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Sept4th

SS304 steel

 SS304 steel ,SS304 steel prices,SS304 china

Japanese and Chinese do not belong to one language family, but there are a lot of words in the same forms between them, of which there are a considerable numbers of homographs. The study in Japanese and Chinese homographs is of great significance in Japanese and Chinese language teaching. In addition, it also involves problems of language contact between Japanese and Chinese, and it’s also of great significance in the research of lexical history, especially in the historical evolution of meaning. The goal of this paper is to find the motivation and patterns in the process of meaning evolution by a comparative study of Japanese and Chinese homographs.In the first chapter, I reviewed the background of Japanese and Chinese homographs and described what is Japanese and Chinese homographs, the signifinance of this study and the present research status, and gave an account of the research materials and methods.On this basis, in the second chapter I described the distribution of Japanese and Chinese homographs and its position in Japanese and Chinese as well as the previous researc SS304 steel ,SS304 steel prices,SS304 chinah, and then I presented my point of view to study Japanese and Chinese homographs with a combanation of synchronic and diachronic perspectives. In addition, I also did some case studies of representative two-syllable words and monosyllabic words, and put forward my own views by further in-depth analysis. First of all, I believe that the current studies of Japanese and Chinese homographs can only describe the process of meaning evolution, but can not derive a theory to explain the meaning evolution by summarized results obtained from the analysis. Secondly, exploring the patterns of meaning evolution needs at least two premises, that is, to make it clear that what is the meaning first and second to establish the methods to describe meaning and meaning evolution.Next, in the third chapter, I discusses the relationship between language contact and the study of Chinese and Japanese homographs. To determine the etymological relationship between languages such as Japanese and Chinese, which are difficult to establish the rules of the phonetic correspondence, it is limited to apply the previous method of comparative linguistics in Europe. We should find out the mechanism of language contact, but we can only assume that there are stages of language contact now.In summary, by the research and analysis of the language contact between Japanese and Chinese through case studies of Japanese and Chinese homographs, I obtained the conclusion that the Japanese and Chinese share a common concept,which is quite common. I think we can assume that some kind of "core meaning" exists. And in order to accurately describe the process of the meaning evolution of Japanese and Chinese homographs, we need a common coordinate between Japanese and Chinese, which means to establish a precise and universal method to describe the meaning. A key point in describing the meaning evolution is the dynamic perspective in the lexical conceptual structure and generative lexicon. This view believes that there should be a "core meaning " first, while the other meaning and usage are generated from the core meaning. This is one of the indispensable elements to establish a method to describe the meaning evolution.This paper, which is based on single case studies, explained the study of Japanese and Chinese homographs theoretically, and fixed its position in linguistics since its establishment to present, and made clear the significance of the study of Japanese and Chinese homographs.  SS304 steel ,SS304 steel prices,SS304 china

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Sept4th

SS304L steel ,SS304L steel prices,SS304L china

SS304L steel ,SS304L steel prices,SS304L china

【Abstract】 This thesis is an examination of the cultural activities and journey of self-identification of the Taiwanese Zhang Shen Qie, Zhang Wo Jun, Hong Yan Qiu, and Zhong Li He in Peking during the fall. Four people grew up in Taiwan during Japanese occupation, and later moved to Peking. Through case study, the thesis discusses the awkward politics and environment they encountered during their time in Peking. The first chapter analyzes the Zhang Shen Qie’s role in the collaboration between Literature to serve Japan organization and the Intellectual in Peking to create Arts Magazine. In addition, the chapter also highlights the delicate positions of Taiwanese intellectuals through the struggle between the new and old writer in northern China’s commuSS304L steel ,SS304L steel prices,SS304L chinanity. The 2nd and 3rd chapters discuss Zhang Wo Jun and Hong Yan Qiu’s comply in public but oppose in private and passive resistance in the translation and education field. These chapters also discuss the different types of Intellectuals in the special historical context. The 4th chapter discusses Zhong Li He’s point of view from and his cultural activities in nativist literature. It also examines his journey as the ambiguous Taiwanese caught between motherland and Japan’s East Asian nation to finding his cultural identify.After reflecting on the generalization and essence of the identification model, this thesis strategically uses multiple and fluid perspectives to discuss Taiwan Intellectual’s special political and cultural voice in Peking during the fall. Besides using their publications, the thesis also includes their personal diaries, letters, and anecdotes as examples to describe the tension between the reality and written expression. Furthermore, these items are used to personalize the understanding of "cultural identification" and to present the shift and struggle of power in the cultural communitySS304L steel ,SS304L steel prices,SS304L china

