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罩壳内抽芯与内外组合对合模设计 被引量:15
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作者 文根保 文莉 史文 《模具工业》 2017年第9期50-54,共5页
通过对玻璃钢罩壳进行分析,阐述了手动脱模与液压缸抽芯脱模的对合模结构,2种结构分别针对不同的生产批量。液压缸抽芯的模具结构降低了劳动强度,上、下外模块中加装电热器,加快了罩壳固化速度,提高了生产效率,该对合成型模压实了罩壳壁... 通过对玻璃钢罩壳进行分析,阐述了手动脱模与液压缸抽芯脱模的对合模结构,2种结构分别针对不同的生产批量。液压缸抽芯的模具结构降低了劳动强度,上、下外模块中加装电热器,加快了罩壳固化速度,提高了生产效率,该对合成型模压实了罩壳壁厚,消除了罩壳成型时各种缺陷。 展开更多
关键词 罩壳 障碍体 抽芯 对合模 电热器
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吹风机玻璃钢外壳对合成形模设计
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作者 文根保 文莉 史文 《模具工业》 2018年第9期42-46,共5页
通过对玻璃钢吹风机外壳的分析,发现外壳批量和成形质量要求不同,其裱糊成形工艺方法和模具结构方案则不同。对于小批量无缺陷外壳可采用石膏凸模真空袋成形工艺;对于中等批量无缺陷外壳可采用铸铝组合凹模和石膏凸模对合成形;对于大批... 通过对玻璃钢吹风机外壳的分析,发现外壳批量和成形质量要求不同,其裱糊成形工艺方法和模具结构方案则不同。对于小批量无缺陷外壳可采用石膏凸模真空袋成形工艺;对于中等批量无缺陷外壳可采用铸铝组合凹模和石膏凸模对合成形;对于大批量无缺陷外壳可采用钢制组合凸凹模对合成形。经过3个阶段试生产,确定采用钢制组合凸凹模对合成形生产零件。 展开更多
关键词 吹风机外壳 裱糊成形 对合模 玻璃钢布 花键轴
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对合左Q-模范畴的性质
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作者 陈晓婷 赵彬 《陕西师范大学学报(自然科学版)》 CAS CSCD 北大核心 2012年第4期6-10,共5页
研究了对合左Q-模范畴的性质.讨论了此范畴的乘积和等子,并给出它们的具体结构;证明了单点集构成的对合左Q-模是此范畴的终对象,且当Q是无零因子对合Quantale时,对合左Q-模范畴有始对象,证明了此范畴不是连通范畴;给出了对合左Q-模范畴... 研究了对合左Q-模范畴的性质.讨论了此范畴的乘积和等子,并给出它们的具体结构;证明了单点集构成的对合左Q-模是此范畴的终对象,且当Q是无零因子对合Quantale时,对合左Q-模范畴有始对象,证明了此范畴不是连通范畴;给出了对合左Q-模范畴的极限结构,同时得到此范畴是完备范畴且有拉回. 展开更多
关键词 对合左Q- 乘积 极限
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玻璃钢通风管成型模设计
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作者 文根保 文莉 史文 《模具工业》 2018年第12期66-70,共5页
通过对对合成型模结构方案的分析,设计了玻璃钢半自动和全自动的成型模,采用液压缸活塞杆实现抽芯和闭合动作,不仅缓解了大批量生产的压力,还减轻了操作工人的劳动强度,并确保了通风管的成型质量。
关键词 通风管 对合成型 液压缸 自动抽芯 玻璃钢
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Modeling method of hybrid systems using extended Petrinets 被引量:1
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作者 周炳海 王世进 陶丽华 《Journal of Southeast University(English Edition)》 EI CAS 2005年第3期304-309,共6页
In order to model effectively hybrid systems,a new modeling method of extended Petri nets,which is called extended object-orient hybrid Petri net (EOHPN),is proposed.To deal with the complexity of hybrid systems, ob... In order to model effectively hybrid systems,a new modeling method of extended Petri nets,which is called extended object-orient hybrid Petri net (EOHPN),is proposed.To deal with the complexity of hybrid systems, object-oriented abstraction mechanisms such as encapsulation and classifications are merged into EOHPN models.To combine the continuous part and discrete part of hybrid systems and to reduce the complexity of hybrid systems,a hybrid Petri net is introduced and extended with object-oriented modeling technology.Development of object models is suggested on the basis of the defined EOHPN.Finally, an application-oriented case is presented to illustrate that how the proposed EOHPN is used to model hybrid systems.The resulting model validates that the EOHPNs can deal with the modeling complexity of hybrid systems. 展开更多
关键词 Petri nets object-oriented model hybrid system MODELING
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Experiments and modeling of double-peak precipitation hardening and strengthening mechanisms in Al-Zn-Mg alloy 被引量:3
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作者 聂小武 张利军 杜勇 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第7期2138-2144,共7页
The aim of the present work is to develop a model for simulating double-peak precipitation hardening kinetics in Al-Zn-Mg alloy with the simultaneous formation of different types of precipitates at elevated temperatur... The aim of the present work is to develop a model for simulating double-peak precipitation hardening kinetics in Al-Zn-Mg alloy with the simultaneous formation of different types of precipitates at elevated temperatures based on the modified Langer-Schwartz approach. The double aging peaks are present in the long time age-hardening curves of Al-Zn-Mg alloys. The physically-based model, while taking explicitly into account nucleation, growth, coarsening of the new phase precipitations and two strengthening mechanisms associated with particle-dislocation interaction (shearing and bypassing), was used for the analysis of precipitates evolution and precipitation hardening during aging of Al-Zn-Mg alloy. Model predictions were compared with the measurements of Al-Zn-Mg alloy. The systematic and quantitative results show that the predicted hardness profiles of double peaks via adding a shape dependent parameter in the growth equation for growth and coarsening generally agree well with the measured ones. Two strengthening mechanisms associated with particle-dislocation interaction (shearing and bypassing) were considered operating simultaneously in view of the particle size-distribution. The transition from shearing to bypassing strengthening mechanism was found to occur at rather early stage of the particle growth. The bypassing was found to be the prevailing strengthening mechanism in the investigated alloys. 展开更多
