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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.
11

Cognitive offloading: O vlivu nových médií na kognitivní schopnosti člověka / Cognitive offloading: About the impact of new media on human cognitivity

Mikšovská, Markéta January 2020 (has links)
(in English) The subject of this master thesis is a cognitive offloading, sometimes also called cognitive outsourcing, meaning the impact of new media on human cognitive abilities. This work describes the evolution of the theoretical concept of cognitive offloading, types of cognitive offloading and it's functioning in today's society. Following Daniel Wegner's work, it describes basic concepts such as group mind and transactive memory and it focuses on a specific area of cognitive offloading - the impact of mobile photography on human memory. The thesis summarizes results of existing studies in this field and presents the results of a replicated pilot study conducted with the students of Czech high school. The aim of this study was to find out if - and to what extent - does smartphones impact one's memory and cognitive abilities in daily life. The conclusion analyzes the limits of this work and outlines further research possibilities in this field.
12

Altered proteins in the aging brain

Elobeid, Adila January 2016 (has links)
The classification of neurodegenerative disorders is based on the major component of the protein aggregates in the brain. The most common altered proteins associated with neurodegeneration are Hyperphosphorylated tau (HPt), beta amyloid (Aβ), alpha-synclein (αS) and transactive response DNA binding protein 43 (TDP43). In this study we assessed the incidence and the neuroanatomical distribution of proteins associated with neurodegeneration in the brain tissue of cognitively unimpaired subjects. We demonstrated the early involvement of the Locus Coeruleus (LC) with HPt pathology in cognitively unimpaired mid aged subjects, a finding which supports the notion that LC is an initiation site of HPt pathology. This may suggest that development of clinical assessment techniques and radiological investigations reflecting early LC alterations may help in identifying subjects with early stages of neurodegeneration. Furthermore, we studied a large cohort of cognitively unimpaired subjects with age at death ≥50 years and we applied the National Institute on Aging –Alzheimer’s disease (AD) Association (NIA-AA) guidelines for the assessment of AD related neuropathological changes. Interestingly, a considerable percentage of the subjects were classified as having an intermediate level of AD pathology. We also showed that the altered proteins;  HPt , Aβ, αS, and TDP43 are frequently seen in the brain of cognitively unimpaired subjects with age at death ≥50 years, the incidence of these proteins increased significantly with age. This finding suggests that neurodegeneration has to be extensive to cause functional disturbance and clinical symptoms. Moreover, we investigated the correlation between AD related pathology in cortical biopsies, the AD / cerebrospinal fluid (CSF) biomarkers and the Mini Mental State examination (MMSE) scores in a cohort of idiopathic Normal Pressure Hydrocephalus (iNPH) patients. We demonstrated that AD/ CSF biomarkers and MMSE scores reflect AD pathology in the cortical biopsies obtained from iNPH patients.  In conclusion, this study shows that the altered proteins associated with neurodegeneration are frequently seen in the brain tissue of cognitively unimpaired aged subjects. This fact should be considered while developing diagnostic biomarkers for identification of subjects at early stages of the disease, in order to introduce therapeutic intervention prior to the occurrence of significant cognitive impairment.
13

Collaborative information technology moderation in dynamic teamwork with team member departure

Keskin, Tayfun 20 October 2010 (has links)
The objective of this dissertation study is to provide the theoretical foundation for collaborative information technology moderation on team performance and give empirical evidence to support this relationship. The model provided in this study is supported by analytical proofs for the proposed hypotheses to define relationships among constructs in this research including departure (reduction in the number of team members), collaborative information technology functionality, transactive memory strength, and team performance. This research offers a theory that utilizes transactive memory systems (TMS) to examine the departure problem. The main research question is: Can collaborative information technologies (CIT) alleviate negative effects of departure? The theory in this study is structured around the indicators of TMS: specialization, coordination, and credibility. Findings showed that CIT functionality level plays a role in enhancing the group performance. This role is not direct but instead, is a moderation effect that alleviates the negative departure impact. In absence of departure, CIT impact can be confusing as it can be either positive or negative. My analytical results explain why information systems literature has had conflicting arguments on the role of technology. I propose that particular dynamic events and incidents, such as employee departure, help us understand the impact of CIT more clearly. Moreover, I employ transactive memory theory to explain how individuals develop and exchange knowledge in a group and how skills and knowledge can be lost due to departure. I also explain why and how team performance benefits from CIT when departure occurs. / text
14

Market Design for the Future Electricity Grid: Modeling Tools and Investment Case Studies

