Scielo RSS <![CDATA[South African Journal of Industrial Engineering]]> http://www.scielo.org.za/rss.php?pid=2224-789020140001&lang=es vol. 25 num. 1 lang. es <![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=S2224-78902014000100001&lng=es&nrm=iso&tlng=es <![CDATA[<b>Technology-conversant management education: Introducing a new discipline</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2224-78902014000100002&lng=es&nrm=iso&tlng=es In the first quarter of 2013, the Department of Industrial Engineering at the University of Stellenbosch launched a new academic course, Strategic Technology Analysis (STA), as an elective in its M.Sc. in Engineering Management and M.Eng. Industrial Engineering degrees. STA views technology as a knowledge area in its own right, focuses on the inherent characteristics of technology, and explores its natural order. The purpose was to ascertain whether a course of this nature, which offered the outline for a new academic discipline, would be of benefit to a technology-conversant management programme. The course was well-received. It encouraged a greater awareness of technological positioning - i.e., aligning overall corporate strategy with new opportunities across the entire technological frontier. This article describes the background to this initiative, the history of STA, its inherent structure, and its role in professional practice. It then looks ahead at the possible dissemination of this knowledge into different settings where technology-conversant management is taught.<hr/>In die eerste kwartaal van 2013 het die Departement Berdyfsingenieurswese aan die Universiteit van Stellenbosch 'n nuwe akademiese module geloods, te wete Strategiese Tegnologie Analise (STA). Dit is as keusevak in die graad in M.Sc. in Ingenieursbestuur en M.Ing. in Bedryfsingenieurswese, aangebied. STA, beskou tegnologie as 'n kennisgebied in eie reg, konsentreer op die inherente eienskappe van tegnologie, en verken die natuurlike orde daarvan. Die leierskap van die Department wou vasstel of die plasing van so 'n module, in 'n leerplan vir ingenieurs- en tegnologiebestuur, akademiese voordele inhou. Die module was goed ontvang. Dit het bygedra tot groter insae in tegnologiese posisionering - d.w.s. die afstemming van ondernemingstrategie op nuwe geleenthede in die spektrum van tegnologieë. Hierdie artikel beskryf die agtergrond vir die besluit, die geskiedenis van STA, die onderliggende struktuur van die vak, en die gebruik daarvan in professionele praktyk. Daarna verken die artikel die verspreiding van hierdie kennis in verskeie opleidingsomgewings wat onderrig verskaf in tegnologies-kundige bestuur. <![CDATA[<b>The organisational performance impact of ERP systems on selected companies</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2224-78902014000100003&lng=es&nrm=iso&tlng=es There is a need to determine the performance benefits that firms gain from enterprise resource planning (ERP) systems, and the factors that contribute to success. Consequently, the central research problem is: To determine the impact of ERP systems on organisational performance by analysing achieved ERP benefits within the framework of a suitable performance measurement system (PMS), and to investigate the association between critical success factors (CSFs) and ERP benefits. A list of expected ERP benefits and CSFs is compiled. Performance measurement models are evaluated, and one model is designed to evaluate ERP impact. ERP experts refine identified ERP benefits and CSFs using structured interviews. These are built into a questionnaire, and used to survey South African (SA) companies in manufacturing, mining, and power generation. Results indicate that business benefits are realised by companies that implement ERP systems. By building benefits into the performance measurement model, a positive impact on organisational performance is observed. Although a core list of CSFs is identified, and three associations are found between CSFs and ERP benefits, further research is needed.<hr/>Daar bestaan 'n behoefte om die voordeel wat onderneminghulpbronbeplanningstelsels aan ondernemings bied te bepaal en die faktore wat bydra tot die sukses daarvan te ondersoek. Die navorsingsvraag is dus: Om die impak van onderneminghulpbronbeplanningstelsels op die organisatoriese prestasie van ondernemings te ondersoek binne die raamwerk van 'n gepaste prestasiebestuurstelsel, asook die verband tussen kritiese suksesfaktore en onderneminghulpbronbeplanningstelsels. 'n Lys van verwagte ondermeninghulpbronbeplanning voordele en kritiese suksesfaktore is saamgestel. Prestasiemeetmodelle is evalueer en een model is ontwerp om onderminghulpbronbeplanning se impak te evalueer. Hieruit word 'n vraelys saamgestel. Die vraelys word dan gerig aan Suid-Afrikaanse ondernemings in die vervaardiging-, mynbou- en kragopwekkingbedryf. Die resultate toon dat besigheidsvoordele realiseer word deur ondernemings wat onderneminghulpbronbeplanningstelsels implementeer. 