Key Engineering Materials Vols. 467-469

Abstract: This paper proposes and implements a comprehensive software system based on agents and mobile agents techniques, which firstly deals with the network admission control and authorization, adopting the traditional password authentication schema and an intelligent, flexible sensor whose kernel is the NDIS-hooking driver. Agent Message Protocol over UDP/TCP is proposed to secure and encrypt the communication data among stationary agents and server components, which eradicates malicious codes embedded or spread in the internal network. In order to avoid the above software agents mangled or destroyed, the proactive method of Grid Scanning model based on the Agent Message Protocol and Address Resolution Protocol can detect and spoof those clients whose agents are mangled; and if the users forge the logon info, this system can prevent the clients escaping from the control with the dual verification mechanism. Finally, the mobile agent infrastructure with flexible and effortless integration with this security system is introduced and implemented, which supports security access to resources on the controllable clients. Such solution in the internal network satisfies the security-related requirements of availability, expansibility, responsibility, and self-defense, as well as the non-security-related requirements of real-time, veracity, stability and flexibility.

Abstract: Three-dimensional computation of spray and combustion in 16V240ZJ diesel engine was performed by CFD numerical simulation tool FIRE. Because of the unceasing change of the temperature and the mixture in the cylinder, traditional performance-prediction method can only supply the limited information. The appearance of numerical simulation brought a bright future for the design and development of the new diesel engine. Combustion is an extremely complex process ,involving flow field, fuel injection and various combustion reactions. By calculus simulation, we have a thorough understanding of the combustion process of 16V240ZJ diesel engine. Through the flow field and concentrative analysis in the cylinder, the effect of advance angle of fuel on combustion process and formation of NOx and soot was investigated. The results show that the advance angle of fuel has a great effect on spray atomization and fuel-air mixture, and consequently influences the combustion and emission. By simulating , we can get the optimal advance angle of fuel for 16V240ZJ diesel engine is 15°BTDC, namely 345°CA, at which, the emissions are fewer ,and the efficiency is better .The CFD simulation has a direct value for optimizing the chamber’s structure and improving the combustion system.

Abstract: This paper proposes a new method that it uses the neural network to construct the solution of the Hamiltion-Jacobi inequality (HJ), and it carries on the optimization of the neural network weight using the genetic algorithm. This method causes the Lyapunov function to satisfy the HJ, avoides solving the HJ parital differential inequality, and overcomes the difficulty which the HJ parital differential inequality analysis. Beside this, it proposes a design method of a nonlinear state feedback L2-gain disturbance rejection controller based on HJ, and introduces general structure of L2-gain disturbance rejection controller in the form of neural network. The simulation demonstrates the design of controller is feasible and the closed-loop system ensures a finite gain between the disturbance and the output.

Abstract: The performance of production cell for motorcycle engine parts is critical for the competitive capacity of motorcycle products. In order to meet the maximum beneficial result with minimum cost, simulation approach is applied to find the best improvement scheme of the production cell. Performance indicators including rate of comprehensive utilization of equipment and rate of utilization of workers are established. Two different production schemes are analyzed based on work study. Flexsim simulation software was used to simulate and evaluate the schemes. The comparative simulation results show that simulation provides an effective way to find the best improvement scheme by evaluating overall performance of the production cell, instead of partial performance evaluation by traditional work study methods.

Abstract: Using carbon nanotubes (CNTs) film as cathode material, the small-area flat lamp (FL) was sealed and fabricated. And the manufacture process for the whole FL was also presented in detail. The pyrolysis process was adopted to grow CNT film directly over the silicon substrate, and the chromium was deposited on the silicon substrate back surface to form the interface layer. After the sintering process for the screen-printed silver slurry, the patterned cathode electrodes were formed on the cathode back plane surface. Using silver slurry as adhesion material, the silicon substrate would be fixed on the cathode electrode. With the splicing method, the CNT film cathode could also be extended on the flat cathode back plane surface. The fabricated small-area FL using CNT film cathode exhibited better field emission property and high luminance brightness.

