Experiments and numerical predictions were conducted to study heat (mass) transfer characteristics in a two-pass trapezoidal channel simulating the cooling passage of a gas turbine blade. Three different rib configurations were tested for the air entering the smaller cross section of the trapezoidal channel as well as the larger cross section of the trapezoidal channel at four different Reynolds numbers of 9,400, 16,800, 31,800, and 57,200. (+) 60º ribs, (–) 60º ribs and 60º V-shaped ribs were attached on both the top and bottom walls in parallel sequence. A naphthalene sublimation technique was used, and the heat and mass transfer analogy was applied to convert the mass transfer coefficients to heat transfer coefficients. Numerical predictions of three-dimensional flow and heat transfer also were performed for the trapezoidal channel with and without 90º ribs tested by Lee et al. (2007). Reynolds stress turbulence model (RSM) in the FLUENT CFD code was used to calculate the heat transfer coefficients and flow fields at Re = 31,800. The results showed that the combined effects of the rib angle, rib orientation, and the sharp 180° turn significantly affected the heat (mass) transfer distributions. The secondary flows induced by the sharp 180° turn and the angled or V-shaped ribs played a very prominent role in heat (mass) transfer enhancements. The heat (mass) transfer enhancements and the pressure drops across the turn for 60° V-shaped ribs had the highest values, then came the case of (+) 60° ribs, and the heat (mass) transfer enhancements and the friction factor ratios for (–) 60º ribs was the lowest. However, comparing (–) 60º ribs with the 90º ribs, (–) 60º ribs produced higher heat (mass) transfer enhancements than the 90º ribs, as results of the secondary flow induced by the (–) 60º ribs. The overall average heat (mass) transfer for the larger inlet cases was always higher than that for the smaller inlet cases in the ribbed trapezoidal channel. Considering the thermal performance comparisons of the (+) 60° ribs, the (–) 60º ribs, and 60° V-shaped ribs for the smaller inlet cases, the highest thermal performance was produced by the (–) 60º ribs, and the 60° V-shaped ribs and the (+) 60° ribs had almost the same levels of the thermal performance since the 60° V-shaped ribs produced the highest heat (mass) transfer enhancement but also produced highest pressure drops. For the larger inlet cases, the (+) 60° ribs produced the highest values, then came the case of the 60° V-shaped ribs, and the thermal performance for the (–) 60º ribs was the lowest. The Reynolds stress model (RSM) showed well flow fields and heat transfer distributions but underpredicted average Nusselt number ratios.

People in Sweden are exposed to the English language on a daily basis. This essay aims to study to what extent the mother tongue of Swedish pupils affects their writing in English in a negative way, called negative transfer. The material is based on a collection of English essays written by Swedish students, which has been searched for errors.

Although there exist some people management process models related to the education and training of software engineers, there are no process models that are adapted to specific software engineering contexts and processes. In this paper, we suggest a set of education and training activities that are applicable in the context of a handover process. We then evaluate these activities within twenty organizations. Although our results reveal great diversity of using these activities, they still show that they are realistic and appropriately mirror the industrial status within a software handover context. / <p>© 2011 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works. QC 20120223</p>

We solve the equations of radiation hydrodynamics to compute the time evolution toward one-dimensional equilibrium solutions using ageneralized Kramers opacity, κ=κ0 ρa Tb, with adjustable prefactor κ0 and exponents a and b on density ρ and temperature T, respectively. We choose our initial conditions to be isothermal and find that the early time evolution away from the isothermal state is fastest near the height where the optical depth is unity, and is slower both above and below it. In all cases where the quantity n=(3-b)/(1+a) is larger than -1, we find a nearly polytropic solution with ρ<img src="http://www.diva-portal.org/cgi-bin/mimetex.cgi?%5Cpropto" />Tn in the lower part and a nearly isothermal solution in the upper part with a radiating surface in between, where the optical depth is unity. In the lower part, the radiative diffusivity is found to be approximately constant, while in the upper optically thin part it increases linearly. Interestingly, solutions with different parameter combinations a and b that result in the same value of n are rather similar, but not identical. Increasing the prefactor increases the temperature contrast and lowers the value of the effective temperature. We find that the Péclet number based on sound speed and pressure scale height exceeds numerically manageable values of around 104 when the prefactor κ0 is chosen to be approximately six orders of magnitude below the physically correct value. In the special case where a=-1 and b=3, the value of n is undetermined and the radiative diffusivity is strictly constant everywhere. In that case we find a stratification that is approximately adiabatic. Finally, exploratory two-dimensional calculations are presented where we include turbulent values of viscosity and diffusivity and find that onset of convection occurs when these values are around 3<img src="http://www.diva-portal.org/cgi-bin/mimetex.cgi?%5Ctimes" />1013 cm2 s-1. The addition of an imposed horizontal magnetic field suppresses small-scale convection, but has not led to instability in the cases investigated so far.

