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1.
普里什文哲理散文中所具有的预言式生态思想与环保理念备受当代“生态文学”理论家的青睐。但他热衷描写狩猎场景的猎人情结却又遭到新世纪中“生态伦理”理论的诟病。其实从文本的本体性观念来理解,普里什文的诗性自然情怀、生态观念与他的猎人情结并非只有冲突的一面,他所表达出的是人对大自然万物之本能与道义之间的尺度衡量,而这种衡量也可反观当代人与自然万物之间的关系的现状,实际上表达出一种更为深刻的天人关系的批判性。  相似文献   
2.
《Risk analysis》2018,38(1):84-98
The emergence of the complexity characterizing our systems of systems (SoS) requires a reevaluation of the way we model, assess, manage, communicate, and analyze the risk thereto. Current models for risk analysis of emergent complex SoS are insufficient because too often they rely on the same risk functions and models used for single systems. These models commonly fail to incorporate the complexity derived from the networks of interdependencies and interconnectedness (I–I) characterizing SoS. There is a need to reevaluate currently practiced risk analysis to respond to this reality by examining, and thus comprehending, what makes emergent SoS complex. The key to evaluating the risk to SoS lies in understanding the genesis of characterizing I–I of systems manifested through shared states and other essential entities within and among the systems that constitute SoS. The term “essential entities” includes shared decisions, resources, functions, policies, decisionmakers, stakeholders, organizational setups, and others. This undertaking can be accomplished by building on state‐space theory, which is fundamental to systems engineering and process control. This article presents a theoretical and analytical framework for modeling the risk to SoS with two case studies performed with the MITRE Corporation and demonstrates the pivotal contributions made by shared states and other essential entities to modeling and analysis of the risk to complex SoS. A third case study highlights the multifarious representations of SoS, which require harmonizing the risk analysis process currently applied to single systems when applied to complex SoS.  相似文献   
3.
Summary.  Wavelet shrinkage is an effective nonparametric regression technique, especially when the underlying curve has irregular features such as spikes or discontinuities. The basic idea is simple: take the discrete wavelet transform of data consisting of a signal corrupted by noise; shrink or remove the wavelet coefficients to remove the noise; then invert the discrete wavelet transform to form an estimate of the true underlying curve. Various researchers have proposed increasingly sophisticated methods of doing this by using real-valued wavelets. Complex-valued wavelets exist but are rarely used. We propose two new complex-valued wavelet shrinkage techniques: one based on multiwavelet style shrinkage and the other using Bayesian methods. Extensive simulations show that our methods almost always give significantly more accurate estimates than methods based on real-valued wavelets. Further, our multiwavelet style shrinkage method is both simpler and dramatically faster than its competitors. To understand the excellent performance of this method we present a new risk bound on its hard thresholded coefficients.  相似文献   
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Like artisans in a professional guild, we evaluators create tools to suit our ever evolving practice. The tools we use as evaluators are the primary artifacts of our profession, reflect our practice and embody an amalgamation of paradigms and assumptions. With the increasing shifts in evaluation purposes from judging program worth to understanding how programs work, the evaluator’s role is changing to that of facilitating stakeholders in a learning process. This involves clarifying purposes and choices, as well as unearthing critical assumptions. In such a role, evaluators become major tool-users and begin to innovate with small refinements or produce completely new tools to fit a specific challenge or context.We interrogate the form and function of 12 tools used by evaluators when working with complex evaluands and complex contexts. The form is described in terms of traditional qualitative techniques and particular characteristics of the elements, use and presentation of each tool. Then the function of each tool is analyzed with respect to articulating assumptions and affecting the agency of evaluators and stakeholders in complex contexts.  相似文献   
6.
We describe methods to detect influential observations in a sample of pre-shapes when the underlying distribution is assumed to be complex Bingham. One of these methods is based on Cook's distance, which is derived from the likelihood of the complex Bingham distribution. Other method is related to the tangent space, which is based on the local influence for the multivariate normal distribution. A method to detect outliers is also explained. The application of the methods is illustrated in both a real dataset and a simulated sample.  相似文献   
7.
特殊的地理位置和气候环境铸造了傣族人民个性鲜明的水情结。文化是各个民族对特定环境的适应能力和适应成果的总和,透过傣族人民的水情结,我们将可以领略到该民族独特的生活习俗、审美追求和民族文化。  相似文献   
8.
从贾樟柯导演的第一部长片电影《小武》开始,其作品多次在各大国际电影节上斩获大奖,这与他坚持以现实主义风格创作是分不开的。他始终用冷静的思维和镜头语言,关注边缘人物的命运,描绘着这个真实世界所发生的故事。文章深入分析其电影《世界》抽象的叙事空间所要揭示的内涵,指出在“草根”情节和“乡愁”意识下,人在寻找自我和社会归属的同时迷失方向,从而对社会产生一定的反作用力而导致了社会的“断层”。  相似文献   
9.
本文运用复杂网络分析方法,从一个全新的角度分析中国A股市场个股的相关性,以2014年至2015年间的股票市场交易数据为基础,以上证180指数成分股股票为样本,构建我国股票市场的复杂网络系统。通过计算分析股票网络的拓扑特征统计量,并与美股成熟市场进行比较,研究我国A股市场个股联动的网络结构;同时,在我国金融市场进一步开放的大背景下,本文通过研究样本股票网络在不同情形攻击下网络结构的变化,探索A股市场不同公司股价波动的联动性规律,为监管者稳定证券市场,特别是在“股灾”等极端情况下维持证券市场的流动性功能提供新的决策参考,以利于中国证券市场更好地为经济转型提供金融支持,保护中小投资者利益。  相似文献   
10.
This paper explores avenues for navigating evaluation design challenges posed by complex social programs (CSPs) and their environments when conducting studies that call for generalizable, causal inferences on the intervention’s effectiveness. A definition is provided of a CSP drawing on examples from different fields, and an evaluation case is analyzed in depth to derive seven (7) major sources of complexity that typify CSPs, threatening assumptions of textbook-recommended experimental designs for performing impact evaluations. Theoretically-supported, alternative methodological strategies are discussed to navigate assumptions and counter the design challenges posed by the complex configurations and ecology of CSPs. Specific recommendations include: sequential refinement of the evaluation design through systems thinking, systems-informed logic modeling; and use of extended term, mixed methods (ETMM) approaches with exploratory and confirmatory phases of the evaluation. In the proposed approach, logic models are refined through direct induction and interactions with stakeholders. To better guide assumption evaluation, question-framing, and selection of appropriate methodological strategies, a multiphase evaluation design is recommended.  相似文献   
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