关键词 Al-Zn-Mg alloy double-peak precipitation precipitation hardening MODELLING mechanical properties strengthening mechanisms
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Modeling and Simulation of Heterogeneous Catalyzed Propylene Polymerization 被引量:2
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作者 刘兴高 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第4期545-553,共9页
A novel mathematical model for single particle slurry propylene polymerization rising heterogeneous Ziegler-Natta catalysts has been developed to describe the kinetic behavior, the molecular weight-distribution, the m... A novel mathematical model for single particle slurry propylene polymerization rising heterogeneous Ziegler-Natta catalysts has been developed to describe the kinetic behavior, the molecular weight-distribution, the monomer concentration, the degree of polymerization, the polydispersity index (PDI), etc. This model provides a more valid mathematical description by accounting for the monomer diffusion phenomena at two levels as multigrai model counts, and obtains results that are more applicable to the conditions existing in most polymerizations of industrial interest. Considering that some models on the mesoscale phenomena are so complex that some existingmodeling aspects have to be simplified or even neglected to make the model convenient for use in interesting engineering studies, it is very important to put some effort into determining what sort of numerical analysis works bestfor these problems. For this reason, special attentionis.paid to these studies to explorean efficient algorithm usingadaptive grid-point spacing in a tlnlte-ditterence technique to tlgure out more practical mass transport models andconvection-diffusion models efficiently. The reasonable outcomes, as well as the significant computation time saving, have been achieved, thereby displaying the advantage of this calculation method. 展开更多
关键词 modeling and simulation propylene polymerization mass transfer diffusion and convection
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New dispatching rule in furniture production scheduling for reducing weather impacts
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作者 王瑞华 费树岷 刘卿卿 《Journal of Southeast University(English Edition)》 EI CAS 2016年第3期379-384,共6页
In order to reduce the possibility that quality problems occur resulting from “ bad ” weather, a new dispatching rule is designed for the job sequencing problem in the machine shop of a wood furniture factory. First... In order to reduce the possibility that quality problems occur resulting from “ bad ” weather, a new dispatching rule is designed for the job sequencing problem in the machine shop of a wood furniture factory. First, two indices including risky duration and risk magnitude are established to characterize the weather conditions. Based on these two indices, the job suitability under the future air state is derived by the fuzzy decision method, and integrated with atraditional heuristic to compute the dispatching priority of each job. Then, a new measure matching degree is constructed to evaluate the effectiveness of the dispatching rule. The greater the matching degree, the smaller the possibility that the quality problems of wood products occur. Finally, simulation experiments show that the dispatching rule can greatly increase the matching degree while maintaining low weighted tardiness. 展开更多
关键词 dispatching rule fuzzy decision SUITABILITY relative humidity
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Phenomenology of Friedberg-Lee Texture in Left-Right Symmetric Model
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作者 LUO Min-Jie LIU Qiu-Yu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第8期451-458,共8页
