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This study utilized two diets (25 and 35% crude protein) fed at 10 different rates to produce differences in shrimp specific growth rate which were regressed against daily digestible protein (DP) and digestible energy (DE) intake to estimate daily DP and DE requirements for sub-adult L. vannamei. Apparent DP and DE requirement for maximum growth decreased throughout the 7-week trial as shrimp size increased. Mean apparent daily DP requirement for 7.69 to 13.08-g L. vannamei fed the 25% protein diet was 6.31 g DP kg-1 BW d-1 while the 35% protein diet produced a mean apparent daily DP requirement of 8.00 g DP kg-1 BW d-1 for 8.11- to 13.79-g L. vannamei. Maintenance requirements were estimated by regressing DP feed allowances back to zero weight-gain and were 1.03 g DP kg-1 BW d-1 for shrimp fed the 25% protein diet and 1.87 g DP kg-1 BW d-1 for shrimp fed the 35% protein diet. Mean apparent daily DE requirement for shrimp fed the 25% protein diet was 402.62 kJ DE kg-1 BW d-1 while the 35% protein diet produced an apparent daily DE requirement of 334.72 kJ DE kg-1 BW d-1. Mean apparent daily DE maintenance requirements for shrimp fed the 25% protein diet was 66.23 kJ DE kg-1 BW d-1 while the requirement was 78.82 kJ DE kg-1 BW d-1 for shrimp fed the 35% protein diet. Daily DP and DE requirements were also determined by regressing whole-body protein or energy change against daily DP and DE intake and were similar to those values obtained by regressing change in body weight against daily DP and DE intake. Another component of this project involved evaluating 32 different feedstuffs for dry matter, protein and energy digestibility coefficients. Fish meal apparent crude protein digestibility coefficients as a group were higher than all other ingredient classifications except purified ingredients. Protein in 48% soybean meal and 90% isolated soybean protein were significantly more digestible than protein found in fish, animal and marine meals tested. This data will improve the quality and reduce the cost of commercial shrimp feeds.

Municipal water distribution systems are operated and maintained by utilities whose first priority is the safe and reliable provision of drinking water to consumers. The cost to move and treat water through distribution networks is significant and can account for up to 80% of a utility’s energy costs. As these networks age, operating and maintenance costs continue to increase due to higher incidences of leaks and breaks and increased pipe friction leading to higher energy use. Many utilities are considering water conservation as a strategy to reducing their energy consumption by reducing the amount of water being pumped and treated in their jurisdictions. This work studies the pumping energy response of a distribution system when water conservation strategies are implemented in small geographic areas in the network. A water conservation plan is tailored to each defined area by specifying which conservation measures are feasible to implement, desired by the customer, and are attractive to the utility based on a potential return on investment in the form of reduced electricity bills to pump and treat water. Energy intensity and energy elasticity indicators are developed to assess the mechanical energy used in a network to distribute water to end-users. A case study for the City of Kingston water distribution system is presented. The distribution system studied indicated that when water conservation strategies produced marginal water savings, the energy response was inelastic to changes in water demand. The amount of energy required to move one cubic metre of water through the network increased with higher water savings because the percent savings of water was higher than the percent savings of pumping energy. / Thesis (Master, Civil Engineering) -- Queen's University, 2013-05-31 14:20:18.363

Water infrastructure systems worldwide use large amounts of energy to operate. Energy efficiency efforts are relevant because even relatively small gains in efficiency have the potential to bring significant benefits to these utilities in terms of financial savings and enhanced sustainability and resiliency. In order to achieve higher efficiency levels, energy usage must be measured and controlled. A common tool used to measure energy efficiency in water utilities and perform comparisons between utilities is metric benchmarking. Energy benchmarking scores are intended to measure how efficient water systems are among their peers, in a simple and accurate fashion. Although many different benchmarking methods are currently used, we chose to use the segregated benchmarking scores proposed by Carlson on his research report from 2007 (Carlson, 2007). The research objective is to improve these production energy use and treatment energy use benchmarking scores by analyzing the system's particular characteristics that might skew the results, such as topology, water loss and raw water quality. We propose that benchmarking metrics should be always used within a particular context for each specific utility being analyzed. A complementary score (Thermodynamic Score) was developed to provide context on how energy efficient is the utility not only compared with other utilities, but also compared with the potential maximum efficiency the utility can reach itself. We analyzed eight utilities from Virginia to obtain production and treatment energy use benchmarking scores and also thermodynamic scores using the minimum required energy approach. Benchmarking scores were skewed in 50% of the studied utilities. This means that benchmarking scores should never be used as a black box. The thermodynamic score proved to be useful for measurement of energy efficiency of a water utility on its production phase. In addition, some utilities can detect significant financial saving opportunities using the minimum required energy analysis for production operations. / Master of Science

