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双星多方模型的形状及其对同步子星轨道要素的摄动影响 被引量:1
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作者 李林森 《云南天文台台刊》 CSCD 1997年第4期9-17,共9页
研究了双星多方模型的形状对同步子星轨道要素的摄动影响。假定两子星在同一轨道面上运动,推出了主星对伴星的轨道要素的摄动量。理论结果表明:双星多方模型对轨道半长轴和偏心率只有周期项摄动,无长期摄动,但对近星点和历元平近点... 研究了双星多方模型的形状对同步子星轨道要素的摄动影响。假定两子星在同一轨道面上运动,推出了主星对伴星的轨道要素的摄动量。理论结果表明:双星多方模型对轨道半长轴和偏心率只有周期项摄动,无长期摄动,但对近星点和历元平近点角除有周期摄动外还有长期摄动效应。文中将理论结果应用于同步双星βPer(大陵五双星)的计算上。 展开更多
关键词 双星多方模型 同步子星 轨道要素 摄动影响 轨道
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绝热模型和多方模型下大气压强与高度的关系 被引量:1
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作者 姚云珍 程俊辉 《扬州教育学院学报》 2000年第3期68-70,共3页
本文从理想气体的状态方程及压强公式出发 。
关键词 压强 高度 温度 绝热模型 多方模型
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太阳多方模型对行星轨道要素变化的长期摄动影响
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作者 李林森 《陕西天文台台刊》 CSCD 1995年第6期20-25,共6页
本文利用天体力学中的摄动理论和天体物理学中的气体星多方模型理论研究了太阳多方模型对行星轨道要素变化的长期摄动影响。文中给出了太阳日多方指数n=3的模型由于自转、扁度和内部密度分布等因素对行星轨道要素变化的长期摄动效应... 本文利用天体力学中的摄动理论和天体物理学中的气体星多方模型理论研究了太阳多方模型对行星轨道要素变化的长期摄动影响。文中给出了太阳日多方指数n=3的模型由于自转、扁度和内部密度分布等因素对行星轨道要素变化的长期摄动效应的理论结果。研究结果表明:行星轨道要素除长轴、偏心率和轨道倾角不受长期摄动外升交点经度、近日点经度以及平近点角均受长期摄动的影响。最后利用理论结果对行星轨道要素的长期投动效应做了数值计算,数值结果在表1中给出。 展开更多
关键词 太阳 多方模型 行星轨道 长期摄动 轨道变化
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基于博弈论的食品可追溯信息传递机制分析 被引量:2
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作者 张丽萍 杨江龙 《物流技术》 北大核心 2014年第1期138-140,共3页
在分析我国食品可追溯信息有效传递机制的现状及实践基础上,提出关于农业合作社、食品公司、政府及农户的两阶段四方博弈模型。首先,食品公司、政府、农户展开有关食品可追溯信息的三方博弈,接下来,食品公司与农业合作社展开博弈,并应... 在分析我国食品可追溯信息有效传递机制的现状及实践基础上,提出关于农业合作社、食品公司、政府及农户的两阶段四方博弈模型。首先,食品公司、政府、农户展开有关食品可追溯信息的三方博弈,接下来,食品公司与农业合作社展开博弈,并应用委托-代理模型予以分析。根据食品可追溯信息对食品公司自身价值的高低和对市场经济以及社会环境影响程度的大小,对食品可追溯信息进行分类,分析不同种类的食品可追溯信息主体的博弈过程,得出各主体的参与决策以及食品可追溯信息传递模式的选择。 展开更多
关键词 食品可追溯 信息传递 多方博弈模型 委托—代理模型
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A Multi-model Approach for Soft Sensor Development Based on Feature Extraction Using Weighted Kernel Fisher Criterion 被引量:7
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作者 吕业 杨慧中 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第2期146-152,共7页
Multi-model approach can significantly improve the prediction performance of soft sensors in the process with multiple operational conditions.However,traditional clustering algorithms may result in overlapping phenome... Multi-model approach can significantly improve the prediction performance of soft sensors in the process with multiple operational conditions.However,traditional clustering algorithms may result in overlapping phenomenon in subclasses,so that edge classes and outliers cannot be effectively dealt with and the modeling result is not satisfactory.In order to solve these problems,a new feature extraction method based on weighted kernel Fisher criterion is presented to improve the clustering accuracy,in which feature mapping is adopted to bring the edge classes and outliers closer to other normal subclasses.Furthermore,the classified data are used to develop a multiple model based on support vector machine.The proposed method is applied to a bisphenol A production process for prediction of the quality index.The simulation results demonstrate its ability in improving the data classification and the prediction performance of the soft sensor. 展开更多
关键词 feature extraction weighted kernel Fisher criterion CLASSIFICATION soft sensor
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Maneuvering target tracking algorithm based on cubature Kalman filter with observation iterated update 被引量:4
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作者 胡振涛 Fu Chunling +1 位作者 Cao Zhiwei Li Congcong 《High Technology Letters》 EI CAS 2015年第1期39-45,共7页
Reasonable selection and optimization of a filter used in model estimation for a multiple model structure is the key to improve tracking accuracy of maneuvering target.Combining with the cubature Kalman filter with it... Reasonable selection and optimization of a filter used in model estimation for a multiple model structure is the key to improve tracking accuracy of maneuvering target.Combining with the cubature Kalman filter with iterated observation update and the interacting multiple model method,a novel interacting multiple model algorithm based on the cubature Kalman filter with observation iterated update is proposed.Firstly,aiming to the structural features of cubature Kalman filter,the cubature Kalman filter with observation iterated update is constructed by the mechanism of iterated observation update.Secondly,the improved cubature Kalman filter is used as the model filter of interacting multiple model,and the stability and reliability of model identification and state estimation are effectively promoted by the optimization of model filtering step.In the simulations,compared with classic improved interacting multiple model algorithms,the theoretical analysis and experimental results show the feasibility and validity of the proposed algorithm. 展开更多
关键词 maneuvering target tracking nonlinear filtering cubature Kalman filter(CKF) interacting multiple model(IMM)