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Sept4th

SS304H steel, SS304H steel prices, SS304H china

SS304H steel SS304H steel prices SS304H china In this thesis, I categorize four types of errors of the "ba" Construction in Altaic Chinese and figure out the internal error-generating mechanism, based on a large amounts of errors of the "ba"(把) Construction of Korean and Uygur stude nts and the Mongolian-Manchu Chinese. This study can help us further understan d the "ba" construction in mandarin and provide a new insight of the instructio n of "ba" construction in Chinese as a second language.The main arguments of the thesis are:1. It claims that the typical "ba" construction in Chinese is "S Neg/Aux BA O V Disposal R了" and its core meaning of the construction is "Disposal Causati ve".2. It categorizes the main error types of the "ba" Construction of Korean students, based on the large collections of the "ba" Construction errors of them.3. By analyzing the typical errors of the "ba" ConstSS304H steel SS304H steel prices SS304H chinaruction of Korean stude nts, it categorizes three types of error-generating mechanism:1) Object marker,2) the Causative structures,3) Object-embedded Sentence.4. It observes that in terms of "ba" construction, there are similarities amon g the error phenomena of Korean students and the features of dialects in New te rritory、Blue sea provinces and also in some other northern dialects described in historical documents. According to this observation, this thesis interprets the gen erating mechanism of "ba" Construction in the history. It claims that the leading role of "ba" in North Chinese has something to do with its contacts with the Altaic languages. Specifically, the resigning of "jiang(将)" and abruptly flourishin g of "ba"(把) in North Chinese, is due to the sound similarity between "ba" a nd the objective marker in the Jurchen and Manchu language, which is [ba] and [be]. It further holds that "surviving together" and "mutually rejecting" principle s are universally essential to borrowing mechanism in language contacts——"the essential features of Magnet", it is really worth referring to the theory of langua ge contact in linguistic universal.5. This thesis also claims that it is possible to use the four types of errors a ndSS304H steel SS304H steel prices SS304H china the analysis of the special "ba" Constructions in this thesis to predict the ot her contemporary Chinese dialects which have closely contacted with the Altaic 1 anguages and the historical Altaic Chinese documents.6. This thesis, by the typological comparisons of the pre-posing and post-pos ing of Negative and Auxiliary verbs, for the first time, points out the particularit y of the word order of "Neg/Aux+PP+VP" in Chinese and its remaining verbal f eatures of "ba" in the construction.7. By systematical analysis of the causative structures in Altaic, this thesis cl aims that the confusing usage of "Pivotal(使)" and "Disposal(把)" of Altaic Stu dents is because of the dual interference of object marker and the causative struc tures in Altaic.In the final chapter, some issues which need further studies are provided

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Sept4th

SS316 steel, SS316 steel prices, SS316 china

With the quick development of society economy and continuous acceleration of urbanization process, urban vehicle population continues to increase and urban traffic demands increase sharply. Many problems about traffic that includes traffic congestion, traffic accidents, environmental pollution and energy shortage have become a universal problem. Encourage public transport and pay attention to pedestrian traffic, has been the important management strategy to achieve green traffic in many countries and regions. As the complex urban transportation network node, passenger hub is the area of vary transport mode transforming and vary direction passenger flow assembling based on joining the vary transport mode and exerting its function fully. The service level and transfer efficiency of passenger hub affects the attractive power to the passengers directly, and at the same time it is the key joint to improve the convenience, amenity and safety of urban transportation system.Constructing micro behavior models and related algorithms based on computer function and data simulation technology is one of the efficient approaches to understanding the complex evolution phenomenon of pedestrian traffic flow in passenger transfer hub. Most of current pedestrian flow simulation models and software are designed for the safety evacuation simulation and parameters of the models were always foreign standards. Its needed improved in the micro pedestrian traffic behavior theory and navigation model and algorithm of pedestrian agent for simulating the complex evolution process of pedestrian traffic flow in the complex passenger transfer hub in which the activities are varies.Firstly, pedestrian traffic flow models and related simulation technology developing status were introduced in this paper, the pedestrian traffic characteristics were analyzed in the passenger transfer hub based on the field experimental data, including the pedestrian traffic behavior, fundamental diagram of pedestrian traffic flow of vary pedestrian facilities, chaos characteristics of short-term pedestrian traffic flows. The outputs showed that the pedestrian free speed in transfer hub is higher than other environments and most pedestrian facility traffic flow have chaos characteristics, except escalators.Pedestrian behavior theory and models were analyzed based on traffic engineering and cognitive psychology theories. Pedestrian activity for receiving service of facility was analyzed, which was absent in current pedestrian behavior theory, and service activity model was constructed. A micro pedestrian behavior theory framed was proposed completely, pedestrian dynamic model and choice model of stairs and escalators were calibrated based on field data. Based on Schemata terminology and the object affordance theory in cognitive psychology field, the constructing and function of passenger transfer hub were analyzed, passenger transfer hub facilities were classified and abstract by the function and construction analyzing. The facility topology network model was constructed based on the link and trait point definition.A complete agent navigation model was constructed based on Montello navigation theory, micro pedestrian traffic behavior and finite state machine model, and algorithms of behavior model in different level were proposed. Considering the limited vision of pedestrian agent,the velocity of current path as the main factor to route choice behavior, a quasi-static route choice model was proposed in this paper. Cooperation strategy of agents in the normal pedestrian traffic flow was concerned, a dynamic target updating algorithm for agent in the passageway was proposed for resolving the deadlock of pedestrian agent at the curve conduit. By the proposed crowd holonic search method in this paper, dynamic crowd obstacles avoidance algorithm for pedestrian agent who in the little value pedestrian flow direction in the traffic interweave areas was proposed for resolve the deadlocks appearance in the interweave areas.Finally, considering the contiguous space and discrete time data of simulation system output, statistic method of pedestrian traffic flow parameters and density dynamic showing algorithm were proposed. The pedestrian social force model was validated based on field data and output data of PSSITH simulation system by using the Kolmogorove-Smirnove test method. The social force model which calibrated in this paper was compared with the related research data by analyzing the mean standard error of simulation and real data based on netlogo multi-agent simulation platform. The transfer time mean value of pedestrian in passenger transfer hub was analyzed by using student’s test method based on the real data which were collected from field. The chaotic characteristic of simulation short term pedestrian traffic volume was analyzing by using Lyapunov exponent index. Two real case were analyzed based on the PSSITH, bottlenecks analyze and pedestrian traffic demand loading methods were proposed in the case.This paper will enrich the pedestrian traffic behavior theory and improve the methodology, the navigation model and algorithm proposed in this paper can offer the key algorithm and theoretical foundation, so that researchers can analyze complex evolution process of pedestrian traffic flow more specifically

