Scielo RSS <![CDATA[South African Journal of Industrial Engineering]]> http://www.scielo.org.za/rss.php?pid=2224-789020160002&lang=pt vol. 27 num. 2 lang. pt <![CDATA[SciELO Logo]]> http://www.scielo.org.za/img/en/fbpelogp.gif http://www.scielo.org.za <![CDATA[<b>Note from the editor</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2224-78902016000200001&lng=pt&nrm=iso&tlng=pt <![CDATA[<b>Using expanded real options analysis to evaluate capacity expansion decisions under uncertainty in the construction material industry</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2224-78902016000200002&lng=pt&nrm=iso&tlng=pt Capacity expansion generally requires large capital expenditure on illiquid assets. Therefore, decisions to enlarge capacity must support the organisation's strategic objectives and provide valuable input for the budgeting process. This paper applies an expanded form of Real Options Analysis (ROA) to generate and evaluate capacity expansion strategies under uncertainty in the construction material industry. ROA is applied to different expansion strategies associated with different demand scenarios. Evaluating a wider variety of strategies can reduce risk and sponsor decisions that maximise the firm's value. The case study shows that the execution of a lead expansion strategy with 10-year intervals under a 50 per cent demand satisfaction scenario produces superior results.<hr/>Die uitbreiding van kapasiteit vereis gewoonlik groot kapitaalbesteding op nie-likiede bates. Besluite om kapasiteit te vergroot moet dus die organisasie se strategiese doelstellings ondersteun en waardevolle insette tot die begrotingsproses lewer. Hierdie artikel pas 'n uitgebreide vorm van ware keuse analise toe om die kapasiteit uitbreidingstrategieë te genereer en te evalueer. Hierdie strategieë is vermoeid met onsekerheid in die boumateriaal industrie. Ware opsies analise (Real Options Analysis) is toegepas op verskillende uitbreidingstrategieë wat met verskillende vraagscenario's verband hou. Deur 'n groter verskeidenheid van strategieë te evalueer kan risiko verminder en besluite lewer wat 'n firma se waarde maksimeer. Die gevallestudie toon dat die uitvoer van 'n uitbreidingstrategie met tien jaar intervalle onderhewig aan 'n 50 per sent vraagbevrediging scenario die beste resultate lewer. <![CDATA[<b>Assessing the impact of new technology on complex sociotechnical systems</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2224-78902016000200003&lng=pt&nrm=iso&tlng=pt In complex sociotechnical systems, cognitive and social humans use technology to make sense of situations when making decisions. These elements make sociotechnical systems difficult to develop. A modelling and assessment methodology for systems engineering is required to understand the sociotechnical system's behaviour and underlying structure. Modelling captures the dynamic interaction, as well as the effect of humans in a complex environment. Cognitive Work Analysis and System Dynamics are two complementary approaches applied in mutual support within this context. The objective of this paper is to demonstrate a modelling methodology for complex sociotechnical systems, in order to support the systems engineering process.<hr/>In komplekse sosio-tegniese stelsels, gebruik kognitiewe en sosiale mense tegnologie om situasies te verstaan en besluite te neem. Hierdie elemente maak sosio-tegniese stelsels moeilik om te ontwikkel. 'n Modellering en assessering metodologie vir stelselingenieurswese is nodig om die gedrag van die sosio-tegniese stelsel en onderliggende struktuur te verstaan. Modellering implementeer die dinamiese interaksie sowel as die effek van die mens in 'n komplekse omgewing. Kognitiewe werkanalise en Stelsel-dinamika is twee aanvullende benaderings wat binne hierdie konteks toegepas is in wedersydse ondersteuning. Hierdie artikel demonstreer 'n modellering metodologie vir komplekse sosio-tegniese stelsels om die stelselsingenieurswese proses te ondersteun. <![CDATA[<b>A round robin study for laser beam melting in a metal powder bed</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2224-78902016000200004&lng=pt&nrm=iso&tlng=pt With its ability to fabricate fully dense three-dimensional structures by selectively melting micro-sized metal powder, the additive manufacturing process of laser beam melting (LBM) is considered by many to be a significant technology that is complementary to the conventional forming and subtractive manufacturing processes. However, even with its ability to fabricate structures with characteristics comparable to conventional fabrication, the LBM process often lacks the