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With the rail vehicle industry development and increasing request to the riding comfort, to reduce the structure vibration and noise caused by the gearbox is increasingly valued. Multibody dynamics method is proved to be very effective to structure optimization for noise control in gearbox design process. This paper aims to find an optimization way for the gearbox structure to increase the structure noise performance. Initially gear shafts and the casing were discretized using the finite element method, subsequently the multi-flexible body of low floor gearbox was established in the SIMPACK which considering the time-varying mesh stiffness and backlash, bearings were modelled via radial, axial and rotational stiffness elements, then the multi-flexible body dynamic response were analyzed and the structure noise was predicted. Finally, optimization schemes, in terms of gear modification and structure improvement, were proposed to improve the structure noise performance.

A new method to infill the opening in the precast fabricated concrete shear wall was applied in China. In this paper, three geometrically identical precast fabricated shear wall specimens were constructed and tested under constant axial load and quasi-static cyclic lateral loading. The only difference among three specimens was the methods to infill the opening in the middle, the methods were respectively integration infill, masonry infill and without infill. The hysteretic curves, the skeleton curves, the failure process, the strain variation of reinforcement, the stiffness, the ductility and energy-dissipating capacity were obtained. The results and analysis showed that integration shear wall owns good seismic performance. Its bearing capacity, stiffness, energy-dissipating capacity are excellent while ductility is relatively poor. Masonry infilled wall and wall without infill also own good seismic performance.

Electrical discharge grinding is used to machine polycrystalline diamond layer of cutting tools, which can effectively drill composite/titanium stacks in modern aircraft frames. In the machine, an electrode wheel is rotated to accelerate debris flushing to quickly recover the dielectric fluid between a spark gap. The aim of this study was to investigate the effect of the wheel speed on polycrystalline diamond removal rate for high erosion efficiency. Multiple wheel speeds were applied in a electrical discharge grinding machine under various pulse on-times and the volumetric removal rates were calculated by the precise position feedback of this machine over the time, which was obtained by the electrical waveform of discharges. The experimental results show that the removal rate increases with the wheel speed up to a limit at the low range and then declines at the high range. This indicates that the wheel speed needs to be optimized for high erosion efficiency under various discharge conditions such as different materials and pulse on-times.

The prediction of deformation of foundation pit’s supporting structure is the basis of construction control of deep foundation pit. Meanwhile, it is vital to the safe excavation of foundation pit. In the work, the 1st project of Huaqiao in Jiantao Square of Kunshan City is chosen. Besides, model of combination based on entropy method is built to predict the displacement of circle beam with BP neural network and ARMA time series model. Finally, the analysis shows that combination models improve overall prediction on the premise of better predicting accuracy. Thus, it is of practical value.

The electrical discharge grinding method is widely used to machine polycrystalline diamond tools because diamond is the hardest material and the traditional abrasive grinding method leads to high tool wear rate. The aim of this study was to find a method to precisely measure the individual diamond crate morphology during the electrical discharge process. A 3D microscopy with the focus-variation technique was chosen to obtain the stereolithography file of the polycrystalline diamond craters. The measurements were shown that the polycrystalline diamond crater morphology is more complex than that of normal tungsten carbide material. This finding can help build more accurate model of polycrystalline crater formation during electrical discharge process.

In order to grasp the braking effect of the portal crane after the installation of auxiliary wind safety device, the braking process of real harbor crane with dual-stage windproof braking system exposed to fluctuating wind is simulated. The effect on the crane braking performance of braking device response lag and artificially lowering working braking force is also analyzed. It is demonstrated that the dual-stage brake system is superior to the single and could improve the windproof ability when working braking force decline.

This paper introduces the topology and working principle of modular multilevel converter, simplifying its equivalent circuit before obtaining virtual equipotential. On the ground of the theoretical model of equivalent circuit, MMC-HVDC could adapt the same control strategy as the traditional method. So, on the platform of PSCAD/EMTDC, an eleven level MMC Dual-infeed HVDC system is established and nearest level modulation is adopted as its control strategy to sort voltage sharing of the modules. Experimental results prove the validity of the proposed model.

