News from IØT

Vegar Lein Ausrød successful defence of PhD thesis

«Commercialization of renewable energy in rural India: Entrepreneurial activities for building a profitable venture at the base of the pyramid»

Supervisor: Professor Roger Sørheim

Vegar Lein Ausrød successful defence of PhD thesis

«Commercialization of renewable energy in rural India: Entrepreneurial activities for building a profitable venture at the base of the pyramid»

Supervisor: Professor Roger Sørheim

We congratulate Vegar Lein Ausrød with successful defense of his PhD, December 14th 2016.

The title of the thesis is

«Commercialization of renewable energy in rural India: Entrepreneurial activities for building a profitable venture at the base of the pyramid»

The Faculty of Social Sciences and Technology Management has appointed the following committee to evaluate the thesis:

  • Associate Professor Diamanto Politis, Lund University, Sweden
  • Associate Professor Steffen Korsgaard, Aarhus University, Denmark
  • Professor Øystein Moen, NTNU

Professor Øystein Moen at the Department of Industrial Economics and Technology Management, NTNU, has administered the committee’s work.

The trial lecture was on on the following topic

«The business model concept: past, present and future»

The candidate’s main supervisor has been Professor Roger Sørheim, NTNU. Co-supervisor has been Professor Helle Neergaard, Aarhus University.

Summary of the thesis

This thesis seeks to achieve two objectives. First it aims to understand how entrepreneurs are able to provide products and services to the base of the pyramid (BoP) while simultaneously generate profits. Thus, the overall research question of the thesis is: how do commercially driven entrepreneurs build a firm in a BoP context? The answer to this unfolds in the cover of this thesis by combining the theoretical contributions found in each of the four articles. Second, the thesis seeks to contribute to existing theories and literature often applied to explain entrepreneurial actions. This is done through the four articles.

Article 1 seeks to contribute to resource-based theory (RBT) as it says little about resource management and its interplay with context. The findings suggest that entrepreneurs at the BoP can apply dispersed spatial and business contexts to structure and bundle resources.

Article 2 contributes to resource management and resource mobilization. This article argues that the inability of presumed strategic resources to become intricately embedded in the local context is the reason for their failure. Conversely, the ability of presumed ordinary and weak resources to become intricately embedded in the local context is the reason for their success.

Article 3 unfolds the business model design dilemma of adapting to or shaping the context in which they are deployed. Specifically designed interim business models in which each model design either facilitates an “adaptation to” process or a “shaping of” process.

Article 4 focuses on the modes of growth. This article suggests that growth modes should be studied in combination with the business model; that not only organic growth takes place in new ventures; and it offers a perspective to understand erratic growth patterns in a new venture.

Because creating profitable firms targeting the BoP is an under-explored and complex phenomenon, a qualitative research design has been adopted. All research questions are answered through a single case study of Husk Power Systems (HPS), the world-leading mini-utility firm providing rural electricity based on renewable energy sources for the BoP segment.

 

Sammendrag av avhandlingen

Denne avhandlingen har to hovedformål. Den bidrar til en forståelse av hvordan entreprenører kan tilby produkter og tjenester til verdens fattigste – også omtalt som “the base of the pyramid” (BoP) – under kommersielle betingelser. Det overordnede forskningsspørsmålet er: Hvordan bygger kommersielt motiverte entreprenører et selskap i en BoP kontekst? Ved å kombinere de teoretiske bidragene i hver artikkel, gis svaret på dette spørsmålet i kappa av avhandlingen. Det andre formålet med avhandlingen er å bidra til eksisterende teorier og litteratur som ofte blir brukt til å forklare entreprenørielle handlinger. Dette gjøres i de fire artiklene.

Artikkel 1 bidrar til ressursbasert teori (RBT) som kun i begrenset omfang behandler ledelse av ressurser i samspill med kontekst. Funnene viser at BoP-entreprenører kan ta i bruk ulike kontekster for å strukturere og kombinere ressurser.            

