4,190 research outputs found

    Modelling and design of high performance indium phosphide solar cells

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    A first principles pn junction device model has predicted new designs for high voltage, high efficiency InP solar cells. Measured InP material properties were applied and device parameters (thicknesses and doping) were adjusted to obtain optimal performance designs. Results indicate that p/n InP designs will provide higher voltages and higher energy conversion efficiencies than n/p structures. Improvements to n/p structures for increased efficiency are predicted. These new designs exploit the high absorption capabilities, relatively long diffusion lengths, and modest surface recombination velocities characteristic of InP. Predictions of performance indicate achievable open-circuit voltage values as high as 943 mV for InP and a practical maximum AM0 efficiency of 22.5 percent at 1 sun and 27 C. The details of the model, the optimal InP structure and the effect of individual parameter variations on device performance are presented

    Effects of Simulated Student Interaction on Student Perceptions of Teaching Presence

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    The purpose of this study was to explore the impact of the instructor posting in online discussions as a simulated student; particularly the impact simulated student interaction (SSI) had on the instructor/student relationship. Student perceptions were examined using a modified version of the Community of Inquiry (CoI) survey to determine what impact SSI had on teaching presence, cognitive presence, and social presence within the online classroom. The full 34 item CoI Survey was piloted in the summer of 2014 at a small comprehensive university located in northeast Texas. A factor analysis was conducted on the data and the top items from each factor in the instrument extracted. The resulting 17 item instrument demonstrated both validity and reliability. This modified CoI Survey was used in the fall of 2014 with three special education courses making up a control group and an intervention group in a pre-post experimental design. An ANOVA was performed to compare the results of the pre-course and post-course surveys by group. The ANOVA showed a statistically significant difference for all three factors for the intervention group between the pre- and post-course survey, while no significance between surveys was shown for the control group

    Workplace violence and the effect of the working environment and social support within a human service organisation : a thesis presented to Massey University in partial fulfillment of the requirements for the degree of Master of Science in Psychology

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    At the present time, there is an increasing awareness of the risk of workplace violence that certain occupational groups face within their professions. This study investigated violence within a human service organisation responsible for looking after profoundly intellectually handicapped individuals with little chance of being mainstreamed into normal society. Three hundred and forty three employees responded to a questionnaire about incidents of violence encountered at work, stressors within their job, and their perceptions of social support and the work environment. The hypotheses were (1) that symptoms of stress and traumatic stress increase in frequency and intensity following involvement in a violent incident, and will be cumulative and additive following repetitive exposure (2) that positive perceptions of the working environment decrease the symptoms of stress and traumatic stress ; and (3) that higher perceptions of the effectiveness of social support decrease the symptoms of stress and traumatic stress. The results showed that violence affected employees mentally, emotionally and physically. Perceptions of the work environment was found to have an effect on responses to violence but social support was not. Recommendations made included reducing violence by redesigning the physical environment, or the use of training to help with stress management. These results could help with the investigation of violence within the health care field

    Does the Performance on Principles of Economics Courses Affect the Overall Academic Success of Undergraduate Business Majors?

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    Using a sample of 1,339 graduates from an accredited business school and the maximum likelihood technique, this paper explores the relationship between overall academic success and performance on the Principles of Economics courses. The estimated model, which also includes some demographic variables, shows that the rank of professors teaching the course, age of students, and the number of credits earned do not influence business majors' overall academic success. However, the grades earned on the Principles of Economics courses, gender, ethnicity, the major in which the student is enrolled, the number of years the student takes to graduate, as well as whether or not the student is completing a minor significantly affect the overall academic success or the final GPA of business majors.

