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Preliminary Study on the Effect of Different Ecological Cultivation Modes on the Water Stability of Soil Aggregates in Rubber Based Agroforestry Systems
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作者 Shiyun Zhan Fengyue Qin +4 位作者 Dongling Qi Zhixiang Wu Chuan Yang Yingying Zhang Qingmao Fu 《Open Journal of Ecology》 2023年第11期782-793,共12页
Rubber trees (Hevea brasiliensis Müll. Arg.) have been commercially cultivated for a century and a half in Asia, particularly in China, and they constitute a common element of plantation ecosystems in tropical re... Rubber trees (Hevea brasiliensis Müll. Arg.) have been commercially cultivated for a century and a half in Asia, particularly in China, and they constitute a common element of plantation ecosystems in tropical regions. Soil health is fundamental to the sustainable development of rubber plantations. The objective of the study is to explore the influence of different complex ecological cultivation modes on the stability of soil aggregates in rubber based agroforestry systems. In this study, the ecological cultivation mode of rubber—Alpinia oxyphylla plantation, the ecological cultivation mode of rubber—Phrynium hainanense plantations, the ecological cultivation mode of rubber—Homalium ceylanicum plantations and monoculture rubber plantations were selected, and the particle size distribution of soil aggregates and their water stability characteristics were analyzed. The soil depth of 0 - 20 cm and 20 - 40 cm was collected for four cultivation modes. Soil was divided into 6 particle levels > 20 cm. soil was divided into 6 particle levels > 5 mm, 2 - 5 mm, 1 - 2 mm, 0.5 - 1 mm, 0.25 - 0.5 mm, and 0.053 - 0.25 mm according to the wet sieve method. The particle size proportion and water stability of soil aggregates were determined by the wet sieve method. The particle size proportion and water stability of soil aggregates under different ecological cultivation modes were analyzed. The results showed that under different ecological cultivation modes in the shallow soil layer (0 - 20 cm), the rubber—Alpinia oxyphylla plantation and the rubber—Phrynium hainanense plantation promoted the development of dominant soil aggregates towards larger size classes, whereas the situation is the opposite for rubber—Homalium ceylanicum plantation. In soil layer (20 - 40 cm), the ecological cultivation mode of rubber—Phrynium hainanense plantation developed the dominant radial level of soil aggregates to the diameter level of large aggregates. Rubber—Alpinia oxyphylla plantation and rubber—Homalium ceylanicum plantation, three indicators, including the water-stable aggregate content R<sub>0.25</sub> (>0.25 mm water-stable aggregates), mean weight diameter (MWD), and geometric mean diameter (GMD), were all lower than those in the rubber monoculture mode. However, in the rubber—Phrynium hainanense plantation, the water-stable aggregate content R<sub>0.25</sub>, mean weight diameter, and geometric mean diameter were higher than in the rubber monoculture mode, although these differences did not reach statistical significance. 展开更多
关键词 Ecological Complex Cultivation Rubber Plantation Soil Aggregates Soil Aggregate Water Stability Rubber based Agroforestry systems
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Discussion of sources of error in laser-speckle based systems
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作者 Bernhard G.Zogar 《Chinese Optics Letters》 SCIE EI CAS CSCD 2011年第7期41-44,共4页
Applying laser-speckle techniques in material sciences as well as in methods to characterize surface con- ditions of specimen has become the method of choice, especially if a non-contacting principle is sought. This i... Applying laser-speckle techniques in material sciences as well as in methods to characterize surface con- ditions of specimen has become the method of choice, especially if a non-contacting principle is sought. This is almost always the case for specimen that are small in at least one dimension as for example in the materiM testing of foils, fibres, or micromaterials and certainly also if elevated test-temperatures are preventing standard gauges. This letter discusses in some detail sources of error that are quite often over- looked or not even considered as significant at all, but still carry the potential to introduce uncertainties well above the system design specifications. 展开更多
关键词 Discussion of sources of error in laser-speckle based systems
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Evaluation of On-Line MPPT Algorithms for PV-Based Battery Storage Systems
