Development of the Software for Calculating Tunnel Portal Structure Based on the Theory of Limit State Method北大核心CSCD

The limit states of railway tunnel portal structure including compression, tensile, anti-overturning, antisliding and bearing capacity of foundation should be considered when portal structure is designed based on the prob⁃ ability limit state method. In order to evaluate the reliability of portal structure, the reliability index and limit state of bearing capacities of different limit states need to be calculated. The traditional methods generally use hand compu⁃ tation combined with MATTLAB, ANSYS, EXCEL and other softwares, which has low computation efficiency and poor practicality. In view of above problems, a calculating software for portal structure was developed based on the probability limit state method and Visual Basic platform, which realizes the function of rapid calculation of reliabili⁃ ty index and limit state of bearing capacities under five limit states of portal structure, offers three methods to calcu⁃ late the reliability index including JC method, fractile method and Monte-Carlo method. Moreover, the calculation results can be written in the EXCEL template file, greatly improving the efficiency of tunnel portal structure calcula⁃ tion. The accuracy of the software is verified by comparing with the results of hand calculation. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.     

GIS-Based Grid Assessment Model of Shield Tunnel Conditions and Its Application北大核心CSCD

As the lack of guidancs for maintenance and repair of rail transit shield tunnels, this paper proposes a macroscopic method for grid assessment of shield tunnels. First, the tunnel serviceability index (TSI) is adopted as the tunnel condition assessment method and the results are compared with Chinese codes and the traditional fuzzy hierarchical comprehensive evaluation method. Second, based on the assumption that the factors affecting the conditions of the tunnels, such as the surrounding stratum environment, the structural overlying load and so on, are correlated spatially, the spatial variability theory is used for the grid assessment of shield tunnels. Finally, taking the Shanghai Rail Transit System as an example, the application results of the grid assessment method are described. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.     

观测低高度太阳方位计算罗经差的软件程序设计

通过观测低高度太阳方位计算罗经差是船舶在开阔大洋上航行时求罗经差常用的方法,为了能更加方便、快捷并且准确地求出罗经差,本文在基于Visual Basic（VB）环境的下设计开发了计算罗经差的Visual Basic（VB）软件程序。该软件程序可将观测及查表计算所得的数据直接输入,避免将所得数据类型进行转化再代入公式计算的繁锁,该软件程序能够减小求罗经差的计算量,提高求罗经差的速度、精度及准确率。通过与一般计算器求罗经差的实例进行对照,证明了该软件程序的实用性及应用该软件程序的优越性。     

浅析B型喇叭立体交叉的安全性

文章从喇叭型立体交叉的分类、特点及适用性入手,系统分析了车辆在B型喇叭立体交叉上行驶存在的安全隐患,并提出了针对性的安全保障措施。     

改扩建高速公路基本路段通行能力研究

文章以沪宁高速公路江苏段桩号为K104＋925两侧加宽（两侧拼接）的扩建基本路段为研究对象,利用VISSIM仿真软件,建立高速公路基本路段仿真模型,模拟车流的运行状态及其随时空变化的过程。通过对仿真运行过程的观察及实测数据的分析,对比研究了扩建前后高速公路基本路段的实际通行能力和服务水平。     

华能营口电厂取水工程的流场数值模拟

华能营口热电厂取水工程二维水流数学模型采用嵌套网格的差分格式进行模拟计算,分析了不同取水位置对流场的影响。计算结果表明,该方法对取水口所在水域具有足够的网格分辨率,能够满足大范围海域边界条件验证的要求和工程所在河口水域流场的特征,同时又能满足工程局部水域计算精度的要求,具备边界控制准确、地形概化灵活、模拟精度合理和运算效率高等优点。     

舰船电力系统中智能电网技术的应用浅析

智能电网技术具有能量优化分配、管理和控制方面的优势,但是舰船电力系统在能量来源、设计理念、可靠性等方面又有着特殊的要求。因此通过重点分析智能电网技术与舰船电力系统的协调性,探讨舰船电力系统应用和实现智能电网技术的重点和关键技术,提出舰船智能电网对信息集成技术、实时监测技术、智能决策技术的要求要远高于陆地智能电网,而且相应的智能装备研制,也必须考虑到应用的特殊环境,从而需要将自愈、智能对话、优质电能、电磁兼容和抗攻击性作为主要应用特征和发展重点,并重点关注和解决与之相关的灵活的电网结构、传感与测量技术、信息化技术、智能型设备等关键问题,开发出能与舰船系统有效结合的合适的智能电网,充分发挥智能电网技术的优势,推动舰船先进装备的研制,达到提高舰船整体作战能力的最终目的。     

OPC技术及其在工程船舶实时监控系统中的应用

本文简述了OPC技术的由来、特点、技术基础。以一工程船舶实时监控系统设计为例,详细介绍了利用VB开发OPC数据接口的步骤和关键技术。经实船运行验证,该系统运行稳定、可靠,具有一定的推广价值。     

Anticipating PEV buyers’ acceptance of utility controlled charging

Utility controlled-charging (UCC) of plug-in electric vehicles (PEVs) could potentially align vehicle charging with the availability of intermittent, renewable electricity sources. We investigated the case of a nightly charging program where the electric utility can control home PEV charging. To explore consumer acceptance of this form of UCC, we implemented a web-based survey of new vehicle buyers in Canada (n = 1470). The survey assessed interest in PEVs, explained UCC, and elicited openness to UCC through attitudinal questions and a stated choice experiment. We find potential for UCC support among one-half to two-thirds of respondents interested in purchasing a PEV, depending on the scenario. However, some respondents express concerns with privacy and loss of control. To quantify preferences for UCC, we estimated a latent class choice model where respondents chose between different PEV charging programs. The model identified four distinct respondent segments (or classes) that vary in their acceptance of UCC, as well as their valuation of renewable electricity, saving money on their electrical bill, and undergoing charging inconvenience. The overall sample was more sensitive to cost incentives than to renewable incentives, where cost-based UCC programs garnered 63–78% enrollment while renewable-based programs garnered only 49–59% enrollment. Overall, we observe the potential for widespread acceptance of UCC programs among Canadian PEV buyers, but program design and deployment will need to carefully acknowledge the various motivations and concerns of different vehicle buyer segments.     

运行ISM规则对船长管理素质要求的思考

ISM规则的强制实施,促使船舶的安全管理从原来的注重船舶硬件向管理软件转变,这对船长的管理素质提出了更高的要求。通过实施ISM规则对船长应具备的管理基本素质和技能的要求进行探讨,并提出提高船长管理素质的途径和方法的思考。