双下侧定几何二元混压式进气道的流场特征和气动性能分析

针对一种冲压发动机用双下侧布局二元混压式进气道,利用经过试验验证的数值方法分析其流场特征和气动性能。研究结果表明:1)在高于起动马赫数2.25下一定反压范围内,由于气动喉道的出现使结尾激波系可以停留在收缩通道内;2)随着来流马赫数的增大,进气道的总压恢复系数下降;而流量系数先上升,当激波贴口后基本保持不变;3)在一定迎角范围内,进气道的总压恢复系数和流量系数提高,但当迎角增大至进气道不起动时,随着迎角的增大,进气道的总压恢复系数和流量系数基本不变;4)随着侧滑角的增大,两侧进气道总压恢复系数均是下降的。

超混杂复合材料及Ti/CFRP层间混杂复合材料

从当前航空航天技术对结构材料的力学性能及其综合性能的要求出发，介绍了超混杂复合材料的概念、研究目的和研究结果，并与国内外其他复合材料相比较，指出Ti／CFRP层间混杂复合材料是一种性能优良的新型结构材料。

Evaluation of AMSR-E——Derived Soil Moisture over Northern China

In this study,the authors evaluated two re-motely sensed surface soil moisture datasets derived from the Advanced Microwave Scanning Radiometer of the Earth Observing System (AMSR-E) over northern China.The soil moisture datasets were derived from algorithms developed by the National Snow and Ice Data Center (NSIDC) and jointly developed by the Vrije Universiteit Amsterdam and NASA Goddard Space Flight Center (VUA-NASA).The NSIDC and VUA-NASA products were compared to in situ soil moisture data from nine enhanced coordinated observation stations.The VUA-NASA dataset presented a strong correlation with top layer in situ soil moisture observations,and the correla-tion coefficients ranged from 0.34 to 0.73 (p<0.01).The correlation coefficients decreased as the observed soil layer depth increased.The correlation coefficients be-tween the NSIDC retrievals and the top layer in situ ob-servations were between 0.10 and 0.62 (p<0.01).Fur-thermore,VUA-NASA soil moisture variations agreed well with in situ soil moisture dynamics and responded sensitively to precipitation events.In contrast,the NSIDC dataset failed to capture signals of soil moisture dynamics.The analyses demonstrated that the VUA-NASA product was capable of representing soil moisture conditions over northern China.

Orbital Milling Hole of Aerospace Al-Alloy with Big Pitch

To improve the processing efficiency and the quality of orbital milling hole of aerospace Al-alloy, the big-pitch influence on cutting force and hole quality was studied experimentally. First, a program based on horizontal lathe was proposed based on kinematics analysis of orbital milling. Then, the cutting force at different stages and the hole quality with different pitches were measured. Results show that the axial force and radial force increase with the pitch amplification during orbital milling. However, the axial force in the orbital milling hole is about 8—10 times smaller than that in the conventional drilling. The diameter error of milling hole is 48—93 μm, and the surface roughness of milling hole is 1.2—1.7 μm. Finally, an orbital milling device with big pitch was designed.

Novel Adaptive Simulated Annealing Algorithm for Constrained Multi-Objective Optimization

In recent years, sinmlated annealing algo-rithms have been extensively developed and uti-lized to solve nmlti-objective optimization problems. In order to obtain better optimization perfonmnce, this paper proposes a Novel Adaptive Simulated Annealing （NASA） algorithm for constrained multi-objective optimization based on Archived Multi-objective Simulated Annealing （AMOSA）. For han-dling multi-objective, NASA makes improverrents in three aspects： sub-iteration search, sub-archive and adaptive search, which effectively strengthen the stability and efficiency of the algorithnm For handling constraints, NASA introduces corresponding solution acceptance criterion. Furtherrrore, NASA has also been applied to optimize TD-LTE network perform-ance by adjusting antenna paranleters; it can achieve better extension and convergence than AMOSA, NS-GAII and MOPSO. Analytical studies and simulations indicate that the proposed NASA algorithm can play an important role in improving multi-objective optimi-zation performance.

