Asmund Olstad

• Branda, Martin; Haugen, Kjetil K.; Novotný, Jan & Olstad, Asmund (2017). Downstream logistics optimization at EWOS Norway. Mathematics for applications. ISSN 1805-3610. 6(2), p. 127–140. doi: 10.13164/ma.2017.8. Full text in Research Archive Show summary

  The Norwegian company EWOS AS produces fish feed for the salmon farming industry, supplying approximately 300 customers spread along the coast of Norway. The feed is produced at three factory locations and distributed by a fleet of 10 dedicated vessels. The high seasonality of the demand and the large number of customers make the distribution planning a substantial challenge. EWOS handles it by operating a system of mostly fixed routes with decentralized planning at each factory. The distribution can be described as a multi-depot vehicle routing problem with time windows, multiple vehicle usage, inter-depot routes, heterogeneous fleet and a rolling horizon. The paper presents a mathematical model for this problem, which is solved by heuristics and meta heuristics. Based on detailed historical data collected by EWOS during the autumn of 2010, the model has proposed a dynamic set of routes with a significant reduction of travelled distance - close to 30% - and an increase of average vessel fill-rate - from 60% up to 95%. This implies a substantial fuel saving, with a positive environmental impact, and also a potential for downscaling the fleet, with additional considerable cost savings for the company.

• Branda, Martin; Novotný, Jan & Olstad, Asmund (2016). Fixed interval scheduling under uncertainty : a tabu search algorithm for an extended robust coloring formulation. Computers & industrial engineering. ISSN 0360-8352. 93(March), p. 45–54. doi: 10.1016/j.cie.2015.12.021. Show summary

  We propose several formulations of the fixed interval scheduling problem under uncertainty, where the risk is represented by random delays in processing times. We employ various stochastic programming and robust coloring problems to deal with the uncertainty. Our main goal is to introduce equivalent deterministic reformulations of the stochastic programming problems. We show that the minimization of the expected number of overlaps is equivalent to the deterministic robust coloring problem under particular choice of the penalties. Moreover, we extend the robust coloring problem to obtain equivalence with the stochastic programming problem with the schedule reliability objective under multivariate distribution of delays represented by an Archimedean copula. We show that small simulated instances of this problem can be solved to optimality by available software tools and we propose a tabu search algorithm suitable for larger instances. Keywords: Fixed interval scheduling; Uncertainty; Stochastic programming; Robust coloring problem; Archimedean copula; Tabu search.

• Bredström, David; Haugen, Kjetil K.; Olstad, Asmund & Novotný, Jan (2015). A mixed integer linear programming model applied in barge planning for Omya. Operations Research Perspectives. ISSN 2214-7160. 2(December), p. 150–155. doi: 10.1016/j.orp.2015.07.002. Show summary

  This article presents a mathematical model for barge transport planning on the river Rhine, which is part of a decision support system (DSS) recently taken into use by the Swiss company Omya. The system is operated by Omya’s regional office in Cologne, Germany, responsible for distribution planning at the regional distribution center (RDC) in Moerdijk, the Netherlands. The distribution planning is a vital part of supply chain management of Omya’s production of Norwegian high quality calcium carbonate slurry, supplied to European paper manufacturers. The DSS operates within a vendor managed inventory (VMI) setting, where the customer inventories are monitored by Omya, who decides upon the refilling days and quantities delivered by barges. The barge planning problem falls into the category of inventory routing problems (IRP) and is further characterized with multiple products, heterogeneous fleet with availability restrictions (the fleet is owned by third party), vehicle compartments, dependency of barge capacity on water-level, multiple customer visits, bounded customer inventories and rolling planning horizon. There are additional modelling details which had to be considered to make it possible to employ the model in practice at a sufficient level of detail. To the best of our knowledge, we have not been able to find similar models covering all these aspects in barge planning. This article presents the developed mixed-integer programming model and discusses practical experience with its solution. Briefly, it also puts the model into the context of the entire business case of value chain optimization in Omya. Keywords: Process industry; Operations research; Decision support systems; Inventory routing; VMI; Barge planning.

