Showing items 1 - 20 of 34

Your selections:

Master’s of engineering management : graduation rates lagging behind growth rate

- Marnewick, A., Pretorius, J.H.C.

Impact of circuit-breaker maintenance on life-cycle cost comparison for fixed and magnetically controlled reactors

- Mbuli, Nhlanhla, Nkosi, Sphiwe, Mashego, Lehlohonolo, Pretorius, J.H.C.

Residential solar water heating - measurement and verification case studies

- Chan Wing, S.N., De Canha, D., Pretorius, J.H.C.

  • Authors: Chan Wing, S.N. , De Canha, D. , Pretorius, J.H.C.
  • Date: 2016
  • Subjects: Solar irradiation , SWHs across country , IPMVP
  • Language: English
  • Type: Conference proceeding
  • Identifier: http://hdl.handle.net/10210/92075 , uj:20182 , Citation: Chan Wing, S.N., De Canha, D. & Pretorius, J.H.C. 2016. Residential solar water heating - measurement and verification case studies.
  • Description: Abstract: South Africa is currently experiencing an electricity crisis. This, combined with the high levels of solar irradiation as well as the power utility’s need to reduce the country’s peak demand through DSM (Demand Side Management), has promoted the installation of solar water heaters (SWHs) in homes across the country. This paper presents three case studies which were M&V’d according to the IPMVP (International Performance Measurement & Verification Protocol). The methodology used does not require baseline measurements since the baseline is calculated from continuous measurements of thermal energy delivered by the newly installed SWHs and estimation of standing losses of the replaced electric water heater (EWH). This allows the homeowner to go ahead with the installation of the SWH without waiting for M&V to establish a baseline for the EWH which is being replaced. This method is preferred by homeowners and the DSM utility alike, since the installation of the SWH is not delayed by M&V. A measurement system including an electric power meter, inlet and outlet water temperature probes, ambient temperature probe, flow meter and GSM modem were developed to measure the service level and performance of the SWH. This measurement system along with a method for modelling the usage of an EWH are crucial to the M&V methodology employed. This paper describes the type of systems investigated, the M&V metering, M&V methodology, and the payback period of each system. The sensitivity of the savings with respect to EWH standing losses is investigated. This case study provides valuable information for those interested in studying or performing M&V on SWHs.
  • Full Text:

Energy savings reporting and uncertainty in measurement & verification

- Akinsooto, O., Pretorius, J.H.C., De Canha, D.

  • Authors: Akinsooto, O. , Pretorius, J.H.C. , De Canha, D.
  • Date: 2014
  • Subjects: Energy savings , International Performance Measurement and Verification Protocol
  • Type: Article
  • Identifier: uj:4990 , http://hdl.handle.net/10210/13125
  • Description: This paper provides more detailed information on the application of the International Performance Measurement and Verification Protocol (IPMVP) guideline in the determination and reporting of energy savings. It stresses the need, the importance and an approach that can be used to report energy savings accurately in Measurement and Verification (M&V). The paper focusses on the fundamentals and the applications of the IPMVP in the determination and reporting of energy savings that result from energy efficiency intervention. The methodology applied here can be used to ensure complete compliance with the IPMVP guideline.
  • Full Text:

Effectiveness of economic incentives on clients’ participation in health and safety programmes

- Musonda, I., Pretorius, J.H.C.

  • Authors: Musonda, I. , Pretorius, J.H.C.
  • Date: 2015-06
  • Subjects: Economic incentives , Health and safety programmes , Construction industry - Safety measures , Occupational health and safety
  • Type: Article
  • Identifier: uj:5138 , ISSN 1021-2019 , http://hdl.handle.net/10210/14105
  • Description: The use of economic incentives to improve health and safety (H&S) performance in the construction industry in general has been investigated by various scholars. However, few studies have looked at the impact of economic incentives on construction clients, especially in the developing world. This paper reports findings on the feasibility of incentives to influence construction clients to perform on H&S. The investigation was conducted using a Delphi technique to determine the impact significance of economic incentives or disincentives on construction clients’ H&S performance. A panel of experts in construction H&S was assembled from most regions of the world. A three- round iterative Delphi study aimed at establishing consensus from the expert panel was then conducted. The study found that economic factors have critical impact significance on clients’ H&S performance, and that clients were ‘very likely’ to implement various H&S elements as a result of the economic incentives and or disincentives. There is little research on the use of incentives to influence construction clients’ H&S performance and the effectiveness of such incentives. This gap in literature, and the need for improvement in construction H&S performance, motivated the current study. Therefore it was necessary to investigate specifically the extent to which economic incentives could be used to influence construction clients to become involved in H&S programmes. Economic incentives are considered to be a proactive way of improving H&S performance among other key parties, such as employees in the construction industry. The paper reports on the findings from an analysis of the impact significance of economic incentives on clients. It underscores the point that economic incentives or disincentives for construction clients are necessary to encourage them to actively participate in H&S programmes, hence resulting in performance improvement.
  • Full Text:

Increasing the capacity of transmission lines via current uprating: an updated review of benefits, considerations and developments

- Ntuli, Mavula, Mbuli, Nhlanhla, Motsoeneng, Lethoko, Xezile, Ronald, Pretorius, J.H.C.

