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modelling Land Use/Land Cover Change of River Rwizi Catchment, South-Western Uganda Using GIS and markov Chain model

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Journal of Water Resource and Protection 2024年第2期16卷 181-206页

作者： Lauben Muhangane Morgan Andama Faculty of Agriculture Uganda Martyrs University Nkozi Uganda Faculty of Science Muni University Arua Uganda

Analysis of catchment Land use/Land cover (LULC) change is a vital tool in ensuring sustainable catchment management. The study analyzed land use/land cover changes in the Rwizi catchment, south western Uganda from 1989-2019 and projected the trend by 2040. Landsat images, field observations, key informant interviews and focus group discussions were used to collect data. Changes in cropland, forestland, built up area, grazing land, wetland and open water bodies were analyzed in ArcGIS version 10.2.2 and ERDAS IMAGINE 14 software and a markov chain model. All the LULC classes increased in area except grazing land. Forest land and builtup area between 2009-2019 increased by 370.03% and 229.53% respectively. Projections revealed an increase in forest land and builtup area by 2030 and only built up area by 2040. LULCC in the catchment results from population pressure, reduced soil fertility and high value of agricultural products.

关键词： Land Cover River Catchment Geographic Information System markov model Sustainable Land Management

An Improved markov model for IEEE 802.15.4 Slotted CSMA/CA Mechanism

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Journal of Computer Science & Technology 2009年第3期24卷 495-504页

作者：文浩林闯陈治佳尹浩何滔 Eryk Dutkiewicz Department of Computer Science Tsinghua University Department of Physics and Engineering Macquarie UniversitySydneyAustralia

IEEE 802.15.4 protocol is proposed to meet the low latency and energy consumption needs in low-rate wireless applications, however, few analytical models are tractable enough for comprehensive evaluation of the protocol. To evaluate the IEEE 802.15.4 slotted CSMA/CA channel access mechanism in this paper, we propose a practical and accurate discrete markov chain model, which can dynamically represent different network loads. By computing the steady-state distribution probability of the markov chain, we obtain an evaluation formula for throughput, energy consumption, and access latency. Then we further analyze the parameters that influence performance including packet arrival rate, initial backoff exponent and maximum backoff number. Finally, NS2 simulator has been used to evaluate the performance of the 802.15.4 CSMA/CA mechanism under different scenarios and to validate the accuracy of the proposed model.

关键词： IEEE 802.15.4 markov model CSMA/CA mechanism

A markov model for Subway Composite Energy Prediction

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Computer Systems Science & Engineering 2021年第11期39卷 237-250页

作者： Xiaokan Wang Qiong Wang Liang Shuang Chao Chen Henan Mechanical and Electrical Vocational College Xinzheng451191China School of Electronic and Information Engineering Beijing Jiaotong UniversityBeijing100044China University of Florence Firenze50041Italy

Electric vehicles such as trains must match their electric power supply and demand,such as by using a composite energy storage system composed of lithium batteries and *** this paper,a predictive control strategy based on a markov model is proposed for a composite energy storage system in an urban rail *** model predicts the state of the train and a dynamic programming algorithm is employed to solve the optimization problem in a forecast time ***-time online control of power allocation in the composite energy storage system can be *** standard train operating conditions for simulation,we found that the proposed control strategy achieves a suitable match between power supply and demand when the train is *** with traditional predictive control systems,energy efficiency 10.5%*** system provides good stability and robustness,satisfactory speed tracking performance and control comfort,and significant suppression of disturbances,making it feasible for practical applications.

关键词： markov model predictive control composite energy storage urban rail train

RS-and-GIS-Supported Forecast of Grassland Degradation in Southwest Songnen Plain by markov model

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Geo-Spatial Information Science 2005年第2期8卷 104-109页

作者： LI Jianping ZHANG Bai GAO FengLI Jianping,Ph.D candidate, Northeast Institute of Geography and Agriculture Ecology,CAS,Changchun 130012 Postgraduate School of the Chinese Academy of Sciences,Beijing 100039,China. Northeast Institute of Geography and Agriculture Ecology CAS Changchun Postgraduate School of the Chinese Academy of Sciences Beijing China

By taking Daan city in Jilin Province as a research object and by using TM image in 1989 and ETM + image in 2001 from American LANDSAT satellite,all kinds of maps and documentation,information of grassland,saline-alkalized land,cropland,water area and forestland is extracted by man-computer interactive interpretation method with ArcView and ArcInfo GIS software, and statistics data is acquired. On the basis of this the changing trend of land use types in the next ten years is forecasted and analyzed with markov model. The results indicate that the problem of grassland degradation in the study area is quite serious.

关键词： remote sensing geographic information system grassland degradation imageinterpretation markov model

Customer Segment Prediction on Retail Transactional Data Using K-Means and markov model

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Intelligent Automation & Soft Computing 2023年第4期36卷 589-600页

作者： A.S.Harish C.Malathy SRM Institute of Science and Technology KattankuluthurChennai603203Tamil NaduIndia

Retailing is a dynamic business domain where commodities and goods are sold in small quantities directly to the *** deals with the end user customers of a supply-chain network and therefore has to accommodate the needs and desires of a large group of customers over varied *** volume and volatility of the business makes it one of the prospectiveﬁelds for analytical study and data *** is also why customer segmentation drives a key role in multiple retail business decisions such as marketing budgeting,customer targeting,customized offers,value proposition *** segmentation could be on various aspects such as demographics,historic behavior or preferences based on the use *** this paper,historic retail transactional data is used to segment the custo-mers using K-Means clustering and the results are utilized to arrive at a transition matrix which is used to predict the cluster movements over the time period using markov model *** helps in calculating the futuristic value a segment or a customer brings to the *** marketing designs and budgeting can be implemented using these *** study is speciﬁcally useful for large scale marketing in domains such as e-commerce,insurance or retailers to segment,proﬁle and measure the customer lifecycle value over a short period of time.

关键词： K-means retail analytics clustering cluster prediction markov chain transition matrix RFM model customer segmentation segment prediction markov model segment proﬁling

A novel approach to equipment health management based on auto-regressive hidden semi-markov model(AR-HSMM)

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Science in China(Series F) 2008年第9期51卷 1291-1304页

作者： DONG Ming School of Mechanical Engineering Shanghai Jiao Tong University Shanghai 200240 China

As a new maintenance method, CBM （condition based maintenance） is becoming more and more important for the health management of complicated and costly equipment. A prerequisite to widespread deployment of CBM technology and prac- tice in industry is effective diagnostics and prognostics. Recently, a pattern recog- nition technique called HMM （hidden markov model） was widely used in many fields. However, due to some unrealistic assumptions, diagnositic results from HMM were not so good, and it was difficult to use HMM directly for prognosis. By relaxing the unrealistic assumptions in HMM, this paper presents a novel approach to equip- ment health management based on auto-regressive hidden semi-markov model （AR-HSMM）. Compared with HMM, AR-HSMM has three advantages： 1） It allows explicitly modeling the time duration of the hidden states and therefore is capable of prognosis. 2） It can relax observations＇ independence assumption by accom- modating a link between consecutive observations. 3） It does not follow the unre- alistic markov chain＇s memoryless assumption and therefore provides more pow- erful modeling and analysis capability for real problems. To facilitate the computa- tion in the proposed AR-HSMM-based diagnostics and prognostics, new forward- backward variables are defined and a modified forward-backward algorithm is de- veloped. The evaluation of the proposed methodology was carried out through a real world application case study： health diagnosis and prognosis of hydraulic pumps in Caterpillar Inc. The testing results show that the proposed new approach based on AR-HSMM is effective and can provide useful support for the decision- making in equipment health management.

关键词： auto-regressive hidden semi-markov model diagnosis prognosis markov model

A new MPPT method for photovoltaic grid-connected system based on markov model

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A new MPPT method for photovoltaic grid-connected system bas...

Land use change of Kitakyushu based on landscape ecology and markov model

第36届中国控制会议

作者： Suwei Zhai Yonghui Sun Jiaqiang Wang Bowen Zhang College of Energy and Electrical Engineering Hohai University

ISBN: (纸本)9781538629185

This paper addresses the problem of maximum power point tracking for photovoltaic grid-connected system based on markov model. Considering the stochastic characteristic of solar irradiation, a new maximum power point tracking method based on markov model is proposed. Four discrete states are defined from a markov chain according to the collected solar irradiation data, then the probability transition matrix is obtained. The maximum power point and the corresponding duty ratio after the solar irradiation changed can be estimated by the probability transition matrix and the previous state, the tracking results will be more accurate by adjusting the estimated duty ratio. Finally, simulation results are provided to illustrate the effectiveness of the proposed algorithm.

关键词： MPPT markov model photovoltaic grid-connected

来源： cnki会议评论

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Journal of Geographical Sciences 2008年第4期18卷 455-468页

作者： GUAN Dongjie GAO Weijun WATARI Kazuyuki FUKAHORI Hidetoshi Department of Environmental Space Design Faculty of Environmental Engineering The University of Kitakyushu Kitakyushu 8080135 Japan Planning Section of Sewer and River Department in Kitakyushu Kitakyushu 8080135 Japan

Based on four phases of TM images acquired in 1990, 1995, 2000 and 2005, this paper took Kitakyushu in Japan as a case study to analyze spatial change of land use landscape and corresponding effects on environmental issues guided by landscape ecology theory in virtue of combining technology of Remote Sensing with GIS. Firstly, land use types were divided into 6 classes （farmland, mountain, forestland, water body, urban land and unused land） according to national classification standard of land use, comprehensible ability of TM image and purpose of this study. Secondly, following the theory of landscape ecology analysis, 11 typical landscape indices were abstracted to evaluate the environmental effects and spatial feature changes of land use. Research results indicated that land use has grown more and more diversified and unbalanced, human activities have disturbed the landscape more seriously. Finally, transfer matrix of markov was applied to forecast change process of land use in the future different periods, and then potential land use changes were also simulated from 2010 to 2050. Results showed that conversion tendency for all types of land use in Kitakyushu into urban construction land were enhanced. The study was anticipated to help local authorities better understand and address a complex land use system, and develop improved land use management strategies that could better balance urban expansion and ecological conservation.

关键词： land use landscape ecology markov model Kitakyushu in Japan

markov model for Packet Scheduling in the Transmission of Streaming Media

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Journal of Beijing Institute of Technology 2003年第4期12卷 446-449页

作者：潘浩宋瀚涛王大震 Department of Computer Science and Engineering

The difficulties in the transmission of streaming media are analyzed, the packet scheduling on the streaming media server is studied. A markov model is proposed under the effect of the complex dependency among the streaming media packets and the parameters of the transmission channel. On the basis of the markov model, a policy is made to queue the streaming media packets in the sending buffer by using the iteration method, which can optimize the playback quality under the lack of the channel bandwidth.

关键词： markov model quality of service retransmission technology layered encoding