排序方式: 共有118条查询结果,搜索用时 15 毫秒
31.
赵晨生 《铁路工程造价管理》2014,(1):42-44
铁路工程EPC模式,基本涵盖了建设工程的全过程。铁路勘察设计单位作为EPC建设项目的总承包单位,如何在施工阶段进行施工进度管理和控制,此文结合大连机车接轨区工程,针对内外部影响因素进行分析,通过分析与研究,提出可采取的内外部影响因素控制措施,保证建设项目的J,l~,ffq实施。并为勘察设计单位进行施工阶段的进度管理和控制提供借鉴。 相似文献
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针对现有方法在实际应用时的标记样本稀缺与测试样本数据分布偏移等问题,提出一种基于语音特征迁移学习的驾驶疲劳检测方法。通过基于迁移学习的特征空间变换,对源领域有标记样本与目标域无标记样本数据间的边缘分布、条件分布、流形结构进行联合适配及降维处理,以解决样本数据分布偏移和特征维度过高的问题。以半监督学习的方式来迭代优化目标域样本的伪标记,并据此不断更新特征变换方式和迁移分类器,进而提高疲劳检测模型的精度和泛化能力。通过实验将本文方法与现有常用的监督学习、半监督学习和迁移学习等方法进行对比。结果表明,在测试时间、应用场景和被试个体均发生变化的情况下,本文所提方法的驾驶疲劳检测效果显著优于现有方法,正确率最高达到86.7%,具有实际应用价值。 相似文献
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曾艳英 《广东交通职业技术学院学报》2011,10(3):73-76,87
文中针对全国和广东省物流业现状与人才需求,为促进教学、科研和人才培养质量的全面提升,提出高职物流管理专业人才培养的“五个优化”措施:优化专业设置方向;优化课程设置、课时分配和课程内容;优化素质教育人才培养过程;优化教师队伍结构;优化校企合作。 相似文献
34.
乘用车废气旁通式涡轮增压器匹配技术 总被引:1,自引:0,他引:1
文章旨在解决使用传统方法进行匹配乘用车废气旁通式涡轮增压器涡轮匹配过程存在的不足。使用传统定压增压系统的涡轮增压器匹配方法,即将算术平均值作为计算边界,不适用于乘用车发动机增压器的匹配,特别是小排量(<1.6L)3缸发动机,低速脉冲能量大,匹配结果与实际试验结论相差较大。文章引用脉冲修正系数对涡轮等熵效率进行修正,从而使匹配结果与实际试验结果相接近,实现更准确的匹配工作。 相似文献
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Network effects of intelligent speed adaptation systems 总被引:2,自引:0,他引:2
Intelligent Speed Adaptation (ISA) systems use in-vehicle electronic devices to enable the speed of vehicles to be regulated automatically. They are increasingly appreciated as a flexible method for speed management and control particularly in urban areas. On-road trials using a small numbers of ISA equipped vehicles have been carried out in Sweden, the Netherlands, Spain and the UK. This paper describes the developments made to enhance a traffic microsimulation model in order to represent ISA implemented across a network and the impact of this on the networks. The simulation modelling of the control system is carried out on a real-world urban network, and the impacts on traffic congestion, speed distribution and the environment assessed. The results show that ISA systems are more effective in less congested traffic conditions. Momentary high speeds in traffic are effectively suppressed, resulting in a reduction in speed variation which is likely to have a beneficial impact on safety. Whilst ISA reduces excessive traffic speeds in the network, it does not affect average journey times. In particular, the total vehicle-hours travelling at speeds below 10 km/hr have not changed, indicating that the speed control had not induced more slow-moving queues to the network. A statistically significant, eight percent, reduction in fuel consumption was found with full ISA penetration. These results are in accordance with those from field trials and they provide the basis for cost-benefit analyses on introducing ISA into the vehicle fleet. However, contrary to earlier findings from the Swedish ISA road trials, this study suggested that ISA is likely to have no significant effect on emission of gaseous pollutants CO, NOx and HC. 相似文献
37.
