| 1. |
- Andersson, Thomas, 1970-, et al.
(författare)
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Easier to trust managers than management? : The case of improvement work in healthcare
- 2011
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Konferensbidrag (refereegranskat)abstract
- Previously, improvement work in healthcare has mainly been medically related and driven by medical research, but NPM implies that management-initiated improvement work targeting organizing, productivity, efficiency, work flow etc. has become more and more common. Management-initiated improvement work has a high failure rate, and in general it seems difficult to motivate co-workers to actively participate. In all processes of organizational change, trust in the initiator of a change project is an important prerequisite to enable change take place. In this article, our purpose is to investigate how trust in management influences management-initiated improvement work. In a qualitative study we investigate improvement work at three Swedish hospitals. Our theoretical framework is based on a view of management as being both the people who manage and the system of management. This distinction is important since we can trust people and we can have confidence in a system, but these processes are different. Consequently, it is possible to trust individual managers, but as long as we do not trust management as a system, management-initiated improvement work will face considerable problems. To analyze trust we use a model that identifies three important antecedents for one person (the trustor) to consider another person (the trustee) as trustworthy: ability, benevolence and integrity. Using social system theory, we extend this model to on the one hand describe trust in specific persons (specific managers), and on the other hand describe confidence in a system (management in general, which the system-specific managers are parts of). The results indicate that there in general is a lack of trust between healthcare personnel and healthcare management. We were able to find certain managers who were found trustworthy by the personnel, but despite these trust-relations the personnel did still not have confidence in management as a system. To the contrary, these managers were perceived as exceptions, and did not change the perception of management in general. The consequences for management-initiated improvement work were that most personnel at best were ignorant to it, and at worst resisted it openly. However, there were examples when trusted enthusiastic managers succeeded in initiating improvement work, but then the continuation and success was directly connected to this person, and if s/he left, the improvement work stopped. Furthermore, some work groups seemed to very clearly separate “real” improvement work, which they initiated themselves, from “phony” improvement work initiated by management, which only stole time from more important tasks.
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| 2. |
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| 3. |
- Andersson, Thomas, 1970-, et al.
(författare)
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Organisering av förbättringsarbete inom vården med inspiration från industrin
- 2011
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Konferensbidrag (refereegranskat)abstract
- I denna artikel fokuserar vi på användandet av industriellt baserade produktionssynsätt (IBP) inom vården i avsikt att arbeta systematiskt med förbättringsarbete. Tidigare forskning har visat att det är svårt att få nya arbetsmetoder att få genomslag i den dagliga praktiken. I denna artikel fokuserar vi på om det går att se indirekta effekter såsom hur förbättringsarbetet organiseras beroende på vilka IBP olika sjukhus väljer att arbeta med. Undersökning är genomförd genom fallstudier på tre sjukhus som har valt att arbeta med tre olika metoder: six sigma, processorientering och mikrosystem.Studien visar att de olika logikerna bakom de olika metoderna ger fundamentalt olika sätt att organisera förbättringsarbetet vid de tre sjukhusen. Six sigma-sjukhuset valde ett centraliserat förbättringsarbete i hög grad drivet av experter på förbättringsmetoder, processsjukhusethade en expertavdelning som var mer av bollplank och utbildare för verksamhetens förbättringsarbete och mikrosystem-sjukhuset valde ett decentraliserat förbättringsarbete där förbättringsarbetet var både lokalt initierat och drivet.
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| 4. |
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| 5. |
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| 6. |
- Eriksson, Nomie, 1955-, et al.
(författare)
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Fiery Spirits in the context of institutional entrepreneurship in Swedish healthcare
- 2015
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Ingår i: Journal of Health Organization & Management. - : Emerald Group Publishing Limited. - 1477-7266 .- 1758-7247. ; 29:4, s. 515-531
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Tidskriftsartikel (refereegranskat)abstract
- Purpose – Clinical governance and leadership concepts can lead to more or less successfulimplementations of new clinical practice. The purpose of this paper is to examine how Fiery Spirits, asinstitutional entrepreneurs can, working in a team, implement sustained change in hospital clinicalpractice.Design/methodology/approach – This paper describes two case studies, conducted at two Swedishhospitals over a period of two years, in which changes in clinical practice were implemented. In bothcases, key-actors, termed Fiery Spirits, played critical roles in these changes. The authors use aqualitative approach and take an intra-organizational perspective with semi-structured in-depthinterviews and document analysis.Findings – The new clinical practices were successfully implemented with a considerable influenceof the Fiery Spirits who played a pivotal role in the change efforts. The Fiery Spirits persuasively,based on their structural and normative legitimacy and the adoption of learning processes, advocated,and supported change.Practical implications – Fiery Spirits, given flexibility and opportunity, can be powerful forcesfor change outside the trajectory of management-inspired and management-directed change.Team members, when inspired and encouraged by Fiery Spirits, are less resistant to change and morewilling to test new clinical practices.Originality/value – The paper complements literature on how the Fiery Spirit concept aligns withconcepts of clinical governance and leadership and how change can be achieved. Additionally, thefindings show the effects of legitimacy and learning processes on change in clinical practice.
