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1.
Systematic approach to the maintenance of rural road network is a very important issue from the viewpoint of public costs. Most countries developed custom PMS (pavement management systems) based on deterministic or probabilistic approach. The main goal is to ensure safety and continuity of road traffic on road network with low intensity and lower technical requirements. Article presents PMS used for Slovakia rural road network based on road construction diagnostics, traffic volume, climate factors and evaluation of maintenance works economics effectives by using of software tools like HDM-4 developed by World Bank. Local road administrators of rural road networks often lack the software equipment, most PMS, however effective, are often cumbersome, demanding in regard to energy, know-how and software equipment. The majority of local road administrators of rural road networks thus resort to non-effective reactive maintenance strategies. This article describes an easy to use method, based on predetermined maintenance repair and rehabilitation standards. A simple method, based on road user cost, is introduced that administrator can use to prepare a list of road section eligible for repair according to their repair priority.  相似文献   

2.
基于CiteSpace的国内乡村植物景观研究   总被引:1,自引:0,他引:1  
卢周奇  邱冰 《园林》2021,(2):80-87
乡村旅游业正以前所未有的速度飞速发展,乡村植物景观作为一种展示乡村风貌的景观开始逐渐进入研究者视野。文章以中国知网(CNKI)2000-2020年收录的期刊和学位论文为分析对象,借助于CiteSpace软件,量化解析出"植物景观设计""植物群落""植物配置""农村生活污水"等研究热点,归纳出乡村植物景观设计方法、乡村植物应用分析调查、乡村植物与污水净化、乡村植物物种多样性、乡村植物景观评价和乡村植物保护6个主要研究方向。结合当前乡村振兴的实践需求,提出尚待加强的3个研究方向,即乡土植物资源的挖掘和栽培、乡村特色植物景观营造模式和基于乡村风貌保护的植物种植模式。  相似文献   

3.
单一城市化模式导致城郊地区价值流失严重,城乡空间发展呈现简单趋同和无序蔓延趋势。“重形态、轻产业”是这一问题产生的主要原因。根据对国内外城郊产业与空间发展的相关研究分析可知,农业多功能发展有助于实现城郊最优价值。本文在对郑州城乡结合部大量研究的基础上,分析了郑州城郊农业发展的竞争优势及不足,揭示出“经济、生态、社会”农业多元价值观下农业产业集群是郑州城郊农业发展趋势;并探讨了捉业集群引导下城乡结合部空间优化策略,通过构建具有多功能的产业空间体系,形成城乡良性增长边界,最终实现有差别的城乡一体化发展。  相似文献   

4.
城乡结合部处于城市与乡村交界地带,是一个充满生机、矛盾和困惑的区域。1980年代以来我国城乡结合部进入快速扩张与发展时期,其发展演化历程折射出经济、社会、制度的种种变迁与烙印。长期以来,城乡结合部处于混乱状态,发展过程中存在的种种问题备受关注。经济利益驱动下城乡结合部的农副产品供应、生态保障与城市边界增长约束功能逐渐丧失,在被动、盲目的发展状态下日渐形成了独特的经济社会空间体系,且结构、效率与各种利益关系趋于恶化。城乡结合部特殊的经济地理区位和所处的发展阶段,传统的城镇化模式及对此区域的低价值判断和机会主义思想等共同作用,使其发展陷入困境。城乡结合部为城市与区域发展做出了突出贡献的同时也为其高端化发展带来障碍。今后,必须突出城乡结合部自身的功能,统筹规划、适度发展,并创新治理与改造模式。  相似文献   

5.
The goal of this study is to determine specific guidelines for Iraqi architects to contribute to the design and composition of energy-efficient housing units within the limits of a normal budget, locally available materials and technologies. These units can provide comfort despite the current energy situation in Iraq. The study is based on a computer simulation for a reference building in Baghdad, which has been selected according to the urban conditions, building legislations, housing market and statistics. The final results displayed the main recommendations and the possibility to achieve up to 50% energy reduction with a pay-back period not exceeding two years in some cases. There are some measures that have big energy saving potential. Yet, some of the measures may require big investment or have some bad environmental impacts. Some other good measures are already being implemented.  相似文献   