• Olstad, Asmund (2014). Dynamic pricing with capacity constraints and inventory replenishment. Mathematics for applications. ISSN 1805-3610. 3(2), p. 143–166. doi: 10.13164/ma.2014.11. Show summary

  This paper describes a fast algorithm for solving a capacitated dynamic pricing problem where the producer has the ability to store inventory. The pricing problem described is a quadratic programming problem with a structure that can be solved effectively by a dual algorithm. The proposed algorithm gives a solution satisfying the Karush-Kuhn-Tucker conditions. This, combined with the fact that the problem has a convex feasible region with a concave objective function which we want to maximize, implies that the proposed algorithm gives a globally optimal solution. The algorithm is illustrated by numerical examples for both the single-item and the multi-item cases.

• Hrabec, Dušan; Popela, Pavel; Roupec, Jan; Jindra, Petr; Haugen, Kjetil K. & Novotný, Jan [Show all 7 contributors for this article] (2014). Hybrid Algorithm for Wait-and-See Network Design Problem. In Radek, Matoušek (Eds.), MENDEL 2014 : Proceedings of 20th International Conference on Soft Computing. Brno University of Technology. ISSN 978-80-214-4984-8. p. 97–104. Show summary

  The aim of the paper is to introduce a modified hybrid algorithm to solve a wait-and-see reformulation of transportation optimization model with random demand parameters and 0-1 network design variables. Firstly, the deterministic linear transportation model with network design variables is reviewed. Then, uncertain demand parameters are intorduced and modeled by random variables. The following deterministic reformulation is based on the wait-and-see (WS) approach. Finite discrete probability distributions are assumed for all random variables, and hence, the obtained separable scenario-based model can be repeatedly solved as a finite set of mixed integer linear programs (MILPs) by means of integer programming techniques or some heuristics. However, the authors combine a traditional optimization algorithm and a suitable genetic algorithm to obtain a hybrid algorithm that is modified for the WS case. Its implementation and test results illustrated by figures are also discussed in the paper

• Roupec, Jan; Popela, Pavel; Hrabec, Dušan; Novotný, Jan; Olstad, Asmund & Haugen, Kjetil K. (2013). Hybrid Algorithm for Network Design Problem with Uncertain Demands. In Ao, S.I.; Douglas, Craig; Grundfest, Warren S. & Burgstone, Jon (Ed.), Proceedings of The World Congress on Engineering and Computer Science (WCECS) 2013 : Vol I. International Association of Engineers. ISSN 978-988-19252-3-7. p. 554–559. doi: 10.1007/978-3-319-45823-6_61. Show summary

  The purpose of the paper is to present a hybrid algorithm to solve a transportation optimization model with random demand parameters and network design variables. At first, the classical deterministic linear transportation model with network design 0-1 variables is introduced. Then, randomness is considered for demand parameters and modeled by here-and-now approach. The obtained scenario-based model leads to a mixed integer linear program (MILP) that can be solved by common integer programming techniques, see e.g. the branch-and-bound algorithm implemented in the CPLEX solver. Such a program may reach solvability limitations of MIP algorithms for large scale real world data, so a suitable heuristic development is welcome. Therefore, the idea of combination of traditional optimization algorithm and genetic algorithm is discussed and developed. At the end, the results are illustrated and also verified for a small test instance by figures.

• Haugen, Kjetil K.; Lanquepin-Chesnais, Guillaume & Olstad, Asmund (2012). A fast Lagrangian heuristic for large-scale capacitated lot-size problems with restricted cost structures. Kybernetika (Praha). ISSN 0023-5954. 48(2), p. 329–345. Show summary

  In this paper, we demonstrate the computational consequences of making a simple assumption on production cost structures in capacitated lot-size problems. Our results indicate that our cost assumption of increased productivity over time has dramatic effects on the problem sizes which are solvable. Our experiments indicate that problems with more than 1000 products in more than 1000 time periods may be solved within reasonable time. The Lagrangian decomposition algorithm we use does of course not guarantee optimality, but our results indicate surprisingly narrow gaps for such large-scale cases - in most cases significantly outperforming CPLEX. We also demonstrate that general CLSP's can benefit greatly from applying our proposed heuristic.

