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1.
Omer Ozturk Steven N. MacEachern 《Annals of the Institute of Statistical Mathematics》2004,56(4):701-720
We develop a method of randomizing units to treatments that relies on subjective judgement or on possible coarse modeling
to produce restrictions on the randomization. The procedure thus fits within the general framework of ranked set sampling.
However, instead of selecting a single unit from each set for full measurement, all units within a set are used. The units
within a set are assigned to different treatments. Such an assignment translates the positive dependence among units within
a set into a reduction in variation of contrasting features of the treatments.
A test for treatment versus control comparison, with controlled familywise error rate, is developed along with the associated
confidence intervals. The new procedure is shown to be superior to corresponding procedures based on completely randomized
or ranked set sample designs. The superiority appears both in asymptotic relative efficiency and in power for finite sample
sizes. Importantly, this test does not rely on perfect rankings; rather, the information in the data on the quality of rankings
is exploited to maintain the level of the test when rankings are imperfect. The asymptotic relative efficiency of the test
is not affected by estimation of the quality of rankings, and the finite sample performance is only mildly affected. 相似文献
2.
5,6-O-Cyclohexylidene-1-amino-3-azahexane (L) is synthesized from 1-chloro-2,3-O-cyclohexylidenepropane, which is prepared by the reaction between epichlorohydrin and cyclohexanone. In this reaction, BF3 · OEt2 is used as a catalyst. Complexes of Co(II), Ni(II) and Cu(II) acetates with this ligand are prepared. The structures of the ligand and its complexes are proposed based on elemental analysis, IR and UV-VIS spectroscopy, magnetic susceptibility, conductometry, and 1H and 13C NMR spectroscopy. 相似文献
3.
Turan Ozturk Andrey S. Klymchenko Sule Oncul Sule Taskiran F. Betul Kaynak Alexander P. Demchenko 《Tetrahedron》2007,63(41):10290-10299
Nine new 3-hydroxyflavone derivatives as fluorescent molecular sensors having two well-separated emission bands were synthesized. These sensors can occupy well-determined locations and orientations in macromolecular ensembles, such as micelles due to their finely-tuned designs. These polarity-sensitive dyes can incorporate into the anhydrous hydrophobic core of aqueous micelles. 相似文献
4.
Post-implantation annealing of N-implanted 304 stainless steel at 400 °C has been investigated by conversion electron Mössbauer spectroscopy, X-ray diffraction and Auger electron spectroscopy. After a 1 h anneal, the near complete dissolution of the as-implanted Fe2N-like nitride phase results in a 9 at.% N fcc solid-solution phase. After the final anneal (64 h), N has diffused to a depth of about 2 m and remains in solid solution with an average content of 4 at.%. An average N diffusion coefficient at 400 °C is estimated to be 10-12-10-14 cm2/s, depending on anneal time, too small to explain the deep penetration observed in high-flux, high-dose N-implanted stainless steel. The present results provide additional evidence for beam controlled N migration where Cr plays an important role. 相似文献
5.
Acta Mathematicae Applicatae Sinica, English Series - In present note, we apply the Leibniz formula with the nabla operator in discrete fractional calculus (DFC) due to obtain the discrete... 相似文献
6.
Acta Mathematicae Applicatae Sinica, English Series - In present note, we apply the Leibniz formula with the nabla operator in discrete fractional calculus (DFC) due to obtain the discrete... 相似文献
7.
E. Ozturk 《The European Physical Journal B - Condensed Matter and Complex Systems》2010,75(2):197-203
The laser field dependence of the linear and nonlinear intersubband optical absorption in a graded quantum well (GQW) under an applied electric field is investigated in the effective mass approximation. In our calculations, the position and the magnitude of the linear and total absorption coefficients depend on the laser parameter and electric field strength. The resonant peak of total absorption coefficient can be bleached at sufficiently high incident optical intensities. Such a dependence of the exciting optical intensity on the external field strengths in GQWs can be very useful for several potential device applications. 相似文献
8.
The intersubband absorption in square and graded quantum wells under a laser field is calculated within the framework of the effective mass approximation. We conclude that, for quantum wells with different shapes, the laser field amplitude induces an important effect on the electronic and optical properties of the semiconductor structure. This gives a new degree of freedom in various device applications based on the intersubband transition of electrons. 相似文献
9.
10.
N,N′‐Diiodo‐N,N′‐1,2‐ethandiylbis(p‐toluene sulfonamide) (NIBTS) is a good and new reagent for synthesis of 2‐arylbenzimidazoles and 2‐arylbenzothiazoles at room temperature under solvent‐free condition with good to high yield. Absence of solvent, short reaction times, non‐corrosive, operational simplicity and environmentally friendliness are the main advantages of this procedure. 相似文献