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Method for Underwater Target Tracking Based on an Interacting Multiple Model 被引量:6
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作者 XU Weiming LIU Yanchun YIN Xiaodong 《Geo-Spatial Information Science》 2008年第3期186-190,共5页
According to the requirements of real-time performance and reliability in underwater maneuvering target tracking as well as clarifying motion features of the underwater target, an interacting multiple model algorithm ... According to the requirements of real-time performance and reliability in underwater maneuvering target tracking as well as clarifying motion features of the underwater target, an interacting multiple model algorithm based on fuzzy logic inference (FIMM) is proposed. Maneuvering patterns of the target are represented by model sets, including the constant velocity model (CA), the Singer mode~, and the nearly constant speed horizontal-turn model (HT) in FIMM technology. The simulation results show that compared to conventional IMM, the reliability and real-time performance of underwater target tracking can be improved by FIMM algorithm. 展开更多
关键词 underwater target TRACKING interacting multiple model fuzzy logic inference
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SVM with Quadratic Polynomial Kernel Function Based Nonlinear Model One-step-ahead Predictive Control 被引量:12
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作者 钟伟民 何国龙 +1 位作者 皮道映 孙优贤 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第3期373-379,共7页
A support vector machine (SVM) with quadratic polynomial kernel function based nonlinear model one-step-ahead predictive controller is presented. The SVM based predictive model is established with black-box identifica... A support vector machine (SVM) with quadratic polynomial kernel function based nonlinear model one-step-ahead predictive controller is presented. The SVM based predictive model is established with black-box identification method. By solving a cubic equation in the feature space, an explicit predictive control law is obtained through the predictive control mechanism. The effect of controller is demonstrated on a recognized benchmark problem and on the control of continuous-stirred tank reactor (CSTR). Simulation results show that SVM with quadratic polynomial kernel function based predictive controller can be well applied to nonlinear systems, with good performance in following reference trajectory as well as in disturbance-rejection. 展开更多
关键词 nonlinear model predictive control support vector machine nonlinear system identification kernel function
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NOVEL MULTIMEDIA TRAFFIC MODELING BASED CAC SCHEME FOR CDMA COMMUNICATION SYSTEMS 被引量:2
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作者 Zhang Dandan Fang Xuming Zhu Longjie 《Journal of Electronics(China)》 2007年第1期39-45,共7页
As the radio spectrum is a very scarce resource,the Call Admission Control (CAC) is one of the most important parts in radio resource management. The Code Division Multiple Access (CDMA) based next generation wireless... As the radio spectrum is a very scarce resource,the Call Admission Control (CAC) is one of the most important parts in radio resource management. The Code Division Multiple Access (CDMA) based next generation wireless communications systems will support the transmission of multimedia traffic,such as voice,video and data,thus the CAC,which can support the multimedia traffic and guarantee the Quality of Service (QoS) of different traffic,has gained broad attention. In this paper,a novel multimedia traffic modeling method and a corresponding dynamic QoS based CAC are proposed. The analysis and simulation results show that the proposed CAC scheme can guarantee the QoS to different traffic demand,and improve the system performance significantly. 展开更多
关键词 Call Admission Control (CAC) Traffic modeling Code Division Multiple Access (CDMA) Signal-to-Interference Ratio (SIR) Quality of Service (QoS)
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Digital Model of Human Lower Extremity Musculoskeletal System Based on CT & MRI 被引量:1
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作者 尚鹏 王成焘 王立 《Journal of Donghua University(English Edition)》 EI CAS 2004年第4期102-107,共6页
A new method to reconstruct a comparatively complete muscle model of the human lower limb from CT and MRI data is presented. Topological structure of more than fourteen muscles is built and coordinates of origin and i... A new method to reconstruct a comparatively complete muscle model of the human lower limb from CT and MRI data is presented. Topological structure of more than fourteen muscles is built and coordinates of origin and insertion points are given. Based on this model, straight-line model and centroid-line muscle model are acquired. Muscle force prediction is discussed according to the model reconstructed, and a multi-objective optimization method is put forward for evaluating muscle forces of the human lower extremity. 展开更多
关键词 SKELETON Muscular model muscle force optimization.
