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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.
211

Crowdsourced traffic information in traffic management : Evaluation of traffic information from Waze

Lenkei, Zsolt January 2018 (has links)
The early observation and elimination of non-recurring incidents is a crucial task in trafficmanagement. The performance of the conventional incident detection methods (trafficcameras and other sensory technologies) is limited and there are still challenges inobtaining an accurate picture of the traffic conditions in real time. During the last decade,the technical development of mobile platforms and the growing online connectivity made itpossible to obtain traffic information from social media and applications based on spatialcrowdsourcing. Utilizing the benefits of crowdsourcing, traffic authorities can receiveinformation about a more comprehensive number of incidents and can monitor areaswhich are not covered by the conventional incident detection systems. The crowdsourcedtraffic data can provide supplementary information for incidents already reported throughother sources and it can contribute to earlier detection of incidents, which can lead tofaster response and clearance time. Furthermore, spatial crowdsourcing can help to detectincident types, which are not collected systematically yet (e.g. potholes, traffic light faults,missing road signs). However, before exploiting crowdsourced traffic data in trafficmanagement, numerous challenges need to be resolved, such as verification of the incidentreports, predicting the severity of the crowdsourced incidents and integration with trafficdata obtained from other sources.During this thesis, the possibilities and challenges of utilizing spatial crowdsourcingtechnologies to detect non-recurring incidents were examined in form of a case study.Traffic incident alerts obtained from Waze, a navigation application using the concept ofcrowdsourcing, were analyzed and compared with officially verified incident reports inStockholm. The thesis provides insight into the spatial and temporal characteristics of theWaze data. Moreover, a method to identify related Waze alerts and to determine matchingincident reports from different sources is presented. The results showed that the number ofreported incidents in Waze is 4,5 times higher than the number of registered incidents bythe Swedish authorities. Furthermore, 27,5 % of the incidents could have been detectedfaster by using the traffic alerts from Waze. In addition, the severity of Waze alerts isexamined depending on the attributes of the alerts.
212

Crowdsourced traffic information in traffic management : Evaluation of traffic information from Waze

Lenkei, Zsolt January 2018 (has links)
The early observation and elimination of non-recurring incidents is a crucial task in traffic management. The performance of the conventional incident detection methods (traffic cameras and other sensory technologies) is limited and there are still challenges in obtaining an accurate picture of the traffic conditions in real time. During the last decade, the technical development of mobile platforms and the growing online connectivity made it possible to obtain traffic information from social media and applications based on spatial crowdsourcing. Utilizing the benefits of crowdsourcing, traffic authorities can receive information about a more comprehensive number of incidents and can monitor areas which are not covered by the conventional incident detection systems. The crowdsourced traffic data can provide supplementary information for incidents already reported through other sources and it can contribute to earlier detection of incidents, which can lead to faster response and clearance time. Furthermore, spatial crowdsourcing can help to detect incident types, which are not collected systematically yet (e.g. potholes, traffic light faults, missing road signs). However, before exploiting crowdsourced traffic data in traffic management, numerous challenges need to be resolved, such as verification of the incident reports, predicting the severity of the crowdsourced incidents and integration with traffic data obtained from other sources. During this thesis, the possibilities and challenges of utilizing spatial crowdsourcing technologies to detect non-recurring incidents were examined in form of a case study. Traffic incident alerts obtained from Waze, a navigation application using the concept of crowdsourcing, were analyzed and compared with officially verified incident reports in Stockholm. The thesis provides insight into the spatial and temporal characteristics of the Waze data. Moreover, a method to identify related Waze alerts and to determine matching incident reports from different sources is presented. The results showed that the number of reported incidents in Waze is 4,5 times higher than the number of registered incidents by the Swedish authorities. Furthermore, 27,5 % of the incidents could have been detected faster by using the traffic alerts from Waze. In addition, the severity of Waze alerts is examined depending on the attributes of the alerts.
213

Evolving Expert Knowledge Bases: Applications of Crowdsourcing and Serious Gaming to Advance Knowledge Development for Intelligent Tutoring Systems