Artikkel 2 bidrar til teorier for ressursledelse og –mobilisering. Det argumenteres for at antatt strategiske ressurser feiler på grunn av deres manglende evne til å integreres i konteksten. Likeledes kan antatt ordinære eller svake ressurser bli verdifulle nettopp på grunn av deres integrasjonsevne.

Artikkel 3 viser at det oppstår et dilemma når en forretningsmodell skal utvikles: Skal forretningsmodellen tilpasses kontekst eller skal den forsøke å endre konteksten den skal implementeres i. Det argumenteres for at midlertidige tilpassede forretningsmodeller kan støtte en ”tilpasning til” eller en ”endring av” kontekst.

Artikkel 4 tar for seg vekst. Artikkelen hevder at ulike vekstformer bør sees i sammenheng med valg av forretningsmodell, og at vekst i nye selskaper ikke kan begrenses til organisk vekst. Den forklarer også hvordan ulineære vekstmønstre i nye selskaper kan forstås.

Etablering av lønnsomme selskaper rettet mot BoP har i liten grad blitt studert, og temaet er komplekst. En kvalitativ tilnærming er derfor velegnet for forskningsformålet, og et slikt design har blitt brukt i dette arbeidet. Alle forskningsspørsmålene har blitt besvart gjennom et enkelt case studium av Husk Power Systems (HPS). HPS er verdensledende innenfor minielektrisitetsnettverk basert på fornybar energi i BoP.


Per Arne Vidar Sjønøst

Godfrey Mugurusi successful defence of PhD thesis

«Offshoring & the aftermath: Implications for the management of the purchasing and supply function»

Supervisor: Professor Luitzen de Boer

Godfrey Mugurusi successful defence of PhD thesis

«Offshoring & the aftermath: Implications for the management of the purchasing and supply function»

Supervisor: Professor Luitzen de Boer

We congratulate Godfrey Mugurusi with successful defense of his PhD, August 24th 2016.

The title of the thesis is:

«Offshoring & the aftermath: Implications for the management of the purchasing and supply function»

The Faculty of Social Sciences and Technology Management has appointed the following committee to evaluate the thesis:

  • Professor Veli Matti Virolainen, Lappeenranta University of Technology
  • Associate Professor Kajsa Hulthén, Chalmers University of Technology
  • Associate Professor Tim Kristian Andreas Torvatn, NTNU
     

Associate Professor Tim Kristian Andreas Torvatn at the Department of Industrial Economics and Technology Management, NTNU, has administered the committee’s work.

The trial lecture was on on the following topic:

«Theory and practice of offshoring – an overview in time from historical roots to current trends»

The candidate’s main supervisor has been Professor Luitzen de Boer, NTNU. Co-supervisor has been Professor Arild Aspelund, NTNU.

 

Summary of the thesis

This thesis investigates the broad question: what happens to the purchasing and supply management (PSM) function when the firm engages in production offshoring?

This question emerges from varied and contemporary debates on the implications of the offshoring strategy on the firm’s value chain, the re-configuration of its capabilities in new environments, and the changes in firm level competences as a result of emerging complexity.  The thesis particularly focuses on the PSM function, which despite its known strategic importance to firm performance, has not received a lot of attention on how it deals with the challenges that emerge from offshoring. Yet clearly, and as I empirically show, the events in the disintegration and geographical dispersal of firm activities for cost and other related reasons, undermines PSM function’s existing routines, effectiveness and performance.

In general, the research adopts a qualitative approach in which the case study methodology is used mainly to answer and build on the conceptual, theoretical and empirical questions raised in the earlier parts of the research. The contributions and findings are reported in 4 papers – 3 of these are published journal articles and 1 article is an unpublished research paper.

The article 1 examines the state of the research on the production offshoring phenomenon and subsequently investigates, how, following the disintegration of the firm, the aspect of reintegration of disaggregated and dispersed activities is considered in production offshoring research. First the article shows that production offshoring research is largely conceptual, and second, it shows that reintegration of dispersed activities is seen as both an issue of intra-firm governance, and also that of building on existing linkages in production network activities.  