Atmospheric correction of ocean color imagery over turbid coastal waters using active and passive remote sensing

This paper demonstrates an atmospheric correction method to process MODIS/Aqua (Moderate-resolution Imaging Spectroradiometer) ocean color imagery over turbid coastal waters with the aid of concurrent CALIOP (Cloud-Aerosol LIdar with Orthogonal Polarization) aerosol data, assuming that there exists "nonturbid" water in the study area where MODIS aerosol optical properties can be retrieved accurately. Aerosol properties from CALIOP measurements were obtained and related to those from MODIS. This relationship, combined with CALIOP aerosol data, was extended to turbid water to derive MODIS aerosol properties, where atmospheric correction using MODIS data alone often fails. By combining MODIS and CALIOP data, aerosol signals were separated from the total signals at the satellite level, and water-leaving radiances in turbid waters were subsequently derived. This method was tested on several MODIS/Aqua ocean color images over South China turbid waters. Comparison with field data shows that this method was effective in reducing the errors in the retrieved water-leaving radiance values to some extent. In the Zhujiang (Pearl) River Estuary, this method did not overestimate the aerosol effects as severely, and provided far fewer negative water-leaving radiance values than the NASA (National Aeronautics and Space Administration) default methods that used MODIS data alone.

Annual and Interannual Variability of Scatterometer Ocean Surface Wind over the South China Sea

To investigate the annual and interaunual variability of ocean surface wind over the South China Sea （SCS）, the vector empirical orthogonal function （VEOF） method and the Hilbert-Huang transform （HHT） method were employed to analyze a set of combined satellite scatterometer wind data during the period from December 1992 to October 2009. The merged wind data were generated from European Remote Sensing Satellite （ERS）-1/2 Scatterometer, NASA Scatterometer （NSCAT） and NASA＇s Quick Scatterometer （QuikSCAT） wind products. The first VEOF mode corresponds to a winter-summer mode which accounts for 87.3% of the total variance and represents the East Asian monsoon features. The second mode of VEOF corresponds to a spring-autumn oscil- lation which accounts for 8.3% of the total variance. To analyze the interannual variability, the annual signal was removed from the wind data set and the VEOFs of the residuals were calculated. The temporal mode of the ftrst intcrannual VEOF is correlated with the Southern Oscillation Index （SOI） with a four-month lag. The second temporal interannual VEOF mode is correlated with the SOI with no time lag. The time series of the two interannual VEOFs were decomposed using the HI-IT method and the results also show a correlation between the interannual variability and El Nino-Southern Oscillation （ENSO） events.

Simultaneous Measurements of Rainfall Intensity, Low Energy Neutrons and Gamma Radiation in Sao Jose Dos Campos, SP, Brazil

The article aims to study the possible correlation between the presence and intensity of rainfall X- and T-radiation and low energy neutrons at one specific location in S[io Jos6 dos Campos, SP, Brazil. Monitoring of these parameters was carried out from end February to half of June 2013 just in Physics Department of ITA （Technological Institute of Aeronautics）. By correlating the data of measurements of intensity of X and ）,-radiations with the rainfall it has been found that this meteorological parameter had a significant influence on the background of these radiation profile. A possible reason for this fact is associated with the presence of radon gas in the environment that is dragged to the surface during the occurrences of local rainfall. In relation neutrons, it was possible to note that the rainfall has small influence on this parameter measures.

Vibration Suppression Analysis for Supporter with Constrained Layer Damping

By analyzing the correlation between modal calculations and modal experiments of a typical supporter, an effective finite element analysis( FEA)model of the actual aerospace supporter is created. According to the analysis of constrained viscoelastic damping, the strategies of PVC have been worked out, and the correlation between modal calculations and modal experiments of the supporter has also been computed, and then, an experiment has been designed based on the calculation results. The results of experiments verify that the PVC strategy can effectively suppress vibration.

