A novel trust enhanced grid authentication mechanism

To improve trustworthiness in grid authentication, a novel trust enhanced grid authentication mechanism （TEGAM） is proposed in this paper where trust is divided into trust on grid entity （GE） and trust on third party （TP）. In order to obtain precise trust evaluation on GE＇s behaviors, trust on GE is further subdi- vided into trust as service consumer and trust as service provider. Details for the structure of TEGAM and related TEGAM-based authentication process are also given. Simulation results and prop- erty analysis show that, compared with current trust-based grid authentication techniques, TEGAM can not only help establish explicit and dynamic trust relationships among grid entities but also will significantly increase the efficacy of grid authentication.     

A Peer-to-Peer resource sharing scheme using trusted computing technology

Facing the increasing security issues in P2P networks, a scheme for resource sharing using trusted computing technologies is proposed in this paper. We advance a RS-UCON model with decision continuity and attribute mutability to control the usage process and an architecture to illustrate how TC technologies support policy enforcement with bidirectional attestation. The properties required for attestation should include not only integrity measurement value of platform and related application, but also reputation of users and access history, in order to avoid the limitation of the existing approaches. To make a permission, it is required to evaluate both the authorization and conditions of the subject and the object in resource usage to ensure trustable resources to be transferred to trusted users and platform.     

TPM context manager and dynamic configuration management for trusted virtualization platform

It is absolutely critical that trusted configuration management which significantly affects trust chain establishment, sealing storage and remote attestation, especially in trusted virtualization platform like Xen whose system configuration changes easily. TPM （trusted platform module） context manager is presented to carry out dynamic configuration management for virtual machine. It manages the TPM command requests and VM （virtual machine） configurations. The dynamic configuration representa- tion method based on Merkle hash tree is explicitly proposed against TCG （trusted computing group） static configuration representation. It reflects the true VM status in real time even if the configuration has changed, and it eliminates the invalidation of configuration representation, sealing storage and remote attestation. TPM context manager supports TCG storage protection, remote attestation etc, which greatly enhances the security on trusted virtualization platform.     

Study on security enhancement technology for disaster tolerant system

This paper proposes a security enhancement scheme for disaster tolerant system based on trusted computing technology which combines with the idea of distributed threshold storage. This scheme takes advantage of trusted computing platform with trusted computing module, which is provided with such excellent features as security storage, remote attestation, and so on. Those features effectively ensure trustworthiness of disaster tolerant point. Furthermore, distributed storage based on Erasure code not only disposes the storage problem about a great deal of data, but also preferably avoids one node invalidation, alleviates network load and deals with joint cheat and many other security problems. Consequently, those security enhancement technologies provide mass data with global security protection during the course of disaster tolerance. Foundation Items: Supported by the National High Technology Research and Development Program of China (863 Program) (2008AA01Z404), the Science and Technical Key Project of Ministry of Education (108087) and the Scientific and Technological Project of Wuhan City (200810321130)     

BBACIMA： A Trustworthy Integrity Measurement Architecture through Behavior-Based TPM Access Control

Two limitations of current integrity measurement architectures are pointed out： （1） a reference value is required for every measured entity to verify the system states, as is impractical however; （2） malicious user can forge proof of inexistent system states. This paper proposes a trustworthy integrity measurement architecture, BBACIMA, through enforcing behavior-based access control for trusted platform module （TPM）. BBACIMA introduces a TPM reference monitor （TPMRM） to ensure the trustworthiness of integrity measurement. TPMRM enforces behavior-based access control for the TPM and is isolated from other entities which may be malicious. TPMRM is the only entity manipulating TPM directly and all PCR （platform configuration register） operation requests must pass through the security check of it so that only trusted processes can do measurement and produce the proof of system states. Through these mechanisms malicious user can not enforce attack which is feasible in current measurement architectures.     

Clustering of Web learners based on rough set

The demand for individualized teaching from Elearning websites is rapidly increasing due to the huge differences existed among Web learners. A method for clusteringWeb learners based on rough set is proposed. The basic ideaof the method is to reduce the learning auributes prior to clustering, and therefore the clustering of Web learners iscarried out in a relative low-dimensional space. Using thismethod, the E-learning websites can arrange correspondingleaching content for different clusters of learners so that thelearners‘ individual requirements can be more satisfied.     

