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Some engineering materials have excellent performances, but the machining of these materials is a problem. It is very inadequate to meet machining requirement only using traditional cutting tool materials. Therefore, exploring the machinability of difficult-to-machine materials and applying appropriate cutting tool materials have drawn much attention in metal cutting industry for guarantied product quality and productivity. Cubic boron nitride (CBN) has been recognized as one of the most suitable cutting tool materials due to its high hardness, high wear resistance, high chemical inertness, and excellent chemical stability in high temperature. Research on various aspects of CBN cutting performances has been conducted in recent years. This paper presents the progress on machining difficult-to-machine materials using CBN cutting tools.

Laser aided activating TIG welding was called LA-TIG. At first, the surface of weld was melted by the mini power laser protected by oxygen, and then the conventional TIG was used to cover the weld, which achieved the target of the weld with deeper penetration and narrower width. In this article, the weld bead morphology, arc images, microstructures and mechanical properties of laser aided activating TIG welding joint were analyzed. The results shows that the penetration increased significantly, excellent weld appearance and finger shape penetration were gained by laser aided activating TIG welding. It was found that the arc images of the LA-TIG was only the enlarged form compared with which observed in the conventional TIG and the arc constriction was also observed. LA-TIG weld exhibits better mechanical properties than the conventional TIG welding. Thus laser aided activating TIG welding was developed as a novel active welding method.

This paper summarizes the application of virtual simulation in the shipbuilding industry, especially points out research status of the key resources of shipbuilding (Ship Dock). Finally, the idea is put forward that a virtual simulation based on both intelligent algorithm and QUEST to improve the efficiency of ship dock.

In speech signal processing, the techniques of speech segmentation as front end of preprocessing have great importance in speech enhancing, coding and recognition. This paper analyzes the performances of several typical algorithms of speech segmentation, which are compared with each other. It put emphasis on the study of the algorithm based on the wavelet transformation. The smooth and gradual changing low frequency component can not segment the speech efficiently. In order to solve the problem, this paper put forward to an algorithm based on the cumulate energy of the wavelet transformation which promotes the precision of the segmentation on the phoneme level. But as a result of the wavelet sensitivity, it will present certain number of false spots. Therefore this paper proposes tow methods removing false spots. Finally it makes certain summary to these technologies.

This paper studies the temperature field variation of the chain link as well as the stress and deformation distribution of the pin which works in hot forging and stamping production line with heat recovery function. The approach is to build the model of the chain link with Pro/Engineer and apply it to the simulation with Pro/Mechanica. To be specific, it is to stimulate the thermal conduction of the chain link and the stress state of the pin under high temperature with Pro/Mechanica-Thermal and Pro/Mechanica-Structure module, respectively. The results are the temperature filed nephogram of the chain link as well as the stress and deformation nephogram of the pin. The simulation shows that:1) the temperature reaches 420°C at the contacts of the outer and inner plates at 600s, 2) the maximum stress of the pin is 112Mpa at the ends where the pin meets the outer and inner plates,3) the pins max deformation is 0.0159mm at the middle of the pin. Comparing the simulation to the actual temperature at the contacts of the outer and inner plates,which is measured ten times in advance with average of 439°C ,the simulation is favorable. According to the results above, graphite lubrication should be chosen for the chain and the pin can work properly with deformation rate of 0.795. By this way of simulating with Pro/Mechanica, complicated calculations and repeated tests can be reduced largely, meanwhile, useful parameters and mathematical model can also be provided for manufacturing and process control.

From the perspective of commercial banks, put the financial supply chain in the principal-agent relationship which is multi-agent and of multiple sections. This paper analyzed the principal-agent relationship between different subjects and commercial banks and information asymmetry. Secondly it also analyzes the information risk of supply chain finance caused by asymmetric information from in three aspects as risk types, risk behavior and risk loss. Finally it gives the Suggestions and countermeasures aimed to financial risk in supply chain information. It provides reference to main body understanding and the information risk of supply chain finance.

