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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
281

Generation Y som investerare : en kvantitativ studie om hur generation Y:s karaktäristika påverkar deras investeringsbeteende

Toth, Gabriel, Vasovic, Milan January 2014 (has links)
Nyanländande Generation Y håller på att positionera sig på arbetsmarknaden och omfattas av individer födda inom intervallet 1980 – 1995. Det återfinns dessvärre ytterst lite forskning gällande generationens investeringsbeteende. Mestadels av tidigare forskning har hittills handlat om hur tidigare generationer, så som Baby Boomers och Generation X, tenderar att investera. Denna studie har därför försökt bidra till att fylla ut tomrummet i kunskapen beträffande Generation Y. Studien utreder investeringsbeteendet hos Generation Y genom att undersöka hur specifika karaktäristika påverkar deras sä̈tt att investera. Således är syftet med denna studie att kartlägga och analysera hur Generation Y:s särskilda karaktäristika påverkar deras investeringsbeteende. Tillvägagångssättet har varit att det först konstruerades en modell utifrån den redan tillgängliga forskningen, varpå uppsatsen därefter avsåg att testa validiteten och kvaliteten i våra antaganden och i den upprä̈ttade modellen. Uppsatsen utfördes med hjälp av en kvantitativ metod med positivistisk filosofi och deduktiv ansats. Undersökningsverktyget som till största grad användes för studien var en internetbaserad enkät där respondenterna fick ta del av en rad olika påståenden. Respondenterna som har deltagit i denna studie är till majoriteten bosatta i Sverige och omfattar respondenter som vid undersökningstillfället var 15 – 70 år. Denna studie indikerar slutligen att Generation Y har ett särskilt investeringsbeteende och att deras specifika sätt att investera på grundar sig i deras särskilda karaktäristika, vilket också påvisas med hjälp av ett antal statistiska modeller. Resultatet åskådliggör ytterligare att även demografiska faktorer som modersmål, kön och ålder påverkar investeringsbeteendet. Ett förslag till framtida forskning kan vara att komplettera uppsatsens kvantitativa metod med en kvalitativ metod. Detta tillvägagångssätt hade således kunnat bidra till en djupare förståelse för forskningen och ett bättre resultat och har därför varit av stort värde för uppsatsen. / The newly arriving Generation Y, that embraces the individuals born within 1980 – 1995, is on the way of positioning themselves on the labour-market. Unfortunately, there has not been done much research on the investment behavior of this generation. Mostly of previous research has been about how previous generations, the Baby Boomers and Generation X, tend to invest. This study therefore sought to help fill the gap in knowledge regarding the Generation Y. This study investigates the investment behavior of Generation Y by examining how specific characteristics affect their approach to investing. Thus, the purpose of this study was to identify and analyze how Generation Y’s specific characteristics affect their investment behavior. The approach has initially been that a model was constructed based on the already available research, whereupon the paper then aimed to test the validity and quality of our assumptions and of the established model. The essay was performed by a quantitative method with a positivistic philosophy and deductive logic. The research tool for this study was, to the biggest extent, an online survey in which a variety of claims were presented to the respondents. The respondents who participated in this study, with the majority residing in Sweden, were at the time of the study 15 – 70 years old. This study indicates that Generation Y has a particular investment behavior and that their specific way of investing is based on certain characteristics, which is also shown by the several statistical models that have been used. The result further illustrates that also demographic factors, such as native language, gender and age, has affection on the investment behavior of Generation Y. A proposal for future research might be to supplement the essay’s quantitative method with a qualitative one. This approach could possibly contribute to a deeper understanding of science and a better result, and would therefore be of great value to the essay.
282

Sustaining compressed air DSM project savings using an air leakage management system / A.J.M. van Tonder

