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With the slope unstable rock masses of a stope in Longsi mine, Jiaozuo City, China as the target, we computed and analyzed the stability of unstable rock masses using a limit equilibrium method (LEM) and a discrete element strength reduction method (SRM). Results show that the unstable rock masses are currently stable. Under the external actions of natural weathering, rainfall and earthquake, unstable rock mass 1 was manifested as a shear slip failure mode, and its stability was controlled jointly by bedding-plane and posterior-margin steep inclined joints. In comparison, unstable rock mass 2 was manifested as a tensile-crack toppling failure mode, and its stability was controlled by the perforation of posterior-margin joints. From the results of the 2 methods we find the safety factor determined from SRM is larger, but not significantly, than that from LEM, and SRM can simulate the progressive failure process of unstable rock masses. SRM also provides information about forces and deformation (e.g. stress-strain, and displacement) and more efficiently visualizes the parts at the slope that are susceptible to instability, suggesting SRM can be used as a supplementation of LEM.

A local adaptive neighborhood model is proposed in this paper in order to deal with the mistake judgment in the existing scanning beam point cloud denoising algorithms. Such a model regards larger curvatures as the potential noises, can select angle thresholds of noise points and the median values of filtering windows adaptively, so as address the issues of mistake judgment and missing judgment of the point clouds denoising algorithms with different curvatures. The adaption theory in the angle threshold denoising algorithm classifies the noise points and data points. Therefore, it can ensure the smoothness in low frequency, and as well keep the high frequency characteristics. The new method improves the accuracy of median filtering, prevents the diffusion of noise, remove noises effectively while preserving sharp features, and avoid fuzzy data margin.

Meteor burst communication is an important communication mode for a number of possible civilian and military applications. This paper proposes a channel modeling and simulation based on OPNET for meteor burst communications. Analyzing the characteristics of underdense meteor burst channel, the multi-layer node models of master station and slave station are presented to create practical simulation scenario of meteor burst communications. The simulation processes of half-duplex communication as well as full-duplex communication are designed to execute simulation. The results demonstrated that the channel model based on OPNET is consisted with meteor burst communication very well, and full-duplex communication is better than full-duplex communication in effectiveness.

The tensile experiments were carried out under the condition of different pulse current on pure aluminum to analyze the effect of pulse current on the mechanical property such as tensile strength and elongation on material. The results show that pulse current could improve the mechanical properties and with pulse current the elongation of the aluminum increased to 19.5% and its tensile strength drops to some extent with the increase of electricity. At the same time, the dislocation structure features under different current density are also different. Without pulse current, dislocation is distributed as group unevenly. But when the current density J=8×102A/cm2, dislocation morphology changed into a mass of dislocation cells and moved to the grain boundary. Part of the cell walls formed grain boundary and then small angle subgrain formed. With the increase of current density, dislocation walls are arranged neatly and parallel to each other and at last single dislocation wall will be split into two or more parallel dislocation walls and form structure of striped band.

This paper introduces the design of an airborne pulse Doppler radar jamming system tester. Based on a detailed analysis of the functional structure of the radar-jamming system, we summarize the important failure mode. To achieve fault location and performance testing, we have developed an automatic detector for the radar-jamming system, the device uses a mode of hardware platform and software platform, and it can reach the purpose of fault location by a method of encouraging input and measuring the output of each of the radar-jamming system failure mode individually. The automatic test instrument has the features of simple operation, high degree of automation, real-time, scalable, and actual use of running proves it to reach the required design specifications, the test with good results.

With the development of computer technology, the intelligent technology and the virtual instrument technology is becoming more and more important in the testing field, the radar automatic detection system described in this article concludes virtual instrument system, detection platform and troubleshooting software. The system can individually and comprehensively and quickly check the performance of the equipment for automatic diagnosis, greatly improving the technical support capabilities of the equipment. Functionally, it can be easily expanded and upgraded, with a high value of promotion and application prospects.

In the big cities, any construction nearby the metro structure become critical to the safety of the metro,especially for deep foundation pit engineering.In such case,Pile-anchor supporting system is normally used, however different deformation shape of the supporting wall will bring different deformation of the metro structure.This paper analysed the relations between the pile-anchor supporting system and the nearby metro structures and stated how to control the nearby metro structure deformation through the design of the Pile-anchor supporting system.The analysis showed the following conclusions:If the nearby metro structure is closer to the ground surface, it will be more sensitive to the deformation of the piles-anchor system;Shape 1 & 2 are better to control the metro structure deformation,Shape 3 will result bigger settlement;the metro structure above and in the middle of the foundation bottom level are very much influenced by the deformation of the piles;If the deformation of metro structure exceeds the allowable value, other measures should be considered.

