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Wong, King-yu Natalie. "The effect of contextual cues on the perceptual normalization of Cantonese level tones." Click to view the E-thesis via HKUTO, 2001. http://sunzi.lib.hku.hk/hkuto/record/B36208097.
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Thesis (B.Sc)--University of Hong Kong, 2001.<br>"A dissertation submitted in partial fulfilment of the requirements for the Bachelor of Science (Speech and Hearing Sciences), The University of Hong Kong, May 4, 2001." Also available in print.
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Lenz, Lauren Holt. "Statistical Methods to Account for Gene-Level Covariates in Normalization of High-Dimensional Read-Count Data." DigitalCommons@USU, 2018. https://digitalcommons.usu.edu/etd/7392.
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The goal of genetic-based cancer research is often to identify which genes behave differently in cancerous and healthy tissue. This difference in behavior, referred to as differential expression, may lead researchers to more targeted preventative care and treatment. One way to measure the expression of genes is though a process called RNA-Seq, that takes physical tissue samples and maps gene products and fragments in the sample back to the gene that created it, resulting in a large read-count matrix with genes in the rows and a column for each sample. The read-counts for tumor and normal samples are then compared in a process called differential expression analysis. However, normalization of these read-counts is a necessary pre-processing step, in order to account for differences in the read-count values due to non-expression related variables. It is common in recent RNA-Seq normalization methods to also account for gene-level covariates, namely gene length in base pairs and GC-content, the proportion of bases in the gene that are Guanine and Cytosine.
Here a colorectal cancer RNA-Seq read-count data set comprised of 30,220 genes and 378 samples is examined. Two of the normalization methods that account for gene length and GC-content, CQN and EDASeq, are extended to account for protein coding status as a third gene-level covariate. The binary nature of protein coding status results in unique computation issues. The results of using the normalized read counts from CQN, EDASeq, and four new normalization methods are used for differential expression analysis via the nonparametric Wilcoxon Rank-Sum Test as well as the lme4 pipeline that produces per-gene models based on a negative binomial distribution. The resulting differential expression results are compared for two genes of interest in colorectal cancer, APC and CTNNB1, both of the WNT signaling pathway.
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Meneray, Jennifer. "Coming Out| When Micro Level Vulnerabilities lead to Macro Level Risk." Thesis, The George Washington University, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10822934.
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<p> Exploratory projects have the capability to emerge new ways of understanding data. Non-traditional perspectives, like the intersectional-vulnerability standpoint used in this project, enable researchers to step back and look at experiences differently. At the beginning of this paper, I relate my experience of coming out as lesbian to the experience of coming out as a child witness of abuse in order to set the standard of how I conceptualize coming out. Coming out was an experience that connects LGBTQ people across the spectrum allowing me to use that experience to bring LGBTQ identities together. Assumptions about the coming out experience in relation to sexual orientation and gender identity are challenged and a new theory emerges. Related to coming out, the experience of getting out of an abusive relationship reflects parallel perceptions around fear, risk, and vulnerability. It is by building the bridge between researcher and participants that I was able to challenge bias and create a new idea about the coming out/getting out process for LGBTQ survivors. </p><p>
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Nordén, Johan. "Assessment of methods for microRNA isolation, microRNA amplification, and development of a normalization strategy for sepsis biomarker research." Thesis, Högskolan i Skövde, Institutionen för biovetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-18442.
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Sepsis, defined by organ dysfunction caused by an adverse immune response of the host to an infection, comes with considerable cost in human lives and as a substantial burden financially. Significant upgrades have been made over the past two decades when diagnosing and treating sepsis but still with room for improvements. Early detection is a cornerstone in the fight against sepsis, and the focus on strengthening diagnostics is in the forefront of modern research. The implementation of biomarkers may be the path of progression in this objective. This study aimed at establishing procedural foundations when using microRNAs as potential biomarkers. The study conducted looked at: (1) Isolation procedure, of microRNA from human plasma, of three kits: Total RNA Purification Kit (Norgen Biotech), miRNAeasy Serum/Plasma Kit (Qiagen), and miRNeasy Serum/Plasma Advanced Kit (Qiagen). (2) Amplification of miRNA through two Reverse Transcription Quantitative PCR methods: Two-tailed RT-qPCR (TATAA Biocenter), and miRCURY LNA miRNA PCR (Qiagen). (3) Developing a normalization strategy by identifying miRNA reference targets in a geNorm pilot experiment. Qubit analysis revealed that the two isolation kits from Qiagen performed similar, and better that the Norgen kit. The Two-tailed RT-qPCR failed to amplify miRNA samples, whereas the miRCURY LNA miRNA PCR showed consistent amplification across samples with a high call rate. The geNorm analysis concluded that hsa-miR-425-5p and hsa-miR-93-5p was the optimal reference target set. The study demonstrated that the isolation kits from Qiagen coupled with the miRCURY LNA miRNA PCR is a viable option for future miRNA biomarker studies.
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Kline, David. "Systematically Missing Subject-Level Data in Longitudinal Research Synthesis." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1440067809.
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Doucette, Wendy C. "Developing a Comprehensive Suite of Graduate-Level Research Support." Digital Commons @ East Tennessee State University, 2016. https://dc.etsu.edu/etsu-works/5365.
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Graduate students are the largest-growing group at East Tennessee State University. While it is easy to assume that graduates have mastered the basics of searching and conducting research, this assumption is largely unfounded. Whether they did learn these skills as undergraduates or not, graduates are rarely prepared for the project management challenge of undertaking the biggest research assignment of their lives. Graduate students often have additional stressors not faced by undergraduates: established careers, families, and greater financial responsibilities. Conceived during Summer 2015 and rolled out as an ongoing series in Fall 2015, the Graduate Student Workshops offered by the Sherrod Library provide instruction in the following areas: scholarly research, papers, and publishing; comprehensive project management; academic searching; APA style; citation management; and establishing a professional identity. As the program coordinator, the Graduate Services Librarian will discuss the origination of the program, from its inception in ETSU’s Graduate Thesis and Dissertation Boot Camp to its growth as a full-fledged series. Creating new relationships, leveraging partnerships with other faculty and departments, and organizing and marketing these services are critical to program success. Scheduling, logistics, costs, and assessment will also be discussed. After the program and discussion, attendees should be able to: recognize the significant function librarians can provide to graduate student research support convey the value of formal, targeted intervention to graduate students and campus administrators create offerings to support their own graduate students
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Vashishtha, Saurabh. "Stochastic modeling of eukaryotic transcription at the single nucleotide level." Thesis, Lethbridge, Alta. : University of Lethbridge, Dept. of Chemistry and Biochemistry, c2011, 2011. http://hdl.handle.net/10133/3190.
