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Scenario simulation and landscape pattern dynamic changes of land use in the Poverty Belt around Beijing and Tianjin: A case study of Zhangjiakou city, Hebei Province

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Journal of Geographical Sciences 2016年第3期26卷 272-296页

作者：孙丕苓许月卿喻忠磊刘庆果谢保鹏刘佳 College of Resource and Environmental Sciences China Agricultural University School of Geography Beijing Normal University Qianjiang Xinhua Middle School

Land use/cover change has been recognized as a key component in global change and has attracted increasing attention in recent decades. Scenario simulation of land use change is an important issue in the study of land use/cover change, and plays a key role in land use prediction and policy decision. Based on the remote sensing data of Landsat TM images in 1989, 2000 and 2010, scenario simulation and landscape pattern analysis of land use change driven by socio-economic development and ecological protection policies were reported in Zhangjiakou city, a representative area of the Poverty Belt around Beijing and Tianjin. Using a CLUE-S model, along with socio-economic and geographic data, the land use simulation of four scenarios-namely, land use planning scenario, natural development sce- nario, ecological-oriented scenario and farmland protection scenario-were explored accord- ing to the actual conditions of Zhangjiakou city, and the landscape pattern characteristics under different land use scenarios were analyzed. The results revealed the following：（1） Farmland, grassland, water body and unused land decreased significantly during 1989-2010, with a decrease of 11.09%, 2.82%, 18.20% and 31.27%, respectively, while garden land, forestland and construction land increased over the same period, with an increase of 5.71%, 20.91% and 38.54%, respectively. The change rate and intensity of land use improved in general from 1989 to 2010. The integrated dynamic degree of land use increased from 2.21% during 1989-2000 to 3.96% during 2000-2010. （2） Land use changed significantly throughout 1989-2010. The total area that underwent land use change was 4759.14 km2, accounting for 12.53% of the study area. Land use transformation was characterized by grassland to for- estland, and by farmland to forestland and grassland. （3） Under the land use planning sce- nario, farmland, grassland, water body and unused land shrank significantly, while garden land, forestland and construction l

关键词： land use change markov model CLUE-S model landscape metrics Zhangjiakou city

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A priority-based dynamic load transfer algorithm for cellular/WLAN integrated networks

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Journal of Southeast University(English Edition) 2012年第1期28卷 14-20页

作者：陈赓夏玮玮许波沈连丰东南大学移动通信国家重点实验室南京210096 中国人民解放军理工大学通信工程学院南京210016

For the integration network of a cellular network and a wireless local area network （WLAN）, a priority-based dynamic load transfer （PDLT） algorithm is proposed. The dynamic vertical handoffs by call admission control are jointly determined by the network conditions and the traffic characteristics in combination with the location-condition of mobile terminals. When there is no bandwidth resource available in the cellular network or WLAN, the proposed PDLT algorithm allows an incoming voice call or data call within the overlapping area of the cellular network and the WLAN to be directed to the spare network; meanwhile, by dynamically computing the occupancy of the bandwidth resource, the proposed PDLT algorithm also allows an ongoing voice call or data communication to be transferred to the network with a sufficient bandwidth resource according to the given threshold to balance the number of voice/data calls in the two networks. The analysis results of a two-dimensional markov model and the simulation results show that the PDLT algorithm can effectively enhance the whole integrated network＇ s traffic, reduce the blocking probability of new calls and increase the data throughput, and thus decrease the response time for various services.

关键词： cellular network WLAN dynamic load transfer blocking probability markov model

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Cost-effectiveness analysis of tyrosine kinase inhibitors(erlotinib,gefitinib,afatinib and osimertinib)as first-line therapy for epidermal growth factor receptor-mutated advanced non-small cell lung cancer

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Journal of Chinese Pharmaceutical Sciences 2021年第3期30卷 253-263页

作者： Shaohong Luo Liangliang Dong Yiyuan Li Dan Xu Min Chen Department of Pharmacy First Affiliated Hospital of Fujian Medical UniversityFuzhou 350005China Department of Pharmacy Fujian Provincial Jinshan HospitalFuzhou 350028China Clinical College of Fujian Medical University Provincial Hospital Department of PharmacyFujian Provincial HospitalFuzhou 350001China