'n Positiewe impak op organisatoriese prestasie word ervaar deur voordele by die prestasiemeetmodel in te sluit. <![CDATA[<b>A decision support system for equipment allocation in a telemedicine referral network</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2224-78902014000100004&lng=es&nrm=iso&tlng=es Telemedicine applications have had much success in strengthening health systems worldwide. Unfortunately, many systems are implemented without decisions based on proper needs assessments. In South Africa, this 'technology push' approach has led to a large amount of equipment standing dormant. It is proposed that the potential of telemedicine be measured prior to implementation, thus 'pulling' the technology towards a clinical need. A decision support system is developed that uses health informatics and computational intelligence to determine the need for telemedicine and to allocate equipment in a network of facilities to achieve the best cost benefit. The system facilitates the collection and storage of electronic health record (EHR) data in a data warehouse. A linear programming model is used with a genetic algorithm. The system was developed and tested for the South African public health sector, using data from 27 hospitals in the Western Cape Province. Results have shown that if telemedicine workstations with specific peripheral equipment, as determined by the algorithm, were implemented in the given period, an estimated R8.7 million in referral costs could have been saved for the 27 hospitals. Thus the case study provided evidence for the benefits of implementation in the chosen network of hospitals. This new application of health informatics could provide telemedicine management with a useful tool for making implementation decisions based on evidence. Future work would include the development of similar systems for other markets.<hr/>'n Verskeidenheid telegeneeskunde toepassings het reeds groot sukses behaal in die bevordering van gesondheidsdienste wêreldwyd. Ongelukkig word tegnologie dikwels geimplementeer sonder om besluitneming te baseer op behoorlike behoefte bepalings. In Suid-Afrika, het hierdie 'tegnologie stoot' benadering gelei tot 'n groot hoeveelhede ongebruikte toerusting. Daar word voorgestel dat die potensiaal van telemedisyne gemeet moet word, voor implementering, om sodoende tegnologie te 'trek' na kliniese behoefte. 'n Besluitneming ondersteuning stelsel is ontwikkel wat gebruik maak van gesondheidsorg informatika en rekenkundige intelligensie, om die behoefte vir tele-geneeskunde te bepaal en daarvolgens toerusting toe te ken aan 'n netwerk van gesondheidsorg fasiliteite, om die beste kostevoordeel te bereik. Die stelsel fasiliteer die versamel en berg van elektroniese mediese rekord data in 'n data stoor. 'n Lineêre programmering model word gebruik met 'n genetiese algoritme opgelos. Die stelsel is ontwikkel en getoets vir die Suid-Afrikaanse openbare gesondheidsektor, met behulp van data van 27 hospitale in die Wes-Kaap Provinsie. Resultate toon dat indien telemedisyne werkstasies met spesifieke aanvullende toerusting, soos bepaal deur die algoritme, beskikbaar was in die gegewe tydperk, 'n beraamde R8.7 miljoen gespaar kon word met betrekking tot pasiënt verwysingkoste. Die gevallestudie toon dus van die voordele van implementering in die gekose netwerk van hospitale. Hierdie nuwe toepassing van gesondheidsorg informatika kan dien as 'n nuttige hulpmiddel vir tele-geneeskunde besluitnemers in tele-geneeskunde om besluite gebaseer op konkrete bewyse. Toekomstige werk sal die ontwikkeling van soortgelyke stelsels vir ander markte insluit. <![CDATA[<b>Microfocus X-ray computed tomography (CT) analysis of laser sintered parts</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2224-78902014000100005&lng=es&nrm=iso&tlng=es Microfocus X-ray computed tomography (CT) scanning is a three-dimensional (3D) non-destructive technique that is useful in many research and technology fields. Similar to two-dimensional (2D) X-ray inspections, this 3D technology allows the investigation of almost any material down to 1 micron spatial resolution and higher. In this paper we present a characterisation and demonstration of the use of CT to analyse the 3D volume of laser sintered parts including analyses of porosity, dimensional measurement of cracks and other features, and a demonstration of quality testing methods which can be used to quickly identify problems in production.