Losses Calculation of an Aerospace Retraction Wheel Motor with Regarding to Electromagnetic-Field Analysis Investigation

A 3-D FEA （finite element analysis） transient and steady-state design proposal for high-speed with Nd-Fe-Br （reversible） magnets in aerospace application will be examined under design considerations of n = 12,000 rpm, short-duty, sinusoidal drive, low cogging, high efficiency at peak torque, and etc. for an ARWM （aerospace retraction wheel motor）. In construction, the PMs （permanent magnets） fixed on the rotor core which is surface-mOunted magnets retained by a carbon-fiber bandage. Redundant windings, resistant to fault propagation have accounted. Besides, an axial water-jacket housing without end-cap cooling has involved. All performed characteristic performances of the correlated ARWM will verify by comparison through 2-D and 3-D FEA results. In this paper, design process has dealing with determination of various kinds of losses such as electromagnetic and mechanical losses. In terms of both classified losses, copper, stator back iron, stator tooth, PM, rotor back iron, air-friction and sleeve losses were calculated. The 3-D end-winding effects were included in the modeled ARWM by the authors.

Experimental Tests of the Operating Conditions of a Micro Gas Turbine Device

The aim of this work is to analyze the performance of a commercial micro gas turbine, focusing on the analysis of the fuel consumption and the outlet compressor and turbine temperature at various rpm, and to evaluate and compare the efficiency of the device. A test bench has been assembled with the available equipment in the laboratory of the department of mechanical and aerospace engineering in Roma. By using the software supplied by the manufacturer, the evaluation of the operating performance of the device at different speeds has been performed, obtaining all the values of interest.

Validation of Land Surface Temperature Derived from 37-GHz AMSR-E over Northern China

A validation study of land surface temperature (LST) obtained from the Ka band (37 GHz) vertically polarized brightness temperature over northern China is presented.The remotely sensed LST derived jointly by the Vrije Universiteit Amsterdam and the NASA Goddard Space Flight Center (VUA-NASA) from the Advanced Microwave Scanning Radiometer-Earth Observing System (AMSR-E) were compared to the daily in-situ top soil temperature/infrared surface temperature observations from eleven/three Enhanced Coordinated Observation stations in arid and semi-arid regions of northern China.The VUA-NASA LST from the descending path exhibited a stronger correspondence to the in-situ infrared surface temperature than soil temperature observations,whereas correlations (R 2) of the latter ranged from 0.41 to 0.86.Meanwhile,the ascending overpass LST was generally warmer than the in-situ soil temperature observations at all stations,and the correlation (R 2) was between 0.07 and 0.72.Furthermore,the correlation of the descending path was generally greater than that of the ascending path at the same station.The descending path VUA-NASA LST was sensitive to precipitation and presented good agreement with ground temperature dynamics.The analyses demonstrated that the descending overpass LST was reliable to reflect reasonable patterns of temperature dynamics for land surface temperature in the region.

China-Venezuela Space Cooperation Benefits and Review

For the last 10 years,the Venezuelan aerospace industry has been constantly growing,and it is to be expected to continue in the same way in the future.China and its space industry,as the main partner for most of the ongoing Venezuelan space projects from their beginning,has been an important player in their development and may continue acting as one of the most important partners not only for the Venezuelan aerospace industry but also for other Latin-American countries' aerospace industries.ABAE(Bolivarian Agency for Space Activities) together with the related Chinese aerospace companies,with the guidance and help of CGWIC,has been constantly improving its cooperation methods,regarding technical work flows as well as management activities,especially for the latest's space projects under development,namely the CIDE(Venezuelan Design,Assembly,Integration and Testing Center) and VRSS-2(Venezuelan Remote Sensing Satellite-2) programs.Provided that there is a deeper and stronger cooperation in the future,partnership and friendship of the different scientists,experts and leaders from the space sectors of both countries,will be improved and strengthened for the development of both nations social welfare.