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作者 Belqasem Aljafari Eydhah Almatrafi +3 位作者 Sudhakar Babu Thanikanti Sara A.Ibrahim Mohamed A.Enany Marwa M.Ahmed 《Computers, Materials & Continua》 SCIE EI 2022年第11期3595-3611,共17页
This paper presents a novel Simulink models with an evaluation study of more widely used On-Line Maximum Power Point tracking(MPPT)techniques for Photo-Voltaic based Battery Storage Systems(PV-BSS).To have a full comp... This paper presents a novel Simulink models with an evaluation study of more widely used On-Line Maximum Power Point tracking(MPPT)techniques for Photo-Voltaic based Battery Storage Systems(PV-BSS).To have a full comparative study in terms of the dynamic response,battery state of charge(SOC),and oscillations around the Maximum Power Point(MPP)of the PV-BSS to variations in climate conditions,these techniques are simulated in Matlab/Simulink.The introduced methodologies are classified into two types;the first type is conventional hill-climbing techniques which are based on instantaneous PV data measurements such as Perturb&Observe and Incremental Conductance techniques.The second type is a novel proposed methodology is based on using solar irradiance and cell temperature measurements with pre-build Adaptive Neuro-Fuzzy Inference System(ANFIS)model to predict DC–DC converter optimum duty cycle to track MPP.Then evaluation study is introduced for conventional and proposed On-Line MPPT techniques.This comparative study can be useful in specifying the appropriateness of the MPPT techniques for PV-BSS.Also the introduced model can be used as a valued reference model for future research related to Soft Computing(SC)MPPT techniques.A significant improvement of SOC is achieved by the proposed model and methodology with high accuracy and lower oscillations. 展开更多
关键词 Photo-voltaic based battery storage systems adaptive neuro-fuzzy inference system maximum power point tracking perturb&observe technique incremental conductance technique state of charge
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基于WordCloud技术的MBSE发展态势研究
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作者 董梦如 王国新 +2 位作者 鲁金直 马君达 阎艳 《系统工程与电子技术》 EI CSCD 北大核心 2024年第2期534-548,共15页
基于IEEE及国际系统工程协会(International Council on Systems Engineering,INCOSE)社区会刊,提取与基于模型的系统工程(model based systems engineering,MBSE)领域相关的167篇顶刊的关键词和摘要。采用Python及其第三方库WordCloud... 基于IEEE及国际系统工程协会(International Council on Systems Engineering,INCOSE)社区会刊,提取与基于模型的系统工程(model based systems engineering,MBSE)领域相关的167篇顶刊的关键词和摘要。采用Python及其第三方库WordCloud技术,以可视化形式展示MBSE领域研究内容并对MBSE发展态势进行研究。研究结果表明,MBSE在产品研发全生命周期,应用建模技术来支持系统需求、设计、分析、验证与确认等活动,在系统架构设计方面具有重要作用,将MBSE与安全性分析、可靠性分析方法结合也是MBSE的重要研究内容;系统建模语言(system modeling language,SysML)和对象过程方法(object process method,OPM)分别是目前MBSE研究领域中最受欢迎的建模语言和建模方法;将MBSE方法与本体进行结合是规范MBSE模型表达的重要手段,将MBSE与信息物理系统、数字孪生、并行工程领域进行融合研究是MBSE的重要发展方向。所提研究为使用WordCloud文本分析技术来探索当前的MBSE研究提供了技术路线参考,有助于对MBSE的未来发展态势进行预测。 展开更多
关键词 基于模型的系统工程(model based systems engineering MBSE) MBSE顶刊 WordCloud MBSE发展态势
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Study on the System Design of Multiple Expert Systems Integrated Decision Support System
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作者 Wang, Zongjun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1993年第1期74-81,共8页
There has been an increasing interest in integrating decision support systems (DSS) and expert systems (ES) to provide decision makers a more accessible, productive and domain-independent information and computing env... There has been an increasing interest in integrating decision support systems (DSS) and expert systems (ES) to provide decision makers a more accessible, productive and domain-independent information and computing environment. This paper is aimed at designing a multiple expert systems integrated decision support system (MESIDSS) to enhance decision makers' ability in more complex cases. The basic framework, management system of multiple ESs, and functions of MESIDSS are presented. The applications of MESIDSS in large-scale decision making processes are discussed from the following aspects of problem decomposing, dynamic combination of multiple ESs, link of multiple bases and decision coordinating. Finally, a summary and some ideas for the future are presented. 展开更多
关键词 Computational methods Computer architecture Database systems Expert systems Information management Knowledge based systems Large scale systems Logic design systems analysis User interfaces
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Single-ended Fault Detection Scheme Using Support Vector Machine for Multi-terminal Direct Current Systems Based on Modular Multilevel Converter
