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111.
Adaptation to the weightless state and readaptation after space flight to the 1-G environment on the ground are accompanied by various transitory symptoms of vestibular instability, kinetosis, and illusory sensations. Aside from the problem of how to treat and if possible prevent such symptoms, they offer a clue to a better understanding of normal vestibular functions. Weightlessness is a powerful new "tool" of vestibular research. Graybiel reported as early as 1952 that human subjects observed the illusion that a real target and the visual afterimage seemed to raise in the visual field during centrifugation when the subjects were looking toward the axis of rotation (oculogravic illusion). In aircraft parabolic-flight weightlessness, human subjects observed that fixed real targets appeared to have moved downward while visual afterimages appeared to have moved upward (oculoagravic illusion). It can be shown by electronystagmography as well as by a method employing double afterimages that part of this illusion is caused by eye movements that are triggered by the changing input from the otolith system. Another part of the illusion is based on a change of the subjective horizontal and must be caused by convergence of vestibular and visual impulses "behind" the eyes. This part was measured independently of the first one by using a new method. Eye movements could be prevented during these experiments by optical fixation with the right eye on a target at the end of a 24-in. long tube which was rigidly attached parallel to the longitudinal axis of an aircraft. At the same time the subject tried to line up a shorter tube, which was pivoting around his left eye, with the subjective horizon. 相似文献
112.
Kerwin JP 《Acta Astronautica》1975,2(1-2):85-87
The facts presented represent, for convenience, a composite clinical picture of the three crewmen aboard Skylab II as observed by me. 相似文献
113.
N. I. Akishev I. I. Zakirov V. A. Ivanov V. N. Paimushin M. A. Shishov 《Russian Aeronautics (Iz VUZ)》2011,54(2):115-124
The known analytical solutions of the linearized stability problems for rectangular hinged plates under the combined loading
are generalized to the similar problems for skew plates, the deformation mechanics of which is described by the equations
of the classical theory formed in the oblique Cartesian coordinates. 相似文献
114.
In this paper, we examine experimentally some devices the principle of action of which is based on using the dynamic pressure
of air extracted to engine cooling and which are meant for reducing the radial temperature gradient in GTE rotor disks. We
established that the devices equipped with the ejector channels make it possible to accelerate the process of the disk hub
heating by hot air suction from the cavity periphery towards the rotor axis of rotation. Using the data of visualization studies,
we show the possibility for efficient operation of ejector devices in the conditions of real GTE rotor circumferential velocities. 相似文献
115.
A technique of optimizing the electrode system of the differential recorder for the aircraft time-of-flight ion-marking airspeed
and aircraft angle of attack sensor by the criterion of ion-marking recording error variance minimum is considered. The technique
is based on analyzing the function of spatial distribution for the ion-marking and recorder electrode interaction field potential
and determining a point for which this function reaches the maximum slope. The relations making it possible to synthesize
the sensor electrode system by the complex criterion as a ratio of error variance to transformation channel response are obtained. 相似文献
116.
M. V. Usanin A. A. Siner A. M. Sipatov L. Yu. Gomzikov V. G. Avgustinovich 《Russian Aeronautics (Iz VUZ)》2011,54(1):34-42
The application of the low dissipative high-order accurate scheme for numerical solution of the Euler and Navier-Stokes equations
in the two-dimensional statement is considered. The scheme of calculating space derivatives is the seven-point central-difference
approximation of the fourth order with the coefficients optimized to reduce the dispersion errors. The optimized six-step
Runge-Kutta method is used for evaluating the time derivatives. By means of filtration, spurious pulsations are suppressed
and shocks are processed. The results of verifying the calculation scheme realized on the stationary problem of flow around
the model turbine blades are presented. 相似文献
117.
N. M. Bodunov 《Russian Aeronautics (Iz VUZ)》2011,54(1):89-94
A mathematical model of the process of bending and rolling the thin-walled components is presented taking into account the
geometrical nonlinearity. Also presented is the technique for calculating the setup variables of bending equipment, which
is based on reduction of the initial differential boundary-value problem to the discrete one with the use of the finite difference
method. 相似文献
118.
119.
We considered the influence of temperature on the nitric oxide emission under combustion of the near-stoichiometric mixtures
with and without water feed. We revealed the advantage of the method of fuel-water-air mixture combustion over that of the
leaned mixture combustion. 相似文献
120.
N. D. Akhmetov M. M. Gimadeev V. N. Drulis V. A. Krivosheev T. V. Rzaeva 《Russian Aeronautics (Iz VUZ)》2011,54(1):108-113
A technique for calculating the energy parameters of shock waves at electrical discharge in water is presented for the transition
region of discharge channel expansion using as the base the predetermined characteristics of discharge circuit. The technique
is based on the solution of energy transport equation that is similar in form to that of radiative transfer. The validity
of the presented approach was experimentally verified. 相似文献