Bulletin officiel de la transportation à la Guyane

1902.

Bulletin officiel de la transportation à la Guyane

1890/03 (N3).

Bulletin officiel de la transportation à la Guyane

1903/04 (A1903,N4).

Experimental analysis of optimization techniques on the road passenger transportation problem

Analyzing the state of the art in a given field in order to tackle a new problem is always a mandatory task. Literature provides surveys based on summaries of previous studies, which are often based on theoretical descriptions of the methods. An engineer, however, requires some evidence from experimental evaluations in order to make the appropriate decision when selecting a technique for a problem. This is what we have done in this paper: experimentally analyzed a set of representative state-of-the-art techniques in the problem we are dealing with, namely, the road passenger transportation problem. This is an optimization problem in which drivers should be assigned to transport services, fulfilling some constraints and minimizing some function cost. The experimental results have provided us with good knowledge of the properties of several methods, such as modeling expressiveness, anytime behavior, computational time, memory requirements, parameters, and free downloadable tools. Based on our experience, we are able to choose a technique to solve our problem. We hope that this analysis is also helpful for other engineers facing a similar problem

Feasibility study of the available relay protection solutions for microgrids

Thesis talks about relay protection for microgrids. Microgrid operation sets more challenges than traditional utility grid protection because of lower fault current levels. Solutions for these challenges are discussed in this paper. Thesis also studies available relay protection solutions and figures out how they would fit for microgrid protection.

Improving Transportation and Warehousing Efficiency with Simulation-Based Decision Support Systems

Transportation and warehousing are large and growing sectors in the society, and their efficiency is of high importance. Transportation also has a large share of global carbondioxide emissions, which are one the leading causes of anthropogenic climate warming. Various countries have agreed to decrease their carbon emissions according to the Kyoto protocol. Transportation is the only sector where emissions have steadily increased since the 1990s, which highlights the importance of transportation efficiency. The efficiency of transportation and warehousing can be improved with the help of simulations, but models alone are not sufficient. This research concentrates on the use of simulations in decision support systems. Three main simulation approaches are used in logistics: discrete-event simulation, systems dynamics, and agent-based modeling. However, individual simulation approaches have weaknesses of their own. Hybridization (combining two or more approaches) can improve the quality of the models, as it allows using a different method to overcome the weakness of one method. It is important to choose the correct approach (or a combination of approaches) when modeling transportation and warehousing issues. If an inappropriate method is chosen (this can occur if the modeler is proficient in only one approach or the model specification is not conducted thoroughly), the simulation model will have an inaccurate structure, which in turn will lead to misleading results. This issue can further escalate, as the decision-maker may assume that the presented simulation model gives the most useful results available, even though the whole model can be based on a poorly chosen structure. In this research it is argued that simulation- based decision support systems need to take various issues into account to make a functioning decision support system. The actual simulation model can be constructed using any (or multiple) approach, it can be combined with different optimization modules, and there needs to be a proper interface between the model and the user. These issues are presented in a framework, which simulation modelers can use when creating decision support systems. In order for decision-makers to fully benefit from the simulations, the user interface needs to clearly separate the model and the user, but at the same time, the user needs to be able to run the appropriate runs in order to analyze the problems correctly. This study recommends that simulation modelers should start to transfer their tacit knowledge to explicit knowledge. This would greatly benefit the whole simulation community and improve the quality of simulation-based decision support systems as well. More studies should also be conducted by using hybrid models and integrating simulations with Graphical Information Systems.

