New generic mathematical model to predict hydrodynamic interaction effects for overtaking maneuvers in simulators

To improve the formulation of ship–ship interaction forces and moments in a mathematical model of a ship maneuvring simulator, we developed a new generic mathematical model for the overtaking maneuver. This process involves using the numerical results, which provide a potentially complete set of data from which (within the constraints of the numerical modelling) everything necessary can be acquired. We found that the new generic mathematical model is as accurate as the numerical model. It is also more accessible to a navigator, master, or pilot, who could use it on a palmtop computer by keying in a few numberical estimates of the size, position, and speed of the neighboring ship and receive almost instant aneous results, giving time for a refined strategy to be validated if necessary. These results can also readily be used by simulation program developers to simulate the worst possible scenarios.     

F77船站手柄话机软件模拟器的研制

本文介绍了以VC＋＋6．0为技术平台实现F77船站手柄话机模拟京统的构想、软件的设计思路、编程技术分析和程序流程图。     

一种信号设备功能测试系统方案的研究

作为高安全需求领域,轨道交通领域对其信号设备的安全完善度等级有着极高的需求,必须在各设备联调联试之前先对单一设备进行深入完整的测试。本文以列控中心的测试为例,在对测试系统需求分析的基础上进行研究,提出了一种通用的系统级测试系统方案。     

NTSC-A型制冷模拟器控件开发及功能实现

NTSC-A型蒸汽压缩式制冷模拟器是由南通航运职业技术学院基于VB6.0软件平台研发的仿真教学设备,该仿真系统在教学和培训过程中取得了良好的效果。文章重点分析和介绍了仿真系统控制界面的开发过程及其功能实现方法,以期对实践教学具有一定的实践指导意义。     

网络仿真平台NS上的编程实现

网络仿真软件是网络性能理论分析、评估网络设计方案以及网络故障诊断的有力工具。随着网络规模的增大，各种网络方案和协议日趋复杂，仿真技术在现代通信网络设计中的作用越来越大。着重探讨网络仿真免费软件NS，首先分析了NS网络仿真器的体系结构，然后介绍了如何在NS环境下编程实现开发用户自己的仿真对象，对网络进行更加自主的仿真。     

Evaluating policies to reduce greenhouse gas emissions from private transportation

This paper proposes a model system to forecast household greenhouse gas emissions (GHGEs) from private transportation. The proposed model combines an integrated discrete-continuous car ownership model with MOVES 2014. Four modeling components are calibrated and applied to the calculation of GHGEs: vehicle quantity, vehicle type and vintage, miles traveled, and rates of GHGEs. The model is applied to the Washington D.C. Metropolitan Area. Three tax schemes are evaluated: vehicle ownership tax, purchase tax and fuel tax. We calculate that the average GHGEs per vehicle is 5.15 tons of carbon dioxide-equivalent (CO₂E) gases. Our results show that: (a) a fuel tax is the most effective way to reduce vehicle GHGEs, especially for households with fewer vehicles; (b) a purchase tax reduces vehicle GHGEs mainly by decreasing vehicle quantity for households with more vehicles; and (c) an ownership tax reduces vehicle GHGEs by decreasing both vehicle quantity and miles traveled.     

An integrated traffic-driving simulation framework: Design,implementation, and validation

This paper first describes the process of integrating two distinct transportation simulation platforms, Traffic Simulation models and Driving Simulators, so as to broaden the range of applications for which either type of simulator is applicable. To integrate the two distinct simulation platforms, several technical challenges needed to be overcome including reconciling differences in update frequency, coordinate systems, and the fidelity levels of the vehicle dynamics models and graphical rendering requirements of the two simulators. Following the successful integration, the integrated simulator was validated by having several human subjects drive a 2.5 mile long segment of a signalized arterial in both the virtual environment of the integrated simulator, and in the real-world during the evening “rush hour”. Several aspects of driving behavior were then compared between the human subjects’ driving in the “virtual” and the real world. The comparisons revealed generally similar behavior, in terms of average corridor-level travel time, deceleration/acceleration patterns, lane-changing behavior, as well as energy consumption and emissions production. The paper concludes by suggesting possible extensions of the developed prototype which the researchers are currently pursuing, including integration with a computer networking simulator, to facilitate Connected Vehicle (CV) and Vehicle Ad-hoc Network (VANET) related studies, and a multiple participant component that allows several human drivers to interact simultaneously within the integrated simulator.     

融合电子海图的AIS综合模拟器的研究与开发

船舶自动识别系统(Automatic Identification System,简称AIS)是一种新型的船舶辅助导航设备,国际海事组织已通过AIS强制性安装议案。为加强远洋船员对AIS设备操作的培训,利用计算机网络开发了AIS综合模拟器。实现对AIS信号采集处理后与计算机局域网络的信息转换,并且将电子海图与AIS显示完全融合在一起。该模拟器的研究与开发,不仅减少了设备投入,节约经费开支,提高培训的效果,而且适应了航海技术对AIS的发展需求,使教学具有超前性和先进性。     

六自由度汽车运动模拟器机构的位置姿态误差分析

六自由度汽车运动模拟器是可进行汽车驾驶逼真模拟的训练和研究用设备。本文利用微分平移和微分放置变换方法，通过误差传递矩阵的求解来探讨模拟器运动台主要误差源与运动台位置姿态误差之间的关系，建立了六自由度模拟器运动台的位置姿态误差模型。