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1.
This paper proposes two novel approaches for the problem of energy management in hybrid electric vehicles. Shuffled frog-leaping algorithm (SFLA) is a recently proposed population-based optimization algorithm. This paper first formulates energy management as an optimization problem and optimizes the problem using SFLA. Then the paper makes use of SFLA as a training algorithm to train artificial neural network (ANN) and this SFLA-trained ANN is used for energy management. Interestingly, the proposed approaches of this paper are found to be robust and more efficient than contemporary approaches.  相似文献   

2.
快速工业化区域是工业化快速发展、工业化水平迅速提升、经济社会结构急剧变化的新兴地域类型。普遍存在着建设用地总量急剧扩张、空间无序分散、城乡缺乏统筹等问题。本文从佛山市南海区典型案例入手,运用新制度经济学原理。归纳和解析了快速工业化区域城乡建设用地的主要问题,认为双二元管理体制、农村土地产权不完善、城乡土地市场发育不平衡和部门规划不协调等是建设用地发展的主要体制性障碍因素,并从管理、产权、市场、规划等方面系统提出相应的制度优化对策。  相似文献   

3.
采用种植模式对县级尺度的作物进行空间配置,能够较好地解决作物空间布局中熟制比例不当、茬口不适宜等问题。种植制度空间布局优化的目的在于通过合理配置种植模式的空间位置,以充分利用并保护当地的自然资源和社会资源。其本质是一种具有自然、社会、耕作制度等多方面影响因素及空间特征的组合优化问题。传统的优化算法解决具有空间特征的组合优化问题效率很低,或者难以解决该类问题。遗传算法是一种新的智能优化算法,通过模拟自然进化过程,利用简单的编码技术和遗传操作高效地解决复杂的组合优化问题。提出了一种以GIS为平台,遗传算法为优化模型的县域种植制度空间布局优化方法。  相似文献   

4.
Manufacturing that minimises the exhaustion of natural resources, energy used and deleterious environmental impact is increasingly demanded by societies that seek to protect global environments as much as possible. To achieve this, life-cycle design (LCD) is an essential component of product design scenarios; however, LCD approaches have not been well integrated in optimal design methods that support quantitative decision-making. This study presents a method that yields quantitative solutions through optimisation analysis of a basic product design incorporating life-cycle considerations. We consider two types of optimisation approaches that have different aims, namely, (1) to reduce the use of raw materials and energy consumption and (2) to facilitate the reuse of the product or its parts when it reaches the end of its useful life. We also focus on how the optimisation results differ according to the approach used, from the viewpoint of the 3R concept (Reduce, Reuse and Recycling). Our method obtains optimum solutions by evaluating objectives fitted to each of these two optimisation approaches with respect to the product's life-cycle stages, which are manufacturing, use, maintenance, disposal, reuse and recycling. As an applied example, a simple linear robot model is presented, and Pareto optimum solutions are obtained for the multiobjective optimisation problem whose evaluated objectives are the operating accuracy of the robot and the different life-cycle costs for the two approaches. The characteristics of the evaluated objectives and design variables, as well as the effects of using material characteristics as design parameters, are also examined.  相似文献   

5.
基于遗传算法的可持续土地利用动态规划   总被引:1,自引:0,他引:1  
在建立和求解多目标可持续土地利用动态规划模型过程中,采用遗传算法并结合多目标模糊优选理论处理多目标土地利用结构优化问题。其详细步骤为:在分析区域特征基础上构建时间序列;通过现状分析设置土地利用类型决策变量,确定优化目标和约束条件,构建土地利用结构多目标优化模型;用灰色GM(1,1)预测模型对土地利用结构优化多目标模型参数进行预测;用遗传算法多目标优化方法对土地利用结构优化模型求解得pareto解集;最后运用多目标模糊优选动态规划方法对规划期内各时间段的pareto解集进行模糊动态优选,以最大优属度判定原则确定出最优决策序列。自贡市的实例表明,该方法有助于解决多目标协调问题,并通过提供多方案选择性,从而使规划更具灵活性,同时又便于充分吸纳公众参与,减少规划中的不确定性,增加规划的科学性、现实性和可操作性。  相似文献   

