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Insights into Elastic and Thermodynamics Properties of Binary Intermetallics in Ni-AI Alloys under Extreme Condition: Full-Electronic Quasi-Harmonic Study
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作者 罗永松 仓玉萍 陈东 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第4期399-406,J0001,共9页
Atomistic modeling based on the accurate first-principles method is used to investigate the lattice parameter, elastic constant, elastic modulus including bulk modulus (B) and shear modulus (G), Poisson's ratio, ... Atomistic modeling based on the accurate first-principles method is used to investigate the lattice parameter, elastic constant, elastic modulus including bulk modulus (B) and shear modulus (G), Poisson's ratio, and elastic anisotropy of Al, NiAl and NiaAl under extreme condition. The elastic constants obtained from calculations meet their mechanical stability criteria. Both NiAl and Ni3Al exhibit ductile behavior due to their high bulk mudulus to shear modulus ratios of B/G ratios. Through the full-electronic quasi-harmonic approximation, in which the mobile electrons are considered, we successfully obtain the thermo-physical properties including the thermal expansion coefficient, bulk modulus, heat capacity and entropy at simultaneously high temperatures and high pressures. The calculated quantities agree well with the available results. Some silent results are also interpreted. Several interesting features in the thermodynamic properties can also be observed. 展开更多
关键词 FIRST-PRINCIPLES Heat capacity Bulk modulus Debye approximation
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Model Recognition of Astronauts Blood Flow Change Under Sustained +Gz Acceleration
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作者 钟秋海 张高明 +1 位作者 王庆林 李宪玉 《Journal of Beijing Institute of Technology》 EI CAS 1999年第3期225-231,共7页
Aim Using animals as object of experiment to acquire various patterns of low cerebral blood pressure and reduced blood capacity in cerebral tissues of astronauts due to the load of acceleration. Methods The isotope ... Aim Using animals as object of experiment to acquire various patterns of low cerebral blood pressure and reduced blood capacity in cerebral tissues of astronauts due to the load of acceleration. Methods The isotope tracking technique was applied to mark the blood and record the dynamic curves of cerebral blood flow changes under various accelerations, and the relevant mathematical model was set up using the method of system recognition. Also the method of factor analyzing was used to select two out of the data collected by eight sensors as two factors. Results One of the two factors reflects the various patterns in the astronaut's upper body, the other for the lower body. Parameters of rise time, delay time and steady value reflect the results under different acceleration. Conclusion Whether for the upper body or the lower body, blood flow changes can be considered as a second order system model. This method provides a new technique and method of doing research on astronaut's endurance of acceleration and selecting astronauts. 展开更多
关键词 ASTRONAUTS system recognition blood volume mathematical model ACCELERATION
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中国最大注塑机研制成功
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《塑料工业》 CAS CSCD 北大核心 2003年第5期53-53,共1页
关键词 注塑机 宁波海天股份有限公司 柱内间距 容模量 锁模力
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Fuzzy Comprehensive Evaluation Model for Water Resources Carrying Capacity in Tarim River Basin,Xinjiang,China 被引量:57
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作者 MENG Lihong CHEN Yaning +1 位作者 LI Weihong ZHAO Ruifeng 《Chinese Geographical Science》 SCIE CSCD 2009年第1期89-95,共7页
This paper explores the method of comprehensive evaluation of water resources carrying capacity and sets up an evaluation model applying the fuzzy comprehensive evaluation method. Based on the data of nature,society,e... This paper explores the method of comprehensive evaluation of water resources carrying capacity and sets up an evaluation model applying the fuzzy comprehensive evaluation method. Based on the data of nature,society,economics and water resources of the Tarim River Basin in 2002,we evaluated the water resources carrying capacity of the basin by means of the model. The results show that the comprehensive grades are 0.438 and 0.454 for Aksu and Kashi prefectures respectively,where the current water resources exploitation and utilization has reached a relative high degree and there is only a very limited water carrying capacity,0.620 for Kizilsu Kirgiz Autonomous Prefecture,where water resources carrying capacity is much higher,and in between for Hotan Prefecture and Bayingolin Mongo-lian Autonomous Prefecture. As a whole,the comprehensive grade of the Tarim River Basin is 0.508 and the current water resources exploitation and utilization has reached a relative high degree. Thus,we suggest that the integrated management of the water resources in the basin should be strengthened in order to utilize water resources scientifically and sustainably. 展开更多
关键词 water resources capacity fuzzy comprehensive evaluation membership degree Tarim River Basin XINJIANG
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Geometry Modeling of Ship Hull Based on Non-uniform B-spline 被引量:4
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作者 王虎 邹早建 《Journal of Shanghai Jiaotong university(Science)》 EI 2008年第2期189-192,共4页