consistency and degree of repeatability essential for its industrial acceptance for certain end-product applications. Inconsistency in the characteristics of structures is often related to a combination of variations in system technology, process, and user influence. In order to understand fully the potential and limitations of the LBM process, the paper discusses the design, methodology, and results of a round robin test conducted within the Collaborative Working Group (CWG) lasers in production at the International Academy of Production Engineering (CIRP). Observed mechanical characteristics for samples from each of the participants are presented. The experiments are designed to obtain data related to mechanical characteristics for different build orientations and processing conditions in addition to the inherent system technology variations. The paper further discusses the observed process phenomena and their association with the induced mechanical characteristics.<hr/>Die additiewe laserstraal smeltproses word deur kenners as 'n noemenswaardige tegnologie wat bydra tot die konvensionele vorming- en masjineringvervaardigingsprosesse geag, omdat dit oor die vermoë beskik om digte, driedimensionele strukture te vervaardig. Selfs met dié vermoë om strukture met eienskappe soortgelyk aan die konvensioneel vervaardigde strukture, ly die laserstraal smeltproses dikwels aan n tekort aan konsekwentheid en herhaalbaarheid wat krities is tot die industriële aanvaarding daarvan. Die veranderlikheid in die eienskappe van strukture is dikwels verwant aan 'n kombinasie van variasies in die sisteem tegnologie, proses- en gebruikerinvloed. Hierdie navorsing bespreek n rondomtalie toets wat op verskeie laserstraal smelters, wat by die Internasionale Akademie van Produksieingenieurs (CIRP) in gebruik is, uitgevoer is. Die toetse se mikpunt was om die potensiaal en beperkinge geassosieer met die laserstraal smeltproses beter te verstaan. Die waargeneemde meganiese eienskappe van monsters van elkeen van die monsters word voorgehou. Die eksperimente is ontwerp om data, wat verwant is aan die meganiese eienskappe wanneer verskeie veranderlikes tydens die vervaardigingsproses teenwoordig is, te verkry. Die waargeneemde prosesverskynsels en hul assosiasies met die geïnduseerde meganiese eienskappe, word dan bespreek. <![CDATA[<b>Scheduling sequence-dependent colour printing jobs</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2224-78902016000200005&lng=pt&nrm=iso&tlng=pt A scheduling problem in the colour printing industry is considered in this paper. The problem is to find an optimal assignment of print jobs to each of a set of colour printers, as well as an optimal processing sequence for the set of jobs assigned to each printer. The objective is to minimise the makespan of the schedule to achieve a suitable balance between the workloads of the printers and the efficiencies of the job sequences assigned to the printers. A novel aspect of the problem is the way in which the printer set-up times associated with the jobs are job sequence-dependent - it is possible to exploit commonalities between the colours required for successive jobs on each machine. We solve this problem approximately by using a simple heuristic and three well-known metaheuristics. Besides colour printing, the scheduling problem considered here admits many other applications. Some of these alternative applications are also briefly described.<hr/>'n Skeduleringsprobleem uit die kleurdrukwerkbedryf word in hierdie artikel oorweeg. Die probleem vra vir 'n optimale toewysing van take aan elk van 'n versameling kleurdrukkers, sowel as die spesifikasie van 'n optimale volgorde waarin die take wat aan elke drukker toegewys is, uitgevoer moet word. Die doel is om die prosestyd van die drukker wat laaste klaarmaak te minimeer om sodoende 'n aanvaarbare balans tussen die werkladings van die drukkers en die taakvolgorde vir elke drukker te bewerkstellig. 