6.
近年来,城市热岛效应不断增强,已经成为一个突出的城市环境问题。重庆市作为长江中上游特大型城市,工业发达,经济快速发展,市区热岛效应明显,但是很少对其研究。以2007年Landsat5 TM影像为数据源,利用单窗算法对重庆市城市地表温度进行反演,并进行城市地面亮温等级划分,在从城市土地利用类型、NDVI等方面对重庆市城市热岛效应强度和空间格局分布及其特征进行了探讨。结果表明:城区热岛现象显著,且分布不均匀;不同土地利用类型对热岛效应影响不同;城市地面亮温与NDVI呈明显的线性负相关关系。最后结合重庆市的特殊地形,提出了以下解决城市热岛效应的对策:加强城市规划,调整城市结构;构建最佳绿化结构,提高城市绿化率;改变能源结构,提高能源利用率,控制工厂废气排放量。  相似文献   

7.
Regional models of land use change are evaluated as a way of identifying land use pattern based on recent quantitative and probabilistic approaches. Differentiation between models in this area is the result of the approach to the concept of land use and type of indicators used in the modeling process. Since the determination of the optima land use pattern, due to the different uses of land based on the availability of regional capabilities and spatial difference in land use, depends on an integrated model, there must be a model that can assess the existing conditions of the region and present reasonable models of land use according to regional capacities and potentials. In this research, we developed a model to present the Optimal Land Use Allocation Pattern (OLUAP) for maximizing the advantages of change and determining the methods of influencing land use change priorities. This model uses spatial models and analysis, moderates the cost-benefit function, and calculates the allocation priorities of various areas based on regional conditions. The model results show that a wide scope of Nowshahr area is allocated to natural and agricultural uses. At the same time, a limited area has been assigned to urban and industrial uses. In addition, it shows that northern strip of the region due to higher accessibility of services and infrastructures is more suited than other regions to urban and industrial areas, and these two uses have first and second priority, respectively. Besides, according to the man-made environment and the special environmental conditions, the model allocates the central lowlands and southern parts sporadically to agricultural and natural areas as first and second priorities. Since the model is spatial optimization, the suggestions of the model show the OLUAP. Therefore, one can see the optimal condition for each plot and compare it with the existing land use.  相似文献   

8.
A crucial step in complementary studies of the water quality determination is to design the additional sampling pattern or, in other words, to determine the number and location of the additional samples. Since location and number of samples highly affect decisions’ uncertainties, and because sampling process is quite costly and time-consuming, optimization of the sampling pattern will enhance the efficiency and productivity. Solution of such an optimization problem requires defining an objective function and constraints. There exist many previous studies regarding locating additional samples in other environmental problems wherein the objective function is defined as the minimization of the kriging variance (based on the problem nature), but the point is that kriging variance is not sensitive to local variability. Since manner and extent of small-scale variations are both important and necessary in water quality studies, it is required to resolve this shortcoming of the traditional objective function. Solution is to make use of the combined variance consisting of kriging and local variances. In this study, the applicability and efficiency of the minimization of combined variance as the objective function of the additional sampling was adopted and proved for a salt marsh (east of Iran) on the basis of a simulated annealing-based algorithm. It was shown, practically, that the locational distribution of additional sampling points is quite logical and more compatible with experts’ proposed methods using this objective function (compared to the traditional one).  相似文献   