The paper introduces the way of solid modeling and wire frame modeling, described modeling ways from drawing the general outline of the form, to using the general model to make out the general modeling of form, to making the whole effect of the animation by combining with concrete examples which are pf rapid and convenient application value in promoting design speed, enriching expression effect (surface modeling), optimizing design process. It is beneficial to play the design wisdom, give consideration to both economic and social benefits. Its modeling is easy to meet consumer demand for fresh and exaggerated things, and helps to clear the market demand, good commodity modeling and its industrialization prospect.

The study of tracking algorithm of moving objects is a key technique in computer vision; therefore, the work done by this thesis has important theoretical significance and wide practical value. An algorithm based on the improved three-frame-differencing is introduced in this paper. Firstly, three continuous edge images are obtained by edge extract from three continuous images, then, the motion information is detected with three-frame-differencing, finally, the target is extracted by threshold segmentation and morphology. The method is simple in calculation. The experimental results show that the strong robustness and can accurately detect the moving target. In addition, using the algorithm based on the characteristics of the objects can clearly record the object’s trajectory. Experiments show that the algorithm is effective and feasible in the motion object detection.

Leakage of the heat distribution pipeline will seriously affect the safety of residents and cause economic losses. This paper presents the transient electromagnetic method (TEM) for detecting the corrosion of buried heat distribution pipeline, which mainly introduced the principle of the TEM to detect the pipeline and the general detection method. Combining with an instance of corrosion detection of buried heat distribution pipeline in a certain street in China Hohhot, the detection results were analyzed and the feasibility of this method was proved through excavation. The results show that the TEM can detect the uniform corrosion distribution of buried metal pipeline and it’s effective and practical for detecting the buried heat distribution pipeline. The TEM could provide a new method for guaranteeing the safe operation of the heat distribution pipeline.

Starting from constitution of design symbols, this article analyzes the constitution forms before sending and receiving messages, the decomposed information carriers of senders and receivers, the coding rules of sending messages formulated by senders and decoding rules of receiving messages by receivers, thus concludes three basic rules, namely, regular、irregular and mixed type of understanding. And the design symbol reveals the distribution and enjoyment of culture. Without social relationships and communication of individuals, there will be no symbols and transmission、the systematic integration of various human design symbols as well as the approaches of the accumulation of collective experience and the pass of behaviors of individuals.

The medium with gradient change of acoustic impedance is a new acoustic structure which developed from multiple layer structures. In this paper, the inclusion is introduced and a new set of equations is developed. It can obtain better acoustic properties based on the medium with gradient change of acoustic impedance. Theoretical formulation has been systematically addressed which demonstrates how the idea of utilizing this method. The sound reflection and absorption coefficients were obtained. At last, the validity and the correctness of this method are assessed by simulations. The results show that appropriate design of parameters of the medium can improve underwater acoustic properties.

With the improving of the electricity users requirements for power quality, traditional electricity pricing model cant meet the needs of users. This thesis first carries on the analysis of electricity cost factors, and then establishes the cost model of electricity generation companies and electricity supply companies. The formulation of electricity price should consider electricity users, electricity generation companies, electricity supply companies and state taxes. And each factor should bear responsibility of electricity price's formulation based on social fair burden coefficient. So the thesis establishes an electricity price's model based on above theory.

In order to make the design of modern complex software support the multi-disciplinary optimization,realize its solving function,and confirm its comprehensive optimum scheme,We put forward a modeling method,which is combining the Freeform with surface design. Considered the characteristics of modern software design,we analyzed the important role that modern software played in the modeling process,studied the application process of modeling that combining freeform with the surface design.,and did the application of virtual design,for example,combined the technology of virtual claywith force feedback into the virtual design. Put the above method into the product design,and we confirmed that this technology can add or reduce the soil in accordance with the different demands, and is an effective method to solve the complex problems in the modeling process.

