A Survey on Economic-driven Evaluations of Information Technology

The economic-driven evaluation of information technology (IT) has become an important instrument in the management of IT projects. Numerous approaches have been developed to quantify the costs of an IT investment and its assumed profit, to evaluate its impact on business process performance, and to analyze the role of IT regarding the achievement of enterprise objectives. This paper discusses approaches for evaluating IT from an economic-driven perspective. Our comparison is based on a framework distinguishing between classification criteria and evaluation criteria. The former allow for the categorization of evaluation approaches based on their similarities and differences. The latter, by contrast, represent attributes that allow to evaluate the discussed approaches. Finally, we give an example of a typical economic-driven IT evaluation

Habitat Associations of Catshark Egg Cases (Chondrichthyes: Carcharhiniformes: Pentanchidae) from the U.S. Pacific Coast

Many marine species select sites for reproduction based on habitat suitability, environmental tolerances, and oceanographic conditions, in order to enhance development or survival of their offspring. For many species living in the deep sea, it is unknown which factors influence this aspect of the reproductive process. In this study, the occurrence and influences of oviposition site selection were determined for the brown catshark, Apristurus brunneus, and filetail catshark, Parmaturus xaniurus, in the greater Monterey Bay region, providing novel insights into specific habitat preferences and depth distributions. Video footage from the Monterey Bay Aquarium Research Institute (MBARI), and the National Oceanographic and Atmospheric Administration’s Southwest Fisheries Science Center Fisheries Ecology Division (NOAA-SWFSC-FED) was utilized to predict suitable oviposition habitat using MaxEnt presence-only modeling, identify attachment substrates and faunal associations using qualitative observations, and determine depth and habitat preferences using tests of independence and Manly’s selectivity indices. The greater Monterey Bay region was determined as a nursery for both A. brunneus and P. xaniurus on the basis of meeting all oviparous nursery qualifications: high densities of egg cases deposited in the same region, habitat was benthic, oviposition sites were continually used, and no juvenile sharks were observed in the vicinity of egg cases. Complex geographic and environmental features such as rugosity and depth were shown to influence oviposition sites of A. brunneus and P. xaniurus. An increase in rugosity indicated higher predictive habitat suitability. The primary depth range of oviposition sites for both species was 150–199 m, with relatively more A. brunneus egg cases in the 100–149 m range, and more P. xaniurus egg cases observed at deeper depths (200–300 m). Depth ranges for both species are similar and were expanded based on MBARI video observations (A. brunneus = 87–550 m, P. xaniurus = 99–524 m). Areas of greatest predicted habitat suitability were indicated on the shelf break and upper to mid slope of the Monterey Canyon and in adjacent canyons. MaxEnt model output indicated higher induration (i.e., rockier) habitat was the main driver of oviposition site selection. Structure forming marine invertebrates (SFMI) such as corals and sponges were identified as important faunal attachment structures, with egg cases of both species occurring significantly more often on sponges than other substrates. Nurseries are critically important habitat and this research is necessary for influencing habitat-based management. The vulnerability of these and other species prompts further research concerning the use of SFMI as oviparous nurseries for potential essential fish habitat (EFH) designation

Improvement of the Nutritive Value of High Tannin Sorghums for Broiler Chickens by High Moisture Storage (Reconstitution)

Grains from three high and one low tannin sorghum cultivars were treated as follows: 1) untreated, no water was added, the dry grain had an average moisture content of 8% and 2) the moisture content of the grain was raised by adding 25% (w/w) distilled water to the grain. The treated grain was then stored for 10 or 20 days with a 2% level of acetic-propionic acid mixture (60/40, v/v) added to deter fungal growth. This treated grain was used in diets during a 3-week feeding trial with broiler chickens. High moisture storage (reconstitution) of high tannin sorghums decreased their extractable tannin content. Chickens fed diets containing these treated sorghums had improved weight grains (23 to 83 g) and feed efficiencies compared to birds fed diets containing the untreated grain. Treatment of low tannin sorghum did not improve weight gains. Reconstitution of high but not low tannin sorghums improved protein digestibility (6 to 16%) and dietary metabolizable energy (.1 to .3 kcal/g) for broiler chickens. There was a highly significant cultivar effect on leg scores, but the correlation between dietary tannin content and leg scores was low (r = .10), suggesting that tannin content was not a major factor in leg abnormality incidences shown. The improvement in weight grains, feed efficiencies, and protein digestibilities at 10 and 20 days storage periods was not different (P greater than .05), indicating that the benefits of high moisture storage were already obtained by 10 days

