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Sample records for led traditional storybook

  1. Taxonomies Support Preschoolers’ Knowledge Acquisition from Storybooks

    Directory of Open Access Journals (Sweden)

    Ashley M. Pinkham

    2014-01-01

    Full Text Available For young children, storybooks may serve as especially valuable sources of new knowledge. While most research focuses on how extratextual comments influence knowledge acquisition, we propose that children’s learning may also be supported by the specific features of storybooks. More specifically, we propose that texts that invoke children’s knowledge of familiar taxonomic categories may support learning by providing a conceptual framework through which prior knowledge and new knowledge can be readily integrated. In this study, 60 5-year olds were read a storybook that either invoked their knowledge of a familiar taxonomic category (taxonomic storybook or focused on a common thematic grouping (traditional storybook. Following the book-reading, children’s vocabulary acquisition, literal comprehension, and inferential comprehension were assessed. Children who were read the taxonomic storybook demonstrated greater acquisition of target vocabulary and comprehension of factual content than children who were read the traditional storybook. Inferential comprehension, however, did not differ across the two conditions. We argue for the importance of careful consideration of book features and storybook selection in order to provide children with every opportunity to gain the knowledge foundational for successful literacy development.

  2. Children Develop Initial Orthographic Knowledge during Storybook Reading

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    Apel, Kenn; Brimo, Danielle; Wilson-Fowler, Elizabeth B.; Vorstius, Christian; Radach, Ralph

    2013-01-01

    We examined whether young children acquire orthographic knowledge during structured adult-led storybook reading even though minimal viewing time is devoted to print. Sixty-two kindergarten children were read 12 storybook "chapters" while their eye movements were tracked. Results indicated that the children quickly acquired initial mental…

  3. Analysis of Technical Specifications of the Egyptian and French Electronic Storybooks (e-Storybook)

    Science.gov (United States)

    Atta, Mohammed Mahmoud; Abd El Wahab, Shaimaa Mahmoud

    2015-01-01

    This research aims at analysing technical specifications in a sample of Egyptian and French electronic storybooks (e-storybooks), to identify similarities and differences in technical specifications of children's e-storybooks and create a verified analysis list to be used for evaluation of e-storybooks. For this purpose, 32 e-storybooks in CD…

  4. The effect of enhanced storybook interaction on signing deaf children's vocabulary.

    Science.gov (United States)

    Trussell, Jessica W; Easterbrooks, Susan R

    2014-07-01

    The link between vocabulary and later literacy is well documented in the research base. One way children gain vocabulary is through incidental learning. Deaf or hard-of-hearing children (D/HH) often struggle with incidental learning and require vocabulary intervention to increase their lexicon. An effective vocabulary intervention is storybook reading. When dialogic methods are added to storybook reading, the gains are greater than with traditional storybook reading. The purpose of this study was to investigate the effect of an enhanced storybook reading intervention, which included scripted questions and picture prompts, on the vocabulary of young signing D/HH children. We utilized a multiple baseline across content probe design. We discovered a functional relation between the storybook intervention and picture vocabulary identification for several participants. This outcome offers insight into appropriate interventions to increase vocabulary for signing D/HH children. © The Author 2013. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  5. Cathedral outreach: student-led workshops for school curriculum enhancement in non-traditional environments

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    Posner, Matthew T.; Jantzen, Alexander; van Putten, Lieke D.; Ravagli, Andrea; Donko, Andrei L.; Soper, Nathan; Wong, Nicholas H. L.; John, Pearl V.

    2017-08-01

    Universities in the United Kingdom have been driven to work with a larger pool of potential students than just the more traditional student (middle-class white male), in order to tackle the widely-accepted skills-shortage in the fields of science, technology, engineering and mathematics (STEM), whilst honoring their commitment to fair access to higher education. Student-led outreach programs have contributed significantly to this drive. Two such programs run by postgraduate students at the University of Southampton are the Lightwave Roadshow and Southampton Accelerate!, which focus on photonics and particle physics, respectively. The program ambassadors have developed activities to enhance areas of the national curriculum through presenting fundamental physical sciences and their applications to optics and photonics research. The activities have benefitted significantly from investment from international organizations, such as SPIE, OSA and the IEEE Photonics Society, and UK research councils, in conjunction with university recruitment and outreach strategies. New partnerships have been formed to expand outreach programs to work in non-traditional environments to challenge stereotypes of scientists. This paper presents two case studies of collaboration with education learning centers at Salisbury Cathedral and Winchester Cathedral. The paper outlines workshops and shows developed for pupils aged 6-14 years (UK key stages 2-4) on the electromagnetic spectrum, particle physics, telecommunications and the human eye using a combination of readily obtainable items, hand-built kits and elements from the EYEST Photonics Explorer kit. The activities are interactive to stimulate learning through active participation, complement the UK national curriculum and link the themes of science with the non-traditional setting of a cathedral. We present methods to evaluate the impact of the activity and tools to obtain qualitative feedback for continual program improvement. We also

  6. Differences in eating behaviour, well-being and personality between mothers following baby-led vs. traditional weaning styles.

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    Brown, Amy

    2016-10-01

    Baby-led weaning, where infants self-feed family foods in place of traditional spoon-feeding of purees, is continuing to grow in popularity. Evidence is emerging which suggests that the method may promote healthier eating behaviour and weight gain in children, but the research is in its infancy. One issue is the self-selecting nature of participants to the approach. Although those who follow a baby-led approach are known to have a higher education and more professional occupation, little is known about wider maternal characteristics, which might affect either adoption of or outcomes of the method. The aim of this study was to explore differences in maternal characteristics between those adopting a baby-led or traditional approach. Six hundred four mothers with an infant aged 6-12 months completed a questionnaire including a copy of the Dutch Eating Behaviour Questionnaire (DEBQ), Brief Symptom Inventory (BSI) (anxiety, obsessive-compulsive and depression scales) and Ten Item Personality Questionnaire (TIPQ) alongside details of weaning approach (baby-led vs. traditional). Mothers who adopted a baby-led weaning style scored significantly lower on restrained eating (DEBQ), anxiety and introversion (TIPQ) and anxiety and obsessive-compulsive symptoms (BSI). Mothers who currently adopt a baby-led approach are therefore significantly different in personality, eating behaviour and well-being characteristics compared with those adopting a traditional approach. These characteristics may affect likelihood of choosing a baby-led approach or indirectly affect outcomes for infants weaned using the approach. Further research exploring baby-led weaning in a wider population sample is needed. © 2015 John Wiley & Sons Ltd.

  7. Using Storybooks as a Character Education Tools

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    Turan, Fethi; Ulutas, Ilkay

    2016-01-01

    This study aims to investigate the views and implementations of preschool teachers in "giving character education through picture storybooks." Descriptive review method was used in the research and supported with focus group interviews. For this reason data were took from two study groups (for the descriptive study group n = 245, for the…

  8. Development of Beliefs about Storybook Reality

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    Woolley, Jacqueline D.; Cox, Victoria

    2007-01-01

    The goal of this research was to assess children's beliefs about the reality status of storybook characters and events. In Experiment 1, 156 preschool age children heard realistic, fantastical, or religious stories, and their understanding of the reality status of the characters and events in the stories was assessed. Results revealed that…

  9. Storybook Reading for Young Dual Language Learners

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    Gillanders, Cristina; Castro, Dina C.

    2011-01-01

    Researchers widely recommend storybook reading for promoting the early language and literacy of young children. By listening to stories, children learn about written syntax and vocabulary and develop phonological awareness and concepts of print, all of which are closely linked to learning to read and write. Teachers usually know a read-aloud…

  10. Benefits and Pitfalls of Multimedia and Interactive Features in Technology-Enhanced Storybooks : A Meta-Analysis

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    Takacs, Zsofia K.; Swart, Elise K.; Bus, Adriana G

    2015-01-01

    A meta-analysis was conducted on the effects of technology-enhanced stories for young children's literacy development when compared to listening to stories in more traditional settings like storybook reading. A small but significant additional benefit of technology was found for story comprehension

  11. Comparison of an interactive CD-based and traditional instructor-led Basic Life Support skills training for nurses.

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    Mardegan, Karen J; Schofield, Margot J; Murphy, Gregory C

    2015-08-01

    Basic Life Support (BLS) is a life-saving and fundamental skill in resuscitation. However, studies have reported limitations in BLS training outcomes for both health professional and lay populations, and noted the resource and time-intensive nature of traditional training approaches. This exploratory study evaluated the effectiveness of an interactive CD-based BLS training programme that included unsupervised manikin practice compared with a traditional instructor-led BLS training programme involving demonstration and supervised practice. A quasi-experimental post-test with follow-up design was used. The sample was comprised of two cohorts: Novice second-year undergraduate Nursing students (n=187) and Practising Nurses (n=107) in their first year of hospital employment. BLS skill outcomes were assessed at one week and again at eight weeks post training. No statistically significant differences were found between the CD and traditional instructor-led BLS training methods in BLS skills of Novice and Practising Nurses at one week and eight weeks post training. However, there was a decrement in skill between one week and eight weeks post-training across both groups and an overall low level of competence. The failure to find a difference between the CD-based BLS programme with unsupervised manikin practice and a resource-intensive traditional instructor-led BLS training programme may indicate equivalence of the programmes or, even study design limitations. It is concerning that competence displayed by trainees from both groups was less than optimal and suggests the need for renewed efforts to develop and evaluate BLS training programmes which can achieve high rates of competence with acceptable skill retention over time. Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.

  12. Storybook app creation demystified a cast study

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    Friedlander, Amy

    2013-01-01

    This case study explains how Wasabi Productions created its first app, Lazy Larry Lizard, and provides insight into the development of soon-to-be-released app, Gorilla Band. Inside, you will find notes on how storybook apps are produced from start to finish, including costs, production process, people, technology, pricing, release cycle, marketing and more. You will also find insights on technology, storyboard development and pricing.

  13. Interactive storybook-based intervention effects on kindergartners' language development

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    Druten-Frietman, L.J.G. van; Strating, H.T.; Denessen, E.J.P.G.; Verhoeven, L.T.W.

    2016-01-01

    A dialogic storybook-based intervention integrating dialogic storybook reading with early literacy activities is studied with a longitudinal quasi-experimental study design. The effects of this intervention, in addition to a regular early childhood education (ECE) program, on kindergartners'

  14. Interactive Storybook-Based Intervention Effects on Kindergartners' Language Development

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    van Druten-Frietman, Loes; Strating, Heleen; Denessen, Eddie; Verhoeven, Ludo

    2016-01-01

    A dialogic storybook-based intervention integrating dialogic storybook reading with early literacy activities is studied with a longitudinal quasi-experimental study design. The effects of this intervention, in addition to a regular early childhood education (ECE) program, on kindergartners' vocabulary and phonological awareness development are…

  15. Young Second Language Learners' Visual Attention to Illustrations in Storybooks

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    Verhallen, Marian J. A. J.; Bus, Adriana G.

    2011-01-01

    The major purpose of this study was to test how preliterate learners use illustrations in storybooks to understand a story. Subjects were 23 five-year-old low-SES children, learning Dutch as a second language. Each child was exposed four times to a digital picture storybook. Five books were used and counterbalanced over children and repetitions.…

  16. Live Storybook Outcomes of Pilot Multidisciplinary Elementary Earth Science Collaborative Project

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    Soeffing, C.; Pierson, R.

    2017-12-01

    Live Storybook Outcomes of pilot multidisciplinary elementary earth science collaborative project Anchoring phenomena leading to student led investigations are key to applying the NGSS standards in the classroom. This project employs the GLOBE elementary storybook, Discoveries at Willow Creek, as an inspiration and operational framework for a collaborative pilot project engaging 4th grade students in asking questions, collecting relevant data, and using analytical tools to document and understand natural phenomena. The Institute of Global Environmental Strategies (IGES), a GLOBE Partner, the Outdoor Campus, an informal educational outdoor learning facility managed by South Dakota Game, Fish and Parks, University of Sioux Falls, and All City Elementary, Sioux Falls are collaborating partners in this project. The Discoveries at Willow Creek storyline introduces young students to the scientific process, and models how they can apply science and engineering practices (SEPs) to discover and understand the Earth system in which they live. One innovation associated with this project is the formal engagement of elementary students in a global citizen science program (for all ages), GLOBE Observer, and engaging them in data collection using GLOBE Observer's Cloud and Mosquito Habitat Mapper apps. As modeled by the fictional students from Willow Creek, the 4th grade students will identify their 3 study sites at the Outdoor Campus, keep a journal, and record observations. The students will repeat their investigations at the Outdoor Campus to document and track change over time. Students will be introduced to "big data" in a manageable way, as they see their observations populate GLOBE's map-based data visualization and . Our research design recognizes the comfort and familiarity factor of literacy activities in the elementary classroom for students and teachers alike, and postulates that connecting a science education project to an engaging storybook text will contribute to a

  17. Design of Multimedia-based Digital Storybooks for Preschool Education

    Directory of Open Access Journals (Sweden)

    Didik Dwi Prasetya

    2018-02-01

    Full Text Available Storytelling is one of the suitable approaches to deliver the right information and build the character education of young children. The story content presented by utilizing multimedia elements is able to offer more attractive and increase interest for children. This paper proposes an ICT approach through multimedia-based digital storybook design with an EPUB reflowable format that can be accessed using various electronic devices, whether desktop, laptop, or mobile. The research subjects are limited to 4-5-year-old preschool children. The research reveals that children were very enthusiastic about storybooks, with or without supports from teachers

  18. Emotion displays in media: a comparison between American, Romanian, and Turkish children's storybooks

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    Wege, Briana Vander; Sánchez González, Mayra L.; Friedlmeier, Wolfgang; Mihalca, Linda M.; Goodrich, Erica; Corapci, Feyza

    2014-01-01

    Children's books may provide an important resource of culturally appropriate emotions. This study investigates emotion displays in children's storybooks for preschoolers from Romania, Turkey, and the US in order to analyze cultural norms of emotions. We derived some hypotheses by referring to cross-cultural studies about emotion and emotion socialization. For such media analyses, the frequency rate of certain emotion displays can be seen as an indicator for the salience of the specific emotion. We expected that all children's storybooks would highlight dominantly positive emotions and that US children's storybooks would display negative powerful emotions (e.g., anger) more often and negative powerless emotions (e.g., sadness) less often than Turkish and Romanian storybooks. We also predicted that the positive and negative powerful emotion expressions would be more intense in the US storybooks compared to the other storybooks. Finally, we expected that social context (ingroup/outgroup) may affect the intensity emotion displays more in Turkish and Romanian storybooks compared to US storybooks. Illustrations in 30 popular children's storybooks (10 for each cultural group) were coded. Results mostly confirmed the hypotheses but also pointed to differences between Romanian and Turkish storybooks. Overall, the study supports the conclusion that culture-specific emotion norms are reflected in media to which young children are exposed. PMID:24987384

  19. No difference in self-reported frequency of choking between infants introduced to solid foods using a baby-led weaning or traditional spoon-feeding approach.