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Sept4th

SS316 steel,SS316 steel prices, SS316 china

 SS316 steel SS316 steel prices SS316 chinaAs a transition state from molecular to macroscopic materials, the structures and properties of cluster have changed with the different size. This change can reflect the process from miso to misco material. The study on the form, structures, and properties of cluster can bridge between atom and material, make the cluster science develop rapidly. With the development of nanomaterial, the mental Pb cluster has been attracted much attention and investigated in both theoretical and experimental studies. On the experimental, much more research focus on forming the cluster and measuring the structures and properties of lead cluster. Mainly experimental techniques, such as the direct laser vaporization (DLV), laser vaporization pours into the ion drift tube technology, the inject ion drift tube techniques, photofragmentation and photodissociation, photoionization and photodetachment photoelectron energy specturn (PES) et al. are used to study the structures and properties of Pb clusters. In the fundamental theoretical research aspect, the research focal point is a group bunch of stable lead structure and the electronic properties. Recently, the main methods are ab initio, the Density Functional Theory, the molecular mechanics and the member dynamic method, Monte Carlo (MC) and so on. In recent years, along with the experiment method and the theoretical calculation level’s enhancement, the research of lead clusters also obtained the rapid development. In this work, we used the genetic algorithm (GA) coupled wi SS316 steel SS316 steel prices SS316 chinath a TB potential of Pb to search for low-energy candidates of Pb clusters, then the structures were further optimized by PAW-PBE function in VASP software. We searched the best stable structures of Pb clusters, and analysesed the properties in details.In this article, we have determined the stable structures of medium-size lead cluster of Pbn (n≦ 30). On the base of structures, we have made a series of nature analysis, including the binding energy, second differences in energy, HOMO-LUMO gaps (the highest occupied molecular orbital and lowest unoccupied molecular orbital), the fragmentation energy, fragmentaion behavior, ionization potential and so on. Through the detailed system’s theoretical calculation, we had determined the stable structure and the electronic properties lead clusters change with the cluster size increses.The main results now are list as follows:(1) The clusters we researched in this work favor closing-compact structures. From our result, we found small Pbn (n≤7) motif is similar to the structures of Si, and Ge cluster. Pb10 is a capped trigonal prism, and Pb13 favors an encapsulated icosahedron structure. In the range of n = 14 -20, closing-compact structures are dominant in lead clusters, although there exist the layer motifs. For Pb21-30, the clusters also favor the closing-compact structure. In particular, Pb24 is a perfect structure which is the base to form large lead clusters.(2) We analyzed the properties of lead clusters, such as binding energy, second difference in energy, and HOMO-LUMO gaps. It is clear that the binding energy per atom increases rapidly with the cluster size up to n = 8, oscillates in the size range of 9– 19, and then becomes smoother in the range of n = 20– 30. Small humps in the BE curve indicate higher stability for some specific clusters. In particular, there are peaks for the Pbn clusters with n = 4, 7, 10, 13, 15, 17, 24, 28, showing that these clusters have large binding energies and special stabilities.Δ2E as a function shows an oscillating behavior, and Pb4, Pb7, Pb13, Pb15, Pb17, Pb24, Pb28 correspond to local maxima on the curve of the second difference in energy, the results suggest that these clusters are more stable than their neighbors. The HOMO-LUMO gaps of SS316 steel SS316 steel prices SS316 china clusters are large for n = 4, 10, 13, 16, 20, 26, 28. From these analyses, Pb4, Pb10, Pb13, and Pb28 have both large energetic stability as well as reactive stability.(3) The fragmentation of lead cluster was calculated in details. The neutral clusters have the fragmentation of an atom Pb and Pbn-1 in the range of n≤12, and in large size, the cluster favor to dissociate two stable clusters. Compared with the neutral clusters, the charged lead cluster dissociated into Pb and Pbn-1+ in the size of n≤14, and the large clusters also fragmented two stable clusters, thereinto, the larger is the cation cluster n.(4) We have calculated the adiabatic ionization potential of Pbn clusters and found Pb6, Pb10, Pb20, and Pb28 have the large IP than their neighbors. As shown as IP curve, the threshold IP for n = 2 - 4 are larger about by 0.5eV and more than those of other clusters studied in this work. For n = 2 - 13, the IP reduce visibly, and there is a sharp plot at Pb13 cluster. In the large clusters, the IP curve becomes smoothly, and is lower than the IP of small cluster SS316 steel SS316 steel prices SS316 china