Secure localization algorithm based on node cooperative for sensor networks

As to the safety threats faced by sensor networks （SN）, nodes limitations of computation, memory and communication, a secure location algorithm （node cooperative secure localization, NCSL） is presented in this paper. The algorithm takes the improvements of SN location information security as its design targets, utilizing nodes＇ cooperation to build virtual antennae array to communicate and localize, and gains arraying antenna advantage for SN without extra hardware cost, such as reducing multi-path effects, increasing receivers＇ signal to noise ratio and system capa- bility, reducing transmitting power, and so on. Simulations show that the algorithm based on virtual antennae array has good localization ability with a at high accuracy in direction-of-arrival （DOA） estimation, and makes SN capable to resist common malicious attacks, especially wormhole attack, by using the judgment rules for malicious attacks.     

A new provably-secure key agreement protocol for roaming in mobile networks

Protocols for authentication and key establishment have special requirements in a wireless environment. This paper presents a new key agreement protocol HAKA （home server aided key agreement） for roaming scenario. It is carried out by a mobile user and a foreign server with the aid of a home server, which provides all necessary authentications of the three parties. The session key can be obtained by no one except for the mobile user and the foreign server. HAKA is based on Diffie-Hellman key exchange and a secure hash function without using any asymmetric encryption. The protocol is proved secure in Canetti-Krawczyk （CK） model.     

Effects of negative emotion and its correlated neural activity on secretory immunoglobulin A

In this study, we investigated how the negative emotional arousal induced by watching a number of unpleasant images altered the concentration of secretory immunoglobulin A （SlgA） in saliva. Although our results found discrepancies among participants＇ SIgA concentration （i.e. some participants＇ SlgA decreased after watching unpleasant pictures, whereas others increased）, further analysis revealed correlations among participants＇ changes in SIgA concentration, their general coping styles and their actual strategies for emotion regulation when perceiving unpleasant pictures, and the event-related potentials （ERPs） associated with viewing unpleasant pictures. The participants whose SIgA increased after watching unpleasant pictures （the ＂Increasers＂） had higher positive coping scores in the Trait Coping Styles Questionnaire （TCSQ） than those whose SIgA decreased （the ＂Decreasers＂）. Also, relative to the ＂Decreasers＂, the ＂Increasers＂ tended to use more emotion regulation strategies, particularly with extremely negative pictures. The amplitude of their late positive potentials （LPPs） exhibited a reverse dissociation pattern for extremely negative pictures versus least negative ones and was related to the cognitive evaluation of the stimuli＇s meaning. In sum, this research revealed the psychological mechanisms by which negative emotional states influence the immune system and the related ERP changes.     

A protocol for fair electronic purchase based on concurrent signatures

E-commerce protocols for the electronic purchase of goods are difficult to design and implement due to their complexity and high security demands. Fairness of such protocols in literature highly depends on an additional TTP（trusted third party）. However, it is difficult to find such a TTP in some situations. In addition, fairness for customers has been neither fully considered nor well satisfied in existing electronic purchasing protocols. In this paper, a new protocol FEP （fair electronic purchase） without a special TTP but an online bank is presented based on a concurrent digital signature scheme. The FEP protocol guarantees fair electronic purchase of goods via electronic payment between consumers, merchants and their online banks. The protocol is practical and the analysis based on the game logics shows that it achieves the properties of viability, fairness, and timeliness.     

EEG-based asynchronous BCI control of a car in 3D virtual reality environments

Brain computer interface (BCI) aims at creating new communication channels without depending on brain’s normal output channels of peripheral nerves and muscles. However, natural and sophisticated interactions manner between brain and computer still remain challenging. In this paper, we investigate how the duration of event-related desynchronization/synchronization (ERD/ERS) caused by motor imagery (MI) can be modulated and used as an additional control parameter beyond simple binary decisions. Furthermore, using the non-time-locked properties of sustained (de)synchronization, we have developed an asynchronous BCI system for driving a car in 3D virtual reality environment (VRE) based on cumulative incremental control strategy. The extensive real time experiments confirmed that our new approach is able to drive smoothly a virtual car within challenging VRE only by the MI tasks without involving any muscular activities. Supported by the National High-Tech Research Program of China (Grant No. 2006AA01Z125) and the National Basic Research Program of China (Grant No. 2005CB724301)     

Analysis and improvement of cross-realm client-to-client password authenticated key exchange protocols

Because cross-realm C2C-PAKE （client-to-client password authenticated key exchange） protocols can not resist some attacks, this paper writes up new attacks on two representative protocols, then designs a new cross-realm C2C-PAKE protocol with signature and optimal number of rounds for a client （only 2-rounds between a client and a server）. Finally, it is proved that the new protocol can be resistant to all known attacks through heuristic analysis and that it brings more security through the comparisons of security properties with other protocols.     

