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221.
本文运用文献资料、调查访问等方法,对竞技武术套路新旧竞赛规则进行对比,并分析探讨新规则的实施对武术套路训练的影响,提出对此所应采取的训练方法和策略,同时对竞技武术套路动作创新的科学性、新颖性、针对性、技击、美学等原则与难度递进法、组合法、象形法等方法进行了论述,以拓宽武术动作创新的思路,为竞技武术套路动作的创新提供理论依据。  相似文献   
222.
夜光藻赤潮与环境因子关系的模糊分析   总被引:1,自引:0,他引:1  
针对在2006年夏天渤海湾赤潮重点监控区中发生的一次夜光藻赤潮,考虑到夜光藻赤潮过程与环境因子的复杂关系和赤潮监测数据的不确定性,利用模糊逻辑方法对监测数据样本进行了分析。本文的研究对象为1号、2号和4号站位包含有夜光藻赤潮过程的7月26日~8月20日的连续监测数据,给出了隶属度函数和模糊规则的提取方法,利用生成的模糊逻辑规则阐述了此次夜光藻赤潮的生消过程并分析了夜光藻赤潮与若干环境因素之间的变动关系,为进一步研究该海域的夜光藻赤潮机理并预测夜光藻赤潮奠定了基础。  相似文献   
223.
采用自制垃圾填埋甲烷测量装置对衡阳某垃圾处理站临时堆放的处于发酵期的垃圾开展浓度测定试验,探究垃圾填埋气中甲烷在短期内产生的时空规律。结果表明:填埋场中甲烷浓度存在明显的气体分层现象,其浓度主要与纵向填埋深度呈正相关,与距填埋场边界的水平距离呈负相关;填埋初期,距离地表越近,同一水平方向甲烷浓度在不同区域变化较大,随着填埋时间的增长其浓度变化趋于稳定;填埋场内部温度与垃圾埋深和外界温度成线性相关,并且与垃圾埋深成反比,与外界温度成正比。  相似文献   
224.
Active adaptive management is the centerpiece of a major species recovery program now underway on the central Platte River in Nebraska. The Platte River Recovery Implementation Program initiated on January 1, 2007 and is a joint effort between the states of Colorado, Wyoming, and Nebraska; the U.S. Department of the Interior; waters users; and conservation groups. This program is intended to address issues related to endangered species and loss of habitat along the Platte River in central Nebraska by managing land and water resources and using adaptive management as its science framework. The adaptive management plan provides a systematic process to test hypotheses and apply the information learned to improve management on the ground, and is centered on conceptual models and priority hypotheses that reflect different interpretations of how river processes work and the best approach to meeting key objectives. This framework reveals a shared attempt to use the best available science to implement experiments, learn, and revise management actions accordingly on the Platte River. This paper focuses on the status of adaptive management implementation on the Platte, experimental and habitat design issues, and the use of decision analysis tools to help set objectives and guide decisions.  相似文献   
225.
The Suzhou Creek Rehabilitation Project (SCRP) is one of the largest water-related environmental rehabilitation schemes ever undertaken in the vicinity of Shanghai, China. This paper details the development and application of a River Environmental Decision Support System (REDSS) for scientific planning and decision-making on the Suzhou Creek project, and illustrates the flexibility of the REDSS framework. We developed the following components: (1) a GIS-based analysis employing Component technology; (2) a "data mart" for multi-dimensional, multi-level, integrated, dynamic, and flexible data querying; and (3) a set of hydrodynamic and water quality models which can simulate complex tidal river networks. In addition, we detail how a water quality assessment model is embedded into the REDSS by employing an Identification Index Method. With the REDSS, all GIS and non-GIS components are integrated seamlessly and data from different sources can be queried simultaneously. This allows for various scenarios to be simulated and analyzed in advance to predict and assess the effects of proposed engineering and management measures. Generated information can thus support effective decisions. All operations of the REDSS can be implemented conveniently through user-friendly interfaces. The function of the REDSS framework is demonstrated through an application to Suzhou Creek. Because the REDSS characteristics are quite general, it may be applied in different geographic regions.  相似文献   
226.
以鼎湖山3个南亚热带森林演替典型阶段生态系统为对象,采用我国《森林生态系统服务功能评估规范》(LY/T 1721—2008)标准化计算公式与服务价格,量化揭示南亚热带森林生态系统演替过程中生态系统服务功能价值动态。结果表明:随着演替的进行,南亚热带森林生态系统服务功能总价值不断增大;但各分项服务功能价值则表现出不同的动态规律与变化幅度,从而使得森林生态系统服务结构呈现非线性演化特征。在南亚热带森林生态系统演替的早期阶段,生态系统服务价值的最大组分是涵养水源的功能价值,而中、后期则是保育土壤。人工林营造可以有效增强区域生态系统的水源涵养能力,而保育演替中、后期森林则对于大气CO2收和土壤保育而言尤为重要。  相似文献   
227.