Floryan, Mark 01 May 2013 (has links)
This dissertation presents a novel effort to develop ITS technologies that adapt by observing student behavior. In particular, we define an evolving expert knowledge base (EEKB) that structures a domain's information as a set of nodes and the relationships that exist between those nodes. The structure of this model is not the particularly novel aspect of this work, but rather the model's evolving behavior. Past efforts have shown that this model, once created, is useful for providing students with expert feedback as they work within our ITS called Rashi. We present an algorithm that observes groups of students as they work within Rashi, and collects student contributions to form an accurate domain level EEKB. We then present experimentation that simulates more than 15,000 data points of real student interaction and analyzes the quality of the EEKB models that are produced. We discover that EEKB models can be constructed accurately, and with significant efficiency compared to human constructed models of the same form. We are able to make this judgment by comparing our automatically constructed models with similar models that were hand crafted by a small team of domain experts. We also explore several tertiary effects. We focus on the impact that gaming and game mechanics have on various aspects of this model acquisition process. We discuss explicit game mechanics that were implemented in the source ITS from which our data was collected. Students who are given our system with game mechanics contribute higher amounts of data, while also performing higher quality work. Additionally, we define a novel type of game called a knowledge-refinement game (KRG), which motivates subject matter experts (SMEs) to contribute to an already constructed EEKB, but for the purpose of refining the model in areas in which confidence is low. Experimental work with the KRG provides strong evidence that: 1) the quality of the original EEKB was indeed strong, as validated by KRG players, and 2) both the quality and breadth of knowledge within the EEKB are increased when players use the KRG.
214

Crowdsourcing av data för Hybrid Code Networks

Linné, Christoffer, Olausson, Pontus January 2020 (has links)
Task-oriented dialogue systems are a popular way for organisations to generate extra value both internally and for customers. Modern approaches for these dialogue systems that use neural networks to enable training directly on written dialogues are very data hungry, which complicates their implementation. Crowdsourcing is an attractive solution for generating this type of training data, but the method also comes with several difficulties. We introduce a new method for generating training data based on parallel crowdsourcing of dialogues, as well as crowdsourced quality review. We use this method to collect a small dataset that takes place within the domain bus driver-traveler. We believe that this method offers an efficient way to collect new, high-quality datasets. Hybrid Code Networks is a model for dialogue systems that combines a neural network with domain-specific knowledge, and thus requires a significantly smaller amount of training data than other similar dialogue systems to achieve comparable performance. By combining Hybrid Code Networks with our new method for generating training data, we believe that the threshold for implementing task-oriented dialogue systems on domains with insufficient training data can be lowered. We implement Hybrid Code Networks and train the implementation on the collected dataset and achieve good results. / Uppgiftsorienterade dialogsystem är ett populärt sätt för företag att generera extra värde både internt och för kunder. Moderna modeller för dessa dialogsystem som använder neurala nätverk för att möjliggöra träning direkt på skriftliga dialoger är väldigt datahungriga, vilket försvårar implementationen av dessa. Crowdsourcing är en attraktiv lösning för att generera denna typ av träningsdata, men metoden kommer även med flera svårigheter. Vi introducerar en ny metod för generering av träningsdata som bygger på parallell crowdsourcing av dialoger, samt crowdsourcad kvalitetsgranskning. Vi använder denna metod för att samla in ett litet dataset som utspelar sig inom domänen busschaufför-resenär. Vi menar att denna metod erbjuder ett effektivt sätt att samla in nya, högkvalitativa dataset. Hybrid Code Networks är en modell för dialogsystem som kombinerar ett neuralt nätverk med domänspecifik kunskap, och som på så sätt kräver en betydligt mindre mängd träningsdata än andra liknande dialogsystem för att uppnå jämförbar prestanda. Genom att kombinera Hybrid Code Networks med vår nya metod för generering av träningsdata menar vi att man kan sänka tröskeln för att implementera uppgiftsorienterade dialogsystem på domäner med otillräcklig träningsdata. Vi implementerar Hybrid Code Networks och tränar implementationen på det insamlade datasetet, och uppnår goda resultat.
215

Mobile Crowd Instrumentation: Design of Surface Solar Irradiance Instrument

Singh, Abhishek 26 April 2017 (has links)
No description available.
216

Vox Populi: The Crowdsourced Building

Moyer, Craig E. 28 June 2016 (has links)
No description available.
217

DHT-based Collaborative Web Translation

Tu, Zongjie January 2016 (has links)
No description available.
218

“EXPERT” AND “NON-EXPERT” DECISION MAKING IN A PARTICIPATORY GAME SIMULATION: A FARMING SCENARIO IN ATHIENOU, CYPRUS

Massey, David 19 July 2012 (has links)
No description available.
219

Welche Einflussfaktoren eignen sich für die Typisierung von Radfahrer*innen mittels GPS-Daten? Ein Ansatz zur Kalibrierung von Self-Selected-Samples

