Issue 1, 2015 South African Journal of Industrial Engineering - Volume 26,
Volume 27 (2016) Volume 26 (2015) Volume 25 (2014) Volume 24 (2013) Volume 23 (2012) Volume 22 (2011) Volume 21 (2010) Volume 20 (2009) Volume 19 (2008) Volume 18 (2007) Volume 17 (2006) Volume 16 (2005) Volume 15 (2004) Volume 14 (2003) Volume 13 (2002) Volume 26,
South African Journal of Industrial Engineering 26 (2015)
While the contents of this edition has been fixed for nearly two months, the final editing process took time, linked to a very busy time at work. The role of editor is a part time position, working with volunteers as section editors, technical editors, and reviewers. Thus this sometimes needs to take a second priority to other pressing matters. It is therefore very satisfying when we manage to get the journal ready and published on schedule!
Microstructure and mechanical properties of direct metal laser sintered Ti-6Al-4V : featured article
C. Scheffer and
South African Journal of Industrial Engineering 26, pp 1 –10 (2015)
Direct metal laser sintering (DMLS) is a selective laser melting (SLM) manufacturing process that can produce near net shape parts from metallic powders. A range of materials are suitable for SLM; they include various metals such as titanium, steel, aluminium, and cobalt-chrome alloys. This paper forms part of a research drive that aims to evaluate the material performance of the SLM-manufactured metals. It presents DMLS-produced Ti-6Al-4V, a titanium alloy often used in biomedical and aerospace applications. This paper also studies the effect of several heat treatments on the microstructure and mechanical properties of Ti-6Al-4V processed by SLM. It reports the achievable mechanical properties of the alloy, including quasi-static, crack growth behaviour, density and porosity distribution, and post-processing using various heat-treatment conditions.
Direkte metaal-laser-sintering is &apos;n selektiewe lasersmeltvervaardigingsproses wat naby aan netto-vorm onderdele van metaalpoeiers kan produseer. Verskeie materiale is geskik vir lasersmeltvervaardiging, onder andere titaan, staal, aluminium en kobaltchroom legerings. Die doel van dié navorsing is om die materiaaleienskappe van lasersmeltvervaardigde onderdele te ondersoek. &apos;n Titaan legering (Ti-6Al-4V) wat dikwels biomediese en ruimte toepassings het, word voorgehou. Verder word die effek van verskeie hittebehandelings op die mikrostruktuur en meganiese eienskappe van die titaan legering, na dit lasersmeltvervaardiging ondergaan het, ondersoek. Die quasi-statiese kraakvoortplanting, digtheid- en poreusheidsverspreiding en die verwerking met verskeie hittebehandelingtoestande word bespreek.
P.J. Van Staden
South African Journal of Industrial Engineering 26, pp 11 –26 (2015)
J.L. Jooste and
South African Journal of Industrial Engineering 26, pp 27 –43 (2015)
South African Journal of Industrial Engineering 26, pp 44 –58 (2015)
The Global Forum on Maintenance and Asset Management (GFMAM) was formed in 2011 to bring together various experts, practitioners, academics, and other professionals who are active in the field of asset and maintenance management. The primary mission of GFMAM is to develop and promote knowledge, standards, and education for the maintenance and asset management professions. To fulfil this mission, GFMAM developed an &apos;Asset Management Landscape&apos; document, which defines 39 subjects on asset management, grouped into six main subject areas.
C. Van der Merwe,
A. Van Rensburg and
South African Journal of Industrial Engineering 26, pp 59 –74 (2015)
Impact of TQM practices on innovation performance among manufacturing companies in Malaysia
M.H. Abdul Aziz,
T.O. Kowang and
South African Journal of Industrial Engineering 26, pp 75 –85 (2015)
This study examines the impact of total quality management (TQM) practices on an organisation&apos;s innovation performance. Correlation coefficient and regression analysis is used to examine the relationship between TQM practices and innovation performance. This study&apos;s sample is drawn from the manufacturing organisations located in the district of Rawang in the state of Selangor, Malaysia. The empirical results of this study confirm that TQM has a positive impact on innovation performance across five measured practices: customer focus, leadership, process management, strategic planning, and people management. Furthermore, the three most influential TQM practices are identfied as people management, process management, and customer focus. Managers in the manufacturing sector can find this study useful, especially if they are aiming to improve their organisation&apos;s innovation performance with the help of quality management practices.
