基于分形理论的江苏沿江城镇体系研究

开放条件下,“全球 地方”作用深刻影响着区域城镇体系,沿江发达地区表现尤其典型。基于分形的相关理论和方法,以2006年为时空断面,对江苏沿江地区城镇体系的空间分布进行实证研究。结果表明：（1）区域城镇规模等级结构服从Zipf定律,首位城市南京在区域城市体系中的垄断性相对较强,但并非处于绝对垄断地位;（2）空间关联维数显示,沿江地区城镇体系的交通网络通达性优良,各城镇间联系紧密;（3）根据分维数和无标度区分析,三大城市群中,宁镇扬城市群分形发育最好,苏锡常次之,通泰城市群分形发育最差;（4）扬州、镇江、南京和苏州的城镇集聚程度较高,分形发育较为成熟;南通、泰州、无锡和常州的集聚程度均较低,分形结构不佳。扬州在区域城镇体系中分形发育最为完善,中心性最好,历史上形成的这种空间格局至今没有变化.     

基于复合生态系统理论的长沙湘江滨水区景观资源评价与优化

近年来,随着我国经济的飞速发展、社会经济的转型,以及人们环境意识的提高,滨水区开发已成为我国城市开发建设的热点。城市滨水区景观规划设计研究对于合理、充分利用城市滨水区景观资源,塑造特色鲜明的城市形象,提高城市生态环境质量,促进城市滨水区开发有着重要意义。从复合生态系统理论的角度,在湘江滨水区景观资源调查、景观资源分类的基础上,运用灰色聚类法对湘江滨水区景观资源进行定量评价,提出景观资源优化思路,探讨滨水区景观规划设计的途径。认为现代城市大规模滨水区更新改造和开发大背景下的城市滨水区景观规划设计,应尊重城市地域性特点、文化内涵和风土人情,并与传统的滨水活动有机结合,保护和突出城市历史格局和风貌特色。     

Diffusion of innovative agricultural production systems for sustainable development of small islands: A methodological approach based on the science of complexity

In order to develop small islands, not only must a vital agricultural system be maintained, but the range of opportunities for tourism must be increased with respect to both the seaside and the environmental features of the rural landscape. As an alternative to the traditional and economically declining ones, many innovative production processes can be identified, but their success depends on their interaction with the physical, biological, economic and social environment. In order to identify the main nodes and the most critical interactions, so as to increase the probability of success of a new productive process, a methodological approach based on the science of complexity is proposed for the cultivation of capers (Capparis spinosa L.) on the island of Pantelleria. The methodology encompasses the identification of actors and factors involved. the quantitative evaluation of their interactions with the different stages of the productive process, and a quasiquantitative evaluation of the probability that the particular action will be performed successfully. The study of “traditional,” “modernized,” and “modernized-sustainable” processes, shows that the modernized-sustainable process offers mutually reinforcing opportunities in terms of an integrated development of high-quality agricultural products and the enhancement of environmental features, in conjunction with high-efficiency production techniques, in conjunction with high-efficiency production techniques, in a way that suits the development of Pantelleria. There is a high probability of failure, however, as a result of the large number of critical factors. Nevertheless, the present study indicates which activities will enhance the probability of successful innovation in the production process.     

卡尔曼滤波理论在预报地面径流污染中的应用

本文主要介绍流域径流污染的系统分析方法，并提出采用卡尔曼滤波理论进行仿真，从而实现污染的预报。     

Incorporating Collateral Data in Conservation Biology

Abstract:  Conservation biologists often need to set ecological modeling assumptions or estimate parameters from sparse data. In some cases this problem can be addressed by incorporating data from closely related species or from the same species at different sites (i.e., collateral data). Currently no structured methods exist for incorporating such information. An analogous problem in Actuarial science is to set premium rates in situations with little direct data on claim frequency or size. The rates are estimated using actuarial credibility theory, which incorporates collateral data with the direct data. actuarial credibility theory combined with the actuarial control cycle financial management process also provides an adaptive mechanism for updating assumptions. This theory may have some utility for ecologists wanting to incorporate collateral data in an adaptive management framework, a companion to approaches such as Bayesian updating. We describe the historical development of actuarial credibility theory from early ad hoc methods to empirical Bayes approaches. We explore some of the theory's strengths, such as relative simple formulae for incorporation collateral data, and we explore some of the theory's weaknesses, such as the use of the best linear approximation to the Bayes estimate. We illustrate potential applications of the theory using an example on the mortality rate of the Powerful Owl (  Ninox strenua ).     