'n Nuwe aspek van die probleem is die manier waarop die opsteltye van die drukkers vir die take volgorde-afhanklik is - dit is moontlik om gemeenskaplikhede tussen die kleure wat vir opeenvolgende take op elke masjien benodig word, uit te buit. Ons los hierdie probleem benaderd op deur gebruik te maak van 'n eenvoudige heuristiek asook drie bekende metaheuristieke. Behalwe vir kleurdrukwerk, het die skeduleringsprobleem wat hier beskou word vele ander toepassings. Sommige van hierdie toepassings word ook kortliks beskryf. <![CDATA[<b>Exploring the use of computer-mediated video communication in engineering projects in South Africa</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2224-78902016000200006&lng=pt&nrm=iso&tlng=pt Globally-expanding organisations that are trying to capitalise on distributed skills are increasingly using virtual project teams to shorten product development time and increase quality. These virtual teams, which are distributed across countries, cultures, and time zones, are required to use faster and better ways of interacting. Past research has shown that virtual teams that use computer-mediated communication (CMC) instead of face-to-face communication are less cohesive because they struggle with mistrust, controlling behaviour, and communication breakdowns. This study aims to determine whether project practitioners in South Africa perceive virtual teams that use videoconferencing as suffering from the same CMC disadvantages described in past research in other environments; and if they do, what the possible causes could be. This paper reports on a survey of 106 project practitioners in South Africa. The results show that these project practitioners prefer face-to-face communication over CMC, and perceive virtual teams using videoconferencing to be less cohesive and to suffer from mistrust and communication breakdowns, but not from increased conflict and power struggles. The perceived shortcomings of videoconferencing might result from virtual teams that use this medium having less time to build interpersonal relationships.<hr/>Organisasies maak toenemend gebruik van virtuele projekspanne wat verspreid is oor lande, kulture en tydsones en verbeterde maniere van interaksie benodig. Vorige navorsing het egter getoon dat virtuele spanne wat gebruik maak van rekenaar-bemiddelde kommunikasie (CMC) i.p.v. aangesig-tot-aangesig kommunikasie minder samehorig is omdat hulle sukkel met wantroue, beherende gedrag en gebrek aan kommunikasie. Hierdie studie ondersoek of 106 Suid-Afrikaanse projekpraktisyns van spanne wat videokonferensies gebruik ook meen dat die spanne ly aan die nadele van CMC wat in ander omgewings ondersoek is. Die resultate toon dat die respondente aangesig-tot-aangesig kommunikasie bo CMC verkies. Dit toon ook dat virtuele spanne wat gebruikmaak van videokonferensies minder samehorig is en ly aan wantroue en gebrek aan kommunikasie, maar nie aan verhoogde konflik en magstryd nie. <![CDATA[<b>Broadening the influence of asset managers through the six principles of persuasion</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2224-78902016000200007&lng=pt&nrm=iso&tlng=pt Asset managers (AMRs) have long struggled to influence others within their organisations to support Asset Management (AM) practices. This dilemma was further highlighted with the issuance of the AM suite of standards, ISO 55000. This paper explores an alternative approach to existing influence and change management approaches. Social psychology, and more specifically Robert Cialdini's 'six principles of persuasion', have benefited advertisers, lawyers, and even waiters in their respective professions, by helping them to influence others and induce compliance. Fortunately, AMRs can now do the same. Implementing these principles offers numerous advantages and requires small, practical, and often costless changes that can make a large difference to their ability to influence and persuade others in an ethical way.<hr/>Batebestuurders (BBs) sukkel reeds lank om ander mense binne hulle organisasies te beïnvloed om batebestuurspraktyke te ondersteun. Hierdie dilemma is verder beklemtoon met die uitreiking van die versamelde Batebestuur (BB) standaarde, ISO 55000. Hierdie studie ondersoek 'n alternatiewe benadering tot bestaande invloed- en veranderingsbestuursbenaderings. Sosiale sielkunde, en meer spesifiek Robert Cialdini se ses beginsels van oorreding, het al adverteerders, prokureurs en selfs kelners in hulle onderskeie beroepe bevoordeel. Dit het hulle gehelp om ander mense te beïnvloed en toegeeflikheid te verseker. Gelukkig kan BBs nou die selfde doen. Die implementering van hierdie beginsels bied verskeie voordele en vereis slegs klein, praktiese en meestal kostelose veranderinge wat kan lei tot groot verskille in hulle vermoë om ander mense op 'n etiese manier te beïnvloed en te oorreed. <![CDATA[<b>A strategy to tailor performance interventions based on the nature of organisational maturity of south manufacturing firms</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2224-78902016000200008&lng=pt&nrm=iso&tlng=pt The South African automotive component manufacturing sector is facing global pressure to remain competitive. Performance improvement interventions are often deployed in manufacturing companies that are aimed at improving competitiveness. The high failure rate of these performance improvement interventions should be considered when developing a programme strategy for implementation. Consideration should be given to the organisation's maturity and current performance when deciding which performance improvement intervention to select. The research objective was to establish the role of the organisational maturity variables in tailoring an integrated performance improvement intervention that develops organisational maturity and performance.