基于船舶操纵性的最后避让距离数学模型

在几何避碰数学模型中加入船舶转向延时及延时中两船位置关系的变化,并省去有关会遇几何关系的假设,给出两船任意初始状态下,转向完成时目标船DCPA、TCPA的预算模型。安全避让条件是关于DCPA、TCPA的不等式组,其解是开始避让距离d与转向角度ΔC的平面域,解域中d的最小值即对应最后避让距离,且对应一特定转向角度值。此模型对船舶避碰时机决策具有实用价值。     

浅谈企业财务管理

企业财务管理是企业发展的关键,其贯穿于企业经营活动的全过程,是企业经营活动的重要组成部分,做好企业管理应该遵循五个方面的原则。     

青岛奥帆赛期间交通组织规划研究

<正>2008奥帆赛即将在青岛举办,这对青岛市的交通系统提出了考验。依据历届举办奥运会的经验教训来看,奥运期间交通状况是否良好,交通管理是否高     

蓄电池智能充放电及性能评估系统的研制

随着铁路体制改革的不断深入，机车检修模式也发生了较大变化。蓄电池作为修程中必不可少的检修范围，其质量好坏直接关系着机车的正常运用。为此，对智能化、状态自动评估的蓄电池充放电系统进行探讨和研制，阐述了该系统需具备的条件、工作原理、模块功能组成及技术要求，以及预期达到的效果。     

关于桥梁工程划分及质量检验评定的探讨——交通标准与市政标准的差异

讨论了交通标准与市政标准的桥梁工程在工程划分及工程质量检验评定方法上的差异，并提出了解决问题的建议。     

京沪线成功铺设30号道岔

为了配合1998年10月1日京沪线再次提速,全路第一组60公斤/米钢轨30号可动心轨道岔,于1998年9月初在蚌埠分局管内831线路所铺设成功。 该道岔允许直向通过速度200公里/小时,侧向通过速度140公里/小时。道岔全长102.4米,重达180多吨,尖轨长27.98米,前后共配有9台     

Research on High Power Inter-Channel Crosstalk Attack in Optical Networks

While all-optical networks become more and more popular as the basis of the next generation Internet(NGI)infrastructure,such networks raise many critical security issues.High power inter-channel crosstalk attack is one of the security issues which have negative effect on information security in optical networks.Optical fiber in optical networks has some nonlinear characteristics,such as self phase modulation(SPM),cross phase modulation(XPM),four-wave mixing(FWM)and stimulated Raman scattering(SRS).They can be used to implement high power inter-channel crosstalk attack by malicious attackers.The mechanism of high power inter-channel crosstalk attack is analyzed.When an attack occurs,attack signal power and fiber nonlinear refractive index are the main factors which affect quality of legitimate signals.The effect of high power inter-channel crosstalk attack on quality of legitimate signals is investigated by building simulation system in VPI software.The results show that interchannel crosstalk caused by high power attack signal leads to quality deterioration of legitimate signals propagated in the same fiber.The higher the power of attack signal is,the greater the fiber nonlinear refractive index is.The closer the channel spacing away from the attack signal is,the more seriously the legitimate signals are affected by attack.We also find that when attack position and power of attack signal are constant,attack signal cannot infinitely spread,while its attack ability shows a fading trend with the extension of propagation distance.