基于公路收费站的公路交通调查优化方法

交通调查是进行交通规划、交通设施建设、交通控制与管理以及交通流研究的基础,也为科学的决策提供依据。在分析收费站设置和交通调查点设置的对偶关系的基础上,提出将交通调查点和公路收费站相结合,建立依托收费站的数据采集系统来进行交通调查,并在大的范围内建立一个数据处理平台,处理交通流参数,研究其时间和空间分布特征。这将大大节省交通调查所需的人力、物力,节约资源,同时,数据的精确程度也会进一步提高。     

解读劳伦斯诗歌《灵船》中"死亡"之意象

劳伦斯一生创作的诗歌颇多,在诗集《最后的诗歌》中他对“死亡”意象的专注尤其引起后人的重视．在前人研究的基础上对《最后的诗歌》中颇具代表性的“死亡”主题的诗作《灵船》做一些具体分析,主要从语言层面、意象层面和意蕴层面全面而系统地解读劳伦斯诗歌《灵船》中“死亡”意象与宗教和社会现实等的内在关系,以期能更加全面地了解劳伦斯诗歌创作的整体思想和意图．     

Prediction analysis on propulsion shafting load based on grey system theory北大核心CSCD

[Objective]The propulsion shafting system is an important part of a ship, and the bearing load directly affects its operating state and service life. In this paper, bearing load under hull deformation is studied using grey system theory. [Method] First, according to the empirical formula of the relative displacement of each bearing caused by the deformation of the hull of a 57 000 DWT oil tanker, the relative displacement of each bearing is calculated and input into a finite element model, and the load value of each bearing is output. On this basis, grey relationship analysis of grey system theory is introduced to study the influence degree of stern bearing displacement on the load of each bearing, and the relative change of the load of each bearing caused by the displacement of the stern bearings is analyzed. A GM (1,1) prediction model is then established for the bearing load considering the bearing displacement conditions, and the hull deformation-fitting and prediction of each bearing load are made. [Results]The results show that grey relationship analysis can effectively reflect the influence of hull deformation on bearing load. The GM (1,1) prediction model has high accuracy and prediction errors less than 6.0%, and the model test indexes can represent the accuracy of the prediction. [Conclusion]Grey system theory is effective and practical in research on propulsion shaft load. It can accurately predict bearing load under bearing displacement, giving it certain reference value for research on bearing load under actual sailing conditions. © The Author(s) 2022.     

Estimating cycleway capacity and bicycle equivalent unit for electric bicycles

With the rapid increase of electric bicycles (E-bikes) in China, the heterogeneous bicycle traffic flow comprising regular bicycles and E-bikes using shared cycleway creates issues in terms of efficiency as well as safety. Capacity and bicycle equivalent units (BEUs) for E-bikes are two most important parameters for the planning, design, operation, and management of bicycle facilities. In this paper, eight traffic flow fundamental diagrams are developed for one-way cycleway capacity estimation, and a novel BEU estimation model is also proposed. Eleven datasets from different shared cycleway sections with different cycleway widths were collected in Hangzhou, China for estimation and evaluation purposes. The results indicate that, with around 70% share of E-bikes, the mean estimated capacity is 2348 bicycle/h/m. The effects on the capacity of the proportions of E-bikes, gender of cyclists, age of cyclists, and cyclists carrying things were also analyzed. The results implied that the estimated capacity is independent of a cyclist’s gender and age, but increases with the proportion of E-bikes. According to this study, the mean BEU for the E-bike is 0.66, and the converted capacities of pure regular bicycles and pure E-bikes are 1800 and 2727 bicycle/h/m, respectively. These findings can be used to propose practical countermeasures to improve the capacity of heterogeneous bicycle traffic flow on shared cycleway.     

产业结构与职业教育互动关系研究

经济的发展、产业的结构调整对于人才需求的变化,影响职业教育;而职业教育的发展反过来又影响产业结构的调整。产业结构与职业教育密不可分,二者存在着广泛的互动关系。产业结构影响职业教育的规模、质量、地区分布、层次结构、专业结构,职业教育发展状况对产业结构的优化升级有反作用。     

An exploration of the competitive relationship between intercity transport systems

A suitable model that enables the analysis of dynamic relationships between transport systems is important for managers to make real-time reaction strategies. This study proposes an autoregressive distributed lag modeling approach that can point a way to interpret the long- and short-term relationships between intercity transport systems. To test the applicability of the approach with regard to evaluating the dynamic competitive relationships between intercity transport systems, an empirical study sample is adopted in evaluating competition between high-speed rail (HSR) and intercity bus services. The results indicate that HSR has a long-run impact on intercity bus transport and the intercity bus transport market is positively affected by its previous operations and negatively influenced by the previous performance of HSR. However, in the short-run, the current period performance of HSR positively affects the intercity bus transport market.     

Understanding job-housing relationship and commuting pattern in Chinese cities: Past,present and future

There are debates about whether job-housing balance and short commuting distances could be achieved through government intervention in Western countries. However, few studies have been carried out in developing context. The present study aims to fill in this knowledge vacuum by studying how China’s changing socio-spatial context, particularly the spatial ideas of danwei, influences job-housing relationships and commuting patterns from a historical perspective. The results clearly show that the dominant trend in commuting patterns in Chinese cities has changed from intra-danwei commuting before 1978 to reverse commuting from the city center to the inner suburbs in 1978–1998, to long-distance suburb-to-city commuting since 1998. The findings suggest that government intervention could be helpful in achieving shorter commute in China, and that urban planning and policy that promote mixed land-use and job-housing balance should be considered. Some limitations of government intervention are also discussed.     

舰船总体多学科优化设计系统分解

舰船总体是一个复杂的大系统,具有层次多样性.按一定规则对舰船总体进行多学科设计优化（MDO）的系统分解是MDO的基础.分析舰船总体MDO的系统定义和舰船设计中各个对象、环节之间的耦合关系,以及典型系统对总体方案的影响因素;针对方案阶段舰船总体MDO,对舰船总体进行多学科的系统分解,确定舰船MDO的各系统（学科）,梳理出各子系统间的关系,提出舰船多学科的学科体系,构建系统间的耦合关系图.     

某滑坡滑带土应力-应变关系模型研究

通过巴东地区某滑坡滑带土的一系列物理性质试验以及不同剪切速率的滑带土重塑样的三轴固结不排水剪试验,确定了滑带土的岩土分类,分析了滑带土试样的应力-应变关系,利用试验数据对邓肯-张(Duncan-Chang)本构模型进行了曲线拟合,通过分析验证,认为Duncan-Chang模型的双曲线型关系能够较好地反映该滑坡滑带土的逐渐硬化类型的应力-应变特性,可以为该类型滑坡的数值模拟研究提供参考。     

基于系统动力学的国际陆港仿真研究

以昆明国际陆港为例,采用定性与定量相结合的研究方法,基于系统动力学仿真软件,对国际陆港与昆明市的经济系统进行建模仿真,系统研究了陆港与城市经济系统发展的主要影响因素及趋势特征,结果验证了该模型在国际陆港与城市经济系统研究方面的有效性.