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    Brown, A

    2017-12-05

    Baby-led weaning (BLW) where infants self-feed family foods during the period that they are introduced to solid foods is growing in popularity. The method may promote healthier eating patterns, although concerns have been raised regarding its safety. The present study therefore explored choking frequency amongst babies who were being introduced to solid foods using a baby-led or traditional spoon-fed approach. In total, 1151 mothers with an infant aged 4-12 months reported how they introduced solid foods to their infant (following a strict BLW, loose BLW or traditional weaning style) and frequency of spoon-feeding and puree use (percentage of mealtimes). Mothers recalled if their infant had ever choked and, if so, how many times and on what type of food (smooth puree, lumpy puree, finger food and specific food examples). In total, 13.6% of infants (n = 155) had ever choked. No significant association was found between weaning style and ever choking, or the frequency of spoon or puree use and ever choking. For infants who had ever choked, infants following a traditional weaning approach experience significantly more choking episodes for finger foods (F 2,147  = 4.417, P = 0.014) and lumpy purees (F 2,131  = 6.46, P = 0.002) than infants following a strict or loose baby-led approach. Baby-led weaning was not associated with increased risk of choking and the highest frequency of choking on finger foods occurred in those who were given finger foods the least often. However, the limitations of noncausal results, a self-selecting sample and reliability of recall must be emphasised. © 2017 The British Dietetic Association Ltd.

  20. The African Storybook and Language Teacher Identity in Digital Times

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    Stranger--Johannessen, Espen; Norton, Bonny

    2017-01-01

    The African Storybook (ASb) is a digital initiative that promotes multilingual literacy for African children by providing openly licenced children's stories in multiple African languages, as well as English, French, and Portuguese. Based on Darvin and Norton's (2015) model of identity and investment, and drawing on the Douglas Fir Group's (2016)…

  1. ELL Preschoolers' English Vocabulary Acquisition from Storybook Reading

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    Collins, Molly F.

    2010-01-01

    This study investigates the effects of rich explanation, baseline vocabulary, and home reading practices on English language learning (ELL) preschoolers' sophisticated vocabulary learning from storybook reading. Eighty typically developing preschoolers were pretested in L1 (Portuguese) and L2 (English) receptive vocabulary and were assigned to…

  2. Improving Grade One Students' Reading Motivation with Online Electronic Storybooks

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    Ciampa, Katia

    2012-01-01

    This qualitative study stemmed from a concern of the perceived decline in students' reading motivation after the early years of schooling. The current research explored eight grade 1 students' experiences with online electronic storybooks (eBooks). Eight students were given ten 25-minute sessions with the software programs over 15 weeks.…

  3. Interactive electronic storybooks for kindergartners to promote vocabulary growth

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    Smeets, Daisy J. H.; Bus, Adriana G

    2012-01-01

    The goals of this study were to examine (a) whether extratextual vocabulary instructions embedded in electronic storybooks facilitated word learning over reading alone and (b) whether instructional formats that required children to invest more effort were more effective than formats that required

  4. Who believes in the storybook image of the scientist?

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    Veldkamp, C.L S; Hartgerink, C.H.J.; van Assen, M.A.L.M.; Wicherts, J.M.

    2017-01-01

    Do lay people and scientists themselves recognize that scientists are human and therefore prone to human fallibilities such as error, bias, and even dishonesty? In a series of three experimental studies and one correlational study (total N = 3,278) we found that the 'storybook image of the

  5. Who Believes in the Storybook Image of the Scientist?

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    Veldkamp, Coosje L S; Hartgerink, Chris H J; van Assen, Marcel A.L.M.; Wicherts, Jelte M.

    2017-01-01

    Do lay people and scientists themselves recognize that scientists are human and therefore prone to human fallibilities such as error, bias, and even dishonesty? In a series of three experimental studies and one correlational study (total N = 3,278) we found that the “storybook image of the

  6. The use of Julia Donaldson’s storybooks as an incentive to actively acquire foreign language in the 1st grade of primary school

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    Stošič, Ana

    2017-01-01

    Learning foreign languages in early childhood is very specific, therefore, teaching must take place according to certain principles. The acquisition of a foreign language should happen through games and movement activities. Moreover, the purpose of learning and teaching a foreign language in the first grade is also to encourage a positive attitude towards other languages. Storybooks are classified as basic teaching means or materials and storytelling is a traditional, tested (from folk litera...

  7. Goodnight book: sleep consolidation improves word learning via storybooks

    Science.gov (United States)

    Williams, Sophie E.; Horst, Jessica S.

    2014-01-01

    Reading the same storybooks repeatedly helps preschool children learn words. In addition, sleeping shortly after learning also facilitates memory consolidation and aids learning in older children and adults. The current study explored how sleep promotes word learning in preschool children using a shared storybook reading task. Children were either read the same story repeatedly or different stories and either napped after the stories or remained awake. Children's word retention were tested 2.5 h later, 24 h later, and 7 days later. Results demonstrate strong, persistent effects for both repeated readings and sleep consolidation on young children's word learning. A key finding is that children who read different stories before napping learned words as well as children who had the advantage of hearing the same story. In contrast, children who read different stories and remained awake never caught up to their peers on later word learning tests. Implications for educational practices are discussed. PMID:24624111

  8. Goodnight Book: Sleep Consolidation Improves Word Learning via Storybooks

    Directory of Open Access Journals (Sweden)

    Sophie E. Williams

    2014-03-01

    Full Text Available Reading the same storybooks repeatedly helps preschool children learn words. In addition, sleeping shortly after learning also facilitates memory consolidation and aids learning in older children and adults. The current study explored how sleep promotes word learning in preschool children using a shared storybook reading task. Children were either read the same story repeatedly or different stories and either napped after the stories or remained awake. Children’s word retention were tested 2.5 hours later, 24 hours later and 7 days later. Results demonstrate strong, persistent effects for both repeated readings and sleep consolidation on young children’s word learning. A key finding is that children who read different stories before napping learned words as well as children who had the advantage of hearing the same story. In contrast, children who read different stories and remained awake never caught up to their peers on later word learning tests. Implications for educational practices are discussed.

  9. Preschoolers Explore Interactive Storybook Apps: The Effect on Word Recognition and Story Comprehension

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    Zipke, Marcy

    2017-01-01

    Two experiments explored the effects of reading digital storybooks on tablet computers with 25 preschoolers, aged 4-5. In the first experiment, the students' word recognition scores were found to increase significantly more when students explored a digital storybook and employed the read-aloud function than when they were read to from a comparable…

  10. The Effect of Thematically Related Play on Engagement in Storybook Reading in Children with Hearing Loss

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    Pataki, Kristen W.; Metz, Alexia E.; Pakulski, Lori

    2014-01-01

    Purpose: This study examined whether theme-related play increased subsequent engagement in storybook reading in preschool children with typical hearing and with hearing loss. Method: This study employed a counterbalanced experimental design. In all sessions, participants engaged in free play first and then were read a storybook. In the…

  11. Multimedia Storybooks: Supporting Vocabulary for Students Who Are Deaf/Hard-of-Hearing

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    Donne, Vicki; Briley, Margaret L.

    2015-01-01

    A single case study examined the use of multimedia storybooks on the vocabulary acquisition of 7 preschool students who are deaf/hard of hearing in two classrooms at a school for the deaf in the U.S. Participants also included 3 speech-language pathologists. Students spent an average of 7.1 minutes daily working with the multimedia storybooks and…

  12. Their Teacher Can't Be an App: Preschoolers' Listening Comprehension of Digital Storybooks

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    Paciga, Kathleen A.

    2015-01-01

    This study sought to determine the relationship among student- and task-level variables at play in the digital storybook listening experiences of 130 English-speaking preschoolers at risk of reading failure. Specifically, this study investigated the relationship among the (1) features of computer-based electronic storybooks, (2) preschoolers'…

  13. The Differential Effect of Storybook Reading on Preschoolers' Acquisition of Expressive and Receptive Vocabulary.

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    Senechal, Monique

    1997-01-01

    Evaluates the effect of didactic techniques used during storybook reading on young children's acquisition of new vocabulary introduced in storybooks under three reading conditions: single-reading; repeated-reading and questioning. Findings suggest that didactic techniques used by adults have differential effects on preschoolers' receptive and…

  14. Interactive electronic storybooks for kindergartners to promote vocabulary growth.

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    Smeets, Daisy J H; Bus, Adriana G

    2012-05-01

    The goals of this study were to examine (a) whether extratextual vocabulary instructions embedded in electronic storybooks facilitated word learning over reading alone and (b) whether instructional formats that required children to invest more effort were more effective than formats that required less effort. A computer-based "assistant" was added to electronic storybooks. The assistant posed extratextual vocabulary questions. Questions were presented in a multiple-choice format so that children could respond by clicking on the picture that best represented the target word. In Experiment 1 (N=20), children read stories with and without questions. Children learned more words when reading with questions than without. Expressive vocabulary was particularly affected by question insertion. In Experiment 2 (N=27), we used two methods for teaching words: one requiring more effort on the part of children (questions) and one requiring less effort ("hotspots" that provide definitions). Results revealed that questions were more beneficial than just providing a definition or synonym of the target word. Implications for designing new e-book apps are discussed. Copyright © 2011 Elsevier Inc. All rights reserved.

  15. "What's wrong with grandma?": depictions of Alzheimer's disease in children's storybooks.

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    Sakai, Erin Y; Carpenter, Brian D; Rieger, Rebecca E

    2012-12-01

    Alzheimer's disease (AD) affects the entire family system, including young children. Yet there are few resources to help children understand AD. Storybooks are used to educate children about other diseases and may be useful in AD as well. In this study, we examined the depiction of AD in 33 English-language children's storybooks written specifically about AD. As a group, storybooks present AD as a brain disease, but provide little information about the diagnostic process or treatments. Clinical presentations are diverse among characters with AD, and no single book presents a comprehensive depiction of the cognitive, behavioral, affective, and functional symptoms of the disease. In fact, the prevalence of some symptoms in this "population" of storybook characters diverges substantially from epidemiological reports. Books designed to familiarize children about AD should be comprehensive and accurate. Current resources, while useful, could be improved to ensure health literacy about AD in young children.

  16. Digital life storybooks for people with dementia living in care homes: an evaluation

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    Subramaniam P

    2016-09-01

    Full Text Available Ponnusamy Subramaniam,1 Bob Woods2 1Health Psychology Programme, University Kebangsaan Malaysia, Kuala Lumpur, Malaysia; 2Dementia Services Development Centre Wales, Bangor University, Bangor, Gwynedd, UK Background and aim: There is increasing interest in using information and communication technology to help older adults with dementia to engage in reminiscence work. Now, the feasibility of such approaches is beginning to be established. The purpose of this study was to establish an evidence-base for the acceptability and efficacy of using multimedia digital life storybooks with people with dementia in care homes, in comparison with conventional life storybooks, taking into account the perspectives of people with dementia, their relatives, and care staff.Methods: Participatory design was used to create a life story movie based on a previously completed conventional life storybook with six older adults with dementia (four females; mean age 82 years. Relatives were involved in helping the participant to provide additional information and materials for the digital life storybook. In this multiple case study design, both quantitative and qualitative approaches were used. For quantitative purposes, a set of questionnaires that had been completed three times before and after the conventional life storybook was developed were repeated 4 weeks after the life story movie was completed. Semistructured interview questions were designed to collect feedback from participants, relatives, and care staff.Results: The result indicated that five of the six participants showed additional improvement in measures of quality of life and autobiographical memory. All participants showed improvement or stability in depression scores. Thematic analysis showed that, participants, relatives, and care home staff viewed digital life storybooks as a very useful tool triggering memories and (largely positive emotions. Participants’ case vignettes were presented to

  17. Get the story straight: contextual repetition promotes word learning from storybooks

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    Jessica S Horst

    2011-02-01

    Full Text Available Although reading storybooks to preschool children is a common activity believed to improve language skills, how children learn new vocabulary from being to has been largely neglected in the shared storybook reading literature. The current study systematically explores the effects of repeatedly reading the same storybooks on both young children's fast and slow mapping ability. Specially created storybooks were read to 3-year-old children three times during the course of one week. Each of the nine storybooks contained two novel word-object pairs. At each session, children either heard three different stories with the same two novel name-object pairs or the same story three times. All children heard each novel name the same number of times. A four-alternative forced-choice task with pictures of the objects was used to test both immediate recall and retention. Children who heard the same stories repeatedly were very accurate on both the immediate recall and retention tasks. In contrast, children who heard different stories were only accurate on immediate recall during the last two sessions and failed to learn any of the new words. Overall, then, we found a dramatic increase in children’s ability to both recall and retain novel word-object associations encountered during shared storybook reading when they heard the same stories multiple times in succession. Results are discussed in terms of contextual cueing effects observed in other cognitive domains.

  18. Integrating American Indian/alaska Native culture into shared storybook intervention.

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    Inglebret, Ella; Jones, Carla; Pavel, D Michael

    2008-10-01

    The purpose of this clinical exchange is to provide information for speech-language pathologists (SLPs) so they will be able to provide culturally responsive intervention for young children of American Indian and Alaska Native heritage. The focus is on a particular strategy--the integration of culturally based stories into shared storybook intervention. The use of culturally based stories is presented as it relates to sociocultural theory and the expressed priority of Native peoples to revitalize their cultural teaching and learning practices, inclusive of storytelling. Strategies are presented that SLPs can follow in preparing for the use of culturally based stories, as well as in ensuring that the stories that are selected for use are authentic and appropriate for the children involved. The strategies discussed represent the collaborative efforts of Native and non-Native professionals to link a review of pertinent scholarly literature with ancestral knowledge that is derived from tribal elders and tradition bearers of the Southern Puget Salish peoples. The article concludes by illustrating the application of these strategies to a program involving young children of culturally and linguistically diverse backgrounds. SLPs can integrate culturally based stories into their language and literacy intervention to encourage American Indian and Alaska Native children.

