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Aiming at the radar vertical detection coverage limitation given by manufacturing factories, this paper put forwards a new characterization method of radar’s air surveillance coverage: it is the projection distance of furthest detection point for different RCS targets at different altitudes, which can directly show radar’s quick response to the attack action launched by fighter. Then this paper gives the calculating method of coverage characterization method, and calculates radar detection coverage of typical medium-low altitude search. The result shows that the detection ability to penetration fighter is weak for high altitude and below 300m altitude, especially for the high altitude penetration stealth fighter.

A frequency measurement method based on signal delay detection is presented. The method adopts multi-path same delay line to generate multi-path delayed signal whose period is almost the same with that of the reference signal, the average delay time of two adjacent signals that are detected is selected as the interval between the reference signal's rising edge and gate's opening and closing time to calculate the frequency of the measured signal. Error analysis and measurement uncertainty evaluation show that the precision of measurement of the method is determined by the delay time. Experimental data verify that the method could ensure testing speed while effectively reduce the error of ± 1 count.

Combined with the Map/Reduce programming model, the Hadoop distributed file system, Lucene inverted file indexing technology and ICTCLAS Chinese word segmentation technology, we designed and implemented a distributed search engine system based on Hadoop. By testing of the system in the four-node Hadoop cluster environment, experimental results show that Hadoop platform can be used in search engines to improve system performance, reliability and scalability.

Focused on static high-definition sequence images captured on the highway bayonet, this paper proposes a new approach for vehicle detection and shadow elimination based on average background modeling, which uses average background model and background subtraction to locate vehicle roughly, eliminates shadow of the vehicle using canny edge detection with dynamic histogram threshold determined by the histogram of the image. Experiments show that this method can locate the position of vehicle quickly and accurately.

An Approach that measuring static radial and axial runouts around rotational centre of spindle for cylindrical mills on milling machine was presented, its possible errors coming from imprecise location of gauge were theoretically analyzed. Milling force measuring experiments with variable feeds and cutting depths in low spindle speed was done to estimate the static runouts, these estimated values then were used to test the precision of measured values with this approach. Both results of theoretical analysis and experimental test showed that the relative errors of this measuring approach were small. This approach is to measure the runouts of installed mills, and its measured value is rather precise, its operation is simple, and it needs no special gauge. This approach can be used in study on force of cylindrical mills.

A novel edge detection method based on anisotropic mathematical morphology and scale multiplication in nonsubsampled contourlet transform (NSCT) domain is proposed to obtain a superior and robust performance under heavy noise. One preliminary result is obtained using anisotropic morphological gradient of the low-frequency component, yielding a single-pixel response with few pseudo edges. Due to the great ability of NSCT to localize distributed discontinuities such as edges, scale multiplication results of high-frequency components can get rid of a large amount of noise and produce well-localized edge candidates. The final result is a fusion of the detection results of low-frequency component and high-frequency components. Detailed experiments compared with other state-of-the-art methods demonstrate that the proposed method has a superior performance of edge detection and is quite robust even under heavy noise.

Post-disaster transition is necessary in disaster relief. Care, security and sustainable development are the basic principles of the temporary resettlement area planning. The planning has particularity in the use of function, safety precautions, the project cost, psychological relief and so on. Architectural design also has special technical requirements in the use of the function and cost control and sustainable development.

This paper presents a pointer positioning method based on Hough transform, which turns an arc scale to a transverse rectangular scales, scans the region from bottom to top line by line, determines smaller rectangular area containing pointer only, uses Hough transform in linear theory to detect the pointer position in the region. Experiments show that this method can locate the pointer position quickly and efficiently in analog measuring instruments.

For the beam with certain degree, it was difficult to reflect by displacement modal and natural frequency. The present paper first derived nodal strain modal through its corresponding displacement modal, and then evaluates the strain modal, both prior and post damage, the difference between the strain mode was used as a criterion to assess the damage experienced, based on a simple beam element damage localization method. The formulated method had been demonstrated through ANSYS numerical modeling to be capable of effectively identifying the damage.

A kind of multifunctional audio digital watermark algorithm was put forward according to the copyright protection of audio problems. The audio signal is layered three by wavelet packet decomposition and robust watermark is embedded in the low frequency part, fragile watermark is embedded in the intermediate frequency part. The experimental results show that, the algorithm has no sound very good, excellent robustness and fragility. In the actual use of the process, which not only guarantees the safety of audio information effectively , but also guarantees good audio information fidelity.