<hr/>Mikrofokus X-straal rekenaar-tomografie (RT) is 'n drie-dimensionele (3D) nie-destruktiewe tegniek wat bruikbaar is in baie navorsing en tegnologie velde. Soortgelyk aan twee dimensionele (2D) X-straal inspeksies, laat hierdie 3D tegnologie dit toe om enige materiaal in 3D te ondersoek tot 1 mikron (en hoër) ruimtelike resolusie. In hierdie artikel word 'n karakterisering en demonstrasie van die gebruik van RT aangebied om die 3D volume van laser-gesinterde onderdele te analiseer, insluitend die analise van porositeit, dimensionele metings van krake en ander eienskappe en 'n demonstrasie van kwaliteit toets metodes wat gebruik kan word om vinnig probleme in produksie te identifiseer. <![CDATA[<b>Supporting business process design through a business fractal approach</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2224-78902014000100006&lng=es&nrm=iso&tlng=es The role and position of business process management in an organisation depends on the value it contributes to the organisation's sustainability. Business process design ensures that the conceptual business process strategy is translated into appropriate user requirements and functional requirements, and is ultimately implemented through some kind of enabling mechanism. In reality, business process design proves, at best, to be difficult when capturing and translating the complexity of business systems. In this paper, the concept of a business fractal is introduced to demonstrate an alternative way of doing business process design.<hr/>Die rol en posisie van besigheidsprosesbestuur hang af van die waardetoevoeging van besigheidsprosesbestuur tot die uitvoerbaarheid van die organisasie. Dit is in die belang van die ontwerp van die besigheidsproses dat die besigheidstrategie omskryf word in die gebruikersbehoeftestellings en funksionelestellings, en geïmplementeer word in die fisiese uitvoering van die besigheidsproses, hetsy deur 'n rekenaarstelsel of deur besigheidsprosedures. Dit is egter in realiteit baie moeilik om strategie af te wentel na implementeringsprosedures as gevolg van die kompleksiteit van besigheidsprosesse. In hierdie artikel word die konsep van 'n besigheidsfraktaal bekend gestel as 'n alternatiewe manier om besigheidsproses ontwerp te doen. <![CDATA[<b>Laser coating of zirconium and ZrO<sub>2</sub> composites on Ti<sub>6</sub>Al<sub>4</sub>V for biomedical applications</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2224-78902014000100007&lng=es&nrm=iso&tlng=es Coating is a technology for improving the surface properties of components. Laser coating produces uniform composition with thickened layers that display a good metallurgical bond to the base material. These coatings are dense and crack-free, and have non-porous microstructures. The advantages of the process are that the components' surface will have high resistance to wear and corrosion, even at elevated temperatures. In this work, Ti6Al4V base material was coated with zirconium and zirconia composite material to improve the base material's resistance to corrosion and wear. Zirconium powder mixed with binder (PVA and cold glue) was melted to produce a thin layer, which was then bonded to the Ti6Al4V by irradiation with a fibre laser, thus forming a zirconium + zirconia composite due to an in-situ reaction in the liquid state. The presence of binder in the Zr powder indicated a change in the microstructural behaviour, as the results showed a gradual increase in the hardness of the coated Ti6Al4V from top to bottom. It was also found that Zr + PVA binder coating was uniformly deposited, and had a less dendritic structure compared with Zr without binder or Zr with cold glue.<hr/>Oppervlakbedekking is 'n tegnologie wat die oppervlak-eienskappe van komponente verbeter. Laseroppervlakbedekking verskaf 'n uniforme samestelling van dik lae met goeie metallurgiese hegting aan die basis materiaal. Hierdie bedekkings is dig en kraakvry en het nie-poreuse mikrostrukture. Die voordele van die proses is dat die komponent se oppervlak 'n hoë weerstand teen slytasie en korrosie het, selfs by hoë temperature. Ti6Al4V basis materiaal word in dié studie bedek met Zr en ZrO2 samestellings om die komponent se weerstand teen korrosie en slytasie te verbeter. Zr-poeier wat gemeng is met 'n verbinder (PVA en koue lym) is gesmelt om 'n dun lagie te vorm. Die lagie is gebind aan die Ti6Al4V component deur bestraling met 'n vesellaser. Die teenwoordigheid van die verbinder in die Zr-poeier het gelei tot 'n verandering in die mikrostruktuur, die resultate toon 'n geleidelike toename in die hardheid van die bedekte Ti6Al4V van bo na onder. Daar is ook gevind dat die bedekking met die Zr saam met die PVA verbinder uniform gedeponeer is en 'n minder dendritiese struktuur gehad het as die Zr sonder binder of die Zr met die koue lym. <![CDATA[<b>A systems thinking approach to