Belonging to the Bentley Microstation series which work as one of the BIM platforms, the Bentley Power Rail Track shows huge advantages in the railway design for its visibility, high efficiency, advance, reliability and so on. This paper introduces the way to build the digital terrain model, alignments, cross sections, turnouts and to display the three-dimensional model of the railway for the Bentley Power Rail Track 3D railway design software. It provides application preparation for the BIM railway design and achieves the preliminary exploration of BIM applications. Bentley Power Rail Track proves capable of the BIM railway design.

For the design of prestressed concrete sleeper, design methods and standards in different countries are different. America and China design sleeper by the allowable stress method, UIC design by probability limit design method. China has design II-sleeper by the method of reliability, but the theory is not immature so that II-sleeper appeared a lot of cracking problem. In recent years, designing IIIa-sleeper still use the allowable stress method. By contrast of process of designing IIIa-sleeper in China and America, include design load moment, the prestress loss, bearing capacity of structure, test and so on. Get the main difference of designing sleeper in China and America, and the rationality and practicability of different design method.

Prestressed Concrete Cylinder Pipe (PCCP) consists of a steel cylinder lined with concrete, then helically wrapped with a wire and coated with a dense mortar. PCCP has excellent structural properties, so it is widely used in various water-transportation projects around world. This paper presents a review of development of PCCP in China, which was summarized as three stages: the period of exploratory development, the period of cooperativedevelopment, and the period of independent development. The development process of design and production technique, the application in China, the construction and development prospect of PCCP were made a detailed discussion in each stage.

Requirement is the cornerstone of the project,A good requirements specification is the key to the success of the project, requirements specification content from the user's requirements. How to accurately, effectively elicitation of the user's requirements This paper on the different application system of nuclear power enterprise used by the methods in requirements elicitation were discussed. By choose the correct method can effectively elicitation of the user's requirements.

The feature extraction and detection problem of network information abnormal behavior was researched in this paper. The network attack tended to ambiguity in hidden, and the abnormal behavior of network information is referred as a data signal series, and it was existed in the network information space with strong interference. Traditional detection method was hard to detect the abnormal signal. On the basis of fractional Fourier transform (FRFT), an improved abnormal behavior feature detection algorithm of network information was proposed. The properties such as energy gathering and noise suppression of 4-order cumulant slice were taken in advantage. In the post processing of fractional Fourier transform detection, the post processing operator of 4 order cumulant was introduced in the detection algorithm, the post energy was gathered in the fractional Fourier domain, the signal accumulation was likely to be increased, and the interference noise could be restrained effectively. Simulation results show that the improved algorithm has perfect noise suppression performance, and it can detect and extract the abnormal behavior feature in the network space to maximum. The detection performance is improved greatly, and the research result can be applied in the network information warfare and network security areas.

A novel mutiscale and directionally adaptive image transform called contour based directionlet tansform is presented. Directionlet transform (DT) has shown its charming performance in image processing, but it has scrambled frequencies. Laplacian Pyramid is employed here to separate the low frequencies before applying DT for avoiding the drawback. And an adaptive threshold algorithm is proposed for denoising. Numerical experiments are performed to assess the applicability of the proposed method. The obtained results show that the proposed scheme outperforms Wavelet and Directionlet transforms in terms of numerical and perceptual quality.

This paper develops a novel distributed jointly sparse optimization algorithm to recover the sparse signal, in which the joint sparse structure is used to improve the quality of recovery. In distributed networked multi-agent system, each agent collects measurement vectors and aims to recover its own sparse signal collaboratively in a distributed manner. We propose to use the factored gradient approach to calculate the solution iteratively, and introduce a energy vector of the current estimates as the consensus constrain which is updated by inexact consensus optimization for its distributed implementation. This algorithm does not require excessive data transmissions from distributed agents to fusion center, which reduces communication overhead and the computational complexity of the agents. Simulation results demonstrate that the proposed distributed algorithm has strong recovery performance and can reach global convergence as well as fast convergence rate.