  19. Observation of directional storybook reading influences young children's counting direction.

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    Göbel, Silke M; McCrink, Koleen; Fischer, Martin H; Shaki, Samuel

    2018-02-01

    Even before formal schooling, children map numbers onto space in a directional manner. The origin of this preliterate spatial-numerical association is still debated. We investigated the role of enculturation for shaping the directionality of the association between numbers and space, focusing on counting behavior in 3- to 5-year-old preliterate children. Two studies provide evidence that, after observing reading from storybooks (left-to-right or right-to-left reading) children change their counting direction in line with the direction of observed reading. Just observing visuospatial directional movements had no such effect on counting direction. Complementarily, we document that book illustrations, prevalent in children's cultures, exhibit directionality that conforms to the direction of a culture's written language. We propose that shared book reading activates spatiotemporal representations of order in young children, which in turn affect their spatial representation of numbers. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Perfect Prophets, Helpful Hippos, and Happy Endings: Noah and Jonah in Children's Bible Storybooks in the United States

    Science.gov (United States)

    Dalton, Russell W.

    2007-01-01

    This article is based on a study of hundreds of children's bible storybooks available in the United States from 1850 to the present and focuses on the way the biblical stories of Noah and Jonah have been retold for children. These children's bible storybooks lend insight into the American church's changing assumptions about the purpose of the…

  1. Effects of Automated Tier 2 Storybook Intervention on Vocabulary and Comprehension Learning in Preschool Children with Limited Oral Language Skills

    Science.gov (United States)

    Kelley, Elizabeth Spencer; Goldstein, Howard; Spencer, Trina D.; Sherman, Amber

    2015-01-01

    This early efficacy study examined the effects of an automated storybook intervention designed to promote school readiness among at-risk prekindergarten children. Story Friends is a small-group intervention in which vocabulary and question-answering lessons are embedded in a series of storybooks.A randomized group design with an embedded…

  2. Seeing and Knowing: Attention to Illustrations during Storybook Reading and Narrative Comprehension in 2-Year-Olds

    Science.gov (United States)

    Kaefer, Tanya; Pinkham, Ashley M.; Neuman, Susan B.

    2017-01-01

    Research (Evans & Saint-Aubin, 2005) suggests systematic patterns in how young children visually attend to storybooks. However, these studies have not addressed whether visual attention is predictive of children's storybook comprehension. In the current study, we used eye-tracking methodology to examine two-year-olds' visual attention while…

  3. I think I can: Achievement-oriented themes in storybooks from Indonesia, Japan, and the United States

    Directory of Open Access Journals (Sweden)

    Maria eSuprawati

    2014-03-01

    Full Text Available The focus of the present study is on the ways in which storybooks communicate cultural ideals about achievement orientation, and in particular, the role of effort, perseverance, and hard work in fostering successful outcomes. Sixty preschool children’s books from Indonesia, Japan, and the United States (20 from each country were examined for the presence of achievement-oriented themes. These countries were chosen due to previously documented cultural differences in models of learning and individualist/collectivist tendencies that could have some bearing on achievement outcomes. Texts were assessed for (1 the frequency with which challenge events appeared in the narratives, (2 whether these events derived from sources internal or external to the main character, and (3 whether solutions relied on the main character individually or included the assistance of others. Results show that Japanese storybooks contained significantly more challenge events than Indonesian storybooks. Compared with Japanese storybooks, American storybooks tended to include a greater proportion of challenges derived from internal qualities of the main character as opposed to external factors. Compared with American storybooks, Japanese storybooks contained a significantly greater proportion of challenges that were solved with individual efforts as opposed to efforts involving the assistance of others. Findings from this study contribute to our understanding of how storybook contexts can provide a rich source of information for young children learning about culturally valued qualities and behaviors related to achievement.

  4. “I think I can”: achievement-oriented themes in storybooks from Indonesia, Japan, and the United States

    Science.gov (United States)

    Suprawati, Maria; Anggoro, Florencia K.; Bukatko, Danuta

    2013-01-01

    The focus of the present study is on the ways in which storybooks communicate cultural ideals about achievement orientation, and in particular, the role of effort, perseverance, and hard work in fostering successful outcomes. Sixty preschool children's books from Indonesia, Japan, and the United States (20 from each country) were examined for the presence of achievement-oriented themes. These countries were chosen due to previously documented cultural differences in models of learning and individualist/collectivist tendencies that could have some bearing on achievement outcomes. Texts were assessed for (1) the frequency with which “challenge events” appeared in the narratives, (2) whether these events derived from sources internal or external to the main character, and (3) whether solutions relied on the main character individually or included the assistance of others. Results show that Japanese storybooks contained significantly more challenge events than Indonesian storybooks. Compared with Japanese storybooks, American storybooks tended to include a greater proportion of challenges derived from internal qualities of the main character as opposed to external factors. Compared with American storybooks, Japanese storybooks contained a significantly greater proportion of challenges that were solved with individual efforts as opposed to efforts involving the assistance of others. Findings from this study contribute to our understanding of how storybook contexts can provide a rich source of information for young children learning about culturally valued qualities and behaviors related to achievement. PMID:24624105

  5. Clinical Impact of Wordless Picture Storybooks on Bilingual Narrative Language Production: A Comparison of the "Frog" Stories

    Science.gov (United States)

    Heilmann, John J.; Rojas, Raúl; Iglesias, Aquiles; Miller, Jon F.

    2016-01-01

    Background: Language sampling, recognized as a gold standard for expressive language assessment, is often elicited using wordless picture storybooks. A series of wordless storybooks, commonly referred to as "Frog" stories, have been frequently used in language-based research with children from around the globe. Aims: To examine the…

  6. It Depends: Conditional Correlation between Frequency of Storybook Reading and Emergent Literacy Skills in Children with Language Impairments

    Science.gov (United States)

    Petrill, Stephen A.; Logan, Jessica A. R.; Sawyer, Brook E.; Justice, Laura M.

    2014-01-01

    The current study examined the association between frequency of storybook reading and emergent literacy in 212 children at risk for language impairment, assessed during the fall semester of kindergarten. Measures included parent-reported storybook reading, as well as direct assessments of print knowledge, letter awareness, and expressive…

  7. A Hybrid Integrated Laboratory and Inquiry-Based Research Experience: Replacing Traditional Laboratory Instruction with a Sustainable Student-Led Research Project

    Science.gov (United States)

    Hartings, Matthew R.; Fox, Douglas M.; Miller, Abigail E.; Muratore, Kathryn E.

    2015-01-01

    The Department of Chemistry at American University has replaced its junior- and senior-level laboratory curriculum with two, two-semester long, student-led research projects as part of the department's American Chemical Society-accredited program. In the first semester of each sequence, a faculty instructor leads the students through a set of…

  8. Learning new words from storybooks: an efficacy study with at-risk kindergartners.

    Science.gov (United States)

    Justice, Laura M; Meier, Joanne; Walpole, Sharon

    2005-01-01

    The extant literature suggests that exposure to novel vocabulary words through repeated readings of storybooks influences children's word learning, and that adult elaboration of words in context can accelerate vocabulary growth. This study examined the influence of small-group storybook reading sessions on the acquisition of vocabulary words for at-risk kindergartners, and the impact of word elaboration on learning. An additional goal was to study differential responses to treatment for children with high versus low vocabulary skill. Using a pretest-posttest comparison group research design, 57 kindergartners were randomly assigned to a treatment (n = 29) or comparison (n = 28) group. Children were also differentiated into high (n = 31) versus low (n = 26) vocabulary skill groups using scores on a standardized receptive vocabulary test. Children in the treatment group completed 20 small-group storybook reading sessions during which they were exposed to 60 novel words randomly assigned to non-elaborated and elaborated conditions. Pre- and posttest examined the quality of children's definitions for the 60 novel words. Overall, word-learning gains were modest. Children in the treatment group made significantly greater gains in elaborated words relative to children in the comparison group; no influence of storybook reading exposure was seen for non-elaborated words. Children with low vocabulary scores made the greatest gains on elaborated words. Suggestions are offered for using storybooks as a clinical tool for fostering vocabulary development. As an efficacy study, results should inform future applied research on word learning for at-risk children.

  9. Measuring theory of mind in children. Psychometric properties of the ToM Storybooks.

    Science.gov (United States)

    Blijd-Hoogewys, E M A; van Geert, P L C; Serra, M; Minderaa, R B

    2008-11-01

    Although research on Theory-of-Mind (ToM) is often based on single task measurements, more comprehensive instruments result in a better understanding of ToM development. The ToM Storybooks is a new instrument measuring basic ToM-functioning and associated aspects. There are 34 tasks, tapping various emotions, beliefs, desires and mental-physical distinctions. Four studies on the validity and reliability of the test are presented, in typically developing children (n = 324, 3-12 years) and children with PDD-NOS (n = 30). The ToM Storybooks have good psychometric qualities. A component analysis reveals five components corresponding with the underlying theoretical constructs. The internal consistency, test-retest reliability, inter-rater reliability, construct validity and convergent validity are good. The ToM Storybooks can be used in research as well as in clinical settings.

  10. Measuring Theory of Mind in Children. Psychometric Properties of the ToM Storybooks

    NARCIS (Netherlands)

    Blijd-Hoogewys, E. M. A.; van Geert, P. L. C.; Serra, M.; Minderaa, R. B.

    2008-01-01

    Although research on Theory-of-Mind (ToM) is often based on single task measurements, more comprehensive instruments result in a better understanding of ToM development. The ToM Storybooks is a new instrument measuring basic ToM-functioning and associated aspects. There are 34 tasks, tapping various

  11. Facilitating Vocabulary Acquisition of Children with Cochlear Implants Using Electronic Storybooks

    Science.gov (United States)

    Messier, Jane; Wood, Carla

    2015-01-01

    The present intervention study explored the word learning of 18 children with cochlear implants in response to E-book instruction. Capitalizing on the multimedia options available in electronic storybooks, the intervention incorporated videos and definitions to provide a vocabulary intervention that includes evidence-based teaching strategies. The…

  12. Using electronic storybooks to support word learning in children with severe language impairments

    NARCIS (Netherlands)

    Smeets, Daisy J. H.; van Dijken, Marianne J.; Bus, Adriana G

    2012-01-01

    Novel word learning is reported to be problematic for children with severe language impairments (SLI). In this study, we tested electronic storybooks as a tool to support vocabulary acquisition in SLI children. In Experiment 1, 29 kindergarten SLI children heard four e-books each four times: (a) two

  13. A Joint Interactive Storybook Intervention Program for Preschool and Kindergarten Children

    Science.gov (United States)

    Vaknin-Nusbaum, Vered; Nevo, Einat

    2017-01-01

    The effectiveness of a joint interactive storybook reading program delivered by class teachers to develop literacy skills is examined in Hebrew-speaking preschool and kindergarten children. Post-intervention, both groups achieved significantly higher gains in language and print concept skills than age-matched comparison groups that did not have…

  14. Facilitating Storybook Interactions between Mothers and Their Preschoolers with Language Impairment.

    Science.gov (United States)

    Crowe, Linda K.; Norris, Janet A.; Hoffman, Paul R.

    2000-01-01

    Three children with language impairment (ages 38 to 41 months) and their mothers participated in a study evaluating a storybook reading process for facilitating mother-child interactions. The complete reading cycle (CRC) involved: (1) attentional vocative, (2) query, (3) response, and (4) feedback. Results indicated changes in mothers' storybook…

  15. Training Caregivers to Facilitate Communicative Participation of Preschool Children with Language Impairment during Storybook Reading

    Science.gov (United States)

    Crowe, Linda K.; Norris, Janet A.; Hoffman, Paul R.

    2004-01-01

    This study reports the effects of training six adult caregivers to use an interactive reading routine, termed Complete Reading Cycle (CRC), during storybook reading with their preschool children, aged 3;2 to 3;5, who exhibited language impairment. Caregivers were taught to be more responsive to their children's communicative attempts during…

  16. LED lamp

    Science.gov (United States)

    Galvez, Miguel; Grossman, Kenneth; Betts, David

    2013-11-12

    There is herein described a lamp for providing white light comprising a plurality of light sources positioned on a substrate. Each of said light sources comprises a blue light emitting diode (LED) and a dome that substantially covers said LED. A first portion of said blue light from said LEDs is transmitted through said domes and a second portion of said blue light is converted into a red light by a first phosphor contained in said domes. A cover is disposed over all of said light sources that transmits at least a portion of said red and blue light emitted by said light sources. The cover contains a second phosphor that emits a yellow light in response to said blue light. The red, blue and yellow light combining to form the white light and the white light having a color rendering index (CRI) of at least about 80.

  17. Joint storybook reading measured with children's book title checklist and the children's language development in early childhood

    Directory of Open Access Journals (Sweden)

    Katja Bajc

    2005-09-01

    Full Text Available In the present study we examined the relationship between parental educational level, joint storybook reading and children's language competence. Our sample included 123 5-year-old children attending one of the Slovenian preschools. Frequency of parent-child joint storybook reading was measured indirectly with the children's book title checklist, which was used in the Slovenian language environment for the first time, and which, in comparison with the parents' report about how often they read to their children, represents a more objective measure of storybook exposure. By using checklist we avoid socially desirable responses, which parents give because they think that reading is important for children's language development. We found out that parental education is positively related to the parental familiarity with the titles of books for children. Furthermore, the results show that storybook exposure is, regardless of parental educational level, a factor of home environment which makes an important contribution to the development of children's language competence.

  18. Reading Touch Screen Storybooks with Mothers Negatively Affects 7-Year-Old Readers’ Comprehension but Enriches Emotional Engagement

    OpenAIRE

    Ross, Kirsty M.; Pye, Rachel E.; Randell, Jordan

    2016-01-01

    Touch screen storybooks turn reading into an interactive multimedia experience, with hotspot-activated animations, sound effects, and games. Positive and negative effects of reading multimedia stories have been reported, but the underlying mechanisms which explain how children’s \\ud learning is affected remain uncertain. The present study examined the effect of storybook format(touch screen and print) on story comprehension, and considered how level of touch screen interactivity (high and low...

