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In this paper, nanosteps were fabricated by a new method. This method used the energy of focus imaging of focused ion beam to peel the material surface for fabricating the nanosteps. By changing the number of focus imaging can get different deepness nanosingle-steps. Changing the magnification, the second-step can be fabricated on nanosingle-step. An atomic force microscopy was used to measure the 3D morphology of nanosteps. When the magnification was 25000, the deepness of nanosingle-step was 65.34±3.00 nm and the deepness of the first step of nanodual-step was 56.03 nm. When the magnification was 50000, the deepness of nanosingle-step was 142.28±3.54 nm and the deepness of the second step of nanodual-step was 178.68nm. This means that the redeposition made the deepness of the first step become bigger, that of the second step becomes smaller. Based on comparison and analysis, the relation of the depth, the magnification and the number of the focus imaging were obtained.

A “laminar + transition criteria” model utilizingReθ/MeandReCFcriteria in conjunction with an intermittency functionΓis developed in this paper. With pretreated computational grid and total enthalpyh0=(h0,∞)maxcriteria the boundary layer edge and crossflow velocity can be obtained by using parallel methodology. Validation is accomplished via HIFiRE-5 and a blunt cone with small angle of attack. Results show that computedReθ/MeandReCFdistributions are similar to theN-factor for streamwise instability and crossflow instability from linear PSE methods. The shape and trend of transition regions predicted by the “laminar + transition criteria” model in HIFiRE-5 and blunt cone are in good agreement with the experiment and DNS. However, for the transition induced by inflection point on streamwise velocity profiles, using criteria related to boundary layer thickness is inappropriate and can predict transition onset prematurely.

According to the current situation of agricultural and the theory of industrial design, the views using the method of industrial design concept, technology, to promote the development of agricultural machinery product innovation, transformation were proposed. The agricultural machinery product development strategy and the effective ways based on industrial design innovation technology were studied. It has a guiding role in development of agricultural products with innovative and development of agricultural machinery manufacturing.

In order to improve the accuracy and reliability of multi-source heterogeneous data in the collection process for environment monitoring, according to the analysis of the limitations, the existing methods and the features of data collected, a new kind of data fusion approach based on extended Dempster-Shafer theory is proposed. The mathematical description of extended Dempster-Shafer theory based on the data fusion is defined and the corresponding model is developed in which the data fusion method and the implementation of the algorithm are discussed. Finally, the proposed approach is applied to a computing system. The study of this approach can supply scientific accordance for comprehensive monitoring of environment.

In this paper, we present a coordinate rotation digital computer (CORDIC) based fast algorithm for power of two point DCT. The proposed algorithm has some distinguish advantages, such as regular data flow like the Cooley-Tukey FFT, identical post-scaling factor, and the rotation angles of the CORDICs in DCT are arithmetic sequence. By using the sum formula and double angle formula, we dramatically reduce the CORDIC types in the proposed algorithm. For the purpose of gain fast speed, we use Carry Save Adder (CSA) as the basic cell of each part and Carry Look-ahead Adder (CLA) to produce the outputs in the final level. Compared with other known architectures, the proposed 2-point DCT architecture has lower hardware complexity, higher throughput and better synchronization

In order to enhance the organization and management efficiency of multi-source heterogeneous data in the collection process for urban ambient air quality monitoring, according to the analysis of the limitations, the existing methods and the features of data collected, a new kind of multi-sensor and multi-level information fusion approach based on vague sets is proposed. The approach takes full advantage of the redundancy and complementarities from inter-level information to achieve the purpose of information integration. The mathematical description of vague sets based on the multi-sensor information fusion is defined and the corresponding model is developed in which the data organization and the monitoring method and the implementation of the hierarchical algorithm are discussed. Finally, the proposed approach is applied to a computing system of the ambient air quality monitoring. The study of this approach can supply scientific accordance for comprehensive monitoring of urban ambient air quality.

In this paper, a seventh-order elliptic low-pass active-RC filter with three finite transmission zeros is designed for the baseband filter of a 433MHz wireless communication terminal. While designing, the canonical signal flow graph (SFG) method is applied based on component-level simulation of LC ladder prototype circuit. The simulation and measurement results show that the filter satisfied the design specifications.

The partial discharge (PD) detection systems are often vulnerable to strong external interferences, and sometimes the PD signals are submerged in noises (white noise for example) completely. So the signals acquired must be preprocessed to obtain the reliable PD information. While there are many methods for white noise denoising, mostly are not very suitable for partial discharge. The wavelet transform (WT) coefficient of PD and white noises have different spread characteristics in different WT scales. Based on the Information Theory, The Minimum Information Description Length (MDL) criterion is a optimization strategy, a small amount of signal parameter is requried to the PD signals representation, the paper proposes a wavelet spatial correlation algorithm to partial discharge denoising based on MDL criterion: optimal wavelet function is selected based on MDL, then have the white noise reduced in WT, the algorithm has wonderful virtues such as free from any parameters estimation about noise, free from presetting threshhold and threshold chooseing behavior, so the algorithm is highly adaptive. Large amount of experimental results illustrate that the method presented in this paper are efficient and feasible and outperforms other general method of PD noise reduction.

Hypersonic flow of Mach number 8 past a 25°-50° double cone geometry is numerically simulated at ReD=4.8E5. Complicated flow structures, including Type V shock-shock interaction, shock-boundary layer interaction, separation and reattachment at the corner are presented and discussed. The surface pressure and heat transfer rate distributions are also calculated and compared with the experimental data. Results show that both the 2nd order MUSCL and 5th order WENO could accurately reproduce the shock structures, while the higher order scheme could predict a more accurate size of separation zone. Generally, the size of the separation zone is underestimated with an overvalued pressure distribution after reattachment employing the full turbulent models. On the other hand, transition induced by the reattachment shock has been calculated using transition model and the results of pressure peak and the size of separation zone show good agreement with the experimental measurements.