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Schinas O.,Hamburg School of Business Administration | Stefanakos C.,Technological Educational Institute of Athens
Transportation Research Part C: Emerging Technologies | Year: 2012

Recent marine environment regulatory actions have ignited strong debates and discussions among policy-makers, researchers and operators. This paper provides a methodological framework for the estimation of the cost impact of some of the environmental measurements, and specifically on the increase of operating expenses of seagoing vessels due to the sulfur limits determined by MARPOL Annex VI. A model based on stochastic linear programming is presented that aims to minimize the total cost of an operator, by determining the fleet-mix and the capacity offered under budgetary and fleet attributes constraints, and taking into account demand and growth pattern per period of analysis. The stochastic scenarios are based on the probability of the fleet operating in a Sulfur Emission Control Areas (SECAs). A liner and a tramp shipping applications are presented, and the results are discussed. The paper concludes with a summary of the achieved goals, of the limitations of this model, and the future development of this approach. © 2012 Elsevier Ltd.


Schinas O.,Hamburg School of Business Administration | Butler M.,Intecsea
Ocean Engineering | Year: 2016

Regulatory initiatives obligate maritime operators to reduce emission via retrofitting propulsion and exhaust treatment systems or by using alternative fuels. Although these initiatives facilitate the emergence of LNG as a marine fuel, the proliferation of LNG technology is dependent on the relationship that defines the competitiveness of conventionally fueled and LNG-fueled ships. This article proposes a methodology to evaluate the commercial incentives that are required to promote LNG as a marine fuel, which can be used to assess policy initiatives that encourage the use of alternative technologies and estimate their market impact. To develop the context and support this methodology, the following areas are discussed: (1) international regulatory frameworks and regional initiatives supporting the use of LNG as a marine fuel; (2) commercial and operational attributes that determine the competitiveness of LNG-fueled ships; and (3) challenges preventing the adoption of LNG as a marine fuel, including the uncertainties and less-quantifiable concerns expressed by the maritime operators. © 2016 Elsevier Ltd. All rights reserved.


Stefanakos C.,Sintef | Schinas O.,Hamburg School of Business Administration
WMU Journal of Maritime Affairs | Year: 2015

This work explores the applicability of well-known fuzzy time series forecasting techniques for the prediction of bunker prices. These techniques have extensively been used with great success to the forecasting of stock prices. In the present work, weekly time series of bunker prices in four major world ports (Rotterdam, Houston, Singapore, and Fujairah) have been thoroughly examined and used for the verification of the forecasting performance of the fuzzy models. The following bunker types have been examined: 380cSt (high and low sulphur), 180cSt (high sulphur), marine diesel oil (MDO), and marine gas oil (MGO). To examine the forecasting accuracy, four error measures are used as an evaluation criterion to compare the forecasting performance of the listing models. Before applying the fuzzy forecasting procedure, and in order to remove nonstationarity, both differencing and moving-average are applied to the data. It has been found that all four error measures attain their minimum at the same point Mopt, which in turn gives the closer forecasts to the actual values. As the importance of fuel prices increases, effective forecasting could further benefit operators with compliance issues and financial planning as well as regulators estimating better the timing and the cost of regulation. © 2015, World Maritime University.


Stefanakos C.N.,Sintef | Schinas O.,Hamburg School of Business Administration | Eidnes G.,Sintef
Proceedings of the International Conference on Offshore Mechanics and Arctic Engineering - OMAE | Year: 2014

This work explores the applicability of widely known fuzzy time series forecasting techniques for the prediction of wind and wave data. These techniques have extensively been used with great success to the forecasting of stock prices. In the present work, long-term time series of wind speed, significant wave height, and peak period are examined and used for the verification of the forecasting performance of the fuzzy models. To examine the forecasting accuracy, the root mean squared error (RMSE) is used as an evaluation criterion to compare the forecasting performance of the listing models. As the importance of quality of wind and wave data increases, effective forecasting could further benefit designers of offshore structures and environmental researchers. Copyright © 2014 by ASME.


Schinas O.,Hamburg School of Business Administration | Stefanakos C.,Sintef
Transportation Research Part D: Transport and Environment | Year: 2014

This paper aims to discuss the limitations of the financial assessment of technologies assisting compliance with the sulphur regulations of MARPOL Annex VI, which is commonly adhered to by operators, and to contribute a multi-criteria approach based on the analytic network process (ANP). Financial models like the representative one presented herein are widely used in the industry. The given example is analyzed in order to identify the merits and limitations of this approach. Thereafter, an analytical tool based on the ANP is presented. This could enhance understanding of the problem and support decisions. Furthermore, the tool could assist operators to select the necessary technical alternatives in a better way, and reveal the preferences and relationships among criteria, thus fostering improvement of the decision tools. © 2013 Elsevier Ltd.


