Applied Mechanics and Materials Vol. 510

Abstract: A dynamic current method used to measure pyroelectric coefficient (p) for pyroelectric material is described in detail in this paper. The hardware part of the system includes pre-converting circuit, post amplifier circuit, wave-filter circuit, analog-to-digital conversion circuit, temperature test circuit and LCD display panel circuit. The maximum magnification time of amplifier circuit of system is 11300 and the band-stop frequency center for wave-filter circuit is 50 Hz and it's second harmonics 100 Hz. Finally, the measurement system is used to test p parameter of LiTaO₃ crystal slice. The lowest p parameter of LiTaO₃ crystal with a value of 6.08×10^-9 C/cm^{2 o}C is achieved at 32.5°C.

Abstract: On account of the huge fund of material procurement, TISCO need evaluate supplier with suitable model in order to provide decision basis. The article raised a kind of suitable quantitative evaluation model for TISCO material procurement. The process of model design adopted semi-structure interview and improved Delphi method to identify evaluation index, weight and standard. Moreover, using two potential suppliers information and data tested the model. The result displayed that the model could evaluate accurately supplier comprehensive ability, and the evaluation result could provide decision basis for supplier evolution.

Abstract: Production planning and control is becoming important issue in production as well as design process of products to be manufactured. Both of the fields require as accurate as possible computational model to control and predict manufacturing process. Since the variety of techniques is currently introduced, still there exists a gap for improvement. Most of efficiency calculation models addressed to whole production efficiency and model in this paper is dedicated for efficiency of particular product. This model could be also used for product design phase. Application of proposed model would facilitate and simplify the product design and production control.

Abstract: Fault prewarning is important to guarantee the safe and stable operation of Generator Sets (GS). In order to generate prewarnings quickly and accurately before the failures or faults occur in GS, a real-time fault prewarning approach to GS based on dynamic threshold was put forward. This approach was consisted of five steps, that is operating condition (or abnormal event) synchronous, dynamic threshold selection, threshold analysis, fault detection and fault prewarning. The dynamic threshold (closely related to operating condition or abnormal event of GS) was the key of this approach, which can be obtained by means of expertise knowledge discovery. This approach can effectively reduce false positives and false negatives for the faults of GS, whose effectiveness is validated by the applications and practices of Gezhouba power plant.

Abstract: The paper give a method of construct a virtual interactive training system for assemble equipment based on virtual reality technology in which trainees can experience how to assemble equipments. A new, simple and quick software solution of "modeling software + programming language" is proposed to design the system. After the actual used by trainees, it show that the system has characteristics of good interaction and strong immersion, the process of assemble equipments is realistic, efficient and convenient. Achieved its purpose of assemble equipments training, and it is a preparation and supplement to assemble actual equipments.

Abstract: ZigBee wireless network technology was introduced in traditional on-line monitoring system, and the wireless online monitoring function was realized in this paper. The system is mainly composed by ZigBee coordinator node and ZigBee sensor network. The network coordinator node is the control center, and its responsibilities are network maintenance and the data processing. The sensor terminal nodes are composed by a variety of sensors and ZigBee wireless module which distributed in monitoring area, and its responsibilities are the data acquisition and transmission. The innovations of this paper are the power supply mode and improving the efficiency. In this paper, the battery power and small CT power was combined for power supply, and the data fusion and the clustering routing algorithm was used to improve the efficiency.

Abstract: The paper presented a goods locations assignment optimization problem of automated warehouse. A hierarchic genetic algorithm (HGA) was designed to solve this problem. The principium of the algorithm was introduced and a representative result and the analysis were given. The experiment and the analysis indicate the validity of the HGA to optimization problem in above-mentioned conditions.

Abstract: To solve the semantic representation in data integration system, a novel ontology modeling method was proposed. The relationship between deferent layers including the core ontology layer, the role ontology layer, the goal ontology layer, service ontology layer and the mediator ontology layer in the ontology framework was analyzed, and the implement specification of each layer was given based on UML specification. Experimental result shows that proposed method can improve the degree of accuracy of semantic representation, and has the advantage of good adaptability for structure instability and difference in user needs in the grid computing.

Abstract: In the theory of compreesive sensing, the small amount of signal values can be reconstructed when signal is sparse or compressible.But the reconstruction of noisy image isnt very satisfied.In order to improve the quality of reconstruction image,the nonlinear diffusion filter is used in this paper.From the experiment results,the images reconstructed after nonlinear diffusion filter are better,and the value of PSNR is improved.

Abstract: Typically, online transactions require a significant level of human intervention. Customers undertake the search for products, services, potential vendors and business partners. They evaluate alternatives, decide what goods to buy and when, from which vendor, and how much they are willing to pay for. They engage in potential negotiations, carry out the transactions and so on. As those markets become mature, new products and services, as well as new practices, are beginning to appear. There is already ample evidence that agent-based technology will be crucial for these developments, reflecting that both buyers and sellers being vigorously seek techniques to improve their performance. This work surveys several of these agents that help electronic commerce systems by describing their roles in the context of a Consumer Buying Behavior (CBB) model.