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| 7. |
- Eriksson, Nomie, et al.
(författare)
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Involvement Drivers : A Study of Nurses and Physicians in Improvement Work
- 2016
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Ingår i: Quality Management in Health Care. - : Lippincott Williams & Wilkins. - 1063-8628 .- 1550-5154. ; 25:2, s. 85-91
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Tidskriftsartikel (refereegranskat)abstract
- This article reports on the involvement of nurses and physicians in improvement work, with a special focus on the drivers. The purpose was to describe how the nurse and physician groups understand involvement drivers for improvement work and to explain the differences in how they understand involvement. The study was conducted at 2 Swedish hospitals, and a total of 20 nurses and 10 physicians were interviewed. The theoretical framework, developed by an interpretative approach, identifies and describes a number of involvement drivers. On clustering the drivers into larger involvement factors, the study shows clear differences and profiles in terms of the 2 groups' perception and understanding of the involvement—drivers. Each group's profile was then analyzed on the basis of concept of professional culture.
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| 8. |
- Evansluong, Quang, et al.
(författare)
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The family influences of EO development in immigrant family businesses
- 2018
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Ingår i: Sustainable entrepreneurship. - Toledo.
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Konferensbidrag (refereegranskat)abstract
- This paper explores how family influences the entrepreneurial orientation (EO) process in immigrant family business. To fulfill the purpose, we employ inductive multiple case studies with in-depth interviews. We rely on seven cases of immigrant entrepreneurs of Chinese, Icelandic, Turkish, Cameroonian, Mexican and Lebanese who established firms in Sweden. Our results suggest that EO development trajectories vary in regard to first and second immigrant entrepreneurs, low and high-tech sectors and host and home countries. Thus, family dynamics facilitates the development of entrepreneurial orientation over time through transforming, translating and transferring across generations and contexts. Our study indicates that, through family dynamics, EO is developed as a (1) transferring process of the founders’ proactiveness between the family in the home and host country;(2) translating process of risk-taking between the family companies in the home country to immigrant family company in the host country and (3) transforming process of innovativeness between the home and the host country.
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| 9. |
- Hilletofth, Per, et al.
(författare)
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Agent-based decision support for maintenance service provider
- 2010
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Ingår i: International Journal of Services Sciences. - : Inderscience Enterprises Ltd.. - 1753-1446 .- 1753-1454. ; 3:2/3, s. 194-215
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Tidskriftsartikel (refereegranskat)abstract
- Operations performed by a maintenance service provider (MSP) can include the entire maintenance function or select activities; these need to be well-balanced in terms of utilisation rate of own resources, maintenance cost incurred and the uptime of the customers’ production systems. MSPs face challenges due to the task of planning several non-associated plants and with a frequent lack of reliable information. In this research work, an agent-based decision support system of service-related maintenance has been developed. Research shows that this approach can improve the understanding of the problem domain and also generate a basis for decision-making and structural changes.
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| 10. |
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| 11. |
- Hilletofth, Per, et al.
(författare)
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Agent-based decision support in maintenance service operations
- 2009
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Ingår i: Proceedings of the 16th International Annual EurOMA Conference.
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Konferensbidrag (refereegranskat)abstract
- In this research an agent-based decision support system for service related maintenancehas been developed, the maintenance planning is complex including corrective andpreventive tasks of several non-associated plants. This type of problem is well suited formodeling and implementation using Agent-Based Modeling and Simulation (ABMS).The simulation model enables decision-makers to iteratively set parameters, runsimulations and evaluate results. Research shows that this approach can improve theunderstanding of the problem domain and also generate a basis for decision-making.
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| 12. |
- Hilletofth, Per, et al.
(författare)
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Agent-Based Simulation Fusion for Improved Decision Making for Service Operations
- 2009
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Ingår i: Proceedings of the 12th International Conference on Information Fusion. - : IEEE. - 9780982443804
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Konferensbidrag (refereegranskat)abstract
- We use agent-based modeling and simulation to fuse data from multiple sources to estimate the state of some system properties. This implies that the real system of interest is modeled and simulated using agent principles. Using Monte-Carlo simulation, we estimate the values of some decision-relevant numerical properties, such as utilization of resources and service levels, as a decision support for a Maintenance Service Provider. Our initial results indicate that this kind of fusion of information sources can improve the understanding of the problem domain (e.g. to what degree some critical properties influence service operations) and also generate a basis for decision-making.