9.
生态文明体制改革下围绕土地“三位一体”管理理念,强化土地利用生态管理是当今我国土地资源管理的综合思路,研究湖滨生态敏感区土地利用具有重要的生态价值和现实意义。以四川省仁寿县黑龙滩镇为实证研究区,通过构建数理量化模型和经济计量模型分析了2005~2015年间研究区湖滨土地利用状况,并差别化探讨了湖滨土地利用优化模式,提出了相关政策建议。研究表明:(1)黑龙滩镇湖滨土地利用多样化系数和均衡度在时序上变幅较小,在空间上低于全县平均水平,但总体上处于均衡状态。(2)黑龙滩镇湖滨土地利用生态安全总体为波动上升趋势,以2012年为拐点,安全状态由较安全向安全阶段转变,总体呈较安全状态。(3)黑龙滩镇湖滨土地利用生态安全主要受种植结构优化合理度、人口密度、地均牲畜量、水环境污染负荷、水土流失占比、单位耕地农药负荷的影响,其中人口密度与预期方向相反,种植结构优化合理度具有显著的正效应,其余的综合净效应为负。(4)针对黑龙滩镇湖滨土地利用变化状况以及生态安全保护需求与区域发展趋势,差别化地提出退耕还湖与持续利用生态模式、复合农业与生态种植发展模式、休闲农业与教育体验发展模式三类湖滨土地利用模式。综上提出了加强湖滨水土资源保护、优化湖滨农业结构布局和规范湖滨管理的政策建议。  相似文献   

10.
Approaches towards the management of artisanal fisheries have been enlightening the scientific literature for approximately the last 20 years. Coming from diverse disciplines such as anthropology, biology, economy, and ecology (especially human ecology), these approaches have dealt with common theory, strategies for cooperation, decision-making models, cultural contexts, and local knowledge. Fishery management depends on an understanding of the interactions between humans and aquatic resources, and in case of indigenous or of native populations, forestry resources are also considered for livelihoods. Acquiring an understanding of the local knowledge about fish and other resources, of collective local arrangements and institutions, of market interactions, and of the decision-making processes of fishers is fundamental for the management of artisanal fisheries. This review includes historical and current approaches associated with the management of artisanal fisheries. These approaches include the following: (a) cultural and human ecological approaches, including ecological models such as optimal foraging theory; (b) institutional approaches, including processes of cooperation associated with local knowledge and institutions; and (c) current ecological-economic propositions towards fishery management, such as payments for environmental services. This revision is illustrated through examples, in particular, of data collected among coastal artisanal fisheries of the SE Atlantic Forest in Brazil.  相似文献   

11.
长江流域丰富的资源、发达的经济、独特的自然特征、复杂的人地关系和严重的生态环境态势 ,决定了开展长江流域生态环境系统演变与优化调控研究 ,在国际流域科学研究和我国可持续发展研究中的重要意义。本研究的关键科学问题是 :流域生态环境系统的演化过程与退化机理及其主要驱动力 ;山—河—湖—海互动规律及其耦合关系 ;流域各子系统间的物理通量 (水、沙等 )和化学通量 (碳、氮等 )的传输和循环机理 ;流域资源和环境的承载力及流域生态安全的调控和管理等。主要研究内容包括 :流域生态环境系统演化规律及动力学 ,流域山—河—湖—海的互动规律及耦合机理 ,流域物化通量的传输过程与循环机制 ,重大生态环境问题的成因与退化生态环境的修复途径 ,流域生态环境系统的结构、功能的区划与制图 ,保障流域生态环境系统安全的优化调控与管理等。用地球系统科学的思想为指导 ,从流域整体演化角度着手 ,广泛收集各种资料 ,采取最先进的技术方法 ,强调点、线、面调查结合 ,定性与定量分析结合 ,自然演化系统与社会行为系统的结合等 ,是本项研究的主要技术途径  相似文献   

