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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.
761

Étude de l’influence de différentes méthodes de fabrication sur l’architecture et les propriétés physico-chimiques des nanoparticules à base de PEG-b-PLA

Rode García, Teresita 08 1900 (has links)
No description available.
762

Le log complet de la stratigrahie de la zone rhénane ainsi que les modilités stratigraphiques, sédimentaires et structurales de la transition socle-couverture : application à la géothermie profonde / The complete log of the stratigraphy of the Upper Rhine Graben as well as the stratigraphie, sedimentary and structural modalities of the "cover-basement" transition : application to deep geothermal energy

Aichholzer, Coralie 10 October 2019 (has links)
Depuis la mise en place en 2010, d’une nouvelle tarification française sur le tarif de l’énergie géothermique, l’Alsace est la région de France la plus dynamique quant à la réalisation de forages géothermiques profonds à haute température (>150°C). Ainsi, l’approche géologique, qui a été primordiale pour les forages de Rittershoffen, le sera encore davantage pour les projets à venir compte tenu de la méconnaissance géologique de certaines zones profondes du bassin rhénan. Cette étude propose d’appréhender la compréhension de l’architecture stratigraphique et séquentielle des formations de la couverture sédimentaire rhénane. 15 puits profonds ont été réinterprétés et corrélés à travers l’ensemble du bassin, permettant l’élaboration d’une colonne stratigraphique complète incluant le sommet et la base de chaque formation. Ces réinterprétations ont également mis en lumière le signal caractéristique de la diagraphie gamma-ray (GR) de chacune des formations de la colonne stratigraphique rhénane. De plus, la caractérisation lithostratigraphique du passage entre le socle et la couverture sédimentaire a fait l’objet d’un axe important de recherche. / Since the introduction of a new French pricing system for geothermal energy in 2010, Alsace has been the most dynamic region in France for deep geothermal drilling at high temperatures (>150°C). Thus, the geological approach, which has been essential for the Rittershoffen boreholes, will be even more for future projects given the lack of geological knowledge of some deep parts of the URG. This study aims at understanding the stratigraphic and sequential architecture of the formations of the URG sedimentary cover. 15 deep wells were reinterpreted and correlated throughout the basin, allowing the development of a complete stratigraphic column including the top and base of each formation. These reinterpretations also highlighted the characteristic gamma-ray signal (GR) of each of the formations in the URG stratigraphic column. In addition, the lithostratigraphic characterization of the transition between the basement and the sedimentary cover was the subject of an important research focus.
763

Traffic Safety Assessment of Different Toll Collection Systems on Expressways Using Multiple Analytical Techniques