In order to generate the three-dimensional (3-D) hull surface accurately and smoothly,a mixed method which is made up of non-uniform B-spline together with an iterative procedure was developed.By using the iterative m... In order to generate the three-dimensional (3-D) hull surface accurately and smoothly,a mixed method which is made up of non-uniform B-spline together with an iterative procedure was developed.By using the iterative method the data points on each section curve are calculated and the generalized waterlines and transverse section curves are determined.Then using the non-uniform B-spline expression,the control vertex net of the hull is calculated based on the generalized waterlines and section curves.A ship with tunnel stern was taken as test case.The numerical results prove that the proposed approach for geometry modeling of 3-D ship hull surface is accurate and effective. 展开更多
关键词 hull surface geometry modeling non-uniform B-spline iterative procedure
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Urban One-way Traffic Organization and Its Evaluation 被引量:2
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作者 裴玉龙 伊新苗 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2004年第2期121-124,共4页
One-way traffic organization is a direct, efficient and economic method to solve traffic congestion and expand traffie capacity. With its evolution, advantages and disadvantages introduced its setting conditions demon... One-way traffic organization is a direct, efficient and economic method to solve traffic congestion and expand traffie capacity. With its evolution, advantages and disadvantages introduced its setting conditions demonstrated. The general method and processes are summarized in planning for urban one-way streets project, viz. investigation, drawing out and evaluation of project, selecting of project and beneficial analysis. Fuzzy synthetical evaluation other fields is employed to evaluate the project. Its evaluation system and method is introduced and Delphi method is adopted to obtain evaluation index. Finally, taking Harbin city as an example, the application process of above-mentioned method is illuminated. Accordingly, it is proved that the method is exercisable. 展开更多
关键词 one-way traffic organization traffic congestion traffic capacity
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Evaluation model for safety capacity of chemical industrial park based on acceptable regional risk 被引量:6
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作者 陈国华 王树坤 谭小群 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第1期121-127,共7页
The paper defines the Safety Capacity of Chemical Industrial Park(SCCIP) from the perspective of acceptable regional risk. For the purpose of exploring the evaluation model for the SCCIP, a method based on quantitativ... The paper defines the Safety Capacity of Chemical Industrial Park(SCCIP) from the perspective of acceptable regional risk. For the purpose of exploring the evaluation model for the SCCIP, a method based on quantitative risk assessment was adopted for evaluating transport risk and to confirm reasonable safety transport capacity of chemical industrial park, and then by combining with the safety storage capacity, a SCCIP evaluation model was put forward. The SCCIP was decided by the smaller one between the largest safety storage capacity and the maximum safety transport capacity, or else, the regional risk of the park will exceed the acceptable level.The developed method was applied to a chemical industrial park in Guangdong province to obtain the maximum safety transport capacity and the SCCIP. The results can be realized in the regional risk control of the park effectively. 展开更多
关键词 SCCIP Safety transport capacity Safety storage capacity Regional risk
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MIMO Capacity Bounds with Doubly Correlated Rician Channel in Geometrical Channel Model 被引量:2
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作者 Li Yonghua He Zhiqiang Lv Tiejun Lin Jiaru 《China Communications》 SCIE CSCD 2010年第5期9-13,共5页
MIMO system can provide higher capacity in independent conditions. When the spatial-temporal fading correlation exists, the capacity may decrease. In this paper, the geometrical MIMO channel model is presented with Ri... MIMO system can provide higher capacity in independent conditions. When the spatial-temporal fading correlation exists, the capacity may decrease. In this paper, the geometrical MIMO channel model is presented with Rician factor. Based on the MIMO ergodic capacity, the capacity bounds are derived with arbitrary finite number of antennas. The bounds are derived in the exact expressions in doubly correlated MIMO R/clan channel. Then a simple expression for the capacity bounds is attained for the high SNR. Finally, the tightness of derived bounds is verified by Monte Carlo simulation. 展开更多
关键词 MIMO RICIAN capacity BOUNDS
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CC-CV charge protocol based on spherical diffusion model 被引量:1
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作者 李连兴 唐新村 +1 位作者 瞿毅 刘洪涛 《Journal of Central South University》 SCIE EI CAS 2011年第2期319-322,共4页
A new insight into the constant current-constant voltage (CC-CV) charge protocol based on the spherical diffusion model was presented. From the model, the CV-charge process compensates, to a large extent, the capaci... A new insight into the constant current-constant voltage (CC-CV) charge protocol based on the spherical diffusion model was presented. From the model, the CV-charge process compensates, to a large extent, the capacity loss in the CC process, and the capacity loss increases with increasing the charging rate and decreases with increasing the lithium-ion diffusion coefficient and using a smaller r value (smaller particle-size and larger diffusion coefficient) and a lower charge rate will be helpful to decreasing the capacity loss. The results show that the CC and the CV charging processes, in some way, are complementary and the capacity loss during the CC charging process due to the large electrochemical polarization can be effectively compensated from the CV charging process. 展开更多