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DNA is the genetic material of a cell and is copied in the form of pre-mRNA through
transcription in eukaryotes. RNA polymerase II is responsible for the transcription of all
genes that express proteins. Transcription is a significant source of the stochasticity in
gene expression. In this thesis, I discuss the development of a biochemically detailed
model of eukaryotic transcription, which includes pre-initiation complex (PIC) assembly,
abortive initiation, promoter-proximal pausing and termination as the points that can be
slow steps for transcription. The stochastic properties of this model are studied in detail
by stochastic simulations with some preliminary mathematical analysis. The results of
this model suggest that PIC assembly can play the most significant role in affecting the
transcription dynamics. In addition, promoter-proximal pausing has been identified as a
potential noise regulatory step in eukaryotic transcription. These results show excellent
agreement with many experimental studies.<br>x, 107 leaves : ill. ; 29 cm
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Tsironas, Polymenis. "Reshaping Stockholm, A macro level research of spatial relations and networks through a micro level study." Thesis, KTH, Stadsbyggnad, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-127257.
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Savage, Shari L. "Lolita Myths and the Normalization of Eroticized Girls in Popular Visual Culture: The Object and the Researcher Talk Back." Columbus, Ohio : Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1242768387.
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Stevens, Madeleine M. "Research Identity Among Master’s-Level Counseling Students: Exploring Research Competencies, Motivation, and Advisory Working Alliance." Ohio University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1618505096365955.
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Stevens, Madeleine M. "Research Identity Among Master’s-Level Counseling Students: Exploring Research Competencies, Motivation, and Advisory Working Alliance." Ohio University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1618505096365955.
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Garay, Beñat. "High-level language design for IMMA-Virtual Driver DHM Research." Thesis, Högskolan i Skövde, Institutionen för ingenjörsvetenskap, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-11236.
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The growing implementation of ergonomics in the automotive sector sets high demands on Digital Human Modelling (DHM) functionalities towards the simulation of more realistic environments and the reduction of physical model dependency. During the current degree project a leading element that smartly assembles DHM usage (implementation of high-level commanding languages) was designed, revolving around the industries’ needs which were gathered and interpreted in order to organize current functions in this language and suggest new complementary functions that would create a language environment suitable for non-expert users. This was achieved by focusing in an intuitive word-function structure, the proposal of defaults and other tools that aid users with different kinds of expertise. The need for realism of simulations was assessed by the language design especially by designing means to coordinate synchronic manikin-actions.<br>Virtual Driver
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Buschkühl, Lisbeth. "Multi-level capacitated lotsizing with setup carryover /." Köln : Kölner Wiss.-Verl, 2008. http://d-nb.info/989792714/04.
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Ågren, Magnus. "High-level modelling and local search /." Uppsala : Univ. : Dept. of Information Technology, Univ, 2005. http://www.it.uu.se/research/publications/lic/2005-003/.
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Mokhtar, Basim. "Combined phototherapy/low level laser therapy : analgesic and neurophysiological effects." Thesis, University of Ulster, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.357573.
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Ross, Julie 1959. "Observation and characterization of low-level air temperatures above a subarctic snowpack." Thesis, McGill University, 1988. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=61681.
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Hayden, Colleen Marie. "Measuring leader-level engagement: Addressing the gap in employee engagement research." Wright State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=wright1575283306094234.
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Babington, Lynn Marie. "Assessing context of care at the unit level of the organization /." Thesis, Connect to this title online; UW restricted, 1995. http://hdl.handle.net/1773/7336.
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Aldous, Colleen Michelle. "University level genetics students' competencies in selected science process skills." Diss., Pretoria : [s.n.], 2005. http://upetd.up.ac.za/thesis/available/etd-02092006-120752.
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Colliander, Cristian. "Science mapping and research evaluation : a novel methodology for creating normalized citation indicators and estimating their stability." Doctoral thesis, Umeå universitet, Sociologiska institutionen, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-94189.
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The purpose of this thesis is to contribute to the methodology at the intersection of relational and evaluative bibliometrics. Experimental investigations are presented that address the question of how we can most successfully produce estimates of the subject similarity between documents. The results from these investigations are then explored in the context of citation-based research evaluations in an effort to enhance existing citation normalization methods that are used to enable comparisons of subject-disparate documents with respect to their relative impact or perceived utility. This thesis also suggests and explores an approach for revealing the uncertainty and stability (or lack thereof) coupled with different kinds of citation indicators.This suggestion is motivated by the specific nature of the bibliographic data and the data collection process utilized in citation-based evaluation studies. The results of these investigations suggest that similarity-detection methods that take a global view of the problem of identifying similar documents are more successful in solving the problem than conventional methods that are more local in scope. These results are important for all applications that require subject similarity estimates between documents. Here these insights are specifically adopted in an effort to create a novel citation normalization approach that – compared to current best practice – is more in tune with the idea of controlling for subject matter when thematically different documents are assessed with respect to impact or perceived utility. The normalization approach is flexible with respect to the size of the normalization baseline and enables a fuzzy partition of the scientific literature. It is shown that this approach is more successful than currently applied normalization approaches in reducing the variability in the observed citation distribution that stems from the variability in the articles’ addressed subject matter. In addition, the suggested approach can enhance the interpretability of normalized citation counts. Finally, the proposed method for assessing the stability of citation indicators stresses that small alterations that could be artifacts from the data collection and preparation steps can have a significant influence on the picture that is painted by the citationindicator. Therefore, providing stability intervals around derived indicators prevents unfounded conclusions that otherwise could have unwanted policy implications. Together, the new normalization approach and the method for assessing the stability of citation indicators have the potential to enable fairer bibliometric evaluative exercises and more cautious interpretations of citation indicators.
