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Retrieval, action and the representation of distance in cognitive mapsVann Bugmann, Davi January 2003 (has links)
This thesis examines the context effects on retrieval, and the influence of action on the representation of distance in cognitive maps. It is proposed that bias in distance estimation is a function of the contexts of retrieval that trigger the representation of action in memory during evaluation tasks. The proposal is consistent with embodied cognition evidence that suggests that actions are implicitly a part of the representation, and will be naturally extracted as part of the retrieval process. The experimental work presented examines two different contextual cues; the frequency of visitation to landmarks, and the importance of activity performed at landmarks. Each cue primes differently the conceptualisation of landmarks prior to making distance estimation. This priming facilitates memory access, which fleshes out relevant spatial information from cognitive maps that are used in distance estimation and route description. This proposal was examined in a series of four experiments that employed structured interviews. Participants had to rate landmarks based on frequency of visitation criteria or importance of activity criteria, or both. They then made verbal distance estimations and route descriptions. The results found implicate the involvement of action representation. The involvement of action in cognitive process was empirically investigated in three further experiments. A new methodology was developed featuring the use of a blindfold, linguistic descriptions, and control of actual movements. Blindfolded participants learned new environments through verbal descriptions by imagining themselves walking in time with the metronome beats. During turns, they were carefully moved. Following instructions, they performed an action at mid-route. Their memories for the newly learned environments were tested through recalls and measured again with the metronome beats. The results found were consistent with explanations based on network-map theory. They implicate attentional processes as an intrinsic part of the cognitive mechanism, and the strings of the network-map as the actual motor program that executes the movement. These results are discussed in relation to the nature of cognitive maps.
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Similarity Search in Continuous Data with Evolving Distance MetricZhang, Hauyi 12 December 2018 (has links)
Similarity search is a task fundamental to many machine learning and data analytics applications, where distance metric learning plays an important role. However, since modern online applications continuously produce objects with new characteristics which tend to change over time, state-of-the-art similarity search using distance metric learning methods tends to fail when deployed in such applications without taking the change into consideration.
In this work, we propose a Distance Metric Learning-based Continuous Similarity Search approach (CSS for short) to account for the dynamic nature of such data. CSS system adopts an online metric learning model to achieve distance metric evolving to adapt the dynamic nature of continuous data without large latency. To improve the accuracy of online metric learning model, a compact labeled dataset which is representative of the updated data is dynamically updated. Also, to accelerate similarity search, CSS includes an online maintained Locality Sensitive Hashing index to accelerate the similarity search.
One, our labeled data update strategy progressively enriches the labeled data to assure continued representativeness, yet without excessively growing its size to ensure that the computation costs of metric learning remain bounded. Two, our continuous distance metric learning strategy ensures that each update only requires one linear time k-NN search in contrast to the cubic time complexity of relearning the distance metric from scratch. Three, our LSH update mechanism leverages our theoretical insight that the LSH built based on the original distance metric is equally effective in supporting similarity search using the new distance metric as long as the transform matrix learned for the new distance metric is reversible. This important observation empowers CSS to avoid the modification of LSH in most cases. Our experimental study using real-world public datasets and large synthetic datasets confirms the effectiveness of CSS in improving the accuracy of classification and information retrieval tasks. Also, CSS achieves 3 orders of magnitude speedup of our incremental distance metric learning strategy (and its three underlying components) over the state-of-art methods.
