最佳纠错码的快速译码

论文介绍了纠８位突发错误的最佳码的构造和截短，给出了基于字节运算的快速译方法及实现步骤，此法的一般性还可推广应用到共它循环码。     

铁路建设项目环境影响后评价指标体系初步研究

在目前国内外研究现状的基础上,结合铁路建设项目的特点,初步建立了以生态环境、噪声与振动环境、电磁环境、水环境、大气环境、固体废弃物和社会环境等7个互为关联和补充环境因子构成的铁路建设项目环境影响后评价指标体系,并利用构建的指标体系对成都至都江堰铁路环境影响后评价进行了分析。     

鼓式制动器摩擦副压强不均匀性分析与评价

定义了鼓式制动器摩擦片压强的两种不均匀度指数，推导了现有的不同机构型式的鼓式制动器的摩擦副压强不均匀度指数的计算公式，并分析了其变化特性。以这两种压强不均匀度指数作为新的评价指标，对各种型式的鼓式制动器进行了评价，揭示了一些型式的鼓式制动器所固有的缺点。提出了改进传统鼓式制动器的技术方向和途径。     

公共交通接驳换乘系统评价指标体系的构建

依照公共交通接驳换乘系统评价指标体系的构建原则,提出评价指标体系由技术性、经济性、社会性评价指标构成,并对各指标的含义做出解释,最后以北京地铁13号线部分车站作为实例,对技术性评价指标加以应用。论述一套合理的公共交通接驳换乘系统评价指标体系如何有效解决公共交通换乘效率低的问题。     

Predicting the Dielectric Strength of c-C4F8 and SF6 Gas Mixtures by Monte Carlo Method

An improved Monte Carlo method was used to simulate the motion of electrons in c-C_4F_8 and SF_6 gas mixtures for pulsed townsend discharge. The electron swarm parameters such as effective ionization coefficient, [AKα-] and drift velocity over the E/N range from 280～700 Td(1Td=10-21 V·m2) were calculated by employing a set of cross sections available in literature. From the variation cure of [AKα-] with SF_6 partial pressure p, the limiting field (E/N)_lim of gas mixture at different gas content was determined. It is found that the limiting field of c-C_4F_8 and SF_6 gas mixture is higher than that of pure SF_6 at any SF_6 mixture ratio. Simulation results show excellent agreement with experiment data available in previous literature.     

城市轨道交通乘客满意度评价体系的构建

对城市轨道交通如何建立乘客满意度测评指标体系进行研究,在把握整体的基础上,分析运营部门如何对服务水平的关键点进行控制与管理,为管理者建立符合自身实际情况的乘客满意度评价体系提供参考依据.     

城市轨道交通的旅行速度与列车拥挤度

从满足乘客出行需求的角度阐述城市轨道交通列车旅行速度、拥挤度两项指标的重要意义,并以当前我国典型的一线、二线城市轨道交通旅行速度、拥挤度的指标水平和提升过程为实例,分析这两项指标的计算方法、核心要素以及相互关系,从而提出新线开通运营前合理确定和开通运营后不断提升这两项核心指标的具体方法和措施:从优化司机站务人员站台作业标准流程、减少车辆开关门时间和同步延时时间、缩小列车区间运行时间余量等方面提高旅行速度;在开通初期可以通过增加上线列车数、中期可以通过提高旅行速度和折返效率的方法来降低列车拥挤度,而后期则需要研究采用大小交路套跑、上下行不对称运输、平行线路建设、新车增购等方式来从根本上降低列车拥挤度,不断提高乘客服务水平。     

GSM-R无线网络切换的关键指标研究

根据GSM-R无线网络切换的特点,对切换的几个关键技术指标进行重点分析,提出衡量GSM-R网络切换质量的几个关键指标,为网络优化提供关键参数。     

舰船设计方案评估指标体系研究

针对舰船研制特点,运用系统工程原理,通过对任务目标的分解与技术指标的分析,考虑全系统、全寿命、满足用户需求,将传统工程设计与现代专业工程进行系统综合,构建了可用于舰船研制方案的评估、权衡、优化的舰船研制指标体系.此外对其应用条件和应用形式进行了初步探讨.     

Fluxes of dissolved inorganic carbon in three estuarine systems of the Cantabrian Sea (north of Spain)

The diffusive and in situ fluxes of dissolved inorganic carbon (DIC) and total alkalinity (TA) have been measured and an estimation has been made of the water–atmosphere fluxes of CO₂ in three estuarine systems of the Cantabrian Sea during the spring of 1998. Each of these systems undergoes a different anthropogenic influence. The diffusive fluxes of dissolved inorganic carbon and total alkalinity obtained present values ranging between 0.54–2.65 and 0.0–2.4 mmol m⁻² day⁻¹, respectively. These ranges are in agreement with those of other coastal systems. The in situ fluxes are high and extremely variable (35–284 mmol TA m⁻² day⁻¹, 43–554 mmol DIC m⁻² day⁻¹ and 22–261 mmol dissolved oxygen (DO) m⁻² day⁻¹), because the systems studied are very heterogeneous. The values of the ratio of the in situ fluxes of TA and DIC show on average that the rate of dissolution of CaCO₃ is 0.37 times that of organic carbon oxidation. Equally, the interval of variation of the relationship between the benthic fluxes of inorganic carbon and oxygen (F_DIC/F_DO) is very wide (0.3–13.9), which demonstrates the different contributions made by the processes of aerobic and anaerobic degradation of the organic matter, as well as by the dissolution–precipitation of CaCO₃. The water–atmosphere fluxes of CO₂ present a clear dependence on the salinity. The brackish water of these systems (salinity<20), where maximum fluxes of 989 mmol m⁻² day⁻¹ have been estimated, act as a source of CO₂ to the atmosphere. The more saline zones of the estuary (salinity>30) act as a sink of CO₂, with fluxes between −5 and −10 mmol m⁻² day⁻¹.