The article 2 contributes to the theoretical understanding of the production firm as it implements the offshoring strategy, suggesting that the existing piece-meal theoretical explanations of the offshoring firm’s behavior ignore the systemic changes these firms make in order to remain viable.  The article 3 builds on the existing offshoring evolutionary models to explain the specific changes that occur in the purchasing and supply organization as a result of offshoring. The findings suggest that offshoring is not only PSMs key change lever, but also presents momentum for reorganizing in the PSM function.

Finally article 4 examines the level of coordination of the PSM function’s activities in the face of offshoring. The article suggests that the current view of coordination in PSM which addresses mainly the interface between activities and purchasing’s personnel is inherently flawed. It sidelines the role of coordination of information exchanges among purchasing process actors as a fundamental enabler of PSM activities coordination. 

In conclusion, the thesis demonstrates that offshoring strategies have significant implications for organizations that pursue them. Yet to PSM, these implications also present significant opportunities for the reinvention of PSM’s role in the firm thus assuring better purchasing performance, and ensuring that the firm remains viable in the long term.

Øyvind Bjørgum successful defence of PhD thesis

«New firms developing novel technology in a complex emerging industry: The road towards commercialization of renewable marine energy technologies»

Supervisor: Professor Øystein Moen

Øyvind Bjørgum successful defence of PhD thesis

«New firms developing novel technology in a complex emerging industry: The road towards commercialization of renewable marine energy technologies»

Supervisor: Professor Øystein Moen

We congratulate Øyvind Bjørgum with successful defense of his PhD, June 9th 2016.

The candidate, supervisor and committee. Photo: IØT

The title of his thesis is:
«New firms developing novel technology in a complex emerging industry: The road towards commercialization of renewable marine energy technologies»

The Faculty of Social Sciences and Technology Management has appointed the following committee to evaluate the thesis:
Professor Gary Knight, Willamette University, USA
Professor Niina Nummela, University of Turku, Finland
Associate Professor Lise Aaboen, NTNU

Associate Professor Lise Aaboen at the Department of Industrial Economics and Technology Management, NTNU, has administered the committee’s work.

The trial lecture was held on the following topic:
«Quantitative research designs for investigating complex emerging industries – Potential contributions to theory building and research»

The candidate’s main supervisor has been Professor Øystein Moen, NTNU. The candidate’s co-supervisor has been Professor Tage Koed Madsen, NTNU/University of Southern Denmark.

 

Summary of the thesis

This thesis addresses new technology firms in a complex emerging industry. New firms are typically important participants in emerging industries because of their introduction of new innovative ideas and technologies. However, in addition to their limited resources related to funding, technology expertise and network, new firms in emerging industries are also challenged by a limited socio-political legitimacy compared to firms operating within existing industries. This thesis focuses on how firms can overcome these challenges.

The context of the research has been the emerging marine energy industry, which consists of firms developing devices to harness energy from ocean waves and tides. Through multiple-case studies of firms within the industry, four papers addressing different aspects related to technology commercialization have been developed.

Article 1 studies the extent of early internationalization among Norwegian marine energy firms. It shows how firms, through international activities, access resources such as funding and technology competence which help them to further develop their technology towards commercialization.

Article 2 contributes to the understanding of investors’ non-financial involvement in new technology firms in the early stages of an emerging industry, and focuses on the positive contributions of different types of investors such as business angels, venture capitalists and larger corporations.

Article 3 investigates how new technology firms organize their technology development and manufacturing of components in the context of the emerging marine energy industry. The study proposes and discusses three different supply chain configurations.

Article 4 studies how MNCs’ assessment of different uncertainties affects their governance mode when entering an emerging industry. More specifically, if MNCs choose modes giving flexibility (minority investments) or control (internal development or acquisition).

The summary chapter divides the commercialization process in the marine energy industry into three specific technological and financial gaps: 1) ‘From laboratory to scale models’, 2) ‘From scale models to the real world’, and 3) ‘Towards commercialization’. These gaps are increasingly more technologically advanced and capital demanding, and it is discussed how different investors and strategies related to internationalization and supply chain configuration, can help overcome these gaps. Finally, implications for research, managers and policy makers are discussed.

