Identifying,preventing and controlling invasive plant species using their physiological traits

A model of a plant community that is biologically reasonable and easily adaptable to economic models is presented. The model includes optimization, competition, stochastic limiting resources, and identification of redundant and invasive species. Species exhibit a rich array of traits that make them suited for some set of environmental factors and not for other sets. And because environmental factors are constantly changing, species that are very successful under one set of factors become redundant under another set, implying that an ecosystem needs redundant species as insurance. Invasive species are the flip side of redundant species as they are successful, at least under some environmental conditions. Identification depends on four physiological parameters defining each plant: two respiration parameters, a parameter that gives the plant's ideal level of the stochastic limiting resource, and the specific leaf area. The parameters are terms in an expression that gives the net energy intake of an individual plant, and the plant behaves as if it optimizes this by choosing its individual biomass. Success of species is judged based on the biomass of the species in steady state. An application extends the range management literature by incorporating the model into a rangeland manager's decision problem extends the range management literature. The model allows for multiple plant species, addresses the influence of limiting resources (other than density dependence), and tracks the response of the entire system to human and natural system perturbations. The methods allow simple predictions of community composition in the face of jointly determined economic/ecological behavior. The power of the method is demonstrated through stylized examples of alternative invasion control techniques.     

重塑城市公园开放性——“开放街区化”的理念和启示

研究公园开放的内涵区别于管理开放的研究视角， 依据城市空间密度变化和市民步行需求变化，从城市步行空间 视角，反思通过管理手段开放的收费公园在空间状态上并未真 正开放的现实问题，问题的出现在于收费管理模式引致的空间 模式滞后。以公园城市为理念指导、开放街区化为技术路径， 鉴别城市中心公园在城市步行网络中现有状态与应承角色之间 的差异。多尺度比较传统公园模式与“开放街区”尺度的不协 调性，理清传统公园空间模式向开放公园空间模式的转变途 径，提出以外部城市空间步行肌理重塑内部公园交通，构建公 园空间开放度评价体系(PSOA法)量化开放程度，以期定量描 述空间的开放状态，改善并解决空间的开放问题，更好地应对 城市中心地区的空间变化需求，服务城市步行体系，实现以人 为本的公园空间和管理的双重开放。     

私募股权投资的战略选择

随着全球次级债危机日渐严重和中国经济持续高速增长,中国作为新兴经济体所孕育的私募股权投资市场,对于全球资本正显示出越来越大的吸引力。私募基金在我国并不是新鲜事物,但由于诸多不规范操作,一直行走在灰色地带。私募基金的特性决定其具有很大发展空间,但也存在很大风险,积极探索私募股权市场的构建模式,有利于经济持续健康发展。     

Does the dutch model really exist?

The policy that led from the "Dutch disease" (in the 1980s) to the "Dutch miracle" (in the 1990s) consists of three tracks: wage moderation, retrenching public expenditure and reducing the tax burden, and slimming the welfare system. The wage moderation track seems to have been the most important. The term "Dutch model" refers to the socioeconomic system of the Netherlands. Most observers point particularly to the relatively low unemployment rate to indicate the success of this model. However, the economic inactivity rate in the Netherlands is not lower than in neighboring countries. This suggests that open unemployment in the Netherlands has been partly replaced with hidden unemployment. In particular, the disability scheme seems to contain a large component of hidden unemployment. Another feature of the Dutch model is its consensus-seeking nature, which is fostered by its institutional structure.     

从一些实际现象探讨经济与政治的关系

经济发展有其不以人们意志为转移的客观轨迹,但从实际发生的一些现象上看,政治是经济发展的开关。经济学家研究发展经济的学说,政治家则掌管实行哪些经济学说的钥匙。政治家的责任重啊!在中国,政治体制改革和经济体制改革基本上是同步的和政治体制改革落后于经济体制改革两种情况都存在。     

Testing for Long Run Purchasing Power Parity: An Examination of Korean Won

My small-scale macroeconomic model of the Taiwanese economy contains behavioral equations to explain saving, investment, the rate of economic growth, export demand, export supply, and import demand. Exploiting the two definitions of the current account (national saving ? omestic investment and export + net factor income from abroad ? imports), the in-sample dynamic simulation tracks the current account remarkably well. If the Taiwanese government pursued deliberate policies to reduce the current account surplus, this model indicates that the effects on the economy would depend critically on whether the current account surplus was eliminated by reducing national saving or by raising domestic investment. [430]     

A prototype model of the foreign exchange market of Canada: Forecasting capital flows and exchange rates

A balance-of-payments structural model of the foreign exchange market of Canada, endogenizing capital flows, the spot and forward exchange rates and the entities of the monetary sector, is developed using quarterly data for 1971–81. The capital flows have been disaggregated into ten categories and the exchange rates of the Canadian dollar have been analysed against five major currencies. While the model does not adhere strictly to purchasing power or interest rate parity, it does recognize them and it also incorporates other economic fundamentals, expectations and risk. Government interventions, although generated endogenously, are quantified implicitly and globally. The model tracks the post-Bretton Woods in-sample experience and generates ex post predictions reasonably well.     

