A note on the projection properties of Hadamard matrices obtained by the first Payley construction

We show that the projections on four factors of an arbitrary orthogonal array of strength 2 allow the estimation of main effects and two-factor interactions when all other effects are assumed to be zero, if those projections satisfy the bounds given by Weils theorem. The only exceptions are the Hadamard matrices of orders 16 and 24. A consequence is again the estimability of main effects and two-factor interactions for the projections on four factors of the first Payley construction for arbitrary run size.     

试论研究环境问题的三种理论框架

本文认为,对环境问题的理论研究大致分三种脉络:外部性与社会福利、公地的悲剧与环境产权、物质平衡模型与可持续发展规划。依据这三种理论框架,解决环境问题的对策措施需要同时从市场机制建设、人类社会发展目标确定与技术途径三个方面展开。     

生态化综合农业技术创新的特征与途径

新农村建设是一项复杂的系统工程。涉及到农业、农村和农民问题的综合解决。以往农业发展中注重技术创新的经济目标的局限性及由此带来的发展与环境的矛盾、经济增长与社会福利失衡的矛盾等是制约“三农”问题解决的瓶颈。因此根据生态科学和生态哲学倡导的整体性、持续性、创造性与和谐性的原则。探索有效的政策制度创新、科学技术创新、工程管理创新、教育体系创新的综合集成。成为新农村建设走向可持续发展的必经之路。     

国有资本预算制度的构建目标、原则与基本框架

我国新型国有资产管理体制的建立,引发了如何对国有资本进行监管的思考,而建立国有资本预算制度是一个重要的措施.本文从国有资本预算制度的财务监管功能定位出发,对国有资本预算制度的构建目标、原则和基本框架进行了研究,并对国有资本预算的编制系统和国有资本预算的审核监督系统进行了深入探讨.     

Integrating ecosystem services into conservation assessments: A review

A call has been made for conservation planners to include ecosystem services into their assessments of conservation priority areas. The need to develop an integrated approach to meeting different conservation objectives and a shift in focus towards human wellbeing are some of the motivations behind this call. There is currently no widely accepted approach to planning for ecosystem services. This study contributes towards the development of this approach through a review of conservation assessments and the extent to which they include ecosystem services. Of the 476 conservation assessments identified by a set of search terms on the Web of Science, 100 were randomly selected for this review. Of these only seven had included ecosystem services, while another 13 had referred to ecosystem services as a rationale for conservation without including them in the assessment. The majority of assessments were based on biodiversity pattern data while 19 used data on ecological processes. A total of 11 of these 19 assessments used processes, which could be linked to services. Ecosystem services have witnessed an increase in attention received in conservation assessments since the year 2000, however trends were not apparent beyond this date. In order to assess which types of ecosystem services and how they have been accounted for in conservation assessments, we extended our review to include an additional nine conservation assessments which included ecosystem services. The majority included cultural ecosystem services, followed by regulatory, provisioning and supporting services respectively. We conclude with an analysis of the constraints and opportunities for the integration of ecosystem services into conservation assessments and highlight the urgent need for an appropriate framework for planning for ecosystem services.     

亚洲石油大陆桥建设设想

本文提出了关于建设亚洲石油大陆桥设想的国际意义,以及我国参与建设的必要性,并构建了亚州石油大陆桥的基本框架,最后提出中国应采取的主要对策和措施.     

"建筑节地"理念在城市化进程中的诠释

目前我国城市建设用地规模不断扩张，导致耕地资源严重不足，如何节约用地．就成为城市化进程中的首要问题。因此，在城镇建设过程中要贯彻“建筑节地”理念．合理确定城市用地规模。发达国家城市化进程中占用耕地状况或许能够给我们一些启示。     

山一生态村建设的成绩与思考

山一村自８０年代初建设生态村以来，在控制人口增长，美化。改善生态环境等方面取得了令人瞩目的成绩。然而由于各种原因使资源的多层次利用没有取得突破性的进展。对此，笔者提出要加强实用高效多种生态技术的研究。     

Theory and practice of monetary policy

Summary. We consider an optimally managed renewable resource with stochastic non-concave growth function. We characterize the conditions under which the optimal policy leads to global extinction, global conservation and the existence of a safe standard of conservation. Our conditions are specified in terms of the economic and ecological primitives of the model: the biological growth function, the welfare function, the distribution of shocks and the discount rate. Our results indicate that, unlike deterministic models, extinction and conservation in stochastic models are not determined by a simple comparison of the growth rate and the discount rate; the welfare function plays an important role.Received: 20 October 2004, Revised: 28 February 2005, JEL Classification Numbers: D90, O11, O41, Q32.Santanu Roy: Correspondence toResearch on this paper was completed when the second author visited Cornell University in July, 2003. We thank the Center for Analytic Economics and the Department of Economics at Cornell University for making this research visit possible. The current version has gained considerably from the comments made by an anonymous referee.     

Does Increased Extraction of Natural Gas Reduce Carbon Emissions?

Without an international climate agreement, extraction of more natural gas could reduce emissions of CO₂ as more clean natural gas may drive out dirty coal and oil. Using a computable equilibrium model for the Western European electricity and natural gas markets, we examine whether increased extraction of natural gas in Norway reduces global emissions of CO₂. We find that both in the short run and in the long run total emissions are reduced if the additional quantity of natural gas is used in gas power production in Norway. If instead the additional quantity is exported directly, total emissions increase both in the short run and in the long run. However, if modest CO₂-taxes are imposed, increased extraction of natural gas will reduce CO₂ emissions also when the additional natural gas is exported directed.earlier version of this paper was presented at the 25th Annual IAEE International Conference in Aberdeen June 2002.