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Today, new energy vehicles as low-power and clean means of transportation have been rapid development. Along with the people’s growing requirement for comfort, they should have a comfortable environment under different driving conditions. Therefore, the air conditioning system of high efficiency and energy saving is essential for new energy vehicles. This paper mainly introduces the present status and development trend of air conditioning system on new energy vehicles.

With the improvement of requirements for vehicle comfort, people put forward higher requirements on the noise control of automotive air conditioning. As the power source of the automobile air conditioner, the compressor is also the main noise sources, so it is the major objective of vibration damping and noise reduction. In this paper, with analyzing the noise mechanism of compressor, introduces four identification methods of automotive air conditioning compressor noise source, providing theoretical basis for automobile air conditioning damping and noise reduction.

The behavior of 3d-shell electrons in ZnO-based varistors doped with semiconductor additives has been investigated. The 3d-shell electron details of the varistors can be extracted by a two-detector coincidence system of the Doppler broadening of positron annihilation radiation. It has been found that the 3d electron signal in semi-Z doped varistors is relatively high as compared with other varistors. The nonlinear coefficient of the sample decreases with the d-d interaction, and the leakage current of the specimen increases with the d-d interaction.

In order to study the working features of automotive air conditioning scroll compressor, this paper uses mathematical model of working process to analyze it. After studying working process, a equation of suction volume is given. The thermodynamic model of compression chamber and back pressure chamber includes mass conservation and energy conservation. Based on Hydromechanics, leakage models of radial leakage and tangential leakage are discussed. The model lays a foundation of automotive air conditioning scroll compressor performance simulation.

Coincidence Doppler broadening spectra measurements on ZnO-based varistor doped with semiconductor additives have been investigated, and the proposed samples exhibit different characteristics. The peak of the ratio curve of pure zinc is the highest, the Positron Lifetime in sample a03 doped with ZT is the longest. The maximum probability of the positron-3d electron occurs in sample doped with semi-ZnO (sintered at 1300 °C for 2h with conventional ceramic processing method). The electrical characteristics of the samples and the behavior of positrons in ZnO-based varistor have been discussed.

By accident of a power plant desulfurization CFD Research sprinkler system model to simulate the process of considering the two-way coupling between the droplet atomization, evaporation, with the main flue gas stream. The results showed that x = 3300 sectional arrangement 40 nozzles, high temperature flue gas through a water spray after 10.8m reach x = 14100 section of the temperature has dropped to 358K, before entering the GGH down to 345K, meet an accident situation spray cooling requirements.

Differences of physical properties between matrix and fractured region, size of fractured region and production allocation all affect production characteristics and development effect of fractured gas wells. Building a numerical simulation model of fracture network dual porosity, we studied impacts of these factors in contrast of programs of different parameters. Larger stimulated reservoir volume and higher permeability of fracture network result in good well performances but no meaningful increase in gas production when reaching a certain degree. Therefore, optimization suggestions of size and physical properties of stimulated reservoir volume as well as production allocation are proposed.

This paper describes the composition and working principle of aircraft parts flexible automatic assembly platform, and gives the detailed analysis and design of flexible automatic assembly platform of mechanical structure and motion adjusting control system. The two types of multi plane assembly shows that automatic assembly platform automatic adjusting is reliable, operation control system and motion mechanism runs stable, this system can meet the various needs of automatic assembly platform of aircraft components, and it realizes the work mode of assembly and products in one to many during the aircraft components Assembly process.

On the aim of the designs and realizes of the high-speed image acquisition of FPGA and DSP systematic hardware platform, combine the actual requirement for the subject, on the basis of confirming systematic scheme and design of the system hardware circuit, finishing the design of the systematic printed circuit board and measure the realization of the algorithm on the edge. Including the overall arrangement of the circuit board, designs of the power and ground, design of electric capacity of decoupling, design of transmission line, etc. at last, provided the intact systematic circuit board picture, put forward a method to expand matrix outside, i.e. measure algorithms on the edge that holds the matrix law again. The systematic circuit is simple, dependability is good, the performance-cost ratio is fine, and has certain innovation and common.

