Experimental investigation and numerical simulation of a copper micro-channel heat exchanger with HFE-7200 working fluid

Ever increasing cost and consumption of global energy resources has inspired the development of energy harvesting techniques which increase system efficiency, sustainability, and environmental impact by using waste energy otherwise lost to the surroundings. As part of a larger effort to produce a multi-energy source prototype, this study focused on the fabrication and testing of a waste heat recovery micro-channel heat exchanger. Reducing cost and facility requirements were a priority for potential industry and commercial adoption of such energy harvesting devices. During development of the micro-channel heat exchanger, a new fabrication process using mature technologies was created that reduced cost, time, and required equipment. Testing involved filling the micro-channel heat exchanger with 3MTM NovecTM HFE-7200 working fluid. The working fluid was chosen for appropriate physical and environmental properties for the prototypes intended application. Using a dry heat exchanger as the baseline, the addition of the working fluid proved advantageous by increasing energy output by 8% while decreasing overall device temperatures. Upon successful experimental testing of the physical device, internal operation was determined based on implementation of the lattice Boltzmann method, a physics-based statistical method that actively tracked the phase change occurring in a simulated micro-channel. The simulation demonstrated three primary areas of phase change occurring, surfaces adjacent to where the heat source and heat sink were located and the bulk vapor-liquid interface, which agreed with initial device design intentions. Condensation film thickness grew to 5µm over the time interval, while the bulk interface tracked from initial 12µm from the lid to 20µm from the lid. Surface tension effects dominating vapor pressure kept the liquid near the heat source; however, the temperature and pressure VLE data suggested vapor interface growth from the heated surface to 5µm above the heated copper plate. Reinforcing the simulation results, including location and movement of phase interfaces, was accomplished through a thorough ten dimensionless number analyses. These specialized ratios indicated dominant fluid and heat transfer behavior including phase change conditions. Thus, fabrication and empirical results for the heat energy harvesting prototype were successful and computational modeling provided understanding of applicable internal system behavior

The context and enactment of faith-based social entrepreneurship : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy at Massey University, Auckland, New Zealand

Faith-based organisations have been at the forefront of efforts to meet human need and effect positive social change for centuries, and they continue to make significant contributions to social welfare. However, a paucity of empirical research into the nature of faith-based social entrepreneurship limits knowledge and theory development and hinders the effectiveness of faith-based initiatives. In response, this thesis explores how a religious worldview intersects with values, gender and institutional logics to influence social entrepreneurial activity. The thesis thereby aims to develop new theoretical insights into the contextual embeddedness of the process of social entrepreneurship. Qualitative, interpretive research based on a social constructionist paradigm was conducted to explore how a religious faith context influences the enactment of social entrepreneurship. Comparative multiple case studies of eight social entrepreneurial organisations located in the Philippines, Thailand and Vietnam were undertaken during the period 2016-18. Faith-based, faith-inspired and secular organisations participated in the research. Multilevel thematic analysis of data employed theoretical lenses of universal human values, gender and institutional logics. The research showed that faith-based social entrepreneurship is a distinct, contextually embedded expression of social entrepreneurship. Findings suggest that a religious worldview, values and gender are discrete contexts that influence the what, where, how, who, when and why omnibus contexts in which social entrepreneurship is enacted. In a religious worldview context, social entrepreneurial organisations respond not only to well-documented social welfare and commercial logics but also to a religious metalogic. Consequently, faith-based social entrepreneurial organisations illuminate how organisations experience institutional complexity and manage paradoxical interlogic tensions. The key insight and contribution of the thesis is that contexts of a Christian religious worldview and gender underscore the values-based nature of social entrepreneurship. Further, these contexts reveal the influence of faith, altruistic love and the logic of gratuitous giving on how social entrepreneurship is experienced and enacted

The Context and Enactment of Faith-based Social Entrepreneurship

Faith-based organisations have been at the forefront of efforts to meet human need and effect positive social change for centuries, and they continue to make significant contributions to social welfare. However, a paucity of empirical research into the nature of faith-based social entrepreneurship limits knowledge and theory development and hinders the effectiveness of faith-based initiatives. In response, this thesis explores how a religious worldview intersects with values, gender and institutional logics to influence social entrepreneurial activity. The thesis thereby aims to develop new theoretical insights into the contextual embeddedness of the process of social entrepreneurship. Qualitative, interpretive research based on a social constructionist paradigm was conducted to explore how a religious faith context influences the enactment of social entrepreneurship. Comparative multiple case studies of eight social entrepreneurial organisations located in the Philippines, Thailand and Vietnam were undertaken during the period 2016-18. Faith-based, faith-inspired and secular organisations participated in the research. Multilevel thematic analysis of data employed theoretical lenses of universal human values, gender and institutional logics. The research showed that faith-based social entrepreneurship is a distinct, contextually embedded expression of social entrepreneurship. Findings suggest that a religious worldview, values and gender are discrete contexts that influence the what, where, how, who, when and why omnibus contexts in which social entrepreneurship is enacted. In a religious worldview context, social entrepreneurial organisations respond not only to well-documented social welfare and commercial logics but also to a religious metalogic. Consequently, faith-based social entrepreneurial organisations illuminate how organisations experience institutional complexity and manage paradoxical interlogic tensions. The key insight and contribution of the thesis is that contexts of a Christian religious worldview and gender underscore the values-based nature of social entrepreneurship. Further, these contexts reveal the influence of faith, altruistic love and the logic of gratuitous giving on how social entrepreneurship is experienced and enacted

