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81.
Neha Gupta Irfan Ali Abdul Bari 《Journal of Mathematical Modelling and Algorithms》2014,13(3):341-352
When we are dealing with multivariate problem then we need an allocation which is optimal for all the characteristics in some sense because the individual optimum allocations usually differ widely unless the characteristics are highly correlated. So an allocation called “Compromise allocation” is to be worked out suggested by Cochran. When auxiliary information is also available, it is customary to use it to increase the precision of the estimates. Moreover, for practical implementation of an allocation, we need integer values of the sample sizes. In the present paper the problem is to determine the integer optimum compromise allocation when the population means of various characteristics are of interest and auxiliary information is available for the separate and combined ratio and regression estimates. This paper considers the optimum compromise allocation in multivariate stratified sampling with non-linear objective function and probabilistic non-linear cost constraint. The probabilistic non-linear cost constraint is converted into equivalent deterministic one by using Chance Constrained programming. The formulated multi-objective nonlinear programming problem is solved by Fuzzy Goal programming approach and Chebyshev approximation. Numerical illustration is also given to show the practical utility of the approaches. 相似文献
82.
Simultaneous wavelength conversion of multichannel polarization shift keying (PolSK) signal using four-wave-mixing in highly non-linear fiber is demonstrated. In the proposed wavelength converter, the wavelengths of four 10-Gb/s polarization shift keying channels are simultaneously converted without any performance degradation for the converted channels. We successfully achieved high conversion performances for all the converted channels even though the input PolSK channels have different delay time and state of polarization. 相似文献
83.
Malcıoğlu OB Calzolari A Gebauer R Varsano D Baroni S 《Journal of the American Chemical Society》2011,133(39):15425-15433
The optical properties of the flavylium state of the cyanin dye are simulated numerically by combining Car-Parrinello molecular dynamics and linear-response time-dependent density functional theory calculations. The spectrum of the dye calculated in the gas phase is characterized by two peaks in the yellow and in the blue (green and violet), using a GGA-PBE (hybrid-B3LYP) DFT functional, which would bring about a greenish (bright orange) color incompatible with the dark purple hue observed in nature. Describing the effect of the water solvent through a polarizable continuum model does not modify qualitatively the resulting picture. An explicit simulation of both solvent and thermal effects using ab initio molecular dynamics results instead in a spectrum that is compatible with the observed coloration. This result is analyzed in terms of the spectroscopic effects of the molecular distortions induced by thermal fluctuations. 相似文献
84.
A barrier film is a fundamental component of the fast growing organic electronic device industry that is necessary to sustain long‐term stability. The barrier film prevents the permeation of environmental moisture and oxygen into the organic electronic device. Superior barrier property is the most crucial characteristic of a barrier film, in addition to a high refractive index. A high‐refractive‐index barrier film has the potential to reduce the refractive‐index mismatch between a device and a protective film, consequently, reducing the energy costs by increasing the light output. In this work, six epoxy and phenoxy resin composite compositions are synthesized separately, each with a different cross‐linker. POL‐TE1/PET and POL‐HD1/PET films show enhanced refractive indexes of 1.726 (at 750 nm) and 1.721 (at 500 nm), allowing only 71.7% and 70.4% permeation, respectively, compared to those of POL/PET, while exhibiting more than 80% transparency and excellent properties. The films are fabricated using a straightforward process, from a solution, at low temperature and under atmospheric conditions, using an applicator and bar coating. 相似文献
85.
Bari Rozana Denton Aric A. Fondren Zachary T. McKenna Gregory B. Simon Sindee L. 《Journal of Thermal Analysis and Calorimetry》2020,140(6):2649-2655
Journal of Thermal Analysis and Calorimetry - The thermal properties of CL-20 explosive in the bulk and confined in controlled pore glass matrices to nanoscale dimensions were studied using dynamic... 相似文献
86.
Azetidine-2,3-diones can be conveniently synthesized by mild hydrolysis of the product of the reaction between α-phenylthio-β-lactams and sulfuryl chloride. 相似文献
87.
Samuel Levine Christopher W. Outhwaite Lutful B. Bhuiyan 《Journal of Electroanalytical Chemistry》1981,123(1):105-119
A comparison is made of present-day statistical mechanical theories of the diffuse part of the electric double layer in aqueous 1-1 electrolyte at a charged plane interface. These theories fall into three categories: (1) the modified Poisson-Boltzmann equation (MPB) based on the Kirkwood-Loeb charging of an ion; (2) the adaption to the electric double layer of the Bogoliubov-Born-Green-Yvon (BBGY) hierarchy of integral equations; (3) the use of the Ornstein-Zernike equation (OZ) for the direct correlation functions of the pair interfacial plane wall-molecular particle, as derived by Henderson, Abraham and Barker (HAB). The HAB-OZ equation is used in conjunction with the mean spherical approximation (MSA) or hypernetted chain approximation (HNC). All the theories make use of the primitive model of the bulk electrolyte, so that inhomogeneity of the dielectric permittivity next to the plane wall is neglected. Except perhaps for a variation of the BBGY theory, which uses a closure based on electrical neutrality, all the theories predict oscillatory behaviour in potential distribution as a function of distance at the higher electrolyte concentrations. The HAB-OZ model has the defect that electrostatic imaging is not consistent with the assumptions of central forces and pair-wise additivity of ionic interactions. It is found that the MPB provides the best overall agreement with Monte Carlo calculations. 相似文献
88.
89.
We consider the notion ofp, δ-absolute continuity for functions of several variables introduced in [2] and we investigate the validity of some basic properties
that are shared by absolutely continuous functions in the sense of Maly. We introduce the classδ−BV
loc
p
(Ω, ℝ
m
) and we give a characterization of the functions belonging to this class.
Supported by MURST of Italy. 相似文献
90.
Judith M. Wingate Bari Hoffman Ruddy Donna S. Lundy Jeffrey Lehman Roy Casiano Savita P. Collins Gayle E. Woodson Christine Sapienza 《Journal of voice》2005,19(1):124-131
Adductor spasmodic dysphonia (ADSD) adversely affects a speaker's ability to effectively communicate. For many individuals suffering with ADSD, botulinum toxin (Botox) is the chosen treatment to remediate the symptoms. Although Botox's effects on symptom remediation have been examined before, patient perception of improvement post-Botox has been examined less frequently. Further, no studies have addressed the symptomatic changes in older adults that occur after Botox treatment. The Voice Handicap Index (VHI) was used as the instrument to assess older patient's (>65 years) perception of how ADSD impacts certain areas of their life pre- and post-Botox injection. The outcome of the VHI was related to a clinical judgment of voice severity. Participants also completed the Social Readjustment Rating Scale (SRRS) to examine overall stress level, and the outcome of the SRRS was correlated to postinjection VHI scores. Results indicated no significant correlation between VHI scores and voice severity or SRRS ratings. The current study suggests further study of voice outcomes with older adults with ADSD is needed. 相似文献