Lars Hellemo successful defence of PhD thesis

«Managing Uncertainty in Design and Operation of Natural Gas Infrastructure»

Supervisor: Professor Asgeir Tomasgard, NTNU

Lars Hellemo successful defence of PhD thesis

«Managing Uncertainty in Design and Operation of Natural Gas Infrastructure»

Supervisor: Professor Asgeir Tomasgard, NTNU

We congratulate Lars Hellemo with successful defense of his PhD, June 6th 2016.

The candidate with committee, Photo: Fotograf Elin Iversen

The title of his thesis is:
«Managing Uncertainty in Design and Operation of Natural Gas Infrastructure»

The Faculty of Social Sciences and Technology Management has appointed the following committee to evaluate the thesis:
Professor Laureano F. Escudero, King Juan Carlos University
Professor Mette Helene Bjørndal, Norwegian School of Economics
Professor Bjørn Nygreen, NTNU

Professor Bjørn Nygreen at the Department of Industrial Economics and Technology Management, NTNU, has administered the committee’s work.

The trial lecture were held on the following topic:
«Equilibrium models for infrastructure planning, theory and practical applications (The applications should not be taken from the Norwegian continental shelf or other gas applications)»

The candidate’s main supervisor has been Professor Asgeir Tomasgard, NTNU.

 

Summary of the thesis

This thesis concerns the management of uncertainty in design and operation of natural gas infrastructure by means of mathematical programming. The export of natural gas is an important industry in Norway. Investments in infrastructure such as subsea pipelines and processing facilities with long lifetime are capital intensive and mandate thorough analysis of future cash flows to assess profitability.

Several crucial parameters are uncertain, such as resources, costs and future prices, and analysis of net present value should consider this uncertainty carefully. The long lifetime with significant short-term uncertainty and variability in addition to long-term uncertainty makes this particularly challenging.

Natural gas is not a homogenous commodity, and different composition of gas from each field makes the management of gas quality an important consideration. Gas quality may be altered through mixing in the transport pipeline network, or in processing facilities. Accounting for pooling in the network with quality constraints introduces computationally expensive non-convex formulations.

The main contributions of the work in this thesis consists of modelling short- and long-term uncertainty for design and operation of natural gas networks in models that combine these demands and introduce multi-horizon stochastic programming.

The pooling problem is addressed by a novel discretization scheme and auxiliary linear programs that will improve solution times in many instances. A generalized global optimization multi-commodity pooling formulation with processing facilities and composite quality constraints is appropriate for analysis in this context.

Traditionally, analysts consider uncertainty as exogenous, i.e. unaffected by the decisions in the model. In this thesis, the work on stochastic programming with endogenous uncertainty is reviewed with an expanded taxonomy, with several novel models with decision-dependent probabilities. This demonstrates how this problem may be addressed through the framework of stochastic programming with recourse.

Tyson John Weaver successful defence of PhD thesis

«STRATEGIC MANAGEMENT OF POWER PRODUCERS: Implementing international renewable power production growth strategies»

Supervisor: Professor Øystein Moen

Tyson John Weaver successful defence of PhD thesis

«STRATEGIC MANAGEMENT OF POWER PRODUCERS: Implementing international renewable power production growth strategies»

Supervisor: Professor Øystein Moen

We congratulate Tyson John Weaver with successful defense of his PhD, April 28th 2016.

The candidate and supervisors, Photo: Fotograf Elin Iversen

The title of his thesis is:
«STRATEGIC MANAGEMENT OF POWER PRODUCERS: Implementing international renewable power production growth strategies»

The Faculty of Social Sciences and Technology Management has appointed the following committee to evaluate the thesis:
Professor Sami Saarenketo, Lappeenranta University of Technology
Associate Professor Per Servais, University of Southern Denmark
Professor Lars Øystein Widding, NTNU

Professor Lars Øystein Widding at the Department of Industrial Economics and Technology Management, NTNU, has administered the committee’s work.

The trial lecture were held on the following topic:
«Internationalization of established firms: motives, market selection processes and the role of institutions»

The candidate’s main supervisor has been Professor Øystein Moen, NTNU. The candidate’s co-supervisor has been Professor Erling Holden, Sogn og Fjordane University College.