This paper introduces the design selection and implementation program of the supporting structure of no-load side-direction excavated CFG composite foundation, in the case of the foundation pit excavation of stage bin of the Jinan Cultural Arts Center Grand Theater. The monitoring data shows that the lateral reinforcement effect of no-load CFG composite foundation can not be discounted. Based on composite foundation and rock mechanics, consider the no-load CFG composite foundation as the composite soil, build its mechanics index system and calculation method. Calculating and analyzing of the supporting structure that placing a row of anchor cable in cantilever double-row pile and double-row pile by means of applying composite soil parameters and using the pit design software and numerical simulation, and comparing the result with actual monitoring data. Therefore, we can further prove that lateral reinforcement effect on soils by considering CFG composite foundation.

the developing trend of upholstered furniture in years will be studied through the analysis of furniture aesthetic performance, combining personal designing case, applied human engineering, marketing, design methodology, graphics, statistics, Perceptive and cognitive principle in psychology in this thesis. Reference and relatively abundant, comprehensive support can be provided for designers through the value theory of aesthetic subject and object, which will improve the marketing competitiveness of independent research and development of China. This thesis also aims to light the law of upholstered furniture development. Such laws can explain how to adjust to the popular consumer demand under the current industry mode.

With the improvement of the power users requirements for power quality, traditional electricity pricing model cannot meet the needs of the users. At first, a concept of power user satisfaction was proposed, and the mathematical model of different categories of power user satisfaction was established. On the basis of comprehensive analysis of various kinds of power load characteristics, the mathematical model of the relationship between power and electricity price was given, and the simulation analysis shows that in the case of certain electricity price, power supply returns will be increased considering user satisfaction. Finally, an electricity price design mathematical model considering both user satisfaction and power supply enterprise's returns was established, and the model will provide certain theoretical basis to formulate a reasonable electricity price.

rapid and efficient product design nowadays is one of the crucial researching fields of design methodology. The invention of virtual clay technology FreeForm is absolute a beneficial supplement to computer-aided design. Therefore, this thesis finds its value in enriching the modeling method in computer-aided design, especially in the perspective of integration between surface and fast modeling and production, a quick response to the demand and change in market.

Based on many inquiries, analyses and researches, alternate measures of science and social science are taken in this paper, considering series of geo-environmental effect, and the harmfulness of geological effects in Chongqing main city are analysed. The basic counter measures and managing measures are suggested to treat geo-environmental problems in Chongqing main city so that a long-term plan of city-developing and the objective of a struggle based on real situation are set up. The analytic results are helpful to solve the serious geo-environmental effects, and push forward the study of urban geo-environmental problems of underground engineering in Chongqing.

The maximum power tracking and Grid-connected is the urgent need to solve the problem which exists in the grid-connected PV system. This article expounds on the maximum power point tracking and grid inverter control strategy. It puts forward the control strategy of researching maximum power point tracking, which is effective in improving solar panels convert solar energy into energy. With the development of photovoltaic technology, requirements of photovoltaic grid control strategy are getting higher and higher. This article examines adaptive disturbance observed method integrated control combined BOOST boosted circuit, in order to achieve the maximum power point tracking for photovoltaic panels .The photovoltaic inverter control structure is to meet the photovoltaic conversion efficiency and power quality of the main technical indicators. It put to use double topology and feed forward decoupling control strategy, which provides protection for the flexible grid.

Oil pump cover, as a part of the oil pump, is generally formed by adopting aluminum die casting molding, and required for good internal and external quality. In order to improve the oil pump cover forming quality, the paper first simulates the thermal equilibrium of die-casting mold in the forming process by finite element analysis, and obtains the temperature curves when mold works for 10 consecutive cycles, and determines that the thermal equilibrium temperature of die-casting mold is 260 °C. And then, based on the simulation results of filling and solidification in the forming process by ProCAST software, the shrinkage and cavity appear in the larger wall thickness of the casting. Meanwhile, by simulating the die-casting processes of the oil pump at different pouring temperatures, there are the least of shrinkage and cavity when the pouring temperature setting 640 °C. The results show that: it can take some methods to achieve the progressive solidification, and can reduce or eliminate the possible shrinkage and cavity, such as shortening the distance between sprue, runner and inner runner and die casting to reduce the casting heat loss, or adding cooling system to accelerate the cooling rate in the larger wall thickness of the casting. This analysis provides theoretical basis for the actual casting production of oil pump covers.

