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51.
模糊决策在房地产建筑方案优选中应用   总被引:5,自引:0,他引:5  
在房地产开发中建筑方案的决策是一项综合性、专业性、技术性极强的工作。针对以往建筑方案评价的缺陷,归纳总结了,影响方案评价的基本因素,运用模糊决策理论和结合层次分析法,探讨了方案决策的问题,并对实例进行分析。  相似文献   
52.
We study whether pension fund managers, as professionals of important social and financial products, are able to add value for their clients and adapt to economic changes. To this end, we analyze the performance and skills (market timing and stock picking) over the economic cycle from both pension fund and manager perspectives. This double analysis allows examining whether skills reside in managers and/or funds and control for manager substitutions. Despite the long-term nature of pension funds, we find that both fund and manager skills vary with market conditions, showing better evidence of stock-picking in booms, and of market timing in recessions. Nonetheless, top (bottom) funds and managers exhibit both (incorrect) skills in booms and in recessions. Some of the top (bottom) funds and managers are the best (worst) in both abilities in the same periods, but not in different periods, showing that not all managers have the ability to adapt to market conditions. Additionally, managers with limited skills tend to specialize because diversification requires multi-task skills and the non-specialization of these managers usually results in incorrect skills.  相似文献   
53.
Land exploitation, as an important strategy to mitigate farmland loss and stabilize grain production, has been adopted to compensate farmland loss due to rapid urbanization in China. Bounded by the limited capacity and obvious spatial variations of national farmland reserves, it is essential to arrange land exploitation activities timely and reasonably. In this study, we propose an indicator for the status of regional land exploitation, the Exploitation Degree, to facilitate an overview of land exploitation programs in China at both provincial and prefectural levels based on project data from 2006 to 2012. To further our understanding of the regional features of land exploitation activities, we employ the Lasso model to identify and quantitatively assess influencing factors on land exploitation. Our study shows that: (1) contemporary land exploitation practices in China are significantly inconsistent across exploitable farmland reserves. Some areas are greatly over-exploited and such irrational land exploitation has been persistent; (2) related national land plans designed to guide land exploitation efforts centered on resource-rich regions and critical areas do not function as intended. Therefore, we suggest that China⿿s land exploitation policy shall be improved by reconsidering the orientation of land exploitation policy, coordinating land exploitation activities with productivity improvements and eco-system protection, and enhancing the power and scope of the plans in controlling and guiding land resource management.  相似文献   
54.
In the past few decades, urbanisation has become a major phenomenon in European cities, thus representing one of the key human land cover changes with socio-economic and environmental impacts. In the Lisbon metropolitan region it is estimated that 17% of natural and farmland have been transformed into artificial areas. Since the end of 1990s, specific EU guidelines have been issued to contain urban sprawl and preserve agricultural land. Spatial planning in Portugal obviously is integrating these assumptions into the statutory land-use master plans. But what is the performance of this land use planning system regarding land cover evolution itself? Based on the Lisbon metropolitan region (LMR), one of the major areas of urban growth in Portugal, we examine spatio-temporal land cover patterns between 1990 and 2007 by integrating cross-matrix analysis, spatial metrics, and gradient analysis. Additionally, we overlay these land cover dynamics with municipal master plans that regulate land development in order to assess the compliance levels of this land-use regulatory system. Results indicate that: artificial areas are growing by coalescence and/or by scattered development along an urban–rural gradient; agricultural land is reducing and fragmentation is increasing to enlarge peri-urban spaces; there are high levels of conversion of agricultural land into urban land in protected areas, thus showing a lack of compliance to the land use regulatory system visible in the existing gaps between the original land-use assignments of the master plan and the actual developments.  相似文献   
55.
We examine the effects of a Finnish pension reform on firms' incentives to hire older employees. The reform restricted the eligibility ages for early retirement and changed the size‐related contribution rates of firms. According to our theoretical model, the positive effect on the values of new hires extends to age groups younger than those directly affected by the reform, and the effects are strongest in the largest firms. These model predictions were confirmed in a difference‐in‐difference‐in‐differences analysis on the probability of the hiring of workers of different ages in firms of different sizes.  相似文献   
56.
In this paper, we propose a goal-based investment model that is suitable for personalized wealth management. The model only requires a few intuitive inputs such as size of wealth, investment amount, and consumption goals from individual investors. In particular, a priority level can be assigned to each consumption goal and the model provides a holistic solution based on a sequential approach starting with the highest priority. This allows strict prioritization by maximizing the probability of achieving higher priority goals that are not affected by goals with lower priorities. Furthermore, the proposed model is formulated as a linear program that efficiently finds the optimal financial plan. With its simplicity, flexibility, and computational efficiency, the proposed goal-based investment model provides a new framework for automated investment management services.  相似文献   
57.
供给侧结构性改革作为适应和引领经济发展新常态的重大创新,用改革的办法对错配的供需结构和扭曲的要素配置进行矫正,根据需求结构变化及时优化供给结构,实现资源优化配置和经济长期均衡发展。阳江作为滨海旅游城市,应抓住机遇,深化养老旅游产业供给侧结构性改革,优化养老旅游产业的供给结构,合理配置养老旅游资源,扩大养老旅游服务的有效供给,推进养老旅游产业的持续健康发展。  相似文献   
58.
This research aims to analyze cooking parameters in liquefied petroleum gas (LPG), electric resistance and induction stoves for eight dishes of the Ecuadorian cuisine. During tests, it has been monitored the temperature, time, electrical grid parameters, concentrations of CO and CO2. In addition it has been studied the microbiological and physiochemical changes produced by the thermal treatment in food and a discriminative triangular test for determining the differences in the consumers perception between samples made with induction and LPG based stoves. The results showed which even with an exhaust hood working, there was still a significant value of concentration of CO and CO2 during cooking with a LPG stoves. As a result of these analyses the induction stove shows a better response during the heating process and energy efficiency which have influence in temperatures, taste, vitamin preservation, cooking times, energy consumption and cost to the user.  相似文献   
59.
We develop and test a new approach to assess defined benefit (DB) pension plan solvency risk in the presence of extreme market movements. Our method captures both the ‘fat-tailed’ nature of asset returns and their correlation with discount rate changes. We show that the standard assumption of constant discount rates leads to dramatic underestimation of future projections of pension plan solvency risk. Failing to incorporate leptokurtosis into asset returns also leads to downward biased estimates of risk, but this is less pronounced than the time-varying discount rate effect. Further modifying the model to capture the correlation between asset returns and the discount rate provides additional improvements in the projection of future pension plan solvency. This reduces the perceived future risk of underfunding because of the negative correlation between interest rate changes and asset returns. These results have important implications for those with responsibility for balancing risk against expected return when seeking to improve the current poor funding positions of DB pension schemes.  相似文献   
60.
Ricky Kanabar 《Applied economics》2016,48(58):5699-5716
The UK state pension (which depends only on age) includes an option to defer take up which yields either a subsequent lump sum or higher weekly pension. We analyse the joint decisions on pension deferral and intertemporal labour supply/participation in a lifecycle setting. We show that deferral is purely a financial decision, but the impact of deferral on work decisions depends on preferences, wage rates, non-labour income and initial wealth. To exactly characterize this, we use a quasilinear utility function and provide calibrated simulations. We also discuss the choice between a lump sum or increased weekly pension.  相似文献   
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