Stefanakos C.,Sintef | Schinas O.,Hamburg School of Business Administration
Transportation Research Part C: Emerging Technologies | Year: 2014

This paper suggests a methodological approach for the forecasting of marine fuel prices. The prediction of the bunker prices is of outmost importance for operators, as bunker prices affect heavily the economic planning and financial viability of ventures and determine decisions related to compliance with regulations. A multivariate nonstationary stochastic model available in the literature is being retrieved, after appropriate adjustment and testing. The model belongs to the class of periodically correlated stochastic processes with annual periodic components. The time series are appropriately transformed to become Gaussian, and then are decomposed to deterministic seasonal characteristics (mean value and standard deviation) and a residual time series. The residual part is proved to be stationary and then is modeled as a Vector AutoRegressive Mooving Average (VARMA) process. Finally, using the methodology presented, forecasts of a tetra-variate and an octa-variate time series of bunker prices are produced and are in good agreement with actual values. The obtained results encourages further research and deeper investigation of the driving characters of the multivariate time series of bunker prices. © 2013 Elsevier Ltd.


Schinas O.,Hamburg School of Business Administration | Dionelis C.,Hellenic Railways Organisation
Operations Research/ Computer Science Interfaces Series | Year: 2011

Currently most cargoes leave the terminal by road; in Europe, at least, this trend is not sustainable, and sea-rail and sea-river alternatives shall undertake more loads. The focus of this document lays in Europe, including policy and market trends in the European Union, however the problems and the potential solutions may have a global interest. In the text a thorough examination of policy developments in the fields of rail, inland waterways and intermodality is presented. Environmental issues are also discussed. The data from EUROSTAT is used as a basis for further analysis, where it is revealed that even if there is strong political support, it is questionable as to whether it is feasible to promote these links as soon as 2015 or even 2020. The concept of dry (inland) ports and their function in the canalization of cargoes is also analyzed in view of sea-rail and sea-river links. In the last section, all points are summarized and some recommendations are presented. © Springer Science+Business Media, LLC 2011.


Hartmann S.,Hamburg School of Business Administration | Pohlmann J.,ILS Integrierte Logistik Systeme GmbH hit Technopark
Operations Research/ Computer Science Interfaces Series | Year: 2011

This contribution presents a simulation model that generates arrivals of ships over time at a container terminal. The model includes a quay with a given length, a decision module for assigning berths to ships, and a queue for ships for which currently no berth is available. Such models are applied in practice to examine the capacity of the quay and of the quay cranes in scenarios for expected future workloads and ship arrival patterns. We outline the concept for a simple and general simulation model and present some experimental results based on real data. Subsequently, we discuss various extensions of the model that would be necessary to adapt it to a specific terminal. © Springer Science+Business Media, LLC 2011.


Schinas O.,Hamburg School of Business Administration
WMU Journal of Maritime Affairs | Year: 2013

X-Posse is a Common Learning Action project that aims to promote green logistics through focused training actions. The goal of X-Posse was to develop two innovative training modules; the topics of the modules are focused on operational and entrepreneurial needs of the modern business. The aim was to get the most of the "suppliers" of research and state-of-the-art work and offer it to the industry. X-Posse envisaged to become one more bridge between the academia and the market. This report outlines the goals and the achievements of this project. © 2013 World Maritime University.


Hartmann S.,Hamburg School of Business Administration
Flexible Services and Manufacturing Journal | Year: 2013

This paper discusses an extension of the classical resource-constrained project scheduling problem in which the resource availability as well as the resource request of the activities may change from period to period. While the applicability of this extension should be obvious, we provide a case study in order to emphasize the need for the extension. A real-world medical research project is presented which has a structure that is typical for many other medical and pharmacological research projects that consist of experiments. Subsequently, we provide a mathematical model and analyze some properties of the extended problem setting. We also introduce a new priority rule heuristic that is based on a randomized activity selection mechanism which makes use of so-called tournaments. Finally, we report our computational results for the original data of the medical research project as well as for a set of systematically generated test instances. © 2012 Springer Science+Business Media, LLC.

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