Yong Ping Hao

Study on Product Family Architecture Dynamic Evolution Based on Product Instances

Product family architecture (PFA) need to keep the dynamic evolution, in order to meet the changing needs of customers and effectively support the mass customization. This paper puts forward the theory of PFA dynamic evolution based on structure semantic unit. The variation of PFA is mainly caused by the changes in component. In the process of evolution, some components of the architecture need to be removed, replaced or added. For this purpose, the concepts of structure semantic and structure semantic unit were proposed. The structure semantic unit is the combination of assembly relationship, assembly constraint, and geometric information of related dimension and the model of components. The corresponding operations (remove, replace or add) of component is ascertained by consumption analysis of part and similarity calculation between structure semantic units.

An Access Control Model for Workflow in Service Oriented Environment

Workflow access control is an important issue in workflow security. Although there exist some standards for security of Web services and access control for services in distributed systems are well studied, there is a lack of comprehensive approach in access control for web services, especially in workflow. This paper proposes a service oriented workflow model and its access control model. The basic authorization unit is task service which is an abstraction of task in the access control model. In this context, we present the dynamic separation of duty based on task services and their conflict relations. Furthermore, we show this model satisfies access control requirements in workflow.

Collaborative Work Heterogeneous Data Sharing and Application Based on Petri Net

Based on profound research of the characters on Petri Net, the concept of collaborative work heterogeneous data sharing (CWHDS) was proposed, and elaborated the modeling processes of CWHDS based on Petri Net. Furthermore, this paper used heterogeneous data queue to serve as the access station of CWHDS, and further discussed the translation and firing rule on Petri Net in relation to heterogeneous data queue. Finally, an application instance of multi-disciplinary collaborative design management system (MCDMS) based on CWHDS was introduced.

Design and Fabrication of Universal Inertial Switch Based on MEMS Technology

Aiming at such defects as the widely distributed threshold and poor universal performance in traditional inertial switch, a MEMS universal inertial switch was designed. The switch consisted of two annular lectrodes, each electrode was suspended by four serpentine flexures and could move freely. There was a gap between the two electrodes and the gap kept the swtich open during non-working state . When the absolute value of acceleration along a particular direction in the x-y plane exceeded a certain threshold value, one of the electrode (the sensing mass) contacted with the other electrode, the ON-state was held and the duration of the ON-state extended because of the flexible distortion of serpentine flexures . The finite element dynamic model was established and simulated in LS-DYNA and the simulation results showed that under the effect of 800g acceleration, the response time and the contact time of the switch were approximately 0.135ms and 20respectively. Compared with other inertial switch, the designed switch exhibited the higher trigger sensitivity and contact reliability. The micro inertial switch was fabricated using the MEMS bulk micromachining process, including the crucial technology of KOH etching, ICP etching spray coating method and so on. The testing system was designed and the shock testing was selected to test the performance of the switch. The test results showed that when the acceleration reached 800g, about 83% switches could work normally.

Development and Research of MEMS

Microelectromechanical system (MEMS) is a new multi-disciplinary research field in recent years, which is an actuator or system composed of micro sensors, micro actuators, micro devices, signal processing system and control system. This paper mainly introduces the development of MEMS, technology characteristics, main processing materials and processing technology. At last it introduces the development and application of MEMS in the fuze system and aerospace system in detail for the future.

A Method of Receiver Circuit in High-Duplicate Pulse Lased Range Finding’s Design and Analysis

In this paper, the two main reasons are introduced such as great varying range of echo signal power and pulse signal error, which affect the pulse laser ranging accuracy and analyzed on the base of the pulsed laser range finding method. For them, the methods are provided that the AGC technology in the receiving circuit is adopt to extend the dynamic range of the receiver, and gain the high precision receiving pulse signal by using high-speed voltage comparator. Then the problems of great varying range of echo signals caused by different measuring distance and contacting the timing circuit are resolved efficiently.

The Design and Analysis of Universal Inertial Switch Based MEMS

In this paper, a novel MEMS inertial switch is designed and characterized for the purpose of crash sensing for ammunition systems in which high-speed response is required for triggering the detonator. In order to keep the same sensitivity in different direction, the structure of an annular proof-mass suspended by four serpentine flexures is designed. The switch can be integrated with electronics, fast-acting，and lack of a requirement for continuous power, and can be used in a wide area. The motion of the inertial switch is analyzed by dynamic simulation under the 700g threshold acceleration in y direction, the simulation results show that the response time is 0.142ms and the contact time of the switch is about 5 , it illustrates that the response time is short enough and the impact time satisfy the ask. The von-mises stress of the structure is calculate, the maximum stress occurs in the serpentine flexures, the value is 60.61 MPa, much less than the yield strength of the silicon, the switch can be used time after time.

Design and Analysis for the Hybrid Capacitance and Micro-Leverage Amplifier Actuator

This new hybrid capacitance and micro-leverage amplifier actuator was based on modifying existing structure and mechanism. That overcame the drawback of small displacement of the capacitance actuator in virtual of the micro-leverage amplifier. The amplifier time of the single micro-leverage amplifier was 4.5. Connect the 1×9 array with nine electrostatic capacitance micro-actuators with the amplifier and form a polymer actuator. The actuator whole size was limited to 4×4 mm, the maximum output displacement was 42μm under 15V voltage input. The pull-in voltage of the actuator array was 19V.

Multi-Level Block Information Extraction in Engineering Drawings Based on Depth-First Algorithm

The problem of multi-level block reference is analyzed for the process of information extraction in engineering drawings. And the relationship of reference blocks has been established. By using depth-first algorithm, the multi-level reference path of blocks and the parameter transformation can be searched. Based on the algorithm, an arithmetic flow is proposed. And the method of coordinate transformation of reference blocks is expounded. The new method has important significance for comprehensiveness and accuracy of information automatic extraction of engineering drawings which contains multi-level reference blocks.

Supply Chain Coordination Based on Revenue-Sharing Contracts under Random Demand

To a two-echelon supply chain system consisting of one manufacturer and one retailer under random demand, the game models about decentralized decision and centralized decision are constructed in which the manufacturer is the leader and the retailer is the follower. The retailer’s optimal purchasing strategies about two conditions above are given and the supply chain expected total profits under unique purchasing strategies of the retailer are compared with. Then the relations of supply chain expected total profit between with applying the revenue-sharing contracts situation and with the centralized decision situation are discussed. And the conditions to realize the supply chain perfect coordinating are defined. Finally, numerical analysis shows that applying the revenue-sharing contract in the decentralized supply chain could not only achieve the maximal overall expected performance but also allow both parties to benefit from it.