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Y-type insulator string has advantages of external insulation and reduction of corridor width. This paper establishes a 3D finite element model of Y-type composite insulator string of 1000 kV AC double-circuit transmission line, including tower, insulator, grading rings, phase conductors and other hardware fittings, the model is used to calculate electric field distribution of composite insulator and grading ring. Then the parameters of grading ring are optimized based on the electric field results. According to the results, the optimum parameters of the racetrack grading ring are R=700 mm, r=120 mm, H=200 mm. The results can give a reference for design of UHV AC Y-type insulator string.

In this paper, aimed at suppressing the noise amplitude modulation jamming for a novel combined modulation radio ranging system, which transmits the waves combining pseudo random binary phase code (PRBPC) with linear frequency modulation (LFM), a signal processing method based on the empirical mode decomposition (EMD) and reconstruction of the target correlation peak signal is presented. Firstly, the correlation detection output signal of the ranging system is theoretically derived and proved to meet the condition of the Intrinsic Mode Function (IMF). Then the EMD processing for the target correlation peak signal, completely covered by the noise amplitude modulation (AM) jamming, is done and decomposes the signal into several IMFs. The difference of certain main IMF between the target signal and the strong jamming is utilized to reconstruct the target correlation function as the input signal of the detecting part. It is proved by simulation that the processing gain to the noise AM jamming can be significantly improved and the main lobe of the reconstructed correlation peak signal is more obvious, therefore it can be more easily identified.

Poor energy output and high cost are the key factors to inhibit the development and application of microbial fuel cells (MFCs). Different types of modification techniques for anode material are suggested to improve power performance in MFCs. nanoFe2O3 is characteristics of no toxicity, biocompatibility and low cost. In this work, stainless steel mesh (SSM), ultracapacitor activated carbon with SSM (AcM), Fe2O3 added AcM (AMF) anodes are investigated to improve MFCs performance. The highest maximum power density (806 ± 26 mW·m-2) is obtained in AMF anode, which is 11 % higher than that of AcM (730 ± 27 mW·m-2), and 57 folds higher than that of SSM anode (12 ± 0.7 mW·m-2). The semi-conducting properties of passive film on the anode surface play a rather important role in anodic reaction by Mott-Schottky analysis. Tafel test demonstrates that the exchange current density (8.36×10-4 A·m-2) is improved by 20 % for AMF compared with AcM control (6.93×10-4 A·m-2). These results show AcM is suitable as MFCs anode, and further addition of Fe2O3 can increase the extracellular electron transfer in that way increase power production in MFCs.

A series of fatigue tests is performed for polymethyl methacrylate (PMMA) specimens without scratches and with scratches. The scratch depth is set to be 0.2mm, 0.3mm and 0.4mm, respectively. Based on the experimental results, it can be deduced that contained fatigue limit of specimens with scratches significantly decreases compared to specimens without scratches. Besides, contained fatigue limit decreases gradually with scratch depth increasing from 0.0mm to 0.4mm. Consequently, it can be concluded that fatigue properties of PMMA will decrease when there exists scratch and for scratch depth from 0.0mm to 0.4mm, fatigue property decreases remarkably with deeper scratch.

Apply driving assistance system to vehicles can significantly reduce accidences and thus attracts much interest nowadays. However, most existing systems are designed specifically for small vehicles and always suffer from drawbacks such as low pedestrian and vehicle detection accuracy and long detection time. To solve these issues, in this paper we develop a driver assistance system based on radar and camera, which can be applied to large vehicles and can detect vehicle and pedestrian simultaneously. Specifically, we combine the image subtraction technique and histogram algorithm to perform pedestrian and vehicle detection to improve detection rate. What’s more, this system can automatically determine whether the object is inside a danger region. If yes, an associated warning signal will be triggered to alarm the driver. Experimental results show that the successful detection rate is sufficiently good and the detecting speed is fast enough to timely alarm the driver to avoid accidents.