Sensible Heating over the Tibetan Plateau Linked to the Onset of Asian Monsoon

Land surface heating of the Tibetan Plateau (TP) plays an important role in the Asian Monsoon system. In this study, the interannual variability of the sensible heat flux over the TP and its connection with the summer monsoon intensity and onset date was examined based on the newly released land "reanalysis" data, produced by NASA Global Land Data Assimilation System. Although correlation analyses don't show a significant relevance to the summer monsoon intensity, the interannual anomalies in sensible heating near the south flank of the TP indicate a weak reversal in the relationship with the onset date of the West Pacific East Asian monsoon. A diagnostic study shows that above (below) normal sensible heating over the south flake of the TP will lead to rapid (slow) warming of the upper air column over the TP and early (later) reversal of (overturn) the meridional temperature gradient and the vertical wind shear. This will further lead to an earlier (later) onset of the Asian Monsoon.

Could the 2012 Drought in Central US Have Been Anticipated？-A Review of NASA Working Group Research

This paper summarizes research related to the 2012 record the NEWS （NASA （National Aeronautics and Space Administration） drought in the central United States conducted by members of Energy and Water cycle Study） Working Group. Past drought patterns were analyzed for signal coherency with latest drought and the contribution of long-term trends in the Great Plains low-level jet, an important regional circulation feature of the spring rainy season in the Great Plains. Long-term changes in the seasonal transition from rainy spring into dry summer were also examined. Potential external forcing from radiative processes, soil-air interactions, and ocean teleconnections were assessed as contributors to the intensity of the drought. The atmospheric Rossby wave activity was found to be a potential source of predictability for the onset of drought. A probabilistic model was introduced and evaluated for its performance in predicting drought recovery in the Great Plains.

Value Creation for the After-Sales Services： Organizational and Strategic Perspectives

As a part of the product development process, the after-sales services are not only a source of innovation, but also they benefit from value creation through new managerial methodologies for the achievement of competitive advantage and customer satisfaction. The objective of the paper is to further understand value creation for the after-sales services. We present the case of the creation of a new business for the after-sales services for the entrance into a new market. The new business is created by two gurus in the aerospace industry. A typology of guidelines is derived, based on organizational and strategic perspectives, for the after-sales services value creation and the guidelines for the creation of a new business as well as for the entrance of into a new market are presented.

Animation of Chinese Characters： Evolution of Shapes and Styles

Hanzi （Chinese characters） has a long history and affluent contents. To promote the popularity of historical and cultural knowledge of Chinese characters, an online program has been launched by Beihang University and Beijing Normal University to explain Chinese characters＇ original meanings and evolution processes with vivid and expressive animation videos. Currently, More than 1,000 videos can be accessed through the website “http：//www.chinesecharacter.org/”. Besides these online resources, a human-computer interaction system is also proposed to simulate clerical changes of Chinese characters through computer morphing technology. What we want is to make the teaching and learning of Chinese characters more reasonable, more easily understandable and more interesting.

Performance evaluation of operational atmospheric correction algorithms over the East China Seas

