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In this paper, two improved microstrip-slot transition structures are proposed. The top layer are microstrip lines with two fan-shaped open-circuit terminals, and the bottom layer is the cross-finger slotline which is perpendicular to the microstrip lines, and the short-circuit terminals of the slotline are circular or petal-shaped. These two structures work in the 1–13GHz frequency band. HFSS is used to simulate these two structures, S-parameters and VSWR are compared among the ring slot, petal shaped slot and the original fan-shaped slot. The results show that petal shaped slot transition structure has the best performance. The S11 is less than −19.5 dB and the VSRW is less than 1.23 within 2.5–11.2GHz and 12.4–13GHz.

Aiming at the problem of low target recognition rate on the battlefield of armored troops, the practical application of vehicle-borne radar moving target recognition is briefly described, and the concept of recognition by micro-Doppler feature is introduced in this paper. The research history, current situation and development trend of ground and low altitude target recognition based on micro-Doppler feature are discussed next. At last, the scientific and feasibility of target recognition by micro-Doppler feature is verified from both theoretical and practical aspects.

The stocks of many family firms trading in Taiwan Stock Exchange are holding by the family members to control the company. This study was to investigate the SEO behavior of the family firms from the viewpoint of agency theory.

In this paper, an alternative multi-stage self-preheating burner is presented and initial analyzed through Computational Fluid Dynamics (CFD). The chief advantages of the present design are to create a high temperature inlet air without using other auxiliary heating devices and a high speed jet in the furnace. Details of the flow field, flow velocity, temperature are provided and flue gas recirculation rate are calculated. The present study has been demonstrated that the air preheats effect and flue gas recirculation rate meet the premise condition of MILD combustion.

In this paper, we mainly investigate algorithms of networked control systems with respect to a certain type of three shaft marine gas turbine. Instead of evaluating these algorithms on the gas turbine in real-life, we first construct a platform based the Truetime toolbox under the MATLAB environment and then run simulations on this platform using two mainstream algorithms, i.e. the Earliest Deadline First (EDF) algorithm, the Rate Monotonic (RM) algorithm. Our simulation results support that the EDF scheduling algorithm is able to allocate network resources more evenly than the RM algorithm, and thus it is a better candidate of the real-time scheduling algorithm for the researched gas turbine networked control system.

With the instruction of computational dynamics of multi-body systems theory, considering factor of the crankshaft system with variable inertia, the torsional vibration model of crankshaft system was established. Based on kinetic energy equivalence principle, the variable inertia of crankshaft system was analyzed by computational dynamics of multi-body systems method; and the characteristic relation curve between torsional vibration frequency and crank angle was attained; then the belt type distribution characteristic of critical speed was obtained. The analysis considering the nonlinear factor of variable inertia was complicated, but the result was much more approach to the fact. The whole analysis laid the foundations of diesel structure design, and provided a simple and feasible approach to torsional vibration analysis with variable inertia of other systems.

The traditional marine gas turbine control system usually used hydraulic and electrical control, which could achieve the three main functions of monitoring, control and protection. With the control requirements of the marine gas turbine continuously improved, the use of distributed digital control system was an important development direction. The digital controller was a core part of distributed digital control system. Currently, there was a plethora of low-cost commercial off-the-shelf hardware available for implementing digital controller, such as PowerPC, PLCs and PC-based boards, SoC, ASICS and so on. When considering the construction of complex distributed systems for marine power plant, the ability to rapidly integrate a variety of devices from different manufacturers is essential. In this paper, based on an open architecture, a digital controller was designed in order to verify the gas turbine distributed control system. The gas turbine distributed digital control LAN semi-physical simulation platform which includes multi-smart devices has been established and a distributed system demonstrator that has been developed to explore future distributed control systems.

Modeling and simulation of gas turbines was a hot research direction at home and abroad. In this paper, micro-turbojet JetCAT-P80, a aviation gas turbine, was took as the research object, which the thermodynamic parameters of the various sections and the engine performance parameters of the design conditions were solved with the Matlab software. On this basis, GasTurb, a system-level modeling and simulation platform for gas turbine, was introduced. During a certain simplification of the premise, the simulation model on computer for Jet CAT-P80 aviation gas turbine was established, and the steady performance of the off-design conditions was studied, also the impact of external environment on gas turbine relevant performance parameters was detailed analyzed. The results show that the simulation results accurately reflect the steady state performance of gas turbine, and the error between the simulation result and the gas turbine actual operating parameters was within reasonable limits which verify the correctness and rationality of the model established in this paper.

Modal superposition analysis was used in the calculation of crankshaft dynamic strength and fatigue life based on rigid-flexible multi-body system dynamics analysis and finite element analysis, this paper verified the precision of crankshaft finite element modal by experiment modal analysis, resulted the position of max stress and dynamic variation during the engine working, calculated the dynamic fatigue life of crankshaft using S-N method. It proved that the method of modal superposition analysis getting a perfect effect in dynamic crankshaft strength and fatigue life calculation.

With the instruction of computational dynamics of multi-body systems theory, the system of rigid bodies and rigid-flexible bodies model of the diesel are built using CAE technology. Then the cylinder pressure is measured at some working condition points; the pressure data of the whole process is gained using interpolation method. The boundary condition of unsteady working condition is analysed, and the rational boundary condition is added. The dynamic strength of the diesel is analysed when it works on rated working condition, speedup working condition, and circumgyratetion condition of full rudder. The dynamic stress distributing is gotten in different working condition. The modeling and analysing process can build the basis for optimum design of diesel structure and the study of matching of ship-engine-oar.

CAN-bus was used as the field bus of marine gas turbine distributed net control system. The gas turbine distributed net control semi-physical simulation platform which included multi-smart devices was established. In the Matlab / Simulink simulation environment, a gas turbine net control simulation system was constructed by using TrueTime package. The effect of change on Network latency, network load and network bandwidth to the control system was researched.

In this paper we propose a multi-sensor image registration approach based on edge-correlation. Firstly, edges of images are extracted and the longer edges are coded by modified Freeman. Secondly initializing correlation of chain code is calculated by integrating correlation coefficient and other methods, then the consistency detection succeeds by relative distance ratio histogram clustering detector based on center of edge correlation and angle histogram clustering detector based on average directional angle difference of edge correlation. During the calculation of average directional angle difference of edge correlation, modified histogram approach in this paper is much better than line-fitting approach. Finally accurate edge correlation pair is obtained, and then image registration parameter is attained by applying least square algorithm (LSM) in interrelated parts. The approach presented in this paper can register images of wide translational and rotary range.

Serial Digital Interface (SDI) has become a standard video interface gradually. The former methods to implement the SDI cause much costs and low agility. Aiming at the situation that analogue and digital coexist, this paper uses a FPGA-based way to design the SDI, it mainly expounds the scheme of the SD SDI design, and analyses its structures and function of each module, which is implemented by Hardware Description Language.

Characteristics and requirements of marine gas turbine distributed control system(DCS) were introduced in this paper. CAN-bus was used as the field bus of marine gas turbine DCS. Semi-physical simulation platform of gas turbine DCS local area network(LAN) which included multi-smart devices was established. The networking technologies of many smart devices based on the CAN bus were studied which included the application layer data communication protocol design, system interface programming, network delay analysis, network load characteristics analysis, etc.. The semi-physical simulation test was conducted in a real network environment.

In this paper, we introduced a low-cost scheme for protecting the investment of research and development (R&D) with a single IC. Being with security feature of security hash algorithm (SHA-1), the IC provides secure soft-feature settings method for intellectual property security, intelligent identification of R&D investment.