<hr/>Die Suid-Afrikaanse motor komponent vervaardigingsektor staar huidiglik wêreldwye druk in die gesig om mededingend te bly. Prestasieverbeterings ingrypings word dikwels ontplooi in vervaardigingsmaatskappye met die doel om mededingendheid te verbeter. Die baie mislukkings van hierdie verbeterings ingrypings behoort in ag geneem te word wanneer dit kom by die ontwikkeling van die program strategie vir implementering. Oorweging moet gegee word aan maatskappye se volwassenheid en huidige prestasie wanneer daar oorweeg word watter prestasie verbetering ingryping geselekteer moet word. Hierdie navorsing se doelwit was om die rol van die maatskappy se volwassenheid veranderlikes vas te stel met betrekking tot die geintegreerde prestasie verbeterings ingryping wat organisatoriese volwassenheid en prestasie ontwikkel. <![CDATA[<b>Towards a framework for systemic creativity in engineering organisations</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2224-78902016000200009&lng=pt&nrm=iso&tlng=pt This article builds on earlier research that made the case for developing a framework to ensure increased, sustained, creative activity in engineering organisations. A milestone in the development of such a framework is the identification of the elements of creativity that need to be considered. This research reviews the literature on the systems perspective on creativity to identify seven elements of creativity that have been proposed in the literature. A literature review on each of these seven elements is presented to (i) determine whether the element should be included in the framework; (ii) define the element for the purpose of the framework; and (iii) determine whether any author proposes an aspect of creativity that cannot be accommodated under one of the seven elements as they have been defined here.<hr/>Hierdie artikel volg op vroeër navorsing wat 'n saak gemaak het vir die ontwikkeling van 'n raamwerk om verhoogde, volgehoue, kreatiewe aktiwiteit in ingenieursorganisasies te verseker. 'n Mylpaal in die ontwikkeling van so 'n raamwerk is die identifisering van die elemente van kreatiwiteit wat in ag geneem moet word. Hierdie navorsing hersien die literatuur oor die stelselperspektief op kreatiwiteit om sewe elemente van kreatiwiteit wat in die literatuur voorgestel word te identifiseer. 'n Literatuuroorsig van elkeen van hierdie sewe elemente word aangebied om (i) te bepaal of die element in die raamwerk ingesluit moet word; (ii) die element te definieer vir die doel van die raamwerk; en (iii) vas te stel of enige outeur 'n aspek van kreatiwiteit voorstel wat nie onder een van die sewe elemente soos wat hul hier definieer is bygewerk kan word nie. <![CDATA[<b>Mathematical and simulation techniques for modelling urban train networks</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2224-78902016000200010&lng=pt&nrm=iso&tlng=pt Railway systems can pose complex problems for the scheduling and operation of trains. A passenger rail service's first priority is to provide a punctual and safe transport service to its customers. But doing so is a major challenge for rail network operators, as disruptions are inevitable, especially in densely-populated networks. Disruptions can be caused not only by infrastructure or rolling stock breakdowns, but also by maintenance activities, new rolling stock, or new train services. Managing these disruptions and predicting the extent of its effects is a crucial part of rail network operation. Mathematical models and simulation can be applied to these problems. This paper will review the literature concerning the modelling of train networks.<hr/>Spoorwegstelsels skep soms komplekse probleme met betrekking tot die skedulering en die bedryf van treine. 