    CHARACTERISTICS OF MASTER'S PROGRAMS IN AGRIBUSINESS MANAGEMENT

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    This study describes and compares agribusiness master’s programs in North America. These programs include the master of business administration (MBA) and master in (or “of”) agribusiness (MAB) degrees. Accredited MBA programs with an agribusiness emphasis are required to have a clear required core of courses in finance, management, marketing management, and human behavior. Additional required courses in policy, agricultural marketing, production or managerial economics, and quantitative methods are also frequently required. MAB programs have more diversity regarding the four core subjects with a greater percentage of the courses taught within departments of agricultural economics. Evaluation of agribusiness master’s programs in agricultural economics departments is difficult without any formal evaluation criteria.Agribusiness, Teaching/Communication/Extension/Profession,

    A Method for Collaboratively Developing and Validating a Rubric

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    Assessing student learning outcomes relative to a valid and reliable standard that is academically-sound and employer-relevant presents a challenge to the scholarship of teaching and learning. In this paper, readers are guided through a method for collaboratively developing and validating a rubric that integrates baseline data collected from academics and professionals. The method addresses two additional goals: (1) to formulate and test a rubric as a teaching and learning protocol for a multi-section course taught by various instructors; and (2) to assure that students’ learning outcomes are consistently assessed against the rubric regardless of teacher or section. Steps in the process include formulating the rubric, collecting data, and sequentially analyzing the techniques used to validate the rubric and to insure precision in grading papers in multiple sections of a course

    Dynamic Potential-Ph Diagrams Application to Electrocatalysts for Water Oxidation

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    The construction and use of "dynamic potential-pH diagrams" (DPPDs), that are intended to extend the usefulness of thermodynamic Pourbaix diagrams to include kinetic considerations is described. As an example, DPPDs are presented for the comparison of electrocatalysts for water oxidation, i.e., the oxygen evolution reaction (OER), an important electrochemical reaction because of its key role in energy conversion devices and biological systems (water electrolyses, photoelectrochemical water splitting, plant photosynthesis). The criteria for obtaining kinetic data are discussed and a 3-D diagram, which shows the heterogeneous electron transfer kinetics of an electrochemical system as a function of pH and applied potential is presented. DPPDs are given for four catalysts: IrO(2), Co(3)O(4), Co(3)O(4) electrodeposited in a phosphate medium (Co-Pi) and Pt, allowing a direct comparison of the activity of different electrode materials over a broad range of experimental conditions (pH, potential, current density). In addition, the experimental setup and the factors affecting the accurate collection and presentation of data (e. g., reference electrode system, correction of ohmic drops, bubble formation) are discussed.Ministry of Education, University and Research PRIN 2008PF9TWZ, 2008N7CYL5Universita degli Studi di MilanoNational Science Foundation CHE-0808927Robert A. Welch Foundation F-0021Center for Electrochemistr

    Offices and Services: Women\u27s Pursuit of Sexual Equality within the Society of Friends, 1873 - 1907

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    The presence of Quaker women at the founding of a social movement for women\u27s rights in Britain in the late 1860s has received growing attention from historians in recent years. Yet the links between the religious faith of such Quaker women and their political radicalism has remained largely unexamined. A liberal theology which acknowledged the spiritual equality of women has been assumed to have prompted their involvement in a liberal politics, and more especially in women\u27s rights campaigning. This article argues that the relationship between religious views and political action was more complex in this case. It suggests that the growing participation of Quaker women in moral and social reform movements in this period, together with their increasing access to office in local government and voluntary organisations, served, in fact, to fuel a reevaluation of their position within the Society of Friends. It concludes that indeed the constitutional arrangements of this body became a ground of gender contest as a consequence of women\u27s enlarged role in the outside world

    An Arena for Success: Exploring Equine-Assisted Psychotherapy

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    Equine-Assisted Psychotherapy (EAP) is a relatively new experientially-based therapy that has been applied to individuals, couples, families, and groups. There is a small but growing literature base that speaks to EAP’s potential for working with very challenging clients. Adjudicated juveniles diagnosed with Oppositional Defi ant Disorder (ODD) are one such group. This paper contains a brief presentation of a case study that illustrates how EAP can be implemented, a description of the evolution of EAP, the components of EAP, and a discussion of the hypothesized mechanisms that account for its effectiveness
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