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Exploration of Energy-Saving Technologies in Building Electrical System Design
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作者 Yong Zhang 《Journal of Electronic Research and Application》 2024年第4期28-33,共6页
Green energy conservation is the mainstream trend in the current development of the construction industry.The application of energy-saving technology in building electrical system design can effectively reduce energy ... Green energy conservation is the mainstream trend in the current development of the construction industry.The application of energy-saving technology in building electrical system design can effectively reduce energy consumption,avoid unnecessary energy consumption,and truly achieve energy conservation and environmental protection.Based on this,the article elaborates on the principles of energy-saving design in building electrical systems,and actively explores the application of energy-saving technologies from different perspectives such as optimizing power supply and distribution system design,adopting high-efficiency energy-saving lighting equipment,applying renewable energy,promoting smart home technology,and improving the efficiency of building electrical equipment. 展开更多
关键词 Building electrical system design Energy-saving technology
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Teaching Reform and Practice of Embedded System Design Based on Outcome-Based Education
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作者 Tao Zhang Xiangwu Deng 《Journal of Contemporary Educational Research》 2024年第3期13-18,共6页
Embedded system design is the core course of the telecommunication major in engineering universities,which combines software and hardware through embedded development boards.Aiming at the problems existing in traditio... Embedded system design is the core course of the telecommunication major in engineering universities,which combines software and hardware through embedded development boards.Aiming at the problems existing in traditional teaching,this paper proposes curriculum teaching reform based on the outcome-based education(OBE)concept,including determining course objectives,reforming teaching modes and methods,and improving the curriculum assessment and evaluation system.After two semesters of practice,this method not only enhances students’learning initiative but also improves teaching quality. 展开更多
关键词 Embedded system design Outcome-based education(OBE) Teaching reform
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THE BOUNDEDNESS OF OPERATORS ON WEIGHTED MULTI-PARAMETER LOCAL HARDY SPACES
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作者 丁卫 汤彦 朱月萍 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期386-404,共19页
Though atomic decomposition is a very useful tool for studying the boundedness on Hardy spaces for some sublinear operators,untill now,the boundedness of operators on weighted Hardy spaces in a multi-parameter setting... Though atomic decomposition is a very useful tool for studying the boundedness on Hardy spaces for some sublinear operators,untill now,the boundedness of operators on weighted Hardy spaces in a multi-parameter setting has been established only by almost orthogonality estimates.In this paper,we mainly establish the boundedness on weighted multi-parameter local Hardy spaces via atomic decomposition. 展开更多
关键词 weighted multi-parameter local Hardy spaces atomic decomposition boundedness inhomogeneous Journéclass
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A Solar Energy System Design for Green Hydrogen Production in South-Western Nigeria, Lagos State, Using HOMER & ASPEN
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作者 Wilson Fidelis Ekpotu Joseph Taiwo Akintola +1 位作者 Martins Chineme Obialor Philemon Chukwuebuka Udom 《Open Journal of Optimization》 2023年第2期72-97,共26页