'n Passasiers-spoordiens se eerste prioriteit is om stiptelike en veilige vervoer te verskaf aan sy gebruikers. Om 'n stiptelike en betroubare diens te lewer is 'n groot uitdaging vir netwerk operateurs, aangesien trein dienste maklik ontwrig word in digbevolkte netwerke. Ontwrigtinge word nie net deur infrastruktuur en rollende materiaal falings veroorsaak nie, maar ook deur infrastruktuur onderhoud, nuwe rollende materiaal, en nuwe treindienste wat ingestel kan word. Die bestuur van dié ontwrigtinge en die akkurate vooruitskatting van die effek op die res van die netwerk is 'n kritiese komponent van die bedryf van 'n trein netwerk. Wiskundige modelle en simulasie metodes kan toegepas word op dié tipe probleme. Hierdie artikel bespreek die literatuur wat oor die modellering van trein netwerke handel. <![CDATA[<b>Improving product development performance through knowledge outsourcing: a study of the automotive industry in Iran</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2224-78902016000200011&lng=pt&nrm=iso&tlng=pt This study aims to explore the dynamics of the knowledge supply process for new product development in the automotive industry, and to evaluate the impact of knowledge outsourcing on new product development performance. The model was developed using a literature review and a multiple case study approach that looked at ten research and development companies from the automotive industry in Iran. The results indicate that knowledge outsourcing would improve new product development performance by increasing the flexibility of the new product development process to react to the environment's volatility, with few penalties in time and costs for automotive product development.<hr/>Die dinamiek van die voorkennisverkrygingsproses vir die ontwikkeling van nuwe produkte in die motorvoertuigindustrie word ondersoek om sodoende die impak van die uitkontraktering van die voorkennisverkryginsproses op die nuwe produkontwikkelingsproses te bepaal. Die voorgestelde model is ontwikkel deur 'n literatuurstudie en deur van veelvoudige gevallestudies van motorvervaardigers in Iran gebruik te maak. Die resultate toon dat die uitkontrak-tering van die voorkennisverkryginsproses die produkontwikkelings-proses sal verbeter deur die aanpasbaarheid van die produkontwik-kelingsproses by die mark se vlugtigheid te verhoog met weinige nadele, met betrekking tot die tyd en onkostes, wat van toepassing op die motor-voertuig produkontwikkelingsproses is. <![CDATA[<b>Exploiting deterministic maintenance opportunity windows created by conservative engineering design rules that result in free time locked into large high-speed coupled production lines with finite buffers</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2224-78902016000200012&lng=pt&nrm=iso&tlng=pt Conservative engineering design rules for large serial coupled production processes result in machines having locked-in free time (also called 'critical downtime' or 'maintenance opportunity windows'), which cause idle time if not used. Operators are not able to assess a large production process holistically, and so may not be aware that they form the current bottleneck - or that they have free time available due to interruptions elsewhere. A real-time method is developed to accurately calculate and display free time in location and magnitude, and efficiency improvements are demonstrated in large-scale production runs.<hr/>Konserwatiewe ingenieursontwerpreëls vir groot reeksgekoppelde produksieprosesse lei tot beskikbare vrye tyd (ook bekend as 'kritieke dooie tyd' of 'onderhoudsgeleenthede'), wat indien nie gebruik word nie, onbenutte tyd tot gevolg kan hê. Operateurs is nie in staat om 'n grootskaalse produksieproses op holistiese wyse te beoordeel nie, en mag gevolglik nie besef dat hulle op 'n bepaalde stadium óf die knelpunt is óf dat daar vrye tyd beskikbaar is as gevolg van onderbrekings elders nie. 'n Intydse metode is ontwikkel om vrye tyd akkuraat te bereken en te vertoon, beide wat posisie en grootte betref. Effektiwiteitsverbeterings word aangetoon in grootskaalse produksielopies. <![CDATA[<b>An empirical analysis of issues and trends in manufacturing productivity through a 30-year literature review</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2224-78902016000200013&lng=pt&nrm=iso&tlng=pt This paper analysed the keywords in manufacturing productivity-related studies over the last 30 years to consider the change in the concept of 'productivity', a longstanding and important factor in studies about manufacturing. After first identifying 110,269 keywords in related research through 11,237 academic papers, we narrowed them down to 97 in nine categories by applying certain criteria. Most of the previous studies dealt with productivity in the context of corporate data; but this study investigated the change in the concept of manufacturing productivity by analysing the keywords of many studies of this concept. We classified the 30 years from 1980 to 2009 into five eras of productivity, according to their representative characteristics, using the analysed keywords. We expect that this study will serve as a practical guideline for managers in industry, and as an academic foundation for future research into productivity.