  19. Young children can be taught basic natural selection using a picture-storybook intervention.

    Science.gov (United States)

    Kelemen, Deborah; Emmons, Natalie A; Seston Schillaci, Rebecca; Ganea, Patricia A

    2014-04-01

    Adaptation by natural selection is a core mechanism of evolution. It is also one of the most widely misunderstood scientific processes. Misconceptions are rooted in cognitive biases found in preschoolers, yet concerns about complexity mean that adaptation by natural selection is generally not comprehensively taught until adolescence. This is long after untutored theoretical misunderstandings are likely to have become entrenched. In a novel approach, we explored 5- to 8-year-olds' capacities to learn a basic but theoretically coherent mechanistic explanation of adaptation through a custom storybook intervention. Experiment 1 showed that children understood the population-based logic of natural selection and also generalized it. Furthermore, learning endured 3 months later. Experiment 2 replicated these results and showed that children understood and applied an even more nuanced mechanistic causal explanation. The findings demonstrate that, contrary to conventional educational wisdom, basic natural selection is teachable in early childhood. Theory-driven interventions using picture storybooks with rich explanatory structure are beneficial.

  20. Local culture-based picture storybooks for teaching English for young learners

    Directory of Open Access Journals (Sweden)

    Ratminingsih Ni Made

    2018-01-01

    Full Text Available This paper reports the theoretical perspectives underlying the development of local culture-based picture storybooks for teaching English for young learners. It is a library research which derives from three main sources, journal articles, reference books, and internet articles. Local culture-based picture storybooks are kinds of printed materials which basically contain stories adapted from local culture stories accompanied with visualization in the forms of pictures telling the characters and the settings to help young learners easily understand the stories. They are developed considering the good criteria of storybooks [1, 2]. The benefits of its development are (1 to improve reading skill of young learners, (2 to build children English literacy through listening to the story read by the teachers and communicating interactively with them through dialogic reading, (3 create a fun learning atmosphere which enhances motivation and participation to take part in understanding and using the language, and (4 to preserve local culture. The books are developed using a combination of model [3, 4] which has 5 main steps namely need analysis, developing product, expert validation, and quality assessment by experts and users (teachers, and main product revision.

  1. Reading touch screen storybooks with mothers negatively affects seven-year-old readers’ comprehension but enriches emotional engagement

    Directory of Open Access Journals (Sweden)

    Kirsty Mhairi Ross

    2016-11-01

    Full Text Available Touch screen storybooks turn reading into an interactive multimedia experience, with hotspot-activated animations, sound effects, and games. Positive and negative effects of reading multimedia stories have been reported, but the underlying mechanisms which explain how children’s learning is affected remain uncertain. The present study examined the effect of storybook format (touch screen and print on story comprehension, and considered how level of touch screen interactivity (high and low and shared reading behaviors (cognitive and emotional scaffolding, emotional engagement might contribute to comprehension. Seven-year-olds (n = 22 were observed reading one touch screen storybook and one print storybook with their mothers. Story comprehension was inferior for the touch screen storybooks compared to the print versions. Touch screen interactivity had no significant effect on comprehension but did affect shared reading behaviors. The mother-child dyads spent less time talking about the story in the highly interactive touch screen condition, despite longer shared reading sessions because of touch screen interactions. Positive emotional engagement was greater for children and mothers in the highly interactive touch screen condition, due to additional positive emotions expressed during touch screen interactions. Negative emotional engagement was greater for children when reading and talking about the story in the highly interactive condition, and some mothers demonstrated negative emotional engagement with the touch screen activities. The less interactive touch screen storybook had little effect on shared reading behaviors, but mothers controlling behaviors were more frequent. Storybook format had no effect on the frequency of mothers’ cognitive scaffolding behaviors (comprehension questions, word help. Relationships between comprehension and shared reading behaviors were examined for each storybook, and length of the shared reading session and

  2. Reading Touch Screen Storybooks with Mothers Negatively Affects 7-Year-Old Readers’ Comprehension but Enriches Emotional Engagement

    Science.gov (United States)

    Ross, Kirsty M.; Pye, Rachel E.; Randell, Jordan

    2016-01-01

    Touch screen storybooks turn reading into an interactive multimedia experience, with hotspot-activated animations, sound effects, and games. Positive and negative effects of reading multimedia stories have been reported, but the underlying mechanisms which explain how children’s learning is affected remain uncertain. The present study examined the effect of storybook format (touch screen and print) on story comprehension, and considered how level of touch screen interactivity (high and low) and shared reading behaviors (cognitive and emotional scaffolding, emotional engagement) might contribute to comprehension. Seven-year-olds (n = 22) were observed reading one touch screen storybook and one print storybook with their mothers. Story comprehension was inferior for the touch screen storybooks compared to the print formats. Touch screen interactivity level had no significant effect on comprehension but did affect shared reading behaviors. The mother–child dyads spent less time talking about the story in the highly interactive touch screen condition, despite longer shared reading sessions because of touch screen interactions. Positive emotional engagement was greater for children and mothers in the highly interactive touch screen condition, due to additional positive emotions expressed during touch screen interactions. Negative emotional engagement was greater for children when reading and talking about the story in the highly interactive condition, and some mothers demonstrated negative emotional engagement with the touch screen activities. The less interactive touch screen storybook had little effect on shared reading behaviors, but mothers controlling behaviors were more frequent. Storybook format had no effect on the frequency of mothers’ cognitive scaffolding behaviors (comprehension questions, word help). Relationships between comprehension and shared reading behaviors were examined for each storybook, and although length of the shared reading session and

  3. Clinical impact of wordless picture storybooks on bilingual narrative language production: A comparison of the 'Frog' stories.

    Science.gov (United States)

    Heilmann, John J; Rojas, Raúl; Iglesias, Aquiles; Miller, Jon F

    2016-05-01

    Language sampling, recognized as a gold standard for expressive language assessment, is often elicited using wordless picture storybooks. A series of wordless storybooks, commonly referred to as 'Frog' stories, have been frequently used in language-based research with children from around the globe. To examine the impact that differences in stories have on narrative output by comparing narrative productions across a series of five storybooks produced by 831 bilingual (Spanish-English) children in kindergarten through third grade. Each participant produced oral narratives using one of the five Frog storybooks in both English and Spanish. The narratives were recorded, transcribed and coded for a variety of measures of language production. Negligible differences were observed in language measures when comparing groups of children who told different stories, with the exception of lexical diversity. The implications of using different storybooks to elicit narrative language samples from children are discussed from the perspectives of research and clinical practice. © 2015 Royal College of Speech and Language Therapists.

  4. Goniometric characterization of LED based greenhouse lighting

    DEFF Research Database (Denmark)

    Thorseth, Anders; Lindén, Johannes; Corell, Dennis Dan

    2015-01-01

    This paper describes a demonstration of goniospectroradiometry for characterizations of new light emitting diode (LED) based luminaries for enhanced photosynthesis in greenhouses. It highlights the differences between measurement of the traditional high pressure sodium (HPS) luminaries and the LED...

  5. Goniometric characterization of LED based greenhouse lighting

    DEFF Research Database (Denmark)

    Thorseth, Anders; Lindén, Johannes; Corell, Dennis Dan

    2015-01-01

    This paper describes a demonstration of goniospectroradiometry for characterizations of new light emitting diode (LED) based luminaries for enhanced photosynthesis in greenhouses. It highlights the differences between measurement of the traditional high pressure sodium (HPS) luminaries and the LED...... based luminaries. The LED based luminaries are compared to traditional HPS luminaries; in terms of energy efficiency with regard to the photosynthetic photon flux, and the LED luminaries were found to be more effective than the HPS luminaries...

  6. Personalisation: A theoretical possibility to reinvigorate children's interest in storybook reading and facilitate greater book diversity

    OpenAIRE

    Kucirkova, N.

    2016-01-01

    Since the early 2010s, there has been a proliferation of new platforms for children’s stories (e.g. storybook apps or iBooks), but not necessarily greater diversity of story content or children’s greater interest in reading. This article argues for a new approach to address the apparent paradox of a wider availability of children’s literature combined with children’s eroded reading interest. The issue is suggested to be addressed by considering the agency and aesthetic dimensions which lie at...

  7. Effects of a Cross-Linguistic Storybook Intervention on the Second Language Development of Two Preschool English Language Learners

    Science.gov (United States)

    Huennekens, Mary Ellen; Xu, Yaoying

    2010-01-01

    The purpose of this study was to examine the effects of a shared reading experience between parent and child in the child's home language on the emergent literacy and language acquisition in English of preschool-age English Language Learners. Parents of Spanish-speaking four-year-old Head Start students read storybooks in Spanish with their…

  8. "Este Libro Es Mi Historia": Mother-Child Interactions during Storybook Reading in a Mexican-American Household.

    Science.gov (United States)

    Manyak, Patrick

    A study explored the storybook reading experiences between Ms. Garza and her children. A broad conception of the zone of proximal development, involving use, adaptation, and transformation of culturally shaped tools in the process of shared activity, provides the framework for examining this particular Mexican-American family's reading behavior.…

  9. Accelerating Preschoolers' Early Literacy Development through Classroom-Based Teacher-Child Storybook Reading and Explicit Print Referencing

    Science.gov (United States)

    Justice, Laura M.; Kaderavek, Joan N.; Fan, Xitao; Sofka, Amy; Hunt, Aileen

    2009-01-01

    Purpose: This study examined the impact of teacher use of a print referencing style during classroom-based storybook reading sessions conducted over an academic year. Impacts on preschoolers' early literacy development were examined, focusing specifically on the domain of print knowledge. Method: This randomized, controlled trial examined the…

  10. Using electronic storybooks to support word learning in children with severe language impairments.

    Science.gov (United States)

    Smeets, Daisy J H; van Dijken, Marianne J; Bus, Adriana G

    2014-01-01

    Novel word learning is reported to be problematic for children with severe language impairments (SLI). In this study, we tested electronic storybooks as a tool to support vocabulary acquisition in SLI children. In Experiment 1, 29 kindergarten SLI children heard four e-books each four times: (a) two stories were presented as video books with motion pictures, music, and sounds, and (b) two stories included only static illustrations without music or sounds. Two other stories served as the control condition. Both static and video books were effective in increasing knowledge of unknown words, but static books were most effective. Experiment 2 was designed to examine which elements in video books interfere with word learning: video images or music or sounds. A total of 23 kindergarten SLI children heard 8 storybooks each four times: (a) two static stories without music or sounds, (b) two static stories with music or sounds, (c) two video stories without music or sounds, and (d) two video books with music or sounds. Video images and static illustrations were equally effective, but the presence of music or sounds moderated word learning. In children with severe SLI, background music interfered with learning. Problems with speech perception in noisy conditions may be an underlying factor of SLI and should be considered in selecting teaching aids and learning environments. © Hammill Institute on Disabilities 2012.

  11. THE EFFECTIVENESS OF USING PHONICS INSTRUCTION AND STORYBOOKS IN ENGLISH READING CLASSES TO IMPROVE STUDENT PARTICIPATION

    Directory of Open Access Journals (Sweden)

    Naning Tri Wahyuni

    2016-08-01

    Full Text Available The purpose of this study is to examine the effectiveness of instructional methods based on phonics instruction in reading classes to improve students participation therefore they can develop to their maximum potential. Using qualitative tools of observation, documentation and interview, this research was focusing the inquiry on investigating students’ reception to the phonics instruction model, observing their participation in the classroom activities, also investigating instructional methods which attract students to more actively contribute in learning activities. The finding shows that the reception of students to the model was good and they showed much eagerness in following the program. Further investigation revealed that students keen to participate more in the classroom activities especially in certain activities with the use of sound sheets, sound book, flash card sheets, word box sheets, songs, games and storybooks. However, there were two challenges identified during 16 weeks running the study; the lack of teachers’ skill in delivering this method efficiently also the limited collection of English story books in school. Hence, to improve the effectiveness of the use of phonics instruction in reading classroom, firstly, training for teachers would be needed to deliver the method effectively, secondly, considering the fact that school still have limited collection of English story books or any English books, the collaboration with government agencies or other promising bodies could be done to help in providing more collection of storybooks in school.

  12. LED-roulette : LED's vervangen balletje

    NARCIS (Netherlands)

    Goossens, P.

    2007-01-01

    Iedereen waagt wel eens een gokje, in een loterij of misschien ook in een casino. Wie droomt er immers niet van om op een gemakkelijke manier rijk te worden? Met de hier beschreven LED-roulette valt weliswaar weinig te winnen, maar het is wel een uitstekende manier om het roulettespel thuis te

  13. Facilitating Vocabulary Acquisition of Children With Cochlear Implants Using Electronic Storybooks.

    Science.gov (United States)

    Messier, Jane; Wood, Carla

    2015-10-01

    The present intervention study explored the word learning of 18 children with cochlear implants in response to E-book instruction. Capitalizing on the multimedia options available in electronic storybooks, the intervention incorporated videos and definitions to provide a vocabulary intervention that includes evidence-based teaching strategies. The extent of the children's word learning was assessed using three assessment tasks: receptive pointing, expressively labeling, and word defining. Children demonstrated greater immediate expressive labeling gains and definition generation gains for words taught in the treatment condition compared to those in the comparison condition. In addition, the children's performance on delayed posttest vocabulary assessments indicated better retention across the expressive vocabulary task for words taught within the treatment condition as compared to the comparison condition. Findings suggest that children with cochlear implants with functional speech perception can benefit from an oral-only multimedia-enhanced intensive vocabulary instruction. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  14. Promoting language and social communication development in babies through an early storybook reading intervention.

    Science.gov (United States)

    Brown, Michelle I; Westerveld, Marleen F; Trembath, David; Gillon, Gail T

    2017-12-15

    This study examined the effectiveness of low- and high-intensity early storybook reading (ESR) intervention workshops delivered to parents for promoting their babies language and social communication development. These workshops educated parents on how to provide a stimulating home reading environment and engage in parent-child interactions during ESR. Parent-child dyads (n = 32); child age: 3-12 months, were assigned into two intervention conditions: low and high intensity (LI versus HI) groups. Both groups received the same ESR strategies; however, the HI group received additional intervention time, demonstrations and support. Outcome measures were assessed pre-intervention, one and three months post-intervention and when the child turned 2 years of age. A significant time-group interaction with increased performance in the HI group was observed for language scores immediately post-intervention (p = 0.007) and at 2-years-of-age (p = 0.022). Significantly higher broader social communication scores were associated with the HI group at each of the time points (p = 0.018, p = 0.001 and p = 0.021, respectively). Simple main effect revealed that both groups demonstrated a significant improvement in language, broader social communication and home reading practices scores. ESR intervention workshops may promote language and broader social communication skills. The HI ESR intervention workshop was associated with significantly higher language and broader social communication scores.

