WORKPIECE LOCATING AND POST PROCESSING SYSTEMS ON 6-DOF CNC MILLING MACHINE

A conventional non-computerized numerical control （CNC） machine is updated by mounting a six degree-of-free （DOF） parallel mechanism on it, thus obtaining a new CNC one. The structure of this CNC milling machine is introduced, and the workpiece locating system and the post processing system of the cutter location （CL） data file are analyzed. The new machine has advantages of low costs, simple structure, good rigidity, and high precision. It is easy to be transformed and used to process the workpiece with a complex surface.

Development of a Post-Processing Automation Procedure for the GPS-Based Travel Time Data Collection Technique

The travel time data collection method is used to assist the congestion management. The use of traditional sensors (e.g. inductive loops, AVI sensors) or more recent Bluetooth sensors installed on major roads for collecting data is not sufficient because of their limited coverage and expensive costs for installation and maintenance. Application of the Global Positioning Systems (GPS) in travel time and delay data collections is proven to be efficient in terms of accuracy, level of details for the data and required data collection of man-power. While data collection automation is improved by the GPS technique, human errors can easily find their way through the post-processing phase, and therefore data post-processing remains a challenge especially in case of big projects with high amount of data. This paper introduces a stand-alone post-processing tool called GPS Calculator, which provides an easy-to-use environment to carry out data post-processing. This is a Visual Basic application that processes the data files obtained in the field and integrates them into Geographic Information Systems (GIS) for analysis and representation. The results show that this tool obtains similar results to the currently used data post-processing method, reduces the post-processing effort, and also eliminates the need for the second person during the data collection.

A study on fast post-processing massive data of casting numerical simulation on personal computers

When castings become complicated and the demands for precision of numerical simulation become higher,the numerical data of casting numerical simulation become more massive.On a general personal computer,these massive numerical data may probably exceed the capacity of available memory,resulting in failure of rendering.Based on the out-of-core technique,this paper proposes a method to effectively utilize external storage and reduce memory usage dramatically,so as to solve the problem of insufficient memory for massive data rendering on general personal computers.Based on this method,a new postprocessor is developed.It is capable to illustrate filling and solidification processes of casting,as well as thermal stess.The new post-processor also provides fast interaction to simulation results.Theoretical analysis as well as several practical examples prove that the memory usage and loading time of the post-processor are independent of the size of the relevant files,but the proportion of the number of cells on surface.Meanwhile,the speed of rendering and fetching of value from the mouse is appreciable,and the demands of real-time and interaction are satisfied.

Hybrid Post-Processing Procedure for Displacement-Based Plane Elements

In the analysis of high-rise building, traditional displacement-based plane elements are often used to get the in-plane internal forces of the shear walls by stress integration. Limited by the singular problem produced by wall holes and the loss of precision induced by using differential method to derive strains, the displacement-based elements cannot always present accuracy enough for design. In this paper, the hybrid post-processing procedure based on the Hellinger-Reissner variational principle is used for improving the stress precision of two quadrilateral plane elements. In order to find the best stress field, three different forms are assumed for the displacement-based plane elements and with drilling DOF. Numerical results show that by using the proposed method, the accuracy of stress solutions of these two displacement-based plane elements can be improved.

Post-seismic relaxation process and vertical deformation following the 2008 Ms8.0 Wenchuan earthquake, China

The post-seismic horizontal and vertical deformations following the 2008 Ms8.0 Wenchuan earth- quake are inferred from GPS and precise leveling data. The post-seismic relaxation process is measured using GPS data from campaign stations located around the Longmenshan fault, and the derived decay time constant is 12 days. The evolution of the post-seismic vertical deformation is obtained from precise leveling data measured near the surface rupture. The results demonstrate that the hanging wall is uplifting and the foot wall is subsi- ding. The amplitude of the post-seismic deformation is lower than that of the co-seismic deformation. The re- gion with the largest post-seismic displacement is located on the leveling route between Maoxian and Beichuan on the hanging wall.

Effects of Fillerwire Composition along with Different Pre- and Post-Heat Treatment on Mechanical Properties of AISI 4130 Welded by the GTAW Process

This research intends to find out the optimal mechanical properties of AISI 4130 steel welded by the GTAW process. Six test plates were joined by two types of filler wire with similar chemical composition to the base metal, and with lower carbon content and slightly higher alloy elements content compared to the first one. Test plates then exerted three different pre-heat and post-heat treatments on both groups. The three types of heat treatments were alternatively without pre-heat and post-heat, with pre-heat only, and finally with pre-heat and post-heat. Tensile, side bends and impact tests (for weld zone and HAZ) have been conducted. Results show that using low-carbon filler wire along with pre- and post-heat resulted in outstanding mechanical properties.

PREPROCESSING AND POSTPROCESSING SYSTEM FOR FINITE ELEMENT COMPUTATION

This paper discusses some aspects of finite element computation,such as the automatic generation of finite element ,refinement of mesh,process of node density, distribution of load,optimum design and the drawing of stress contour, and describes the developing process of software for a planar 8 node element.

