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671.
Automatic tracing and segmentation of rat mammary fat pads in MRI image sequences based on cartoon-texture model 总被引:1,自引:1,他引:0
The growth patterns of mammary fat pads and glandular tissues inside the fat pads may be related with the risk factors of breast cancer.Quantitative measurements of this relationship are available after segmentation of mammary pads and glandular tissues.Rat fat pads may lose continuity along image sequences or adjoin similar intensity areas like epidermis and subcutaneous regions.A new approach for automatic tracing and segmentation of fat pads in magnetic resonance imaging (MRI) image sequences is presented,which does not require that the number of pads be constant or the spatial location of pads be adjacent among image slices.First,each image is decomposed into cartoon image and texture image based on cartoon-texture model.They will be used as smooth image and feature image for segmentation and for targeting pad seeds,respectively.Then,two-phase direct energy segmentation based on Chan-Vese active contour model is applied to partitioning the cartoon image into a set of regions,from which the pad boundary is traced iteratively from the pad seed.A tracing algorithm based on scanning order is proposed to accurately trace the pad boundary,which effectively removes the epidermis attached to the pad without any post processing as well as solves the problem of over-segmentation of some small holes inside the pad.The experimental results demonstrate the utility of this approach in accurate delineation of various numbers of mammary pads from several sets of MRI images. 相似文献
672.
Alfred P. Rovai Mervyn J. Wighting Jason D. Baker Linda D. Grooms 《The Internet and Higher Education》2009,12(1):7-13
The purpose of this study was to develop and validate a self-report instrument that can be used to measure learning in the cognitive, affective, and psychomotor domains. The study underwent three phases, each with its own data collection and analysis. Phase I featured the development, testing, and factor analysis of an 80-item instrument that addressed cognitive, affective, and psychomotor learning that was administered to a sample of 142 online and face-to-face learners. Based on the results, the instrument was reduced to 21 items for Phase II and tested with a new sample of 171 online and face-to-face students. The results of confirmatory factor analysis suggested a better data fit with an even smaller 9-item instrument, which was then administered to a new sample of 221 online and face-to-face students in Phase III. The results of this final phase are presented along with the resulting CAP Perceived Learning Scale, a 9-item self-report measure of perceived cognitive, affective, and psychomotor learning. Implications and usage of the CAP Perceived Learning Scale for research and practice are also discussed. 相似文献
673.
Keith C. Herman Wendy M. Reinke Jason Parkin Karen B. Traylor Geetika Agarwal 《Psychology in the schools》2009,46(5):433-446
Schools play a privileged and strategic role in the lives of children acting as their principle environment away from home. Additionally, schools act as part of the community linking families and neighborhoods. These characteristics make schools a relevant setting for mental health service delivery and support to children and parents. In this article the role of the school environment on the development of childhood depression and as a leverage point in the prevention and treatment of depression will be discussed. Rationales for this viewpoint, as well as practical suggestions for reducing the deleterious effects of schooling on children's emotional well‐being, are offered. © 2009 Wiley Periodicals, Inc. 相似文献
674.
Jason J. Burrow‐Sanchez William R. Jenson Elaine Clark 《Psychology in the schools》2009,46(3):238-245
Experimentation with substances is typical for many young people, but unfortunately some will go on to develop substance abuse problems that substantially affect their lives. Successfully intervening with students who use or abuse substances is a challenge for school mental health professionals across the nation. There is a need for evidence‐based practices that school professionals can use when working with students who have substance abuse problems. This article provides school professionals in secondary settings with current information on student substance use rates, evidence‐based individual and group interventions, and discussion of the 42 Code of Federal Regulations, Part 2 (42 CFR). © 2008 Wiley Periodicals, Inc. 相似文献
675.
Paul C. Quinn Matthew M. Doran Jason E. Reiss and James E. Hoffman 《Child development》2009,80(1):151-161
Previous looking time studies have shown that infants use the heads of cat and dog images to form category representations for these animal classes. The present research used an eye-tracking procedure to determine the time course of attention to the head and whether it reflects a preexisting bias or online learning. Six- to 7-month-olds were familiarized with cats or dogs in upright or inverted orientations and then tested with a novel cat and novel dog in the same orientation. In the upright orientation, infants fixated head over body throughout familiarization; with inversion, no head preference was observed. These findings suggest that infant reliance on the head to categorize cats versus dogs results from a bias that pushes attention to the head. 相似文献
676.
