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生态地境和状态-转换模型的研究综述 被引量:2
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作者 乌兰 韩国栋 +1 位作者 乔江 袁清 《中国草地学报》 CSCD 北大核心 2014年第3期90-97,共8页
阐述了生态地境与状态-转换模型的理论发展及构建方法,并以实例说明其构建过程以及在国内外不同生态系统的应用情况,探讨了生态地境在我国草原管理应用中存在的问题以及对策,以期为草地资源的科学管理与可持续发展提供参考。
关键词 生态地境 状态-转换模型 构建方法 问题及对策
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Single Server Queueing Models and Birth-Death Process
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作者 Moses Okechukwu Onyesolu Doris Chinedu Asogwa 《Computer Technology and Application》 2011年第8期644-649,共6页
A transition diagram is used to describe the behavior of systems. Birth-death equations were derived from transition diagram depicting the state of the birth-death processes. Queue models and characteristics of queue ... A transition diagram is used to describe the behavior of systems. Birth-death equations were derived from transition diagram depicting the state of the birth-death processes. Queue models and characteristics of queue models are also derivable from birth-death processes. These queue models consist of mathematical formulas and relationships that can be used to determine the operating characteristics (performance measures) for a waiting line. Schematic and transition diagrams of different single server queue models were shown. Relationships between birth-death processes, waiting lines (queues) and transition diagrams were given. While M/M/I/K queue model states was limited by K customers and had (K+I) states, M/M/1/1 queue model had only two states. M/G/1/∝/∝ and M/M/1/∝/∝ shared similar characteristics. Many ideal queuing situations employ M/M/1 queueing model. 展开更多
关键词 QUEUE transition diagram MODEL state probability DISTRIBUTION equilibrium.
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基于高分辨率影像的家庭牧场草地利用单元划分 被引量:2
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作者 乌兰 韩国栋 +3 位作者 乔江 袁清 闫瑞瑞 王萨仁娜 《东北师大学报(自然科学版)》 CAS CSCD 北大核心 2014年第4期130-138,共9页
利用高分辨率遥感影像ALOS和实地调查相结合的方法,对内蒙古呼伦贝尔市境内的典型家庭牧场进行了草地利用单元划分和状态-转换模型的构建,在家庭牧场尺度上开展了草地资源合理利用及资源优化的配置研究.结果表明:研究区草地可划分为两... 利用高分辨率遥感影像ALOS和实地调查相结合的方法,对内蒙古呼伦贝尔市境内的典型家庭牧场进行了草地利用单元划分和状态-转换模型的构建,在家庭牧场尺度上开展了草地资源合理利用及资源优化的配置研究.结果表明:研究区草地可划分为两种利用单元,第一种为广泛分布于研究区的高平原-冲积物暗栗钙土-羊草(Leymus chinensis)+贝加尔针茅(Stipa baicalensis)草地单元,占草地面积的98%;第二种为位于5号牧场北部的低地滩地-草甸土-灰脉苔草(Carex appendiculata)+委陵菜(Potentilla chinensis)草地单元,仅占草地面积的2%.第一种草地利用单元的状态-转换模型存在羊草占优势和羊草退化的两个生态状态,依据演替顺序,第一个生态状态包括3个植物群丛,分别为羊草+贝加尔针茅+寸草苔(Carex duriuscula)、羊草+寸草苔、羊草+糙隐子草(Cleistogenes squarrosa)+寸草苔群落,面积占77%;第二个生态状态只有糙隐子草+寸草苔1个群丛,面积占21%.说明该区草地退化状态不是很明显,通过一定的恢复措施可较易转换为羊草占优势的生态状态. 展开更多
关键词 草地利用单元 地形 植被 土壤 ALOS 状态-转换模型
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Research on transformation from UML statechart to interface automata 被引量:1
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作者 李良明 Wang Zhijian Tang Longye 《High Technology Letters》 EI CAS 2010年第2期152-156,共5页
This paper studies the problem of deriving an interface automata model from UML statechart, in which, interface automata is a formaliged model for describing component behavior in an open system, but there is no unive... This paper studies the problem of deriving an interface automata model from UML statechart, in which, interface automata is a formaliged model for describing component behavior in an open system, but there is no universal criterion for deriving behavior from component to construct the model. UML is a widely used modeling standard, yet it is very difficult to apply it to system verification and testing directly for its imprecise semantics. After analyzing the expression ability of the two models, several transforma- tion rules are defined and each step of transformation is described in detail, after that, the approach is illustrated with an example. The paper provides a method for acquiring interface automata and lays the foundation for related research. 展开更多
关键词 model transformation interface automata (IA) UML stateehart
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On Impulse Switching Functions of Inverters as an Orthogonal System
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作者 B. Dobrucky M. Pokomy M. Benova 《Journal of Mathematics and System Science》 2014年第12期743-749,共7页
The paper deals with impulse switching function which are used as exciting functions of one- and multidimensional state-space models of power electronic converters. Obviously, these functions are harmonic but using po... The paper deals with impulse switching function which are used as exciting functions of one- and multidimensional state-space models of power electronic converters. Obviously, these functions are harmonic but using power converters they can be strongly non-harmonic, sometimes piecewise constants with zero spaces between them. Then, one deals with power series of time pulses. The impulse switching functions which are orthogonal ones can be derived from these series. The new impulse switching functions are created using Z-transform, inverse Z-transform and numerical series/sequences. The impulse switching functions created this way can be used for both steady- and transient state investigation of converters. 展开更多
关键词 Power converter impulse switching function Z-TRANSFORM inverse Z-transform modelling and simulation steady stateoperation
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