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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.
131

On the use of smartphones as novel photogrammetric water gauging instruments: Developing tools for crowdsourcing water levels

Elias, Melanie 15 June 2021 (has links)
The term global climate change is omnipresent since the beginning of the last decade. Changes in the global climate are associated with an increase in heavy rainfalls that can cause nearly unpredictable flash floods. Consequently, spatio-temporally high-resolution monitoring of rivers becomes increasingly important. Water gauging stations continuously and precisely measure water levels. However, they are rather expensive in purchase and maintenance and are preferably installed at water bodies relevant for water management. Small-scale catchments remain often ungauged. In order to increase the data density of hydrometric monitoring networks and thus to improve the prediction quality of flood events, new, flexible and cost-effective water level measurement technologies are required. They should be oriented towards the accuracy requirements of conventional measurement systems and facilitate the observation of water levels at virtually any time, even at the smallest rivers. A possible solution is the development of a photogrammetric smartphone application (app) for crowdsourcing water levels, which merely requires voluntary users to take pictures of a river section to determine the water level. Today’s smartphones integrate high-resolution cameras, a variety of sensors, powerful processors, and mass storage. However, they are designed for the mass market and use low-cost hardware that cannot comply with the quality of geodetic measurement technology. In order to investigate the potential for mobile measurement applications, research was conducted on the smartphone as a photogrammetric measurement instrument as part of the doctoral project. The studies deal with the geometric stability of smartphone cameras regarding device-internal temperature changes and with the accuracy potential of rotation parameters measured with smartphone sensors. The results show a high, temperature-related variability of the interior orientation parameters, which is why the calibration of the camera should be carried out during the immediate measurement. The results of the sensor investigations show considerable inaccuracies when measuring rotation parameters, especially the compass angle (errors up to 90° were observed). The same applies to position parameters measured by global navigation satellite system (GNSS) receivers built into smartphones. According to the literature, positional accuracies of about 5 m are possible in best conditions. Otherwise, errors of several 10 m are to be expected. As a result, direct georeferencing of image measurements using current smartphone technology should be discouraged. In consideration of the results, the water gauging app Open Water Levels (OWL) was developed, whose methodological development and implementation constituted the core of the thesis project. OWL enables the flexible measurement of water levels via crowdsourcing without requiring additional equipment or being limited to specific river sections. Data acquisition and processing take place directly in the field, so that the water level information is immediately available. In practice, the user captures a short time-lapse sequence of a river bank with OWL, which is used to calculate a spatio-temporal texture that enables the detection of the water line. In order to translate the image measurement into 3D object space, a synthetic, photo-realistic image of the situation is created from existing 3D data of the river section to be investigated. Necessary approximations of the image orientation parameters are measured by smartphone sensors and GNSS. The assignment of camera image and synthetic image allows for the determination of the interior and exterior orientation parameters by means of space resection and finally the transfer of the image-measured 2D water line into the 3D object space to derive the prevalent water level in the reference system of the 3D data. In comparison with conventionally measured water levels, OWL reveals an accuracy potential of 2 cm on average, provided that synthetic image and camera image exhibit consistent image contents and that the water line can be reliably detected. In the present dissertation, related geometric and radiometric problems are comprehensively discussed. Furthermore, possible solutions, based on advancing developments in smartphone technology and image processing as well as the increasing availability of 3D reference data, are presented in the synthesis of the work. The app Open Water Levels, which is currently available as a beta version and has been tested on selected devices, provides a basis, which, with continuous further development, aims to achieve a final release for crowdsourcing water levels towards the establishment of new and the expansion of existing monitoring networks. / Der