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Wind turbine gearbox is the key component. Because of alternating loads caused by gear engagement, variations of wind speed and fluctuation of load, it is prone to get fatigue damage, which lead to the high failure rate and low life. In this paper, obtaining the stress time histories through multi-body dynamics simulation, then base on the simulation data, statistical processing load time histories by used rain flow counting method, the last is that estimating fatigue life of components, combined with P-S-N curves of parts material and linear cumulative damage law. The fatigue life prediction of each component in gearbox would be implemented by matlab programming. Through the fatigue analysis of a megawatt-class wind turbine gearbox transmission chain, the design was verified feasibility, but not economic, and it show that this method has certain reference value and potential for improvement.

In this paper, the seismic behavior of partially encased concrete columns and steel beam connection are studied, which contains 4 different structures of beam-column joints. By applying a low cycle loading, the failure modes and the strain distribution of each connected component plate domain were studied. The effect of the end plate thickness, stiffened plate, and back plate on the node bearing capacity, stiffness and ductility was analyzed. The bearing capacity of the specimen is improved with the end plate thickness increases, and a lot increased with setting the back plate.

The primary mission of this design is the air conditioning design of a hotel in Guangzhou city. The calculation of cooling load & heat load, division of the air conditioning system and the determination of the scheme, the design of the duct and water system, and the design of the smoke prevention and extraction system are all included. According to the related standard and considering the energy saving and comfort requirements, the air conditioning system are determined through the economic and technological comparison. Primary return air system is used for open office area and dining hall; fan-coil units with fresh air system is adopted for the guest rooms of the hotel; and the VRV system is adopted for the large conference room. The new air in restaurant rooms and the large conference room is handled by full-heat type fresh air exchanger; new air in guest room is handled by air conditioning units.

After the Japan nuclear power crisis in 2011, main nuclear power countries and international organizations reactions to nuclear emergency and security problem had become a hot topic. The global concern on power emergency problem after the Japan Fukushima nuclear crisis was reviewed comprehensively. The International Atomic Energy Agency (IAEA) investigation, the U. S. NRC Security Check, EU stress test, and France ASN complementary safety assessment results were stated in detail. As an important source of power, China’s altitude toward the sustainable nuclear power development and safety was also surveyed. The main nuclear power countries all claimed their position to insist on the development of nuclear power while taking lessons from Japan Fukushima nuclear crisis. Finally some comments and suggestions to improve China’s power industry emergency response and drills system to support the sustainable development of nuclear energy were proposed.

In this paper, NiTi-Ti2Ni-TiC composite powders were first prepared by in-situ reaction in molten salt and then sintered by a cubic high pressure apparatus under 8 GPa to produce bulk composite material at a short time. It was found that the composite was composed of TiC particles embedded in NiTi-Ti2Ni matrix, in which the Ti2Ni encapsulated TiC particles. The martensitic transformation of the NiTi matrix was evidenced by differential scanning calorimetry analysis. The research on the sintering mechanism shows that there may be a reaction like TiC +Ti2Ni 􀃆 Ti2C + NiTi existing under the pressure up to 8 GPa

Characteristic parameters of joint surfaces are needed in kinetic modeling of the motor frame while analyzing its vibration behavior. In this paper, research on tangential dynamic characteristics of mechanical joint surfaces in the motor frame is executed. In order to get the tangential contact stiffness and contact damping of interfaces in the motor frame under different joint conditions, an experimental method is proposed according to the structure feature and running condition of motors. A test platform is specially designed and set up. The kinetic model of test specimens (including the test joint surfaces) is derived. The experimental system is developed. The tangential dynamic contact stiffness and contact damping are identified by the experimental system. The variation rules of the contact stiffness and contact damping with changing of pre-load, exciting frequency and surface roughness are got and summarized. And the rules are consistent with the physical essence of joint surfaces.

Water quality monitoring plays an important role in contamination control and environment protection. This paper describes an on-line multiparametric water quality monitoring system based on visible spectrophotometry, which combines embedded technology with GPRS telecommunication technology. This system can realize online wireless monitoring to concentrations of chromium (Cr), plumbum (Pb), A surfactant (AS), chemical oxygen demand (COD), ammonia nitrogen (AN), total phosphorus (TP) and total phenol (TPh) in real time. The mechanical structure, hardware circuit and software design of the system are completed. The absorption spectrums of pure water and MB-SDS complex have been measured. Preliminary experiments using a model machine show that each mechanism of the system runs well. Moreover, the monitor possesses many advantages, such as high degree of automation, high reliability, high efficiency, compact structure, small size, and so on.

According to the reasons and features of car accidents happening in vehicles’ side areas, this paper designed and developed a kind of automotive lateral anti-collision warning system by frequency modulation continuous wave, based on the research on 24GHz linear frequency modulation continuous wave radar-probing system. The system designed in this paper will forecast the potential danger to drivers and avoid the accidents. The hardware structures, algorithm, program flows and working patterns of the warning system were introduced. Furthermore, pointing to the problem of false alarms, a kind of filtering method was presented creatively. This method improved the reliability of the warning system and the accuracy of the forecast. It filtered the disturbance coming from the side of the vehicles, and solved the difficult problem that prevented the millimeter-wave radar from being applied in automotive lateral anti-collision warning system. Finally, the experiment was designed and carried out. The result verified the rationality of the solution and the practicality of the system’s function.

In this document, we describe the characteristics of UML and modeling process in brief, building the use case model, static model and dynamic model based in UML, then accomplish the requirements analysis and system design of the Production and Dispatching System of Provincial Measurement Center.

The MoS2/TiN composite coating was prepared on Ti-6Al-4V by the combination of plasma diffusion and magnetron sputtering techniques. The microstructure and phase constituents of the composite coating were analyzed by scanning electron microscopy(SEM) and X-ray diffraction(XRD). The abrasion resistance of the composite coating was examined on MM-200 abrasion tester. The results revealed that the composite coating consisted of MoS2, Mo, TiN and Ti phases, and its abrasion resistance was excellent under dry friction and absolute sliding.