飞机防治小麦叶枯性病害研究

China is a big agricultural country. If she can raise the yield of grain through aviation, it would be of great significance to her national economy. This kind of researches developed by the writer of this article has already gained much economic benefits, with its value popularizing to the whole country. The departments of general aviation are worthwhile to use for reference in the practical work.     

Ameco-Beijing——a big name in a booming market

Catching up with the fast development of worldeconomy,China pulled up its bamboo curtain andsponsored an even more faster revolution of economytill 1978.The cooperation with German Lufthansa isone of China’s major steps to upgrade its civil avia-tion industry.The Aircraft Maintenance＆EngineeringCo.-Beijing(Ameco-Binjing),a partnership start-ed in 1989 by Air China and German Lufthansa is thelargest and the most powerful civil aircraft mainte-nance company in China.     

Trajectory reshaping based guidance with impact time and angle constraints

This study presents a novel impact time and angle constrained guidance law for homing missiles. The guidance law is first developed with the prior-assumption of a stationary target, which is followed by the practical extension to a maneuvering target scenario. To derive the closed-form guidance law, the trajectory reshaping technique is utilized and it results in defining a specific poly-nomial function with two unknown coefficients. These coefficients are determined to satisfy the impact time and angle constraints as well as the zero miss distance. Furthermore, the proposed guidance law has three additional guidance gains as design parameters which make it possible to adjust the guided trajectory according to the operational conditions and missile’s capability. Numerical simulations are presented to validate the effectiveness of the proposed guidance law. ? 2016 Chinese Society of Aeronautics and Astronautics. Production and hosting by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).     

Act to Reverse Our Fate

The world aviation industry fell in straits because of the global economic downturn andterrorist activities in recent years. In comparison, the Chinese civil aviation industry, is stillable to keep stable development. This year, however, the abrupt break of SARS has hit theindustry severely. The epidemic is unprecedentedly serious in terms of its duration, scope andconsequences. According to our information, some airlines have reduced two thirds of theircapacities, the loss of the industry i…     

Assembly Variation Identification of High Pressure Spool by Response Surface Based Model Updating Using IV-optimal Designs

This article, in order to improve the assembly of the high-pressure spool, presents an assembly variation identification method achieved by response surface method (RSM)-based model updating using IV-optimal designs. The method involves screening out non-relevant assembly parameters using IV-optimal designs and the preload of the joints is chosen as the input features and modal frequency is the only response feature. Emphasis is placed on the construction of response surface models including the interactions between the bolted joints by which the non-linear relationship between the assembly variation caused by the changes of preload and the output frequency variation is established. By achieving an optimal process of selected variables in the model, assembly variation can be identified. With a case study of the laboratory bolted disks as an example, the proposed method is verified and it gives enough accuracy in variation identification. It has been observed that the first-order response surface models considering the interactions between the bolted joints based on the IV-optimal criterion are adequate for assembly purposes.     

First Shanghai International Aviation Symposium Held

Shanghai held its first international aviation symposium at its Portman Ritz-Carlton from April 28 to 30 in order to promote the sustainable development of the civil aviation industry in East China and the Yangtze Delta. The forum was also considered as an accelerating effort to build Shanghai into an international air hub. CAAC Minister Yang Yuanyuan and Shanghai Mayor Han Zheng delivered opening speeches.Yang said: "Priority should be given to the human spirit when we step up effort to build the city into an air hub. We aim to let more common people benefit from the development of civil aviation."     

决策者寄语（英文）

<正>The program"Made in China 2025"was first menlioned by Premier Li Keqiang at the annual session of the National People's Congress.China will upgrade its manufactuing power in the next 10 years by focusing on 10 industrial sectors,aeiospace and aviation equipment is being one of them.Jandvile Coromant is always attaching importance to the aeiospace industry and     

Pico-satellite Autonomous Navigation with Magnetometer and Sun Sensor Data

This article presents a near-Earth satellite orbit estimation method for pico-satellite applications with light-weight and low-power requirements. The method provides orbit information autonomously from magnetometer and sun sensor, with an extended Kalman filter (EKF). Real-time position/velocity parameters are estimated with attitude independently from two quantities: the measured magnitude of the Earth’s magnetic field, and the measured dot product of the magnetic field vector and the sun vector. To guarantee the filter’s effectiveness, it is recommended that the sun sensor should at least have the same level of accuracy as magnetometer. Furthermore, to reduce filter’s computation expense, simplification methods in EKF’s Jacobian calculations are introduced and testified, and a polynomial model for fast magnetic field calculation is developed. With these methods, 50% of the computation expense in dynamic model propagation and 80% of the computation burden in measurement model calculation can be reduced. Tested with simulation data and compared with original magnetometer-only methods, filter achieves faster convergence and higher accuracy by 75% and 30% respectively, and the suggested simplification methods are proved to be harmless to filter’s estimation performance.     

Secondary instability of separated shear layers

The process through which a laminar flow undergoes transition to turbulence is of great fundamental and practical interest. Such a process is hugely complex as there are many diverse routes for a laminar flow to become turbulent flow. The transition process is usually initiated by flow instabilities—a primary instability stage followed by a secondary instability stage. This forms a rational framework for the early stage of a transition process and it is crucially important to understand the physics of instabilities leading to turbulence. This article reviews the results of studies on secondary instability of separated shear layers in separation bubbles and summaries the current status of our understanding in this area.     

