Close circumnavigation is an important function indispensable for servicing satellites. We discuss the bielliptic yaround maneuver by impulsive thrust control for a small and low cost servicing satellite ying around a target satellite. An optimal feedback control scheme for the thrust is proposed to maintain this trajectory in the presence of disturbances. The extended Kalman lter is employed t...

1464-343X/$ see front matter 2009 Elsevier Ltd. A doi:10.1016/j.jafrearsci.2009.07.003 * Tel.: +1 573 341 4100; fax: +1 573 341 6935. E-mail address: [email protected] Deformed conglomeratic clasts exposed along the Neoproterozoic Nakasib Suture and the Oko Shear Zone are used to calculate three-dimensional (3D) tectonic strain associated with the latter to quantify strain associated with post-a...

Objectives To analyze the kinematics of cervical rotation-traction manipulation (CRTM). Methods An experimental study measuring the kinematics of CRTM was conducted. A total of 18 healthy volunteers participated in the study. A single manipulator operated the CRTM for all subjects. Motion capture technology was adopted to track the trajectory during the CRTM operation. Results The manipulat...

The Main Central Thrust shear zone is the dominant crustal thickening feature in the Himalayas, largely responsible for the extreme relief and mass wasting of the range. Along the Bhagirathi River in NW India, the Main Central Thrust is several kilometers thick and separates high-grade gneisses of the Greater Himalayan Crystallines from Lesser Himalayan metasedimentary rocks. Th-Pb ion micropro...

The Himalayan mountain range has been the locus of some of the largest continental earthquakes, including the 2015 magnitude 7.8 Gorkha earthquake. Competing hypotheses suggest that Himalayan topography is sustained and plate convergence is accommodated either predominantly on the main plate boundary fault, or more broadly across multiple smaller thrust faults. Here we use geodetic measurements...

1 Nursing School, Southwest Medical University, Jiangyang District, Luzhou, China. 2 Basic School, Guangzhou University of Chinese Medicine, University Island, Panyu District, Guangzhou, China. 3 Department of Oncology, The Affiliated Hospital of Southwest Medical University, Jiangyang District, Luzhou, China. 4 Department of Orthopedic, The Affiliated Hospital of Southwest Medical University, ...

This study evaluates and quantifies the variation in vegetation, plant nutrients, and microclimate across four topographic aspects in an Appalachian watershed (398399430N, 798459280W). The study found that the north and east aspects were 27–50% more productive than the west and southwest aspects. Species groups that showed strong aspect preference included yellow poplar (Liriodendron tulipifera...

New flight test maneuvers and analysis techniques for evaluating the dynamic response of in-flight thrust models during throttle transients have been developed and validated. The approach is based on the aircraft and engine performance relationship between thrust and drag. Two flight test maneuvers, a throttle step and a throttle frequency sweep, were developed and used in the study. Graphical ...

successful development, evaluation, and qualification of propulsion systems such as turbojet and turbofan engines and rocket motors require the measurement of the performance and reliability of these systems. thrust stands or testers are instruments for solid and liquid motors test. in this paper, a method for calculating of solid motors random vibrations effects on a thrust stand structure is ...

High thrust-to-power ratio on Hall-effect thrusters allows for more efficient thrust generation and better overall performance. It allows Hall-effect thrusters to perform more thrust-intensive maneuvers such as orbit raising, thus saving the mass of a second engine purely for those maneuvers. This paper presents the initial performance measurements of aHall-effect thruster using in-channel elec...