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On the basis of a brief introduction of how the automatic gain control (AGC) of the digital reconnaissance receiver works,this article proposed a digital AGC design method based on the digital processor parts, which provide a guarantee for the digital reconnaissance receiver to work in the complex external electromagnetic signal environment. The engineering implementation of AGC is introduced with specific projects. Both simulation and engineering practice verify the feasibility of this program.

This paper elaborate the structure of parison wall thickness control system; choice hardware of the control system; study on the determination of the thickness control method and control points of parison wall; research on the formation of the parison wall thickness curve; summed up the development process of extruding plastic machine heating method on the basis of the plastic molding machinery development; analysis the various of heating methods; summed up the advantages and disadvantages of various heating methods; explore their advantages and disadvantages for providing reference.

Most of hollow plastic products and plastic containers are blow molded In life and chemical transport industry, Extrusion system referred to as "heart" in a hollow blow molding equipment. Hollow extrusion blow molding processing of convenience, plastic products are widely used, and people's emphasis on resource utilization puts forward higher requirements for extrusion blow molding, In view of the hollow blow molding equipment large output, high efficiency and low energy consumption requirements, the development of extrusion equipment for the design and optimization.

With good repeatability and simple structure, transmission line pulse (TLP) has been used in immunity test of integrated circuit and printed circuit board. A TLP generator is first manufactured and its output waveform is presented. By using wavelet transform, the waveform is denoised and discriminated to components inherent to system function and parasitic parameters. Frequency spectrum changed with time is also obtained by continuous wavelet transform of complex morlet. Decomposed damping oscillation component and high frequency component in instant frequency spectrum show influence of inductance in circuit on the waveform. Improvement of rising time and overshoot is achieved by change of probe connection with shorter grounding line.

This paper discusses effect of transmission tower on electric field under overhead lines. Charge simulation method is used. Transmission tower is taken into account by using a simplified frame. Segments of tower frame are represented by finite straight line charges. Overhead lines with conductor sag determined by catenary equation are also represented by finite straight line charges. Calculation results show that transmission tower has shielding effect on closed region and distortion effect nearby tower leg.

Create 3D entity model of the loader’s frame in Solidworks, assemble the frame and then import in ANSYS to get the finite element model of the frame, and use ANSYS to analysis the frame at 5 Static characteristics of different conditions. The analysis indicates that the design scheme of the frame is feasible, but need to increase the stiffness of the structure in some parts.

On the basis of traditional hollow blow molding machine head, this paper researches the accumulating corner style machine head. This kind of machine head employs double layers and double spiral flow channels which solve the intensity problem of the large scale blow molding machine with single spiral flow channel on the fusion seam area. His paper researched the technological parameter and structure size based on the structural style.

The system simulates completely the water polo-game of entity bionic robot-fish, designed and developed based on Microsoft Robotics Studio SDK(MSRS) 1.5, which includes seven modules, such as client strategy, server core control, common interface, environment setting, simulation data display, assistant function, fish robot kinematics modeling and so on. The simulation system simulates the motion of bionic robot fish and the entire process of water-polo-game in real time, and provides simulation testing platform for bionic-robot-fish model optimization, machine fish movement algorithm, and robot fish water-polo-game.

This paper studied influence of three dimension complex ground on electric field under overhead lines. Surface charge method is discussed and planar triangle surface charge elements are used to represent complex ground. Electric field of overhead lines is analyzed by charge simulation method. Finite straight line charges are used to represent conductors. Then electric field of 220kV double circuit overhead lines over a three dimension small hill is calculated and distribution of electric field 1.5m above the ground is analyzed.

Controlled-source electromagnetic (CSEM) is an artificial source electromagnetic sounding method. which developed on the basis of magnetotelluric sounding. For showing the CSEM forward modeling result, numerical simulation method must be adopted. A discontinuous Galerkin finite element method is presented to solve problems based on formulation.

Radiated electromagnetic interference (EMI) is an important criterion for electronic equipment to be met. In the paper, radiated EMI generated by electronic equipment is discussed. Several radiation structures are presented and approximate expressions of maximum radiated electric field are given. In order to reduce radiation of electronic equipment, its important to eliminate unintentional antenna structure and reduce maximum size of aperture and slot on shielding enclosure.

