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地下水-陆生植被系统研究评述

地学前缘 2010年第6期17卷 21-30页

作者：周仰效 UNESCO-IHE Institute for Water Education

依赖于地下水的生态系统广泛分布,潜水含水层本身是个生态系统,地下水不仅维持许多水生生态系统,而且是干旱-半干旱地区陆生植被生存的重要水源。研究地下水与植被的相互联系是生态水文地质学的主要组成部分,重点介绍地下水-植被系统的... 详细信息

依赖于地下水的生态系统广泛分布,潜水含水层本身是个生态系统,地下水不仅维持许多水生生态系统,而且是干旱-半干旱地区陆生植被生存的重要水源。研究地下水与植被的相互联系是生态水文地质学的主要组成部分,重点介绍地下水-植被系统的研究方法。植被吸收的地下水量占总蒸腾量的比例是评价植被依赖地下水程度的一个定量指标,蒸腾量比例呈季节性与区域性变化,取决于植被类型、地下水位埋深与动态变化、土壤岩性与气候条件。植被总蒸腾量可以用涡流相关系统测量。地下水的蒸腾量可以用植物茎流计测量,或者用地下水位昼夜变化估算。用同位素混合模型也能估算地下水占总蒸腾量的比例。植被对地下水位下降的响应可能有两种形式,一种是线性比例响应,另一种是临界突变响应,只有通过长期系统观测植被长势与地下水位的变化才能利用统计分析建立两者响应关系。目前,植被-水文模型只能模拟植被冠层截流与蒸腾对土壤水与地下水的影响,或者模拟土壤水-地下水对植被生长的影响,地下水与植被相互作用与反馈的耦合模型还是个空白。

关键词：地下水生态系统陆生植被地下水依赖程度耦合模型监测系统

Conceptual Model and Stochastic Simulation of Fissure Karstic Groundwater System of Niangziguan

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Conceptual Model and Stochastic Simulation of Fissure Karsti...

Hybrid Estimation of State and Input for Linear Continuous Time-varying Systems:A Game Theory Approach

作者： Zhou yangxiao

Niangziguan Spring,a stable karstic spring,is situated in the limestone region near the Niangziguan,Shanxi Province,with the annual average dis- charge and the standard deviation being 11.7m/s,1.91m/s,respectively. Th...

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自动化学报 2005年第4期31卷 549-554页

作者： yangxiao-Jun WENGZheng-Xin TIANZuo-Hua SHISong-Jiao DepartmentofAutomation ShanghaiJiaotongUniversityShanghai200030

The H∞ hybrid estimation problem for linear continuous time-varying systems is in-vestigated in this paper, where estimated signals are linear combination of state and input. Designobjective requires the worst-case energy gain from disturbance to estimation error be less than a pre-scribed level. Optimal solution of the hybrid estimation problem is the saddle point of a two-playerzero sum di?erential game. Based on the di?erential game approach, necessary and su?cient solvableconditions for the hybrid estimation problem are provided in terms of solutions to a Riccati di?e-rential equation. Moreover, one possible estimator is proposed if the solvable conditions are *** estimator is characterized by a gain matrix and an output mapping matrix that re?ects theinternal relations between the unknown input and output estimation error. Both state and unknowninputs estimation are realized by the proposed estimator. Thus, the results in this paper are alsocapable of dealing with fault diagnosis problems of linear time-varying systems. At last, a numericalexample is provided to illustrate the proposed approach.

