The relaxation of international boundaries has enabled the globalisation of markets making available an ever increasing number of specialised suppliers and markets. Inevitably this results in supply chains sharing suppliers and customers reflected in a network of relationships. Within this context firms buyers configure their supply relationships based on their perception of supply risk. Risk is managed by either increasing trust or commitment or by increasing the number of suppliers. Increasing trust and commitment facilitates collaboration and reduces the propensity for a supplier to exit the relationship. Conversely, increasing the number of suppliers reduces dependency and increases the ease of making alternative supply arrangements. The emergent network of relationships is dynamic and complex, and due in no small part to the influence of inventory management practices, tightly coupled. This critical organization of the network describes a system that contrary to existing supply chain conceptualisation exists far from equilibrium, requiring a different more appropriate theoretical lens through which to view them. This thesis adopts a Complex Adaptive Systems (CAS) perspective to position supply networks as tightly coupled complex systems which according to Normal Accident Theory (NAT) are vulnerable to disruptions as a consequence of normal operations. The consequential boundless and emergent nature of supply networks makes them difficult to research using traditional empirical methods, instead this research builds a generalised supply network agent based computer model, allowing network constituents (agents) to take autonomous parallel action reflecting the true emergent nature of supply networks. This thesis uses the results from a series of carefully designed computer experiments to elucidate how supply networks respond to a variety of market structures and permitted agent behaviours. Market structures define the vertical (between tier) and horizontal (within tier) levels of price differentiation. Within each structure agents are permitted to autonomously modify their prices (constrained by market structure) and collaborate by sharing demand information. By examining how supply networks respond to different permitted agent behaviours in a range of market structures this thesis makes 4 contributions. Firstly, it extends NAT by incorporating the adaptive nature of supply network constituents. Secondly it extends supply chain management by specifying supply networks as dynamic not static phenomena. Thirdly it extends supply chain risk management through developing an understanding of the impact different permitted behaviour combinations on the networks vulnerability to disruptions in the context of normal operations. Finally by developing the understanding how normal operations impact a supply networks vulnerability to disruptions it informs the practice of supply chain risk management.

Thesis (MScEng)--University of Stellenbosch, 2004. / ENGLISH ABSTRACT: South Africa, and other developing countries, experience great problems concerning road traffic accidents. Despite road safety campaigns like Arrive Alive being launched, accident rates do not decline significantly and the problem is predicted to get worse. This study is done on a road in the Western Cape, the R44, to investigate the causes of road accidents. The causes of the accidents are deduced from the accident reports and relationships are sought with other factors. The results of this study are risk factors (human-, environment- and vehicle factors) for the 14 accident types that occurred on the R44, as well as measures to prevent road accidents. It has been found that the human factor plays the biggest role in road accidents. Out of the 404 accidents analysed, 77.7% were caused by human factors, 8.7% by unknown factors, 7.2% by environmental factors and 6.4% by vehicle factors. The problems experienced with the data quality are reported and recommendations concerning it are made. / AFRIKAANSE OPSOMMING: Suid-Afrika en ander ontwikkelende lande ervaar groot probleme met verkeersongelukke. Ten spyte van veldtogte soos Arrive Alive wat geloods word, neem ongelukskoerse nie beduidend af nie, en daar word voorspel dat die situasie nie gaan verbeter nie. Hierdie studie is op 'n pad in die Wes-Kaap, die R44, gedoen om die oorsake van padongelukke vas te stel. Die oorsake van ongelukke i s van die ongeluksvorms a fgelei, en verwantskappe is gesoek met ander faktore. Die resultate van die studie is risikofaktore (menslike-, omgewings- en voertuigfaktore) vir die 14 ongelukstipes wat op die R44 voorgekom het, asook voorkomingsmaatreëls om padongelukke te voorkom. Daar is gevind dat die menslike faktor die grootste oorsaak van ongelukke is. Uit die 404 ongelukke wat geanaliseer is, is 77.7% van die ongelukke deur menslike faktore, 8.7% van die ongelukke deur onbekende faktore, 7.2% van die ongelukke deur omgewingsfaktore en 6.4% van die ongelukke deur voertuigfaktore veroorsaak. In hierdie studie is probleme ondervind met die datakwaliteit, en daaroor is verslag gedoen en aanbevelings gemaak.

published_or_final_version / Business Administration / Master / Master of Business Administration

Uppsatsen undersöker orsaker till fenomenet girting, dvs olyckor där bogserbåtar dras ned och potentiellt kapsejsar vid bogsering av farkoster. Undersökningen utgår från 14 officiella haverirapporter om girtingsituationer världen över.  Med hjälp av modellen HFACS-MA kategoriseras olycksorsakerna i en orsakskedja för att utröna vilka kategorier som är mest frekvent förekommande i samtliga undersökta olyckor. Resultatet visar att dåligt förberedda bogseroperationer (med otillräcklig eller utebliven planering och riskbedömning), brister i organisationernas dokumentation (manualer, instruktioner och procedurer), samt bristande kommunikation mellan de inblandade parterna var de största faktorerna för girting. För att minska risken för girting har rekommendationer framtagits, som bl a innefattar vikten av att hålla dokumentation uppdaterad, hålla tydlig kommunikation mellan inblandade parter under bogseringsoperationer samt planera varje operation noggrant och ge alla inblandade möjlighet till återkoppling. / This essay studies the causes of girting, i.e. accidents where tugboats get pulled down and capsizes by the vessel it is towing. The study uses 14 official accident reports about girting accidents all over the world. The HFACS-MA model is used to categorize the causes of the accident into a causal chain, in order to find out which categories are most frequently present in the accident reports.  The result shows that poorly planned tow operations (with inadequate planning and/or risk assessment), deficiencies in the organization’s documentation (i.e. manuals, instructions and procedures), and poor communication between the involved parties were the most frequently found factors for girting. In order to reduce the risk of girting, recommendations have been made that includes the importance of keeping documents up to date, maintain clear communication between the parties involved during towing operations and to plan each operation thoroughly, giving everyone involved the opportunity for feedback regarding the plan.