Tee, Chin Yen 01 April 2017 (has links)
The future electricity grid is likely to be increasingly complex and uncertain due to the introduction of new technologies in the grid, the increased use of control and communication infrastructure, and the uncertain political climate. In recent years, the transactive energy market framework has emerged as the key framework for future electricity market design in the electricity grid. However, most of the work done in this area has focused on developing retail level transactive energy markets. There seems to be an underlying assumption that wholesale electricity markets are ready to support any retail market design. In this dissertation, we focus on designing wholesale electricity markets that can better support transactive retail market. On the highest level, this dissertation contributes towards developing tools and models for future electricity market designs. A particular focus is placed on the relationship between wholesale markets and investment planning. Part I of this dissertation uses relatively simple models and case studies to evaluate key impediments to flexible transmission operation. In doing so, we identify several potential areas of concern in wholesale market designs: 1. There is a lack of consideration of demand flexibility both in the long-run and in the short-run 2. There is a disconnect between operational practices and investment planning 3. There is a need to rethink forward markets to better manage resource adequacy under long-term uncertainties 4. There is a need for more robust modeling tools for wholesale market design In Part II and Part III of this dissertation, we make use of mathematical decomposition and agent-based simulations to tackle these concerns. Part II of this dissertation uses Benders Decomposition and Lagrangian Decomposition to spatially and temporally decompose a power system and operation problem with active participation of flexible loads. In doing so, we are able to not only improve the computational efficiency of the problem, but also gain various insights on market structure and pricing. In particular, the decomposition suggests the need for a coordinated investment market and forward energy market to bridge the disconnect between operational practices and investment planning. Part III of this dissertation combines agent-based modeling with state-machine based modeling to test various spot, forward, and investment market designs, including the coordinated investment market and forward energy market proposed in Part II of this dissertation. In addition, we test a forward energy market design where 75% of load is required to be purchased in a 2-year-ahead forward market and various transmission cost recovery strategies. We demonstrate how the different market designs result in different investment decisions, winners, and losers. The market insights lead to further policy recommendations and open questions. Overall, this dissertation takes initial steps towards demonstrating how mathematical decomposition and agent-based simulations can be used as part of a larger market design toolbox to gain insights into different market designs and rules for the future electricity grid. In addition, this dissertation identifies market design ideas for further studies, particularly in the design of forward markets and investment cost recovery mechanisms.
15

The Influence of Communication Networks and Turnover on Transactive Memory Systems and Team Performance

Kush, Jonathan 01 May 2016 (has links)
In this dissertation, I investigate predictors and consequences of transactive memory system (TMS) development. A transactive memory system is a shared system for encoding, storing, and recalling who knows what within a group. Groups with well-developed transactive memory systems typically perform better than groups lacking such memory systems. I study how communication enhances the development of TMS and how turnover disrupts both TMS and its relationship to group performance. More specifically, I examine how communication networks affect the amount of communication, how the structure of the communication network affects the extent to which the group members share a strong identity as a group, and how both of these factors affect a group’s TMS. I also analyze how turnover disrupts the relationship between transactive memory systems and group performance. In addition, I examine how the communication network and turnover interact to affect group performance. I analyze these effects in three laboratory studies. The controlled setting of the experimental laboratory permits me to make causal inferences about the relationship of turnover and the communication network to group outcomes. Results promise to advance theory about transactive memory systems and communication networks.
16

Transactive Discourse during Assessment Conversations on Science Learning

Russell III, Homer Arthur 12 May 2005 (has links)
Transactive Discourse During Assessment Conversations on Science Learning by Homer A. Russell III It has been argued that development of science knowledge is the result of social interaction and adoption of shared understandings between teachers and students. A part of understanding that process is determining how student reasoning develops in groups. Transactive discussion is a form of negotiation between group members as they interpret the meaning of their logical statements about a topic. More importantly, it is a form of discourse that often leads to cognitive change as a result of the interaction between group participants as they wrestle with their different perspectives in order to achieve a common understanding. The research reported here was a correlational study designed to investigate the relationship between the various forms of transactive discussion and learning outcome performance seen in an investigation involving 24 students in a middle-SES high school located in southwest Atlanta, Georgia. Pretest and posttest measures of genetics reasoning, as well as curriculum content test data, were used in this study. Group discussion was captured on videotape and analyzed to determine whether transactional discussion was present and whether or not it had an effect on learning outcome measures. Results of this study showed that participant use of transactive discussion played a role in development of reasoning abilities in the area of genetics. It is suggested that teachers should monitor classroom discourse for the presence of transactive discussion as such discourse plays a role in fostering performance outcomes.
17

Applications of Agent-Based Modeling and Simulation in Organization Management / 組織管理におけるエージェント・ベース・モデル・シミュレーションの応用

WU, JIUN YAN 23 September 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(経済学) / 甲第22717号 / 経博第620号 / 新制||経||294(附属図書館) / 京都大学大学院経済学研究科経済学専攻 / (主査)教授 関口 倫紀, 教授 若林 直樹, 教授 椙山 泰生 / 学位規則第4条第1項該当 / Doctor of Economics / Kyoto University / DGAM
18

