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The heat of the positioning platform is mainly caused by conduction of each functional unit, when it affected by the influence of internal and external heat source at work, the temperature of units would change, and the condition would make the platform component stiffness change, then lead to positioning platform dynamic characteristics change. In this paper, the finite method analysis platform dynamic connection stiffness with the regularity of temperature change, and by using the grey correlation method to optimize the platform stiffness influence of the four largest temperature sampling point, through the neural network modeling method to establish high precision positioning platform stiffness model, provide theory for the research on platform of dynamic characteristics of the model.

Rotation machine plays an important role in the production of electric power, chemical industry etc... In the methods of fault diagnosis, the selection of the Pc and Pm of common genetic algorithm will influence its convergence and is easy to be trapped into the local optimum to propose an adaptive genetic algorithm of the fault diagnosis; and in the implementation of system function, it takes the S3C2410 chip as the core of the microprocessor and uses the embedded Linux as the operating system as the software development platform. In this paper ,it introduces the design of the various parts of the system hardware in details, achieves the Boot Loader through combination of the hardware platform and successfully transplants the Linux operating system and builds a root file system, with the combination of the Linux operating system platform, it achieves the LCD frame buffer display device frame buffer, touchscreen A/D converter and development of Ethernet driver program, and the develops the data acquisition, wavelet packet analysis and Ethernet driver program etc. based on the system functions.

A new composite drive supercharger based on crank rod in series with symmetrical hinge is introduced. This device utilizes the principle of hinge rod’s force amplification and combines with a two-stage double-acting hydraulic system, it achieves a good booster effect as a result. The two opposed piston-cylinders are excellent for the supplying of the system’s sustainable pressure, it is applied to high power output and green manufacturing. This article carries out a detailed analysis on the operating principle of the system, and the output flow and pressure’s formulas of the low-pressure high flow and high-pressure low flow were given.

The method of cyclic redundancy check (CRC) was been used in the process of RFID communication adopts to ensure that the data was transfer correctly. The principle of CRC was been introduced. The design method about 16-bit CRC code was been gotten through the hardware circuit and hardware description language. And it was compatible with the serial and parallel two kinds of data streams. At the same time it was been verified correctly in RFID communication system. And the results are verified in the specified clock frequency in xc2vp4-6fg256 device in FPGA Xilinx kit using VI-IDL in RTL level. It with strong portability could extend to all CRC system.

Mesophase microbeads were prepared by thermal condensation in the presence of heterogeneous and homogeneous systems. Morphologies and sizes of mesophase microbeads are characterized by scanning electronic microcopy (SEM), polarized light optical microphotography (PLOM) and laser particle size analyzer. SEM and PLOM results exhibit that mesophase microbeads have a narrow size distribution and many large particle in heterogeneous system. In homogeneous system, there are a great deal of smaller mesophase microbeads and a very little of larger mesophase microbeads. The laser particle size analysis results show that size distribution of mesophase microbeads in heterogeneous system is quite different from that in homogeneous system. There are multi-peaks on volume distribution curve in heterogeneous system. Larger mesophase microbeads are mainly in tens micron peak of size distribution curve. In homogeneous system, particle size of mesophase microbeads has a wide distribution and only single peak on size distribution curve. Moreover, sulfur concentration in reaction system makes the size of mesophase microbeads increase and the size distribution curve move to larger particle diameter. But sulfur concentration can not affect the curve pattern of size distribution.

Volatiles of maca in vitro could be captured by way of dynamic head-space adsorption. Both maca root and leaf volatile compounds were different from essential oil or other extracts. In the root volatiles, isothiocyanates were in the highest content (27.26%), especially 4-ethylphenyl isothiocyanate over 20%. Together with chloro-compounds (near 20%) and tetrahydro-3-methylfuran (14%), the three types of chemicals were probably important factors of maca’s special odor like other vegetables of Brassicaceae. And in the leaf volatiles, the highest contents (about 30%) were found in acid and anhydride. Compared to maca essential oil, ester (