The third frequency adjustment is the key link of the grid frequency regulation. The admission of high capacity and rejection of small capacity policy on thermal power cause the lack of capacity of the third frequency adjustment. Wind power brings about a certain impact to the frequency stability of the power system, particularly, increasing the difficulty of the third frequency adjustment. The introduction of nuclear power into the third frequency adjustment has been proposed after analyzing the characteristics of the energy generation of different forms. This paper formulate the control strategy with the core of wind power decomposition, generator units grouping in the third frequency adjustment, after elaborating the technical feasibility and economic feasibility, and, come to a conclusion that the participation of the nuclear in the third frequency adjustment would guarantee the stability of the frequency of the power system with this control strategy in the case of the introduction of wind power to the system, by simulation analysis.

In view of the serious problems that low-rate reduction and excessive oil consumption of reducing oil guns which are used in the depleted EAF, analyzing the jet mixing process through the CFD simulation with the method of liquid level tracking, we find that the purpose of mixing slag layer, guaranteeing matte layer precipitation and saving oil can be achieved by changing combination of gas rate of mixture injected by the oil gun, jet speed and insertion depth. The results of this paper provide a theoretical foundation for optimizing reducing technical process of the slag cleaning furnace operation in a copper industry Company.

Recently, voice dispatching telephone is applied as one of information interactive by power grid dispatching in China, playing a significant role in the progress of power grid dispatching. However, with the increasing of grid scale, more and more information should be figured out by dispatchers. Conventional dispatching telephone in communication presents enormous challenge, thus, much effort should be made to solve this problem. In the article, the shortcomings of dispatching telephone in communication are systematically analyzed by the point of our actual country power grid dispatching. To remedy telephones shortcomings, text technology is introduced and a uniform dispatcher interactive platform is formed. This platform meets the requirements of interactive in power grid dispatching perfectly.

The geotechnical consolidation test is used to detect the soil deformation under all levels of vertical load. Consolidation parameters play a vital role in the basal design of the buildings. But the lever consolidometer covers too large area, and needs high labor intensity. The pressure consolidometer is not convenient to find leak, noisy, and is affected by the power supply. We developed the hydraulic consolidation system, which is aid to make consolidation tests of the soil samples. The hydraulic consolidation system is composed of the hydraulic pump used as a pressure source, the hydraulic piston cylinder used as the load transfer device, intelligent instrument and solenoid valve. Through the comparison of the test by three methods, it proved that the test results are identical. The coefficient of variation of the parameters is less than 0.1, while its efficiency is 31.33 times higher than the lever test, 6.86 times higher than the pressure method.

Central wavelength and pass band width characters of S-polarization and P-polarization will separate when the filter is tilted. This paper gives us multi-layer films structure from one design method which adopts three refractive index materials. Simulation calculations of three concrete filter designs for single cavity and three cavities prove that the method is feasible.

The primary aim of research is to improve the speed of underwater glider to overcome the influence of ocean currents. In the paper, an autonomous underwater glider with pump was developed, and its vertical plane motion equations were established. In addition, the glider’s vertical plane motions were simulated. The results show, compared with no thrust, when the amount of volume change is 0.8L and the pump jet thrust is 15N, the glider’s resultant velocity and its horizontal velocity are double. When the pump thrust increases to 40N, the glider’s resultant velocity and its horizontal velocity are triple. It has also been confirmed that there is a best neutral buoyant pitch angle that can make the glider’s horizontal velocity reach the maximum in a different amount of volume change.

A fast stereo video coding method based-on C-Means Fuzzy Hopfield neural network and AVS (Audio and Video coding Standard) is presented in this paper. In the system, an AVS encoder encodes the left-view sequence. For the right-view sequence, combined predictions from the temporal or disparity domains are exploited, with a hierarchical two-stage neural classifier for fast mode decision. Experiment results show that our method can achieve up to 30% of time savings with nearly ignored quality degradation and only 7% of bit-rate increase.

