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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.
591

Investigating the Influence of Herd Behavior on Protection Motivation: A Multi-Stage Experiment

Vedadi, Ali 10 August 2018 (has links)
IT users often make security-related decisions in complex and multidimensional environments. Over-reliance on current behavioral security theories (e.g. Protection Motivation Theory) that do not account for such circumstances can seriously limit researchers’ ability to comprehend such decision making. In this regard, herd behavior theory explains that when individuals make decisions in uncertain circumstances, they may observe what other people are doing, discount their own limited information and imitate others (also known as social learning). Explaining protection motivation behavior from a different theoretical perspective (i.e. herd behavior) is one of the primary contributions of this study. Investigating whether protection motivation behaviors influenced by herd mentality can impact continuous secure behavior, as a very important and understudied information security phenomenon, is the other contribution of this study. In other words, examining whether security behaviors can be influenced by herd-related factors in uncertain circumstances, as well as whether such behaviors persist over time, is central to this study. The findings of this research show that in uncertain circumstances and when there is awareness about the widespread use of a certain security technology, users develop a significantly higher protection motivation. Furthermore, the results show that at the postoption stage, users tend to heavily rely on their own information and disregard the herd-related factors.
592

Investigating the Impact of Electronic Prescribing System User Interface Design on Prescribing Accuracy

Wiercioch, Wojtek January 2014 (has links)
Background: Electronic prescribing systems are designed to aid in the complex process of prescribing by providing patient information and decision support at the point of care. Successful implementation and effectiveness depend on a variety of factors, including usability and user interface design, which influence how the information and decision support are relayed to users. Poorly designed systems have been found to be associated with medication errors. Methods: We conducted a factorial design study to investigate the impact of screen density, highlighting, and placement of information, on the accuracy of prescribing when using an e-prescribing system. Study sessions were held during clinical pharmacology educational rounds, where residents and medical students answered simulated prescribing scenarios presented on various e-prescribing system interface configurations. Assignment of prescribing scenarios to interface configurations and presentation order were randomized between study sessions. Participants were also asked about their preferences for specific user interface configurations. Results: A total of 66 participants completed 844 prescribing cases, with 583 (69%) cases answered correctly. The presence of highlighting was associated with correct prescribing decisions (p-value = 0.001), with 181 out of 250 (72.4%) prescribing scenarios answered correctly on interfaces with highlighting of key clinical information, as opposed to 156 out of 242 (64.5%) on interface configurations without. Low screen density and central placement of information were not found to be statistically significant predictors of prescribing accuracy. The presence of highlighting was the only factor that the majority of participants (80.3%) preferred, but no effect was found when comparing prescribing accuracy on preferred versus non-preferred interface configurations. Conclusions: The factorial design methodology developed is a novel approach for efficient and objective evaluation of multiple user interface design factors in one study. Evidence-based design and usability principles are needed to enhance the design and appropriate use of e-prescribing systems as usability problems continue to be one of the primary reasons for dissatisfaction and poor levels of adoption. / Thesis / Master of Science (MSc)
593

Differential cross section measurement and phase shift analysis for Σ⁺p elastic scattering / Σ⁺p弾性散乱の微分断面積測定および位相差解析

Nanamura, Takuya 23 March 2023 (has links)
京都大学 / 新制・課程博士 / 博士(理学) / 甲第24408号 / 理博第4907号 / 新制||理||1701(附属図書館) / 京都大学大学院理学研究科物理学・宇宙物理学専攻 / (主査)教授 永江 知文, 准教授 成木 恵, 教授 橋本 幸士 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM
594

Ad Hoc Information Extraction in a Clinical Data Warehouse with Case Studies for Data Exploration and Consistency Checks / Ad Hoc Informationsextraktion in einem Klinischen Data-Warehouse mit Fallstudien zur Datenexploration und Konsistenzüberprüfungen

