Dans la première partie on étudie un réseau routier sur lequel circule un trafic entre plusieurs origines et plusieurs destinations. Toutes les caractéristiques du réseau ainsi que les données de trafic sont supposées constantes dans le temps. Sachant que les usagers de ce réseau s'affectent suivant le principe de Wardrop, comment alors en abaissant éventuellement les capacités réelles des arcs du réseau, peut-on minimiser le temps total passé par tous les usagers de ce réseau. Dans la deuxième partie, on étudie les absorbants d'une classe de graphes définie par Claude Benzaken et P. L. Hammer.

Aim: By studying the evolution of the market for package holidays over time we hope to get an understanding of the trends that have characterized the market. By doing so, we can get an idea of where the market is moving towards the future. This knowledge is essential for market participants to establish appropriate strategies that follow market trends. Method: We have used qualitative interviews with people involved in the charter industry. Result & Conclusions: The market is characterized by an increase in Internet orientation, where the travel directory and the physical travel agents are becoming less important. The understanding of climate impacts of travel has increased. More people of the third-generation buy package travels and countries in North Africa and Asia are growing in popularity. We believe the market in the coming years will be characterized by lower prices and lower quality. Travel directories will be replaced by promotional flyers. Marketing will be aimed at the third generation. It will be difficult for physical retailers to retain customers. Interest in countries such as Vietnam, Malaysia and Egypt will increase. Suggestions for future research: “A study of the physical dealer prospects” and “Studies on the consumers’ willingness to pay for environmentally friendly charter” would be interesting.   Contribution of the thesis: An increased understanding of the trends in the charter industry.   Key words: Trend, charter companies, market, marketing, consumers, destinations, resorts, travel directory, Internet, development, future. / Syfte: Genom att studera utvecklingen på marknaden för charterresor över tid hoppas vi få förståelse för vilka trender som har präglat marknaden för charterresor och vilka tendenser vi kan se att utvecklingen rör sig mot. Denna kunskap är nödvändig för att charterbolagen ska kunna upprätta relevanta strategier som följer marknadens utveckling. Metod: Vi har använt oss av kvalitativa intervjuer med personer verksamma inom charterbranschen. Resultat och slutsats: Marknaden karaktäriseras av en ökad internetorientering, där resekatalogen och de fysiska resebyråerna blir allt mindre betydelsefulla. Även kunskapen om resandets klimateffekter har ökat. Allt fler personer av den äldre generationen köper charterresor och länder i Nordafrika och Asien växer i popularitet. Vi bedömer att marknaden de kommande åren kommer att kännetecknas av lägre priser och sämre kvalitet. Resekatalogen ersätts av reklamblad. Marknadsföring kommer att riktas till den äldre generationen. Det blir svårt för fysiska återförsäljare att behålla kunder. Intresset för länder som Vietnam, Malaysia och Egypten kommer att öka.   Förslag till fortsatt forskning: En kartläggning av de fysiska återförsäljarnas framtidsutsikter samt studier om betalningsviljan för miljövänliga charterresor vore intressant Uppsatsens bidrag: Ökad förståelse för utvecklingen i charterbranschen.   Nyckelord: Trend, charterbolag, marknad, marknadsföring, konsument, destination, resmål, resekatalog, internet, utveckling, framtid.

We study energy-efficient power allocation among relays for lifetime maximization in a dual-hop relay network operated by amplify-and-forward relays with battery limitations. Power allocation algorithms are proposed for three different scenarios. First, we study the relay cooperation case where all the relays jointly support transmissions for a targeted data rate. By exploring the correlation of time-varying relay channels, we develop a prediction-based relay cooperation method for optimal power allocation strategy to improve the relay network lifetime over existing methods that do not predict the future channel state, or assume the current channel state remains static in the future. Next, we consider energy-efficient relay selection for the single source-destination case. Assuming finite transmission power levels, we propose a stochastic shortest path approach which gives the optimal relay selection decision to maximize the network lifetime. Due to the high computational complexity, a suboptimal prediction-based relay selection algorithm, directly coming from previous problem, is created. Finally, we extend our study to multiple source-destination case, where relay selection needs to be determined for each source-destination pair simultaneously. The network lifetime in the presence of multiple source-destination pairs is defined as the longest time when all source-destination pairs can maintain the target transmission rate. We design relay-to-destination mapping algorithms to prolong the network lifeii time. They all aim at maximizing the perceived network lifetime at the current time slot. The optimal max-min approach and suboptimal user-priority based approach are proposed with different levels of computational complexity. / UOIT

