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Lobster Sampling TrapFike, William H. January 2007 (has links) (PDF)
No description available.
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Appraisal of experimental performance and modelling of an on-farm dairy milk bulk cooler: Fort Hare Dairy Trust, South AfricaMhundwa, Russel January 2017 (has links)
South Africa contributes approximately 0.5 percent to the total world milk demand and is the third largest producer of fresh cow milk in Africa after Sudan and Kenya. In comparison to any other enterprise, the cost of milk production is influenced by numerous factors, that in turn affect the profitability of the farm enterprise; however one of such factors is high electricity cost. In this regard, there is need for efficient operation of the milk processing plant at all stages and at the same time maximising on product quality and minimising on the cost of production including energy. At the dairy farm, milk handling mainly commences as the milk leaves the cow udder at 35°C–37°C and must be cooled rapidly to a storage temperature of 4°C in a bid to stop microbial activity. The cooling of the milk can be done directly by the bulk milk cooler (BMC) from 37°C to the required storage temperature of 4°C or it can be done successively through pre-cooling. The process of pre-cooling involves the use of a heat exchanger where in most instances the plate heat exchanger (PHE) is used as the pre-cooler (PC) thereby leading to energy savings in a dairy facility. Cooling of milk involves significant amount of energy and it could account for about 20 percent of the total energy consumed on a farm. The aim of the research was to develop mathematical models that could be used to predict the electrical energy performance and capture the cooling saving of an on-farm direct expansion bulk milk cooler (DXBMC) during the milk cooling process. Accordingly, data acquisition system (DAS) was designed and built to accurately measure the power consumption of the BMC, temperature of raw milk, room temperature, temperature of cold water, relative humidity and ambient temperature. The volume of milk produced per day was extracted from the daily records on the farm. In addition, the temperature sensors were connected to a four channel HOBO data loggers which were configured to log at every five-minutes interval. The results were analysed and the mathematical models were developed using MATLAB. The statistical Toolbox in MATLAB was used to rank the predictors according to their weight of importance using the ReliefF Algorithm test. The results showed that on average, the daily electrical energy consumed by the BMC at the two milking times was higher during the peak period (127.82 kWh and 93.86 kWh) than the off-peak period (48.31 kWh and 43.23 kWh). On average, the electricity used for cooling of milk on the dairy farm was 17.06 kWh/m3 of milk. The average monthly electricity used per cow on the farm was 8.03 kWh/cow which translated to an average of 0.26 kWh/cow/day The average specific energy consumption of the cooling system per litre of milk cooled was 0.02 kWh/L and was almost constant throughout the whole period of monitoring. Furthermore, the BMC was able to cool 57.33 L/kWh during the off-peak period which increased by 7.7 percent to 62.13 L/kWh during the peak period. Furthermore, mathematical models represented as multiple linear regression (MLR) models were built and developed using the experimental data. The developed mathematical models had good agreement with the experimental data as evidenced by the correlation coefficients of 0.922 and 0.8995 along with 0.935 and 0.930. The ReliefF Algorithm test revealed that the volume of milk was the principal contributor to the energy consumption of the BMC for both the morning (AM) and afternoon (PM) milking period. The Relative Prediction Error (RPE) was used to evaluate the suitability of the developed models. In this light, the AM off-peak model had RPE of 18.54 percent while the PM off-peak model had 14.42 percent. In addition, the AM peak and PM peak models had RPE of 19.23 percent and 18.95 percent respectively. This suggested that the MLR models for the off-peak and peak milking periods (both AM and PM) had acceptable prediction accuracy since the RPE values were between 10 percent and 20 percent. The findings from the experimental study showed that the coefficient of performance (COP) of the AM milking period was higher (2.20) than that of the PM milking period of the BMC (1.93). Increase in the milk volume led to an increase in the COP such that the peak period with higher milk volumes recorded a high COP increase of 12.61 percent and 19.81 percent for the AM and PM milking periods respectively.