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Sept4th

SS316TI steel

SS316TI steel

Steer-by-Wire system is an electronic control steering system with totally new concept which cancels the mechanical joint between the steering wheel and the front wheel; it makes vehicle steering following the driver’s command and generate a reaction torque to the steering wheel, as a virtual feedback of the road feeling by the steering motor and the steering feel motor respectively. Steering-by-Wire system makes the design of steering characteristics more freely and leaves a bigger space for improving the stability and the safety of the vehicle, which represents the future trend of the steering system of the future vehicle, especially intelligent vehicle. The fault tolerance control technology as an important part of control strategy of Steering-by-Wire system is one of major means for guaranteeing reliable operation of the whole system, so it is the indispensable primary factor of the control method for Steering-by-Wire system.This Ph.D. dissertation is based on the project named“Research on Key Technology for Front Wheel Steer-By-Wire Vehicle”(No. 50475009) and“ResSS316TI earch on Control methods and Key Technology for X-By-Wire Vehicle”(No. 50775096) by National Natural Science Foundation of China. Based on the summary of the domestic and foreign research achievements on fault-tolerance control technology for Steer-by-Wire automobile,this dissertation aimed at security and reliability of Steering-by-Wire system and made a deep study of fault tolerant control over main sensors, steering motor and controller. The control method is tested with Hardware-in-Loop simulation. On the basis of this, it is further confirmed by real vehicle test and the Steering-by-Wire automotive is modified from one domestic car. The main research work is summarized as follows:(1)Establish the fault tolerant control method for Steer-by-Wire system based on residualAim at the characteristics of Steer-by-Wire system and the necessity of on-line fault tolerant control, the fault tolerant control method over sensors, steering motor and controller, of Steer-by-Wire system, is studied in this paper. And one residual detecting fault tolerant control algorithm based on Three Voting Protocols is proposed from two sides, including fault diagnosis and fault compensation. It could get the residual matrix for sensor fault tolerance control by the combination of sensor measurement and estimated value, and the fault eigenvector by comparison among different residual, thus realize fault diagnosis. Toward the faulty sensor, fault compensation can be achieved by backup sensor and dual redundant of software eSS316TI stimated value, to make sensors reliable and stable; In fault tolerant control over motor, main parameters of the motor can be obtained by Parameter Identification. The parameter of the motor is estimated too with its working status, by parameter estimation method. And then, the fault tolerant control over motor can be achieved with the residual between estimated value and real parameter of the motor. The fault compensation of motor is mainly warning to driver; In controller fault tolerance, Tri-core structure is adopted and the fault diagnosis residual is built by dual redundant of haSS316TI steelrdware and arbitration of data inside the chip. The fault compensation of controller is accomplished by backup hardware. In a word, according to the characteristics of different components in Steer-by-Wire system and the residual detecting method, the fault tolerance control of sensor, motor and controller is realized.(2)Establish the method for sensor fault tolerant control based on Riccati equation and state estimation with Adaptive Kalman FilterConsidering the construction characteristic of Steer-by-Wire system, the entire system is divided into two parts: steering wheel module and steering actuator module.To the angle sensorSS316TI  in the steering wheel module, software signal estimation can be obtained by the method of faulty signal reconstruction which is based on Riccati equation. Residual matrix will be constructed with the dual-backup sensor. And then, according to Three Voting Protocols, the fault diagnosis can be realized with the given threshold and by using the backup sensor to bring about fault compensation. The sensor fault tolerance of steering actuator module is relatively more complex. Key sensors needing fault tolerance control include pinion shaft steering sensor, rack displacement sensor, yaw rate sensor, lateral acceleration sensor and motor current sensor. On the basis of whole vehicle model combined Steer-by-Wire system, the state estimation methods for Steer-by-Wire automobile is obtained with Adaptive Kalman Filter. And then, based on the above efforts, build residual matrix combining hardware signal and estimated value, and determine residual threshold according to dependencies between different signals and the tire mechanics character. The fault eigenvector will get then, so it realizes sensor fault diagnosis and fault compensation by backup hardware and software estimated value.(3)Establish the method for SS316TImotor fault tole steelant control steelbased on Adaptive Kalman FilterThe steering motor as a source of steering power, it plays an important role in Steer-by-Wire system. In this paper, based on motor model which have built and Adaptive Kalman Filter theory, the parameter estimator for the steering motor is built to estimate internal resistance and torque constant of the motor and the actual value of these two parameters are identified by using the Least Square Algorithm. And the residual can be calculated by the parameter value obtained with the two methods mentioned above. And then, motor fault diagnosis can be achieved with the threshold. After the fault information is acquiredSS316TI , it needs to make travel security by warning to driver.(4)Establish the method for controller fault tolerant control based on Tri-core controller and TTCAN busIn this paper, controller fault tolerant control for steel the Steer-by-Wire system can be implemented by Tri-core controller, and the fault tolerant control of signal conditioning circuit and driver circuit can be done by dual-backup hardware. Three cores consist of two main control chips and one arbitral chip. The arbitral chip shall be mainly responsible for making control decision for fault diagnosis and fault compensation of the signal conditioning circuit, main control chips and driver circuit. The residual can be calculated by hardware signals and the built-in reference values in the arbitral chip, and fault can be determ steelined according to the threshold. And then, fault compensation is realized by backup hardware. Due to the real-time requirement of controller fault tolerant control, the communication between main control chips and arbitral chip needs to meet the real-time requirement. In this paper, the communication among these chips is achieved through TTCAN bus based on event trigger mechanism, to achieve real-time transmission of fault tolerant information. Based on the rSS316TI esearch above, the fault tolerant controller for the Steer-by-Wire system can be made.(5)Design and build Hardware-in-Loop test rig and experimental car of Steer-by-Wire system and verify the fault tolerance method by the experiment in the test rig and experimental carBased on the study above, the rapid prototyping platform is built for the study on fault tolerance control with Matlab/xPC Target. And the Hardware-in-Loop test rig of Steer-by-Wire system is built too, combined hardware of Steer-by-Wire system, resistance simulator and small driving simulator. Under the research result stated above,the fault tolerance control method for sensors, motor and controller of Steer-by-Wire system is validated through Hardware-in-Loop simulation. Taking one domestic brand, class-A vehicle as the platform, the vehicle is modified into a Steer-by-Wire vehicle with our own Steer-by-Wire system. And the fault tolerance control method for sensors, motor and controller is further validated. The result has fully validated the efficiency and accuracy of the fault tolerance algorithm.So all in all, the innovative achievements made in this paper are shown as follow:(1)According to the characteristics of Steer-by-Wire system and the practical situation of fault tolerance control, the fault tolerant control method based on residual detecting is proposed. In accordance with different characteristics of different components including sensor, motor and controller, the residual matrixes for each component can be obtained by the combination of hardware signal and software estimated value. And combining it with the given threshold, make the fault tolerant control of components come true. (2)By applying Adaptive Kalman Filter theory to the fault tolerant control of sensor and motor of Steer-by-Wire system, and with the Steer-by-Wire vehicle model and motor model, the state estimator and the parametSS316TI er estimator are constructed, to provide reference signal for sensor and motor fault tolerant control and fault compensation signal for sensor. According to the actual situation of multi-sensors fault tolerant control, the concept of sensor fault eigenvector is given. Finally, the quick and accurate sensor fault tolerance is realized through a simple comparison of residual.(3)By applying TTCAN bus which is based on event trigger mechanism to the fault tolerance controller design of Steer-by-Wire system, and based on actual needs, the fault tolerant controller is designed by the Tri-core controller architecture which includes two main control chips and one arbitral chip

