Management Practices and Financial Performance of Agricultural Cooperatives: A Partial Adjustment Model

This paper uses the Nerlovian partial adjustment model to test the hypothesis that the rate of a cooperative's adjustment to a desired financial position is partially determined by its management practices. The results indicate that management practices that are board responsibilities are not contributing to the speed of adjustment in reaching the desired financial performance, which is the responsibility of the board of directors. But management, when independently pursuing management's responsibility or when working with that board on shared responsibility, does contribute to the speed of adjustment toward the desired financial goal.Agribusiness,

Optical Activities as Computing Resources for Space-time Symmetries

It is known that optical activities can perform rotations. It is shown that the rotation, if modulated by attenuations, can perform symmetry operations of Wigner's little group which dictates the internal space-time symmetries of elementary particles.Comment: 13 pages, to be published in J. Mod. Optic

Certain terms relating to Islamic observances : their meanings with reference to three translations of the Qur'an and a translation of Hadith

EThOS - Electronic Theses Online ServiceGBUnited Kingdo

New type of ellipsometry in infrared spectroscopy: The double-reference method

We have developed a conceptually new type of ellipsometry which allows the determination of the complex refractive index by simultaneously measuring the unpolarized normal-incidence reflectivity relative to the vacuum and to another reference media. From these two quantities the complex optical response can be directly obtained without Kramers-Kronig transformation. Due to its transparency and large refractive index over a broad range of the spectrum, from the far-infrared to the soft ultraviolet region, diamond can be ideally used as a second reference. The experimental arrangement is rather simple compared to other ellipsometric techniques.Comment: submitted to Appl. Phys. Let

Embedded centrosymmetric multilayer stacks as complete-transmission quarter-wave and half-wave retarders under conditions of frustrated total internal reflection

A centrosymmetric multilayer stack of two transparent materials, which is embedded in a high-index prism, can function as a complete-transmission quarter-wave or half-wave retarder (QWR or HWR) under conditions of frustrated total internal reflection. The multilayer consists of a high-index center layer sandwiched between two identical low-index films with high-index–low-index bilayers repeated on both sides of the central trilayer, maintaining the symmetry of the entire stack and constituting a QWR ( Δt=90° or 270°) or HWR (Δt=180°) in transmission. A QWR design at wavelengthλ=1.55 μm is presented that employs an 11-layer stack of Si and SiO2 thin films, which is embedded in a GaP cube prism. The intensity transmittances for the p and s polarizations remain \u3e99% and Δt deviates from 90° by \u3c±3°over a 100 nm spectral bandwidth (1.5⩽λ⩽1.6 μm) , and by ⩽±7° over an internal field view of ±1°(incidence angle 44°⩽ϕ0⩽46° inside the prism). An HWR design at λ=1.55 μm employs seven layers of Si andSiO2 thin films embedded in a Si cube, has an average transmittance \u3e93% , and Δt that differs from 180° by\u3c±0.3° over a 100 nm bandwidth (1.5⩽λ⩽1.6 μm) and by \u3c±17° over an internal field view of ±1° . The sensitivity of these devices to film-thickness errors is also considered

Optical Study of the Free Carrier Response of LaTiO3/SrTiO3 Superlattices

We used infrared spectroscopic ellipsometry to investigate the electronic properties of LaTiO3/SrTiO3 superlattices (SLs). Our results indicated that, independent of the SL periodicity and individual layer-thickness, the SLs exhibited a Drude metallic response with sheet carrier density per interface ~3x10^14 cm^-2. This is probably due to the leakage of d-electrons at interfaces from the Mott insulator LaTiO3 to the band insulator SrTiO3. We observed a carrier relaxation time ~ 35 fs and mobility ~ 35 cm^2V^-1s^-1 at 10 K, and an unusual temperature dependence of carrier density that was attributed to the dielectric screening of quantum paraelectric SrTiO3.Comment: 4 pages, 4 figure

The language of Einstein spoken by optical instruments

Einstein had to learn the mathematics of Lorentz transformations in order to complete his covariant formulation of Maxwell's equations. The mathematics of Lorentz transformations, called the Lorentz group, continues playing its important role in optical sciences. It is the basic mathematical language for coherent and squeezed states. It is noted that the six-parameter Lorentz group can be represented by two-by-two matrices. Since the beam transfer matrices in ray optics is largely based on two-by-two matrices or $ABCD$ matrices, the Lorentz group is bound to be the basic language for ray optics, including polarization optics, interferometers, lens optics, multilayer optics, and the Poincar\'e sphere. Because the group of Lorentz transformations and ray optics are based on the same two-by-two matrix formalism, ray optics can perform mathematical operations which correspond to transformations in special relativity. It is shown, in particular, that one-lens optics provides a mathematical basis for unifying the internal space-time symmetries of massive and massless particles in the Lorentz-covariant world.Comment: LaTex 8 pages, presented at the 10th International Conference on Quantum Optics (Minsk, Belarus, May-June 2004), to be published in the proceeding

Fast and optimal broad-band Stokes/Mueller polarimeter design by the use of a genetic algorithm

A fast multichannel Stokes/Mueller polarimeter with no mechanically moving parts has been designed to have close to optimal performance from 430-2000 nm by applying a genetic algorithm. Stokes (Mueller) polarimeters are characterized by their ability to analyze the full Stokes (Mueller) vector (matrix) of the incident light. This ability is characterized by the condition number, $\kappa$, which directly influences the measurement noise in polarimetric measurements. Due to the spectral dependence of the retardance in birefringent materials, it is not trivial to design a polarimeter using dispersive components. We present here both a method to do this optimization using a genetic algorithm, as well as simulation results. Our results include fast, broad-band polarimeter designs for spectrographic use, based on 2 and 3 Ferroelectric Liquid Crystals, whose material properties are taken from measured values. The results promise to reduce the measurement noise significantly over previous designs, up to a factor of 4.5 for a Mueller polarimeter, in addition to extending the spectral range.Comment: 10 pages, 6 figures, submitted to Optics Expres