• Lanquepin-Chesnais, Guillaume; Haugen, Kjetil K. & Olstad, Asmund (2012). Large-scale joint price-inventory decision problems, under resource limitation and a discrete price set. Journal of Mathematical Modelling and Algorithms. ISSN 1570-1166. 11(3), p. 269–280. doi: 10.1007/s10852-012-9184-6. Show summary

  This article addresses a generalization of the capacitated lot-size problem (CLSP) as well as the profit maximization capacitated lot-size problem (PCLSP) considering joint price inventory decisions. This problem maximizes profit over a discrete set of prices subject to resource limitations. We propose a heuristic based on Lagrangian relaxation to resolve the problem, especially aiming for large scale cases. Results of experimentation exhibit the major importance of the capacity constraint. When this one is weak, our heuristic performs particularly well, moreover the numbers of possible prices does not really impact the results. Keywords: Heuristics – Capacitated lot-sizing – Dynamic pricing.

• Hrabec, Dušan; Popela, Pavel; Novotný, Jan; Haugen, Kjetil K. & Olstad, Asmund (2012). The stochastic network design problem with pricing. In Radek, Matoušek (Eds.), MENDEL 2012 : 18th International Conference on Soft Computing. Brno University of Technology. ISSN 978-80-214-4540-6. p. 416–421. Show summary

  The purpose of the paper is to present a step-by-step development of the transportation optimization model with random parameters, network design variables and with pricing. The well-known deterministic linear transportation model with network design 0-1 variables is shortly discussed and it is extended in two separate ways. Firstly, randomness is modeled by so-called here-and-now approach and secondly the deterministic model is enriched with dynamic pricing elements. Then, the combined case is built and the original model is detailed. All cases are illustrated by computations and figures.

• Hrabec, Dušan; Popela, Pavel; Novotný, Jan; Haugen, Kjetil K. & Olstad, Asmund (2012). A note on the newsvendor problem with pricing. In Radek, Matoušek (Eds.), MENDEL 2012 : 18th International Conference on Soft Computing. Brno University of Technology. ISSN 978-80-214-4540-6. p. 410–415. Show summary

  The main purpose of the paper is to present a specific case of dynamic pricing for the newsvendor problem. Firstly, the short overview of a newsvendor problem is given together with references to the selected literature and remarks to its applicability. Then, the dynamic pricing principles are discussed together with references to decision dependent randomness case in stochastic programming. The dynamic pricing problem deals with the determination of selling prices over time for a product whose demand is random and whose supply is fixed. We approach this problem by formulating the newsvendor problem, which is introduced as a single period problem in our case. We focus on the specific features of the demand function assuming decision dependent uniform distribution. We assume that its support size linearly decreases with the increase of the price. Under such assumptions, the model has suitable computational features related to the expectation of the objective function. In addition, possibility to increase the profit by the change of the price may appear. The model formulation allows us to use the MAPLE software for symbolic computations and vizualisation of results. The test results for the selected data set are visualised at the end of the paper.

• Haugen, Kjetil K.; Olstad, Asmund; Bakhrankova, Krystsina & Van Eikenhorst, Erik (2010). The single (and multi) item profit maximizing capacitated lot-size (PCLSP) problem with fixed prices and no set-up. Kybernetika (Praha). ISSN 0023-5954. 46(3), p. 415–422. Show summary

  This paper proposes a specialized LP-algorithm for a sub problem arising in simple Profit maximising Lot-sizing. The setting involves a single (and multi) item production system with negligible set-up costs/times and limited production capacity. The producer faces a monopolistic market with given time-varying linear demand curves.