 

Summary of the thesis

This thesis investigates internationalization motives and methods for electric power producers. Using international business and strategic management literature streams, it focuses on the business dynamics that are driving or hindering internationalization of these firms. Additional focus is placed on firm characteristics and strategies that embody successful internationalization of the power producer.

The four articles that comprise this thesis use a variety of methods and data, often combining qualitative and quantitative methods with several diverging data sources in mixed method designs.

Article 1 underpinned the financial attractiveness of deploying offshore wind energy in the UK. Two operational projects were selected as cases to utilize five years of empirical data as the foundation for the analysis. Financial viability was subjected to a sensitivity analysis to determine the effects of cost of capital on profitability.

Article 2 investigated firms in the Norwegian power sector by mapping out international investment plans and their motivations and barriers for pursuing such activities.

Article 3 looked more global in orientation, using six case companies to track their development patterns after choosing internationalization pathways. We focused on their chosen market entry modes and roles of management in internationalization processes.

The last article sought to understand how firms assess the potential of foreign markets. After collecting macroeconomic parameters, a model was built to produce a list of the most attractive future markets for hydropower development and operation.

The summary chapter of the thesis concludes with a discussion on 5 key findings: 1) companies are motivated, but face many obstacles; 2) the public ownership model restricts growth potential; 3) returning focus to core business results in less new business development; 4) internationalization provides a financial hedge to the market downturn; and 5) fresh capital and new ownership structures are needed to go abroad. Implications are then derived for theory, managers, and policy.

Anders Gullhav successful defence of PhD thesis

«Optimization-based Resource Allocation in Cloud Computing»

Supervisor: Bjørn Nygreen 

Anders Gullhav successful defence of PhD thesis

«Optimization-based Resource Allocation in Cloud Computing»

Supervisor: Bjørn Nygreen 

We congratulate Anders Nordby Gullhav with a successful defense of his PhD, March 3rd 2016.

The title of the thesis is:

«Optimization-based Resource Allocation in Cloud Computing»

The following committee has evaluated the thesis:

The trial lecture was held on the following topic:

«Matheuristics theory and applications in techno-economic decision making»

The candidate’s main supervisor has been Professor Bjørn Nygreen, NTNU. The candidate’s co-supervisors have been Professor Poul Einar Heegaard, NTNU, and Professor Lars Magnus Hvattum, NTNU/Molde University College.

 

Summary of the thesis

This thesis considers the resource allocation problem of a cloud service provider (SP), which provides at set of services delivered through the software-as-a-service model. The SP owns and operates a private cloud, but in periods of high demand, the SP also relies on infrastructure resources provided by a public cloud in the service provisioning. Even though the market for cloud computing services has been growing and is expected to grow further in the future, low quality of service (QoS) is seen as an important issue to be resolved by the cloud computing industry.

The focused resource allocation problem translates to the problem of allocating appropriate resources to the services of the SP in a cost-efficient manner, and so that the QoS is in accordance with the requirements specified in the service level agreements (SLAs) between the provider and the users. This problem is represented as an optimization problem. However, analytic and simulation-based models are used to describe the relationship between a given allocation or resources to a service and the resulting QoS.

This thesis consists of five research papers, and in short, these papers try to answer the following two interrelated questions: 1) Given a certain resource allocation to a service, does this service satisfy the QoS guarantees of the SLA? 2) How can the set of services offered by the SP be deployed in a cost-efficient manner, while ensuring the appropriate QoS?

The two first papers of the thesis concern the former, which is answered by developing both analytic and simulation-based models. Whether the analytic or simulated-based approach should be preferred is dependent on the underlying properties of the services. The second question is considered in the three remaining papers, where optimization models are formulated and solved by both exact and inexact algorithms. Specifically, we provide exact algorithms based on branch and price (B&P) and metaheuristics based on the adaptive large neighborhood search (ALNS) framework. While the B&P approach can provide optimal solutions for small and medium-sized providers, the ALNS approach provides high-quality solutions more quickly.

