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An increasingly higher temperature is required with the rapid development of airborne remote sensors, giving rise to an urgent demand for a technology or device which can ensure both the uniform temperature and a high heat exchange capacity. This paper, based on the human circulatory system, proposes a thermal control device with a fluid circulation. The device is introduced in detail and an experiment is made to verify its thermal control effects. It is shown that the device has better temperature uniformity and a better heat transfer capability compared to the traditional heating films.

BRT, short for Bus Rapid Transit System, has been an important choice for large and medium-sized cities to reduce the traffic congestion. Since BRT travel can greatly reduce the bus travel time of passengers, it attracts a large portion public bus trips, making BRT station a centralized area with a high density of passengers for public transport. Under the circumstances, accidents such as serious crowd, panic, trample and even casualties may occur in BRT station. It is of great significance to propose an evacuation model for BRT station to provide guidance and advices for evacuation in BRT station. First, by analysing existed computer evacuation simulation models, we propose a new simulation model, in which fine grid is used to model the BRT station and conflict resolution mechanisms and pedestrian movement rules are incorporated. Then, we develop a computer-programming evacuation simulation platform based on the evacuation simulation model. By applying it to Gangding station of Guangzhou BRT, we take a closer look on the laws of evacuation in BRT station. Finally, the simulation provides the details of the dynamic evacuation process clearly; some phenomenon such as bottleneck area and influences of obstacles are directly observed. The results verify the practicability and feasibility of the evacuation model.

An acceleration Feedback(AFB) is introduced to the servo system to improve the dynamic performance of a moving base optoelectronic stability platform.As it is difficult to establish a model for the moving base optoelectronic platform according to a moving object,the proposed acceleration feedback is realized by measuring angle acceleration signals directly.Simulation and analysis indicate that the dynamic stiffness of servo system can be enhanced and the starting and braking performance is improved with the AFB.Experiments show that the capability of resisting friction moment is increased significantly.The capability of resisting periodic disturbance is increased by 9.3db and the overshoot of speed step response is decreased by 4.9%,while the transition process has been greatly improved.The servo system has simpler structure,higher robustness,and shows better universality.

The primary tube of a visible zoom lens and its mounting are designed by UG advanced simulation according to the characteristcs of a wide temperature range(-40-+55 ℃) and little optical axis variation(≤0.2 mrad),and the deformation patterns in different conditions are gotten by using finite element analysis.An estimation way to get the optical axis variation is proposed,by which the more reasonable structure type is obtained.The results from the lens transfer function test and vibration test show that the Modulation Transfer Function(MTF) is above 0.2 and the fundamental frequency is 117 Hz.The practical image is stable and clear,which indicates that the optimized design of zoom lens is reasonable.

In order to improve the measuring accuracy of a steel ring reflective grating,a grating signal compensation system is designed.The system is used to compensate the signal amplitude,DC voltage and the phase of the grating,respectively,for which two grating signals have a better orthogonality.First,according to the sampling method for steel ring reflective grating signals,an electronic processing system is created.And then several compensation algorithms are established aiming at the signal amplitude,DC voltage and the phase.By taking the steel ring reflective grating with 8 192 lp/mm as a platform and the results of testing precision as a basis of adjudication,the proposed signal compensation system is verified.The results show that the precision compensated has been improved by 2.28″ with an increasing magnitude of 50%.Obtained results prove that the signal compensation system is feasible.

A centrifugal coating technology was researched to coating the uniform thickness photoresist on a concave spherical surface.Firstly,the critical factors affecting the uniform of photosensitive resist and the film forming force were investigated.Then,the centrifugal glue adhesive force during the flow state was analysed in the spherical photoresist spin coating down opening based on the hydrodynamic theory.A mathematical model to describe the relationship among the film thickness and centrifuge speed,viscosity of photoresist and the spin coating time was derived.Finally,in order to verify the correctness of the formula,some experiments of photoresist spin coating on the K9 glass concave sphere with a diameter of 120 mm,radius of 300 mm,vector height of 12.5 mm were performed.The experimental results certify that the proposed theory is consistent with the actual situation well.On the theoretical analysis,the uniform film thickness on the inner surface of an entire sphere can be obtained with the disalignment of photoresis pin coating axis and the main axis of electric engine.When the viscosity of photoresist is 1.1~1.9 Pa and the speed of main axis is 3 000-6 000/r·min-1,the uniform film thickness is 0.5~1 μm on a concave sphere.

In order to reduce the influence of vibration on the image quality and precision stability of a airborne electro-optical surveillance platform,a vibration damping design was performed.Based on the detailed analysis of complex damping theory,a two-grade damping system between the inter and outer frames of the platform was designed to isolate the vibration from inter frame to outer frame effectively in view of the shortcoming of the single-stage vibration isolation system.By using the two-dimensional parameter optimization method,the optimum natural frequency ratio fopt and the optimum damping ratio ζopt of the vibration damping system were calculated to be 1.43 and 0.243,respectively.Finally,the vibration damping effect was illustrated through a vibration test.Compared with the previous single-stage vibration isolation system,experimental results show that the maximum vibration transmissibility of vibration damping system is lower by 50%,the frequency range of vibration transmission rate less than 1 is wider,and the amplitude range of transmissibility on high frequency is much better than that of the single-stage vibration isolation system.It is concluded that the vibration damping design is feasible and effective for electro-optical surveillance platforms.

In this paper, a broadband flat sheet reflector antenna array with low-sidelobe is designed and analyzed. This antenna array is composed of 12 elements. By optimizing the configurations of the elements and the Power Dividers, a low-sidelobe is achieved in the band of 800∼1350MHz. The measured results indicate that the VSWR of this antenna array is less 2, the gain is more than 15∼17dBi, the sidelobe level is less than −20dB and the characteristic of patterns well in this band, and the comparative bandwidth is more than 51%. It is of great value in some speacial communication systems.

An optical supporting structure is studied to improve its structure stiffness and reduce the rotate error to meet the requirement of aviation remote sensor. A formula to calculate fundamental frequency is proposed using Rayleigh-Ritz method, and a method of is analyzed. By means of OPTISTRUCT software, the maximum fundamental frequency is converted to object function, the deformation under the gravity and the mass are assigned to state variable, wall thicknesses of the structure are converted to design variables. The analysis and test results indicate that the fundamental frequency of designed optical supporting structure has been improved 37.2 Hz from 96.9 Hz, which guarantee the reliability of the sweep mechanism, and the rotate error is 4.89″, which is satisfied for the rotate accuracy in plunge angle. The method of optimization has a certain instructional significance for the design of supporting structures in aviation remote sensor.

Currently most existing remote controls for consumer electronics use infrared remotes (IR) technology to control devices which Increases the demand for advanced functionality that cannot be supported by existing IR. RF remotes provide new levels of interactivity and convenience for today's digital home when compared to IR remotes. New network protocols: ZigBee RF4CE are helping to make this technology accessible to us. In this paper, we first introduce the architecture and primitives of the ZigBee RF4CE, then present the researches of the Application layer and Network layer respectively. Focusing on the functions of Network layer including: frequency usage service; node initialization service; transmission control service; discovery service; power saving service; pairing service and security service.