  15. Broadband Radiometric LED Measurements.

    Science.gov (United States)

    Eppeldauer, G P; Cooksey, C C; Yoon, H W; Hanssen, L M; Podobedov, V B; Vest, R E; Arp, U; Miller, C C

    2016-01-01

    At present, broadband radiometric measurements of LEDs with uniform and low-uncertainty results are not available. Currently, either complicated and expensive spectral radiometric measurements or broadband photometric LED measurements are used. The broadband photometric measurements are based on the CIE standardized V(λ) function, which cannot be used in the UV range and leads to large errors when blue or red LEDs are measured in its wings, where the realization is always poor. Reference irradiance meters with spectrally constant response and high-intensity LED irradiance sources were developed here to implement the previously suggested broadband radiometric LED measurement procedure [1, 2]. Using a detector with spectrally constant response, the broadband radiometric quantities of any LEDs or LED groups can be simply measured with low uncertainty without using any source standard. The spectral flatness of filtered-Si detectors and low-noise pyroelectric radiometers are compared. Examples are given for integrated irradiance measurement of UV and blue LED sources using the here introduced reference (standard) pyroelectric irradiance meters. For validation, the broadband measured integrated irradiance of several LED-365 sources were compared with the spectrally determined integrated irradiance derived from an FEL spectral irradiance lamp-standard. Integrated responsivity transfer from the reference irradiance meter to transfer standard and field UV irradiance meters is discussed.

  16. Benefits of Motion in Animated Storybooks for Children's Visual Attention and Story Comprehension. An Eye-Tracking Study.

    Science.gov (United States)

    Takacs, Zsofia K; Bus, Adriana G

    2016-01-01

    The present study provides experimental evidence regarding 4-6-year-old children's visual processing of animated versus static illustrations in storybooks. Thirty nine participants listened to an animated and a static book, both three times, while eye movements were registered with an eye-tracker. Outcomes corroborate the hypothesis that specifically motion is what attracts children's attention while looking at illustrations. It is proposed that animated illustrations that are well matched to the text of the story guide children to those parts of the illustration that are important for understanding the story. This may explain why animated books resulted in better comprehension than static books.

  17. Dansk LED - Museumsbelysning

    DEFF Research Database (Denmark)

    Poulsen, Peter Behrensdorff; Dam-Hansen, Carsten; Thorseth, Anders

    Projektet har til formål at anvende dansk forskning inden for optik og lys til at realisere innovative energieffektive LED lyssystemer til museumsbranchen.......Projektet har til formål at anvende dansk forskning inden for optik og lys til at realisere innovative energieffektive LED lyssystemer til museumsbranchen....

  18. IRA Outstanding Dissertation Award for 1998: The Construction of Literary Understanding by First and Second Graders in Response to Picture Storybook Read-Alouds.

    Science.gov (United States)

    Sipe, Lawrence R.

    1998-01-01

    Summarizes a descriptive naturalistic study of the literary competence of a class of first and second graders as suggested by their responses during read-alouds of picture books. Finds that the children were sophisticated literary critics, and the storybook read-aloud situation was an important site for the development of their literary…

  19. A Psychometric Evaluation of the Danish Version of the Theory of Mind Storybook for 8-14 Year-Old Children

    DEFF Research Database (Denmark)

    Clemmensen, Lars; Bartels-Velthuis, Agna A.; Jespersen, Rókur av F.

    2016-01-01

    properties of the Danish version of the Theory-of-Mind Storybook Frederik (ToM-Frederik). METHODS: We assessed whether ToM-Frederik scores differed between a group of 41 typically developing (TD) children and a group of 33 children with High Functioning Autism Spectrum Disorder (HFASD). A lower mean To...

  20. Systematic Replication of the Effects of a Supplementary, Technology-Assisted, Storybook Intervention for Preschool Children with Weak Vocabulary and Comprehension Skills

    Science.gov (United States)

    Greenwood, Charles R.; Carta, Judith J.; Kelley, Elizabeth S.; Guerrero, Gabriela; Kong, Na Young; Atwater, Jane; Goldstein, Howard

    2016-01-01

    In 2013, Spencer, Goldstein, Sherman, et al. reported the promising effects of a supplemental, technology-assisted, storybook intervention (Tier 2) containing embedded instruction targeting the oral language learning of preschool children at risk for delays. We sought to advance knowledge of the intervention by replicating it in a new sample and…

  1. Parent Education for Dialogic Reading during Shared Storybook Reading: Multiple Case Study of Online and Face-to-Face Delivery Models

    Science.gov (United States)

    Beschorner, Beth

    2013-01-01

    This study examined the impact of a parent education program on the frequency of shared storybook reading and dialogic reading techniques. Additionally, the contextual factors that influenced the outcomes of the program were explored. Seventeen parents completed a nine-week face-to-face parent education program and fifteen parents completed a…

  2. Large area LED package

    Science.gov (United States)

    Goullon, L.; Jordan, R.; Braun, T.; Bauer, J.; Becker, F.; Hutter, M.; Schneider-Ramelow, M.; Lang, K.-D.

    2015-03-01

    Solid state lighting using LED-dies is a rapidly growing market. LED-dies with the needed increasing luminous flux per chip area produce a lot of heat. Therefore an appropriate thermal management is required for general lighting with LEDdies. One way to avoid overheating and shorter lifetime is the use of many small LED-dies on a large area heat sink (down to 70 μm edge length), so that heat can spread into a large area while at the same time light also appears on a larger area. The handling with such small LED-dies is very difficult because they are too small to be picked with common equipment. Therefore a new concept called collective transfer bonding using a temporary carrier chip was developed. A further benefit of this new technology is the high precision assembly as well as the plane parallel assembly of the LED-dies which is necessary for wire bonding. It has been shown that hundred functional LED-dies were transferred and soldered at the same time. After the assembly a cost effective established PCB-technology was applied to produce a large-area light source consisting of many small LED-dies and electrically connected on a PCB-substrate. The top contacts of the LED-dies were realized by laminating an adhesive copper sheet followed by LDI structuring as known from PCB-via-technology. This assembly can be completed by adding converting and light forming optical elements. In summary two technologies based on standard SMD and PCB technology have been developed for panel level LED packaging up to 610x 457 mm2 area size.

  3. LED roadway luminaires evaluation.

    Science.gov (United States)

    2012-02-01

    This research explores whether LED roadway luminaire technologies are a viable future solution to providing roadway lighting. Roadway lighting : enhances highway safety and traffic flow during limited lighting conditions. The purpose of this evaluati...

  4. Factorial structure of the 'ToM Storybooks': A test evaluating multiple components of Theory of Mind.

    Science.gov (United States)

    Bulgarelli, Daniela; Testa, Silvia; Molina, Paola

    2015-06-01

    This study examined the factorial structure of the Theory of Mind (ToM) Storybooks, a comprehensive 93-item instrument tapping the five components in Wellman's model of ToM (emotion recognition, understanding of desire and beliefs, ability to distinguish between physical and mental entities, and awareness of the link between perception and knowledge). A sample of 681 three- to eight-year-old Italian children was divided into three age groups to assess whether factorial structure varied across different age ranges. Partial credit model analysis was applied to the data, leading to the empirical identification of 23 composite variables aggregating the ToM Storybooks items. Confirmatory factor analysis was then conducted on the composite variables, providing support for the theoretical model. There were partial differences in the specific composite variables making up the dimensions for each of the three age groups. A single test evaluating distinct dimensions of ToM is a valuable resource for clinical practice which may be used to define differential profiles for specific populations. © 2014 The British Psychological Society.

  5. Literacy skills in children with cochlear implants: the importance of early oral language and joint storybook reading.

    Science.gov (United States)

    DesJardin, Jean L; Ambrose, Sophie E; Eisenberg, Laurie S

    2009-01-01

    The goal of this study was to longitudinally examine relationships between early factors (child and mother) that may influence children's phonological awareness and reading skills 3 years later in a group of young children with cochlear implants (N = 16). Mothers and children were videotaped during two storybook interactions, and children's oral language skills were assessed using the "Reynell Developmental Language Scales, third edition." Three years later, phonological awareness, reading skills, and language skills were assessed using the "Phonological Awareness Test," the "Woodcock-Johnson-III Diagnostic Reading Battery," and the "Oral Written Language Scales." Variables included in the data analyses were child (age, age at implant, and language skills) and mother factors (facilitative language techniques) and children's phonological awareness and reading standard scores. Results indicate that children's early expressive oral language skills and mothers' use of a higher level facilitative language technique (open-ended question) during storybook reading, although related, each contributed uniquely to children's literacy skills. Individual analyses revealed that the children with expressive standard scores below 70 at Time 1 also performed below average (reading tasks 3 years later. Guidelines for professionals are provided to support literacy skills in young children with cochlear implants.

  6. Surface plasmon enhanced LED

    OpenAIRE

    Vučković, Jelena; Lončar, Marko; Painter, Oskar; Scherer, Axel

    2000-01-01

    Summary form only given. We designed and fabricated an LED based on a thin semiconductor membrane (λ/2) with silver mirrors. A large spontaneous emission enhancement and a high modulation speed are obtainable due to the strong localization of the electromagnetic field in the microcavity. The coupling to surface plasmon modes which are subsequently scattered out by means of a grating is used to improve the extraction efficiency of the LED. The bottom mirror is thick and unpatterned. The top mi...

  7. Light Emitting Diode (LED)

    Science.gov (United States)

    1997-01-01

    A special lighting technology was developed for space-based commercial plant growth research on NASA's Space Shuttle. Surgeons have used this technology to treat brain cancer on Earth, in two successful operations. The treatment technique called photodynamic therapy, requires the surgeon to use tiny pinhead-size Light Emitting Diodes (LEDs) (a source releasing long wavelengths of light) to activate light-sensitive, tumor-treating drugs. Laser light has been used for this type of surgery in the past, but the LED light illuminates through all nearby tissues, reaching parts of a tumor that shorter wavelengths of laser light carnot. The new probe is safer because the longer wavelengths of light are cooler than the shorter wavelengths of laser light, making the LED less likely to injure normal brain tissue near the tumor. It can also be used for hours at a time while still remaining cool to the touch. The LED probe consists of 144 tiny pinhead-size diodes, is 9-inches long, and about one-half-inch in diameter. The small balloon aids in even distribution of the light source. The LED light source is compact, about the size of a briefcase, and can be purchased for a fraction of the cost of a laser. The probe was developed for photodynamic cancer therapy by the Marshall Space Flight Center under a NASA Small Business Innovative Research program grant.

  8. Light Emitting Diodes (LEDs)

    Science.gov (United States)

    1997-01-01

    A special lighting technology was developed for space-based commercial plant growth research on NASA's Space Shuttle. Surgeons have used this technology to treat brain cancer on Earth, in two successful operations. The treatment technique, called Photodynamic Therapy, requires the surgeon to use tiny, pinhead-size Light Emitting Diodes (LEDs) (a source that releases long wavelengths of light ) to activate light-sensitive, tumor-treating drugs. 'A young woman operated on in May 1999 has fully recovered with no complications and no evidence of the tumor coming back,' said Dr. Harry Whelan, a pediatric neurologist at the Medical Hospital of Wisconsin in Milwaukee. Laser light has been used for this type of surgery in the past, but the LED light illuminates through all nearby tissues, reaching parts of a tumor that shorter wavelengths of laser light carnot. The new probe is safer because the longer wavelengths of light are cooler than the shorter wavelengths of laser light, making the LED less likely to injure normal brain tissue near the tumor. It can be used for hours at a time while still remaining cool to the touch. The LED light source is compact, about the size of a briefcase, and can be purchased for a fraction of the cost of a laser. The LEDs, developed and managed by NASA's Marshall Space Flight Center, have been used on seven Space Shuttle flights inside the Microgravity Astroculture Facility. This technology has also been successfully used to further commercial research in crop growth.

  9. Led-sukellusvalaisin

    OpenAIRE

    Saarelainen, Mikko

    2012-01-01

    Opinnäytetyön aiheena on LED ja sen käyttö sukellusvalaisimissa. Työn tarkoitus oli tutkia miten LED toimii ja miten se soveltuu käytettäväksi sukellusvalaisimessa, sekä syventää omaa tietoutta valosta, mitä se on ja miten sitä mitataan. Työssä käydään läpi LEDin ominaisuuksia ja miten se eroaa muista sukellusvalaisimissa käytetyistä lampuista. Työ on toteutettu tutustumalla LEDiin ja valoon käyttämällä erilaisia lähteitä ja päivittämällä nykyinen sukellusvalaisimeni LED-sukellusvalaisime...

  10. [LED lights in dermatology].

    Science.gov (United States)

    Noé, C; Pelletier-Aouizerate, M; Cartier, H

    2017-04-01

    The use in dermatology of light-emitting diodes (LEDs) continues to be surrounded by controversy. This is due mainly to poor knowledge of the physicochemical phases of a wide range of devices that are difficult to compare to one another, and also to divergences between irrefutable published evidence either at the level of in vitro studies or at the cellular level, and discordant clinical results in a variety of different indications: rejuvenation, acne, wound healing, leg ulcers, and cutaneous inflammatory or autoimmune processes. Therapeutic LEDs can emit wavelengths ranging from the ultraviolet, through visible light, to the near infrared (247-1300 nm), but only certain bands have so far demonstrated any real value. We feel certain that if this article remains factual, then readers will have a different, or at least more nuanced, opinion concerning the use of such LED devices in dermatology. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  11. Photobiocatalytic alcohol oxidation using LED light sources

    NARCIS (Netherlands)

    Rauch, M.C.R.; Schmidt, S.; Arends, I.W.C.E.; oppelt, K.; Kara, S; Hollmann, F.

    2016-01-01

    The photocatalytic oxidation of NADH using a flavin photocatalyst and a simple blue LED light source is reported. This in situ NAD+ regeneration system can be used to promote biocatalytic, enantioselective oxidation reactions. Compared to the traditional use of white light bulbs this method enables

  12. Structured Instruction With Modified Storybooks to Teach Morphosyntax and Vocabulary to Preschoolers Who are Deaf/Hard of Hearing.