During the last decade research in leadership has escalated and newleadership styles have started to prevail. This study intends to examinewhether a leaders increased level of motivation in turn can motivateemployees. A major company included all employees in a leader position inan exhaustive intervention with the purpose to increase the leaders’motivation in order for them to motivate their employees. After theintervention, which ended in spring 2012, interviews with six differentemployees at the company were made to see if their level of motivation hadincreased. The interviews were semi-structured with an interview guide as asupport for the researcher. The material is interpreted through hermeneuticmethod were the researcher uses the hermeneutic spiral to raise theunderstanding of the subject and reach validity. Through the threeinterpretations which are presented in the result the researcher found twowords which seemed to be the foundation for the concept of motivation: rolemodel and acknowledgement. The result shows that depending on what yousearch for in a leader the intervention has been either useful or useless. Theemployees who want a role model have not seen any difference in theleaders, whilst the employees who wanted more acknowledgementexperience that the leaders have changed due to the intervention. Four of thesix interviewed employees have become more motivated. For furtherresearch it would be interesting to dive into the leaders point of view, alsoresearching this topic with a Multifactor Leadership Questionnaire would beinteresting, as well as including the head office to see if the results of theintervention have fulfilled their expectations.

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No description available.

The primary focus of this dissertation is the electrochemical preparation of radical cation salts utilizing the donor o-4,4’-dimethyltetrathiafulvalene (o-Me2TTF) and spherical, tetrahedral, octahedral, bimetallic, cyanometallate, and polyoxometallate anions. Other donors, such as tetramethyl(tetraselenafulvalene) (TMTSF), tetramethyl(tetrathiafulvalene) (TMTTF), bis(ethylenedithio)tetrathiafulvalene (BEDTTTF or ET), and bis(propylenedithio)tetrathiafulvalene (BPDT-TTF or PT) also found use in the preparation of salts in the course of this study. X-ray structural characterization of these salts revealed stacking between donor molecules containing significant S•••S interactions in the solid state. Various salts were subjected to either conductivity or molecular magnetism measurements in order to determine the level of itinerant electron density and magnetic contribution from paramagnetic charge compensating anions. In order to expand the library of TTF-containing hybrid materials prepared through metathesis, salts of other tetrathiafulvalenium radicals have also been prepared and characterized crystallographically and by select spectroscopic methods. In an effort to gain further information on formation of organic charge transfer complexes, TTF was combined with nitrofluorenone family of acceptors as well as the organocyanide acceptors HAT-(CN)6 (HAT-(CN)6 = 1,4,5,8,9,12-hexaazatriphenylenehexacarbonitrile) and TCNB (TCNB = 1,2,4,5-tetracyanobenzene). The complexes were characterized using X-ray crystallography, infrared spectroscopy, and molecular magnetism. All of these techniques showed that all compounds underwent little to no charge transfer. Commencing in 2003, the combined work of Dunbar and Omary revealed that systems combining inorganic donors with chelating, sulfur-based ligands and organic acceptors could have their spectroscopic response tuned to display low-energy charge transfer bands extending into the near-IR making them suitable candidates as photosensitizing dyes for semiconductors. In keeping with this idea, new layered charge transfer compounds combining the nitrofluorenone family of acceptors and the inorganic donor Pt(dbbpy)(tdt) (tdt = 3,4-toluenedithiolate) were prepared. The resulting complexes were characterized utilizing X-ray crystallography as well as both spectroscopic and electrochemical methods. Similar analyses were also conducted on various platinum/terpyridine salts and illustrated a level of spectroscopic tunability to that observed for the supramolcular systems composed of inorganic donors and organic acceptors.