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作者 Guangyang Zhou Xiahui Zhang +2 位作者 Minxiao Han Shaahin Filizadeh Zhi Geng 《Journal of Modern Power Systems and Clean Energy》 SCIE EI CSCD 2023年第3期990-1000,共11页
This paper proposes a single-ended fault detection scheme for long transmission lines using support vector machine(SVM)for multi-terminal direct current systems based on modular multilevel converter(MMC-MTDC).The sche... This paper proposes a single-ended fault detection scheme for long transmission lines using support vector machine(SVM)for multi-terminal direct current systems based on modular multilevel converter(MMC-MTDC).The scheme overcomes existing detection difficulties in the protection of long transmission lines resulting from high grounding resistance and attenuation,and also avoids the sophisticated process of threshold value selection.The high-frequency components in the measured voltage extracted by a wavelet transform and the amplitude of the zero-mode set of the positive-sequence voltage are the inputs to a trained SVM.The output of the SVM determines the fault type.A model of a four-terminal DC power grid with overhead transmission lines is built in PSCAD/EMTDC.Simulation results of EMTDC confirm that the proposed scheme achieves 100%accuracy in detecting short-circuit faults with high resistance on long transmission lines.The proposed scheme eliminates mal-operation of DC circuit breakers when faced with power order changes or AC-side faults.Its robustness and time delay are also assessed and shown to have no perceptible effect on the speed and accuracy of the detection scheme,thus ensuring its reliability and stability. 展开更多
关键词 Fault detection short-circuit fault multi-terminal direct current systems based on modular multilevel converter support vector machine(SVM) wavelet transform
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A Survey on the Role of Complex Networks in IoT and Brain Communication
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作者 Vijey Thayananthan Aiiad Albeshri +2 位作者 Hassan A.Alamri Muhammad Bilal Qureshi Muhammad Shuaib Qureshi 《Computers, Materials & Continua》 SCIE EI 2023年第9期2573-2595,共23页
Complex networks on the Internet of Things(IoT)and brain communication are the main focus of this paper.The benefits of complex networks may be applicable in the future research directions of 6G,photonic,IoT,brain,etc... Complex networks on the Internet of Things(IoT)and brain communication are the main focus of this paper.The benefits of complex networks may be applicable in the future research directions of 6G,photonic,IoT,brain,etc.,communication technologies.Heavy data traffic,huge capacity,minimal level of dynamic latency,etc.are some of the future requirements in 5G+and 6G communication systems.In emerging communication,technologies such as 5G+/6G-based photonic sensor communication and complex networks play an important role in improving future requirements of IoT and brain communication.In this paper,the state of the complex system considered as a complex network(the connection between the brain cells,neurons,etc.)needs measurement for analyzing the functions of the neurons during brain communication.Here,we measure the state of the complex system through observability.Using 5G+/6G-based photonic sensor nodes,finding observability influenced by the concept of contraction provides the stability of neurons.When IoT or any sensors fail to measure the state of the connectivity in the 5G+or 6G communication due to external noise and attacks,some information about the sensor nodes during the communication will be lost.Similarly,neurons considered sing the complex networks concept neuron sensors in the brain lose communication and connections.Therefore,affected sensor nodes in a contraction are equivalent to compensate for maintaining stability conditions.In this compensation,loss of observability depends on the contraction size which is a key factor for employing a complex network.To analyze the observability recovery,we can use a contraction detection algorithm with complex network properties.Our survey paper shows that contraction size will allow us to improve the performance of brain communication,stability of neurons,etc.,through the clustering coefficient considered in the contraction detection algorithm.In addition,we discuss the scalability of IoT communication using 5G+/6G-based photonic technology. 展开更多
关键词 Complex networks emerging communication IoT based on 6G systems NEUROSCIENCE photonic technology
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A Hierarchical Framework for Visualising and Simulating Supply Chains in Virtual Environments 被引量:3