the sustainability of quality improvement programmes</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2224-78902014000100008&lng=es&nrm=iso&tlng=es The challenge for organisations to continually provide the best return on investment for their shareholders has become increasingly difficult through globalisation of the market place. There are many responses a company could make to these challenges - for example, new product development, increased market capitalisation, cost reduction initiatives, and quality management. This last response focuses on, but is not restricted to, customer satisfaction, continuous improvement, and environmental impact. Continuous improvement addresses waste in the business design and manufacturing processes, which could lead to improved profit margins. The sustainability of quality improvement programmes remains a challenge. Causality can be studied, using Six Sigma tools, to relate cause and effect. But these tools do not always allow the user to study and understand feedback from other factors, such as soft human issues, in the improvement process system, typically referred to as 'feedback causality'. System dynamics may improve this understanding. Quality improvement programmes in the heavy engineering manufacturing environment are not researched to the same degree as those in the automotive manufacturing environment. The purpose of this paper is to share results from research into the sustainability of quality improvement programmes, and the development of an appropriate system dynamics model, using qualitative case study data gathered and coded in a heavy engineering manufacturing environment.<hr/>Die uitdaging vir organisasies om deurentyd vir aandeelhouers die beste opbrengs op hul belegging te verseker word al hoe moeiliker as gevolg van internasionalisering van die mark. Daar is vele aksies wat 'n firma kan neem om die uitdagings aan te spreek - byvoorbeeld nuwe produk ontwikkeling, vermeerdering van mark kapitalisasie, koste besnoeiingsinisiatiewe, en kwaliteitsbestuur. Laasgenoemde fokus op, maar is nie beperk tot, klant tevredenheid, kontinue verbetering, en omgewingsimpak nie. Kontinue verbetering spreek onder andere vermorsing of oortolligheid in besigheidsontwerp en vervaardigingsprosesse aan, wat kan lei to verbeterde winsmarge. Volhoubaarheid van kwaliteit verbetering programme bly egter 'n uitdaging. Oorsaaklikheid kan bestudeer word deur gebruik te maak van 'Six Sigma' hulpmiddels. Maar hierdie hulpmiddels laat nie altyd die gebruiker toe om terugvoer vanaf ander faktore soos sagte menslike kwessies in die proses verbetering stelsel te bestudeer en verstaan nie. Die gebruik van sisteem dinamika kan hierdie situasie verbeter. Kwaliteit verbetering programme in die swaar vervaardiging omgewing word nie altyd in dieselfde mate nagevors as in die motorvoertuig vervaardiging omgewing nie. Die doel van hierdie artikel is sekere navorsingsresultate t.o.v. die volhoubaarheid van kwaliteit verbetering programme te deel. 'n Tersaaklike sisteem dinamika model is ontwikkel deur gebruik te maak van kwalitatiewe gevallestudie data wat versamel en gekodeer is in 'n swaar vervaardiging omgewing. <![CDATA[<b>The role of supervisor support in predicting employee job satisfaction from their perception of the performance management system: A test of competing models in engineering environments</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2224-78902014000100009&lng=es&nrm=iso&tlng=es Past studies of performance management systems (PMS) have focused more on designing the framework and less on the effect it has on employees. Moreover, employees in developing countries may not be knowledgeable or familiar with PMS. This paper proposes two competing statistical models to examine the roles that supervisor support (SS) has in engineering organisations. It was found that SS is a mediator, but not a moderator, in the relationship between PMS and employee job satisfaction. In other words, SS partially explains why employees have positive perceptions of their jobs based on their evaluation of the current PMS; SS thus enhances the PMS in engineering organisations.