A hybrid graph and rule-based method for recognizing machining features is proposed in this paper, which aims to get the machining feature in 3D in-process model construction system. Initially, the attributed adjacency graph (AAG) of the input MBD models is constructed and represented in matrix form. After that, by deleting the convex edges of the AAG, the concave sub-graphs are generated. For obtaining the volumetric features, their concave sub-graphs are matched with the feature template graphs in a pre-defined library; for those which can be generated by sweeping the edge loops, such as open pocket, closed pocket, through pocket and slot, their features are recognized by using rules. In experimental section, an example is given to illustrate the validity and effectiveness of the proposed method.

To reduce the workload for marking the dimensions of in-process models, a method of dimension marking based on manufacturing features for in-process model is proposed. Firstly, the dimension information is extracted from model based definition (MBD) models; secondly, the feature dimension chains are constructed according to the feature location dimension and the process data, when the process data and design data are not coincided with each other; thirdly, the process dimension tolerances are calculated by using the increasing links and the decreasing links of the MBD. In experimental section, an example was given to illustrate the validity and effectiveness of the proposed method.

Coal mine is a dangerous place in which many fatal factors menace miners' life. When some disasters occur, it may be very dangerous for rescuers to go into mine tunnels to search survivors. So developing the coal mine detecting and rescue robot for mine rescue has a very important meaning. In this paper, a system of explosion-proof detecting robot is presented. The structure design methods of robot have been discussed in detail, including robot body, computer control system, explosion-proof and waterproof design of systems, mobile mechanism design and software design. Finally the application results are given.

For the demand of coal mine flood accident emergency rescue, in this paper, a mine-used underwater explosion-proof robot is presented and the composition structure and design method of the robot are discussed in detail. This device combines mechanical design, underwater power plant, intelligent control, energy supply of mobile device and mine explosion-proof technology. It can cruise underwater with the changeable depth, orientation and speed. It can move flexibly and can collect underwater and overwater images. Practical application shows that this equipment is suitable for the emergency rescue and disaster relief work after the coal mine flood.

Attention is put on FDTD algorithm to simulate electromagnetic travelling underground with XFDTD software in this paper to get echo data of underground plant rhizome. A reasonable simulation model is established with some permittivity and conductivity, and choice of grid size and absorbing boundary is supposed to simulate detecting ability for plant rhizome. Adding noise model is supported and wavelet threshold de-noising algorithm is used to process echo signal with noise, and root mean square error (RMSE) is obtained with different SNR. At the same SNR, the relationship of target echo and object size is presented.

A STM32-based embedded system for 3mm wave detector calibration control platform is introduced in this paper. This embedded control system includes noise source control circuit, database circuit, a real time clock circuit, humidity and temperature sensor circuit, PS/2 interface circuit and SD card interface circuit. Experiment results demonstrate that the Embedded system could satisfy the requirement of millimeter wave detector calibration.

As a novel biometric identification technology, human gait recognition has wide applications in public security and other fields. Aiming to solving problems of conventional Time-Frequency analysis of human gait signal, the paper presented a processing method that adopts time-frequency distribution with complex-lag. Firstly, the human walking Doppler signal model and the principle of time-frequency distribution with complex-lag were introduced. Then the signal based on the model was generated and was analyzed utilizing Spectrogram, WVD and time-frequency distribution with complex-lag. The results show that the presented method has the best performance since its high time-frequency concentration and less cross-terms disturbances.

This paper means to provide an innovative design of aero-engine after investigating existing aero-engines. It is a late model power plant design which is based on the watercraft electromagnetic propulsion technology and the theory that in electromagnetic field magnetic field generates Ampere force to current flow and in combination with specific structures of aero-engines. The design principle of this engine is that when the air working medium with high conductivity goes through an arc generator, it will ionize and produce plasma, which actions in the magnetic field that produced by built-in superconducting magnetic and generates forward push. This design will provide a theoretical reserve for future development of aero-engines and has potential market prospects.