Benzaldehyde was produced from oxidation of cinnamaldehyde by hydrogen peroxide in propylene glycol in the presence of sodium bicarbonate. Protic solvent demonstrated high selectivity and the yield of benzaldehyde could reach up to 82% in propylene glycol. The effect of solvent on the selectivity was attributed to hydrogen bond interaction between the oxidation intermediate epoxide and the solvent.

Based on the theories of the method of the finite element and the interaction between beam and rail, the common railway bridge: the continuous girder bridge and the simply supported girder bridge as an example, set up the integration of the calculation model of the line-bridge-pier on the continuous welded railway bridge, through the calculation software of Bridge Continuously Welded Rail (BCWR2010), the regular pattern of the effect of the bending force and the regular pattern of the longitudinal displacement distribution of the rail and bridge are analyzed.

Keywords: ion nitriding furnace cooling system vacuum system Abstract. About fuction of vacuum plasma nitriding furnace cooling system, and its design and calculation of main parts, in particular control of water consumption. The cooling water system have been set into the water flowing through the four heat shield, and gradually take the heat, then the coolant out by outlet pipe. Cooling water flows through layers of insulation to varying degrees of cooling, to ensure that each level of temperature, precise calculation of water flow can only be guaranteed to ensure the maximum water savings and cooling the furnace down. This article provide the basis for vacuum furnace cooling system design in the future.

A direct, efficient method for the problem of epipolar rectification in the uncalibrated casewas proposed. The method was based on minimizing a measure ofdistortion, by introducing anepipolar distance transform. The transform converted image intensity values to a relative locationinside a planar segment along the epipolar line, so it was robust to noises. The ratio of the distancesbetween two matching points in the epipolar lines was theoretically proved invariant to an affinetransformation for planar surfaces. To calculate the relative rotation between both cameras, thealgorithm was decomposed into three-steps to limit the distortion. Results show that the new measureis more appropriate for image rectification, and the three-step algorithm has obtained an accuracycomparable result both in estimation error and visual effect, especially when the initial epipolar linesare far from horizontal.

In this paper, we present a new nonlinear ternary interpolatory subdivision scheme which has the properties of convexity-preserving, circle-preserving and the limit curve iscontinuous. In each subdivision step, the newly generating points will be on the circle determined by the interpolatory point and its adjacent points. Numerical examples show that this algorithm is simple and curves generated by this subdivision scheme are fair curves.

The inelastic response constitutive description of metal material under different stress and wide temperature range is very important in many practical engineering. It can accurately reflect the level of material rate sensitivity and set up a simple and practical strengthening evolution rate. Take No.35 steel as an example; because of the action of load, temperature, time and other factors in its forming process, the creep relation is very important and complex. In view of this situation, the BC-BPNN (Based on Back propagation Neural Network), owing high precision nonlinear fitting ability has and good generalization ability, is applied to the research on creep constitutive relationship of 35 steel. At first, the creep relationship is numerically fitted using testing data of 35 steel; then, the fitting results is compared with the creep testing data. The results show that the applying of BC-BPNN to research on metal creep relationship has a strong practical value.

To solve the abnormal rail corrugation problem of Beijing Metro Line 4, the track structural parameters comparative tests were carry out in the Metro Line 1,2 and 4. Metro Lines 1 and 2 were chosen based of the Beijing Subway Survey and previous successful experiments. The comparative analysis was based off of rail static geometry, dynamic displacement and the lateral acceleration. The test results proved the stiffness of line4 is weaker than line1,2 and suggestions on steps to prevent and correct the metro rails abnormal corrugation will be formulated.

A new algorithm is proposed for digital watermarking by applying complex-valued linear-phase filter banks to low frequency-band coefficients of images in the DCT domain. The watermark is conveyed in the phase spectrum of the subband coefficients. The robustness of the algorithm is examined in JPEG encoding with different qualities and compared with the DFT-based approach. Because only low frequency-band DCT coefficients are applied to complex-valued filter banks, the computational load introduced by the complex-valued filter banks is kept low. The watermark decoding is only accessible to users with the key information, i.e., impulse responses of the complex-valued linear-phase filter banks that designed with time-frequency spread property.

In this paper, non-multiplier approximation of frequency transformation is examined. 2-D frequency response marking filters with sum of powers-of-two (SOPOT) coefficients are designed. The numbers of adders allocated to transformation coefficients are determined in the experiments so that the resulting 2-D filters preserve the stopband attenuation of the original 1-D prototype filters. Experimental results of 2-D wideband FIR filters with low arithmetic operations and computational complexity are presented.