For most kind of analyses in the field of traffic planning, there is a need for origin--destination (OD) matrices, which specify the travel demands between the origin and destination nodes in the network. This thesis concerns the OD-matrix estimation problem, that is, the calculation of OD-matrices using observed link flows. Both time-independent and time-dependent models are considered, and we also study the placement of link flow detectors. Many methods have been suggested for OD-matrix estimation in time-independent models, which describe an average traffic situation. We assume a user equilibrium to hold for the link flows in the network and recognize a bilevel structure of the estimation problem. A descent heuristic is proposed, in which special attention is given to the issue of calculating the change of a link flow with respect to a change of the travel demand in a certain pair of origin and destination nodes. When a time-dimension is considered, the estimation problem becomes more complex. Besides the problem of distributing the travel demand onto routes, the flow propagation in time and space must also be handled. The time-dependent OD-matrix estimation problem is the subject for two studies. The first is a case study, where the conventional estimation technique is improved through introducing pre-adjustment schemes, which exploit the structure of the information contained in the OD-matrix and the link flow observations. In the second study, an algorithm for time-independent estimation is extended to the time-dependent case and tested for a network from Stockholm, Sweden. Finally, we study the underlying problem of finding those links where traffic flow observations are to be performed, in order to ensure the best possible quality of the estimated OD-matrix. There are different ways of quantifying a common goal to cover as much traffic as possible, and we create an experimental framework in which they can be evaluated. Presupposing that consistent flow observations from all the links in the network yields the best estimate of the OD-matrix, the lack of observations from some links results in a relaxation of the estimation problem, and a poorer estimate. We formulate the problem to place link flow detectors as to achieve the least relaxation with a limited number of detectors.

Para el logro de un desarrollo sano es de vital importancia contar con un equilibrio económico en los diferentes rubros de la actividad productiva de las ciudades hermanas (CJS- ELP) y no sólo concretarse al ámbito de la 'maquila'. Si bien el turismo como una opción es viable, su incorporación como forma activa para otras regiones económicas del mismo estado no se ha presentado, de manera que la búsqueda de alternativas para atraer visitantes es aún un desafío para la actividad turística de Juárez-El Paso. La interrogante para los inversionistas y el gobierno es cómo encaminar los esfuerzos en la actividad turística que permitan un crecimiento armónico en la región binacional.La nvestigación, plantea valorar el fenómeno del turismo transfronterizo y se acomete una aproximación de las condiciones reticulares de los actores- stakeholders del turismo de la actividad turística en la frontera México - Estados Unidos bajo un entorno de inseguridad, mediante el análisis del caso de las ciudades hermanas de Ciudad Juárez - El Paso. Los objetivos específicos del examen reticular permiten concebir una relación entre la conformación de redes dinámicas en un espacio territorial fronterizo con potencialidades de alianzas, colaboración y cooperación en un destino binacional. / To achieve healthy development is essential to have an economic balance in the different areas of productive activity in the sister cities (CJS-ELP) and not only realized the scope of the 'maquila'. While tourism is a viable option, its incorporation as a proactive manner to other economic regions of the state has not been submitted, so that the search for alternatives to attract visitors is still a challenge for tourism in Juarez - El Paso. The question for investors and the government is how to direct efforts in tourism to allow balanced growth in the binational region. The research raises assess the phenomenon of cross-border tourism and begin an approximation of the reticular conditions of the actors- stakeholders in tourism in the Mexico - United States under a climate of insecurity, by analyzing the case of sister cities of Ciudad Juárez - El Paso. The specific objectives of the reticular review design allow a relationship between the formation of dynamic networks in a territorial area bordering potential partnerships, collaboration and cooperation in a bi-national destiny.

