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1.
以上海迪士尼1.5期为例,阐述BIM(Building Information Modeling)技术在园林工程中的运用流程、建模策略、模型精度需求以及在实际施工中的运用优劣势。根据1.5期园林BIM模型的建模经验,总结出不同园林要素的BIM建模策略。以实际的园林施工需求为标准,对这些园林要素的BIM模型精度需求进行讨论。研究BIM技术的直观化特性和数据化特性为园林工程带来的构造性优势、综合性优势、避让性优势、快速查询优势和工程量核算优势,进而探讨这些BIM技术优势为园林工程带来的积极意义。  相似文献   
2.
许若男 《价值工程》2021,40(2):97-99
随着我国经济的快速发展和“走出去”、“一带一路”倡议的实施,越来越多的企业在政府的带动下开始进军国际市场,但是国际工程往往施工周期长、金额较大、技术复杂、政府干预较多、不确定性因素多,风险与机遇并存,针对2020年全球新冠病毒蔓延这一特殊的时期,企业更应在投标阶段做好风险分析、测算、管控工作,合理规避风险,总结经验教训,保证企业履约能力和竞争性。  相似文献   
3.
为实现工程造价精细化管理目标,需要各个环节的相互配合来达到资源优化配置。BIM技术依托虚拟建模技术,实现了对工程项目的数字化建造管理。实践证明,将BIM技术融入项目工程造价管理体系中,有助于提升工程造价管理的整体质量。论文立足工程造价精细化管理的内涵,剖析了BIM技术在工程造价精细化管理中的应用价值,并提出了BIM技术在工程造价精细化管理中的具体应用策略。  相似文献   
4.
郭伟  柴喜洲  刘琪 《价值工程》2021,40(3):129-131
糯扎渡水电站坝后量水堰在运行过程中为强化量水堰功能,截断坝基渗透水流,实施量水堰防渗工程,形成整体的枢纽工程防渗帷幕体系。本文通过对量水堰防渗工程施工关键技术的总结,介绍了在防渗标准高、施工难度大、工期紧的情况下高效高质完成防渗工程的具体施工方法,可为今后类似水利水电工程施工提供经验和借鉴。  相似文献   
5.
随着城镇化进程的加快和城市经济辐射能力的增强,以特大城市中心城为核心的都市圈逐渐形成,都市圈内的经济联系更加紧密,都市圈核心区与外围的出行需求迅速增长,市域(郊)铁路的概念被引进,选择符合市域(郊)铁路特点的车辆类型是设计的重点。  相似文献   
6.
This study proposes an integrated simulation approach, which consists of a microscopic traffic simulation model, a vehicle dynamics model, and an emission estimation model, in order to estimate emissions based on more reliable vehicle performance measures. The vehicle performance measures such as engine power and engine speed significantly relate to the amount of emissions, and road curvatures and inclinations are the core inputs affecting these vehicle performance measures. Therefore, providing reliable vehicle performance measures reflecting the road geometric attributes is critical for a reliable emission estimation. This study proposes to use the microscopic traffic simulation model for generating vehicle trajectories, which is advantageous in modeling various traffic situations, and the vehicle dynamics model for producing the vehicle performance measures based on the vehicle trajectories. Finally, the outputs from the vehicle dynamics model are fed into the emission estimation model to compute emission measures. This study conducted a case-study using two road sections, one is a hypothesized road section, including various curvatures and inclinations with regular variations, and the other is a Kesselberg road section, which is an actual geometry in Bayern, Germany. The emission measures are estimated in these case-study road sections using both an existing simulation approach and the proposed integrated simulation approach. The difference between these two emission estimation approaches is discussed in terms of the emission measures, including fuel consumption, nitrogen oxides, and particulate matters.  相似文献   
7.