    Science.gov (United States)

    Richels, Corrin G; Schwartz, Kathryn S; Bobzien, Jonna L; Raver, Sharon A

    2016-10-01

    Children who are deaf/hard of hearing (D/HH) are at risk for diminished morphosyntactical and vocabulary development. The purpose of this study was to examine the effects of repeated reading combined with structured instruction. Targets were a morphosyntactical form and novel vocabulary words. Participants were 3 preschoolers who are D/HH who were receiving instruction with an oral approach. Data from a multiple baseline design indicated that all children acquired the targeted skills and demonstrated high levels of generalization of these skills to untrained context. Implications for teaching young children who are D/HH using repeated storybook reading are discussed. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  13. Thermal management for LED applications

    CERN Document Server

    Poppe, András

    2014-01-01

    Thermal Management for LED Applications provides state-of-the-art information on recent developments in thermal management as it relates to LEDs and LED-based systems and their applications. Coverage begins with an overview of the basics of thermal management including thermal design for LEDs, thermal characterization and testing of LEDs, and issues related to failure mechanisms and reliability and performance in harsh environments. Advances and recent developments in thermal management round out the book with discussions on advances in TIMs (thermal interface materials) for LED applications, advances in forced convection cooling of LEDs, and advances in heat sinks for LED assemblies. This book also: Presents a comprehensive overview of the basics of thermal management as it relates to LEDs and LED-based systems Discusses both design and thermal management considerations when manufacturing LEDs and LED-based systems Covers reliability and performance of LEDs in harsh environments Has a hands-on applications a...

  14. Deslumbramiento en dispositivos led

    OpenAIRE

    Ixtaina, Rubén Pablo; Presso, Matías; Ferreyra, Joaquín

    2012-01-01

    En el presente trabajo se presenta un estudio realizado en el LAL a dispositivos para señalización (semáforos, balizas, barrales lumínicos) con tecnología led. Las mediciones tradicionales de intensidad luminosa se complementaron con el análisis de la luminancia de los dispositivos, evaluada para diversas aperturas angula-res. Los resultados obtenidos marcan un notorio incre-mento en las luminancias puntuales, para valores de emisión globales comparables a los obtenidos en dispo-sitivos conve...

  15. Following Tradition

    OpenAIRE

    Bronner, Simon J.

    1998-01-01

    Following Tradition is an expansive examination of the history of tradition—"one of the most common as well as most contested terms in English language usage"—in Americans' thinking and discourse about culture. Tradition in use becomes problematic because of "its multiple meanings and its conceptual softness." As a term and a concept, it has been important in the development of all scholarly fields that study American culture. Folklore, history, American studies, anthropology, cultural studie...

  16. The Lifetime Prediction of LED Drivers and Lamps

    NARCIS (Netherlands)

    Sun, B.

    2017-01-01

    Light-Emitting Diodes (LEDs) have become a very promising alternative lighting source with the main advantages of a longer lifetime and a higher efficiency than traditional ones. However, the LED lamp’s lifetime is compromised by its driver’s reliability. Although extensive studies have been made on

  17. Development of an intelligent integrated LED system-in-package

    NARCIS (Netherlands)

    Gielen, A.W.J.; Hesen, P.; Swartjes, F.H.M.; Zeijl, H. van; Boschman, F.; Bullema, J.-E.; Werkhoven, R.J.; Koh, S.

    2011-01-01

    Intelligent LED lighting systems can save up to 80% of energy compared to traditional lighting systems. In order to provide these intelligent lighting products at reaseonable costs, integration and miniaturisation are important steps. To this end we have designed a LED system-in-package that

  18. Traditional Chinese Biotechnology

    Science.gov (United States)

    Xu, Yan; Wang, Dong; Fan, Wen Lai; Mu, Xiao Qing; Chen, Jian

    The earliest industrial biotechnology originated in ancient China and developed into a vibrant industry in traditional Chinese liquor, rice wine, soy sauce, and vinegar. It is now a significant component of the Chinese economy valued annually at about 150 billion RMB. Although the production methods had existed and remained basically unchanged for centuries, modern developments in biotechnology and related fields in the last decades have greatly impacted on these industries and led to numerous technological innovations. In this chapter, the main biochemical processes and related technological innovations in traditional Chinese biotechnology are illustrated with recent advances in functional microbiology, microbial ecology, solid-state fermentation, enzymology, chemistry of impact flavor compounds, and improvements made to relevant traditional industrial facilities. Recent biotechnological advances in making Chinese liquor, rice wine, soy sauce, and vinegar are reviewed.

  19. Traditional Medicine in Developing Countries

    DEFF Research Database (Denmark)

    Thorsen, Rikke Stamp

    People use traditional medicine to meet their health care needs in developing countries and medical pluralism persists worldwide despite increased access to allopathic medicine. Traditional medicine includes a variety of treatment opportunities, among others, consultation with a traditional healer...... or spiritual healer and self-treatment with herbal medicine or medicinal plants. Reliance on traditional medicine varies between countries and rural and urban areas, but is reported to be as high as 80% in some developing countries. Increased realization of the continued importance of traditional medicine has...... led to the formulation of policies on the integration of traditional medicine into public health care. Local level integration is already taking place as people use multiple treatments when experiencing illness. Research on local level use of traditional medicine for health care, in particular the use...

  20. LED driver for stroboscopic interferometry

    Science.gov (United States)

    Paulin, T.; Heikkinen, V.; Kassamakov, I.; Hæggström, E.

    2012-04-01

    Three different types of white light emitting diodes (LEDs) and three types of single color LEDs were tested as light sources for stroboscopic scanning white light interferometry (SSWLI) for dynamic (MEMS) characterization. Short, intense, light pulses and low duty cycle (DC-10 MHz), and can drive single LEDs at 5A peak current (0.7% duty cycle at 1 MHz). The shortest measured electrical pulses were 6.2 +/- 0.1 ns FDHM. The minimum measured Full Duration at Half Maximum (FDHM) of the optical pulse was 8.4 +/- 0.1 ns using nonphosphor white LED and 32.1 +/- 0.1 ns using white phosphor-converted LED (0.7 % duty cycle at 1 MHz in both cases). The minimum optical pulse FDHM for a single color blue/green LED was 6.4 +/- 0.1 ns. The maximum intensity of these pulses was 630 +/- 40 μW and 540 +/- 30 μW, respectively. All types of white LEDs could be used for stroboscopic SWLI measurements at frequencies up to 2 MHz. For higher frequencies, non-phosphor white LEDs must be used together with a cyan LED to avoid ringing in the SWLI interferogram.

  1. Nobel Prize for blue LEDs

    International Nuclear Information System (INIS)

    Kraftmakher, Yaakov

    2015-01-01

    A brief review of lighting technologies is presented. Unavoidable restrictions for incandescent light bulbs caused by the Planck distribution and properties of the human eye are illustrated. The efficiency and luminous efficacy of thermal radiation are calculated for various temperatures; the results clearly show the limitations for thermal radiators. The only way to overcome these limitations is using non-thermal radiators, such as fluorescent lamps and light-emitting diodes (LEDs). Unique advantages of LEDs undoubtedly made a revolution in this field. A crucial element of this progress is the blue LEDs (Nobel Prize 2014). Some experiments with a blue and a green LED are described: (i) the luminescence triggered in a green-yellow phosphor inside a white LED by the blue LED; (ii) radiant spectra and ‘efficiency droop’ in the LEDs; (iii) modulation of the blue LED up to 4 MHz; and (iv) the h/e ratio from the turn-on voltage of the green LED. The experiments are suitable for undergraduate laboratories and usable as classroom demonstrations. (paper)

  2. Nobel Prize for blue LEDs

    Science.gov (United States)

    Kraftmakher, Yaakov

    2015-05-01

    A brief review of lighting technologies is presented. Unavoidable restrictions for incandescent light bulbs caused by the Planck distribution and properties of the human eye are illustrated. The efficiency and luminous efficacy of thermal radiation are calculated for various temperatures; the results clearly show the limitations for thermal radiators. The only way to overcome these limitations is using non-thermal radiators, such as fluorescent lamps and light-emitting diodes (LEDs). Unique advantages of LEDs undoubtedly made a revolution in this field. A crucial element of this progress is the blue LEDs (Nobel Prize 2014). Some experiments with a blue and a green LED are described: (i) the luminescence triggered in a green-yellow phosphor inside a white LED by the blue LED; (ii) radiant spectra and ‘efficiency droop’ in the LEDs; (iii) modulation of the blue LED up to 4 MHz; and (iv) the h/e ratio from the turn-on voltage of the green LED. The experiments are suitable for undergraduate laboratories and usable as classroom demonstrations.

  3. Understanding Interactive CD-ROM Storybooks and Their Functions in Reading Comprehension: A Critical Review

    Science.gov (United States)

    Ertem, Ihsan Seyit

    2011-01-01

    With dramatic changes and recent advances in multimedia, digital technologies through computers propose new ways for introducing kids to the literacy. Literacy educators have stated that traditional printed books are not sufficient and electronic books have the potential to change reading skills. As a valuable tool in educational settings new and…

  4. New dental applications with LEDs

    DEFF Research Database (Denmark)

    Argyraki, A.; Ou, Yiyu; Petersen, Paul Michael

    Visible and ultraviolet LEDs will in the future give rise to new dental applications. Fluorescence imaging, photodynamic therapy and photoactivated disinfection are important future candidates for diagnostics and treatment in dentistry.......Visible and ultraviolet LEDs will in the future give rise to new dental applications. Fluorescence imaging, photodynamic therapy and photoactivated disinfection are important future candidates for diagnostics and treatment in dentistry....

  5. Silicone materials for LED packaging

    Science.gov (United States)

    Bahadur, Maneesh; Norris, Ann W.; Zarisfi, Afrooz; Alger, James S.; Windiate, Christopher C.

    2006-08-01

    Silicone based materials have attracted considerable attention from light emitting diode (LED) manufacturers for use as encapsulants and lenses for many high brightness LED (HB LED) devices. Currently silicones function in two key roles in HB LED devices, (1) as protective lenses and (2) stress relieving encapsulants for wire bond protection. The key attributes of silicones that make them attractive as light path materials for high brightness HB LEDs include their high transparency in the UV-visible region, controlled refractive index (RI), stable thermo-mechanical properties, and tuneable modulus from soft gels to hard resins. This paper will describe recent developments in moldable silicone hard resin materials. Progress on cavity moldable and liquid injection moldable (LIM) silicone compositions for discreet components is described. Also, an example of liquid injection overmolding is presented.

  6. Light pipes for LED measurements

    Science.gov (United States)

    Floyd, S. R.; Thomas, E. F., Jr.

    1976-01-01

    Light pipe directly couples LED optical output to single detector. Small area detector measures total optical output of diode. Technique eliminates thermal measurement problems and channels optical output to remote detector.

  7. Practical lighting design with LEDs

    CERN Document Server

    Lenk, Ron

    2016-01-01

    The second edition of Practical Lighting Design with LEDs has been revised and updated to provide the most current information for developing light-emitting diodes products. The authors, noted authorities in the field, offer a review of the most relevant topics including optical performance, materials, thermal design, and modeling and measurement. Comprehensive in scope, the text covers all the information needed to design LEDs into end products.

  8. University of Nevada Las Vegas LED Display Engineering

    Energy Technology Data Exchange (ETDEWEB)

    None

    2010-08-31

    The primary objective of this part of the project is to develop and implement a method that compensates for the inefficiency of the green LED. The proposed engineering solution which will be the backbone of this project will be to use RGBW combination in every pixel to save energy. Two different RGBW geometrical pixel configurations will be implemented and compared against traditional LED configurations. These configurations will be analyzed for energy efficiency while keeping the quality of the display the same. Cost of the addition of white LEDs to displays along with energy cost savings will be presented and analyzed.

  9. Visual color matching system based on RGB LED light source

    Science.gov (United States)

    Sun, Lei; Huang, Qingmei; Feng, Chen; Li, Wei; Wang, Chaofeng

    2018-01-01

    In order to study the property and performance of LED as RGB primary color light sources on color mixture in visual psychophysical experiments, and to find out the difference between LED light source and traditional light source, a visual color matching experiment system based on LED light sources as RGB primary colors has been built. By simulating traditional experiment of metameric color matching in CIE 1931 RGB color system, it can be used for visual color matching experiments to obtain a set of the spectral tristimulus values which we often call color-matching functions (CMFs). This system consists of three parts: a monochromatic light part using blazed grating, a light mixing part where the summation of 3 LED illuminations are to be visually matched with a monochromatic illumination, and a visual observation part. The three narrow band LEDs used have dominant wavelengths of 640 nm (red), 522 nm (green) and 458 nm (blue) respectively and their intensities can be controlled independently. After the calibration of wavelength and luminance of LED sources with a spectrophotometer, a series of visual color matching experiments have been carried out by 5 observers. The results are compared with those from CIE 1931 RGB color system, and have been used to compute an average locus for the spectral colors in the color triangle, with white at the center. It has been shown that the use of LED is feasible and has the advantages of easy control, good stability and low cost.

  10. Semiconductor lasers and herterojunction leds

    CERN Document Server

    Kressel, Henry

    2012-01-01

    Semiconductor Lasers and Heterojunction LEDs presents an introduction to the subject of semiconductor lasers and heterojunction LEDs. The book reviews relevant basic solid-state and electromagnetic principles; the relevant concepts in solid state physics; and the p-n junctions and heterojunctions. The text also describes stimulated emission and gain; the relevant concepts in electromagnetic field theory; and the modes in laser structures. The relation between electrical and optical properties of laser diodes; epitaxial technology; binary III-V compounds; and diode fabrication are also consider

  11. Extracting light out of LEDs

    Science.gov (United States)

    Muschaweck, Julius; Wiesmann, Christopher

    2013-08-01

    `External quantum efficiency', that is, the number of photons generated per electron passing through the p-n junction of an LED is probably the most important number to quantify the performance of an LED chip. Although advances in epitaxy have increased the fraction of radiative recombination to extremely high values, the extraction of the precious photons that are trapped in a high refractive index crystal is still tricky. In this brief tutorial, we look at the physics of light extraction both from a geometrical optics/thermodynamic and a wave optics point of view, discussing both random and deterministic surface structures.

  12. White LED motorcycle headlamp design

    Science.gov (United States)

    Sun, Wen-Shing

    2015-09-01

    The motorcycle headlamp is composed of a white LED module, an elliptical reflector, a parabolic reflector and a toric lens. We use non-sequential ray to improve the optical efficiency of the compound reflectors. Using the toric lens can meet ECE_113 regulation and obtain a good uniformity.

  13. UV-LED photopolymerised monoliths

    Czech Academy of Sciences Publication Activity Database

    Abele, S.; Nie, F.; Foret, František; Paull, B.; Macka, M.

