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141.
Space-time modeling for the Missouri Turkey Hunting Survey 总被引:1,自引:0,他引:1
The Missouri Turkey Hunting Survey (MTHS) is a postseason mail survey conducted by the Missouri Department of Conservation. The 1996 MTHS provides information concerning the number of turkeys harvested by hunters on each day and the total number of trips made to the counties by these hunters on each day of the hunting season. The success rates are then found from this information. Small sample sizes produce large standard errors for the estimates at the county level. We use a Bayesian hierarchical generalized linear model to estimate daily hunting success rates at the county level. The model includes an autoregressive process for the days of the hunting season and spatially correlated random geographic effects. The computations are performed using Gibbs sampling and adaptive rejection sampling techniques. Results show that there are significant spatial corelations between counties and correlations between days of the hunting season. The estimates are close to the frequency estimates at the state level and much more stable at the county level. 相似文献
142.
Haolan Lu Cavan S. Reilly Sudipto Banerjee Bradley P. Carlin 《Environmental and Ecological Statistics》2007,14(4):433-452
Recently, public health professionals and other geostatistical researchers have shown increasing interest in boundary analysis, the detection or testing of zones or boundaries that reveal sharp changes in the values of spatially oriented variables.
For areal data (i.e., data which consist only of sums or averages over geopolitical regions), Lu and Carlin (Geogr Anal 37: 265–285,
2005) suggested a fully model-based framework for areal wombling using Bayesian hierarchical models with posterior summaries
computed using Markov chain Monte Carlo (MCMC) methods, and showed the approach to have advantages over existing non-stochastic
alternatives. In this paper, we develop Bayesian areal boundary analysis methods that estimate the spatial neighborhood structure
using the value of the process in each region and other variables that indicate how similar two regions are. Boundaries may then be determined by the posterior distribution
of either this estimated neighborhood structure or the regional mean response differences themselves. Our methods do require
several assumptions (including an appropriate prior distribution, a normal spatial random effect distribution, and a Bernoulli
distribution for a set of spatial weights), but also deliver more in terms of full posterior inference for the boundary segments
(e.g., direct probability statements regarding the probability that a particular border segment is part of the boundary).
We illustrate three different remedies for the computing difficulties encountered in implementing our method. We use simulation
to compare among existing purely algorithmic approaches, the Lu and Carlin (2005) method, and our new adjacency modeling methods.
We also illustrate more practical modeling issues (e.g., covariate selection) in the context of a breast cancer late detection
data set collected at the county level in the state of Minnesota. 相似文献
143.
虚拟生态产业链的稳定性研究 总被引:1,自引:0,他引:1
以虚拟产业链的稳定性作为研究的着力点,对影响虚拟产业链的稳定性的风险因素进行分析,其中包括市场风险因素、技术成本风险因素、交易风险因素等,针对这些影响因素,并给出风险防范体系,即虚拟产业链的风险防范内生体系和外生体系:内生体系是指在虚拟产业链的本身内部网络中建立的风险防范机制、对策、方法措施等,如检查机制、激励机制、利润/风险分担机制和清算机制,而外生体系是指对虚拟生态产业链的风险起防范作用的法律法规、信用和传媒等社会体系的总和。从而从生态产业链内外部整体资源的协同利用和利益相关者的协同效用两方面来提高虚拟产业链的稳定性。 相似文献
144.
从系统论、信息论的角度探讨了违法排污事件屡禁不止的原因,并分析了当前环境管理系统中信息传递中存在的问题,提出了完善当前环境管理系统中信息链的具体措施. 相似文献
145.
Paolo Gasparini Giuseppe Novelli Anna Savoia Bruno Dallapiccola Pier Franco Pignatti 《黑龙江环境通报》1989,9(5):349-355
Eight pregnancies at risk for cystic fibrosis have been monitored by first-trimester prenatal diagnosis with DNA amplification analysis. The polymerase chain reaction (PCR) was used in all cases to amplify the region detected by KM 19. In two cases, the region detected by CS·7, another DNA probe tightly linked to the CF locus, was also examined. The results of the PCR determinations were confirmed using the Southern blotting procedure, by segregation analysis of restriction fragment length polymorphisms (RFLPs) relative to XV-2c, J3·11, metH, metD, and KM19 probes. 相似文献
146.