Self-education and the problem of confirmation of professional scills

The article is devoted to the development of methodology for vocational training on the basis of the dynamic approach with the use of the Internet. The need to change the traditional method is considered from the standpoint of the new information culture.Статья посвящена построению методики профессионального обучения на основе динамического подхода с использованием сети интернет. Необходимость изменения традиционной методики рассмотрена с позиций новой информационной культур

Cascaded Parametric Amplification for Highly Efficient Terahertz Generation

A highly efficient, practical approach to high-energy terahertz (THz) generation based on spectrally cascaded optical parametric amplification (THz-COPA) is introduced. The THz wave initially generated by difference frequency generation between a strong narrowband optical pump and optical seed (0.1-10% of pump energy) kick-starts a repeated or cascaded energy down-conversion of pump photons. This helps to greatly surpass the quantum-defect efficiency and results in exponential growth of THz energy over crystal length. In cryogenically cooled periodically poled lithium niobate, energy conversion efficiencies >8% for 100 ps pulses are predicted. The calculations account for cascading effects, absorption, dispersion and laser-induced damage. Due to the coupled nonlinear interaction of multiple triplets of waves, THz-COPA exhibits physics distinct from conventional three-wave mixing parametric amplifiers. This in turn governs optimal phase-matching conditions, evolution of optical spectra as well as limitations of the nonlinear process.Comment: 5 pages, double colum

Suppression of interdiffusion in GaAs/AlGaAs quantum-well structure capped with dielectric films by deposition of gallium oxide

In this work, different dielectric caps were deposited on the GaAs/AlGaAs quantum well(QW) structures followed by rapid thermal annealing to generate different degrees of interdiffusion. Deposition of a layer of GaxOy on top of these dielectric caps resulted in significant suppression of interdiffusion. In these samples, it was found that although the deposition of GaxOy and subsequent annealing caused additional injection of Ga into the SiO₂ layer, Ga atoms were still able to outdiffuse from the GaAsQW structure during annealing, to generate excess Ga vacancies. The suppression of interdiffusion with the presence of Ga vacancies was explained by the thermal stress effect which suppressed Ga vacancydiffusion during annealing. It suggests that GaxOy may therefore be used as a mask material in conjunction with other dielectric capping layers in order to control and selectively achieve impurity-free vacancy disordering.J. Wong-Leung, P. N. K. Deenapanray, and H. H. Tan acknowledge the fellowships awarded by the Australian Research Council

Nucleosynthesis of light nuclei and hypernuclei in central Au+Au collisions at sNN\sqrt{s_{NN}}=3 GeV

We analyze the experimental data on nuclei and hypernuclei yields recently obtained by the STAR collaboration. The hybrid dynamical and statistical approaches which have been developed previously are able to describe the experimental data reasonably. We discuss the intriguing difference between the yields of normal nuclei and hypernuclei which may be related to the properties of hypermatter at subnuclear densities. Most importantly new (hyper-)nuclei could be detected via particle correlations, and such measurements are relevant to pin down the production mechanism.Comment: 7 pages, 6 figure

Colloidal hydrodynamic coupling in concentric optical vortices

Optical vortex traps created from helical modes of light can drive fluid-borne colloidal particles in circular trajectories. Concentric circulating rings of particles formed by coaxial optical vortices form a microscopic Couette cell, in which the amount of hydrodynamic drag experienced by the spheres depends on the relative sense of the rings' circulation. Tracking the particles' motions makes possible measurements of the hydrodynamic coupling between the circular particle trains and addresses recently proposed hydrodynamic instabilities for collective colloidal motions on optical vortices.Comment: 7 pages, 2 figures, submitted to Europhysics Letter