Abuzwidah, Muamer 01 January 2014 (has links)
Traffic safety has been considered one of the most important issues in the transportation field. Crashes have caused extensive human and economic losses. With the objective of reducing crash occurrence and alleviating crash injury severity, major efforts have been dedicated to reveal the hazardous factors that affect crash occurrence. With these consistent efforts, both fatalities and fatality rates from road traffic crashes in many countries have been steadily declining over the last ten years. Nevertheless, according to the World Health Organization, the world still lost 1.24 million lives from road traffic crashes in the year of 2013. And without action, traffic crashes on the roads network are predicted to result in deaths of around 1.9 million people, and up to 50 million more people suffer non-fatal injuries annually, with many incurring a disability as a result of their injury by the year 2020. To meet the transportation needs, the use of expressways (toll roads) has risen dramatically in many countries in the past decade. In fact, freeways and expressways are considered an important part of any successful transportation system. These facilities carry the majority of daily trips on the transportation network. Although expressways offer high level of service, and are considered the safest among other types of roads, traditional toll collection systems may have both safety and operational challenges. The traditional toll plazas still experience many crashes, many of which are severe. Therefore, it becomes more important to evaluate the traffic safety impacts of using different tolling systems. The main focus of the research in this dissertation is to provide an up-to-date safety impact of using different toll collection systems, as well as providing safety guidelines for these facilities to promote safety and enhance mobility on expressways. In this study, an extensive data collection was conducted that included one hundred mainline toll plazas located on approximately 750 miles of expressways in Florida. Multiple sources of data available online maintained by Florida Department of Transportation were utilized to identify traffic, geometric and geographic characteristics of the locations as well as investigating and determination of the most complete and accurate data. Different methods of observational before-after and Cross-Sectional techniques were used to evaluate the safety effectiveness of applying different treatments on expressways. The Before-After method includes Naive Before-After, Before-After with Comparison Group, and Before-After with Empirical Bayesian. A set of Safety Performance Functions (SPFs) which predict crash frequency as a function of explanatory variables were developed at the aggregate level using crash data and the corresponding exposure and risk factors. Results of the aggregate traffic safety analysis can be used to identify the hazardous locations (hot spots) such as traditional toll plazas, and also to predict crash frequency for untreated sites in the after period in the Before-After with EB method or derive Crash Modification Factors (CMF) for the treatment using the Cross-Sectional method. This type of analysis is usually used to improve geometric characteristics and mainly focus on discovering the risk factors that are related to the total crash frequency, specific crash type, and/or different crash severity levels. Both simple SPFs (with traffic volume only as an explanatory variable) and full SPFs (with traffic volume and additional explanatory variable(s)) were used to estimate the CMFs and only CMFs with lower standard error were recommended. The results of this study proved that safety effectiveness was significantly improved across all locations that were upgraded from Traditional Mainline Toll Plazas (TMTP) to the Hybrid Mainline Toll Plazas (HMTP) system. This treatment significantly reduced total, Fatal-and-Injury (F+I), and Rear-End crashes by 47, 46 and 65 percent, respectively. Moreover, this study examined the traffic safety impact of using different designs, and diverge-and-merge areas of the HMTP. This design combines either express Open Road Tolling (ORT) lanes on the mainline and separate traditional toll collection to the side (design-1), or traditional toll collection on the mainline and separate ORT lanes to the side (design-2). It was also proven that there is a significant difference between these designs, and there is an indication that design-1 is safer and the majority of crashes occurred at diverge-and-merge areas before and after these facilities. However, design-2 could be a good temporary design at locations that have low prepaid transponder (Electronic Toll Collection (ETC)) users. In other words, it is dependent upon the percentage of the ETC users. As this percentage increases, more traffic will need to diverge and merge; thus, this design becomes riskier. In addition, the results indicated significant relationships between the crash frequency and toll plaza types, annual average daily traffic, and drivers* age. The analysis showed that the conversion from TMTP to the All-Electronic Toll Collection (AETC) system resulted in an average reduction of 77, 76, and 67 percent for total, F+I, and Property Damage Only (PDO) crashes, respectively; for rear end and Lane Change Related (LCR) crashes the average reductions were 81 and 75 percent, respectively. The conversion from HMTP to AETC system enhanced traffic safety by reducing crashes by an average of 23, 29 and 19 percent for total, F+I, and PDO crashes; also, for rear end and LCR crashes, the average reductions were 15 and 21 percent, respectively. Based on these results, the use of AETC system changed toll plazas from the highest risk sections on Expressways to be similar to regular segments. Therefore, it can be concluded that the use of AETC system was proven to be an excellent solution to several traffic operations as well as environmental and economic problems. For those agencies that cannot adopt the HMTP and the AETC systems, improving traffic safety at traditional toll plazas should take a priority. This study also evaluates the safety effectiveness of the implementation of High-Occupancy Toll lanes (HOT Lanes) as well as adding roadway lighting to expressways. The results showed that there were no significant impact of the implementation of HOT lanes on the roadway segment as a whole (HOT and Regular Lanes combined). But there was a significant difference between the regular lanes and the HOT lanes at the same roadway segment; the crash count increased at the regular lanes and decreased at the HOT lanes. It was found that the total and F+I crashes were reduced at the HOT lanes by an average of 25 and 45 percent, respectively. This may be attributable to the fact that the HOT lanes became a highway within a highway. Moreover adding roadway lighting has significantly improved traffic safety on the expressways by reducing the night crashes by approximately 35 percent. Overall, the proposed analyses of the safety effectiveness of using different toll collection systems are useful in providing expressway authorities with detailed information on where countermeasures must be implemented. This study provided for the first time an up-to-date safety impact of using different toll collection systems, also developed safety guidelines for these systems which would be useful for practitioners and roadway users.
764

