The goal of Master's Thesis is an identification of life cycle costs of vacuum cleaners. Next point is an analysis of these life cycle cost by using value analysis. The theoretical part is focused on definitions of Life Cycle Costing (LCC) and Value Analysis (VA). The practical part, which is fundamental, contains identification of life cycle cost of selected vacuum cleaners, life cycle costing of selected vacuum cleaners and their value analysis. Result of this Master's Thesis is an interpretation of the results and the suggestion of steps for consumers and producers of vacuum cleaners.

Thesis (M.Ing. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2008.

This thesis investigates a special type of energy system, namely energy use in supermarkets through modelling, simulations and field studies. A user-friendly computer program, CyberMart, which calculates the total energy performance of a supermarket, is presented. The modelling method described in this thesis has four phases: the first phase is the de-velopment of a conceptual model that includes its objectives, the envi-ronment and the components of the system, and their interconnections. The second phase is a quantitative model in which the ideas from the conceptual model are transformed into mathematical and physical rela-tionships. The third phase is an evaluation of the model with a sensitivity analysis of its predictions and comparisons between the computer model and results from field measurements. The fourth phase is the model ap-plication in which the computer model answers questions identified in the beginning of the modelling process as well as other questions arising throughout the work. Field measurements in seven different supermarkets in Sweden were car-ried out to: (i) investigate the most important parameters that influence energy performance in supermarkets, (ii) analyse the operation of new system designs with indirect system implementation in Sweden during recent years, and (iii) validate the computer model. A thorough sensitivity analysis shows a total sensitivity of 5.6 %, which is a satisfactory result given a 10% change in the majority of input parame-ters and assumptions, with the exception of outdoor temperatures and solar radiation that were calculated as extreme values in METEO-NORM. Comparisons between measurements and simulations in five supermarkets also show a good agreement. Measurements and simula-tion results for a whole year were not possible due to lack of data. CyberMart opens up perspectives for designers and engineers in the field by providing innovative opportunities for assessment and testing of new energy efficient measures but also for evaluation of different already-installed system designs and components. The implementation of new energy-saving technologies in supermarkets requires an extensive inte-grated analysis of the energy performances of the refrigeration system, HVAC system, lighting, equipment, and the total energy usage. This analysis should be done over a long period, to evaluate and compare the real energy performance with the theoretical values calculated by Cyber-Mart. / QC 20100330