The popularization of mobile intelligent devices has greatly enriches the function of intelligent district. The intelligent district system which is IP-centric and provides multimedia services such as voice, fax, data, and images has becomes focus of the field. In this article, a mobile intelligent district value-added service platform based on SIP and Web Service is introduced, with the intelligent terminal devices, district residents can get customized service information on their own initiative, and they can communicate with the terminals in the district. Based on the implementation of the platform, information pushing function, weather forecast service and SIP message service are tested, and the result shows the feasibility of the platform, which can be used to satisfy the growing needs of district residents.

The key factors involved in the train derailment on bridges or lines have been discussed in this paper. Also the statistics of derailment accidents with an upward trend occurred in recent years, all over the world, are listed. Analysis of the reasons for train derailment, geometric criterion and mechanical mechanism of train derailment are discussed. Then the authors make an analysis of difference of train derailment between bridges and lines from five aspects. The conclusions have been drawn from the comparative analysis of train derailment involved in lateral stiffness, derailment time history, flow field, motion equation and resonance. There is no characteristic of time history for a certain distance on line derailment. And the mechanical characteristics of vehicle-bridge system are more complicated than the vehicle-line system under wind loads.

The research of this paper was derived from the small autonomous underwater vehicle (AUV)Raider well performed in the 15th International Underwater Vehicle Competition (IAUVC),San Diego. In order to improve the performance of underwater vehicle, the control system of performance motion played an important role on autonomous underwater vehicles stable motion, and the whole control system of AUV is the main point. Firstly, based on the motion equations of six degrees of freedom, the paper simplified the dynamical model reasonably in allusion; Due to the speed of Raider to find the target was very low, this paper considered the speed was approximately zero and only considered the vertical motion. Therefore, this paper established the vertical hydrodynamic model of Raider, obtaining the transfer equation of vertical motion. Through the experiment and Matlab/Simulink simulation, this paper got the actual depth of the step response curve and simulation curve, and verified the validity of the vertical hydrodynamic model and the correlation coefficient.

This paper is concerned with the crashworthiness design of the front rail on a vehicle chassis frame structure considering uncertain crash directions. The front rail, as a typical thin-walled structure, is sensitive to the loading direction for crashworthiness requirements. Multi-step multi-domain optimization method was applied to obtain a new single-layered front rail (SFR) which has better adaptability to crash loading directions. To further improve the front rail crashworthiness, a two-layered front rail (TFR) is proposed. Response surface method is conducted to pursue the optimal thickness pair of the two-layered front rail. Numerical simulations are carried out with Altair/Hypermesh and LS-DYNA to compare the crashworthiness performances of the standard rectangle front rail, SFR and TFR. The results show that TFR keeps the same adaptability of loading directions as SFR meanwhile it can absorb more crash energy during front angle impacts.

First presents a set of high order partial differential equations for elastic rectangular thick plate base on Mindlin theory. The high order partial differential equations were transformed to linear equations by the double finite integral transform method, and then arrives at the theoretical solution of elastic rectangular thick plate with four edges completely clamped support. Only the basic elasticity equations of the thick plate were used and it was not needed to first select the deformation function arbitrarily. Therefore, the solution in the paper is more reasonable. In order to proof the correction of formulations, the numerical results are also presented to comparing with that of the other references.

The capability-oriented requirements elicitation is an emerging research topic of requirements engineering, especially for complex system such as the C4ISR system. One of the problems is that the capability requirements are usually articulated in natural languages and need to be formally specified to support enterprise architecture analysis. The paper proposes a framework for modeling the domain requirements of C4ISR capabilities and suggests an extended UML modeling technique. As the modeling framework accords with the standard DoD Architecture Framework, the proposed method may populate C4ISR architectural analysis.

“5.12 Wenchuan earthquake”triggered floods, landslide, collapse and secondary geological disaster, trigger a new soil and water loss, having the significant influence to the local river water quality.This article through the statistical analysis of minjiang river and jiangyou wenchuan, beichuan station 2006 ~ 2011 water conditions material, discussing the before and after the earthquake disaster areas of river water quality change characteristics. The results showed From ammonia nitrogen source analysis, urban sewage and industrial waste water, agricultural non-point source pollution and earthquake that triggered the new soil and water loss is the main pollution source. Based on the hydrological site total hardness concentration prediction, we can find wenchuan earthquake disaster area total hardness concentration significantly increase trend.