Solar system design for green hydrogen production has become the most prominent renewable energy research area, and this has also actively fueled the desire to achieve net-zero emissions. Hydrogen is a promising energ... Solar system design for green hydrogen production has become the most prominent renewable energy research area, and this has also actively fueled the desire to achieve net-zero emissions. Hydrogen is a promising energy carrier because it possesses more energy capacity than fossil fuels and the abundant nature of renewable energy systems can be utilized for green hydrogen production. However, the design of an optimized electrical energy system required for hydrogen production is crucial. Solar energy is indeed beneficial for green hydrogen production and this research designed, discussed, and provided high-level research on HOMER design for green hydrogen production and deployed the energy requirement with ASPEN Plus to optimize the energy system, while also incorporating fuzzy logic and PID control approaches. In addition, a promising technology with a high potential for renewable hydrogen energy is the proton exchange membrane (PEM) electrolyzer. Since its cathode (hydrogen electrode) may be operated over a wide range of pressure, a control process must be added to the system in order for it to work dynamically efficiently. This system can be characterized as an analogous circuit that consists of a resistor, capacitor, and reversible voltage. As a result, this research work also explores the Fuzzy-PID control of the PEM electrolysis system. Both the PID and Fuzzy Logic control systems were simulated using the control simulation program Matlab R2018a, which makes use of Matlab script files and the Simulink environment. Based on the circuit diagram, a transfer function that represents the mathematical model of the plant was created, and the PEM electrolysis control system is determined to be highly significant and applicable to the two control systems. The PI controller, however, has a 30.8% overshoot deficit, but when the fuzzy control system is compared to the PID controller, it is found that the fuzzy control system achieves stability more quickly, demonstrating its benefit over PID. 展开更多
关键词 Homer Solar design Solar Energy Renewable Energy Green Hydrogen Production Fuzzy Logic HOMER
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CAutoCSD-Evolutionary Search and Optimisation Enabled Computer Automated Control System Design 被引量:1
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作者 Kiam Heong Ang Gregory C.Y. +1 位作者 Kay Chen Tan Hiroshi Kashiwagi 《International Journal of Automation and computing》 EI 2004年第1期76-88,共13页
This paper attempts to set a unified scene for various linear time-invariant (LTI) control system design schemes, by transforming the existing concept of “computer-aided control system design” (CACSD) to novel “com... This paper attempts to set a unified scene for various linear time-invariant (LTI) control system design schemes, by transforming the existing concept of “computer-aided control system design” (CACSD) to novel “computer-automated control system design” (CAutoCSD). The first step towards this goal is to accommodate, under practical constraints, various design objectives that are desirable in both time and frequency domains. Such performance-prioritised unification is aimed at relieving practising engineers from having to select a particular control scheme and from sacrificing certain performance goals resulting from pre-commitment to such schemes. With recent progress in evolutionary computing based extra-numeric, multi-criterion search and optimisation techniques, such unification of LTI control schemes becomes feasible, analytical and practical, and the resultant designs can be creative. The techniques developed are applied to, and illustrated by, three design problems. The unified approach automatically provides an integrator for zero-steady state error in velocity control of a DC motor, and meets multiple objectives in the design of an LTI controller for a non-minimum phase plant and offers a high-performance LTI controller network for a non-linear chemical process. 展开更多
关键词 Linear time invariant (LTI) proportional plus integral plus derivative (PID) control system design (CSD) COMPUTER aided control system design (CACSD) performance index genetic algorithms (GA) evolutionary computation (EC) process control r
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ON BOUNDEDNESS OF SOLUTIONS OFIMPULSIVE INTEGRO-DIFFERENTIAL SYSTEMSWITH FIXED MOMENTS OF IMPULSE EFFECTS 被引量:12
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作者 傅希林 张立琴 《Acta Mathematica Scientia》 SCIE CSCD 1997年第2期219-229,共11页
Several boundedness criteria for the impulsive integro-differential systems with fixed moments of impulse effects are established, employing the method of Lyapunov functions and Razumikhin technique.
