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1

Defendini, Hélène. "Bases génétiques et conséquences évolutives de la perte de sexe dans le groupe des pucerons". Electronic Thesis or Diss., Rennes, Agrocampus Ouest, 2023. http://www.theses.fr/2023NSARA094.

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La reproduction sexuée est considérée comme le mode de reproduction ancestral des eucaryotes, mais elle été perdue à plusieurs reprises dans de nombreux taxons. Comprendre les mécanismes par lesquels les lignées asexuées apparaissent et persistent dans le temps reste un défi majeur de la biologie évolutive. Au cours de ma thèse, j'ai étudié les bases génétiques ainsi que les conséquences évolutives de la perte du sexe chez les pucerons, un groupe qui présente un polymorphisme de reproduction. Le mode de reproduction ancestral des pucerons est la parthénogenèse cyclique (CP, une alternance de plusieurs générations parthénogénétiques et d'une génération sexuée), mais la parthénogenèse obligatoire (OP) est fréquemment observée dans ce groupe. Les lignées OP dérivées ne sont pas capables de produire des femelles sexuées bien qu'elles conservent souvent la capacité de produire des mâles. Pour caractériser les régions génomiques impliquées dans la transition de la reproduction CP à OP, nous avons utilisé des approches de scan génomique sur différents taxons de pucerons plus ou moins proches génétiquement et présentant des variations de mode de reproduction. Nous avons montré que la base génétique de la perte du sexe est différente entre les taxons étudiés, sans convergence apparente dans le contenu génique ou les fonctions des gènes. Ainsi, plusieurs régions génomiques indépendantes peuvent être responsables de la perte du sexe chez les pucerons, ce qui suggère qu'il existe de nombreuses voies menant à l'asexualité dans ce groupe. Ensuite, nous avons étudié les conséquences évolutives de la perte du sexe sur les traits et les gènes essentiels à la reproduction sexuée. Comme il est peu probable que les mâles produits par les lignées OP transmettent leurs gènes (les lignées CP étant généralement séparées géographiquement des lignées OP), nous avons testé la prédiction selon laquelle les traits mâles dégénèrent. La production de mâles était en effet réduite dans les lignées OP, supposément en raison de la contre-sélection, mais le succès reproductif des mâles n'était que légèrement inférieur à celui des lignées CP, probablement en raison de la sélection relâchée qui agit lentement ou d’opportunités reproductives sous-estimées. Comme les lignées OP produisent rarement des mâles et ne produisent pas de femelles sexuées, l'expression génétique des femelles parthénogénétiques n'est plus contrainte par celle des autres morphes. Nous avons donc prédit que la disparition du conflit sexuel (qui survient lorsqu'il existe différents optima spécifiques à chaque morphe pour un trait partagé par différents morphes) entraînerait des changements d’expression des gènes. Nous avons donc comparé les profils d'expression génétique des lignées CP et OP pour différents morphes du puceron du pois. Nous avons observé que l'expression des gènes chez les mâles des lignées OP tendait vers l'optimum des femelles parthénogénétiques, comme le prévoyait la théorie. Plus surprenant, les mâles et les femelles parthénogénétiques des lignées OP surexpriment systématiquement des gènes exprimés dans les gonades des morphes sexués. Ces changements dans l'expression des gènes dans les lignées OP peuvent s’expliquer par un relâchement de la sélection ou la reconversion de réseaux de gènes autrement utilisés dans les lignées sexuées. Cette thèse illustre la pertinence de l'utilisation d'espèces aux systèmes de reproduction polymorphes pour comprendre l'histoire évolutive de la perte du sexe et ses conséquences
Sexual reproduction is considered the ancestral reproductive mode of eukaryotes, yet it has been lost several times in many taxa. Understanding the mechanisms by which asexual lineages appear and persist over time remains a major challenge of evolutionary biology. During my PhD, I investigated the genetic basis as well as the evolutionary consequences of sex loss in aphids, a group that displays reproductive polymorphism. The ancestral reproductive mode of aphids is cyclical parthenogenesis (CP, an alternation of several parthenogenetic generations and one sexual generation), but obligate parthenogenesis (OP) is frequently observed in this group. Derived OP lineages are not able to produce sexual females though they often retain the ability to produce males. First, to characterize genomic regions involved in the transition from CP to OP reproductive mode, we used genome scan approaches on different aphid taxa that are more or less genetically related and exhibit variation in reproductive mode. We showed that the genetic basis of sex loss is different between the studied taxa, with no apparent convergence in gene content norfunctions. Thus, several independent genomic regions may be responsible for sex loss in aphids, suggesting that there are many paths that lead to asexuality in this group. Second, we studied the evolutionary consequences of the loss of sex on traits and genes essential for sexual reproduction. Since the males produced by OP lineages are unlikely to pass on their genes (because CP lineages are usually separated from OP ones), we tested the prediction that male traits should degenerate. Male production was indeed reduced in OP lineages, supposedly resulting from counter-selection, but male reproductive success was only slightly lower than in CP lineages, presumably due to the slow action of relaxed selection orunderestimation of reproductive opportunities. As OP lineages produce rare males and also do not produce sexual females, the gene expression of parthenogenetic females in these OP lineages is no longer constrained by that of other morphs. We thus predicted that the disappearance of sexual conflict (which arises when there are different morph-specific optima for a trait shared by different morphs) would result in shifts of gene expression. We therefore compared gene expression patterns of CP and OP lineages for different morphs in the pea aphid. We observed that gene expression in males from OP lineages tended towards the parthenogenetic female optimum, as predicted by theory. More surprisingly, males and parthenogenetic females of OP lineages consistently over-expressed genes typically expressed in the gonads of sexual morphs. These changes in gene expression in OP lineages may arise from the relaxation of selection or the repurposing of gene networks otherwise used in sexual lineages. This thesis illustrates the relevance of using species with polymorphic reproductive systems to understand the evolutionary history of sex loss and its consequences
2

Minbashi, Niloofar. "Applying Data Analytics to Freight Train Delays in Shunting Yards". Licentiate thesis, KTH, Transportplanering, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-284672.