12.
Use of by-products from the steelmaking process can play an important role in achieving sustainable development. The available literature suggests that the use of iron and steel industry slags as mineral admixture or partial replacement of cement improves the microstructure of the concrete as well as its mechanical and durability characteristics. This paper reviews utilization of steel slag (SS) in the construction industry by considering current and possible future utilization fields, advantages of SS usage, and problems associated with its use. Strength and durability evolution of concretes or mortars containing SS in different ratios as aggregate or cement replacement material, combined use of ground granulated blast furnace slag with SS, and some relatively new fields of utilization of SS are also addressed. Improvements in and results of SS utilization in cement and concrete are discussed by addressing its beneficial effects. This article could help researchers to understand the recent developments in evaluation of SS in the construction industry.  相似文献   

13.
14.
《Environment international》1999,25(6-7):899-905
This study focuses on replicated exploratory optimizations of a large and difficult beef herd dynamics model, using the net present value over a 10-year planning horizon as the variable of interest. Faced with a practical search-space of the order of 10100 possible management decision combinations, the thorough but slow search pattern of simulated annealing struggled, on average falling 1.2% short of the global optimum of the system. By comparison, the cross-breeding and mutating nature of the genetic algorithm searches usually produced good results, averaging 0.1% from the global optimum. Also, these were achieved with about half the computing time used by the simulated annealing optimizations. Hence, for this problem, genetic algorithms proved the superior method.  相似文献   

15.
江苏省能源可持续发展模式初探   总被引:1,自引:0,他引:1  
针对目前江苏省能源可持续发展面临的挑战,以保障江苏能源综合供需平衡和实现能源 经济 环境协调发展为目标,以调整能源结构、优化能源供给体系、提高能源转化效率和清洁性为立足点,以充分利用省内不同区位的能源发展优势为主线,因地制宜地提炼出江苏省能源可持续发展的基本模式,包括自有资源优化开发模式和外部资源导入开发模式两大类型。其中,自有资源优化开发模式又可分为徐州煤炭工业综合体、苏北石油工业基地和沿海滩涂型可再生能源基地3种子模式;外部资源导入开发模式可分为沿江电力生产基地、苏南电力负荷中心和沿海临港型能源基地3种子模式。各种模式协同发展,有利于增强江苏省的能源可持续发展能力.  相似文献   

16.
Food production has to be increased in a sustainable way to meet the future global demand. A key position is attributed to developing countries. A deepened understanding of their agricultural regions with specific resource endowments and constraints is therefore crucial. In this study we propose a methodology based on material flux analysis (MFA) to assess the resource potentials and limitations of a Nicaraguan agricultural region. We focus on current regional and farm resource management and explore them under two scenarios. Indicators are nitrogen and the degrees of self-sufficiency (DSS) for energy, and the staples maize and beans. As data is scarce, most information is based on interviews with farmers of four categories and key persons, and on literature. The results show that nitrogen management does not differ considerably among categories. Nitrogen is mined mostly from staple plots. Self-sufficiency for beans is given in an average year. Yet, landless and small farmers neither produce enough maize for autoconsumption, nor are they self-sufficient for firewood. Energy supply is also the core problem of the region, since the DSS is 70%. Soil nitrogen stocks last at most for three more generations. Analyses with the scenario technique show that: (a) Unlimited population growth has serious consequences in the near future e.g. severe shortage of energy and food. (b) Alternative farming systems are possible, but they require reducing the population by a factor 2, and thus the creation of jobs in a Hinterland. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   

17.
Electronic and electric devices are now applied in most human activities: their diffusion is increasing worldwide; furthermore, most of them are characterized by a high replacement rate due to technological obsolescence. Consequently, environmental problems due to their diffusion are increasing; several aspects are involved from the energy consumption derived from their manufacturing processes and their use phases to their end-of-life (EOL) management. Such legislative (e.g. the European Energy Efficiency directive for household appliances) or voluntary interventions (e.g. based on the ISO standards) have been introduced for such devices: the aim is to incorporate environmental considerations in product design and manufacturing in order to benefit the environment. Some attempts are focusing on defining standardized models for the overall lifecycle including waste management. The aim of this paper is to introduce a reference model for comparing environmental product footprint of electrical and electronic equipment (EEE). All life cycles of EEE will be evaluated: a specific focus is on the EOL management process as their waste management represents a complex problem for developed and developing countries. A multi-criteria decision-making model will be developed based on the well-known analytical hierarchy process (AHP) method: differently from traditional AHP applications, an absolute model has been proposed in order to compare EEE effectively from an environmental point of view. A case study validation regarding large household appliances is proposed.  相似文献   