关键词 boundedness impulsive integro-differential systems Lyapunov functions
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BOUNDEDNESS OF THE HIGHER-DIMENSIONAL QUASILINEAR CHEMOTAXIS SYSTEM WITH GENERALIZED LOGISTIC SOURCE 被引量:6
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作者 Qingquan TANG Qiao XIN Chunlai MU 《Acta Mathematica Scientia》 SCIE CSCD 2020年第3期713-722,共10页
This article considers the following higher-dimensional quasilinear parabolic-parabolic-ODE chemotaxis system with generalized Logistic source and homogeneous Neumann boundary conditions{ut=∇⋅(D(u)∇u)−∇⋅(S(u)∇v)+f(u),... This article considers the following higher-dimensional quasilinear parabolic-parabolic-ODE chemotaxis system with generalized Logistic source and homogeneous Neumann boundary conditions{ut=∇⋅(D(u)∇u)−∇⋅(S(u)∇v)+f(u),x∈Ω,t>0 vt=Δv+w−v,x∈Ω,t>0,wt=u−w,x∈Ω,t>0,in a bounded domainΩ⊂R^n(n≥2)with smooth boundary ∂Ω,where the diffusion coefficient D(u)and the chemotactic sensitivity function S(u)are supposed to satisfy D(u)≥M1(u+1)^−αand S(u)≤M2(u+1)^β,respectively,where M1,M2>0 and α,β∈R.Moreover,the logistic source f(u)is supposed to satisfy f(u)≤a−μu^γ with μ>0,γ≥1,and a≥0.Asα+2β<γ−1+2γ/n,we show that the solution of the above chemotaxis system with sufficiently smooth nonnegative initial data is uniformly bounded. 展开更多
关键词 Chemotaxis system logistic source global solution boundedness
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Uniformly ultimate boundedness for discontinuous systems with time-delay 被引量:1
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作者 慕小武 丁志帅 程桂芳 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2011年第9期1187-1196,共10页
The uniformly ultimate boundedness of discontinuous systems with time-delay in the sense of Filippov solutions is discussed.Based on the Lyapunov-Krasovskii functional,the Lyapunov theorem for the globally strongly un... The uniformly ultimate boundedness of discontinuous systems with time-delay in the sense of Filippov solutions is discussed.Based on the Lyapunov-Krasovskii functional,the Lyapunov theorem for the globally strongly uniformly ultimate boundedness of retarded discontinuous systems is presented.Furthermore,the result is applied to a class of mechanical systems with a retarded discontinuous friction item. 展开更多
关键词 Filippov solution uniformly ultimate boundedness discontinuous system ratarded system
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Motion/Posture Modeling and Simulation Verification of Physically Handicapped in Manufacturing System Design 被引量:3
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作者 FU Yan LI Shiqi CHEN Gwen-guo 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2013年第2期225-231,共7页
Non-obstacle design is critical to tailor physically handicapped workers in manufacturing system. Simultaneous consideration of variability in physically disabled users, machines and environment of the manufacturing s... Non-obstacle design is critical to tailor physically handicapped workers in manufacturing system. Simultaneous consideration of variability in physically disabled users, machines and environment of the manufacturing system is extremely complex and generally requires modeling of physically handicapped interaction with the system. Most current modeling either concentrates on the task results or functional disability. The integration of physical constraints with task constraints is far more complex because of functional disability and its extended influence on adjacent body parts. A framework is proposed to integrate the two constraints and thus model the specific behavior of the physical handicapped in virtual environment generated by product specifications. Within the framework a simplified model of physical disabled body is constructed, and body motion is generated based on 3 levels of constraints(effecter constraints, kinematics constraints and physical constraints). The kinematics and dynamic calculations are made and optimized based on the weighting manipulated by the kinematics constraints and dynamic constraints. With object transferring task as example, the model is validated in Jack 6.0. Modelled task motion elements except for squatting and overreaching well matched with captured motion elements. The proposed modeling method can model the complex behavior of the physically handicapped by integrating both task and physical disability constraints. 展开更多
关键词 physical handicapped motion/posture modeling manufacturing system design
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BOUNDEDNESS AND ASYMPTOTIC STABILITY IN A PREDATOR-PREY CHEMOTAXIS SYSTEM WITH INDIRECT PURSUIT-EVASION DYNAMICS 被引量:1
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作者 Shuyan QIU Chunlai MU Hong YI 《Acta Mathematica Scientia》 SCIE CSCD 2022年第3期1035-1057,共23页