Survey of transportation of liquid bulk chemicals in the Baltic Sea

This study is made as a part of the Chembaltic (Risks of Maritime Transportation of Chemicals in Baltic Sea) project which gathers information on the chemicals transported in the Baltic Sea. The purpose of this study is to provide an overview of handling volumes of liquid bulk chemicals (including liquefied gases) in the Baltic Sea ports and to find out what the most transported liquid bulk chemicals in the Baltic Sea are. Oil and oil products are also viewed in this study but only in a general level. Oils and oil products may also include chemical-related substances (e.g. certain bio-fuels which belong to MARPOL annex II category) in some cargo statistics. Chemicals in packaged form are excluded from the study. Most of the facts about the transport volumes of chemicals presented in this study are based on secondary written sources of Scandinavian, Russian, Baltic and international origin. Furthermore, statistical sources, academic journals, periodicals, newspapers and in later years also different homepages on the Internet have been used as sources of information. Chemical handling volumes in Finnish ports were examined in more detail by using a nationwide vessel traffic system called PortNet. Many previous studies have shown that the Baltic Sea ports are annually handling more than 11 million tonnes of liquid chemicals transported in bulk. Based on this study, it appears that the number may be even higher. The liquid bulk chemicals account for approximately 4 % of the total amount of liquid bulk cargoes handled in the Baltic Sea ports. Most of the liquid bulk chemicals are handled in Finnish and Swedish ports and their proportion of all liquid chemicals handled in the Baltic Sea is altogether over 50 %. The most handled chemicals in the Baltic Sea ports are methanol, sodium hydroxide solution, ammonia, sulphuric and phosphoric acid, pentanes, aromatic free solvents, xylenes, methyl tert-butyl ether (MTBE) and ethanol and ethanol solutions. All of these chemicals are handled at least hundred thousand tonnes or some of them even over 1 million tonnes per year, but since chemical-specific data from all the Baltic Sea countries is not available, the exact tonnages could not be calculated in this study. In addition to these above-mentioned chemicals, there are also other high volume chemicals handled in the Baltic Sea ports (e.g. ethylene, propane and butane) but exact tonnes are missing. Furthermore, high amounts of liquid fertilisers, such as solution of urea and ammonium nitrate in water, are transported in the Baltic Sea. The results of the study can be considered indicative. Updated information about transported chemicals in the Baltic Sea is the first step in the risk assessment of the chemicals. The chemical-specific transportation data help to target hazard or e.g. grounding/collision risk evaluations to chemicals that are handled most or have significant environmental hazard potential. Data gathered in this study will be used as background information in later stages of the Chembaltic project when the risks of the chemicals transported in the Baltic Sea are assessed to highlight the chemicals that require special attention from an environmental point of view in potential marine accident situations in the Baltic Sea area.

Oil Transportation in the Gulf of Finland in 2020 and 2030

This study is part of the Minimizing risks of maritime oil transport by holistic safety strategies (MIMIC) project. The purpose of this study is to provide a current state analysis of oil transportation volumes in the Baltic Sea and to create scenarios for oil transportation in the Gulf of Finland for the years 2020 and 2030. Future scenarios and information about oil transportation will be utilized in the modelling of oil transportation risks, which will be carried out as part of the MIMIC project. Approximately 290 million tons of oil and oil products were transported in the Baltic Sea in 2009, of which 55% (160 million tons) via the Gulf of Finland. Oil transportation volumes in the Gulf of Finland have increased from 40 million to almost 160 million tonnes over the last ten years. In Russia and Estonia, oil transportation mainly consists of export transports of the Russian oil industry. In Finnish ports in the Gulf of Finland, the majority of oil traffic is concentrated to the port of Sköldvik, while the remainder mainly consists of different oil products for domestic use. Transit transports to/from Russia make up small volumes of oil transportation. The largest oil ports in the Gulf of Finland are Primorsk, Tallinn, St. Petersburg and Sköldvik. The basis for the scenarios for the years 2020 and 2030 is formed by national energy strategies, the EU`s climate and energy strategies as well other energy and transportation forecasts for the years 2020 and 2030. Three alternative scenarios were produced for both 2020 and 2030. The oil volumes are based on the expert estimates of nine specialists. The specialists gave three volumes for each scenario: the expected oil transport volumes, and the minimum and maximum volumes. Variations in the volumes between the scenarios are not large, but each scenario tends to have rather a large difference between the figures for minimum and maximum volumes. This variation between the minimum and maximum volumes ranges around 30 to 40 million tonnes depending on the scenario. On the basis of this study, no a dramatic increase in oil transportation volumes in the Gulf of Finland is to be expected. Most of the scenarios only forecasted a moderate growth in maritime oil transportation compared to the current levels. The effects of the European energy policy favouring renewable energy sources can be seen in the 2030 scenarios, in which the transported oil volumes are smaller than in the 2020 scenarios. In the Slow development 2020 scenario, oil transport volumes for 2020 are expected to be 170.6 Mt (million tonnes), in the Average development 2020 187.1 Mt and in the Strong development 2020 201.5 Mt. The corresponding oil volumes for the 2030 scenarios were 165 Mt for the Stagnating development 2030 scenario, 177.5 Mt for the Towards a greener society 2030 scenario and 169.5 Mt in the Decarbonising society 2030 scenario.