Die impak van algehele gehaltebeheer op &apos;n organisasie se innovasievertoning word ondersoek. Korrelasiekoëffisiënt- en regressie analise word gebruik om die verhouding tussen algehele gehaltebeheer en innovasievertoning te ondersoek. Die steekproef is uit vervaardigingsorganisasies in die Rawang streek van Selangor, Maleisië geneem. Die empiriese resultate dui daarop dat algehele gehaltebeheer &apos;n positiewe invloed op die innovasievertoning van vyf gemete praktyke het, naamlik kliëntefokus, leierskap, prosesbeheer, strategiese beplanning en menslikehulpbronbestuur. Verder word menslikehulpbronbestuur, prosesbeheer en kliëntefokus as die drie invloedrykste algehele gehaltebeheer praktyke identifiseer. Bestuurders in die vervaardigingsektor mag hierdie resultaat nuttig vind, veral as hulle mik om hul organisasie se innovasievertoning te verbeter met die hulp van gehaltebeheer praktyke.
South African Journal of Industrial Engineering 26, pp 86 –101 (2015)
Die bestuur van navorsing en ontwikkeling (N&O) in die dissipline van vervoerinfrastruktuur is kompleks as gevolg van die multidissiplinêre aard van die werk. Die literatuur dui aan dat liniêre N&O modelle wat van idee tot &apos;n gebruikersproduk vorder, nie toepasbaar is vir die bestuur van sulke multidissiplinêre projekte nie. Hierdie studie fokus op die bepaling van die sleutel eienskappe wat benodig word vir &apos;n stelsel-gebaseerde benadering tot die bestuur van N&O projekte. Die inligting en data is versamel deur literatuur studies, onderhoude, en &apos;n e-pos vraelys met respondente van 42 internasionale N&O programme. Die resultate toon aan dat daar &apos;n behoefte is aan &apos;n stelsel-benadering tot die bestuur van N&O. Die studie het twaalf kernbeginsels gedefinieer vir so &apos;n stelsel-gebaseerde N&O proses.
S.O. Gilani and
South African Journal of Industrial Engineering 26, pp 102 –119 (2015)
M.H. Imam and
South African Journal of Industrial Engineering 26, pp 120 –134 (2015)
O.O. Asekun and
South African Journal of Industrial Engineering 26, pp 135 –149 (2015)
Rolling stock is the most maintenance intensive part of the railway system and therefore, the most vulnerable if maintenance is neglected. It is therefore, essential to have an efficient maintenance schedule for rolling stock components. A decision support model can be used to achieve this. However, selecting the appropriate model to achieve this is vital to the success of the decision support model. In this paper a practical way of selecting the appropriate model to develop a decision support for scheduling of rolling stock maintenance, is presented. A case study is used as a numerical example for the proposed framework.
Die rollende voorraad van &apos;n spoorwegstelsel vereis gewoonlik intensiewe instandhouding en daarom is dit die meeste kwesbaar indien instandhouding afgeskeep word. Dit is dus noodsaaklik dat &apos;n doeltreffende instandhoudingskedule vir rollende voorraad onderdele gebruik word. Om dit moontlik te maak, kan &apos;n besluitsteunmodel gebruik word. Om &apos;n suksesvolle besluitsteunmodel daar te stel, is dit egter noodsaaklik om die mees geskikte model hiervoor te kies. In hierdie artikel word &apos;n praktiese metode voorgestel om die mees geskikte model te kies vir die ontwikkeling van &apos;n skedulering besluitsteunmodel.
S. Grobbelaar and
South African Journal of Industrial Engineering 26, pp 150 –162 (2015)
Asset and maintenance managers are often confronted with difficult decisions related to asset replacement or repair. Various analytical models, such as decision analysis and simulation, can assist a manager in making better decisions. This paper proposes that by combining renewal theory with decision analysis methods, the expected value (EV) of information for non-repairable components can be calculated. Subsequently, it is proposed that this method can be used to determine the expected replacement cost per unit time of predictive maintenance. It is argued that this predicted cost will give the maintenance decision-maker the ability to compare it to the cost of alternative maintenance strategies when choosing between strategies. Although this paper is limited to non-repairable components, the theory and methodology can also be applied to repairable systems.
