航空领域开展的大脑研究项目

美国和欧盟宣布要在未来10年投入巨额资金开展脑科学研究。科技界一致认为，对大脑活动的深入了解有可能为信息技术的根本性改变创造条件。实际上，航空航天领域早已开展了这方面的探索，在将神经技术用于监视大脑活动方面进行了大量相关试验研究，以求进一步提高飞行员、空管员和系统操作员的工作效能。     

Research of Compound Controller for Flight Simulator with Disturbance Observer

A compound controller is proposed to alleviate the considerable chattering in output of zero phase error tracking controller (ZPETC), when the flight simulator losses command data of simulation signal. Besides, the shortcomings, caused by conventional differential methods in retrieving velocity and acceleration signals, are avoided to a certain extent. The compound controller based on disturbance observer (DOB) is composed of a feed-forward controller and a feedback controller. It estimates velocity and acceleration of unknown tracking signal, and also velocity response with an approximate method for differential. The experiments on a single-axis flight simulator show that the proposed method has strong robustness against parameter perturbations and external disturbances, owing to the introduced DOB. Compared with the scheme with ZPETC, the proposed scheme possesses more simple design and better tracking performance. Moreover, it is less sensitive to position command distortion of flight simulator.     

Research of Optical Fiber Coil Winding Model Based on Large-deformation Theory of Elasticity and Its Application

Optical fiber coil winding model is used to guide proper and high precision coil winding for fiber optic gyroscope (FOG) application. Based on the large-deformation theory of elasticity, stress analysis of optical fiber free end has been made and balance equation of infinitesimal fiber is deduced, then deformation equation is derived by substituting terminal conditions. On condition that only axial tensile force exists, approximate curve equation has been built in small angle deformation scope. The comparison of tangent point longitudinal coordinate result between theory and approximation gives constant of integration, and expression with tangent point as origin of coordinate is readjusted. Analyzing the winding parameters of an example, it is clear that the horizontal distance from the highest point of wheel to fiber tangent point has millimeter order of magnitude and significant difference with fiber tension variation, and maintains invariant when wheel radius changes. The height of tension and accurate position of tangent point are defined for proper fiber guide. For application to fiber optic gyroscope, spiral-disc winding method and nonideal deformation of straddle section are analyzed, and then spiral-disc quadrupole pattern winding method has been introduced and realized by winding system. The winding results approve that the winding model is applicable.     

债转股问题初探

债转股作为经济体制改革的一个重要探索，已经成为当今法学界和经济学界讨论的主题。作为一个新事物的出现，债转股必然会遇到一系列来自不同方向的阻碍，本文就这些困惑进行论述，阐明了债转股面临的主要问题，并提出相应的解决方案和建议。国民经济体制改革需要大胆的探索和创新，债转股就是一个很好的范例，尽管其实施过程中难免遇到一些难题，但必将取得骄人的成果。     

助人自助——心理咨询的真谛

心理咨询的真谛是助人自助，即唤起来访者的自助意识，引导他们通过自我领悟、转换视角、重拾自信及保持平衡等手段从无助走向自助。     

提高大学生读写能力之策略

本文着重论述了加强语言基础训练和培养语篇阅读能力是提高大学生读写能力的有效途径。指出两者是相互促进、相辅相成的的关系。同时，就如何提高大学生的读写能力提出了一些方法和策略。     

Modified Frequency Scaling Algorithm for FMCW SAR Data Processing

This paper presents a modified frequency scaling algorithm for frequency modulated continuous wave synthetic aperture radar （FMCW SAR） data processing. The relative motion between radar and target in FMCW SAR during reception and between transmission and reception will introduce serious dilation in the received signal. The dilation can cause serious distortions in the reconstructed images using conventional signal processing methods. The received signal is derived and the received signal in range-Doppler domain is given. The relation between the phase resulting from antenna motion and the azimuth frequency is analyzed. The modified frequency scaling algorithm is proposed to process the received signal with serious dilation. The algorithm can effectively eliminate the impact of the dilation. The algorithm performances are shown by the simulation results.     

Space Science & Technology in China: A Roadmap to 2050

<正>In October 2007, the Chinese Academy of Sciences (CAS) initiated a project entitled "Roadmapfor Strategic Research in Key Fields of Science and Technology in China through 2050". The project was