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951.
952.
随着经济的发展,交通设计是解决大城市交通拥挤的一种有效措施。以北京市京开高速公路桥下道路改造工程设计为例,阐述了交通设计在城市道路工程设计中是如何应用的,以期对其它正在进行道路交通建设的城市具有参考作用。 相似文献
953.
从交通方式分担的特性出发,分析了其主要影响因素的影响机理,通过详细的交通调查、调研,从城市规模、城市形态、经济水平等城市特性的角度进行了深入研究,理清各因素之间的因果关系、逻辑关系,为准确的交通方式分担预测打下基础。 相似文献
954.
Ray Wyatt 《Urban Policy and Research》2013,31(1):8-12
Abstract How to guard against misinterpreting questionnaire data is explained, using a survey of residents' environmental attitudes as an illustration. Environmental attitudes in streets having high-traffic, low-traffic and “rejuvenated” environments are discussed, along with the limitations of questionnaire data. 相似文献
955.
Digital penetrometers provide reliable assessments of snow penetration resistance with depth. However, extracting useful information from the signals relating to snow stability has proved to be challenging. In this study, penetrometer profiles were collected in close proximity to compression tests. A scheme for predicting the fracture character of weak layers in the compression tests from the penetrometer signals is presented. When a two-group classification between sudden (Q1) (an indicator of instability) and other fracture character groups was performed, potential failure layers were correctly classified 80% of the time. The variables offering the best discrimination between sudden and other categories were weak layer thickness, average force gradient above the weak layer, and both the average and the maximum force gradient below the weak layer. The effect of introducing randomly selected layers into the prediction scheme was also investigated. When such layers were introduced, the classification rate dropped to 67%, indicating that more effective fracture character prediction occurred when weak layers were manually pre-identified. This suggests that this scheme should be used in conjunction with a weak layer detection model rather than as a stand alone analytical technique for the purpose of critical weak layer identification. The classification rate dropped further to 55% when a more detailed, four-group classification scheme was used. 相似文献
956.
浅谈城市天然气居民用户气量预测 总被引:3,自引:2,他引:1
通过介绍居民用气量计算公式中用气量指标及气化率两个不确定参数的影响因素,阐述了居民用气量预测的难度及重要性,旨在通过分析掌握居民用气指标和用气规律,从而准确预测居民用气量。 相似文献
957.
Eduardo Gomes Salgado Luiz Alberto Beijo Paulo Sampaio Carlos Henrique Pereira Mello Pedro Saraiva 《国际生产研究杂志》2016,54(18):5416-5433
The ISO 9001 standard is considered as an effective tool to support a quality management system (QMS). A steady growth in the number of ISO 9001 issued certificates is observed worldwide, confirming the interest of companies in this approach. However, information regarding this behaviour over time in the American Continent is scarce. This paper presents a set of qualitative and quantitative analyses related to the ISO 9001 certification (globally and at the country level of the Americas), the use of this standard in countries that were part of the ISO Survey 2011 and modelling the ISO 9001 certification for American countries, in order to characterise through mathematical models, the evolution of the certification process and to identify factors that influence the ISO 9001 issued certificates in the various countries analysed. Based on the work developed, a positive relationship was found between the number of issued certificates in each country per 1000 inhabitants and the indicators of economic development (Gross National Income Per Capita). It is determined that the total reserves of a country is an economic variable that directly affects the number of issued certificates, a finding not observed in other forecasting models. 相似文献
958.
With the rapid development of Internet, it is increasingly convenient to obtain real-time traffic condition information, which has greatly stimulated the improvement of urban traffic guidance. Traffic conditions are generally divided into four grades in the existing network platform, which are expressed in different colours. The understanding of traffic condition is still at the level of abstract senses. Therefore, it is difficult to grasp the characteristics of urban traffic. To this end, a new idea is proposed in this paper, and the new idea is to study the urban traffic characteristics based on real-time traffic condition information extraction with image identification technology. With this method, we can not only quantify the abstract traffic condition information, but also solve the loss of traffic condition information. In addition, an instance is analysed in this paper, it shows that it can provide references for urban traffic organization management very well. 相似文献
959.
机械式立体汽车库设计要点初探 总被引:1,自引:1,他引:0
通过实际工程中的经验总结,指出机械式立体汽车库在节地、空间利用、安全、节能等方面具有突出优势,进而对机械式立体汽车库的设计要点进行了经验的总结和简要的剖析。 相似文献
960.
结合福建省南安市水头镇现状路网实际情况,深入分析了现状城镇化道路交通存在的主要问题,并针对性地提出了发展策略和建议,以确保其在城市化发展过程中少走弯路,也为其他类似小城镇路网规划积累了经验。 相似文献