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Chihwa Kao 《Statistics & probability letters》1985,3(6):337-342
This paper proposes a diagnostic measure to detect outliers either in the response variable or in the design space both for Schmee-Hahn estimator and Buckley-James estimator in censored regressions. The diagnostics consists of the leverage point and standardized predicted residual. 相似文献
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The stiffness, mass and gyroscopic matrices of a rotating beam element are developed, a cubic function being used for the transverse displacement. Shear deflection is included by use of end nodal variables of shear strain, along with transverse displacement and cross-section rotation; rotatory inertia effects are included in the energy functional to provide a Timoshenko beam formulation. The gyroscopic effects for small perturbations are linearized as a skew symmetric damping matrix. The formulation is implemented by numerical integration for a linearly tapered circular beam. A technique of reduction of the shear nodal variable prior to global assembly is shown to provide little loss in accuracy with reduced system bandwidth. Numerical comparisons for three previously published beam models are included, with results presented for the case of forward and reverse precession to verify the gyroscopic effects. The utility of the element in a general program for rotor dynamics analysis is identified. 相似文献
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Electroluminescence in anthracene crystals has been systematically measured under time varying electric fields at various temperatures using a sodium electrode as the electron-injecting contact and a silver electrode as the hole-injecting contact. The results show that the electroluminescent brightness decreases with increasing frequency over the temperature range from ? 20 to 60°C; and that for a given frequency the brightness increases with increasing temperature, reaches a peak at a critical temperature, and then decreases with increasing temperature. The electroluminescence under a half-wave rectified sinusoidal a.c. field is brighter than that under a sinusoidal a.c. field of the same peak amplitude. There is a delay time between the application of the field and the appearance of electroluminescence, and this delay time decreases with increasing frequency and saturates at a value which may be associated with the transit time of the injected electrons across the specimen. All these results can be explained on the basis of the model that electroluminescence occurs when an electron space charge built up near the anode is sufficient to enhance hole injection from the anode. 相似文献
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Hsiao C. Kao 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1972,23(4):632-644
A radiating gas jet near the optically thin limit is examined. The gas is assumed to be inviscid, optically grey, and in the state of chemical equilibrium or to obey the ideal gas law. The jet is assumed to be plane-symmetric or axi-symmetric and is fully expanded. Under these conditions and by the method of quasi-one-dimensional flow, the problem is analyzed. In addition to this, numerical examples are also included to illustrate the radiative effects.
Zusammenfassung Es wird ein strahlender Gasstrahl untersucht, nahe zum optisch dünnen Grenzfall. Das Gas wird reibungsfrei, optisch grau und im chemischen Gleichgewicht (oder als ideales Gas) vorausgesetzt. Der Strahl wird eben oder axisymmetrisch angenommen und ist voll expandiert. Unter diesen Voraussetzungen und mit der Methode der fast-eindimensionalen Strömung wird das Problem analysiert. Zudem sind numerische Beispiele angegeben, um den Strahlungseffekt zu veranschaulichen.相似文献
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Bing-Xin Yang Yi-Han Kao Janos Kirz Chang-Xin Gu R.N. Bhargava D.A. Cammack R.J. Dalby 《Physics letters. A》1985,113(5):283-288
Transmission measurements of the extended X-ray absorption fine structure above the oxygen K-edge have been made by using a new scintillation detection technique. The absorption spectrum is in close resemblance with the total electron yield spectrum recorded at the same time. This new technique is of interest for studies of soft X-ray absorption spectroscopy for thin films of solid materials. 相似文献