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Williams, Sarah Louise. "Promoting children's mental health at a whole-school level using action research." Thesis, University of Birmingham, 2013. http://etheses.bham.ac.uk//id/eprint/4712/.
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This study aimed to explore school staff’s, parents’ and children’s understanding of mental health and identify what risk and protective factors affect children’s mental health. The key aims were to gain information about how mainstream primary schools promote children’s mental health, and to explore children’s, parents’ and school staffs’ understanding of children’s mental health and factors which promote or demote development. All of the schools who responded to the questionnaire considered that mental health promotion should be carried out by specialist. The findings from this initial survey suggested that to achieve the active involvement of school staff, further support was required to enable school staff to feel competent, confident and knowledgeable in this field. The participants in the action research phase of this study identified a number of factors within the individual, the micro, exo- and the macro-systems which they believed affected children’s mental health. The integrated MacDonald and O’Hara Ten Element Map (1998) and Bronfenbrenner’s bioecological model (2005) which consider the individual to be at the centre of and embedded in a number of environmental systems, afforded effective frameworks for exploring the school community’s understanding of children’s mental health, for conceptualising the findings from a bioecological perspective, and for planning action steps through which to enhance the impact of schooling on children’s mental health.
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Lindahl, Rebecca. "Research-Based Characteristics of Professional Learning Communities at the High School Level." ScholarWorks, 2011. https://scholarworks.waldenu.edu/dissertations/859.
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An educational problem facing high schools in 2 Midwestern school districts is that few local contextual experiences exist for developing professional learning communities that contain research-based characteristics. Identifying such experiences is important to school leaders and teachers. The purpose of this study was to examine 2 local high school professional learning communities to identify research-based characteristics such as practice-based discussions and a focus on learning and results. Constructivism and social change theory provided the theoretical foundation. A single research question sought the presence of research-based characteristics. The characteristics formed the conceptual framework and emerged from many voices in the field. Qualitative case study research methods guided the study; each high school served as a case. Interviews with 10 educators, observations of 4 team meetings, and examination of artifacts from the sites were conducted to collect data. Data analysis included coding information from interviews, meetings, and artifacts; developing individual case narratives; and constructing a cross-case analysis. A key finding was that all research-based characteristics were present in each school. One conclusion reached was that strong administrative leadership contributed positively to the presence of characteristics. Another was that operating from a learning model (e.g., AIW [Authentic Intellectual Work] or DuFour) contributed positively as well. Several recommendations are included and focus on following a model under strong administrative leadership. Given the findings, positive implications for social change include more effective teaching, more authentic collaboration in schools, and a culture of teacher excellence.
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Berkowitz, Jack Philip. "Required force level and isometric tracking." Thesis, This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-11012008-063500/.
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Ball, Jamie L. "Bullying Prevention and Grade-Level Differences in Urban Elementary Schools." Thesis, Grand Canyon University, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10839783.
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<p> Bullying prevention in schools has arguably met with limited success in the United States. Diversity negatively impacts the success of bullying prevention programs. Furthermore, researchers do not agree upon intervention timing and appropriate grade-level to implement bullying prevention and social-emotional learning and skill-building programs. Urban schools faced with high poverty have an increased need for bullying prevention programs to alleviate bullying and aggression. The purpose of this study was to test for significant differences between urban elementary schools after a treatment group participated in a targeted bullying prevention and social skill-building program and to test for grade-level differences from fall to spring using a quantitative causal-comparative design. The sample included four urban schools in Ohio with 24 grade-levels and six time points each. The data generated were analyzed retrospectively in a causal-comparative research design. A two-way mixed ANOVA BBW was conducted on the summary totals of the number of students disciplined for bullying and aggression using six time points with three for fall or before treatment and three for spring or after treatment comparing a treatment group to a control group. Significant differences were not found between control and treatment or between grade groups (<i>p</i> > .05). Bullying and aggression started the school year and ended the school year slightly higher in the 4-6<sup>th</sup> grade group. Significant differences were found from fall to spring (<i>F</i> (5,16) = 7.704, <i>p</i> = .001). Overall the study findings indicate the targeted bullying prevention and social-skill building program did not result in reducing bullying and aggressive behavior in the sample population.</p><p>
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Gudmundsson, Kristinn. "Control of salinity intrusion caused by sea level rise." Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-11242009-020133/.
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Knoth, Kenneth Charles. "Biological Course-Based Undergraduate Research Experiences| An Examination of an Introductory Level Implementation." Thesis, Southern Illinois University at Edwardsville, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10616893.
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<p> Course-based undergraduate research experiences (CUREs) provide authentic research benefits to an entire laboratory course population. CURE experiences are proposed to enhance research skills, critical thinking, productivity, and retention in science. CURE curriculum developers face numerous obstacles, such as the logistics and time commitment involved in bringing a CURE to larger student populations. In addition, an ideal CURE topic requires affordable resources, lab techniques that can be quickly mastered, time for multiple iterations within one semester, and the opportunity to generate new data. This study identifies some of the CURE activities that lead to proposed participant outcomes. Introductory Biology I CURE lab students at Southern Illinois University Edwardsville completed research related to the process of converting storage lipids in microalgae into biodiesel. Data collected from CURE and traditional lab student participants indicate increased CURE student reports of project ownership, scientific self-efficacy, identification as a scientist, and sense of belonging to a science community. Study limitations and unanticipated benefits are discussed.</p><p>
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Hamilton, I. G. "Energy epidemiology : an epidemiological approach to empirically-based population-level energy demand research." Thesis, University College London (University of London), 2015. http://discovery.ucl.ac.uk/1469031/.
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The shift to a low carbon economy and the need to address energy demand priorities will involve the retrofit of millions of buildings resulting in changes in energy demand services at the national and international scale. Studying energy demand in buildings at a population level is different than in individual or small samples because of population heterogeneity. Evaluating policies and determining the effect of technologies in situ in millions of buildings means using techniques that support that level of analysis and use empirically derived data that can represent complex real-world conditions. Health epidemiology, which studies the distribution and determinants of population health outcomes, offers a compelling framework for studying population level energy demand. The aim of this thesis is to determine whether the adaption of the conceptual and methodological framework of epidemiology can support the study of energy, people and buildings. This thesis tests this hypothesis by examining relevant epidemiological concepts and its methodological framework along with three studies that adapt and apply epidemiological methods to energy demand and energy efficiency retrofits in UK houses. The method studies use a database of over 13 million dwellings to study energy efficiency retrofit uptake and their impact on energy demand. The method study findings support the case that an epidemiological approach to energy demand provides an appropriate and plausible conceptual and methodological framework for determining population-level evidence to inform modelling and policy development and evaluation. Adapting the epidemiological approach is not a panacea to dealing with the challenges facing the field of research in energy demand in buildings. However, it does provide a set of concepts, methods and analysis tools that are capable of supporting an empirically-based population-level research approach, identified as a necessary step towards to developing a robust foundation of evidence.