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| 13. |
- Hilletofth, Per, et al.
(författare)
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Agent-based simulation fusion for improved decision making for service operations
- 2009
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Ingår i: Proceedings of the 12th International Conference on Information Fusion. - Seattle, US. - 9780982443804 ; , s. 998-1005
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Konferensbidrag (refereegranskat)abstract
- We use agent-based modeling and simulation to fuse data from multiple sources to estimate the state of some system properties. This implies that the real system of interest is modeled and simulated using agent principles. Using Monte-Carlo simulation, we estimate the values of some decision-relevant numerical properties. We use the estimated properties, such as utilization of resources and service levels, as a decision support for a Maintenance Service Provider. Our initial results indicate that this kind of fusion of information sources can improve the understanding of the problem domain (e.g. to what degree some critical properties influence service operations) and also generate a basis for decision-making.
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| 14. |
- Hilletofth, Per, et al.
(författare)
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Differentiated Supply Chains Strategies Based on Customer Insights
- 2008
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Ingår i: Proceedings of the 18th International Conference on Flexible Automation and Intelligent Manufacturing (FAIM 2008), Skövde, 30/6-2/7, 2008..
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Konferensbidrag (refereegranskat)abstract
- Supply chains satisfy customers by striving for delivering the right products to the right place at the right time, atthe right quality and at the right quantity within an increasingly faster pace and lower cost. One implication thatcan be made from this is that the nature of markets is the point of departure in both supply chain design andoperations. Given that organizations usually offer a wide range of products and services with different supplyand demand characteristics, one could argue that organizations conduct business in various types of noncoherentbusiness environments. There has been a recognition that ‘one-size-fits-all’ supply chain strategies onlysatisfies a limited number of business environments, and that it is increasingly necessary to develop severaldifferentiated supply chain strategies to satisfy all major business environments in a better way. This paperemploys a descriptive case study approach to illustrate how a case company develops differentiated supplychains based on customer insights. Case study findings reveal that one efficient way to develop differentiatedsupply chain strategies is to combine different supply and delivery methods into supply chain solutions. Bycombining relatively few supply and delivery methods it is possible to develop several differentiated supply chainstrategies.
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| 15. |
- Hilletofth, Per, et al.
(författare)
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Information fusion in maintenance planning
- 2007
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Ingår i: Proceedings of Swedish Production Symposium. - Göteborg, Sweden.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Industrial production service organisations, companies maintainingproduction machines and whole processes as well as factories, are in great demand ofproductivity and profitavility improvement. Usually performance in theseorganisations arises from high utilization of personnel, superior engineeringknowledge and purchasing expertise/power. However, small and medium sizedmaintenance service providers mostly differate themselves with two first mentioneditems. In this paper we will propose information fusion cockpit to be used in theSME maintenance organisation to enhance problem solving, demand visibility andresource need estimates – hopefully this will enhance the performance of a caseorganisation. As a key input variable to manage large amount of different customerswe identify incoming calls to trigger information collection from vast number ofdifferent databases – the integration of this incoming “demand” is the first step to betaken in the use of more advanced systems. We also speculate in this paper, howagent based artificial intelligence could be used in order to take full benefit frommore advanced system.
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| 16. |
- Hilletofth, Per, et al.
(författare)
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Integration and formalization of strategic product development and commercialization in a manufacturing company : A challenge for supply chain management
- 2008
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Ingår i: Proceedings of the 18th International Conference on Flexible Automation and Intelligent Manufacturing. - Skövde : University of Skövde. - 9789163327575 ; , s. 532-539
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Konferensbidrag (refereegranskat)abstract
- The last decades a new type of business environments has evolved characterized by rapid and volatile demand changes, short product life cycles, and high levels of customized products. The competitiveness of a business in these environments is mostly determined by its responsiveness. This is characterized by the ability to quickly scale up or down the production volume, the presence of an innovative and fast product development, and a quick incorporation of consumer requirements into the product development. This paper employs a descriptive case study approach to illustrate how product development and commercialization can be integrated into a product management flow to realize innovative and faster product development. Case study findings reveal that the case company has during a five year period increased the number of successful product introductions. Furthermore, the studied approach proves to be successful in this mature business environment where it is essential to develop products based on the consumer need and behaviour and to differentiate the product assortment. Based on our case study we also recognize that the product management flow does not concern supply chain management (SCM) to some extent in the case company – this indicates that further development is needed in SCM applications to support product life-cycle based managerial processes.
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| 17. |
- Hilletofth, Per, et al.