A web replay method is proposed in this paper for highlights in soccer videos. Firstly, automatically detection and fine-grained semantic annotation are introduced for soccer highlights. Secondly, an adaptive grass color model and several heuristic rules are used to improve the performance of the method. Finally, a database for highlights is established for web service. Experimental results show that the proposed method has excellent analyzing speed, accuracy and practicability.

By collecting the major group buy websites data, this paper using factor analysis and cluster analysis in data mining methods to analysis it, classify the group buy website, find and analysis the group buy website operating key strategy.

The solar energy is the most promising energy to solve energy crisis and environmental problem. Quantum dot can be applied to solar cells in two structures of QDSC to improve the energy conversion efficiency. The two structures are p-i-n type QDSC and quantum dots sensitized solar cells. The energy conversion efficiency of p-i-n type QDSC may increase up to 45%. Both CdSe and CdS quantum dot can be used as the sensitizer of the QDSSC and each of them has its demerits and merits, but the conversion efficiency of QDSSC is low if they were used respectively. Thus, in order to overcome their demerits respectively, we could try to combine their merits. QDSC is the most promising technique to solve the problems of solar cell. But before large-scale application their efficiency and stability should be improved.

Using scanning probe microscopy (SPM) technique, the electronic properties of Ge/Si quantum dots (QDs) have been characterized. Our results demonstrate that a layer of a disordered structure is formed between the Ge/Si QDs and the surface of Si substrate due to the defects in QDs during the bias voltage applied. That is, a double tunneling system in which the Coulomb blocking effect can be observed is constructed during the electronic measurement for the single quantum dot (SQD).

Recent progress in the growth of ordered Ge/Si quantum dots (QDs) is reviewed. We focus on the detailed progresses of the Ge/Si multiple layers QDs and the preparation of Ge/Si QDs by ion beam irradiation. In addition, the growth of Ge/Si QDs on patterned substrate by using different preparation methods are also well discussed, such as nanosphere lithography technology, extreme ultra-violet interference lithography technology, nanoimprint lithography technology, etc.

Silicon substrates were implanted with Si ions at an energy of 60 keV to a dose of 5×1015cm-2followed by a thermal annealing at various temperatures up to 950 oC. Photoluminescence (PL) and infrared absorption (IRA) techniques have been used to characterize these samples. The PL peak positions at 2.07 eV and 1.93 eV undergo redshifts with the increasing annealing temperature. The two IRA peaks at 1080 cm-1and 800 cm-1are ascribed to the Si-O-Si asymmetric stretching and the Si-O bending vibration, respectively. The experimental results indicate that Si nanocrystals embedded in silicon oxide layer can be formed at the annealing temperature 800 oC or higher.

Recent progress in the computer simulation of strained SiGe channel p-MOSFET performance is reviewed. The electrical characteristics of strained SiGe channel p-MOSFET, such as threshold voltage, subthreshold characteristics, output characteristics, transconductance, quasistaticC-Vcharacteristics and transfer characteristics, and the effects of Ge mole fraction on electrical characteristics, are well discussed. Finally, the development of strained SiGe channel p-MOSFET is prospected.

CO2 geological sequestration is one of the most promising methods for reducing anthropogenic CO2 emission into the atmosphere. To carry out the technology, it is necessary to evaluate the formation geological condition of storage area for the security and effectiveness. The CO2 reserve capability of formation is mostly connected with reservoir physical property. The CO2 storage security is mostly connected with seal quality of cap rock. This paper takes advantage of logging data material to comprehensively evaluate the seal condition and storage capability from the cap rock condition of the supercritical fluid and the reservoir capacity. It gives an evaluation instance of the slected area.

