Application of SmartBox end-device for medical care using JXTA-Overlay P2P system

During last decade more and more old people live alone and the number of old people that need medical care is increased. The lack of doctors and the increase of the medical cost is becoming a big problem. Therefore, IT-based information systems should be implemented to help solve this problem. In this paper, we present the experimental results and evaluation of the SmartBox stimulation device for medical applications using a P2P system which is based on JXTA-Overlay. The SmartBox is integrated with our P2P system as a useful tool for monitoring and controlling patients activities. We found by experimental results that by SmartBox we can check the patient’s situation. We carried out experiments with a patient in the bed and changed the temperature of the room. From the experimental results, we conclude that the use of SmartBox is an effective way for medical applications.     

Trustworthiness in P2P: performance behaviour of two fuzzy-based systems for JXTA-overlay platform

Peer-to-peer (P2P) networks, will be very important for future distributed systems and applications. In such networks, peers are heterogeneous in providing the services and they do not have the same competence of reliability. Therefore, it is necessary to estimate whether a peer is trustworthy or not for file sharing and other services. In this paper, we propose two fuzzy-based trustworthiness system for P2P communication in JXTA-overlay. System 1 has only one fuzzy logic controller (FLC) and uses four input parameters: mutually agreed behaviour (MAB), actual behaviour criterion (ABC), peer disconnections (PD) and number of uploads (NU) and the output is peer reliability (PR). System 2 has two FLCs. In FLC1 use three input parameters: number of jobs (NJ), number of connections (NC) and connection lifetime (CL) and the output is actual behavioural criterion (ABC). We use ABC and reputation (R) as input linguistic parameters for FLC2 and the output is peer reliability (PR). We evaluate the proposed systems by computer simulations. The simulation results show that the proposed systems have a good behaviour and can be used successfully to evaluate the reliability of the new peer connected in JXTA-overlay.     

A comparison study for two fuzzy-based systems: improving reliability and security of JXTA-overlay P2P platform

The reliability of peers is very important for safe communication in peer-to-peer (P2P) systems. The reliability of a peer can be evaluated based on the reputation and interactions with other peers to provide different services. However, for deciding the peer reliability there are needed many parameters, which make the problem NP-hard. In this paper, we present two fuzzy-based systems (called FBRS1 and FBRS2) to improve the reliability of JXTA-overlay P2P platform. In FBRS1, we considered three input parameters: number of interactions (NI), security (S), packet loss (PL) to decide the peer reliability (PR). In FBRS2, we considered four input parameters: NI, S, PL and local score to decide the PR. We compare the proposed systems by computer simulations. Comparing the complexity of FBRS1 and FBRS2, the FBRS2 is more complex than FBRS1. However, it also considers the local score, which makes it more reliable than FBRS1.     

P2P data replication and trustworthiness for a JXTA-Overlay P2P system using fuzzy logic

P2P systems are very important for future distributed systems and applications. In such systems, the computational burden of the system can be distributed to peer nodes of the system. Therefore, in decentralized systems users become themselves actors by sharing, contributing and controlling the resources of the system. This characteristic makes P2P systems very interesting for the development of decentralized applications. Data replication techniques are commonplace in P2P systems. Data replication means storing copies of the same data at multiple peers thus improving availability and scalability. The trustworthiness of peers also is very important for safe communication in P2P system. The trustworthiness of a peer can be evaluated based on the reputation and actual behaviour of peers to provide services to other peers. In this paper, we propose two fuzzy-based systems for data replication and peer trustworthiness for JXTA-Overlay P2P platform. The simulation results have shown that in the first system, replication factor increases proportionally with increase of number of documents per peer, replication percentage and scale of replication per peer parameters and the second system can be used successfully to select the most reliable peer candidate to execute the tasks.     