Experiments and numerical predictions were conducted to study heat (mass) transfer characteristics in a two-pass trapezoidal channel simulating the cooling passage of a gas turbine blade. Three different rib configurations were tested for the air entering the smaller cross section of the trapezoidal channel as well as the larger cross section of the trapezoidal channel at four different Reynolds numbers of 9,400, 16,800, 31,800, and 57,200. (+) 60º ribs, (–) 60º ribs and 60º V-shaped ribs were attached on both the top and bottom walls in parallel sequence. A naphthalene sublimation technique was used, and the heat and mass transfer analogy was applied to convert the mass transfer coefficients to heat transfer coefficients. Numerical predictions of three-dimensional flow and heat transfer also were performed for the trapezoidal channel with and without 90º ribs tested by Lee et al. (2007). Reynolds stress turbulence model (RSM) in the FLUENT CFD code was used to calculate the heat transfer coefficients and flow fields at Re = 31,800. The results showed that the combined effects of the rib angle, rib orientation, and the sharp 180° turn significantly affected the heat (mass) transfer distributions. The secondary flows induced by the sharp 180° turn and the angled or V-shaped ribs played a very prominent role in heat (mass) transfer enhancements. The heat (mass) transfer enhancements and the pressure drops across the turn for 60° V-shaped ribs had the highest values, then came the case of (+) 60° ribs, and the heat (mass) transfer enhancements and the friction factor ratios for (–) 60º ribs was the lowest. However, comparing (–) 60º ribs with the 90º ribs, (–) 60º ribs produced higher heat (mass) transfer enhancements than the 90º ribs, as results of the secondary flow induced by the (–) 60º ribs. The overall average heat (mass) transfer for the larger inlet cases was always higher than that for the smaller inlet cases in the ribbed trapezoidal channel. Considering the thermal performance comparisons of the (+) 60° ribs, the (–) 60º ribs, and 60° V-shaped ribs for the smaller inlet cases, the highest thermal performance was produced by the (–) 60º ribs, and the 60° V-shaped ribs and the (+) 60° ribs had almost the same levels of the thermal performance since the 60° V-shaped ribs produced the highest heat (mass) transfer enhancement but also produced highest pressure drops. For the larger inlet cases, the (+) 60° ribs produced the highest values, then came the case of the 60° V-shaped ribs, and the thermal performance for the (–) 60º ribs was the lowest. The Reynolds stress model (RSM) showed well flow fields and heat transfer distributions but underpredicted average Nusselt number ratios.

Based on a cross-cultural comparison of requesting behavior between Koreans and Americans, the study tried to determine the extent of pragmatic transfer and the impact of individual subjective motives that may influence pragmatic language choice. Two different groups of subjects participated in this study: 30 Korean participants for Korean (KK) and also for interlanguage (KE) data who were studying English as a Second Language (ESL) in a U.S. university, and 30 American college students (AE). Data were collected by using a questionnaire with a Discourse Completion Task (DCT). Semi-structured interviews were also conducted with 13 Korean ESL learners who showed the highest and the least amount of pragmatic transfer. Findings showed evidence of pragmatic transfer in the request responses given by Korean ESL learners in the level of directness, perspectives of head acts, and the frequency of supportive moves and internal modifiers. The requesting behaviors of KE group were realized through more direct strategies than those of AE group. KE speakers had a tendency to use hearer-oriented requests more frequently than AE speakers, but slightly less than KK speakers, indicating that L1 transfer is operative. Pragmatic transfer occurred in three supportive moves such as Promise of Reward, Appreciation, and Apology and in three internal modifiers such as play-down, consultative device, and downtoner. The interviewees in this study were conscious of differing rules for requesting. Learners’ judgment of L2 pragmatic norms, the learners’ perception of their own language and their attitudes of the learned language have a determining influence on language use. Furthermore, findings showed that purpose of learning the L2, learners’ different types of motivation, and the length of residence intention contribute to the extent of pragmatic transfer. Finally, impossibility to acquire native-like proficiency, fear of disloyalty to their own culture, and preference of L1 styles as a marker of cultural identity seemed to be factors that influence learners’ pragmatic choices. Findings of this study offer implications that language educators need to recognize and plan for the different target goals language learners may have and that second/foreign language speakers also possess a desire to express their own identity.