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Jui-ChenHsiao and 蕭瑞辰. "Multi-level focus species detection for Gene name Normalization." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/52318395192012007882.
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碩士<br>國立成功大學<br>醫學資訊研究所<br>100<br>Gene name normalization (GN) is the task of normalizing and mapping the gene mentions in the literature to the Entrez gene identifiers. One challenge in GN task, called “Species Disambiguation”, is how to assign the correct species identifiers to the gene mentions. This is important for GN task because the same gene names may belong to the different species and, their Entrez gene identifiers will be different. There is also another species ambiguous problem, which is the different species names may belong to the same taxonomy identifier. In this paper, we propose a multi-level focus species detection model to solve the species assignation problem. We predict the focus species of gene mentions using four different context levels, which the gene mentions locate to. We use the species cue words extracted from the articles in the corpus as our processing entities . The confidence of each entity is calculated by the proposed EFAISF model, which represents how important the entity is to the species. The final correct species identifier is decided by the Relation Guide Factor method which could detect the most probably answer to the gene mention. Our method not only performs well but also solves the problem which the sentence has no species mention or the article has no species mention. In DECA corpus, we outperform others species assignation methods and attain the precision rate of 88.22%.
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Hsueh, Hui-Fen, and 薛慧芬. "The Research of Normalization Methods for High Density Oligonucleotide Array." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/31107592972499927582.
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碩士<br>國立政治大學<br>統計研究所<br>93<br>High-density oligonucleotide array gene experiment is a new biological technology. More than thousands of gene data can be obtained in an array. The data processing includes background correction, normalization, probe specific background correction and summarizing the probe set value into one expression measure. The goal of normalization is to remove the systematic variation induced in the experiment while keeping the biological variation of interest. Using the purified data, one will obtain more accurate conclusions in subsequent statistical analysis. Firstly, we introduce the data processing procedures. Three normalization methods, which include Scaling, Cyclic Loess and Quantile, are explained in detail and illustrated by a real data set. Moreover, a simulation study is conducted to compare the three methods. Four quantities, Mean of IQR, Mean of Standard Deviation, Diff Statistics and Outlier, are proposed for assessment. Not only the performances of the three normalization methods but also the properties of the four proposed criteria are given and studied in this research.
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Jong-Jyh, Tash, and 蔡宗志. "Character Partition. Normalization and Recognition Research of License Plate Recognition System." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/15381096599400703564.
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碩士<br>國立交通大學<br>電機與控制工程系<br>87<br>On the increase of car, so how to use automatic license plate recognition system for car''s conservation is important. Although the history of license plate recognition system research is long, the system still has many faults. In our study, we develop a license plate recognition system whose hardware and software update conveniently.
The research of thesis focuses on Character Partition Horizontal Normalization and Recognition. The purpose of Horizontal Normalization is to cut the region that is out of the character horizontal edge. And let the horizontal of character are the same. After this process the character partition and recognition is simple. On the character partition research, we use two methods. One is using template map to partition the character of license plate. The other is using growing region method to partition the character. Both of those two methods have advantage and disadvantage. The result of our system is using growing region to partition the character of license plate. Because of this method has batter adaptability and correct percentage. Recognition is the last part in our process. Because of the size and shape of character is almost the same, so we use statistics to create the stander map character, and then recognition these character with map. But this method does not recognize the shape similar group like O. D. Q and 0. So we add shape and other particularity to redouble recognition.
In our study the testing samples include 362 pieces of license plate image those were come form realistic parking lot''s monitorial system, wherefore our experimental inference is dependable and our implement system is realizable.
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CHANG, PEI-CHE, and 張培哲. "Research on Signal - to - Noise Ratio Improvement of Normalization Fuzzy Logic Kalman Filter." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/p3k583.
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碩士<br>建國科技大學<br>自動化工程系暨機電光系統研究所<br>105<br>This paper is mainly to create a new filter, can really improve the signal to noise ratio algorithm. This filter will first normalize the signal, and then with the fuzzy logic of the center of gravity to demodulate the parameters of the Kalman filter, the input signal can be suppressed noise, and improve the improved signal to noise ratio. The design process of this paper is (1) using Gold Wave software to record the signal with parametric noise. (2) Use of fuzzy Kalman filter on the signal noise reduction, the signal clearer and further to the signal to noise ratio (Signal To Noise Ratio) improved. It is expected that the speed and accuracy of signal processing will be increased by increasing the signal-to-noise ratio. In the future, it can be widely used in 3C products and robot voice controllers, and it is believed that the noise suppression of the signals is very effective.
Keywords: Filter, Signal To Noise Ratio, Normalization, Fuzzy Logic, Kalman Filter, Gold Wave Software
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Dobbs, Angie. "Issues of Computational Efficiency and Model Approximation for Spatial Individual-Level Infectious Disease Models." Thesis, 2011. http://hdl.handle.net/10214/3248.
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Individual-level models (ILMs) are models that can use the spatial-temporal nature of disease data to capture the disease dynamics. Parameter estimation is usually done via Markov chain Monte Carlo (MCMC) methods, but correlation between model parameters negatively affects MCMC mixing. Introducing a normalization constant to alleviate the correlation results in MCMC convergence over fewer iterations, however this negatively effects computation time.
It is important that model fitting is done as efficiently as possible. An upper-truncated distance kernel is introduced to quicken the computation of the likelihood, but this causes a loss in goodness-of-fit.
The normalization constant and upper-truncated distance kernel are evaluated as components in various ILMs via a simulation study. The normalization constant is seen not to be worthwhile, as the effect of increased computation time is not outweighed by the reduced correlation. The upper-truncated distance kernel reduces computation time but worsens model fit as the truncation distance decreases.<br>Studies have been funded by OMAFRA & NSERC, with computing equipment provided by CSI.