Abstract: With high-effective screen-printing technique, the diode field emission display (FED) panel with carbon nanotube (CNT) as cathode material was fabricated. For improving the field emission properties, the annular field emitter was developed. The bar cathode indium tin oxide (ITO) electrode was formed by the divided ITO film with the photolithography process. After the sintering process, the printed silver slurry was solidified to form the rectangular ring electrode. The prepared CNT paste was printed to form the cold cathode emitter. Field emission characteristics of sealed FED panel were measured, and the emission image was also presented. A series of low-cost manufacture process was employed in the device fabrication course. The fabricated FED panel exhibited better field emission performance and large emission current.

Abstract: To cope with environment and climate change has become a global focus, so does energy and resource security. For many developed countries it is a breakthrough of promoting economy growth to advocate low-carbon life and develop low-carbon construction materials together. This is also an important element of a country's future integrated ability. There is a synergy relationship of mutual influence and common development between construction materials industry and low-carbon life. The former does contributions for low-carbon life, and then the latter promotes innovation and energy saving in construction materials industry. Finally the building industry in China will presents photograph of a speed and structure, quality, benefit to unite.

Abstract: The growing of P2P applications enriched the resources sharing by network, but it also brought many problems such as occupying network bandwidth, security of personal information. Therefore, the monitor of P2P applications is very important, and P2P protocol identification is the key point. So far since the P2P appeared, new P2P applications and data encryption made the traditional port-based and application layer protocol signature recognition useless. To overcome the shortcomings of current methods, a new P2P identification algorithm is proposed which uses DFI (Deep Flow Inspection) by extracting the various properties of P2P data stream characteristics, and then the data flows are divided into TCP and UDP data sets, finally the support vector machine optimized by particle swarm optimization is used to assort the network data streams, Experimental results of the P2P and non-P2P applications show that this algorithm can identify the HTTP applications 100% and for a variety of P2P applications, the accuracy of classification can also reach to 95%.

Abstract: Asphalt is an organic mixture with complex compounds and chemical structures which will change after exposed to heat, oxygen, and ultraviolet radiation (UV) and make the physical properties worse, especially at low temperature. In this paper, different aging levels (TFOT，UV-6days) of asphalt binders and mixtures with various mass ratio of layer clay powder to asphalt (0,3%,5%) were considered to investigate the low temperature rheological properties of aged asphalt binders and low temperature strength as well as fatigue properties. Dynamic Shear Rheomoter (DSR) and Universal Testing Machine (UTM) were used to evaluate low temperature properties of bitumen and mixture. From the results, after the addition of layer clay powder, the anti-aging properties is greatly improved and low temperature properties can be better maintained compared to base asphalt.

Abstract: Montmorillonite（MMT）is a typical layered silicate. It has been widely used to modify polymers. It improves the thermal, mechanical and aging properties of polymers. The prominent features of MMT modified asphalt concrete are significant for prolonging the service life of asphalt pavement. The profound researches on the service performance and mechanical characteristics of MMT modified asphalt binder and mixtures are important for the application of MMT modified asphalt concrete in practice projects. The effect of MMT on the creep properties of asphalt mixture has been investigated in the research. The result showed that the physical capabilities of MMT modified bitumen was improved evidently. UTM 25 electro-hydraulic servo-universal testing machine was used to do Creep Text, and proper rheological models are employed to describe such characteristics. Results indicated that the visco-elastic properties of the mixtures can be changed by the use of MMT. The revised Burgers model is suitable for the visco-elastic property research of MMT modified asphalt mixtures. The model demonstrated that the retardant visco-elastic property and viscous property of asphalt mixtures containing MMT can be improved, which result in the enhancement of resistance to permanent deformation for MMT modified asphalt mixtures.