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The European Commission has foreseen a modal share of 30% by 2030 for rail freight transport. To achieve this increase in the modal share, enhanced reliability of rail freight services is required. Optimal functioning of shunting yards is one of the areas that can improve this reliability. Shunting yards are large areas allocated to reassemble freight trains for dispatching to new destinations. Their productivity has a direct impact on the overall performance of a rail freight network. Therefore, analysing and modelling of departure deviations from shunting yards are required to enhance the interactions between shunting yards and the network; this thesis contributes to this gap. Paper I investigates the probability and temporal distribution of departure deviations using a large data set comprising 250,000 departures over seven years from two main shunting yards (Malmö and Hallsberg) in Sweden. The probability distribution of departure deviations is found comparing four main distributions including the exponential, the log-normal, the gamma, and the Weibull according to the maximum likelihood estimates and the results of the Anderson-Darling goodness of fit test.  The log-normal and the gamma are shown the best fits for departure deviations: the former on delays, and the latter on early departures. In the temporal delay distribution, the weekly and monthly, but not yearly delayed departures are positively correlated with the network usage. However, for hourly delayed departures, a shunting yard involved with international traffic does not show any correlation between delayed departures and the network usage, whereas a domestic shunting yard shows a significant negative correlation between these two parameters.  The findings obtained from this thesis contribute to a better understanding of departure deviations from shunting yards, and can be applied in enhancing the operations and capacity utilization of shunting yards in future models. Papers II and III analyse the relationship between congestion in the arrival yard and departure delays using the same data set as paper I.  According to previous research, congestion plays an important role in shunting yard delays. With defining congestion as the number of arriving trains before departure time, paper II analyses this relationship limiting the arrivals and departures between the two shunting yards considering varying time periods before departure,whereas Paper III elaborates the analysis by defining congestion level in a fixed period of time before departure time including all arrivals and departures. Considering the data set used in the analysis, the results show that there is no significant relationship between the congestion in the arrival yard and departure delays of trains. It is possible that congestion may not impact the departure delays of trains, but it may impact the departure delays of wagons due to missed wagon connection or increasing wagon idle time, which can be explored with the availability of wagon connection data.  Additionally, future elaboration of congestion definition, covering congestion at the shunting yard level, may lead to further improved analyses.
Europeiska kommissionen har förutspått en markansandel på 30% framtill 2030 för järnvägstransporter av gods. För att uppnå denna ökning krävsökad tillförlitlighet hos järnvägstransporttjänster. Rangergodsbangårdars optimalafunktion är ett av de områden som kan förbättra denna tillförlitlighet.Rangergodsbangårdar stora områden som är avsedda för att koppla ihopgodståg för sändning till nya destinationer. Deras produktivitet har en direktinverkan på järnvägsnätets totala prestanda. Därför krävs analys och modelleringav avvikelser från dessa noder för att förbättra interaktionen mellanrangergodsbangårdar och järnvägsnätet. I papper I undersöks sannolikheten och den tidsmässiga fördelningen avavvikelser med hjälp av en stor datamängd som omfattar 250 000 avgångaröver sju år från två rangergodsbangårdar (Malmö och Hallsberg) i Sverige.Sannolikhetsdistributioner av avvikelser jämförs med fyra huvuddistributioner,exponentiell, log-normal, gamma och Weibull enligt de maximalasannolikhetsuppskattningarna och resultaten av Anderson-Darling godhetav passningstest. Log-normal och gamma visar sig passa bäst för avvikelser:den förstnämnda vid förseningar och den senare vid tidiga avgångar. I dentidsmässiga fördröjningsfördelningen är de veckovisa och månatliga men inteårliga försenade avgångarna positivt korrelerade med järnvägsnätets nyttjandegrad.För försenade avgångar per timme visar dock en rangergodsbangårdsom är inblandad i internationell trafik ingen korrelation mellan försenadeavgångar och järnvägsnätets nyttjandegrad, medan en inhemsk rangergodsbangårdvisaren signifikant negativ korrelation mellan dessa två parametrar.Resultaten från denna avhandling bidrar till en bättre förståelse av avvikelserfrån rangergodsbangårdar och kan användas för att förbättra drift och kapacitetsutnyttjandeav rangergodsbangårdar växelplatser i framtida modeller. Papper II och III analyserar förhållandet mellan trängsel i ankomstgårdenoch avgångsförseningar med hjälp av samma datamängd som i papperI. Enligt tidigare analyser spelar trängsel en viktig roll vid förseningar förrangergodsbangårdar. Trängsel definieras som antalet ankommande tåg föreavgångstid och papper II analyserar detta förhållande som begränsar ankomsteroch avgångar mellan de två rangergodsbangårdar med beaktande av olikatidsperioder före avgång, medan papper III utvecklar analysen genom attdefiniera trängselnivån under en fast tidsperiod före avgångstid inklusive allaankomster och avgångar. Med tanke på datamängden som användes i analysenvisar resultaten att det inte finns något signifikant samband mellan trängselni ankomstgården och tågens förseningar. Det är möjligt att trängsel kanskeinte påverkar tågens avgångsfördröjningar, men det kan påverka vagnarnasavgångsfördröjningar på grund av missad vagnanslutning eller öka vagnenstomgångstid, vilket kan undersökas med vid tillgång av vagnanslutningsdata.Dessutom kan framtida vidareutveckling av definitionen av trängsel som påen detaljerad nivå täcker rangergodsbangårdars alla delar, leda till ytterligareförbättrade analyser.

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3

Sundqvist, Frej. "Developing Markov chain models for train delay evolution in winter climate". Thesis, Umeå universitet, Institutionen för fysik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-179526.

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The traffic on Swedish railways is increasing and punctuality is of important matter for both passenger and freight trains. The problem of modeling train delay evolution is complex since conflicts between trains can occur and since a delay can have a wide variety of causes. Swedish railways faces in addition harsh winter climate. Studies of railways in Scandinavia have shown that harsh winter climate decreases the punctuality of trains. This thesis work investigates the possibilities of modeling train delay evolution as continuous time Markov processes and which specific modeling choices are preferable. It also further assesses the impact of a harsh winter climate on the delay evolution. The studied segments are Stockholm - Umeå and Luleå - Kiruna. Both over one winter season. It was found that a change in the time schedule, which in a way redefines the delay, allows for a better fit and better prediction capabilities. It reduced the MSE of the prediction by 50 %. As for the weather variables, four variables were included together with their week long moving averages. Low temperatures were found to increase the risk of a delay (Hazard ratio of 1.10) as well as to decrease the chance of recovering from a delay (Hazard ratio of 0.91). No other significant weather impacts were found.
4

Fakhraei, Roudsari Farzad. "Spatial, temporal and size distribution of freight train time delay in Sweden". Thesis, KTH, Trafik och logistik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-59708.

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Delays and cancelled trains are often described as a problem for companies that transport goods by rail. Lack of reliability of freight trains is seen as a disadvantage compared to other modes. To date there has been limited quantitative information in Sweden about the size and the structure of the problem of trains not arriving in time. In this thesis information for two years, 2008 and 2009 is available that enable us to do the analysis of distribution on a spatial, temporal and seize-frequency scale. Since the spatial and frequency-size distributions describe the vulnerability of a transport network it has potentially important policy implications. In the size-frequency scale, we analyzed different distribution to fit with the arrival delay at the final station and we conclude that, it is not possible to find a distribution for the whole range of observations. However, considering the tail of arrival delays we find that it is exponentially distributed. This implies that the tail makes up the biggest part of total delay time. The 20 % largest delays contribute to about 78% of total delay minutes. In the spatial scale, we defined stations which have the highest value of arrival delay in the whole network and ranked them. We found out that more than 50% of the total arrival delay per year occurs in just 7% of stations. With the help of regression analysis we analyze how delays are propagated in the network. We find that delays at the origin increase arrival delay but that some part of the initial delay is gained at arrival, probably due to large slack in the time tables. Finally, in the temporal scale we analyzed arrival delays in different time scales such as monthly, weekly and daily delays. We expected that the reduction of the total number of trains in 2009 would reduce not only total but also the average arrival delay since there would be more free capacity. The data shows however, that the average delay did not decrease as the number of trains decreased due to the economic contraction in 2009, indicating that capacity might not be as crucial for explaining delays as previously expected.
5

Karthikeyan, Arun Kumar, e Praveen Kumar Mani. "Visual and Analytical Support for Real-time Evaluation of Railway Traffic Re-scheduling Alternatives During Disturbances". Thesis, Blekinge Tekniska Högskola, Sektionen för datavetenskap och kommunikation, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-4299.