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Optimising the performance of domestic wall mounted space comfort heaterNjofang, Jerome Tangkeh January 2016 (has links)
Thesis (MTech (Mechanical Engineering))--Cape Peninsula University of Technology, 2016. / The performance of a wall Mounted space comfort heater has been studied with respect to the geometry of its mounting condition. Tests were conducted in a laboratory with the heater positioned at various heights from the floor and the channel that is created by the various gaps with the wall on which the heater was mounted. Tests were also performed with the heater mounted on the wall whose emissivity was adjusted to low, medium and high values as well as placing insulation material on the wall directly behind the heater. The outcome of the experiments revealed an acceptable geometry of the heater’s mounting at least 200 mm above the floor, and 50 mm off-set from the wall. The results of the heater mounted against the wall revealed a drop in performance as compared to the heater’s “benchmark” performance when it was freely standing on the floor of the laboratory; with an efficiency of about 41% (almost evenly shared by each face). This efficiency, which is based on the convective heat transfer generated by the heater’s warm/hot surfaces, is relative to the electrical energy input and it dropped when the heater was mounted against a grey wall to around 35%, of which only 26% was produced inside the channel. The heat transfer by radiation from the heater’s surface is treated as net loss to the walls of the room/enclosure.The performance of the heater when mounted against the wall improved almost to the benchmark value when the wall behind the heater was made refelective (low emissivity). It is recommended that further research should be undertaken to thoroughly investigate the “mode” of heat transfer, by the induced flow through the channel, in a more formal or scientific modelling approach.
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Smart electricity metering : hardware development and socioeconomic aspectsLewis, Richard Peter January 2012 (has links)
No description available.
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An analysis of hospital temperature maintenance and tray assembly systems : an industry projectDeWerff, Frank John 01 June 1976 (has links)
Every hospital, private or public, profit or nonprofit, no matter the size, has the task of feeding its patients three times a day plus nourishments. The meals must be served during a short period of time to patients in their rooms which are spread throughout the hospital. The meals must be therapeutically balanced, attractive, the hot foods hot and the cold foods cold, and they must be nutritious. The meals in a hospital differ from those served in restaurants in that all of the courses are served at one time which means that there is greater importance placed on temperature maintenance. Considering that most hospitals offer a selective menu, the task is quite unique and challenging.
Hospitals, profit or non-profit are conscious of cost, efficiency, and patient satisfaction. Therefore, the selection of a system to assemble and deliver meals to the patient is of the utmost importance.
The purpose of this study is to identify and compare assembly and temperature maintenance and delivery systems currently available; in order to make available information for those who are planning systems and for those who are learning about these systems.
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Analysis of restricted earth fault relay application within a shunt capacitor bank design impacting on protection stabilityMinkley, Warick January 2013 (has links)
This research is aimed at analyzing the performance of the restricted earth fault relay used on a 400kV capacitor bank scheme used on the Eskom Transmission network. After the commissioning of two Capacitor Banks using the above mentioned scheme design the plant was energized. As a result of the energization the Shunt Capacitor Bank (SCB) then experienced spurious trips. The cause of the trips was found to be the operation of the restricted earth fault relay. In this research project, restricted earth fault protection on SCBs in the Eskom Transmission environment will be the area of interest. The proposed research will analyze the current SCB protection scheme in service specifically looking at the restricted earth fault circuit design and relay performance. An equivalent model of the SCB from primary plant perspective based on theory will be derived. Recording and analyzing of Comtrade transient waveforms respectively, when the bank is nergized, will be done in order to provide a reference base to work from. Manual alculations of various parameters from the derived model including transient inrush currents and fault currents will be performed to access applicable scheme parameters. Further calculations will include the voltage setting for the restricted earth fault relay. As a result of the analysis a recommendation will be made on a viable solution or a revised design will be put forward, based on the results, to improve the scheme’s performance. The protection scheme is used on the two 400kV 100MVAR capacitor banks 11 and 12 at Hydra Substation.
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Best cost country sourcing : optimising the value of conveyor belts for coal mining companiesViljoen, Alida Maria 20 October 2014 (has links)
M.Com. (Business Management) / Background Best cost country sourcing is a relatively new concept and not many organisations are utilising this specific process nor are they optimising this as their sourcing strategy. Best cost country sourcing is one of the most profound sourcing processes available, and it has the ability to increase an organisation’s efficiency and effectiveness if implemented correctly. Purpose The purpose of this study is to determine if best cost country sourcing should be used as an alternative to local sourcing. It includes aspects of the best cost country sourcing process as well as its risks and advantages. Research method The dissertation analyses the process of best cost country sourcing and the effect it has on an organisation’s sourcing strategy. To achieve this understanding it is necessary to do a qualitative investigation, which is the reason a qualitative research was used as the research methodology in this dissertation. Conclusion Pursuing the process of best cost country sourcing requires a lot of dedication and implementation time. It is a complicated process and no two situations will be alike. Each organisation would need to determine the advantages, risks and challenges which they will encounter with best cost country sourcing. Organisations would also need to determine the best cost countries, as well as the criteria they would need to use in selecting potential suppliers.