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Wang, Yen-Chun, and 王彥鈞. "Business-Level Web Stores Adoption Behavior Research." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/28620196036267664728.
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碩士<br>建國科技大學<br>服務與科技管理研究所<br>103<br>In recent years, the development of e-commerce has affected people's shopping behavior. It also changed traditional business models. The online store platform do not need to writte programs so it can reduce user's entry barriers. It not only benefits for users to start their online business easier but also to expand their business territory. Therefore, this study aims to investigate the enterprise's intention of using e-commerce platform.
The Partial Least Square (PLS) analysis was used in this study. Those samples were collected physical store operators from August 5 to November 20 in 2014, involving 97 samples from Taiwan and 35 samples from China. This study consisted three parts which are evaluating total samples, comparing of running the online store or not and comparing of planning to run the online store or not in the future.
The conclusion of this study found that the first part Perceived Usefulness (PU) of electronic store will be affected by people's cognition. The second part Proportion that operators who don't have electronic store affected by social influence is higher than operators who have electronic store. The third part Personal Innovativeness (PI) will affect operators who have no plans to open an e-commerce store.
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曾秀珠. "Using sorting normalization and regression approach to build stock selection model:an empirical research on Taiwan stock market." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/70570486195271152443.
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Ho, Chang-Xian, and 何昌憲. "Research on Image Segmentation Using Level Set Methods." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/50087769656012493221.
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碩士<br>國立交通大學<br>資訊科學系所<br>93<br>In recent years, with the development of computer technology, digital image processing and its applications are more and more important. Image segmentation is an important and basic processing before other higher level applications. Image Segmentation has become one of the
major subjects in image processing. The purpose of this thesis is to explore the image segmentation using Level Set Methods. Level Set Methods are novel numerical methods, they express curves or surfaces easily and have the Convenient feature of dealing with PDE calculations. We
implement several basic and important methods of image segmentation using level set methods. Then discuss the main problems encountered in practice and their pros. and cons. on image segmentation.
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Shan-WenChen and 陳善文. "Analysis and Research of Multi-level Computing Architecture." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/9ex6ga.
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碩士<br>國立成功大學<br>電機工程學系<br>106<br>This thesis focuses on the research of parallel multi-core processor architecture. Firstly, it analyzes the Multi-Level Computing Architecture (MLCA) which is established by SystemVerilog, and deeply understands the execution behavior of the parallel control processor (CP) of the upper task level. After that, the lower processing unit (PU) and the peripheral memory are designed to implement the MLCA parallel multi-core architecture; the upper layer CP of the MLCA is responsible for analyzing and recording the dependencies between tasks during execution, and assigning the ready tasks to the parallel PUs. Execute and pass the execution result back to the CP record.
Three different experiments were performed for this system. The experiment was performed with a multi-level computing architecture MLCA multi-core architecture to perform different task programs, including inner product, fast Fourier transform and eight queen experiments. We analyzed three task tests. The execution behavior of the program and verify the correctness of the execution results of the processor unit in the MLCA.
Finally, summarize and analyze the three experiments separately, and then discuss them comprehensively because of the experience gained by these three experiments on our MLCA system.
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Riggs, Brandon S. "A Multi-Level, Cross-Level Examination of Leader and Team Member Outcomes of Leader-Leader Exchange Differentiation." Thesis, 2016. http://hdl.handle.net/1805/10989.
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Indiana University-Purdue University Indianapolis (IUPUI)<br>Scholars have repeatedly demonstrated the positive benefits of high-quality leader-member exchange (LMX) for employees and organizations alike. Although some research has examined outcomes of differentiation of LMX relationships within teams, there is scant research into the way in which the combination of LMX and LMX differentiation (LMX-D) interact at the leader-level in the workplace hierarchy and the trickle-down effects these leader relationships have on subordinates. Moreover, no research has examined the potential buffering effect that subordinate team LMX may have on leaders who are experiencing the desire to withdraw from the organization as a result of the combination of their leader-leader exchange (LLX) relationships and the LLX differentiation (LLX-D) they perceive on their own leader teams. Thus, the present study sought to combine LMX and multilevel leadership theories to examine the effects of these leader-level exchange relationships on turnover intentions (TOI) for both individuals in leader-member dyads. Results suggested stronger negative relationships between LLX and TOI for both leaders and members when LLX-D is lower. However, examining this relationship at the leader-level when accounting for subordinate team LMX mean suggests that high-quality LMX relationships with the team members supervised by the leader attenuates the negative relationship between LLX and leader TOI. Theoretical and practical contributions are discussed, including the importance of the relationship of LLX, LLX-D, and team LMX mean on employee attitudes at multiple organizational levels.
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Sung, Hsiao-li, and 宋小麗. "The Research of feasibility of High-level Manpower Dispatch." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/42rbyy.
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碩士<br>國立中山大學<br>高階經營碩士班<br>96<br>ABSTRACT
The manpower dispatch development in US, Japan and European country, all become mature industrial stage, in Taiwan also gradually develops under this tidal current, and gradually becomes one of frequently strategies adopt by the enterprise human resources department for human flexible scheduling. The manpower dispatch not only may provide the enterprise human resource in response to peak time or obtains the support of special specialized talented person, simultaneously can outside of administration responsibility, exempt from related cost for the employment of permanent staff, lets the enterprise have the extra mental effort to concentrates in its core specialty, therefore the enterprise get much attention and use it, further enhance its development of the enormous potential.
The manpower dispatch already is one of 12 prioritizes service industries in "service industry development guiding principle and the course of action" by the Economic Construction Committee of Executive Yuan, according to the industry and commerce general survey that held by DGBAS (Directorate-General of Budget, Accounting and Statistics) in 2001, there are approximately 790 manpower supplies industry, from the experiences of US, the manpower dispatch will be very important in the future duty field. According to the estimates of Economic Construction Committee, the average labor force are 9,900 thousand people in Taiwan, the dispatch laborer population might reach 300 thousand people in the future.