Cette recherche avait pour objectif de mieux connaître l'épidémiologie des traumatismes par accident de la route chez l'enfant. Pour cela, des analyses ont été réalisées à partir des données d'une grande qualité : le Registre du Rhône. Les incidences de traumatismes routiers chez les enfants ont été calculées. La localisation et la nature des lésions ont été finement décrites, en fonction du type d'usager de la route. Le deuxième objectif était d'identifier des facteurs de risque de traumatisme sévère et de séquelles. Les handicaps secondaires aux traumatismes routiers ont été étudiés à partir d'une étude de cohorte prospective multicentrique conduite dans douze villes françaises, incluant 139 enfants sévèrement traumatisés de la route et admis en réanimation pédiatrique. Les déficiences fonctionnelles, comportementales et cognitives ainsi que les degrés d'incapacités et les retentissements sur la famille et la scolarité, ont été évalués six mois et un an après l'accident. Les différents outils d'évaluation ont montré leur complémentarité pour apprécier la réalité des handicaps. Des facteurs de risque de séquelles à un an ont été identifiés permettant de cibler les enfants qui devraient bénéficier d'une prise en charge et d'un suivi particuliers. Des recommandations pour la prévention ont pu être élaborées, concernant particulièrement l'utilisation des dispositifs de protection en voiture, à deux-roues, les modalités de prise en charge en fonction des facteurs de gravité et les modalités de traitement en phase aiguë.

No description available.

Žemės ūkio sektorius išlieka viena pavojingiausių ekonominės veiklos rūšių pasaulyje, o tuo pačiu ir Lietuvoje. Atlikus sociologinius tyrimus, vienoje anketinėje apklausoje dalyvavo 96 ūkininkai ir bendrovių vadovai, nustačiau, kad dirbant traktoriniams žemės ūkio junginiams, žmonės dažniausiai sužeidžiami, kai mašina eksploatuojama be apsaugų, užvedama neišjungus pavaros, žmonės vežami priekaboje ir kai technika eksploatuojama ne pagal paskirtį. Kitoje anketinėje apklausoje dalyvavo 241 žemės ūkio darbuotojai, nustatėme, kad samdomi žemės ūkio darbuotojai labiau nei ūkininkai toleruoja rizikingą veiklą žemės ūkio traktorinių junginių darbo zonose. Trečioje anketinėje apklausoje dalyvavo 138 žemės ūkio technikos operatoriai, nustatyta, kad instruktavimas nepadeda suprasti pavojus traktorių ir žemės ūkio mašinų pavojingose zonose nurodė 30,4 proc. apklaustų žemės ūkio technikos operatorių. / The agricultural sector remains one of the most dangerous types of economic activities in the world, while at the same time, and Lithuania. Following the sociological studies, one questionnaire survey involved 96 farmers participated in the company and executives, found that working in the agricultural tractor combinations, people most often injured when the machine is operated without the guards, opened the drive off, people are transported in the trailer where the technique of operation and not by purpose. In another questionnaire survey involved 241 agricultural workers, found that employed agricultural workers, farmers, rather than tolerate the risky business of agricultural tractor units of work zones. The third questionnaire survey involved 138 agricultural machinery operators, found that the instruction does not understand the dangers of tractors and agricultural machinery in hazardous areas indicated 30.4 percent. surveyed agricultural machinery operators.

The investigation and modelling of aviation accident causation is dominated by linear models. Aviation is, however, a complex system and as such suffers from being artificially manipulated into non-complex models and methods. This thesis addresses this issue by developing a new approach to investigating aviation accident causation through information networks. These networks centralise communication and the flow of information as key indicators of a system‟s health and risk. The holistic approach focuses on the system itself rather than any individual event. The activity and communication of constituent elements, both human and non-human agents, within that system is identified and highlights areas of system failure. The model offers many potential developments and some key areas are studied in this research. Through the centralisation of barriers and information nodes the method can be applied to almost any situation. The application of Bayesian mathematics to historical data populations provides scope for studying error migration and barrier manipulation. The thesis also provides application of these predictions to a flight simulator study in an attempt of validation. Beyond this the thesis also discusses the applicability of the approach to industry. Through working with a legacy airline the methods discussed are used as the basis for a new and forward-thinking safety management system. This holistic approach focuses on the system environment, the activity that takes place within it, the strategies used to conduct this activity, the way in which the constituent parts of the system (both human and non-human) interact and the behaviour required. Each stage of this thesis identifies and expands upon the potential of the information network approach maintaining firm focus on the overall health of a system. It is contended that through the further development and application of this approach, understanding of aviation risk can be improved.

Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal.

Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal.