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951.
Special attention has been paid to sustainable macroalgae cultivation in Europe. The question on where suitable cultivation areas lie, without conflicting with current marine socio-economic activities and respecting the environment, remains a great challenge. Considering 13 criteria critical to seaweed farming such as depth, shipping traffic, and distance to ports, this paper aimed to identify suitable and sustainable offshore areas on the West Coast of Sweden for the cultivation of the Sugar Kelp, Saccharina latissima. An integrated approach with the tools geographic information systems (GIS) and multi-criteria analysis (MCA) was used to aggregate the criteria by means of Boolean and weighted linear combination (WLC) techniques. The Boolean method singled out 544?km2 as suitable, whereas the WLC method indicated 475?km2 as highly suitable. Both techniques complement each other in finding optimal sites. Furthermore, the integrated models excelled in providing an overview for effective spatial decision-making that fosters sustainable development of macroalgae cultivations within marine and coastal systems.
  • Highlights
  • To the authors’ knowledge no study on seaweed aquaculture site selection has been conducted using such a range of criteria with the purpose of including sustainability aspects within a comparative GIS-MCDA.

  • The large areas identified on the West Coast of Sweden as suitable highlight the potential of this new industry and the complexity of associated marine spatial planning.

  • Boolean and weighted linear combination methods were applied and compared, providing valuable insights in the selection of methods for spatial decision-making support. These insights should support a more sustainable development of macroalgae cultivation in the region, as well as a more resilient marine spatial planning process for blue growth strategies.

  相似文献   
952.
通过对广州南沙游艇俱乐部码头工程和海南石梅湾游艇会码头工程两个实际工程的防波堤和内护岸结构选型与设计的初步归纳和分析,提出在游艇码头结构设计中需要体现和强化游艇项目整体景观布局要求的设计理念。  相似文献   
953.
成俊霖 《路基工程》2012,(5):149-152
根据EPC工程拟建车间的场地地质、水文、气象等资料,对分段装焊车间基础对比分析了几种桩型,经过试桩和技术经济对比分析,最终选用了PHC管桩用于基础,达到经济合理,安全实用的目的。  相似文献   
954.
Public–private partnerships (PPPs) play an important role in bringing private sector competition to public monopolies in infrastructure development and service provision and in merging the resources of both public and private sectors to better serve the public needs. However, in worldwide practices, there are mixed results, substantial controversy, criticism and conflict over PPPs. This paper proposes a systematic framework for the delivery of public works and services through PPPs in general. Justified by public procurement principles, aimed at a public–private win–win solution, and based on worldwide best industrial practices and lessons from unsuccessful projects, this framework integrates the four broadly divided stages that repeat over time: (1) design of a workable concession, (2) competitive concessionaire selection, (3) financial regulation, and (4) periodic reconcession and rebidding. The four-stage framework takes into account the requirements of public services, realignment of responsibility and reward among multiple participants in PPPs, the monopolistic rights of the concessionaire, and the wide range of risks and uncertainties in the long concession period. Varying competition elements are incorporated in each of the four stages for continuous performance improvement in the delivery of public works and services. The design of the right concession forms the base on which other stages are implemented in addition to planning the project and allocating risks for enhanced efficiency. The financial regulation allows the government to address changing conditions and to regulate the concession for efficient operation with due discretion, whereas the competitive concessionaire selection and periodic reconcession and rebidding play critical roles in achieving innovation, efficiency and cost effectiveness through direct competition rather than government discretionary intervention.  相似文献   
955.
为使船舶航路选择决策能够体现决策者个体主观偏好特征,研究一种前景理论与逼近理想解(TOPSIS)相结合的决策方法.根据航路选择特征,定义航路选择决策的价值函数并构建前景价值矩阵,然后考虑船型差异,设置不同的参考点.应用TOPSIS的基本思路,通过各指标的属性值到正、负理想解的距离求出各航路选择方案相对接近度,考虑决策者对损失敏感程度的差异性,按照接近度对备选方案分别进行优劣排序.以某港口3条进出港航路方案为例进行分析,研究不同船型在不同损失敏感程度下的航路选择决策.研究结果表明,决策者不同的个体主观偏好下航路选择最优方案会呈现差异,说明决策者的主观偏好对其航路选择具有较大的影响.  相似文献   
956.
957.
程辉 《水运工程》2004,(3):40-41,48
本文探讨在高明汽车客运站的设计中,如何运用现代设计理念、材料与技术来传达新的人文精神、展现新型交通建筑的风貌。  相似文献   
958.
基于AHP的战略装车点选址群决策分析   总被引:1,自引:0,他引:1  
战略装车点选址是一项复杂的系统工程,受众多定性和定量指标的影响。为解决多决策者多目标的混合指标决策问题,提出一种实用的模糊群决策方法,通过改进的层次分析法确定各指标的权重,并结合带权欧几里德贴近度对方案加以排序,最后通过相对熵模型获得群决策结果,实例表明该方法能得到较好的应用。  相似文献   
959.
汽车用起动机的匹配与选用   总被引:1,自引:0,他引:1  
起动机作为汽车发动机上的一个重要部件,其工作特性和传动参数非常重要。本文介绍起动机与发动机、蓄电池等车辆零部件的匹配关系,并给出起动机功率的选用及计算方法。  相似文献   
960.
Building on earlier work to incorporate real option methodologies into network modeling, two models are proposed. The first is the network option design problem, which maximizes the expanded net present value of a network investment as a function of network design variables with the option to defer the committed design investment. The problem is shown to be a generalized version of the network design problem and the multi-period network design problem. A heuristic based on radial basis functions is used to solve the problem for continuous link expansion with congestion effects. The second model is a link investment deferral option set, which decomposes the network investment deferral option into individual, interacting link or project investments. This model is a project selection problem under uncertainty, where each link or project can be deferred such that the expanded net present value is maximized. The option is defined in such a way that a lower bound can be solved using an exact method based on multi-option least squares Monte Carlo simulation. Numerical tests are conducted with the classical Sioux Falls network and compared to earlier published results.  相似文献   
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