But recently, the type of knowledge worker change the manpower dispatch level (Yang Ch''aoan, 2004). Perhaps the dispatches worker''s image impression of most people is still the image of low-end manual worker, the administration worker or the sanitation worker, but the nowadays enterprise''s demand gradually transformed to technical role in specialist, high-level white-color worker as well as telecommunication ,marketing specialist.
At present in practice, some company runs the dispatch of tradition low level affairs or the labor work, some runs the recommendation or dispatch of the high step personnel (commonly knows as：head hunting) ,as for the high-level manpower dispatch that different from the dispatch of traditional dispatch and head hunting, in Europe/America and Japan had the explicit law definition and business volume, but in Taiwan is whether feasible? In the limit of not having enough literature for reference, this research attempts from the demand of enterprise, the supplies of high-level manpower, the barrier in practical and the economical scale of market, to analyze its feasibility, provides some reference for the dispatch industry.
This research discovered that：
(1) the high-level manpower dispatch truly has its demand in
Taiwan, and increases day by day.
(2) the supplies of the high-level manpower due to lack of protection of the law, presents recruits difficult and high turnover.
(3) the high-level manpower dispatches will match the expectation for both supply and demand sides (for example, the cognition of the employer, the trust, authorization and support to high-level dispatch manpower, and whether is willing to give reasonable service fee for which provides dispatch service) the challenge still many, was the key point of high-level manpower dispatch management.
(4) the business volume of high-level manpower dispatch at present in Taiwan is not enough, and is insufficient to support the dispatch industry to run this service only.
(5) the high-level manpower dispatch is feasible, and will be supposed to the mainstream of manpower dispatch market for the future.
Keyword: the manpower dispatch, the human resources, high-level manpower, dispatch demand enterprise
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Nguyen, Hoa. "What are country-level determinants of economic research productivity?" 2009. http://hdl.handle.net/10106/2080.
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Koerner, Craig Martin. "Explaining industry level R & D expenditures with a stock of knowledge variable /." 2000. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:9965106.
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YU, JENG-KAI, and 俞正凱. "A Research of Multi-Level Marketing Sells Join Decision Process." Thesis, 1995. http://ndltd.ncl.edu.tw/handle/68508649607213029333.
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Hu, Yi-Ping, and 胡逸斌. "Analysis Research in Behavioral Attributes of Middle/High Level Supervisors." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/21776243995006139253.
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碩士<br>元智大學<br>管理研究所<br>94<br>Unlike the other scholarly analysis or books about management studies and leadership influences, this paper focuses in examination the behavioral attributes of different level of supervisors. This paper also further analyzes the difference and the relationship of the behavioral attributes, the background stories and personalities of middle/high level supervisors and non-middle/high level supervisors.
With the analysis in this paper, the corporation could avoid the bias and blind spot when recruiting and promoting, in order to find a “real good supervisor” instead of a “supervisory supervisor”. Moreover, the individual who is currently in the management level could inspect himself or herself if one is classified within the range of “bore and unqualified supervisor”. The employee could also understand the ways to a qualified managerial supervisor.
According to the studies in this paper, the average ages of the first time being a managerial employee with annual salary over million dollars is between thirty-one to thirty-five years old; the stability of the middle/high level supervisors is better than the non-middle/high level supervisors; the most popular media when the middle/high level supervisors switch job are through internet (job bank), friends and relatives, and newspapers; some bosses or managers will judge an individual’s qualification according to one’s blood type and constellation, however, these are only bosses and managers’ personal preference. One’s background of “education level”, “oversea studies experience”, and “employment in multinational company” are the key factors that influence one’s potential to be a supervisor. Besides this, the direct relationship between the factors of “educational level of one’s father” and “one’s potential to be a supervisor” is positive correlation.
In the aspect of personal attributes, the middle/high level supervisors’ conscientiousness is high; emotional stability is better; creative; agreeableness is low but whose extroversion is unobvious. However, the extrinsic factors of the middle/high level supervisors are obvious. Thus, they will always make themselves ready to switch job even though their current jobs go smoothly.
In the aspect of one’s behavior and attributes, the middle/high level supervisors are good at one or more than one sports or hobbies, their time management is better than others, ones’ EQ and IQ are more outstanding. Overall, not only the job satisfaction is higher, their job involvement is also better. In additional, their communication ability is better and they are better at upward management. “Advise in advance and take responsibilities afterward” is their common philosophy in their upward management concepts.
The ranking of the elements of being a successful supervisor is “leadership”, “coherence”, “professional knowledge”, and “resistance to pressure”. The ranking of being a bore and unqualified middle/high level supervisor is “easy to break promise”, “arrogance”, and “obtrusive”. The ranking for the non-middle/high level supervisors is reverse; “arrogance” is major element of being a bore and unqualified supervisor.
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Chang, Cheng-Yu, and 張正裕. "A Research in High-Level Authentication for Wireless IP Networks." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/42538580688956498488.
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碩士<br>國立中興大學<br>電機工程學系<br>93<br>The need for wireless access to an IP network is evident. In order to offer uninterrupted wireless IP service combined with everywhere seamless mobility, the different network provider need to be integrated with each other. Therefore, efficient authentication and dynamic key exchange protocol that support heterogeneous domains is the key to the success of wide-area wireless IP infrastructures. In this thesis, first, we describe a multiprovider multitechnology wireless IP network infrastructure that meets for heterogeneity in network service providers, and bring up the requirements of authentication and key exchange protocol that operates in such a model should satisfy. Then we proposed a new idea that combines W-SKE with 2GR to design a new authentication scheme and dynamic key exchange protocol. The proposed authentication scheme can support roaming in a foreign domain. We use SPEARⅡ for the security analysis. From the simulation results, we know that the proposed scheme provides better efficiency as well as high security.
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Lee, Pin-Hui, and 李品慧. "Research on Beginner Level Japanese students’ Noun Measure Words Acquisition." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/08844106180864951761.
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碩士<br>中國文化大學<br>華語文教學碩士學位學程<br>104<br>Chinese and Japanese both are using measure words in their languages. Due to similarity in culture background,some of usage in these two languages are similar. Some of ways of using Chinese measure words and Japanese measure words are very similar, but some are with big difference. Sometimes, mistakes could happen easily for Japanese learners learning Chinese measure word. This could be related to their native language or just poor study in measure words. This research used questionnaires to target Japanese beginner students on using 15 measure words, then further analyzed the result.