Dietrich, Georg January 2019 (has links) (PDF)
The importance of Clinical Data Warehouses (CDW) has increased significantly in recent years as they support or enable many applications such as clinical trials, data mining, and decision making. CDWs integrate Electronic Health Records which still contain a large amount of text data, such as discharge letters or reports on diagnostic findings in addition to structured and coded data like ICD-codes of diagnoses. Existing CDWs hardly support features to gain information covered in texts. Information extraction methods offer a solution for this problem but they have a high and long development effort, which can only be carried out by computer scientists. Moreover, such systems only exist for a few medical domains. This paper presents a method empowering clinicians to extract information from texts on their own. Medical concepts can be extracted ad hoc from e.g. discharge letters, thus physicians can work promptly and autonomously. The proposed system achieves these improvements by efficient data storage, preprocessing, and with powerful query features. Negations in texts are recognized and automatically excluded, as well as the context of information is determined and undesired facts are filtered, such as historical events or references to other persons (family history). Context-sensitive queries ensure the semantic integrity of the concepts to be extracted. A new feature not available in other CDWs is to query numerical concepts in texts and even filter them (e.g. BMI > 25). The retrieved values can be extracted and exported for further analysis. This technique is implemented within the efficient architecture of the PaDaWaN CDW and evaluated with comprehensive and complex tests. The results outperform similar approaches reported in the literature. Ad hoc IE determines the results in a few (milli-) seconds and a user friendly GUI enables interactive working, allowing flexible adaptation of the extraction. In addition, the applicability of this system is demonstrated in three real-world applications at the Würzburg University Hospital (UKW). Several drug trend studies are replicated: Findings of five studies on high blood pressure, atrial fibrillation and chronic renal failure can be partially or completely confirmed in the UKW. Another case study evaluates the prevalence of heart failure in inpatient hospitals using an algorithm that extracts information with ad hoc IE from discharge letters and echocardiogram report (e.g. LVEF < 45 ) and other sources of the hospital information system. This study reveals that the use of ICD codes leads to a significant underestimation (31%) of the true prevalence of heart failure. The third case study evaluates the consistency of diagnoses by comparing structured ICD-10-coded diagnoses with the diagnoses described in the diagnostic section of the discharge letter. These diagnoses are extracted from texts with ad hoc IE, using synonyms generated with a novel method. The developed approach can extract diagnoses from the discharge letter with a high accuracy and furthermore it can prove the degree of consistency between the coded and reported diagnoses. / Die Bedeutung von Clinical Data Warehouses (CDW) hat in den letzten Jahren stark zugenommen, da sie viele Anwendungen wie klinische Studien, Data Mining und Entscheidungsfindung unterstützen oder ermöglichen. CDWs integrieren elektronische Patientenakten, die neben strukturierten und kodierten Daten wie ICD-Codes von Diagnosen immer noch sehr vielen Textdaten enthalten, sowie Arztbriefe oder Befundberichte. Bestehende CDWs unterstützen kaum Funktionen, um die in den Texten enthaltenen Informationen zu nutzen. Informationsextraktionsmethoden bieten zwar eine Lösung für dieses Problem, erfordern aber einen hohen und langen Entwicklungsaufwand, der nur von Informatikern durchgeführt werden kann. Außerdem gibt es solche Systeme nur für wenige medizinische Bereiche. Diese Arbeit stellt eine Methode vor, die es Ärzten ermöglicht, Informationen aus Texten selbstständig zu extrahieren. Medizinische Konzepte können ad hoc aus Texten (z. B. Arztbriefen) extrahiert werden, so dass Ärzte unverzüglich und autonom arbeiten können. Das vorgestellte System erreicht diese Verbesserungen durch effiziente Datenspeicherung, Vorverarbeitung und leistungsstarke Abfragefunktionen. Negationen in Texten werden erkannt und automatisch ausgeschlossen, ebenso wird der Kontext von Informationen bestimmt und unerwünschte Fakten gefiltert, wie z. B. historische Ereignisse oder ein Bezug zu anderen Personen (Familiengeschichte). Kontextsensitive Abfragen gewährleisten die semantische Integrität der zu extrahierenden Konzepte. Eine neue Funktion, die in anderen CDWs nicht verfügbar ist, ist die Abfrage numerischer Konzepte in Texten und sogar deren Filterung (z. B. BMI > 25). Die abgerufenen Werte können extrahiert und zur weiteren Analyse exportiert werden. Diese Technik wird innerhalb der effizienten Architektur des PaDaWaN-CDW implementiert und mit umfangreichen und aufwendigen Tests evaluiert. Die Ergebnisse übertreffen ähnliche Ansätze, die in der Literatur beschrieben werden. Ad hoc IE ermittelt die Ergebnisse in wenigen (Milli-)Sekunden und die benutzerfreundliche Oberfläche ermöglicht interaktives Arbeiten und eine flexible Anpassung der Extraktion. Darüber hinaus wird die Anwendbarkeit dieses Systems in drei realen Anwendungen am Universitätsklinikum Würzburg (UKW) demonstriert: Mehrere Medikationstrendstudien werden repliziert: Die Ergebnisse aus fünf Studien zu Bluthochdruck, Vorhofflimmern und chronischem Nierenversagen können in dem UKW teilweise oder vollständig bestätigt werden. Eine weitere Fallstudie bewertet die Prävalenz von Herzinsuffizienz in stationären Patienten in Krankenhäusern mit einem Algorithmus, der Informationen mit Ad-hoc-IE aus Arztbriefen, Echokardiogrammbericht und aus anderen Quellen des Krankenhausinformationssystems extrahiert (z. B. LVEF < 45). Diese Studie zeigt, dass die Verwendung von ICD-Codes zu einer signifikanten Unterschätzung (31%) der tatsächlichen Prävalenz von Herzinsuffizienz führt. Die dritte Fallstudie bewertet die Konsistenz von Diagnosen, indem sie strukturierte ICD-10-codierte Diagnosen mit den Diagnosen, die im Diagnoseabschnitt des Arztbriefes beschriebenen, vergleicht. Diese Diagnosen werden mit Ad-hoc-IE aus den Texten gewonnen, dabei werden Synonyme verwendet, die mit einer neuartigen Methode generiert werden. Der verwendete Ansatz kann Diagnosen mit hoher Genauigkeit aus Arztbriefen extrahieren und darüber hinaus den Grad der Übereinstimmung zwischen den kodierten und beschriebenen Diagnosen bestimmen.
595