<hr/>Vorige studies van prestasiebestuurstelsels het op die ontwerp van die raamwerk, eerder as die effek daarvan op werknemers, gefokus. Verder is werknemers in ontwikkelende lande dikwels nie ingelig en vertroud met prestasiebestuurstelsels nie. Twee meedingende statistiese modelle om die rol van toesighouerondersteuning te ondersoek word voorgestel. Daar is gevind dat toesighouerondersteuning in die verhouding tussen prestasiebestuurstelsels en werksbevrediging 'n bemiddelaar eerder as 'n moderator is. Toesighouerondersteuning verduidelik dus hoekom werknemers positiewe persepsies van hulle werksgeleenthede koester, gegrond op hul evaluering van die huidige prestasiebestuurstelsel. Toesighouerondersteuning bevorder dus die prestasiebestuurstelsel in ingenieursfirmas. <![CDATA[<b>Direct slicing approach for the production of perfused components by laser beam melting</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2224-78902014000100010&lng=es&nrm=iso&tlng=es In this paper, laser beam melting technology is applied to the manufacture of defined porous metal structures using the exposure strategies of the machine manufacturer. It turns out that specific filter characteristics such as density, permeability, pore size, porosity, and shear strength are comparable to conventionally-made porosities [1]. To overcome some restrictions imposed by the default settings of the machine manufacturer, and to manufacture ultra-lightweight products, our own investigations - such as direct slicing -lead to an alternative exposure strategy for the laser. Here unique exposure lines, with their corresponding start and end points, are individually designed according to their practical needs. Even though this procedure is very complex and time-consuming, it leads to new possibilities for the perfusion of liquid or gaseous fluids that run through metal walls. In summary, the adjustment of the functional porosity of laser beam melted parts made of metal material is the focus of this investigation; and with it, the variation and determination of the proper process parameters is essential. With the easily adjustable porosities and pore sizes that are investigated, combined with the geometric freedom of laser beam melting, very complex elements can be integrated into one part; and this also leads to new fields of application.<hr/>Laserstraal smelttegnologie word toegepas op die vervaardiging van gedefinieerde poreuse metaalstrukture deur die gebruik van die blootstellingstrategieë van die toerustingvervaardiger. Die blyk dat spesifieke filtereienskappe soos digtheid, deurlaatbaarheid, poreusheid en skuifsterkte vergelykbaar is met konvensioneel vervaardigde poreushede. Om sommige beperkings as gevolg van die vervaardiger se verstekverstellings te oorkom en om ultraligte produkte te vervaardig is 'n alternatiewe blootstellingstrategie vir die laser ontwikkel. Unieke blootstellinglyne, met hulle ooreenstemmende begin- en eindpunte, is individueel ontwerp volgens hulle praktiese behoeftes. Al is hierdie prosedure ingewikkeld en tydrowend, lei dit tot nuwe moontlikhede vir die perfusie van vloeistof of gasagtige vloeiers wat deur metaalwande vloei. Opsommend, die fokus van die ondersoek is die verstelling van die funksionele porositeit van laserstraal gesmelte metaal onderdele, en saam met dit, is die variasie en bepaling van die gepaste proses parameters noodsaaklik. Met die maklik verstelbare porositeit wat hier ondersoek word, tesame met die geometriese vryheid van laserstraal smelting, kan komplekse elemente in een onderdeel geïntegreer word, en dit gee aanleiding tot nuwe toepassings. <![CDATA[<b>Adapting modern portfolio theory for prioritising asset care planning in industry</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2224-78902014000100011&lng=es&nrm=iso&tlng=es Productivity improvement within any organisation can lead to increased turnover. This study focuses on developing a maintenance productivity improvement model that is based upon an established financial investment portfolio technique known as the Modern Portfolio Theory (MPT). The model can be used as a tool to minimise and diversify the long term risk associated with variances or fluctuations in the increase in productivity in multiple maintenance service centres. This is achieved by optimising the most efficient way of splitting resources, such as time and money, between these multiple service centres, resulting in increased productivity and a more constant maintenance work load. This model is verified through the use of an efficient frontier, resulting in a graphical method to determine the link between the expected increase in productivity and the standard deviation of the increase in productivity. Ultimately this model can be adapted for use in many sectors within an organisation, over and above the application in maintenance prioritisation. This study concludes that the model offers a simple tool to aid decision-making among various combinations of assets within a maintenance context; and this model, adapted from MPT, was successfully validated with the use of an efficient frontier.