The meeting industry is a growing industry around the world, and the technological development in recent decades is one of the contributing factors to the increased travel opportunities and meeting industry's expansion. It can be assumed that the technology could replace some of the personal meetings, but humans have always had a need to meet in physical locations in work related purposes, therefore there is no evidence that personal meetings will disappear. Technological development should be seen as complementary rather than a substitute to the existing professional meetings. Public and private sectors within countries has drawn attention to meeting industry's potential, as favored destinations in terms of economic administration, image creation, expansion and acquisition of further market share in the global market. Meeting industry is complex precisely because there are so many different actors and stakeholders that integrate. For a destination to differentiate them and excel in the increasingly global world needed an elaborate marketing plan and effective cooperation between the various actors at the destination. Usually the largest professional meetings takes place in cities where there is capacity to receive large numbers of visitors. Essential elements for sustainable meeting industry are mutually dependent network relationships with strong organizational skills, and are of primary importance to a functioning whole. Among the various meeting actors, Convention Bureau occupy key role as the representative, the primary aim is to market the destination, display options, and finally bring together stakeholders with meeting participants. Lack of a Convention Bureau inhibit communication between meeting participants and stakeholders, also weakened the meeting related image because of incomplete representation.

This bachelor thesis in tourism studies focuses on people's use of social media related to travel. The paper aims to provide a wider knowledge of tourist’s propensity to display destinations through social media and how they perceive others that display travelling. This is put in relation to the term of social status in order to find out if there is a possible link. The intention was to provide an insight into the phenomenon to contribute new awareness that destinations can exploit in their marketing. The theoretical background is presented as a current state of knowledge regarding the topic social media and social status. This section also includes theories regarding the complexity of destination marketing, and also involves concepts such as viral marketing and word-of-mouth. The intention with the theoretical background was to support the empirical material in the analysis. The method used consists of qualitative interviews involving eight individuals. Questions were asked about their use of social media related to travel and identity. The results of the analysis were based on this empirical data, set against the theoretical background. The conclusions that could be drawn is that people's willingness to display destinations depends as much on practical circumstances, as by the desire to present a positive self-image through social media. The demonstration of travelling is also controlled by the individual’s perception on what is most sought after on a social status level. Travelling is a social status-enhancing activity that is associated with positive characteristics, such as knowledge about other cultures. The study has also shown that people are influenced by others displaying travelling. What governs the degree of influence in a positive sense is the perception of shared preferences. When these are coherent, a very effective word-of-mouth marketing can occur. This custom made marketing can help solving problems regarding the complexity of destination marketing. / Denna studie i turismsvetenskap handlar om människors användning av sociala medier kopplat till resande. Uppsatsen syftar till att skapa en bredare kunskap kring turisters benägenhet att visa upp destinationer via sociala medier, samt hur de uppfattar andra som visar upp resande. Detta ställs även mot begreppet social status för att ta reda på om det finns ett eventuellt samband. Intentionen var att ge en inblick i fenomenet för att bidra med nya insikter om huruvida destinationer kan utnyttja detta i sin marknadsföring. Studiens teoretiska bakgrund syftade till att visa upp ett kunskapsnuläge gällande ämnet. Här belyses kunskapsteorier kring sociala medier och social status. Avsnittet innefattar även teorier kring destinationsmarknadsföringens särart, samt involverar begrepp som viral marknadsföring och word-of-mouth. Avsikten med denna teoribildning var att utgöra ett stöd åt det empiriska materialet i analysen. Metoden i denna uppsats utgörs av kvalitativa öppna intervjuer som involverade åtta informanter. Frågorna som ställdes handlade om deras användning av sociala medier kopplat till resande och identitetsskapande. Resultatet i analysen bygger på det empiriska material som framtogs med hjälp av intervjuerna, ställt mot den teoretiska bakgrunden. Enligt slutsatserna i denna uppsats styrs människors benägenhet att visa upp resmål dels av praktiska förutsättningar, dels av viljan att visa upp en positiv image via sociala medier. Uppvisandet styrs även av vad individen personligen anser vara mest eftertraktat på social nivå. Resande är enligt resultatet en statushöjande aktivitet då det förknippas med positiva egenskaper, som exempelvis att känna andra kulturer. Studien har även visat att människor påverkas av andras reseuppvisande. Det som styr graden av påverkan i positiv bemärkelse är uppfattningen av gemensamma preferenser. När dessa är samstämmiga uppstår således en mycket effektiv word-of-mouth marknadsföring. Därmed blir denna typ av marknadsföring skräddarsydd på ett sätt som kan lösa problematiken kring destinationers multisåldhet.