Der Einfluss von Alter und Ängstlichkeit auf die Furchtgeneralisierung und die Aufmerksamkeitslenkung bei gesunden Kindern und Jugendlichen / The influence of age and anxiety on fear generalization and attentional processes in healthy children and adolescents

Daub, Jonas January 2023 (has links) (PDF)
Mittels einer klinischen Studie wurden die Furchtgeneralisierung und Aufmerksamkeitslenkung von 44 gesunden Kindern und Jugendlichen im Alter von 9-17 Jahren untersucht. Eine Übergeneralisierung konditionierter Furcht sowie veränderte Aufmerksamkeitsprozesse werden in zahlreichen Arbeiten mit der Entstehung und Aufrechterhaltung von Angsterkrankungen in Verbindung gebracht. Der Hauptteil der Forschung beschränkte sich bislang auf die Untersuchung von erwachsenen Probanden. Da Angsterkrankungen jedoch häufig bereits im Kindes- und Jugendalter entstehen und sich in der Erforschung psychiatrischer Erkrankungen zunehmend eine dimensionale Betrachtungsweise durchsetzt, bestand das Ziel der Studie darin, etwaige Alterseffekte und den Einfluss der Ängstlichkeit auf die genannten Phänomene bei gesunden Probanden zu untersuchen. Darüber hinaus wurde ein potentiell präventiver Ansatz erforscht. Im Ergebnis zeigten sich in den Gruppenvergleichen keine relevanten Differenzen. Interessanterweise deutete sich in der Gruppe der älteren Probanden entgegen der Erwartung eine verstärkte Furchtgeneralisierung an, die womöglich mit einer veränderten Beziehung zu Furcht und Risiko in der Adoleszenz zusammenhängt. Aus den Befunden ergibt sich die Notwendigkeit weiterer, prospektiver Arbeiten, um unser Verständnis der Ätiologie von Angsterkrankungen zu verbessern. Weiterhin ist noch offen, inwiefern es sich bei der Übergeneralisierung und einer veränderten Aufmerksamkeitslenkung um Risikofaktoren für die Entwicklung von Angsterkrankungen oder vielmehr um Epiphänomene handelt, die erst mit Ausbruch der Erkrankung auftreten. Der Einsatz von Methoden der virtuellen Realität erscheint besonders geeignet, diese Prozesse zukünftig noch besser zu erforschen. / In this clinical study fear generalization and attentional processes have been investigated in 44 healthy children and adolescents aged 9-17 years. Overgeneralization of conditioned fear and altered attentional processes have been linked to the development and maintenance of anxiety disorders in numerous studies. The majority of research to date has been limited to the study of adult subjects. However, since anxiety disorders often develop in childhood and adolescence and a dimensional approach has become increasingly important in the study of psychiatric disorders, the aim of the study was to investigate age effects and the influence of anxiety on the aforementioned phenomena in healthy subjects. In addition, a potential preventive approach has been studied. The results showed no relevant differences in the group comparisons. Interestingly and contrary to expectations, there was a trend for increased fear generalization in the group of older subjects, which can possibly be related to a changed relationship to fear and risk in adolescence. The findings suggest the need for further, prospective work to improve our understanding of the aetiology of anxiety disorders. Furthermore, it is still open to what extent overgeneralization and altered attentional processes are risk factors for the development of anxiety disorders or rather epiphenomena that only appear with the onset of the disorder. The use of virtual reality methods seems particularly suitable for researching these processes even better in the future.
596