A real-time wireless sensor network (WSN) based on Zigbee technology is introduced in this paper. Sensing data, such as atmospheric pressure, temperature, humidity, orientation, illumination, wind speed and direction, can be captured in real time. It is designed with a RF MCU CC2530 and Zstack protocol of TI Corporation. The overall architecture of the system, detailed hardware design, and process of the system software are described in this paper. Experiment results show that this system operates stably, and has small delay, which will have a certain practical value.

A parameter measuring system is introduced in this paper, which is used for recording the temperature and humidity, atmospheric pressure, rotation speed and acceleration, etc. The system uses a 32-bit RISC microprocessor of STM32F103ZET6 based on the core of ARM Coretex-M3 as master chip. And it writes the data recorded to NAND FLASH. After it finishes, it copies the data to host-computer through SD card.

In this paper, a new 1-wire transmission system for the host-slave communication is introduced, which is composed of STM32 embedded host system, CPLD logic control system and PIC slave system. The transmission line is not only for data transmission between host and 32-way slave, but also for power supply for 32-way slave. This paper details the hardware and software implementation method of each component module based on the given system function, and highlights the circuit design method of power and signal transmission on the same line in the 1-wire transmission system. Experiment results are shown in the final chapter.

A mosaic method of based on rotational scan sequence cylindrical barcode which is suitable for metal parts is put forward, which combined the hardware and the software. Firstly, extract the feature points of each serial image based on scale-interaction of Marr wavelets. Then, get the optimal match of feature points with improved image local entropy. Lastly, complete the natural splice of the defect 2D bar code images through the algorithm of three interpolation and multi-resolution spline. The experimental results show that the algorithm could extract the feature points of consistent relative position and quantity after the processes of rotation, brightness, blur and nose, at the same time, assure the splicing efficiency and measurement precision of image mosaic. The method can also better finish the defect bar code recovery caused by curvature deformation.

In this paper, a small aperture Cassegrain antenna of 8mm band detector is optimally designed, whose main reflector diameter is limited at 96mm (diameter less than 30λ). After design and processing, this antenna measured results show its gain is 26dB, the sidelobe level is close to-12dB and-3dB beam-width is 4.8 °.These are consistent with simulation optimization results.

With the background of the Aviation repair service industry, based on the analysis of the disadvantages of the past information technology solutions used in aviation repair management system, combined with the product lifecycle management concept, an aviation repair system structure based on the semantic service oriented architecture was built, which includes resource layer, basic structure layer, implementation layer and application layer. Finally, we discussed business process collaboration between enterprises.

This paper is focused on a millimeter-wave detector system that works at self-heterodyne mode. The detector antenna and MMW front-end are integrated and a weak heterodyne signal is amplified with a low-noise amplifier. After high-speed sampled with a high-speed A/D, digital signal are processed in a FPGA. Some experiment results are shown finally.

For applications of single supply, a digital interface circuit of resolver based on AD2S1200 is designed in a single 5V system. According to the given resolver, the amplification factor and driver capability of excitation signal is calculated and verified. In order to adjust the excitation signals amplitude and provide enough drive current to the resolvers primary winding, an operational amplifier with high current output capability AD8532 is chosen to set an excitation signal buffer circuit which works as a unity gain inverting proportional amplifier. Besides, the design greatly reduces the amount of components which is especially appropriate for the installation in a constriction space. To give a test for the interface circuit, the microcontroller ATmega16 is used to read the 12-bit parallel angle position data of resolver. The test result shows that the interface circuit can not only work well but also obtain an accuracy of angle position within 0.1°.