(författare)
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Teaching ERP in logistics curriculum : a case experience from Sweden
- 2010
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Ingår i: International Journal of Business Information Systems. - : InderScience Publishers. - 1746-0972 .- 1746-0980. ; 6:3, s. 295-314
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Tidskriftsartikel (refereegranskat)abstract
- The use of ERP systems in business is commonplace and often a requirement for rapid and efficient operations. The presence of ERP in higher education can be seen as a prerequisite for students to achieve necessary skills and knowledge, but how can the education be achieved in a better way? In this research, the use of ERP systems as a part of two courses of the logistics curriculum in higher education at a Swedish University are presented and analysed. The traditional approach of teaching logistics, where computer sessions are incorporated in ordinary courses, is being compared to a new intensive and flexible course format dedicated entirely to ERP education with a stronger focus on problem-oriented learning. The results show that both approaches offer opportunities, the traditional approach allows students to receive both theoretical and practical knowledge and skills, while the intensive approach provides them with significant practical knowledge and skills. This research results leaves us arguing that the best combination is to utilise both approaches to establish the needed basis for curriculum.
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| 18. |
- Hilmola, Olli-Pekka, et al.
(författare)
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Deregulation of Railroads and future development scenarios in Europe
- 2007
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Ingår i: World Review of Intermodal Transportation Research (WRITR). - : InderScience. - 1749-4729 .- 1749-4737. ; 1:2, s. 146-169
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Tidskriftsartikel (refereegranskat)abstract
- A decade ago, the European Union decided that railways should be privatised and deregulated (effective from 2007 onwards). Due to the recent enlargements of the EU and the risk of failures in the decision-making process, it is important to examine early adopters of deregulation policies. We analyse literature and use second-hand quantitative material to thoroughly review this process concerning three different countries (USA, UK and Sweden). In all three cases, the deregulation process has brought positive performance improvements in the long-term perspective, but in the short to medium term, there are a number of problems and warning examples, especially arising from UK case.
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| 19. |
- Hilmola, Olli-Pekka, et al.
(författare)
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From Northern Europe to Russia and Asia, and Vice Versa : Traffic Flow Analysis – Current Situation and Development trends
- 2006
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Ingår i: Proceedings of the 8th International Conference on Industrial Logistics, ICIL '2006. - Kaunas : Technologija. - 9955250828 - 9789955250821 ; , s. 96-107
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Konferensbidrag (refereegranskat)abstract
- Large amounts of European manufacturers have enlarged their manufacturing networks to Asia, in most of the occasions to China and India. Also the growing demand in Asia as well as in Russia creates increasing need for cost efficient and lead time wise supply chain solutions. It depends on the used manufacturing and supply chain strategy, whether manufacturing units in a company's network use market focused (factory in particular region serves that market needs) or product group based (one manufacturing unit takes global delivery responsibility) control. In either case, manufacturers at the moment use "local sourcing" strategy to enhance supply chain control and responsiveness. However, this approach is incapable to use global sourcing opportunities, and utilize cheap raw materials and semi-finished items from Asia and Russia to be used in European manufacturing units. The constraints in this process are the transportation costs and delays; sea container transportation from Asia is cheap, but takes long time to be shipped to Europe (nearly two months), and correspondingly air transportation is expensive, and sets restrictions for the package size and weight. At the moment a third alternative also exist, where items are transported between Europe, Russia and Asia through Trans-Asian Railway network. This route provides moderate cost efficiency (as compared to air transportation) and lead time advantage (as compared to sea containers).In this paper we analyze the survey research results, which was targeted on the largest manufacturers and retailers in Finland and Sweden. Based on the survey analysis, we estimate how transportation modal split (between road, sea, railway and air) will evolve in the future, and how traffic flows develop between Europe, Russia, South-Korea, India, China, and Japan. We also present estimation from the future transportation costs development. In the analysis phase we also consider, how large volumes could be shifted to railway connection, and how wise customer picking could smoothen the transportation amounts from and to Russia/Asia. Also avenues for further research are being proposed based on our quantitative analysis.
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| 20. |
- Hilmola, Olli-Pekka, et al.
(författare)
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From Northern Europe to Russia and Asia, and vice versa : traffic flow analysis – current situation and development trends
- 2010
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Ingår i: International Journal of Logistics Systems and Management. - : InderScience Publishers. - 1742-7967 .- 1742-7975. ; 6:2, s. 205-217
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Tidskriftsartikel (refereegranskat)abstract
- European manufacturers have enlarged their manufacturing networks to Asia. Also, the growing demand in Asia as well as in Russia creates challenge for supply chain solutions. This research presents survey research results, targeted on the largest manufacturers and retailers in Finland and Sweden. We estimate how transportation modal split (road, sea, railway and air) will evolve in the future, and how traffic flows will develop between Europe, Russia, and Asian countries. We also present an estimation of the future transportation costs development. In the analysis phase, it is also considered how large volumes could be shifted to favour railway connection.