What’s Love Got to Do with It? Religion and the Multiple Logic Tensions of Social Enterprise

This paper develops a model that advances our understanding of how social enterprises respond to the complexity of a constellation of multiple, often competing goals, referred to here as institutional logics. Introducing a religious logic to the recognised social welfare and commercial logics of social enterprise, this model builds on a religious worldview foundation and incorporates religion-inspired altruistic love and non-transactional giving as its scaffolding. A comparative case study of faith-based, faith-inspired and secular organisations located in Southeast Asia demonstrates the origin and applicability of the model. Findings highlight that religion serves as an overarching logic, or “metalogic”, and frame of reference. Faith-based social enterprises use this religious logic to redefine perceived paradoxical tensions between the social welfare and commercial objectives they embody. Study results advance knowledge on organisational responses to multiple logic prescriptions, underscores the influence of religion, altruistic love and giving on organisational behaviour and contributes to the scarce literature on faith-based social enterprises

Job Satisfaction of Administrators in a Public Suburban School District

The two research questions of the study were: (1) Is the job satisfaction of school district administrators related to the personal factors of group membership and sex? (2) What are the sources of overall job satisfaction? Do they confirm findings from previous studies in which autonomy, responsibility, the work itself, growth, recognition, feedback, achievement, and interpersonal relationships were found to be major contributors to job satisfaction? Utilizing the Job Diagnostic Survey (JDS) developed by Hackman and Oldham and free response questions, ratings of job satisfaction were obtained to determine if sex and group membership (elementary principal, secondary principal and vice principal, or central office administrator) made a difference in the level of job satisfaction. The findings from the two research questions were: (1) Group membership and sex do not significantly relate to job satisfaction. (2) Approximately 22% of job satisfaction for administrators was attributed to autonomy and feedback from the work itself. Data gathered from the free response questions did reveal some differences in the sources of job satisfaction and dissatisfaction according to group membership. The main sources of satisfaction--regardless of group membership--involved the work itself, achievement, and interpersonal relationships. Recognition was also seen as a source of satisfaction at the central office and secondary level. Student performance and interaction was seen as a primary source of satisfaction at the elementary and secondary level. Autonomy was a main source of satisfaction at both the elementary and central office level. The main sources of dissatisfaction--regardless of group membership--involved amount of work, lack of feedback, constraints, and administrative policies. While interpersonal relationships were seen as sources of satisfaction by 25% of those responding administrators in central office positions, 60% of the responding administrators identified them as sources of dissatisfaction. The findings of this study imply that boards of education and upper-echelon administrators should be aware of the motivational potential in the two factors of autonomy and feedback and in the identified areas of job satisfaction and dissatisfaction. Opportunities which allow for greater administrator autonomy and feedback should be expanded in order to increase job satisfaction

Faith-based social entrepreneurship: Towards an integrative framework

The study of social entrepreneurship increasingly takes into consideration the multi-faceted context that generates and shapes it. Inspired and guided by the specific context of religion, faith-based organisations throughout history have been at the forefront of non-profit activities to address social challenges. This paper is motivated by the empirical observation that the activities and practices of faith-based organisations are changing in response to the contemporary context of social and environmental problems. It interrogates the prevailing discourse in the field in order to contribute toward an understanding of the complex phenomenon of faith-based social entrepreneurship. Identifying two distinct standpoints - “marketplace mission” and “integral mission” - the paper moves toward a conceptual framework that positions these two aspects with respect to social entrepreneurship. Faith-based social entrepreneurship is argued to be a synthesis that combines elements of commercial entrepreneurship, social action, and religious mission.falsePublishedAuckland, New Zealan

Faith-Based Social Entrepreneurship: Towards an Integrative Framework

falsePublishe

A cost-minimisation study of alternative discharge policies after hip fracture repair

It is widely assumed that health care costs can be reduced considerably by providing care in appropriate health care institutions without unnecessary technological overhead. This assumption has been tested in a prospective study. Conventional discharge after hip fracture surgery was compared with an early discharge policy in which patients were discharged to a nursing home with specialised facilities for rehabilitation. We compared costs for both strategies from a societal perspective, using comprehensive and detailed data on type of residence and all kinds of medical consumption during a 4-month follow-up period. As expected, early discharge reduced the hospital stay (with 13 days, p=0.001). More patients were discharged to a nursing home (76% versus 53%). Total medical costs during follow-up were reduced from an average of €15 338 to €14 281, representing relatively small and not significant savings (p=0.3). There are two explanations for this unexpected result. First, costs incurred by hip fracture patients were relatively less while in hospital. Hence, nursing home costs almost equalled hospital costs per admission day. Second, compared with the conventionally discharged group early discharged patients were subjected to more medical procedures during the first post-operative days. We conclude that: (1) early discharge shifted rather than reduced costs; (2) the details of costing have a major influence on the cost-effectiveness of alternative discharge policies. Copyright © 2002 John Wiley & Sons, Ltd.