6.
Commonly proposed concepts, like KBS-3V, for disposal of highly radioactive waste imply construction at medium depth (400-600 m) in granitic rock, which is excellent for constructing a stable repository. VDH (very deep boreholes) represent an altemative concept with the advantage that the rock is much less permeable and that the very salt, heavy groundwater is stagnant. Both require engineered barriers in the form of canisters and waste-embedding clay but for somewhat different purposes. Canisters are the most important waste-isolating barriers for KBS-3V but are less important for VDH. The waste-embedding clay is needed for preserving the KBS-3V canisters by being tight and ductile, but plays a minor role for the VDH. The backfilled deposition tunnels in a KBS-3V repository provide very limited hindrance of radionuclides to move to the biosphere while the clay seals of VDH effectively prevent possibly released radionuclides to reach up to the biosphere. Comparison of the KBS-3V and VDH concepts indicates that the last mentioned one has several advantages but that certain issues remain to be worked on for becoming a number one candidate.  相似文献   

7.
If Europe is to achieve the planned transition to a low carbon economy by 2050, succeeding in improving the energy efficiency of the largely inefficient existing building stock will be pivotal. Certain energy efficiency retrofitting obligations have now emerged as part of the EU's Energy Performance in Buildings Directive and the Energy Efficiency Directive. Challenges for retrofitting currently include gaps in technical skills both amongst building trades and professionals, a lack of awareness of building owners and users, concerns about compromising cultural heritage as well as a lack of viable business models, comparatively high cost and resulting long pay-back periods currently hamper the progress. Lessons can be drawn here form the EU-funded initiative CONCERTO, which helped 58 communities in 23 countries to reduce their dependence on conventional energy supply by implementing energy efficiency measures and integrating renewable energy sources not at single building scale but community scale. Almost all of these entailed retrofitting activities bad to find solutions to the issues mentioned. This paper presents a selection of conclusions regarding retrofitting to be drawn from the analysis undertaken under the project CONCERTO premium, which analysed outcomes across the 58 projects on behalf of the European Commission and focuses in particular on the political relevance of outcomes.  相似文献   

8.
Up to now, reuse and recycling of existing buildings have not been examined widely. This paper discusses the theories, methods and practicalities of buildings' end of life with a main focus on planning and managing reuse and recycling of existing buildings. Our aim is the realistic modelling of theoretical scenarios for end of life based on a case study. The methods of building survey, material classification and documentation for reuse, recycling and disposal of existing constructions are presented. Investigations and calculations were done on an existing cottage in the Alps. The ecologically most beneficial disposal phase of the old wooden hut is our main objective. Critical questions arise from the quality of the material and how it can be extracted, separated and balanced in an appropriate way. A systematic survey of the building by inspection of constructions and materials in iterative steps allows a detailed material balance with condition and property information. This information is crucial for scenarios and material flow analysis of demolished and rebuilt building in environmental system analysis. For future planning, the reuse and recycling of existing buildings should be integrated quite early in the planning process so that we can use the materials in the best way.  相似文献   

9.
Teaching design incorporating a sense of sustainability to architecture students is a challenge today, primarily because of the trend to label every design as sustainable or green even though it is no different from a more traditional one. The result is a "green-washed" education in architecture. To address this issue, this paper describes a teaching methodology of architectural design with a special focus on sustainability implemented in the Graduate School of Architecture in Clemson. This method includes an analysis of the location, the climate conditions, the materials needed and the construction process. Knowing that sustainable design is generally perceived as being expensive, there is a special focus on simplicity and affordability. Rather than relying on expensive technical solutions, students are encouraged to design for the given environment and apply passive strategies. In the approach discussed in this paper, the design process is a number of logical scientific decisions rather than an intuitive draft. The goal of this pedagogy is to raise awareness about how to handle global resources carefully and to show the importance of the later performance of the project as a key to design. The teaching strategy is described here along with the successful participation by our graduate students in a number of refereed competitions.  相似文献   

10.
Energy is one of the most important resources in the economy of developing countries. Jordan depends mainly on imported oil and gas at international prices. This creates a heavy burden upon Jordanian national economy, which is reflected in the same time on other sectors of the Jordanian society. The ever increasing fuel prices make it very necessary to look for new renewable energy resources. Jordan as a developing country with its fast growing urban development and construction projects will be studied. It is worthy to study the dynamic relationship between end user, fuel and comfort in the residential sector. Energy is a chronic problem in Jordan, due to lack of non renewable energy resources, the end consumer is influenced by this fact, in achieving his basic energy needs. This study tries to shed light on the fuel poverty line, definitions and parameters of fuel poverty. And to study what has been done in this regard on both international and local level. No studies have been identified in Jordan which, explore the problem of fuel poverty, especially after the vast and recent increase in fuel prices internationally and locally. This study will follow theoretical and field survey to understand the relationship between comfort, energy and building fabric. Method will depend mainly on field survey and statistical data, and necessary measurements, questionnaires will be adopted when necessary to explore comfort levels related to fuel consumption. Summary and recommendations will be concerned with how thermal comfort could be achieved within the ranges of fuel accessibility, building fabric, minimum pollution and cost.  相似文献   