Same-Sex Sexual Assault in the Military

Croft, Lauren 01 May 2015 (has links)
Sexual assault in the military is a large concern for the Department of Defense. They recognize it as an important and complex problem that needs to be addressed. In recent years, efforts have been initiated in order to improve the handling of sexual assault cases and data retention. An entirely new program has been created in order to address these cases. Focusing on the occurrence of same-sex assaults heightens the sensitivity of matters. This is due to the precarious and only very recent acceptance of homosexuals in the military. In the past, service members, homosexual or otherwise, may have been concerned with having any connection to homosexual acts. This is because such acts could result in removal from the military. However, in 2011 the “Don’t Ask, Don’t Tell” Repeal Act went into effect. This act allowed for the open service of homosexuals in the military. Around this same time period, reports from the Department of Defense indicated a rise in the number of sexual assault reports. This thesis analyzes the affect that policies from the Department of Defense and legislation such as the “Don’t Ask, Don’t Tell” Repeal Act have on reports of same-sex sexual assault in the military. Through research, this thesis finds that the enactments of various policies have had a measurable impact on treatment of same-sex sexual assault reports in the military, though not necessarily in the way certain media reports might suggest. This thesis also examines the history concerning homosexual service in the military, in order to provide a picture of the national attitudes towards homosexual service in the military, and why certain groups may blame the Lesbian, Gay, Bisexual, and Transgender for this rise in reports.
765

Financing Ohio’s Public Schools through the Ohio Lottery: Quantitative and Qualitative Dimensions of the Lottery’s Tax Incidence

Daberkow, Kevin S. 25 July 2012 (has links)
No description available.
766

Nio trähus ifrån 1200-talet - Hur har de kunnat bevaras?

Johansson, Henrik January 2022 (has links)
The oldest profane log timber houses in Sweden dates back to the 13th century. This study investigates 9 of them. All of the houses are built with interlocking joints and the chosen timber are pine or fir. They are rather modest in size. Two are storage houses on church grounds, the others have had different functions on rural farms. Several of them are still in use as none heated storage space. Originally, they often had the important function of storing the next year’s seed. They were well built with great craftmanship and was meant to be used over several generations. Additional features on the houses that have been beneficial for their longevity are their detachability. They can be moved to find new use, and also being sold away to new owners. Furthermore, they were one of the first generations of houses with a stone foundation. A local adaption in the Middle Sweden were foundation on stilts, another way to avoid contact with the humidity of the soil. Six of the houses are situated in the County of Dalarna and are an important part of the County heritage. With help of the archaeological record, it is possible to follow the development of the house building technology from the traditional Viking age long houses, to the emergence of the first surviving timber houses. This study investigates nine of the houses with the different factors that have contributed to their longevity. Important features have been the solid log timber construction with interlocking joints, together with the foundations which protected the timber from the humidity of the soil. The outer roof lining has been wood shavings or a layer of birch bark together with timber. These building components had developed to maturity in the early 13th century and combined they formed a sustainable house format. The houses have been useful for their owners over the centuries, hence been well maintained. The study also discusses the authenticity of the houses. / De äldsta bevarade profana trähusen i Sverige härrör ifrån 1200-talet och de är samtliga förhållandevis små förrådsbodar eller hus. Studien undersöker nio av dem. Åtta av dem finns i de tre mellansvenska landskapen; Dalarna, Hälsingland och Jämtland. Där kallas de ofta för härbren. En kyrkbod finns i Småland. De är alla knuttimrade hus byggda av virke ifrån furu eller gran. Fem står på en hel stengrund, medan tre står på stolpunderreden, som är en mellansvensk variant av husunderrede för bodar. Ytterligare ett står på stenplintar. Alla dessa typer av grunder har skyddat husen ifrån markfukt. Två är kyrkbodar och har inledningsvis fungerat som så kallade tiondebodar, de andra har haft olika uppgifter på allmogens gårdar som ouppvärmda förrådshus. En viktig uppgift var ofta att lagra nästa års utsäde. De är byggda med stor hantverksskicklighet och omsorg, då de var menade att stå i flera släktled. Som knuttimrade hus har de kunnat monteras ned för underhåll, eller flytt till en annan plats där de behövts bättre. De har också kunnat säljas. I Mellansverige ses de många medeltida bodarna som en viktig del av landskapens kulturarv. Den småländska kyrkboden i Ingatorp anses vara speciellt väl bevarad ifrån medeltiden och har nyligen genomgått en varsam restaurering. Dessa trähus ifrån 1200-talet lyfter frågan om hur husbyggnadstraditionen utvecklades ifrån de tidigare långhusen, som inte blivit bevarade, fram till dessa våra äldsta bevarade trähus. Man kan följa utvecklingen i det arkeologiska fyndmaterialet. Uppsatsen undersöker husen med frågeställningen om vad som bidragit till husens långa levnadstid, samt hur deras autenticitet påverkats genom åren. Bland flera närvarande förhållanden finns den stabila takbärande konstruktionen med knuttimrade timmerväggar, samt att husen har varit skyddade emot markfukt genom de isolerande grunder som valts. De två typerna av takytterskikt som använts är träspån samt näver/takved. Dessa byggnadskomponenter för väggar, grund och tak var vid tiden förhållandevis nya. I början av 1200-talet hade de på var sitt håll mognat teknisk. När de kombinerades bildade de ett hållbart husformat. Vidare har husen fyllt en funktion för ägarna genom århundradena och därför fått underhåll. Studien har gjorts genom litteratur- och fältstudier samt personlig kommunikation.
767