Risk-taking by female ducks: intra- and interspecific tests of nest defense theory

We tested several predictions of nest defense theory by observing variation in flushing distance and probability of nest abandonment within and between six species of waterfowl. In these species, only the females incubate eggs and attend offspring. First, we examined whether flushing distance by females varied in relation to clutch size, stage of incubation, and time of season, after controlling for the number of visits made to nests by observers. Revisits by observers appeared to affect flushing distance by females for reasons unrelated to the relative value of the current clutch. We found that as incubation progressed, females allowed observers to approach more closely before flushing from the nest. In some species, females with larger clutches allowed closer approaches to nests before flushing which was also consistent with nest defense theory. In contrast, time of season (Julian date) did not relate to flushing distance for any species. When species were compared, we found that species with moderate to high yearly mortality and high reproductive output per breeding attempt (e.g., northern shoveler and blue-winged teal) were less likely to abandon nesting attempts and exhibited riskier behavior (remained at nests when approached closely by observers) than species that had lower yearly mortality (e.g., mallard). Our results show that flushing distance and patterns of nest abandonment by female ducks conform to several predictions of nest defense theory.Correspondence to: M.R.L. Forbes     

A vaccination game based on public health actions and personal decisions

Susceptible-infective-removed (SIR) models are commonly used for representing the spread of contagious diseases. A SIR model can be described in terms of a probabilistic cellular automaton (PCA), where each individual (corresponding to a cell of the PCA lattice) is connected to others by a random network favoring local contacts. Here, this framework is employed for investigating the consequences of applying vaccine against the propagation of a contagious infection, by considering vaccination as a game, in the sense of game theory. In this game, the players are the government and the susceptible newborns. In order to maximize their own payoffs, the government attempts to reduce the costs for combating the epidemic, and the newborns may be vaccinated only when infective individuals are found in their neighborhoods and/or the government promotes an immunization program. As a consequence of these strategies supported by cost-benefit analysis and perceived risk, numerical simulations show that the disease is not fully eliminated and the government implements quasi-periodic vaccination campaigns.     

可持续发展的突变评判法

首次将系统新三论之一的突变理论应用于可持续发展评价的研究中。介绍了突变评判法的基本原理和使用步骤，并运用该方法对天津市的可持续发展状态进行了评价。     

A Decision Framework for the Adaptive Management of an Exploited Species with Implications for Marine Reserves

Abstract:  Marine reserves have both conservation and fishery benefits. Nevertheless, there are no general criteria about when and where to establish new reserves, how to evaluate their efficacy, and how to conduct adaptive management to achieve conservation goals. We applied a decision-theory framework to optimally allocate conservation resources between improving data on population status and establishing a reserve for species conservation. Our goal was to maximize reserve benefits given the constraints of a population growth rate that would permit sustainability of resources. We illustrate our decision framework with a retrospective analysis of a 7-year time series on abundance of the leopard grouper ( Mycteroperca rosacea ) in the Sea of Cortés, Mexico. We used the lower bound of the distribution of the population growth rate ( λ ) as a decision rule for determining how many years of monitoring are needed to detect reserve effects. We determined the minimum time frame needed to estimate λ based on a stated level of risk tolerance for four sites. As expected, the coefficient of variation for the λ declined with the number of years of data. This increased precision with additional years of data resulted from the high degree of annual variability in the system. Where populations were slow to respond to reserves, more data were needed to detect a positive λ value. For the leopard grouper case study, confidence in the estimate of λ increased with the number of years of data. Our decision framework may be used to identify the minimum number of years of data needed before a management decision about reserve establishment could be made that is reasonably likely to meet its management objectives.     

基于混沌理论的海南旅游业危机预警机制构建

基于混沌理论构建旅游业危机预警机制是防治旅游业危机的有效手段。阐述了旅游业危机理论、混沌理论和旅游业危机预警机制理论,剖析了海南2007--2010年旅游业危机事件,建立了海南旅游业危机评价指标体系、危机预警机制、危机防治综合管理机制和教育与宣传等系统。研究表明,防治旅游业危机事件,关键是重视旅游行业初期敏感性,对初始值进行有效控制,而建立危机预警机制、危机防治综合管理机制和加强教育与宣传是其核心内容。