Begriff des globalen Klimawandels ist seit Beginn des letzten Jahrzehnts allgegenwärtig. Die Veränderung des Weltklimas ist mit einer Zunahme von Starkregenereignissen verbunden, die nahezu unvorhersehbare Sturzfluten verursachen können. Folglich gewinnt die raumzeitlich hochaufgelöste Überwachung von Fließgewässern zunehmend an Bedeutung. Pegelmessstationen erfassen kontinuierlich und präzise Wasserstände, sind jedoch in Anschaffung und Wartung sehr teuer und werden vorzugsweise an wasserwirtschaftlich-relevanten Gewässern installiert. Kleinere Gewässer bleiben häufig unbeobachtet. Um die Datendichte hydrometrischer Messnetze zu erhöhen und somit die Vorhersagequalität von Hochwasserereignissen zu verbessern, sind neue, kostengünstige und flexibel einsetzbare Wasserstandsmesstechnologien erforderlich. Diese sollten sich an den Genauigkeitsanforderungen konventioneller Messsysteme orientieren und die Beobachtung von Wasserständen zu praktisch jedem Zeitpunkt, selbst an den kleinsten Flüssen, ermöglichen. Ein Lösungsvorschlag ist die Entwicklung einer photogrammetrischen Smartphone-Anwendung (App) zum Crowdsourcing von Wasserständen mit welcher freiwillige Nutzer lediglich Bilder eines Flussabschnitts aufnehmen müssen, um daraus den Wasserstand zu bestimmen. Heutige Smartphones integrieren hochauflösende Kameras, eine Vielzahl von Sensoren, leistungsfähige Prozessoren und Massenspeicher. Sie sind jedoch für den Massenmarkt konzipiert und verwenden kostengünstige Hardware, die nicht der Qualität geodätischer Messtechnik entsprechen kann. Um das Einsatzpotential in mobilen Messanwendungen zu eruieren, sind Untersuchungen zum Smartphone als photogrammetrisches Messinstrument im Rahmen des Promotionsprojekts durchgeführt worden. Die Studien befassen sich mit der geometrischen Stabilität von Smartphone-Kameras bezüglich geräteinterner Temperaturänderungen und mit dem Genauigkeitspotential von mit Smartphone-Sensoren gemessenen Rotationsparametern. Die Ergebnisse zeigen eine starke, temperaturbedingte Variabilität der inneren Orientierungsparameter, weshalb die Kalibrierung der Kamera zum unmittelbaren Messzeitpunkt erfolgen sollte. Die Ergebnisse der Sensoruntersuchungen zeigen große Ungenauigkeiten bei der Messung der Rotationsparameter, insbesondere des Kompasswinkels (Fehler von bis zu 90° festgestellt). Selbiges gilt auch für Positionsparameter, gemessen durch in Smartphones eingebaute Empfänger für Signale globaler Navigationssatellitensysteme (GNSS). Wie aus der Literatur zu entnehmen ist, lassen sich unter besten Bedingungen Lagegenauigkeiten von etwa 5 m erreichen. Abseits davon sind Fehler von mehreren 10 m zu erwarten. Infolgedessen ist von einer direkten Georeferenzierung von Bildmessungen mittels aktueller Smartphone-Technologie abzusehen. Unter Berücksichtigung der gewonnenen Erkenntnisse wurde die Pegel-App Open Water Levels (OWL) entwickelt, deren methodische Entwicklung und Implementierung den Kern der Arbeit bildete. OWL ermöglicht die flexible Messung von Wasserständen via Crowdsourcing, ohne dabei zusätzliche Ausrüstung zu verlangen oder auf spezifische Flussabschnitte beschränkt zu sein. Datenaufnahme und Verarbeitung erfolgen direkt im Feld, so dass die Pegelinformationen sofort verfügbar sind. Praktisch nimmt der Anwender mit OWL eine kurze Zeitraffersequenz eines Flussufers auf, die zur Berechnung einer Raum-Zeit-Textur dient und die Erkennung der Wasserlinie ermöglicht. Zur Übersetzung der Bildmessung in den 3D-Objektraum wird aus vorhandenen 3D-Daten des zu untersuchenden Flussabschnittes ein synthetisches, photorealistisches Abbild der Aufnahmesituation erstellt. Erforderliche Näherungen der Bildorientierungsparameter werden von Smartphone-Sensoren und GNSS gemessen. Die Zuordnung von Kamerabild und synthetischem Bild erlaubt die Bestimmung der inneren und äußeren Orientierungsparameter mittels räumlichen Rückwärtsschnitt. Nach Rekonstruktion der Aufnahmesituation lässt sich die im Bild gemessene 2D-Wasserlinie in den 3D-Objektraum projizieren und der vorherrschende Wasserstand im Referenzsystem der 3D-Daten ableiten. Im Soll-Ist-Vergleich mit konventionell gemessenen Pegeldaten zeigt OWL ein erreichbares Genauigkeitspotential von durchschnittlich 2 cm, insofern synthetisches und reales Kamerabild einen möglichst konsistenten Bildinhalt aufweisen und die Wasserlinie zuverlässig detektiert werden kann. In der vorliegenden Dissertation werden damit verbundene geometrische und radiometrische Probleme ausführlich diskutiert sowie Lösungsansätze, auf der Basis fortschreitender Entwicklungen von Smartphone-Technologie und Bildverarbeitung sowie der zunehmenden Verfügbarkeit von 3D-Referenzdaten, in der Synthese der Arbeit vorgestellt. Mit der gegenwärtig als Betaversion vorliegenden und auf ausgewählten Geräten getesteten App Open Water Levels wurde eine Basis geschaffen, die mit kontinuierlicher Weiterentwicklung eine finale Freigabe für das Crowdsourcing von Wasserständen und damit den Aufbau neuer und die Erweiterung bestehender Monitoring-Netzwerke anstrebt.
132