Van Tonder, Adriaan Jacobus Marthinus January 2010 (has links)
Unreliable and unsustainable electricity supply has been experienced in South Africa since 2007. Eskom implemented Demand Side Management (DSM) as a short-term solution to alleviate this problem. Several compressed-air DSM projects were implemented to help reduce the strain on the electrical network. Compressed air is an integral part of production in deep-level mining, and is extensively utilised. Problems are encountered with the effective management and repairing of leaks, since the majority of mines have little to no procedures in place for leak management. Awareness of the condition of the compressed-air system and leaks needed to be created at management level in order to achieve the best results. The purpose of this study is to investigate the effect of proper leak management on compressed-air systems in the mining industry. Peak-clipping DSM projects implemented in the mining industry were used for evaluation of results. Contribution to the sustainability of compressed-air DSM projects savings through successful leak documentation was the prime focus of this study. This was achieved through the development of a Compressed Air Leakage Documentation System (CALDS). This entailed the electronic field-data capture and record keeping of field data, using rugged PDA devices suitable for the extreme environmental conditions encountered in deep-level mining. Report generation on the status of detected leaks created awareness of compressedair- system performance and leak-repair tracking at management level. Audible detection was sufficient for this study, since the focus was on the larger more-severe leaks. Leaks were expressed in monetary terms to indicate the severity. It was found that successful management of leaks could contribute to an increase of as much as 85% in project savings. The results also showed that creating awareness through documentation of leaks, and the effect this has on the system, resulted in regular repairing of these leaks. Sustainability of projects was maintained during an evaluation period of ten months, with projects achieving on average 125% of target savings. The study showed that effective reporting on compressed-air leaks resulted in increased system efficiency and sustainable DSM project savings. It was also seen that leak detection by outsourced companies did not necessarily result in financial savings. When the mine took responsibility for its own leak detection and repairs, significant savings were realised. / Thesis (M.Ing. (Electrical and Electronic Engineering))--North-West University, Potchefstroom Campus, 2011.
283

Energy efficiency opportunities in mine compressed air systems / F.W. Schroeder

Schroeder, Frederick William January 2009 (has links)
Demand Side Management (DSM) is one of the most viable and sustainable short term methods to address the shortfall in electricity generation in South Africa. This is because DSM projects can be implemented relatively quickly and inexpensively when compared with alternative generation options. This specifically applies to the mining industry. South African mines presently consume 15% of Eskom-generated electricity. Mine compressed air systems are some of the biggest users, consuming approximately 21% of mine electricity consumption. Electricity savings on compressed air systems are therefore important. With this study, various Energy Efficiency methods on compressed air systems were investigated. These methods include variable speed drives on compressor motors, temperature control of compressor discharge, minimising pressure drops in the air distribution systems, eliminating compressed air leaks, and optimising compressor selection and control. The most efficient strategies were identified, taking into account factors such as financial viability, sustainability, and ease of implementation. The best strategies were found to be the optimised control and selection of compressors, minimising compressed air leaks, and the optimal control of system pressure. These strategies were implemented and tested on large compressed air systems in gold and platinum mines. Savings of between 10% and 35% on the maximum demand of the systems were achieved. In present monetary terms this translates to as much as R108 million savings for the mines per year at the end of 2009 tariffs. If total mine compressed air electricity consumption can reduce by 30%, it will result in nearly a 1% reduction in total Eskom demand. This shows that mine compressed air savings can make a significant contribution to the drive for Energy Efficiency in South Africa. / Thesis (M.Ing. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2010.
284

Sustaining compressed air DSM project savings using an air leakage management system / A.J.M. van Tonder

Van Tonder, Adriaan Jacobus Marthinus January 2010 (has links)
Unreliable and unsustainable electricity supply has been experienced in South Africa since 2007. Eskom implemented Demand Side Management (DSM) as a short-term solution to alleviate this problem. Several compressed-air DSM projects were implemented to help reduce the strain on the electrical network. Compressed air is an integral part of production in deep-level mining, and is extensively utilised. Problems are encountered with the effective management and repairing of leaks, since the majority of mines have little to no procedures in place for leak management. Awareness of the condition of the compressed-air system and leaks needed to be created at management level in order to achieve the best results. The purpose of this study is to investigate the effect of proper leak management on compressed-air systems in the mining industry. Peak-clipping DSM projects implemented in the mining industry were used for evaluation of results. Contribution to the sustainability of compressed-air DSM projects savings through successful leak documentation was the prime focus of this study. This was achieved through the development of a Compressed Air Leakage Documentation System (CALDS). This entailed the electronic field-data capture and record keeping of field data, using rugged PDA devices suitable for the extreme environmental conditions encountered in deep-level mining. Report generation on the status of detected leaks created awareness of compressedair- system performance and leak-repair tracking at management level. Audible detection was sufficient for this study, since the focus was on the larger more-severe leaks. Leaks were expressed in monetary terms to indicate the severity. It was found that successful management of leaks could contribute to an increase of as much as 85% in project savings. The results also showed that creating awareness through documentation of leaks, and the effect this has on the system, resulted in regular repairing of these leaks. Sustainability of projects was maintained during an evaluation period of ten months, with projects achieving on average 125% of target savings. The study showed that effective reporting on compressed-air leaks resulted in increased system efficiency and sustainable DSM project savings. It was also seen that leak detection by outsourced companies did not necessarily result in financial savings. When the mine took responsibility for its own leak detection and repairs, significant savings were realised. / Thesis (M.Ing. (Electrical and Electronic Engineering))--North-West University, Potchefstroom Campus, 2011.
285