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Conventional and Predictive Control Algorithms for Controlling Nonlinear Processes Using Multiple-Model Approach 被引量:1
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作者 Ma'moun Abu-Ayyad Issam Abu-Mahfouz Amit Banerjee 《Journal of Mechanics Engineering and Automation》 2013年第1期22-28,共7页
The objective of this work is to formulate and demonstrate the methodology of multi-models for improving the performance of existing advanced control strategies. Multiple models are used to capture the nonlinear proce... The objective of this work is to formulate and demonstrate the methodology of multi-models for improving the performance of existing advanced control strategies. Multiple models are used to capture the nonlinear process dynamics relating to gain and time constant variations. The multi-model strategy was implemented on several controllers such as Smith-Predictor using PI (Proportional-lntegral) and GPC (Generalized Predictive Control). Computer simulations and experiments were conducted on several nonlinear systems and compared to the original form of these controllers. The enhanced approach was tested on controlling the screw speed of an injection molding machine and temperature of a steel cylinder. 展开更多
关键词 Multi-models Smith-Predictor generalized predictive control.
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Phase Analysis and Identification Method for Multiphase Batch Processes with Partitioning Multi-way Principal Component Analysis (MPCA) Model 被引量:2
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作者 董伟威 姚远 高福荣 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第6期1121-1127,共7页
Multi-way principal component analysis (MPCA) is the most widely utilized multivariate statistical process control method for batch processes. Previous research on MPCA has commonly agreed that it is not a suitable me... Multi-way principal component analysis (MPCA) is the most widely utilized multivariate statistical process control method for batch processes. Previous research on MPCA has commonly agreed that it is not a suitable method for multiphase batch process analysis. In this paper, abundant phase information is revealed by way of partitioning MPCA model, and a new phase identification method based on global dynamic information is proposed. The application to injection molding shows that it is a feasible and effective method for multiphase batch process knowledge understanding, phase division and process monitoring. 展开更多
关键词 batch process multi-way principal component analysis MULTIPHASE process monitoring
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A sludge volume index (SVI) model based on the multivariate local quadratic polynomial regression method 被引量:3
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作者 Honggui Han Xiaolong Wu +1 位作者 Luming Ge Junfei Qiao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第5期1071-1077,共7页
In this study, a multivariate local quadratic polynomial regression(MLQPR) method is proposed to design a model for the sludge volume index(SVI). In MLQPR, a quadratic polynomial regression function is established to ... In this study, a multivariate local quadratic polynomial regression(MLQPR) method is proposed to design a model for the sludge volume index(SVI). In MLQPR, a quadratic polynomial regression function is established to describe the relationship between SVI and the relative variables, and the important terms of the quadratic polynomial regression function are determined by the significant test of the corresponding coefficients. Moreover, a local estimation method is introduced to adjust the weights of the quadratic polynomial regression function to improve the model accuracy. Finally, the proposed method is applied to predict the SVI values in a real wastewater treatment process(WWTP). The experimental results demonstrate that the proposed MLQPR method has faster testing speed and more accurate results than some existing methods. 展开更多
关键词 Sludge volume index Multivariate quadratic polynomial regression Local estimation method Wastewater treatment process
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Modeling and Multi-objective Optimization of Refinery Hydrogen Network 被引量:12
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作者 焦云强 苏宏业 +1 位作者 廖祖维 侯卫锋 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第6期990-998,共9页
The demand of hydrogen in oil refinery is increasing as market forces and environmental legislation, so hydrogen network management is becoming increasingly important in refineries. Most studies focused on single-obje... The demand of hydrogen in oil refinery is increasing as market forces and environmental legislation, so hydrogen network management is becoming increasingly important in refineries. Most studies focused on single-objective optimization problem for the hydrogen network, but few account for the multi-objective optimization problem. This paper presents a novel approach for modeling and multi-objective optimization for hydrogen network in refineries. An improved multi-objective optimization model is proposed based on the concept of superstructure. The optimization includes minimization of operating cost and minimization of investment cost of equipment. The proposed methodology for the multi-objective optimization of hydrogen network takes into account flow rate constraints, pressure constraints, purity constraints, impurity constraints, payback period, etc. The method considers all the feasible connections and subjects this to mixed-integer nonlinear programming (MINLP). A deterministic optimization method is applied to solve this multi-objective optimization problem. Finally, a real case study is intro-duced to illustrate the applicability of the approach. 展开更多