关键词 lithium-ion battery charge protocol constant current-constant voltage mode capacity loss
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Power allocation and mode selection methods for cooperative communication in the rectangular tunnel 被引量:2
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作者 Zhai Wenyan Sun Yanjing +1 位作者 Xu Zhao Li Song 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2015年第2期253-260,共8页
For the multipath fading on electromagnetic waves of wireless communication in the confined areas,the rectangular tunnel cooperative communication system was established based on the multimode channel model and the ch... For the multipath fading on electromagnetic waves of wireless communication in the confined areas,the rectangular tunnel cooperative communication system was established based on the multimode channel model and the channel capacity formula derivation was obtained.On the optimal criterion of the channel capacity,the power allocation methods of both amplifying and forwarding(AF) and decoding and forwarding(DF) cooperative communication systems were proposed in the limitation of the total power to maximize the channel capacity.The mode selection methods of single input single output(SISO) and single input multiple output(SIMO) models in the rectangular tunnel,through which the higher channel capacity can be obtained,were put forward as well.The theoretical analysis and simulation comparison show that,channel capacity of the wireless communication system in the rectangular tunnel can be effectively enhanced through the cooperative technology;channel capacity of the rectangular tunnel under complicated conditions is maximized through the proposed power allocation methods,and the optimal cooperative mode of the channel capacity can be chosen according to the cooperative mode selection methods given in the paper. 展开更多
关键词 Rectangular tunnel Multimode channel model Channel capacity Cooperative communication Power allocation Mode selection
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Regression model for daily passenger volume of high-speed railway line under capacity constraint 被引量:2
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作者 骆泳吉 刘军 +1 位作者 孙迅 赖晴鹰 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第9期3666-3676,共11页
A non-linear regression model is proposed to forecast the aggregated passenger volume of Beijing-Shanghai high-speed railway(HSR) line in China. Train services and temporal features of passenger volume are studied to ... A non-linear regression model is proposed to forecast the aggregated passenger volume of Beijing-Shanghai high-speed railway(HSR) line in China. Train services and temporal features of passenger volume are studied to have a prior knowledge about this high-speed railway line. Then, based on a theoretical curve that depicts the relationship among passenger demand, transportation capacity and passenger volume, a non-linear regression model is established with consideration of the effect of capacity constraint. Through experiments, it is found that the proposed model can perform better in both forecasting accuracy and stability compared with linear regression models and back-propagation neural networks. In addition to the forecasting ability, with a definite formation, the proposed model can be further used to forecast the effects of train planning policies. 展开更多
关键词 high-speed rail Jinghu high-speed railway(HSR) DEMAND capacity forecasting
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Capacitance sensor for automatic soil retreat measurements
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作者 顾军 杨娟 +4 位作者 尹武良 王超 王化祥 刘泽 程素森 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2008年第4期582-585,共4页
To continuously monitor the soil retreat due to erosion in field,provide valuable information about the erosion processes and overcome the disadvantages of inefficiency,high time-consumption and labor-intensity of exi... To continuously monitor the soil retreat due to erosion in field,provide valuable information about the erosion processes and overcome the disadvantages of inefficiency,high time-consumption and labor-intensity of existing methods,this paper describes a novel capacitance sensor for measuring the soil retreat.A capacitance sensor based probe is proposed,which can measure the depth of the soil around it automatically and the data can be recorded by a data logger.Experimental results in the lab verify its usefulness. 展开更多
关键词 soil erosion capacitance sensor finite element model
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Transmission Capacity Analysis for Linear VANET under Physical Model 被引量:1
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作者 Xinxin He Hang Zhang +2 位作者 Weisen Shi Tao Luo Norman C.Beaulieu 《China Communications》 SCIE CSCD 2017年第3期97-107,共11页