• Dauzère-Pérès, Stéphane; Nordli, Atle; Olstad, Asmund; Haugen, Kjetil Kåre; Koester, Ulrich & Myrstad, Per Olav [Show all 8 contributors for this article] (2007). Omya Hustadmarmor optimizes its supply chain for delivering calcium carbonate slurry to European paper manufacturers. Interfaces. ISSN 0092-2102. 37(1), p. 39–51. doi: 10.1287/inte.1060.0276. Show summary

  The Norwegian company Omya Hustadmarmor supplies calcium carbonate slurry to European paper manufacturers from a single processing plant, using chemical tank ships of various sizes to transport its products. Transportation costs are lower for large ships than for small ships, but their use increases planning complexity and creates problems in production. In 2001, the company faced overwhelming operational challenges and sought operations-research-based planning support. The CEO, Sturla Steinsvik, contacted More Research Molde, which conducted a project that led to the development of a decision-support system (DSS) for maritime inventory routing. The core of the DSS is an optimization model that is solved through a metaheuristic-based algorithm. The system helps planners to make stronger, faster decisions and has increased predictability and flexibility throughout the supply chain. It has saved production and transportation costs close to US$7 million a year. We project additional direct savings of nearly US$4 million a year as the company adds even larger ships to the fleet as a result of the project. In addition, the company has avoided investments of US$35 million by increasing capacity utilization. Finally, the project has had a positive environmental effect by reducing overall oil consumption by more than 10 percent

• Haugen, Kjetil Kåre; Olstad, Asmund & Pettersen, Bård Inge (2007). Solving large-scale profit maximization capacitated lot-size problems by heuristic methods. Journal of Mathematical Modelling and Algorithms. ISSN 1570-1166. 6(1), p. 135–149. doi: 10.1007/s10852-006-9053-2. Show summary

  This paper introduces a simple heuristic for a quadratic programming sub-problem within a Lagrangean relaxation heuristic for a dynamic pricing and lot-size problem. This simple heuristic is demonstrated to work well on both "standard problem instances" from the CLSP-literature, as well as on very large-scale cases. Additionally, we introduce price constraints within the framework of dynamic pricing, discuss their relevance in a real world market modelling, and demonstrate their applicability within this algorithmic framework.

• Haugen, Kjetil Kåre; Olstad, Asmund & Pettersen, Bård Inge (2007). The profit maximizing capacitated lot-size (PCLSP) problem. European Journal of Operational Research. ISSN 0377-2217. 176(1), p. 165–176. doi: 10.1016/j.ejor.2005.08.001. Show summary

  This paper extends the results for capacitated lot-sizing research to include pricing. Based on a few examples, the new version appears to by much easier to solve computationally. The paper, by including price, can modify demand as well as production schedule. Due to model assumptions (form of demand) a feasible solution can be found easily, unlike CLSP.

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• Haugen, Kjetil K.; Solberg, Harry Arne; Sætre, Irene Lange; Kringstad, Morten; Gammelsæter, Hallgeir & Vik, Erlend [Show all 18 contributors for this article] (2022). Fra toppen av Haugen : historien gjentar seg for tabelltipping-kongen. Panorama : nettavis for Høgskolen i Molde.
• Haugen, Kjetil K.; Solberg, Harry Arne; Sætre, Irene Lange; Loktu, Morten; Guvåg, Bjørn & Owren, Brynjulf [Show all 17 contributors for this article] (2022). Fra toppen av Haugen : årets vinner er fra NTNU. Panorama : nettavis for Høgskolen i Molde.
• Haugen, Kjetil K.; Hauge, Olav; Kringstad, Morten & Olstad, Asmund (2019). Fra toppen av Haugen : jævla Ålesund. Panorama : nettavis for Høgskolen i Molde.
• Popela, Pavel; Novotný, Jan; Roupec, Jan; Hrabec, Dušan & Olstad, Asmund (2014). Two-stage stochastic programming for engineering problems. Engineering Mechanics. ISSN 1802-1484. 21(5), p. 335–353. Show summary

