Carbon monoxide spatial gradients over source regions as observed by SCIAMACHY: A case study for the United Kingdom

Carbon monoxide (CO) is an important air pollutant whose emissions and atmospheric concentrations need to be monitored. The measurements of the SCIAMACHY instrument on ENVISAT are sensitive to CO concentration changes at all atmospheric altitude levels including the boundary layer. The SCIAMACHY CO measurements therefore contain information on CO emissions. Until now no studies have been published where the SCIAMACHY CO measurements have been used to quantify CO emissions by applying, for example, inverse modelling approaches. Here we report about a step in this direction. We have analysed three years of CO columns to investigate if spatial gradients resulting from United Kingdom (UK) CO emissions can be observed from space. The UK is an interesting target area because the UK is a relatively well isolated CO source region. On the other hand, the UK is not the easiest target as its emissions are only moderate and because the surrounding water has low reflectivity in the 2.3 μm spectral region used for CO retrieval. We determined horizontal CO gradients from seasonally and yearly averaged CO during 2003–2005 over the UK taking into account daily wind fields. We show that the measured CO longitudinal (downwind) gradients have the expected order of magnitude. The estimated 2σ error of the gradients depends on time period and applied filtering criteria (e.g., land only, cloud free) and is typically 10–20% of the total column. The gradients are barely statistically significant within the 2σ error margin. This is mainly because of the relatively high noise of the SCIAMACHY CO measurements in combination with a quite low number of measurements (∼100) mainly due to cloud cover.     

引入案例教学方法改进空域规划课程教学

《空域规划》课程是空中交通管理专业的一门专业必修课,具有很强的实践性和研究实用性。通过介绍案例教学方法,阐述案例教学方法在空域规划课程中的应用,讨论案例教学时应注意的问题。引入案例式教学方法,加强理论知识的理解,提高学生的实践能力,增强学生的学习兴趣,取得较为满意的教学效果,为深化空域规划课程改革打下一定的理论基础。     

UV disinfection system for cabin air

The air of indoor cabin environments is susceptible to contamination by airborne microbial pathogens. A number of air treatment processes are available for inactivation or removal of airborne pathogens; included among these processes is ultraviolet (UV) irradiation. The effectiveness of UV-based processes is known to be determined by the combined effects of UV dose delivery by the reactor and the UV dose–response behavior of the target microbe(s). To date, most UV system designs for air treatment have been based on empirical approaches, often involving crude representations of dose delivery and dose–response behavior. The objective of this research was to illustrate the development of a UV system for disinfection of cabin air based on well-defined methods of reactor and reaction characterization.     

对廊坊市道路交通车流量管理现状的调查与对策研究

随着世界城市化的进展和汽车的普及,廊坊市出现了交通问题,像交通拥挤加剧、交通事故频繁、交通环境恶化等问题变得日趋严重,给人们的生活造成了严重影响.针对廊坊市目前的车流量管理现状的调查,提出解决廊坊交通问题的对策--实施"公交优先"是解决交通问题的主要途径和出路之一.本文分析了采用"公交优先"的必要性,并提出行之有效的措...     

Measuring the economic benefits of an environmental monitoring satellite project: The value of information approach

This paper reports a first application of contingent valuation method to measure the value of information generated by earth science data from an environmental geostationary satellite payload called Geostationary Environmental Monitoring Satellite. The purpose of the space project is to improve the accuracy of air pollution information by enhancing air pollution monitoring and forecasting system coupled with conventional ground level monitoring stations located throughout South Korea.     

系统仿真及其在防空导弹武器系统研制中的应用

阐述了仿真、仿真模型和仿真系统的应用特点和关键技术，并以战术导弹为例探讨了系统仿真在武器系统研制、试验和降低成本中的重要作用；介绍了国外８０年代以来发展的分布交互式仿真（ＤＩＳ）系统，它们既包括虚拟仿真，也可将真实仿真和构造仿真接入仿真系统，使仿真的范围大为扩展。ＤＩＳ技术构建的人工合成环境，是一个多武器平台的网络式综合仿真系统，具备人机交互功能，可进行武器研究和大系统虚拟对抗演习等；最后，提出了研究和发展我国防空武器仿真系统的几点建议。     

空中交通网络管理的概念与策略研究

提出以空中交通网络为主要研究对象的解决空中交通管理的思路,定义了空中交通网络的概念,并对空中交通网络管理的策略和机制进行了探讨。     

基于最小二乘估计原理的飞机流量预测

流量预测是空域评估管理系统的重要组成部分，目前流量的预测方法主要有回归分析和时间序列方法。应用系统辨识理论介绍了最小二乘格式模型在空中交通流量预测中的应用，以全国为例，根据所建立的模型对飞机的年流量进行了预测，并与回归分析方法做比较，说明了该方法的有效性。     

航天飞机用LACE方案的发展及其参数分析

研究了应用于空天飞机的液体空气循环发动机。介绍了提高空气液化比的几种方法，如：液氢，液氧储箱循环，液氧喷洒，液态空气喷洒。以能量平衡为基础，计算了液体循环发动机的循环参数。结果表明综合采用以上方法可以使液化比提高约６５％。     

空中交通管制员工作任务分析

简要说明了管制员工作任务分析的意义和重要性,介绍了管制员综合工作任务分析的方法,并以实际管制单位的管制员为研究对象,确定了管制工作中10大工作任务以及任务间的相互关系,最后对每个任务进行详细分析,构建了管制员10大任务模型。