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Sept4th

SS316H steel

SS316H steel

Electric power steering system is a new type power steering system developed rapidly in recent years. This new system can solve the contradiction between handiness and sensitivity, and has many advantages such as energy saving, environmental protection and easy assemblity. Recently, electric power steering system is gradually replacing the hydraulic and electro-hydraulic power steering system, and becoming automotive technology research focus all over the world.The paper comes from the national 863 project, studying on the electric power steering system stability and current control algorithm to an A0 class car as an object, In this papSS316H er, EPS system steelmodeling, stability, optimal PID parameters, current control strategies and hardware and software development are discussed in detail. Paper is divided into seven chapters.Chapter I is an introduction. A brief introduction of electric power steering system principle, structure and classification was gived. The context of the history and development situation of electric power steering system stability and the current control algorithm were summed up. The main contents of this paper were pointed out.Chapter II is EPS system model establishment. This chapter established the EPS system model with MATLAB/Simulink. In the modeling process, PID feedback control was used. By analyzing the formation of ground-reaction force, the ground reaction force was modled as proportional to the rack displacement. The changes to the moSS316H steeltor electrical parameters, low pass filtering nature of current sensor and characteristics of EPS controller lag were taking into full account in modling process. Though the current sweep experiment, the current step experiment, and the steering wheel turning experiment of frequency domain and time domain methods, the model established was validated.Chapter III is the analysis of EPS stability. The basic concepts of system stability and common determination methods were reviewed. To analyze the EPS system stability, the method of using PID parameters stability regions was proposed. The influence of system stability was studied by drawing three-dimensional PID parameters stability space. And then, the influence of the PID parameters stability region when system parameters are changing was studied, and then the influence on the system stability was got.Chapter IV is the study on the optimal PID parameters with genetic algorithm. The stability, rapidity and accuracy of EPS system were analyzed. By taking into account of all the various performance requirements EPS, the method of using genetic algorithm to optimize PID parameters was proposed. On this basis, the influence of system parameters on the optimal performance and the optimal PID parameters along with the robustness of the system were studied, and the influence of parameters on the system performance were obtained.Chapter V is the study of the current control strSS316H steelategy and its robustness. By analyzing the influence of system parameters on system performance, a current control strategy is proposed which content selecting the curvilinear assistance, motor speed feedforward control, battery voltage compensation and the optimal PID parameters adaptive method. By using Monte-Carlo random sampling test method, the EPS system stability, current control effect and robustness were evaluated.Chapter VI describes the EPS software and hardware system development and the real vehicle validation. The development process of the motor testrig and EPS controller hardware were introduced by describing its composition and realization of each module. The EPS controller software was carried out using uC/OS-II embedded operating system. The motor back-EMF coefficient and the resistance which change with the electric current were measured, and then, a more accurate estimate of motor speed was achieved by varying motor parameters. And at last, the EPS system stability and the current control strategy were validated in a real vehicle.Chapter VII gives a summary of the paper and a research prospect in the future.Through simulation analysis and real vehicle validation for the electric power steering system stability and current control strategy, the main conclusions are as follows:(1) EPS system stability is more sensitive for these parameters than the others: motor resistance, back-EMF coefficient, assist gain and battery voltage.(2) The optimal performance and the optimal PID parameters are sensitive to motor resistance, back-EMF coefficient, assist gain a greater impact and the battery voltage, and insensitive to motor torque coefficient, motor inductance and the elasticity coefficient of the ground reaction force.(3) Current control performance and robustness of EPS can be improved by using curvilinear assistance, motor speed feedforward control, battery voltage compensation and the optimal PID parameters adaptive method.(4) Motor resistance and back-EMF coefficient change with the motor current, and a more accurate motor speed can be estimated using variable parameters.This paper has been innovative in the following areas:(1) The method of using PID parameters stability regions to analyze the EPS system stability was proposed. The influence on the system stability was got by studing the influence of the PID parameters stability region when system parameters are changing. The SS316H steel ethod of getting optimal PID parameters using genetic algorithm was proposed, and the optimal current control method and system robustness can be studied by analyzing the optimal performance and the optimal PID parameters.(2) The current control strategy which contents curvilinear assistance, motor speed feedforward control, battery voltage compensation and the optimal PID parameters adaptive method was proposed. Monte-Carlo random samplin SS316H g test method was proposed to verify the control strategy.(3) A more accurate motor speed estimate method using variable parameters was proposed, in which motor resistance and back-EMF coefficient change with the motor current SS316H steel 

