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Effects of Joint Controller on Analytical Modal Analysis of Rotational Flexible Manipulator 被引量:7
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作者 CHU Ming ZHANG Yanheng +1 位作者 CHEN Gang SUN Hanxu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第3期460-469,共10页
Modal analysis is a fundamental and important task for modeling and control of the flexible manipulator. However, almost all of the traditional modal analysis methods view the flexible manipulator as a pure mechanical... Modal analysis is a fundamental and important task for modeling and control of the flexible manipulator. However, almost all of the traditional modal analysis methods view the flexible manipulator as a pure mechanical structure and neglect feedback action of joint controller. In order to study the effects of joint controller on the modal analysis of rotational flexible manipulator, a closed-loop analytical modal analysis method is proposed. Firstly, two exact boundary constraints, namely servo feedback constraint and bending moment constraint, are derived to solve the vibration partial differential equation. It is found that the stiffness and damping gains of joint controller are both included in the boundary conditions, which lead to an unconventional secular term. Secondly, analytical algorithm based on Ritz approach is developed by using Laplace transform and complex modal approach to obtain the natural frequencies and mode shapes. And then, the numerical simulations are performed and the computational results show that joint controller has pronounced influence on the modal parameters: joint controller stiffness reduces the natural frequency, while joint controller damping makes the shape phase non-zero. Furthermore, the validity of the presented conclusion is confirmed through experimental studies. These findings are expected to improve the performance of dynamics simulation systems and model-based controllers. 展开更多
关键词 flexible manipulator analytical modal analysis boundary constraints joint controller
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Analytical modeling of piezoelectric meta-beams with unidirectional circuit for broadband vibration attenuation
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作者 Jiawei MAO Hao GAO +2 位作者 Junzhe ZHU Penglin GAO Yegao QU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第10期1665-1684,共20页
Broadband vibration attenuation is a challenging task in engineering since it is difficult to achieve low-frequency and broadband vibration control simultaneously.To solve this problem,this paper designs a piezoelectr... Broadband vibration attenuation is a challenging task in engineering since it is difficult to achieve low-frequency and broadband vibration control simultaneously.To solve this problem,this paper designs a piezoelectric meta-beam with unidirectional electric circuits,exhibiting promising broadband attenuation capabilities.An analytical model in a closed form for achieving the solution of unidirectional vibration transmission of the designed meta-beam is developed based on the state-space transfer function method.The method can analyze the forward and backward vibration transmission of the piezoelectric meta-beam in a unified manner,providing reliable dynamics solutions of the beam.The analytical results indicate that the meta-beam effectively reduces the unidirectional vibration across a broad low-frequency range,which is also verified by the solutions obtained from finite element analyses.The designed meta-beam and the proposed analytical method facilitate a comprehensive investigation into the distinctive unidirectional transmission behavior and superb broadband vibration attenuation performance. 展开更多
关键词 broadband vibration attenuation efficient closed-form analytical solution electromechanical coupling piezoelectric material vibration control
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Analytical Analysis on the Structure of a Typical Fuzzy On - Off Controller
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作者 丁永生 任立红 邵世煌 《Journal of China Textile University(English Edition)》 EI CAS 1999年第1期20-22,共3页
The analytical structure of a typical fuzzy on - off controller that employs three or more triangular Input fuzzy sets, Zadeh fuzzy logic AND operator, fuzzy rules with singleton output fuzzy sets, and the centriod de... The analytical structure of a typical fuzzy on - off controller that employs three or more triangular Input fuzzy sets, Zadeh fuzzy logic AND operator, fuzzy rules with singleton output fuzzy sets, and the centriod defuzzifier is Investigated in this paper. The analytical expressions of the variable gains of the fuzzy controller are derived. The resulting explicit structure shows that the fuzzy controller is accurately a nonlinear PD - like controller with gains continuously changing with system output in different regions of input space. 展开更多
关键词 analytical STRUCTURE FUZZY control ORE - OFF control PD control.