  The purpose of the paper is to present existing and discuss modified optimization models and solution techniques which are suitable for engineering decision-making problems containing random elements with emphasis on two decision stages. The developed approach is called two-stage stochastic programming and the paper links motivation, applicability, theoretical remarks, transformations, input data generation techniques, and selected decomposition algorithms for generalized class of engineering problems. The considered techniques have been found applicable by the experience of the authors in various areas of engineering problems. They have been applied to engineering design problems involving constraints based on differential equations to achieve reliable solutions. They have served for technological process control e.g. in melting, casting, and sustainable energy production. They have been used for industrial production technologies involving related logistics, as e.g. fixed interval scheduling under uncertainty. The paper originally introduces several recent improvements in the linked parts and it focuses on the unified two-stage stochastic programming approach to engineering problems in general. It utilizes authentic experience and ideas obtained in certain application areas and advises their fruitful utilization for other cases. The paper follows the paper published in 2010 which deals with the applicability of static stochastic programs to engineering design problems. Therefore, it refers to the basic concepts and notation introduced there and reviews only the principal ideas in the beginning. Then, it focuses on motivation of recourse concepts and two decision stages from engineering point of view. The principal models are introduced and selected theoretical features are reviewed. They are also accompanied by the discussion about difficulties caused by real-world cases. Scenario-based approach is detailed as the important one for the solution of engineering problems, discussion in data input generation is added together with model transformation remarks. Robust algorithms suitable for engineering problems involving nonlinearities and integer variables are selected and scenario-based decomposition is preferred. An original experience with using heuristics is shared. Several postprocessing remarks are added at the end of the paper, which is followed by an extensive literature review. Keywords : two-stage stochastic programming, modelling, scenarios, decomposition, algorithms

• Hrabec, Dušan; Popela, Pavel; Roupec, Jan; Jindra, Petr; Haugen, Kjetil K. & Novotný, Jan [Show all 7 contributors for this article] (2014). Hybrid algorithm for wait-and-see network design problem.
• Hrabec, Dušan; Popela, Pavel; Novotný, Jan; Haugen, Kjetil K. & Olstad, Asmund (2012). The stochastic network design problem with pricing.
• Hrabec, Dušan; Popela, Pavel; Novotný, Jan; Haugen, Kjetil K. & Olstad, Asmund (2012). A note on newsvendor problem with pricing.
• Løkketangen, Arne; Haugen, Kjetil Kåre; Lanquepin, Guillaume & Olstad, Asmund (2009). Using a set of fixed prices when solving Profit Maximization Capacitated Lot-Size Problems (PCLSP). Show summary

  The Capacitated Lot-Size Problem, CLSP, is central in production planning research, and a lot of publications on this problem exists (see e.g. [2]). Many formulations, variants and extensions exist for this problem. We have previously looked at this problem using a profit maximization formulation instead of the customary cost minimization (see [4]). This work has later been extended by solving larger instances, using heuristics, and adding price limits (see [5]). The reasoning behind these extensions is that instead of having a fixed demand, the actual demand can be influenced by changing the prices for these commodities. This again influences the required capacity. As noted in our previous work, we assume a monopolistic situation. This is somewhat unrealistic, but we argue that our work might be transferable to more realistic (e.g. oligopolistic/gametheoretic) market environments. The main point is that demand can be affected, not necessarily the complexity of the demand description. In [3] the authors argue that there are three factors driving the trend towards demand based management: (1) increased availability of demand data, (2) it is becoming increasingly easier to change the prices, and (3) the increased availability of decision support tools. They claim that dynamic pricing will migrate from the hotel and airline industry to retail and other industries where sellers are able to store inventory. Lee [9] writes: What will be the next competitive battleground in the 21st century? It will be managing the demand for the total value maximization of the enterprize and value chains - Demand- Based management. In our previous work the prices where continuous, and could take on any value within its bounds. This is a somewhat unrealistic condition. It is much more common for most commodities that the prices are discretized, with a certain distance between the price levels. We will look at this case of a fixed set of prices per commodity. Of interest are the consequences of the discretization algorithmically and how the computational results are affected. We will also look at the consequences of the various pricing policies that can be applied. This is work-in-progress. Novel heuristics, based on Tabu Search (see [6]), but also integrating Cplex [1], and classical heuristics based on the Wagner-Whitin [10] and Thomas [8] algorithms as subproblem solvers will be developed. Extensive computational results will be reported, based on (modified) instances from Lotsize-lib [7] and on instances previously published by the authors.

• Haugen, Kjetil Kåre; Olstad, Asmund; Bakhrankova, Krystsina & Van Eikenhorst, Erik (2009). The Single Item profit maximizing capacitated lot-size (PCLSP) problem with fixed prices and no set-up. Show summary

  Even though modern LP-servers (and computers) are extremely efficient, fast specialized sub-problem solvers may be of interest. Here we focus on an LP arising as a typical sub-problem in Dynamic Pricing problems. We demonstrate the algorithmic development and conclude with some simple speed tests, demonstrating computational efficiency.