Liquid transportation and distribution during (re)wetting : impact on coated papers in printing

In many industrial applications, such as the printing and coatings industry, wetting of porous materials by liquids includes not only imbibition and permeation into the bulk but also surface spreading and evaporation. By understanding these phenomena, valuable information can be obtained for improved process control, runnability and printability, in which liquid penetration and subsequent drying play important quality and economic roles. Knowledge of the position of the wetting front and the distribution/degree of pore filling within the structure is crucial in describing the transport phenomena involved. Although exemplifying paper as a porous medium in this work, the generalisation to dynamic liquid transfer onto a surface, including permeation and imbibition into porous media, is of importance to many industrial and naturally occurring environmental processes. This thesis explains the phenomena in the field of heatset web offset printing but the content and the analyses are applicable in many other printing methods and also other technologies where water/moisture monitoring is crucial in order to have a stable process and achieve high quality end products. The use of near-infrared technology to study the water and moisture response of porous pigmented structures is presented. The use of sensitive surface chemical and structural analysis, as well as the internal structure investigation of a porous structure, to inspect liquid wetting and distribution, complements the information obtained by spectroscopic techniques. Strong emphasis has been put on the scale of measurement, to filter irrelevant information and to understand the relationship between interactions involved. The near-infrared spectroscopic technique, presented here, samples directly the changes in signal absorbance and its variation in the process at multiple locations in a print production line. The in-line non-contact measurements are facilitated by using several diffuse reflectance probes, giving the absolute water/moisture content from a defined position in the dynamic process in real-time. The nearinfrared measurement data illustrate the changes in moisture content as the paper is passing through the printing nips and dryer, respectively, and the analysis of the mechanisms involved highlight the roles of the contacting surfaces and the relative liquid carrier properties of both non-image and printed image areas. The thesis includes laboratory studies on wetting of porous media in the form of coated paper and compressed pigment tablets by mono-, dual-, and multi-component liquids, and paper water/moisture content analysis in both offline and online conditions, thus also enabling direct sampling of temporal water/moisture profiles from multiple locations. One main focus in this thesis was to establish a measurement system which is able to monitor rapid changes in moisture content of paper. The study suggests that near-infrared diffuse reflectance spectroscopy can be used as a moisture sensitive system and to provide accurate online qualitative indicators, but, also, when accurately calibrated, can provide quantification of water/moisture levels, its distribution and dynamic liquid transfer. Due to the high sensitivity, samples can be measured with excellent reproducibility and good signal to noise ratio. Another focus of this thesis was on the evolution of the moisture content, i.e. changes in moisture content referred to (re)wetting, and liquid distribution during printing of coated paper. The study confirmed different wetting phases together with the factors affecting each phase both for a single droplet and a liquid film applied on a porous substrate. For a single droplet, initial capillary driven imbibition is followed by equilibrium pore filling and liquid retreat by evaporation. In the case of a liquid film applied on paper, the controlling factors defining the transportation were concluded to be the applied liquid volume in relation to surface roughness, capillarity and permeability of the coating giving the liquid uptake capacity. The printing trials confirmed moisture gradients in the printed sheet depending on process parameters such as speed, fountain solution dosage and drying conditions as well as the printed layout itself. Uneven moisture distribution in the printed sheet was identified to be one of the sources for waving appearance and the magnitude of waving was influenced by the drying conditions.

Validation and Selection of Transportation Cost Drivers with Advanced Methods

In today's logistics environment, there is a tremendous need for accurate cost information and cost allocation. Companies searching for the proper solution often come across with activity-based costing (ABC) or one of its variations which utilizes cost drivers to allocate the costs of activities to cost objects. In order to allocate the costs accurately and reliably, the selection of appropriate cost drivers is essential in order to get the benefits of the costing system. The purpose of this study is to validate the transportation cost drivers of a Finnish wholesaler company and ultimately select the best possible driver alternatives for the company. The use of cost driver combinations as an alternative is also studied. The study is conducted as a part of case company's applied ABC-project using the statistical research as the main research method supported by a theoretical, literature based method. The main research tools featured in the study include simple and multiple regression analyses, which together with the literature and observations based practicality analysis forms the basis for the advanced methods. The results suggest that the most appropriate cost driver alternatives are the delivery drops and internal delivery weight. The possibility of using cost driver combinations is not suggested as their use doesn't provide substantially better results while increasing the measurement costs, complexity and load of use at the same time. The use of internal freight cost drivers is also questionable as the results indicate weakening trend in the cost allocation capabilities towards the end of the period. Therefore more research towards internal freight cost drivers should be conducted before taking them in use.