This work explores the predator-prey chemotaxis system with two chemicals {u_(t) = Δu + ∇ ・ (u∇v) + μ_(1)u(1 − u − α_(1)w), x ∈ Ω, t > 0,v_(t )= Δv −α_(1)v + β_(1)w, x ∈ Ω, t > 0,w_(t) = Δw − ξ∇ ・ (w... This work explores the predator-prey chemotaxis system with two chemicals {u_(t) = Δu + ∇ ・ (u∇v) + μ_(1)u(1 − u − α_(1)w), x ∈ Ω, t > 0,v_(t )= Δv −α_(1)v + β_(1)w, x ∈ Ω, t > 0,w_(t) = Δw − ξ∇ ・ (w∇z) + μ_(2)w(1 + α_(2)u − w), x ∈ Ω, t > 0,z_(t) =Δz −α_(2)z +β_(2)u, x ∈ Ω, t > 0, in an arbitrary smooth bounded domainΩ■R^(n) under homogeneous Neumann boundary conditions.The parameters in the system are positive.We first prove that if n≤3,the corresponding initial-boundary value problem admits a unique global bounded classical solution,under the assumption thatχ,ξ,μ_(i),a_(i),α_(i) andβ_(i)(i=1,2)satisfy some suitable conditions.Subsequently,we also analyse the asymptotic behavior of solutions to the above system and show that·when a_(1)<1 and bothμ1/χ^(2) andμ2/ξ^(2) are sufficiently large,the global solution(u,v,w,z)of this system exponentially converges to(1-a_(1)/1+a_(1)a_(2),β_(1)(1+a_(2))/α_(1)(1+a_(1)a_(2)),1+a_(2)/1+a_(1)a_(2),β_(2)(1-a_(1))/α_(2)(1+a_(1)a_(2)))as t→∞;·when a1>1 andμ_(2)/ξ_(2) is sufficiently large,the global bounded classical solution(u,v,w,z)of this system exponentially converges to(0,α_(1)/β_(1),1,0)as t→∞;·when a1=1 andμ_(2)/ξ_(2) is sufficiently large,the global bounded classical solution(u,v,w,z)of this system polynomially converges to(0,α_(1)/β_(1),1,0)as t→∞. 展开更多
关键词 CHEMOTAXIS PREDATOR-PREY boundedness STABILIZATION
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Data Driven Uncertainty Evaluation for Complex Engineered System Design 被引量:1
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作者 LIU Boyuan HUANG Shuangxi +4 位作者 FAN Wenhui XIAO Tianyuan James HUMANN LAI Yuyang JIN Yan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第5期889-900,共12页
Complex engineered systems are often difficult to analyze and design due to the tangled interdependencies among their subsystems and components. Conventional design methods often need exact modeling or accurate struct... Complex engineered systems are often difficult to analyze and design due to the tangled interdependencies among their subsystems and components. Conventional design methods often need exact modeling or accurate structure decomposition, which limits their practical application. The rapid expansion of data makes utilizing data to guide and improve system design indispensable in practical engineering. In this paper, a data driven uncertainty evaluation approach is proposed to support the design of complex engineered systems. The core of the approach is a data-mining based uncertainty evaluation method that predicts the uncertainty level of a specific system design by means of analyzing association relations along different system attributes and synthesizing the information entropy of the covered attribute areas, and a quantitative measure of system uncertainty can be obtained accordingly. Monte Carlo simulation is introduced to get the uncertainty extrema, and the possible data distributions under different situations is discussed in detail The uncertainty values can be normalized using the simulation results and the values can be used to evaluate different system designs. A prototype system is established, and two case studies have been carded out. The case of an inverted pendulum system validates the effectiveness of the proposed method, and the case of an oil sump design shows the practicability when two or more design plans need to be compared. This research can be used to evaluate the uncertainty of complex engineered systems completely relying on data, and is ideally suited for plan selection and performance analysis in system design. 展开更多
关键词 complex engineered system design UNCERTAINTY data-driven evaluation Monte Carlo simulation
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Stability and boundedness in terms of two measures for nonlinear impulsive control systems
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作者 Qiang XI 《控制理论与应用(英文版)》 EI 2009年第3期243-247,共5页
In this paper we study stability and boundedness in terms of two measures for impulsive control systems. By using variational Lyapunov method, a new variational comparison principle and some criteria on stability and ... In this paper we study stability and boundedness in terms of two measures for impulsive control systems. By using variational Lyapunov method, a new variational comparison principle and some criteria on stability and boundedness are obtained. An example is presented to illustrate the efficiency of proposed result. 展开更多
关键词 STABILITY boundedness Impulsive control systems Variational Lyapunov method Two measures
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A New Uniformly Ultimate Boundedness Criterion for Discrete-Time Nonlinear Systems