A separation between the academic subjects statistics and mathematical statistics has existed in Sweden almost as long as there have been statistics professors. The same distinction has not been maintained in other countries. Why has it been kept for so long in Sweden, and what consequences may it have had? In May 2015, it was 100 years since Mathematical Statistics was formally established as an academic discipline at a Swedish university where Statistics had existed since the turn of the century. We give an account of the debate in Lund and elsewhere about this division during the first decades after 1900 and present two of its leading personalities. The Lund University astronomer (and mathematical statistician) C. V. L. Charlier was a leading proponent for a position in mathematical statistics at the university. Charlier's adversary in the debate was Pontus Fahlbeck, professor in political science and statistics, who reserved the word statistics for ‘statistics as a social science’. Charlier not only secured the first academic position in Sweden in mathematical statistics for his former PhD student Sven Wicksell but also demonstrated that a mathematical statistician can be influential in matters of state, finance as well as in different natural sciences. Fahlbeck saw mathematical statistics as a set of tools that sometimes could be useful in his brand of statistics. After a summary of the organisational, educational and scientific growth of the statistical sciences in Sweden that has taken place during the last 50 years, we discuss what effects the Charlier–Fahlbeck divergence might have had on this development.  相似文献   
8.
Two decades ago, the rules governing the provision of piped municipal water supply in Mumbai became linked to the policy frameworks governing eligibility for a property titling scheme. This article outlines the ideological basis and practical implications of the shift, as well as the contradictions of the new regulatory regime. The article demonstrates how these contradictions have been mediated by the material and practical knowledge, embodied expertise, local authority and wide‐ranging socio‐political work of two sets of actors: municipal water engineers and a cast of characters known locally as ‘plumbers’. The social, political and hydraulic imaginaries animating the work of ‘plumbing’ are bound up with a temporal and spatial imaginary distinctly at odds with the network‐flow conception of hydraulic engineering within which the work of water supply planning and distribution in Mumbai is conceptualized, materialized and institutionalized. The hydraulic and legal contradictions of these clashing infrastructural idioms––of flow and event––have rendered the regulatory framework highly unstable. These contradictions eventually erupted in Mumbai's waterscape, leaving the city's water infrastructures suspended in a highly politicized state of limbo between dueling infrastructural imaginaries.  相似文献   
9.
Replacing conventional vehicle taxis with electric vehicles would be an efficient measure to reduce greenhouse gas emissions. Due to the limited range and long charging times of current battery electric vehicles, it is of utmost importance to provide sufficient charging facilities. This article analyses the impact of the placement and charging power of charging stations on potential mileage and revenue of electric taxis on the example of Singapore. Therefore, we developed an agent-based electric taxi simulation model to investigate electric taxis’ driving profiles with respect to different vehicle types and charging infrastructure designs. This model is also capable of simulating conventional taxi driving profiles. The validation of these simulation results with real taxi data showed that the model is reproducing taxi driving profiles with high accuracy in great detail. We found out that electric taxis could reach the same mileage and revenue as conventional taxis if charging with a power of 160?kW is possible. Furthermore, we discovered that waiting times for available charging stations have a stronger effect on revenue than the length of detours to reach charging stations. Based on these findings, we concluded that it is more important to reduce waiting times by placing sufficient numbers of charging stations at each location before expanding the charging network by installing small numbers of charging stations at many locations.  相似文献   
10.
Improving fuel economy and lowering emissions are key societal goals. Standard driving cycles, pre-designed by the US Environmental Protection Agency (EPA), have long been used to estimate vehicle fuel economy in laboratory-controlled conditions. They have also been used to test and tune different energy management strategies for hybrid electric vehicles (HEVs). This paper aims to estimate fuel consumption for a conventional vehicle and a HEV using personalized driving cycles extracted from real-world data to study the effects of different driving styles and vehicle types on fuel consumption when compared to the estimates based on standard driving cycles. To do this, we extracted driving cycles for conventional vehicles and HEVs from a large-scale U.S. survey that contains real-world GPS-based driving records. Next, the driving cycles were assigned to one of three categories: volatile, normal, or calm. Then, the driving cycles were used along with a driver-vehicle simulation that captures driver decisions (vehicle speed during a trip), powertrain, and vehicle dynamics to estimate fuel consumption for conventional vehicles and HEVs with power-split powertrain. To further optimize fuel consumption for HEVs, the Equivalent Consumption Minimization Strategy (ECMS) is applied. The results show that depending on the driving style and the driving scenario, conventional vehicle fuel consumption can vary widely compared with standard EPA driving cycles. Specifically, conventional vehicle fuel consumption was 13% lower in calm urban driving, but almost 34% higher for volatile highway driving compared with standard EPA driving cycles. Interestingly, when a driving cycle is predicted based on the application of case-based reasoning and used to tune the power distribution in a hybrid electric vehicle, its fuel consumption can be reduced by up to 12% in urban driving. Implications and limitations of the findings are discussed.  相似文献   
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