This study contributes to the literature on national long-distance travel demand modeling by providing an analysis of households' annual destination choices and time allocation patterns for long-distance leisure travel purposes. An annual vacation destination choice and time allocation model is formulated to simultaneously predict the different destinations that a household visits and the time it spends on each of these visited destinations, in a year. The model takes the form of a Multiple Discrete-Continuous Extreme Value (MDCEV) structure (Bhat, 2005; Bhat, 2008). The model assumes that households allocate their annual vacation time to visit one or more destinations in a year to maximize the utility derived from their choices. The model framework accommodates variety-seeking in households' vacation destination choices in that households can potentially visit a variety of destinations rather than spending all of their annual vacation time for visiting a single destination. At the same time, the model accommodates corner solutions to recognize that households may not necessarily visit all available destinations. An annual vacation time budget is also considered to recognize that households may operate under time budget constraints. Further, the paper proposes a variant of the MDCEV model that avoids the prediction of unrealistically small amounts of time allocation to the chosen alternatives. To do so, the continuously non-linear utility functional form in the MDCEV framework is replaced with a combination of a linear and non-linear form. The empirical data for this analysis comes from the 1995 American Travel Survey Data, with the U.S. divided into 210 alternative destinations. The empirical analysis provides important insights into the determinants of households' leisure destination choice and time allocation patterns. An appealing feature of the proposed model is its applicability in a national, long-distance leisure travel demand model system. The annual destination choices and time allocations predicted by this model can be used for subsequent analysis of the number of trips made (in a year) to each destination and the travel choices for each trip. The outputs from such a national travel modeling framework can be used to obtain national-level Origin-Destination demand tables for long-distance leisure travel.