Bate- en instandhoudingsbestuurders word dikwels gekonfronteer met moeilike besluite rakende die vervanging of herstel van fisiese bates. Verskeie analitiese modelle, soos besluitsanalise en simulasie, kan die bestuurder help om beter besluite te neem. Hierdie artikel stel voor dat deur hernubare teorieë te kombineer met besluitnemingsmetodes, die verwagte waarde van inligting vir nie-herstelbare komponente bereken kan word. Gevolglik word dit voorgestel dat hierdie metode gebruik kan word om die verwagte koste per tyd eenheid van voorspelbare instandhouding te bereken. Daar word geargumenteer dat hierdie beraamde koste die instandhoudings-besluitnemer die vermoë sal gee om die koste van verskeie instandhoudingstrategieë te vergelyk wanneer daar gekies word tussen strategieë. Hierdie artikel sal beperk word tot nie-herstelbare komponente, maar deur soortgelyke prosesse te volg, kan die teorie uitgebrei word na herstelbare stelsels.
W. Krause and
South African Journal of Industrial Engineering 26, pp 163 –178 (2015)
M. Madou and
South African Journal of Industrial Engineering 26, pp 179 –190 (2015)
&apos;n Sentrifugale mikrofluidiese platform - &apos;n eerste in Suid-Afrika - vir die ontwikkeling van verskeie mikrofluidiese funksies word aangebied. Vinnige en lae-koste prototipering van sentrifugale mikrofluidiese skyfstrukture, asook &apos;n opstelling vir die toets van die strukture met sentrifugale kragte, word beskryf. Voorlopige resultate toon dat verskeie mikrofluidiese funksies soos vloeiklepping, vervoer, en druppelgenerasie haalbaar is. Hierdie werk bied &apos;n volledige sentrifugale mikrofluidiese platform, sowel as die boublokke waarop &apos;n verskeidenheid van mikrofluidiese toepassings en potensiële produkte vinnig en teen lae koste ontwikkel kan word.
E. Ras and
South African Journal of Industrial Engineering 26, pp 191 –206 (2015)
Suid-Afrika beskik oor &apos;n verskeidenheid minerale hulpbronne, en verskeie veredelings-aanlegte vir minerale is tans in die bedryf. Hierdie aanlegte moet effektief bedryf word sodat eindgebruikers van die produkte internasionaal kompeterend kan bly. &apos;n Volhoubare kontinue verbeteringsprogram is nodig om hierdie doelwitte te bereik. Verskeie raamwerke en modelle vir kontinue verbetering word in veredelingsaanlegte wêreldwyd gebruik, maar met wisselende sukses. Geen van hierdie modelle is spesifiek ontwikkel vir kontinue verbetering by veredelingsaanlegte nie. Die doel van hierdie studie was om belangrike faktore te bepaal vir &apos;n model vir kontinue verbetering by veredelingsaanlegte. &apos;n Opname het getoon dat &apos;n model wat verskeie elemente van bestaande modelle gebruik verkies word deur rolspelers in die industrie.
J. Padayachee and
South African Journal of Industrial Engineering 26, pp 207 –223 (2015)
The reconfigurable manufacturing system (RMS) paradigm was introduced in response to the need for a manufacturing environment that can handle high-frequency market-driven change. Although this has resulted in much research into the implementation of such a system, there is currently a gap in the technology covering the rapid establishment of control after a reconfiguration. This gap involves the detection of the factory floor&apos;s state, and the communication link between the factory floor and the high-level software (ERP and MES). This paper proposes a thin, hardware-supported middleware management system to support the reconfiguration process and to support industrial implementation to the RMS paradigm.
Die herkonfigureerbare vervaardigingstelsel paradigma is ontwikkel in reaksie op die behoefte aan &apos;n vervaardigingsomgewing wat hoë frekwensie, markgedrewe verandering kan hanteer. Alhoewel baie navorsing tot die implementering van so &apos;n stelsel gedoen is, bestaan daar steeds &apos;n gaping in die tegnologie tot die spoedige beheername van só &apos;n stelsel na &apos;n herkonfigurasie. Hierdie gaping behels die bepaling van die aanlegvloer se toestand en die kommunikasie tussen die aanlegvloer en die hoëvlak sagteware (soos ondernemingshulpbronbeplanning). &apos;n Dun, hardeware ondersteunde oorbruggingsbestuursagteware om die herkonfigurasie proses te steun en om die industriële implementering van herkonfigureerbare vervaardigingstelsels te bevorder, word voorgestel.
