Key Engineering Materials Vols. 474-476

Abstract: Water-attack is very harmful to pressure pipeline system security. Passive shuttle-type anti-water-attack check valve can adjust its open and close time by hydraulic damper, and cushion the rapid change of liquid momentum in order to protect the pumps and pipelines. The structure and working principle of this passive check valve are introduced, and the dynamics model is set up. The opening and closing characteristics of the model is analyzed, and simulation comparison is done between the flow field and pressure change laws of shuttle-type check valve and those of swing check valve. The simulation result shows that the hydraulic damper works very well, the flow field of passive shuttle-type check valve is symmetrical, the forces acting on the shuttle is balanceable, and shuttle-type check valves can replace swing check valves in many fields.

Abstract: Radar data processing software is a complex system, which has been implemented with mixed language programming using Visual Studio .Net and Visual C++6.0. COM-based software architecture for radar data processing system is proposed in this paper. It provides modular design framework, and integrates modules developed with different programming language and ready-made modules. Firstly, introduce COM technology in brief, then design radar data processing software system framework, finally show the programming examples to explain how to define and refer the COM interfaces. The results show that using COM-based modular mixed language programming is an effective method to realize the radar data processing software system.

Abstract: In order to locate and segment the image of grain bags in the granary reserves, and making full use of the spatial location information of grain bags, a threshold method is proposed base on two-dimensional Fisher criterion. Firstly, a two-dimensional histogram is obtained by the gray value and the local average gray value of the pixels. Then, the two-dimensional Fisher criterion function value is determined from the two-dimensional histogram. When the maximum function value is obtained, the pair of gray values is the threshold which can be the optimal threshold value. Since the traditional two-dimensional Fisher algorithm is always time-consuming in processing image, a novel and efficient algorithm is proposed to reduce the computational complexity by introducing a fast classification program. Experimental results indicate that the two-dimensional Fisher method which can distinguish the various grain bag regions efficiently and reduce the computation time greatly gives a steady performance.

Abstract: Concrete deteriorated severely in the acid deposit environment. To discover the damage mechanism of the material, changes of microstructure of concrete samples exposed to the acidic solution were executed. A batch of cubic concrete samples with the dimension of 10×10×10mm³ was prepared. Acidic solution with pH level of 2.5 was deposed by the mixture of sulfuric and nitric acid solution in the laboratory. Mercury intrusion test, SEM/EDS analyses were performed on the samples exposed to the acidic solution for a certain periods. Pore structure and porosity ratio of the concrete samples were obtained. Microstructure, chemical compounds, elemental distribution in the samples exposed to the acidic solution for various periods are achieved. Development of the micro characteristics of concrete with exposure time is discussed.

Abstract: To simplify the reinforcement design process of double reinforcement beam section, the concept and application of double reinforcement bean section were introduced, and the appropriate application conditions of reinforced beam in practical engineering and the structural design requirements of beams with double reinforcement section designing were analyzed. The results show that the design value of the negative moment, the beam section size and strength grade of concrete shall meet his requirements of the structural design, then the relational expression is derived, applying this formula to judge whether they meet the preliminary requirements before the calculation of beam reinforcement. Compared with the engineering example shows that the design equations is more simple and accurate, but is the upper limit, and the results can provide a reference for the engineering design and related research.

Abstract: A 3-layer topology is proposed to solve the problem of the incompatibility of the traditional topology structure in large-scale WSN. The data communication strategy for each level have been analysed, and an topology control algorithm for top-level is brought up based on the bottleneck-nodes, which will provide higher reliability control for the key-level. The experimental results indicated that, the new topology control strategy will contribute to balance the communication load of the nodes, and the energy consumption in the key-level reduce remarkably.

Abstract: This paper presents a model for automatically generating 3D cartoon ocean water animations in real-time. The dynamic ocean water surface model is modeled by a spectral method. The cartoon rendering process is implemented by multipass on GPU: First, we code normal of ocean model and generate normal map. Next, we extract discontinuities from normal map and smooth it into edge map. Finally we combine the edge map with cartoon shading based on a projective texture mapping. Some experimental results demonstrate the prettiness and efficiency of the presented model.

Abstract: Different consumer demands different quality, which determines that existence of different quality of the same product is reasonable. The article uses two-stage game of fully non-perfect information. Through two-stage game analysis, the article concludes that whether new entrants should enter the market is not only related with the fixed cost of entry, the number of consumers and the highest taste of consumers, but also related to the quality choices of incumbents; after entrants enter the market, the choices of quality are decided by the quality choices of incumbents.

Abstract: Facing the complexity of military operational modeling and the difficulty of operational effectiveness evaluation, based on extended IDEF3, this paper proposes a framework to evaluate operational effectiveness. Bring forward the basic structure of this framework and extend the UOB’s attributes through introducing the combat action effectiveness. By the task decomposition and the "series-parallel connection" model framework aggregation, it can meet the needs of mapping the single combat action effectiveness to task-based operational effectiveness so as to assess the effectiveness of armies aiming at a specific task. Finally, take an air defense brigade performing air defense task for example to prove this framework used to evaluate the operational effectiveness is feasible.

Abstract: In order to utilize solar energy and industry waste heat to reduce electricity consumption in heating, ventilating, air conditioning and refrigerating (HVAC&R) engineering, the authors developed a new style diffusion-absorption refrigeration (DAR) system. It can be driven by heat sources with low temperature, and in which LiNO₃-NH₃-He is used as working fluids and a spray absorber with a solution cooler is designed to enhance the mass and heat transfer, respectively. What presented here is about the modified experiment set and the latest experiment results. The experiments show that the system can start to operate when the temperature of heat source (hot water) reaches to 60°C and it can meet the temperature requirement of air conditioning when heat source temperature varies in the range of 70～83°C. The evaporating temperature varies from 10～-13°C at various absorbing temperatures when heat source temperature reaches the level of 83～95°C. The corresponding refrigeration capacity and coefficient of performance (COP) varies in the range of 1.90～4.22kW and 0.177～0.332, respectively. It is also found that the evaporating temperature, refrigeration capacity and COP are so sensitive to absorbing temperature rather than generating or condensing temperature that the absorbing temperature can be used to regulate the working condition and parameters of the DAR system, e.g. by means of modulating the flow rate of cooling water circulating in the solution cooler equipped to the spray absorber. Thus, in the fields with plenty of solar energy or industry waste heat, the new style DAR system can be considered as an ideal candidate for utilizing low-grade energy, saving energy and reducing emission.