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991.
992.
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
993.
高职烹饪工艺与营养专业人才培养研究已成为餐饮管理与服务类教学改革研究的焦点问题。本文就高职教育烹饪工艺与营养专业的定位、人才培养、教学等诸方面分析,将对专业存在的问题进行分析,提出解决的措施及教学方法改革方面的建议。 相似文献
994.
本文以探索性因子分析中统计方法的选择为目标,针对在许多应用探索性因子分析的文献中存在的统计方法选择不当致使计算结果失真这一现象,对探索性因子分析中的15种统计方法进行了比对研究,并给出了建议。 相似文献
995.
随着工作面功率的加大,矿井电压过低造成设备启动困难或不启动现象,甚至造成欠电压跳闸,因此1140V电压等级升高到3300V将是煤矿发展的前进方向。 相似文献
996.
997.
辽宁是农产品出口大省,虽然出口额呈逐年上升趋势,但近几年受国内外不同问题和因素的影响,导致辽宁农产品出口出现了瓶颈。本文在总结了辽宁农产品出口的现状的基础上,探讨了辽宁农产品出口的问题,以此总结了影响出口的因素,并基于目标满意对影响因素进行了分析,最终提出了解决措施。 相似文献
998.
Adela del-Río-Ortega Manuel Resinas Amador Durán Antonio Ruiz-Cortés 《Enterprise Information Systems》2016,10(2):159-192
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
999.
针对新疆克州塔日勒嘎水电站泄洪冲沙闸闸室置于不同强度地基基础上的情况,设计了简单易得的扩大回填方案以处理基础,通过三维有限元计算和现场的实际监测,结果表明:这种基础处理方案安全可靠,有一定的实用价值。 相似文献
1000.
In this paper, we argue that conceptually disentangling the ‘context versus composition’ aspects of regional growth is a multilevel issue. By applying multilevel models (also called random-effects models), we show (1) the importance of considering firm-specific characteristics simultaneously with region-specific characteristics, as we find that a large part of what is traditionally assigned to the impact of the region should be assigned to firm-specific characteristics and (2) that existing single-level methodologies can be problematic, as they are vulnerable to the charge of estimating significance levels that are too liberally assigned and promote exaggerations. This is illustrated empirically by showing that single-level approaches would lead to the conclusion that innovation spillovers are highly significant in a setting of Dutch urban growth differentials, while multilevel analyses shows less liberally assigned significance levels. We conclude that multilevel-effect models better fit research questions that combine firm and spatial characteristics simultaneously, especially because they allow firm-specific characteristics to be differently linked to their regional contexts. 相似文献