氯乙烯光催化氟化联合合成HFC-152a和HCFC-142b后处理工艺的研究

根据氯乙烯光催化氟化联合合成HFC-152a和HCFC-142b反应产物的特点,设计了工艺成熟、流程合理的后处理工艺,并提出了各工序的技术要点。

PROTOTYPE SURFACE MICRO- PRECISION IN FUSED DEPOSITION MODELING PROCESS

To aim at prototype parts fabricated with fused deposition modeling （FDM） process, the problems how to improve and enhance their surface micro-precision are studied. The producing mechanism of surface roughness is explained with three aspects concretely including the principle error of rapid prototyping （RP） process, the inherent characteristics of FDM process, and some mi- cro-scratches on the surface of the extruded fiber. Based on the micro-characters of section shape of the FDM prototype, a physical model reflecting the outer shape characters is abstracted. With the physical simplified and deduced, the evaluating equations of surface roughness are acquired. According to the FDM sample parts with special design for experimental measurement, the real surface roughness values of different inclined planes are obtained. And the measuring values of surface roughness are compared with the calculation values. Furthermore, the causes of surface roughness deviation between measuring values and calculation values are respectively analyzed and studied. With the references of analytic conclusions, the measuring values of the experimental part surface are revised, and the revised values nearly accord with the calculation values. Based on the influencing principles of FDM process parameters and special post processing of FDM prototype parts, some concrete measures are proposed to reduce the surface roughness of FDM parts, and the applying effects are better.

On the horizontal distribution of algal-bloom in Chaohu Lake and its formation process

Based on the remote sensing images of algae, the present work analyzes the horizontal distribution characteristics of algal blooms in Chaohu Lake, China, which also reveals the frequency of algal blooms under different wind directions. Further, an unstructured-grid, three-dimensional finite-volume coastal ocean model （FVCOM） is applied to investigate the wind-induced currents and the transport pro- cess to explain the reason why algal blooms occur at the detected places. We first deduce the primary distribution of biomass from overlaid satellite images, and explain the formation mechanism by analyzing the pollution sources, and simulating the flow field and transportation process under prevailing wind over Chaohu Lake. And then, we consider the adjustment action of the wind on the corresponding day and develop a two-time scale approach to describe the whole formation process of algae horizontal distribution in Chaohu Lake. That is, on the longer time scale, i.e., during bloom season, prevailing wind determines the primary distribution of biomass by inducing the characteristic flow field; on the shorter time scale, i.e., on the day when bloom occurs, the wind force adjusts the primary distribution of biomass to form the final distribution of algal bloom.

Prediction and Analysis of Post-Treatment of Sustainable Walnut Shell/Co-PES Parts by Laser Sintering

In order to enhance the strength of sustainable walnut shell/Co-PES(WSPC)sintered parts,wax-filtrated posttreatment was carried out.The effects of treating fluid temperature,preheating time and immersion time on the bending strength of WSPC wax-filtrated parts were analyzed by single factor analysis method.To obtain an accurate model for predicting the bending strength of the WSPC wax-filtrated part,the experiments were involved by using Box-Behnken design(BBD).Main parameters,such as treating fluid temperature,preheating time and immersion time,and their interactive effects were analyzed through analysis of variance(ANOVA)and graphical contours.The results demonstrated that all parameters’direct effects were significant to bending strength of the WSPC wax-filtrated part.Its optimum value was 5.0 MPa when the treating fluid temperature of 70°C,preheating time of 50 min,and immersion time of 20 s.The predicted models effectively validated had good predicting accuracy.The WSPC wax-filtrated part using optimal processing parameters was processed by investment casting,and then the metal casting of dimensional stability and smooth surface was obtained.Investment casting was done using WSPC wax-filtrated parts under optimal process parameters and then metal parts with stable structure size and smooth surface can be obtained,which indicates that WSPC material can be used for investment casting.

Development of an automatic post-weld inspection system based on laser vision

In order to overcome the limitations of manual post-weld visual inspection approach, an automated inspection system is developed which uses three-dimensioual laser vision system based on the principle of optical triangulation. The system hardware consists of a modular development kit （MDK）, a computer, an actuating mechanism and so on. In image processing algorithms, extraction accuracy of centric line of laser stripe is the critical factor that determines the system performance. So according to the features of laser stripe image, a novel algorithm is developed to detect the central line of laser stripe fast and accurately. Experiments have demonstrated that this system can be used in various weld features inspection of both butt and fillet types of weld. Compared with traditional manual inspection method, this method has obvious dominance. The three-dimensional reconstruction result shows that this system has high accuracy and reliability.

Modal identification based on Hilbert-Huang Transform of structural response with S VD preprocessing

In recent years, Empirical mode decomposition and Hilbert spectral analysis have been combined to identify system parameters. Singular-Value Decomposition is pro- posed as a signal preprocessing technique of Hilbert-Huang Transform to extract modal parameters for closely spaced modes and low-energy components. The proposed method is applied to a simulated airplane model built in Automatic Dynamic Analysis of Mechanical Systems software. The results demonstrate that the identified modal parameters are in good agreement with the baseline model.