Lately pipe bursts of urban water supply systems all over China could be learned briefly by analysis on news about water pipe bursts in Year 2010. Reasons about pipe bursts, relationships respectively between time, sites, materials, pipe diameters, pipe age and pipe bursts are discussed, and some serious water pipe bursts were introduced. Construction, aging, foundation change, temperature change, exclusive load, overpressure, engineering quality problems were main reasons for pipe bursts of this year.

Hasofer-Lind method was applied to reliability design of cylindrical shell with internal pressure. The respective reliability design thickness of different diameter ratio was obtained in the case and compared with the thickness by the second moment reliability design method. The results showed that the wall thickness of cylindrical shell with internal pressure is the thinnest by using Hasofer-Lind method. And it is closest to the wall thickness of the second moment method in which the performance function was defined as the difference in actual wall thickness and the wall thickness needed for cylindrical shell with internal pressure.

8 pressure vessels of carbon fiber reinforced plastics (CFRP) have been manufactured with in the winding technology of same continuous carbon fiber–-amine system, new same flexible formula and same tension system. And the hydraulic bursting tests with the specimens were done in accordance with GB6058-85. The parameters of fiber strength, winding angle, geometric sizes and burst pressure were obtained by the tests. The theoretical analysis was done by conventional design method and reliability design method. The results show that: the theoretical calculating thickness of CFRP pressure vessel with by same parameters is thicker than practical thickness. This shows the performance of CFRP pressure vessel is related not only with fiber strength but also with material properties of resin matrix, tension and solidifying system of winding process. Because of CFRP (Carbon Fiber Reinforced Plastics) have many advantages which are high specific strength, high specific modulus, ablation resistance and low cost. Although the thing that composite materials have been substitutes for metal shell springs up soon, the application is much wide[1-6].

Tunnel collapse causes serious casualties and economic losses. One typical case analysis of a collapse in deep-buried tunnel based on microseismic monitoring is presented. The results show that the number of microseismic event keeps increasing and the distribution of microseismic events becomes concentrated in space domain gradually during collapse nucleation process. And average distance squared decreases gradually during the imminent period time just before the collapse. The failure evolution mechanism of the collapse is analyzed by moment tensor method. It is noted that the failure mechanism between this kind of collapse and immediate strain-structure rockburst is similar. However, the proportion of shear and mixed fracture for collapse is higher than immediate strain-structure rockburst. It due to the rich structure planes in collapse zone.

For decreasing axial milling force in helical milling and improving machining quality, researches have been carried out on end mills’ geometrical parameters. And experiments have also been designed to analyze the effect of end mill’s axial cutting edge angle on axial milling force. The results indicate that when other mills’ geometrical and process parameters are constant, the generated mean axial milling force is remarkably decreased, following the axial cutting edge angle’s little increase. In addition, as the pitch of helical milling path increases, larger axial cutting edge angle leads to higher relative decrease ratio. And a qualitative analysis is also put up to point out the reason for the phenomena above, that is, part of the low-speed region of axial cutting edge quits milling. These conclusions could supply valuable references to reasonable choice of combinations of mills’ geometrical and process parameters in helical milling.

In order to improve the absolute accuracy of the robot, one new simple and inexpensive, yet accurate robot calibration method is presented. The process assumes the robot can move along a line in the robot’s workspace. The actuators remember the angle information of each joint, when the robot moves along the line. The date that obtained by this method, simplify the process of deducing the kinematic parameters. The paper establishes the evaluation function, which demonstrates the fitness degree of the robot’s position and orientation to the line. In the end, simulation method has been adopted to testify the method, and the method is shown simple and feasible.

In high strength pipeline steel rolling technology, the control of final cooling temperature of different microstructure, different microstructure of pipeline steel tensile strength, yield strength and the effects of different, thus determine its yield ratio differences. The results show that with lath bainite microstructure of the pipeline steel than with acicular ferrite microstructure of the pipeline steel with lower yield ratio, at the same time lath bainite microstructure in small dispersed precipitates in pipeline steel X80 pipeline steel to reduce the yield ratio is beneficial, for high strength pipeline steel production technology to provide the theory basis.

On the elliptic curve cryptosystem proposed a new multi-proxy signature scheme - (t, k, n) threshold blind proxy signature scheme.In new program blind proxy signature and (t,k,n) threshold secret sharing scheme will be combined, and will not over-concentration of the rights of the blind proxy signer .Computation of the program is small, security is high, the achieve efficiency and the utility is better .can prevent a malicious user's forgery attack and have the security properties of proxy signature.

