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论我国水源涵养林建设中的几个问题

水土保持学报 1989年第4期3卷 73-82页

作者：王永安林业部中南林业调查规划设计院

我国水源涵养林的现状,一是面积不足,体系不完整,控制和理水功能不强;二是位置不当,作用不明显;三是被人为破坏,乱砍滥伐,中断了涵养水源的功能。建设水源涵养林要从实际出发,因地制宜,坚持科学性、实用性和永久性,组成树种要长龄、繁... 详细信息

我国水源涵养林的现状,一是面积不足,体系不完整,控制和理水功能不强;二是位置不当,作用不明显;三是被人为破坏,乱砍滥伐,中断了涵养水源的功能。建设水源涵养林要从实际出发,因地制宜,坚持科学性、实用性和永久性,组成树种要长龄、繁茂、不早衰和不自枯。它既需要符合本林种目标的经营体系,更需要预见到保证将来的技术政策。对于水源涵养林,为了国土的长治久安,在任何情况下也不能皆伐,只准对林分中的濒死树和病虫害树等进行择伐;对丧失功能的过熟林木,也只准单株择伐或团状择伐。为了保持水土,稳定大江大河的水量,全国区划为东北三大水系、西北三个山区、燕太山区、长江中上游、珠江上中游、黄河流域和其它水系的水源涵养林体系。

关键词：中国水源涵养林建设

Design and Simulation Research for the Automatic Mixture System of Magnesia Refractory Bricks

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Design and Simulation Research for the Automatic Mixture Sys...

2011 Chinese control and Decision Conference（CCDC）

作者： Yan Wang1,2,Yucheng Zhou3,Weilun Zhao1,2 and Yuanwei Jing21.Shenyang institute of Engineering,Shenyang 110136,china2.College of Information science and Engineering,Northeastern University,Shenyang 110004,china 3.Research institute of Wood Industry,Chinese Academy of forestry,Beijing,100091,china

This paper introduces control requirements,control method choosing,hardware design and software for the automatic mixture system of magnesia refractory bricks.S7-200 series of PLC are used to realize automatic control for batching *** of complexity of automatic mixture system,conventional compensating control method can not meet the required question precisely.A kind of mixture control system,based on dynamic neural network,is designed through analyzing the influence precision factors of *** is studied by collecting the mixture historical data from field *** the simulation results illustrate that the method can reduce the mixture error effectively.

关键词： Automatic mixture system Magnesia refractory bricks Neural network BP algorithm

Analysis on the Fluctuation Behavior of Input Traffic Source on a Network Evolvement Model

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Analysis on the Fluctuation Behavior of Input Traffic Source...

2010 Chinese control and Decision Conference

作者： Lei Ting~1,Yu Zhen-wei~2 1.College of science,Beijing forestry University,Beijing 100083,china 2.School of Mechanical Electronic,china University of Mining & Technology(Beijing),Beijing 100083,china

The fluctuation of input traffic source has a profound influence on the network system,the effective quantitative characterization on the fluctuation behavior is yet in need of *** the network evolvement model,which is based on the evolvement rules,the paper provides an analytical result for description on fluctuation behavior of input traffic ***,the characteristic parameter of fluctuation is defined,based on evolvement rules of network,the probability distribution of input traffic for single node and global network system are subsequently deduced,combined with definition of fluctuation,the mathematical fluctuation expressions of input traffic source is *** results indicate that the total number of host nodes,as well as the rate the duration of generation packets at the host nodes,has enhanced effect on the fluctuation behavior of input traffic source.

关键词： Network Evolvement Model Input Traffic Fluctuation Behavior Quantitative Analysis

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基于PSO的模糊控制及在孵化中的应用

系统仿真学报 2008年第24期20卷 6668-6672页

作者：周国雄晏密英中南林业科技大学电子与信息工程学院长沙410004 中南大学信息科学与工程学院长沙410083

针对孵化系统复杂的动态非线性特性,提出一种基于粒子群优化的模糊控制算法,该算法针对模糊控制器量化因子参数调节的困难,采用PSO的惯性系数的自适应调整机制,用以加速优化算法的收敛性和维持群体的多样性,以寻优模糊控制器量化因子参... 详细信息

