CBERS-1卫星红外多光谱扫描仪图像预处理方法

文章介绍了中国和巴西联合研制的资源一号卫星 (CBERS_1)上的有效载荷之一 - -红外多光谱扫描仪 (IRMSS)图像数据的处理 ,包括错位校正、相对辐射校正和去除噪声等处理过程。     

从图像信息容量和图像功率谱看 CBERS-1卫星图像

文章从信息容量和图像功率谱这两个方面评价了CBERS-1的图像质量。并通过将同一地区的CBERS-1图像和TM图像进行比较,客现反映了CBERS-1卫星的图像质量。实验结果表明CBERS-1图像在信息丰富程度和图像综合的纹理特征上与TM图像质量相当,具有很好的可比性。     

305m长线缆的回波损耗和近端串扰的测试方法研究

数字平衡线缆广泛应用于综合布线系统以连通设备、互传信息,是工程建设中最常用的传输介质,其质量是保证信息顺利传递的关键,目前国际上通行的测试标准和方法均是基于90m长度的基线模型,而数字平衡线缆在工厂制造中通常是以1 000ft(305m)为基本单位进行绕匝装箱。因此为方便对生产线缆进行性能检测和质量控制,针对整箱线缆的测试方法研究尤为必要。文章提出针对305m长线缆的回波损耗和近端串扰的测试方法,利用网络分析仪和阻抗转换器实现对双绞线所有线对的近端性能测试,并与国际标准进行对比,验证了可以通过测试305m长线缆的回波损耗和近端串扰值来初步判断线缆的传输质量是否合格。     

Statistical characteristics of locally generated ESF during equinoctial months over Sanya

Understanding the local generation rate of equatorial spread-F (ESF) is important for forecasting ionospheric scintillation. Using the GPS ionospheric scintillation/TEC and VHF radar data during March-April and September-October from 2010 to 2014, the occurrence of ionospheric scintillation, TEC fast fluctuation, and backscatter plume were studied. Through analyzing the simultaneous occurrence of ionospheric scintillation, TEC fast fluctuation and backscatter plume, the local generation rate of ESF over Sanya was investigated. The results show that the monthly generation rate varies between 0% and 68%. A significant equinoctial asymmetry of local generation rate of ESF can be found in 2010, 2013 and 2014. The local generation rate of ESF increases from 2010 to 2014 during March-April, while it does not have similar trend during September-October. The plasma vertical drift influenced by solar activity has a significant impact on the monthly generation rate. The equinoctial asymmetry of plasma vertical drift may contribute a lot to the equinoctial asymmetry of the generation rate of ESF.     

Estimation of probability of occurrence of F1 layer or L condition using tables and electron density profile models

An algorithm is proposed for evaluation of the probability of occurrence of an F1 layer or L condition, based on tables. Observations independent of the tables database are used for comparison between the estimated probability of occurrence, the formulation used at present in IRI, and the occurrence actually observed. The importance of the inclusion of L condition in the electron density profile model is shown.     

A multi-objective multi-memetic algorithm for network-wide conflict-free 4D flight trajectories planning

Under the demand of strategic air traffic flow management and the concept of trajectory based operations (TBO),the network-wide 4D flight trajectories planning (N4DFTP) problem has been investigated with the purpose of safely and efficiently allocating 4D trajectories (4DTs) (3D position and time) for all the flights in the whole airway network.Considering that the introduction of large-scale 4DTs inevitably increases the problem complexity,an efficient model for strategic level conflict management is developed in this paper.Specifically,a bi-objective N4DFTP problem that aims to minimize both potential conflicts and the trajectory cost is formulated.In consideration of the large-scale,high-complexity,and multi-objective characteristics of the N4DFTP problem,a multi-objective multi-memetic algorithm (MOMMA) that incorporates an evolutionary global search framework together with three problem-specific local search operators is implemented.It is capable of rapidly and effectively allocating 4DTs via rerouting,target time controlling,and flight level changing.Additionally,to balance the ability of exploitation and exploration of the algorithm,a special hybridization scheme is adopted for the integration of local and global search.Empirical studies using real air traffic data in China with different network complexities show that the pro posed MOMMA is effective to solve the N4DFTP problem.The solutions achieved are competitive for elaborate decision support under a TBO environment.     

液冷模块的热仿真分析

运用基于CFD的热仿真软件Flotherm对液冷模块进行了热仿真分析,分别研究了在不同环境温度,不同冷却液流量以及不同冷却液温度条件下,液冷模块内部温度场的变化规律。仿真分析结果表明,环境温度对液冷模块的温度场影响非常小;液冷模块冷却液流量的增幅与元器件温度的降幅并非正比关系;元器件温度的升幅与冷却液温度的增幅相同。     

航空发动机总温热电偶校检问题

由于航空总温热偶气动构件的复杂性，校验问题一直悬而未决。制成后的电偶热电特性迁移，及配套特性变化强调了配套校验是必要的。本文在着重分析了以上问题后，介绍了自行研制的已获国家专利的ＳＴＴ－１Ａ系列总温热电偶校验器。     

新四六级考试和大学英语教学的改革

通过考前辅导和对考试结果的研究分析，发现学生在听读写几个方面都存在普遍性的问题，使我们教师不得不反思我们目前的大学英语课堂教学，并痛下决心，锐意改革，使我们的教学符合时代和社会的要求，提高学生的英语实际综合应用能力，更好地为社会服务。     

国际空间站日本舱信息系统早期设计分析

文章基于国际空间站日本实验舱早期总体定义阶段的活动研究成果，概述了日本实验舱信息系统的结构、通信链路环境、系统基本组成要素，并详细介绍了信息系统的需求、功能、子系统、硬件架构、软件结构以及与美国舱信息接口等关键点。最后总结分析了日本实验舱信息系统的典型特点，包括通信链路备份、核心网络与有效栽荷网络相互独立、数据传输线路优化、分层控制体系、光技术应用、CCSDS标准应用、软件分层模块化设计等。