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991.
Monitoring Sustainable Forest Management in Different Jurisdictions   总被引:1,自引:0,他引:1  
The concept of sustainable forest management (SFM) requires forest resource managers to monitor and collect information pertaining to their environmental, economic and social impact. There are increasing expectations from a variety of publics (government, customers, and other stakeholders) that forests be demonstrably well-managed, creating incentives for forest managers to design credible systems for assessing their management performance. It is against this background that local, national and international approaches to regulating forest practices have been evolving. This article reviews the different dimensions of governance as they relate to monitoring and information reporting in the forest sector. Specifically, it discusses the changing role of sovereignty, the effects of globalization and the emergence of civil society stakeholders in forestry-related decision-making. Concepts such as sovereignty and globalization have important implications for monitoring forest practices and for defining SFM. Whether SFM standard creation and enforcement involves a sovereign, shared-sovereignty or civil society approach will affect the level and nature of SFM monitoring. As a result, we need to better consider the concept of monitoring appropriate to the scale and intensity of operations, how monitoring and information reporting standards differ between jurisdictions, and what this means for independently verifying SFM at an inter-jurisdictional level.  相似文献   
992.
基于徐州市2013年12月—2018年11月的空气质量指数日均值,建立了时间序列自回归输入的GA-BP神经网络模型用于空气质量指数预测。结果表明,所建立的网络模型能够准确预测徐州市空气质量指数的变化趋势,其中夏季预测相对误差18. 23%,仿真均方根误差(RMSE)为14. 59;冬季预测相对误差9. 14%,仿真RMSE为11. 47。  相似文献   
993.
In order to resolve the spatial component of the design of a water quality monitoring network, a methodology has been developed to identify the critical sampling locations within a watershed. This methodology, called Critical Sampling Points (CSP), focuses on the contaminant total phosphorus (TP), and is applicable to small, predominantly agricultural-forested watersheds. The CSP methodology was translated into a model, called Water Quality Monitoring Station Analysis (WQMSA). It incorporates a geographic information system (GIS) for spatial analysis and data manipulation purposes, a hydrologic/water quality simulation model for estimating TP loads, and an artificial intelligence technology for improved input data representation. The model input data include a number of hydrologic, topographic, soils, vegetative, and land use factors. The model also includes an economic and logistics component. The validity of the CSP methodology was tested on a small experimental Pennsylvanian watershed, for which TP data from a number of single storm events were available for various sampling points within the watershed. A comparison of the ratios of observed to predicted TP loads between sampling points revealed that the model's results were promising.  相似文献   
994.
随着新技术的发展和计算机的广泛应用,知识产权领域出现了许多前所未有的新课题,域名的知识产权保护问题即是其中之一。对域名的含义、域名与商标的法律关系以及如何认定注册、使用域名等行为构成侵权或者不正当竞争等问题进行了分析。  相似文献   
995.
Socially Responsible Investing (SRI) has carved out a niche in the financial world, and each year a large number of shareholder proposals are filed at public companies in the US related to issues of corporate social responsibility (CSR). While the primary interests of CSR activists remain distinct from those of traditional corporate governance (CG) activists, the two groups do share an interest in minimizing the risk of negative environmental or social impacts from the operations of the corporation. They also share the objective of achieving transparency and accountability in corporate decision‐making. In relation to this latter objective, they both face similar challenges concerning conflicts of interest among key institutional shareholders. This article examines the record of shareholder proposal filing and voting from 2000–2003 for 81 large US public corporations to determine the relative prominence of CSR shareholder activism and the prospects for effective CSR shareholder activism on key environmental issues. The analysis of these data finds that nearly half (45%) of all shareholder resolutions are related to CSR, and that those resolutions which combine issues of CSR with traditional CG activism appeal to slightly more shareholders than issues of CSR alone. The article also examines shareholder activism at the micro level with a case study of the voting record at ExxonMobil. The article finds that CSR‐related shareholder activism represents the majority of shareholder activism within that firm and that resolutions targeted at climate change are particularly well supported. These resolutions draw a connection between environmental risk and risk to shareholder value. While numerous challenges remain for both CG and CSR activists, the article concludes that reforms that strengthen shareholder rights and corporate governance more generally will also benefit CSR activists and the environmental policies they promote in particular. The article ends with some proposed solutions for addressing the perceived conflicts of interest in corporate governance and the shareholder voting process.  相似文献   
996.
基于BP神经网络的垃圾堆放场稳定化程度的综合判别   总被引:2,自引:0,他引:2  
分析和判别垃圾堆放场的稳定化程度直接关系到是否需要采取加快稳定化进程,缩短垃圾堆放场的稳定化周期以及是否需要采取措施减少它们对环境的不利影响。本文根据我国垃圾堆放场的具体情况,提出稳定化程度的判别评价指标体系,并且确定稳定化程度的判别标准,运用BP神经网络建立垃圾堆放场稳定化程度的综合判别模型。以三峡库区的一个小型垃圾堆放场为例,采用本文所提出的综合评价模型确定它的稳定化程度,演示模型的运行过程,并为三峡库区的环境保护提供帮助。  相似文献   
997.
浅谈网络安全策略   总被引:1,自引:0,他引:1  
由于计算机网络表现的脆弱性使网络容易受到各种攻击,所以网络信息的安全和保密是一个非常重要的问题。本文从计算机网络安全策略出发,对解决计算机网络安全策略原则及网络的安全技术进行了综述。  相似文献   
998.
三峡水库自 2 0 0 3年蓄水后 ,水对斜坡 (滑坡 )的软化作用和库岸再造大大改变了库区的工程地质条件 ,库区的地质灾害严重制约了库区移民迁镇工程 ,场地建筑安全评价显得尤为重要。笔者根据库区工程地质的特点 ,提出了场地建筑适宜性评价的指标体系 ,建立了场地建筑安全评价人工神经网络模型。通过对红石包滑坡进行各种工况下的稳定性评价 ,利用稳态坡形、坡角工程地质类比法对红石包进行库岸再造的预测 ,对三峡库区巴东县新城区红石包油库建筑进行安全评价。为库区移民迁镇工作提供科学依据。  相似文献   
999.
计算机网络安全的防范措施   总被引:2,自引:0,他引:2  
随着传播媒体和信息技术高速发展,Internet广泛应用,共享信息与网上业务在不断增加。伴随而来的网络攻击和犯罪日益猖橛。本文概要地介绍了网络信息安全面临的主要威胁,阐述了计算机网络安全的基本防范措施。  相似文献   
1000.
基于神经网络的煤矿底板突水预测   总被引:6,自引:0,他引:6  
江东  陈佩佩 《灾害学》1999,14(1):28-32
阐述了运用人工神经网络建立煤矿底板突水预测模型的思路与方法,并以山东国家庄煤矿为例,对该方法的合理性和准确性进行了验证.研究表明,利用人工神经网络建立非线性系统的预测模型,具有自学习、自适应、精度高等显著优点.  相似文献   
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