We consider that the Higgs triplet Yukawa coupling takes the Friedberg-Lee texture, and the Higgs doublet Yukawa coupling simply identifies with the diagonal Yutawa coupling of charged lepton in the context of left-ri... We consider that the Higgs triplet Yukawa coupling takes the Friedberg-Lee texture, and the Higgs doublet Yukawa coupling simply identifies with the diagonal Yutawa coupling of charged lepton in the context of left-right symmetric model. In this scenario, the phenomenology, including effective neutrino masses, mixings, and thermal flavor-dependent leptogenesis and lepton flavor violation decays are studied. We investigate the combined constrain of the parameters in this scenario and test its consistency with present data. 展开更多
关键词 neutrino mass neutrino mixing flavor-dependent leptogenesis lepton flavor violation Friedberg-Lee texture
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Medical care service model combined with support policy development and theoretical research
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作者 GAN Zhihui SU Manying 《International English Education Research》 2016年第1期14-17,共4页
China has entered the aging society, on the one hand, the number of elderly people in the gradual increase in the number of the corresponding oldest old, disabled elderly, and other semi-disabled elderly is also incre... China has entered the aging society, on the one hand, the number of elderly people in the gradual increase in the number of the corresponding oldest old, disabled elderly, and other semi-disabled elderly is also increasing; on the other hand, family pension function is weakening. This brings new problems and challenges to elderly care services and medical services. How to make the elderly a sense of security, the old medical care, doctors explore new mode of raising combined pension service is very important, domestic scholars have done a lot of this, they mainly focus on the medical support pension model combining content, doctors pension service support combined mode and manner of service objects and the advantages and problems of the medical support combined pension model is discussed. Firstly, from "medical support integration" policy development view, then from the above three aspects of the research scholars to sort out and summarize, try to identify the lack of exploration and research, indicate the direction for further research. 展开更多
关键词 COMMUNITY care services health support binding REVIEW
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Predication of plasma concentration of remifentanil based on Elman neural network 被引量:1
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作者 汤井田 曹扬 +1 位作者 肖嘉莹 郭曲练 《Journal of Central South University》 SCIE EI CAS 2013年第11期3187-3192,共6页
Due to the nature of ultra-short-acting opioid remifentanil of high time-varying,complex compartment model and low-accuracy of plasma concentration prediction,the traditional estimation method of population pharmacoki... Due to the nature of ultra-short-acting opioid remifentanil of high time-varying,complex compartment model and low-accuracy of plasma concentration prediction,the traditional estimation method of population pharmacokinetics parameters,nonlinear mixed effects model(NONMEM),has the abuses of tedious work and plenty of man-made jamming factors.The Elman feedback neural network was built.The relationships between the patients’plasma concentration of remifentanil and time,patient’age,gender,lean body mass,height,body surface area,sampling time,total dose,and injection rate through network training were obtained to predict the plasma concentration of remifentanil,and after that,it was compared with the results of NONMEM algorithm.In conclusion,the average error of Elman network is 6.34%,while that of NONMEM is 18.99%.The absolute average error of Elman network is 27.07%,while that of NONMEM is 38.09%.The experimental results indicate that Elman neural network could predict the plasma concentration of remifentanil rapidly and stably,with high accuracy and low error.For the characteristics of simple principle and fast computing speed,this method is suitable to data analysis of short-acting anesthesia drug population pharmacokinetic and pharmacodynamics. 展开更多
关键词 Elman neural network REMIFENTANIL plasma concentration predication model
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Structural Synthesis, Dynamic Modeling and Analysis of a 3-DOF Asymmetric Parallel Mechanism
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作者 Rynaldo Zanotele Hemerly de Almeida and Tarcisio Antonio Hess-Coelho 《Journal of Mechanics Engineering and Automation》 2011年第6期481-490,共10页