This report analyzes disposable packaging and returnable packaging with the methods life cycle analysis and life cycle costs analysis. These two different packaging are analyzed through the company Clas Ohlson’s packaging-flow. To get a picture of how the flow works, a visit at the company and email contact have been done with Clas Ohlson to get relevant information Today Clas Ohlson has a big flow of articles to the stores without larger variations in the demand, with the exception of autumn, which is when customers start shopping for Christmas. Clas Ohlson’s articles are placed on a pallet and are wrapped into plastic-film for protection and to make sure that nothing will be stolen. In this report Plastic-film is compared to the company Nycopac AB’s product Nyco Sleeve. In Sweden Posten takes care of Clas Ohlson’s transports and is the company’s third party-logistics provider. Nyco Sleeve is a type of pallet box, which is placed on a pallet with the possibility to place three units upon each other. The pallet box is possible to fold, which makes it doable to place pallet boxes upon each other in reverse transportation. Our Life cycle costs analysis shows that Nyco Sleeve is profitable compared to continue using plastic-film as secondary packaging. Nyco Sleeve demands a larger investment, almost seven times larger than the price for plastic-film but the expenses will be recovered relatively fast because of decreasing transportation costs. Posten’s pricing depends on each pallet place that is used which means that Nyco Sleeve’s higher weight does not affect the price. The total costs decreases because Nyco Sleeve increases the fill ratio on each pallet place, which results that less pallet places need to be used in the transport. If Nyco Sleeve is used the total pallet places decrease from about 116 000 to about 93 000 pallets considering 2012s flow. Due to decreasing costs each year, the pay-off-method shows that the investment reaches break even in about 0.7 years The life cycle analysis that examines the environmental impact of the packaging shows the same trend as the life cycle cost analysis, it is the transport that has the decisive influence on the environment. Important to note is that the transportations from Clas Ohlson’s warehouse to stores and the reverse transports stand for the largest carbon dioxide emissions and not the transportations from production or to waste disposal. The production phase’s emission is also important especially for Nyco Sleeve, which causes large amounts of emission compared to the plastic film. Decreasing transportations and that it is possible to reuse Nyco Sleeve even out the differences between the two packaging types when it comes to emission in production. The life cycle analysis’ scenario analysis shows that Nyco Sleeve environmental impact reaches break even after about two years compared to break even for the economic costs in 0.7 years. If only one loop is investigated the calculations show that Nyco Sleeve has larger environmental impact then plastic film but over time and when several loops are considered Nyco Sleeves carbon dioxide emission is economized. / Rapporten analyserar engångs- och returemballage genom de två analysmetoderna, livscykelkostnads- och livscykelanalys. Emballagen analyseras utifrån företaget Clas Ohlsons emballageflöde där studiebesök gjorts för att se hur flödet fungerar. Mailkontakt har också förekommit för annan viktig information kring företagets flöde av artiklar och emballage. Clas Ohlson har idag ett stort och jämnt flöde av produkter till deras butiker med säsongstoppar på hösten inför julhandeln. Deras produkter paketeras idag på lastpallar som sedan sveps in i plastfilm för att skydda och säkerställa att ingen stöld har skett. Det är detta engångsemballage, plastfilm, som jämförs emot returemballaget, Nyco Sleeve. Clas Ohlsons transporter sker idag med en tredjepartslogistiker där Posten är deras distributör inom Sveriges gränser, som är det system som undersöks. Nyco Sleeve är en form av pallbox som ställs på en lastpall och det går lasta tre stycken i höjd, ovan på varandra. Pallboxen går att fälla ihop vid returer och lastas även då ovan på varandra. Livscykelkostnadsanalysen visar att Nyco Sleeve är en ekonomisk lönsam investering i relation till att behålla plastfilmen som sekundärförpackning. Kostnaden att investera i Nyco Sleeve är ca sju gånger högre i jämförelse med inköpskostnaden för plastfilmen, men investeringen blir lönsam relativt snabbt eftersom Nyco Sleeve sänker transportkostnaderna. Posten tar idag betalt per pallplats och därmed gör inte tyngden på en Nyco Sleeve någon påverkan på den ekonomiska kostnaden. Kostnaden minskar genom användning av Nyco Sleeve eftersom fyllnadsgraden ökar och därmed minskar antalet levererade pallplatser. Skulle Nyco Sleeve användas minskas antalet från 116 100 stycken till ca 93 000 pallplatser utifrån Clas Ohlsons flöde under 2012. Genom den stora transportbesparingen per år visar pay-off-metoden att investeringen når break-even efter omkring 0,7 år. Livscykelanalysen som undersöker emballagens koldioxidutsläpp visar på samma tendens som livscykelkostnadsanalysen, att det är transporten som är den stora miljöboven. Viktigt att poängtera är att det är transporterna från Clas Ohlsons centrallager ut till butikerna och returtransporterna för samma sträcka som ger störst miljöpåverkan och inte transporterna från emballagens produktionsanläggningar till centrallagret eller till avfallshanteringen. Produktionen är även den en stor aktivitet som ger stor miljöpåverkan där Nyco Sleeve bidrar till betydligt större utsläpp än plastfilmen. Den stora skillnaden i miljöpåverkan från produktionen kompenseras genom de minskade transporterna och att Nyco Sleeve återanvänds. Livscykelanalysens scenarioanalys visar att Nyco Sleeves miljöpåverkan når break even efter ca två år. Undersöks bara en loop visar beräkningarna att Nyco Sleeve har större miljöpåverkan än om plastfilm används men detta inbesparas genom de minskade transporterna.

In a world with limited resources and serious environmental, social and economical impacts, a more sustainable life style is everyday more important. Therefore, the general objective of this work is to develop a methodological procedure for eco-efficiency and sustainability assessment of industrial processes with multi-scale technology at design level. The methodology developed follows the ISO 14040 series for environmental LCA standard. To integrate the three pillars of sustainability the analytical hierarchical process was used. The results are represented in a triple bottom line framework. The methodology was applied to the case study "production of perfume-containing microcapsules" and different scenarios were assessed and compared. Several sustainability indicators were chosen to analyze the impacts. The results showed that this methodology can be used as a decision making tool for sustainability reporting. It can be applied to any process choosing in each case the corresponding set of inventory data and sustainability impact indicators. / En un mundo con recursos limitados y graves impactos ambientales, sociales y económicos, un estilo de vida más sostenible es cada día más importante. Debido a esto, el objetivo general de este trabajo es desarrollar un procedimiento metodológico para evaluar eco-eficiencia y sostenibilidad de procesos industriales con tecnología multi-escala a nivel de diseño. La metodología desarrollada sigue la serie ISO 14040 para el medio ambiente. Se utilizó el proceso analítico jerárquico para integrar los tres pilares de sostenibilidad. Los resultados se presentan en un balance triple. La metodología se aplicó al caso de estudio "producción de micro-cápsulas que contienen perfume" y se analizaron y compararon diferentes escenarios. Se seleccionaron diversos indicadores de sostenibilidad para analizar los impactos. Los resultados demostraron que esta metodología puede ser utilizada como herramienta de toma de decisiones y que puede aplicarse a cualquier proceso seleccionando, en cada caso, los datos del inventario y los indicadores.