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Analytical Structures of Typical Takagi-Sugeno Fuzzy PID Gain Scheduling Controllers
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作者 丁永生 任立红 邵世煌 《Journal of China Textile University(English Edition)》 EI CAS 1999年第3期5-9,共5页
The analytical structure of a class of typical Takagi Sugeno (TS) fuzzy controllers is revealed in this paper.The TS fuzzy controllers consist of three or more trapezoidal input fuzzy sets, Zadeh fuzzy logic AND opera... The analytical structure of a class of typical Takagi Sugeno (TS) fuzzy controllers is revealed in this paper.The TS fuzzy controllers consist of three or more trapezoidal input fuzzy sets, Zadeh fuzzy logic AND operator,fuzzy rules with linear consequent, and the centriod defuzzifier. The TS fuzzy controllers are proved to be accurately nonlinear PID controllers with gains continuously changing with process output. The analytical expressions of the variable gains of the TS fuzzy controllers are derived and their mathematical characteristics including the bounds and geometrical shape of the gain variation are analyzed. The resulting explicit structures show that the TS fuzzy controllers are inherently nonlinear PID gain scheduling controllers with variable gains in different regions of input space. 展开更多
关键词 analytical structure TS fuzzy controllers PID controllers GAIN scheduling controllers .
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Analytical Methods in Quality Control of Scientific Publications
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作者 Ilia Brondz 《American Journal of Analytical Chemistry》 2012年第6期443-447,共5页
Plagiarism, fake or even falsified presentation has become a major plague for scientific publications. This paper is a response to personal appeal by David JW Lane the Editor-in-Chief of Research and Reports in Biodiv... Plagiarism, fake or even falsified presentation has become a major plague for scientific publications. This paper is a response to personal appeal by David JW Lane the Editor-in-Chief of Research and Reports in Biodiversity Studies to support and promote the international author standards as developed by COPE for authors and editors-in-chief posted to me April 3rd 2012 (International standards for editors and authors http://www.dovepress.com/rrbscope.t9699812). As corresponding author for more than 100 scientific papers, dozens of scientific reviews, several chapters in scientific books, and author and editor of a book Historical Overview of Chromatography and Related Techniques in Analysis of Antimalarial Drug Primaquine, and as a reviewer of Journal of Chromatography, Journal of Chromatography A, Journal of Chromatography B: Biomedical Sciences and Applications, Lipids, Journal of General Microbiology, Journal of Clinical Microbiology, Journal of Microbiological Methods, Oral Microbiology and Immunology, Analytica Chimica Acta, Mycological Research and Journal of Pharmaceutical and Biomedical Analysis, and member of editorial board of Electronic Components and Systems, American Journal of Analytical Chemistry, ISRN Chromatography and Open Journal of Clinical Diagnostics I was adhered to a new ethical and moral standards in scientific publications. The presented paper is an example of use the analytical methods in visualizing of plagiarism and falsification in the published scientific literature. It is obvious that some of scientific publications need careful quality control. Some papers should have been rejected but were not. These papers clearly pollute the field of scientific information. It is not always easy to demonstrate inappropriate presentation even when many supporting facts are available. The facts should be obvious;there should be no hesitation about the quality or value of a paper presented for consideration to be published. Plagiarism is most common and harmful phenomenon in scientific publications. The plagiarism is based on an original discovery or reproduction of the results from the other authors. The analytical methods used in the quality control of the data can disclose plagiarism. An example is the publication under scrutiny “Applications of GC-EI-MS for the Identification of Positional Isomer in Primaquine, an Antimalarial Drug” by Dongre et al. (2005) Journal of Pharmaceutical and Biomedical Analysis 39, No. 1-2, 111-116. 展开更多
关键词 analytical METHODS in QUALITY control 13C NMR SPECTROSCOPY PRIMAQUINE Quinocide
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CONSTANT ELASTICITY OF VARIANCE MODEL AND ANALYTICAL STRATEGIES FOR ANNUITY CONTRACTS 被引量:2
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作者 肖建武 尹少华 秦成林 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第11期1499-1506,共8页
The constant elasticity of variance(CEV) model was constructed to study a defined contribution pension plan where benefits were paid by annuity. It also presents the process that the Legendre transform and dual theo... The constant elasticity of variance(CEV) model was constructed to study a defined contribution pension plan where benefits were paid by annuity. It also presents the process that the Legendre transform and dual theory can be applied to find an optimal investment policy during a participant's whole life in the pension plan. Finally, two explicit solutions to exponential utility function in the two different periods (before and after retirement) are revealed. Hence, the optimal investment strategies in the two periods are obtained. 展开更多
