基于约束编程的飞机排班问题研究

飞机排班是航空运输生产计划的重要环节,对航空公司的正常运营和整体效益有着决定性影响.飞机排班通常构建为大规模整数规划问题,是航空运筹学研究的重要课题,构建的模型属于严重退化的NP Hard问题.本文把飞机排班问题构建为多商品网络流模型,并应用列生成算法求解;在列生成子问题中,引入约束编程系统实现快速求解航班连线（航班串）并计算各航班串简约成本,动态选择列集并与限制主问题进行迭代.最后,利用国内某航空公司干线航班网络实际数据验证模型和算法的有效性,并与航空公司实际排班进行比较研究.     

基于运行数据的航班运行关键风险因素推断

为降低由于运行控制人员个体差异导致的航班运行风险,提升航空公司运行 控制能力,通过对航班运行程序的系统分析,结合运行数据,从飞行机组、机场、天气、航 路和航空器等运行角度筛选风险因素,建立航班运行控制风险评估指标体系;利用基于 事故树的贝叶斯网络分析方法,以历年不安全事件报告为样本,正向推理预测得到不安 全事件发生概率;综合3 种重要度分析结果,辨识关键致险因素.结果表明,机长和副驾驶 技术水平、机组间搭配、与空管人员配合等5 项关键风险因素概率值超过了40%,严重影 响航班运行安全.风险推断结果与实际运行情况相符.     

复杂低空混合飞行态势安全特性研究

为揭示复杂低空混合飞行态势中蕴含的安全特性,本文从复杂低空环境特点、航空器个体异质行为特征出发,构建了低空飞行行为模型;运用Agent技术,NetLogo平台构建了复杂低空混合飞行态势仿真环境,仿真分析了飞行量、平均速度、飞行冲突等特性参数之间的相互关系及其影响规律.研究结果表明：飞行冲突随飞行量增加呈先缓慢增加,后急剧增加的趋势,随平均速度急速递增趋势,当飞行量达到80架次、平均速度约300km/h时,低空飞行态势安全性和效率均较高;通航活动的混合比例和冲突探测距离对复杂低空飞行态势安全性具有明显影响,当混合比为3:2:4:1,冲突探测距离为4km时,可显著提高飞行态势的安全性和稳定性.     

Mechanical Analysis of the Down-Hole String in a Deep Well

In a deep well, under high pressure and temperature, the force, deformation, and movement of the downhole string are very complicated. In this paper, based on the analysis of the working environment and load properties of the down-hole string in deep wells, the factors of high temperature, high pressure, and the complex structure of wells have been taken into consideration. The loads of the down-hole string, stability, back buckle configuration, dynamic characteristics, mechanical strength, and deformation have been systematically studied. On this basis, mechanical models of a down-hole string under different conditions have been established and software for aiding analysis has been developed. By using this software, deep well strings under different construction parameters can be simulated and analyzed, providing a theoretical basis and method for down-hole string assembly, as well as string down-hole construction and operation.     

基于空管指挥的飞机节油措施分析

燃油价格的不断攀升给航空公司的运营带来压力,如何节油已成为业界最为关注的问题。分析飞机的耗油特点,探讨如何发挥空管的独特作用和优势,通过采用RNAV／RNP等新技术并实施RVSM,制定相应的措施,控制飞机在运行中的燃油消耗,帮助航空公司降低成本,达到节油目的。     

Identification of serum biomarkers for diagnosing stage I lung adenocarcinoma by MALDI-TOF mass spectrometry

Objectire To identify specific biomarkers that could improve early diagnsis of lung adenuearcinoma using matrix-assisted laser desorptian/ionization (MALDI) technology. Methods Serum samples were isolated from 17 patients with stage I lung adenuearcinoma and 17 age- and sex-matched healthy controls, and the serum proteomic profiles were obtained by matrix-assistcd laser desorption ionization time of flight (MALDI-TOF) mass spectrometry. Results Compared with healthy control group, two highly expressed potential biomarkers were identified with the relative molecular weights of 6 631.64 Da and 4 964. 21 Da. The two best novel protein peaks were automatically chosen for the system training and the development of the constructed model. The constructed model was then used to test an independent set of masked serum samples from 15 lung adenocarcinoma patients and 22 healthy individuals. The analysis yielded a sensitivity of 93.3 %, and a specificity of 95.5 %. Conclusion These results suggest that MALDI-TOF-MS ProteinChip technology is a quick, convenient, and high-output analyzing method that is capable of selecting several relatively potential biomarkers from the serum of lung adenocarcinoma patients and may have a clinical value in the future, and will provide clues to identifying new serologic btomarkers of lung adenocarcinoma.     

The factors analysis and algorithm implementation of single-pattern matching

By studying the algorithms of single pattern matching, five factors that have effect on time complexity of the algorithm are analyzed. The five factors are: sorting the characters of pattern string in an increasing order of using frequency, utilizing already-matched pattern suffix information, utilizing already-matched pattern prefix information, utilizing the position factor which is absorbed from quick search algorithm, and utilizing the continue-skip idea which is originally proposed by this paper. Combining all the five factors, a new single pattern matching algorithm is implemented. It’s proven by the experiment that the efficiency of new algorithm is the best of all algorithms. Foundation item: the National Natural Science Foundation of China (Nos. 60502032 and 60672068)     

振弦式压力传感器在桥梁索力监测中的应用

从振弦式压力传感器的工作原理、结构特点和技术指标几个方面,系统地介绍了振弦式压力传感器在桥梁索力张拉过程中的检测原理与特点,结合具体的工程实例对这种传感器进行了研究分析,研究发现压力传感器读数仪测出的数值与张拉千斤顶的油表读数之间存在差值,结果表明：振弦式压力传感器在索力检测过程中所测出的数值是真实可靠的。     

基于有限自动机的航班计划句法检查技术研究

为了提高航班计划正确性和完整性的自动检查和分析能力,在分析航班计划编排特点的基础上,给出了基于有限自动机的航班计划句法检查技术,进行航班计划句法检查中的词法分析、语法分析和规则检查,并进行了例证分析,验证了运用不确定有限自动机进行航班计划句法检查的可行性。     

激光打点对镀锌钢板激光飞行焊的影响研究

文章以广汽菲克焊装车间为背景,介绍了激光飞行焊技术及镀锌钢板常见焊接缺陷与工艺优化措施。通过金相分析及配对T检验方法,验证预先激光打点工艺对车门激光飞行焊焊接缺陷的显著影响。试验结果表明,激光打点可以在95%置信区间减少(2.706,4.361)个焊接缺陷。T检验统计技术替代破坏性试验,通过对试验数据进行有效分析,在焊接工艺优化中得到越来越多的应用。