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| 21. |
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| 22. |
- Jäger, Kerstin, et al.
(författare)
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From standard 3PL provider to service developer : a case study from the Swedish furniture industry
- 2009
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Ingår i: World Review of Intermodal Transportation Research (WRITR). - : InderScience Publishers. - 1749-4729 .- 1749-4737. ; 2:4, s. 376-390
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Tidskriftsartikel (refereegranskat)abstract
- The strong competition between companies has resulted in an increased outsourcing of activities that are not considered core activities. This has created an emerging business opportunity in logistics, attracting several new actors and companies to enter the market and fill the demand for new services. These actors represent several types of providers who are often called Third-Party Logistics (3PL) providers. The purpose of this study is to investigate the environment of a 3PL provider that also develops services. The focus is particularly on how the provider has evolved and identifying the key issues on how to be successful in the 3PL industry. The primary research strategy is a descriptive embedded single case study. The findings reveal that the case company has evolved from being a standard 3PL provider to a service developer, since it, in addition to traditional services, nowadays also provides more value-added services. These services involve a set of more standardised activities that can be combined according to each customer's wishes and requirements. The findings also reveal that the main requirements to be a successful service developer are a clear customer understanding and focus, value-added and customised services and reliable deliveries (both in terms of time and a low percentage of damaged goods), as well as the utilisation of Information and Communications Technology (ICT).
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| 23. |
- Jäger, Kerstin, et al.
(författare)
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Logistics actors : Key issues for a service developer
- 2008
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Ingår i: Proceedings of the 18th International Conference on Flexible Automation and Intelligent Manufacturing. - Skövde, Sweden. ; , s. 1329-1336
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Konferensbidrag (refereegranskat)abstract
- The very hard competition between companies have resulted in an increased outsourcing of many activities thatare not considered to be core activities, or main business processes. This has created an emerging businessopportunity attracting many new actors, companies, to enter the market and fill the demand for new services.Logistics is one example of activities not seen as core competence in many companies; in this paper we use adescriptive case study approach to illustrate the requirements to succeed as such a logistics service provider.Primarily this requires a close relationship between the actors and trust and openness are important factors tomaintain. The kind of relationship, the exchange of information, the nurturing of trust and the service ofinformation systems has to be solved. The case-study is based on a company, LBC, which acts as a logisticsservice developer, and the focus is on the services provided and the company’s view of the customer relationship.Findings reveal that logistics service developer to a large extent needs to focus on the customer and continuouslydevelop their service range to offer improved/new services. We have found that LBC has gone from a traditional3PL to become a service developer and provide customized services according to every single customers need.The most important is to have a starting point from the view of the customer. LBC solve this, among other things,with a personal contact to every customer. According to the literature one could segment different logisticsactors into four categories.
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| 24. |
- Jäger, Kerstin, et al.
(författare)
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Logistics actors - Key issues for a service developer
- 2008
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Ingår i: Proceedings of the 18th International Conference on Flexible Automation and Intelligent Manufacturing FAIM 2008. - Skövde, Sweden : University of Skövde. - 9789163327575 ; , s. 1329-1336
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)
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| 25. |
- Jäger, Kerstin, et al.
(författare)
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Operating as a third-party logistics integrator without any distribution operations ownership
- 2007
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Ingår i: International Journal of Services and Standards. - : InderScience Publishers. - 1740-8849 .- 1740-8857. ; 3:2, s. 154-168
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Tidskriftsartikel (refereegranskat)abstract
- Third-Party Logistics (3PL) providers have usually developed themselves through transportation ownership (mainly road or sea), and/or warehousing/freight forwarding capability. However, among these actual operations, there exists a number of other routes, e.g. by offering administrative/indirect work of sales, purchasing, business control and inventory management. With increased service level expectations among OEMs, there is a clear need for these kinds of well-defined and performed non-tangible logistical services. In this paper three case studies are presented, which show that a 3PL integrator could arise from this new service context, and could operate all logistical issues, even without any distribution operations ownership.
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| 26. |
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| 27. |
- Jäger, Kerstin, et al.