关键词 REFINERY multi-objective optimization hydrogen network mixed integer nonlinear programming
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N-Fold Darboux Transformation and Bidirectional Solitons for Whitham-Broer-Kaup Model in Shallow Water
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作者 王雷 高以天 +3 位作者 盖晓玲 孟得新 吕兴 于鑫 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第3期413-422,共10页
Under investigation in this paper is the Whitham-Broer-Kaup (WBK) system, which describes the dispersive long wave in shallow water. Through a variable transformation, the WBK system is casted into a general Broer-Kau... Under investigation in this paper is the Whitham-Broer-Kaup (WBK) system, which describes the dispersive long wave in shallow water. Through a variable transformation, the WBK system is casted into a general Broer-Kaup system whose Lax pair can be derived by the Ablowitz-Kaup-Newell-Segur technology. With symbolic computation, based on the aforementioned Lax pair, the N-fold Darboux transformation is constructed with a gauge transformation and the multi-soliton solutions are obtained. Finally, the elastic interactions of the two-soliton solutions (including the head-on and overtaking collisions) for the WBK system are graphically studied. Those multi-soliton collisions can beused to illustrate the bidirectional propagation of the waves in shallow water. 展开更多
关键词 Whitham Broer-Kaup system Bidirectional solitons Multi-soliton solutions N-fold Darboux transformation Lax pair
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A two-step rectification algorithm for airborne linear images with POS data
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作者 庹红娅 刘允才 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第6期492-496,共5页
Rectification for airborne linear images is an indispensable preprocessing step. This paper presents in detail a two-step rectification algorithm. The first step is to establish the model of direct georeference positi... Rectification for airborne linear images is an indispensable preprocessing step. This paper presents in detail a two-step rectification algorithm. The first step is to establish the model of direct georeference position using the data provided by the Po- sitioning and Orientation System (POS) and obtain the mathematical relationships between the image points and ground reference points. The second step is to apply polynomial distortion model and Bilinear Interpolation to get the final precise rectified images. In this step, a reference image is required and some ground control points (GCPs) are selected. Experiments showed that the final rectified images are satisfactory, and that our two-step rectification algorithm is very effective. 展开更多
关键词 Airborne linear image POS data Two-step rectification algorithm Direct georeference position Polynomial dis- tortion model
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A novel multi-sensor multiple model particle filter with correlated noises for maneuvering target tracking 被引量:3
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作者 胡振涛 Fu Chunling 《High Technology Letters》 EI CAS 2014年第4期355-362,共8页
Aiming at the effective realization of particle filter for maneuvering target tracking in multi-sensor measurements,a novel multi-sensor multiple model particle filtering algorithm with correlated noises is proposed.C... Aiming at the effective realization of particle filter for maneuvering target tracking in multi-sensor measurements,a novel multi-sensor multiple model particle filtering algorithm with correlated noises is proposed.Combined with the kinetic evolution equation of target state,a multi-sensor multiple model particle filter is firstly constructed,which is also used as the basic framework of a new algorithm.In the new algorithm,in order to weaken the adverse influence from random measurement noises in the measuring process of particle weight,a weight optimization strategy is introduced to improve the reliability and stability of particle weight.In addition,considering the correlated noise existing in the practical engineering,a decoupling method of correlated noise is given by the rearrangement and transformation of the state transition equation and measurement equation.Since the weight optimization strategy and noise decoupling method adopt respectively the center fusion structure and the off-line way,it improves the adverse effect effectively on computational complexity for increasing state dimension and sensor number.Finally,the theoretical analysis and experimental results show the feasibility and efficiency of the proposed algorithm. 展开更多
关键词 multi-sensor information fusion weight optimization correlated noises maneuvering target tracking
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Multi-analysis with mathematic model of 3125 non-thyrogenous masses of the neck
