Advanced Materials Research Vols. 211-212

Abstract: In peer-to-peer (P2P) networks, nodes are quite different from each other in many aspects, such as sharing resources, online time and bandwidth. Some approaches have been introduced to take advantage of the query forwarding and answering heterogeneity such that the high bandwidth and query answering capability of nodes can be fully utilized to improve the system performance. In this paper, we suggest using the online time heterogeneity to improve the search efficiency of P2P networks. In our proposed Differentiated Index (Diff-Index) algorithm, the nodes with long online time will have higher priority to be queried. Because the online time is quite different among nodes, much search traffic can be saved by querying only a small portion of a network. The query success rate can be kept high because the nodes sharing a great amount of resources tend to have long online time. Our simulation results show that the Diff-Index algorithm can save 66 percent of search traffic.

Abstract: Resource sharing is the dominant peer-to-peer (P2P) application on the Internet, allowing users to easily contribute, search and obtain content. A key weakness of most existing P2P systems is the lack of anonymity. In this paper, we present an anonymous p2p resource sharing system, and this system has three desirable features as follows. First, the proposed P2P system makes it impossible for third parties to identify the participants involved. Second, the proposed P2P system can guarantee that only the content receiver knows the content. Third, the proposed P2P system can allow the content publisher to plausibly deny that the content originated from him or her.

Abstract: Control chart can be designed to quickly detect small shifts in the mean of a sequence of independent normal observations. But this chart cannot perform well for autocorrelated process. The main goal of this article is to suggest a control chart method using to monitoring process with different time delay feedback controlled processes. A quality control model based on delay feedback controlled processes is set up. And the calculating method of average run length of control charts based on process output and control action of multiple steps delay MMSE feedback controlled processes is provided to evaluate control charts performance. A simple example is used to illustrate the procedure of this approach.

Abstract: Collaborative product development (CPD) is a dynamic collaborative process. A workflow model supporting CPD can provide a powerful and orderly workflow management for modern product development. This paper studies the requirements of CPD towards the workflow model, establishes a workflow metamodel supporting CPD process, proposes an idea of ontology-based workflow modeling and builds the workflow ontology model, which will strongly support interactive manipulation between the workflow management systems of collaborative product development.

Abstract: WEDM (Wire Electrical Discharge Machining) is an effective method for machining micro gears. In this paper, aiming at WEDM characteristics, the gear design method is discussed. Based on gear meshing theory, the gear tooth profiles are generated. Mesh interference and wire path for WEDM algorithms are presented. Micro gear CAD/CAM software is developed whose functions include gear modeling, interference judgment and wire path generation. Finally a pair of micro gears is manufactured to verify the work in this paper. With the above method, the constraints on some gear parameters can be eliminated and the micro gear design is made more flexible.

Abstract: This paper mainly deals with the target detecting problem of MIMO radar with space time coding (STC) in compound Gaussian environment, which include the correlated Gaussian clutter and uncorrelated Gaussian scattering. The detector based on generalized likelihood ratio test (GLRT) criterion is studied, and two-step design procedure is adopted when the covariance of clutter is unknown. Specifically, a suitable GLRT estimate based on referenced data is inserted into the detector to make fully adaptive. Some numerical results are given, showing that the derived 2s-GLRT of STC MIMO radar can provide a good performance in spikier clutter and the adaptive loss is acceptable.

Abstract: In terms of the characteristics of the oil pipeline leaks, A kind of leak control equipment was developed in which the remote control walking system, the facilities to find and locate pipe and the institutions of oil leakage recovery were designed, the explosion proof problem was solved also. The equipment can effectively raise the maintainability speed of oil pipeline leakiness, reduce an oil product pollution of leakiness to environment, lower the worker's risk and minimize the loss of the oil product leakiness.

Abstract: In this paper, a new embedded numerical control (ENC) system for carton samplemaker based on Windows CE is presented. The hardware design of ENC system based on ARM9 processor S3C2440A and motion control chip MCX314As is discussed principally. Besides, the device driver of MCX314As is developed by using stream interface driver model under Windows CE operating system. Furthermore, the software structure of the ENC system is introduced, and the way how to utilize multi-thread technology to realize the real-time control of the carton samplemaker is also discussed in detail. The system is proved to be good at dealing with multiple tasks processing, real-time and reliability of motion control.

Abstract: In order to improve the welding speed, quality and automation level of thin-walled bellow, on-line detection and tracking welding control technology is proposed which includes on-line detection system and tracking welding control system. Based on laser sensor, on-line detection system can rapidly filter the data, and the data is stored in a queue, the control system which is based on motion control card is developed by using ActiveX controls for programming, VB is used to develop the integrated user operating system, other control tasks are completely integrated on this system to realize real-time welding control bellow. Results showed that the system is reliable and effectively, the automation level of the bellow welding is greatly improved.

Abstract: This paper studied the problem of deadlock performance analysis for collaborative design process model based on extended objective Petri Net (OPN). Firstly, the definition of CSCD extended OPN model based on decision rules has been proposed by analyzing the collectivity requirement for the machinery products collaborative design system to be built. Besides, models for the OPN model of process controlling nets and design unit objective class. Then OPN invariant analysis theory has been adopted to analyze the dynamic performance of deadlock to the part design unit by building its object communication net. The dynamic performance of the whole model could be obtained by analyzing the performance of all the design unit object class.