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Disturbances in the railway network are frequent and to some extent, inevitable. When this happens, the traffic dispatchers need to re-schedule the train traffic and there is a need for decision support in this process. One purpose of such a decision support system would be to visualize the relevant, alternative re-scheduling solutions and benchmark them based on a set of relevant train traffic attributes which quantify the effects of each solution. Currently, there are two research projects financed by the Swedish Transport Administration (i.e. Trafikverket) which focus on developing decision support to assist the Swedish train traffic managers: The STEG project and the EOT project. Within the STEG project, researchers at Uppsala University in co-operation with Trafikverket are developing a graphical user interface (referred to as the STEG graph). Within the EOT project, researchers at Blekinge Institute of Technology (BTH) are developing fast re-scheduling algorithms to propose to the Swedish train traffic dispatchers a set of relevant re-scheduling alternatives when disturbances occur. However, neither the STEG graph nor the EOT algorithms are at this point designed to evaluate, benchmark and visualize the alternative re-scheduling solutions. The main objective of this work is therefore to identify and analyze different train traffic attributes and how to use the selected relevant ones for benchmarking re-scheduling solutions. This involves enhancing an existing visual tool (EOT GUI) and using this extended version (referred to as the EOT GUI+) to demonstrate and evaluate the benchmarking of different re-scheduling solutions based on the selected train traffic attributes. The train traffic attributes found in the literature (foremost research publications and documents by Trafikverket) were collected and analyzed. A subset of the most commonly used attributes found were then selected and their applicability in benchmarking re-scheduling solutions for the Swedish train traffic system was further analyzed. The formulas for calculating each of the attribute values were either found in the literature and possibly modified, or defined within this thesis project. In order to assess the use of the attributes for benchmark solutions, experiments were conducted using the enhanced visual tool EOT GUI+ and a set of sample solutions for three different disturbance scenarios provided by the EOT project. The tool only performs a benchmark of two solutions at a time (i.e. a pair wise benchmark) and computes the attribute values for the chosen attributes. The literature review and attribute analysis resulted in a first set of ten different attributes to use including e.g. total final delay (with a delay threshold value of 1 and 5 minutes respectively), maximum delay, total accumulated delay, total delay cost, number of delayed trains and robustness. The formulas to compute these attribute values were implemented and applied to the sample solutions in the experiments. The first phase of the experiments showed that in one of the disturbance scenarios, some of the attribute values were in conflict and that none of re-scheduling solution was dominating the others. This observation led to that the set of attributes needed to be narrowed down and internally prioritized. Based on the experimental results and the analysis of what the research community and the main stakeholder (i.e. Trafikverket) consider are the most important attributes in this context, the final set of attributes to use includes average final delay, maximum delay of a single train, total number of delayed trains and robustness. The contribution of this thesis is primarily the review and analysis of what attributes to use when performing a benchmark of re-scheduling solutions in real-time train traffic disturbance management. Furthermore, this thesis also contributes by performing an experimental assessment of how the attributes and their formulas could work in a pair-wise, quantitative benchmark for a set of disturbance scenarios and which issues that may occur due to conflicting objectives and attribute values. Concerning the enhancement of the visual tool and the visualization of the re-scheduling solutions, the experimental evaluation and analysis shows that the tool would not fit directly to the needs of the train dispatchers. This work should therefore only be seen as a starting point for the researchers whom are working with the development of decision support systems in this context. Furthermore, several iterative experiments have been conducted to select the appropriate attributes for benchmarking solutions and suggesting the best re-scheduling solution. During the experiments, we have used a limited set of different problem instances (2+2+7) representing three different types of disturbances. The performance of the enhanced visual tool EOT GUI+ and its functionalities should ideally also be analyzed further and improved by experimenting with a larger number of instances, for other parts of the Swedish railway network and in co-operation with the real users, i.e. the dispatchers.
6

Nilsson, Robert, e Kim Henning. "Predictions of train delays using machine learning". Thesis, KTH, Hälsoinformatik och logistik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-230224.

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Train delays occur on a daily basis in the commuter rail of Stockholm. This means that the travellers might become delayed themselves for their particular destination. To find the most accurate method for predicting train delays, the machine learning methods decision tree with and without AdaBoost and neural network were compared with different settings. Neural network achieved the best result when used with 3 layers and 22 neurons in each layer. Its delay predictions had an average error of 122 seconds, compared to the actual delay. It might therefore be the best method for predicting train delays. However the study was very limited in time and more train departure data would need to be collected.
Tågförseningar inträffar dagligen i Stockholms pendeltågstrafik. Det orsakar att resenärerna själva kan bli försenade till deras destinationer. För att hitta den mest träffsäkra metoden för att förutspå tågförseningar jämfördes maskininlärningsmetoderna beslutsträd, med och utan AdaBoost, och artificiella neuronnät med olika inställningar. Det artificiella neuronnätet gav det bästa resultatet när det användes med 3 lager och 22 neuroner i varje lager. Dess förseningsförutsägelse hade ett genomsnittligt fel på 122 sekunder jämfört med den verkliga förseningen. Det kan därför vara den bästa metoden för att förutspå tågförseningar. Den här studien hade dock väldigt begränsat med tid och mer information om tågavgångar hade behövts samlas in.
7

Granlöf, Markus. "A study of the effects of winterclimate and atmospheric icing onhigh-speed passenger trains". Thesis, Umeå universitet, Institutionen för matematik och matematisk statistik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-171868.

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Harsh winter climate causes various problems for both the public andprivate sector in Sweden, especially in the northern part and the railway industryis no exception. This master thesis project covers an investigation of the eects ofthe winter climate and a phenomena called atmospheric icing on the performance ofthe train in a region called the Botnia-Atlantica region. The investigation was donewith data over a short period January-February 2017 with simulated weather datafrom the Weather research and forecast model that was compared with the periodOctober - December 2016. The investigation only included high speed trains.The trains have been analysed based on two dierent performance measurements.The cumulative delay which is the increment in delay over a section and the currentdelay which is the current delay compared to the schedule. Cumulative delaysare investigated with survival analysis and the current delay is investigated with aMulti-state Markov model.The results show that the weather could have an eect on the trains performancewhere the survival analysis detected connection between the weather and cumulativedelays. The Markov model also showed a connection between the weather anddelayed trains including that the presence of atmospheric icing had a negative eecton remaining in a state of non-delay.
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Chin, Elizabeth D. "Symptom Experience and Treatment Delay during Acute Exacerbation of Chronic Obstructive Pulmonary Disease: A Dissertation". eScholarship@UMMS, 2012. https://escholarship.umassmed.edu/gsn_diss/30.

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Chronic obstructive pulmonary disease (COPD) is a major health problem in the United States. Acute exacerbations of COPD are primarily responsible for the physical, psychological and economic burden of this disease. Early identification and treatment of exacerbations is important to improve patient and healthcare outcomes. Little is known about how patients with COPD recognize an impending exacerbation and subsequently decide to seek treatment. The purpose of this qualitative descriptive study was to explore and describe symptom recognition and treatment delay in individuals experiencing an acute exacerbation of chronic obstructive pulmonary disease (COPD). Leventhal’s Common Sense Model of illness representation undergirded this study. Using semi-structured interviews, adults hospitalized with an acute exacerbation of COPD were asked to describe their symptom experience and self care behaviors, including treatment seeking, in the days to weeks prior to hospitalization. Data analysis revealed one main theme: Recognizing, responding and reacting to change, and six subthemes: Something’s coming, Here we go again, Seeking urgent treatment, Riding it out, Not in charge anymore and My last day that richly described the COPD exacerbation experience. The study revealed that patients experience an illness prodrome prior to exacerbation and have a recurrent exacerbation symptom pattern that was self-recognized. Treatment seeking was most influenced by the speed and acuity of exacerbation onset, severity of breathlessness, fears of death, nature of patient-provider relationship and the perception of stigmatization during prior healthcare encounters. These findings are important for the development of interventions to improve patient recognition and management of COPD exacerbations in the future.
9

Newhall, William George. "Wideband Propagation Measurement Results, Simulation Models, and Processing Techniques for a Sliding Correlator Measurement System". Thesis, Virginia Tech, 1997. http://hdl.handle.net/10919/35678.

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Radio wave propagation measurements provide a way to accurately and reliably characterize environments to assist in the development and optimization of wireless communication systems. As digital radio systems occupy wider bandwidths and use multipath signal combining to enhance quality of service, knowledge of time dispersion and the multipath structure of radio channels become increasingly important. The wideband measurement system presented herein provides a practical means to precisely measure the delays and strengths of individual multipath components which arrive at a radio receiver.

Presented in this Thesis are fundamental theory, practical implementation, and simulation models for a sliding correlator measurement system. The sliding correlator technique is explained in detail and large-scale measurement survey is presented. Techniques for statistically quantifying the characteristics of propagation using the sliding correlator measurements are presented and compared. The development of simulations of the sliding correlator system is described, and simulation results are used to test conventional and newly developed post-processing algorithms.