Lißner, Sven 07 March 2022 (has links)
Für eine zielgerichtete Radverkehrsplanung sind Analysedaten notwendig, die aber in vielen Kommunen kaum verfügbar sind. GPS - Daten von Radfahrer*innen können diese Datenlücke schließen. Bestehende Datensätze und Forschungsansätze bleiben bis-her den Nachweis der Repräsentativität für die Grundgesamtheit der Radfahrer*innen im jeweiligen Untersuchungsgebiet schuldig. Oft wird dies zudem als Schwachpunkt bisheriger Arbeiten thematisiert. Um die Frage der Repräsentativität von GPS – Datensätzen für den deutschen Raum zu untersuchen, wird in der vorliegenden Arbeit das Radverkehrsverhalten von Radfahrer*innen im Raum Dresden analysiert. Grundlage der Analyse ist ein im Rahmen des Forschungsprojektes „RadVerS“ erhobener GPS-Datensatz von 200 Proband*innen, der 5.300 Einzelwege im Untersuchungsgebiet der Stadt Dresden enthält und Einblicke in deren Radverkehrsverhalten erlaubt. Die erhobenen Daten wurden mit unterschiedlichen Verfahren aufbereitet, so wurden beispielsweise Fahrten mit anderen Verkehrsmodi entfernt und Fahrten in einzelne Wege aufgeteilt. Anschließend wurden die Wegedaten mit Daten aus dem Verkehrsnetz des Untersuchungsgebietes angereichert und statistisch ausgewertet. Der Einfluss einzelner Fahrverhaltensparameter wurde dabei sowohl deskriptiv als auch mittels eines generalisierten linearen Modells ausgewertet. Das Ergebnis der Untersuchungen zeigt, dass folgende Attribute Einfluss auf das Rad-verkehrsverhalten aufweisen und somit maßgeblich die Diskussion über die Repräsentativität von GPS Daten für die Radverkehrsplanung bestimmen sollten. Dabei offenbaren sich Unterscheide zum Vorgehen bei Haushaltsbefragungen: - Alter: Es ist sicherzustellen, dass in der Stichprobe insbesondere sehr junge (< 30 Jahre) und ältere (>65 Jahre) Nutzer*innen entsprechend enthalten sind. Die Altersklassen zwischen 30 und 65 können dagegen zusammengefasst werden und sind i. d. R. ausreichend repräsentiert. - Geschlecht: Diejenigen weiblichen Teilnehmerinnen, welche in Smartphone-basierten Stichproben enthalten sind, bewegen sich auf dem Fahrrad mit langsameren Geschwindigkeiten als männliche Probanden. Zudem beschleunigen sie weniger stark und ihre zurückgelegten Entfernungen sind kürzer als die der männlichen Probanden. - Wegezweck: Die in smartphone-basierten Stichproben enthaltenen Arbeitswege sind tendenziell länger als Einkaufs- und Freizeitwege - Die auf Arbeitswegen gefahrenen Geschwindigkeiten sind zudem höher als bei den übrigen Wegezwecken Oben aufgeführte Parameter haben nur einen geringen und nicht signifikanten Einfluss auf die Infrastrukturnutzung durch Radfahrer*innen. So konnten nur geringe Unterschiede bei der Wahl der Infrastruktur zwischen Geschlechtern, unterschiedlichen Altersklassen und Radfahrtypen festgestellt werden. Darüber hinaus lässt sich feststellen, dass nach erfolgter Datenaufbereitung die Wege-weitenverteilung und der Tagesgang der Radfahrten im Wesentlichen kongruent zu den Ergebnissen von Haushaltsbefragungen wie beispielsweise Mobilität in Städten (SrV) sind.:1. Einleitung 1 1.1 Hintergrund 3 1.2 Aufgabenstellung 5 1.3 Vorgehen 6 1.4 Herausforderungen und Grenzen der gewählten Methodik 7 2. Grundlagen 10 2.1 Radverkehr in Deutschland 11 2.2 Kennwerte des Radverkehrs 13 2.3 Planungsdaten und Analysemethoden im Radverkehr 18 2.4 Crowdsourcing als neuer Ansatz in der Verkehrsplanung 23 2.5 Big Data 26 2.6 GPS als Erhebungswerkzeug 27 2.7 Zusammenfassung 31 3. Forschungsstand 33 3.1 Methodik der Literaturrecherche Definition von Schlagworten, Recherchedatenbanken 3.2 Crowdsourcing und GPS-Datennutzung in der Verkehrswissenschaft 35 3.3 Quantitative (GPS)-Studien zum Radverkehrsverhalten 40 3.4 Zusammenfassung 52 4. Methodik 55 4.1 Vorbereitung der Datenerhebung 57 4.2 Datenerhebung 58 4.3 Die Datenübertragung 67 4.4 Datenschutz 68 4.5 Parameterauswahl 69 4.6 Datenverarbeitung 70 4.7 Berechnung der Kennziffern für die Wegestatistik 99 4.8 Zusammenfassung 99 5. Ergebnisse 101 5.1 Allgemeine Kennzahlen 101 5.2 Deskriptive Statistik 109 5.3 Inferenzstatistik 128 5.4 Ergebnisse der Vergleichsstichprobe 144 5.5 Zusammenfassung der wesentlichen Ergebnisse 149 6. Diskussion 152 6.1 Zusammenfassung und Interpretation der zentralen Ergebnisse 152 6.2 Stärken und Schwächen der Arbeit 158 6.3 Grenzen der Methodik 162 6.4 Zusammenfassung 165 7. Fazit und Ausblick 168
220