In this paper, a high-speed data acquisition system based on FPGA is introduced, which has three different channels with one 5Msps sampling rate and 3×256Mb NAND FLASH. This system is controlled by a large scale FPGA chip from Xilinx Inc., XC3S500E-4FG320C. The collected data are first stored in nonvolatile flash on this fuse in-orbit and imported into a USB disk after down-falling. The main hardware and software design of each module are introduced in detail. Experiment results are shown in the final chapter.

To maintain the vehicle air conditioner efficiently, a fault diagnosis system based on fuzzy theory is prospected in this paper. A fault diagnosis method based on fuzzy theory was given. And according to the method, a fault diagnosis program was written with labview. Experiments proved that the fault diagnosis program was stable and functional. The accuracy of this fault diagnosis system is more than 80%. The system can be used to diagnosed the malfunction of vehicle air conditioner efficiently and discover the potential fault in time, helping to eliminate hidden dangers.

In order to solve the problem which is very common when we use a solar water heater for a shower but the hot water can not come immediately because of the cooled water remained in the pipeline, a no-pump cycling water-saving equipment is designed based on a pressure-regulated suction device, temperature acquisition control circuit and a water-saving box. The kinematics and mechanics parameters are confirmed on the result of calculation and software simulation, and are tested by doing physical experiment. It can make it come true to economize the water and energy for solar power heater.

Fire is an extremely complex phenomenon with combustion, flow dynamics, radiation, and chemical reaction and so on. At present, there are two field models often used in compartment fires, which are Large Eddy Simulation (LES) models and Reynolds-Averaged N-S (RANS) models. In this page, three cases of the compartment fires are simulated with both of the two field models. By comparing the temperature of different models to the available experimental data, LES apply to the big space compartment fires and RANS work for the tunnel fires. Both of the models can be used in room fires, but the result is not very well. In the future, there is more work to do on researching the field model in compartment fires.

With the development of new energy vehicle, the current air conditioner technology has been unable to meet the requirement of future automobile. In this paper, the characteristics of traditional automobile air conditioner is summarized. And several new air conditioners, adapting to the new energy vehicles are putted forward. Compared with traditional air conditioner, these new air conditioners are more possible to be used in the future vehicles.

The measured Frequency Response Functions (FRFs) often have errors due to the support effects in free-free modal testing. In [1], elimination of support effects from the measured FRFs has been investigated and both stiffness and damping have been considered in support conditions. However, the method is only applicable for single point support occasion while the test structure is usually supported from more than one location in a practical testing. Therefore, this paper further investigates this method to extend its application to multi-points support conditions. Firstly, general formulas of removing the multipoint support effects from the measured FRFs are derived based on the dynamic substructure method. Then a simulated modal test of free-free beam with two points suspension is proposed to verify this method. Finally, the performance of the method is investigated with simulated noisy data. It is shown that the proposed method is effective in removing support stiffness as well as support damping from the measured FRFs as long as the measured data are not heavily contaminated by the noise.

In this paper, flow patterns transition criteria from bubble growth to confined bubbly flow, from isolated/confined bubbly flow to slug flow, and from slug flow to annular flow are numerical analyzed. The prediction of the theoretical model agrees well with experimental data. By carrying out comparative study, it is indicated that there is an apparent postponement of flow patterns transition of flow boiling in mini/micro-channel than that under adiabatic conditions.

This paper introduces a data processing and control module used for a millimeter-wave radiometer. The STM32F103ZET6 is chosen as an embedding control unit for real-time control and data acquisition and processing，and 8-inch touch LCD screen is used for display and input. The data processing and control unit in total-power radiometer with a Dicke-type switch are presented. The hardware structure and software flowchart are designed for this embedding system. The units effectively adjust physical temperature of the radiometer to acquire appropriate output in the radiometer system without inexpensive commercially available parts.

In modal testing, the measured Frequency Response Functions (FRFs) are often inaccurate due to the adverse mechanical effects, such as mass-loading effects of transducers, shaker-structure interaction and the support effects. This paper deals with the elimination of the support effects from measured FRFs using dynamic substructure method. Both stiffness and damping are considered in the support effects. The validity of the method is proved in a simulated modal test. It is shown that with the given support conditions the affected FRFs can be corrected provided that some additional FRFs concerned with the support point are also measured. Finally, performance of this method is assessed with noisy measured data. Simulation shows that 1% white noise is acceptable in the proposed correction method.