This Thesis presents a practical view of the sliding correlator measurement system, but its foundations are rooted in the theoretical results which are explained and derived herein. Propagation researchers and students in the wireless communication field may find this work and the cited references useful for continued study of wideband propagation measurements or for application of the sliding correlator system as a wideband measurement solution.
Master of Science

10

Oharek, Aleš. "Zvyšování bezpečnosti a výkonnosti navigace dopravních letadel po trati letu". Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2009. http://www.nusl.cz/ntk/nusl-228554.

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Thesis presents description of the air traffic safety, efficiency, capacity and preferences of navigation equipment. Those aspect are further used to suggestion of future advancement airspace, which occur during almost all phases of the flight.
11

Coelho, Mônica Andrigo Moreira de Ulhoa. "Tradução e adaptação transcultural da escala de avaliação da primeira infância para bebês e crianças DECA I/T (Devereux Early Childhood Assessment for Infants And Toddlers)". Pontifícia Universidade Católica de São Paulo, 2017. https://tede2.pucsp.br/handle/handle/20514.

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The subject of this master´s dissertation is related to early childhood and resilience in infants (four weeks to 18 months old) and toddlers (18 to 36 months old). The study aimed at translating into Portuguese and transculturally adapting the early childhood assessment for infants and toddlers named ―Devereux Early Childhood Assessment for Infants and Toddlers‖ (DECA I/T), developed by Gregg Powell, Mary Mackrain and Paul LeBuffe, owned by The Devereux Foundation, edited and published by Kaplan Early Learning Corporation in 2007. DECA I/T assessment measures the social and emotional protective factors (attachment/relationship, initiative and self-regulation) to evaluate and indicate the strength of such factors in infants and toddlers. For the translation and transcultural adaptation of the assessment, the guidelines of Hambleton and Patsula (1998) and Souza and Rojjanasrirat (2010) were generally used. The procedure consisted of the following steps: (a) translation of the original instrument in English into Portuguese by two Brazilian, bilingual, independent translators, being one of them a sworn-translator, both of them familiarized with the Brazilian and American cultures, and without knowledge in Psychology; (b) comparison and consolidation of both translated versions by the researcher, who acted as a third translator, and review of the synthetized version; (c) back-translation of the consolidated version in Portuguese into English by another American, bilingual, independent translator, fluent in Portuguese, familiarized with the Brazilian and American cultures and not working in the Psychology area, followed by review and approval of the final version of the assessment in Portuguese by an Expert Committee; (d) application of the Portuguese final version in a pilot project. The translated DECA I was applied to and responded by 13 evaluators (six mothers, one grandmother, one father and five nursery caregivers of infants). A total of 12 infants were evaluated (one of them was evaluated by the father and the nursery caregiver). The translated DECA T was applied to and responded by 13 evaluators (six mothers, one grandmother, two room assistants, two educators e two teachers of toddlers). A total of 19 toddlers were evaluated (two room assistants evaluated two toddlers each, two educators evaluated three toddlers each, and two teachers evaluated three toddlers each). After application of the pilot project, the translation into Portuguese of DECA I/T was considered culturally adapted and apt for future validation
O tema da dissertação de mestrado é ligado à primeira infância e à resiliência em bebês (de quatro semanas a 18 meses de idade) e crianças (de 18 a 36 meses de idade). O objetivo do trabalho foi traduzir para o português e realizar a adaptação transcultural da escala de avaliação da primeira infância para bebês e crianças denominada Devereux Early Childhood Assessment for Infants and Toddlers (DECA I/T), criada e desenvolvida por Gregg Powell, Mary Mackrain e Paul LeBuffe, detida pela The Devereux Foundation, editada e publicada por Kaplan Early Learning Corporation em 2007. A escala DECA I/T mede os fatores de proteção sociais e emocionais (apego/relacionamento, iniciativa e autorregulação) para avaliar e indicar a força desses fatores em bebês e crianças. Para realização da tradução e adaptação transcultural foram utilizadas, em linhas gerais, as diretrizes e orientações de Hambleton e Patsula (1998) e Souza e Rojjanasrirat (2010). O procedimento consistiu das seguintes etapas: (a) tradução do instrumento original em inglês para o português por duas tradutoras brasileiras independentes e bilíngues, sendo uma delas juramentada, ambas familiarizadas com a cultura brasileira e americana e sem conhecimento em psicologia; (b) comparação e unificação das duas versões traduzidas pela pesquisadora, que atuou como terceira tradutora, e revisão da versão unificada; (c) retrotradução da versão unificada para o inglês por outro tradutor independente bilíngue, estadunidense, fluente em português, familiarizado com a cultura brasileira e a americana e não atuante na área de psicologia, seguida de revisão e aprovação da versão final da escala em português por Comitê de Especialistas; (d) aplicação da versão final em português em um projeto piloto. A DECA I traduzida foi aplicada e respondida por 13 avaliadores (seis mães, uma avó, um pai e cinco berçaristas de bebês). No total foram avaliados 12 bebês, sendo um deles avaliado pelo pai e pela berçarista. A DECA T foi aplicada e respondida por 13 avaliadores (seis mães, uma avó, duas assistentes de sala, duas educadoras e duas professoras de crianças). No total foram avaliadas 19 crianças, pois duas assistentes de sala avaliaram duas crianças cada, duas educadoras avaliaram, cada uma, três crianças, e duas professoras avaliaram, cada uma, três crianças. Após a aplicação do projeto piloto, a tradução para o português da DECA I/T foi considerada culturalmente adaptada e apta para futura validação
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Mell, Hugo. "Fast-slow strategies in human populations : applying insights from life history theory to explain patterns of interindividual variation". Thesis, Paris Sciences et Lettres (ComUE), 2018. http://www.theses.fr/2018PSLEE074.