Syftet med denna studie är att undersöka vad destinationsmarknadsföringsorganisationerna (DMC) Stockholm Visitor Board och Destination har för syn gällande sociala medier. Samt att titta på hur dessa två arbetar med sociala medier i sin marknadsföring och även vilka fördelar och nackdelar en sådan marknadsföring kan ha. Studien har haft en kvalitativ utgångspunkt när det gäller metodval. Men ett inslag av kvantitativa aspekter har förekommit då en enkätstudie har utförts. Flertalet kvalitativa intervjuer har ägt rumt med relevanta personer för denna studie. En vardera representant från Stockholm Visitor Board och Destination Sigtuna har intervjuats. Även personer från den akademiska världen har kommit tills tals för att ge sin syn på sociala medier både generellt men även som ett marknadsföringsverktyg. Utifrån intervjuerna så har författarna kommit fram till att både Stockholm Visitor Board och Destination Sigtuna vill och strävar efter att ha en personlig kontakt via sociala medier med sina besökare. Detta är dock något som de inte lyckats med anser författarna. Närmast att lyckas kommer Destination Sigtuna. Då båda är mitt uppe i en ny satsning kring sociala medier så kommer det troligtvis ske stora förändringar när det gäller sociala medier för båda dessa företag. Det författarna menar är att dessa två använder sociala medier likt ett traditionellt sätt att marknadsföra sig, något som det inte är skapat för. Sociala medier ska inbringa till kommunikation mellan människor, både som företag till kund men även från människa till människa. Fördelarna med att marknadsföra sig via sociala medier är att det är ett billigt och enkelt att göra det. Det tar inte mycket av din tid och det kostar inte speciellt mycket. Men det krävs att man marknadsför sig på rätt sätt, annars kan det stjälpa mer än hjälpa. Nackdelarna är då att, som sagt, man gör det på rätt sätt. Att vara närvarande via sociala medier är viktigt, annars kan man inte svara på det som sägs om ens företag. / This study has as purpose to analyze how two destination management companies reflect on social media. The two companies are Stockholm Visitor Board and Destination Sigtuna. The authors also want to analyze how they market themselves via social media and what the advantages and downsides of such marketing strategy may be. By using a qualitative research point with several interviews, the authors wanted to come with an answer to the purpose of this study. The authors came to the conclusion that neither Stockholm Visitor Board nor Destination Sigtuna uses social media as the media is attended to do. They talk about having a personal level of communication, but they do not pursue it. This is something that probably will change do to that both are in a reorganization within the social media aspect. The advantages of marketing via social media are many. It’s a cheap and easy way to market your company. And if you do it right, it will save you a lot of money. The downside is the absent from social media. If your company isn’t on social media and talk to the costumers, it can be quite expensive in the long run.

Habilitacijos procedūrai teikiamoje mokslo darbų apžvalgoje apibendrinama Vilniaus universiteto Širdies ir kraujagyslių ligų klinikoje taikyto sunkaus širdies nepakankamumo gydymo patirtis. Įrodytas intraaortinės kontrapulsacijos balionėliu taikymo tikslingumas pacientams su dekompensuota dilatacine kardiomiopatija. Įvertintas dirbtinių skilvelių, kaip tilto į transplantaciją ar likimo terapiją efektyvumas. Nustatyta, kaip techniniai dirbtinių skilvelių pakeitimai gali daryti įtaką gydymo rezultatams. Ištirtas dirbtinių skilvelių poveikis recipiento imuninei sistemai prieš ir po transplantacijos. Apžvelgti alternatyvūs širdies transplantacijai chirurginiai gydymo metodai. Pasiūlyta originali modifikuotos labirinto operacijos technika, įvertintas jos saugumas, efektyvumas ir galimybė derinti su kitomis širdies operacijomis. Prognozuojamos ateities tendencijos labai sunkiam širdies nepakankamumui gydyti. Šiame darbe remiamasi kartu su bendraautoriais atliktų tyrimų 2001-2009 m. rezultatais. Autorius visuose apžvelgiamuose tyrimuose dalyvavo tiesiogiai, kaip padalinio, kuriame gydomi pacientai su labai sunkiu širdies nepakankamumu, vadovas ir kaip chirurgas. Remiantis publikuota medžiaga buvo daryti pranešimai ir Lietuvoje, ir užsienyje. / The experience of treatment of end-stage heart failure cumulated at Vilnius University Cardiovascular Surgery Clinic is provided for habilitation procedure. The experience of intraaortic balloon counterpulsation for the patients suffering from decompensated dilatative cardiomyopathy has been proven. The efficacy of artificial ventricular assist devices as a bridge to transplantation or destination therapy has been evaluated. The role of technical modifications of ventricular assist devices for the outcomes of treatment has been assessed. The impact of assist devices on the immune status of the patient pre- and post-transplantation has also been evaluated. The alternative methods of treatment instead of heart transplantation are reviewed. The original technique of modified maze procedure is proposed; the safety, efficacy and possibilities of combining this technique with other heart operations are assessed. The future trends for treatment of end-stage heart failure are predicted. This study is based on the investigations performed with co-authors during the period since 2001 to 2009. The author has participated directly in all reviewed investigations as the head of the department where patients suffering from end-stage heart failure are being treated and as well as a surgeon. The reports based on the published material have been presented in Lithuania and abroad.