<hr/>'n Verbetering in produktiwiteit kan lei tot groei in omset in enige organisasie. Die fokus van hierdie studie is die ontwikkeling van 'n produktiwiteitsverbeteringsmodel in instandhouding. Die model is gebaseer op die gevestigde finansiële beleggings portefeulje tegniek bekend as die 'Moderne Portefeulje Teorie' (MPT). Die model kan gebruik word om die langtermyn risiko as gevolg van afwykings en/of verwisselinge in die produktiwiteit van verskeie onderhoudswerkswinkels te verminder en/of te diversifiseer. Die verbetering kan bereik word deur die optimering van die mees doeltreffende manier om hulpbronne te verdeel tussen verskeie dienssentrums. 'Hulpbronne' kan byvoorbeeld tyd of geld wees. Die optimering lei tot 'n verbetering in produktiwiteit van 'n organisasie sowel as 'n meer konstante werkslading vir die onderhoudswerkswinkels. Die model is geverifieer met die gebruik van 'n doeltreffende begrensing wat lei tot 'n grafiese voorstelling om die verband tussen die verwagte toename in produktiwiteit en die standaard afwyking van die toename in produktiwiteit te bepaal. Die toekomstige vooruitsig vir hierdie model is dat dit kan aangepas word om van toepassing te wees in vele segmente van 'n organisasie. Die resultate van hierdie studie toon dat hierdie model as 'n eenvoudige instrument kan gebruik word om met die besluitneming in verband met die onderhoud van verskeie kombinasies van bates te vergemaklik. Die resultate toon dat die model, wat gebaseer is op die MPT, suksesvol geverifieer is deur die gebruik van 'n doeltreffende grens. <![CDATA[<b>Criteria for selection and gate reviews of technology innovation projects</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2224-78902014000100012&lng=es&nrm=iso&tlng=es This paper describes appropriate project selection criteria and gate review-point criteria for government agencies that fund technology innovation projects in South Africa. Data was gathered via a Delphi survey in which seven expert respondents participated. The most significant project selection criteria and relevant gate reviewing criteria were established. The proposed basic framework consists of fourteen selection criteria, their associated weights, and forty relevant gate reviewing criteria. Commercial risk and feasibility was considered the most important criterion, followed by the team's skills and competence in second place. The use of these criteria when considering investment in technology innovation projects could improve the likelihood of commercial success.<hr/>Hierdie artikel beskryf, vir staatsinstansies wat projekte vir tegnologiese innovasie in Suid Afrika befonds, toepaslike kriteria vir die seleksie van projekte en vir oorsig by hersieningspunte aan die einde van projek fases. Data is ingewin deur middel van 'n Delphi-opname waaraan sewe deskundige respondente deelgeneem het. Die mees beduidende kriteria vir seleksie en oorsig is bepaal. Die voorgestelde raamwerk bestaan uit veertien seleksie-kriteria, relatiewe gewigte vir elk, en veertig kriteria vir hersiening by oorsigpunte. Kommersiële risiko en doenbaarheid word beskou as die belangrikste kriterium, wat gevolg word deur die span se vaardigheid in die tweede plek. Die gebruik van hierdie kriteria wanneer investering in projekte vir tegnologiese innovasie oorweeg word, kan die waarskynlikheid van kommersiële sukses verhoog. <![CDATA[<b>The development of a theoretical lean culture causal framework to support the effective implementation of lean in automotive component manufacturers</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2224-78902014000100013&lng=es&nrm=iso&tlng=es Although it is generally accepted that lean manufacturing improves operational performance, many organisations are struggling to adapt to the lean philosophy. The purpose of this study is to contribute to a more effective strategy for implementing the lean manufacturing improvement philosophy. The study sets out both to integrate well-researched findings and theories related to generic organisational culture with more recent research and experience related to lean culture, and to examine the role that culture plays in the effective implementation of lean manufacturing principles and techniques. The ultimate aim of this exercise is to develop a theoretical lean culture causal framework.<hr/>Alhoewel die 'lean' vervaardigings filosofie algemeen aanvaar word as 'n metode om operasionele mededingendheid te verbeter, is daar baie ondernemings wat dit moeilik vind om by die 'lean' filosofie aan te pas. Die doel van hierdie studie was om 'n bydrae te maak tot die toepassing van 'n meer effektiewe strategie vir die toepassing van 'n 'lean' vervaardigings metodologie. Die studie kombineer en integreer bestaande bevindinge en teorie met betrekking tot algemene ondernemingskultuur met nuwe navorsings bevindinge en ervarings in n 'lean' kultuur. Die studie ondersoek ook die rol van kultuur in die effektiewe implementeering van 'lean' vervaardigings tegnieke. Die hoofdoel van hierdie oefening was om 'n teoretiese