 

 

Regarding power and use of power in the workplace

"Belønningsmakt, strukturmakt, legitim makt, relasjonsmakt, konspirasjonsmakt, tvangsmakt. Hva er bra med makt? Når blir maktbruk til maktmisbruk? Finnes det en strategi for å håndtere makten til din fordel?"

- Power, by Endre Sjøvold.

Regarding power and use of power in the workplace

"Belønningsmakt, strukturmakt, legitim makt, relasjonsmakt, konspirasjonsmakt, tvangsmakt. Hva er bra med makt? Når blir maktbruk til maktmisbruk? Finnes det en strategi for å håndtere makten til din fordel?"

- Power, by Endre Sjøvold.

Writer Endre Sjøvold has been looking at the use of power in organizations, and established a framework that can help us understand and recognize the many nuances of power. In this book, Sjøvold shows us how power-plays can be used efficiently to affect others; and how you can recognize and defend yourself against abuse of power.

You will also find an excerpt from the book. Read more about the book.

Contact the publisher for more information about the book:

Marketing consultant Maria Almaas
maria.almaas@universitetsforlaget.no / Phone: 926 05 465

 

Gunn Robstad Andersen successful defence of PhD thesis

«Understanding contextual instability, complexity and diversity in an organization undergoing a comprehensive job stress intervention: Implications for work environment, worker health and intervention effect»

Supervisor: Rolf Harald Westgaard 

Gunn Robstad Andersen successful defence of PhD thesis

«Understanding contextual instability, complexity and diversity in an organization undergoing a comprehensive job stress intervention: Implications for work environment, worker health and intervention effect»

Supervisor: Rolf Harald Westgaard 

We congratulate Gunn Robstad Andersen with a successful defence of her PhD, December 7th 2015. The title of her thesis is: 

«Understanding contextual instability, complexity and diversity in an organization undergoing a comprehensive job stress intervention: Implications for work environment, worker health and intervention effect»

The following committee have evaluated the thesis:

  • Professor Lotta Dellve, Högskolan i Borås
  • Seniorforsker Bo Veiersted, Statens arbeidsmiljøinstitutt
  • Professor Kristin Svendsen, NTNU

Professor Kristin Svendsen at the Department of Industrial Economics and Technology Management, NTNU, has administered the committee’s work.

The trial lecture was held on the following topic:

«Sustainable change management in human service organizations»

The candidate’s main supervisor has been professor emeritus Rolf Harald Westgaard, NTNU The candidate’s co-supervisor has been Professor Per Øystein Saksvik, NTNU.

Summary of the thesis:
The aim of the thesis is to examine process and contextual elements assumed to impact on the effect of a work environment intervention in order to understand and explain why such interventions often fail in reaching their stated objectives. The research context is defined by an attempt to improve work environment and worker health in order to reduce sick leave in the Home Care Services (HCS) in a Norwegian municipality, by means of implementing a comprehensive work environment intervention focusing on job stress. This was done during a period of contextual instability in terms of concurrent organizational changes and rationalization measures. At study start, one year after implementation of the work environment intervention, persistent poor work environment conditions and high sick leave indicated lack of positive intervention effect.

The overarching research design is the case study design, yet different methodological approaches were employed in the four papers comprising the thesis. Results show that home care workers (HCWs) are at risk of a multitude of occupational exposures and report severe health complaints in terms of musculoskeletal pain, with individual variations. Despite poor work environment conditions, severe pain scores and high sick leave, the HCWs in general regard the intervention as positive. However, HCWs were simultaneously subjected to new work programs, new technology, restructurings, unit mergers, and management replacements which introduced new sources of time pressure and stress, causing an overall deteriorated work situation. Organizational discrepancy, i.e. stakeholders at different organizational levels holding conflicting appraisals of organizational matters, is found to serve as an important barrier to a well-functioning organization in general and to rationalization measures in particular. Results also show that worker responses to rationalization measures are diverse and involve different effects for sub-groups with regard to perceived work demands and shoulder-neck pain.