关键词 defined contribution pension plan stochastic optimal control CEV model Legendre transform analytical strategy
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Comparative Analysis of Tunnel Seepage Field under Different Waterproof and Drainage System Using Analytical Methods 被引量:5
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作者 Serges Mendomo Meye Zhenzhong Shen 《Engineering(科研)》 2020年第6期401-423,共23页
Tunnel seepage is an important factor affecting the progress and safety of tunnel construction. In this paper, the mining method tunnel construction in the water-rich weathered granite stratum is taken as the research... Tunnel seepage is an important factor affecting the progress and safety of tunnel construction. In this paper, the mining method tunnel construction in the water-rich weathered granite stratum is taken as the research object. Through the analytical calculation method, the distribution law of tunnel seepage field under different waterproof and drainage types is studied, and the comparative analysis is carried out. According to the analytical solution, the influencing factors of grouting parameters are proposed. The sensitivity of the tunnel seepage field to the variation of grouting parameters is analyzed. A novel waterproof and drainage system, and construction technology suitable for subway tunnels with large buried depth below groundwater level were proposed. 展开更多
关键词 Seepage Field WATERPROOF analytical Solutions TUNNEL controlled Drainage
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Penetration analytical model of three dimensional welding temperature field and experiment rectification
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作者 李亮玉 付瑞东 《China Welding》 EI CAS 2000年第2期81-86,共6页
A three dimensional analytical model for heat conduction in a plate of finite size with a Gaussian distributed moving heat source, is obtained using the Heat Cumulating Principle and the Method of Image in arc we... A three dimensional analytical model for heat conduction in a plate of finite size with a Gaussian distributed moving heat source, is obtained using the Heat Cumulating Principle and the Method of Image in arc welding, and an estimated method of back width of seam is introduced by making use of the model and the measured top face information of temperature field . To prove the validity of the model, a series of GTA bead on plate welding were performed on a medium carbon steel under various welding conditions, the experimental results show that the theoretical prediction can provide acceptable accuracy, so the next penetration control will be based on the model. 展开更多
关键词 penetration control analytical model temperature fi
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A Numerical-analytic Method for Quickly Predicting Springback of Numerical Control Bending of Thin-walled Tube 被引量:3
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作者 Mei ZHAN He YANG Liang HUANG 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2006年第5期713-720,共8页
Springback is one of important factors influencing the forming quality of numerical control (NC) bending of thin-walled tube. In this paper, a numerical-analytic method for springback angle prediction of the process... Springback is one of important factors influencing the forming quality of numerical control (NC) bending of thin-walled tube. In this paper, a numerical-analytic method for springback angle prediction of the process was put forward. The method is based on springback angle model derived using analytic method and simulation results from three-dimensional (3D) rigid-plastic finite element method (FEM). The method is validated through comparison with experimental results. The features of the method are as follows: (1) The method is high in efficiency because it combines advantages of rigid-plastic FEM and analytic method. (2) The method is satisfactory in accuracy, since the field variables used in the model is resulting from 3D rigid-plastic FEM solution, and the effects both of axial force and strain neutral axis shift have been included. (3) Research on multi-factor effects can be carried out using the method due to its advantage inheriting from rigid-plastic FEM. The method described here is also of general significance to other bending processes. 展开更多
关键词 Thin-walled tube Numerical control bending SPRINGBACK Numerical-analytic method 3D rigid-plastic FEM
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Analytic Solutions to Optimal Control Problems with Constraints
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作者 Dan Wu 《Applied Mathematics》 2015年第14期2326-2339,共14页