Text in English / Cow size influences biological efficiency of individual animals, which influences herd composition and stock flow. This in turn influences the economic efficiency of the herd. This research followed the thread from animal size, to biological efficiency, to economic efficiency for beef cattle production under a typical production system in semi-arid South Africa. Cattle were grouped into three groups namely small, medium and large cattle, with mature weights of 300kg, 450kg and 600kg respectively. The net energy requirements of individual cattle were calculated for maintenance, growth, lactation and foetal production, for each of the three sizes. Growth rates, milk yield, reproduction rates, and management practices were assumed from existing research. Next the stock flow for a herd of small, medium and large cattle were calculated from the above. Income and expenses as commonly used in the research area were calculated from the stock flow. Gross profit above allocated costs were subsequently calculated for the three herds under the above-mentioned conditions. When assuming similar reproduction and growth rates for small, medium and large mature cattle, the following results were obtained: more heads of small cattle could be held on a set resource base, but the total live weight of a herd of large cattle that could be held on the same resource base was greater. This was mostly due to proportionately lower maintenance energy requirements in the herd of large cattle. In the simulation in this study, maintenance energy requirements for the herd of large cattle was 71.2%, compared to 72.0% for the herd of medium cattle and 73.1% for the herd of small cattle. Income from the herd of small cattle was the lowest, as less kilograms of beef were available to sell. Allocated costs for the herd of small cattle were the highest, due to a large number of expenses being charged per head of cattle. As a result, the herd of large cattle were more economically efficient than their smaller counterparts. Income above allocated costs for the herds of large, medium and small cattle were R1,182,865, R1,085,116 and R946,012 respectively. Larger cattle generally have a lower reproduction rate under similar conditions. No equation exists that directly links size to reproduction rates, especially considering the vast number of variables that influences reproduction rates. However, in the form of scenarios, it could be calculated that, given a reproduction rate of 80% for mature small cattle, when reproduction rates of large cattle were 24.7% lower than that of small cattle and the reproduction rates of medium cattle were 15.4% lower than that of small cattle, the large and medium herds became less profitable than the small herd. Smaller cattle mature faster than larger cattle which provides the opportunity for early breeding. When small cattle were bred early, at 15 months, at a calving rate of only 44.5% it was more profitable than when the same cows were bred at 24 months. When medium cattle were bred at 15 months, a calving rate of 37.0% was needed to be more profitable than when they were bred at 24 months. Even when the herd of small cattle were bred at 15 months with a reproduction rate of 100%, it could still not match the profitability of the herd of large cattle bred at 24 months given the reproduction rates of all other classes of animals were similar. When the herd of medium cattle were bred at 15 months, at a calving rate of 53.7%, it matched the profit of the herd of large cattle that were bred at 24 months, when the reproduction rates of other classes were equal. Scenarios were considered were feed intake was limited. When feed was limited to a specific amount, smaller cattle were more biologically efficient and cattle with potential for small mature sizes would grow to a larger size than cattle with potential for medium and large mature sizes. When feed was limited by a factor of the calculated energy requirements of small, medium and large cattle, large cattle were more effective. This is because large cattle use proportionately less energy for maintenance, which allows more energy to be allocated to growth, lactation and foetal production. When energy was limited to an amount per unit of metabolic weight, small cattle were more efficient than medium and larger cattle in the growth and production phases. Small, medium and large cattle were equally efficient (or inefficient) in the maintenance and lactation phases. Energy requirements of cattle in South Africa are commonly calculated using the Large Stock Unit (LSU). The LSU typically overestimates energy requirements for cattle, except in the lactation phase. When using the LSU to match small, medium or large cattle to a resource base, the LSU overestimates energy requirements of large cattle proportionately more than that of small and medium cattle. This is excluding the lactation phase, where energy requirements for all three sizes are underestimated and that of large cattle underestimated proportionately more. There are more considerations when matching cow size to managerial practices. A smaller body size is a natural adaptation to a semi-arid environment and this adaptation can be expressed in different ways. The number of animals on a resource base has implications on management practices. Having more heads of cattle on a resource base increases genetic variation of the herd, allowing for genetic progress to be made faster than in herd of fewer cattle. / Agriculture and  Animal Health / M.Sc. (Agriculture)

