This thesis is an effort to implement Reliability Centered Maintenance “RCM” for C20trains at Tunnelbanan Teknik Stockholm AB. In depth study is performed along withmaintenance team of TBT at center of excellence, a facility for maintenance workshop. RCM is a philosophy or framework to ensure efficient working of assets according todefined and required operating context. In general, the successful implementation ofRCM can achieve improvements through lesser maintenance, operating techniquechanges, and generating inclusive maintenance plan. RCM is also one of the best toolsavailable to identify and prevent equipment failures. Therefore TBT has decided tointroduce RCM to ensure effective services with great confidence and precision. The selection of critical system of C20 train was obligatory to initiate implementation ofRCM, and the door system was considered a very complicated system with maximumfailures that results in traffic disturbances and stoppages. Through literature study,depots & workshop visits, brainstorming engineers & train drivers etc, the requiredtasks to be performed were lay down. A template that illustrates details such as FMECA,risk analysis, current maintenance strategy and the recommended actions wasprepared and new maintenance regime along with the changes in work instructionswere proposed. The cost effectiveness as well as safety assessment was carried out.Moreover, the efficacy of RCM analysis is directly proportional to quality and accuracyof available failure data, and the proposed time scale for thesis was underestimated andthe reason behind was the convolution of CMMS as well as poor quality of failure data. The study results are officially approved by all stakeholders, i.e. SL, MTR Stockholm,MTR HK and TBT. This work can guide the officials to take imperative decisions foroptimization of maintenance practices, also the study for C20 door system can be theroadmap for comprehensive implementation of RCM at TBT Stockholm AB.

Investigating the biosynthesis of long-chain (C20–24) polyunsaturated fatty acids (LC-PUFA), physiologically important compounds including arachidonic acid (ARA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), in fish is crucial to identify dietary requirements for essential fatty acids (EFA). Moreover, knowledge of the C20–24 LC-PUFA biosynthetic capability of farmed fish species enables us to understand their ability to utilise commonly used raw materials such as vegetable oils, which naturally lack LC-PUFA but include C18 PUFA that are metabolic precursors of LC-PUFA. Studies have shown that the potential of a species for LC-PUFA biosynthesis is associated with the complement and function of fatty acyl desaturase (fads) and elongase of very long chain fatty acid (elovl) genes existing in that species. The present study therefore aimed to investigate these genes in the African catfish (Clarias gariepinus), the most commercially important farmed fish in sub-Saharan Africa. A fads2, a fads6 and four elovl (elovl2, elovl4a, elovl4b, elovl8) cDNAs were cloned and functionally characterised by heterologous expression in yeast. The Fads2 was a bifunctional desaturase enzyme with ∆6∆5 and ∆8 activities, and thus catalysing all the desaturation reactions required for ARA and EPA biosynthesis from C18 precursor fatty acids. Moreover, the C. gariepinus Fads2 enzymes also desaturated 24:5n-3 to 24:6n-3, a ∆6 desaturation required for the biosynthesis of DHA through the so-called “Sprecher pathway”. Functional characterisation of Fads6 by heterologous expression in yeast did not reveal its function. With regards to elongases, the C. gariepinus Elovl2 demonstrated the ability to elongate C20 and C22 PUFA and thus complements the Elovl5 with elongase capability towards C18 and C20 PUFA. The Elovl8 was capable of only limited elongation of C18 and C20 PUFA. Elovl4a and Elovl4b, enable the biosynthesis of very long-chain (>C24) fatty acids, compounds with major roles in vision and fertility of vertebrates. The present study confirmed that C. gariepinus possess all the enzymatic capabilities required for the biosynthesis of ARA, EPA and DHA and, therefore, its physiological EFA requirements could be satisfied with dietary provision of C18 PUFA.

Lithium-ion batteries are complex systems and making a simulation model of them is always challenging. A method for producing an accurate model with high capabilities for predicting the behavior of the battery in a time and cost efficient way is desired in this field of work. The aim of this thesis has been to develop a method to be close to the desired method as much as possible, especially in two important aspects, time and cost. The method which is the goal of this thesis should fulfill the below five requirements: 1. Able to produce a generic battery model for different types of lithium-ion batteries 2. No or low cost for the development of the model 3. A time span around one week for obtaining the model 4. Able to predict the most aspects of the battery’s behavior like the voltage, SOC, temperature and, preferably, simulate the degradation effects, safety and thermal aspects 5. Accuracy with less than 15% error The start point of this thesis was the study of current methods for cell modeling. Based on their approach, they are divided into three categories, abstract, black box and white box methods. Each of these methods has its own advantages and disadvantages, but none of them are able to fulfill the above requirements. This thesis presents a method, called “gray box”, which is, partially, a mix of the black and white boxes’ concepts. The gray box method uses values for model’s parameters from different sources. Firstly, some chemical/physical measurements like in the case of the white box method, secondly, some of the physical tests/experiments used in the case of the black box method and thirdly, information provided by cell datasheets, books, papers, journals and scientific databases. As practical part of this thesis, a prismatic cell, EIG C20 with 20Ah capacity was selected as the sample cell and its electrochemical model was produced with the proposed method. Some of the model’s parameters are measured and some others are estimated. Also, the abilities of AutoLion, a specialized software for lithium-ion battery modeling were used to accelerate the modeling process. Finally, the physical tests were used as part of the references for calculating the accuracy of the produced model. The results show that the gray box method can produce a model with nearly no cost, in less than one week and with error around 30% for the HPPC tests and, less than this, for the OCV and voltage tests. The proposed method could, largely, fulfill the five mentioned requirements. These results were achieved even without using any physical tests/experimental data for tuning the parameters, which is expected to reduce the error considerably. These are promising results for the idea of the gray box which is in its nascent stages and needs time to develop and be useful for commercial purposes.

The objective of this paper is to analyze the welfare effects of the European Banana Market Policy. Until 1993, EU countries had a wide variety of separate national policies, ranging from free trade (e.g. Germany) to heavily regulated markets (e.g. Spain, France). On 1 July 1993, the EU's common organization of the market in bananas came into force and established a combined quota-tariff regime with preferential access for ACP and EU suppliers. We estimate the resulting changes in the welfare of consumers, traders and the national governments for all member states of the European Union to identify the winners and losers of this change in the external trade policy. Over the period 1993 to 1998, the cumulated aggregate welfare loss of the consumers amounted to ECU 1408 mill, whereas the international banana traders gained ECU 558 mill. on the EU market. The welfare effect on the national budgets of the EU member states was also positive (ECU 783 mill.) due to higher tariff income. The resulting total deadweight loss of the European Union amounted to ECU 68 mill. As regards the distribution of the welfare effects, the former free trade countries lost welfare, whereas the formerly severely regulated countries gained. In absolute terms the biggest loser of the regime shift is Germany, the biggest winner is France. (authors' abstract) / Series: EI Working Papers / Europainstitut