• Olstad, Asmund (2008). Innkjøpsstyring ved lange ledetider.
• Olstad, Asmund (2007). Integrert mellom markedsføring og logistikk : Demand Based Management (DBM). Show summary

  Tradisjonelt har markedsføring og logistikk blitt sett på som «to separate» styringsfunksjoner hvor markedsføringsfunksjonen fastsetter priser og markedsføringstiltak med sikte på å maksimere salgsinntekter (eller salgsvolum), mens logistikkfunksjonen minimerer kostnader gitt etterspørsel (eller prognoser over denne).En slik styringsstruktur vil åpenbart ikke være noen garanti for å ivareta bedriftens overordnede mål; maksimering av profitt/overskudd.DBM fokuserer på integrasjon mellom markedsføring og logistikk der prisingsprinsippene innen moderne luftfart (dynamisk prising) er overført til tradisjonell industri- og (annen) serviceproduksjon og hvor målet er maksimering av profitt. I nylig utarbeidet rapport av Mc kinsey blir DBM og prisingsstrategier hevdet å representere det beste virkemiddelet for overskuddsforbedring i industrielle virksomheter. Dell og Amazone.com representerer bedrifter som har tatt i bruk DBM med hell.

• Olstad, Asmund; Haugen, Kjetil Kåre; Nordli, Atle; Dauzère-Peres, Stéphane; Reistad, Alf & Myrstad, Per Olav [Show all 7 contributors for this article] (2006). Omya Hustadmarmor : optimizing the supply chain of calcium carbonate slurry to the European paper making industry. Show summary

  Omya Hustadmarmor supplies calcium carbonate slurry to European paper manufacturers. The products are transported out from a single processing plant. In 2001, the company was facing a situation with overwhelming operational challenges and decided to look for OR-based planning support. Møre Research Molde conducted a project that led to the development of a Decision Support System for maritime inventory routing, providing planners with the necessary support to make stronger and faster decisions. This has increased both predictability and flexibility throughout the supply chain, resulting in direct savings in production and transportation costs of close to $7US million a year. Also projected are additional direct savings of nearly $4 million a year, since even larger ships can be added to the fleet. Investments of $35 million have been avoided due to increased capacity utilization.

• Nygreen, Bjørn; Haugen, Kjetil Kåre & Olstad, Asmund (1999). Nonlinear capacitated lot sizing.
• Haugen, Kjetil Kåre & Olstad, Asmund (1997). Fleksnes tar nye utfordringer. Romsdals Budstikke.. ISSN 0806-5160. 155(26.09.1997), p. 15–15.
• Bjarnar, Ove & Olstad, Asmund (1997). Kompetanse gir næringsutvikling. Romsdals Budstikke.. ISSN 0806-5160. 155.
• Haugen, Kjetil Kåre; Nygreen, Bjørn & Olstad, Asmund (1997). Solving a quadratic program arising in capacitated lot sizing.
• Haugen, Kjetil K.; Nygreen, Bjørn & Olstad, Asmund (1997). Solving a quadratic program arising in capacitated lot sizing. In Carøe, Claus C. & Pisinger, David (Ed.), NOAS '97 : Nordic operations Recearch Conference : University of Copenhagen, Denmark, August 15 - 16 1997. Danish Operations Research Society (DORS).
• Hervik, Arild; Olstad, Asmund & Bråthen, Svein (1987). Om markedet, takstsystemet og samfunnsøkonomisk riktig prising i ferjesektoren.
• Bjarnar, Ove; Haugen, Kjetil Kåre; Hervik, Arild; Olstad, Asmund; Oterhals, Oddmund & Risnes, Martin (2010). Nyskaping og næringsutvikling i Møre og Romsdal : sluttrapport. Møreforsking Molde AS. ISSN 0803-9259. Show summary

