This paper describes China’s HQ 61 surface-to-air missile system, especially the main tactical and technical performances, missile aerodynamic configuration, propulsion system, warhead, guidance and electric system. ...
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This paper describes China’s HQ 61 surface-to-air missile system, especially the main tactical and technical performances, missile aerodynamic configuration, propulsion system, warhead, guidance and electric system. The paper also briefs the weapon’s launching facilities and operation process.
November 11,1992 was the thir-ty fifth anniversary of China A-cademy of Launch Vehicle Technol-ogy(CALT),which grows out ofthe First Branch of the Fifth Acade-my under the Ministry of *** Xuesen was itsfirst president...
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November 11,1992 was the thir-ty fifth anniversary of China A-cademy of Launch Vehicle Technol-ogy(CALT),which grows out ofthe First Branch of the Fifth Acade-my under the Ministry of *** Xuesen was itsfirst president. Since its establishment in 1957,under the guidance of the principleof relying on our own efforts,striking for external assistance andmaking good use of science andtechnology achieved by the devel-oped countries,CALT has been de-
In vivo, intracellular recordings of mammalian brain stem motoneurones, followed by peroxidase staining and tridimensional reconstruction, suggest that the shape of the dendritic tree plays an important role in the pr...
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In vivo, intracellular recordings of mammalian brain stem motoneurones, followed by peroxidase staining and tridimensional reconstruction, suggest that the shape of the dendritic tree plays an important role in the processing of neural information. To test this hypothesis attempts were made to guide, in culture, the growth of neuritic branches of neurones dissociated from the hypoglossal nucleus of rat brain stem. This was performed using topographical and adhesive microstructures which were designed to control the shape of the neuritic tree. guidance of the neuritic process can be observed with small grooves engraved on quartz and plastic substrates, and simple shapes with few processes and bifurcations on each neurite could be obtained using adhesive microstructures. These procedures, which allow the shape of a neurone to be controlled, are very promising in the study, by means of classical electrophysiological methods as well as optical recordings, of the involvement of dendritic architecture in the processing of neural information.
The guidance and leakage properties of single and coupled dielectric strip waveguides are analyzed using the dyadic Green's function and integral equation formulation. Galerkin's method is used to solve the in...
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The guidance and leakage properties of single and coupled dielectric strip waveguides are analyzed using the dyadic Green's function and integral equation formulation. Galerkin's method is used to solve the integral equation for the dispersion relation. The effects of the geometrical and the electrical parameters on the dispersion relation are investigated. A method for predicting the occurrence of leakage is proposed. The properties of the even and the odd leaky modes are also investigated. Results are compared with previous analysis and are shown to be in good agreement.
A novel technique for the remote guidance of fast mobile robots has been developed and implemented. With this method, the mobile robot follows the general direction prescribed by an operator. However, if the robot enc...
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A novel technique for the remote guidance of fast mobile robots has been developed and implemented. With this method, the mobile robot follows the general direction prescribed by an operator. However, if the robot encounters an obstacle, it autonomously avoids collision with that obstacle while trying to match the prescribed direction as closely as possible. This novel implementation of shared control is completely transparent and transfers control between teleoperation and autonomous obstacle avoidance gradually. The method, called teleautonomous operation, allows the operator to steer vehicles and robots at high speeds and in cluttered environments, even without visual contact. Teleautonomous operation is based on the virtual force field (VFF) method, which was developed for autonomous obstacle avoidance. The VFF method is especially suited to the accommodation of inaccurate sensor data and sensor fusion, and allows the mobile robot to travel quickly without stopping for obstacles.
There are two guiding modes of the Hubble Space Telescope used for the acquisition of astronomical data by one of its six scientific instruments. The nominally more precise one is called Fine Lock and the other is kno...
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This paper provides a summary of the regulatory background for the U.S. geologic repository program, describing the history of the congressional actions that established the program and the allocation of responsibilit...
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This paper provides a summary of the regulatory background for the U.S. geologic repository program, describing the history of the congressional actions that established the program and the allocation of responsibilities within the program. The current status of actions by the U.S. Department of Energy (DOE) to investigate a potential repository site, located at Yucca Mountain in Nye County, Nevada, is then reviewed. The U.S. Nuclear Regulatory Commission has provided guidance to the DOE for characterizing potential repository sites, and the DOE's approach to implementing that guidance is described. One of the purposes of intensive characterization of a potential repository site is to reduce uncertainties about key aspects of the site that are relevant to protection of public health and safety. However, the link between measurable site characteristics and demonstrations of compliance with regulatory criteria promulgated by the responsible federal agencies are often complex. A discussion of types of uncertainties points out that the potential licensee (DOE) and the regulator (NRC) may have differing views of the nature and importance of uncertainties.
Scientists at the Texas Accelerator Center and Texas A&M University are developing a new technology for high-speed maglev transportation. The technology is based on self-shielded superferric magnets which provide ...
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Scientists at the Texas Accelerator Center and Texas A&M University are developing a new technology for high-speed maglev transportation. The technology is based on self-shielded superferric magnets which provide guidance and levitation above 50 mph. A linear motor is used for propulsion. The levitation and guidance superconducting magnets are distributed along the entire length of the cars. The superferric magnet shields the fringe field within the car to less than 5 gauss. Magnetic details and initial calculations of dynamics are presented below.
The outgrowth of corticospinal tract axons in rat spinal cord primarily occurs during the first postnatal week. Axons originating from a group of layer V pyramidal cell bodies situated in the anterior part of the cere...
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The outgrowth of corticospinal tract axons in rat spinal cord primarily occurs during the first postnatal week. Axons originating from a group of layer V pyramidal cell bodies situated in the anterior part of the cerebral sensorimotor cortex project mainly to the cervical gray matter (Joosten et al., Dev. Brain Res., 36 (1987) 121-130). By co-culturing explants of the anterior part of the sensorimotor cortex and of cervical spinal gray matter in 3-D collagen gels, a target-specific directional growth of cortical axons towards the cervical spinal gray explant could be demonstrated. After retrograde filling with the fluorescent tracer 1,1-dioctadecyl-3,3,3',3'-tetramethyl indocarbocyanine perchlorate (DiI), in vivo as well as in vitro, most of the DiI-labelled cortical neurons were located in layer V of the cortical explant, and were characterized by a pyramidal shape. These data suggest that the cervical spinal gray matter target area becomes innervated by corticospinal axons through the release of a diffusible chemotropic factor.
Sensory neurons of Hirudo medicinalis were cultivated on patterns of extracellular matrix (ECM) protein which were prepared by UV irradiation using copper grid masks. The relation of the patterns and of the outgrowth ...
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Sensory neurons of Hirudo medicinalis were cultivated on patterns of extracellular matrix (ECM) protein which were prepared by UV irradiation using copper grid masks. The relation of the patterns and of the outgrowth of neurites was observed by scanning electronmicroscopy after gold decoration. The neurites were guided by narrow (10-mu-M) lanes of ECM protein. Branching of neurites was induced by branched lanes. Bent neurites were pulled off bent lanes at some distance behind the growth cone such that their length was reduced. Regularly spaced sites of adhesion became visible which remained connected to the neurites by extended filaments.
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