In order to investigate the influence of different shot peenings on the rolling contact fatigue life of case−hardened steel, the thrust type rolling contact fatigue test was performed with a ball−on−disk contact tester. In this study, the case−hardened steel disks were treated by the fine particle peening with a shot diameter of 0.05 mm and the normal shot peening with a shot diameter of 0.30 mm. The surface hardness and the surface compressive residual stress of the test disks were increased by these peenings. On the other hand, the surface roughness of the test disks was increased by the normal shot peening, and was decreased by the fine particle peening. The rolling contact fatigue test showed that the rolling contact fatigue life of the test disks was improved by the fine particle peening, and was not improved by the normal shot peening. The rolling contact fatigue life of the test disks became longer as their surface roughness became smaller. Therefore, it follows from this that the fine particle peening, which can provide the increase in surface hardness and the decrease in surface roughness, is good for the increase in the rolling contact fatigue life of case−hardened steel.

A Reversed-Phase High Performance Liquid Chromatographic method was developed for determining free Amino Acids in Burley Tobacco. The test was done by OPA/3-mercaptopropionic Acid as the pre-column derivatising reagent. Chromatographic column was Elitte C18 column (4.6mm×250mm i.d., 5um). Mobile phase A was 18mmol/L NaAc (PH=7.2) including 0.002% (v/v) triethylamine and 0.3% (v/v) furanidine. Mobile phase B was 100 mmol/L NaAc (PH=7.2) -Acetonitrile- methanol (v/v=1:2:2). The column temperature was 40°C and the flow rate was 1.0ml/min. The fluorescence detector was used with 350nm excitation wave length and 450nm emission wave length. The average recoveries of the method ranged 95.3% to 100.7% with the relative standard deviation of 2.32%~9.24%. The method is simple, accurate and has good repeatability. The results of the determination of seventeen kinds of free amino acids in burley leaves which were produced by way of different ratio of cake fertilizer and inorganic fertilizer. The results show that aspartic acid has the highest content however ratio of cake fertilizer and inorganic fertilizer. The most contents of free amino acids are increased and then gradually decreased with the increase of organic manure. The most contents of free amino acids are very close at the ratio of 15%:85% ratio and 30%:70% between cake fertilizer and inorganic fertilizer. The total content of free amino acids is the highest at the ratio of 30%: 70% between cake fertilizer and inorganic fertilizer. Considering comprehensively, the quality of burley leaves is the best at the ratio of 30%:70% between cake fertilizer and inorganic fertilizer.

In order to study the effects of filter ventilation on flavor constituents in cigarette smoke, the deliveries of 20 added flavor constituents (showed in table 2) and routine components (including TPM, nicotine, tar, carbon monoxide and water) in cigarette mainstream smoke were studied when filter ventilation were 0, 10%, 30%, 50% and 70% respectively. The flavor substance test was done by addition of standard samples. The flavor constituents were identified and determined quantitatively by gas chromatopraphy -mass spectrometry (GC/MS) and capillary gas chromatography (GC) and their condensate were separated by simultaneous distillation-extraction (SDE) and GC. The deliveries of routine components in mainstream smoke were determined according to international standard methods. It was found that the flavor constituents and routine components in mainstream smoke decreased in different proportions as the filter ventilation increased. Carbon monoxide and tar decreased more than nicotine. The flavor constituents with lower boiling points and molecular weights decreased more than those with higher. With the increase of filter ventilation, not only is the amount of smoke components reduced and the smoke taste weakened, but also the composition of smoke is modified and the quality of aroma changed slightly. Therefore, when low-tar cigarettes are made through the use of ventilation technology, different constituents and their changes should be taken into account in order to determine appropriate leaf group blending and flavoring.

The energy utilization is crucial for electric or hybrid vehicles to solve the problem of braking energy recovery, especially of low speed energy recovery. In this paper, the energy transform model of electric vehicle in braking state is analyzed, and the half bridge control main circuit was selected. The energy recovery strategies and methods on the breaking process of low speed were researched. The concrete realization of parameters decision and system control was given. The results show that the energy recovery strategy and electric vehicle model can improve the energy transform efficiency in low speed state.