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Comportement en fatigue d'un acier SAE 1045 revêtu de colmonoy 88 déposé par HVOF : effet de la distance de projection / Comportamiento a la fatiga del acero SAE 1045 recubierto con colmonoy 88 depositado por termorrociado HVOF : efecto de la distancia de rociado / Fatigue behavior of a SAE 1045 steel coated with colmonoy 88 deposited by HVOF thermal spraying : effect of spraying distanceLa Barbera Sosa, Jose Gregorio 01 December 2008 (has links)
L'influence de la distance de projection sur la microstructure et les propriétés mécaniques de l'alliage Colmonoy déposé par HVOF sur un acier SAE 1045 a été étudiée de manière systématique. La distance de projection varie entre 380 et 470 mm et les revêtements sont étudiés sur la surface et dans une section droite. L'analyse microstructurale est réalisée par MEB et par analyse d'images. Les différentes phases présentes dans le revêtement sont identifiées par diffraction des rayons X. Les contraintes résiduelles de surface sont déterminées par diffraction X en utilisant la méthode des sin[psi], l'analyse étant menée sur la famille de plans {311} de la phase du Nickel à environ 2[théta] ~ 93.2°. Les propriétés mécaniques des revêtements et des systèmes substrat/revêtement sont évaluées au moyen d'essais statiques et dynamiques. La dureté et le module d'élasticité des revêtements sont déterminés par nano-indentation utilisant un indenteur Berkovich et la méthode proposée par Oliver et Pharr. Les limites élastiques des revêtements sont aussi estimées à partir des courbes de chargement suivant la méthodologie de Zeng et Chiu en utilisant un indenteur bille et les équations de Hertz. Les propriétés mécaniques des systèmes substrat/revêtement sont déterminées par des essais de traction et de fatigue-corrosion sur des éprouvettes cylindriques. Les essais de fatigue corrosion ont été réalisés en flexion-rotation à une fréquence de 50 Hz dans une gamme de contraintes appliquées alternées entre 250 et 420 MPa, ceci dans une solution de NaCI à 3%. Les essais de fatigue-corrosion ont été conduits en utilisant des éprouvettes revêtues de chrome dur. / The influence of the spraying distance on the microstructure and mechanical properties of a Colmonoy 88 alloy deposited by means of HVOF thermal spraying onto a SAE 1045 steel substrate has been investigated in a systematic manner. The spraying distance varied between 380-470 mm and the deposits were evaluated both on their surface and cross section. The microstructural study was conducted by means of SEM and image analysis techniques. The different phases present in the deposits were identified by means of XRD. The surface residual stresses of the coatings were also determined employing the sin2[psi] method, the analysis being conducted on the (311) plane ofthe Ni phase, at 2[theta] ~ 93.2°. The mechanical properties of the coatings and substrate-coating systems were evaluated by means of static and dynamic mechanical tests of a different nature. Hardness and elastic modulus of the coatings were determined by means of instrumented indentation employing a Berkovich indenter and the methodology earlier proposed by Oliver and Pharr. The yield strength of the coatings was also estimated from the above curves following the methodology suggested by Zeng and Chiu, as well as from spherical indentation tests and the Hertz equations commonly used in contact mechanics. The mechanical properties of the substrate-coating system were evaluated by means of tensile and corrosion-fatigue tests employing cylindrical samples. Corrosion-fatigue tests were carried out under rotating-bending conditions at a frequency of 50 Hz, in the range of altemating stresses of 250-420 MPa, employing a of 3 wt% NaCI solution. Corrosion-fatigue tests were conducted employing steel samples coated with hard Cr.
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Perceptions of Persistence in a Community College English Composition ClassWatson, Starr 01 January 2019 (has links)
Abstract
The purpose of this bounded qualitative case study was to explore students' perceptions
of factors that influenced their success or failure in an online English composition course
at a community college located in the southeastern United States and to understand how
these factors affected their persistence in coursework. Retention rates in online for online
English composition courses are lower compared to face-to-face English composition
courses. Rapid expansion of online learning has led to increased concern regarding
student persistence in courses and degree or certification completion. Tinto's
interactionalist theory and Kember's model of student success framed the course of
inquiry for this study. Eight online student volunteers, who completed, failed, or
withdrew from a required entry-level English composition course, were purposefully
selected and individually interviewed using a semistructured format. Data were
thematically analyzed using open and pattern coding strategies and related to the
conceptual framework. Key results revealed student perceptions of factors that influenced
their success or failure in an online English composition course and suggested a change
in pedagogical practices to improve persistence as well as institutional and instructional
practices. Based on findings from this study, a white paper was drafted to present
stakeholders with a 2-pronged approach to improve student persistence featuring faculty
student engagement and meaningful action and reflection on student learning experiences
in an online English composition course. This study contributes to social change by
presenting a pedagogical shift to address a persistence problem in online English
composition courses. Persistence to course completion can build students' confidence and
keep them on a path to achieving their academic goals.