Self-organizing Coordination of Multi-Agent Microgrid Networks

January 2019 (has links)
abstract: This work introduces self-organizing techniques to reduce the complexity and burden of coordinating distributed energy resources (DERs) and microgrids that are rapidly increasing in scale globally. Technical and financial evaluations completed for power customers and for utilities identify how disruptions are occurring in conventional energy business models. Analyses completed for Chicago, Seattle, and Phoenix demonstrate site-specific and generalizable findings. Results indicate that net metering had a significant effect on the optimal amount of solar photovoltaics (PV) for households to install and how utilities could recover lost revenue through increasing energy rates or monthly fees. System-wide ramp rate requirements also increased as solar PV penetration increased. These issues are resolved using a generalizable, scalable transactive energy framework for microgrids to enable coordination and automation of DERs and microgrids to ensure cost effective use of energy for all stakeholders. This technique is demonstrated on a 3-node and 9-node network of microgrid nodes with various amounts of load, solar, and storage. Results found that enabling trading could achieve cost savings for all individual nodes and for the network up to 5.4%. Trading behaviors are expressed using an exponential valuation curve that quantifies the reputation of trading partners using historical interactions between nodes for compatibility, familiarity, and acceptance of trades. The same 9-node network configuration is used with varying levels of connectivity, resulting in up to 71% cost savings for individual nodes and up to 13% cost savings for the network as a whole. The effect of a trading fee is also explored to understand how electricity utilities may gain revenue from electricity traded directly between customers. If a utility imposed a trading fee to recoup lost revenue then trading is financially infeasible for agents, but could be feasible if only trying to recoup cost of distribution charges. These scientific findings conclude with a brief discussion of physical deployment opportunities. / Dissertation/Thesis / Doctoral Dissertation Systems Engineering 2019
19

Does my smartphone remember everything I need to remember? : A quantitative study on distributed cognition and how memory is affected by technical artifacts.

Gustafsson, Linn January 2023 (has links)
Technical artifacts, such as smartphones, computers, search engines and computer programs are extensively used by the modern human. It seems like people use these artifacts to remember important information and become better at finding information effectively with them as a constant available aid. This study aims to explore the possibility that human memory sieves away information that is saved in a database and instead focuses on remembering how to get access to the needed information. More precisely this paper aims to examine if people do focus on the content of information or where information is to be found. The motivation of the study was to investigate if smartphones can bring positive outcomes to human cognitive processes and if modern humans are adapting to the technical world. The present study is a replication of Sparrow et al.’s (2011) original study, which presents findings that suggest that humans remember things they know they have access to less than information they do not have access to. Two research questions were investigated in the present study through an experiment, conducted with university students at Linköping University as test participants. The experiment investigated if the participants focused on remembering the content of presented statements, or remembering if the statements were about to be saved or deleted after being exposed to them. The result presented nostatistically significance. Conclusively it is recommended to continue with further studies on the subject and to conduct more replication of Sparrow et al.’s original study, due to the conflicting findings. A speculation is that a cause for the lacking significant result is the relatively small sample size, and future studies are therefore recommended to test a greater number of test participants. Despite the result it is possible that humans use technical artefacts to enhance cognitive processes, and use smartphones as a transactive memory partners, due to the extensive use of technical artifacts and the original study’s findings.
20

Generation and the Google Effect: Transactive Memory System Preference Across Age

Siler, Jessica 01 August 2013 (has links)
A transactive memory system (TMS) is a means by which people may store information externally; in such a system the task of remembering is offloaded by remembering where information is located, rather than remembering the information itself. As Sparrow et al. (2011) suggest in the article Google Effects on Memory: Cognitive Consequences of Having Information at Our Fingertips, people are beginning to use the internet and computers as a TMS, and this use is changing the way people encounter and treat information. The purpose of this thesis is to investigate whether preference for TMS type (either with books or with computers) varies across age groups. An interaction between TMS preference and age was hypothesized. Before the onset of the internet age, information was primarily found in books and other print materials whereas now the internet is more frequently used, thus this shift in thinking and habit across generations was expected to emerge in the data. The study yielded a total of 51 participants, 32 from the young age group (ages 18-24) and 19 from the old (ages 61-81). A modified Stroop task and question blocks (for priming purposes) were employed to examine whether people are prone to think of book- or computer-related sources when in search of information. Also, a "Look up or Learn" tendencies survey was used to better understand how people decide whether certain information should be learned or left to be "looked up" later (Yacci & Rosanski, 2012). The mixed ANOVA did not reveal main effects for question difficulty or TMS type, nor was an interaction with age found. The results were not consistent with those of Sparrow et al. (2011) and did not show significance for TMS preference. Future studies should continue to examine the Google effect and TMS preference, as it bears important applications for a number of fields.

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