Effects of culture on project management contributing to the success of managing culturally diverse engineering teams in a global environment

- Meyer, L.L., Pretorius, J.H.C., Pretorius, L.

Power transformer failure management on the Eskom distribution network in Limpopo

- Sako, M.M., Wessels, A., Pretorius, J.H.C.

Applying preventive and predictive best practice on plant maintenance

- Tshabuse, F., Pretorius, J.H.C.

  • Authors: Tshabuse, F. , Pretorius, J.H.C.
  • Date: 2016
  • Subjects: Predictive , Preventive , Maintenance
  • Language: English
  • Type: Article
  • Identifier: http://ujcontent.uj.ac.za8080/10210/363275 , http://hdl.handle.net/10210/214779 , uj:21323 , Citation: Tshabuse, F. & Pretorius, J.H.C. 2016. Applying preventive and predictive best practice on plant maintenance.
  • Description: Abstract: Quite often in the industrial environment engineers are required to justify the addition or change of equipment when companies venture into investing in capital to increase production capacity or improve efficiency. Aged and outdated machinery and equipment are at times not economical to re-fabricate due to the improvement in manufacturing methods and obsolescence of old technology. Maintenance of machinery is often not done as it should be to achieve optimum availability where policies don’t exist. Technological improvement has resulted in less robust, advanced and often more complex designs where modern technology replaces older designs making the old designs more expensive to produce in some cases. As a consequence the re-fabrication of old equipment becomes difficult to justify with the high cost. The maintenance cost of previous equipment also does not compare to modern equipment and negatively affects the competitiveness of organisations against their peers that utilize modern methods. The solution to staying competitive is to re-design, upgrade equipment, change maintenance policy or introduce technology. This research will highlight methods that can be utilized to ensure that the reliability of equipment remains at an acceptable level and also show evidence of improvement in reliability of equipment due to re-design and through continuous improvement initiatives. A case study for design and continuous improvement efforts with primary and secondary data sourced from Everite Building Products a manufacturer of fibre cement products is used and presented. The results confirm that the sustained reliability of equipment depends on the efforts by the user to keep equipment reliable through methods supporting predictive and preventive maintenance.
  • Full Text:

Total quality management adoption by process engineering design firms in South Africa

- Njenge, L., Vermeulen, Andre, Pretorius, J.H.C.

  • Authors: Njenge, L. , Vermeulen, Andre , Pretorius, J.H.C.
  • Date: 2015-06-08
  • Subjects: Product quality , Total quality management , Process engineering - South Africa
  • Type: Article
  • Identifier: uj:5133 , ISBN 9781775921110 , http://hdl.handle.net/10210/14099
  • Description: The study investigates the effects of Total Quality Management (TQM) implementation on process engineering design firms. Secondly, the study investigates the extent of TQM adoption by South African process engineering design firms. Lastly, the study investigates the perceived importance of TQM principles. The study reveals that 70% of the firms which participated in the survey have formally adopted TQM while 30% have not. Although the firms which have not formally adopted TQM are implementing TQM principles, they have not been able to implement the principles as well as the firms which have formally adopted TQM. It also reveals that TQM implementation improves employee satisfaction, customer satisfaction, and financial performance while providing a vision that channels the entire organisation towards improvements in product quality and customer†related performances
  • Full Text:

Cost sustainability of TFR electric locomotives operating on the Natal Corridor

- Makhanya, B.B.S., Mathew, R., Nel, H., Pretorius, J.H.C.

Utilising high and premium efficiency three phase motors with VFDs in a public water supply system

- Van Rhyn, P., Pretorius, J.H.C.

  • Authors: Van Rhyn, P. , Pretorius, J.H.C.
  • Date: 2015-05-13
  • Subjects: Centrifugal pump systems , Energy efficiency , Variable frequency drives
  • Type: Article
  • Identifier: uj:5107 , ISBN 978-1-4799-9978-1 , http://hdl.handle.net/10210/13929
  • Description: The increased reliability and ultimately reduced life cycle cost of high and premium efficiency three phase motors in a process control application is discussed. The reduced energy consumption of these motors is evaluated in a public water system case study under variable frequency conditions. The importance of the consideration of a combined system, which includes variable speed control, motor and load - as opposed to only replacing with high efficiency motors for energy saving purposes - is practically observed and reported on. The paper reports on the marginal improvement in energy consumption at reduced supply frequency for motor replacement only (not surprising) but a very impressive 46% saving in energy consumption by controlling pumped water at a reduced but constant delivery rate.
  • Full Text:

A refined baseline methodology for large scale lighting retrofit projects

- Mvudi, Y., Chan Wing, S.N., Pretorius, J.H.C., Beya, M.M., Ndlovu, S.M.