In conclusion, the thesis demonstrates that contextual instability (in terms of concurrent organizational changes and rationalizations); complexity (organizational discrepancy) and diversity (in terms of individual variations in perceptions and responses) are significant obstacles to an overall positive intervention effect. These elements are important to examine when trying to understand and explain an apparent lack of work environment intervention effect.

Thale Kvernberg Andersen successful defence of PhD thesis

"The Structuration Model of Organizational ICT Integration: From Involuntary Non-Use of New ICT at Work to Situated Learning" 
Supervisor: Morten Levin

Thale Kvernberg Andersen successful defence of PhD thesis

"The Structuration Model of Organizational ICT Integration: From Involuntary Non-Use of New ICT at Work to Situated Learning" 
Supervisor: Morten Levin

We congratulate Thale Kvernberg Andersen with a successful defence of her PhD, December 17th 2015.

The title of the thesis is:

«The Structuration Model of Organizational ICT integration: From Involuntary Non-Use of New ICT at Work to Situated Learning»

The following committee has evaluated the thesis:

Associate Professor Ola Edvin Vie at the Department of Industrial Economics and Technology Management, NTNU, has administered the committee’s work.

The trial lecture was held on the following topic:

«The problem of agency in analyses of ICT implementation»

The candidate’s main supervisor has been Professor Morten Levin, NTNU. The candidate’s co-supervisor has been Professor Per Øystein Saksvik, NTNU.

Ahmad Hemmati successful defence of PhD thesis

«Optimization models and methods for maritime cargo and inventory routing problems»

Supervisor: Lars Magnus Hvattum

«Optimization models and methods for maritime cargo and inventory routing problems»

Supervisor: Lars Magnus Hvattum

Ahmad Hemmati successful defence of PhD thesis

We congratulate Ahmad Hemmati with successful defence of his PhD, September 22 2015. The title of his thesis is:

«Optimization models and methods for maritime cargo and inventory routing problems»

The following committee have evaluated the thesis:
Professor Kenneth Sörensen, University of Antwerp
Associate Professor Claudia Archetti, University of Brescia
Professor Bjørn Nygreen, NTNU

Professor Bjørn Nygreen at the Department of Industrial Economics and Technology Management, NTNU, has administered the committee’s work.

The trial lecture were held on the followin topic:
«Recent trends in exact (optimisation) algorithms for production scheduling applications»

The candidate’s main supervisor has been Professor Lars Magnus Hvattum, NTNU/Molde University College. The candidate’s co-supervisor has been Professor Marielle Christiansen, NTNU.

The candidate, supervisors and evaluation committee, Photo: Fotograf Elin Iversen

 

Summary of the thesis
This thesis is part of the DOMinant II project. The DOMinant II project is a collaboration between three Norwegian research groups within the field of operations research. The goal of the project is to reduce the gap between the research frontier and the needs of Norwegian and international maritime and road-based transport industry, by developing new models and solution algorithms for computationally challenging discrete optimization problems in this field. As part of the project, the aim of this thesis is to develop models and efficient and effective solution methods for realistic maritime cargo and inventory routing problems.

This thesis consists of four papers. The papers are connected to each other in a way to achieve the goals of the thesis and to partially cover the aims of the DOMinant II project. The first paper provides a benchmark suite for industrial and tramp ship routing and scheduling problems. The second paper considers a problem that combines traditional tramp shipping with a vendor managed inventory (VMI) service and presents a heuristic for realistic sized instances. The effect of offering VMI services to traditional tramp shipping industry is then analyzed. The third paper which covers a large part of the thesis’ purpose, introduces a rich maritime inventory routing problem. In the paper, some realistic features such as considering multiple products and a many-to-many distribution structure make the problem very complex. A hybrid matheuristic is developed to solve realistic instances of the problem within reasonable computing times. The fourth paper focuses on the very well-known ALNS algorithm which is implemented in the first paper, to investigate the role of randomization in this algorithm by using empirical tests through statistical tools. The results indicate that initial implementations of simple straight-forward deterministic alternatives are immediately able to match the performance of the randomized components.

Tue, 08 Nov 2016 11:14:56 +0100