    2008-01-01

    Roč. 133, č. 7 (2008), s. 864-866 ISSN 0003-2654 R&D Projects: GA AV ČR KAN400310651 Institutional research plan: CEZ:AV0Z40310501 Keywords : photopolymerisation * UV-LED * polymethacrylate monolith Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 3.761, year: 2008

  14. Architecture-Led Safety Process

    Science.gov (United States)

    2016-12-01

    Contents Acknowledgments iv Abstract v 1 Introduction 1 2 Architecture -Led Processes and ALSA 2 3 ALSA Practices 5 3.1 Example System 8 4 Identify... Architecture Models 13 5 Identify Operational Hazards and Hazard Contributors 15 5.1 System Partitioning 15 5.2 Operational Context as a Control

  15. African Traditional Knowledge Systems and Biodiversity Management

    African Journals Online (AJOL)

    There is a link between African Traditional Knowledge Systems and the management of Biodiversity. These have been passed over from one generation to the next through oral tradition. The lack of documentation of these systems of managing biodiversity has led to the existence of a gap between the scientifi cally based ...

  16. Traditional medicine use and the anaesthetist

    African Journals Online (AJOL)

    GD Nethathe

    This review considers traditional medicine, with an emphasis on traditional African medicine and its influence on perioperative care. Western and Eastern herbal remedies are widely used. The paucity of good quality evidence concerning these medicinal products has led to only some of the effects of these medicines being ...

  17. LED lamp power management system and method

    Science.gov (United States)

    Gaines, James; Clauberg, Bernd; Van Erp, Josephus A. M.

    2013-03-19

    An LED lamp power management system and method including an LED lamp having an LED controller 58; a plurality of LED channels 60 operably connected to the LED controller 58, each of the plurality of LED channels 60 having a channel switch 62 in series with at least one shunted LED circuit 83, the shunted LED circuit 83 having a shunt switch 68 in parallel with an LED source 80. The LED controller 58 reduces power loss in one of the channel switch 62 and the shunt switch 68 when LED lamp electronics power loss (P.sub.loss) exceeds an LED lamp electronics power loss limit (P.sub.lim); and each of the channel switches 62 receives a channel switch control signal 63 from the LED controller 58 and each of the shunt switches 68 receives a shunt switch control signal 69 from the LED controller 58.

  18. LED lamp color control system and method

    Science.gov (United States)

    Gaines, James; Clauberg, Bernd; Van Erp, Josephus A.M.

    2013-02-05

    An LED lamp color control system and method including an LED lamp having an LED controller 58; and a plurality of LED channels 60 operably connected to the LED controller 58, each of the plurality of LED channels 60 having a channel switch 62 in series with at least one shunted LED circuit 83, the shunted LED circuit 83 having a shunt switch 68 in parallel with an LED source 80. The LED controller 58 determines whether the LED source 80 is in a feedback controllable range, stores measured optical flux for the LED source 80 when the LED source 80 is in the feedback controllable range, and bypasses storing the measured optical flux when the LED source 80 is not in the feedback controllable range.

  19. Celebrity-led development organisations

    DEFF Research Database (Denmark)

    Budabin, Alexandra Cosima; Rasmussen, Louise Mubanda; Richey, Lisa Ann

    2017-01-01

    The past decade has seen a frontier open up in international development engagement with the entrance of new actors such as celebrity-led organisations. We explore how such organisations earn legitimacy with a focus on Madonna’s Raising Malawi and Ben Affleck’s Eastern Congo Initiative. The study...... draws from organisational materials, interviews, mainstream news coverage, and the texts of the celebrities themselves to investigate the construction of authenticity, credibility, and accountability. We find these organisations earn legitimacy and flourish rapidly amid supportive elite networks...... for funding, endorsements, and expertise. We argue that the ways in which celebrity-led organisations establish themselves as legitimate development actors illustrate broader dynamics of the machinery of development....

  20. Luminescent ceramics for LED conversion

    Science.gov (United States)

    Raukas, M.; Wei, G.; Bergenek, K.; Kelso, J.; Zink, N.; Zheng, Y.; Hannah, M.; Stough, M.; Wirth, R.; Linkov, A.; Jermann, F.; Eisert, D.

    2011-03-01

    Many LED-based applications would benefit from more efficient and/or high lumen output devices that enable usage in both white and single color illumination schemes. In the present article we briefly review the materials research history leading to optical ceramic converters and discuss their typical characteristics. Recently demonstrated high performance values in terms of efficacy and external quantum efficiency in orange (amber) spectral region are described.

  1. Automotive LED lamp lighted appearance

    Science.gov (United States)

    Conn, Lawrence G.; Bennett, Larry R.

    2001-05-01

    The automotive optical engineer has an entirely new set of rules to follow for a 'smooth lighted appearance' with the introduction of LEDs into the automotive signal lighting market. To move away from the 'polka-dot' appearance long associated with the usage of LEDs as the light source for automotive lighting, and give the consumer a smooth lighted appearance to his lamp, there are several optical parameters that must be observed. The number and type of LEDs used, the size of the optical elements used, the spacing of the optical elements, plus many other factors all play a critical role and must be considered in the solution to the 'smooth lighted appearance' in an automotive signal lamp. The 'smooth lighted appearance' in an automotive signal lamp has long been a difficult problem to which there is more than one solution. The most visually pleasing and effective solution is not always the most easily obtainable solution since photometry requirements and smooth lighted appearance can be diametric goals. Subsequently the most cost effective and the easily 'doable' solution may not give the ultimate in aesthetically pleasing results for the consumer. Therefore, it is the purpose and intent of this paper to outline the parameters that need to be considered to obtain a 'smooth lighted appearance' for an automotive signal lamp, and to clarify the methods and 'tools' that are required to meet this goal.

  2. Design of LED projector based on gradient-index lens

    Science.gov (United States)

    Qian, Liyong; Zhu, Xiangbing; Cui, Haitian; Wang, Yuanhang

    2018-01-01

    In this study, a new type of projector light path is designed to eliminate the deficits of existing projection systems, such as complex structure and low collection efficiency. Using a three-color LED array as the lighting source, by means of the special optical properties of a gradient-index lens, the complex structure of the traditional projector is simplified. Traditional components, such as the color wheel, relay lens, and mirror, become unnecessary. In this way, traditional problems, such as low utilization of light energy and loss of light energy, are solved. With the help of Zemax software, the projection lens is optimized. The optimized projection lens, LED, gradient-index lens, and digital micromirror device are imported into Tracepro. The ray tracing results show that both the utilization of light energy and the uniformity are improved significantly.

  3. Medical students' learning from patient-led teaching

    DEFF Research Database (Denmark)

    Henriksen, Ann-Helen; Ringsted, Charlotte

    2014-01-01

    a patient-centred approach, and acknowledged the importance of the PIs' individual perspectives and experiential knowledge. On the other hand, representing the scientific biomedical perspective and traditional step-by step teaching, students expressed unfamiliarity with the unstructured experiential......The aim of this study was to explore how medical students perceive the experience of learning from patient instructors (patients with rheumatism who teach health professionals and students) in the context of coupled faculty-led and patient-led teaching session. This was an explorative study...... learning and scepticism regarding the credibility of the patients' knowledge. This study contributes to the understanding of the complexity of involving patients as teachers in healthcare education and initiates a discussion on how to complement faculty-led teaching with patient-led teaching involving...

  4. Spectral Design Flexibility of LED Brings Better life

    DEFF Research Database (Denmark)

    Ou, Haiyan; Corell, Dennis Dan; Ou, Yiyu

    2012-01-01

    white light using different color mixing schemes. The spectral design flexibility of white LED light sources will promote them for novel applications to improve the life quality of human beings. As an initial exploration to make use of the spectral design flexibility, we present an example: 'no blue...... longer time than the standard light source. At last future perspectives on spectral design flexibility of LED light sources improving human being's life will be discussed, with focus on the light and health. The good health is ensured by the spectrum optimized so that vital hormones (melatonin......Light-emitting diodes (LEDs) are penetrating into the huge market of general lighting because they are energy saving and environmentally friendly. The big advantage of LED light sources, compared to traditional incandescent lamps and fluorescent light tubes, is the flexible spectral design to make...

  5. Spectral design flexibility of LED brings better life

    Science.gov (United States)

    Ou, Haiyan; Corell, Dennis; Ou, Yiyu; Poulsen, Peter B.; Dam-Hansen, Carsten; Petersen, Paul-Michael

    2012-03-01

    Light-emitting diodes (LEDs) are penetrating into the huge market of general lighting because they are energy saving and environmentally friendly. The big advantage of LED light sources, compared to traditional incandescent lamps and fluorescent light tubes, is the flexible spectral design to make white light using different color mixing schemes. The spectral design flexibility of white LED light sources will promote them for novel applications to improve the life quality of human beings. As an initial exploration to make use of the spectral design flexibility, we present an example: 'no blue' white LED light source for sufferers of disease Porphyria. An LED light source prototype, made of high brightness commercial LEDs applying an optical filter, was tested by a patient suffering from Porphyria. Preliminary results have shown that the sufferer could withstand the light source for much longer time than the standard light source. At last future perspectives on spectral design flexibility of LED light sources improving human being's life will be discussed, with focus on the light and health. The good health is ensured by the spectrum optimized so that vital hormones (melatonin and serotonin) are produced during times when they support human daily rhythm.

  6. Vision communications based on LED array and imaging sensor

    Science.gov (United States)

    Yoo, Jong-Ho; Jung, Sung-Yoon

    2012-11-01

    In this paper, we propose a brand new communication concept, called as "vision communication" based on LED array and image sensor. This system consists of LED array as a transmitter and digital device which include image sensor such as CCD and CMOS as receiver. In order to transmit data, the proposed communication scheme simultaneously uses the digital image processing and optical wireless communication scheme. Therefore, the cognitive communication scheme is possible with the help of recognition techniques used in vision system. By increasing data rate, our scheme can use LED array consisting of several multi-spectral LEDs. Because arranged each LED can emit multi-spectral optical signal such as visible, infrared and ultraviolet light, the increase of data rate is possible similar to WDM and MIMO skills used in traditional optical and wireless communications. In addition, this multi-spectral capability also makes it possible to avoid the optical noises in communication environment. In our vision communication scheme, the data packet is composed of Sync. data and information data. Sync. data is used to detect the transmitter area and calibrate the distorted image snapshots obtained by image sensor. By making the optical rate of LED array be same with the frame rate (frames per second) of image sensor, we can decode the information data included in each image snapshot based on image processing and optical wireless communication techniques. Through experiment based on practical test bed system, we confirm the feasibility of the proposed vision communications based on LED array and image sensor.

  7. Parent-led or baby-led? Associations between complementary feeding practices and health-related behaviours in a survey of New Zealand families

    OpenAIRE

    Cameron, Sonya L; Taylor, Rachael W; Heath, Anne-Louise M

    2013-01-01

    Objective To determine feeding practices and selected health-related behaviours in New Zealand families following a ?baby-led? or more traditional ?parent-led? method for introducing complementary foods. Design, setting and participants 199 mothers completed an online survey about introducing complementary foods to their infant. Participants were classified into one of four groups: ?adherent baby-led weaning (BLW)?, the infant mostly or entirely fed themselves at 6?7?months; ?self-identified ...

  8. Practical lighting design with LEDs

    CERN Document Server

    Lenk, Ron

    2011-01-01

    "This book covers all of the information needed to design LEDs into end-products. It is a practical guide, primarily explaning how things are done by practicing engineers. Equations are used only for practical calculations, and are kept to the level of high-school algebra. There are numerous drawings and schematics showing how things such as measurements are actually made, and showing curcuits that actually work. There are practical notes and examples embedded in the text that give pointers and how-to guides on many of the book's topics. After reading each chapter of the book, readers will have the knowledge to implement practical designs. This book will be kept as a reference tool for years to come"--

  9. Peer-led prenatal breast-feeding education: a viable alternative to nurse-led education.

    Science.gov (United States)

    Rempel, Lynn A; Moore, Katrina C J

    2012-02-01

    To evaluate a prenatal breast-feeding class developed and facilitated by peer Breast-feeding Buddies. Non-equivalent control group quasi-experimental study comparing participants of the peer-led class (PLC) to those attending an established hospital-based breast-feeding nurse-led class (NLC). A brief questionnaire was completed immediately prior to the class, and telephone interviews were conducted approximately one week following the class, and one and six months post partum. 54 expectant mothers who registered for the community PLC and 55 expectant mothers who registered for the NLC. Breast-feeding intentions were measured at all time-points. Class evaluations, breast-feeding experiences, and breast-feeding support were measured at all post-class interviews. Both classes were considered worthwhile, but the PLC class was rated as more helpful and participants appreciated learning from the peers' personal experiences. Mothers taught by peers were more likely to access peer breast-feeding support. PLC participants initially decreased their prenatal breast-feeding duration intentions but had significantly stronger intentions to continue breast feeding at six months than did NLC mothers. A peer-led prenatal breast-feeding class is as effective as a traditional model of breast-feeding education and is a valuable tool to promote and support successful breast feeding. RECOMMENDATIONS FOR PRACTICE: Peer-led breast-feeding classes should be provided to enhance the accessibility of breast-feeding education and support for expectant mothers. Copyright © 2010 Elsevier Ltd. All rights reserved.

  10. Peer-Led Team Learning Helps Minority Students Succeed.

    Science.gov (United States)

    Snyder, Julia J; Sloane, Jeremy D; Dunk, Ryan D P; Wiles, Jason R

    2016-03-01

    Active learning methods have been shown to be superior to traditional lecture in terms of student achievement, and our findings on the use of Peer-Led Team Learning (PLTL) concur. Students in our introductory biology course performed significantly better if they engaged in PLTL. There was also a drastic reduction in the failure rate for underrepresented minority (URM) students with PLTL, which further resulted in closing the achievement gap between URM and non-URM students. With such compelling findings, we strongly encourage the adoption of Peer-Led Team Learning in undergraduate Science, Technology, Engineering, and Mathematics (STEM) courses.

  11. LEDs light up the world

    Energy Technology Data Exchange (ETDEWEB)

    Mather, N.

    2004-06-30

    A lighting system using light-emitting diodes, and privately financed by a Canadian engineering professor at the University of Calgary, has been set up in a village in Nepal in 2000. Since then, through the efforts of the 'Light Up The World' Foundation, established by Dr. Irvine-Halliday, projects have lit up thousands of homes in the Philippines, India, Afghanistan, the Galapagos Islands, Mexico, Sri Lanka, and Angola. Although the goal of the project is primarily to provide lighting for reading and writing for school-children, the project has been the source of many other advantages; creation of enterprise, increased employment, enhanced income, gender equality, and improvements in health and safety among them. Since LED lamps in most cases replace kerosene lamps, the system also has significant environmental benefits. The system as originally envisioned creates electricity by pedal-powered generator, or by solar panels connected to a battery, depending on what is available at each home. Each home is connected to the power supply and supplied with low-energy diode lamps. The lights are extremely efficient and many homes can be equipped with them using less energy than it takes to power a single 100-watt light bulb. 5 photos.