  • Authors: Mvudi, Y. , Chan Wing, S.N. , Pretorius, J.H.C. , Beya, M.M. , Ndlovu, S.M.
  • Date: 2016
  • Language: English
  • Type: Conference proceeding
  • Identifier: http://hdl.handle.net/10210/92067 , uj:20181 , Citation: Mvudi, Y. et al. 2016. A refined baseline methodology for large scale lighting retrofit projects.
  • Description: Abstract: The residential sector is one of the major consumers of energy produced in the world. According to International Energy Balances (IEA, 2013), the residential sector demand represents about a quarter of the primary energy used in the world. Therefore, most energy efficiency programmes targeting large savings on a national or regional level pay particular attention to the opportunities in the residential sector. Lighting retrofitting on a large number of sites constitutes one of the most used strategies of energy conservation in the residential sector. However, given the large number of sites involved in this type of project, conventional measurement and verification (M&V) techniques based on the audit of each site, are not cost effective. Often, a statistical assessment approach based on the audit of a limited number of sites is the methodology used to mitigate the cost and the logistical challenges associated with the project. The major challenge in projects of this nature is to accurately estimate the energy consumption of a large number of sites using the measurement performed on a sample of sites selected from the overall population. In this research, baseline methodologies used in a selected number of light retrofitting projects have been analysed and, based on the observations made during this analysis, some improvements are suggested. The proposed methodology has been tested on a number of residences located on the premises of the University of Johannesburg. This paper describes the existing baseline methodologies and presents the improvements suggested to enhance the credibility of M&V results. The key results of the experimental phase of this project are also presented in this paper.
  • Full Text:

Reliability based planning methodology for feeder automation

- Mavuso, T.B., Wessels, A., Pretorius, J.H.C.

Negative energy impacts in the absence of proper baseline studies - a South African case study

- Pretorius, J.H.C., Van Rhyn, P., De Canha, D.

  • Authors: Pretorius, J.H.C. , Van Rhyn, P. , De Canha, D.
  • Date: 2016
  • Subjects: Measurement and verification , Energy efficiency , Underground ventilation
  • Language: English
  • Type: Conference proceedings
  • Identifier: http://ujcontent.uj.ac.za8080/10210/368139 , http://hdl.handle.net/10210/213583 , uj:21171 , Citation: Pretorius, J.H.C., Van Rhyn, P & De Canha, D. 2016. Negative energy impacts in the absence of proper baseline studies - a South African case study.
  • Description: Abstract: Energy Conservation projects have become a focus area throughout the world in an attempt to reduce greenhouse gasses. These projects encompass various energy efficient technologies of which the retrofit of old technologies with new technology has become a common phenomenon. Energy savings are usually quantified by comparing actual post-retrofit energy consumption levels with baseline levels representative of the preretrofit status quo, adjusted for changes in energy drivers (e.g. weather). Baseline adjustments during energy conservation projects are of the utmost importance if operating conditions, occupancies, ambient temperatures, production levels and other factors have changed between the baseline period and the postretrofit period. During a recent case study in South Africa, an HVAC retrofit was done on a multistorey building where old technology air-conditioners were replaced with heat pump based units with inverters. To the disappointment of the landlord, the post energy measurements exceeded the baseline energy consumption by approximately 12% without any changes in operating conditions. This paper illustrates the catastrophic effects when an energy efficiency project is accelerated to the implementation stage without due consideration of operating conditions during the pre-implementation stage. A qualitative analysis prior to baseline establishment is proposed.
  • Full Text:

Productivity management in the South African civil construction industry – factors affecting construction productivity

- Bierman, M., Marnewick, A., Pretorius, J.H.C.

