it possible to maximize the reuse of an evaluator's expertise. That is, reuse takes advantage of previous work, thus reducing the effort to create a new one. ATs support the reuse of an evaluator's know-how. Their goal is to capture usability inspection expertise and to express it in a precise and understandable form, so that others can easily reproduce, communicate and exploit it. Our current work is devoted to extending the AT library to cover specific usability issues related to e-commerce Web sites     

教务管理信息系统的数据库建模

数据库建模是数据库应用系统开发的关键步骤。在传统的结构化系统设计中,将需求分析阶段得到的ER图转化为关系数据库模型,而ER图仅仅着眼于数据。为了提高开发效率。采用面向对象的系统分析和设计方法,用系统分析阶段所获得的UML类图为基础进行数据库的逻辑结构设计,把类图转化为关系数据库模型。UML类图不但对数据建模,而且能对行为建模,这些行为在物理数据库中被设计成触发器和存储过程。在此以已开发的教务管理信息系统的数据库建模为例,讨论基于UML类图的数据库建模的方法与过程,该系统主要实现学生学籍管理和成绩管理。     

基于用户行为的个性化搜索建模

目前的搜索算法普遍忽视了用户的兴趣行为,仅仅依靠表面的关键词来预测用户的搜索偏好,为用户提供系统"自认为"是用户所感兴趣的内容,没有更深层次地解剖用户的真实需求,没有依照用户长久以来的搜索习惯、搜索兴趣为用户定制一个个性化的搜索模型,为此,本文将提出一个针对用户行为的个性化搜索的模型,通过用户在浏览网站时候的浏览行为,例如:浏览该网页的时间、浏览网页的类型、在浏览网页时是否有进一步的行为,如:保存、复制等操作以此来丰富本文所提出的用户的个性化搜索模型,以求能够更准确地贴近用户的真实需要.     

A hypermedia environment for global collaboration

We have developed a hypermedia environment for global collaboration by knowledge workers, which consists of two modules: InterPOD and TeamSmart. InterPOD creates a “meeting room” environment for participants to access and share multimedia information from various sources, while the TeamSmart hypermedia tool supports collaboration on document production by globally dispersed teams     

Navigation modeling from a user services oriented perspective

Traditional methodologies for Web Information Systems (WIS) development, usually propose to obtain the navigation model from the conceptual data model. Our proposal address the problem of navigation model construction under a user services oriented perspective, unlike the traditional methodologies which follow a structural approach to build it. Our method is based on the identification of the conceptual user services, which are specific services required by the user. The obtained models are user services oriented. So, the final navigation model is focused on the services required by the user. One specific route is also identified for each conceptual user service, that guides the navigation of the user through the WIS. In this paper the method is proposed and it is showed through a case study, which shows how the navigation model conceived from a user services oriented approach, is intuitive and user friendly.     

Examining user perceptions of smartwatch through dynamic topic modeling

Since the 2010s, various companies have begun to manufacture wearable smartwatch devices, but the current sales of these products are not impressive. This study investigates how the limitations of the smartwatch are related to perceptual discomforts. Theoretically, this study evaluates the claim that the discomfort that users appear to have with the smartwatch stem from failed remediation. Users perceive the smartwatch more as a set of functional sensors rather than a watch or smartphone. Specifically, from the remediation perspective, the authors asked how users perceive the functions of the smartwatch. This study used dynamic topic modeling for topics on the smartwatch on Reddit. This study reports that the smartwatch has failed to provide a proper way to use the remediated content that it provides. Suggestions for future studies are addressed.     

Does hypermedia really work for tutoring children?