The sample data is targeting on 65 Japanese beginner students in SooChow University and TLI institution. This analysis of questionnaires proved following three findings.
Firstly, although Japanese learner could make mistake on negative transfer on native language, but it is not the absolutely only reason. Secondly, as long as learners learned Chinese measure words in correct way, the mistake could be eliminated, Finally, Mandarin teacher can always use analysis of measure words to help learners to learn better. In the end, the author here made 3 suggestions base on this research. These are “Equip teaching skill for Mandarin teacher”, “Add Chinese measure words topic into teaching material”, and “Get support from teaching organization”
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Chu, Bing-Fang, and 祝冰芳. "Research on Intermediate Level Korean Learners’ Noun Measure Words Acquisition." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/92982328665157840828.
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碩士<br>國立臺北教育大學<br>語文與創作學系碩士班<br>103<br>Abstrct
Both Chinese and Korean have a rich system of measure words. Koreans are used to use measure words, but the similarities and differences between Chinese and Korean measure word systems contribute to the common errors made by Korean learners. Based on the language materials from Taiwan Chinese textbooks, and this study selected 35 noun measure words to design questionnaires, tests and interview. With this approach, measure word acquisitions of Korean learners were analyzed.
This comparative research aims to identify the causes and patterns of the usage errors made by Korean learners while learning Chinese measure words. According to the analyzed result “confused character pattern with literal meaning”, “ misapplied knowledge of Chinese words’ ”and “ impacts on negative transfer ” are the error types of Korean learners. In the end, this study draws up teaching propositions.
Keywords: Measure Word Acquisition, Chinese- Korean comparative analysis, the errors analysis, pedagogy of measure words
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Huang, Chi-Yang, and 黃智洋. "Research using level analytic method discussion green building material function." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/18149738486537739685.
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碩士<br>國立勤益科技大學<br>資訊管理系<br>102<br>Until today, people start to realize the Earth’s environment is confronted in potential Crisis. Such as the related building materials manufacture or during using process to produce the toxic substance, destruction the ozone layer and global warming. Those topics are gotten people’s attention let the Sustainable Development becomes globe’s values. Therefore, the manufactures develop the building materials which can improve environment. To ensure green building material has rightful performance and help consumers identify use. Building the complete verification system is the most important measure.
The profit splendor company uses recycle of the aluminum alloy material to become the main source material. They successively develop about green building materials. And also hope development for getting more integrity on the product line. To build up the company’s green building materials brand image. It will let in the architect, the room the designer, the correlation entrepreneur and the common populace that can one-stop shopping. This will meet each customer level the expense demand. This research’s goal is taking “the green building material function”. By the profit splendor art forging limited company for the case analysis. To discusses in the green building materials realization public works the practice experience situation. It will see how the green building materials’ doing on functional. And also If after market advocacy, will whether the popularity of usage.
This research mainly customer of acceptance in discussion green building material substitution existing tradition building materials, the research way first refers to the domestic and foreign correlation literature, by can construct suits gauging green building material it “the security”, “the natural resource use”, “the use” as well as “the energy conservation” and so on meter of the four big construction surface, according to the above does for gathers capital the material tool. Take the domestic green building material use manufacturer as the parent substance, take the random sampling way, fills in answers the way as direct interview filling in, after carries on the research analysis, in “the security”, reorganizes the main two major concepts is “the physiological building materials” and “chemistry building materials”; In “the natural resource use” the part, reorganizes the main two major concepts is “the rich resources” and “the green system regulation”; In “energy conservation” the part, reorganizes the main concept is “the resources circulation” and “the source decrement”; In “use” the part, reorganizes the main concept is “the high performance building materials”.Hoped may in use feasibility of influence factor the green building materials substitution tradition building materials in the green building material correlation industry constructs according to its attribute and the demand belongs to oneself enterprise culture the best serviceability.
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Wang, Chen-Pei, and 王振培. "Research on the level grouting method for weak soil tunnelling." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/00245620254939274601.
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碩士<br>中原大學<br>土木工程研究所<br>95<br>ABSTRACT
Keywords：ground improvement, level grouting
Many domestic constructions carried out in poor geologic conditions have taken the ground improvement as the first item of treatment, for the convenience of follow-up item.In the flabbiness stick to a soil layer carry on site improvement already have many work methods can be provided as reference usage, however Taipei mass transit Nei-Hou line CB420 block mark for domestic the shield tunnel cross an airport under it engineering, need to make an upper bound and a lower bound tunnel,and a connoction for averting imminent danger, because of construction district in Taipei Sungshan airport under it position special, and be subjected to only for flights careful condition, can't on the ground in traditional way get down make infuse syrup with carry on a soil layer of improvement is needing in already the completion the shield the tunnel infuse syrup by level of the way carry on a soil layer improvement a construction, this research introduction in Japan develop many usages of the double grid tube infuse syrup work method, its application is in Sungshan of airport apron under, shield tunnel up and down go a line contact channel site provement before making infuse syrup.
Airport site in Sungshan belongs to Taipei bottom of river in basin Keelung weak glue a soil layer, this research first explains this kind of pair grids tube infuses syrup site improvement of construction procedure method, then examine through infuse syrup to influence after improving the back it sticky the soil layer the strength and the rightness taxiway apron in the airport before.The description double in text grid tube infuses the improvement scope of the syrup work method site, infusing syrup part to make in proper order, the material go together with a ratio, use a machine tool equipment and infuse amount of Zhu etc., go to whole construction procedure and step content, and infuse syrup to assist with various monitors in the homework in the site improvement, in order to observe contact channel to make win various variety situation.
BE contacting the improvement completion of the channel site juniors to go structure to open to dig a construction, examine sticky the soil layer is after improving its close degree, through take out to measure sampling the soil body average strength to reach to a 523 kPa（5.23 kgf/cm2）, really reach construction technical specification big is 2 strength targets in the 200 kPa（2 kgf/ cm2）, the manifestation double grid tube infuse syrup site to improve a work method in the flabbiness sticky in the soil layer make result good, also very suitable for of special geography make, there is the advantage of construction convenience, can for thereafter meet similar geology condition and geography environment factor reference use.