IT infrastructure services as a requirement for e-learning system success

Evaluation of e-learning systems success is an essential process in managing and developing these types of systems. There are still arguments about the factors can be used to evaluate the success of e-learning systems. Inadequate attention has been paid to investigate the role of IT infrastructure services as a foundation to create the success of e-learning systems. The focus of this study is the role of IT infrastructure services in terms of the success of e-learning systems. A model is proposed which includes five constructs: IT infrastructure services; perceived usefulness; user satisfaction; customer value; and organizational value. A quantitative study was conducted at an Australian University, with survey responses from 110 Academic staff members and 720 students who use the e-learning system. The empirical study confirmed that an IT infrastructure services is a valid and reliable construct to measure e-learning systems success. In addition, this study provides evidence of the critical role of IT infrastructure services in the success of e-learning systems via its significant effect on perceived usefulness, user satisfaction, customer value, and organizational value.     

Data mining for adaptive learning in a TESL-based e-learning system

This study proposes an Adaptive Learning in Teaching English as a Second Language (TESL) for e-learning system (AL-TESL-e-learning system) that considers various student characteristics. This study explores the learning performance of various students using a data mining technique, an artificial neural network (ANN), as the core of AL-TESL-e-learning system. Three different levels of teaching content for vocabulary, grammar, and reading were set for adaptive learning in the AL-TESL-e-learning system. Finally, this study explores the feasibility of the proposed AL-TESL-e-learning system by comparing the results of the regular online course control group with the AL-TESL-e-learning system adaptive learning experiment group. Statistical results show that the experiment group had better learning performance than the control group; that is, the AL-TESL-e-learning system was better than a regular online course in improving student learning performance.     

e-Learning系统支撑平台的实现

简要地介绍了e-Learning技术标准,分析了现有支撑平台,根据实际开发经验,提出了基于B/S结构的e-Learning课件教学支撑平台实现的思想方法和整体架构,系统采用了Java语言实施程序编码开发,综合多种数据库技术,开发的课件具有交互性跨平台可移植的特点。     

Structured P2P technologies for distributed command and control

The utility of Peer-to-Peer (P2P) systems extends far beyond traditional file sharing. This paper provides an overview of how P2P systems are capable of providing robust command and control for Distributed Multi-Agent Systems (DMASs). Specifically, this article presents the evolution of P2P architectures to date by discussing supporting technologies and applicability of each generation of P2P systems. It provides a detailed survey of fundamental design approaches found in modern large-scale P2P systems highlighting design considerations for building and deploying scalable P2P applications. The survey includes unstructured P2P systems, content retrieval systems, communications structured P2P systems, flat structured P2P systems and finally Hierarchical Peer-to-Peer (HP2P) overlays. It concludes with a presentation of design tradeoffs and opportunities for future research into P2P overlay systems.     

Design of a performance-oriented workplace e-learning system using ontology

E-learning is emerging as a popular learning approach utilized by many organizations. Despite the ever increasing practices of e-learning in the workplace, most e-learning applications fail to meet learners’ needs or serve organization’s quests for success. Significant gaps exist between organizational interests and individual needs when they come to e-learning, which make e-learning applications less goal-effective. To solve this problem, a performance-oriented approach is presented in this study. Key performance indicators (KPIs) are set up to clarify organizational training needs, and help learners establish rational learning objectives. In addition, ontology is used for constructing formal and machine-understandable conceptualization of the performance-oriented learning environment. Using this approach, a KPI-oriented learning ontology and prototype system have been developed and evaluated to demonstrate the effectiveness of the approach.     

