循环经济认知误区的实证分析

随着传统经济增长模式危机的出现，世界各国纷纷提出并开始建立循环经济。循环经济作为一种崭新的社会经济发展模式，人们对其认识还存在种种误区，其中认为循环经济是一种最终实现“全新的封闭式的零排放的资源利用方式”、“可解决一切环境问题”的观点最为典型。那么，是否真的存在完美的全社会物质循环呢？实现这种循环的代价是什么？本文以物质循环为基本假设条件，应用扩张环境分析用投入产出模型对社会实现全循环的可能性进行了理论探讨．并以日本为例应用该模型对日本物质循环现状和在现有条件下实现全循环的可能性及其成本进行了实证分析，论证了在现有条件下实现全社会完美的物质循环的难点。     

物流发展IGJAHP评价模型及空间格局分析--以安徽省为例

采用模糊区间层次分析法(IGJAHP),构筑物流产业发展综合评价模型,对安徽省物流发展的总体水平进行测算,并将其进程划分为恢复建设、缓慢发展、快速发展以及现代物流发展等四个阶段;在综合分析的基础上,把安徽省物流划分为皖江物流发展轴,合肥、蚌埠、阜阳物流大三角,东部外围和中西部等四大空间格局;而后,对安徽省17个地市历年物流发展水平进行评估,并计算物流发展地域差异系数,结果显示安徽省物流发展在空间上呈现地域差异扩大的趋势,在时间上经历了分散阶段和集中化阶段两个过程;然后,对安徽省物流生成量进行科学测算,分析显示其空间分布比较均匀。最后,从综合物流网络、物流信息通道、物流企业再造以及物流法规等方面提出发展对策。     

The Bank of England quarterly model of the UK economy

The Bank of England first acquired a macroeconomic model of the UK economy in early 1973, and used it for forecasting in June and July of that year. The initial model was obtained from the London Business School (LBS), but the last 14 years or so have, on the part of both the Bank and the LBS, led to developments which now make the models no closer to each other than to other large scale models of the UK. This article describes the structure and central properties of the current version of the Bank model, which has some 663 variables, 134 of which are modelled by behavioural equations, 153 by technical equations, 212 identities and 164 exogenous variables. In order to provide a transitional step between the kind of models with which most macroeconomists are familiar and the full scale version of the Bank model, one part of the article presents a very simple stylized version of the full model. This is a stepping stone to the full model which is described and analysed on a sectoral basis in Part 3, with a complete listing of equations in Part 4. Some of the simulation properties, and hence full model dynamic responses, are considered in Part 5.     

生态农业模式构建与应用——以广饶县为例

本文从农业可持续发展、资源永续利用的原则出发,探讨了构建生态农业模式的原则,以山东省广饶县为例,系统分析了在该县构建和应用生态农业模式的优势条件和制约因素,具体论述了适合广饶县发展的三种生态农业模式:农—牧—沼型、上粮下渔型和草—畜—乳型生态农业模式。     

Economic Potential of Biomass Based Fuels for Greenhouse Gas Emission Mitigation

Use of biofuels diminishes fossil fuelcombustion thereby also reducing net greenhousegas emissions. However, subsidies are neededto make agricultural biofuel productioneconomically feasible. To explore the economicpotential of biofuels in a greenhouse gasmitigation market, we incorporate data onproduction and biofuel processing for thedesignated energy crops switchgrass, hybridpoplar, and willow in an U.S. AgriculturalSector Model along with data on traditionalcrop-livestock production and processing, andafforestation of cropland. Net emissioncoefficients on all included agriculturalpractices are estimated through crop growthsimulation models or taken from the literature. Potential emission mitigation policies ormarkets are simulated via hypothetical carbonprices. At each carbon price level, theAgricultural Sector Model computes the newmarket equilibrium, revealing agriculturalcommodity prices, regionally specificproduction, input use, and welfare levels,environmental impacts, and adoption ofalternative management practices such asbiofuel production. Results indicate no rolefor biofuels below carbon prices of $40 perton of carbon equivalent. At these incentivelevels, emission reductions via reduced soiltillage and afforestation are more costefficient. For carbon prices above $70,biofuels dominate all other agriculturalmitigation strategies.     

基于生态足迹模型的可持续性度量研究--以吉林省大安市为例

针对吉林省大安市发展现状和存在的严重生态环境问题,运用生态足迹模型,采用多源数据,首次对大安市生态环境的可持续发展状况进行了定量研究;在此基础上,运用相对指标法对可持续发展的量化结果进行分级。研究表明,2001年大安市的生态需求大于生态供给,生态呈现“供不应求”的局面,人均生态赤字为0.56hm2,处于弱不可持续发展状态。     

陕西省建筑业管理模式创新研究

针对陕西省建筑业中存在的问题，站在发展的角度对其管理模式的创新提出了一些设想及相应的措施。     

Analysis of Visitor Decision Making System When Visiting Natural Recreation Sites by Multinomial Logit Model

Multinomial Logit Model has analyzed the relationship between the frequency of visits to recreation areas and the motivational factors affecting the visits. Kastro Environment Preserving Site that is located in the Black Sea coast of Marmara region in Turkey, has been chosen as the site for this study. Kastro bay is a natural park that is visited only for recreational visits. The study has been conducted on a photogenic study group due to the proximity factor of Kastro bay close to Istanbul. Kastro bay is a popular recreational park due to its characteristic advantages such as a 200 m wide and approximately 2.5 km long beach and with its high quality vegetation. The vegetation type includes ash tree, oak tree, black pine, sand lily etc. Kastro bay is also the site for the Mediterranean seals (Monachus-monachus) which are at the level of extinction. Approximately 50,000 visitors visit the region during the months of July and August. It has been concluded that there is high direct correlation between the frequency of visits and the motivational factors. It has been determined that the visits are mostly based on the sea and the ecological tourism.Jel: O13, Q20, Q26, Q51, Q56, Q57     

装备维修器材分配供应方法研究

装备维修器材的分配供应是实现对部队维修器材保障的关键一环，本文通过分析其分配供应的具体过程，对每一环节建立了切合实际、方便操作使用的数学模型，可为装备维修器材保障业务人员提供科学的决策依据，从而达到军事效益和经济效益的双赢的目的。     

Simulation driven inferences for multiply imputed longitudinal datasets*

In this article, we demonstrate by simulations that rich imputation models for incomplete longitudinal datasets produce more calibrated estimates in terms of reduced bias and higher coverage rates without duly deflating the efficiency. We argue that the use of supplementary variables that are thought to be potential causes or correlates of missingness or outcomes in the imputation process may lead to better inferential results in comparison to simpler imputation models. The liberal use of these variables is recommended as opposed to the conservative strategy.