In this study, the transmission capacity of VANETs in a highway scenario is analysed on the basis of a 1D line model and the carrier sense multiple access with collision avoidance(CSMA/CA) protocol. We describe the CS... In this study, the transmission capacity of VANETs in a highway scenario is analysed on the basis of a 1D line model and the carrier sense multiple access with collision avoidance(CSMA/CA) protocol. We describe the CSMA/CA protocol used in IEEE802.11 p from the perspective of the geometric relationship amongst simultaneous transmitters. The desired channel and interfering channels are assumed to experience the same amount of path-loss and Rayleigh fading. On the basis of the proposed model, we analyse the attempted transmission probability of each road segment and the maximum intensity of active transmitters, including their theoretical values. Then, we employ the physical model to obtain the outage probability and derive the upper bound of the transmission capacity of a VANET, which is defined as the average spatial density of successful transmissions in the network. Simulation results indicate that the theoretical value offers a good bound on network capacity. 展开更多
关键词 VANET transmission capacity line model CSMA/CA
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Interference Coordination for Secrecy Enhancement in Random Wireless Networks
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作者 BAI Juan TAO Xiaofeng XU Jin 《China Communications》 SCIE CSCD 2014年第8期28-36,共9页
The co-channel interference modeling is vital for evaluating the secrecy performance in random wireless networks,where the legitimate nodes and eavesdroppers are randomly distributed.In this paper,a new interference m... The co-channel interference modeling is vital for evaluating the secrecy performance in random wireless networks,where the legitimate nodes and eavesdroppers are randomly distributed.In this paper,a new interference model is proposed from the userdominant perspective.The model can provide a better analytical assessment of secrecy performance with interference coordination for the presence of eavesdroppers.The typical legitimate is assumed to be located at the origin,and chooses the closest base station(BS) as its serving BS.The field of interferers is obtained by excluding the desired BSs(including the serving BS and its cooperative BS(s)).In contract with the exiting interference model,it is assumed that desired BSs and interferers belong to the same Poisson Point Process(PPP),and eavesdroppers are distributed according to another independent PPP.Based on this model,the average secrecy transmission capacity is derived in simply analytical forms with interference coordination.Analysis and simulation results show that the secrecy performance can be significantly enhanced by exploiting interference coordination.Furthermore,the average secrecy transmission capacity increases with increasing number of cooperative BSs. 展开更多
关键词 interference coordination poissonpoint process secrecy transmission capacity random wireless networks
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Influence of seismic input on response of Baihetan arch dam 被引量:3
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作者 徐强 陈健云 +1 位作者 李静 赵春风 《Journal of Central South University》 SCIE EI CAS 2014年第6期2437-2443,共7页
The dynamic responses of the arch dam including dam-foundation-storage capacity of water system,using two different earthquake input models,i.e.viscous-spring artificial boundary(AB)condition and massless foundation(M... The dynamic responses of the arch dam including dam-foundation-storage capacity of water system,using two different earthquake input models,i.e.viscous-spring artificial boundary(AB)condition and massless foundation(MF),were studied and analyzed for the 269 m high Baihetan arch dam under construction in China.By using different input models,the stress and opening of contraction joints(OCJs)of arch dam under strong shock were taken into consideration.The results show that the earthquake input models have slight influence on the responses including earthquake stresses and openings of contraction joints in different extents. 展开更多
关键词 seismic input openings of contraction joints massless foundation model viscous-spring artificial boundary condition arch dam
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ON THE CAPACITY REGION OF WIRELESS AD HOC RELAY NETWORKS
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作者 Dai Qinyun Yao Wangsheng +1 位作者 Peng Jianmin Su Gang 《Journal of Electronics(China)》 2006年第6期825-830,共6页
Network capacity is a key characteristic to evaluate the performance of wireless networks, The goal of this paper is to study the capacity of wireless ad hoe relay network. In the model, there is at lnost ns source no... Network capacity is a key characteristic to evaluate the performance of wireless networks, The goal of this paper is to study the capacity of wireless ad hoe relay network. In the model, there is at lnost ns source nodes transmitting signal simultaneously in the network and the arbitrarily complex network coding is allowed. The upper capacity bound of the network model are derived From the max-flow rain-cut theorem and the lower capacity bound are obtained by the rate-distortion function For the Gaussian source. Finally, simulation results show that the upper network capacity will decrease as the number of source nodes is increased. 展开更多
关键词 Capacity region Network capacity Wireless ad hoc relay network Gaussian channel model
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Removal of Pb(Ⅱ) ions from aqueous solutions by litchi pericarp and its leachate
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作者 潘轶敏 姜瑞雪 +2 位作者 杨继利 郑昊 尹儿琴 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第7期1626-1632,共7页