18.
生活能源改进是实现农村低收入家庭福利提升的关键环节之一,而资产的贫困为能源的消费造成了约束,使低收入农户难以实现能源的改进以脱离贫困现状。该文借助"贫困陷阱"的定义,将这种受制于资产贫困的能源使用困境称为能源贫困"陷阱",并从农户心理视角考察了低收入家庭更容易陷入能源贫困的原因。基于2015年中国综合社会调查(CGSS)数据,对能源贫困线进行了重新计算,认为我国现阶段农村能源贫困线应为户均600 kgce/a,并发现不论在任何能源贫困线下,收入偏低农户的能源贫困发生率、能源贫困深度和强度均远高于中高收入农户。基于此,该文同时从消费量和消费倾向两个方面估计了家庭经济状况对能源贫困的影响,结果表明:相对于中高收入农户,收入偏低农户的能源消费呈现出"既未省钱又未增效"的非经济理性特征,其能源消费负担实际更重,而消费结构却更为低效。进一步地,运用中介效应模型对这一非经济理性决策进行了解释,考察了心理因素在能源贫困"陷阱"形成中的作用,结果发现:收入偏低农户更容易表现出消极心理状态,负面的情绪和对未来的悲观预期使其在能源决策中更倾向于选择传统能源,而不愿做出能源改进的尝试。这种消极心理在一定程度上反映了收入偏低农户在能源改进中主观能动性的缺乏。正如"扶贫先扶志",政府在推行因地制宜的能源政策、开展能源基础设施建设的同时,也应该加强对贫困农户的情感帮扶,以使其产生尝试改进能源的内生动力。  相似文献   

19.
长江流域能源利用效率研究   总被引:5,自引:1,他引:4  
考察长江流域四川、重庆、湖南、湖北 、江西、安徽、浙江、江苏、上海七省二市能源利用效率,比较分析其差异以及原因,寻求提高能源利用效率的途径。首先定义能源利用效率为能源通过要素优化配置产生的技术效率,然后利用数据包络DEA和全要素效率SFA方法进行测度,最后通过比较拉氏指数与迪氏指数的优劣,采用迪氏指数法对能源利用效率影响因素进行分解。计算出七省二市及六部门1997~2006年GDP能耗、能源技术效率和能源利用效率,并分析了结构调整、技术进步和制度进化对能源效率的影响程度。研究表明:(1)结构调整是提高能源利用效率的有力措施;(2)技术进步和制度进化是提高能源利用效率的关键;(3)能源利用效率研究方法应尽量统一并不断改进.  相似文献   

20.
As the global population is expected to reach 9 billion by 2050, humanity needs to balance an ever increasing demand for food, energy and natural resources, with sustainable management of ecosystems and the vital services that they provide. The intensification of agriculture, including the use of fertilisers from finite sources, has resulted in extensive soil degradation, which has increased food production costs and CO2 emissions, threatening food security. The Bioenergy sector has significant potential to contribute to the formation of a circular economy. This paper presents the scientific, regulatory and socioeconomic barriers to the use of the nutrient waste streams from biomass thermal conversion (ash) and anaerobic digestion (digestate) as sustainable soil amendments for use in place of traditional fertilisers. It is argued that whilst the ability of combined ash and digestate to remedy many threats to ecosystems and provide a market to incentivise the renewable bio-energy schemes is promising, a step-change is required to alter perceptions of ‘waste’, from an expensive problem, to a product with environmental and economic value. This can only be achieved by well-informed interactions between scientists, regulators and end users, to improve the spread and speed of innovation with this sector.  相似文献   

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