This paper analysed a cold-formed thin-wall steel-ribbed housing’s internal forces, displacements and the overall stability under different load combinations by the finite element method, the results showed that the structure system could meet the capacity requirements and mitigate the structure weight effectively, save the amount of steel. It also proposed the shoring arrangement of increasing the building overall lateral stiffness by comparative analysis.

combined with the spillway design of Xiaoguo reservoir reinforcement engineering, this paper introduces and researches the whole arrangement of the spillway, the calculation of discharge capacity and water surface line of chute and hydraulic calculation of stilling pool. The related process and results can provide a reference for similar engineering.

As a specific example，this paper introduces the whole arrangement of the spillway of Zuocun reservoir，and explains a specific course of spillway design for small-scale reservoir danger control and reinforcement project from three aspects, the calculation of discharge capacity、water surface profile of chute and hydraulic calculation of stilling pool. The project can provide a reference for similar engineering.

Karl Fischer moisture analysis method is regard as the best way to determine the water content of the substance, which is widely used in industry of petrochemical, food, cosmetic and so on. In order to improve the maneuverability of the method, reducing the costs and improve work efficiency, this paper presents a Karl Fischer moisture virtual analyzer (KFMVA) system, which using STC11F32XE MCU as the core of the system, combined with PC by the LABVIEW serial communication module, realized the data collection, processing, display, storage and print capabilities.

The efficiency of the element removal or addition is of significance for evolutionary structural optimization (ESO) process. The key is to find an appropriate rejection criterion (RC) which allows to assess the contribution of each element to the specified behavior（stress, stiffness, displacement, etc.）of the structure, and to subsequently remove elements with least contribution. This paper proposed a varying elements removal ratio (VERR) method which uses a larger ERR (Element Rejection Ratio) value at early iterations where exist a lot of redundant material, and decreases the value of ERR in the optimal process to lessen the number of elements removed at later iterations. Meanwhile, this paper proposed a strategy for element addition based on stress level and the contribution of elements to the structure in order to decide which elements should be added to the model and the sequence of the element addition. With the proposed VERR and the strategy, the optimization procedure of the structure evolves more quickly and smoothly.

A high accuracy non-contact laser displacement measuring system is developed to obtain the surface deformation of the ice-like material. A speed measurement and positioning system is established for the moving air cushion load. The mechanical properties of the ice-like material and the pressure distribution of air cushion load are measured. Under different air cushion load and different speed, a series of experiments of the deformation of ice-like material are carried out in towing channel which the depth of water is variable. The maximum deformation of ice-like material can be caused when air cushion load moves at critical speed, and the ice-water resonance mechanism of ice-breaking by air cushion is revealed, which provides the basis of ice-breaking for practical air cushion vehicle.

Complex resistivity of soil must be measured using low-frequency power supply to overcome the skin effect, but, because of using higher frequency, the existing conventional complex resistivity meter is not suitable for soil. To this end, with the discrete Fourier transform and spectrum analysis, a measurement system for soil complex resistivity based on LabVIEW virtual instrumentation development platform and PXI data acquisition card was designed and developed. The system can measure the complex resistivity of the soil under low frequency, track the fluctuations of supply frequency automatically using of software synchronization technology, and then automatic adjust the sampling rate to reduce measurement error. The measurements results of the Cole-Cole circuit model of complex resistivity show that the system has a high accuracy.

Rotary Piston Engine is a new kind of rotary engine. To analyze the dynamic character of the valve system, kinematics equations are established using dynamical method. Dynamic response of the valve is studied by calculating the outcome using numerical method.FFT analysis is applied here to analyze the response curve. The result shows that the Valve Train covers the basic need, but the dynamic performance of the system still could be improved.

