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211.
Aaron Christ Jay Ver Hoef Dale L. Zimmerman 《Environmental and Ecological Statistics》2008,15(1):27-38
Wildlife biologists are often interested in how an animal uses space and the habitat resources within that space. We propose
a single model that estimates an animal’s home range and habitat selection parameters within that range while accounting for
the inherent autocorrelation in frequently sampled telemetry data. The model is applied to brown bear telemetry data in southeast
Alaska.
This article is based on a portion of this author’s Ph.D. dissertation completed in 2003 at the University of Iowa. 相似文献
212.
Modern ecologico-cybernetic principle is of importance to decreasing damages in relation to agricultural productions. As an illustration of this, the authors studied some of the questions about the optimal policy of choosing actions for the antifrost measures of winter wheat by means of the finite-stage model of Markov Decision Programming (MDP). The related data came from the investigation results of the investigated region in the northeastern part of Henan, China. First, the authors give the states, ecologico-cybernetic action measures, transition probabilities and reward values in relation to these antifrost action measures of winter wheat crop. Second, the authors describe the principles and computational procedures of the ecologico-cybernetic decision-makings based on the finite-stage model of MDP. Third, a simple table applicable to the decision-making practice is given. Finally, we evaluate the results of this study, point out their shortcomings and suggest that this method is applicable to the other fields in relation to decreasing damage ecologico-cybernetics. 相似文献
213.
中国传统的室内设计具有中国传统文化的一切特征,不管是空间的布局,还是装饰风格,都体现其内在的含蓄风格,在整体意境及设计理念上追求天人合一的自然和谐,同时也是传统建筑有机的组成部分。中国传统的设计元素越来越多地被当今世界设计师所借鉴。 相似文献
214.
Summary This study suggested that cell-cycle kinetics, DNA replication and DNA repair react to magnetic fields differently. During
their culture growth cycle, which lasted about five days, Friend erythroleukemia cells were either kept in the absence of
magnetic fields in a magnetically shielded room or irradiated in a solenoid with 70 μT at 50 Hz plus 45 μT DC of the Earth:
some cells grew without inducer of in vitro differentiation; others were induced to differentiate hemoglobin through dimethylsulfoxide. It emerged that, during a single
culture growth cycle, while proliferation was slightly accelerated by the magnetic-field irradiation achieved in the solenoid
both in undifferentiating and dimethylsulfoxide-differentiating cells, DNA replication did not appear to significantly depend
on the magnetic-field deprivation achieved in the magnetically shielded room. However, as a result of a 318-day long magnetic-field
irradiation in the solenoid, DNA replication remained unchanged in undifferentiating cells and partially inhibited in dimethylsulfoxide-differentiating
cells. Following the same long magnetic-field irradiation in the solenoid, the amount of labelled repair patches in the parental
DNA strands was slightly reduced. 相似文献
215.
分有人介入和无人介入重大危险源监测系统两种情况,运用马尔可夫过程研究了重大危险源发生事故的概率,并进行了实例计算。所给概率模型可用于重大危险源的安全评价。【关键词】##4易燃易爆重大危险源;;马尔可夫过程;;安全评价;;事故概率计算;;安全监测系统 相似文献
216.
环境风险预测数学模型 总被引:2,自引:0,他引:2
张玉青 《中国环境管理干部学院学报》2002,12(1):26-29
本文基于环境风险预测分析的基本思想,应用模糊图、灰色系统、非线性回归、随机过程和可靠性系统工程理论和方法,探讨了环境风险预测的数学模型。给出了环境风险预测的双向模糊图模型、灰色马尔夫预测模型及非线性回归模型,这些模型的应用为环境风险评价和环境风险管理提供了科学依据。 相似文献
217.
218.
简易柱式无土栽培法 总被引:3,自引:0,他引:3
在立柱栽培技术发展过程中 ,简易柱式法最先是在 1994~ 1995年初发展起来的 ,并在当年推广到江苏张家港市和河北遵化市 ,后来在此基础上发展了现被广泛推广应用的标准型柱式无土栽培法[1~ 3] ,但该方法中的盆钵是由高强度抗老化的ABS工程塑料铸塑而成 ,价格贵 ,安装 1亩 ( 6 6 6 .7m2 )约需6万元人民币 ,在中小城市及农村推广使用不易 ,因此简易柱式无土栽培技术的优点值得重视 ,讨论如下 :1 简易立柱的组装简易柱是由包裹材料柱壁、柱体和栽培基质构成 .柱壁是新制丙烯 (polypropyrene)编织材料 (俗称“蛇皮”带 ) ,裁… 相似文献
219.
Willem Kruijer Alfred Stein Willem Schaafsma Sanne Heijting 《Environmental and Ecological Statistics》2007,14(4):399-410
Count data on a lattice may arise in observational studies of ecological phenomena. In this paper a hierarchical spatial model
is used to analyze weed counts. Anisotropy is introduced, and a bivariate extension of the model is presented. 相似文献
220.
ABSTRACT: A major objective of this work was to develop a method applicable to the Intermountain region for estimating the probability of n consecutive dry days, where n ≤ 30 days. One result was a computationally simple method of producing the desired estimates directly from the rainfall record. For a consecutive dry-day period of n days, these estimates are equivalent to those obtained from a Markov model of order n-1. The efficacy of a simple Markov model was also evaluated. In this climatic region, the simple Markov model produces probability estimates of consecutive dry days that are too conservative, especially at long dry-day periods. In this data set, it was found that the longer the dry-day sequence, the more conservative the Markov estimate. The source of these conservative estimates is the strong dry-day persistence, which is characteristic of summer weather in the Intermountain region. In this region, the best estimates of the probability of consecutive dry days are probably those obtained directly from a representative rainfall record and smoothed by the partial sums of a fourier Series. 相似文献