CURE RATE AND DESTRUCTIVE CURE RATE MODELS UNDER PROPORTIONAL ODDS LIFETIME DISTRIBUTIONS

FENG, TIAN January 2019 (has links)
Cure rate models, introduced by Boag (1949), are very commonly used while modelling lifetime data involving long time survivors. Applications of cure rate models can be seen in biomedical science, industrial reliability, finance, manufacturing, demography and criminology. In this thesis, cure rate models are discussed under a competing cause scenario, with the assumption of proportional odds (PO) lifetime distributions for the susceptibles, and statistical inferential methods are then developed based on right-censored data. In Chapter 2, a flexible cure rate model is discussed by assuming the number of competing causes for the event of interest following the Conway-Maxwell (COM) Poisson distribution, and their corresponding lifetimes of non-cured or susceptible individuals can be described by PO model. This provides a natural extension of the work of Gu et al. (2011) who had considered a geometric number of competing causes. Under right censoring, maximum likelihood estimators (MLEs) are obtained by the use of expectation-maximization (EM) algorithm. An extensive Monte Carlo simulation study is carried out for various scenarios, and model discrimination between some well-known cure models like geometric, Poisson and Bernoulli is also examined. The goodness-of-fit and model diagnostics of the model are also discussed. A cutaneous melanoma dataset example is used to illustrate the models as well as the inferential methods. Next, in Chapter 3, the destructive cure rate models, introduced by Rodrigues et al. (2011), are discussed under the PO assumption. Here, the initial number of competing causes is modelled by a weighted Poisson distribution with special focus on exponentially weighted Poisson, length-biased Poisson and negative binomial distributions. Then, a damage distribution is introduced for the number of initial causes which do not get destroyed. An EM-type algorithm for computing the MLEs is developed. An extensive simulation study is carried out for various scenarios, and model discrimination between the three weighted Poisson distributions is also examined. All the models and methods of estimation are evaluated through a simulation study. A cutaneous melanoma dataset example is used to illustrate the models as well as the inferential methods. In Chapter 4, frailty cure rate models are discussed under a gamma frailty wherein the initial number of competing causes is described by a Conway-Maxwell (COM) Poisson distribution in which the lifetimes of non-cured individuals can be described by PO model. The detailed steps of the EM algorithm are then developed for this model and an extensive simulation study is carried out to evaluate the performance of the proposed model and the estimation method. A cutaneous melanoma dataset as well as a simulated data are used for illustrative purposes. Finally, Chapter 5 outlines the work carried out in the thesis and also suggests some problems of further research interest. / Thesis / Doctor of Philosophy (PhD)
768

