Faculty Development Program in Dokuz Eylül School of Medicine: In the process of curriculum change from traditional to PBL

Introduction: In Dokuz Eylül School of Medicine (DESM) a faculty development program is being carried out by the "Trainers' Training Committee". DESM made a fundamental change in its curriculum from traditional to Problem-based Learning (PBL) in 1997. This was the first implementation of a PBL curriculum in Turkey. Faculty development activities were initiated in the same year. This paper describes the faculty development activities with a special emphasis on PBL courses. Program description: Between 1997-2000 27 four-day long PBL courses were held for 343 participants. The curriculum consisted of PBL philosophy, PBL steps, role of the tutor and students in PBL process, effective case design, assessment principles and group dynamics. PBL simulations enabled the participants to play the roles of both tutors and students. Process evaluation: At the end of the program most of the participants stated that length of the program, content, training methods and the course organization was appropriate. The majority of the participants (89.5%) found the program very useful. PBL steps, PBL practices and PBL philosophy were found as the most useful sessions. Discussion: These courses gave medical staff the opportunity to develop their understanding of PBL methodology and theory. PBL courses and continuous educational activities such as weekly tutor meetings are being held and new courses on advanced tutoring skills are being planned for the near future in DESM

Antioxidant and hepatoprotective effects of vitamin E and melatonin against copper-induced toxicity in rats

Purpose: To determine the preventive effects of vitamin E and melatonin against acute copper toxicity in rats.Methods: A total of 28 Wistar albino rats were randomly divided into four equal groups: control, copper sulfate, copper sulfate + vitamin E, and copper sulfate + melatonin. The following were analyzed in all groups: serum enzymes; activity of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx), protein carbonyl (PC) content. Liver histopathology was also evaluated.Results: PC levels decreased in rats administered copper sulfate/vitamin E and copper sulfate/melatonin. The activities of SOD, GPx and CAT increased significantly with melatonin and vitamin E administration when compared with administration of copper sulfate alone. Histopathologic features revealed severe degeneration and necrotic changes in rats administered copper sulfate alone. These changes were observed to a lesser extent in the copper sulfate + melatonin group and only minimally in the copper sulfate + vitamin E group.Conclusion: Vitamin E and melatonin are protective against liver damage caused by copper. Vitamin E, and melatonin may strengthen the antioxidant defense system by inhibiting protein oxidation and enhancing the activity of antioxidant enzymes.Keywords: Copper, Melatonin, Vitamin E, Protein oxidation, Hepatoprotectiv

Application of solar panel array on a short route ferry : a life cycle and economic assessment

Green technologies are considered to be one of the most significant way to mitigate the severe global warming effect and have been drawing attentions from researchers all over the world. Solar energy is a type of renewable energy and solar panel array can capture and convert solar energy to electricity for domestic and industry uses. This paper considers the application of solar panel array to propulsion system of a short route ferry operating in the Marmara Sea where currently no environment protection policy is active to guide marine activities. The evaluation of the application is carried out using life cycle assessment from the aspect of cost effective and environment friendly. To take the payback time of the system into account, this study investigate the difference due to different average daily sunny hours in the operating area considering three levels of carbon credits. The results indicates both average daily sunny hours and carbon credits have an impact on the payback time. With the highest average daily sunny hours and carbon credits, the payback time of the application is only 2 years

Life cycle and economic assessment of a solar panel array applied to a short route ferry

This paper was to investigate the potential benefits of solar panel systems if applied for obtaining propulsion power of a short route ferry operating in the Marmara Sea. The life cycle assessment was applied to evaluate the long-term environmental impact of the solar power systems on-board in replace of conventional diesel engine systems. The cost and benefit of such systems were evaluated through the economic assessment where the life cycle cost relative to installation, operation and recycling of the solar panels, fuel savings and payback time were considered. Research findings revealed the payback time would be around three years, whereas the accumulative fuel cost saving would be over $300,000 by the end of vessel life. The sensitivity analysis using two varying parameters - energy efficiency and investment cost - implied, that the longer payback time would be positively associated with lower energy efficiencies and higher investment costs. It was also suggested that the marginal cost of the carbon credit should be$ 190 per tonne or higher to make the shipping business successful

Failure modes and criticality analysis of the preliminary design phase of the Mars Desert Research Station considering human factors

This work presents an extension to the traditional FMECA (Failure Modes, Effects and Criticality Analysis) method to include the effects of human factors concerning accessibility/repairability, probability of contact and degree of contact. The authors refer to this extension to the traditional FMECA as the Human Design Approach (HDA). All data used in this study was collected during the stay of two of the authors at the Mars Desert Research Station (MDRS) in the Utah desert, USA. The MDRS is a laboratory for carrying out research in order to understand and investigate the difficulties of how to live and work on another planet. The results show that following the HDA can enhance the safety and reliability of the MDRS. There is still a significant amount of research required concerning reliability analysis of the space habitat in terms of the selection of optimum designs, the modification of systems, as well as access, inspection and maintenance strategies, human factors and environmental impacts. This preliminary study will assist the design engineers with the selection of an optimum configuration for space habitats and can be extended to any case where humans can influence function of an environment

Numerical investigation of the behaviour and performance of ships advancing through restricted shallow waters