This article have reviewed the preparation processes, flow path and methods of today's high-performance mesophase asphalt-based carbon fiber, and illustrated the advantages of preparation of high performance asphalt-based carbon fiber. Besides, today's main methods of preparation of asphalt-based carbon fiber have been found, and the key problems of preparation of high performance carbon fiber have been figured out.It is very complex and difficult to control accurately. Preparation of mesophase asphalt-based carbon fiber is mainly reflected in the following points: (1) The selection of asphalt; (2) The quality of the spinning; (3) The effect of oxidation treatment; (4) The temperature during carbonization and graphitization process.

Fissure is one of the most important characteristics in expansive soil. It’s an important factor affecting slope stability in the expansive soil area. With the study of expansive soils typical channel slope fissured characters in the South-to-North Water Diversion Project, different impaction on slope stability such as location and inclination of the fissure are analyzed. By using the limit equilibrium method, the stability of expansive soil slope is analyzed; the most adverse condition of expansive soil slope is concluded. Then anti-slippery pile reinforcement in expansive soil channel slope is studied by using finite difference method. The research is of great significance to the construction and reinforcement of expansive soil slopes in South-to-North Water Diversion Project.

Sandwich composite is a new structure of acoustic stealth structure, implementing both loading and acoustic stealth. Micro-fillings can improve the sandwich absorption coefficient. The influence parameters are studied by absorption theories analysis of sandwich structure. The absorption and reflection coefficient in different categories, size and layers of fillings are analyzed by pulse tube experiments. The results shows that the first absorption peak moves to low frequency by adding fillings, the peak frequency are lower when the fillings size increase, and the absorption coefficient are higher when the thickness of sandwich layers are closed.

Image, due to the impact of such as blurring, distortion, noise, etc., will cause a reduction in image quality and the formation of the degradation of the digital image. The using of some kind of a priori knowledge use the least squares method to be filtered, so that the original image and its recovery minimum mean square error between the two images. This can get a better recovery image.

According to the present situation that China's construction site safety supervision of the development toward informatization, this essay put forward a kind of construction site safety supervisory system based on the internet of things through the introduction of wireless network. At first, combined with the requirements of government and industry, we have analyses the requirements of building construction site for safety supervision. Then combined with the difference between architecture construction site and industrial production safety supervision, referring to the existing industrial video safety supervision system, we put forward the structure of the construction site safety system based on the internet of things. At last, we have also analyses several problems about the contracture of network nodes which should be valued. Wireless network can be better adapted to the changing characteristics of construction site safety supervisory operation, and this will promote effectively the development of safety supervision toward the direction of informationization.

“5.12 Wenchuan earthquake”triggered floods, landslide, collapse and secondary geological disaster, trigger a new soil and water loss, having the significant influence to the local river water quality.This article through the statistical analysis of minjiang river and jiangyou wenchuan, beichuan station 2006 ~ 2011 water conditions material, discussing the before and after the earthquake disaster areas of river water quality change characteristics. The results showed that the affected areas of ammonia nitrogen content after the earthquake are more than before the earthquake content .The fluoride content before earthquake overtop that after earthquake in Wenchuan water source .The total hardness of water quality presents upward trend in disaster area after earthquake, and the total hardness of water quality in 2010 and 2011 is greater then that before earthquake. The total iron content is not affected by the earthquake, before and after the earthquake did not appear obvious difference.

The concept and characteristic of virtual product development technology are introduced,and the four stages of starting stage,development stage, prosperous stage and future development stage show that virtual product development technology uses computer complete the whole process of product development ,and is a reappearance in virtual environment of real process of design and manufacture of product, a integration of virtual computer technology combined with modern designing method ,which explain that Pro/E MasterCAM can realize the value of product virtual developmen.Its advantages are also analyzed ,as well as its development tendency

The wind load on large cranes with great windward areas cannot be ignored. The simulation of wind field is to determine the accurate wind force acting on different parts of cranes and serves as the basis of the windproof design. Taking 300t shipbuliding gantry crane as the study object, this paper uses computational fluid dynamics, calculates the mechanical response of cranes by FLUENT, obtains the graphs of pressure, streamline, force distribution of cranes under different wind loads. Through the result analysis, dangerous force position is pointed out. And the ideas of structural methods to improve the windproof ability of cranes are also proposed.