The advent of multimedia technology has produced an explosion of research on the use of computers in education. Indeed, the computer is a rich communication tool that instructors can use for effectively illustrating ideas. However, compared to human communication, computers lack several features needed for satisfactory communication. They don't have analogies to eyes, ears, voice, and hands that humans use for acquiring information; neither can they create different information representations. Graphic, video, animation, and sound use in multimedia systems attempts to overcome these limitations to develop systems that can better communicate and cooperate with humans. Several recently developed hypermedia environments - both online (on the World Wide Web) or offline (on CD-ROM) - promote knowledge acquisition on a wide range of topics and attempt to teach problem-solving abilities in users. However, the basic question of whether hypermedia learning environments actually promote learning is still debatable, Our work here refers to a hypermedia designed for a particular category of users, namely children in a primary school. The hypermedia offers a tutoring component to teach basic logic concepts to children. We call this hypermedia Logiocando, a name obtained by merging two Italian words (Logica Giocando) and meaning "playing with logic." To determine whether this tutoring hypermedia really works (that is, to check its instructional validity), we performed two experiments that evaluated the pedagogical efficiency of the hypermedia in comparison to traditional classroom instruction.     

Knowledge representation and construction in hypermedia environments

Hypermedia information systems, because of their inherent qualities of nonlinearity and associative linking, offer the potential of facilitating enhanced knowledge representation and construction for users. These capabilities will be more fully realized if hypermedia information systems are developed and implemented based on constructivist learning theory. This paper examines the qualities of hypermedia systems that enable them to facilitate learning, discusses the background of current learning theories, and provides a brief view of a possible hypermedia system based on constructivist learning principles that could be developed through the use of intelligent autonomous agents.     

Microcosm TNG: a framework for distributed open hypermedia

Increased amounts of information and users' rising demands for advanced link services pose strong challenges to distributed hypermedia systems. Novel presentation facilities, nontextual digital media, personalization of content and structures, and many more techniques often require complex processing and thus imply new interaction styles. Microcosm TNG (The Next Generation), which is a framework for distributed open hypermedia, offers new mechanisms for desktop and Internet integration. It also promotes a modular approach to authoring hypermedia resources     

An adaptation procedure on envelope statistics for predistorter designs based on statistical modeling methods

There have long been some experiment findings that the behavior of a power amplifier (PA) to digitally modulated stimuli depends on its input statistics. Correspondingly, there have been efforts in characterizing PA behaviors and, more recently, in designing amplifier linearization devices by including the information of envelope statistics or using statistical methods. Superior performance have been reported for resultant linearizer designs compared with similar designs based on conventional approaches. In this brief, an adaptation procedure on envelope statistics will be introduced that can further improve the performance of any predistorter design derived from a statistical amplifier model, or more generally, derived from the sample data sets of the input and the output of the PA.     

Estimation and modeling of QT-interval adaptation to heart rate changes

This paper introduces a new method for QT-interval estimation. It consists in a batch processing mode of the improved Woody's method. Performance of this methodology is evaluated using synthetic data. In parallel, a new model of QT-interval dynamics behavior related to heart rate changes is presented. Since two kinds of QT response have been pointed out, the main idea is to split the modeling process into two steps: 1) the modeling of the fast adaptation, which is inspired by the electrical behavior at the cellular level relative to the electrical restitution curve, and 2) the modeling of the slow adaptation, inspired by experimental works at the cellular level. Both approaches are based on a low-complexity autoregressive process whose parameters are estimated using an unbiased estimator. This new modeling of QT adaptation, combined with the presented QT-estimation process, is applied to several ECG recordings with various heart rate variability dynamics. Its potential is then illustrated on ECG recorded during rest, atrial fibrillation episodes, and exercise. Meaningful results in agreement with physiological knowledge at the cellular level are obtained.     