Upon entering shallow waters, ships experience a number of changes due to the hydrodynamic interaction between the hull and the seabed. Some of these changes are expressed in a pronounced increase in sinkage, trim and resistance. In this paper, a numerical study is performed on the Duisburg Test Case (DTC) container ship using Computational Fluid Dynamics (CFD), the Slender-Body theory and various empirical methods. A parametric comparison of the behaviour and performance estimation techniques in shallow waters for varying channel cross-sections and ship speeds is performed. The main objective of this research is to quantify the effect a step in the channel topography on ship sinkage, trim and resistance. Significant differences are shown in the computed parameters for the DTC advancing through dredged channels and conventional shallow water topographies. The different techniques employed show good agreement, especially in the low speed range

A comparative study on the design of an environmentally friendly RoPax ferry using CFD

RoPax ferries are designed for maximum efficiency, enabling smooth loading and unloading of cars, cargo and passengers. When optimising successful RoPax design, a compromise is always made between a light and compact hull geometry with diminished power requirement whilst providing substantial car and passenger capacities. In response to recent computational developments, Computational Fluid Dynamics (CFD) is a widely-used design tool amongst naval architects owing to its more accurate results compared to conventional potential flow theory based techniques. By combining CFD tools with Computer Aided Design (CAD) software, it is possible to obtain useful results at an early stage of a typical ship design process. The key objective of this paper is to design an environmentally friendly RoPax ferry utilising CAD and CFD tools. This aim was achieved by developing a new RoPax design with a new green power plant configuration releasing less greenhouse gas (GHG) emissions to the atmosphere. The performance of the green power plant was assessed through making a comparison to other power plant options. It is clearly shown in the paper that the hybrid LNG turbine is the most environmentally-friendly power option amongst the two other power plants investigated in this piece of research

Optimisation of operational modes of short-route ferry : a life cycle assessment case study

Owing to high operation cost of traditional power systems and serious environmental situation, the usage of hybrid power system on board is increasingly attracting attentions. Applying life cycle assessment (LCA) approach, the key objective of this paper is to evaluate and optimise the operational modes of hybrid power system for a short-route ferry in Scotland. The applied hybrid system is mainly comprised of generators and lithium ion batteries and there are four operational modes based on the power requirements during voyages. To carry out this study, a top-bottom design strategy is applied to build up the short route ferry with hybrid power system in GaBi. The cradle to grave of the ferry is modelled referring to a practical ship life: con-struction, operation, maintenance and dismantling. In order to determine the optimal power distribution and minimal emissions, a series of operation profile cases with different power distributions were investigated for a certain route with following operational phases: transiting, manoeuvring and at slip. The comparison results from different voyage phases indicated the optimal power distribution between gen-sets and batteries with minimised operation costs. The environmental assessments for each case were carried out in order to identify the relationship between power distributions and emissions. The study concluded that there are sig-nificant impacts on the energy consumption and environment during the life cycle of a hybrid power system and therefore it is essential to apply appropriate operation optimisation on the system

Multi-criteria decision-making for marine propulsion : hybrid, diesel electric and diesel mechanical systems from cost-environment-risk perspectives

The paper introduces a new decision-making process which is used to compare the performance of a ship with either diesel electric hybrid propulsion or conventional propulsion systems. A case study was carried out to compare the performance of both propulsions from cost, environmental and risk perspectives. This paper also overviews the modern approaches of multi-criteria decision-making and highlights some of their shortcomings in particular the fact that these approaches often rely on different criteria such as financial, environmental or risk. This paper aims to overcome this shortcoming by enhancing the process of multi-criteria decision analysis. The key process in this research was to convert all incomparable values into monetary values, thereby enabling the impacts of each criterion to be compared and integrated in a straightforward manner. Results of the case study showed that the use of a hybrid propulsion system could reduce annual operational costs by $300,000 (2$1 million (7 %) compared to a diesel mechanical propulsion system. In order to investigate the optimal use of the hybrid propulsion system, various operational scenarios were identified and applied to the proposed decision-making process. The results showed that operating the ship in hybrid mode during manoeuvring and berthing is more desirable as the holistic cost can reduce in almost $1 million. The advantages of the proposed decision making process was illustrated by comparing the results obtained from a conventional decision-making process using the analytical hierarchical method. It is believed that the research findings not only present general understanding of the possible advantages of hybrid propulsion for stakeholders, but provide them with an insight into the enhanced approach into the multi-criteria decision analysis

An effective framework for life cycle and cost assessment for marine vessels aiming to select optimal propulsion systems

By adopting the concept of modularity, this paper introduced an optimal framework which facilitates life cycle assessment and life cycle cost assessment, thereby supporting rapid and reliable decision-making in the marine industry. The benefits of the proposed framework were discussed through two case studies where the optimal configurations of marine propulsion systems were determined from the economic and environmental perspectives. First, the performance of a short-route ferry using the hybrid system was compared with those of equivalent ships using diesel-electric and diesel-mechanical propulsion systems respectively. Research findings revealed the excellence of the hybrid system in both economic and environmental aspects. Second, the same method was applied to an offshore tug vessel to determine an optimal engine configuration. Results of analysis emphasised that the selection of multiple small-sized engines is more effective than two medium-sized engines. Both studies have proven that the proposed framework would be useful and practical for accelerating the life cycle analysis which allows ship designers and owners to obtain the long-term view of economic and environmental impacts for particular products or systems without demanding process. The paper also opened up the possibility of extending the application of the proposed framework to the areas where proper decision-making is essential but under-used