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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
491

Contribution à l'optimisation de la productivité d'un terminal à conteneurs : développement d'un modèle participatif et application aux terminaux de la rangée Hambourg-Le Havre

Ludoluka, Kiala 11 June 2007 (has links)
La thèse a étudiée en profondeur la problématique de gestion dun terminal à conteneurs. Utilisant tour à tour des techniques de simulation, des visites des terminaux (portuaires, intérieurs et secs) et des discussions avec les acteurs de la logistique en général, une définition de la gestion dun terminal à conteneurs est établie et les paramètres fonctionnels du terminal sont précisés. Partant des conclusions tirées des résultats des simulations des scenarios conçus et testés selon une méthodologie scientifique validée par des acteurs de la chaîne logistique de transport et des experts de la conteneurisation, la thèse établit que loptimisation de la gestion dun terminal à conteneurs ne doit plus être pensée en prenant le terminal comme étant un acteur isolé dans la chaîne logistique, mais plutôt comme faisant partie dun ensemble logistique quil faut optimiser de façon intégrée. La thèse introduit ainsi la théorie de la modélisation dans la chaîne logistique. Deux modèles sont identifiés dont le premier décrit le fonctionnement actuel de la chaîne logistique: Le modèle Client, et un nouveau modèle ou un nouveau mode de fonctionnement visant une logistique intégrée: Le modèle participatif. La thèse propose ensuite une plate forme des données logistiques spécialement conçue selon le modèle participatif. Testés avec des données des terminaux de la rangée Hambourg Le Havre, les résultats montrent quil est possible de réduire de 50% le temps de séjour des conteneurs aux terminaux maritimes avec comme conséquence une réduction dans les mêmes proportions de la congestion dans ces terminaux. Autres conclusions intéressantes: la réduction du temps passé par les moyens de transport de pré et post acheminement des conteneurs dans les ports, une meilleure utilisation des plates formes logistiques grâce à une meilleure programmation des activités de transport, une réduction des émissions de CO2 et une réduction de la congestion aux abords des plates formes logistiques et des ports. Finalement, la thèse montre quune intermodalité bien réfléchie est une source de croissance de la productivité et des revenus de tous les acteurs impliqués dans la chaîne de transport intermodal.
492

Placering av lastbärare : Faktorer som styr placeringen av lastbärare i terminal

Sahlin, Sofia January 2009 (has links)
Purpose: The Essay is written on behalf of a company called ”Uppdragsgivaren”. The purpose is to connect theory with the result of the survey and thereby find the critical factors for an optimal placement of the cargo holders in the company’s terminal.       Method: A qualitative case study has been carried out. The theory collection is completed with the result from the survey, which include the information “Uppdragsgivaren“ provides and the result from the survey. The survey is completed with telephone interviews. The survey is sent to seven persons working on similar company as “Uppdragsgivaren”. The study has a combination between the positivistic and hermeneutic view. The result is treated deductive. Theory and empirical are connected and among several theories one is chosen and will be tested on the company. Recommendations are given to “Uppdragsgivaren” and so are suggestions on further studies.   Result: The test shows that one part of the model is possible for “Uppdragsgivaren” to use when they want to optimize the cargo holder terminal. Part one of the tested model is independent from frequency and volume, and is therefore not applicable. Part two is applicable and the cargo holders can be arranged based on their volume. The result is thus that the most frequent cargo holder shall be placed on the most accessible area.
493

Intermodal Transport Cost Model and Intermodal Distribution in Urban Freight

Kordnejad, Behzad January 2013 (has links)
This study aims to model a regional rail based intermodal transport system and to examine the feasibility of it through a case study for a shipper of daily consumables distributing in an urban area and to evaluate it regarding cost and emissions. The idea of an intermodal line train is that of making intermediate stops along the route thus enabling the coverage of a larger market area than conventional intermodal services, hence reducing the high cost associated with feeder transports, the congestion on the road network and generated externalities. The results of the case study indicate that the most critical parameters for the feasibility of such a system are the loading space utilization of the train and the cost for terminal handling. / <p>QC 20130531</p> / Regional kombitransportsystem i Mälardalen
494