Adhesively bonding technology is used increasingly by the automotive and aerospace industries. The design of reverse-bent joint is effective way for improving the bonded joint performance. The influence of preformed angle on the stress distribution of the adhesive-adherend interface is studied in this paper using finite element analysis (FEA). By comparing the results of the FEA for reverse-bent joints with different preformed angle, it can be seen that the preformed angle not only have significant influence on the stress distribution of overlap section, but also changes stress concentration at the spew fillet of bonded joint. The results also indicate that there is a best value of preformed angle in which the reverse-bent bonded joint has the best performance.

To analyze the second plastic hinge of high bridge pier formed in the earthquake and study the pier seismic performance, this paper takes the Kunming Slope Railway Bridge as an example. The simulation model was built by the elastic-plastic finite element ANSYS software. The buckling load of piers was calculated by buckling analysis capabilities of ANSYS software, a small enough initial offset given to the model, then the buckling load of piers put into the model. The deformation of non-linear model under the loads was calculated, the process was recorded that the reinforced concrete bridge piers initially yielding on the cross-section, continuously rotating around the neutral axis, and finally forming the eventually plastic hinges in certain parts of pier. The location of the plastic hinges can be inferred by final data of analysis software. By analyzing the calculated results, the seismic performance of the second plastic hinge in high bridge is studied.

According to the pseudo static tests on a two-storey and single-span concrete frame made with recycled aggregates, the failure pattern, hysteresis loop curves, displacement ductility of the recycled aggregate concrete frame are investigated. The time histories of loads and displacements are decomposed to four different levels by using the wavelet packet transform. Based on the decomposition coefficients on the 4th level, a seismic damage index is developed and presented in this paper. The cumulative damage process of this recycled aggregate concrete frame under low reverse cyclic loading is also analyzed by using this damage index. The experiment results clearly indicate that recycled aggregate concrete frames have excellent seismic behaviors. The damage index given in this paper can accurately and effectively reflect the severity of damage for structures under different loading states.

High pressure die casting is a high volume component manufacturing process which is used extensively in many aspects. There are many factors affecting the quality of die-casting die. In this paper, the CAE simulations of filling and solidification processes for die-casting are studied. Numerical analyses are presented for two practical die-casting parts using HZ CAE software. The temperature distributions and filling states in solidification and filling process are presented. Then the deficiencies of the part are predicted. Based on the analyzing results, the structures of the two dies are optimized and longer die service life and high-quality castings are obtained. It is proved that CAE simulation results can offer a helpful reference for die-casting die design.

The composting of sewage sludge and maize straw was investigated in forced-aeration composting systems at aeration rates of 0.28, 0.56 and 0.83 l min-1kg-1organic matter, corresponding to pile A, pile B and pile C. The composting temperature in three piles met the hygienic safety criterion, and final electrical conductivity did not exceed the limit value of 3000 μS cm-1. The final NH4+-N content in pile C exceeded the limit value of 400 mg kg-1. The final NO3--N content, cation exchange capacity and germination index in pile B were superior to those in pile A and pile C.

Focusing on the disadvantages of recent researches for roll planning that seldom consider the warm-up part and solution efficiency is low, in this paper, a parallel planning model and an improved ant colony algorithm were proposed to solve the problem. Firstly, the model considering constraints of both warm-up part and staple one was designed; Secondly, the improved ant colony algorithm was proposed where the slab cluster was used to decrease the searching scope and the local optimization to improve the efficiency of pheromone accumulation. Finally, with production data from hot strip mill, we proof the method can get the best results by comparing with other two ant colony algorithms.

Transparent-component-decimation (TCD) method may simplify the aperiodic sequences to the simplest form and one can obtain the transmissive characteristics without complicated calculations. Applying this method to the Family A of Generalized Thue-Morse [FAGTM(n)] aperiodic superlattices, we obtain directly the formulas of the transmission coefficients at the central wavelength. The results are in accord with the previous published results. It shows that the TCD method can be used to study optical transmission normally through aperiodic multilayers directly and exactly and has bright future.