In this paper, the analytic solutions to constrained optimal control problems are considered. A novel approach based on canonical duality theory is developed to derive the analytic solution of this problem by reformul... In this paper, the analytic solutions to constrained optimal control problems are considered. A novel approach based on canonical duality theory is developed to derive the analytic solution of this problem by reformulating a constrained optimal control problem into a global optimization problem. A differential flow is presented to deduce some optimality conditions for solving global optimizations, which can be considered as an extension and a supplement of the previous results in canonical duality theory. Some examples are given to illustrate the applicability of our results. 展开更多
关键词 CONSTRAINED Optimal control analytIC Solution CANONICAL DUALITY Theory Global Optimization
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Evaluation of Environmental Sound Pressure Level,Drawing of Noise-Isosonic Map Using Surfer V.19,and Prioritization of Engineering Noise Control Methods Using the Analytic Hierarchy Process(AHP):A Field Study in CGS Stations
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作者 Sajad Zare Abdolrasoul Rahmani +3 位作者 Javad Korouzhdeh Masoud Hajghani Rouhollah Rostami Reza Esmaeili 《Sound & Vibration》 EI 2022年第3期275-291,共17页
Noise pollution is one of the most significant harmful physical factors in the industrial and occupational environments.Due to the high costs of exposure to excessive noise;continuous sound evaluation,propose and impl... Noise pollution is one of the most significant harmful physical factors in the industrial and occupational environments.Due to the high costs of exposure to excessive noise;continuous sound evaluation,propose and implement noise control plans in occupational environments is necessary.Thus,the present study aimed to review environmental sound measurements,drawing of noise maps,and prioritizing the engineering noise control methods using the Analytic Hierarchy Process(AHP).This study was a descriptive-analytical study that aimed to assess occupational noises and present a control plan in the City Gas Stations(CGSs)of Kerman,Iran in 2021.The present study was done in two phases.In the first phase,six CGSs were investigated to measure and evaluate the noise.In addition,the noise map of a CGS was drawn using the Surfer software.Finally,the AHP was used in the second phase of the research to prioritize the control measures.In this phase,four criteria and ten alternatives were identified.According to first phase results,the sound pressure level(SPL)of the stations varied from 76 to 98 dBA.Besides,the majority of the studied stations had a sound level higher than 85 dBA(danger zone).The second phase of the study showed that out of the four evaluated criteria,the executability criterion had the highest impact and the cost criterion had the lowest impact on the selection of control measures with a weight of 0.587 and 0.052,respectively.Based on the results of prioritization of the alternatives,using a silenced regulator(weight of 0.223)and increasing the thickness of the tube(weight of 0.023)had the highest and lowest priorities among the alternatives,respectively.The use of engineering noise control methods such as using silenced regulators was the best way to control the noises of CGSs.Additionally;it is noteworthy that AHP is a practical method for prioritizing alternatives to achieve the most accurate decision-making.The results of AHP can be of great help to health and safety experts and managers in choosing the sound engineering control measures more precisely. 展开更多
关键词 Engineering noise control sound pressure level noise map analytic hierarchy process
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Modeling and Comprehensive Review of Signaling Storms in 3GPP-Based Mobile Broadband Networks:Causes,Solutions,and Countermeasures
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作者 Muhammad Qasim Khan Fazal Malik +1 位作者 Fahad Alturise Noor Rahman 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期123-153,共31页
Control signaling is mandatory for the operation and management of all types of communication networks,including the Third Generation Partnership Project(3GPP)mobile broadband networks.However,they consume important a... Control signaling is mandatory for the operation and management of all types of communication networks,including the Third Generation Partnership Project(3GPP)mobile broadband networks.However,they consume important and scarce network resources such as bandwidth and processing power.There have been several reports of these control signaling turning into signaling storms halting network operations and causing the respective Telecom companies big financial losses.This paper draws its motivation from such real network disaster incidents attributed to signaling storms.In this paper,we present a thorough survey of the causes,of the signaling storm problems in 3GPP-based mobile broadband networks and discuss in detail their possible solutions and countermeasures.We provide relevant analytical models to help quantify the effect of the potential causes and benefits of their corresponding solutions.Another important contribution of this paper is the comparison of the possible causes and solutions/countermeasures,concerning their effect on several important network aspects such as architecture,additional signaling,fidelity,etc.,in the form of a table.This paper presents an update and an extension of our earlier conference publication.To our knowledge,no similar survey study exists on the subject. 展开更多