Traditional cooling methods for electronic chips cannot fully meet the increasing cooling requirement of chips with high heat flux at present, so finding high-efficiency and low-cost cooling functional materials, and cooling methods with high efficiency has been a hot spot to explore. In this article, using Fluent 6, we construct a grooved channel physical model and analyze cooling effects of ethylene glycol/water ice slurry as a functional material on the chips under conditions that baffle lengths are 60mm, 80mm and 90mm, the mass flow rates are 0.4kg/s, 0.3kg/s and 0.2kg/s, and the ice fractions are 15%, 20%, 25% respectively. The results show that the chip cooling rate is increasing effectively and the temperature uniformity is better as well as the utilization rate of the latent heat is increasing as the length of baffles, the mass flow rate and the ice fraction are increasing, but the pressure loss resulted from the local effects of the inlet and corners cannot be ignored. Considering the cooling effect and the uniformity of temperature field, the length of baffles should be 83%-93% of length of flow path. In practical projects, the temperature difference between inlet and outlet should be reduced and the diameter of pipes should be decreased in order to take full advantage of the huge latent heat of the ice slurry while the ice is completely melted. Therefore, ice slurry as a functional material has a great potential to cool high integrated electronic chips.

Phyllanthus emblica L. was abundant with Vc, SOD and other nutrients. In order to find a rapid and low loss way for its solid product, spray-drying was tested on its juice. According to orthogonal experiment, the best drying condition was selected as the concentration of 0.22g/mL, input temperature of 120°C and air velocity of 0.65m3/min. With the optimal drying, it was yielded the highest amount of powder at 57.4% and 52.6% of Vc in raw juice was maintained in the dried product. The final powder was still full of SOD and its inhibition rate to autoxidation velocity of pyrogallol was 29.6%. Color, particle size, flavor, taste and resolubility were well available to solid beverage requirment. It was indicated that the technique was efficient for the drying of P. emblica L. and the dried product was anti-oxidative to some extent.

In Procession of fast Urbanism, At the background of striations of natural condition and land supply shortage, It is the key question which urban size will upgrade and urban structure will change, that Optimizes spatial layout and creates urban features. This paper with case of Yan’an analyses the problem that exists in metropolis spatial layout; then discusses urban planning measures that optimize urban structure to hold compact urban morphology. Finally it sketch out the highlights city "landscape pattern" of the urban space structure optimization strategy.

For the improvement of processing and the increase of refined products of Chinese insect wax, it was carried out on the raw wax for its refining in the pilot plants. After the treatment, it was raised the melting point and reduced the acid value, iodine value, saponification value and insoluble substances of benzene significantly. The quality of final products was accord to the industrial top-grade requirement. The yield of refined wax was ranging from 72.76% to 74.30% and the whiteness was 51.8% to 56.3%. It was not observed any chemical changes of the wax during the processing.

Thermal properties of 5 natural resin and wax samples (shellac, rosin, shellac wax, beeswax, Chinese insect wax) were examined by differential scanning calorimetry (DSC). The DSC melting and crystallization curves of the samples were presented in this paper. Three DSC parameters, To, Tf and ΔT (difference between To and Tf), were selected from each curve. Evaluation results of the parameters showed that they were statistically significant with individual excellent reproducibility. Information was provided by evaluation of changes among thermal absorption or release peaks of the curves in differentiating the five resins and waxes. It was demonstrated in this paper that DSC is rapid, convenient, reliable and accurate to qualitatively identify the resins and waxes mentioned above.

For the wide application of insect wax, it was studied on its thermal properties under different conditions in which the wax was stored at cold, dark, indoor and sunshine environment. Differential scanning calorimetry (DSC) was selected to achieve thermal parameters and reveal the influence of temperature on the stability of the wax. The result showed that within 20 months of natural storage, it was significant influence on the melting enthalpy of Hunan insect wax, the melting point of Sichuan insect wax and the melting peak of Sichuan insect wax with the Sig values were 0.013, 0.009 and 0.000. And the quality of wax was characterized by IR, XRD and physical-chemical indexes. The results showed that within 20 months, it was slightly changed in the crystallinity and chemical constituents. Therefore, the wax with good stability can be used for medicine, food, functional materials and other industrial purposes safely.

To enhance the product quality and production efficiency, we studied the kinetics of the microwave - vacuum drying of bleached shellac and optimized its technological process. Through the test, the drying curve, drying rate curve and drying constant of the bleached shellacs under different pressure were obtained and through the drying curve fitting, the drying model was obtained. And through the optimization test, the optimal conditions for the microwave - vacuum drying of bleached shellac were obtained, that is, pressure of 3000Pa, microwave power of 700W and drying time of 25min, then the products of color index of 0.9, water content of 0.0296 kg water / kg dry materials were obtained.