Att snärja en potentiell folkmassa

Nilsson, Ida January 2012 (has links)
Webb 2.0 skapar idag förutsättningar för nya typer av webbtjänster som använder sig av viljansom vi användare, har till att delta och bidra. Crowdsourcing är ett samlingsbegrepp för huranvändare över hela världen kan skapa värde och inriktar sig på att få många individer attdelta. Det kan röra sig om att skapa en ny logotyp till ett företag, samla in pengar till ett projekteller kategorisera data.I denna empiriska studie granskar vi innehåll, instruktioner och funktioner på fyracrowdsourcingtjänster för att undersöka hur deltagare motiveras till att delta. Vi utgår frånKaufmanns m.fl. motivationsmodell som är framtagen just för crowdsourcingdeltagande ochmotivationen bakom deltagandet. Utifrån motivationsmodellen har frågor formulerats somanvänds för att granska tjänsternas innehåll. Vi tittar på skillnader och likheter mellancrowdsourcingtjänster som erbjuder möjlig monetär ersättning och de som inte gör det. Vi tittarockså på relevansen i Kaufmanns m.fl. motivationsmodell.Att titta på skillnader och likheter visar sig vara otillräckligt och resultaten visar istället treprimära mönster. Ej varierande faktorer, där motivationsfaktorerna används i sammautsträckning mellan och inom kategorierna. Dessa är generellt applicerbaramotivationsfaktorer, framför allt faktorerna utveckla personliga färdigheter och externavärderingar. I det andra mönstret, faktorer varierande med kategori, hittar vi likheter inom menskillnader mellan kategorierna. Där står motivationsfaktorn tidsfördriv ut från de andrafaktorerna. Faktorer varierande oberoende av kategori, är det tredje mönstret som beskriverskillnader både inom och mellan kategorierna. T.ex. används motivationsfaktorn attmarknadsföra sig på olika sätt av samtliga tjänster. Utöver detta finner vi också stöd förKaufmanns m.fl. motivationsmodell och slutligen bekräftas fynd från tidigare studier. / Web 2.0 creates opportunities for new sorts of Web services that take advantage of the user’swill to participate and contribute. Crowdsourcing allows users all over the world to be a part ofcreating value. It might involve creating a logo for a new business, raise funds for a project orcategorize data.In this empirical study, we examine the content, instructions and functions of fourcrowdsourcing services, to determine how the services are creating motivation and participation.In 2011 Kaufmann et al. published a motivation model for crowdsourcing participation thataims to explain motivation behind the participation. The model contains thirteen motivationalfactors that we in this study developed into thirteen questions. We use these questions toexamine the content of the crowdsourcing services. Primarily we search for differences andsimilarities between services that offer possible monetary compensation and those who don’toffer any possible monetary compensation. We also want to test the relevance of Kaufmann’s etal. motivation model.Differences and similarities is shown to be insufficient to describe the findings made in thisstudy. Instead we identified three patterns. The first one has similarities within and between thetwo categories, where the motivational factors, human capital advancement and actionsignificance by external values, showed to have the strongest connection to this pattern. Thesecond pattern we found similarities within but differences between the categories, showed thatthe motivational factor, pastime, differs the most between categories. The third pattern,differences within and between categories, is the unexpected finding in this study. Among othermotivational factors, signaling is used differently by all the four services. We also found supportfor Kaufmann’s et al. motivation model, and finally confirmed findings from previous studies.

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