11.
Combination of a bus system and cable car system can reduce the overall congestion of traffic in urban areas, where surrounding hills or mountains hold larger settlements or tourist and recreational infrastructure. With this kind of integration number of individual car trips can be significantly reduced. In this paper, the authors present an analysis of the pilot project implementation, which was held in Maribor. The authors conducted a limited test trial of two means of transportation, combining them into a single operating transport offer for inhabitants and tourists. Combined transport option proved to be a good starting point for reduction of traffic and parking congestion during winter tourist season and beyond. Method used in the research, in order to gain actual potential of integrating two systems and improving public transport offer, was establishment and implementation of the pilot project in Maribor during January 2011. Data was gathered through interviews of two interest groups. The first covered the users who were brought to the foothills of Pohorje's ski center by bus. The second covered the cable car users that were traveling to the top of Pohorje. For a limited time period, a trial principle of a single ticket was established, which gave ski-pass holders free bus ride on bus line No. 6. With the aim of reducing CO2, test drives of hybrid bus and compressed natural gas bus were conducted alongside many promotional activities with which users were informed of importance of environmentally friendly mobility options.  相似文献   

12.
The urban condition of the European territory requires new approaches to explain the current development of cities and to propose new planning tools. The aim of this paper is to demonstrate that we can support an innovative perspective based on intermediate geographical scales, more useful for outlining the specific features of territory. While we analyze the territory, we should overcome the strictly local scale of the administrative boundaries and create new relationship between contemporary urban concepts (metropolization of territory and metapolis) and the regional ecological patterns. In the case of Valladolid (E) urban/metropolitan area, we focus on both causes and process of city growth. We have understood that it could be inefficient for planning forgetting the real spatial configuration (the city is located in an intersection between two territorial corridors) and misunderstanding the territorial role of the city at different scales (the double centrality in the emerging urban area and in the region). The significance of this case is to reveal the inter-scalar condition of places as generators of constraints in the contemporary urban fabric and, at the same time, to show the quality and the potential of places in the future urban realm.  相似文献   

13.
The present paper represents comparison of continuum shells and latticed shells with qualitative analysis. For shells, the mechanical characteristics in the two perpendicular directions are continuous and related to each other, and any change in thickness will result in change in stiffness in any direction. In latticed shells, members are discrete and stiffnesses in two mutually perpendicular directions are discontinuous and independent of each other. Therefore, sensitivity of geometrical imperfection for buckling of latticed shells should be different from that of continuum shells. The author proposes a shape optimization method for maximum buckling load of a latticed shell. A single layer latticed dome is taken as a numerical example, and the results show that the buckling load parameter for full area loading case increases 32.75% compared to that of its initial shape. Furthermore, the numerical example demonstrates that an optimum latticed shell with maximum buckling load, unlike an optimum continuum shell, may not be sensitive to its geometrical imperfection.  相似文献   

14.
In post-disaster emergency shelter aid, various relief agencies and other actors with different backgrounds need to cooperate in a tremendously short amount of time and under very different circumstances. In this article, we describe a research project that develops and tests a new approach in which the demands for shelters in a specific situation are methodically connected with available, innovative and sustainable shelter solutions, a DSS (decision support system). The DSS is a digital tool that translates the gathered evidence on needs, solutions and location including long-term effects of shelter provision into advice for the provision of sustainable, integral broader shelter solutions and designs. The outcome is a set of characteristics for a DSS for the provision of on-demand emergency shelters. A DSS that meets these characteristics leads to the provision of sustainable shelters that meet the needs of the users and, therefore, have higher performance in long term.  相似文献   