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Distance clinical supervision in cyberspace : a qualitative studyChristie, Bradley Scott 24 September 1998 (has links)
The purpose of this study was to determine the nature and process of clinical
supervision via the Internet as experienced by participating supervisees. The subjects of
this study were four students in a masters level internship course in counseling at
Oregon State University. The course was a pass/no pass counseling internship
placement which included an Internet-based clinical supervision component.
The qualitative design used in this study was based on a Constant Comparative
Methodology using coding categories developed manually and through the use of the
QSR NUDIST 3.0 Qualitative Data Analysis Software. This design focused on the
collection of textual material from participants engaged in distance clinical supervision.
This textual material and subsequent analysis served to help create an emergent theory
of distance clinical supervision.
Participants evidenced a motivation to participate in the distance supervision
experience and advanced not only clinical skill use but also were challenged with the
technological aspects of course participation. Findings suggest that the attitudes, prior
experiences, and social expectations influenced participant meaning-making and
subsequent self-construction of their ideal learning environment. In addition,
participants' interest in technology and the convenience of the distance venue provided
an impetus toward autonomous functioning in spite of supervisee dependency. This
struggle appeared consistent with the theoretical constructs of the developmental
models of supervisee process.
As supported by Stoltenberg's developmental model of supervisee development,
more advanced supervisees perform more autonomously. In this distance supervisory
environment, supervisees were offered additional opportunities to operate autonomously
which may impact overall supervisee development. This research may have
implications for the continued development of the distance supervision method
especially in experiential courses in the training of counselors. Recommendations and
cautions are offered for the further development of distance supervision courses as well
as the need for further research to substantiate the posited theoretical foundations. / Graduation date: 1999
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The critical role of faculty : applied frameworks and strategies for integrating distance education in postsecondary institutionsOlcott, Donald J. 07 December 1994 (has links)
This thesis asserts that faculty are the critical resource for the integration of distance
education by postsecondary institutions. The major barriers to the participation and
adoption of distance education center around faculty. This manuscript thesis incorporates a
series of articles to develop applied frameworks and strategies that place faculty at the core
of the institutional adoption process. An advocacy approach that integrates organizational
culture and diffusion of innovation theories provides a conceptual framework for
addressing the complex issues inducing faculty resistance to distance teaching. What
issues impact faculty receptivity to distance teaching? At the institutional level, altered
faculty roles for distance teaching, academic quality, inload vs overload teaching
assignments, promotion and tenure, quality of instructional and student support services,
and traditionally embedded academic norms affect faculty receptivity to distance teaching.
Moreover, this thesis asserts that institutional and interinstitutional extended degree
programs utilizing telecommunications must resolve issues related to curricular approval,
accreditation, program prioritization, academic residency, fee structures, and articulation.
Integrated instructional delivery frameworks are presented that fuse traditional instructional
systems with new learning systems. These frameworks advocate the gradual integration of
telecommunications-based coursework in extended degree programs to promote greater
faculty participation, expand curricular offerings for students, and balance the introduction
of new learning systems with traditional campus-based systems. A faculty support model
for integrating distance education in postsecondary institutions delineates the key
organizations and professionals essential to faculty and institutional adoption. This model
asserts that the centrality of faculty to distance teaching adoption requires mutual support
from presidents, deans, departmental chairpersons, the faculty senate, media services, and
continuing education. In conclusion, distance education compels postsecondary
institutions to reduce existing barriers to faculty participation by compensating, rewarding
and training faculty at levels commensurate with traditional instructional activities and to
provide instructional and administrative support services designed to ensure student access
to high quality programs. Without well trained and equitably rewarded distance teaching
faculty, the potential of distance education will be seriously diminished. Within the
mainstream academic culture, failure to ameliorate these human resource needs reduces
faculty receptivity to, and participation in, postsecondary distance teaching. Institutions
that satisfy these needs will simultaneously create a balanced equilibrium between the
application of advanced technologies and human resource development necessary for
ensuring instructional quality and student access to extended educational programs
delivered via distance education. / Graduation date: 1995
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Distance-learning receptivity differences between American and Korean graduate studentsKim, Jung Il 29 August 2005 (has links)