Potential for Greenhouse Gas Emission Reductions by Using Biomethane as a Road Transportation Fuel

The aim of this thesis is to study whether the use of biomethane as a transportation fuel is reasonable from climate change perspective. In order to identify potentials and challenges for the reduction of greenhouse gas (GHG) emissions, this dissertation focuses on GHG emission comparisons, on feasibility studies and on the effects of various calculation methodologies. The GHG emissions calculations are carried out by using life cycle assessment (LCA) methodologies. The aim of these LCA studies is to figure out the key parameters affecting the GHG emission saving potential of biomethane production and use and to give recommendations related to methodological choices. The feasibility studies are also carried out from the life cycle perspective by dividing the biomethane production chain for various operators along the life cycle of biomethane in order to recognize economic bottlenecks. Biomethane use in the transportation sector leads to GHG emission reductions compared to fossil transportation fuels in most cases. In addition, electricity and heat production from landfill gas, biogas or biomethane leads to GHG reductions as well. Electricity production for electric vehicles is also a potential route to direct biogas or biomethane energy to transportation sector. However, various factors along the life cycle of biomethane affect the GHG reduction potentials. Furthermore, the methodological selections have significant effects on the results. From economic perspective, there are factors related to different operators along the life cycle of biomethane, which are not encouraging biomethane use in the transportation sector. To minimize the greenhouse gas emissions from the life cycle of biomethane, waste feedstock should be preferred. In addition, energy consumption, methane leakages, digestate utilization and the current use of feedstock or biogas are also key factors. To increase the use of biomethane in the transportation sector, political steering is needed to improve the feasibility for the operators. From methodological perspective, it is important to recognize the aim of the life cycle assessment study. The life cycle assessment studies can be divided into two categories: 1.) To produce average GHG information of biomethane to evaluate the acceptability of biomethane use compared to fossil transportation fuels. 2.) To produce GHG information of biomethane related to actual decision-making situations. This helps to figure out the actual GHG emission changes in cases when feedstock, biogas or biomethane are already in other use. For example directing biogas from electricity production to transportation use does not necessarily lead to additional GHG emission reductions. The use of biomethane seems to have a lot of potential for the reduction of greenhouse gas emissions as a transportation fuel. However, there are various aspects related to production processes, to the current use of feedstock or biogas and to the feasibility that have to be taken into account.

Developing short sea shipping transportation chains at Helsinki-Tallinn route

Short sea shipping is an important part of the European economy and an alternative to road transport of goods in Europe. It represents an intermodal transport combination of sea and land on a Door-to-Door basis, and it aims to develop more sustainable transport network with the least negative impacts by the transport modes. This Master’s thesis addresses the development of short sea shipping transportation chains at Helsinki-Tallinn route. The Master´s thesis explores the development of short sea shipping at Helsinki-Tallinn route by analyzing the shipping costs per unit transported by different ship types and sizes between port of Helsinki-Vuosaari harbour and port of Tallinn-Muuga harbour, and examining the possibility of Ro-Ro traffic as well. The study is qualitative-quantitative method and it is based on a case study, data is collected from secondary and primary sources, and mixed methods analysis is used to implement the interviews and observations results with the databases analysis. In the thesis factors affecting on short sea shipping are explored and analyzed, also the possibility of Ro-Ro shipping is examined, by comparing the shipping cost and the environmental impact of different ships like container ships, Ropax, and CONRO ships. The finding of this research shows the importance of time at port and utilization as a shipping cost determinants, the relationship between ship type and costing, and the possibility of Ro-Ro shipping.

Advanced biofuel production: Engineering metabolic pathways for butanol and propane biosynthesis.