The measurement method and apparatus of cutting force by high speed milling is introduced. The high speed milling force of wrought aluminum alloy is measured and analyzed through separately examining the influences of various factors, such as cutting speed, cutting depth, milling width, feed per cutting tooth, down or up milling, cooling and lubricating. The results match with outcomes from other’s tests and the theory of metal cutting, and are close to the calculated force values, so that the test can be regarded as positive. It is pointed out that high cutting speed, little cutting depth, properly great working engagement and feed per tooth, high feed rate, down milling and efficient cooling and lubricating should be used to reduce cutting force and deformation, to improve milling accuracy and efficiency, which can be helpful to the spread applications of High Speed Machining.

—This study investigates the upstream of the juncture flows generated by the circular cross section cylindrical body mounted on a flat plate using PIV (Particle Image Velocimetry) technique. The flow structure of laminar horseshoe vortex and a topological insight into the flow pattern of the vortex system were observed. Vortex structures for ReD (Diameter Reynolds number) 1600, 2000, 2400 and 3500 are predicted and discussed in detail. Experiments were conducted to investigate the structure of steady and periodic horseshoe vortex, the effect of Diameter Reynolds number, location of horseshoe vortex core and its variation with the change in Diameter Reynolds number and the location and nature of the saddle point located most upstream of the leading edge of the cylinder. The results revealed that (a) two different flow regimes were observed corresponding to four Reynolds number ranges; (b) the upstream vortex systems approach closer to the cylinder whereas the distance of saddle point located upstream of the leading edge of the cylinder moves away from the wall when the Reynolds number increases.

Today, the inheritance and protection of national culture become increasingly prominent. The findings can be seen that worship plays an important role in Wa nationality through the analysis of Cow Head and Wooden Drum in Wa’s totem worship. Combing with the design of specific cases and Wa’s totem worship, at the same time, extracted the national elements, furniture product design have been carried out. According to the aesthetic demand modern people and human body size scale, the design started which is not only good to realize national culture inheritance and protection, but also will push modern furniture design into the market. It is a good way to inherent and protect national culture, meanwhile, making a profit and reward.

For making the conceptual design process optimization, achieve its various function demand, and confirm the optimal proposal. Contra pose the shortage of conceptual design process, combine the basic national conditions in china, we put forward the basic definition of the conceptual design. Firstly we discussed the basic content and basic step of the conceptual design, secondly, we analyzed demand design, function design, principle design and conceptual design according to designing weapon cupboard for the armed forces department in swallow village located in Hefeng country. We get the superiority of the conceptual design, Benefit designers to use their talents, benefit the innovative design, Stimulate the product design standardization and formulation, benefit product design sustainable and rapid development.

The exact bending solutions of moderately thick rectangular plates with two opposite sides simply supported are derived based on the symplectic geometry method. The basic equations for the plates are transferred into Hamilton canonical equations. Then the whole state variables are separated. According to the method of eigenfunction expansion in the symplectic geometry, the exact bending solutions of the plates are obtained. Since only the basic elasticity equations of the plates are used and there is no need to select the deformation functions arbitrarily, the approach utilized is completely reasonable.

Perimeter protection is an important physical protection approach for buildings and infrastructures, which is also regarded as the first line of protection. Vehicle borne improvised explosive devices (VBIED) have been recognized as a major design threat by many government agencies for years, since they have been so extensively used in past terrorist attacks against critical buildings and infrastructures. Preventing unauthorized vehicles from approaching a protected area with vehicle barriers installed in perimeter of the buildings and infrastructures would consequently reduce blast and debris threats. The history of test certification standard for vehicle barriers is briefly reviewed. The research achievements on anti-ram bollards, one type of vehicle barriers, in the fields of crash test, numerical simulation, and design theory are presented. The remaining problems and deficiencies of the research are pointed out and the corresponding proposals are put forward. Finally, some further research works on anti-ram bollards are proposed.

Asphalt aging is inevitable to the asphalt pavement performance, which will lead asphalt to hardening gradually and becoming brittle. Therefore, aging progress shortens the life of asphalt, but the study on polymer asphalt improves the phenomenon. The present situation on aging of polymer modified asphalt is summarized and the aging mechanism of modified asphalts is analyzed in the paper. Otherwise, the research progress at home and abroad on the aging properties of modified asphalt is introduced by a series of characterization techniques, which include mechanics technique, rheology technique, FTIR, GPC and so on