  GMS prosjektet "Nyskaping og næringsutvikling i Møre og Romsdal" har hatt sitt faglige fokus rettet mot den videre utvikling av verdiskapingspotensialet i den maritime næringsklyngen i regionen. Arbeidet har vært nær knyttet opp til et langvarig arbeid i fagmiljøet med næringsøkonomiske studier av den maritime klyngen. Utsiktene for den videre utvikling i den maritime næringen etter den globale finanskrisen, har vært et dominerende tema i prosjektet den siste tiden. Arbeidet innen dette prosjektet har gitt anledning til å inkludere sentrale tema som innovasjon og kunnskapsdeling i globale og regionale næringsklynger. Det er i prosjektet utviklet en modell for logistikkplanlegging knyttet til produksjon på ulike geografiske steder og ved bruk av ulik type arbeidskraft. Modellen gir et grunnlag for å drøfte spørsmål knyttet til outsourcing ved produksjon i lavkostland. Det har videre vært arbeidet med å utvikle et beslutningsstøtteverktøy for operasjonell planlegging i prosjektorientert produksjon. Prosjektet har vært gjennomført i tett dialog mellom referansegruppen og prosjektgruppen. Referansegruppen har ut fra sin brede erfaring fra næringen, på en meget konstruktiv måte bidratt til å fange opp sentrale forskningsmessige tema som er av stor praktisk relevans for næringen. Vi ser denne arbeidsformen som et eksempel på et vellykket samarbeid mellom bedrift/næring og forskningsmiljø. Samlet har prosjektet på en meget god måte bidratt til å bygge ut og styrke den samlede forskningskompetansen ved Høgskolen i Molde og Møreforsking Molde AS, på områder av potensiell stor betydning for den videre utvikling i den maritime næringen. Flere av de forskningsmessige temaene som er tatt opp i prosjektet er under videre utvikling gjennom andre prosjekter ved Høgskolen i Molde/Møreforsking. Tilbakemeldingene fra bedriftsrepresentanter er at resultatene fra prosjektet blir oppfattet som relevante og nyttige for å forstå og takle de utfordringene en står ovenfor og gjennom dette bidra til en videre utvikling av verdiskapingspotensialet for den maritime næringsklyngen i Møre og Romsdal.

• Olstad, Asmund (2010). Web-basert IT-system for beslutningsstøtte og kommunikasjon i operasjonell planlegging av prosjektorientert produksjon. Høgskolen i Molde. ISSN 978-82-7962-125-6.
• Olstad, Asmund (2006). Dynamic pricing and lot-sizing within manufacturing. Norges handelshøyskole, Bergen. ISSN 8240501613.
• Hervik, Arild; Haugen, Kjetil Kåre; Olstad, Asmund; Jörnsten, Kurt & Bræin, Lasse (1999). Midtveis evaluering av logitransprogrammet i Norges forskningsråd. Møreforsking, Molde. ISSN 0803-9259.
• Haugen, Kjetil Kåre; Løkketangen, Arne; Woodruff, David L.; Nygreen, Bjørn & Olstad, Asmund (1998). Profittmaksimerende produksjons- og lagerstyringsmodeller under usikkerhet. Møreforsking Molde. ISSN 0803-9259. Show summary

  Denne rapporten omhandler ulike algoritmiske løsninger på det problemkompleks som litt løselig kan karakteriseres som profittmaksimerende produksjons- og lagerstyringsmodeller under usikkerhet. Hovedresultatene fra arbeidet kan oppsummeres i form av to foreslåtte algoritmer. Den første algoritmen (heurestikk) søker å løse et klassisk en-produkts "Lot-size" problem med usikker etterspørsel. Det metodiske grep som anvendes er den såkalte "Progressive Hedging" algoritmen. Den rapporterte heurestikk gir svært raskt svært gode løsninger sammenliknet med alternativ programvare. Eksempelvis rapporterer vi en hastighetsforbedring i størrelsesorden 1000 ganger for rimelig store case. Det andre hovedresultatet er konsentrert rundt utvikling av en algoritme for løsning av "CLSP"-problemet med profittmaksimering. Dette problemet - uten profittmaksimering - er en klassiker i "Lot-size"-litteraturen, og en hovedhypotese i denne delen av prosjektet har vært: a) Introduksjon av profittmaksimering gir mulighet for raskere løsning enn i kostnadsminimeringstilfellet. b) Introduksjon av profittmaksimering gir bedre og mer realistiske modeller for næringslivet. Vår foreslåtte algoritme gir bekreftende indikasjon på hypotesen i a). Algoritmen er riktignok ikke testet ut i full bredde, prosjektrammen ga ikke mulighet for dette, men all numerisk testing så langt tyder på at basishypotesen er rimelig. Det har ikke vært en klar målsetting å foreta konkret empirisk vurdering av hypotese b), men samtaler med en rekke aktører i næringsliv og forvaltning indikerer at behovet for denne typen modellering er stort.