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作者 Yong Li Ming Gao Yun Niu Liying Zhang Yang Yu Yigong Li Xiaolong Li 《The Chinese-German Journal of Clinical Oncology》 CAS 2008年第6期319-325,共7页
Objective: To systematically analyze and summarize non-thyrogenous masses of the neck (NTMN) by consideration of new areas, a large sample size and multiple-aspect analysis. Methods: Our research involved 3125 NTM... Objective: To systematically analyze and summarize non-thyrogenous masses of the neck (NTMN) by consideration of new areas, a large sample size and multiple-aspect analysis. Methods: Our research involved 3125 NTMN cases. We summarized the proportion of various NTMN and the distribution of the neck diseases based on the new international classification. The clinical traits such as sexual proportion and age, etc, were analyzed along with the unknown primary cervical metastatic carcinomas (UPCMC), and built up a mathematical model based on the data above. Results: There were 68 different diseases identified. Among all the NTMN, the percentage of metastatic carcinomas was 63.3%. The neck masses with a focus above the clavicle comprised 62.3% of the metastatic carcinomas whose focuses were clear. Moreover, other results almost supported the "rule of 80%". There was an obvious distribution of traits at every sub level. For example, there were 23 different diseases in level Ⅲ, of which the most common was lymphoma. UPCMC made up 12.3% of all metastatic carcinomas. The clinic cases could be analyzed by our model even to form a primary diagnosis which showed a high coincident rate with clinic diagnosis. Conclusion: NTMN are complex and various, with a definite distribution in each neck level. Data relating component character, sex ratio and UPCMC et al to the clinical traits of NTMN will provide vigorous support for clinical applications. The mathematical model could be an efficient method to synthetically analyze complicate data of NTMN. 展开更多
关键词 NECK non-thyrogenous mass international classification mathematical model
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Research on dynamic characteristics model test scheme for middle pylon of multi-pylon multi-span suspension bridges
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作者 Zhang Yufeng Zhang Dachang 《Engineering Sciences》 EI 2012年第3期64-71,共8页
Multi-pylon multi-span suspension bridge is a new type super flexible structure system, and the rigidity design of middle pylon is one of the main difficult technical issues. Due to the requirements of longitudinal ri... Multi-pylon multi-span suspension bridge is a new type super flexible structure system, and the rigidity design of middle pylon is one of the main difficult technical issues. Due to the requirements of longitudinal rigidity, the structural form and the corresponding foundation type of middle pylon are different from those of the ordinary steel pylon, and the complicated dynamic characteristics make the calculation quite difficult. In this article, exploration has been made in selection of similarity ratio and model materials, section simulation, restriction conditions simulation, fixing of mass blocks, fabrication scheme and testing method by taking into account different construction and working conditions such as restriction conditions and working environment of a three-pylon suspension bridge, to conduct the test experimental design of the dynamic behavior of the middle pylon, with the purpose to reveal its dynamic characteristics and make comparison and analysis with theoretical assumptions, to provide basis for anti-wind and anti-seismic design and reference for the design and research of three-pylon two-span suspension bridges in the future. 展开更多
关键词 multi-pylon multi-span suspension bridge middle pylon dynamic characteristics model test
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Distributed link scheduling method with physical interference model in wireless multi-hop networks
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作者 樊帅 Zhang Lin +1 位作者 Feng Wei Ren Yong 《High Technology Letters》 EI CAS 2013年第4期353-358,共6页
To further increase the throughput of wireless multi-hop networks,a distributed scheduling method is proposed,which takes physical interference model into account.It is assumed that nodes in the network can perform ph... To further increase the throughput of wireless multi-hop networks,a distributed scheduling method is proposed,which takes physical interference model into account.It is assumed that nodes in the network can perform physical carrier sensing,and the carrier sensing range can be set to different values.In the traditional carrier sensing mechanism,the carrier sensing range is computed under the protocol interference model,which is not accurate.Here the optimal carrier sensing range with physical interference model is achieved.Each sending node implements the distributed approach in three phases at each time slot,and all the concurrent transmissions are interference free.Good performance can be achieved under this scheduling approach.The approximation ratio of the distributed method to the optimal one is also proved. 展开更多
关键词 wireless multi-hop network physical interference model distributed scheduling physical carrier sensing
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