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An engineering management analysis of communication management systems in an organization that supplies the mining industryMeid, Andreas 26 June 2015 (has links)
M.Ing. (Engineering Management) / Broadly speaking, communication forms an integral component of everyone’s daily activities, be it on a personal level amongst family and friends, or in a professional environment. In many instances, the ability of project teams to communicate effectively and efficiently is taken for granted by project managers, which can result in projects being late or incomplete. However, the importance of Project Communications Management is evident in the fact that the Project Management Institute (PMI) dedicates a chapter to Project Communications Management in the PMBOK® Guide. The current research seeks to understand what effect communication has on a project, and how it can be successfully managed during a project. The research in the form of a case study investigated the state of communications within a project department, with the aim of identifying whether a lack of communication during a project is a contributing factor to projects being late or incorrect. The department in question is responsible for supplying the mining industry with critical conveyor drive equipment. The case study research was conducted utilizing the procedure outlined in the Organizational Project Management Maturity Model (OPM3®). The research found that certain areas in the department lacked the basic requirements for effective communications, and that a lack of communication between various stakeholders during a project could negatively influence the success of a project. These findings were compared to those of independent research by the PMI into global trends of project communications. The important aspects relating to Project Communication Management were discussed, and a workable solution to the problem was proposed. It was found that by implementing a communication plan in the department, and encouraging a culture of open and honest communications, the organization can expect to see an improvement in project success.
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The Experiences of Younger Adults (18-40 Years) Living with an Implanted Cardioverter Defibrillator (ICD): A DissertationMcDonough, Annette 01 May 2007 (has links)
Sudden cardiac death (SCD) is responsible for 300,000 deaths in the United States each year. Of these 300,000 deaths, 3,000-5,000 are younger adults (18-40 years) (American Heart Association (AHA), 2005; Sudden Arrhythmia Death Syndromes Foundation (SADS), 2005). Implanted cardioverter defibrillators have become the treatment of choice for individuals with life threatening arrhythmias (Cannom Prystowsky, 2004; Glikson & Friedman, 2001; Josephson, Hein, & Wellens, 2004). Although this life sustaining technology has been found to be effective in terminating life threatening arrhythmias, adjustment to an ICD may be difficult for some patients (Ganz, 2004). Few studies have investigated how younger adults manage life with an ICD (Sears, Burns, Handberg, Sotile, & Conti, 2001). It has been reported that older adults view the ICD as an extension of life, whereas, younger ICD recipients associate the ICD with significant life changes, body image concerns, and decreased independence (Arteaga & Windle, 1995).
The purpose of this study was to describe the day-to-day experiences of younger adults (18-40 years old) [N = 20] living with an implanted cardioverter defibrillator. A qualitative descriptive design was used with naturalistic inquiry guiding data collection, management, and analysis. Using open-ended, in-depth interviews, younger adults were asked to describe their life after ICD implantation, physiological or psychosocial issues related to ICD implantation, and strategies used to manage life with an ICD. Data were managed using NVIVO software and analyzed using content analysis. The results revealed an overarching theme, A cautious transition to a new normal, with five subthemes: Initial diagnosis: anxiety and concern; Caution, awareness, and security: daily life with an ICD; Childbearing: passing my disease to my children; Financial concerns; and Strategies for living with an ICD: be positive and live life to the fullest.
This study presented some of the unique developmental and transitional issues that younger adults with ICDs are facing and strategies they used to assist in adaptation to life with an ICD. Their experiences can provide the basis for intervention programs that are developmentally sensitive and age-specific.
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An evaluation of the science materials accessible in the four white senior high school libraries of Broward CountyUnknown Date (has links)
"The American public is being inundated by newspaper and magazine articles conveying the message that schools in the United States must develop and improve their science curricula if the nation is to compete successfully with ideologies inimical to that taught in this country. Some of these articles concern themselves with immediate remedies, such as more frequent testing of scientific aptitude and progress from the seventh grade on, and providing more teaching materials for all grade levels. Others analyze the present trend of awarding large numbers of college scholarships to high school students. A few of the articles are more philosophical in content: some of these, for example, decry the national habit of secrecy in scientific research. This study has grown out of this widespread concern. It seems reasonable to assume that one significant factor in determining the quality of instruction in science in a senior high school is the adequacy of the instructional materials accessible to the students and teachers of that school. It has seemed timely and pertinent, then, to examine such materials in the four white senior high schools of Broward County and to evaluate their strengths and weaknesses"--Introduction. / "August, 1958." / At head of title: Florida State University. / Typescript. / "Submitted to the Graduate Council of Florida State University in partial fulfillment of the requirements for the degree of Master of Arts." / Advisor: Sara K. Srygley, Professor Directing Paper. / Includes bibliographical references (leaves 32-33).
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