Most research papers about parallel kinematic chainmechanisms investigate symmetric robot manipulators, in which all the limbs connecting the end-effector to the fixed based are composed by the same sequence of links ... Most research papers about parallel kinematic chainmechanisms investigate symmetric robot manipulators, in which all the limbs connecting the end-effector to the fixed based are composed by the same sequence of links and joints. Contrarily, in some manipulation tasks the velocity and stiffness requirements are anisotropic. In such cases, the asymmetric parallel kinematic chain mechanisms may offer advantages. This work objective is to present the synthesis, dynamic modeling and analysis of a 3-dof asymmetric parallel chain mechanism, conceived as a robot manipulator for pick-and-place operations. Firs't, a structural synthesis, resulting in a three translations end-effector, and a kinematic modeling are carried out. Then, the inverse dynamic modeling is developed by employing the virtual work principle. Based on the model equations and on the saturation of the mechanism actuators, a maximum acceleration analysis is performed and shows that although the mechanism has a parallel architecture its actuators influences on the 3-dof are quite decoupled. 展开更多
关键词 PARALLEL ASYMMETRIC SYNTHESIS DYNAMIC modeling.
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Correlation between welding and hardening parameters of friction stir welded joints of 2017 aluminum alloy 被引量:1
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作者 Hassen BOUZAIENE Mohamed-Ali REZGUI +1 位作者 Mahfoudh AYADI Ali ZGHAL 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第5期1064-1072,共9页
An experimental study was undertaken to express the hardening Swift law according to friction stir welding (FSW) aluminum alloy 2017. Tensile tests of welded joints were run in accordance with face centered composit... An experimental study was undertaken to express the hardening Swift law according to friction stir welding (FSW) aluminum alloy 2017. Tensile tests of welded joints were run in accordance with face centered composite design. Two types of identified models based on least square method and response surface method were used to assess the contribution of FSW independent factors on the hardening parameters. These models were introduced into finite-element code "Abaqus" to simulate tensile tests of welded joints. The relative average deviation criterion, between the experimental data and the numerical simulations of tension-elongation of tensile tests, shows good agreement between the experimental results and the predicted hardening models. These results can be used to perform multi-criteria optimization for carrying out specific welds or conducting numerical simulation of plastic deformation of forming process of FSW parts such as hydroforming, bending and forging. 展开更多
关键词 friction stir welding response surface methodology face centered central composite design HARDENING simulation relative average deviation criterion
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Comprehensive Evaluation Model of Reservoir Operation Based on Improved Set Pair Analysis 被引量:4
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作者 任炳昱 孙宜超 +2 位作者 周正印 程正飞 胡兴富 《Transactions of Tianjin University》 EI CAS 2013年第1期25-28,共4页
A comprehensive evaluation model based on improved set pair analysis is established. Considering the complexity in decision-making process, the model combines the certainties and uncertainties in the schemes, i.e., id... A comprehensive evaluation model based on improved set pair analysis is established. Considering the complexity in decision-making process, the model combines the certainties and uncertainties in the schemes, i.e., identical degree, different degree and opposite degree. The relations among different schemes are studied, and the traditional way of solving uncertainty problem is improved. By using the gray correlation to determine the difference degree, the problem of less evaluation indexes and inapparent linear relationship is solved. The difference between the evaluation parameters is smaller in both the fuzzy comprehensive evaluation model and fuzzy matter-element method, and the dipartite degree of the evaluation result is unobvious. However, the difference between each integrated connection degree is distinct in the improved set pair analysis. Results show that the proposed method is feasible and it obtains better effects than the fuzzy comprehensive evaluation method and fuzzy matter-element method. 展开更多
