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11.
Natural vegetation enhances the value of agricultural landscapes for people and wildlife. However, the role of anthropogenic versus topographic factors in driving the extent of natural vegetation cover within agricultural lands at large spatial scales remains unexplored. I assessed the influence of anthropogenic and topographic variables on the extent of agricultural mosaics with high natural vegetation cover in the country of Turkey where a large extent of natural and semi-natural vegetation is maintained by traditional agriculture. GIS layers depicting human land use, elevation, slope, roads and population data were obtained and summarized at two spatial scales, within provinces and for 100 km2 grid cells covering the country’s entire agricultural land area. Average farm size was also obtained at province level. Hierarchical Partitioning was conducted to determine the independent effect of anthropogenic and topographic variables on the variation in agriculture with high natural vegetation. Slope had the largest independent effect on the variation in the proportion of agricultural mosaic with high natural vegetation cover. The extent of agricultural and settlement area also explained much of the variation in natural vegetation across both grid cells and provinces. The proportion of natural vegetation increased as human population and road density decreased across grid cells and as average farm size decreased across provinces. These results suggest that while topography is the primary driver of natural vegetation cover within agricultural mosaics in Turkey, the pressures associated with urban development and agricultural industrialization may also influence the cultural and wildlife value of agricultural landscapes.  相似文献   
12.
Using tools from spectral analysis, singular and regular perturbation theory, we develop a systematic method for analytically computing the approximate price of a large class of derivative‐assets. The payoff of the derivative‐assets may be path‐dependent. In addition, the process underlying the derivatives may exhibit killing (i.e., jump to default) as well as combined local/nonlocal stochastic volatility. The nonlocal component of volatility may be multiscale, in the sense that it may be driven by one fast‐varying and one slow‐varying factor. The flexibility of our modeling framework is contrasted by the simplicity of our method. We reduce the derivative pricing problem to that of solving a single eigenvalue equation. Once the eigenvalue equation is solved, the approximate price of a derivative can be calculated formulaically. To illustrate our method, we calculate the approximate price of three derivative‐assets: a vanilla option on a defaultable stock, a path‐dependent option on a nondefaultable stock, and a bond in a short‐rate model.  相似文献   
13.
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   
14.
Process performance management (PPM) aims at measuring, monitoring and analysing the performance of business processes (BPs), in order to check the achievement of strategic and operational goals and to support decision-making for their optimisation. PPM is based on process performance indicators (PPIs), so having an appropriate definition of them is crucial. One of the main problems of PPIs definition is to express them in an unambiguous, complete, understandable, traceable and verifiable manner. In practice, PPIs are defined informally – usually in ad hoc, natural language, with its well-known problems – or they are defined from an implementation perspective, hardly understandable to non-technical people. In order to solve this problem, in this article we propose a novel approach to improve the definition of PPIs using templates and linguistic patterns. This approach promotes reuse, reduces both ambiguities and missing information, is understandable to all stakeholders and maintains traceability with the process model. Furthermore, it enables the automated processing of PPI definitions by its straightforward translation into the PPINOT metamodel, allowing the gathering of the required information for their computation as well as the analysis of the relationships between them and with BP elements.  相似文献   
15.
高等教育工作努力的方向应以探索教育的发展规律、发展思路、突出学校特色优势为重点内容。人民满意的教育说到底就是在多元质量观照下的适需教育,这要求高等教育管理实践中应强调“去行政化”管理方式、发展“生态文化”的价值定位及“内涵式发展”道路。同时,既要遵循“有所为有所不为”的教育发展思路,又要处理好满足需要与开发潜能、人才培养模式与求真务实之间的关系。  相似文献   
16.
This study aims to investigate consumer perceptions and reactions in terms of specific discount patterns (fixed price, 40% discount, discount from 500 TL to 300 TL and 20% + 25% discount) in price promotion. According to the results, specific discount patterns in price promotion have a significant effect on perceived price attractiveness and purchase intention. When the specific discount patterns in price promotion and gender interaction were analyzed in terms of perceived price attractiveness, the scenario of the “discount from TL 500 to TL 300” significantly differentiated from both the control scenario (fixed price) and experimental scenarios for female. For males, no significant difference was found between the control and experimental scenarios. In terms of purchase intention, a significant difference was found between the fixed price scenario and the discount scenario from 500 TL to 300 TL and between the fixed price and 20% + 25% discount scenario. The theoretical managerial implications of the study were discussed, and future research suggestions were presented.  相似文献   
17.
In this paper, I study the causal effects of part‐time work on current and future wages. To estimate these effects, I use a random effects model with a wage equation capturing the employment history and a dynamic multinomial probit component for the choice of employment status. Exclusion restrictions from the institutional context are exploited to support identification. The results suggest that working part‐time with few hours has a large causal effect on current wages, but more extensive part‐time work does not reduce current wages. However, both types of part‐time work lead to negative long‐term wage effects.  相似文献   
18.
The relationship between local development patterns and highway networks is complicated, as suggested by studies using various analytical methods. The spatial effects of each hierarchical highway network on local development patterns remains unclear. This study combines space syntax and the hierarchical linear model (HLM) within the research framework in a case study of Taiwan. The former is employed to model the topological accessibility of multilevel highway networks, and the latter is applied to handle the hierarchical relationship between multilevel highway networks and local development patterns. Results indicate a high R-squared (R2 = 0.803) value, and statistically significant cross-level interactions are observed. The results show the different spatial effects of various highway networks on the scale of local development patterns, and confirm consideration of highway networks with classification in the research design. The implications of the findings may be appropriate for substantive planning and future research approaches.  相似文献   
19.
This exploratory study analyzes the careers of 307 supply chain executives (SCEs). Motivated by career theory, our findings create new knowledge about the educational backgrounds and career paths that lead to SCE positions. Based on an optimal matching analysis, we are able to distinguish among six career patterns for SCEs. They differ in terms of the individuals’ previous professional experience, educational background, and the time they needed to arrive in an executive position. By characterizing the backgrounds and career paths of SCEs, we show that supply chain management (SCM) is truly a cross‐functional profession. Our findings suggest that previous staff responsibility appears to be a more important hiring criterion than extensive SCM experience. While 56% of the executives had prior staff responsibility, only 12% of the cumulated careers were actually spent inside the SCM function.  相似文献   
20.
A new kernel-type estimator for the distortion risk premiums of heavy-tailed losses is introduced. Using a least-squares approach, a bias-reduced version of this estimator is proposed. Under suitable assumptions, the asymptotic normality of the given estimators is established. A small simulation study, to illustrate the performance of our method, is carried out.  相似文献   
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