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1.
The Changjiang River (Yangtze) is one of the fastest growth areas of container transportation in Chi-na. Rail, road and water transportation have competed against each other for container transportation in the Chang-jiang River main line and its delta area. It is of significance to assess these different transportation modes scientifi-cally in order to organize container transportation efficiently in this area and make decision for integral plan and construction of transportation system in this area. This paper outlines application of fuzzy comprehensive evaluation to appraise different modes of typical direction of containers. Twelve assessment indexes were decided. Membership functions were formulated. Evaluation results indicated that road transportation was optimal mode in the Changjiang River delta area, however water transportation was the primary way in the Changjiang River main line.  相似文献   
2.
房产测绘管理系统软件开发中的若干问题   总被引:7,自引:0,他引:7  
介绍了房产测绘管理系统开发过程中的几个关键的问题。分别对房产测绘管理系统的开发、运行环境、系统功能以及功能实现中的技术问题等进行了分析和探讨。  相似文献   
3.
以具体实例探讨了ActiveX控件在计算机辅助设计中的应用,给出了部分源代码。对这种新的设计思想作了概念性的剖析与展望。  相似文献   
4.
The role of the seismic soil–pile–structure interaction (SSPSI) is usually considered beneficial to the structural system under seismic loading since it lengthens the lateral fundamental period and leads to higher damping of the system in comparison with the fixed-base assumption. Lessons learned from recent earthquakes show that fixed-base assumption could be misleading, and neglecting the influence of SSPSI could lead to unsafe design particularly for structures founded on soft soils. In this study, in order to better understand the SSPSI phenomena, a series of shaking table tests have been conducted for three different cases, namely: (i) fixed-base structure representing the situation excluding the soil–structure interaction; (ii) structure supported by shallow foundation on soft soil; and (iii) structure supported by floating (frictional) pile foundation in soft soil. A laminar soil container has been designed and constructed to simulate the free field soil response by minimising boundary effects during shaking table tests. In addition, a fully nonlinear three dimensional numerical model employing FLAC3D has been adopted to perform time-history analysis on the mentioned three cases. The numerical model adopts hysteretic damping algorithm representing the variation of the shear modulus and damping ratio of the soil with the cyclic shear strain capturing the energy absorbing characteristics of the soil. Results are presented in terms of the structural response parameters most significant for the damage such as foundation rocking, base shear, floor deformation, and inter-storey drifts. Comparison of the numerical predictions and the experimental data shows a good agreement confirming the reliability of the numerical model. Both experimental and numerical results indicate that soil–structure interaction amplifies the lateral deflections and inter-storey drifts of the structures supported by floating pile foundations in comparison to the fixed base structures. However, the floating pile foundations contribute to the reduction in the lateral displacements in comparison to the shallow foundation case, due to the reduced rocking components.  相似文献   
5.
With the global container population exceeding 25 million TEU (Twenty-foot Equivalent Unit) and the annual production of new boxes exceeding 3 million TEU it is estimated that around 1.5 million TEU of empty containers are sitting in yards and depots around the world waiting for use. Although utilization rates have improved since 2004, container utilization depends on the very dynamic nature of container transportation, and the container building and leasing industries. Owing primarily to the chronic trend of increasing trade imbalances across the oceans, and despite recent trends along some trade routes, the empty container management problem has become a major issue for the container shipping industry during the last decade. This paper examines and analyzes empty container logistics at a global, interregional, regional and local level. Special consideration is given to key factors affecting the empty container logistics management and strategies implemented by ocean carriers and other stakeholders to better manage empty containers.
Maria BoileEmail:
  相似文献   
6.
We developed an automatic seismic wave and phase detection software based on PhaseNet, an efficient and highly generalized deep learning neural network for P- and S-wave phase picking. The software organically combines multiple modules including application terminal interface, docker container, data visualization, SSH protocol data transmission and other auxiliary modules. Characterized by a series of technologically powerful functions, the software is highly convenient for all users. To obtain the P- and S-wave picks, one only needs to prepare three-component seismic data as input and customize some parameters in the interface. In particular, the software can automatically identify complex waveforms (i.e. continuous or truncated waves) and support multiple types of input data such as SAC, MSEED, NumPy array, etc. A test on the dataset of the Wenchuan aftershocks shows the generalization ability and detection accuracy of the software. The software is expected to increase the efficiency and subjectivity in the manual processing of large amounts of seismic data, thereby providing convenience to regional network monitoring staffs and researchers in the study of Earth's interior.  相似文献   
7.
Docker等容器技术给GIS的部署带来了极大便利,并使快速规模部署成为可能.本文讨论了在容器环境中GIS服务状态的最佳同步方式、发现方式,以及如何更智能地实现GIS服务的负载均衡,并提出了一种应对负载均衡中单点失效的机制,为GIS服务的动态伸缩、故障恢复提供了借鉴.  相似文献   
8.
北冰洋东北航道夏季集装箱航运经济性研究   总被引:2,自引:1,他引:1  
近年来,随着全球变暖的大趋势,夏季北极海冰范围急剧缩小,为北极的国际航运迎来了机遇,夏季航行于俄罗斯东北航道的船只迅速增多。由于东北航道的距离远远小于传统亚欧航线,因此具有较高的航运价值,很多海运国家对此极为关注。本文通过成本分析法,计算亚欧集装箱航线采用东北航道时可节约的航运成本,对东北航道的经济优势作出评估。  相似文献   
9.
管道屈曲技术试验过程当中,发现深水压力舱的出厂自带密封工艺耗时过长、密封效果不好、安全性不佳、返工现象普遍.针对这一现象,采用全新的密封工艺流程与方法:在前期处理中对螺柱编号与清理以防止螺母安装过程中的卡死现象;采用自创的精度控制方法防止漏水以及返工;根据不同的工作压力对密封技术进行梯度划分,选取不同的密封方案.经过实...  相似文献   
10.
1 The Raising of the Problem 1.1 The development of the international container traffic At the end of the 1930s, the developed countries began to develop container traffic, following the first one established on land which prevailed marine transport after expansion in the 1970s and the 1980s. Then many junction ports had special container berths constructed throughout the world and all main transportation lines were containerized. With the development of the world trade and increase of the pr…  相似文献   
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