关键词 set pair analysis comprehensive evaluation model gray correlation reservoir operation
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Imperfect preventive maintenance for numerical control machine tools with log-linear virtual age process 被引量:4
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作者 郭俊锋 芮执元 +1 位作者 冯瑞成 魏兴春 《Journal of Central South University》 SCIE EI CAS 2014年第12期4497-4502,共6页
Based on the log-linear virtual age process, an imperfect preventive maintenance policy for numerical control(NC)machine tools with random maintenance quality is proposed. The proposed model is a combination of the Ki... Based on the log-linear virtual age process, an imperfect preventive maintenance policy for numerical control(NC)machine tools with random maintenance quality is proposed. The proposed model is a combination of the Kijima type virtual age model and the failure intensity adjustment model. Maintenance intervals of the proposed hybrid model are derived when the failure intensity increase factor and the restoration factor are both random variables with uniform distribution. The optimal maintenance policy in infinite time horizon is presented. A numerical example is given when the failures of NC machine tools are described by the log-linear process. Finally, a discussion is presented to show how the optimal results depend on the different cost parameters. 展开更多
关键词 reliability imperfect preventive maintenance virtual age log-linear process failure intensity
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Studying on equilibriums between price and QoS in multi-provider overlay access networks
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作者 王玉峰 Wang Wendong 《High Technology Letters》 EI CAS 2006年第2期129-135,共7页
From the viewpoint of game theory, this paper proposes a model that combines QoS index with price factor in overlay access networks, and uses the multinomial logit (MNL) to model the choice behaviour of users. Each ... From the viewpoint of game theory, this paper proposes a model that combines QoS index with price factor in overlay access networks, and uses the multinomial logit (MNL) to model the choice behaviour of users. Each service class is considered an independent and competitive entity offered by each provider, which aims at maximizing its own utility. Based on noncooperative game, we prove the existence and uniqueness of equilibriums between QoS levels and prices among various service classes, and demonstrate the properties of equilibriums. Finally, these results are verified via ntunerieal analysis. 展开更多
关键词 Overlay access network noncooperative game multinomial logit model Nash equilibrium
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Lattice Boltzmann Study of Mixed Convection in a Cubic Cavity
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作者 杜洪艳 柴振华 施保昌 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第7期144-150,共7页
The problem of the mixed convection in a cubic cavity is studied with lattice Boltzmann method. A multiple-relaxation-time lattice Boltzmann model for incompressible flow in the cubic cavity and another thermal lattic... The problem of the mixed convection in a cubic cavity is studied with lattice Boltzmann method. A multiple-relaxation-time lattice Boltzmann model for incompressible flow in the cubic cavity and another thermal lattice Boltzmann model for solving energy/temperature equation are proposed. The present models are first validated through a comparison with some available results, and then, we present a detailed parameter study on the mixed convection in the cubic cavity. The numerical results show that the flow and the Reynolds and Richardson numbers. temperature patterns change greatly with variations of 展开更多
关键词 lattice Boltzmann method multiple-relaxation-time model mixed convection
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Experimental and Theoretical Study on p-Chlorofluorobenzene in the S0,S1 and D0 States
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作者 Jia-nan Fan Ting-ting Cui +2 位作者 Zheng-bo Qin Xian-feng Zheng Zhi-feng Cui 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2020年第4期401-410,I0001,共11页