关键词 Signaling storm problems control signaling load analytical modeling 3GPP networks smart devices diameter signaling mobile broadband data access data traffic mobility management signaling network architecture 5G mobile communication
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Analytical libration control law for electrodynamic tether system with current constraint
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作者 Shidong Xu Ti Chen +1 位作者 Hao Wen Dongping Jin 《Astrodynamics》 EI CSCD 2024年第2期237-246,共10页
This study focuses on stabilizing the libration dynamics of an electrodynamic tether system(EDTS)using generalized torques induced by the Lorentz force.In contrast to existing numerical optimization methods,a novel an... This study focuses on stabilizing the libration dynamics of an electrodynamic tether system(EDTS)using generalized torques induced by the Lorentz force.In contrast to existing numerical optimization methods,a novel analytical feedback control law is developed to stabilize the in-plane and out-of-plane motions of a tether by modulating the electric current only.The saturation constraint on the current is accounted for by adding an auxiliary dynamic system to the EDTS.To enhance the robustness of the proposed controller,multiple perturbations of the orbital dynamics,modeling uncertainties,and external disturbances are approximated using a neural network in which the weighting matrix and approximation error are estimated simultaneously,such that these perturbations are well compensated for during the control design of the EDTS.Furthermore,a dynamically scaled generalized inverse is utilized to address the singular matrix in the control law.The closed-loop system is proven to be ultimately bounded based on Lyapunov stability theory.Finally,numerical simulations are performed to demonstrate the effectiveness of the proposed analytical control law. 展开更多
关键词 electrodynamic tether system(EDTS) libration dynamics analytical control current constraint
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MapReduce Based Parallel Bayesian Network for Manufacturing Quality Control 被引量:4
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作者 Mao-Kuan Zheng Xin-Guo Ming +1 位作者 Xian-Yu Zhang Guo-Ming Li 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第5期1216-1226,共11页
Increasing complexity of industrial products and manufacturing processes have challenged conventional statistics based quality management approaches in the cir- cumstances of dynamic production. A Bayesian network and... Increasing complexity of industrial products and manufacturing processes have challenged conventional statistics based quality management approaches in the cir- cumstances of dynamic production. A Bayesian network and big data analytics integrated approach for manufacturing process quality analysis and control is proposed. Based on Hadoop distributed architecture and MapReduce parallel computing model, big volume and variety quality related data generated during the manufacturing process could be dealt with. Artificial intelligent algorithms, including Bayesian network learning, classification and reasoning, are embedded into the Reduce process. Relying on the ability of the Bayesian network in dealing with dynamic and uncertain problem and the parallel computing power of MapReduce, Bayesian net- work of impact factors on quality are built based on prior probability distribution and modified with posterior probability distribution. A case study on hull segment manufacturing precision management for ship and offshore platform building shows that computing speed accelerates almost directly pro- portionally to the increase of computing nodes. It is also proved that the proposed model is feasible for locating and reasoning of root causes, forecasting of manufacturing outcome, and intelligent decision for precision problem solving. The inte- gration ofbigdata analytics and BN method offers a whole new perspective in manufacturing quality control. 展开更多
关键词 Bayesian network Big data analytics MAPREDUCE Quality control
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Water hammer prediction and control:the Green's function method 被引量:4
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作者 Li-Jun Xuan Feng Mao Jie-Zhi Wu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2012年第2期266-273,共8页