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Sept4th

SS316L steel

SS316L-steel

The pure electric car is one of the engergy saving technology which is recognized by the whole world. At present time, government of each country and automotive industry have agreed on developing pure electric car, and itsSS316Levelopment has -steel become hot spot of automotive industry. Powertrain system is the key part of pure electric car, and it’s valued by more and more automotive companis and institues. DCT is the most concerned about in the automatic transmission. It has the SS316L-steelof AMT, and it can shift under the power on, so it has better power performance and comfortable adaptability. At present, the researches about pure electric car in our cou ntry are match and optimization on fix ratio reduction gear. No one has studied automation transmission which used in pure electric car, and there has never been a automatic transmission. This essay proposed a two gears DCT automation transmission system applied to pure electric car. And also proposed the CMAC nerve network control to slove the dry clutch control problem.The article’main contents are as follows.(1)Introduced the structure and the development state of the pure electric car powertrain, and made analysis about it. Introduced some transmissions of pure electric car. Also introduced DCT’s structure and principle. Base on the comparing various automation transmissioms, expressed the advantages of DCT. Summarized pure electric car requirements for automatiom transmission. Finally, show the main contents of this article.(2)There are several methods to improve the performance of electric car. For example, improving the performance of the motor, improving the performance of the battery and reducing the mass of car. But our research is match parameters of the prowertrain system to improve the performance. The performance evaluating indicator of pure electric vehicle was presented from two aspects: dynamic property and economic property, and the pure electric vechicle performance needs of our country were given. At the same time, the principle of the gear number and ratio design of transmission system of EV was introduced from two aspects mentioned before. In connection with the pure electric vechicle JF-EV this article involved, reduction gear with fixed ratio and transmission system parameter was designed, and its simulation was done by ADVISOR. The results showed that the performances of electric vechicle with two gears DCT were better in all aspects than electric vehicle with fixed ratio reduction gear. The concept of genetic algorithm was introduced, and the contents and use methods of genetic algorithm tool box. Taking two-gears DCT as example, the use process of genetic algorithm was illustrated, and the ratio of two-gear DCT was optimized combining with ADVISOR. Lastly, certain performances of EV with and without optimation were compared. The result indicated that the travel distance was improved after the ratio of EV had been optimized under the premise of the dynamic property.(3)The dry clutch is the important part of two gears DCT. Controlling the dry clutch’move can make the transmission shift. The research of dry clutch characteristics is the key of control clutch better. Analysised and studied of the dry clutch diaphragm spring load characteristics, and calculated. load characteristics by A-L method. Established the dry clutch torque model about the combination process of dry clutch. Analysised various parameters which effect torque characteristics, including: reverse shock absorber, temperature and wear. And put forward the model of the clutch torque correction method.(4)The principle of actuator of two gears DCT was presented, and the structure and characteristic of proportional flow valve was introduced. The electric control unit of two gears DCT was designed, introducing the function and designed electric circuit. Because of the control system is nonlinear and there are some interferees, the traditional control system is difficult to ensure the control precision. This essay proposed the CMAC nerve network control method to slove the dry clutch control problem. And designed the intelligent controller.(5)The shift control of two gears DCT includes two parts. One is shift rule, another is moving rule of clutch. The evaluating indicator for shifting quality of two-gears DCT was summarized and analysed the effect of different overlap. In this paper, the pure electric car used two parameters type shift rule. According to the characteristics of pure electric car, developed the best economic optimum shift rule and the best power optimum shift rule. Finally, researched the up-shift and down-shift process of two gears DCT, and the SS316L-steelmethod for dry clutch was proposed. While the motor coordination control in shifting process was studied.(6)Analyzed the electric vehicle control system components and functions of the sub-controller of JF-EV. Based on the CAN of JF-EV, developed the data acquisition display software EV-View, and described the software works. Finally, did accelerated test, hill climbing test and shift test. The results showed that, JF-EV electric car meet the dynamic requirements and had a better shift quality SS316L