I denna rapport har det utförts två fallstudier från två olika vindkraftsanläggningar och med hjälp av en utarbetad modell har livscykelkostnaderna jämförts för de två fallstudierna.Resultatet visade att livscykelkostnaden per producerad kWh sjunker allteftersom den installerade effekten blir högre.Kostnadsmodellen som utarbetats och tillämpats för resultaten har visat sig ha hög verifierbarhet då resultaten har varit jämförbara med litterära studier. / In this report, conducted two case studies from two wind farms and using an elaborate model, life cycle costs compared to the two case studies.The results showed that the lifecycle cost per kWh decreases as the installed power increases.Cost model as developed and applied to generate the reported results have been generated in the results that are comparable to literary studies.

Selecting a suitable power source, during the design process, for a stand-alone soya business unit is challenging and complex. Especially with the aim of optimizing electrical and thermal energy, as well as minimizing the life cycle cost. During the design and development of a soya business unit it was realized that a design tool is needed to assist with the decision making process when selecting a power source. Waste heat can be recovered from either or both the exhaust gas and cooling system of the power source and can be utilized in the soya process. Research of available literature revealed no design tool to assist with the decision making process of the stand-alone business unit and consequently lead to this study. This dissertation presents different possible power sources that could be utilized in supplying energy to the business unit, as well as design tools available. Advantages and disadvantages of the different power sources are discussed. The shortfalls of a number of the available design tools are also discussed. A diesel generator set was selected as the preferred power source for the business unit. Criteria for this selection included the price per kWhe generated, the ease of maintenance, the availability of the diesel generators in rural areas and the availability of diesel as a fuel. The diesel engine was characterized through experimental work for a more in depth understanding of the energy profile of the engine at part load conditions. These results were used as guidelines in the development of the design tool. The design tool was developed with the aim of being user friendly and versatile. The time intervals of the required load of the business unit are flexible. Different types of power sources and fuels can be used within the design tool. User defined heat exchangers are utilized to calculate the possible heat recovery from the power source. The design tool matches the available energy of different power sources at part load conditions with the required load profile of the soya business unit. It then eliminates power sources that would not be able to deliver the minimum required energy. The running cost is calculated for each of the remaining power sources and the power source with the minimum annualized cost, which includes capital cost, maintenance cost and fuel cost, is suggested. The design tool was verified against a base load condition of the soya business unit and the suggested power source showed a saving of 31,4% in electrical energy, an increased overall efficiency of 24,9% and a saving in annualized cost of 27,3%. The design tool can be used to optimize specific components and design options within a combined heat and power system. Sensitivity analysis can be performed with the design tool to determine various influences on the designed system. / Thesis (M.Ing. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2008.

Linear covalently closed (LCC) DNA minivectors serve to be superior to conventional circular covalently closed (CCC) plasmid DNA (pDNA) vectors due to enhancements to both transfection efficiency and safety. Specifically, LCC DNA minivectors have a heightened safety profile as insertional mutagenesis is inhibited by covalently closed terminal ends conferring double-strand breaks that cause chromosomal disruption and cell death in the low frequency event of chromosomal integration. The development of a one-step, E. coli based in vivo LCC DNA minivector production system enables facile and efficient production of LCC DNA minivectors referred to as DNA ministrings. This novel in vivo system demonstrates high versatility, generating DNA ministrings catered to numerous potential applications in gene therapy and vaccine development. In the present study, numerous aspects pertaining to the generation of gene therapeutics with LCC DNA ministrings have been explored with relevance to both industry and clinical settings. Through systematic assessment of induction duration, cultivation strategy, and genetic/chemical modifications, the novel in vivo system was optimized to produce high yields of DNA ministrings at ~90% production efficiency. Purification of LCC DNA ministrings using anion exchange membrane chromatography demonstrated rapid, scalable purification of DNA vectors as well as its potential in the separation of different DNA isoforms. The application of a hydrogel-based strong Q-anion exchange membrane, with manipulations to salt gradient, constituted effective separation of parental supercoiled CCC precursor pDNA and LCC DNA. The resulting DNA ministrings were employed for the generation of 16-3-16 gemini surfactant based synthetic vectors and comparative analysis, through physical characterization and in vitro transfection assays, was conducted between DNA ministring derived and CCC pDNA derived lipoplexes. Differences in DNA topology were observed to induce differences in particle size and DNA protection/encapsulation upon lipoplex formation. Lastly, the in vivo DNA minivector production system successfully generated gagV3(BCE) LCC DNA ministrings for downstream development of a HIV DNA-VLP (Virus-like particle) vaccine, thus highlighting the capacity of such system to produce DNA ministrings with numerous potential applications.