High-temperature gas effects on aerodynamic characteristics of waverider

This paper focuses on the analysis of high-temperature effect on a conical waverider and it is a typical configuration of near space vehicles. Two different gas models are used in the numerical simulations, namely the thermochemical non-equilibrium and perfect gas models. The non-equilibrium flow simulations are conducted with the usage of the parallel non-equilibrium program developed by the authors while the perfect gas flow simulations are carried out with the commercial software Fluent. The non-equilibrium code is validated with experimental results and grid sensitivity analysis is performed as well. Then, numerical simulations of the flow around the conical waverider with the two gas models are conducted. In the results, differences in the flow structures as well as aerodynamic performances of the conical waverider are compared. It is found that the thermochemical non-equilibrium effect is significant mainly near the windward boundary layer at the tail of the waverider, and the non-equilibrium influence makes the pressure center move forward to about 0.57% of the whole craft’s length at the altitude of 60 km.     

航空高科技企业经营决策者胜任特征推导模型实证研究

 遵循社会科学的实证研究方法，在前期行为事件访谈基础上形成问题，自编胜任特征行为测量问卷，对104名航空高科技企业经营决策者进行测试，研究其胜任特征内涵，进而建立推导模型。研究结果表明，可以基于以下5个因子建立中国航空高科技企业经营决策者胜任特征推导模型，包括成就与创新、责任与激情、战略与执行、合作与沟通、正直与诚信。该推导模型对航空高科技企业乃至军工制造业经营决策者的选拔、领导力提升、评价与激励等人力资源管理方面具有理论指导与技术支持的价值。该研究期望通过对实际情况的研究，抽取供管理实践借鉴的特征模型，提升管理实践的科学性、规范性。     

跨国创新系统:中国民航企业国际化经营战略

创新已成为国际竞争的决定性因素。跨国公司的对外直接投资使东道国有了更便捷的学习机会。中国作为发展中国家,为实现“赶上”或“替代”战略,需要更有效的创新理论与政策工具。民航业自身具有国际化、全球化的特点。中国民航运输企业需要建立和发展其技术创新、组织创新、市场创新能力,有效利用各种资源,保持可持续发展及核心竞争力。     

飞行阶段预防性维修风险识别和控制方法

运用头脑风暴法和层次分析法,对飞行四个阶段中航空维修出现的预防性维修风险进行识别和控制,并以机械日机务准备活动为案例进行分析,经实践验证,此方法可消除或降低飞行阶段航空维修过程中出现的预防性维修风险发生的概率,为其它机型开展此项工作奠定基础。     

中国通用航空发展研究

对通用航空发达国家美国的通用航空现状和发展趋势做了研究,分析了美国通用航空高度发达的主要原因,给出了美国通用航空发达对中国通用航空发展的启示;讨论了中国通用航空极度落后与制约发展的因素;阐述了大力发展中国通用航空的必要性;并对中国通用航空发展前景做了展望。     

中国民航运输业缝隙市场竞争博弈分析

基于缝隙市场理论和博弈理论，新建了缝隙市场竞争博弈模型，分析了中国民航运输业在规制放松过程中不同市场结构下新航空公司和原在位航空公司之间的市场竞争行为，证明了新航空公司运用缝隙市场竞争策略既可以较大可能地避免在位者的挤压，也能最大程度地获得规制者的优先容纳。缝隙市场竞争策略是新进入者参与市场博弈的占优策略。     

民航企业大文化战略及经济学意义

中国民航市场化道路的历程非常短暂，面对WTO这一全新的环境与条件，必须从企业大文化战略的高度，调整自身与整个世界发展背景的关系。提出民航企业大文化战略不仅限于重视企业文化建设，而是在此基础上从整体、长远、综合的角度考虑发展目标、实现目标的可能性及具体途径。阐述了实施大企业文化战略的3个原因，即不同文化类型的综合化，消费水平的高层次化，社会文化的企业化。     

大数据在航空系统的研究现状与发展趋势

针对大数据在航空系统中的应用问题,阐述了学术界与航空工业界在航空大数据采集传输、分析技术及可视化等方面的研究现状。提出了航空大数据平台基础架构,对目前推出的几款航空大数据分析平台结合优化运营、优化维护、降低成本、降低风险等方面的需求进行了评述。指出大数据在航空系统中的应用还存在着理念、方法、技术、人等方面的挑战,并相应地提出大数据组织专门化、处理方法混合化、分析平台柔性化及跨界合作深入化等发展趋势。     

Air transport system sensibilities

The growth of air traffic will make it one of the more significant sources of exhaust emissions in the future. This must be countered by the aviation industry with new, environmentally adapted aircraft technology, as well as air traffic management controlled by environmental concern. The issue of the day is to show how to influence the air transport system to make it sustainable. This article describes work intended to develop a broad conceptual framework for evaluating and encouraging appropriate economic, regulatory, operational and technical strategies.     

An air-rail inter-modal strategy for aircraft recovery

It is common that airlines encounter a disruption of a flight schedule, which is mainly caused by resource shortages. In case of a disruption, subject to scarce resources, most of airlines lose flexibility of performing aircraft recovery on the basis of business interest priorities and need to delay, swap, and cancel flights. This paper proposes an air-rail inter-modal strategy to incorporate a High-Speed Rail(HSR) transport mode into an aviation network for aircraft recovery. The air-rail inter...     

中国大型飞机发动机研制中的关键技术

简要论述了中国研制大涵道航空发动机的部分关键技术,以期对中国具有自主知识产权的大涵道比发动机研制工作提供参考。