(författare)
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The Future of Third-Party Logistics : Key Issues for a Logistics Integrator
- 2006
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Ingår i: Contemporary Research Issues in International Railway Logistics. - Kouvola : Lappeenranta University of Technology. - 9522142255 - 9522142263 ; , s. 67-87
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Bokkapitel (refereegranskat)abstract
- Logistics has increasingly been recognized as a vital part of an organization’s competitive resources. With an increased outsourcing of the logistics function, due to increasing competition and high customer expectations on service-level, there is a need for more professional and well-equipped logistics services. This need is emphasized by the tendency that competition increasingly takes place between supply-chains more than between companies. There is a development of actors, known as third-party logistics providers or logistics integrators, who can take the role as integrator for several companies in a supply chain. This article focuses on the driving forces of these actors and how they can stay competitive by providing customers specific logistics solutions. A case study is presented of a Logistics Integrator and three of its customers with a varying degree of integrated collaboration in the logistic chain, and some key issues are presented from the provider’s and the customer’s perspective.
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| 28. |
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| 29. |
- Köks, Tönu, et al.
(författare)
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The role of advanced planning systems and simulation in supply/demand chain management
- 2003
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Ingår i: International Conference on Industrial Logistics 2003, Proceedings. - : International Centre for Innovation and Industrial Logistics - ICIIL. ; , s. 313-317
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Konferensbidrag (refereegranskat)abstract
- Discrete-Event Simulation (DES) has become a commonly used tool for the modelling and analysis of logistics. A more novel approach to manufacturing problems is Advanced Planning Systems (APS). These are used in an optimization process for the planning of production, inventory, and transportations often integrated with ERP-systems. Supply/Demand Chains can be approached from a strategic, tactical, or operational level. Simulation tools and APS-systems are different approaches to a similar problem. The simulation approach involves connecting an Enterprise Resource Planning (ERP) system with a simulation system. The simulation system contains a model of the production, and 'real-time'-data is used to produce a realistic production plan, e. g. to minimize waste of resources, or setting more accurate delivery dates. APS-systems are using simultaneous data when considering resource allocation. APS-systems normally use a separate module for calculation and optimization. The optimization activity produces an improved plan where trade-offs are examined. In this paper a conceptual model is proposed and an overview is given on the two software tools, and their advantages and disadvantages. Their usefulness is discussed in the context of physical material flow in Supply Chain (SC). Finally some results and experiences from industrial simulation studies are presented.
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| 30. |
- Moore, Philip, et al.
(författare)
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Intelligent semi-autonomous vehicles in materials handling
- 1999
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Ingår i: Mechatronics (Oxford). - : Elsevier. - 0957-4158 .- 1873-4006. ; 9:7, s. 881-892
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Tidskriftsartikel (refereegranskat)abstract
- An increase in functionality of semi-autonomous vehicles (SAV) through the implementation of intelligent distributed control and smart sensing techniques is presented. In combination with a modular design approach, this facilitates system modification and improvement, combined with faster customisation of the platform. A distributed and reactive behavioural control architecture is used to realise local autonomous navigation capabilities; improved operator interaction; self protection and safer operation. A virtual engineering environment based on a computer-aided-graphics platform is used (1) for modelling the vehicle and the environment in which it can operate; (2) developing pre-emptive learning and training of responses/behaviours, and (3) for evaluation of vehicle functionality as part of an integrated materials handling system.
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| 31. |
- Moore, Philip, et al.
(författare)
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Intelligent semi-autonomous vehicles in materials handling
- 1998
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Ingår i: Mechatronics '98. - Oxford : Pergamon Press. - 0080433391 ; , s. 311-316
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Konferensbidrag (refereegranskat)abstract
- An increase in functionality of Semi-Autonomous Vehicles (SAV) through the implementation of intelligent distributed control and smart sensing techniques is presented. In combination with a modular design approach, this facilitates system modification and improvement, combined with faster customisation of the platform. A distributed and reactive behavioural control architecture will be used to realise local autonomous navigation capabilities; improved operator interaction; self protection and safer operation. A virtual engineering environment based on a suitable computer-aided-graphics platform will be used for modelling the vehicle; the environment in which it can operate; and pre-emptive learning and training of responses / behaviours.
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| 32. |
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| 33. |
- Saranen, Juha, et al.