Gefitinib,erlotinib,afatinib and osimertinib have been recommended as the first-line treatment for epidermal growth factor receptor(EGFR)-mutated advanced non-small cell lung cancer(NSCLC),whereas no studies have compared the cost-effectiveness of these four tyrosine kinase inhibitors(TKIs)simultaneously in *** the present study,we aimed to estimate the cost-effectiveness of erlotinib,gefitinib,afatinib and osimertinib for untreated EGFR-mutated advanced NSCLC.A markov model was constructed to compare the 10-year impact of four TKIs for patients with treatment-naive EGFR-mutated advanced NSCLC from the perspective of the Chinese medical *** data and utility values were derived from published literature,and costs were obtained from Chinese official *** primary output indicator was the incremental cost-effectiveness ratio(ICER).Sensitivity analyses were performed to test the robustness of the *** found that afatinib was estimated to spend the lowest cost with minimum life-years(LYs),while osimertinib was the most expensive regimen with maximum *** ICER of gefitinib versus afatinib was$732/quality-adjusted life-year(QALY),which was less than the willingness-to-pay(WTP)of$29382/*** with gefitinib,erlotinib yielded a higher cost and a shorter lifetime,hence it was identified as a dominated ***,osimertinib was compared to gefitinib,which produced an ICER of$71330/QALY,exceeding the *** suggested that gefitinib was the most cost-effective regimen as the first-line treatment for EGFR-mutated advanced *** the osimertinib price or increasing the WTP threshold to$68558/QALY might enhance the favorability of the outcome,by which osimertinib might become more ***-way sensitivity analysis manifested that the model was robust.

关键词： Cost-effectiveness analysis markov model Tyrosine kinase inhibitor Non-small cell lung cancer First-line therapy Epidermal growth factor receptor

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Availability Analysis for High Voltage Synchronous Motor

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International Journal of Plant Engineering and Management 2004年第3期9卷 123-130页

作者： DINGJin-hua ErlandOlsson ZHOURong DepartmentofInformationDesignandProductDevelopment MalardalensUniversityBox325Eskilstuna63105Sweden DepartmentofMechanicalEngineering DalianInstituteofLightIndustryDalian116034China

The operating experience data for 34 motors running for approximately 15years in paper plants are collected. According to the data set, the reliability and availabilitycharacteristics of a high-voltage synchronous motor are analyzed based on the markov model. The unitor subsystem main rotor with windings in the motor system is more important for the motor system''savailability, though its failure rate is lower compared to other units. Preventive maintenance isfirst introduced as a state in the markov model for the motor system.

关键词： availability markov model reliability synchronous motor

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Landscape Structure Changes in Liangshui Nature Reserve, Northeast China

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Forestry Studies in China 2003年第4期5卷 31-36页

作者： Niu Jianzhi Gao Jiarong Wang Fengyou College of Soil and Water Conservation Beijing Forestry UniversityBeijing 100083P.R.China Heilongjiang Forestry Department Harbin 150000P.R.China

This paper systematically studied the landscape dynamic changes in Liangshui Natural Reserve (LNR) in Heilongjiang Province, northeast China during three periods (1950s, 1970s and 1990s), by applying landscape space model------markov model. The results indicated that the landscape structure in LNR changed and the types of landscape patches increased. The phenomena of increasing and reducing of landscape types happened at the same time and the matrix— natural Pinus koraiensis decreased year by year. The law of transformation of landscape types matches well with the results concluded from statistical data, survey data, and the developing process inherent succession of the forest. By analyzing landscape dynamic changes, some scientific management measures were put forward in this paper.

关键词： landscape dynamics scale markov model

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Cybersecurity: A Statistical Predictive model for the Expected Path Length

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Journal of Information Security 2016年第3期7卷 112-128页

作者： Pubudu Kalpani Kaluarachchi Chris P. Tsokos Sasith M. Rajasooriya Department of Mathematics and Statistics University Of South Florida Tampa FL USA

The object of this study is to propose a statistical model for predicting the Expected Path Length (expected number of steps the attacker will take, starting from the initial state to compromise the security goal—EPL) in a cyber-attack. The model we developed is based on utilizing vulnerability information along with having host centric attack graph. Utilizing the developed model, one can identify the interaction among the vulnerabilities and individual variables (risk factors) that drive the Expected Path Length. Gaining a better understanding of the relationship between vulnerabilities and their interactions can provide security administrators a better view and an understanding of their security status. In addition, we have also ranked the attributable variables and their contribution in estimating the subject length. Thus, one can utilize the ranking process to take precautions and actions to minimize Expected Path Length.

关键词： Vulnerability Attack Graph markov model Security Evaluation Expected Path Length CVSS

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A markov Approach to Exchange Rate Sentiment Analysis of Major Global Currencies

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Open Journal of Statistics 2016年第6期6卷 1181-1195页

作者： Kuthyar Shesha Madhava Rao Anjana Ramachandran Department of Statistics University of Botswana Gaborone Botswana Department of Mathematics University of Botswana Gaborone Botswana

The paper deals with the analysis of exchange rates sentiments. In the approach suggested here a typical exchange rate sentiment is defined on the basis of certain function of mean and standard error of the logarithm of the ratio of successive daily exchange rates. Based on this surmise, the exchange rate sentiments are classified into various states, whereby states are named according to the perceptions of the market player. A markov model is built to capture the uncertainties in exchange rates sentiments. The approach advocated here will be of interest to researchers, exchange rate traders and financial analysts. As an application of the proposed line of approach, we analyse weekly and monthly exchange rate sentiments that govern exchange rates of the major global currencies—EUR, GBP, SDR, YEN, ZAR, USD, using data from 2001-2012. Some interesting conclusions are revealed based on the data analysis approach advocated in this paper.

关键词： Ergodicity Exchange Rates Sentiments markov model Transition Probability Weekly and Monthly States

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Reliability Analysis Method of a Control System for Subsea All-Electric Christmas Tree

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Journal of Marine Science and Application 2021年第2期20卷 354-370页

作者： Peng Liu Qianqian Chen Chao Zheng Guofa Sun School of Mechanical and Automotive Engineering Qingdao University of TechnologyQingdao 266520China Faculty of Engineering and Physical Sciences University of SurreyGuildford GU27XHUK

The subsea all-electric Christmas tree(XT) is a key equipment in subsea production *** it fails,the marine environment will be seriously ***,strict reliability analysis and measures to improve reliability must be performed before a subsea all-electric XT is launched;such measures are crucial to subsea safe production.A fault-tolerant control system was developed in this paper to improve the reliability of XT.A dual-factor degradation model for electrical control system components was proposed to improve the evaluation accuracy,and the reliability of the control system was analyzed based on the markov *** influences of the common cause failure and the failure rate in key components on the reliability and availability of the control system were *** impacts of mean time to repair and incomplete repair strategy on the availability of the control system were also *** results show the key factors that affect system reliability,and a specific method to improve the reliability and availability of the control system was *** reliability analysis method for the control system could be applied to general all-electric subsea control systems to guide their safe production.

关键词： Subsea all-electric Christmas tree Control system Reliability analysis Safe production Dual-factor degradation model markov model

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Study on Land Use Change in Urumqi Based on Remote Sensing Image

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Meteorological and Environmental Research 2013年第11期4卷 47-51页

作者： Lina Fu Liyu Guo College of Geomatics Xi'an University of Science and Technology

[ Objective] The research aimed to study land use change in Urumqi based on remote sensing image. [ Method] By using TM remote sensing images of Urumqi in 1989 and 2007, the images at two periods were corrected, contrasted, analyzed and calculated, and geographical fac- tor was extracted. Finally, we got land use change image during 1989 -2007. [ Result] Due to anthropogenic and natural factors, farmland and ur- ban land in Urumqi occupied a lot of grass and woodland, the areas of canals and lakes were relatively unchanged, and snow coverage area re- duced. [ Conclusion] When improving the economic efficiency of land use, the reduction of forest and grassland, the increases of saline and desert could not be ignored.

关键词： Land use Remote sensing image markov model Driving force Urumqi China

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Fuzzy Reliability Analysis of Disk Array Systems

Fuzzy Reliability Analysis of Disk Array Systems

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第二十六届中国控制会议

作者： Jiang Minghua1,2,Zhou Jingli2,Hu Ming1 1.College of Computer Science &Technology,Wuhan University of Science &Engineering,Wuhan 430073,P.R.China 2.Key Laboratory of Data Storage System(Huazhong University of Science &Technology),Wuhan 430074,P.R.China

Reliability models for various disk array architectures are *** model is very useful calculating with state space by using transition probability and initial *** practice,sometimes we can not have the exact values of λ,μ,ρbut with some uncertainty about these *** combination fuzzy logic and markov model method is introduce and analyzed besides the traditionally used reliability measures such as disk array system *** reliability method is a technique for analyzing fault tolerant designs under considerable uncertainty,such as is seen in compilations of component failure rates,the presented model provides the estimation of the lower and upper boundary of RAID 5 with a single run of the model.

关键词： Fuzzy logic Reliability Analysis RAID 5 markov model

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