Greenhouse gases emitted from energy production and transportation are dramatically changing the climate of Planet Earth. As a consequence, global warming is affecting the living conditions of numerous plant and animal species, including ours. Thus the development of sustainable and renewable liquid fuels is an essential global challenge in order to combat the climate change. In the past decades many technologies have been developed as alternatives to currently used petroleum fuels, such as bioethanol and biodiesel. However, even with gradually increasing production, the market penetration of these first generation biofuels is still relatively small compared to fossil fuels. Researchers have long ago realized that there is a need for advanced biofuels with improved physical and chemical properties compared to bioethanol and with biomass raw materials not competing with food production. Several target molecules have been identified as potential fuel candidates, such as alkanes, fatty acids, long carbon‐chain alcohols and isoprenoids. The current study focuses on the biosynthesis of butanol and propane as possible biofuels. The scope of this research was to investigate novel heterologous metabolic pathways and to identify bottlenecks for alcohol and alkane generation using Escherichia coli as a model host microorganism. The first theme of the work studied the pathways generating butyraldehyde, the common denominator for butanol and propane biosynthesis. Two ways of generating butyraldehyde were described, one via the bacterial fatty acid elongation machinery and the other via partial overexpression of the acetone‐butanol‐ethanol fermentation pathway found in Clostridium acetobutylicum. The second theme of the experimental work studied the reduction of butyraldehyde to butanol catalysed by various bacterial aldehyde‐reductase enzymes, whereas the final part of the work investigated the in vivo kinetics of the cyanobacterial aldehyde deformylating oxygenase (ADO) for the generation of hydrocarbons. The results showed that the novel butanol pathway, based on fatty acid biosynthesis consisting of an acyl‐ACP thioesterase and a carboxylic acid reductase, is tolerant to oxygen, thus being an efficient alternative to the previous Clostridial pathways. It was also shown that butanol can be produced from acetyl‐CoA using acetoacetyl CoA synthase (NphT7) or acetyl‐CoA acetyltransferase (AtoB) enzymes. The study also demonstrated, for the first time, that bacterial biosynthesis of propane is possible. The efficiency of the system is clearly limited by the poor kinetic properties of the ADO enzyme, and for proper function in vivo, the catalytic machinery requires a coupled electron relay system.

Improving Cost-Efficiency and Reducing Environmental Impacts of Intermodal Transportation with Dry Port Concept – Major Rail Transport Corridor in Baltic Sea Region

Transportation plays a major role in the gross domestic product of various nations. There are, however, many obstacles hindering the transportation sector. Cost-efficiency along with proper delivery times, high frequency and reliability are not a straightforward task. Furthermore, environmental friendliness has increased the importance of the whole transportation sector. This development will change roles inside the transportation sector. Even now, but especially in the future, decisions regarding the transportation sector will be partly based on emission levels and other externalities originating from transportation in addition to pure transportation costs. There are different factors, which could have an impact on the transportation sector. IMO’s sulphur regulation is estimated to increase the costs of short sea shipping in the Baltic Sea. Price development of energy could change the roles of different transport modes. Higher awareness of the environmental impacts originating from transportation could also have an impact on the price level of more polluting transport modes. According to earlier research, increased inland transportation, modal shift and slowsteaming can be possible results of these changes in the transportation sector. Possible changes in the transportation sector and ways to settle potential obstacles are studied in this dissertation. Furthermore, means to improve cost-efficiency and to decrease environmental impacts originating from transportation are researched. Hypothetical Finnish dry port network and Rail Baltica transport corridor are studied in this dissertation. Benefits and disadvantages are studied with different methodologies. These include gravitational models, which were optimized with linear integer programming, discrete-event and system dynamics simulation, an interview study and a case study. Geographical focus is on the Baltic Sea Region, but the results can be adapted to other geographical locations with discretion. Results indicate that the dry port concept has benefits, but optimization regarding the location and the amount of dry ports plays an important role. In addition, the utilization of dry ports for freight transportation should be carefully operated, since only a certain amount of total freight volume can be cost-efficiently transported through dry ports. If dry ports are created and located without proper planning, they could actually increase transportation costs and delivery times of the whole transportation system. With an optimized dry port network, transportation costs can be lowered in Finland with three to five dry ports. Environmental impacts can be lowered with up to nine dry ports. If more dry ports are added to the system, the benefits become very minor, i.e. payback time of investments becomes extremely long. Furthermore, dry port network could support major transport corridors such as Rail Baltica. Based on an analysis of statistics and interview study, there could be enough freight volume available for Rail Baltica, especially, if North-West Russia is part of the Northern end of the corridor. Transit traffic to and from Russia (especially through the Baltic States) plays a large role. It could be possible to increase transit traffic through Finland by connecting the potential Finnish dry port network and the studied transport corridor. Additionally, sulphur emission regulation is assumed to increase the attractiveness of Rail Baltica in the year 2015. Part of the transit traffic could be rerouted along Rail Baltica instead of the Baltic Sea, since the price level of sea transport could increase due to the sulphur regulation. Both, the hypothetical Finnish dry port network and Rail Baltica transport corridor could benefit each other. The dry port network could gain more market share from Russia, but also from Central Europe, which is the other end of Rail Baltica. In addition, further Eastern countries could also be connected to achieve higher potential freight volume by rail.