Different tools, such as a screening matrix or decision framework, are available to select a remediation technology to treat a contaminated site. However, unless these methods can point out the appropriate technology in regards to the decision-maker's knowledge about the contaminated site, they are less useful to evaluate both the technical effectiveness and the cost of the remediation, and to assess different remediation strategies from either future data acquisition or the use of an irreversible remediation technology. A model developed to allow such evaluations has been used to simulate the remediation of a virtual contaminated site. From this, four remediation recommendations have been made. These recommendations are guidelines for the build up of a remediation strategy that would both maximize the effectiveness of the decontamination and minimize its total cost.  相似文献   
228.
企业安全生产责任制的建立与落实研究   总被引:1,自引:1,他引:0  
以某中央企业集团公司为例,从安全生产责任制的理论体系、国家的安全生产管理体制、企业安全生产的保障原则等入手,系统阐述企业在建立与落实安全生产责任制过程中的一些要点、难点,为企业安全生产责任制的建设提供借鉴,也为企业管理者的管理决策起到了一定的参考作用。  相似文献   
229.
As larvae, solitary species of parasitoid wasps eliminate rivals, including sibs, through contest competition. In gregarious species, larvae tolerate each other and several individuals can develop from a single host. We report experiments on two congeneric braconid species aimed at understanding how gregarious development evolved in one genus, and the consequences of larval interactions for parental behavior. In the transition from solitary to gregarious development, one possible intermediate stage is if solitary species frequently lay more than one egg per host. If the risk of conspecific superparasitism (another female of the same species oviposits into a single host) is high, optimal clutch size theory predicts the laying of multiple-egg clutches, because a female will increase the probability of the surviving larva being her own. Under the same conditions, theory predicts that gregarious species should reduce their clutch size. In our experiments, the solitary Aphaereta genevensis increased their clutch size under the risk of intraspecific competition for hosts whilst the gregarious A. pallipes reduced their clutch size, as predicted. In A. genevensis, the response to the risk of competition was dependent upon body size, being greatest amongst small females. In A. pallipes, the response did not depend on female body size, but clutch size increased with body size in all treatments, unlike in A. genevensis. Under the risk of competition from the other species, the response differed relative to the intraspecific treatments and differed between species. Thus, our data suggest that: (1) competition for hosts may have contributed to the evolution of gregarious development in this genus; (2) female wasps can combine information from both external and internal cues in complex ways during clutch size adjustment; and (3) the social environment may alter the adaptive response to both external and internal cues in adult females.Communicated by M. Elgar  相似文献   
230.
Responding to global change represents an unprecedented challenge for society. Decision makers tend to address this challenge by framing adaptation as a decision problem, whereby the responses to impacts of change are addressed within existing decision processes centred on defining the decision problem and selecting options. However, this ‘decision-making perspective’ is constrained by societal values and principles, regulations and norms and the state of knowledge. It is therefore unsuitable for addressing complex, contested, cross-scale problems. In this paper we argue that simply broadening the decision-making perspective to account for institutions and values is not enough. We contend the decision-making perspective needs to be connected with a broader ‘decision-context perspective’ that focuses on how the societal system of decision processes affects the manner in which a particular problem is addressed. We describe the decision context as an interconnected system of values, rules and knowledge (vrk). The interaction of systems of vrk both creates and limits the set of practical, permissible decisions; the types of values, rules and knowledge that influence the decision and the capacity for change and transformation in the decision context. We developed a framework to analyse the interactions between values, rules and knowledge and their influence on decision making and decision contexts of adaptation initiatives, and applied it retrospectively to three projects on adaptation to sea-level rise. Our analysis revealed: (1) specific examples of how interactions between vrk systems constrained existing framings of decision making and the development of options for coastal adaptation; (2) limitations in the adaptive management strategies that underpinned the projects and (3) how the linked systems of vrk can allow adaptation practitioners to structure adaptation as a process of co-evolutionary change that enables a broader set of social issues and change processes to be considered. Adaptation projects that focus on the decision context represent a pragmatic alternative to existing decision-focused adaptation. By using the vrk model to diagnose constraints in decision processes, we show how the reframing of adaptation initiatives can reveal new approaches to developing adaptation responses to complex global change problems.  相似文献   
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