(författare)
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Modelling Stochastic Elements in Transportation System Simulation : Evidence from Four Projects
- 2008
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Ingår i: Fourth International Railway Logistics Seminar. - : Lappeenranta University of Technology. - 9789522146014 ; , s. 53-76
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Konferensbidrag (refereegranskat)abstract
- Discrete event system simulation is often seen as a genuine tool to investigate the performance of transportation systems. The complexity of real-world systems often prevents us from accurately describing these by a mathematical model that can be evaluated analytically, thus, simulation is often the only realistic alternative. Another advantage of the simulation is the ability to include statistical analysis for different simulation scenarios.In this paper we discuss the main problems concerning the modelling of transportation systems. Well-known approaches of incorporating uncertainty into models include trace driven simulations and sampling directly from gathered data (this latter could also be presented by a fitting statistical distribution). Another aspect to be taken into account is the economics of simulation modelling; a more detailed model requires additional building time, and proper treatment of stochastic models requires statistical analysis, which again usually implies several simulation runs. From this outset the following question arises: Should stochastic behaviour be included in transportation simulation models in the first place at all?We present real case examples including evaluation of a railway transportation concept, capacity analysis of an automatic guided vehicle system, CBA of a railway network investment and evaluation of different multipurpose railway wagons, where stochastic behaviour is dealt with in different ways. Based on the cases we make an initial attempt to formulate framework for deciding how to include stochastic behaviour in the simulation model. We stress that the metrics used to evaluate system performance should be included in the framework. For further research topics we suggest formulating explicit guidelines to deal with stochastics to increase the efficiency of model building.
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| 34. |
- Saranen, Juha, et al.
(författare)
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Stochastic Elements in Transportation System Simulation - Unnecessary?
- 2009
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Ingår i: IFAC Proceedings Volumes. - : Elsevier. - 1474-6670. ; 42:4, s. 1655-1660
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Tidskriftsartikel (refereegranskat)abstract
- Discrete event system simulation is often seen as a genuine tool to investigate the performance of transportation systems. The complexity of real-world systems often prevents us from accurately describing these by a mathematical model that can be evaluated analytically, thus, simulation is often the only realistic alternative. Another advantage of the simulation is the ability to include statistical analysis for different simulation scenarios.Well-known approaches of incorporating uncertainty into models include trace driven simulations and sampling directly from gathered data. Another aspect to be taken into account is the economics of simulation modelling; a more detailed model requires additional building time, and proper treatment of stochastic models requires statistical analysis, which again usually implies several simulation runs. From this outset the following question arises: Should stochastic behaviour be included in transportation simulation models in the first place?We present real case examples including evaluation of the internal logistics of a beverage manufacturer, capacity analysis of an automatic guided vehicle system, cost benefit analysis (CBA) of a railway network investment and evaluation of different multipurpose railway wagons, where stochastic behaviour is dealt with in different ways. Based on the cases we make an initial attempt to formulate framework for deciding how to include stochastic behaviour in the simulation model. For further research topics we suggest formulating explicit guidelines to deal with stochastics to increase the efficiency of model building.
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| 35. |
- Ujvari, Sandor, et al.
(författare)
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Advanced manufacturing simulation : Minor system details can be major issues in the real world
- 2006
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Ingår i: Industrial management & data systems. - : Emerald Group Publishing Limited. - 0263-5577 .- 1758-5783. ; 106:8, s. 1166-1186
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Tidskriftsartikel (refereegranskat)abstract
- Purpose – This paper aims to highlight the complex nature of automated guided vehicle (AGV) simulation model building, and especially how system modelling details affect the end results. This is an important issue in all of the transportation simulation systems, since they are service-based by their nature, and additional inefficiencies create unanticipated performance downgrading.Design/methodology/approach – This paper uses a simulation approach, and simulated systems are based on a real-life case study and on well accepted hypothetical simulation example.Findings – Simulation system boundaries are often neglected in the model building, and especially interface to inbound (and possibly outbound) material flow should be considered carefully; based on these research results, AGV investments are seen in an entirely different light, as system boundary is enlarged to contain more realistically interacting elements. Similar system boundary issues were found from the case study: interface with overhead gantry did not provide near optimal performance. The case study also revealed that high speed of AGVs is not necessarily worth additional investment; constraints exist in safety, acceleration and ability to turn in corners.Research limitations/implications – The findings are based on the simulation work and, to see the real implications, real-life implementations on policy level are needed.Practical implications – Results of this research provide more insights for manufacturing unit investments, and especially in the scope of automated transportation system use. Also changes in manufacturing flow management issues, after investing in, for example, AGV systems, are different from in less-automated manufacturing units.Originality/value – This research work provides more insights to simulation research work, especially from the perspective of transportation systems. Also implications arising from case study are unique as being compared to previous research in the field.
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| 36. |
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| 37. |
- Ujvari, Sandor, et al.
(författare)
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Semi-autonomous vehicles with routing flexibility : functionality and application areas
- 2009
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Ingår i: International Journal of Services and Operations Management. - : InderScience Publishers. - 1744-2370. ; 5:4, s. 444-462
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Tidskriftsartikel (refereegranskat)abstract
- Automated Guided Vehicle (AGV) systems are standard automated items in production and warehousing today. However, studies have rarely examined a more advanced form of AGVs called Semi-Autonomous Vehicles (SAVs), which have a higher sophistication of task completion and routing flexibility. This research presents SAVs in an industrial development case study. Using simulation, the route-keeping ability of SAVs with two types of guidance techniques is being studied. The results show that dual-navigation SAVs can provide the needed flexibility for routing. Using wire guidance and dead reckoning, both very well-established techniques, the SAVs' performance is, within certain limits, quite comparable to the AGVs with more advanced and expensive navigation techniques.