Matthew Barth Kanok Boriboonsomsin 《Transportation Research Part D: Transport and Environment》2009,14(6):400-410
Surface transportation consumes a vast quantity of fuel and accounts for about a third of the US CO2 emissions. In addition to the use of more fuel-efficient vehicles and carbon-neutral alternative fuels, fuel consumption and CO2 emissions can be lowered through a variety of strategies that reduce congestion, smooth traffic flow, and reduce excessive vehicle speeds. Eco-driving is one such strategy. It typically consists of changing a person’s driving behavior by providing general static advice to the driver (e.g. do not accelerate too quickly, reduce speeds, etc.). In this study, we investigate the concept of dynamic eco-driving, where advice is given in real-time to drivers changing traffic conditions in the vehicle’s vicinity. This dynamic strategy takes advantage of real-time traffic sensing and telematics, allowing for a traffic management system to monitor traffic speed, density, and flow, and then communicates advice in real-time back to the vehicles. By providing dynamic advice to drivers, approximately 10–20% in fuel savings and lower CO2 emissions are possible without a significant increase in travel time. Based on simulations, it was found that in general, higher percentage reductions in fuel consumption and CO2 emission occur during severe compared to less congested scenarios. Real-world experiments have also been carried out, showing similar reductions but to a slightly smaller degree. 相似文献
38.
Brenda B. Lin Tim Capon Art Langston Bruce Taylor Russ Wise Rachel Williams 《Coastal management》2017,45(5):384-405
Climate change adaptation presents a difficult challenge for coastal towns around the world, forcing local governments to plan for sea level rise in a contentious decision-making space. The concept of “adaptation pathways,” a diagnostic and analytical tool to assist in adaptive planning and decision-making, is gaining traction as a way of framing and informing climate adaptation. It provides decisionmakers a way to acknowledge the inter-temporal complexities and uncertainties associated with the novel dynamics of climate change and a mechanism to manage these challenges in the local context. In 2012, the Australian Government funded an 18-month program to provide decisionmakers in the coastal zone an opportunity to test the utility of the adaptation pathways concept for coastal climate adaptation. Using a selection of completed projects as case studies, we performed a document analysis to better understand the learnings from the projects. The main themes surrounded: (1) the utility of the adaptation pathway framework in developing options, (2) decision-making rationale and criteria, and (3) stakeholder participation in pathway development. A project participant survey was developed to further understand these themes. Our analysis reveals that “adaptation pathways” was generally framed narrowly and conservatively to emphasize extant economic, administrative and legal considerations over community, participatory, or exploratory ones. Although some case study projects were able to reach a point in the pathway discussion to actively involve stakeholders in their decision-making process, many case studies continued to build technical data as a method for defending policies and actions. These results indicate that coastal adaptation can take-up adaptation pathways as a useful concept for decision-making and planning; however, many councils may still require assistance in stakeholder communication processes in order to develop sociallyacceptable plans that take into account the full range of values affecting local coastal environments. 相似文献
39.
The present study is designed to investigate social influence in car-sharing decisions under uncertainty. Social influence indicates that individuals’ decisions are influenced by the choices made by members of their social networks. An individual may experience different degrees of influence depending on social distance, i.e. the strength of the social relationship between individuals. Such heterogeneity in social influence has been largely ignored in the previous travel behavior research. The data used in this study stems from an egocentric social network survey, which measures the strength of the social relationships of each respondent. In addition, a sequential stated adaptation experiment was developed to capture more explicitly the effect of social network choices on the individual decision-making process. Social distance is regarded as a random latent variable. The estimated social distance and social network choices are incorporated into a social influence variable, which is treated as an explanatory variable in the car-sharing decision model. To simultaneously estimate latent social distance and the effects of social influence on the car-sharing decision, we expand the hybrid choice framework to incorporate the latent social distance model into discrete choice analysis. The estimation results show substantial social influence in car-sharing decisions. The magnitude of social influence varies according to the type of relationship, similarity of socio-demographics and the number of social interactions. 相似文献
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基于遗传算法的排课系统 总被引:1,自引:0,他引:1
随着高校的发展,在教务管理系统中使用的排课模型也变得越来越复杂,亟需一种适用于开发、重用及设计的方法。针对这种情况,本文给出了排课问题的数学模型,提出基于遗传算法解决方案。结果表明,该算法能比较有效的解决排课问题。该方法易于学习和应用,且不必依赖特殊的实现模式。 相似文献