Crowdshipping: Attesterande avhinder och möjligheter : Hur konceptet uppfattas av studenter i Sverige / Crowdshipping: Certification of obstacles and opportunities : How the concept is perceived by students in sweden

Vancea, Edward, Novljakovic, Harris January 2022 (has links)
E-handel har de senaste åren ständigt ökat vilket har bidragit till ökande krav på hållbaratransporter vilket medverkat till forskning av alternativ till traditionella transportföretag.Crowdshipping är ett koncept där det med hjälp av teknologiska applikationer kan utnyttjaindividers resurser för att skapa transportnätverk inom urbana områden. Användandet avindivider som redan är på väg till en plats och tar med ett paket i farten kan innebära mindrefordon på vägarna. I denna studie samlade vi in empirisk data genom att skicka ut en enkät till olika facebook-grupper bestående av studenter i Sverige och utförde två fokusgrupper med totalt åtta deltagare. Syftet med enkäten och fokusgrupperna var att undersöka respondenternasinställning och uppfattade hinder/möjligheter till crowdshipping. Med kunskap samlat utifrånvetenskapliga artiklar kunde ett teoretiskt ramverk etableras. Genom att studerat väsentligafaktorer till crowdshipping (tillit och säkerhet, miljö och hållbarhet, tid ochkompensation/prissättning) kunde vi analysera vårt empiriska material. Analysen byggs uppefter de teoretiska faktorerna som har inverkan på crowdshipping. Det visade sig attrespondenterna hade bekymmer med flertal säkerhetsaspekter inom CS-initiativ sompåverkade deras inställning negativt. Dock ansåg många respondenter initiativet som positivtifall det gick att säkerställa miljömässiga fördelar och flertalet säkerhetsaspektertillhandahölls. / E-commerce has steadily increased in recent years, which has contributed to increaseddemands for sustainable transport, which contributes to research into alternatives totraditional transport companies. Crowdshipping is a concept where, with the help oftechnological applications, it can utilize individuals' resources to create transport networks inurban areas. The use of individuals who are already on their way to a place and taking apackage on the go can mean fewer vehicles on the roads. In this study, we collected empirical data by sending out a questionnaire to various Facebookgroups consisting of students in Sweden and conducted two focus groups with a total of eightparticipants. The purpose of the survey and focus groups was to examine the respondents'attitudes and perceived obstacles/opportunities for crowdshipping. With knowledge gatheredbased on scientific articles, a theoretical framework could be established. By studyingsignificant factors for crowdshipping (trust and security, environment and sustainability, timeand compensation/pricing), we were able to analyze our empirical material. The analysis isbased on the theoretical factors that have an impact on crowdshipping. It turned out that therespondents had concerns with several security aspects within CS initiatives that had anegative effect on their attitude. However, many respondents considered the initiative to bepositive if it was possible to ensure environmental benefits and most safety aspects wereprovided.
133

Tasks and characteristics of end users during the open innovation processes on the social web

Plum, Alexander B. January 2012 (has links)
The present thesis aims to deduce tasks and characteristics of end users during the open innovation process on the social web. The social web with its communities, forums and blogs affords new prospects as well as unknown challenges for companies, and at the same has increasingly influenced academic research during the last few years. Especially research regarding communication behaviour on the social web as well as social web technologies has currently progressed well. However, in innovation research, social web technologies are currently primarily used to integrate users into the company’s innovation process, for example through company user toolkits or company innovation communities. In those cases users were excluded from their normal social web environment and integrated into a company’s environment, a sort of laboratory environment. Despite this, the present research project will use the natural behaviour, comments and discussions of users within their social web environment to develop and apply a new mixed-method approach with the aim to deduce tasks and characteristics of innovative end users on the social web. To apply the mixed-method approach within a longitudinal case study and to deduce statements and regularities regarding the innovation process on the social web, it was possible to analyse the end user developer online forum of one of the leading open source CRM software technologies. Based on this analysis, the assumptions from an extensive literature analysis could be verified and extended: it could be shown that the expected single innovative user does not exist. In fact, the process from the initial idea to an innovation requires different users with different characteristics and different points of view. They will be deduced, explained and presented within the present thesis.
134