针对孵化系统复杂的动态非线性特性,提出一种基于粒子群优化的模糊控制算法,该算法针对模糊控制器量化因子参数调节的困难,采用PSO的惯性系数的自适应调整机制,用以加速优化算法的收敛性和维持群体的多样性,以寻优模糊控制器量化因子参数,将该方法应用于孵化过程,较好的实现了温度、湿度和含氧量的稳定控制。仿真和实际运行结果表明了所提出的算法的有效性和优越性。

关键词：孵化模糊控制粒子群优化(PSO) 量化因子

Construction and analysis of SSH cDNA library of different pathogenicity strains of Bursaphelenchus xylophilus

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Construction and analysis of SSH cDNA library of different p...

第三届全国生物入侵大会

作者： Xu-ling Xu,Xiao-qin Wu~*,Jian-ren Ye,Lin Huang Nanjing forestry University,The key Laboratory of the pest prevention and control of Jiangsu Province, Nanjing 210037,china

Bursaphelenchus xylophilus as the pathogen of pine wilt disease,has caused destructive damage to pine plantations and resulted in the annual loss of millions of pine trees in *** of B. xylophilus is an important factor in the *** has been reported that the pathogenicity of B. xylophilus isolated from different geographical origins has significant *** present,the molecular mechanism of pathogenicity differentiation is still *** order to screen the

关键词： Bursaphelenchus xylophilus Cdna Pathogenicity SSH

Policies, Actions and Effects for china's forestry Response to Global Climate Change

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Chinese forestry science and Technology 2008年第4期7卷 1-7页

作者： LI Zhiyong1 LI Nuyun2 HE Youjun1 WU Shuirong1 1. Research institute of forestry Policy and Information, Chinese Academy of forestry, Beijing 100091, P. R. china 2. Office of Response to Climate Change, Energy Conservation and Emission Reduction, State forestry Administration, Beijing 100714, P. R. china

Climate change is a great concern of various countries, the public and science community, and forest plays an important role in mitigating climate change. The paper made a comprehensive analysis regarding the policy selections of china to promote forestry response to the global climate change, and elaborated the concrete actions and achievements in this regard. Policy selections include: 1) Reinforce tree planting and afforestation, increase the forested area and enhance the capacity of carbon sequestration; 2) Improve forest management and the quality of existing stands, and improve the carbon sequestration services provided by forest ecosystem; 3) Strengthen the soil protection on wetland and forestland, and exert the potentials of carbon sequestration; 4) Boost the nature protection, and conserve the biodiversity; 5) Vigorously exploit forestry bio-energy, and reduce the GHG emission; 6) Enhance the prevention and control of forest fires, diseases and pests as well as of illegal expropriation of forest land, and effectively control the GHG emission; 7) Appropriately increase the use of timber, further improve the utilization rate of timber, extend the use life-span of timber and strengthen the carbon-storing function of timber products; 8) Actively implement forestry programs for carbon sequestration and widen the financing channels for forestry development and carbon sequestration. Meanwhile, with the concrete actions in forestry response to climate change, e.g. setting up a specialized agency responsible for the response to climate change, establishing Asian-Pacific Network for Sustainable Forest Management and Rehabilitation, launching the national evaluation of preferential development areas for forestry CDM (Clean Development Mechanism) projects, initiating the pilot projects for Afforestation and Reforestation Project under the CDM, and creating and operating china Green Carbon Fund, china has made great achievements in her response to climate change. There

关键词： forestry climate change policy selection action effects china

长期氮磷化肥配施对不同种植体系土壤水分的影响

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水土保持研究 2011年第6期18卷 67-70页

作者：危锋郝明德西南林业大学环境科学与工程学院水土保持与荒漠化防治重点学科昆明650224 西北农林科技大学水土保持研究所陕西杨凌712100

利用长期定位实验,在黄土高原旱地研究了22a氮磷化肥配施下不同种植体系土壤水分的变化状况,为合理利用水肥资源提供参考。在小麦连作、豌豆-小麦(2a)+糜子轮作、红豆草-小麦(2a)轮作、豌豆-小麦(2a)+玉米轮作、玉米-小麦(2a)+糜子轮作... 详细信息