Mechanisms of High Glucose-induced Decrease in β-cell Function

Tang, Christine 23 February 2011 (has links)
Chronic hyperglycemia, a hallmark of type 2 diabetes, can decrease β-cell function and mass (β-cell glucotoxicity); however, the mechanisms are incompletely understood. The objective was to examine the mechanisms of β-cell glucotoxicity using in vivo and ex vivo models. The hypothesis is that oxidative stress plays a causal role in high glucose-induced β-cell dysfunction in vivo via pathways that involve endoplasmic reticulum (ER) stress and JNK. The model of β-cell glucotoxicity was achieved by prolonged i.v. glucose infusion (to achieve hyperglycemia). In Study 1, 48h glucose infusion increased total and mitochondrial superoxide levels in islets, and impaired β-cell function in vivo and ex vivo. Co-infusion of the superoxide dismutase mimetic Tempol decreased total and mitochondrial superoxide, and prevented high glucose-induced β-cell dysfunction in vivo and ex vivo. These results suggest that increased superoxide generation plays a role in β-cell glucotoxicity. In Study 2, 48h glucose infusion increased activation of the unfolded protein response (XBP-1 mRNA splicing and phospho-eIF2α levels). This was partially prevented by Tempol. Co-infusion of the chemical chaperone 4-phenylbutyrate with glucose decreased spliced XBP-1 levels, and prevented high glucose-induced β-cell dysfunction in vivo and ex vivo. Co-infusion of 4-phenylbutyrate also decreased total and mitochondrial superoxide induced by high glucose. These results suggest that 1) ER stress plays a causal role in high glucose-induced β-cell dysfunction, and 2) there is a link between oxidative stress and ER stress in high glucose-induced β-cell dysfunction in vivo. In Study 3, JNK inhibition using the inhibitor SP600125 in rats or JNK-1 null mice prevented high glucose-induced β-cell dysfunction ex vivo and in vivo. SP600125 prevented high-glucose-induced β-cell dysfunction without decreasing total and mitochondrial superoxide levels. Both Tempol and 4-phenylbutyrate prevented JNK activation induced by high glucose. These results suggest a role of JNK activation in high glucose-induced β-cell dysfunction downstream of increased superoxide generation and ER stress in vivo. Together, the results suggest that 1) oxidative stress, ER stress and JNK activation are causally involved in β-cell glucotoxicity, and 2) High glucose-induced oxidative stress and ER stress are linked, and both impair β-cell dysfunction via JNK activation in vivo.
495

Characterization of SecA N-Terminus for Membrane Binding and Activity

Floyd, Jeanetta Holley 30 November 2007 (has links)
SecA is an essential component for the translocation of proteins across bacterial membranes. Though SecA is known to function in the membrane the mechanism for this process remains unclear. In this study we identify two specific regions of SecA that may be important for N-terminal membrane interactions. Molecular modeling of SecA from the E. coli and B. subtilus crystal structures, previously determined, revealed that the first 30 amino acids of SecA consists of a helix of amino acids 1-11 connected by a linker (amino acids 12-16) to an amphipathic helix of amino acids 17-30. The first helix is dispensable for SecA activity; however, deletions in the second N-terminal helix, at amino acids 21-25, result in decrease of SecA activity and a deletion of 26 amino acids no longer complements E. coli ts mutant BL21.19. We show that the deletions of N-terminal amino acids that result in the decrease of SecA activity are correlated to the loss of SecA membrane binding and integration in these deletion mutants. In this study we also test the accuracy of a new membrane protein prediction software PSSM_SVM. This program predicted an embedded membrane (EM) region at SecA amino acids 110-118. The predicted sequence represents an unusual prediction for an EM region as most membrane integral regions consist of 15-30 amino acids. Molecular modeling indicated that the region 110-118 is a part of a helix composed of amino acids 107-121 in E. coli SecA, and is indicative of a membrane embedded domain. Site-directed mutagenesis was carried out with several conserved residues, which included L110, L114, and L118 to determine if substitutions at these positions would affect SecA activity. Our data shows that most SecA mutants (including some predicted to be inactive) are active in vivo; however, L110E and L114R mutations rendered the mutated SecA non-functional. All together this study shows that the N-terminal limit of SecA resides at amino acid 26 and that amino acids 21-25 may form a N-terminal membrane binding determinate. Moreover, the predicted EM region may indeed correspond to a functional embedded membrane region for SecA.
496

A comparison between the Semantic Differential Scale for Assessing Patient Feelings and the Tennessee Self Concept Scale

Hadley, Sue A. 03 June 2011 (has links)
Ball State University LibrariesLibrary services and resources for knowledge buildingMasters ThesesThere is no abstract available for this thesis.
497