Time-domain expressions of nominal component and eccentric component that composing horizontal peripheral milling force are derived from geometry of down milling, they are periodic functions with fundamental frequencies same as tooth-frequency and spindle-frequency respectively. By expanding these two time-domain expressions with Taylor series, the frequency-domain description of periheral milling force is obtained. Further mathematical reasoning is exerted on this frequency-domain description, and it proved that as for four-tooth end mills, even-order harmonics of eccentric milling force do not exist, and the amplitude of spindle-frequency component be linear with eccentric distance, but irrelevant with eccentric angle. Above research results imply that the tooth-frequency component of four-tooth end mills is irrelevant with eccentricity, and that eccentric distance can be estimated with amplitudes of tooth-frequency and spindle-frequency components. Results of milling experiment imply that this eccentric-distance estimating method be effective. Spectral characteristics of eccentric milling force for four-tooth end mills are revealed with theory deduction, and the estimation algorithm for eccentric distance with simple calculation is present. Study conclusions can be used in eccentric-geometry estimating and in milling-force modeling.

Based on the characteristics of high power diesel engines’ thermal balance analysis, a diesel engines’ thermal balance test and analysis system is developed through dealing a large number of test data. This system can real time monitor the temperature, pressure and flow rate of the components in cooling circuit, fuel circuit and gas circuit, can continuously record and store the state parameters, can realize theory computation, statistical analysis, query, and print data report. Also the system can realize remote operation. This system has already been operated in several enterprises. Results show that the system can estimate diesel engines’ thermal balance effectively. According to the analysis results, diesel engines’ designers can estimate the components that bearing excessively high thermal load and can solve the thermal balance problem of high power engines.

The damage identification research based on strain mode was discussed in this paper, and based on MATLAB, the models on the severy conditions of preset damaged was compared also. The results show that this method is more rapid, and the parameters impact of the strain mode is more intuitive than other finite element analysis software. The damage location and the extent of injury of simply beam can accurately determined by strain mode shapes. The conclusion is theoretical academic significance value of assess in service bridge structure examination.

In this paper,through combination research methods of Gambit modeling and Fuent solving,we has received the curve of nozzle pressure vector, vector of velocity and velocity change curve,Which has provided the effective analysis method for eliminating descaling ineffective and the steel plate surface defect. Minimum field pressure Locate in the middle of the nozzle and hit place,Maximum field pressure Locate in close to the body surface part;220mm is the maximum target distance;According to the formula-type fluid calculate,it can concluded that simulatere result is credible.

In this paper,SWRH82B steel as the object of study,analysis of several typical drawing fracture tpyes to explore the reasons for fracture by SEM testing.The results show that:the type of slope-type fracture mainly due to cracks defects generated in surface of the wire rod;the Pen-shaped type fracture due to central segregation in the continuous casting process;whole flat brittle fracture mainly due to a serious slag in the continuous casting process.

Jinoping No.1 is a dominant reservoir cascade hydropower station which locates at the downstream of Yalong river. The underground powerhouse locates at the right bank of the dam, lithology is marble that belongs to the second member of Zagunao group. It is constructed at region with very complicated geological conditions and high geo-stress. Concrete cracking, spalling and steel buckling and bending occurred at the downstream crown after supporting. This paper analysed the causes of deformation and failure through geological analysis and numerical simulation, and concluded that deformation and failure mainly occurred at the region where the quality of surrounding rock belongs to Ⅲ1 and had nothing to do with the unstable block cut by cracks; stress field of surrounding rock varied continueously with the proceeding of successive excavation of underground powerhouse, so the compressive stress and shear stress concentration occurred which caused the compression and shear failure of downstream crown and made it bending to the free face. It is significant to the further enforcement of this project and to the research on other similar underground caverns theoretically and practically.

Through the orthogonal test in which stainless steel 316 was milled with high speed by solid cemented carbide end cutter, the milling force was measured. By multiple linear regression method, the prediction formula of the milling forces of stainless steel 316 was found. In addition, this study validates to significant degree of the formula meeting the actual condition, which can provide a reference to better selection of cutting parameter in advance and the design of high-speed milling cutter.