Experimental Investigation on Cooling Performance of Additively Manufactured Channels

Firat, Mehmet Deniz January 2022 (has links)
No description available.
597

Ranking images based on image aesthetics using a neural network

Olsson, Daniel January 2018 (has links)
How humans perceive image quality in general (e.g. aesthetics, resolution, lighting) and what constitutes to an image of good quality and aesthetics, is an interesting topic for neural networks to tackle. Lately several different aspects have been investigated in theory to try and build models to accurately predict the quality of an image. The problem is investigated in this thesis by performing an experiment and testing a method that computes the aesthetic value of an image and ranks a number of images according to their aesthetic value. The rankings are then compared to human rankings of the same images to determine if there is a correlation between the two. From the results the null hypothesis (that the correlation is just a coincidence) cannot be rejected but in 92% of the cases there were at least some agreement (same image, same position) between the algorithm and the human ranking. There are multiple similarities between the human rankings and the algorithm rankings which reveals a good potential to further investigate the problem in future. / Hur bildkvalité generellt sett uppfattas av människor (så som estetik, upplösning, ljussättning) och vad som gör att en bild kan klassificeras som en bild av hög kvalité är ett intressant ämnesområde för neurala nätverk. Den senaste forskningen visar att det finns flera metoder och aspekter som påverkar hur kvalitativ en bild är i teorin. Problemet undersöks i denna rapport med ett experiment och metoden som testas är en metod som kan sätta ett estetiskt värde på en bild. Tillsammans med flera olika bilder kunde en rangordning skapas. Denna rangordning jämfördes sedan med en rangordning skapad av människor. Från resultaten så kan inte nollhypotesen förkastas (att korrelationen är ett sammanträffande) men att i 92% av fallen så finns det åtminstånde en likhet mellan algoritmens rangordning och en människas rangordning. Det finns flera likheter mellan de mänskliga rangordningarna och algoritmens rangordning vilket visar en god potential för forsatt undersökning i framtiden.
598

Possibilities for removal of micropollutants in small-scale wastewater treatment - methods and multi-criteria analysis

Li, Anqi January 2018 (has links)
The quality of worlds’ water resources is facing new challenges, for instance detectable concentration of various trace contaminants under the term micropollutants is discharging into water bodies from both municipal wastewater treatment plants and from on-site wastewater facilities. A project called RedMic aim at identifying and quantifying emissions of micropollutants from on-site wastewater treatments as a basis for providing innovative treatment technologies to reduce potential risks for groundwater and surface water contamination. This thesis work deals with two of the work packages in the RedMic project: a column experiment to test the capability of 10 adsorbents to remove micropollutants and a multi-criteria analysis is conducted to evaluate if a filter composed of granulated activated carbon (GAC) or ozonation can be used for on-site wastewater treatment facilities. Based on the removal efficiency of dissolved organic carbon (DOC) of selected adsorbents, two types of activated carbon reduced up to 90% DOC concentration in the effluents. Moreover, six other adsorbents also showed good removal efficiency with around 60% in the second sampling. However, the data used in this thesis was only from the initial part of the experiment that continued and the final results will be published elsewhere. Two system solutions were evaluated with multi-criteria analysis: sandbed filter with either GAC filtration (1) or with ozonation (2) System solution 1 was found to have advantage compared to system 2.
599

Investigation of Factors Affecting the Emulsification of Skin Creams / Undersökning av faktorer som påverkar emulgeringen av hudkrämer