Design and fabrication of superconducting HEB mixer

This paper describes the design and fabrication of superconducting hot electron bolometer （HEB） mixer based on ultra-thin superconducting NbN films. The high quality films were epitaxially grown on high resistance Si substrates. The device was fabricated by magnetron sputtering, electron beam lithography （EBL）, reactive ion etching （RIE）, lithography, and so on. The device＇s resistance-temperature （R-T） curves and current-voltage （I-V） curves were studied. The results of THz response of the device are presented. Y-factor technique was used to measure the device＇s noise temperature. When the device was irradiated with a laser radiation of 2.5 THz, the obtained lowest noise temperature of the device was 2213 K.     

A feedback-based web search engine

Web search engines are very useful information service tools in the Internet. The current web search engines produce search results relating to the search terms and the actual information collected hy them. Since the selections of the search results cannot affect the future ones. they may not cover most people‘s interests. In this paper, feedback informarion produced by the users‘ accessing lists will be represented By the rough set and can reconstruct the query string and influence the search results. And thus the search engines can provide self-adaptability.     

Implementation of transaction level AMBA bus models using systemC

This paper deals with how to implement AMBA bus transaction level modeling in SystemC.There are twom ain techniques used in the whole modeling process,which consist of starting the platform modeling at the transaction level and using the uniformed modeling language-System C.According to the concepts of interface,port and hierarchical channel introduced in SystemC 2.0,the system of master-channel (AMBA bus) slave is created as the architecture of the AMBA bus transaction level model,which can make it more extendable.The port and interface classes of the model that are prone to program are defined in accordance with the SoC hierarchical design methodology,In addition,method calls,not signal communication,are used between different modules in the model,so the higher-level abstraction is achieved and the simulation performance is improved.The AMBA bus transaction level model is analyzed and certified by simulation experiment,and proved to be completely compliant to the AMBA specification 2.0.     

A fair off-line e-cash system with group signature

This paper describes the research results and development of fair off-line e~eash systems so far, and points out that in these systems, the bank can compute the doublespender‘s account secret key, thus the bank can impersonate the double-spender to withdraw from the double-spender‘s account. This article utilizes anonymity control and group signature to address this shortcoming.     

Formal analysis on an extended security model for database systems

In order to develop highly secure database systems to meet the requirements for class B2, the BLP （Bell-LaPudula） model is extended according to the features of database systems. A method for verifying security model for database systems is pro- posed. According to this method, an analysis by using Coq proof assistant to ensure the correctness and security of the extended model is introduced. Our formal security model has been verified secure. This work demonstrates that our verification method is effective and sufficient.     

A four-state memory cell based on magnetoelectric composite

A four-state memory can store four states in each memory cell. We designed a four-state memory cell using Co/PZT magnetoelectric composite and observed a broad magnetoelectric hysteretic output loop on applying magnetic field. Based on magnetoelectric hysteresis, we developed a read method by applying a bias magnetic field on the memory cell. Results gave clearly four-state signals of 15.8, -4.4, 5.5 and -11.3μV, which demonstrated the feasibility of our design.     

Divisional and hierarchical innervations of G. gecko’s toes to motion and reception

As a member of robot families, climbing robots have become one of the research hot-spots in the robotic field recently and Gekko gecko （G. gecko） has been broadly seen as an ideal model for climbing robot development. But for gecko-mimic robots, one of the key problems is how to design the robot＇s foot. In this paper, （1） high-speed camera recording and electrophysiological method are used to observe motion patterns of G. gecko＇s foot when it climbs on different oriented surfaces; （2） nerve innervations of gecko＇s toes to motion and reception are studied. It is found that the five toes of the G. gecko can be divided into two motion and reception divisions, and also its motion and reception are modulated and controlled hierarchically. The results provide important information and exclusive ideas for the foot design and control algorithm of gecko-mimic robots.