The UFD method was used to analyze the flow field in the swirl atomizer whose geometric structure had been designed with ideal theory algorithm. RNG (Renormalization Group) k-turbulent model was applied to the numerical simulation of the flow field, and SIMPLE algorithm was used to solve the finite difference equations. Through the analysis of pressure and velocity fields get by the numerical simulation, we found that the use of CFD method in the swirl atomizer design is beneficial for getting more detailed and accurate flow structure and advantageous to analyze the influence of different nozzle geometry, and then given a reasonable design opinion.

Stability is an important factor to measure the quality of an atomic clock. The random factor that affects atomic clock includes five kinds of noise. The random noise can be expressed by spectral density function. In a certain smooth time, only one or two types of noise can influence the atomic clock’s stability. Through the relationship between spectral density function and atomic clock stability analysis variance, such as Allan variance, it’s possible to distinguish the kind of noise on different smooth time. When lacking of data, there is a way that can increase the amount of data by mapping extensions, and it can also improve the degree of confidence in the larger smooth time.

Experiments of five fire extinguishing agents on the fires of wood stack and oil were conducted in ISO9705 room. It focused on comparing the extinguishing abilities of the five fire extinguishing agents on Class A fire represented by wood stack fire. It is can be concluded that FM200 had the best extinguishing performance for wood stack fire, and it could prevent wood stack reburning; while IG541 and hot aerosol extinguisher do worst on preventing the wood stack fire reburning. In addition, the effects of extinguishers on heat release rate were compared.

Fire models using Computational Fluid Dynamics (CFD) are now popular design or evaluation tools as the computer’s development sharply. By those tools the thermal fire environment can be predicted in a ‘microscopic’ picture with air flow pattern, pressure and temperature contours. However, most of the fire models are only validated by some experiments not specially designed for such purpose, especially for large rooms. In this paper, an existing fire test was used to justify a fire model - FDS4.07 on predicting fires in large room. Smoke layer height and air temperatures inside the room were taken as the parameters. Functional analysis was applied to justify the predictions by the CFD model.

Based on the study of the residential status in the Three Gorges, the architectural features in the Three Gorges are summed up and its values are explored. The study suggests that the architectural art of residences in the Three Gorges should be protected and inherited to provide references to the conservation of the traditional residences in the Three Gorges region and to offer basis for the new architectural designs in the Three Gorges region.

Compliant elements play an important role in running and hopping legged robots for improving their speed and energy efficiency. The dynamic model of the compliant legged robot was developed by taking into account the slipping, vibration and distributed compliance of the legs. The parameter variations of the system after impacts were researched for different dropping height and angles by numerical method. Meanwhile, the effectiveness of the model was verified through explicit dynamics analysis software. All these results will provide a theoretical guide for the energy efficiency analysis and mechanical design of the compliant legged robots.

Compliant actuators are widely used in industrial robots due to the fact that the compliant elements have the capacity to absorb excessive collision force and guarantee the robot safety. Moreover, the compliant elements can be also employed as force/torque sensors in the control loops. Therefore, the research on the compliant actuators is of importance in the theory and application sides. Specifically, it is required that the robot systems should have a low stiffness when the subjected collision force is greater than the prescribed injury tolerance. But, in the normal status, the systems maintain the required capability. In this paper, the system stiffness of a compliant actuator is defined as a mechanical impedance (the ratio between output force and output shaft angle). A cascade controller is well designed by following the results on analyzing the characteristic of compliant actuator impedance stability and collision. At the end, simulation results show the effectiveness of the analytic results and designed controller.