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Des gradients sociaux ont été documentés pour une variété de comportements individuels. Au sein des pays occidentaux par exemple, les personnes ayant un statut socio-économique plus bas ont tendance à investir moins dans leur éducation, à fumer davantage, sont plus susceptibles de souffrir d'obésité et plus enclines à prendre des risques dans des contextes économiques. Ainsi, être exposé à des conditions de vie précaire semble engendrer une série de comportements, covariant de manière systématique. Ce syndrome comportemental a été principalement interprété comme le produit de déficits cognitifs ayant traits à la prise de décision et/ou à un manque de volonté. Dans ce manuscrit, nous explorons une approche différente, qui s'ancre dans les explications adaptationnistes des comportements humains. Au lieu d'appréhender les comportements observés chez les individus en situation de précarité comme des anomalies, ceux-ci sont perçus comme des ajustements des stratégies individuelles d'histoire de vie, adaptés à la vie dans des environnements précaires. En effet, nous approfondirons l'hypothèse selon laquelle un environnement précaire sélectionne des stratégies qui accordent davantage de poids aux bénéfices immédiats plutôt qu’aux investissements de long terme, affectant dès lors toute une gamme de comportements. Dans un premier temps, nous analyserons par le biais de modèles d'équations structurelles, différents jeux de données afin de mesurer le degré de covariation de comportements ayant trait à la reproduction, à l'investissement dans la santé et au niveau de confiance, ainsi que leur association éventuelle avec le niveau de précarité éprouvé pendant l'enfance ou à l'âge adulte. Globalement, nos résultats indiquent qu'une réduction de l’investissement dans la santé co-varie avec une stratégie de reproduction plus court-termiste, ainsi qu'un plus faible niveau de confiance. De plus, ce pattern est surreprésenté chez les personnes en situation de précarité, avec des effets persistants des conditions pendant l'enfance. En parallèle de ces travaux empiriques, nous nous sommes par ailleurs intéressés aux fondements théoriques de nos hypothèses de travail. Précisément, nous avons développé un modèle formel de stratégie d'histoire de vie prédisant les changements de préférences temporelles intra- et interindividuelles. Celui-ci nous a permis de mettre en évidence l’importance de deux facteurs distincts pour déterminer le degré optimal avec lequel des individus doivent préférer les récompenses de court-terme : 1) le niveau d'incertitude sur la probabilité de collecter une récompense délayée dans le temps, et 2) le coût d'opportunité à ne pas bénéficier de la récompense pendant la période de délai. Enfin, nous concluons ce travail en discutant des perspectives particulièrement intéressantes offertes par une intégration plus poussée de l'approche développée dans cette thèse, avec d'autres sciences sociales et sciences du comportement plus traditionnelles
Social gradients in behavior have been documented across various domains of people’s lives. In western countries, low SES individuals tend for instance to invest less in their education, to smoke more, are more subject to overweight and are more willing to take risks in financial settings. Being exposed to deprivation therefore seems to elicit a constellation of behaviors that appear to covary in a systematic fashion. This behavioral constellation of deprivation has been mostly interpreted as the product of poor decision making abilities, of a general failure of willpower. In this dissertation we explore a different interpretation that is rooted in adaptive explanations of human behavior. Instead of viewing the behaviors of low SES individuals as suboptimal deviations from a global optimum, they are seen as adjustments of people’s overall life strategies that are, from an evolutionary point of view, adaptive in the particular context of a deprived ecology. Indeed, we will explore the idea that deprived environments select for strategies that put more weight on present outcomes over uncertain future outcomes, and that this present orientation in low SES individuals propagates across a range of decision domains, giving rise to the constellation. To this aim, we first use structural equation models on observational data from a diversity of samples, to analyze the covariation between peoples’ behaviors in several relevant domains (health, reproduction, social trust) and their exposure to deprivation during childhood and/or adulthood. Overall, we find that a lower somatic effort tends to covary with a more short-term reproductive strategy, as well as lower social trust. This pattern is associated with a higher exposure to deprivation, with unique effects of early life conditions. In addition to this empirical work, we further investigate the theoretical underpinnings of our working hypotheses, from an adaptationist perspective. Specifically, we build a formal life history model to predict optimal changes in discounting within and between individuals. This allows us to highlight that the extent to which individuals prefer short-term rewards, should vary depending on two main parameters: 1) the uncertainty around their ability to actually collect delayed rewards, and 2) the opportunity costs of not having the reward during the delay. Finally, we conclude by discussing the promising perspective of further integrating the approach adopted in the present thesis, with more traditional social and behavioural sciences
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Mihajlo, Jecković. "Ultrazvučna dijagnostika upalnih oboljenja creva u komparaciji sa magnetnom rezonancom u dečjem i adolescentnom dobu". Phd thesis, Univerzitet u Novom Sadu, Medicinski fakultet u Novom Sadu, 2016. http://www.cris.uns.ac.rs/record.jsf?recordId=100637&source=NDLTD&language=en.

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UVOD: Hronične inflamatorne bolesti se ispoljavaju kao Kronova bolest i ulcerozni kolitis. Njihova značajnost ogleda se u hronicitetu kao i u stepenu u kom ograničavaju rast i razvoj dece i omladine. Brojne su posledice ovih oboljenja: dugotrajno izostajanje sa nastave, ograničavanje životnih aktivnosti i pojava komplikacija koje neretko zahvataju i druge organske sisteme. Etiologija je i dalje nerazjašnjenja navodeći kao značajan hronični inflamatorni proces u genetski uslovljenih pojedinaca a provociranih nekim infektivnim agensom. Početkom 21. veka genetska istraživanja su otkrila osnovu nasleđivanja hroničnih inflamatornih oboljenja povezanih sa NOD2 genom. Kako je u pitanju organskim sistem koji je ograničeno pristupačan kliničkom pregledu, osnovu dijagnostike čine radiološke metode. Kako je potrebno sprečiti kontinuirano izlaganje štetnom dejstvu rendgenskog zračenja istraživanja se usmeravaju ka UZ i magnetnoj rezonanca. Naše istraživanje se baziralo na mogućnostima ovih dveju metoda u svakodnevnom radu za dijagnostiku i dalje praćenje hroničnih inflamatornih bolesti creva. CILJEVI: Utvrditi senzitivnost i specifičnost ultrazvučne dijagnostike i magnetne resonance kod upalnih oboljenja creva u dečjem i adolescentnom uzrastu. Definisati i uporediti prednosti i ograničenja ultrazvučne dijagnostike sa dijagnostikom magnetne rezonace kod upalnih obolenja creva u dečjem i adolescentnom uzrastu. MATERIJAL I METODE: U istraživanje je uključeno 62. dece i adolescenata u toku prvog ataka bolesti ili ponovljenim fazama bolesti ili tokom redovnog praćenja u remisiji. Obuhvaćeni uzrast je od 4. do 18. godina. Potom su razvrstani u grupe na osnovu vrste pregleda i prisustva zadebljanja crevnog zida na A i B (pregled UZ), gde je A grupa imala zabeleženo zadebljanje crevnog zida preko 3 mm, a kod dece u grupi B debljina crevnog zida je bila između 2,5-3 mm. Sa druge strane na osnovu pregleda magnetnom rezonancom podeljeni su u A1 i B1 grupe, takođe po kriterijumu zadebljanja crevnog zida većeg od 3 mm (A1), odnosno između 2,5-3 mm (B1). Istraživanje je sprovedeno na Institutu za zdravstvenu zaštitutu dece i omladine Vojvodine i Institutu za radiologiju Kliničkog centra Vojvodine. Prvi pregled načinjen je UZ a potom je načinjen pregled magnetnom rezonanacom. Podaci su obrađivani retrospektivno i prospektivno. Kriterijumi za uključivanje u studiju pored uzrasta bili su radiološki: zadebljanje crevnog zida >3mm, postojanje narušene arhitektonike crevnog zida, zadebljanje pojedinih crevnih segmenata-dužina segmenta, znaci fibroze, odsustvo peristaltike, izražena hiperemija na kolor Doppleru, transmuralni znaci upale, uvećani mezenterijalni limfni nodusi kao i kontrolni pregledi kod dece sa ranije ustanovljenom dijagnozom. Načinjena je endoskopija sa biopsijom radi postavljanja definitivne dijagnoze, potom se pristupilo statističkoj obradi dobijenih podataka. Izračunate su prosečne i standardne devijacije i frekvencije kao i pripadajući procenti. Određivane su maksimalne i minimalne vrednosti, medijane i interkvartalni raspon. Dobijeni podaci prikazani su u grafikonima i tabelama. Za parametrijske varijable upotrebljavan je Man – Vitni U test. Za kategoričke vrednosti upotrebljeni su χ2 i Fišerov test. Nadalje su određivane senzitivnost, specifičnost kao i pozitivne i negativne prediktivne vrednosti. Veze između dva parametra uspostavljene su pomoću Pirsonove korelacione analize i linearnim regresionim modelom. Upotrebljen je program za obradu podataka SPSS 21 Statistics,a kao statistički značajne vrednosti uzete su vrednosti p<0,05. REZULTATI: Nakon statističke obrade nije zabeležena signifikantnost u pogledu zastupljenosti hroničnih inflamatornih bolesti među polovima. Statistička značajnost pronađena je u pogledu uzrasta dece u akutnoj fazi kao i remisiji bolesti. Statistička značajnost je dobijena za posmatranu debljinu crevnog zida, hiperemiju creva, prisustvo fibroze u digestivnom traktu. Primećeno je da UZ bolje razgraničava decu sa akutnim oboljenjem po pitanju zahvaćenosti segmenata. Ostala posmatrana obeležja nisu nakon statističke obrade imala statistički značaju razliku kada se procenjuju ultrazvučno ili magnetnom rezonancom. ZAKLJUČAK: Inicijalne hipoteze ovog istraživanja su nakon obrade podataka i potvrđene. Određivanjem senzitivnosti i specifičnosti UZ i MR dobijene su sledeće vrednosti: senzitivnost UZ je 88,4% naspram 92,3% koliko ima pregled magnetnom rezonancom. U pogledu specifičnosti UZ ima 88% a magnetna rezonanca 91,6%. Verifikovano je da magnetna rezonanca bolje razvrstava decu u akutnoj fazi bolesti kao i decu u remisiji. Rezultati pozitivnih i negativnih verovatnoća odnosa ne predviđaju neuspeh nijednim od ova dva pregleda.
INTRODUCTION: Chronic inflammatory diseases are manifested through two clinical entities: Crohn's disease and ulcerative colitis. Their significance lies in the chronicity and the degree to which they restrict the growth and development of children and youth. There are many consenquences that come with the very nature of the disease, in addition to long-term absence from school, limiting life activities and the occurrence of complications that often affect other organ systems. The etiology of the disease has long been in favor of the theory that a chronic inflammatory process in genetically conditioned individual is provoking an inflammation due to a certain infectious agent. However, a step closer was made regarding the etiology of the disease - when the genetic basis of inheritance studies have revealed chronic inflammatory bowel diseases were associated with NOD2 gene. It is particularly important to prevent continuous exposure to the harmful effects of X-rays. Therefore, numerous studies have been made towards the validation of complementarity, accuracy and diagnostic capabilities of ultrasound and magnetic resonance imaging as noninvasive techniques. Our research was based on the capabilities of these two methods in their daily work for diagnosis and follow-up of chronic inflammatory bowel disease. OBJECTIVES: The objectives were to determine the sensitivity and specificity of ultrasound and magnetic resonance imaging in inflammatory bowel disease in children and adolescents. Furthermore, the aim was to define and compare the advantages and limitations between ultrasound diagnosis and magnetic resonance in inflammatory bowel disease in children and adolescents. MATERIAL AND METHODS: The study included 62 children and adolescents during the first attack of disease or recurrent stages of the disease, or during regular monitoring in remission. Patients included children of both sexes, aged 4-18. Then they were sorted into groups based on the type of the examination and the presence of a thickening of the intestinal wall into groups A and B - in these groups children were examined by ultrasound, A group had observed thickening of the intestinal wall > 3 mm whereas children in group B had had thickening of the intestinal wall between 2,5-3 mm. Based on the review of MRI children were divided into groups A1 and B1, also according to the criterion of bowel wall thickening greater than 3mm (A1) and between 2,5-3mm (B1). The research was conducted at the Institute for Health Protection of Children and Youth and the Institute of Radiology, Clinical Center of Vojvodina. The first review was made by ultrasound, followed by the review of magnetic resonance. Data were analyzed retrospectively and prospectively. Criteria for inclusion in the study were: thickening of the intestinal wall greater than 3 mm, the existence of disturbed intestinal wall architectural structure, no clear distinction of layers, abnormal thickening of certain intestinal segments, signs of fibrosis, the absence of peristalsis, expressed hyperemia on color Doppler, transmural inflammation, increased mesenterial lymph nodes as well as check-ups for children with previously established diagnosis. Endosccopy with biopsy has made for the definitive diagnosis and then we approached statistical analysis of the data obtained. The data are presented in graphs and tables. For parametric variables we used Man - Whitney U test. For categorical values χ2 and Fisher's test were used. Further the sensitivity, specificity and positive and negative predictive values were determined. Relationship between these two parameters were established using Pearson correlation analysis and linear regression model. For data processing we used the program SPSS Statistics 21, statistically significant values were taken p values <0.05. RESULTS: After statistical analysis there was no for the number of chronic inflammatory diseases between the sexes. Statistical significance was found in terms of age of the children during the acute phase as well as remission. Statistical significance was obtained for the observed thickness of the intestinal wall, intestinal hyperemia, the presence of fibrosis in the digestive tract. It was noted that US better demarcates children with acute disease in terms of involvement of segments. Other features are not observed as significant after the statistical analysis. CONCLUSION: The initial hypothesis of this study, after data processing were confirmed. By determining the sensitivity and specificity of ultrasound MRI results we came to the following results: sensitivity of ultrasound was 88,4% versus 92,3%, for magnetic resonance. In terms of specifics UZ has a 88% and 91,6% of magnetic resonance imaging. The classification of children in the acute phase of the disease as well as children in remission was better when MRI was used. The results of positive and negative predictions do not predict the probability of failure in neither of these methods.
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Milliet, De Faverges Marie. "Développement et implémentation de modèles apprenants pour l’exploitation des grandes gares". Electronic Thesis or Diss., Paris, CNAM, 2020. http://www.theses.fr/2020CNAM1283.