<hr/>Die sleutelwoorde in die navorsingstudies oor vervaardigings-produktiwiteit oor die afgelope dertig jaar is geanaliseer om die verandering in die definisie van produktiwiteit as konsep te verstaan. Nadat 110,269 sleutelwoorde in 11,237 navorsingsartikels geïdentifiseer is, is die sleutelwoorde verminder tot 97 wat in nege kategorieë gesorteer is. Dit is gedoen deur sekere kriteria toe te pas. Die meeste van die vorige studies het met produktiwiteit gehandel binne die konteks van korporatiewe data, maar hierdie studie ondersoek die verandering in die konsep van vervaardigingsproduktiwiteit deur die sleutelwoorde van studies oor hierdie konsep. Die tydperk van 1980 tot 2009 is in vyf eras van produktiwiteit geklassifiseer. Die verwagting is dat hierdie studies kan dien as 'n praktiese riglyn vir bestuurders in die industrie en as 'n akademiese grondslag vir toekomstige navorsing oor produktiwiteit. <![CDATA[<b>Optimisation of radio transmitter locations in mobile telecommunication networks</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2224-78902016000200014&lng=pt&nrm=iso&tlng=pt Multiple factors have to be taken into account when mobile telecommunication network providers make decisions about radio transmitter placement. Generally, area coverage and the average signal level provided are of prime importance in these decisions. These criteria give rise to a bi-objective problem of facility location, with the goal of achieving an acceptable trade-off between maximising the total area coverage and maximising the average signal level provided to the demand region by a network of radio transmitters. This paper establishes a mathematical modelling framework, based on these two placement criteria, for evaluating the effectiveness of a given set of radio transmitter locations. In the framework, coverage is measured according to the degree of obstruction of the so-called 'Fresnel zone' that is formed between handset and base station, while signal strength is modelled taking radio wave propagation loss into account. This framework is used to formulate a novel bi-objective facility location model that may form the basis for decision support aimed at identifying high-quality transmitter location trade-off solutions for mobile telecommunication network providers. But it may also find application in various other contexts (such as radar, watchtower, or surveillance camera placement optimisation).<hr/>Verskeie faktore moet in ag geneem word wanneer radiosender-plasingsbesluite deur mobiele telekommunikasienetwerke gemaak word. In die algemeen word area-oordekking en gemiddelde seinsterkte in hierdie besluite as belangrike kriteria geag. Hierdie kriteria gee aanleiding tot 'n twee-doelige fasiliteitplasingsprobleem gemik op die soeke na aanvaarbare afruilings tussen die maksimering van totale area-oordekking en die maksimering van gemiddelde seinsterkte aan gebiede waarin aanvraag na oordekking bestaan. 'n Wiskundige modelleringsraamwerk, gebaseer op hierdie twee plasingskriteria, word in hierdie artikel vir die evaluering van 'n versameling radiosenderliggings daargestel. In die raamwerk word oordekking gemeet volgens die mate waartoe die Fresnel-sone tussen die handtoestel en die basisstasie belemmer is, terwyl seinsterkte aan die hand van radiogolf-voortsettingsverliese gemodelleer word. Hierdie raamwerk word gebruik om 'n nuwe, twee-doelige fasiliteitplasingsmodel te formuleer wat as basis kan dien vir besluitsteun in die soeke na hoë-kwaliteit senderliggingsafruilings deur mobiele telekommunikasie-netwerkverskaffers, maar vind ook toepassing in verskeie ander kontekste (soos die optimale plasing van radars, uitkyktorings, of waarnemingskameras). <![CDATA[<b>A maintenance performance measurement framework that includes maintenance human factors: a case study from the electricity transmission industry</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2224-78902016000200015&lng=pt&nrm=iso&tlng=pt Over the past two to three decades, maintenance management has undergone a paradigm shift; it is no longer seen as a necessary evil, but as an integral part of the business process that creates value for the organisation. The next step in the evolution of maintenance management is a maintenance performance measurement that includes human factors. The human factors in maintenance are well-known in the aviation industry, as it gained momentum in the early 1990s after a series of serious aviation accidents. Other industries, however, have been slow to integrate the human factor in their maintenance performance measurements. This paper discusses the results of a research project that investigated the use and importance of maintenance management performance measurements that focus specifically on human factors as part of the overall performance management system. From the research presented in this paper, 'motivation' and 'competence' were identified as the most important human performance factors in the maintenance of electricity transmission systems.