The purposes of this study were to determine if differences exist in distance-learning receptivity and perceived technology usefulness between American and Korean graduate students as well as Individualists and Collectivists. Results indicated that the two groups differed in distance-learning receptivity and perceived technology usefulness. However, cultural value tendency did not influence either receptivity or usefulness. Recommendations based on this study: 1. Researchers who are interested in cross-cultural field of distance learning should find what potential factors influence the differences in the receptivity and perceived usefulness between American and Korean group. 2. Administrators and decision makers who want to implement or adopt distance learning for their employees or students need to understand that cultural value, at least individualism and collectivism, is not a significant factor in distance learning. Instead, they should understand the importance of prior experience because people feel that distance is better than they??ve ever thought possible once they experience. 3. In implementing distance learning, practitioners should consider interactive media more than non-interactive media. Distance learning is mostly dependent upon technology. Practitioners should consider that distance-learning technology should be developed in terms of perceived usefulness to users. 4. In respect to usefulness, advanced and contemporary technologies were perceived more useful than traditional technologies in distance learning. Therefore, practitioners should also consider advanced technology rather than traditional technology in distance learning. Recommendations for future research: 1. It is suggested that Hofstede??s other cultural value dimensions should be included in future studies. 2. Future researchers should consider other factors such as personal background, learning style, skill level, and motivation. 3. Future research is needed to extend the current findings and test their generalizability to other types of users, for example, undergraduate students or organization employees. 4. This study used American and Korean samples only. Other national cultures should be tested with various cultural dimensions in a future study.
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Distance transformation on watershed applicationHsu, Wei-sheng 26 August 2010 (has links)
Euclidean Distance transformation and watershed are fundamental technique for the application fields of image understanding and computer vision. Calculated using the watershed transformation can be extracted important image features. Such as the identification of the contour and the number of such applications.
In this paper, we will compare the effects of our proposed watershed transform method and other watershed transformation method. Our proposed method will be more accurate. In image processing, object boundary segmentation is an important and fundamental issue.This study modified the traditional style of the watershed transformation,and we proposed the concept of an election-style, so that contact between the object image can be properly divided. By this method, image of objects can be converted according to the results of Euclidean distance transformation. It is easier to obtain images of various objects in the correct profile for easy application in medical image. Finally,we compare our methed with the National Institutes of Health (NIH) developed image processing software ImageJ, and marker-controlled watershed transformation of other scholars.
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Distance Labeling of PathsHuang, Rong-Shyang 30 July 2003 (has links)
none
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Distance-learning receptivity differences between American and Korean graduate studentsKim, Jung Il 29 August 2005 (has links)
The purposes of this study were to determine if differences exist in distance-learning receptivity and perceived technology usefulness between American and Korean graduate students as well as Individualists and Collectivists. Results indicated that the two groups differed in distance-learning receptivity and perceived technology usefulness. However, cultural value tendency did not influence either receptivity or usefulness. Recommendations based on this study: 1. Researchers who are interested in cross-cultural field of distance learning should find what potential factors influence the differences in the receptivity and perceived usefulness between American and Korean group. 2. Administrators and decision makers who want to implement or adopt distance learning for their employees or students need to understand that cultural value, at least individualism and collectivism, is not a significant factor in distance learning. Instead, they should understand the importance of prior experience because people feel that distance is better than they??ve ever thought possible once they experience. 3. In implementing distance learning, practitioners should consider interactive media more than non-interactive media. Distance learning is mostly dependent upon technology. Practitioners should consider that distance-learning technology should be developed in terms of perceived usefulness to users. 4. In respect to usefulness, advanced and contemporary technologies were perceived more useful than traditional technologies in distance learning. Therefore, practitioners should also consider advanced technology rather than traditional technology in distance learning. Recommendations for future research: 1. It is suggested that Hofstede??s other cultural value dimensions should be included in future studies. 2. Future researchers should consider other factors such as personal background, learning style, skill level, and motivation. 3. Future research is needed to extend the current findings and test their generalizability to other types of users, for example, undergraduate students or organization employees. 4. This study used American and Korean samples only. Other national cultures should be tested with various cultural dimensions in a future study.
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