Energy efficiency opportunities in mine compressed air systems / F.W. Schroeder

Schroeder, Frederick William January 2009 (has links)
Demand Side Management (DSM) is one of the most viable and sustainable short term methods to address the shortfall in electricity generation in South Africa. This is because DSM projects can be implemented relatively quickly and inexpensively when compared with alternative generation options. This specifically applies to the mining industry. South African mines presently consume 15% of Eskom-generated electricity. Mine compressed air systems are some of the biggest users, consuming approximately 21% of mine electricity consumption. Electricity savings on compressed air systems are therefore important. With this study, various Energy Efficiency methods on compressed air systems were investigated. These methods include variable speed drives on compressor motors, temperature control of compressor discharge, minimising pressure drops in the air distribution systems, eliminating compressed air leaks, and optimising compressor selection and control. The most efficient strategies were identified, taking into account factors such as financial viability, sustainability, and ease of implementation. The best strategies were found to be the optimised control and selection of compressors, minimising compressed air leaks, and the optimal control of system pressure. These strategies were implemented and tested on large compressed air systems in gold and platinum mines. Savings of between 10% and 35% on the maximum demand of the systems were achieved. In present monetary terms this translates to as much as R108 million savings for the mines per year at the end of 2009 tariffs. If total mine compressed air electricity consumption can reduce by 30%, it will result in nearly a 1% reduction in total Eskom demand. This shows that mine compressed air savings can make a significant contribution to the drive for Energy Efficiency in South Africa. / Thesis (M.Ing. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2010.
286

Numerical investigations of airflow and heat transfer in traditional Balinese buildings

Wijaya Kusuma, I. Gusti Bagus January 1999 (has links)
Traditional Balinese architecture is commonly related to culture and traditional reasoning. When subjected to several modem problems such as energy demand, pollution, and impact of urbanisation and tourism, traditional architecture becomes less attractive since the definitions behind traditional reasoning are not clear and can be interpreted in different ways. To understand this feature, the study of traditional Balinese architecture starts by using several key parameters such as wind engineering and heat transfer, as presented and used in several countries. The flow patterns around a cubic building have been studied by many researchers. The velocity profile at the model position and the local surface roughness are specific to each building model and cannot be estimated from general tests of a standard building shape, therefore specific velocity profiles and conditions are used in this particular study. The air flow around a cluster of traditional Balinese buildings is extremely complicated and difficult to determine by modelling an isolated building (via symmetric conditions) since the buildings are linked to each other. Full scale models of traditional buildings have been investigated by using CFD to predict the above aspects. Simulations using this method can be done more quickly and less expensively than with wind tunnel experiments, and are capable of delivering more detailed and comprehensive information about the flow structure. Two-dimensional models of traditional Balinese building arrangements are simulated by using a commercial code Fidap based on the finite element method to assess the effects of type of roof, fence and surface roughness. Three-dimensional models are simulated by using a commercial code CFX based on the finite volume method to verify some traditional definitions. A standard к-ε model is adopted because it needs less computational power and has achieved notable successes in calculating a wide variety of thin shear layer and recirculating flows without the need of adjustment of the model constants, but with the imposition of boundary conditions to reduce the over-prediction near windward edges. Adopting lower values of к and ε combined with multi-blocks is shown to reduce this over-estimation. For a cubic building, the results can be compared with several other turbulence models. It appears that traditional Balinese architecture has a strong and significant correlation with several engineering fields, therefore traditional communities can develop by considering the Tri Hita Karana concept in order to improve thermal comfort and reduce cooling loads, with corresponding energy savings.
287

Rule-based integrated building management systems

Clark, Gary George January 1993 (has links)
The introduction of building management systems in large buildings have improved the control of building services and provided energy savings. However, current building management systems are limited by the physical level of integration of the building's services and the lack of intelligence provided in the control algorithms. This thesis proposes a new approach to the design and operation of building management systems using rule-based artificial intelligence techniques. The main aim of is to manage the services in the building in a more co-ordinated and intelligent manner than is possible by conventional techniques. This approach also aims to reduce the operational cost of the building by automatically tuning the energy consumption in accordance with occupancy profile of the building. A rule-based design methodology is proposed for building management systems. The design adopts the integrated structure made possible by the introduction of a common communications network for building services. The 'intelligence' is coded in the form of rules in such a way that it is both independent of any specific building description and easy to facilitate subsequent modification and addition. This is achieved using an object-oriented approach and classifying the range of data available into defined classes. The rules are divided into two knowledge-bases which are concerned with the building's control and its facilities management respectively. A wide range of rule-based features are proposed to operate on this data structure and are classified in terms of the data classes on which they operate. The concepts presented in this thesis were evaluated using software simulations, mathematical analysis and some hardware implementation. The conclusions of this work are that a rule-based building management system could provide significant enhancements over existing systems in terms of energy savings and improvements for both the building's management staff and its occupants.
288