The dynamics of innovation contests using firm-hosted communities

Langner, Benedikt Fabian January 2013 (has links)
Firms pursuing an open innovation strategy have increasingly turned to individuals as sources of new ideas. Two main approaches are often highlighted. First, firms can use online innovation contests, where individuals submit ideas in competition for a prize. Second, firms can use firm-hosted online communities, drawing from collaborative efforts of individuals with more intrinsic motivations to participate. A central challenge in both cases is that firms often struggle to sustain participation and effort of participants on an on-going basis. A third hybrid approach, where firms establish community-based innovation contests, has been largely ignored by research, but seems to help firms to engage participants on an on-going basis. This study focuses on community-based innovation contests to understand how firms engage communities to participate in contest over time. I conducted fieldwork at two firms that have successfully run them for many years, Chicago-based T-Shirt firm Threadless and Phoenix-based automotive firm Local Motors. Over ninety interviews with firm employees and community members, over six months of on-site observation at the two firms’ headquarters as well as internal documents and blog data have been collected and analysed. Based on this data the core of the thesis consists of three empirical chapters that examine how firms are able to engage the communities to participate in their contests on a regular basis. First, it shows that the addition of a community to contests increases contestants’ opportunities to learn. In experiential learning, contests provide experience whereas the community provides room for reflection and learning. These learning opportunities motivate contestants to come back and create contest entries on an on-going basis. Secondly, taking a social identity perspective, the research shows how the firms are able to engage the community members continuously by creating a joint firm-community identity. Lastly, it explains how these firms are able to influence community members’ perception of the tasks they are doing through the contest design. Firms are able to turn activities that have been traditionally regarded as work into a recreational activity.
135

The viability of crowdsourcing : a supply side market survey

Strauss, D Niel 03 1900 (has links)
Thesis (MBA)--Stellenbosch University, 2011. / Crowdsourcing is a new phenomenon, giving companies the ability to tap into the wisdom of crowds in order to solve complex problems, often at a fraction of the cost. In this document, the viability of crowdsourcing from the supply side is investigated with a market research questionnaire at the core of the research. Firstly, an overview of the current online crowdsourcing landscape is given with a focus on the big players, followed by a literature study on the motivation of solvers and their associated compensation needs. Because of the nature of crowdsourcing, an assumption is made that knowledge workers will be the biggest contributors in the form of solvers; this presumption is demonstrated by analysing responses to the questionnaire. The following research question is answered: What are the needs and profile of the solvers (supply side) of an internet platform that uses the principle of crowdsourcing to solve complex problems? It also answers the questions of many online crowdsourcing enthusiasts with regards to the typical solver and what their needs are, specifically with regards to compensation structures on these platforms. The typical solver profile was found to be predominantly male between the ages of 19 and 37, with a tertiary education or busy earning a degree of some sort and a strong will to become wealthy through applying this knowledge. These typical solvers have a primary objective to earn money with 100 per cent of the incentive paid to one „winner‟. They will participate more than three times even if they do not „win‟ the challenge and expect to earn more that R1 000 but less than R10 000 per day for this type of work. Certain limitations of the study are also addressed, like the clear self-selection bias and difficulty to generalise the findings to a well-defined group of people, as became evident from analysing questionnaire findings.
136

Σχεδιασμός και υλοποίηση crowdsourcing διαδραστικής εκπαιδευτικής εφαρμογής με την χρήση του σημασιολογικού ιστού