By Green's function method we show that the water hammer (WH) can be analytically predicted for both laminar and turbulent flows (for the latter, with an eddy vis- cosity depending solely on the space coordinates... By Green's function method we show that the water hammer (WH) can be analytically predicted for both laminar and turbulent flows (for the latter, with an eddy vis- cosity depending solely on the space coordinates), and thus its hazardous effect can be rationally controlled and mini- mized. To this end, we generalize a laminar water hammer equation of Wang et al. (J. Hydrodynamics, B2, 51, 1995) to include arbitrary initial condition and variable viscosity, and obtain its solution by Green's function method. The pre- dicted characteristic WH behaviors by the solutions are in excellent agreement with both direct numerical simulation of the original governing equations and, by adjusting the eddy viscosity coefficient, experimentally measured turbulent flow data. Optimal WH control principle is thereby constructed and demonstrated. 展开更多
关键词 Water hammer Two-dimensional analytical theory - Pressure transients Pipe-valve flow control
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Time-varying sliding mode control of missile based on suboptimal method 被引量:4
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作者 LI Zongxing ZHANG Rui 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2021年第3期700-710,共11页
This paper proposes a time-varying sliding mode control method to address nonlinear missile body kinematics based on the suboptimal control theory.The analytical solution of suboptimal time-varying sliding surface and... This paper proposes a time-varying sliding mode control method to address nonlinear missile body kinematics based on the suboptimal control theory.The analytical solution of suboptimal time-varying sliding surface and the corresponding suboptimal control law are obtained by solving the state-dependent Riccati equation analytically.Then,the Lyapunov method is used to analyze the motion trend in sliding surface and the asymptotic stability of the closed-loop system is validated.The suboptimal control law is transformed to the form of pseudo-angle-of-attack feedback.The simulation results indicate that the satisfactory performance can be obtained and the control law can overcome the influence of parameter errors. 展开更多
关键词 suboptimal control Riccati equation analytic solution sliding mode control nonlinear control
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A Novel Features Prioritization Mechanism for Controllers in Software-Defined Networking 被引量:1
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作者 Jehad Ali Byungkyu Lee +2 位作者 Jimyung Oh Jungtae Lee Byeong-hee Roh 《Computers, Materials & Continua》 SCIE EI 2021年第10期267-282,共16页
The controller in software-defined networking(SDN)acts as strategic point of control for the underlying network.Multiple controllers are available,and every single controller retains a number of features such as the O... The controller in software-defined networking(SDN)acts as strategic point of control for the underlying network.Multiple controllers are available,and every single controller retains a number of features such as the OpenFlow version,clustering,modularity,platform,and partnership support,etc.They are regarded as vital when making a selection among a set of controllers.As such,the selection of the controller becomes a multi-criteria decision making(MCDM)problem with several features.Hence,an increase in this number will increase the computational complexity of the controller selection process.Previously,the selection of controllers based on features has been studied by the researchers.However,the prioritization of features has gotten less attention.Moreover,several features increase the computational complexity of the selection process.In this paper,we propose a mathematical modeling for feature prioritization with analytical network process(ANP)bridge model for SDN controllers.The results indicate that a prioritized features model lead to a reduction in the computational complexity of the selection of SDN controller.In addition,our model generates prioritized features for SDN controllers. 展开更多
关键词 Software-defined networking controllers feature-based selection QUALITY-OF-SERVICE analytical network process analytical hierarchy process
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Evaluating Watershed Vulnerability in Bernalillo County, New Mexico Using Expert Testimony, Fuzzy Analytic Hierarchy Process, and GIS 被引量:1
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作者 Tracy Sadler Clinton P. Richardson Phillip Miller 《Journal of Water Resource and Protection》 2019年第7期866-885,共20页