Att säkerställa ett begränsat material för mindre aktörer : En fallstudie på KG List / To secure limited material for smaller enterprises : A case study on KG List

Olsen, Oskar, Strandberg, Axel January 2024 (has links)
Course: Degree project in Supply Chain Management, Master of science within business and economics, 30 credits Title: To secure limited material for smaller enterprises - A case study on KG ListAuthors: Oskar Olsen & Axel StrandbergSupervisor: Åsa GustavssonExaminator: Peter Berling Background: In an increasingly competitive business market, the sourcing process needs to be optimized to gain advantages over competitors. Companies using limited resources suffer from not being able to secure material in different ways. Being a small enterprise also gives additional negative consequential effects. To be able to decrease the effects, working methods with solutions and key performance indicators need to be found. Smaller enterprises in the wood industry have been identified as actors suffering from the consequential effects. Purpose: The purpose of the paper is to identify negative consequential effects experienced by smaller enterprises regarding the securing of limited resources. In addition, the aim is to describe a working method with solutions and associated key performance indicators to counteract the consequential effects regarding the securing of limited resources. Research questions: RQ1: What consequences do smaller enterprises experience when securing limited material?RQ2: What solutions and key performance indicators can be applied to counteract identified consequential effects when securing limited material for smaller enterprises?Method: The paper uses a deductive approach while applying a qualitative research method with elements of quantitative data. The primary empirical data was collected by unstructured and semistructured interviews, observations and the in-depth method focus-group interviews. Results: The study shows multiple consequential effects of not being able to secure limited resources as a smaller enterprise. The three major findings were: uncertainty in supply, decreased purchasing power due to being a smaller enterprise in the industry, and being forced to import materials. The study finds working methods with solutions and associated key performance indicators to counteract each effect. With supply chain resilience the effects of uncertainty in supply decreases. The purchasing power could increase by developing supplier relationships or increase the purchase price. By outsourcing a part of or the whole production process the effects of being forced to import could be counteracted. The key performance indicators for each solution needs to be developed individually for every company and should focus on critical moments related to the consequential effects.   Keywords: Limited resources, smaller enterprises, securing resources, consequential effects, solutions, key performance indicators, KPI, sourcingprocess, purchasing power, resilience, supply chain, supplier relationships, outsourcing, supplier pool, the wood industry, oak, oak log
769