<hr/>Instandhoudingsbestuur het 'n paradigmaskuif ondergaan in die afgelope twee of drie dekades, vanaf 'n noodsaaklike euwel tot 'n integrale deel van die besigheidsproses wat waarde toegevoeg tot die organisasie. Die volgende groot ontwikkeling in instandhoudingsbestuur is prestasiemeting waarby meslike faktore ingesluit word. Menslike motiveringsfaktore is welbekend in die lugvaartindustrie sedert die vroeë 1990s na 'n rits ernstige lugvaartongelukke, maar ander industrieë was stadiger om menslike faktore in te sluit in prestasiemeting van instandhouding. Hierdie artikel bespreek die resultate van 'n navorsingsprojek wat die gebruik en belangrikheid van prestasiemetings vir instandhoudingsbestuur ondersoek het met spesifieke fokus op die menslike faktore as deel van die totale prestasiebestuurstelsel. Motivering en bevoegdheid is geïdentifiseer as die belangrikste menslike prestasiefaktore vir die instandhouding van elektriese verspreidingstelsels. <![CDATA[<b>A mathematical model using AHP priorities for soccer player selection: a case study</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2224-78902016000200016&lng=pt&nrm=iso&tlng=pt The process of player selection in multi-player sports like soccer is a complex multi-criteria problem. In this paper, a two-phase approach is proposed for soccer player selection. In the first phase, the attributes of each player - based on their position within a soccer team - is prioritised using the Analytic Hierarchic Process (AHP). In the second phase, a 0-1 integer linear programming model is developed using the weights of player attributes, and the top performers are determined for inclusion in the team. Finally, a case study on the Turkish soccer club called Fenerbahce is used to illustrate the applicability and performance of the proposed approach.<hr/>Die proses van speler-seleksie in spansporte soos sokker is 'n ingewikkelde, multikriteria probleem. 'n Twee-fase benadering om die kies van spelers vir 'n sokkerspan word voorgestel. In die eerste fase word die eienskappe van die speler prioritiseer deur 'n analitiese hiërargie proses. Die prioritisering is gebaseer op hulle posisie in die span. In die tweede fase word 'n binêre lineêre programmeringsmodel ontwikkel deur gewigte aan n speler se eienskappe toe te ken. Toppresteerders word so identifiseer en in die span ingesluit. Laastens word 'n gevallestudie op die Turkse klubspan Fenerbahce gebruik om die toepaslikheid en vertoning van die voorgestelde benadering te bepaal. <![CDATA[<b>Development of an automated guided vehicle controller using a model-based systems engineering approach</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2224-78902016000200017&lng=pt&nrm=iso&tlng=pt Automated guided vehicles (AGVs) are widely used for transporting materials in industry and commerce. In this research, an intelligent AGV-based material-handling system was developed using a modelbased systems engineering (MBSE) approach. The core of the AGV, the controller, was designed in the system modelling language environment using Visual Paradigm software, and then implemented in the hardware. As the result, the AGV's complex tasks of material handling, navigation, and communication were successfully accomplished and tested in the real industrial environment. The developed AGV is capable of towing trolleys with a weight of up to 200kg at walking speed. The AGV can be incorporated into an intelligent material-handling system with multiple autonomous vehicles and work stations, thus providing flexibility and reconfigurability for the whole manufacturing system. Ergonomic and safety aspects were also considered in the design of the AGV. A comprehensive safety system that is compliant with industrial standards was implemented.<hr/>Die nywerheid- en handelsbedryf gebruik dikwels outomatiese begeleide voertuie. 