Applied Mechanics and Materials Vols. 602-605

Abstract: An advanced genetic algorithm is proposed to apply to test data generation for paths coverage. We advanced the classical genetic algorithm: divided the population into “families”, using the family-in-crossover in each family and PSO-crossover operator between two families which commixed the thought of particle swarm; Then, the fitness function is designed by consider of the difference degree and the degree of approximation, and the model of the advanced genetic algorithm applying to test data generation for paths coverage is given in detail. Finally, the proposed algorithm is applied to a benchmark program, and compared with previous algorithms; the results show that the proposed algorithm is obviously advantageous in the number of generations and time consumption.

Abstract: This paper analyses the security risks of the internal and external enterprise computer network, points out that the internal internet security of enterprise should focus on prevention which includes a variety of network security technology and the establishment of logging and review system. This paper also discusses the main technology of external internet security prevention such as firewall technology and encryption technology and so on and provides some suggestions about risk management and network security for some small and medium enterprises.

Abstract: There are often complex dependency relationships between systems in a system of systems (SoS), which present great challenges for SoS operability analysis. Functional Dependency Network Analysis offers the capability to evaluate the effect of both topology and of the possible degraded functioning of one or more systems on the operability of each node in the SoS. But there are some insufficiencies in the method, so here we give exact definition to self-effectiveness, which includes absolute self-effectiveness and relative self-effectiveness. Then according to the new definitions we show the detail calculation equations. Finally we we take the application of Guariniello and DeLaurentis’s five-node aerospace network for example, and compare the results with theirs. Comparative results show that their results are larger than the exact outcome, and our version give the authentic outcomes.

Abstract: In this paper, output near fields of nanowires with different optical and structure configurations are calculated by using the three-dimensional finite-difference time-domain (3D FDTD) method. Then a nanowire with suitable near field distribution is chosen as the probe for scanning dielectric and metal nanogratings. Scanning results show that the resolution in near-field imaging of dielectric nanogratings can be as low as 80nm, and the imaging results are greatly influenced by the polarization direction of the incident light. Compared with dielectric nanogratings, metal nanogratings have significantly enhanced resolutions when the arrangement of gratings is perpendicular to the polarization direction of the incident light due to the enhancement effect of the localized surface plasmons (SPs). Results presented here could offer valuable references for practical applications in near-field imaging with nanowires as optical probes.

Abstract: In order to automatically identify the mobile phones' reviews that the users comment on the mobile phone on the internet and obtain valuable information from the reviews, this paper presents the process of constructing ontology for the mobile phones' reviews and preliminarily establish a domain ontology of the mobile phones' reviews. The ontology construction adopts the Protégé tool and the Seven Steps method of Stanford University research. The ontology can provide convenience for the semantic information mining on Web mobile phones' reviews, and it can provide a new method to effectively mine the use feelings of the phone from a large number of mobile phone users' reviews.

Abstract: This paper introduces the general model of Markov repairable system, combined with the typical design of 750kV substation communication system, put forward the Markov general model for 750kV substation communication system, a communication system reliability evaluation system based on the state of the equipment. Sensitivity analysis of the equipment failure rate and repair rate parameters on the system reliability, the failure rate and repair rate impact on system reliability, to develop communication system state maintenance, and provide a method to improve the reliability of system.

Abstract: The NOSQL database to support data and high concurrent read and write,scalability and high availability features in a distributed storage system which has been applied widely. In this paper, through the research of load balancing in distributed storage system,and it proposes the consistent hashing algorithm and the virtual node strategy, in order to improve the load balancing of the system and increase the cache hit ratio. For the load balancing principle of NOSQL and SQL Server, analysis and comparison of the experimental data.The result shows that, with the increase of the number of virtual nodes, the cache hit ratio of NOSQL is higher than the cache hit ratio of SQL Server.

Abstract: Architecture design is an important part of the top-level system design, which is related to the development efficiency and quality. Description framework is how to describe the ideas and methods of architecture framework, which help relevant system research personnel understand the architecture. This paper analyzes and summarizes the model of the architectural framework home and abroad, combined with the current development of information technology and information system building needs, which uses the ability to guide the construction, and uses the demand to tract the function. Studying process of building the "new three mutual" (NTM) architecture description framework, this paper designed and completed a six-view architecture framework work, which is more responsive to the current needs of information systems development.

Abstract: In multiattribute decision making, it is critical to indentify the importance degree of attributes before the overall assessment of the alternatives. In this paper, we give a measurement of importance degree of attributes based on knowledge discovery in the decision information system, which satisfies the conditions of fuzzy measure. Further, we construct an evaluation model combined Choquet integral with the importance degree measure. The case study illustrates the validity and the effectiveness of the method.

Abstract: With the rapid development of DOA (direction-of-arrival) estimation methods, the existing beamforming technologies still have the problem of a way to balance high spatial resolution and robust performance. The aperture extension characteristics of fourth-order cumulants is used to raise the spatial resolution of the array in this paper. By using the structure of minimum redundancy array, the calculation of the fourth-order cumulants matrix can be reduced. Simulations of the properties of fourth–order cumulants beamforming method are analyzed in this paper, including the resolution analysis, multi-sources analysis and error analysis. Simulation results show that the fourth-order cumulants beamforming method has a higher spatial resolution than the conventional beamforming method without increasing the number of the array sensors.