利用长期定位实验,在黄土高原旱地研究了22a氮磷化肥配施下不同种植体系土壤水分的变化状况,为合理利用水肥资源提供参考。在小麦连作、豌豆-小麦(2a)+糜子轮作、红豆草-小麦(2a)轮作、豌豆-小麦(2a)+玉米轮作、玉米-小麦(2a)+糜子轮作、小麦(2a)+糜子-玉米轮作6个不同种植体系中,测定土壤剖面(0-300cm)含水量、储水量。结果表明:不同种植体系土壤含水量在土壤剖面上的分布不同,所有处理在土壤剖面140-300cm土层含水量均低于0-140cm土层含水量。不同种植体系在土壤剖面不同土层的储水量不同,在0-300cm土壤储水量各处理表现为豌豆-小麦(2a)+玉米轮作(644.8mm)>小麦(2a)+糜子-玉米轮作(599.6mm)>豌豆-小麦(2a)+糜子轮作(582.3mm)>红豆草-小麦(2a)轮作(574.0mm)>玉米-小麦(2a)+糜子轮作(550.8mm)>小麦连作(536.9mm)。轮作体系0-300cm土壤储水量均高于小麦连作。粮豆轮作土壤储水量高于小麦连作,是黄土高原地区较好的种植方式。

关键词：黄土高原长期试验氮磷化肥不同种植体系土壤水分

Studies on Diagnostic Model of Breast Cancer Based on Saliva Proteome and Bioinformatic

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Studies on Diagnostic Model of Breast Cancer Based on Saliva...

2010 International Conference on Future Information Technology and Computing (FITC 2010)

作者： Cao Meiqun1,2,Wu Weikang2,Gui Zifan3,Sun Kehuan1,Wu Zhengzhi1,4 1.Shenzhen institute of Integrated Traditional Chinese and Western Medicine,Shenzhen Second People’s Hospital,Shenzhen,china 2.Zhongshan School of Medicine,Sun Yat-Sen University,Guangzhou,china 3.College of science and technology,Central South University of forestry and Technology,Changsha,china 4.Shenzhen institute of geriatric medicine Shenzhen,china.

Aim:This study was designed to construct a salivary protein fingerprint model used for early diagnosis of breast cancer by detecting salivary proteins of breast cancer patients and screening specific protein ***:Surface-enhanced laser desorption ionization time-of-flight mass spectrometry（SELDI-TOF-MS） technique was applied to determine the protein mass spectrums of 91 cases of saliva samples（among which 47 cases were breast cancer patients and 44 cases were healthy subjects） to establish a diagnosis model of breast ***:311 protein peaks were detected in the samples of breast cancer patients and healthy control,and 32 protein peaks had statistical significance difference between the two groups.A template consisting of 4 proteins with molecular weights of 4849.31,5224.96,3439.02 and 3559.89 Da respectively was *** could be correctly grouped to breast cancer patients and healthy *** 47 cases of breast cancer,37 cases were correctly diagnosed;34 cases of healthy subjects were correctly *** sensitivity was 78.7%（37/47）;the specificity was 77.2%（34/44）.Conclusions:the salivary protein fingerprint model of breast cancer constructed by SELDI-TOF-MS technique provided a new method with strong specificity and high sensitivity for early screening and diagnosis of breast cancer;and it was worth further research and application.

关键词： SELDI-TOF-MS Diagnosis Model Bioinformatics Breast Cancer Proteome Salivia

Researches on the Mixture Compensating Method Based on Dynamic Neural Network and Genetic Algorithm

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Researches on the Mixture Compensating Method Based on Dynam...

2011 Chinese control and Decision Conference（CCDC）

作者： Weilun Zhao1,2,Yan Wang1,2,Yucheng Zhou3 and Yuanwei Jing21.Shenyang institute of Engineering,Shenyang 110136,china2.College of Information science and Engineering,Northeastern University,Shenyang 110004,china 3.Research institute of Wood Industry,Chinese Academy of forestry,Beijing,100091,china

Because of complexity of automatic mixture system,conventional compensating control method cannot meet the required question precisely.A kind of mixture control system,based on dynamic neural network,is designed through analyzing the influence precision factors of *** is studied by collecting the mixture historical data from field *** the simulation results illustrate that the method can reduce the mixture error effectively.

关键词： Mixture control PLC Dynamic neural network Genetic algorithm