The adsorption capacity of Pb(Ⅱ) on litchi pericarps was investigated as a function of temperature,pH,and adsorbent dose using batch experiments.The experimental data obtained were evaluated using adsorption equilibr... The adsorption capacity of Pb(Ⅱ) on litchi pericarps was investigated as a function of temperature,pH,and adsorbent dose using batch experiments.The experimental data obtained were evaluated using adsorption equilibrium isotherms and a kinetic model.Additionally,the removal of Pb(Ⅱ) in leachate of litchi pericarps was also evaluated.The results show that litchi pericarps exhibit a high adsorption capacity to Pb(Ⅱ),with the maximum removal efficiency occurring at a temperature of 25 ℃,a pH of 6.0-7.0 and an adsorbent dosage of 10 g/L.Langmuir and Freundlich isotherms and the pseudo-second-order kinetic model can all fit the equilibrium adsorption satisfactorily,with correlation coefficients(R^2) of 0.9935,0.9918 and 1.0,respectively.An average removal efficiency of 66.65% is found for Pb(Ⅱ) in leachate of litchi pericarps. 展开更多
关键词 litchi pericarp Pb(ll) ADSORPTION KINETICS isotherms LEACHATE
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Impact of Capacity Parameters on Flexible Inventory Control Decision Model
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作者 WANG Yi LE Meilong 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2020年第S01期124-132,共9页
From the mathematical point of view,the flexible inventory control model is proved in the practical problem application and the rationality of the capacity parameter selection and calculation.The purpose is to activel... From the mathematical point of view,the flexible inventory control model is proved in the practical problem application and the rationality of the capacity parameter selection and calculation.The purpose is to actively respond to demand fluctuations when there is a demand forecast error or a missing part of the demand information,and to avoid the risk of passive variable demand forecasting to set the immutable inventory capacity.At the same time,the game is controlled by the flexible and variable inventory control strategy and the customer’s willingness to demand.The paper mainly studies the influence of the setting of capacity parameters on the booking-limit decision and its benefits under the control of flexible space with variable total capacity.Through the two trends of capacity increase flexibility and capacity reduction flexibility in the flexible inventory control model,the mathematical performance and marginal utility methods are introduced to change the performance of the booking-limit control decision model under different scenarios.The correlation analysis between the capacity limit level and the return under the optimal Bookinglimit decision,and the above two flexibility parameters are obtained. 展开更多
关键词 flexible inventory control capacity parameter booking-limit control decision model revenue management
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A Common Fixed Point Theorem for Compatible Mappings of Type (K) in Intuitionistic Fuzzy Metric space
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作者 K.B. Manandhar K. Jha 《Journal of Mathematics and System Science》 2015年第11期474-479,共6页
The purpose of our paper is to obtain a common fixed point theorem for two pairs of self-mappings of compatible of type (K) in a complete intuitionistic fuzzy Metric space with example. Our result generalized and im... The purpose of our paper is to obtain a common fixed point theorem for two pairs of self-mappings of compatible of type (K) in a complete intuitionistic fuzzy Metric space with example. Our result generalized and improves similar other results in literature. 展开更多
关键词 Compatible mappings Compatible mappings of type (K) and common fixed point.
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OceanRoute: Vessel Mobility Data Processing and Analyzing Model Based on MapReduce
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作者 LIU Chao LIU Yingjian +1 位作者 GUO Zhongwen JING Wei 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第3期594-602,共9页
The network coverage is a big problem in ocean communication, and there is no low-cost solution in the short term. Based on the knowledge of Mobile Delay Tolerant Network(MDTN), the mobility of vessels can create the ... The network coverage is a big problem in ocean communication, and there is no low-cost solution in the short term. Based on the knowledge of Mobile Delay Tolerant Network(MDTN), the mobility of vessels can create the chances of end-to-end communication. The mobility pattern of vessel is one of the key metrics on ocean MDTN network. Because of the high cost, few experiments have focused on research of vessel mobility pattern for the moment. In this paper, we study the traces of more than 4000 fishing and freight vessels. Firstly, to solve the data noise and sparsity problem, we design two algorithms to filter the noise and complement the missing data based on the vessel's turning feature. Secondly, after studying the traces of vessels, we observe that the vessel's traces are confined by invisible boundary. Thirdly, through defining the distance between traces, we design MR-Similarity algorithm to find the mobility pattern of vessels. Finally, we realize our algorithm on cluster and evaluate the performance and accuracy. Our results can provide the guidelines on design of data routing protocols on ocean MDTN. 展开更多
关键词 ocean delay tolerant network MAPREDUCE mobility pattern trace similarity vessel data analysis
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