'n Outomatiese begeleide voertuig gebaseerde materiaalhanteringsisteem is ontwikkel deur 'n modelgebaseerde benadering. Die voertuig se beheerder is ontwikkel deur gebruik te maak van Visual Paradigm sagteware en is op die hardeware geïmplementeer. Die ingewikkelde materiaalhanteringstake wat na die voertuig gestuur is, wat onder meer die hantering, navigasie en kommunikasie insluit, is suksesvol uitgevoer en getoets in 'n werklike nywerheidsomgewing. Die onwikkelde outomatiese begeleide voertuig kan waentjies met 'n massa van 200kg teen stapspoed sleep. Die outomatiesbegeleide voertuig kan by 'n intelligente materiaalhanteringsisteem, wat uit verskeie outonome voertuie en werkstasies bestaan, geïntegreer word. Dit bied dus die vermoë om die hele vervaardigingstelsel te herkonfigureer of maklik aan te pas. Ergonomiese en veiligheidsaspekte is ook oorweeg vir die ontwerp van die voertuig. 'n Omvattende veiligheidstelsel wat aan die toepaslike industriestandaarde voldoen is geïmplementeer. <![CDATA[<b>Strategic production line synchronisation</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2224-78902016000200018&lng=pt&nrm=iso&tlng=pt A study was conducted at the sole global producer of suspension struts for a particular vehicle manufacturer. This supplier is currently able to meet customer demand. However, it does so because of a large finished goods and work-in-progress (WIP) inventory. The plant operates two production processes that are separated by a large buffer of WIP, which essentially decouples the production processes. This study aimed to reduce this WIP buffer; this would require the processes to become synchronised, bearing in mind that the reliability of delivery should not decrease. A tool that considers time, quality, and machine capacity was developed to assess the impact of line synchronisation on company performance figures. It was found that line synchronisation produced several benefits for the supplier, including batch size reduction, lower inventory levels, and associated shorter lead times. This further allowed the supplier to improve flow in the plant by introducing a pull system. Improved visual oversight could lead to further improved problem-solving and innovation.<hr/>'n Gevallestudie is by die alleenverskaffer van suspensiestutte vir 'n spesifieke motorvervaardiger geloods. Die vervaardiger kan tans die vraag van die kliënt bevredig, maar dit is as gevolg van 'n groot voorraad van voltooide goedere en werkstukke in proses. Die fabriek bedryf twee vervaardigingsprosesse wat met 'n groot buffer van werkstukke in proses geskei word. Dit ontkoppel effektief die produksieprosesse. Die doel van hierdie studie is om die werk-in-proses buffer te verminder. Dit vereis dat die prosesse gesinkroniseer moet word sonder dat die betroubaarheid verminder word. n Gereedskapstuk wat die tyd, gehalte en masjienkapasiteit in ag neem is ontwikkel om die impak van produksielyn sinkronisering op die maatskappy se vertoning te bepaal. Daar is gevind dat die produksielyn sinkronisering verskeie voordele vir die verskaffer inhou, onder andere vermindering van lotgrootte, laer voorraad-vlakke en korter leitye. Dit het die verskaffer toegelaat om die vloei in die fabriek te verbeter deur n trekstelsel bekend te stel. Verbeterde opsig kan lei tot verder verbeterde probleemoplossing en innovasie. <![CDATA[<b>A fuzzy expert system for the integration of collaborative supply chains</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2224-78902016000200019&lng=pt&nrm=iso&tlng=pt The integration of supply chains has become a global operations strategy for many organisations because it allows them to improve customer service, minimise operating costs, and synchronise channels across the supply chain. This paper presents the design and implementation of a fuzzy expert system for the integration of collaborative supply chains. A measurement instrument that was statistically validated and formulated using a mathematical model was designed to implement the fuzzy expert system. This instrument was applied in 44 small-, medium-, and large-sized Mexican enterprises to determine their integration level. Specific actions were proposed, based on the results, to improve the attained integration level.<hr/>Die integrasie van voorsieningskettings is deesdae 'n omvattende strategie vir baie organisasies, omdat dit hulle toelaat om kliëntediens te verbeter. Die ontwerp en implementering van 'n wasige ekspertstelsel word voorgehou. 'n Statisties gevalideerde meetinstrument wat met 'n wiskundige model geformuleer is, is ontwerp om die wasige ekspertstelsel te implementeer. Dié meetinstrument is in 44 klein, medium en groot Meksikaanse ondernemings toegepas om hulle integrasievlak te bepaal. Spesifieke aksies, gegrond op die resultate, is aanbeveel om die integrasievlak te verbeter.