A pragmatic value-driven approach to design with applications to energy-conscious buildings

Lee, Benjamin David 12 January 2015 (has links)
Within the design community, a growing number of researchers have shown interest in extending the value context to include design, such that designers focus on maximizing the 'value' of the product or service, rather than simply satisfying a set of requirements. Thus, by applying a value-driven approach to design, the design community hopes to show that the magnitude of cost and schedule overruns may be reduced, or even eliminated. However, a common criticism of value-driven approaches is that they are difficult to implement, and not sufficiently pragmatic to be used for large scale engineering problems. Further, some argue that less rigorous methods appear to provide reasonable results in practice, and so rigor is not necessary. To reconcile these disparate viewpoints, it must be shown that value-driven approaches contribute to the design process, and can be implemented in practice at a reasonable cost. In response, I propose that the cause for the lack of practicality in value-driven approaches is attributable to the lack of well established and verified methods and tools. This dissertation presents research that attempts to address this deficiency by first developing a better understanding of effectiveness for methods that seek to enable value-driven design. This investigation leads to a concise set of desired characteristics for methods for guiding the development of value-models which then motivate the creation of a Systematic Method for Developing Value Models (SMDVM). To evaluate the SMDVM, it is applied to the design and retrofit of buildings for energy efficiency. A simulation workbench is developed as a tool to automate the development and analysis of value models for building design and retrofit contexts. The workbench enables architects, engineers, and other practitioners to easily incorporate uncertainty into analyses of building energy consumption, as part of a value-driven approach to design and retrofit.
289

The role of nonbank intermediation in a financially repressed economy (theory and evidence based on the Korean economy, 1972--1994)

Choi, Joong-Kyung 08 1900 (has links)
In existing economic literature on finance and economy, it is argued and generally accepted that financial intermediation contributes to economic growth though the contending argument is that financial development is simply a result of economic growth. However, studies on the contribution of financial intermediation of nonbanks (as opposed to banks) to economic growth are relatively scant and too general to clarify the mechanism through which nonbank financial intermediation might help economy to expand and develop. The focus of this study is on whether nonbank financial intermediation contributed to economic growth in the case of Korea where the share of nonbank financial intermediation increased from around 20% in 1970 to more than 60% in the early 1990's. This study is particularly interesting in light of the fact that rapid economic growth in Korea was accompanied by a concomitant increase in the share of nonbank financial intermediation. As a precursor to the empirical analysis, this study shows theoretically that financial intermediation of nonbanks subject to lesser liquidity control is complementary to, rather substitutional for, that of banks. Further, it is shown by optimizing a two-period dynamic model that under certain conditions nonbank intermediation increases an economy's savings mobilization and contributes to the economic growth. For empirical analysis, we used the annual data from 1972 to 1994 which can be considered as a financially repressed period. The empirical results are all consistent with the theoretically expected: nonbanks are complementary to banks in financial intermediation, increased the savings mobilization, and in the end contributed to the economic growth of the Korean economy during the sample period. Further, the estimated allocative efficiencies of nonbanks are almost in phase with business cycles, which may well be interpreted as consistent with the proposition that nonbanks financial intermediation made a significant contribution to Korea's economic growth.
290

An investigative analysis into the saving behaviour of poor households in developing countries: with specific reference to South Africa.

Nga, Marie-Therese January 2007 (has links)
<p>In South Africa, as in many developing countries, most households are poor and do not save, as a result of which they do not acquire any positive net worth and which also constrains access to formal means of finance. South Africa is a consuming nation, with increasing ratios of household consumption resulting in dissaving and often unsustainable levels of household debt, which is also stimulated by the current lower level of interest rates. This situation is worse amongst poorhouseholds who also often experience financial shocks, for instance because of the death of family membersas a result of HIV/AIDS. This report provided an overview of household saving in South Africa for the period 1983 to 2003. It identified the main factors responsible for the lack of a commitment to saving which are particularly relevant in the case of poor households.</p>

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