Management strategies for tropical rain forests: Results of ecological models and requirements for ecological-economic modelling

In this study, we use two ecological forest models, namely FORMIX3 and FORREG, to analyse the impact of logging on tropical rain forests and to discuss needs for and problems of an economic extension of these models. The FORMIX3 model simulates spatial-temporal dynamics of tropical forests using an individual and process based approach. The main processes included are growth, mortality, competition, and regeneration of trees. The FORREG model simulates wood growth of tropical forests at landscape scale based on differential equations. Regeneration capabilities of logged forests are analysed and compared for different logging strategies. While conventional management strategies with a short logging cycle (here 20 years) produce low yields and cause severe changes in tree species composition, a reduced impact logging strategy with a longer cycle (here 60 years) leads to relatively high yields and causes moderate changes in species composition. Thus, longer logging cycles are preferable from an ecological point of view. However, also economic aspects influence logging decisions, thus a closer analysis of additional economic aspects of forest management is inevitable. We discuss which economic shortcomings of present rain forest models should be dealt with in the future and which additional data is needed as a consequence.     

A cost-benefit analysis of moose harvesting in Scandinavia. A stage structured modelling approach

A cost-benefit analysis of moose (Alces alces) harvesting in Scandinavia is presented within the framework of an age structured model with four categories of animals (calves, yearlings, adult females, and adult males). The paper aims to demonstrate the economic content of such a wildlife model and how this content may change under shifting economic and ecological conditions. Two different harvesting regimes are explored: landowner profit maximization, where the combined benefit of harvesting value and browsing damage is taken into account, and overall management, where the costs and damages of moose-vehicle collisions are taken into account as well. An empirical analysis of the Norwegian moose stock indicates that the present stock level is far too high compared with the overall management scenario, and that the composition of the harvest could be improved.     

城乡一体化进程中社会管理模式创新

现阶段我国总体上已进入构建城乡经济社会发展一体化的新时期,如何应对新形势和新挑战、探索适应和推动城乡发展一体化的新的社会管理模式是当前一项紧迫任务。历史告诉我们,任何一种社会管理模式,必须充分考虑当时经济社会发展的实际。现阶段的社会管理研究必须以当前的社会发展大背景为依托,清醒地分析国情,理性审视当前社会管理的背景特点,针对我国城乡一体化发展和社会转型的客观要求较为系统地提出社会管理模式创新策略。     

A collaborating inventory model in a supply chain

The present article investigates an economic order quantity/ economic production quantity model in three-layer (manufacturer, vendor and retailer) supply chain management. In each stage, the products may undergo non-conforming quality items which have less value in the market. This model maximizes a collaborating expected profit function while production rate, order quantity, number of shipments with equal sizes are decision variables and unit production cost is a function of production rate. Numerical example is illustrated to test the model.     

中国物流与经济的时空轨迹及其耦合趋势研究

采用重心模型与空间耦合模型,分析1998—2018年中国物流重心、经济和三次产业重心的时空演变,揭示其耦合规律与特征.结果表明:①物流重心总体向西南方移动,且易受外界影响变化幅度较大,变动中既存在稳定性又存在特殊时间上移动的差异性;②经济重心的轨迹呈现出先向东北,后波动式向西最后向西南移动,可见东西方向上经济的差距在缩小,南北差距慢慢扩大;③第一产业重心先向西北后折向西南移动,第二和第三产业重心移动轨迹相似,均表现出向西和向南方向移动;④空间重叠性上,与物流重心耦合性最高的产业先是第三产业,后变为第一产业,表明第一产业发展与物流的空间关联度在不断增强;空间变动一致性上,与物流重心变动一致性较强的是第二产业,说明物流与第二产业发展关系密切;物流与第三产业重心同向变动系数值较大,说明第三产业发达地区对物流吸引力较强.     

Coevolution of economic and ecological systems

This paper analyzes a model of economy–environment coevolution in which economic activities induce the genetic evolution of a biological species. This model is applied to the problem of pesticide resistance management. Just as in Munro (Environ Resour Econ, 9:429–449, 1997), we consider three main types of interactions: (1) a large pest population reduces economic revenues, (2) economic activities select for resistant genes and (3) the spread of resistant genes affects the size of the pest population. The model differs from Munro in that it includes evolutionary modeling of economic strategies. Economic agents are assumed to be boundedly rational, i.e they cannot compute the optimal level of pesticide use that minimizes resistance among pests. Economic evolution represents the change in the distribution of pesticide strategies in the population of economic agents and is modeled by a replicator dynamics equation. The interactions between economic evolution of pesticide strategies, pest population dynamics and genetic evolution of resistance of pests are studied in a system of three differential equations. We explore the dynamics and stability properties of the system using numerical simulations.     

