Rapid Modeling of an Excavator Working Device Based on the Secondary Development of Pro/E

In order to shorten the design cycle of the excavator working device, we have proposed a rapid modeling method for the excavator working device which uses parameters. Based on the Pro/toolkit, which is secondary development tool of Pro/E4.0,and combined with Vs C＋＋2005 programming software. It developed a flexible set of MFC visualization-friendly interfaces. Users can enter data in the visual interface according to their needs and it will generate a new part model quickly. So it improves the design quality, shortens the design cycle, and makes the cost lower significantly.

基于ProE的联合收割机二级齿轮减速器仿真分析

针对联合收割机二级齿轮减速器总体结构进行了设计,基于Pro/E建立了二级齿轮减速器模型并完成了产品的装配,最后利用Pro/E Mechanism仿真模块对所设计产品进行了运动仿真。结果表明:模型满足设计需求,具有较好的稳定性,对二级齿轮减速器进一步的优化设计具有一定参考作用。

基于FTA和Pro-model的医院手术室流程管理问题分析

从定性和定量两方面分析了目标医院现有手术室的流程。首先,通过现场调研获得医院手术流程数据,并采用Minitab进行处理;其次,利用故障树分析法(Fault Tree Analysis,FTA),在定性方面分析现有流程的问题;最后,对现有流程进行Pro-model仿真建模,得到流程各节点运行效果,又从定量方面得到了流程的相关优化指标。

Parameterized Designing of Gears' Three-dimensional Model Based on Pro/E

This paper took Pro/ENGINEER wildfire2.0 as the development environment and realized the involute helical gears’three-dimensional model parameterized designing which made use of the parameter and relation function of Pro/E.This paper also provided a method of editing the equation of the tooth curve,and it can ensure the high precision of the involute helical gear model.It developed the man-machine interactive parameterized designing interface making use of the secondary development function offered by Pro/TOOLKIT.The users can revise the involute helical gear easily by this man-machine interactive.It de- tailedly introduced the method of designing the man-machine interactive interface Using Pro/TOOLKIT and Visual C++.When the users input correlation parameters according to the prompt of the man-machine interactive interface,the three-dimensional model of the involute helical gear is auto-generated.This method simplified the product design process,shortened the period of de- veloping and improved the design efficiency of the gear greatly.

Animal models of hepatitis E infection: Advances and challenges

Hepatitis E virus(HEV)is one of the leading causes of acute viral hepatitis worldwide.Although most of HEV infections are asymptomatic,some patients will develop the symptoms,especially pregnant women,the elderly,and patients with preexisting liver diseases,who often experience anorexia,nausea,vom-iting,malaise,abdominal pain,and jaundice.HEV infection may become chronic in immunosuppressed individuals.In addition,HEV infection can also cause several extrahepatic manifestations.HEV exists in a wide range of hosts in nature and can be transmitted across species.Hence,animals susceptible to HEV can be used as models.The establishment of animal models is of great significance for studying HEV transmission,clinical symptoms,extrahepatic manifestations,and therapeutic strategies,which will help us understand the pathogenesis,prevention,and treatment of hepatitis E.This review summarized the animal models of HEV,including pigs,monkeys,rabbits,mice,rats,and other animals.For each animal species,we provided a concise summary of the HEV genotypes that they can be infected with,the cross-species transmission pathways,as well as their role in studying extrahepatic manifestations,prevention,and treatment of HEV infection.The advantages and disadvantages of these animal models were also emphasized.This review offers new perspectives to enhance the current understanding of the research landscape surrounding HEV animal models.