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Sept4th

SS321 STEEL PLATE

SS321-steel

A bridge’s performance will continue to be degradation once it has been built and put into use. Bridge structure will inevitably be injured by vehicles, wind, earthquake, fatigue, overloading and other natural and man-made factors, which will lead to accumulative damage and sudden injury of the structure or members of the bridge. As a result, the service capacity of the bridge will reduce, which will threaten people’s lives and property safety and bring on huge economic losses. Therefore, we should pay greater attention to bridges’the safety, reliability, durability and normal function in the operation period as well as focusing on building bridges. It is very necessary to establishSS321-steel  health monitoring system to make sure the safety of the bridge. Study on theory and practice of health monitoring of overpass bridge in the city is carried out in the paper combined with national high technology research and development plan (863 project) named‘Research of large range road disaster parameter monitoring and identification and early warning system in seasonal frozen region’, main research work is as follows:1. Optimal placement of static sensors base on damage identificationEmplacing sensors at the bridge structure is the premise of bridge health monitoring. Due to economic factors and structural characteristics, it is impossible and unrealistic to place sensors in all degrees of freedom of the bridge. So an optimization problem on how to place m (m <n) sensors at n degrees of freedom is put forward(SS321).steel It means that how to use limited sensors to obtain the most reliable and most comprehensive health status of the bridge.Setting monitoring sensors in the bridge structural is a prerequisite for achieving health monitoring. An optimal placement method of static sensors is put forward in the paper and corresponding algorithm is written for computing. It is proved that the method is efficient and ascendant through numerical examples, and the optimal placement of sensors using this method is carried out in a special-shaped bridge.2. Static finite element model updating for special-shaped bridgeSolid model of an urban special-shaped overpass bridge is established using finite element method. The model is updated based on uniform design, and the method is validated though real bridge example. Study on theory and practice of model updating based on response surface is carried out and examples are used to test the method. The establishment of an effective finite element model (FEM) for the bridge structure is essential in the health monitoring system of urban grade separation bridge. It inevitably exist inconsistency of response between the FEM and practical structure due to various uncertain factors in the modeling and analysis procedure. Therefore the updating of FEM is necessary. A uniform design-based static model updating method is proposed in this paper, the allowable range of model parameters (the number is m ) is divided into several levels (the number is n ), the model updating method is transformed into a m -factors and n -levels test design. Several groups of combined parameters are selected to conduct test through finite SS321 steelnt calculation based on the principle of uniform design method, and the optimal parameter group is obtained. This method is applied to the model updating of a complicated special-shaped urban grade separation bridge, and a perfect FEM with a good agreement with measured data is obtained. It confirms the feasibility and superiority of this method.Response surface method is a mathematical analysis method combining with mathematical statistics and experimental design. It is proved that it’s practical to update finite element modes of large and complex bridges using response surface method. The accuracy of model updating will improve obviously by using of response surface method only one time when it does not have good results using uniform design method.3. Damage identification for special-shaped bridge based on BP neural network and genetic algorithmThe application of artificial neural network and genetic algorithm in damage identification of bridges is introduced. Damage identification of a real bridge is carried out through the method combined with BP neural network and genetic algorithm.The finite element model of left auxiliary bridge of Qianjin Overpass is built and vulnerable sections of structure are chosen as SS321 research object. The weight and threshold of BP neural network is optimized by genetic algorithm. The individual fitness degree is calculated by fitness function, the optimal individual fitness degree is obtained by crossover and mutation SS321 using genetic algorithm, and the optimal weight and threshold is chosen as initial value of neural network, then damage identification of structure is conducted. Modal frequency and change rate of strain are chosen as input parameters of genetic optimal neural network, and the network is tested by damage identification for single location and multi-location. The simulating results shows that genetic optimal neural network based on modal frequency and SS321on change rate of strain both have strong ability of damage identification, but the genetic optimal neural network based on change rate of strain is better than genetic optimal neural network based on modal frequency. The two kind of network can complement each other and improve the efficiency of damage identification.4. Study on theory and practice of diaphragm beam and special-shaped box girder of urban overpassThe solid model of a six-span prestressed continuous box girder bridge is built in this paper to obtain the stress state of diaphram. Meanwhile, the actual stress distribution form can be measured through embedding vibrational chord strain gauge in the bridge. At last, we put forward a practical and simplified two-step plane member system finite element method, comparative analysis shows that this method is reliable, economical and can also provide valuable reference for the diaphragm design and calculation.Analysis and research on the special-shaped box girder of prestressed bridge which often appears in urban viaducts and overpasses is carried out in the paper. Combined with the practical project, a calculation method of such structure is put forward. The spatial finite element model of the bridge is established to obtain the mechanical behavior of the special-shaped box girder. Strain sensors are buried in the special-shaped box girder during the construction of the bridge, mechanical behavior of the girder can be acquired by way of measuring strain data of the embedded sensors after the completion of the bridge. The finite element model oSS321 steelf the bridge can be modified through the comparison of calculated values with the measured data, thus more accurate value of the internal force and displacement of the practical bridge can be gained. This kind of method has certain reference value for the design of the special-shaped box girder.The research of the paper plays an important role in exploration results in both theoretical and experimental methods of health monitoring of urban overpass. The results of the research have practical significance which lay a solid foundation for the designing and establishing of health monitoring systemSS321

