a generalized heckman model is used for the joint modeling of longitudinal continuousresponses and dropout in order to see the influence of a small perturbation of the elements of thecovariance structure on displacement of the likelihood. the perturbation from random dropout in thedirection of informative dropout is considered for mastitis data.

in the present work a modified in-tube solid phase microextraction technique followed by gas chromatography-mass spectrometry (gc-ms) has been applied for determination of water odorants. geosmin, 2-methyl isoborneol, 2-isopropyl-3-methoxy pyrazine, 2-isobutyl-3-methoxy pyrazine and 2,4,6-trichloroanisol are of the most important odorants which have been studied. in the described method, analyt...

In blending problems there are typically specification constraints that limit the content of various properties of the blend that it acquires from the ingredients to certain maximum or minimum percentages of the total blend. For sake of linearity, these constraints are commonly included in the problem in a way that precludes direct sensitivity analysis with respect to changes in these percentag...

We assume we have solved the problems (P) and (D), and that we have an optimal basis B ⊆ {1, 2, . . . , n}. Sensitivity analysis then refers to using to the basis B to solve a modified version (P’) and (D’) of the problems (P) and (D) from modified data A, b and c (whenever this information is useful). This is best done by example. Note that, if the optimal basic matrix AB remains unchanged, th...

a modified electrode was prepared by modification of the carbon paste electrode (cpe) with graphene nano-sheets. the fabricated modified electrode exhibited an electrocatalytic activity toward gallic acid (ga) oxidation because of good conductivity, low electron transfer resistance and catalytic effect. the graphene modified cpe had a lower overvoltage and enhanced electrical current respect to...

osmotic dehydration, as a minimal processing method, has found increasingly wide prospects during the past few decades. this process involves mass transfer which is commonly modeled by applications of different procedures, mostly based on fick's law. in this research, we approached the modeling process by first obtaining experimental measurement of potato’s solid gain, water loss and moisture c...

A new voltammetric sensor for determination of uric acid (UA) by Cuppercomplex- multiwalled carbon nanotube (Cu-complex-CNT) nanocomposite modifiedcarbon paste electrode (CPE) is reported. The electrocatalytic behavior of theCu-complex-CNT nanocomposite modified CPE was studied in pH 2.0 phosphatebuffer solution by chronoamperometry (CA) and cyclic voltammetry (CV) in th...

The contrast sensitivity test has been used to examine vision in different clinical circumstances. Moreover, as contrast sensitivity is affected by several ocular states, its measurement has been considered practically for monitoring and assessment of a wide range of visual functions, predicting vision related abilities, diagnosing several ophthalmic conditions, and evaluating many ocular disor...