基于Pro/E的摄像机前盖注塑模具设计

本文通过对摄像机前盖的用途及所使用材料的成型工艺性的分析,利用Pro/E软件实现摄像机前盖注塑模具设计的整个过程。本模具设计内容包括成型方法及模具的选择,型腔数量的确定,型腔的排列,分型面的选择,浇注系统的设计,型芯、型腔尺寸设计,导向、定位机构设计,滑块侧抽芯机构设计,推出机构设计及冷却系统设计。

Prediction model for hepatitis B e antigen seroconversion in chronic hepatitis B with peginterferon-alfa treated based on a responseguided therapy strategy

BACKGROUND Models for predicting hepatitis B e antigen(HBeAg)seroconversion in patients with HBeAg-positive chronic hepatitis B(CHB)after nucleos(t)ide analog treatment are rare.AIM To establish a simple scoring model based on a response-guided therapy(RGT)strategy for predicting HBeAg seroconversion and hepatitis B surface antigen(HBsAg)clearance.METHODS In this study,75 previously treated patients with HBeAg-positive CHB underwent a 52-week peginterferon-alfa(PEG-IFNα)treatment and a 24-wk follow-up.Logistic regression analysis was used to assess parameters at baseline,week 12,and week 24 to predict HBeAg seroconversion at 24 wk post-treatment.The two best predictors at each time point were used to establish a prediction model for PEG-IFNαtherapy efficacy.Parameters at each time point that met the corresponding optimal cutoff thresholds were scored as 1 or 0.RESULTS The two most meaningful predictors were HBsAg≤1000 IU/mL and HBeAg≤3 S/CO at baseline,HBsAg≤600 IU/mL and HBeAg≤3 S/CO at week 12,and HBsAg≤300 IU/mL and HBeAg≤2 S/CO at week 24.With a total score of 0 vs 2 at baseline,week 12,and week 24,the response rates were 23.8%,15.2%,and 11.1%vs 81.8%,80.0%,and 82.4%,respectively,and the HBsAg clearance rates were 2.4%,3.0%,and 0.0%,vs 54.5%,40.0%,and 41.2%,respectively.CONCLUSION We successfully established a predictive model and diagnosis-treatment process using the RGT strategy to predict HBeAg and HBsAg seroconversion in patients with HBeAg-positive CHB undergoing PEG-IFNαtherapy.

Evaluation of the Effects of Cypermethrin on Female Reproductive Function by Using Rabbit Model and of the Protective Role of Chinese Propolis

The prophylactic effects of Chinese propolis against cypermethrin toxicity were evaluated by performing ovary and uterus histopathology, as well as by characterizing ovarian function, embryos, and litters. Cypermethrin induced atypia in the ovary and uterus, and decreased the ovulation sites and the number of embryos. Cypermethrin-induced oxidative stress during pregnancy, decreased the parturition rate as well as the number and weight of offspring and increased the incidence of morphological malformations in the offspring. Administration of propolis to cypermethrin-treated animals mitigated cypermethrin-induced reproductive toxicity.

Using Pro/E and ANSYS to Build Finite Element Models

Possible alternatives are studied. By comparing the rail-wheel model constructed by these two packages, the benefits of mixed-use of Pro/E and ANSYS for complex assembly modeling are verified.

基于PRO/E的混流式水轮机转轮三维实体建模

混流式水轮机因其叶片为空间扭曲形态,三维实体建模较为困难,利用PRO/E与AutoCAD相结合,以Auto CAD中的叶片平面木模图为基础,利用PRO/E建模软件中的三维功能,采用导入点数据文件形成叶片各横截面,面实体化形成叶片三维体的方法建出叶片实体。通过使用PRO/E中旋转切割功能对进水边、出水边、上冠及下环各部位进行曲面光滑处理,构建出更加满足水力要求的转轮三维空间型面,从而可准确得到由平面图到三维体所表达的转轮实体。

Willingness of Agricultural Workers to Conduct E-commerce of Agricultural Products Based on GEM Model

At present,the development of e-commerce is slow for agricultural products in China. Taking agricultural workers as the research object,this paper analyzed factors influencing the implementation of e-commerce of agricultural products. Besides,from the enterprise status,market conditions,and groundings,with the aid of the GEM( Groundings-Enterprises-Markets) model,it evaluated the factors influencing the development of e-commerce of agricultural products. Then,using SPSS software,it analyzed factors and came up with improvement recommendations. The results show that 59% of the respondents are willing to conduct e-commerce,and the status of the enterprises,market conditions and groundings are main factors influencing the implementation of e-commerce of agricultural products. Therefore,it is required to increase industrial concentration,promote cooperation between small and medium-sized enterprises( SMEs),and strengthen infrastructure construction,so as to promote the development of e-commerce of agricultural products.