Modeling logical and temporal synchronization in hypermedia systems

The paper introduces a unified formal model for the complete and accurate specification of both temporal and logical (i.e., link) synchronization within hypermedia distributed and weakly synchronous systems. This new model extends time Petri nets with hierarchical design capabilities and new firing rules. These new firing rules enlighten the notion of hypermedia synchronization through powerful combinations of temporal and logical synchronization. Moreover, the proposed model offers an easy and concise modeling technique of asynchronous events in hypermedia systems     

Dynamic modeling approach to analyze user churn in a large P2P downloading system

Characterizing the features of user churn is crucial to the sustainable development of peer-to-peer (P2P) systems where peers join and leave at any arbitrary time. This paper analyzes the user churn in a P2P downloading system named QQXuanfeng by using the fine-grained log analysis over 60 days. It shows that the online and offline duration is related to up (arrive) time and down (depart) time respectively. A continuous ON/OFF process, which exhibits the diurnal patterns of users, is simulated using the churn model. In particular, the dynamic departure rate is proposed to give insight into the distribution of online duration. Further more, considering the heterogeneity of users, we cluster users based on the similarity of redefined user availability. As an example of application of this model, a high availability overlay is constructed and evaluated based on the clustering.     

T-MPLS统一多业务适配及其OPNET建模

讨论了T-MPLS(transport multi-protocol label.switching)统一多业务适配的必要性,并结合T-MPLS网络的特点,设计了针对不同业务的适配算法.阐述了利用OPNET对T-MPLS多业务进行适配的建模思想和处理过程,对模型的可行性及优势进行了分析.     

中小学教育信息化发展水平模糊聚类分析

学校信息化建设是国家教育信息化的主阵地,中小学教育信息化是基础教育信息化工作的首要任务。针对中小学教育信息化存在的问题,运用模糊聚类分析方法展开研究。首先,构建了由6个一级指标以及其下的24个二级指标构成的指标体系及权重;然后,按照单指标评价、一级指标评价、构造数据矩阵、数据标准化、建立模糊关系矩阵、模糊聚类等聚类分析求解步骤建立了数学模型;最后,通过实例说明指标体系和数学模型的具体应用。文中的研究成果为中小学教育信息化建设提供决策依据,对促进教育信息化发展具有重要作用。     

面向用户需求的有线电视用户离网预警管理系统建设

随着有线电视的一元化收视格局被打破,用户离网问题变得日益严重,如何通过大数据技术和数据挖掘技术来降低用户流失率、提高用户的净推荐值已经成为影响广电运营商发展的首要因素,从有线电视用户收视行为的演变出发,分析了解决有线电视用户离网问题的路径和方法.第一部分介绍了有线电视用户离网现状与原因,从视频收视格局的变化出发,剖析了有线电视用户离网的现状和原因.第二部分介绍了建设有线电视用户离网预警系统的必要性和系统构成,分析了以往离网研究存在的问题,并介绍了格兰研究最新研发的大数据用户离网预警管理系统和online在线服务系统.第三部分介绍了大数据离网预警管理系统的关键技术和物理架构.第四部分介绍了离网预警管理系统的应用,分别阐述了离网用户挽留方案的制定和部门间的无障碍数据应用.     

计算集成身份认证机制

研究集成口令认证、令牌认证、以及生物认证的机制,其创新在于利用协议消息还原用户的信任状,再利用传统的认证技术完成对后者的鉴别,从而提供一种把应用系统与其用户认证技术分离的集成身份认证机制。该机制易于标准化及推广应用,可为多租户的云环境的安全提供更好的安全保障。     

Group-based user pairing for virtual MIMO in LTE

A user pairing method is proposed to improve the throughput gain of virtual multiple input multiple output (virtual MIMO) in 3G long-term evolution (LTE).The approach taken in this study separated the user pairing into four steps 1) the users are divided into two groups according to their signal-to-noise ratio (SNR), and different user pairing metrics are proposed for each group; 2) the scheduler chooses a user for transmitting by a given rule; 3) the scheduler searches the pairing candidate for the selected user in each group; 4) the scheduler chooses the final pairing user from the co-group and crossover-group candidates by using a marginal utility function, to balance fairness and efficiency.The method can improve the throughput of users with high SNR, and guarantee fairness for users with low SNR, so it can be used in 3G LTE systems.The article provides both theoretical analysis and simulation results to support the idea.