J. F. Lemaire,and K. I. Gringauz,with contributions from D. L. Carpenter and V. Bassolo,The Earth's Plasmasphere

Space Science Reviews -     

Concepts of turbulence and C.F.D. applications

The article's main theme is the ‘turbulence modelling’ used in present days' computational schemes. This modelling is an effort to account for the influence of turbulent motion on diffusion processes, and reflects our efforts to bridge what is generally recognized as the ‘closure gap’, i.e. to replace a needed phenomenological relation(s) with hypotheses of some kind. In this way one tries to remedy our lack of knowledge of turbulent motion. For that purpose a number of ideas and concepts over the past 60 years is mentioned and their incorporation in numerical analysis is discussed. The main emphasis is placed on the physical concepts and their consequences.     

Comments on `Existence and uniqueness of GPS solutions' by J.S.Abel and J.W. Chaffee

The commenter points out that a direct Global Positioning System (GPS) algorithm together with discussions on the existence and uniqueness of the solution appeared in his paper (J. Guidance, Control, and Dynamics, vol.9, p.715-17, Nov./Dec. 1986). Since the GPS solution is reduced to solving a quadratic equation, the existence and uniqueness can be easily tested. J.S. Abel and J.W. Chaffee, in the above-titled paper (ibid., vol.26, no.6, p.748-53, Sept. 1990), show that the GPS solution problem is similar to the hyperbolic-fix problem. The commenter notes that it can be inferred from his later work (ibid., vol.26. no.5, p.748-53, Sept. 1990) that the two solutions exist if and only if the four GPS satellites are coplanar, in which case the two solutions are mirror-symmetric with respect to the GPS plane     

美国军用航空装备维修保障体制

军用航空装备，是军用航空器及其各种装置、设备的统称，通常是指飞机、直升机、航空发动机、航空弹药、航空电子设备以及航空仪表、电气设备等。军用航空装备维修保障，是为保持、恢复和改善军用航空装备技术状况所采取的技术和管理措施。维修保障是保持军用航空装备持续作战能力的关键环节，是打赢信息化条件下的高技术局部战争的重要支撑。早在1907年，美国陆军就组建了陆军通信兵航空兵科，经过一百多年的发展，美国已形成了军地融合、覆盖陆海（含海军陆战队）空军的军用航空装备维修保障体制。通过对其进行分析研究，有利于为深化我国军用航空装备维修保障体制改革提供参考和借鉴。     

G. Burkhardt,U. Esser,H. Hefele,I. Heinrich,W. Hofmann,V. R. Matas,L. D. Schmadel,R. Wielen,and G. Zech (eds.), Astronomy and Astrophysics Abstrats

Space Science Reviews -     

F. P. Pijpers,J. Christensen-Dalsgaard,and C. S. Rosenthal (eds.), SCORe '96: Solar Convection and Oscillations and their Relationship

Space Science Reviews -     

H. J. Habing and H. J. G. L. M. Lamers (eds.), Planetary Nebulae,IAU Symposium 180

Space Science Reviews -     

C. M. Carollo,H. C. Ferguson and R. F. G. Wyse (eds.), The Formation of Galactic Bulges

Space Science Reviews -     

奥巴马政府上台后美军装备采办管理与改革

采办管理改革是推动采办管理制度有效运行的重要保证。奥巴马政府上台以来,面对装备采办领域严重的"拖进度、降指标、涨费用"问题,不断推进采办管理改革,要求军方加强对采办过程的审查监督力度,颁布了《武器系统采办改革法》,并酝酿对信息系统采办的管理体制与运行程序实施改革。     

U.S. Army battery needs-present and future

The purpose of this paper is to describe the needs of the U.S. Army for silent portable power sources, both in the near and longer term future. As a means of doing this, the programs of the Power Sources Division of the Army Research Laboratory are discussed. In carrying out these programs, the personnel of the Power Sources Division work closely with the Battery Management Office of the Army Materiel Command, which is located in the Logistics and Readiness Directorate of the Communication-Electronics Command (CECOM). We are also closely integrated with the Army Research Office, and the fuel cell personnel of the CECOM Research Development and Engineering Center (RDEC), and the battery personnel of the RDECs for the Tank and Automotive Command and the Missile Command. The six program areas discussed in which the Power Sources Division is engaged are: primary batteries, rechargeable batteries, reserve/fuze batteries, pulse batteries and capacitors, fuel cells, and thermophotovoltaic power generation     

Henny J.G.L.M. Lamers and Jopseph P. Cassinelli (eds.), Introduction to Stellar Winds

Space Science Reviews -     

J. A. Docobo,A. Elipe,and H. A. McAlister (eds.), Visual Double Stars: Formation,Dynamics and Evolutionary Trucks

Space Science Reviews -     

J.-L. Starck,F. Murtagh,and A. Bijaoui,Image Processing and Data Analysis,The Multiscale Approach

Space Science Reviews -