融合高斯白噪声的PROSPECT模型的柑橘叶片叶绿素反演

叶绿素是反映植被光合能力的重要指标。为了建立具有普适性的柑橘叶片叶绿素的反演模型,利用PROSPECT模型建立模拟光谱后采用3种特征选取的方法建模,分别为基于敏感性波段(Sensitivity Band,SA)的特征选取,记为PRO-SA模型;采用竞争自适应加权算法(Competitive Adaptive Weighting Algorithm,CARS)的特征选取,记为PRO-CARS模型;采用连续投影算法(Successive Projection Algorithm,SPA)的特征选取,记为PRO-SPA模型。结果表明,①PRO-SPA模型为最优反演模型,其决定系数R^(2)相较原始光谱提升了0.07;②在最优PRO-SPA模型中重采样并对模拟光谱进行多元散射矫正(Multiple Scattering Correction,MSC)后加入高斯白噪声,加入信噪比为80 dB的高斯白噪声的模拟光谱在PRO-SPA模型中表现出最优的反演精度,其决定系数R 2为0.6903,均方根误差(Root Mean Square Error,RMSE)为12.98,相比较原始光谱反演提升了0.15,表明了该方法对于柑橘叶片的光谱模拟以及叶绿素反演的可行性。

Simplified Thermodynamic Model for Pro-Eutectoid Ferrite Formation in Multicomponent Structural Steel

By introducing aparameter of difference in ferrite formation temperature between binary Fe-C and multicomponent system,and referring to the thermodynamic model for Fe-C binary system,a simplified thermodynamic model for pro-eutectoid ferrite formation in Fe-ΣXiC multicomponent structural steels(Xi=Mn,Si,Mo,Cr,Ni or Ti,etc)was suggested.The comparison of the calculated Ae3 temperatures with the measured data of steels 42 shows that the relative standard deviation and root-mean-square(RMS)error between them are only 0.71% and 8.92 K,respectively.However,the deviations between the same measured data and the values calculated from the superelement model are as high as 1.86% and 23.83 K,respectively.It can be concluded that the simplified thermodynamic model for pro-eutectoid ferrite formation in multicomponent structural steels is acceptable and the calculated Ae3 temperatures are in good agreement with the experimental data.

Competitiveness Analysis of Processing Industry Cluster of Livestock Products in Inner Mongolia Based on "Diamond Model"

Using Michael Porter's "diamond model", based on regional development characteristics, we conduct analysis of the competitiveness of processing industry cluster of livestock products in Inner Mongolia from six aspects (the factor conditions, demand conditions, corporate strategy, structure and competition, related and supporting industries, government and opportunities). And we put forward the following rational recommendations for improving the competitiveness of processing industry cluster of livestock products in Inner Mongolia: (i) The government should increase capital input, focus on supporting processing industry of livestock products, and give play to the guidance and aggregation effect of financial funds; (ii) In terms of enterprises, it is necessary to vigorously develop leading enterprises, to give full play to the cluster effect of the leading enterprises.

Thermal Modeling of a Multilayer Integrated LC Filter for Temperature Distribution Calculation

Thermal behavior of integrated passive components has become an important issue when designing these components. This paper presents the thermal modeling of a multilayer integrated LC filter used in DC-DC step-down converter for temperature distribution calculation. The approach used for this analysis is based on thermal equivalent circuit. Temperature distribution is obtained from algebraic equation, which is in vector and matrix form. The results of analytical calculation are compared with simulation results from finite element method. These results showed a good correlation.