Compliant mechanism is a kind of new type mechanism and its analysis is very complex because flexible links often under large deflections which introduce geometry nonlinearities. A new model (2R PRBM) can simulate accurately both the deflection path and angle of the flexible link. A new dynamic model of compliant mechanism is developed using the 2R PRBM. The dynamic equation of planar compliant mechanism is derived. The dynamic analysis on the natural frequency of compliant mechanism is obtained in the example of a planar compliant parallel-guiding mechanism. The numerical results show the advantage of the proposed method for the dynamic analysis of compliant mechanisms.

Compliant mechanisms gain at least some of their mobility from the deflection of flexible members rather than from movable joints only. Dynamic effects are very important to improving the design of compliant mechanisms. An investigation on the dynamics and synthesis of the compliant mechanisms is presented. The dynamic model of compliant mechanisms is developed at first. The natural frequency and sensitivity are then studied based on the dynamic model. Finally, optimal design of compliant mechanism is investigated. The experimental study of natural frequency is performed. The comparison between the experiment results and the theoretical results verifies the validity of the experiment system and theoretical model.

For the large computation workload of the adaptive filter algorithm and the low filtering speed of the adaptive filter model based on wavelet transform, a wavelet-based neural network adaptive filter model is constructed in this paper. As the neural network has the capacity of distributed storage and fast self-evolution, Hopfield neural network is used to implement adaptive filtering algorithm LMS, so as to increase the computing speed. The model applied to sEMG signal denoising can achieve a better filtering effect.

To solve the problem of real-time, quantification monitor on the restoration of motor function in hemiplegia after stroke, this paper proposed motor-function evaluation content for 5-DOF upper-limb rehabilitation robot based on traditional motor-function evaluation method, and then it constituted judgment matrix and calculated weights by Analytical Hierarchy Process, finally, established a synthetical evaluation model of motor function for upper-limb rehabilitation robot. This paper is the organic combination of operational research, rehabilitation medicine and robotics. Compare with traditional motor-function evaluation method, the new evaluation method is so simply and flexible that it greatly increases the reliability, validity and feasibility of evaluation, which has changed traditional evaluation methods into mathematical process. It is the new orientation in motor-function evaluation.

Based on the establishment of a two-dimensional model, a numerical simulation was conducted in this paper to study the flow boiling and heat transfer characteristics of ethanol in a corrugated mini-channel. User defined functions were employed to describe the key processes of heat and mass exchange at the phase interface. Bubble growth profile was monitored over time and its influence on system pressure drop and heat transfer coefficient was also analyzed. The simulation result shows that the nucleation sites tend to distribute near the internal peaks of the heating wall due to the enhanced local turbulence. The system pressure drop increases over the heating time and fluctuates within a certain range. The heat transfer coefficient decreases with increasing quality, and this trend is consistent with the result of similar experimental studies.

In this paper, the boiling phenomena of steam boiler under atmospheric pressure are simulated by using the UDF program of CFD software. Characteristics including pressure, temperature and vapor fraction respectively for bubble, slug and annular flow regimes are extracted as the input characteristic vectors of the BP neural network and Elman neural network for the purpose of identifying the boiling two-phase (vapor/liquid) flow regimes within wall tubes. It reveals that the rate of recognition accuracy of flow regimes with BP neural network is up to 95.24%, as well as 100% with Elman neural network within the groups taken into consider. By analyzing relations between flow regimes, wall temperature and wall heat transfer coefficient, it is found that changes in flow regimes will cause drastic variation in heat transfer coefficient of the wall surface, and the coefficient reduces rapidly as the wall temperature increases and eventually converge to a minimum. It is a very effective method of using numerical simulation to extract the signal under poor experimental conditions, and is good reference for the further research.

Unascertained clustering is an unsupervised clustering based on unascertained set. It is a method to make soft division of objects which is more scientific and realistic than the general one. According to the basic idea of unascertained average clustering, we write a specific procedure to achieve calculation by the MATLAB technology and then we verify the feasibility and effectiveness of the written procedures as well as the practical value and feasibility of calculation through case study.