The National Space Development Agency of Japan (NASDA) has been studying an unmanned winged space vehicle. This is called HOPE, the Η-II Orbiting Plane. The development of its guidance, navigation and control system ...
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The National Space Development Agency of Japan (NASDA) has been studying an unmanned winged space vehicle. This is called HOPE, the Η-II Orbiting Plane. The development of its guidance, navigation and control system requires much more versatile technology than those of the rocket and the satellite. Because of the long operation time and high accuracy requirement, the aided navigation is required for HOPE. The tentative navigation reference configuration for each flight phase is obtained based on the navigation analysis. Aerodynamic heating in the entry phase has the great influence on the HOPE design. The preliminary entry guidance analysis is carried out and the design constraints for HOPE are clarified. This paper presents the outline of the above discussions.
The shape of pole surfaces of a magnet is directly related to the field distribution in the effective space of the magnet. An effective way to shape the magnetic field is to make necessary shimming on the pole surface...
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The shape of pole surfaces of a magnet is directly related to the field distribution in the effective space of the magnet. An effective way to shape the magnetic field is to make necessary shimming on the pole surfaces of the magnet. The expert system OPTIM for magnetic field shaping has the ability of imitating human’s thinking and shaping the field automatically, being independent of the guidance of designers, through inference, correction and optimization, on the basis of the stored knowledge related to the magnetic field shaping in the knowledge base of the syetem. OPTIM consists of two main parts.
Under the guidance of TCM theory ofchannels and collaterals,the author treated4 types of facial skin diseases withacupuncture in 129 *** are reportedas follows.
Under the guidance of TCM theory ofchannels and collaterals,the author treated4 types of facial skin diseases withacupuncture in 129 *** are reportedas follows.
An autopilot is designed using Sliding Mode Control Theory that can control the speed and heading of a full six degree of freedom, nonlinear model of the Navy's SDV Mark 9 vehicle. The control laws are based on a ...
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An autopilot is designed using Sliding Mode Control Theory that can control the speed and heading of a full six degree of freedom, nonlinear model of the Navy's SDV Mark 9 vehicle. The control laws are based on a simplified linear model that allows speed and heading to be treated as separate systems. Once control of headjng and speed is established, depth control is then achieved by a third control law. Although they are developed separately, the three individual control laws act simultaneously to provide robust control of speed, heading, and depth of the nonlinear model of the vehicle. Line of Sight guidance is used to convert the way points provided by the mission planner into commands for heading to which the autopilot responds. The performance of the autopilot is evaluated over a wide range of speeds to demonstrate its robustness. In addition, the effects of current are simulated and the autopilot is modified to compensate for the presence of a strong current.
Accurate track keeping of-auntonomous underwater vehicles is. necessary for the autonomous navigation of a vehicle through confined- spaces, and in the presence of obstacles and cross-current environments. Uncertainti...
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Accurate track keeping of-auntonomous underwater vehicles is. necessary for the autonomous navigation of a vehicle through confined- spaces, and in the presence of obstacles and cross-current environments. Uncertainties in the force coefficients and environmental disturbances, as well as the required accuracy lead to the need for a robust sliding mode control for successful vehicle operations. This thesis investigates the use of a cross track error-guidance law with a-sliding mode compensator and presents results based on computer simulations using a nonlinear dynamic model of the Swimmer Delivery Vehicle. Steady state errors and stability requirements are evaluated analytically for a given current speed-and direction, and are confirmed through numerical integrations. The use of integral control and disturbance estimation and compensation methods are developed in order to achieve the desired steady state accuracy. A leading track control monitoring technique is used to eliminate-track overshoot during turning and reducethe rudder activity. Finally, the effects of measurement noise are evaluated and guidelines are developed for suppressing them.
Cell migration and axon growth during neural development rely upon cell-cell and cell-matrix interactions mediated by surface glycoproteins. The surface glycoprotein recognized on leech neurons by monoclonal antibody ...
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Cell migration and axon growth during neural development rely upon cell-cell and cell-matrix interactions mediated by surface glycoproteins. The surface glycoprotein recognized on leech neurons by monoclonal antibody Lan3-2 has previously been implicated in the process of axon fasciculation during regeneration in adults. In adults leeches, Lan3-2 binds to a carbohydrate epitope of a 130 kD protein. The present study demonstrates that in embryos the antibody binds to the same carbohydrate epitope of glycoproteins with molecular weight of 130 kD and higher. As a first step in evaluating a possible role of the Lan3-2 glycoprotein or the cells that express it during neural development, we determined its distribution in the developing nervous system of the leech Hirudo medicinalis. In embryos, Lan3-2 epitope is expressed on fasciculated sensory afferents and it appears on the cell bodies before neurite outgrowth. The sensory fibers appear rostrally by embryonic day 10, less than halfway through development. Earlier, by 7 days of development at ***.C, Lan3-2 binds to previously undocumented cell types: (1) cells appearing along the embryonic midline and (2) a cluster of cells located at the rostral edge of the germinal plate. These cells only transiently express this antigen and are present at critical left-right and rostrocaudal boundaries during a period of cell proliferation, movement, and migration that produces the nervous system. Thus the Lan3-2 surface glycoprotein or the cells expressing it are candidates for involvement in axon fasciculation, cell migration, and directed axonal growth.
Complications related to approximately 8000 ultrasound-guided punctures performed in our institution during the last 19 years are reported. This study includes 3500 fine needle biopsies, 700 large bore needle biopsies...
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Complications related to approximately 8000 ultrasound-guided punctures performed in our institution during the last 19 years are reported. This study includes 3500 fine needle biopsies, 700 large bore needle biopsies, 2800 punctures of fluid collections using either a 1.2-mm spinal needle or a 7.5 F pigtail catheter, and 1000 percutaneous nephrostomies. The majority were abdominal punctures. The complication rate was 0.187% (0.100% to 0.0313%) and the mortality rate 0.033% (0.013% to 0.113%). Using the fine needle data exclusively, these rates were 0.200% (0.086% to 0.400%) and 0.028% (0.000% to 0.171%), respectively. The 95% confidence limits are in brackets.
Under the guidance and support of the State Bureau of Technical Supervision, the quarterly"Journal of the China Institute of Metrlogy" has, with the approval of State Commission of Scienceand Technology, off...
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Under the guidance and support of the State Bureau of Technical Supervision, the quarterly"Journal of the China Institute of Metrlogy" has, with the approval of State Commission of Scienceand Technology, officially come into being. Thanks to the hardwork and contribution of both facultymembers and research workers of the Institute, CIM is pleased to present this inaugural edition. This journal is a comprehensive and academic publication on science and technology. It consistsmainly of valuable and innovative papers as well as general reviews of current work in the fields ofmetrology, standardization, quality inspection.
BTT CLOS guidance is achieved on the basis of two identical, independent single-plane controllers in conjunction with polar conversion of the guidance commands. Design techniques studied include six methods of discret...
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The human body is an organic whole,andtherefore disease in one internal organ often af-fects *** Chinese herbal drugsare designed as required for the treatment ofvarious diseases according to principles of drugcombina...
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The human body is an organic whole,andtherefore disease in one internal organ often af-fects *** Chinese herbal drugsare designed as required for the treatment ofvarious diseases according to principles of drugcombination under the guidance of the concep-tion of the integral human body,so a compositeprescription is also an integral whole,and the inte-grity of the compound is aimed at the
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