Yi-Yuan Li Sara Ying Zhang Jason Zheng Jiang Simon Neild 《Journal of The Franklin Institute》2019,356(14):7836-7854
Vibration suppression capabilities of linear passive vibration absorbers, such as traditional tuned mass damper (TMD), and recently proposed inerter-based vibration absorbers, have been studied for multiple mechanical systems. In particular, significant performance advantages have been obtained with a specific device making use of both inerter and mass elements, namely the tuned mass damper inerter (TMDI). However, there are still countless mass-included inerter-based configurations that have not been studied, which can potentially provide more preferred dynamic properties. In this paper, an immittance-function-layout (IFL) is introduced, which can cover a large range of topological connection possibilities with both mass and inerter elements. With the recently proposed structural immittance format, a systematic approach is established to identify the most beneficial IFL type mass-included inerter-based configurations with pre-determined number of each element type. Vibration suppression performance with single-IFL type device and two parallel-connected IFLs (i.e. dual-IFL) type devices are investigated in this paper. Three optimal configurations are identified for mitigating the maximum inter-storey drift of an example 3-storey building model subjected to base excitation. With this 3-storey building model, results show that, for the optimum single-IFL configuration, the performance improvement is 7.3% compared with the optimum TMDI, and with identified beneficial dual-IFL configurations, up to 34.9% performance advantages are obtained. Furthermore, consistent performance gains are shown under real-life earthquake inputs and with a 10-storey building model using identified absorber configurations. 相似文献
677.
678.
Web sites often provide the first impression of an organization. For many organizations, web sites are crucial to ensure sales or to procure services within. When a person opens a web site, the first impression is probably made in a few seconds, and the user will either stay or move on to the next site on the basis of many factors. One of the factors that may influence users to stay or go is the page aesthetics. Another reason may involve a user’s judgment about the site’s credibility. This study explores the possible link between page aesthetics and a user’s judgment of the site’s credibility. Our findings indicate that when the same content is presented using different levels of aesthetic treatment, the content with a higher aesthetic treatment was judged as having higher credibility. We call this the amelioration effect of visual design and aesthetics on content credibility. Our study suggests that this effect is operational within the first few seconds in which a user views a web page. Given the same content, a higher aesthetic treatment will increase perceived credibility. 相似文献
679.
Automating the Construction of Internet Portals with Machine Learning 总被引:11,自引:0,他引:11
Andrew Kachites McCallum Kamal Nigam Jason Rennie Kristie Seymore 《Information Retrieval》2000,3(2):127-163
Domain-specific internet portals are growing in popularity because they gather content from the Web and organize it for easy access, retrieval and search. For example, www.campsearch.com allows complex queries by age, location, cost and specialty over summer camps. This functionality is not possible with general, Web-wide search engines. Unfortunately these portals are difficult and time-consuming to maintain. This paper advocates the use of machine learning techniques to greatly automate the creation and maintenance of domain-specific Internet portals. We describe new research in reinforcement learning, information extraction and text classification that enables efficient spidering, the identification of informative text segments, and the population of topic hierarchies. Using these techniques, we have built a demonstration system: a portal for computer science research papers. It already contains over 50,000 papers and is publicly available at www.cora.justresearch.com. These techniques are widely applicable to portal creation in other domains. 相似文献
680.
Research Findings: A growing emphasis in the literature on children’s self-regulation signals the need for increased understanding of the ways in which young children become active players in the acquisition of knowledge. In particular, self-regulation may be linked to subsequent academic achievement through greater engagement with the learning tasks and activities made available in the preschool classroom. This study tested preschoolers’ (N = 603) observed task engagement in the classroom as mediating the relations between directly assessed self-regulation and changes in their language and literacy outcomes during the preschool year. Findings indicate that self-regulation is directly related to observed task engagement as well as changes in a host of language and literacy skills. Engagement with tasks and activities in the classroom also partially mediates the association between self-regulation and changes in expressive vocabulary. Mediation through task engagement was not found for receptive language or early literacy skills. Practice or Policy: Findings suggest that the development and evaluation of clearly articulated preschool curricula designed to promote academic achievement by fostering self-regulation is an important direction for future research. 相似文献