Bodell, Linnéa January 2019 (has links)
Skin creams are one of Sky Resources key products, they are produced as an oil-in-water(O/W) emulsion. In order to form an emulsion the oil and water needs to be able to mixtogether, for that to happen the oil and water droplets have to be broken up into very smalldroplets (colloids). There is a certain quality difference between the products from the research and developmentdepartment and the production department. The skin creams have been made through a given recipe, which contains a number of chemicalformulas. Tests have been preformed and the results have been examined. The creams werefirst made in the research and development department’s laboratory and then that small scaleproduction was taken to big scale production in the production department. The results havebeen documented and the parameters that have been examined are speed, temperature and timeto see how they affect the viscosity of the creams. A factorial experiment with three factors has been made. The factors are the time the skincream is homogenized, at what speed the cream is homogenized and at what temperature thephases are when the homogenizing is started. That gives a total of 8 creams from thelaboratory level. The viscosity of the skin creams have been measured after 10 minutes, 24 hours, 48 hours and1 week to see how it is increasing with time and if it is increasing at all or perhaps decreasing.After 1 week the creams were also studied under a microscope to see how successful theemulsions were with different factors. The fourth cream was the only cream from the laboratory that had a successful emulsion andstabilized viscosity. So the factors that are brought from laboratory to production is highhomogenization time, high homogenization speed and low temperature. Two differenthomogenizers were tried in production. The factor that affects the viscosity the most seems to be the temperature. After these tests,there is still a difference between the products from the research and development departmentand the production department even with the lower temperatures on the oil and water phases.The second cream from production and cream 4 from the laboratory show the smallest qualitydifference. More tests need to be done in the production department with differenthomogenization speed and time with the lower temperature to establish the result. / Hudkrämer är en av Sky Resources viktigaste produkter, de produceras som en olja-i-vattenemulsion(O/W). För att bilda en emulsion måste oljan och vattnet kunna blandas och för attdet ska hända måste olje- och vattendropparna brytas upp i mycket små droppar (kolloider). Det finns en viss kvalitetsskillnad mellan produkterna från forsknings- ochutvecklingsavdelningen och produktionsavdelningen. Hudkrämerna har gjorts genom ett givet recept, som innehåller ett antal kemiska ingredienser. Tester har utformats och resultaten har undersökts. Krämerna gjordes först i forsknings- ochutvecklingsavdelningen laboratorium och sedan togs den småskaliga produktionen tillstorskalig produktion i produktionsavdelningen. Resultaten har dokumenterats ochparametrarna som har undersökts är hastighet, temperatur och tid för att se hur de påverkarviskositeten hos krämerna. Ett faktorförsök med tre faktorer har gjorts. Faktorerna som använts är den tid hudkrämenhomogeniseras, i vilken hastighet krämen homogeniseras och vid vilken temperatur faserna ärnär homogeniseringen startas. Det ger totalt 8 krämer från laboratorienivån. Viskositeten hos hudkrämerna mättes efter 10 minuter, 24 timmar, 48 timmar och 1 vecka föratt se hur den ändras med tiden. Efter 1 vecka studerades också krämerna under ett mikroskopför att se hur lyckad emulsionerna var med olika faktorer. Den fjärde krämen var den enda krämen från laboratoriet som hade en lyckad emulsion och enstabil viskositet. Så de faktorer som tas från laboratorium till produktion är höghomogeniseringstid, hög homogeniseringshastighet och låg temperatur. Försök gjordes i tvåhomogenisatorer i produktionen. Den faktor som påverkar viskositeten mest är temperaturen. Efter dessa tester finns det dockfortfarande skillnader mellan produkterna från forsknings- och utvecklingsavdelningen ochproduktionsavdelningen, även med de lägre temperaturerna på olje- och vattenfaserna. Denandra krämen från produktion och kräm 4 från laboratoriet visar den minstakvalitetsskillnaden. Fler test måste göras i produktionsavdelningen med olikahomogeniseringshastigheter och tider med den lägre temperaturen för att fastställa resultatet.
600

NO-experiment som hemuppgift - en studie bland tvåspråkiga elever

Bengtsson, Peter January 2004 (has links)
Denna studies syfte var dels att undersöka om experiment som hemuppgift underlättar förtvåspråkiga elever att förstå naturvetenskap dels att undersöka om dessa upplever att no-hemuppgiftens utformning påverkar deras möjligheter att bättre klara av hemuppgiften. Elever i årskurs 5 intervjuades vid två tillfällen, före och efter att de fått experimentera dels i hemmet med någon vuxen dels i skolan med andra elever i smågrupper. Undersökningen visar att en majoritet av eleverna föredrar att få experiment som hemuppgift framför en faktatext som behandlar experimenten som de gjort i skolan. Så gott som samtliga av de intervjuade eleverna uttryckte glädje över att få göra experimenten hemma. Eleverna visade vid det andra intervjutillfället ökad förståelse för de naturvetenskapliga begrepp, som behandlades iundersökningen. Det gick dock inte att avgöra vilken typ av no-hemuppgift som gynnadeförståelsen mest.

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