16218050
A tool for constructing service replication systems
Service replication as a key to providing high availability, fault tolerance and good performance in distributed systems. However, building a service replication system is a difficult and complex task. This paper describes a tool that mimics the design of the remote procedure call (RPC) system to support building distributed service replication systems. The tool includes an interface definition language for describing a replica group, a language preprocessor and a runtime library system.
2813000
Detecting and tolerating failures in a loosely integrated heterogeneous database system
This article presents the design and prototype implementation of a fault detection and fault tolerance facility based on the reactive system model for a loosely integrated heterogeneous database system running on a network of workstations. The database system consists of a number of fully autonomous databases that, through their willingness, can share some portion of their information. Sensors (functions that expose some part of the state of an object) are placed on individual databases and system objects (such as traders, agents, and other sensors). Other databases and system objects, and applications can subscribe to a sensor and therefore are notified whenever the sensor value changes. The fault detection mechanism uses sensors to monitor individual databases and system objects and to detect database or system faults. The fault tolerance mechanism uses actuators (functions that can change the state of an object) to react on database or system faults.
15320779
Understanding Transition towards Information Security Culture Change
Transitioning towards an information security culture for organisations has not been adequately explored in the current security and management literature. Many authors have proposed how information security culture can be created, fostered and managed within organisations, but have failed to adequately address the transition process towards information security culture change, particularly for small medium enterprises (SMEs). This paper aims to (1) recapitulate key developments and trends within information security culture literature; (2) explore in detail the transition process towards organisational change; (3) adapt the transition process with respects to the key players involved in transition and propose a transition model for information security culture change; and (4) consider how this model could be used by managers and employees of Australian SMEs. A major intention of this paper is to provide academic researchers and practicing managers with an understanding of the transition process towards achieving information security culture change within SMEs.
184418
Self-adaptive clock synchronization for computational grid
This paper presents an innovative method to synchronize physical clocks for a computational grid, in particular for a computational grid linked through the asynchronous Intranet or Internet environments. The method discussed is an asynchronous self-adaptive clock synchronization mechanism. Two strategies for clock synchronisationare introduced. (1), Use continuous time intervals to calculate the precision of clocks, which can reduce the effect of network delay efficiently. (2) Every node synchronizes its clock, with its leader actively. In addition, a node self-adaptive model is presented, and the relationship between the clock precision and synchronization time is induced, hence a node can predict when it should begin the synchronization process. Detailed simulation and extension of this issue are provided at the end of the paper. The presented model is both practical and feasible.
62686547
Estimation of the size and location of multiple area light sources
Most illuminant estimation algorithms worked on point light sources or directional light sources. Little attempt has been made, however, to estimate area light sources. In this paper, we present a novel scheme that estimates the size and location of multiple area light sources using a set of stereo images of a sphere with a shiny surface. The parameters of the area light source are estimated by a novel algorithm which minimizes the matching error between the corresponding specular patches. Experiments on real images show that our method is accurate and robust in estimating the parameters of the area light source.
19007096
A Self-Learning System for Identifying Harmful Network Information
Network information identification is a “hot” topic currently. This paper designs a self-learning system using neural network algorithm for identifying the harmful network messages of both Chinese and English languages. The system segments the message into words and creates key word vector which characterizes the harmful network information. The BP algorithm is taken advantage of to train the neural network. The result of training and studying of the neural network can be applied onto many network applications based on message identification. The result of experiments demonstrates that our system has a high degree of accuracy.
1641445
Clock Synchronization State Graphs Based on Clock Precision Difference
Consistent and stable global states of clock synchronization are very important in distributed and parallel systems. This paper presents an innovative strategy and method to obtain stable global clock synchronization state graphs in asynchronous Internet environments. Our model will introduce the concept of clock precision difference as a means to evaluate running states of all clocks in this system and make this system self-adaptive well. Finally, we introduce the concept of clock precision difference into global states analysis of clock synchronization and construct clock synchronization state graphs in order to evaluate distributed clock synchronization states. We also present detailed simulations of the strategy and mathematical analysis used on real Internet environments.