基于属性加密的雾协同云数据共享方案

为解决现有的属性加密数据共享方案粗粒度和开销大等问题,提出一种能保证数据隐私且访问控制灵活的雾协同云数据共享方案(FAC-ABE)。设计属性加密机制,将数据的访问控制策略分为个性化和专业化两种。通过个性化的访问策略,根据用户的经验和偏好,将数据共享给相应的云端。利用雾节点对数据分类,将共享的数据分流,保障数据共享给专业的云服务器。安全分析结果表明,该方案能保障数据机密性,实现更细粒度的访问控制。实验结果表明,用户能将加密开销转移到雾节点上,降低了云端用户开销。     

Stochastic web-based natural language dialog planning for web information filtering

This work addresses natural language dialog planning for an intelligent web filtering model, which lets the user filter search results obtained by a traditional search engine and assists them to find what they really are looking for. Unlike state-of-the-art approaches, a stochastic planning model is proposed for a web-driven dialog system which uses Conditional Random Fields to predict next dialog moves. Experiments with real web users and different interaction settings show the promise of the approach to web-based adaptive planning aimed at information filtering.     

Modeling dynamic recovery strategy for composite web services execution

During the execution of Composite Web Services (CWS), a component Web Service (WS) can fail and can be repaired with strategies such WS retry, substitution, compensation, roll-back, replication, or checkpointing. Each strategy behaves differently on different scenarios, impacting the CWS Q o S. We propose a non intrusive dynamic fault tolerant model that analyses several levels of information: environment state, execution state, and Q o S criteria, to dynamically decide the best recovery strategy when a failure occurs. We present an experimental study to evaluate the model and determine the impact on Q o S parameters of different recovery strategies; and evaluate the intrusiveness of our strategy during the normal execution of CWSs.     

User centric dynamic web information visualization

Distributed search and routing algorithms based on the DHT (distributed hash table) protocol have attracted considerable attention in structured P2P (peer-to-peer) research as a result of favorable properties such as distribution, self-organization, and high scalability. Compared with a traditional C/S (client/server) network, the probability of peers initiating malicious behavior increases dramatically because of their self-governing and dynamic characteristics, which also make it harder to satisfy the peers’ security required by DHT. In this paper, we propose a new secure DHT protocol based on a multidimensional mapping mechanism. This mechanism maps peers to a multidimensional space by dividing the identifiers into groups. Moreover, a series of secure methods and routing algorithms are provided to achieve secure DHT in smaller spaces. Compared with state-of-the-art approaches, the theoretical analysis and experimental results show that the multidimensional mapping mechanism can effectively improve the average success rate of a resource search by inhibiting malicious behavior.     

A hybrid scheme for processing data structures in a dataflowenvironment

The asynchronous nature of the dataflow model of computation allows the exploitation of maximum inherent parallelism in many application programs. However, before the dataflow model of computation can become a viable alternative to the control flow model of computation, one has to find practical solutions to some problems such as efficient handling of data structures. The paper introduces a new model for handling data structures in a dataflow environment. The proposed model combines constant time access capabilities of vectors as well as the flexibility inherent in the concept of pointers. This allows a careful balance between copying and sharing to optimize the storage and processing overhead incurred during the operations on data structures. The mode] is compared by simulation to other data structure models proposed in the literature, and the results are good     

基于Web的数据动态处理界面生成器实现的关键技术研究

从Web应用出发,对于完成能够对数据进行动态处理的界面生成器所需要的几项关键的技术,包括数据库数据及EntityBean数据源的实现、JSP的Tag扩充、控制器事件驱动引擎的实现等内容,研究其实现方法并完成了实例说明。     

A blockchain-based medical data preservation scheme for telecare medical information systems

International Journal of Information Security - With rapid technological development, mobile computing and wireless transmission have become mature. These two technologies can be combined for...     

传感器网络中鲁棒性虚假数据过滤方案

虚假数据攻击不仅误导基站做出错误的决定,同时也会耗尽宝贵的网络资源。提出了一个鲁棒性虚假数据过滤方案(a Robust Filtering False Date scheme,RFFD)。该方案主要包括一个密钥管理架构及与之对应的虚假数据过滤安全机制两个部分。理论分析和模拟实验表明,与SEF方案相比,RFFD方案过滤虚假数据包的性能显著提高。     

PDR: A protocol for dynamic network reconfiguration based on deadlock recovery scheme

Dynamic network reconfiguration is described as the process of replacing one routing function with another while the network keeps running. The main challenge is avoiding deadlock anomalies while keeping limitations on packet injection and forwarding minimal. Current approaches which have a high complexity and as a result have a limited practical applicability either require the existence of extra network resources, or they will affect the network performance during the reconfiguration process. In this paper we present a simple, fast and efficient mechanism for dynamic network reconfiguration which is based on regressive deadlock recovery instead of avoiding deadlock. The mechanism which is referred to as PDR guarantees a deadlock-free reconfiguration based on wormhole switching. In PDR, a particular approach is taken to handle both deadlocks and performance degradation. We propose the use of a packet injection restriction mechanism that prevents performance degradation near the saturation by controlling the network traffic. Further, in this approach, to accurately detect deadlocks, the deadlock detection mechanism is implemented and also improved by using only the local information, thereby considerably reducing false deadlock detections. In the rare cases when deadlocks are suspected, we propose a new technique that absorbs the deadlocked packet at the current node instead of dropping deadlocked packets and re-injects it later into the network. The main advantage of this method is its simplicity and also it does not require any additional buffers in intermediate nodes to handle deadlocks. It requires only some buffer space in the local node to temporarily hold the deadlocked packets removed from the network. Evaluating results reveal that the mechanism shows substantial performance improvements over the other methods and it works efficiently in different topologies with various routing algorithms.     