Defending a P2P digital preservation system

The LOCKSS (Lots Of Copies Keep Stuff Safe) system allows users to store and preserve electronic content through a system of inexpensive computers arranged in an ad hoc peer-to-peer network. These peers cooperate to detect and repair damage by voting in "opinion polls." We develop a more accurate view of how the network will perform over time by simulating the system's behavior using dynamic models in which peers can be subverted and repaired. These models take into account a variety of parameters, including the rate of peer subversion, the rate of repair, the extent of subversion, and the responsiveness of each peer's system administrator. These models reveal certain systemic vulnerabilities not apparent in our static simulations: a typical adversary that begins with a small foothold within the system (e.g., 20 percent of the population) will completely dominate the voting process within 10 years, even if he only exploits one vulnerability each year. In light of these results, we propose and evaluate countermeasures. One technique, ripple healing, performs remarkably well. For models in which all system administrators are equally likely to repair their systems, it eliminates nearly systemic levels of corruption within days. For models in which some administrators are more likely to repair their systems, ripple healing limits corruption, but proves less effective, since these models already demonstrate superior performance     

Automatic detection of learning styles for an e-learning system

A desirable characteristic for an e-learning system is to provide the learner the most appropriate information based on his requirements and preferences. This can be achieved by capturing and utilizing the learner model. Learner models can be extracted based on personality factors like learning styles, behavioral factors like user’s browsing history and knowledge factors like user’s prior knowledge. In this paper, we address the problem of extracting the learner model based on Felder–Silverman learning style model. The target learners in this problem are the ones studying basic science. Using NBTree classification algorithm in conjunction with Binary Relevance classifier, the learners are classified based on their interests. Then, learners’ learning styles are detected using these classification results. Experimental results are also conducted to evaluate the performance of the proposed automated learner modeling approach. The results show that the match ratio between the obtained learner’s learning style using the proposed learner model and those obtained by the questionnaires traditionally used for learning style assessment is consistent for most of the dimensions of Felder–Silverman learning style.     

P2P网络的准入控制方案

提出了一个P2P网络的准入控制方案。该方案不仅能根据安全需求对节点进行资格审核，屏蔽掉一些不符合安全要求的节点，而且能抵抗Kim等人方案中存在的Sybil攻击和舍谋攻击。此外，该方案还具有当节点进入P2P网络后，如有恶意行为．网络能剔除这些恶意节点等特性。     

P2P网络的准入控制方案

提出了一个P2P网络的准入控制方案。该方案不仅能根据安全需求对节点进行资格审核,屏蔽掉一些不符合安全要求的节点,而且能抵抗Kim等人方案中存在的Sybil攻击和合谋攻击。此外,该方案还具有当节点进入P2P网络后,如有恶意行为,网络能剔除这些恶意节点等特性。     

一种新型P2P邮件系统的研究与实现

提出一种新型点到点 (P2P)E mail系统,详细讨论了其体系结构,描述了该系统发送和接收邮件的机制,讨论了系统原型实现的方式和技术。这种新的体系结构消除了用户对单一服务器的依赖,为用户提供了一个安全可靠的交流平台。     

A comprehensive adaptive system for e-learning of foreign languages

The article presents a proposal, design and implementation of a new approach to adaptive e-learning systems. First, a proposal of a model is presented. This model aims at introducing adaptivity to current e-learning systems, which are rigid and limited in offering a truly personalised learning to individual students. Many of current e-learning systems enable personalised learning. However, in this paper, there is a new, innovative approach proposed for an adaptive personalised e-learning system. The primary area of our research is English as a second language (ESL). Adaptivity in our view is considered as an ability of the system to adapt to student's knowledge and characteristics. This pedagogical perspective requires introduction of such processes that enable to work the pedagogical aspects of teaching/learning. The required processes are of informatics nature. The proposed model was subsequently designed into a real application. Finally, the application was implemented and verified on a real data set. The results are also provided.     