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作者 Hai-Yan Zhang Institute of Engineering Mechanics, China Earthquake Administration, 29 Xuefu Road, Harbin 150018, PRC School of Computing, University of Derby, Kedleston Road, Derby DE22 1GB, UK Zheng-Xu Zhao Department of Instrumentation Science and Engineering, Southeast University, Nanjing 210096, PRC School of Mechanical & Manufacturing Engineering, Shandong University, Jinan 250061, PRC School of Computing, University of Derby, Kedleston Road, Derby DE22 1GB, UK 《International Journal of Automation and computing》 EI 2005年第2期144-154,共11页
This paper presents research into applying virtual environment (VE) technology to supply chain management (SCM). Our research work has employed virtual manufacturing environments to represent supply chain nodes to sim... This paper presents research into applying virtual environment (VE) technology to supply chain management (SCM). Our research work has employed virtual manufacturing environments to represent supply chain nodes to simulate processes and activities in supply chain management. This will enable those who are involved in these processes and activities to gain an intuitive understanding of them, so as to design robust supply chains and make correct decisions at the right time. A framework system and its hierarchical structure for visualising and simulating supply chains in virtual environments are reported and detailed in this paper. 展开更多
关键词 Virtual environments supply chains 3D visualising SIMULATING WEB based systems
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IDSS: Designing to Extend the Cognitive Limits 被引量:1
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作者 Feng, Shan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1993年第1期33-44,共12页
The paper presents the conceptual and operational basis of the creation of IDSS based on our recent research experience. In this paper, an intelligent decision support system, IDSS is defined as: any interactive syste... The paper presents the conceptual and operational basis of the creation of IDSS based on our recent research experience. In this paper, an intelligent decision support system, IDSS is defined as: any interactive system that is specially designed to improve the decision making of its user by extending the user's cognitive decision making abilities. As a result, this view of man-machine joint cognitive system stresses the need to use computational technology to aid the user in the decision making process. And the human's role is to achieve total systems's objectives. The paper outlines the designing procedure in successive steps. First, the decision maker's cognitive needs for decision support are identified. Second, the computationally realizable support functions are defined that could be provided by IDSS. Then, the specific techniques that would best fill the decision needs are discussed. And finally, for system implementation the modern computational technology infrastructure is emphasized. 展开更多
关键词 Artificial intelligence Cognitive systems Computational methods Computer architecture Decision theory Information science Information theory Interactive computer systems Knowledge based systems Man machine systems systems engineering
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INTELLIGENT RESOLUTION OF COOPERATIVE CONFLICT
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作者 李林森 于海勋 +1 位作者 罗继勋 佟明安 《Chinese Journal of Aeronautics》 SCIE EI CSCD 2000年第1期24-28,共6页
First, the concept of cooperative conflict is presented, and the characteristic of cooperative air combat is researched. Then, four methods of conflict resolution are designed by way of the first order predicate logic... First, the concept of cooperative conflict is presented, and the characteristic of cooperative air combat is researched. Then, four methods of conflict resolution are designed by way of the first order predicate logic, i.e., link-up, coordination, accommodation and integration, and corresponding examples are given. A 2 vs 2 air combat simulation was carried out; after conflict resolution, the loss ratio is dropped to 0.54 from the original 1.32, so the enhancement of effectiveness is notable. The present research findings are that the wide conflicts discover the essence of multi-fighter cooperation, i.e., to as fully as possible enhance the effectiveness of each fighter to attain global optimization, and that the possibility of conflict resolution shows the application prospect. The proposed method in this paper is a helpful try to the application of the Fifth Generation Computer in the new generation of C3I system. 展开更多