A pattern classification by dynamic tactile sense information processing

This paper describes pattern classification with an artificial tactile sense. In this method, an object's shape is determined by touching, groping and grasping it with an artificial hand with tactile sense.

A simplified experiment classifying cylinders and square pillars was performed by an artificial hand with on-off switches instead of pressure sensitive elements. Highly reliable results were obtained. In addition, results of a surface groping experiment are given.     

Neural networks for web content filtering

With the proliferation of harmful Internet content such as pornography, violence, and hate messages, effective content-filtering systems are essential. Many Web-filtering systems are commercially available, and potential users can download trial versions from the Internet. However, the techniques these systems use are insufficiently accurate and do not adapt well to the ever-changing Web. To solve this problem, we propose using artificial neural networks to classify Web pages during content filtering. We focus on blocking pornography because it is among the most prolific and harmful Web content. However, our general framework is adaptable for filtering other objectionable Web material.     

一种新的过滤SYN洪水攻击的方法

本文提出了一种新的过滤SYN洪水攻击的方法。这种方法(故意丢弃过滤)通过观察客户的协议一致性行为判定客户的请求是否正常。它的主要思想是故意丢弃每个连接请求上的第一个SYN数据包,后续的SYN只有遵守TCP超时与重传机制才能通过。分析表明,我们的方法能有效地降低攻击的成功率,同时连接建立的延迟也是可以接受的。     

The ATSR data processing scheme developed for the EODC

Precise global measurements of sea surface temperature (SST) are of great importance for climate research and our ability to model the ocean/ atmosphere. The ATSR instrument is an Announcement of Opportunity experimental package on the ERS-1 satellite, and it is designed to measure global SST with the accuracy levels (better than 0·5 K) that are required by modern climate models. The ATSR instrument's ability to meet its demanding performance objectives depends critically upon a number of novel design features. The way in which these features enable ATSR to achieve its measurement objectives are outlined, and the main tasks of the data processing scheme developed for the U.K. Earth Observation Data Centre are described, including in particular, the ways in which the telemetry data are decoded, the brightness temperature images are geolocated, and the scientific products are derived.     

一种改进的动态数据结构软件水印编码方案

在经典的K基数循环链表结构和PPCT结构水印编码方式的基础上,提出了一种新的动态数据结构软件水印编码方案。理论和实验证明,该方案中采用改进的PPCT水印编码结构在多种评价指标上都具有一定的优势,是一个优良的动态软件水印编码方案。     

Real-time network monitoring scheme based on SNMP for dynamic information

An efficient and automated network management is required in large and complex networks since it is very difficult to manage them only with human effort. In response to this need, the Simple Network Management Protocol (SNMP) has been developed and adopted as the de facto standard. Some management information changes with time and the management station needs to monitor its value in real time. In such a case, polling is generally used in the SNMP because the management station can query agents periodically. However, the polling scheme needs both request and response messages for management information every time, which results in network traffic increase. In this paper, we suggest a real-time network monitoring method for dynamic information to reduce the network traffic in SNMP-based network management. In the proposed strategy, each agent first decides its own monitoring period. Then, the manager collects them and approves each agent's period without modification or adjusts it based on the total traffic generated by monitoring messages. After receiving a response message containing the monitoring period from the management station, each agent sends management information periodically without the request of management station. To evaluate the performance of the proposed real-time monitoring method, we implemented it and compared the network traffic and monitoring quality of the proposed scheme with the general polling method.     

A structure-based approach for multimedia information filtering

While multimedia documents are sequentially presented to users, an information filtering (IF) system is useful to achieve a good retrieval performance in terms of both quality and efficiency. Conventional approaches for designing an IF system are based on the user's evaluation on information relevance degree (IRD), but ignore other attributes in system design such as relative importance of the data in a collection of multimedia documents. In this paper, we aim at developing a framework of designing structure-based multimedia IF systems, which incorporates the characteristics of the importance and relevance of multimedia documents. A method of calculating the values of relative importance degree of multimedia documents is proposed. Furthermore, these values are combined into the IRD of multimedia documents to improve the representation of user profiles. An illustrative example is given to demonstrate the proposed techniques.     

A two-stage decision model for information filtering

Information mismatch and overload are two fundamental issues influencing the effectiveness of information filtering systems. Even though both term-based and pattern-based approaches have been proposed to address the issues, neither of these approaches alone can provide a satisfactory decision for determining the relevant information. This paper presents a novel two-stage decision model for solving the issues. The first stage is a novel rough analysis model to address the overload problem. The second stage is a pattern taxonomy mining model to address the mismatch problem. The experimental results on RCV1 and TREC filtering topics show that the proposed model significantly outperforms the state-of-the-art filtering systems.