Mechanisms of High Glucose-induced Decrease in β-cell Function

Tang, Christine 23 February 2011 (has links)
Chronic hyperglycemia, a hallmark of type 2 diabetes, can decrease β-cell function and mass (β-cell glucotoxicity); however, the mechanisms are incompletely understood. The objective was to examine the mechanisms of β-cell glucotoxicity using in vivo and ex vivo models. The hypothesis is that oxidative stress plays a causal role in high glucose-induced β-cell dysfunction in vivo via pathways that involve endoplasmic reticulum (ER) stress and JNK. The model of β-cell glucotoxicity was achieved by prolonged i.v. glucose infusion (to achieve hyperglycemia). In Study 1, 48h glucose infusion increased total and mitochondrial superoxide levels in islets, and impaired β-cell function in vivo and ex vivo. Co-infusion of the superoxide dismutase mimetic Tempol decreased total and mitochondrial superoxide, and prevented high glucose-induced β-cell dysfunction in vivo and ex vivo. These results suggest that increased superoxide generation plays a role in β-cell glucotoxicity. In Study 2, 48h glucose infusion increased activation of the unfolded protein response (XBP-1 mRNA splicing and phospho-eIF2α levels). This was partially prevented by Tempol. Co-infusion of the chemical chaperone 4-phenylbutyrate with glucose decreased spliced XBP-1 levels, and prevented high glucose-induced β-cell dysfunction in vivo and ex vivo. Co-infusion of 4-phenylbutyrate also decreased total and mitochondrial superoxide induced by high glucose. These results suggest that 1) ER stress plays a causal role in high glucose-induced β-cell dysfunction, and 2) there is a link between oxidative stress and ER stress in high glucose-induced β-cell dysfunction in vivo. In Study 3, JNK inhibition using the inhibitor SP600125 in rats or JNK-1 null mice prevented high glucose-induced β-cell dysfunction ex vivo and in vivo. SP600125 prevented high-glucose-induced β-cell dysfunction without decreasing total and mitochondrial superoxide levels. Both Tempol and 4-phenylbutyrate prevented JNK activation induced by high glucose. These results suggest a role of JNK activation in high glucose-induced β-cell dysfunction downstream of increased superoxide generation and ER stress in vivo. Together, the results suggest that 1) oxidative stress, ER stress and JNK activation are causally involved in β-cell glucotoxicity, and 2) High glucose-induced oxidative stress and ER stress are linked, and both impair β-cell dysfunction via JNK activation in vivo.
498

COCONUT 創新專案 – 以網路交易為基礎的金融創新專案 / COCONUT INNOVATION- FINANCIAL INNOVATION BASED ON THE CASH TRANSACTIONS

Volha Hutsava, Volha Hutsava Unknown Date (has links)
The thesis is aimed to propose a financial innovation called COCONUT payment system. This innovative payment system is based on a combination of the cash and electronic money, presented as an ATM-like machine for purchase and payment execution, and operated via an electronic account, which allows its users to operate as a credit cards owner. This study commences with a review of the current major payment systems in the United States, followed by an analysis of the strength and weakness of these systems, and then proposes a payment system that combines the most popular two: cash and credit card with a healthier mechanism on financial control to both avoid the recurrence of financial crisis caused by credit crush and keep the current benefits. The COCOCNUT system can be applied not onbly to the market of the USA, but BRIC, developing and under seveloped countries’ market, those regions where cash remains the major payment way. As for the feasibility and the probability of promoting and applying this new system to replace the current systems or to implement in the new markets, the proposed COCONUT payment system, takes into consideration the differences of markets and regional regulations. The COCONUT project also provides trial calculations of its value proposition from the perspective of the project realization.
499

Terminal Gothenburg North - A posssible dry port? / Terminal Göteborg Norra - En möjlig Dry port?