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Cette thèse traite de l’incertitude et de la robustesse dans les problèmes de d´décision, avec le cas d’application des affectations de quais en gare en cas de retards. Une m´méthodologie en deux parties est proposée pour aborder ce problème. Dans un premier temps, les archives de données de retards sont utilisées pour construire des modèles de prédiction de distribution de probabilités conditionnellement aux valeurs d’un ensemble de variables explicatives. Une m´méthodologie de validation et d’évaluation de ces prédictions est mise en place afin d’assurer leur fiabilité pour de la prise de d´décision. Le problème d’affectations de quais pouvant être vu comme une recherche de clique de taille maximum, ces distributions prédites sont utilisées dans une seconde partie pour ajouter des pondérations pénalisant les risques de rupture des arêtes en cas de retard. Des algorithmes de recherche locale ont ´été utilisés et les expériences ont montré une importante baisse de conflits
This thesis deals with uncertainty and robustness in decision problems, with the case of the train platforming problem subject to delays. A two-part methodology is proposed to address this problem. First, delay records are used to build models predicting probability distributions conditionnaly to a set of explanatory variables. A methodology to validate and evaluate these predictions is proposed to ensure their reliability for decision-making. As the train platforming problem can be seen as a weighted clique problem, these predicted distributions are used in a second part to add weights on edges to penalize risk of conflict. Local search algorithms are used and experiments show a significant decrease in conflicts
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Grasreiner, Sebastian. "Combustion modeling for virtual SI engine calibration with the help of 0D/3D methods". Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2012. http://nbn-resolving.de/urn:nbn:de:bsz:105-qucosa-90518.

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Spark ignited engines are still important for conventional as well as for hybrid power trains and are thus objective to optimization. Today a lot of functionalities arise from software solutions, which have to be calibrated. Modern engine technologies provide an extensive variability considering their valve train, fuel injection and load control. Thus, calibration efforts are really high and shall be reduced by introduction of virtual methods. In this work a physical 0D combustion model is set up, which can cope with a new generation of spark ignition engines. Therefore, at first cylinder thermodynamics are modeled and validated in the whole engine map with the help of a real-time capable approach. Afterwards an up to date turbulence model is introduced, which is based on a quasi-dimensional k-epsilon-approach and can cope with turbulence production from large scale shearing. A simplified model for ignition delay is implemented which emphasizes the transfer from laminar to turbulent flame propagation after ignition. The modeling is completed with the calculation of overall heat release rates in a 0D entrainment approach with the help of turbulent flame velocities. After validation of all sub-models, the 0D combustion prediction is used in combination with a 1D gas exchange analysis to virtually calibrate the modern engine torque structure and the ECU function for exhaust gas temperature with extensive simulations
Moderne Ottomotoren spielen heute sowohl in konventionellen als auch hybriden Fahrzeugantrieben eine große Rolle. Aktuelle Konzepte sind hochvariabel bezüglich Ventilsteuerung, Kraftstoffeinspritzung und Laststeuerung und ihre Optimierungspotentiale erwachsen zumeist aus neuen Softwarefunktionen. Deren Applikation ist zeit- und kostenintensiv und soll durch virtuelle Methoden unterstützt werden. In der vorliegenden Arbeit wird ein physikalisches 0D Verbrennungsmodell für Ottomotoren aufgebaut und bis zur praktischen Anwendung geführt. Dafür wurde zuerst die Thermodynamik echtzeitfähig modelliert und im gesamten Motorenkennfeld abgeglichen. Der Aufbau eines neuen Turbulenzmodells auf Basis der quasidimensionalen k-epsilon-Gleichung ermöglicht anschließend, die veränderlichen Einflüsse globaler Ladungsbewegung auf die Turbulenz abzubilden. Für den Brennverzug wurde ein vereinfachtes Modell abgeleitet, welches den Übergang von laminarer zu turbulenter Flammenausbreitung nach der Zündung in den Vordergrund stellt. Der restliche Brennverlauf wird durch die physikalische Ermittlung der turbulenten Brenngeschwindigkeit in einem 0D Entrainment-Ansatz dargestellt. Nach Validierung aller Teilmodelle erfolgt die virtuelle Bedatung der Momentenstruktur und der Abgastemperaturfunktion für das Motorsteuergerät
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Lin, Tzu-Ya, e 林姿雅. "Development of Delay-Based Base Train Equivalents for Multiple-Type Train Operations". Thesis, 2012. http://ndltd.ncl.edu.tw/handle/72685302729051998977.