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| 38. |
- Ujvari, Sandor, 1972-, et al.
(författare)
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Simulation and emulation of sensor systems for intelligent vehicles
- 1998
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Ingår i: Mechatronics '98. - : Pergamon Press. - 0080433391 ; , s. 385-390
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Konferensbidrag (refereegranskat)abstract
- Simulation of sensor systems for mobile robots are described in this paper. By simulation of smart sensor systems, the performance of semi-autonomous vehicles / mobile robots can be enhanced. Smart sensor systems used in the field of mobile robotics can utilise adaptive algorithms. e. g. artificial neural nets, fuzzy logic or hybrid variants of these systems. The development, training and evaluation of adaptive algorithms for sensor systems can be done within a virtual environment in which graphical models are built to simulate an intelligent vehicle, its sensors, and its environment. The virtual sensors are validated by comparing the characteristics of the virtual sensors with those of the real devices.
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| 39. |
- Ujvari, Sandor, et al.
(författare)
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Simulation of Automatic Guided Vehicle systems in manufacturing environment : Case: Volvo's Crankshaft Unit in Skovde
- 2008
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Ingår i: International Journal of Manufacturing Technology and Management (IJMTM). - : InderScience Publishers. - 1368-2148 .- 1741-5195. ; 15:1, s. 45-63
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Tidskriftsartikel (refereegranskat)abstract
- Competing in global markets creates pressure for manufacturers to rigidly use automation, and advanced manufacturing techniques to improve manufacturing plant productivity. Among productivity, manufacturers are also interested about other performance dimensions, namely time, flexibility and quality. With the wise use of automation, we could directly improve all of the other indicators, and indirectly quality. In this paper it is shown, how implementation and use of Automatic Guided Vehicles (AGVs) could benefit from the use of manufacturing simulation. AGVs have been available for practical use since the 1970s, but still in the investment and use processes it is rarely seen justified to a high detail, what eventually determines the number of vehicles used in the system. Our paper is able to show with two simulation cases (a hypothetical example and a real case study) that the number of AGVs is very sensitive with respect to production system output. Furthermore, some assumptions that are often made can overly simplify the problem (e.g. no recharging of batteries and constant speed). Therefore, in this paper, we propose that more research should be addressed to the AGV system simulation, and in practice tools for decisions makers should be developed further. Our research also shows that empty travelling and low utilisation is a norm in current AGV systems in order to assure production system functionality, and there is a need and potential for performance improvement here, as well.
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| 40. |
- Ujvari, Sandor, 1972-, et al.
(författare)
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Using simulation for the design of Semi-Autonomous Vehicle systems
- 2001
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Ingår i: IFAC Proceedings Volumes. - : Elsevier. - 1474-6670. - 0080435548 ; 33:20, s. 351-356
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Tidskriftsartikel (refereegranskat)abstract
- The paper describes the development of Semi-Autonomous Vehicles (SAVS) in the context of Automated Guided Vehicle Systems (AGVS). During the design process of a complete material handling AGV-system many variables must be decided. A two-stage simulation approach of discrete event simulation and continuous path simulation, improves development and testing of SAVS, Decisions need to be made e. g. what main navigation sensor to use, how many vehicles are needed for the task. The interrelation of these parameters makes it difficult to find optimum or near-optimum values. Because of this, simulation is a very useful tool to design and evaluate AGV-systems. Copyright (C) 2000 IFAC.
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| 41. |
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| 42. |
- Van Laere, Joeri, et al.
(författare)
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Reflections on fusion systems requirements analysis for maintenance planning
- 2008
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Ingår i: Proceedings of the 2nd Skövde Workshop on Information Fusion planning. - Skövde, Sweden. - 9789163336973 ; , s. 5-8
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Konferensbidrag (refereegranskat)abstract
- Non-defense related industry and public organizations are becoming more and more interested to utilize the power of information fusion applications. The journey from “we have a lot of data from different sources and we would like it to be fused” to well-defined requirements for information fusion applications may however be long and the steps to be taken far from clear. This research in progress paper reflects on the initial steps of a systems requirements analysis in a case study at a maintenance service organization. What questions need to be answered according to existing requirements analysis methods? Where and how can answers be obtained? What problems can arise and how can one handle these? The experiences gathered and discussed can be a basis of the improvement of requirements analysis methods and give a richer understanding of the application of such methods.
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