Geographic Information System (GIS) software was used to create a watershed vulnerability model for Bernalillo County, New Mexico. Watershed vulnerability was investigated as a function of soil erosion and infiltratio... Geographic Information System (GIS) software was used to create a watershed vulnerability model for Bernalillo County, New Mexico. Watershed vulnerability was investigated as a function of soil erosion and infiltration criteria: precipitation, land slope, soil erodibility (K-factor), vegetation cover (NDVI), land use, drainage density, saturated hydraulic conductivity, and hydrologic soil group. Respective criteria weights were derived using a Fuzzy Analytic Hierarchy Process (FAHP) supported by expert opinion. A survey of 10 experts, representing New Mexico Institute of Mining and Technology (NMT), the New Mexico Bureau of Geology and Mineral Resources (NMBGMR), and the United States Geologic Survey (USGS), provided model input data for an integrated pair-wise comparison matrix for soil erosion and for infiltration. Individual criteria weights were determined by decomposing the respective fuzzy synthetic extent matrix using the centroid method. GIS layers were then combined based on criteria weights to produce maps of soil erosion potential and infiltration potential. A composite watershed vulnerability map was generated by equal weighting of each input map. Model results were categorized into five vulnerability categories: not vulnerable (N), slightly vulnerable (SV), moderately vulnerable (MV), highly vulnerable (HV), and extremely vulnerable (EV). The resulting FAHP/GIS model was used to generate a watershed vulnerability map of discrete areas in Bernalillo County, which may be vulnerable to stormwater run-off events and soil erosion. Such high volume run-off events can cause erosion damage to property and infrastructure. Alternatively, in areas near urban development, stormwater run-off may contribute non-point-source pollutant contamination of New Mexico’s surface water resources. The most problematic areas in Bernalillo County are present in the Eastern and Northwestern portions. However, less than 1% of the total area lies within the lowest and highest vulnerability categories with the majority centered around moderate vulnerability. The results of the model were compared with a previously published crisp AHP method. Both methods showed similar regional vulnerability trends. This MCDS/GIS approach is intended to provide support to local governments and decision makers in selection of suitable structural or nonstructural stormwater control measures. 展开更多
关键词 STORMWATER control Measures Fuzzy analytic Hierarchy Process (FAHP) MULTI-CRITERIA Decision Support Systems GEOGRAPHIC Information System WATERSHED VULNERABILITY
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Analysis of one dimensional and two dimensional fuzzy controllers
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作者 Ban Xiaojun Gao Xiaozhi +1 位作者 Huang Xianlin Wu Tianbao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第2期362-373,共12页
The analytical structures and the corresponding mathematical properties of the one dimensional and two dimensional fuzzy controllers are first investigated in detail. The nature of these two kinds of fuzzy controllers... The analytical structures and the corresponding mathematical properties of the one dimensional and two dimensional fuzzy controllers are first investigated in detail. The nature of these two kinds of fuzzy controllers is next probed from the perspective of control engineering. For the one dimensional fuzzy controller, it is concluded that this controller is a combination of a saturation element and a nonlinear proportional controller, and the system that employs the one dimensional fuzzy controller is the combination of an open-loop control system and a closedloop control system. For the latter case, it is concluded that it is a hybrid controller, which comprises the saturation part, zero-output part, nonlinear derivative part, nonlinear proportional part, as well as nonlinear proportional-derivative part, and the two dimensional fuzzy controller-based control system is a loop-varying system with varying number of control loops. 展开更多
关键词 one dimensional fuzzy controller two dimensional fuzzy controller analytical structures fuzzy inference control system analysis.
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Lateral Dynamic Analysis and Motion Control of a Jet Trencher in Ocean Currents
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作者 Xiang Li Tao Wang +1 位作者 Min Zhao Tong Ge 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2017年第1期26-31,共6页
In order to control the lateral motion of a jet trencher which is important for stable trenching operation,the oscillation characteristics of the jet trencher are researched. The jet trencher is simplified into a sing... In order to control the lateral motion of a jet trencher which is important for stable trenching operation,the oscillation characteristics of the jet trencher are researched. The jet trencher is simplified into a single degree of freedom model with restoring and damping force. The nonlinear mathematical model of the trencher laterally oscillating in ocean currents is established,and its approximate analytical solution is obtained.Results show that the analytical solution has small differences with numerical solution based on the fourth-order Runge-Kutta method and can effectively describe the underwater oscillation. A double-loop PID controller is designed to control the lateral motion displacement of the trencher to return to the center of the pipeline route which is effective and robust for the propulsion system. 展开更多
关键词 TRENCHER dynamic model analytical solution double-loop control ocean currents
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