Transmit and Receive Signal Processing for MIMO Terrestrial Broadcast Systems

Vargas Paredero, David Eduardo 17 June 2016 (has links)
[EN] Multiple-Input Multiple-Output (MIMO) technology in Digital Terrestrial Television (DTT) networks has the potential to increase the spectral efficiency and improve network coverage to cope with the competition of limited spectrum use (e.g., assignment of digital dividend and spectrum demands of mobile broadband), the appearance of new high data rate services (e.g., ultra-high definition TV - UHDTV), and the ubiquity of the content (e.g., fixed, portable, and mobile). It is widely recognised that MIMO can provide multiple benefits such as additional receive power due to array gain, higher resilience against signal outages due to spatial diversity, and higher data rates due to the spatial multiplexing gain of the MIMO channel. These benefits can be achieved without additional transmit power nor additional bandwidth, but normally come at the expense of a higher system complexity at the transmitter and receiver ends. The final system performance gains due to the use of MIMO directly depend on physical characteristics of the propagation environment such as spatial correlation, antenna orientation, and/or power imbalances experienced at the transmit aerials. Additionally, due to complexity constraints and finite-precision arithmetic at the receivers, it is crucial for the overall system performance to carefully design specific signal processing algorithms. This dissertation focuses on transmit and received signal processing for DTT systems using MIMO-BICM (Bit-Interleaved Coded Modulation) without feedback channel to the transmitter from the receiver terminals. At the transmitter side, this thesis presents investigations on MIMO precoding in DTT systems to overcome system degradations due to different channel conditions. At the receiver side, the focus is given on design and evaluation of practical MIMO-BICM receivers based on quantized information and its impact in both the in-chip memory size and system performance. These investigations are carried within the standardization process of DVB-NGH (Digital Video Broadcasting - Next Generation Handheld) the handheld evolution of DVB-T2 (Terrestrial - Second Generation), and ATSC 3.0 (Advanced Television Systems Committee - Third Generation), which incorporate MIMO-BICM as key technology to overcome the Shannon limit of single antenna communications. Nonetheless, this dissertation employs a generic approach in the design, analysis and evaluations, hence, the results and ideas can be applied to other wireless broadcast communication systems using MIMO-BICM. / [ES] La tecnología de múltiples entradas y múltiples salidas (MIMO) en redes de Televisión Digital Terrestre (TDT) tiene el potencial de incrementar la eficiencia espectral y mejorar la cobertura de red para afrontar las demandas de uso del escaso espectro electromagnético (e.g., designación del dividendo digital y la demanda de espectro por parte de las redes de comunicaciones móviles), la aparición de nuevos contenidos de alta tasa de datos (e.g., ultra-high definition TV - UHDTV) y la ubicuidad del contenido (e.g., fijo, portable y móvil). Es ampliamente reconocido que MIMO puede proporcionar múltiples beneficios como: potencia recibida adicional gracias a las ganancias de array, mayor robustez contra desvanecimientos de la señal gracias a la diversidad espacial y mayores tasas de transmisión gracias a la ganancia por multiplexado del canal MIMO. Estos beneficios se pueden conseguir sin incrementar la potencia transmitida ni el ancho de banda, pero normalmente se obtienen a expensas de una mayor complejidad del sistema tanto en el transmisor como en el receptor. Las ganancias de rendimiento finales debido al uso de MIMO dependen directamente de las características físicas del entorno de propagación como: la correlación entre los canales espaciales, la orientación de las antenas y/o los desbalances de potencia sufridos en las antenas transmisoras. Adicionalmente, debido a restricciones en la complejidad y aritmética de precisión finita en los receptores, es fundamental para el rendimiento global del sistema un diseño cuidadoso de algoritmos específicos de procesado de señal. Esta tesis doctoral se centra en el procesado de señal, tanto en el transmisor como en el receptor, para sistemas TDT que implementan MIMO-BICM (Bit-Interleaved Coded Modulation) sin canal de retorno hacia el transmisor desde los receptores. En el transmisor esta tesis presenta investigaciones en precoding MIMO en sistemas TDT para superar las degradaciones del sistema debidas a diferentes condiciones del canal. En el receptor se presta especial atención al diseño y evaluación de receptores prácticos MIMO-BICM basados en información cuantificada y a su impacto tanto en la memoria del chip como en el rendimiento del sistema. Estas investigaciones se llevan a cabo en el contexto de estandarización de DVB-NGH (Digital Video Broadcasting - Next Generation Handheld), la evolución portátil de DVB-T2 (Second Generation Terrestrial), y ATSC 3.0 (Advanced Television Systems Commitee - Third Generation) que incorporan MIMO-BICM como clave tecnológica para superar el límite de Shannon para comunicaciones con una única antena. No obstante, esta tesis doctoral emplea un método genérico tanto para el diseño, análisis y evaluación, por lo que los resultados e ideas pueden ser aplicados a otros sistemas de comunicación inalámbricos que empleen MIMO-BICM. / [CA] La tecnologia de múltiples entrades i múltiples eixides (MIMO) en xarxes de Televisió Digital Terrestre (TDT) té el potencial d'incrementar l'eficiència espectral i millorar la cobertura de xarxa per a afrontar les demandes d'ús de l'escàs espectre electromagnètic (e.g., designació del dividend digital i la demanda d'espectre per part de les xarxes de comunicacions mòbils), l'aparició de nous continguts d'alta taxa de dades (e.g., ultra-high deffinition TV - UHDTV) i la ubiqüitat del contingut (e.g., fix, portàtil i mòbil). És àmpliament reconegut que MIMO pot proporcionar múltiples beneficis com: potència rebuda addicional gràcies als guanys de array, major robustesa contra esvaïments del senyal gràcies a la diversitat espacial i majors taxes de transmissió gràcies al guany per multiplexat del canal MIMO. Aquests beneficis es poden aconseguir sense incrementar la potència transmesa ni l'ample de banda, però normalment s'obtenen a costa d'una major complexitat del sistema tant en el transmissor com en el receptor. Els guanys de rendiment finals a causa de l'ús de MIMO depenen directament de les característiques físiques de l'entorn de propagació com: la correlació entre els canals espacials, l'orientació de les antenes, i/o els desequilibris de potència patits en les antenes transmissores. Addicionalment, a causa de restriccions en la complexitat i aritmètica de precisió finita en els receptors, és fonamental per al rendiment global del sistema un disseny acurat d'algorismes específics de processament de senyal. Aquesta tesi doctoral se centra en el processament de senyal tant en el transmissor com en el receptor per a sistemes TDT que implementen MIMO-BICM (Bit-Interleaved Coded Modulation) sense canal de tornada cap al transmissor des dels receptors. En el transmissor aquesta tesi presenta recerques en precoding MIMO en sistemes TDT per a superar les degradacions del sistema degudes a diferents condicions del canal. En el receptor es presta especial atenció al disseny i avaluació de receptors pràctics MIMO-BICM basats en informació quantificada i al seu impacte tant en la memòria del xip com en el rendiment del sistema. Aquestes recerques es duen a terme en el context d'estandardització de DVB-NGH (Digital Video Broadcasting - Next Generation Handheld), l'evolució portàtil de DVB-T2 (Second Generation Terrestrial), i ATSC 3.0 (Advanced Television Systems Commitee - Third Generation) que incorporen MIMO-BICM com a clau tecnològica per a superar el límit de Shannon per a comunicacions amb una única antena. No obstant açò, aquesta tesi doctoral empra un mètode genèric tant per al disseny, anàlisi i avaluació, per la qual cosa els resultats i idees poden ser aplicats a altres sistemes de comunicació sense fils que empren MIMO-BICM. / Vargas Paredero, DE. (2016). Transmit and Receive Signal Processing for MIMO Terrestrial Broadcast Systems [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/66081 / Premios Extraordinarios de tesis doctorales
770