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碩士
國立臺灣大學
土木工程學研究所
100
A conventional railway system usually has multiple types of trains with various service patterns operating on the same line. This difference in train characteristics lead to different capacity impacts on the system. Recently a new concept was proposed to use Base train equivalent (BTE) standardize different train type into base train; this concept is similar to Passenger car equivalent (PCE) on highway. By convert these non-base trains to a standardized unit we call the convert volume as base train units (BTU). However, previous study focuses on the development of BTE with analytical capacity models as opposed to delay-based capacity models, such as parametric or simulation models. Consequently, this research develops delay-based BTE models for delay-based capacity models. Since BTE is developed based capacity models its value also varies with key capacity factors, such as traffic, operating and route characteristics. However, in terms of a particular route, BTE would only vary with traffic volume and heterogeneity since most of the other factors will be fixed. Therefore, this study first develops dynamic BTE models with consideration of volume and heterogeneity. Besides that, this study also develops fixed BTE model with consideration of heterogeneity since its impact is far more significant than traffic volume. Another variation in the development is the number of train types. For only two-type train operations, BTE can be directly computed based on the developed BTE models. However, the same model cannot be directly applied to multiple-type train operations (three or more types) due to due to limited output of variables from the capacity models. This study adopts the concept of vector projection to identify single value for each BTE in this case. With the proposed models, the unit of delay-based rail capacity can be converted into a standard unit. The impact of an additional train can be easily assessed, and capacity measurements from different lines or systems can be compared and evaluated.
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"Establishing a Biomarker of Cellular Aging for Mesenchymal Stem Cells and Investigating Their Regenerative Potential". Tulane University, 2019.

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Hsin-IChen e 陳心一. "Long Distance Train Delay Prediction: Evidence from Taiwan Railway System". Thesis, 2010. http://ndltd.ncl.edu.tw/handle/62617643261656329122.

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碩士
國立成功大學
交通管理學系碩博士班
98
Delay of railway trains is highly affecting reliability of the system, and has significant negative impact on customers' satisfaction. Simulation models often used in previous research and in practice to predict the train delay; due to the growth of the scale of system, it turned to be too costly to develop on such problem. This research suggesting an approach on predicts train delay in the short term by linear model and neural network. With the train operation data of Taiwan Railway Administration for three month, we build several models on predicting weather the train will be delayed on the terminal station, the number of delay incidents on the train's journey and the length ratio of delay time, based on the predictive factors of train, route and environment. We'd found that delay occurs much often on weekends and holidays; the congestion delay is not obvious in the research area; specific class of train had seriously high delay rates; delay increase from the morning to the evening in every single day; Tze-Chiang express have different delay condition on each directions of research section. This research suggests that the system operator should build a special holiday timetable, according to the different passenger characteristic and destination between working days and non-working days, also we should increase the headway progressively to avoid the delay accumulate on the time period in a day.
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Lin, Yu-Min, e 林育民. "Exploring the Reasons of Train Delay: A Case Study of Tilting Train of Taiwan Railways Administration". Thesis, 2016. http://ndltd.ncl.edu.tw/handle/4wneqn.

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碩士
國立宜蘭大學
應用經濟與管理學系經營管理碩士班
104
Railway transport require precise calculation and careful planning. Therefore system reliability is an important performance criteria. Railway system is a close system, thus if delay occur, other trains might also be affected, a form of “chain effect”. Taiwan Railways Administration (TRA) tilting train delay data were collected and analyzed in this study. Train delay can divided into: station delay, train delay, route operation delay and other delay. After discovered main issue of train delay occurrence, this study provide suggestions for train delay prevention and improvement.
20

Huang, Pei-Tzu, e 黃佩慈. "Reliability Evaluation of a Multistate Railway Transportation Network with Train Delay". Thesis, 2019. http://ndltd.ncl.edu.tw/handle/h73c9x.

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Abstract (sommario):
碩士
國立臺灣科技大學
工業管理系
107
In order to relieve working pressure and daily hustle, tourism plays an indispensable role in people’s lives. For most travelers, railway transportation is the primary conveyance because of its convenience and cost-effective. Accordingly, it’s difficult to provide lots of travelers with train service, especially on holidays and special festivals. Significantly, to measure whether the railway transportation system can meet travelers’ requirements, this thesis focuses on investigating the network reliability of a railway transportation system from a travel agency perspective. In which, such network reliability can be treated as a carrying performance indicator. A railway transportation system can be modeled as a multistate railway transportation network (MRTN), in which each node represents a transfer station and each arc denotes a train carrying passengers between a pair of stations. This dissertation first considers a MRTN meeting single railway travel demand while trains are on schedule. Therefore, the network reliability of the MRTN is defined as the probability that a requested number of train carriages can be carried successfully from an origin to a final destination station. Moreover, a MRTN is further extended to each train may have delay conditions in the busy congested rail system. Under train delay consideration, a minimal train-path (MP) has a working probability that the connection still keeps. Regarding two models this study, the algorithms are proposed in terms of minimal paths to evaluate the network reliability. Additionally, the working probability of a MP is added to the reliability calculation in the extended model. Finally, a case study of the Taiwanese railway transportation system is utilized to demonstrate how to implement the proposed algorithms, and then discuss the managerial implications of the reliability to travel agency in their decision-making.
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CHANG, YU-WEI, e 張祐瑋. "The impact of personal traits, age and domain knowledge on Decoy effect". Thesis, 2016. http://ndltd.ncl.edu.tw/handle/70667524541503594317.

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Abstract (sommario):
碩士
國立臺北大學
國際企業研究所
104
The needs of people are various and unique, in order to meet the needs, researchers believe that the various sorts and varieties of selection can satisfies more widely of needs. However, Decoy Effect (a phenomenon that an option added increases the favorable perceptions of similar, but superior, items in the choice set) indicate that the preference of people can be changed by adding a decoy option. Everyone has different thoughts even they get the same message, the aims of the thesis are to know how consumers react to decoy effect; we want to know the impact of these factors on decoy effects, and the intensity of effects. 1. To verify how personal traits (self-confidence, need of cognition) affect decoy effect. 2. To verify the relationship between age and decoy effect. 3. To verify the relationship between domain knowledge and decoy effect. 4. To provide the reasoning relationship between different theories. The results of this study show that Domain Knowledge and Self-Confidence significantly attenuates the intensity of decoy effect. We inference that experts don’t need to reference the information provided by choice set; and high Self-Confidence people more likely to trust their own experience.
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Wu, Nan-Lin, e 吳南霖. "Roles of TRAIL and decoy receptor 3 in epidermal keratinocyte terminal differentiation and inflammatory skin diseases". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/26652209456456108051.