There is an increasing demand for power converters with small size, light weight, high conversion efficiency and higher power density. Also, in many applications, there is a need for dc-to-dc converters to accept dc input voltage and provide regulated and/or isolated dc output voltage at a desired voltage level including telecommunications equipment, process control systems, and in industry applications. This thesis presents the analysis, design, simulation and experimental results of three-phase high-frequency transformer isolated resonant converters. The first converter presented is a three-phase LCC-type dc-dc resonant converter with capacitor output filter including the effect of the magnetizing inductance of the three-phase HF transformer. The equivalent ac load resistance is derived and the converter is analyzed by using approximation analysis approach. Base on this analysis, design curves have been obtained and a design example is given. Intusoft simulation results for the designed converter are given for various input voltage and for different load conditions. The experimental verification of the designed converter performance was established by building a 300 W rated power converter and the experimental results have been given. It is shown that the converter works in zero-voltage switching (ZVS) at various input voltage and different load conditions. A three-phase (LC)(L)-type dc-dc series-resonant converter with capacitive output filter has been proposed. Operation of the converter has been presented using the operating waveforms and equivalent circuit diagrams during different intervals. An approximate analysis approach is used to analyze the converter operation, and design procedure is presented with a design example. Intusoft simulation results for the designed converter are given for input voltage and load variations. Experimental results obtained in a 300 W converter are presented. Major advantages of this converter are the leakage and magnetizing inductances of the high-frequency transformer are used as part of resonant circuit and the output rectifier voltage is clamped to the output voltage. The converter operates in soft-switching for the inverter switches for the wide variations in supply voltage and load and it requires narrow switching frequency variation (compared to LCC-type) to regulate the output voltage. A three-phase high-frequency transformer isolated interleaved (LC)(L)-type dc-dc series-resonant converter with capacitive output filter using fixed frequency control is proposed. The converter operation for different modes is presented using the operating waveforms and equivalent circuit diagrams during different intervals. This converter is modeled and then analyzed using the approximate complex ac circuit analysis approach. Based on the analysis, design curves were obtained and the design procedure is presented with a design example. The designed converter is simulated using PSIM software to predict the performance of the converter for variations in supply voltage and load conditions. The converter operates in ZVS for the inverter switches with minimum input voltage and loses ZVS for two switches in each bridge for higher input voltages. / Graduate

Selecting a suitable power source, during the design process, for a stand-alone soya business unit is challenging and complex. Especially with the aim of optimizing electrical and thermal energy, as well as minimizing the life cycle cost. During the design and development of a soya business unit it was realized that a design tool is needed to assist with the decision making process when selecting a power source. Waste heat can be recovered from either or both the exhaust gas and cooling system of the power source and can be utilized in the soya process. Research of available literature revealed no design tool to assist with the decision making process of the stand-alone business unit and consequently lead to this study. This dissertation presents different possible power sources that could be utilized in supplying energy to the business unit, as well as design tools available. Advantages and disadvantages of the different power sources are discussed. The shortfalls of a number of the available design tools are also discussed. A diesel generator set was selected as the preferred power source for the business unit. Criteria for this selection included the price per kWhe generated, the ease of maintenance, the availability of the diesel generators in rural areas and the availability of diesel as a fuel. The diesel engine was characterized through experimental work for a more in depth understanding of the energy profile of the engine at part load conditions. These results were used as guidelines in the development of the design tool. The design tool was developed with the aim of being user friendly and versatile. The time intervals of the required load of the business unit are flexible. Different types of power sources and fuels can be used within the design tool. User defined heat exchangers are utilized to calculate the possible heat recovery from the power source. The design tool matches the available energy of different power sources at part load conditions with the required load profile of the soya business unit. It then eliminates power sources that would not be able to deliver the minimum required energy. The running cost is calculated for each of the remaining power sources and the power source with the minimum annualized cost, which includes capital cost, maintenance cost and fuel cost, is suggested. The design tool was verified against a base load condition of the soya business unit and the suggested power source showed a saving of 31,4% in electrical energy, an increased overall efficiency of 24,9% and a saving in annualized cost of 27,3%. The design tool can be used to optimize specific components and design options within a combined heat and power system. Sensitivity analysis can be performed with the design tool to determine various influences on the designed system. / Thesis (M.Ing. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2008.