Selection of Operation and Management Model for Industrial Mesoeconomy

Just as the regional economy and city economy, the industrial economy is the economic aggregation lying in between the macroeconomy and microeconomy. Mesoeconomic management is the extension of the macroeconomic management and has its own operation rules. The relationship between the macroeconomic and the mesoeconomic management is just like between the general department and the specialized department of the government while reflecting on the subject of the management. Establishment of the mesoeconomic management system is a model of the reform in the specialized economic departments of Chinese government.     

Health services utilization and cost utility analysis of a walking program for residential community elderly

Promoting the health and improving the ability and confidence of the elderly to live independently can reduce health care expenditures and increase the health of society as a whole. However, the evidence to promote physical activity in order to promote health among the aged population is weak, especially in regards to the economic evaluation of a walking program. These researchers confirmed that the cost utility of a 12-week walking training program is acceptable. Therefore, an outpatient clinic-based walking program for older adults is worth promoting. Cost utility analysis is the critical evaluation method in exercise programs. Health professionals are encouraged to apply the integrated indicators such as the Health Utility Index and the Incremental Cost Utility Ratio to clarify the effects of health-promotion interventions.     

斯大林的资本主义经济危机理论探析

当世界各国正从美国次贷危机引发的世界性经济危机中探索出路、找寻对策时,也在对危机的爆发缘由进行积极的思考和多种的解读,重新梳理和评价斯大林的资本主义经济危机理论,即资本主义经济危机是生产过剩的危机;资本主义经济危机是毁灭性的周期性危机;资本主义经济危机是资本主义制度的必然产物等等,这对探讨、洞析和应对当前世界性的经济危机毫无疑义具有重要理论和现实意义。     

A dynamic ecological–economic modeling approach for aquaculture management

This paper presents a Modeling Approach to Resource economics decision-maKing in EcoaquaculTure (MARKET model). The MARKET model was developed as a scenario-testing tool to provide insights on the ecological and economic interactions, which is a critical issue for sustainable aquaculture management. As a case study, the model was applied to simulate shellfish production in an embayment located in the East China Sea. A set of scenarios was used to compare the model outputs with expected trends and to test its capability to simulate relevant management scenarios. The comparison of simulated scenarios indicates that the MARKET model outputs followed the expected trends regarding both standard economic theory for consumption and production, and ecological economic theory. In all the scenarios we tested the area available for aquaculture was found to impose a limitation on production before it became less profitable to expand production. As such, in this case study, the production in the long run does not meet increasing demand. Reduction of the maximum cultivation area was simulated in one of the scenarios as an example of a conservation measure. As expected there was a reduction of the net profit of the farmers compared with the standard simulation. On the other hand, this scenario combined with an increase in price growth rate simulates a compensatory measure that led to a net profit in the same range as observed in the standard simulation. Overall the MARKET model provides insights and raises questions useful for the implementation of an ecosystem approach to aquaculture. Further developments include the simulation of waste generated by cultivated species in order to better support sustainable management objectives.     

A dynamic ecological–economic modeling approach for aquaculture management

This paper presents a Modeling Approach to Resource economics decision-maKing in EcoaquaculTure (MARKET model). The MARKET model was developed as a scenario-testing tool to provide insights on the ecological and economic interactions, which is a critical issue for sustainable aquaculture management. As a case study, the model was applied to simulate shellfish production in an embayment located in the East China Sea. A set of scenarios was used to compare the model outputs with expected trends and to test its capability to simulate relevant management scenarios. The comparison of simulated scenarios indicates that the MARKET model outputs followed the expected trends regarding both standard economic theory for consumption and production, and ecological economic theory. In all the scenarios we tested the area available for aquaculture was found to impose a limitation on production before it became less profitable to expand production. As such, in this case study, the production in the long run does not meet increasing demand. Reduction of the maximum cultivation area was simulated in one of the scenarios as an example of a conservation measure. As expected there was a reduction of the net profit of the farmers compared with the standard simulation. On the other hand, this scenario combined with an increase in price growth rate simulates a compensatory measure that led to a net profit in the same range as observed in the standard simulation. Overall the MARKET model provides insights and raises questions useful for the implementation of an ecosystem approach to aquaculture. Further developments include the simulation of waste generated by cultivated species in order to better support sustainable management objectives.