Σκαπέτης, Ανδρέας 14 October 2013 (has links)
Τα τελευταία χρόνια γίνεται ολοένα όλο και πιο έντονη η επιθυμία, τόσο από εκπαιδευτικούς ή μαθητές, αλλά και από άτομα μεγαλύτερης ηλικίας που θέλουν να αναπτύξουν την γνώση τους σε κάποιο αντικείμενο, για την δημιουργία εκπαιδευτικών μηχανών (λογισμικών) που θα μπορούν να αντικαταστήσουν σε μεγάλο βαθμό τον ρόλο του εκπαιδευτικού. Η προστιθέμενη αξία ενός εκπαιδευτικού λογισμικού θα μπορούσε να είναι η εύκολη πρόσβαση σε μεγάλο όγκο πληροφοριών, η πιο συστηματική εκμάθηση, καθώς και η εξοικονόμηση χρόνου και εκπαιδευτικών πηγών (εννοώντας τους εκπαιδευτικούς ως φυσικά πρόσωπα). Το ζητούμενο δεν είναι απλά η δημιουργία ενός εκπαιδευτικού λογισμικού αλλά ενός "σωστά" δομημένου εκπαιδευτικού συστήματος. Αυτό σημαίνει ότι ο εκπαιδευόμενος θα μπορεί να αντλεί σωστά και μεθοδικά πληροφορία από αυτό, όπως ακριβώς θα έκανε αν είχε στην διάθεσή του έναν καταρτισμένο εκπαιδευτικό. Στην παρούσα λοιπόν εργασία, μέσα από ένας συνδυασμό νέων τεχνολογιών όπως είναι αυτή των οντολογιών και του σημασιολογικού ιστού καθώς επίσης και θεωριών συσχετιζόμενων με την εκπαίδευση, παρουσιάζονται τα βήματα για δημιουργία ενός διαδραστικού crowdsoursing εκπαιδευτικού συστήματος. Παρουσιάζεται ένα σύστημα που με απλά λόγια θα είναι σε θέση να εξυπηρετεί μαθητές και εκπαιδευτικούς αλλά και οποιονδήποτε άλλο ενδιαφερόμενο, να προσφέρει μεθοδική εκμάθηση, να συλλέγει πληροφορία από τους χρήστες του την οποία να επεξεργάζεται και να την διαθέτει σε αυτούς σε ξανά βελτιωμένη και εμπλουτισμένη. / -
137

Convert your enemy into a friend : Innovation strategies for collaboration between record companies and BitTorrent networks

Andersen, Axel, Hristov, Emil January 2009 (has links)
<p>Problem: Record companies are facing a downturn in sales of music. This is seen as consequence of the growth of distribution of music through Internet by file sharing networks such as BitTorrent networks. On one side there are record companies who feel threatened of the illegal file sharing, and on the other side file sharing BitTorrent networks has increased dramatically in number of users since they first approached. Some record companies have responded by taking hostile actions towards the BitTorrent networks and their users with lawsuits and penalties for illegal file sharing. Other record companies and artists have joined forces with BitTorrent networks and see them as an advantage. Purpose: The purpose of this paper is to explore and analyze if, and how record companies can collaborate with the BitTorrent networks. Method: A hermeneutic inductive approach is used, in combination with qualitative interviews with both record companies and BitTorrent networks. Conclusions: It is argued that record companies can find a way in communicating and cooperating with BitTorrent networks. Instead of adopting hostile approaches and trying to restrict the technologies adopted by end users, companies should open themselves up and accept the current changes initiated and developed by BitTorrent networks. Thus, it was concluded that companies have to concentrate around collaborating with BitTorrent networks rather than fiercely protecting old business models. By opening up to the users, record companies will adopt open innovations approach that is characterized by combining external and internal ideas, as well internal and external paths to market, thus obtaining future technological developments. As for the BitTorrent networks, by going from outlaw to crowdsourcing mode, the networks’ creative solutions can be further harnessed by record companies. Finally, strengthening relationships between customers and music artists can be considered as beneficial for both record companies and BitTorrent networks. Thus, giving opportunities for customers to win special items, tickets for concerts, watch sound check, eat dinner backstage with the group, take pictures, get autographs, watch the show from the side of the stage, etc. can lead to valuable relationship in a long run.</p>
138