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Abstract (sommario):
博士
國立臺灣大學
藥理學研究所
101
Skin provides the primary barrier to prevent excessive water loss and protect against the external insults and invasion of pathogens. The homeostasis of normal skin is maintained by the balance between continuous replenishment of proliferating keratinocytes and well-controlled cell death. Cornification, the process of terminal differentiation of epidermal keratinocytes, is a special form of programmed cell death in skin and distinct from apoptotic cell death. These terminally differentiated, dead keratinocytes construct the outermost cornified layer, which is the principal barrier of skin. Skin homeostasis is also controlled by coordination between different cellular effectors in skin including epidermal keratinocytes, dermal fibroblasts and various immunocytes. Disturbance of skin homeostasis can lead to diverse disorders characterized by aberrant growth, cell death, differentiation or severe inflammation. Like immunocytes, epidermal keratinocytes also can express many members of tumor necrosis factor (TNF) and tumor necrosis factor receptor (TNFR) superfamily. Although many functions of TNF and TNFR superfamily in immune cells have been revealed, the known biological roles in skin still remain limited. In our studies, we first tried to evaluate the effect of tumor necrosis factor related apoptosis-inducing ligand (TRAIL), which is a well-known apoptosis inducer in transformed cells, on primary human epidermal keratinocytes, focusing on keratinocyte differentiation and the underlying molecular mechanisms. Secondly, we investigated the expression of decoy receptor 3 (DcR3) in psoriasis, which is characterized by aberrant keratinocyte proliferation and differentiation, inflammation, and angiogenesis. DcR3 is a soluble receptor of Fas ligand (FasL), LIGHT (TNFSF14) and TNF-like molecule 1A (TL1A), and plays pleiotropic roles in many inflammatory and autoimmune disorders and malignant diseases. In cutaneous biology, DcR3 is expressed in primary human epidermal keratinocytes and is up-regulated in skin lesions of psoriasis. However, the regulatory mechanisms of DcR3 over-expression in skin lesions of psoriasis are unknown. For the part I, we found TRAIL could induce the expression of keratinocyte differentiation markers involucrin and type 1 transglutaminase in normal human epidermal keratinocytes. The induction of differentiation occurred mainly under the activation of caspases 3 and 8, and apoptosis could also be triggered. Inhibition of these apoptotic caspases attenuated both of the apoptosis and differentiation of keratinocytes caused by TRAIL, but barely affected the induction of differentiation caused by calcium and phorbol 12-myristate 13-acetate. The differential regulation of ERK and p38 activation by TRAIL was also observed. Moreover, the degradation of p63 was induced by TRAIL-elicited caspase activation. However, the existence of p63 is essential for the initiation of keratinocyte differentiation caused by TRAIL because knockdown of ΔNp63 decreased the TRAIL-induced differentiation. Taken together, our results suggest that TRAIL can be an inducer of both differentiation and apoptosis in human keratinocytes, and that caspases critically mediate these processes. This study identifies a new role of apoptotic caspases for terminal differentiation of keratinocytes and further elucidates the molecular pathways involved in this unique model of cell death. For part II, we demonstrate that DcR3 can be detected in both dermal blood vessels and epidermal layers of psoriatic skin lesions. Analysis of serum samples showed that DcR3 was elevated, but FasL was downregulated in psoriatic patients compared with normal individuals. Additional studies revealed a central role of epidermal growth factor receptor (EGFR) in controlling the basal expression of DcR3 in keratinocytes. Activation of EGFR by epidermal growth factor (EGF) or transforming growth factor (TGF)-alpha strikingly upregulated DcR3 production. TNF-alpha enhanced DcR3 expression in both keratinocytes and endothelial cells compared with various inflammatory cytokines involved in psoriasis. Additionally, TNF-alpha-enhanced DcR3 expression in keratinocytes was inhibited when EGFR was knocked down or EGFR inhibitor was used. The NF-kappa B pathway was critically involved in the molecular mechanisms underlying the action of EGFR and TNF-alpha. Collectively, the novel regulatory mechanisms of DcR3 expression in keratinocytes and endothelial cells provide new insights into the pathogenesis of psoriasis.
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Huan-Kuang, Chang, e 張煥光. "Analytic Time Delay Study of Train Failure Treatment Mode for MRT System - A Case Study of Metro Taipei". Thesis, 2003. http://ndltd.ncl.edu.tw/handle/93694150793715546417.

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Abstract (sommario):
碩士
國立臺灣科技大學
管理研究所
91
The major purpose of this dissertation is to clarify the train failure treatment procedure and delay time. Based on the system concept, FMEA method, and comprehensive MRT system we induced 8 modes of train failure treatment. Based on the work and time study we developed the optimistic, average, pessimism time standards for train subsystems. Through the case study of Metro Taipei and SPSS statistic analysis we summarized finding and suggestions of the correlated factors as environment, aging, human error, equipment, time value, operation for continuous improvement (CI). We also summarized our results and make some comments about future research.
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Manitz, Juliane. "Statistical Inference for Propagation Processes on Complex Networks". Doctoral thesis, 2014. http://hdl.handle.net/11858/00-1735-0000-0022-5F38-B.

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Abstract (sommario):
Die Methoden der Netzwerktheorie erfreuen sich wachsender Beliebtheit, da sie die Darstellung von komplexen Systemen durch Netzwerke erlauben. Diese werden nur mit einer Menge von Knoten erfasst, die durch Kanten verbunden werden. Derzeit verfügbare Methoden beschränken sich hauptsächlich auf die deskriptive Analyse der Netzwerkstruktur. In der hier vorliegenden Arbeit werden verschiedene Ansätze für die Inferenz über Prozessen in komplexen Netzwerken vorgestellt. Diese Prozesse beeinflussen messbare Größen in Netzwerkknoten und werden durch eine Menge von Zufallszahlen beschrieben. Alle vorgestellten Methoden sind durch praktische Anwendungen motiviert, wie die Übertragung von Lebensmittelinfektionen, die Verbreitung von Zugverspätungen, oder auch die Regulierung von genetischen Effekten. Zunächst wird ein allgemeines dynamisches Metapopulationsmodell für die Verbreitung von Lebensmittelinfektionen vorgestellt, welches die lokalen Infektionsdynamiken mit den netzwerkbasierten Transportwegen von kontaminierten Lebensmitteln zusammenführt. Dieses Modell ermöglicht die effiziente Simulationen verschiedener realistischer Lebensmittelinfektionsepidemien. Zweitens wird ein explorativer Ansatz zur Ursprungsbestimmung von Verbreitungsprozessen entwickelt. Auf Grundlage einer netzwerkbasierten Redefinition der geodätischen Distanz können komplexe Verbreitungsmuster in ein systematisches, kreisrundes Ausbreitungsschema projiziert werden. Dies gilt genau dann, wenn der Ursprungsnetzwerkknoten als Bezugspunkt gewählt wird. Die Methode wird erfolgreich auf den EHEC/HUS Epidemie 2011 in Deutschland angewandt. Die Ergebnisse legen nahe, dass die Methode die aufwändigen Standarduntersuchungen bei Lebensmittelinfektionsepidemien sinnvoll ergänzen kann. Zudem kann dieser explorative Ansatz zur Identifikation von Ursprungsverspätungen in Transportnetzwerken angewandt werden. Die Ergebnisse von umfangreichen Simulationsstudien mit verschiedenstensten Übertragungsmechanismen lassen auf eine allgemeine Anwendbarkeit des Ansatzes bei der Ursprungsbestimmung von Verbreitungsprozessen in vielfältigen Bereichen hoffen. Schließlich wird gezeigt, dass kernelbasierte Methoden eine Alternative für die statistische Analyse von Prozessen in Netzwerken darstellen können. Es wurde ein netzwerkbasierter Kern für den logistischen Kernel Machine Test entwickelt, welcher die nahtlose Integration von biologischem Wissen in die Analyse von Daten aus genomweiten Assoziationsstudien erlaubt. Die Methode wird erfolgreich bei der Analyse genetischer Ursachen für rheumatische Arthritis und Lungenkrebs getestet. Zusammenfassend machen die Ergebnisse der vorgestellten Methoden deutlich, dass die Netzwerk-theoretische Analyse von Verbreitungsprozessen einen wesentlichen Beitrag zur Beantwortung verschiedenster Fragestellungen in unterschiedlichen Anwendungen liefern kann.
25

Conte, Carla. "Identifying dependencies among delays". Doctoral thesis, 2008. http://hdl.handle.net/11858/00-1735-0000-000D-F124-2.

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