In this paper, we firstly devise a p-ary subdivision scheme based on normal vectors with multi-parameters to generate fractals. The method is easy to use and effective in generating fractals since the values of the parameters and the directions of normal vectors can be designed freely to control the shape of generated fractals. Secondly, we illustrate the technique with some design results of fractal generation and the corresponding fractal examples from the point of view of visualization. Finally, some fractal properties of the limit of the presented subdivision scheme are described from the point of view of theoretical analysis.

Whether the resin canals of Cedrus deodara are caused by injuries is still controversial. In this paper, with the branches and trunks of Cedrus deodara taken as research objects, the resin canals in the phloem and xylem of Cedrus deodara are quantitatively and qualitatively analyzed and researched with the principles of wood science, aiming at exploring whether its distribution provided with regularity. The results showed that several parts showed relative stability, such as the morphological characteristics, anatomical structure, occurrence time, cellular component and quantitative characteristics and so on. In terms of occurrence probability and quantities, the resin canals generally occurred in the compression and lateral zones of branches while few in the opposite zone; the occurrence of the resin canals of trunks had an extremely close tie with the growth and insertion angle/direction of the branches of different areas and directions, etc. Therefore, from the perspective of formation time, Cedrus deodara belongs to the tree species with slowly-formed resin canals.

A gear meshing mathematical model was set up according to the tooth profile normal line method. The influence of the gear cutter-workpiece center distance on the tooth profile accuracy was discussed in spur gear cutting using a new type of gear cutter, with the center distance errors being ±0.005, ±0.01, ±0.02 and ±0.04 respectively. The results show that the machined tooth profile errors at the root circle is less than 1μm, while errors at other parts of the tooth profile are even smaller.

When the shield tunnel go through the bridge structure of high speed railway, it will affect the high speed railway bridge structure, thus influence to the bridge of track structure and ballastless track. Based on the Beijing subway tunnel go through the Beijing-Shanghai railway bridge section engineering examples, for the first time to shield under through the high speed railway caused the bridge pier settlements are analyzed. Combined with the actual monitoring data, the isolation pile during the period of construction bridge pier and Shield during through bridge pier during the period of settlement regularity of construction bridge pier, settlement regularity of Isolation pile as well as settlement regularity of the surface land are summarized analysis. During the construction of high-speed rail bridges and the soil to produce a certain degree of deformation, Shield Zone just above the soil settlement with a large deformation, both sides of the deformation gradually decreases, but the deformation is controlled. The use of the isolation pile reinforcement measures significantly reduced the influence by the Shield Construction and it can satisfy the requirement of high speed railway control standards

The recycling of waste is a worldwide development trends. The full use of all kinds of wastes in the material selection of the landscape design is the way that sustainable use of resources. The analysis of the status quo of material selection in landscape design, put forward use of waste types and specific design method, which plays an important role in the innovation and development of the landscape architecture industry.

Parts precision is one of the key points in industrial application of rapid prototyping technology (RPT), and also the pivot of RPT research, but presently high precision is hard to achieve. This paper focuses the emphases on the principle of error analysis. Obtain chord errors corresponding to the number of triangles with pro/E software during the STL, and the formula for computing stair errors taking the quarter of sphere for an example during the slicing. In the end, propose the measures to improve the principled errors, viz. sloping slicing, adaptive slicing, direct slicing and so on, and further propose the theoretical range of adaptive slicing thickness.

In the field of RPM( rapid prototyping manufacturing), accuracy and efficiency have become the bottleneck that slows down its development, so how to improve parts precision has been one of the hot research questions. A variety of factors are analyzed which have effect on parts precision , such as extrusion temperature, envelope temperature, extrusion velocity, filling velocity, slicing orientation, slicing thickness, filament-width compensation, and delay time, and then corresponding measures to improve parts precision is presented.

Multiple criteria decision making(MCDM) is widely used in selection from a set of available alternatives with multiple criteria, approaches to which includes fuzzy comprehensive evaluation(FCE), grey relational analysis(GRA), and technique for order preference by similarity to ideal solution(TOPSIS), and so on. First analyzes the limitations of various methods: only considering the overall effect of attribute indicators in the method of FCE, only considering the shape similarity of data curve between comparative scheme and ideal solution in GRA and only considering position approximation in TOPSIS. Second proposes a new method of comprehensive evaluation which takes into account both shape similarity and position approximation. The validity of this method has been further proved by an example of suppliers selection.