  • Authors: Bierman, M. , Marnewick, A. , Pretorius, J.H.C.
  • Date: 2016
  • Language: English
  • Type: Article
  • Identifier: http://ujcontent.uj.ac.za8080/10210/383857 , http://hdl.handle.net/10210/215348 , uj:21411 , Citation: Bierman, M., Marnewick, A & Pretorius, J.H.C. 2016. Productivity management in the South African civil construction industry – factors affecting construction productivity.
  • Description: Abstract: Labour productivity in South Africa is at one of its lowest levels. During 2014 the civil construction industry contributed only 3.5% to the GDP of South Africa. It is faced with challenges such as an industry environment that is increasingly competitive, and organisations in the civil industry that experience financial difficulties, such as low profit margins. An industryspecific survey, using a questionnaire, was conducted to ascertain the perceptions of industry professionals regarding factors which have an impact on productivity. A literature study was done to identify the factors that have an impact on construction productivity, based on a global perspective. From the literature study, 12 studies were identified, and a benchmark was set with which to compare the findings of the research questionnaire. To obtain the relevant information through the questionnaire, a selective sampling process was used, as the focus of the research required a specific group of individuals who were involved in the management of projects in the civil construction industry. Two civil engineering organisations, the South African Forum of Civil Engineering Contractors and the South African Institution of Civil Engineering, were contacted to assist with the distribution of the questionnaire. The questionnaire consisted of 51 factors which the industry professionals had to rate, based on their experience. These factors had to be rated with the use of a 0–4 Likert scale, based on two specific questions: (1) What impact does the factor have on construction productivity? (2) What is the frequency of occurrence of the factor? A total of 40 questionnaires were completed by the industry professionals. Thereafter the ranking of the factors was calculated with the use of the relative importance index.
  • Full Text:

Establishing the causes of delays in Eskom construction projects

- Kgosi, T.D., Marnewick, A.L., Pretorius, J.H.C.

  • Authors: Kgosi, T.D. , Marnewick, A.L. , Pretorius, J.H.C.
  • Date: 2018
  • Subjects: Construction delays , Project management activities
  • Language: English
  • Type: Article
  • Identifier: http://hdl.handle.net/10210/288204 , uj:31232 , Citation: Kgosi, T.D., Marnewick, A.L. & Pretorius, J.H.C. 2018. Establishing the causes of delays in Eskom construction projects.
  • Description: Abstract: The construction industry is notorious for project failure, which could be attributed to a multitude of reasons, which includes costs and time overrun. The generalized construction term for time overrun is referred to as delay. Delays in construction projects are caused by various aspects of project management and this research aims to determine the causes of de-lays in the South African construction industry, fo-cused around the constructions of Eskom capacity expansion projects. The motivation for conducting this study is to improve the knowledge of project man-agers and the project management society about the delays identified in the South African construction pro-jects. Top 20 common causes of delays were derived from the 38 delays found in the literature. The highest top 5 rated causes of delays were selected for discus-sion. The Project Management Body of knowledge ac-tivities were studied and selected with the aim of man-aging or resolving the identified delay causes.
  • Full Text:

The correlation between TQM Constructs and supplier performance

- Sukdeo, Nita, Vermeulen, Andre, Pretorius, J.H.C.

An integrated systems approach to risk management within a technology-driven industry, using the design structure matrix and fuzzy logic

- Barkhuizen, W.F., Pretorius, J.H.C., Pretorius, L.

  • Authors: Barkhuizen, W.F. , Pretorius, J.H.C. , Pretorius, L.
  • Date: 2012
  • Subjects: Fuzzy logic thinking , Risk management
  • Type: Article
  • Identifier: uj:4661 , ISSN 2224-7890 , http://hdl.handle.net/10210/10034
  • Description: Risk interactions exist within a system and its sub-systems, between functional and physical elements in various dimensions such as spatial interaction, information exchange, material transfer, and energy exchange. These interactions are of a multi-dimensional complexity, and thus are not sufficiently interpreted using conventional management tools. Alternative system representation and analysis techniques are proposed – in particular the design structure matrix (DSM) and fuzzy logic thinking – to quantify the risk management effort necessary to deal with uncertain and imprecise interactions. A cement grinding plant case study is used to elaborate on the risk management methodology
  • Full Text:

An approach to innovation in risk systems

- Barkhuizen, W.F., Pretorius, J.H.C., Pretorius, L.

  • Authors: Barkhuizen, W.F. , Pretorius, J.H.C. , Pretorius, L.
  • Date: 2011
  • Subjects: Risk interactions , Fuzzy logic thinking
  • Type: Article
  • Identifier: uj:6043 , http://hdl.handle.net/10210/10449
  • Description: Risk interactions exist between functional and physical elements within a system and its sub-systems in various ”dimensions” such as spatial interaction, information exchange, material transfer, energy exchange etc. The interactions are of a multi-dimensional complexity that cannot be sufficiently interpreted using conventional management tools (PERT, Gantt and CPM methods). Alternative system representation and analysis techniques are proposed, in particular the design structure matrix (DSM), and fuzzy logic thinking to quantify the risk management effort necessary to deal with uncertain and imprecise interactions. A Cement Grinding Plant case study is utilized to elaborate on the risk management methodology.
  • Full Text:
  • Disclaimer
  • Privacy
  • Copyright
  • Contact