A.Y. Bin Ali and
South African Journal of Industrial Engineering 26, pp 224 –234 (2015)
Production throughput measures the performance and behaviour of a production system. Production throughput modelling is complex because of uncertainties in the production line. This study examined the potential application of the adaptive neuro-fuzzy inference system (ANFIS) to modelling the throughput of production under five significant production uncertainties: scrap, setup time, break time, demand, and lead time of manufacturing. The effects of these uncertainties on the production of floor tiles were studied by performing 104 observations on the production uncertainties over 104 weeks, based on a weekly production plan in a tile manufacturing industry. The results of the ANFIS model were compared with the multiple linear regression (MLR) model. The results showed that the ANFIS model was capable of forecasting production throughput under uncertainty with higher accuracy than was the MLR model, indicated by an R-squared of 98 per cent.
Produksie deurset meet die vertoning en gedrag van &apos;n produksiesisteem. Produksie deurset modellering is ingewikkeld as gevolg van die onsekerhede in die produksielyn. Hierdie studie ondersoek die toepassing van die aanpasbare neuro-wasige afleidingsisteem om die deurset van produksie onderhewe aan vyf noemenswaardige produksie onsekerhede, naamlik skroot, opstel tyd, breek tyd, aanvraag en die vervaardiging leityd. Die effek van hierdie onsekerhede op die vervaardiging van vloerteëls is ondersoek deur 104 weeklikse observasies op die produksie onsekerhede oor &apos;n tydperk van 104 weke te neem. Die resultate van die model is vergelyk met &apos;n meervoudige lineêre regressie model. Die resultate toon dat die aanpasbare neuro-wasige afleidingsisteem in staat was om produksie deurset onderhewe aan onsekerheid te voorspel met &apos;n hoër akkuraatheid as die meervoudige lineêre regressie model. Dit word aangedui met &apos;n bepaalheidskoëffisient van 98 persent.
J. Matthews and
South African Journal of Industrial Engineering 26, pp 235 –251 (2015)
&apos;n Stelsel vir die samestelling van bestellings wat uit &apos;n aantal parallelle, eenrigting uitsoeklyne bestaan, word ondersoek. Voorraadeenhede wat in distribusies gegroepeer word, word op &apos;n daaglikse basis in opmaaklyne toegewys. &apos;n Wiskundige programmeringsformulering en verslappings daarvan word aangebied. &apos;n Gulsige invoegings- en &apos;n gefaseerde gulsige invoegingsheuristiek word voorgestel om die probleem in &apos;n prakties uitvoerbare tyd op te los vir alle toetsgevalle. Die stapafstand van die werkers wat bestellings opmaak kon met ongeveer 22 persent verbeter word in vergelyking met die huidige benadering, maar daar was &apos;n toename in produkhantering en operasionele risiko.
Determining the suitability of a business process modelling technique for a particular application : case study
R.W. Geyer and
South African Journal of Industrial Engineering 26, pp 252 –266 (2015)
Organisations formally define and document their business processes in order to understand them and, subsequently, to enable continuous development, improvement, and management. Organisations can use business process modelling (BPM), which represents the design of graphical models that portray their business processes, to define and document their business processes formally. It is difficult, however, to select a suitable BPM technique in support of a specific application of BPM, owing to the considerable number of existing BPM techniques, the impact of their varying capabilities, and the lack of available formal measures to support evaluations of their suitability for specific modelling applications. This article presents a measurement framework to evaluate the usefulness of BPM techniques in specific modelling applications. It also presents the use of this measurement framework to determine an applicable BPM technique that can be applied in a specific modelling case.