Rare earth magnesium alloys and Mg-Zn-Cu alloys were prepared by gravity casting and direct squeezing casting respectively, and the corrosion performances of three kinds of Mg-Zn-Cu alloys were compared in this paper. The results indicate that adding rare earth elements and direct squeezing casting process can significantly increase the mechanical properties of magnesium alloys, and aluminum can improve the corrosion resistance of magnesium alloys.

STK is the important tool of satellite simulation and analysis, it can be intuitive and vivid reflects the state of satellite orbit. The STKX component allows user code to respond by writing incident response and control the user to the operation of the GUI interface STK components, in order to enhance the application of interactive ability. In this paper, through the application of the STKX component, and the design of Qt Chinese interface, realize the function of orbit dynamics simulation, 2D and 3D images and satellite images show function; To realize the Two-way exchange of information. Convenient man-machine interface and Chinese interface implements the intuitive and mutual assistance, and operating process of the simulation.

According to the principle and the structure of attitude module of modular spacecraft,a matlab/simulink model library for attitude control module was build to resolve the problem of flee-tly modeling.Then its validity was proved by a simulation example.The library was embedded into the platform of matlab/simulink,so it is easy to use and can be serially improved.The methed will be helpful for modular spacecraft’s design and simulation.

In order to achieve high accuracy, we present a new calibration technique aimed at blind steganalysis. The calibration can be considered as a preprocessing of stego image before extracting the features. The extracted features will be more effective for our classification [1] Moreover, the calibrated feature was used to train SVM (Support Vector Machine)[2], a nonlinear classifier, which is effective in class separation. For comparison, we conducted extensive experiments and drawn a conclusion that the steganalytic scheme based on our novel calibration can detect the stego information with high accuracy. Experimental results demonstrate that our proposed scheme outperforms the best effective JPEG steganalysis having been presented.

The emergency of a new computing pattern must be supported by powerful mathematical theory, weak theoretical supported ideology does not have a strong vitality, and which will become vulnerable. As being a new theory, the DNA computing treated as a new computational pattern also need a lot of basic theoretical research system. This article describes the nature of DNA computing, given the equivalence of DNA computing pattern with traditional computer under the support of automata theory system, further analysis and understanding the DNA computing pattern.

There are many disadvantages for Image enhancement with Mallat wavelet, such as huge computation, bad real time capability and difficulty to realize by hardware. To solve these problems for enhancing non flowing and discontinuous image, introducing the use of lifting wavelet with the adaptive predicting coefficient and the updating coefficient. The experiment result shows that the image enhancement based on lifting wavelet enhances the image and restrains the noise, brings better effect of image enhancement, and improves the arithmetic speed.

The body control module (BCM) functions are designed on one platform of BATC high-end passenger-cars; According to the CAN bus specification and BCM functional requirements specification, and by virtue of the network bus development/test tools, cabinet, bench and real car, the BCM functions are tested and validated, test report is used to improve BCM and make it more perfect.

The experiment was carried to study the fermentation regularity of different maturity, so as to provide theoretical basis for the effective storage of Lingwu long jujubes. The results showed that with the increase of maturity, the fermentation rate of fruits also increased, and the fermentation rate of eight, nine, ten mature fruits had significant differences, and the seven, eight mature were not. Based on the fermentation regularity and other quality indicators, the conclusion was that the storage of Lingwu long jujubes should be appropriate to eight mature jujube.

According to the experiments study of sulfuric acid saline soil, the formula of compression coefficient with the changes of moisture content, salt content, initial dry density and temperature is presented, and the law of single influencing factor on sulfuric acid saline soil compression are analyzed in the paper.

Using fine sand as aggregate, bentonite, gypsum and cement as cementing materials, wood powder as admixture, through two stage proportioning tests for similar material to swelling rock, the similar material displaying expansive properties of swelling rock is obtained. Physical and mechanical performance experiment indicates that the similar material could meet swelling characteristics and other physical and mechanical requirement of swelling rock, which could be used in similar material model test for swelling rock.