According to the differential equation of thin elastic vibrating plate and the similarity theory, the similar relationships of corresponding parameters between model and prototype as well as between the ice-like material and the real ice are established. A high accuracy non-contact laser displacement measuring system is developed to obtain the surface deformation of the ice-like material. A speed measurement and positioning system is established for the moving air cushion load. At different moving speed of air cushion load, a series of experiments of the deformation of ice-like material are carried out in towing channel which the depth of water is variable. At critical speed the maximum deformation of ice-like material can be caused, and the theory is derived and analyzed. Research results present the basis of ice-breaking for practical air cushion vehicle (ACV).

The project is a complicated systems engineering. The theory of whole life cycle cost considers roundly each phase of the project such as design. life cycle cost theory is applied to fields of maintenance and reinforcement about existing building structure, modeling with a reinforced concrete frame structure deterioration, it made a research about the influence of maintenance, repair and reinforcement measures to the reliability and deterioration speed of existing structure while analyzing its life cycle cost, considering economic optimization problem so as to select economy and reasonable maintenance scheme from multiple plans.

Applying linear marine hydrodynamics theory, the Kelvin wave source Green function of steady motion in finite depth was decomposed to three parts: array of simple Rankine sources, local distribution and wave part. Both at subcritical and supercritical speed, the singularity of integral function were eliminated by different integral path. The Kelvin source was distributed on the surface of ship by panel method, and the ship pressure distribution and wave pattern of ship in finite depth were calculated. The difference and connection between finite and infinite depth results were compared. It can provide the theoretical arithmetic base of improving the ship seaworthiness, increasing the speed and optimization of ship in river and offshore strip.

In order to validate the theory and select effective operational parameters in practical ice-breaking by air cushion vehicle (ACV), experimental study should be carried on firstly. The relationships of corresponding parameters between ACV model and prototype and between the ice-like material and the real ice are established on the basis of the similarity theory and the differential equation of thin elastic vibrating plate under static or moving load. According to geometric and dynamic similarity between model and prototype, for the conditions of different water depth, ice thickness, mass and velocity of ACV in actual operating mode, the pressure and velocity of ACV model, the elastic modulus and density of ice-like material in model test can be determined, the method of extending the model test results to prototype is proposed.

Considering the efficiency problem of software vulnerability discovering in Linux system, a new software vulnerability discovering in Linux system program with data mining algorithm is proposed in this paper. An improved REL algorithm based on one-dimensional linked list is proposed, and mining on Linux sequence data of system call with REL algorithm, then we do analysis and detection of software vulnerabilities. A model of software vulnerability discovering analysis system with LRE algorithm was designed. Finally, experimental results show the validity of mining on Linux sequence data of system call with REL algorithm in terms of reducing the false alarm rate, and improving the efficiency of software security vulnerability discovering.

Digital image technology is the most effective and important way to communicate and acquire information. Image can be used as a mean or carrier of detecting and transmitting information. The accession of image processing technology solves many defects such as time-consuming, complex operation, low precision which existed in manual statistics and analysis on particles. The basic physical properties of particles include pore, shape, size and other parameters. Computer can be used for a variety of image processing, both to speed up the analysis processing and highlight the information people need at the present.

On the basis of the differential equation governing small flexure of thin elastic vibrating plate, the formula for calculating the phase velocity and group velocity of ice sheet wave propagation under the air cushion load is induced. The minimum of the phase velocity is the critical speed about ice breaking by air cushion vehicle (ACV). If ACV moves at the critical speed, the energy causing the deformation of ice sheet is concentrated constantly, thus the amplitude of the wave is enlarged enough to break the ice by resonance.

Underground mine surveillance can record the situation of coal production site timely and accurately. Because of the poor quality of air, inadequate lighting, lower monitor equipment resolution, surveillance images are blurred. This paper makes full use of the complementary information between surveillance images sequence. And we reconstruct high resolution images by using of maximum a posteriori (MAP) algorithm. Experiment results show that the reconstructed images can reflect the detail of the underground mine surveillance images. Compared with the traditional interpolation results, the reconstructed images avoid jagged effect and overall fuzzy. The PSNR of images are also improved.