关键词：时变系统混合估计竞赛理论 Riccati方程

Organic Acid Concentrations and the Relative Enzymatic Changes During the Development of the Citrus Fruits

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Agricultural Sciences in China 2003年第6期2卷 653-657页

作者： LUOAn-cai yangxiao-hong DENGYing-yi LIChun-fan XIANGKe-shu LIDao-gao BiologicalDepartment ChongqingNormalUniversityChongqing400043P.R.China CollegeofHorticultureandLandscapeArchitecture SouthwestAgriculturalUniversityChongqing400716 FengjieAgriculturalBureau Fengjie404600P.R.China

Seasonal changes in enzyme activities and citrate concentration during the development of citrus fruits were investigated. The result showed that the organic acid concentrations reached a peak in the 100 -130 days after anthesis and gradually declined during later stages of fruit maturation in most varieties of citrus, but declined only slightly thereafter in lemon [Citrus limon(L.)Burm]; there is no relation between the activity of citrate synthetase(CS)and the different acid concentration in different citrus fruits; the increase of the activity of the cytosolic aconitase in the late period of the development of citrus fruits accelerated the degradation of citric acid in citrus fruits; the higher the activity of phosphoenolpyruvate carboxylase(PEPC)and the ratio of NAD-dependent isocitrate hydrogenase(PEPC /NAD-IDH),the more the concentrations of organic acids in citrus fruit.

关键词： Citrus Fruit Organic acid Enzyme activity

The Signal Extraction of Fetal Heart Rate Based on Wavelet Transform and BP Neural Network

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Chinese Journal of Biomedical Engineering(English Edition) 2005年第1期14卷 22-31页

作者： yangxiao-hong ZHANGBang-cheng FUHu-dai ChangchunInstituteofOpticsFineMechanicsandPhysicsChineseAcademyofSciences Changchun130021.China／／AviationUniversityofAirforceChangchun130021China ChangChunUniversityofTechnology Changchun130012China

This paper briefly introduces the collection and recognition of bio-medical sig nals, designs the method to collect FM signals. A detailed discussion on the sys tem hardware, structure and functions is also given. Under LabWindows/CVI,the ha rdware and the driver do compatible, the hardware equipment work properly active ly. The paper adopts multi threading technology for real-time analysis and make s use of latency time of CPU effectively, expedites program reflect speed, impro ve s the program to perform efficiency. One threading is collecting data; the other threading is analyzing data. Using the method, it is broaden to analyze the sig nal in real-time. Wavelet transform to remove the main interference in the FM a nd by adding time-window to recognize with BP network; Finally the results of c ollecting signals and BP networks are discussed.8 pregnant women’s signals of F M were collected successfully by using the sensor. The correct of BP network rec ognition is about 83.3% by using the above measure.

关键词： Fetal heart rate Wavelet transform Signal reco gnition BP neural network

Physiological Characterization of Zn-efficient Rice (Oryza sativa) Genotype at Different Zn^(2+) Levels

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Rice science 2003年第1期10卷 47-51页

作者： CHENGuangcai wangRen-min AlfreadQUAMPAH yangxiao-e CollegeofAgricultureandBiotechnology ZhejiangUniversityHangzhou310029China CollegeofResourceandEnvironment ZhejiangUniversityHangzhou310029China

Physiological characteristics of rice at different Zn^(2+) levels[pZn^(2+)>11.5, 11.3, 11.0, 10.6, 10.3, 9.7] were studied with the Zn-efficient rice cultivars IR34, IR36, IR8192, and Zn-inefficient rice cultivars IR26, Ce 64-7, Biyuzaonuo, which grew in chelator-buffered nutrient solution. There were significant differences in tolerance to zinc deficiency among different rice genotypes. Obvious effects of low zinc activity on the physiological characteristic of rice seedlings were noted. There were significant differences in chlorophyll content, photosynthesis rate, MDA concentration in rice leaf, and H^+ excretion of root. As pZn^(2+) decreased, chlorophyll content and photosynthesis rate decreased at a slower pace in Zn-efficient cultivars compared to Zn-inefficient ones, MDA concentration increased slower while H^+ excretion of root increased faster in Zn-efficient cultivars than those in Zn-inefficient ones. It was suggested that the above indications could be used as indexes to Zn-efficiency of rice.