The Bushveld Igneous Complex (BIC) in South Africa holds approximately three quarters of the world’s viable chromite ore deposits. Most chromite is used for the production of ferrochromium (FeCr), which is a relatively crude alloy. Several chromite seams exist in the BIC. The most economically viable seams are the lower group 6 (LG6), the middle group 1 and 2 (MG1 and 2) and the upper group 2 (UG2) seams. The LG and MG seams are exploited specifically for their chromium content, whereas the UG2 seam is mainly exploited for platinum group minerals (PGM). However, the upgraded UG2 chromite in the PGM tailing is increasingly being used as a feedstock for FeCr production. Many different process variations exist for FeCr production. However, the process option applied in most green and brown field FeCr expansion projects during the last two decades in South Africa has been the oxidative sintered process (also referred to as the Outotec or Outokumpu process). Notwithstanding the common application of the oxidative sintered pelletised feed technology in the South African FeCr industry, and the increased utilisation of beneficiated UG2 ore, a direct comparison of the physical properties of oxidative sintered pellets produced from UG2 with the physical properties of that produced with conventional metallurgical grade chromite ore is currently lacking in the peer-reviewed scientific literature. Therefore, the physical properties of oxidative sintered pellets produced from a typical beneficiated South African UG2 ore were compared with the physical properties of that produced with conventional South African metallurgical grade chromite ore in this study. The results indicated that the case study metallurgical grade chromite ore required 13 kWh/t more energy to mill than the case study UG2 ore prior to pelletisation, which can lead to substantial cost savings. The compressive strength of the oxidative sintered pellets of both case study ores statistically showed that oxidative sintered pellets made from UG2 ore Abstract were the same or better than those prepared from metallurgical grade chromite ore. A comparison of the abrasion strengths of the oxidative sintered pellets of both case study ores indicated that the pellets prepared from UG2 ore were superior compared to the metallurgical grade pellets. The reasons for the superior UG2 pellet strength were investigated with backscatter-, secondary electron- and elemental X-ray mapping scanning electron microscopy (SEM), which indicated that differences in crystalline structures at least partially contributed to the differences observed. Results presented here can be utilised by FeCr producers to better quantify the advantages and disadvantages associated with the use of UG2 ore for FeCr production. / MSc (Chemistry), North-West University, Potchefstroom Campus, 2014

The Bushveld Igneous Complex (BIC) in South Africa holds approximately three quarters of the world’s viable chromite ore deposits. Most chromite is used for the production of ferrochromium (FeCr), which is a relatively crude alloy. Several chromite seams exist in the BIC. The most economically viable seams are the lower group 6 (LG6), the middle group 1 and 2 (MG1 and 2) and the upper group 2 (UG2) seams. The LG and MG seams are exploited specifically for their chromium content, whereas the UG2 seam is mainly exploited for platinum group minerals (PGM). However, the upgraded UG2 chromite in the PGM tailing is increasingly being used as a feedstock for FeCr production. Many different process variations exist for FeCr production. However, the process option applied in most green and brown field FeCr expansion projects during the last two decades in South Africa has been the oxidative sintered process (also referred to as the Outotec or Outokumpu process). Notwithstanding the common application of the oxidative sintered pelletised feed technology in the South African FeCr industry, and the increased utilisation of beneficiated UG2 ore, a direct comparison of the physical properties of oxidative sintered pellets produced from UG2 with the physical properties of that produced with conventional metallurgical grade chromite ore is currently lacking in the peer-reviewed scientific literature. Therefore, the physical properties of oxidative sintered pellets produced from a typical beneficiated South African UG2 ore were compared with the physical properties of that produced with conventional South African metallurgical grade chromite ore in this study. The results indicated that the case study metallurgical grade chromite ore required 13 kWh/t more energy to mill than the case study UG2 ore prior to pelletisation, which can lead to substantial cost savings. The compressive strength of the oxidative sintered pellets of both case study ores statistically showed that oxidative sintered pellets made from UG2 ore Abstract were the same or better than those prepared from metallurgical grade chromite ore. A comparison of the abrasion strengths of the oxidative sintered pellets of both case study ores indicated that the pellets prepared from UG2 ore were superior compared to the metallurgical grade pellets. The reasons for the superior UG2 pellet strength were investigated with backscatter-, secondary electron- and elemental X-ray mapping scanning electron microscopy (SEM), which indicated that differences in crystalline structures at least partially contributed to the differences observed. Results presented here can be utilised by FeCr producers to better quantify the advantages and disadvantages associated with the use of UG2 ore for FeCr production. / MSc (Chemistry), North-West University, Potchefstroom Campus, 2014