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Yeh, Chia Lin, and 葉佳霖. "Research on Optimal Sequence of Two-level Blocked Factorial Design." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/14663725525257149670.
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碩士<br>長庚大學<br>工商管理學系<br>99<br>Blocked factorial experiments are considered for eliminating the Systematic sources of variations, such as the time and environment in factorial designs. Traditionally the higher-order interaction effects are used to be confounded with block effects. However, when the block size is small, we do not have enough high-order interaction effect for each purpose. Thus we need to carry out some blocks to estimate the treatment effects of interest.
This article focuses on blocking designs of two levels, and take the optimal blocking sequence by Jacroux (2006) proposed, we first find out the advantage of using orthogonal arrays to arrange this kind of experiments. We provide a fixed assigning rule to obtain the optimal blocking sequence for full factorial designs in orthogonal arrays and a catalogue to obtain the optimal blocking sequence for fractional factorial designs when the run size less than 32.
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Meng, Emma. "Compliance level to mobile health research application in cardiovascular patients." Thesis, 2019. https://hdl.handle.net/2144/36571.
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PURPOSE: This thesis intends to evaluate the factors which positively and negatively influence patient compliance to performing weekly home-based digital 6-minute-walk-tests (d6MWT) using a smartphone and smart watch.
PROBLEM: Long term patient engagement in mobile health apps have proven to be a challenge to maintain. In this thesis, factors that influence patient engagement will be identified when it comes to retaining participants that are using the VascTrac mobile health research application.
METHODS: Patient compliance will be calculated based on how many d6MWT are completed out of the expected total. The population is split into four levels of compliance groups from least compliant (0-25% compliance (Group A)) to most compliant (75.1-100% compliance (Group D)). “Open Walk” and survey data are collected and compared amongst these groups to see if there are any direct relationships that could be found. An “End of Study Survey” is also conducted to better understand the reasons behind differing compliance levels.
RESULTS: The overall compliance level is 66.1% for all comers with half of the patients scoring above 80%. Patients with higher compliance tend to have a higher weekly “Open Walk” average (correlation coefficient = 0.3). The average of weekly “Open Walk” is 0.53 walks/week.
CONCLUSION: Factors that negatively affect whether patients would be compliant to doing the weekly d6MWT are medical issues, technical difficulties, hospitalization, and lack of motivation. Being motivated and having a desire for self-improvement positively influences compliance levels. Decrease use of walking aids correlates to higher compliance and being smartphone naïve at beginning of study correlates to lower compliance. The other factors (age, co-morbidities, smoking habit, etc.) considered did not predict compliance levels.
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Das, Aritra. "Effect of Stimulus Normalization and Visual Attention at multiple scales of Neural Integration." Thesis, 2022. https://etd.iisc.ac.in/handle/2005/5986.
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The effect of visual attention on neural signals has been extensively studied using various techniques such as macaque neurophysiology and human electro/magneto encephalogram (EEG/MEG). Depending on the technique, different neural measures are typically used for studying attention. For example, in neurophysiology experiments involving macaques, many studies have focused on the modulation in spiking activity or the change in oscillatory power at different frequency bands such as alpha (8-12 Hz) or gamma (30-80 Hz) with attention, or the change in the relationship of spikes with these oscillations. In contrast, human EEG studies, in addition to studying alpha and gamma modulation, often use flickering stimuli that produce a specific neural response called steady-state visually evoked potential (SSVEP), which is also modulated by attention. However, due to the differences in stimuli and task paradigms in such studies, it is difficult to determine the effectiveness of these various neural measures for capturing attentional modulation. To address this, we designed a task paradigm which included both static and counterphase flickering stimuli to generate all the relevant neural measures (alpha/gamma power as well as SSVEPs) under identical recording conditions, which allowed us to compare their effectiveness in studying attention.
Since several reports suggest that attention modulates these neural measures through a canonical neural mechanism called normalization, in the first study of this thesis, we varied the normalization strength parametrically as a proxy for attentional modulation and tested its effect on various neural measures. We manipulated normalization strength by presenting static as well as flickering orthogonal superimposed gratings (plaids) at varying contrasts to two female monkeys while recording multiunit activity (MUA) and LFP from the primary visual cortex (area V1). We quantified the modulation in MUA, gamma (32-80 Hz), high-gamma (104-248 Hz) power, and SSVEP. Even under similar conditions, normalization strength was different for the four measures; and increased as: spikes, high-gamma, SSVEP, and gamma. However, these results could be explained using a normalization model, modified for population responses by varying the tuned normalization parameter and semi-saturation constant.
In the second part of the thesis, we tested the predictions of the gamma phase coding hypothesis in the context of stimulus contrast and visual attention. The gamma phase coding hypothesis posits that the intensity of the incoming stimulus is encoded in the position of the spike relative to the gamma rhythm. Using chronically implanted microelectrode arrays in the primary visual cortex of macaques engaged in an attention task while presenting stimuli of varying contrasts, we tested whether the phase of the gamma rhythm relative to spikes varied as a function of stimulus contrast and attentional state. We analyzed spikes and LFP from different electrodes and found a weak but significant effect of attention, but not stimulus contrast, on the gamma phase relative to spikes. Although we found a significant effect of attention, we argue that a small magnitude of phase shift as well as the dependence of phase angles on gamma power and center frequency, limits the potential role of gamma in phase coding in area V1.
In the third part of the thesis, we recorded EEG signals from 26 human participants while they were engaged in an attention task and analyzed alpha and gamma band powers for both static and flickering stimuli and SSVEP power for flickering stimuli. We report two main results. First, attentional modulation was comparable for SSVEP and alpha. Second, we found that non-foveal stimuli produced weak gamma despite various stimulus optimizations and therefore showed a negligible effect of attention although the same participants showed robust gamma activity for full-screen gratings. Thus, alpha and SSVEP won over gamma in capturing attentional modulation in human EEG. This result was in contrast to the findings of a comparable study in monkeys, where gamma and alpha won over SSVEPs. This study highlights the effectiveness of various neural measures in studying visual spatial attention and further implicates their usefulness in decoding behavior and attentional state in humans.<br>DBT-Wellcome Trust India Alliance (Grant IA/S/18/2/504003), Tata Trusts, DBT-IISc Partnership Programme