Designing an effective P2P system for a VoD system to exploit the multicast communication

A distributed video-on-demand system (DVoD) with multiple server-nodes is a cost-effective and fault-tolerant solution for a high scalable enterprise video-on-demand (VoD) system. However, such a server-oriented design is highly vulnerable to workload variations given that the service capacity is limited. Peer-to-Peer (P2P) has been introduced as an architectural solution with self-growing capacity. However, the characteristics of a pure P2P system such as the peer transient nature and high network overhead make this kind of architecture unsuitable for a fully interactive VoD system. In this paper, we propose a new efficient integrated VoD architecture, called DPⁿ2P^m$D{P}^{n}2P^m$, that combines DVoD with a P2P system and multicast communications. The DVoD’s server-nodes provide a minimum required quality of service (QoS) and the P2P system is able to offer the mechanism to increase the system service capacity according to client demands. Multicast communication, wherever it is possible, is effectively exploited by our P2P system. In our design, each client is able to send video information to a set of m$m$ clients using only one multicast channel. Furthermore, the collaboration mechanism is able to coordinate a set of clients to create one collaboration group to replace the server, providing an extensive, efficient and low network-overhead collaboration mechanism from n$n$-peers to m$m$-peers. Regardless of the video the client is watching, our P2P scheme allows every active client to collaborate with the server. The P2P scheme is complemented with recovery mechanisms that are able to replace the failed client before affecting the QoS, offering continuous playback. The proposed approach has been broadly evaluated, firstly using a mathematical model to derive the theoretical performance and secondly using a simulation environment to analyze the system’s dynamic behavior, the VCR interaction impact and the client failures. Comparing DPⁿ2P^m$D{P}^{n}2P^m$ with other DVoD architectures and the most relevant P2P delivery policies, we show that our design is an improvement on previous solutions, providing a higher scalability.     

VCG机制在P2P存储系统副本放置中的应用

在点对点（P2P）存储系统副本放置简化模型下引入维克瑞—克拉克—格罗夫斯机制(VCG),建立副本放置模型到VCG机制的映射,设计适当的支付函数以达到副本预放置节点的激励相容,并分析占优战略均衡的存在性,证明了该均衡在多项式时间内可达到均衡。仿真实验表明该机制能达到预放置节点的激励相容。     

Evaluation of a comprehensive P2P video-on-demand streaming system

Video-on-demand (VoD) streaming has recently become a popular service on the Internet, with several companies offering videos to a global audience. However, traditional client/server based VoD streaming systems can be very bandwidth intensive and expensive to maintain, especially for high quality video content. To improve the scalability these systems, the use of peer-to-peer (P2P) networking has been proposed, but despite the efficiency of applications such as BitTorrent for downloading of large files, it is not simple to use P2P techniques for streaming. Problems such as firewalls and freeloaders reduce the efficiency of both types of P2P systems, but for real-time services such as streaming, the result can be reduced playback quality. Other issues include the traffic load imposed on ISPs by P2P networks, which can motivate ISPs to interfere with the P2P traffic. Finally, protecting against malicious modification of content can increase overhead, response times, and startup delays.We consider these issues to be fundamental to the problem of P2P based VoD, but despite the large amount of research that has been done in this field, these issues have largely been ignored. To address this, we present an evaluation of the Streaming P2P Protocol (SPP) architecture. By studying the problem as a whole we have found a simple and comprehensive solution that addresses all the four issues listed above. To show that the system is not only scalable, but also that it can be implemented efficiently, we have used both simulations and experiments on PlanetLab for evaluation. The results show that the combination of cache nodes and use of end-user resources found in the SPP architecture can give a low load on servers and ISPs, even when firewalls are taken into consideration. Furthermore, we observed low startup delays and few playback errors during the PlanetLab experiments. The scalable and low-cost distribution of content possible with the SPP architecture should be suitable for both large-scale commercial distributors and users of community networks with limited resources.     

P2P网络的动态门限准入控制方案

准入控制是仲裁加入申请是否被批准的一个过程。提出一种动态门限准入控制方案即通过改变秘密多项式f（z）的阶t-1达到改变门限值t,使门限值随着网络规模大小化,从而解决了不能灵活改变阀值的局限性。该方案不仅能根据安全需求对节点进行资格审核,屏蔽掉一些不符合安全要求的节点,而且能抵抗Kim等人方案中存在的合谋攻击。