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Sept4th

SS904L-steel

SS904L steel

With the increment of urban vehicle ownership, vehicle handling stability and activesafety issues received extensive attention. Active safety control systems can improvethe handling stability of vehicle e?ectively and then avoid tra?c accidents. However,on the premise that we can access the vehicle running states accurately, which includethe longitudinal vehicle velocity, the lateral vehicle velocity, the sideslip angle, the yawrate and other states information, then the contSS904L steelrol logic of these vehicle active safetysystems can be work e?ectively. At present, the vehicle states that mentioned abovecan not be measured directly by the onboard sensors on the mass production vehicles.It has become bottleneck issues and limited the development of vehicle active safetycontrol systems because the lack of vehicle states information. With the developmentof the estimation theory, the vehicleSS904L steel states estimation become focus problems using themeasured information by the onboard sensors which has been equipped on the massproduction vehicle. Meanwhile, the vehicle states estimation is a challenging work becausethe environment change rapidly in the vehicle running and the road situation is extremelycomplex, in addition, there are calibration errors and temperature drift errors in theonboard sensors. The longitudinal vehicle velocity and lateral vehicle velocity are theessential information to be estimated among the numerous vehicle states for the activesafety systems. Therefore, the longitudinal vehicle velocity and lateral vehicle velocityhave important theoretical and practical significance.The objective of this paper is to present reliable and real-time nonlinear observermethod for vehicle velocity estimation for the longitudinal vehicle velocity and lateralSS904L steelvehicle velocity, which can not be measured directly in the active safety control problem.The experiments are carried out to validate the estimation results on the hardware-in-the-loop simulation platform, and then the hardware implementation scheme of nonlinearobserver is discussed.For the nonlinear dynamic characteristics shown in the vehicle running, A nonlinearfull-order observer with less measurement information is proposed for vehicle velocity es- timation based on the vehicle dynamic model and Uni-Tire model for longitudinal slipand lateral slip. The computed acceleration information using Uni-Tire model replace theonboard sensor information after identification the Uni-Tire model for longitudinal slipand lateral slip. The longitudinal velocity, lateral velocity and yaw rate of the vehicleare estimated by the observer using the information of vehicle states such as wheel ro-tational speed, the steering wheel angle and lateral acceleration which are measured byon-board sensors. The stability of the observer is analyzed using the theory of input-to-state stability(ISS), furthermore, the condition which the observer gain stratified is got.The nonlinear full-order observer has simple structure, good real time performance andcan be realized easily.For the complex structure, the state coupled with each other and the strong nonlinear-ity of vehicle systems, a nonlinear reduced-order observer method with less computationis presented for the longitudinal vehicle velocity and lateral vehicle velocity estimation,where the impact on vehicle dynamics is considered, which is caused by the changes ofCoG in the vehicle running. The yaw acceleration is chosen as the correction informationfor longitudinal vehicle velocity and lateral vehicle velocity estimation by analyzing thedynamic relationship between yaw rate and vehicle velocity. The condition of nonlinearobserver gain satisfied is obtained under the situation that the reduce-order observer isISS, and the condition is transform into LMIs using the Polytopic model description. Thesolving steps of reSS904L steelduce order observer is received by analyzing the relationship betweenobserver parameters, error decay rate and steady state error. The simulation study for es-timation results of reduced-order observer is carried out in the conventional condition andcritical condition, and the real-time experiments are carried out to validate the real-timeperformance.In order to avoid computational burden caused by complex tire model and improvethe calculation speed of the vehicle velocities observer, the tire model is received whichis built using MAP and the mechanism model description. The nonlinear cascaded ob-server method is presented for vehicle longitudinal velocity and lateral velocity estimationconsidering coriolis acceleration as disturbance of longitudinal vehicle velocity observer.we first used wheel rotational speed build longitudinal vehicle velocity observer, and thenthe estimated longitudinal vehicle velocity is used as input to estimated lateral vehiclevelocity. The longitudinal vehicle velocity observer and lateral vehicle velocity observercomposed of cascade structure. The ISS theory is used to analyse the stability of the ob-server and the condition which observer gain satisfied is got. Finally, in order to determinethe range of the observer gain and parameters, the performance function for nonlinearcascade observSS904L steeler is proposed, and the randomized algorithms is employed to discuss the range of the observer gain and parameters using Monte Carlo experiments.In order to validate the effectiveness of the nonlinear vehicle velocity observer method,the experiment must be carried out. The nonlinear vehicle velocity observer is validatedon the HiL platform which is builded based on xPC-Target real-time structure and vehi-cle dynamics software by operating the external steering wheel angle, acceleration pedaland brake pedal. Based on this, the FPGA/SOPC scheme is proposed for the hard-ware implementation of nonlinear veSS904L steelhicle velocity observer to satisfy the requirement ofminiaturization, real-time performance. The experimental validation is carried out for theeffectiveness and real-time performance base on dSPACE real time platform and FPGAexploited board and better experiment result is obtained.The formulation processes and the proof of mentioned approaches are presented indetail in this thesis. Moreover, in order to validate the efficiency of the proposed ap-proaches, we give simulation results for each approach, which is discussed from systemmodeling, vehicle velocity observer design, observer parameter choosing, simulation andexperiments. The simulation and experiments results indicate that estimation methodeffects with the proposed approaches are satisfactory.Deeper research work neSS904L steeleds to be done since some problems are still remain to besolved, for example, the roll motion and aerodynamic are omitted during the vehiclemodeling, so there exist some modeling errors, It requires improving the accuracy ofvehicle dynamics model constantly in future work. As the wheel speed can be measureddirectly by onboard sensors and it can be modeled by the drive torque and brake torque, wecan try to use the 7 degrees of freedom vehicle dynamics model to design the reduce-orderobserver. We can design some hardware accelerators to increase the computation speedin the research of FPGA/SOPC hardware implementation of nonlinear vehicle velocityobserver. In the hardware platform, only the hardware of driver manoeuvre is embeddedat present, how to embed more external sensor information which is useful for vehiclestates estimation, it is need to be further researchSS904L steel

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