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作者 Zhishuai Ding Guifang Cheng 《Applied Mathematics》 2011年第11期1323-1326,共4页
A new type criterion of globally uniformly ultimate boundedness for discrete-time nonlinear systems is introduced. In classical Lyapunov theory about globally uniformly ultimate boundedness, Lyapunov function is assum... A new type criterion of globally uniformly ultimate boundedness for discrete-time nonlinear systems is introduced. In classical Lyapunov theory about globally uniformly ultimate boundedness, Lyapunov function is assumed to be positive definite and its difference at the every latter moment and the former moment is negative definite. In this paper the condition of difference of Lyapunov function is relaxed. Under the relaxed condition, the result of this paper can be considered as the extension of the classical Lyapunov theory about uniformly ultimate boundedness. 展开更多
关键词 UNIFORMLY ULTIMATE boundedness LYAPUNOV Function DISCRETE-TIME Nonlinear systems
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BOUNDEDNESS OF SOLUTIONS AND EXISTENCEOF LIMIT CYCLES FOR A NONLINEAR SYSTEMOF DIFFERENTIAL EQUATIONS 被引量:6
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作者 黄立宏 陈明博 《Acta Mathematica Scientia》 SCIE CSCD 1998年第1期113-120,共8页
In this paper, author obtain sufficient conditions for the boundedness of solutions and the existence of limit cycles of the nonlinear differential system dx/dt = p(y), dy/dt = -q(y)h(x,y) - g(x) without the tradition... In this paper, author obtain sufficient conditions for the boundedness of solutions and the existence of limit cycles of the nonlinear differential system dx/dt = p(y), dy/dt = -q(y)h(x,y) - g(x) without the traditional assumptions 'h(x,y) greater than or equal to 0 for \x\ sufficiently large' and 'integral(0)(+/-infinity) g(x)dx = +infinity'. 展开更多
关键词 nonlinear differential system boundedness EXISTENCE limit cycle
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Control system design of hybrid fuel cell city bus 被引量:1
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作者 Li Jianqiu Xu Liangfei Hua Jianfeng Li Xiangjun Ouyang Minggao 《Engineering Sciences》 EI 2010年第1期84-91,共8页
This paper introduced the design of the hybrid powertrain of the Fuel Cell City Bus demonstrated in 2008 Beijing Olympic Games. The configuration of the hybrid fuel cell powertrain was introduced. The safety of hydrog... This paper introduced the design of the hybrid powertrain of the Fuel Cell City Bus demonstrated in 2008 Beijing Olympic Games. The configuration of the hybrid fuel cell powertrain was introduced. The safety of hydrogen storage and delivery system, the hydrogen leakage alarm system were developed. The real-time distributed control and diagnosis system based on the Time Trigger Controller Area Network (TTCAN) with 10 ms basic control period was developed. The concept and implementation of processor (or controller) monitor and process (or task) monitor technique based on the TYCAN were applied in this paper. The fault tolerant control algorithm of the fuel cell engine and the battery man- agement system were considered. The demonstration experience verified that the fault tolerant control was very important for the fuel cell city bus. 展开更多
关键词 hybrid fuel cell city bus time triggered controller area network control system design
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EXISTENCE AND BOUNDEDNESS OF SOLUTIONS FOR SYSTEMS OF QUASILINEAR ELLIPTIC EQUATIONS
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作者 Abdelkrim MOUSSA OUI Jean VELIN 《Acta Mathematica Scientia》 SCIE CSCD 2021年第2期397-412,共16页
This article sets forth results on the existence and boundedness of solutions for quasilinear elliptic systems involving p-Laplacian and q-Laplacian operators.The approach combines Schaefer's fixed point as well a... This article sets forth results on the existence and boundedness of solutions for quasilinear elliptic systems involving p-Laplacian and q-Laplacian operators.The approach combines Schaefer's fixed point as well as Moser's iteration procedure. 展开更多
关键词 P-LAPLACIAN Schaefer's fixed point Besov and Sobolev spaces boundedness REGULARITY
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The Boundedness of Nonlinear Control Systems
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作者 Zhao Wen-yu 《九江学院学报(社会科学版)》 1986年第5期1-6,共6页
In this paper we consider nonlinear control sysfemdx/dt=A(t)x+B(t)f(x),(1)Where x(t)∈Rn is the state vector,A(t)=(aij(t))n×nis the System matrix,B(t),an nxr time-varying matrix,is the input matri... In this paper we consider nonlinear control sysfemdx/dt=A(t)x+B(t)f(x),(1)Where x(t)∈Rn is the state vector,A(t)=(aij(t))n×nis the System matrix,B(t),an nxr time-varying matrix,is the input matrix;f(x)∈Rr is nonlinearvector function,and A(t),B(t)∈c[t0,∞),f(x)∈c[x0,∞)Here we are to discuss thc boundedness of system(1)in various cases ofmatrix A(t),and the following results shall be obtained.In this paper,weshall use the results of Bihari and other authors. 展开更多