Numerical modeling of flow in continuous bends from Daliushu to Shapotou in Yellow River

The upper reach of the Yellow River from Daliushu to Shapotou consists of five bends and has complex topography. A two-dimensional Re-Normalisation Group （RNG） k-ε model was developed to simulate the flow in the reach. In order to take the circulation currents in the bends into account, the momentum equations were improved by adding an additional source term. Comparison of the numerical simulation with field measurements indicates that the improved two-dimensional depth-averaged RNG k-e model can improve the accuracy of the numerical simulation. A rapid adaptive algorithm was constructed, which can automatically adjust Manning＇s roughness coefficient in different parts of the study river reach. As a result, not only can the trial computation time be significantly shortened, but the accuracy of the numerical simulation can also be greatly improved. Comparison of the simulated and measured water surface slopes for four typical cases shows that the longitudinal and transverse slopes of the water surface increase with the average velocity upstream. In addition, comparison was made between the positions of the talweg and the main streamline, which coincide for most of the study river reach. However, deviations between the positions of the talweg and the main streamline were found at the junction of two bends, at the position where the river width suddenly decreases or increases.

Prediction of antigenic determinants of trichosanthin by molecular modeling

The antigenic determinants of trichosanthin were predicted by molecular modeling. First, the threedimensional structure model of the antigen-binding fragment of anti-trichosanthin immunoglobulin E was built on the basis of its amino-acid sequence and the known three-dimensional structure of an antibody with similar sequence. Secondly, the preferable antigen-antibody interactions were obtained based on the known three-dimensional structure of trichosanthin and of the hypervariable regions of anti-trichosanthin immunoglobulin E. Two regions in the molecular surface of trichosanthin were found to form extensive interactions with the hypervariable regions of the antibody and have been predicted to be the possible antigenic determinants: one is composed of two polypeptide segments, Ile201-Glu210 and Ile225-Asp229, which are close to each other in the three-dimensional structure; and the other is the segment Lys173-Thr178. The former region seems to be the more reasonable antigenic determinant than the latter one.

Simulation of the Influence of Ion-Produced NO_X and HO_X Radicals on the Antarctic Ozone Depletion with a One-Dimensional Model

A one -dimensional time-dependent photochemical model is used to simulate the influence of ion-produced NOx and HOx radicals on the Antarctic ozone depletion in polar night and polar spring at a latitude of 73 degrees south.Vertical transport and nitrogen-oxygen (NOx). hydrogen-oxygen (HOx) production by ionic reactions have been introduced into the model.NOx and HOx produced by precipitating ions are transported into the lower stratosphere by vertical motion and have some effects in the development of the Antarctic ozone depletion.From winter through spring the calculated ozone column decreases to 269.4 DU. However, this value is significantly higher than the total ozone observed at several Antarctic ozone stations.

Analysis of a Conceptual Model and Assessment of the e-Procurement System in Bangladesh

The public procurement system in Bangladesh has been running by traditional manual process under the flagship of Public Procurement Act (PPA 2006) and Public Procurement Rules (PPR 2008). Public procurement agencies have been facing challenges in this manual tendering system. To overcome this problem and to bring reality to the “Digital Bangladesh” slogan, the Government of Bangladesh introduced the e-Procurement system under the e-GP (Electronic Government Procurement) guideline 2011. After the inception of e-procurement, there is no e-procurement assessment model to improve the e-GP system. The purpose of this research is to develop a conceptual framework and to design an e-procurement assessment model. With this view, we have considered one of the biggest entity Roads and Highways Department (RHD) of the Government of Bangladesh, for field study. Mixed methods along with FGD (Focus Group Discussion), KII (Key Informant Interview), and survey questionnaires are used to collect data from RHD, and then Statistical Package for Social Science (SPSS) software is used for regression analysis and hypothesis testing to develop the e-Procurement assessment model. The novel contribution of the study lies in the test of the hypothesis that focuses on developing the conceptual model of the e-procurement assessment system in Bangladesh. Findings of the study are essential for all Procurement Entity (PE) and suppliers i.e. contractors of RHD who are engaged in the construction of the infrastructure project development project.

A Probabilistic Model for Fatigue Crack Propagation Analysis

A simple probabilistic model for predicting crack growth behavior under random loading is presented. In the model, the parameters c and m in the Paris-Erdogan Equation are taken as random variables, and their stochastic characteristic values are obtained through fatigue crack propagation tests on an offshore structural steel under constant amplitude loading. Furthermore, by using the Monte Carlo simulation technique, the fatigue crack propagation life to reach a given crack length is predicted. The tests are conducted to verify the applicability of the theoretical prediction of the fatigue crack propagation.