Specifying and Operationalizing an Organizational Theory of Crowdsourcing

Prpic, John January 2017 (has links)
Introduction: Despite rapid developments across multiple areas of research and practice, an organizational-level theory of Crowdsourcing has yet to emerge. Objectives: Therefore, this thesis has two major objectives; 1) specify the boundaries, constructs, and relationships of an organizational-level theory of Crowdsourcing, and 2) begin the theoretical validation process by operationalizing the theory for new exploratory, explanatory, and conceptual research. Methods: In respect to the first objective, an organizational-level theory of Crowdsourcing is created through inductive processes based upon observations of the real-world, and the extant organizational literature. In respect to the second objective, a mixed-methods research design is implemented to present three separate studies that use the theoretical perspective as a lens to operationalize new exploratory, explanatory, and conceptual Crowdsourcing research. Results: The Crowd Capital perspective is introduced, and defines three new constructs for the Crowdsourcing research; Dispersed Knowledge, Crowd Capability, and Crowd Capital. Crowd Capital theory is shown to be a valid theoretical contribution in the management research by illustrating the perspective’s incremental originality and scientific utility. Conclusion: The thesis develops and validates an organizational-level theory explaining how and why organizations implement Crowdsourcing, and through the exploratory and explanatory operationalizations of the Crowd Capital perspective, this work contributes to the empirical knowledge-base in the Crowdsourcing research. Further, this thesis contributes methodologically by illustrating and implementing a mixed-methods research design for theory validation in the Crowdsourcing research, while also supplying managers and executives with detailed guidance on the trade-offs inherent to the different modalities of Crowdsourcing. Thesis Organization: This thesis is organized in a monograph format comprised of eight chapters; 1) Introduction, 2) Literature review, 3) Theoretical model, 4) Methodology, 5) Exploratory research, 6) Explanatory research, 7) Conceptual research, and 8) Conclusion. As an outcome of this thesis, three journal articles and five conference proceedings have been accepted in peer-reviewed outlets1, and the author has been awarded a mini-track about Crowdsourcing at one of the most prestigious conferences in the field. The articles and the conference mini-track details are listed in Appendix A &amp; B at the end of the dissertation.
139

Beyond the Turk: Alternative platforms for crowdsourcing behavioral research

Peer, Eyal, Brandimarte, Laura, Samat, Sonam, Acquisti, Alessandro 05 1900 (has links)
The success of Amazon Mechanical Turk (MTurk) as an online research platform has come at a price: MTurk has suffered from slowing rates of population replenishment, and growing participant non-naivety. Recently, a number of alternative platforms have emerged, offering capabilities similar to MTurk but providing access to new and more naïve populations. After surveying several options, we empirically examined two such platforms, CrowdFlower (CF) and Prolific Academic (ProA). In two studies, we found that participants on both platforms were more naïve and less dishonest compared to MTurk participants. Across the three platforms, CF provided the best response rate, but CF participants failed more attention-check questions and did not reproduce known effects replicated on ProA and MTurk. Moreover, ProA participants produced data quality that was higher than CF's and comparable to MTurk's. ProA and CF participants were also much more diverse than participants from MTurk.
140

Weighted Networks: Applications from Power grid construction to crowd control

McAndrew, Thomas Charles 01 January 2017 (has links)
Since their discovery in the 1950's by Erdos and Renyi, network theory (the study of objects and their associations) has blossomed into a full-fledged branch of mathematics. Due to the network's flexibility, diverse scientific problems can be reformulated as networks and studied using a common set of tools. I define a network G = (V,E) composed of two parts: (i) the set of objects V, called nodes, and (ii) set of relationships (associations) E, called links, that connect objects in V. We can extend the classic network of nodes and links by describing the intensity of these associations with weights. More formally, weighted networks augment the classic network with a function f(e) from links to the real line, uncovering powerful ways to model real-world applications. This thesis studies new ways to construct robust micro powergrids, mine people's perceptions of causality on a social network, and proposes a new way to analyze crowdsourcing all in the context of the weighted network model. The current state of Earth's ecosystem and intensifying climate calls on scientists to find new ways to harvest clean affordable energy. A microgrid, or neighborhood-scale powergrid built using renewable energy sources attached to personal homes, suggest one way to ameliorate this energy crisis. We can study the stability (robustness) of such a small-scale system with weighted networks. A novel use of weighted networks and percolation theory guides the safe and efficient construction of power lines (links, E) connecting a small set of houses (nodes, V) to one another and weights each power line by the distance between houses. This new look at the robustness of microgrid structures calls into question the efficacy of the traditional utility. The next study uses the twitter social network to compare and contrast causal language from everyday conversation. Collecting a set of 1 million tweets, we find a set of words (unigrams), parts of speech, named entities, and sentiment signal the use of informal causal language. Breaking a problem difficult for a computer to solve into many parts and distributing these tasks to a group of humans to solve is called Crowdsourcing. My final project asks volunteers to 'reply' to questions asked of them and 'supply' novel questions for others to answer. I model this 'reply and supply' framework as a dynamic weighted network, proposing new theories about this network's behavior and how to steer it toward worthy goals. This thesis demonstrates novel uses of, enhances the current scientific literature on, and presents novel methodology for, weighted networks.

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