关键词 ALGORITHMS Artificial intelligence Computer simulation Flight dynamics Knowledge based systems Logic programming OPTIMIZATION
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Systems model-guided rice yield improvements based on genes controlling source, sink, and flow 被引量:5
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作者 Pan Li Tiangen Chang +7 位作者 Shuoqi Chang Xiang Ouyang Mingnan Qu Qingfeng Song Langtao Xiao Shitou Xia Qiyun Deng Xin-Guang Zhu 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2018年第12期1154-1180,共27页
A large number of genes related to source, sink,and flow have been identified after decades of research in plant genetics. Unfortunately, these genes have not been effectively utilized in modern crop breeding. This pe... A large number of genes related to source, sink,and flow have been identified after decades of research in plant genetics. Unfortunately, these genes have not been effectively utilized in modern crop breeding. This perspective paper aims to examine the reasons behind such a phenomenon and propose a strategy to resolve this situation. Specifically, we first systematically survey the currently cloned genes related to source, sink, and flow;then we discuss three factors hindering effective application of these identified genes, which include the lack of effective methods to identify limiting or critical steps in a signaling network, the misplacement of emphasis on properties, at the leaf, instead of the whole canopy level,and the non-linear complex interaction between source,sink, and flow. Finally, we propose the development of systems models of source, sink and flow, together with a detailed simulation of interactions between them and their surrounding environments, to guide effective use of the identified elements in modern rice breeding. These systems models will contribute directly to the definition of crop ideotype and also identification of critical features and parameters that limit the yield potential in current cultivars. 展开更多
关键词 systems model-guided rice yield improvements based on genes controlling source
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A novel successive demultiplexing scheme based on optical-CDMA balanced demodulation for FBG sensor systems 被引量:1
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作者 董惠娟 武剑 张广玉 《Chinese Optics Letters》 SCIE EI CAS CSCD 2009年第1期23-25,共3页
In order to increase the multiplexing density of the fiber Bragg gratings (FBGs) for a low cost per-sensor, based on the analysis of the spectrum shadow distortion (SSD), a novel successive demultiplexing scheme f... In order to increase the multiplexing density of the fiber Bragg gratings (FBGs) for a low cost per-sensor, based on the analysis of the spectrum shadow distortion (SSD), a novel successive demultiplexing scheme for FBG sensors has been developed. It is based on the optical cade division multiple access (CDMA) balanced demodulation. A high-density multiplexing-demultiplexing system for FBG sensors has been designed, and corresponding simulation carried out has demonstrated that the FBG sensors' reflective signals can still be obtained accurately and respectively, even if FBG sensors' operating bandwidths heavily overlap. The SSD has been greatly mitigated. 展开更多
关键词 FBG CDMA A novel successive demultiplexing scheme based on optical-CDMA balanced demodulation for FBG sensor systems
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Sensitivity analysis of an HgCdTe based photovoltaic receiver for long-wavelength free space optical communication systems 被引量:1
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作者 A.D.D.Dwivedi P.Chakrabarti 《Optoelectronics Letters》 EI 2009年第1期21-25,共5页
We examine theoretically the performance of an Hg0.77Cd0.23Te based p-n photodetector/HFET optical receiver due to its possible application at 10.6 μm free space optical communication system at high bit rate.A rigoro... We examine theoretically the performance of an Hg0.77Cd0.23Te based p-n photodetector/HFET optical receiver due to its possible application at 10.6 μm free space optical communication system at high bit rate.A rigorous noise model of the receiver has been developed for this purpose.We calculate the total noise and sensitivity of the receiver.The front-end of the receiver exhibits a sensitivity of -45 dBm at a bit rate of 1 Gb/s and -30 dBm at a bit rate of 10 Gb/s,and the total mean-square noise curren t〈i2n〉=5×10-15 A2 at a bit rate of 1 Gb/s an d〈i2n〉 =10-12 A2 at a bit rate of 10 Gb/s,and a 3-dB bandwidth of 10 GHz. 展开更多
关键词 Hg HFET Sensitivity analysis of an HgCdTe based photovoltaic receiver for long-wavelength free space optical communication systems free