The nutritional care and management of patients includes provision of adequate nutrition support to ensure that they attain and maintain a desirable body weight, improve nutritional status and avoid negative outcomes associated with over- or underfeeding. The success of nutrition support relies on accurately estimating energy requirements so that adequate energy and nutrients can be provided to the patient. Energy requirements are most accurately determined by measurement of energy expenditure. Most methods for doing so however are expensive, time-consuming, require trained technicians to perform them and are therefore impractical in the clinical setting. As such, prediction equations, which are easy to use, inexpensive and universally available, are commonly used to estimate the energy requirements of hospitalised patients. The accuracy of these equations however is questionable. Recently, a new portable hand-held indirect calorimeter (MedGem(tm), HealtheTech, USA), which has been promoted for its ease of use and relatively short measurement time, has been validated in healthy subjects but is yet to be validated in patients with illnesses. Weight loss and malnutrition occur commonly in patients with cancer and are often thought to be associated with disturbances in energy metabolism caused by the tumour. Minimising weight loss is an important goal for the nutritional care of patients with cancer. The ability to accurately determine the energy requirements of these patients is therefore essential for the provision of optimal nutrition support. This research project proceeded in two phases. Phase 1 aimed to determine current methods used by dietitians for estimating adult patients' energy requirements using a descriptive study. Results of this study informed phase 2, which aimed to investigate differences in energy expenditure of cancer patients compared to healthy control subjects and to compare different methods for determining energy requirements of people with cancer in the clinical setting. To address phase 1 a national cross-sectional survey of dietitians working in acute care adult hospitals was undertaken to determine their usual dietetic practice with respect to estimating patients' energy requirements. Responses to the survey (n=307, 66.2%) indicated a large variation in dietitians' practice for estimating energy requirements particularly with respect to the application of methods involving injury factors. When applied to a case study, these inconsistencies resulted in an extremely wide range for the calculated energy requirement, suggesting that there is error inherent in the use of prediction methods, which may be associated with negative consequences associated with under- or overfeeding. The types of patients for whom dietitians estimate energy requirements appears to be heavily influenced by feeding method. Initial dietetic education was identified as the main influencing factor in the choice of method for estimation of energy requirements. Phase 2 was addressed using four studies based on the same study population - a case-control study, two clinical validation studies and a measurement methods study. Patients had histologically proven solid tumours, excluding tumours of the breast, prostate and brain, and were undergoing anti-cancer therapy (n=18). Healthy control subjects were group matched to cancer patients by gender, age, height and weight from a purposive sample (n=17). Resting energy expenditure (REE) was measured by respiratory gas exchange using a traditional indirect calorimeter (VMax 229) and the MedGem indirect calorimeter. A measurement methods side-study established that steady state defined as a three-minute period compared to a five-minute period measured REE within clinically acceptable limits. REE was also predicted from a range of prediction equations. Analyses of available data found that REE in cancer patients was not significantly different from healthy subjects, with only a 10% higher REE observed in this sample of cancer patients when adjusted for fat free mass. For both cancer patients and healthy subjects the portable MedGem indirect calorimeter and all prediction equations did not measure or estimate individual REE within clinically acceptable limits compared to the VMax 229 (limits of agreement of approximately -40% to 30% for both the MedGem and prediction equations). Collectively, the results of this research project have indicated that current practical methods for determining patients' energy requirements in a clinical setting do not accurately predict the resting energy expenditure of individual subjects, healthy or with cancer. Greater emphasis should therefore be placed on ensuring intake meets requirements. For this to occur, dietetic practice should be focused on directly monitoring both patients' actual energy intake and patient outcomes, such as weight, body composition and nutritional status, to determine whether energy requirements are being met. This research has led to multiple recommendations for dietetic practice, focusing on the standardisation of education practices. Recommendations for future research address methodological improvements.

