The future world-wide installation of the newly developed Microwave Landing System (MLS) will permit a four-dimensional (incl. time) guidance of aircraft in the airport area with the combined advantages of safer, more...
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The future world-wide installation of the newly developed Microwave Landing System (MLS) will permit a four-dimensional (incl. time) guidance of aircraft in the airport area with the combined advantages of safer, more economical flight paths with less detrimental environmental impact such as noise nuisance. Purpose of this paper is to demonstrate that the introduction of these advanced navigation and flight guidance technologies will make it possible to compute and to apply continuously time-dependent command inputs for an aircraft in a way which will minimize the noise annoyance for the population living in the neighborhood of the airport. Factors considered in the investigations for the optimization calculations included not only the location and population density of living areas along the approach trajectory but also the effects of temperature and wind gradients on noise propagation. The results obtained for the Airport Düsseldorf-Lohausen show that, even taking into account numerous design, comfort, and safety constraints, the noise exposure for the average airport area inhabitant could be reduced by 70 % if the proposed flight trajectory management procedure would be applied.
Astrocytes from either fetal or newborn rat brain adhered preferentially to surfaces coated with active laminin. Neurites from septal neurons did not show a preference for active over inactive laminin. However, when g...
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Astrocytes from either fetal or newborn rat brain adhered preferentially to surfaces coated with active laminin. Neurites from septal neurons did not show a preference for active over inactive laminin. However, when given a choice between laminin and an astrocytic surface, septal cells preferred to extend neurites over astroglial processes. Hence, laminin paths can guide astrocyte migration, which, in turn, can guide neurite elongation.
This paper reviews the available evidence on the alleged reproductive hazards of VDUs. It concludes that it is unlikely that any threat is posed by irradiation. Poor design of the work station and job-related stress m...
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Neurite outgrowth is guided by narrow pathways of bioactive laminin. These pathways are created by UV light irradiation of laminin-coated coverslips masked with EM grids. Patterned outgrowth of neurites is independent...
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Neurite outgrowth is guided by narrow pathways of bioactive laminin. These pathways are created by UV light irradiation of laminin-coated coverslips masked with EM grids. Patterned outgrowth of neurites is independent of gross mechanical guidance and guidance caused by substrate limitation. Cells [chicken embryonic] on unirradiated laminin are less readily displaced by shear forces than cells on irradiated laminin. UV light alters the adhesive properties of laminin and that differential cell-substratum adhesion may guide extending neurites on the purified naturally occurring substance, laminin.
A stochastic pursuit-evasion differential game involving two players, E and P, moving in the plane is considered. It is assumed that player E (the evader) has complete observation of the position and velocity of playe...
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A stochastic pursuit-evasion differential game involving two players, E and P, moving in the plane is considered. It is assumed that player E (the evader) has complete observation of the position and velocity of player P, whereas player P (the pursuer) can measure the distanced (P, E) between P and E but receives noise-corrupted measurements of the bearing β of E from P. Three cases are dealt with: (a) using the noise-corrupted measurements of β, player P applies the proportional navigation guidance law; (b) P has complete observation ofd (P, E) and β (this case is treated for the sake of completeness); (c) using the noise-corrupted measurements of β, P applies an erroneous line-of sight guidance law. For each of the cases, sufficient conditions on optimal strategies are derived. In each of the cases, these conditions require the solution of a nonlinear partial differential equation on a in ℝ2. Finally, optimal strategies are computed by solving the corresponding equations numerically.
An approach to the guidance and control design for the near-planet leg of the interplanetary mission is discussed. The duration of communication session between the landing and orbital modules is one of the most essen...
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An approach to the guidance and control design for the near-planet leg of the interplanetary mission is discussed. The duration of communication session between the landing and orbital modules is one of the most essential quality criteria. Various perturbations and restri ctions are considered. Some results of the “Venera” mission are presented.
Suggests that parents and teachers use understanding, honest communication, reasonable and consistent limits, and respect to positively guide the thinking and behavior of young children. Presents specific techniques a...
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Suggests that parents and teachers use understanding, honest communication, reasonable and consistent limits, and respect to positively guide the thinking and behavior of young children. Presents specific techniques and examples. (SJL)
The purpose of the paper is to report the impact of the guidance Information System, a computerized career information system, on the program and management of human service agencies during the second phase of field t...
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With the development of low loss single mode optical fiber waveguides, it is possible to construct a gyroscope using optical fibers. The configuration is a multi-turn Sagnac interferometer. Light from an external sour...
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With the development of low loss single mode optical fiber waveguides, it is possible to construct a gyroscope using optical fibers. The configuration is a multi-turn Sagnac interferometer. Light from an external source is split and injected into the fiber ends, travels in clockwise and counterclockwise directions and is recombined to form interference fringes. When the coil is rotated, a phase shift is produced between the two beams causing a fringe shift ΔZ. This fringe shift is proportional to the rotation rate Ω and is given by the equation ΔZ = 4 Ω → ⋅ A → / λc , where A is the total effective area enclosed, i.e., N times the area enclosed by a single turn of the fiber where N is the number of turns. Several models using discrete components have been constructed in our laboratory using up to 1.5 kilometers of single mode optical fiber. In measurements made to date, sufficient accuracy to detect earth rotation has not been made available. The difficulty is with the phase shift measurement which requires accurate measurement of a fringe shift of 10 −4 fringes. We are investigating different forms of Sagnac interferometers to improve the accuracy. Integrated optics and modulation techniques might allow us to reach the range needed for navigation. Problems of noise peculiar to optical fibers are described.
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