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Performance Optimization of Dispersion-Managed WDM Systems Based on Four-Wave Mixing
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作者 Shiming Gao Changxi Yang Guofan JinState Key Laboratory of Precision Measurement Technology and Instruments, Tsinghua University, Beijing 100084, P. R. China, 《光学学报》 EI CAS CSCD 北大核心 2003年第S1期39-40,共2页
We systemically investigate the interchannel four-wave mixing (FWM) in dispersion-managed WDM systems with arbitrary launch position. We optimize the number of fiber sections, and the dispersion ratio for the system p... We systemically investigate the interchannel four-wave mixing (FWM) in dispersion-managed WDM systems with arbitrary launch position. We optimize the number of fiber sections, and the dispersion ratio for the system performance. 展开更多
关键词 WDM as FWM Performance Optimization of Dispersion-Managed WDM systems based on Four-Wave Mixing of Four Wave on
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Novel Scheme for Multiple Channel Pulse Generation from a Single Laser Diodefor 10 Gbit/s Based WDM Systems Using RZ Modulation Format
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作者 H. C. Bao Y. J. Wen H. F. Liu 《光学学报》 EI CAS CSCD 北大核心 2003年第S1期373-374,共2页
A new technique for the generation of multi-channel optical pulse from a single laser diode (LD) is presented in this paper. 35 channel pulse source with 6.5 GHz repetition rate per channel and 32.5 GHz channel spacin... A new technique for the generation of multi-channel optical pulse from a single laser diode (LD) is presented in this paper. 35 channel pulse source with 6.5 GHz repetition rate per channel and 32.5 GHz channel spacing was generated from a subharmonically hybrid mode-locked two section monolithic laser with enhanced amplitude modulation. The obtained pulse source exhibits high extinction ratio (>10 dB) and low level of root mean square (RMS) phase noise (<0.11 rad) over all channels from 1556 nm to 1565... 展开更多
关键词 for in mode WDM Novel Scheme for Multiple Channel Pulse Generation from a Single Laser Diodefor 10 Gbit/s based WDM systems Using RZ Modulation Format from
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Modeling and Solving Material Resources Allocation and Distribution with OR-Based and AI-Guided Method
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作者 CHEN Xueguang LU Ke +1 位作者 FEI Qi Surya B.Yadav 《Systems Science and Systems Engineering》 CSCD 1998年第1期37-45,共9页
ModelingandSolvingMaterialResourcesAlocationandDistributionwithOR┐BasedandAI┐GuidedMethod⒇CHENXueguang*LUKeF... ModelingandSolvingMaterialResourcesAlocationandDistributionwithOR┐BasedandAI┐GuidedMethod⒇CHENXueguang*LUKeFEIQiHuazhongUnive... 展开更多
关键词 artificial intelligence expert systems decision support systems heuristic search Knowledge based systems MODELING multi objective optimization.
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Simplified performance indices and active control force of vibration isolation systems with elastic base
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作者 SUN Hongling 《Chinese Journal of Acoustics》 CSCD 2018年第1期69-88,共20页
Influence of the elasticity of the base on vibration isolation performances of single layer, double layer and floating raft vibration isolation systems is investigated systematically. Characteristics of vibration coup... Influence of the elasticity of the base on vibration isolation performances of single layer, double layer and floating raft vibration isolation systems is investigated systematically. Characteristics of vibration coupling between different vibration isolation systems and different elastic bases are analyzed. Moreover the characteristics of vibration acceleration level difference and force transmissibility of different vibration isolation systems are discussed and their simpli- fled expressions are given. In addition the required control forces of active vibration isolation under different installations of actuators for different vibration isolation systems are compared. The results show that for all vibration isolation systems, the addition of the stiffness and damping of the base can enhance their vibration acceleration level difference and force transmissibility. Moreover for floating raft vibration isolation system, the addition of the stiffness and damping of the raft can enhance its vibration isolation performance and reduce the control force required bv active vibration isolation. 展开更多
关键词 In Simplified performance indices and active control force of vibration isolation systems with elastic base
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