Bergman, Johan, Larsén, Henrik January 2013 (has links)
Green Cargo driver idag ett antal terminaler i Sverige i syfte att främja transporter på järnväg och ser möjligheter i att utveckla en av sina terminaler i Göteborg, Göteborg Norra, till en så kallad dry port, alltså en intermodal terminal i inlandet. Detta gav upphov till projektet Terminal Göteborg Norra – en möjlig dry port? med målet att undersöka potentialen och omställningarna med att utveckla befintligt kunderbjudande på Göteborg Norra genom att utreda konceptet dry port samt undersöka efterfrågan på marknaden. Syftet med en dry port är att fungera som en förlängning av hamnen och bör enligt forskare erbjuda samma servicetjänster som en hamn, det vill säga förtullning, säker lagring av både lastade och tomma containrar samt underhåll och städning av containrar. En dry port kan ses som ett bra komplement till hamnar som ligger inne i städer och har problem med begränsade utrymmen i hamnområdet och svårt att expandera då ytan inte längre räcker till. Dessutom kan man minska utsläppen av CO2 genom att få mer gods transporterat på järnvägen. Att utveckla Göteborg Norra, som Green Cargo idag driver i egen regi, skulle innebära att befintliga tjänster behöver kompletteras med de tjänster som fullbordar en dry port. Projektet resulterade i en utredning med potentiella intäkter och kostnader som förväntas uppstå vid ett utvecklande av Göteborg Norra till en dry port. Det visade sig att kostnaderna med att utveckla Göteborg Norra till en dry port är fullt möjliga att tjäna in inom den bestämda tidsramen på två år. Trots det så anser projektet att det finns många delar i utvecklandet som talar emot ett fulländat dry port koncept på Göteborg Norra. Då projektet anser att terminalens läge inte är optimalt för en dry port och att det finns begränsade lagringmöjligheter, oklarheter gällande tulltjänster samt att hamnen inte visar något intresse för att utnyttja tjänsten så är det svårt att motivera omställningen till en fulländad dry port. Däremot finns det en del i dry port konceptet som projektet ser positivt till och det skulle innebära att Göteborg Norra tar emot lastade containrar för transport till hamnen. Då projektets marknadsundersökning visade att många speditörer anser att det är problem med långa köer för att hämta och lämna gods i Göteborgs hamn så skulle Green Cargo kunna erbjuda en tjänst där dessa kunder kan åka till Göteborg Norra och lämna eller hämta sitt gods. Detta under förutsättning att Green Cargo kan erbjuda en billigare lösning och att det inte uppstår köer i trafiken runt terminalen. Klarar Green Cargo detta har de ett bra argument som borde locka både speditörer och Göteborgs hamn att nappa på lösningen.
500

Performance of passive long term investments : A longitudinal study over the relative performance of emerging- and developed markets

Babar, Haseeb Zaman, Norberg, Johan January 2013 (has links)
The concept of emerging markets came to surface in early 1980 and constituted of only eight countries from the two continents of South America and Asia. The globalization of financial markets has since raised the importance of emerging capital markets. We take a quantitative approach to investigate the performance of emerging markets compared to developed markets. The aim of the study is to conclude if emerging markets offers investment value and if logic in portfolio theory can be used to improve the chance of creating a relatively better performing investment. Included markets in our study are Brazil, Russia, India, China, Colombia, Indonesia, Vietnam, Egypt, Turkey and South Africa. S&amp;P 500 is our benchmark for developed market performance. Sample period is 2002-01-01 to 2011-12-31 and monthly return data, creating 120 data points on each index.   The weighting schemes used for the portfolios are min variance optimization, geographical location and high and low correlation. All investments are scored on performances in correlation to S&amp;P 500, inflation adjusted growth, currency effect, Sharpe ratio, skewness and kurtosis. Rankings are done on the separate categories, on the individual overall ranking on only countries and one overall ranking on all investments. A brief overview of the overall ranking for all investments suggest that medium performing investments are overrepresented (12/20) and the low and high is underrepresented (3/20 and 5/20). Of note is that the min variance portfolio outperforms its components, the geographical portfolios have a wide range and the high correlated portfolio outperforms the low. The country to portfolio ratio over each grade suggests only a small skew of the results. There is no low scoring portfolio but the other two ratios are close to 50/50, suggesting that on average the portfolios create diversification benefits. Furthermore normality of returns seem to be violated and then the concept of volatility as a risk measure is significantly impaired also currency risk can be of high importance, currency effects ranged from -48% to 28.7%. Assuming non-normality seems more accurate than assuming normality; therefore we need to improve on volatility as a tool to measure risk. So one direction for further research we see a need is in the concept of volatility. The initial reason for this research came from small investors’ seemingly intuitive knowledge that emerging markets are a suitable investment option. We have concluded that they in fact are, therefore we suggest that a qualitative study is conducted to investigate this seemingly natural intuition.

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