应用马尔可夫链分析预测福建以林为主的土地利用趋势 总被引:2,自引:0,他引:2
土地利用状况的研究是国土整治及林业发展规划的重要研究内容,本文根据森林资源连续清查的资料,应用马尔可夫链理论,建立预测模型,分析、预测土壤利用的动态状况,提出宏观控制的对策,为土地利用规划,林业生产决策提供科学的方法与依据。 相似文献
147.
Maciel M. Queiroz 《环境质量管理》2019,28(3):7-15
Sustainable supply chains (SSC) are an essential topic in emerging economies for achieving sustainable development. Because of their rapid economic growth, emerging economies are experiencing both sides of this development: the well‐being enhancement and the environmental impact. However, decision makers and practitioners do not have robust models for managing supply networks that consider the sustainability complexities. This study aims to provide a better understanding of SSC in emerging economies and proposes a generic framework to improve the decision‐making process. Based on a review of the literature, a decision framework for sustainability is proposed. A green sustainable decision concept is also discussed in the SSC literature. This study has implications for scholars, decision makers, and practitioners interested in advancing the SSC field based on an extension of the framework. 相似文献
148.
中国旅游业碳排放的影响因素分解及脱钩效应 总被引:1,自引:0,他引:1
采用广义迪氏指数分解法(GDIM)分解2000~2017年中国旅游业碳排放的影响因素,并在此基础上采用Tapio脱钩因果链模型分析旅游业碳排放的脱钩效应.结果表明:旅游业增加值、旅游业能源消耗量和旅客人次数是旅游业碳排放的促增因素,增加值能源强度和人均旅游业增加值是旅游业碳排放的促降因素,增加值碳强度、能源消耗碳强度和人均旅游业碳排放对旅游业碳排放的促增和促降作用在研究期间均有出现;旅游业能源消耗量的累积促增效应最大,为2030.13万t,增加值能源强度的累积促降效应最大,为103.29万t;旅游业碳排放的脱钩状态不佳,但近年来有所改善;人均脱钩弹性波动剧烈,节能弹性的变化是其波动的主要原因. 相似文献
149.
Erik Nordell Anna B. Hansson Martin Karlsson 《Waste management (New York, N.Y.)》2013,33(12):2659-2663
Protein and fat rich slaughterhouse waste is a very attractive waste stream for the production of biogas because of the high biochemical methane potential of the substrate. The material has however some drawbacks as the sole material for biogas production due to the production of several process disturbing metabolites such as ammonia, sulfides and long chain fatty acids. We can in this work present results that show that zeolites have the potential to relieve inhibitory stress from the presence of long chain fatty acids. Moreover, the results strongly indicate that it is mainly acetic acid consumers that are most negatively affected by long chain fatty acids and that the mechanism of stress relief is an adsorption of long chain fatty acids to the zeolites. In addition to this, it is shown that the effect is immediate and that only a small amount of zeolites is necessary to cancel the inhibitory effect of long chain fatty acids. 相似文献
150.
A Comparison of Bayesian Methods for Uncertainty Analysis in Hydraulic and Hydrodynamic Modeling
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René A. Camacho James L. Martin William McAnally Jairo Díaz‐Ramirez Hugo Rodriguez Peter Sucsy Song Zhang 《Journal of the American Water Resources Association》2015,51(5):1372-1393
We evaluate and compare the performance of Bayesian Monte Carlo (BMC), Markov chain Monte Carlo (MCMC), and the Generalized Likelihood Uncertainty Estimation (GLUE) for uncertainty analysis in hydraulic and hydrodynamic modeling (HHM) studies. The methods are evaluated in a synthetic 1D wave routing exercise based on the diffusion wave model, and in a multidimensional hydrodynamic study based on the Environmental Fluid Dynamics Code to simulate estuarine circulation processes in Weeks Bay, Alabama. Results show that BMC and MCMC provide similar estimates of uncertainty. The posterior parameter densities computed by both methods are highly consistent, as well as the calibrated parameter estimates and uncertainty bounds. Although some studies suggest that MCMC is more efficient than BMC, our results did not show a clear difference between the performance of the two methods. This seems to be due to the low number of model parameters typically involved in HHM studies, and the use of the same likelihood function. In fact, for these studies, the implementation of BMC results simpler and provides similar results to MCMC. The results of GLUE are, on the other hand, less consistent to the results of BMC and MCMC in both applications. The posterior probability densities tend to be flat and similar to the uniform priors, which can result in calibrated parameter estimates centered in the parametric space. 相似文献