Organisasies definieer en dokumenteer hulle besigheidsprosesse op &apos;n formele wyse om hulle prosesse te verstaan en gevolglik hulle deurlopende ontwikkeling, verbetering en bestuur te bemagtig. Ten einde die uitvoering van hierdie aktiwiteit aan te spreek, kan organisasies besigheidsprosesmodellering gebruik om grafiese modelle van hulle besigheidsprosesse te ontwerp. Daar word egter kennis geneem dat dit moeilik is om &apos;n geskikte besigheidsprosesmodellering tegniek te kies ter ondersteuning van &apos;n spesifieke toepassing van besigheidsprosesmodellering. Dit is weens die groot hoeveelheid bestaande besigheidsprosesmodellering tegnieke, die impak van hulle verskillende vermoëns, asook die gebrek aan formele maatstawwe om toe te pas om hulle bruikbaarheid vir sekere modellering aanwendings te bepaal. Die artikel stel verder maatstawwe voor vir evaluering van die bruikbaarheid van besigheidsproses modellering tegnieke vir sekere modellering aanwendings. Dit wys ook die gebruik van hierdie metings raamwerk om &apos;n geskikte besigheidsproses modellering tegniek vir &apos;n spesifieke modellering toepassing te bepaal.
A stochastic analysis approach on the cost-time profile for selecting the best future state map : case study
S.M. Seyedhosseini and
South African Journal of Industrial Engineering 26, pp 267 –291 (2015)
In the literature on value stream mapping (VSM), the only basis for choosing the best future state map (FSM) among the proposed alternatives is the time factor. As a result, the FSM is selected as the best option because it has the least amount of total production lead time (TPLT). In this paper, the cost factor is considered in the FSM selection process, in addition to the time factor. Thus, for each of the proposed FSMs, the cost-time profile (CTP) is used. Two factors that are of particular importance for the customer and the manufacturer - the TPLT and the direct cost of the product - are reviewed and analysed by calculating the sub-area of the CTP curve, called the cost-time investment (CTI). In addition, variability in the generated data has been studied in each of the CTPs in order to choose the best FSM more precisely and accurately. Based on a proposed step-by-step stochastic analysis method, and also by using non-parametric Kernel estimation methods for estimating the probability density function of CTIs, the process of choosing the best FSM has been carried out, based not only on the minimum expected CTI, but also on the minimum expected variability amount in CTIs among proposed alternatives. By implementing this method during the process of choosing the best FSM, the manufacturing organisations will consider both the cost factor and the variability in the generated data, in addition to the time factor. Accordingly, the decision-making process proceeds more easily and logically than do traditional methods. Finally, to describe the effectiveness and applicability of the proposed method in this paper, it is applied to a case study on an industrial parts manufacturing company in Iran.
Volgens die literatuur oor waarde stroom kartering (VSM) is die tydfaktor die enigste rede vir die kies van die beste eienskap toestand kaart (FSM) bo die ander voorgestelde alternatiewe. FSM word gekies as die beste opsie omdat dit die kortste totale produksie lei tyd het. Hierdie artikel oorweeg die kostefaktor in die FSM seleksie proses saam met die tydfaktor. Dus, vir elkeen van die voorgestelde FSM kaarte word die koste-tyd profiel gebruik. Twee faktore wat van uiterste belang vir die kliënt en vervaardiger is, naamlik die totale produk lei tyd en die direkte koste van die produk, is hersien en analiseer deur die area onder die koste-tyd profiel kurwe te bereken. Hierdie area staan bekend as die koste-tyd belegging. Verder word veranderlikheid in die gegenereerde data bestudeer in elk van die koste-tyd profiele, sodat die beste FSM meer presies gekies kan word. Die beste FSM is bepaal deur &apos;n voorgestelde treë-vir-treë stogastiese analise metode en &apos;n nie-parametriese Kernel skatting van die waarskynlikheiddigtheidfunksie van die koste-tyd belegging. Die seleksie van die beste FSM is dus nie net op die minimum verwagte koste-tyd belegging gekies nie, maar ook op die minimum verwagte veranderlikheid van die koste-tyd belegging. Deur hierdie metode van FSM seleksie sal fabrikante beide die koste faktor en die veranderlikheid in die gegenereerde data, en die tyd faktor in ag neem. Dienooreenkomstig sal die besluitnemingsproses gladder en meer logies verloop as tradisionele metodes. Laastens, om die doeltreffendeheid en toepasbaarheid van dié voorgestelde metode te ondersoek, word dit toegepas op &apos;n gevallestudie van &apos;n industriële onderdele fabrikant in Iran.