The EVA plastic film for V-process and steel castings by V-process in China

EVA plastic film is the key material for V-process. Through decades of research, special EVA film for V-process has been produced. The film has adequate elongation; its maximum is about 800% in longitudinal direction and 750% in transversal direction. The single width of the film is 2.8 m and the double width is 5.6 m, which is the widest sheet film for V-process in China. Sheets with different thickness ranging from the thickest 0.35 mm to the thinnest 0.08 mm can meet different demands in China. The film can be used not only for V-process of iron castings, but also for the manganese steel railway frog, steel rocking support and side frame castings for train and the steel bridge box for engine truck.

基于PM-POST的先进数控加工中心后置处理系统研究

针对TX1600G复合式镗铣加工中心专用后置处理系统存在的问题,基于PowerMILL软件平台,以TX1600G复合式镗铣加工中心为基础,详细介绍了利用PM-POST软件创建NUM1060m控制器后置处理系统的过程,并成功地对箱体零件进行后置处理,为TX1600G复合式镗铣加工中心专用后置处理系统的开发提供了参考。

基于磁控溅射和电子束蒸发合成Mn-Co-Ni-O薄膜

锰钴镍氧(Mn-Co-Ni-O,MCNO)薄膜因为具有优异的负温度系数特性在近年来受到广泛关注,现采用射频磁控溅射和电子束蒸发相结合的方式,在单抛蓝宝石(Al2O3)衬底上制备MCNO薄膜,并采用一系列表征探讨了后道退火(Post Annealing,PA)温度对所制薄膜的微观结构和光学性质的影响。结果表明,随着PA温度的提高,MCNO膜的晶粒尺寸和间隔均呈现增大趋势。X射线光电子能谱结果表明,Mn3+/Mn4+的比例随着温度的升高而增大。电学和光学特性研究表明,在PA温度为850℃,条件为空气退火1 h得到的MCNO薄膜在温度范围为220~300 K范围内符合VRH模型,TCR系数良好,激活能为0.32 eV,薄膜在红外可见波段具有较高吸收率。

Risk Assessment M ode of Sale-Leaseback——Based on Fuzzy Analytic Hierarchy Process

Sale-leaseback is paid special focus on for its great application in China in recent years.By giving a detailed analysis,an analysis of the features of sale-leaseback and a study of the risks of it are given in this paper.Then a quantitative analysis of commercial real estate sale-leaseback is carried out.The scientific theoretical analysis is provided in this paper for risk assessment in commercial real estate sale-leaseback mode in China.An effective approach is put forward for sale-leaseback project evaluation and prevention of risk.A useful means is given to supervise commerciai real estate sale-leaseback mode for relevant departments and a certain contribution is made to a further sound development of commercial real estate sale-leaseback mode.

Consequence of reinforced SiC particles and post process artificial ageing on microstructure and mechanical properties of friction stir processed AA7075

Friction stir processing and post process artificial ageing was successfully carried out on AA7075 with and without reinforcement of SiC particles producing defect free processed zone with uniform distribution of filler material.Effect of SiC particle reinforcement and artificial ageing times on the microstructural modifications was characterized using optical and electron microscopy,electron backscattered diffraction and X-Ray diffraction.Hardness,impact and wear tests were carried out to investigate mechanical behaviour before and after processing.Reinforcement of SiC particles during FSP and subsequent age hardening treatment brought about nearly twofold increase in hardness and impact toughness values by the combined effect of grain refinement,Zener pinning,dispersion strengthening and precipitation hardening.Significant improvement in wear resistance in terms of wear loss was also observed after processing compared to the reference material AA7075-T6.Fractured surface of post FSP age hardened AA7075 alloy exhibited features of ductile fracture during Charpy impact test.

基于AHP-熵权TOPSIS法的绿色商业建筑使用效果评估研究

近年来我国绿色建筑正逐步向高质量发展的阶段迈进,但运营阶段作为绿色建筑全生命周期中的重要一环却被忽视,绿色建筑的实际运行效果也不被人们所感知,因此亟需一套合理且具有针对性的绿色建筑运营评价体系来判定绿色建筑的运行效果情况,以促进绿色建筑的高质量发展。结合使用后评价方法的对比分析,选用AHP层次分析法和熵权-TOPSIS法构建一套适用于绿色商业建筑的使用效果评估模型,并选取5个湖南省绿色商业建筑进行案例调研,从指标体系筛选、不可感知度调查、权重计算和综合测评结果等方面进行比较分析,根据商业建筑运行中的关键影响要素,从绿色商业建筑设计改进策略、绿色技术应用优化、绿色建筑评价标准优化3个方面提出建议。

The Application of Air-flow to the Technological Process of Chemical Fiber

The air-flow’s states and ways acted on the technological process of chemical fiber are summed up, which includes chip drying, spinning quenching as well as airjet texturing (air texturing, tangling texturing and bulked continuous filament (BCF)),and the effect of air-flow on the process and quality of chemical fiber is studied,and the action of mechanics and heat on the bulked continuous filament are calculated.