• Olstad, Asmund & Sandum, Kjell Tore (1994). EDB-basert beslutningsstøttesystem for serie- og innkjøpsplanlegging utviklet for T. Skretting AS : systembeskrivelse og brukerveiledning. Møreforsking Molde. ISSN 0803-9259.
• Halskau, Øyvind; Løkketangen, Arne & Olstad, Asmund (1994). Tettere koplinger i verdikjeder : metodeorientert problemløsning for noen utvalgte bedrifter. Møreforsking Molde. ISSN 82-7692-035-7.
• Olstad, Asmund & Bråthen, Svein (1987). Prognoser for flytrafikk og kapasitetsbehov i Widerøes Flyveselskap i 1990-årene. Møreforsking Molde. ISSN 0803-9259. Show summary

  Formålet med rapporten "Prognoser for flytrafikk og kapasitetsbehov i Widerøes Flyveselskap i 1990-årene" er å forutsi utviklingen i paxkm. inn i 1990-årene for totaltrafikken og de fire største ruteområdene. Vi har tatt utgangspunkt i to metoder: 1. En ren framskrivning av trafikkveksten fra 1975-86 og 1983-86. Starttidspunkt velges ut fra hvilken tidsperiode en anser som mest representativ for framtidig utvikling. 2. En analysemetode basert på på en lineær regresjonsmodell (minste kvadraters metode). Vi har benyttet utviklingen i tilbudt kapasitet, realtakst samt en trendfaktor for å forklare og gi anslag på trafikkutviklingen inn i 1990-årene. Trendfaktoren løper fra 1 (01.1975) til 144 (12.1986), og fanger opp utviklingen i bruttonasjonalprodukt, befolkningsvekst, personlig inntekt etc.). Vi har i det videre prognosearbeid valgt å benytte analyseresultatene fra metode 2. En regresjonsmodell kan i denne sammenheng beskrives som en metode til å forutsi trafikkvekst i årene som kommer på bakgrunn av historiske data. Vi har valgt å benytte setekm. og paxkm. fra 1975-86 for hvert ruteområde og hver måned. I tillegg har vi fra samme tidsrom realtakstutvikling, trendfaktor, innføring av DHC-7 og innføring av minipris som datagrunnlag. Analysen viser hvordan hver enkelt faktor (eks. økning i tilbudt kapasitet) vil kunne influere på trafikkveksten inn i 1990-årene. Vi har i samsvar med selskapets egne erfaringer slått fast at økning i antall tilbudte flyseter i seg selv skaper økt trafikk. I analysen har vi derfor tatt med hvordan endringer i antall tilbudte setekm. erfaringsmessig influerer på trafikkveksten. I tillegg har vi sett på innføring av DHC-7 på de ulike ruteområder for å studere hvorvidt større og mer komfortable fly har generert ny trafikk. Regresjonsmetoden anvendt på en forsvarlig måte krever omfattende innsikt i statistisk metode. Innflytelsen fra setekm. (tilbudt kapasitet), takstutviklingen og trendfaktoren på trafikkveksten mener vi er rimelig godt statistisk bestemt. Medellens evne til å forklare hele utviklingsforløpet (forklaringskraften)er tilfredsstillende. I tabell 5.1 - 5.5 har vi oppsummert resultatene fra analysen. Her er illustrert veksten i trafikken i de 4 største ruteområdene og totalt. Det er vist 3 ulike vekstbaner, avhengig av i hvilken grad man tilgodeser ny trafikk med økt kapasitet.

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