关键词 boundedness satisfied LIAPUNOV proof UNIQUENESS INEQUALITY GENERALIZATION inverse SCALAR Bellman
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Automatic lifting system design and application of large load powered support test rig
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作者 LIU Xin-ke 《Journal of Coal Science & Engineering(China)》 2012年第4期428-431,共4页
This paper presented a design of an automatic lifting system. It is used for large load powered support and improves the old method wherein powered support lifting depends on manual control. This system applies a high... This paper presented a design of an automatic lifting system. It is used for large load powered support and improves the old method wherein powered support lifting depends on manual control. This system applies a high accuracy gear shunt motor to match the flow for 4 lifting cylinders, and also allocates bypass throttles to realize automatic lifting. Through the dis- placement sensor feedback the height deviation among 4 lifting cylinders during the whole lifting process, when the deviation is up to the sitting value, the corresponding bypass throttle is operated immediately to reduce the deviation, so that the moving platform of the powered support would not be stuck. Through real application, it is shown that this system can realize automatic lifting of powered support; the lifting speed is controlled between 5 and 10 mm/s, and the final aligning accuracy is up to 1 mm. 展开更多
关键词 powered support automatic lift hydraulic system design test rig large load
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Electromagnetic System Design and Visual Simulation
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作者 ZHANGJing-shu CHENDe-gui NIUChun-ping 《Computer Aided Drafting,Design and Manufacturing》 2004年第1期36-41,共6页
An electromagnet design system is developed using Visual C++ language and OpenGL technology to visualize parametric 3D model. The system consists of primary design, optimization design, dynamic and static characterist... An electromagnet design system is developed using Visual C++ language and OpenGL technology to visualize parametric 3D model. The system consists of primary design, optimization design, dynamic and static characteristics, and visual simulation. All empirical parameters and curves used in design process are stored in database. Through human-computer interactions, an electromagnetic system can be designed conveniently with the results and characteristics curves displayed in graphic model. Using this system can greatly shorten the process of product design, and the results satisfy technical requirements. 展开更多
关键词 visualization technology electromagnetic system design database technology optimization design
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Financial System Design and Firm Investment in Malaysian Listed Firms
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作者 Masturah Ma'in Abdul Ghafar Ismail 《Journal of Modern Accounting and Auditing》 2011年第1期14-30,共17页
This paper investigates the impact of financial system design on investment. It is aimed to provide additional empirical evidence based on the original paper by Demirguc-Kunt and Maksimovic (2002). The firm-level da... This paper investigates the impact of financial system design on investment. It is aimed to provide additional empirical evidence based on the original paper by Demirguc-Kunt and Maksimovic (2002). The firm-level data of Malaysian companies between 2000 and 2007 are used. This paper also extends the previous literatures by using a panel data methodology, applying a random-effects estimator. The findings show that: First, the growth investment of firms are positively related to the development of the banking system but negatively related to the capital market. These firms substitute equity for debt associated with an increase in stock market activity (more long-term financing) and debt for equity in the presence of an increase in banking activity (less long-term financing). Second, the internal growth financing, short-term growth financing and long-term growth financing have shown a significant impact on growth investment by firms. It implies that these financing constraints are complements to the development of banking system and stock market activity. Therefore, well-developed stock markets facilitate long-term financing, whereas a well-developed banking sector facilitates short-term financing. It is recommended that policy makers stress more on banking system for short-term financing and capital market for long-term financing. 展开更多
关键词 financial system design external financing firm investment
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