Applied Mechanics and Materials Vols. 427-429

Abstract: This paper describes the design and implementation of piping functionality for multi-process micro-kernel embedded operating system on ARM, including overview of message passing and piping, pipe creation, pipe accessing via message passing, and pipe termination. The ways to implement piping for micro-kernel or mono-kernel are markedly different and this paper focuses on the piping implementation for multi-process micro-kernel. At the final, the paper provides a demo example to show the effect of piping. Based on the piping functionality described in this paper, more powerful shell interpreter with piping function can be designed.

Abstract: This paper describes the design and implementation of raw socket for multi-process micro-kernel embedded operating system on ARM, including overview of network socket, key techniques of implementing raw socket, such as socket creation, socket accessing via message passing, and socket closing, etc. At the final, the paper provides a shell command named ping as an example to show the effect, which uses the raw socket to implement the functionalities of sending echo requirement and receiving echo reply of ICMP. Based on the foundation described in this paper, datagram socket and stream socket can be implemented further.

Abstract: In this paper, multi-core photonic crystal fiber couplers are characterized and numerically simulated with Mangan et als theory and beam propagation method. We propose a kind of 1×3 multi-core photonic crystal fiber couplers with broadband characteristics and the identical split ratio within the range from 1300nm to 1800nm. If the proper length of the couplers is chosen, light couple intensity is completely the same by periphery there-core fiber with broadband characteristics. It provides a theoretical basis for the practice of multi-core photonic crystal fiber couplers.

Abstract: Before putting air conditioner into market, it must be checked strictly by inspection department. Balanced ambient room-type calorimeter chamber is used to measure the conditioner performance according to energy balance principle. At present, the principle of conservation of energy is a method with higher accuracy for air conditioner test. In this paper, we focus on introducing the measuring method of condensed water in the test system after explaining the principle of the air conditioning performance test balanced ambient room-type calorimeter chamber. it is used to balance the capacity measured in evaporator air conditioner by controlling the water inflow of the humidifier. In this way, can we achieve precise measuring the cooling capacity of the air conditioner.

Abstract: In traditional EKF algorithm, biased prediction is used to calculate the jacobian matrix, which leads to get an inaccurate covariance matrix and influence the estimated performance. This paper applies Modified Covariance EKF to target-tracking modeling to solve the problem. In this algorithm, jacobian matrix is calculated again with state estimation. Through this way, measured values are used to modify the covariance matrix, which makes it more accurate. Consequently, estimated performance is improved.

Abstract: Traditional mine hoists have the characteristics of using more meters, complex operation and low production efficiency. To solve these problems, this article introduces an intelligent control system for mine hoist. In the system the industrial fieldbus is combined with the wireless network, the communication protocol of a point to multipoint is developed to realize wireless data collection and wireless data transmission between industrial computer with monitoring computers. For the speed control, a compound control algorithm of ant colony algorithm for optimal control and fuzzy self-adaptive PID control is presented to control hoist operation. Actual application shows that the system worked well.

Abstract: In view of the central heating problems for remote, a realization scheme of remote monitoring system for central heating is presented. In this paper, the composition and functions of the heat supply network monitoring center, the heating station monitoring and control system and the wireless communication system are introduced, the control system hardware configuration is discussed. The system has already been used and run in a good effect.

Abstract: An application of a second-order adaptive lattice IIR notch filter for rejection of NBI in direct sequence spread spectrum system (DSSS) is studied . Closed-form analytical expressions for signal-to-noise ratio (SNR) improvement factor and bit error ratio (BER) of the system are derived. The performances of the algorithm have been researched and simulated in MATLAB. The adaptive filter is designed and implemented on FPGA, which is simple to realize. It is shown by the test on hardware circuit that the filter had a capacity of about 21dB for NBI rejection which satisfies the requirement.

Abstract: A compact bandpass filter has been investigated in this paper, the filter has four stepped impedance resonators, six open stubs are loaded on the two inner resonators, by adjusting sizes of six open stubs, a wide passband can be obtained. This proposed filter contributes respectively one transmission zero on either side of the wide passband. The proposed topology is demonstrated with a design operating at 5.205 GHz with 20.2% bandwidth, and more than 20dB of spurious suppression from 0 to 4.26 GHz and from 6.27 to 8.85 GHz is demonstrated in experimental results, which match well with the simulated results.

Abstract: With the process of high integration, low power consumption, small size in the semiconductor industry, resistive RAM has drawn increasing attention. The discovery of the memristor brings much more to this study. These researches focus on resistive switching characteristics of different materials and analysis of resistive switching mechanisms. We discuss the resistive switching mechanisms of different materials in this paper and analyze different materials used in resistive RAM. Finally, simulation of memristor Spice model oriented to resistive RAM has been finished