Om informationstekniskt bevis

Ekfeldt, Jonas January 2016 (has links)
Information technology evidence consists of a mix of representations of various applications of digital electronic equipment, and can be brought to the fore in all contexts that result in legal decisions. The occurrence of such evidence in legal proceedings, and other legal decision-making, is a phenomenon previously not researched within legal science in Sweden. The thesis examines some of the consequences resulting from the occurrence of information technology evidence within Swedish practical legal and judicial decision-making. The thesis has three main focal points. The first consists of a broad identification of legal problems that information technology evidence entails. The second focal point examines the legal terminology associated with information technology evidence. The third focal point consists of identifying sources of error pertaining to information technology evidence from the adjudicator’s point of view. The examination utilizes a Swedish legal viewpoint from a perspective of the public trust in courts. Conclusions include a number of legal problems in several areas, primarily in regards to the knowledge of the adjudicator, the qualification of different means of evidence and the consequences of representational evidence upon its evaluation. In order to properly evaluate information technology evidence, judges are – to a greater extent than for other types of evidence – in need of (objective) knowledge supplementary to that provided by parties and their witnesses and experts. Furthermore, the current Swedish evidence terminology has been identified as a complex of problems in and of itself. The thesis includes suggestions on certain additions to this terminology. Several sources of error have been identified as being attributable to different procedures associated with the handling of information technology evidence, in particular in relation to computer forensic investigations. There is a general need for future research focused on matters regarding both standards of proof for and evaluation of information technology evidence. In addition, a need for deeper legal scientific studies aimed at evidence theory has been identified, inter alia regarding the extent to which frequency theories are applicable in respect to information technology evidence. The need for related further discussions on future emerging areas such as negative evidence and predictive evidence are foreseen.

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