By using outlier data mining, this paper studied customs risk management in China. Our research contents are summarized as follows: First, we study the status of Customs risk management and we study other scholars’ research of the outlier data mining. Second, we introduce index of outliers and we use outlier data mining to establish a risk estimation model. Finally, we test the affectivity of this model by empirical analysis.

D2D communication can facilitate diverse local services and ease the load of base station. However, traditional resource allocation schemes for D2D communication were simply aiming at maximizing the sum-rate capacity or minimizing the mutual interference of the system but ignoring users satisfaction, which were discussed usually under the premise that the system resource was sufficient for the fixed number of users or restricted in the flexibility of spectral reuse. In the resource constrained system, aiming at maximizing average system satisfaction degree, a more flexible resource allocation scheme based on optimized artificial fish swarm algorithm (USRA-AFSA) is proposed in this paper, in which user satisfaction degree models are established and different D2D links are allowed to coexist on the same subchannel. With solutions mapped onto artificial fish, the simulation results show that the proposed scheme achieves higher average system satisfaction degree and larger system throughput compared with other schemes.

A numerical simulation method for the wind field over complex terrain is developed in this paper. The complex terrain is represented by a surface, which is established by the surface spline method basing on the contour line of the map. Then it is divided into panels containing vortex ring singularities. The singularity distribution is solved by combining with the potential flow theory and the boundary condition of terrain surface. Finally, the wind field is simulated by linear superposition of the uniform stream and the induced velocity of vortex rings. A numerical example is studied, and the result indicates that the method proposed in this paper could describe the terrain much more accurately and provide a reasonable result of wind field distribution, but has a simple and efficient procedure, which is suitable for the engineering use in flight dynamics.

By using on-orbit replacement and assembly technology, some fresh ideas and methods for the design, produce and application of spacecraft were put forward. Universal structure is one of the most basic requirements of On-Orbit replacement, assembly. Module structure must obey the rules of the Operationally Responsive Space (ORS). According to the degree of spacecraft module division, two module structures were proposed, and the complex structure was analyzed to verify the correctness of it.

It is important for the research of flight characteristics to master the distribution of wind field and the character of turbulence intensity in a complex-terrain mountain. Based on the potential flow theories in fluid dynamics, a numerical simulation method of complex terrain including asymmetrical and symmetrical mountains has been developed in this paper. In particular, asymmetrical mountains are simulated by the combination of two transformed quarter-semiellipsoids. Furthermore, mountain-induced airflow is calculated based on potential flow theory, which could reflect the characteristic of wind field. As an example, the wind field near Dingling airport in Beijing has been simulated and analyzed by this method. The results demonstrate that this method is suitable and accurate for engineering practice, and also applicable for flight dynamics characteristics analysis of aircrafts.

According to the experiments study, the formulas of strength with the changes of moisture content, natural dry density, cement dosage are presented. Applicable range of cement mixing pile to consolidate soft soils is determined which can be used to guide the using of cement mixing pile and provide reference for design or research departments at the same time.

Loess is widely distributed in the eastern part of Qinghai Province, because of its special nature,a large number of high and steep slopes have been formed in this area, sliding under the influence of human and natural factors,leading to economic losses. Fenghuang Mountain landslide is located in the middle district of Xining City, a the loess-mudstone contact surface landslide with its upper loess bedding sliding along mudstone contact surface. Based on the sliding mechanism, strength reduction method for slope stability analysis has been applied, showing the landslide is in the creeping stage, with the critical safety factor of 1.3 and had better taking the corresponding control measures.

For the purpose of grid peak load shifting, chilled water storage has been paid more and more attentions to integrated with air-conditioning system. In this paper, a new air conditioning system with directly chilled water storage is given. With peak-valley Price, cost for power consumption can be saved 15%-20% by coordinated operation between chilled water storage system and air conditioning system. By sensitivity analysis of system economic performance on ratio of peak price to valley price, it is revealed that with much higher ratio of peak price to valley price, not only system economic performance can seldom be improved, but also chilled water storage is restricted for engineering utilization. This paper supplies theory reference for engineering application of chilled water storage technology.