The geometric structures and vibration frequencies of para-chlorofluorobenzene(p-Cl FPh)in the first excited state of neutral and ground state of cation were investigated by resonanceenhanced multiphoton ionization an... The geometric structures and vibration frequencies of para-chlorofluorobenzene(p-Cl FPh)in the first excited state of neutral and ground state of cation were investigated by resonanceenhanced multiphoton ionization and slow electron velocity-map imaging.The infrared spectrum of S0 state and absorption spectrum for S1←S0 transition in p-Cl FPh were also recorded.Based on the one-color resonant two-photon ionization spectrum and two-color resonant two-photon ionization spectrum,we obtained the adiabatic excited-state energy of p-Cl FPh as 36302±4 cm^-1.In the two-color resonant two-photon ionization slow electron velocity-map imagin spectra,the accurate adiabatic ionization potential of p-Cl FPh was extrapolated as 72937±8 cm^-1 via threshold ionization measurement.In addition,FranckCondon simulation was performed to help us confidently ascertain the main vibrational modes in the S1 and D0 states.Furthermore,the mixing of vibrational modes between S0→S1 and S1→D0 has been analyzed. 展开更多
关键词 Resonance-enhanced multiphoton ionization Slow electron velocity-map imaging Duschinsky mixing para-Chlorofluorobenzene
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An aligned mixture probabilistic principal component analysis for fault detection of multimode chemical processes 被引量:5
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作者 杨雅伟 马玉鑫 +1 位作者 宋冰 侍洪波 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第8期1357-1363,共7页
A novel approach named aligned mixture probabilistic principal component analysis(AMPPCA) is proposed in this study for fault detection of multimode chemical processes. In order to exploit within-mode correlations,the... A novel approach named aligned mixture probabilistic principal component analysis(AMPPCA) is proposed in this study for fault detection of multimode chemical processes. In order to exploit within-mode correlations,the AMPPCA algorithm first estimates a statistical description for each operating mode by applying mixture probabilistic principal component analysis(MPPCA). As a comparison, the combined MPPCA is employed where monitoring results are softly integrated according to posterior probabilities of the test sample in each local model. For exploiting the cross-mode correlations, which may be useful but are inadvertently neglected due to separately held monitoring approaches, a global monitoring model is constructed by aligning all local models together. In this way, both within-mode and cross-mode correlations are preserved in this integrated space. Finally, the utility and feasibility of AMPPCA are demonstrated through a non-isothermal continuous stirred tank reactor and the TE benchmark process. 展开更多
关键词 Multimode process monitoring Mixture probabilistic principal component analysis Model alignment Fault detection
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Research on the road landscape evaluation system with the emphasis on the landscape ecology
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作者 Qian Xiaowei Yao Weimian 《International English Education Research》 2014年第5期82-88,共7页
As the idea of the sustainable development wins support among the people, people have already realized that not only should the road have the transportation function, but we also should consider the rationality of the... As the idea of the sustainable development wins support among the people, people have already realized that not only should the road have the transportation function, but we also should consider the rationality of the road construction fi'om the multiple angles of the landscape ecology, and the visual art and so on. From the point of view of the landscape ecology, combined with the characteristics of the landscape ecology and the overall targets and requirements of the evaluation, this article constructs a three-tier system of indicators, uses the fuzzy comprehensive evaluation model based on the analytic hierarchy process to evaluate the road landscape, and makes an empirical analysis with the evaluation of the road landscape fi'om the Luoshi Road to the East Lake Road in the Second Loop of Wuhan City as an example. 展开更多
关键词 Landscape ecology road landscape evaluation method indicator system
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