raamwerk vir 'lean' kultuur oorsake te ontwikkel. <![CDATA[<b>An investigation into trajectory estimation in underground mining environments using a time-of-flight camera and an inertial measurement unit</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2224-78902014000100014&lng=es&nrm=iso&tlng=es One of the most important and challenging tasks for mobile robots that navigate autonomously is localisation - the process whereby a robot locates itself within a map of a known environment or with respect to a known starting point within an unknown environment. Localisation of a robot in an unknown environment is done by tracking the trajectory of the robot on the basis of the initial pose. Trajectory estimation becomes a challenge if the robot is operating in an unknown environment that has a scarcity of landmarks, is GPS-denied, has very little or no illumination, and is slippery - such as in underground mines. This paper attempts to solve the problem of estimating a robot's trajectory in underground mining environments using a time-of-flight (ToF) camera and an inertial measurement unit (IMU). In the past, this problem has been addressed by using a 3D laser scanner; but these are expensive and consume a lot of power, even though they have high measurement accuracy and a wide field of view. Here, trajectory estimation is accomplished by the fusion of ego-motion provided by the ToF camera with measurement data provided by a low cost IMU. The fusion is performed using the Kalman filter algorithm on a mobile robot moving on a 2D planar surface. The results show a significant improvement on the trajectory estimation. A Vicon system is used to provide groundtruth for the trajectory estimation. Trajectory estimation only using the ToF camera is prone to errors, especially when the robot is rotating; but the fused trajectory estimation algorithm is able to estimate accurate ego-motion even when the robot is rotating.<hr/>Een van die belangrikste en uitdagendste take vir mobiele robotte om selfstandig te kan navigeer is lokalisering. Lokalisering van 'n robot in 'n onbekende omgewing word gedoen deur die volg van die trajek van die robot (die aanvanklike posisie moet bekend wees). Trajekskatting raak uitdagend as die robot moet funksioneer in 'n onbekende omgewing met 'n tekort aan landmerke, geen GPS opvangs, baie swak of geen verligting en 'n gladde oppervlak - soos in ondergrondse myne. Hierdie artikel poog om die probleem van die skatting van 'n robot se trajek in ondergrondse mynbou omgewing met 'n tyd-van-vlug kamera en traagheid meet eenheid op te los. In die verlede is hierdie probleem aangespreek deur die gebruik van 'n 3D laserskandeerder. 3D laserskandeerders is duur en gebruik baie krag, al is hulle baie akkuraat met 'n wye veld van sig. In hierdie artikel is trajek skatting gedoen deur die samesmelting van die ego-beweging, gekry van die TVV kamera, en die meting data voorsien deur 'n goedkoop TME. Die samesmelting is uitgevoer deur gebruik te maak van die Kalmanfilter algoritme op 'n mobiele robot wat in 'n 2D plat vlak beweeg. Die resultate toon 'n verbetering op die trajekskatting. 'n Vicon stelsel word gebruik om die begin posisie te verskaf vir die trajekskatting. Trajekskatting slegs met die behulp van die TVV kamera is geneig tot foute, veral wanneer die robot draai. Die trajekskatting algoritme is in staat om akkuraat ego-beweging te skat, selfs wanneer die robot draai. <![CDATA[<b>A simplified numerical decision-making methodology for physical asset management decisions</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2224-78902014000100015&lng=es&nrm=iso&tlng=es The management of physical assets has become a popular field recently, and is acknowledged in many disciplines worldwide. Physical Asset Management (PAM) is a complex subject that requires the participation of many disciplines. Maintenance management, together with accurate and effective decision-making, is vital for achieving successful PAM. The primary objective of this research project was to identify the possibility of simplifying maintenance-related decision-making. With the focus on numerical decision-making techniques, the secondary objective was to investigate the practicality and useability of combining appropriate techniques to create an easily useable and understandable methodology to support maintenance-related decisions. The results confirm the practicality and useability of a simplified numerical decision-making methodology. By concentrating on the core operational questions related to maintenance, and by combining the most appropriate techniques, a simplified numerical decision-making methodology can ease the decision-making process on an operational level. This can accomplish successful PAM in a proactive, preventive and simplified manner.