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51.
This paper examines the relative efficiency of alternative methods of producing care for the developmentally disabled. A linear programming framework is used to construct a production frontier which allows measurement of relative efficiency among institutions in the sample. Tests are performed to detect influential observations in the data which might result from measurement error which could distort the efficiency measures. Different types of institutions are compared in terms of average efficiency. Policy implications of the analysis are discussed in the concluding section. 相似文献
52.
V.?V.?BryukhanovEmail author A.?M.?Ivanov I.?G.?Samusev 《Journal of Applied Spectroscopy》2005,72(6):804-808
The processes of homo-and hetero-triplet—triplet annihilation (TTA) of Bengali rose on the spongy silicon surface have been
investigated. It has been found that upon pulse photoexcitation on the silica surface photophysical processes involving the
triplet states of monomers and their associates can develop. It has been shown that the processes of hetero-TTA are inhibited
due to the decomposition of associates under the influence of hexane molecules in the molecular clusters of the dye adsorbates.
__________
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 72, No. 6, pp. 734–737, November–December, 2005. 相似文献
53.
Xu Xiaoyong Zheng Guoguang Wang Qing-an 《Journal of Quantitative Spectroscopy & Radiative Transfer》2005,92(1):61-72
This paper experimentally and theoretically examines the scattering properties of simulated non-spherical hydrometeors including water oblates, ice oblates and ice sphere-cone-oblates, in terms of the backscattering cross-section and the differential reflectivity. The experimental measurements of the backscattering cross-sections of non-spherical hydrometeor samples were performed in the Electromagnetic Scattering Laboratory of China National Space Industrial Corporation. Meanwhile, the backscattering cross-sections have been computed with the transition (T) matrix method. The theoretical results are compared with the experimental data, showing that the calculations are consistent with the observations in general. Experimental and theoretical analyses indicate that the backscattering cross-section of non-spherical particles increases as the particle size parameter increases, and fluctuates when the sizes are larger under the effect of resonance scattering. Differential reflectivity ZDR of water oblates in natural rainfall is always greater than 0 dB whereas ZDR of hailstones may be negative. There is a good linear relationship between differential reflectivity and aspect ratio of a particle. These derivations agree with the literature and can be used to identify the presence of hail particles and distinguish between plate-type and columnar-type hydrometeors. In this study, the measuring experiment and the T-matrix method calculations for the scattering of simulated raindrop and ice particles are also briefly described. 相似文献
54.
The intermolecular vibrational energy transfer from triplet molecules of benzophenone and anthraquinone to H2O molecules has been investigated. To determine the rates of establishment of vibrational (V-V) and thermal (V-T) equilibrium in a vibrational quasi-continuum of mixed singlet-triplet levels, the dependences of the decay rates and intensities of the fast and slow components of delayed fluorescence on the H2O vapor pressure have been investigated. For V-V relaxation, the efficiencies 1 and the mean energies E transferred per collision in mixtures with H2O and other polyatomic foreign gases have been compared. It has been established that the efficiencies 1 for quasi-resonant vibrational energy transfer (V-V) from benzophenone and anthraquinone to H2O are an order of magnitude lower than the gas-kinetic ones and lower than those obtained under the same experimental conditions for such foreign gases as C5H12, SF6, and CCl4, and decrease with increasing temperature in the 433–513 K range. It has been concluded that the mechanism of V-V relaxation in mixtures with H2O are determined by long-range attractive forces. In mixtures with H2O, no acceleration of V-T relaxation due to the formation of hydrogen bonds has been revealed. The low-efficiency thermalization process (V-T relaxation) is controlled by short-range repulsive forces, and the differences between the intensities 2 for mixtures of benzophenone and anthraquinone with H2O and other polyatomic gases are determined by the change in the reduced mass of interacting molecules. 相似文献
55.
Fei?Zhangchfli@whu.edu.cn" title="zhangfei@.com chfli@whu.edu.cn" itemprop="email" data-track="click" data-track-action="Email author" data-track-label="">Email author Chengfang?Li Lina?Shi 《Optical and Quantum Electronics》2004,36(15):1253-1261
We study a Si-based diode with a p+nn+ structure for picosecond semiconductor closing switch and discuss the physical process, which underlies the operation principle of high-power closing switch based on a delayed breakdown diode (DBD). From the results of numerical simulations and theoretical analysis, single device has demonstrated reliable operation at 2.3 kV, 89 ps risetime, and high output dV/dt(30 kV/ns). As a contribution to the optimal design, some conclusions about trade-off are drawn by changing structure parameters and physical parameters. 相似文献
56.
Y. Rama Krishna Sarma 《Annals of the Institute of Statistical Mathematics》1987,39(1):497-512
Summary In this note some asymptotically optimum tests for testing hypotheses concerning parameters when the observations are dependent
are obtained. Test statistics based on the score functions, similar to the one proposed by Rao in the case when the observations
are i.i.d. are proposed. Asymptotically UMP tests for one sided hypotheses against one sided alternatives and asymptotically
UMP unbiased test for a simple hypothesis against two sided alternatives are derived. In the multiparameter case tests for
simple hypotheses that have asymptotically best constant power on some family of surfaces in the parameter space are derived. 相似文献
57.
Summary The experimental techniques developed to build a sensitive gravitational wave antenna can find application in many different
fields of research. In the present paper we discuss briefly two experiments that we are developing in the Istituto Fisica
Spazio Interplanetario of C.N.R. More precisely, a noncryogenic gravity gradiometer to be flown on the subsatellite of the
TSS and a cryogenic force sensor which will be used to verify some recent results on the interaction of neutrino with matter
are described.
To speed up publication the proofs were not sent to the authors and were superivised by the Scientific Committee. 相似文献
58.
《TOP》1986,1(1):127-138
Summary Many estimating procedures are carried out with incomplete data by means of different types of EM algorithms. They allow us
to obtain maximum likelihood parameter estimates in classical inference and also estimates based on the posterior mode in
Bayesian inference. This paper analyzes in detail the spectral radii of the Jacobian matrices algorithm as a possible way
to evaluate convergence rates. The eigenvalues of such matrices are explicitly obtained in some cases and, in all of them,
a geometric convergence rate is, at least, guaranteed near the optimum. Finally, a comparison between the leading eigenvalues
of EM and direct and approximate EM-Bayes algorithms may suggest the efficiency of each case. 相似文献
59.
Sample path large and moderate deviation principles for Markov modulated risk models with delayed claims are proved by the exponential martingale method. As applications, asymptotic estimates and exponential bounds of the ruin probability are also studied. 相似文献
60.
Takaki Hayashi Nakahiro Yoshida 《Annals of the Institute of Statistical Mathematics》2008,60(2):367-406
We consider the problem of estimating the covariance of two diffusion-type processes when they are observed only at discrete
times in a nonsynchronous manner. In our previous work in 2003, we proposed a new estimator which is free of any ‘synchronization’
processing of the original data and showed that it is consistent for the true covariance of the processes as the observation
interval shrinks to zero; Hayashi and Yoshida (Bernoulli, 11, 359–379, 2005). This paper is its sequel. Specifically, it establishes asymptotic normality of the estimator in a general nonsynchronous sampling scheme. 相似文献