Η εξοικονόμηση ενέργειας αποτελεί τον βασικότερο πυλώνα της ενεργειακής πολιτικής κάθε χώρας. Ο κτιριακός τόμέας καταναλώνει ένα αρκετα μεγάλο ποσοστό της συνολικής απιτούμενης ενέργειας σύμφωνα με την Ευρωπαική Ένωση γι'αυτό μελετάμε σε πρώτο στάδιο την ενεργειακή κατανάλωση ενός κτιρίου σύμφωνα με μια κοινά αποδεκτή μεθοδολογία προερχόμενη από την Ευρωπαική Επιτροπή (CEN), η οποία στηρίζεται σε επιστημονικά δεδομένα και στατιστικές μελέτες για να προσεγγίζει ένα βέλτιστο αποτέλεσμα. Επιπλέον, μελετάμε πως συμβάλλει ο τύπος κτιρίου, οι κλιματολικές συνθήκες της περιοχής όπως και τα συστήματα θέρμανσης-ψύξης, φωτισμού και ζεστού νερού χρήσης στην κατανάλωση ενέργειας του κτιρίου. Τέλος δημιουργήσαμε ένα πρόγραμμα όπου με αντικατάσταση των συστημάτων που αναφέραμε παρουσιάζεται (και σε γραφικό περιβάλλον) τόσο η ενεργειακή εξοικονόμηση όσο και η εξοικονόμηση χρημάτων. / This diploma thesis focuses on the consumption of buildings, becayse an ever icreasing persentage of total energy is required to cover domestic needs. Firstly,we calculate the energy requirements of a building according to a common methodology derived from the European Commission (CEN),with which we have an otimal result becase it is based on scientific thought and statistics.Moreover, the energy that is finally consumed depends on the type of building, the climatic conditions of the area and the heating, cooling, lighting and water-heating systems that are used.The research, on how all the above, contribute to the energy consumption, as well as the possibility of the comparison if the above systems are replaced with more economical ones, were the reasons to create a program(including grafic interface).

Sweden has formulated ambitious energy goals which signify that by year 2050 the energy usage should be halved. One of the objectives is the reduction of energy usage by 20% by year 2020 and that it should be compared to the usage of energy from 1995. In parallel with increased energy requirements for buildings the demand on housing conservation, by highlighting also buildings from the last 50 years as part of the building heritage, continues to enhance, which in theory means that there is a conflict between these. The law will never be able to point out unique buildings and PBL (planning and building act) is not especially concrete. The National Housing Board has tried to make this more concrete by the new BBR regulations though there are still an enormous variety of interpretations. This report deals with the conflict between conservation requirements and additional insulation of the building envelope and is limited to multi-residential buildings built between the years 1945 and 1975. It is the stock with the greatest energy consumption and that is where the big challenge lies. The question is whether in practice it is no conflict between conservation requirements and additional insulation of the building envelope and what it in this case depends. With the support of background facts, interview questions were formulated for different participants. By interviews with property-owners, municipalities and other partners it has been shown that the creation of zoning determines whether a property has been preserved. In municipalities with a metropolitan character the interest in conservation issues are the greatest and Stockholm municipality distinguishes itself, providing significant space in regards to this subject. The smaller municipalities do not believe in that the preservation of our multi-residential buildings are central but that there lies a greater problem in areal density and that eventually great portions of the genuine country will disappear. Only in isolated cases, conservation requirements became an obstacle in performing façade renovations. Property owners are interested in the conservation issue; however, it must be weighed against the economic condition and therefore is it in sight of what is a good conservation. / Sverige har formulerat ambitiösa energimål som innebär att till år 2050 ska energianvändningen halveras, där ett delmål är minskning med 20 % till år 2020 och det ska jämföras med energianvändningen från år 1995. Parallellt med ökade energikrav för byggnader ställs det även allt högre krav på husens bevarande, vilket teoretiskt innebär att det ligger en konflikt mellan dessa. Lagen kommer aldrig att kunna peka ut unika byggnader och PBL (plan- och bygglagen) är inte särskilt konkret. Nu har Boverket försökt konkretisera genom nya BBR reglerna, men det finns ändå oerhört mycket plats för tolkningar. Denna rapport behandlar konflikten mellan bevarandekrav och tilläggsisolering av klimatskalet och är begränsad till flerbostadshus byggda mellan åren 1945 och 1975. Det är det bestånd som har störst energiåtgång och det är där den stora utmaningen ligger. Frågan är om det i praktiken ligger någon konflikt mellan bevarandekrav och tilläggsisolering av klimatskalet och vad den i så fall beror på? Med stöd av bakgrundsfakta har intervjufrågor formulerats till olika aktörer. I intervjuer med fastighetsägare, kommuner och övriga parter har det visat sig att utformningen av detaljplanen är avgörande för om en fastighet kan bevaras. I kommuner med storstadskaraktär är intresset för bevarandefrågorna störst och Stockholms kommun utmärker sig, där dessa frågor getts störst utrymme. De mindre kommunerna anser inte att bevarandet av våra flerbostadshus är centralt utan där är det ett större problem att områdena förtätas och att på sikt stora delar av den genuina landsbygden kommer att försvinna. Endast i enstaka fall har bevarandekraven blivit ett hinder för att utföra fasadrenoveringar. Fastighetsägare är intresserade för bevarande frågan men detta måste vägas mot ekonomiska förutsättningar och därför skiljer det i synen om vad som är ett gott bevarande