To acquire high-quality operational data products for Chinese in-orbit and scheduled ocean color sensors, the performances of two operational atmospheric correction(AC) algorithms(ESA MEGS 7.4.1 and NASA Sea DAS 6.1) were evaluated over the East China Seas(ECS) using MERIS data. The spectral remote sensing reflectance R_(rs)(λ), aerosol optical thickness(AOT), and ?ngstr?m exponent(α) retrieved using the two algorithms were validated using in situ measurements obtained between May 2002 and October 2009. Match-ups of R_(rs), AOT, and α between the in situ and MERIS data were obtained through strict exclusion criteria. Statistical analysis of R_(rs)(λ) showed a mean percentage difference(MPD) of 9%–13% in the 490–560 nm spectral range, and significant overestimation was observed at 413 nm(MPD>72%). The AOTs were overestimated(MPD>32%), and although the ESA algorithm outperformed the NASA algorithm in the blue-green bands, the situation was reversed in the red-near-infrared bands. The value of α was obviously underestimated by the ESA algorithm(MPD=41%) but not by the NASA algorithm(MPD=35%). To clarify why the NASA algorithm performed better in the retrieval of α, scatter plots of the α single scattering albedo(SSA) density were prepared. These α-SSA density scatter plots showed that the applicability of the aerosol models used by the NASA algorithm over the ECS is better than that used by the ESA algorithm, although neither aerosol model is suitable for the ECS region. The results of this study provide a reference to both data users and data agencies regarding the use of operational data products and the investigation into the improvement of current AC schemes over the ECS.

Diagnosis and Treatment Value of Ultrasound for Hepatobiliary and Pancreatic Disease

As an innovative technology, ultrasound has been applied to agriculture, medical, military, aerospace, machinery and other fields widely, as well as the medical industry, such as ultrasound diagnosis, ultrasound therapy. Ultrasonic technology has many advantages, and it certainly will promote the progress in medical area as a new method.

Structural Aerospace Composite/Metallic Samples under Fatigue Loads： Experimental Activity on Three Case Studies

The use of composite materials in aerospace engineering is ever increasing. Properties such as low weight, high performance, high stiffness and the ability for it to be tailored specifically for different structural uses has increased its importance in recent years. Specific experimental/numerical activities were developed in the last decade at the aerospace department of Polito and are under consideration in recent years regarding the analysis of fatigue behavior of composite/metallic structural samples under cyclic loading condition. A review of the main significant results connected to three case-studies is presented in the paper. The first is related to the definition and analysis of innovative joint for composite high aspect ratio aircraft structures. The modular design oriented to limit component dimensions for transportability requires the presence of a removable joints able to overcome the typical low bearing failure level of composite pin-loaded joint under static and fatigue loading distribution according to airworthiness requirements. The static experiments demonstrate the consistency of the proposed advanced joint configuration that postpones the joint failure to high load level according to the structural requirements. The cyclic loading phase takes as reference point the failure load of the initial configuration and defines a loading cycle with a maximum higher than the failure load of the initial configuration. The fatigue behavior of the advanced joint also demonstrates a substantial consistency with expected duration of 1 e6 cycles as required by the structural design for operating reasons. Specific indication on fatigue limit with respect to critical amplitude is reported. The second is related to the presence of specific damaged situation in thin-walled fiat/stiffened composite plate. Stiffened configurations are frequently used to increase buckling load level. Unexpected events on solid/stiffened composite panels can introduce a certain level of damage, typically delamination, that can cause reduction in buckling design level and reduction in global strength. The presence of cyclic load and fatigue effect can have an important consequence on damage propagation and structural integrity. The damaged area determined by the skin-stiffener de-bonding of a certain dimension is investigated under static compression and cyclic compression. Local buckling of damaged area is determined and pointed out by tests in uniaxial compression. The experimental static behavior points out the presence of a snap-effect during loading and un-loading. Fatigue loading configuration is applied in the range of post-critical local configuration considered as the most effective situation. Preliminary fatigue results are presented and discussed. The third is related to preliminary investigation on the effect of fatigue life reduction of 2024 AI alloy in corrosive （exfoliation） environment. The effect of corrosion is taken into consideration introducing specific concentration factors into the life estimation relationship. Differences between fatigue in prior corroded specimens and fatigue in presence of corrosive environment are emphasized. No crack propagation is considered. Related concentration factors are derived and compared by the few experimental results in order to define some guidelines for design process and to improve aircraft better evaluation of component structural integrity in operative situations. A preliminary approach is presented in the paper in order to correctly identify the contribution of corrosive environment in coupled fatigue loading phase. The results are discussed and future improvements are suggested.