<hr/>Die onderwerp van Fisiese Bate Bestuur (FBB) het 'n gewilde navorsingsveld geraak oor die afgelope paar jaar. FBB is 'n komplekse onderwerp en vereis insette van verskeie dissiplines. Effektiewe bestuur van instandhouding sowel as doeltreffende besluitneming is noodsaaklik vir suksesvolle FBB. Die primêre doel van hierdie navorsingsprojek was om die moontlikheid van vereenvoudigde besluitneming met betrekking tot instandhouding, te ondersoek. Met die fokus op numeriese besluitnemingstegnieke was die sekondêre doel om die praktiese toepassing van 'n gepaste tegniek-kombinasie te ondersoek om uiteindelik 'n maklike, bruikbare en verstaanbare tegniek-kombinasie te skep wat instandhouding verwante besluite kan ondersteun. Die resultate bevestig die bruikbaarheid van 'n eenvoudige numeriese besluitnemings tegniek-kombinasie om die besluitnemingsproses op operasionele vlak te verlig. Deur te konsentreer op instandhouding verwante kern operasionele vrae, en deur die mees gepaste tegnieke te kombineer, kan 'n vereenvoudige numeriese besluitnemingsmetodologie die besluitnemingsproses op operasionele vlak verlig. Dit kan FBB suksesvol op 'n pro-aktiewe, voorkomende en vereenvoudige manier uitvoer. <![CDATA[<b>Cycle time analysis of tipping trailer frame</b>: <b>A case study in a heavy equipment industry</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2224-78902014000100016&lng=es&nrm=iso&tlng=es A key element with which manufacturing industries should concern themselves in respect of cost and efficiency of operation is the cycle time for preparing their products. A reduction in operational time can result in dramatic improvements in both cost and efficiency. Unfortunately, cycle time problems are sometimes difficult to analyse: there are many factors related to this parameter. This paper presents a cycle time analysis of a tipping trailer frame in a heavy equipment industry. The cycle time analysis, based on the cycle time data collected by a time study, together with the use of an Arena software simulation, is outlined. From the results of this study, it was found that the manufacturing cycle time was 56 hours, and that resources were under-utilised.<hr/>Die siklustyd vir die voorbereiding van produkte is krities tot die vervaardiging industrie. 'n Vermindering in die operasionele tyd kan lei tot drastiese verbeterings in beide die koste en doeltreffendheid. Siklustydprobleme is egter dikwels moeilik om te analiseer omdat daar baie faktore is wat dit beïnvloed. Hierdie artikel stel 'n siklustydanalise voor van 'n tiepsleepwaraam in 'n swaartoerustingindustrie. Die siklsustydanalise, gebaseer op gemete siklustyd data saam met 'n Arena simulasie, word bespreek. Die studie het bevind dat die vervaardigingsiklustyd 56 ure was en dat hulpbronne onder benut was. <![CDATA[<b>Quality and safety management systems</b>: <b>Joint action for certification of small firms in an industrial cluster in Brazil</b>]]> http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2224-78902014000100017&lng=es&nrm=iso&tlng=es This paper presents and discusses a proposal for joint action among small firms in an industrial cluster in Brazil for the certification of quality and safety management systems. It proposes a management system model, the implementation process, and periodic auditing. It is the result of an action-research project developed in a metal-mechanical cluster. Its originality lies mainly in the proposal for a joint action programme for the certification of companies, led by the cluster governance agency, to increase the collective efficiency of a cluster. Despite the obstacles encountered, this proposal can help to reduce the difficulties faced by small businesses in implementing and maintaining management systems, and in the long run to foster a culture of quality and safety management. It also contributes to joint actions within the cluster. The challenge faced by the cluster governance agency is to sustain the certification programme in the long term.<hr/>'n Voorstel vir die samewerking van klein industriële firmas in Brasilië met die doel om gehalte- en veiligheidstelsels te sertifiseer word voorgestel en bespreek. 'n Bestuurstelselmodel, die implementeringsproses en 'n periodieke ouditeurstelsel word voorgestel. Dit is die resultaat van 'n aksienavorsingsprojek wat in 'n metaal-meganiesegroep ontwikkel is. Die oorspronklikheid in dié benadering is hoofsaaklik in die voorstel vir samewerking van firmas vir sertifisering doeleindes. Ten spyte van die struikelblokke vergemaklik die voorstel die hantering van probleme ervaar deur klein firmas wanneer hulle bestuurstelsels implementeer en onderhou. Op die lang termyn vestig dit 'n kultuur van gehalte- en veiligheidsbestuur.