15.
In the United States, university buildings use 17% of total non-residential building energy per year. According to the NREL (National Renewable Energy Laboratory), the average lifecycle of a building in a university is 42 years with an EUI (energy use intensity) of 23 kWh/m^2/y. Current building and energy codes limit the EUI to 16 kWh/m^2/y for new school buildings; this benchmark can vary depending on climate, occupancy, and other contextual factors. Although the LEED (leadership in energy and environmental design) system provides a set of guidelines to rate sustainable buildings, studies have shown that 28%-35% of the educational LEED-rated buildings use more energy than their conventional counterparts. This paper examines the issues specific to a LEED-rated design addition to an existing university building. The forum, a lecture hall expansion of to an existing building at the University of Kansas, has been proposed as environmentally friendly and energy-efficient building addition. Comfort and health aspects have been considered in the design in order to obtain LEED platinum certificate. The forum's energy performance strategies include a double-skin facade to reduce energy consumption and PV (photovoltaic) panels to generate onsite energy. This study considers various scenarios to meet NZEB (net-zero energy building) criteria and maximize energy savings. The feasibility of NZE criteria is evaluated for: (a) seasonal comparison; (b) facility occupancy; (c) PV panels' addition in relation to double skin facade. The results of NZEB approach are compared to LEED platinum requirements, based on Rol (return on investment) and PV panel's efficiency for this specific educational building.  相似文献   

16.
Crushed fine aggregates are widely used for full or partial replacement of natural sands in concretes. The crushed sands present different characteristics from the natural sand, especially if taking into account the content of microfine particle, the distribution of particle sizes, the shape features, besides the different lithological origin. From the rheological point of view, the crushed sands frequently provide mixtures with high yield stress, high viscosity, high cohesion and internal friction, which hinders its use in concrete. This study is focused on the evaluation of the rheological behavior of concrete mortar phase when using different lithological types of crushed sand in total replacement of natural sand. The lithological types surveyed were granite, calcitic limestone, dolomite limestone and mica schist. Each of these sand types was studied in two ways: in natura and with adjusted grading curve. The results show the best performance of calcitic limestone providing lower viscosities and lower yield stress in mortars.  相似文献   

17.
This article aims to assess the spatial distribution of the IST (internal surface temperatures) in the ceiling and DBT (dry bulb temperatures) of a LGR (light green roof) in a test cell. Cover systems known as green roofs have the potential to retain rainwater and help reduce runoff. However, the characteristic considered in this work is the insulation capacity of this kind of coverage. To evaluate the spatial distribution of temperatures in an environment with light green roof, we proposed a new method for acquisition of series of climatological data and temperatures according to spatial and temporal approaches of dynamic climatology. Climatological data were provided by an automatic weather station and temperatures were collected in a test cell with light green roof. The spatial distribution of surface temperatures and internal air temperature (DBT) are based on the concepts of a climatic episode and typical experimental day from the study of the dynamic climatology. The results led to the conclusion that the light green roof has a balanced spatial distribution of the IST and of the internal air temperature (DBT), i.e., without substantial variations over the day. The new methodology also showed the importance of specifying the location of the sensors and automatic weather station in experimental studies on the thermal behaviour of buildings.  相似文献   

18.
The aim of this paper is to present the urban history of Juiz de Fora, a city with some 500,000 inhabitants in southeastern Brazil, and discuss how strategic decisions about the planning and construction of roads and highways can determine ways of life in a city. While paths may integrate landholdings and territories, they may also segregate communities and environments, causing deep rifts in the fabric of urban and land areas. The growth of Juiz de Fora is particularly marked by the construction of paths. This article reviews the local urban history from the establishment of paths in the city, to an analysis of the major impact and benefits they have had, notably on the local economy and demographics, as well as on the conservation of the local environment: Issues that are frequently relegated to a secondary role in the cost-benefit analysis of the city's planning decisions. After analysis of the case study, the authors concluded that citizens should be included on the agenda of the city, from spectators to actors of daily urban life.  相似文献   

19.
20.
The theory of constraints thinking process, created by Israeli physicist Eliyahu M. Goldratt, has emerged as a tool for achieving competitive advantage. Many researches also focused on the application of lean thinking developed by Toyota and proposed by Ohno. This philosophy has been proven to be effective in several production processes. This paper aims to propose a method of problem solving through the integration of theory of constraints thinking process and the principles of lean production. As a tool for problem identification, the method defends the use of current reality tree and, to solve problems, the lean thinking tools, proposed by Picchi. The developed method was implemented in a contractor. The research methodology was research-action. Among the results, there was a realistic diagnosis about the core problems in company. According to this, the core problem of the contractor is “the lack of commitment of manpower” that results in the main problem “the financial loss”. The principle of perfection was verbalized as a proposal to solve the problems and the tools to be implemented for solving problems were “commitment of senior management to employees” and “simplicity in communication”.  相似文献   

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