Fatigue properties of the newly-formed and served canopy PMMA, which was applied in a certain airplane, were studied by experimental method. In order to gain the fatigue strength in the designated life, experiments based on up and down method had been conducted. The S-N curves of the PMMA were acquired based on three-parameter exponential function. Fatigue properties of the canopy PMMA in the two different condition of service were discussed. The results of analysis showed that fatigue properties of the served PMMA did not decrease significantly compared to the newly-formed PMMA.

The trend towards portability of electronic products expands the application of rigid-flex board, which has become one of the hot spots in PCB industry. Along with the improvement of assembly technology, the improving design of rigid-flex board appears. High Density Interconnection (HDI) is one of the design directions. The key manufacturing parameters of buried /blind via process in manufacturing process of HDI rigid-flex board was studied in detail including material selections, laminate process, drilling process and via metallization. Better manufacturing parameters of buried /blind via were obtained through orthogonal design. It was found over 99.9% vias could pass the test on electrical performance.

Fatigue properties of canopy PMMA with typical damage, which are two different depth scratches of 0.3mm and 0.4mm, are studied by experimental method. In order to gain the fatigue strength about the depth scratches of 0.3mm in the designated life, experiments based on up and down method had been conducted. The S-N curves of the PMMA about the depth scratches of 0.3mm were acquired based on three-parameter exponential function. Fatigue life of the PMMA with the depth scratches of 0.4mm under different stress levels is obtained by grouping method. Fatigue properties of the canopy PMMA of the two different depth scratches were discussed. The results of analysis showed that compared with the depth scratches of 0.3mm, fatigue properties of canopy PMMA with the depth scratches of 0.4mm decrease significantly.

Load imbalance of power grid leads to more peak-load power station built with huge capital cost and some environment effects. As a peak shifting technology, thermal storage technology has attracted more attentions. A new operating mode of chilled storage process integrated with air-conditioning system is proposed, and its performance is analyzed. The results show that the new operating mode can get more than 5% of power saving than the traditional mode, and achieve more than 40% power cost saving based on air-conditioning without chilled storage, both of which result from the good integration of chilled storage process with air-conditioning system. The new operating mode gives the new direction of thermal storage technology application.

P. cocos, B. ochracea, P. lactiflora, A. dahurica were procured and identified and seperately extracted using water (ethanol, methanol) in the ultrasonic cleaner. TPC, DPPH scavenging ability and reducing power (RP) were determined. The results from this study showed that P. lactiflora had the highest content as 18.62 mg GAE/g dw in ethanol, whereas P. cocos contained only 0.37 mg GAE/g dw in water and P. lactiflora exhibits the highest capacity (68.97%) to reduce DPPH in methanol extract with lowest IC50 value of 1.12 mg dw /ml and 1.14 mg dw /ml in ethanol extract at a concentration of 1.6 mg dw/ml. In RP assay, P. lactiflora had highest FRAP values (37.65 mg AAE/g dw in methanol extract), and P. cocos with least activity 3.25 mg AAE/g dw. The RP value has a apparently positive correlation with TPC and DPPH scavenging activity. TPC is remarkably related to its overall antioxidant ability. P. lactiflora could be selected as an excellent antioxidant for functional foods as well as pharmaceutics.

According to the experiments study of sulfuric acid saline soil, the formula of compression coefficient with the changes of moisture content, salt content, initial dry density and temperature is presented, and the interaction law between the various influencing factors on sulfuric acid saline soil compression are analyzed in the paper.

We propose a universal single-radio multi-channel vehicle node structure (VNS) in NS-2 for VANET simulation. VNS can support different single-radio multi-channel MAC protocols, while in this paper we implement a split-phase mode MAC as channel coordination mechanism, with a three-way handshake as channel negotiation mechanism. Simulation results in sparse, dense and moving scenarios indicate that VNS is a preferable solution for simulation of VANET.

