Applied Mechanics and Materials Vol. 203

Abstract: In this article we plan to get a equation about the concurrence. We select the J-C model, then introduce the double-cavity and double-atom system in this model, and consider the two-atom entanglement. By using the Taylor expansion to calculate the quantum correlations concurrence in this system. Finally we deduce this equation which can predict the sudden death and rebirth of the spin quantum entanglement.

Abstract: This paper presents the design and implementation of a novel pulse width modulation control class D amplifiers chip. With high-performance, low-voltage, low-power and small area, these circuits are employed in portable electronic systems, such as the low-power circuits, wireless communication and high-frequency circuit systems. This class D chip followed the chip implementation center advanced design flow, and then was fabricated using Taiwan Semiconductor Manufacture Company 0.35-μm 2P4M mixed-signal CMOS process. The chip supply voltage is 3.3 V which can operate at a maximum frequency of 100 MHz. The total power consumption is 2.8307 mW, and the chip area size is 1.1497×1.1497 mm2. Finally, the class D chip was tested and the experimental results are discussed. From the excellent performance of the chip verified that it can be applied to audio amplifiers, low-power circuits, etc.

Abstract: As is known to all，Traffic congestion in Beijing city is Increasingly serious.In order to thoroughly analyze the congestion causes of Beijing`s intersection, this paper uses VISSIM to simulate the traffic phenomenon, and in-depth analysis of traffic flow characteristics. Through the simulation of observation, this paper gets the simulation output parameters and basic characteristics of the intersection, and in-depth researches lead to the intersection of the critical causes of congestion, and put forward the corresponding improving countermeasures.

Abstract: This paper, in accordance with the maintenance capacity of “Man-Machine System”, holds the core of the “Man-Machine System” and employs the analysis methods of the complex system, brings forward the model of the three-layer comprehensive evaluation based on fuzzy mathematics, then brings out the methods of the index weight and studies the maintenance capacity’s evaluation algorithm on the foundation of the quantitative analysis. In the last it gives the application of the model and algorithm by using the instances and studies the changing maintenance capacity including the stability and the undulation, which provides one thought for scientifically evaluating the maintenance capacity of “Man-Machine System”.

Abstract: With the wide range of applications of wireless networks, Wireless AP in indoor use of limitation is very big. Reduce the quality of network operation in many cases, This paper analyzes its limitation, put forward several methods to optimize the use of of AP, also put forward a design scheme of an new wireless adaptive AP.

Abstract: In order to explore the unexploded ordnance problem of cluster munitions and find the solutions,M85 Sub-munitions reliability models were established,and the models were simulated by applying the Monte Carlo method.The causes of failure and influencing factors of the dual-purpose improved conventional munitions M85 have been analyzed according to experimental data, so these results show reliability models are right.

Abstract: To meet the increasingly requirements of users in smart home and improve Web service reusable rate, this paper introduces a service composition method based on function decomposition tree. First, this method used function decomposition tree to describe the component relationship of each service component and atomic service. Second, to realize the automation in the execution of service composition, the tree expanded on logic and timing aspect based on OWL-S. In the experiment, it describes the design of function decomposition tree and its transformation to service composition file.

Abstract: Quantum material is one emerging branch of advanced materials. Quantum entanglement is one intrinsic property for quantum material, in particular, in quantum communication. Additivity conjecture is a long standing problem for quantum material to transmit information. This note surveys additivity conjecture in some kinds of forms, and introduces some known results including relations between them.

Abstract: Ultrasonic deicing is a new method of deicing. This paper analyzed and designed a kind of ultrasonic deicing acoustic system, then simulated it with the ANSYS, which is a kind of finite element simulation computer software used to do finite element simulation work. The results indicate that the frequency and mechanical properties of the acoustic system meet the expectant demand.

Abstract: With the continuous improvement of the optical fiber communication rate, polarization mode dispersion (PMD: Polarization mode dispersion) is gradually depth. PMD will cause the light pulse signal wide during transmission, and in the signal transmission process continuous accumulation, damage to the transmission performance of the system, limit the system's transmission rate and transmission distance, PMD began to be the main obstacle which constrained optical fiber communication system upgrade and further development. PMD is a random value and difficult to calculate and test in the actual optical fiber communication systems. Poincare method is intuitive, easy to understand, easy measurement to study the characteristics of the PMD, and avoid a lot of tedious calculations. In the paper, analysis the single-mode fiber and its PMD, and the polarization state transmission process of polarization maintaining fiber and its nonlinear effects using the Poincare method, and simulate PMD characteristics by using Matlab software. Based on these, introduce the measurement principle of an improved Poincare method. Analysis showed that the Poincare sphere is a unique method in the analysis of fiber-optic polarization state transmission. Poincare method for the study of polarization mode dispersion has become an important direction of today's communications field.