关键词： rice genotype zinc physiological characteristic nutrient efficiency

Deduction Theorem and Hypothetical Syllogism Rule on Fuzzy Logic System

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Chinese Quarterly Journal of Mathematics 2005年第2期20卷 206-213页

作者： yangxiao-bin DENGShu-xian DepartmentofAppliedMathematics ShanghaiUniversityofFinanceandEconomicsShanghai200433China DepartmentofMathematics HenanTextileCollegeZhengzhou450007China

Cancelled the first axiom L1) or the third axiom L3) of the classical formal logic system we established two kinds of quasi-formal deductive system, LG-R^* and LG^* respectively. In LG-R^* we proved that neither the deduction theorem nor the hypothetical syllogism (HS) rule held but a deduction theorem and an HS rule are obtained in a weak sense. We also proved that both the deduction theorem and the hypothetical syllogism(HS) rule hold in LG^*.

关键词： fuzzy logic system deduction theorem hypothetical syllogism(HS) rule weak HS rule

Uptake, Distribution and Accumulation of Copper in Two Ecotypes of Elsholtzia

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Pedosphere 2003年第4期13卷 359-366页

作者： JIANGLi-Ying yangxiao-E YEZheng-Qian SHIWei-Yong CollegeofEnvironmentalandResourcesSciences ZhejiangUniversityHuajiachiCampusHangzhou310029China CollegeofBiologicalandEnvironmentalEngineering ZhejiangUniversityofTechnologyHangzhou310034China

Two ecotypes of Elsholtzia, Elsholtzia splendens and E. argyi, are dominantplants growing on Cu and Pb-Zn smelters, respectively. Samples of the two ecotypes and thecorresponding soils from fields of a copper mining area and a Pb-Zn mining area ofZhejiang Province,China, were analyzed to investigate Cu or Zn tolerance of these two ecotypes. Effects of nine Culevels (0, 5, 10, 20, 40, 80, 160, 240 and 320 mg Cu L^(-1) as CuSO_4 centre dot 5H_O) on growth anduptake, translocation and accumulation of Cu in these two ecotypes were examined in a solutionculture experiment. The experimental results showed that dry weights (DW) of shoots and roots weredepressed, and growth of E. splendens was less depressed than that of E. argyi when treated with>= 5mg Cu L^(-1). Concentrations of Cu in shoots of E. splendens and E. argyi exceeded 1000 mg kg^(-1)DW at >= 40 mg Cu L^(-1). The maximum Cu accumulated in the shoots of Cu-treated E. splendens and *** reached 101 and 142 mu g plant^(-1). Furthermore, analysis of plant samples from the fieldsshowed that these two ecotypes can tolerant excess heavy metals and produced high dry matter, and *** can accumulate 11.7 mg Cu plant^(-1) grown on the Cu smelter. Therefore, E. splendens *** could be good plants for phytoremediation.

关键词： copper Elsholtzia argyi Elsholtzia splendens

试以朱熹心性思想解析《山琴况》“声中求静”琴乐美学命题

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中国哲学史 2021年第4期 66-73页

作者：欧阳霄武汉大学哲学院

古琴音乐的审美典范经历了从写悲到求静的转变。十七世纪琴学集大成作品徐青山的《溪山琴况》明确提出了"声中求静"的命题。朱熹心性论思想导向一种功夫论倾向,观照作为原因性存在的"心之体",从而提升个体的德性修养,强化"性"在道德实... 详细信息

古琴音乐的审美典范经历了从写悲到求静的转变。十七世纪琴学集大成作品徐青山的《溪山琴况》明确提出了"声中求静"的命题。朱熹心性论思想导向一种功夫论倾向,观照作为原因性存在的"心之体",从而提升个体的德性修养,强化"性"在道德实践中的控制力。《琴况》所言"静由中出"的"中",正是"乐由中出故静"和"喜怒哀乐之为未发谓之中"的"中",指诸情未发之前心灵的状态。"声中求静"命题更深刻的含义即在音乐艺术实践中"体验未发"。

关键词：古琴声中求静乐记朱熹心性论体验未发