It has important scientific and engineering applications for near-space platform to design the buoyancy-lifting aircraft with both bigger volume and higher aerodynamic efficiency. This paper provided a design of a new concept V-shaped airship which has a capacity of buoyancy-lifting configuration than the same-weight class conventional airship. In addition, two engines could provide rolling, yawing and pitching moments for the V-shaped airship by changing directions and creating different thrust. Based on the thick aerofoil, the geometry of this V-shaped configuration was then used to develop an aerodynamic estimating model for the V-shaped airship. It renewed estimating methods for the added mass, inertia, the forces and the moments including aerodynamic and engine thrust of the V-shaped airship. Then this paper described a 6 Degree of Freedom (DOF) dynamic model for the V-shaped airship. The open-loop disturbance characteristic of the dynamic model was analyzed across a range of flight conditions and the added mass of the V-shaped airship were compared with the same weight-class teardrop-shaped dull-hull airship. Finally, the characteristics of buoyancy and lift between V-shaped airship and dull-hull airship were compared at different velocity. The results show that the aerodynamic efficiency of the V-shaped airship is improved obviously from the same-weight class dull-hull airship across a range of flight velocity.

Aimed at preventing the problems of axial movement, step blemish and rolling overlap piece of skins which make from the imbalance of axial and tangential force because of asymmetry of parts in size and shape, the paper adopted finite element method (FEM) to simulate CWR technique of typical asymmetric shaft part, and analysis systematically axial force and axial displacement. Then we can judge axial offset by axial displacement of central point of billet. The results of the study indicate that FEM can manifest the axial deformation of asymmetric shaft parts in CWR, which provides theoretical foundation for the promotion of CWR technology in the application of asymmetric shaft parts manufacture.

Rolled-piece end quality is one of key factors to decide material utilization ratio in cross wedge rolling (CWR). Good workpiece end quality can improve material utilization ratio effectively. In the paper, by adding the block wedge near the end of mould, it can block surface metal which flows faster in the axial direction and avoid the end concavity of rolled piece. The material loss will not be present and good end quality rolled piece will be produced. The results are significant for improving material utilization ratio and promoting applications of CWR.

The dual-drive system to be used in the tunnel boring machine (TBM) is a new kind of high-power planetary transmission system. On the basis of the system’s transmission theory and the bond graph principle, the bond graph model of the dual drive transmission system is established and then the state equations are deduced. Based on this model, dynamic performance of the system is simulated by means of MATLAB/Simulink and the dynamic response curves of the speed and torques are acquired. The simulation response illustrates that the bond graph model of dual drive transmission systems is accurate. In addition this system is suitable for three types of TBM and can satisfy the requirements of dramatic changes of load in the running of TBM.

Multi-wedge synchronous rolling by cross-wedge rolling is one of the most advanced methods that can form rolling railway axis. Its rolling quality mainly lies on inner transversal stress and shearing stress of rolling workpiece. In this paper, based on the rotated theory of multi-wedge rolling, through using Ansys/Ls-Dyna FEM software, multi-wedge synchronous rolling railway axis by cross-wedge rolling is simulated. It has been systemically researched that technical parameters effect transversal stress and shearing stress. In the meantime, the calculating model is verified by experiment. Through this study, It is obtained that the law of technical parameters effect on rolling railway axis by multi-wedge synchronous cross-wedge rolling. These research conclusions can provide scientific basis for rolling railway axis by multi-wedge synchronous cross-wedge rolling and rolling better quality.

Due to complexity of sound environment, the performance of speech enhancement is degraded greatly based on traditional beam-forming when directivity of arrival of sound and number of sound are not been estimated precisely. In this paper, according to characteristics of handle-communicated equipment, a method on suppression of environmental noise and disturbance is provided. Beam-forming on speech wideband in desired angle is realized by designing a two-dimensional FIR filter which has fan structure in pass-band and wedge-shaped structure in transition-band. The filter can suppress noise and disturbance out of main-lobe desired. The simulations demonstrated that the filter designed is effective.