  12. UV-LEDs Efficiently Inactivate DNA and RNA Coliphages

    Directory of Open Access Journals (Sweden)

    Alyaa M. Zyara

    2017-01-01

    Full Text Available UV-LEDs are a new method of disinfecting drinking water. Some viruses are very resistant to UV and the efficiency of UV-LEDs to disinfect them needs to be studied. Drinking water was disinfected with UV-LEDs after spiking the water with MS2 and four UV- and/or Cl-resistant coliphages belonging to RNA or DNA coliphages isolated from municipal wastewater. UV-LEDs operating at a wavelength of 270 nm for 2 min with 120 mW of irradiation caused 0.93–2.73 Log10-reductions of coliphages tested in a reactor of a 5.2 L volume. Irradiation time of 10 min in the same system increased the Log10-reductions to 4.30–5.16. Traditional mercury UV (Hg-UV lamp at a 254 nm wavelength caused 0.67–4.08 Log10-reductions in 2 min and 4.56–7.21 Log10-reductions in 10 min in 10 mL of water. All coliphages tested except MS2 achieved 4 Log10-reductions with UV-LEDs at a dose that corresponded to 70 mWs/cm2 using Hg-UV. Thus, UV-LEDs are a promising method of disinfecting UV- and/or Cl-resistant viruses.

  13. High-performance LED luminaire for sports hall

    Science.gov (United States)

    Lee, Xuan-Hao; Yang, Jin-Tsung; Chien, Wei-Ting; Chang, Jung-Hsuan; Lo, Yi-Chien; Lin, Che-Chu; Sun, Ching-Cherng

    2015-09-01

    In this paper, we present a luminaire design with anti-glare and energy-saving effects for sports hall. Compared with traditional lamps using in a badminton court, the average illuminance on the ground of the proposed LED luminaire is enhanced about 300%. Besides, the uniformity is obviously enhanced and improved. The switch-on speed of lighting in sports hall is greatly reduced from 5-10 minutes to 1 second. The simulation analysis and the corresponding experiment results are demonstrated.

  14. Study on methodology of LED's luminous flux measurement with integrating sphere

    International Nuclear Information System (INIS)

    Liu Muqing; Zhou Xiaoli; Li Wenyi; Chen Yuyang; Zhang Wanlu

    2008-01-01

    Errors are introduced when using traditional methods for measuring the total luminous flux of LEDs since an LED is quite different from traditional light sources in terms of physical size, flux level, spectrum and spatial distribution. This paper uses commercial lighting simulation software named Tracepro to simulate the self-absorption effect when using traditional integrating sphere methods to measure the total luminous flux of LEDs and then presents a modified method for the measurement. The LED under investigation or a specially designed narrow beam standard lamp is placed on the interior wall of the sphere in our method. The results show that the measurement method presented here can lead to better precision in the evaluation of the total luminous flux of LEDs

  15. Self-aligning LED-based optical link

    Science.gov (United States)

    Shen, Thomas C.; Drost, Robert J.; Rzasa, John R.; Sadler, Brian M.; Davis, Christopher C.

    2016-09-01

    The steady advances in light-emitting diode (LED) technology have motivated the use of LEDs in optical wireless communication (OWC) applications such as indoor local area networks (LANs) and communication between mobile platforms (e.g., robots, vehicles). In contrast to traditional radio frequency (RF) wireless communication, OWC utilizes electromagnetic spectrum that is largely unregulated and unrestricted. OWC communication may be especially useful in RF-denied environments, in which RF communication may be prohibited or undesirable. However, OWC does present some challenges, including the need to maintain alignment between potentially moving nodes. We describe a novel system for link alignment that is composed of a hyperboloidal mirror, camera, and gimbal. The experimental system is able to use the mirror and camera to detect an LED beacon of a neighboring node and estimate its bearing (azimuth and elevation), point the gimbal towards the beacon, and establish an optical link.

  16. Control and Driving Methods for LED Based Intelligent Light Sources

    DEFF Research Database (Denmark)

    Beczkowski, Szymon

    High power light-emitting diodes allow the creation of luminaires capable of generating saturated colour light at very high efficacies. Contrary to traditional light sources like incandescent and high-intensity discharge lamps, where colour is generated using filters, LEDs use additive light mixing......, where the intensity of each primary colour diode has to be adjusted to the needed intensity to generate specified colour. The function of LED driver is to supply the diode with power needed to achieve the desired intensity. Typically, the drivers operate as a current source and the intensity...... of the diode is controlled either by varying the magnitude of the current or by driving the LED with a pulsed current and regulate the width of the pulse. It has been shown previously, that these two methods yield different effects on diode's efficacy and colour point. A hybrid dimming strategy has been...

  17. LED lighting for greenhouses. Final report; LED belysning til vaeksthuse. Slutrapport

    Energy Technology Data Exchange (ETDEWEB)

    OEstergaard, J.E. (Syddansk Univ. (SDU). Erhvervsinnovation og Teknologi, Odense (Denmark))

    2011-01-15

    The project had 3 main objectives: 1) To develop a prototype of a LED-based luminaire that can replace the existing glasshouse horticultural lighting. The project have developed a working prototype and experimentally replaced the traditional HPS luminaires in a controlled growing area. The project succeeded in producing plants of comparable quality. However, the project shows that the prototype can be improved by: x) being further integrated into the existing horticultural production technology (eg climate computers and purchase of electricity) x) adapting configuration of luminaires specifically to each plant variety x) adapting different cooling technologies to match specific customer needs x) In some cases being combined with heat input to optimize the overall economy. 2) To achieve an effective electricity savings of 50-80% - equivalent to a value of approx. DKK 5 million for a medium sized nursery. The verified electricity savings was 40%. In test setups and in well defined and controllable production areas the prototypes achieved electricity savings of > 50%. It is expected that a new generation of LEDs (Q3 2010) will allow for greater power savings. 3) To continue prototype development and initiate commercialization of the project through the company Fionia Lighting A/S. The shareholders of the company have allocated capital to the company to allow us to address the main challenges in commercializing the technology. It is expected that the company will enter a strategic alliance with a major industrial player in the beginning of 2011. (Author)

  18. Fokusgruppeinterview som led i en evalueringsproces

    DEFF Research Database (Denmark)

    Andersen-Mølgaard, Hanna; Harrit, Ole

    2006-01-01

    Teoretiske begrundelser og perspektiver, responsiv-konstruktivistisk evaluering, fokusgruppeinterview som led i BIKVAmodellen, eksempler, vurdering og perspektivering......Teoretiske begrundelser og perspektiver, responsiv-konstruktivistisk evaluering, fokusgruppeinterview som led i BIKVAmodellen, eksempler, vurdering og perspektivering...

  19. Evaluation of LED vehicular and pedestrian modules.

    Science.gov (United States)

    2009-04-01

    This study was conducted to verify the compliance of vehicular and pedestrian LED traffic signal modules with the Institute : of Transportation Engineers specifications; and to assess drivers preferences of the LED modules. Four vehicular modules ...

  20. Application of ultraviolet light-emitting diodes (UV-LEDs) for water disinfection: A review.

    Science.gov (United States)

    Song, Kai; Mohseni, Madjid; Taghipour, Fariborz

    2016-05-01

    Ultraviolet (UV) disinfection is an effective technology for the inactivation of pathogens in water and is of growing interest for industrial application. A new UV source - ultraviolet light-emitting diode (UV-LED) - has emerged in the past decade with a number of advantages compared to traditional UV mercury lamps. This promising alternative raises great interest in the research on application of UV-LEDs for water treatment. Studies on UV-LED water disinfection have increased during the past few years. This article presents a comprehensive review of recent studies on UV-LEDs with various wavelengths for the inactivation of different microorganisms. Many inconsistent and incomparable data were found from published studies, which underscores the importance of establishing a standard protocol for studying UV-LED inactivation of microorganisms. Different UV sensitivities to UV-LEDs and traditional UV lamps were observed in the literature for some microorganisms, which requires further investigation for a better understanding of microorganism response to UV-LEDs. The unique aspects of UV-LEDs improve inactivation effectiveness by applying LED special features, such as multiple wavelengths and pulsed illumination; however, more studies are needed to investigate the influencing factors and mechanisms. The special features of UV-LEDs offer the flexibility of novel reactor designs for a broad application of UV-LED reactors. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. LED belichting tijdens het voortrekken van lelie

    NARCIS (Netherlands)

    Kok, B.J.; Wildschut, J.

    2010-01-01

    De laatste jaren staat het gebruik van LED-lampen in de tuinbouw in de belangstelling. Uit vele onderzoeken is al gebleken dat LED-lampen op dit moment nog geen alternatief zijn voor de SON-T lampen. Het grote voordeel van LED-lampen is dat ze monochromatisch licht van alle mogelijke golflengtes

  2. ‘No Blue’ White LED

    DEFF Research Database (Denmark)

    Ou, Haiyan; Corell, Dennis Dan; Dam-Hansen, Carsten

    2010-01-01

    This paper explored the feasibility of making a white LED light source by color mixing method without using the blue color. This ‘no blue’ white LED has potential applications in photolithography room illumination, medical treatment and biophotonics research. A no-blue LED was designed, and the p...

  3. Color Maintenance of LEDs in Laboratory and Field Applications

    Energy Technology Data Exchange (ETDEWEB)

    Royer, Michael P.; Tuttle, Ralph; Rosenfeld, Scott M.; Miller, Naomi J.

    2013-09-30

    Synopsis: To date, consideration for parametric failure of LED products has largely been focused on lumen maintenance. However, color shift is a cause of early failure for some products, and is especially important to consider in certain applications, like museums, where visual appearance is critical. Example data collected by the GATEWAY program for LED lamps installed in museums shows that many have changed color beyond a reasonable tolerance well before their rated lifetime was reached, necessitating replacement. Similar data collected by the CALiPER program between 2008 and 2010 reveals that many early products shifted beyond acceptable tolerances in as little as a few thousand hours. In contrast, data from the L Prize program illustrates that commercially available LED products can have exemplary color stability that is unmatched by traditional light sources. Beyond presenting data from the aforementioned DOE programs, this report discusses the metrics used for communicating color shift—namely MacAdam ellipses and Δu'v'—as well as providing guidance for end users on how to monitor color shift and what to look for in manufacturer warranties. Also included are descriptions of the physical changes that have been documented as leading to color shift in some example types of LED packages. As with complete products, the data presented herein for LED packages shows that a wide variety of products are available; in order for specifiers and consumers to make educated choices, more detailed and standardized information should be made available.

  4. Plant growth with Led lighting systems

    International Nuclear Information System (INIS)

    Campiotti, C.A.; Bernardini, A.; Di Carlo, F.; Scoccianti, M.; Alonzo, G.; Carlino, M.; Dondi, F.; Bibbiani, C.

    2009-01-01

    Leds lighting is highly relevant for the horticultural industry. Compared to other light sources used for plant production, leds have several properties which are potentially useful in relation to horticulture. However, although LEDs technology has raised strong interest in research for extraterrestrial agriculture, current LEDs panel costs are still too high for commercial adoption in greenhouse sector, and their electrical efficacies do not compete with those of high-pressure sodium lamps, but several manufactures are working to address these issues. When LEDs become practical, their ability to based light sources specifically suitable for photosynthesis and other horticulturally relevant plant properties (i.e. low radiated heat; lighting from within the canopy) will render the narrow band spectrum of LEDs of particular interest for providing light to greenhouse horticulture. A general description of LEDs application and their technical characteristics is briefly reported. [it

  5. Generation of solar spectrum by using LEDs

    Science.gov (United States)

    Lu, Pengzhi; Yang, Hua; Pei, Yanrong; Li, Jing; Xue, Bin; Wang, Junxi; Li, Jinmin

    2016-09-01

    Light emitting diode (LED) has been recognized as an applicable light source for indoor and outdoor lighting, city beautifying, landscape facilities, and municipal engineering etc. Conventional LED has superior characteristics such as long life time, low power consumption, high contrast, and wide viewing angle. Recently, LED with high color-rendering index and special spectral characteristics has received more and more attention. This paper is intended to report a solar spectrum simulated by multichip LED light source. The typical solar spectrum of 5500k released by CIE was simulated as a reference. Four types of LEDs with different spectral power distributions would be used in the LED light source, which included a 430nm LED, a 480nm LED, a 500nm LED and a white LED. In order to obtain better simulation results, the white LED was achieved by a 450nm LED chip with the mixture of phosphor. The phosphor combination was prepared by mixing green phosphor, yellow phosphor and red phosphor in a certain proportion. The multichip LED light source could provide a high fidelity spectral match with the typical solar spectrum of 5500k by adjusting injection current to each device. The luminous flux, CIE chromaticity coordinate x, y, CCT, and Ra were 104.7 lm, 0.3337, 0.3681, 5460K, and 88.6, respectively. Because of high color-rendering index and highly match to the solar spectrum, the multichip LED light source is a competitive candidate for applications where special spectral is required, such as colorimetric measurements, visual inspection, gemstone identification and agriculture.

  6. Understanding traditional African healing.

    Science.gov (United States)

    Mokgobi, M G

    2014-09-01

    Traditional African healing has been in existence for many centuries yet many people still seem not to understand how it relates to God and religion/spirituality. Some people seem to believe that traditional healers worship the ancestors and not God. It is therefore the aim of this paper to clarify this relationship by discussing a chain of communication between the worshipers and the Almighty God. Other aspects of traditional healing namely types of traditional healers, training of traditional healers as well as the role of traditional healers in their communities are discussed. In conclusion, the services of traditional healers go far beyond the uses of herbs for physical illnesses. Traditional healers serve many roles which include but not limited to custodians of the traditional African religion and customs, educators about culture, counselors, social workers and psychologists.

  7. TRADITIONAL REMEDIES IN CHILDREN AROUND EASTERN ...

    African Journals Online (AJOL)

    hi-tech

    2003-08-08

    Aug 8, 2003 ... remain largely unproven by the scientific method and the concern about adverse effects have led to closer scrutiny of these products (4). Whereas most traditional remedies are safe, the potential for adverse effects or intoxication exists, as does the possibility of interaction with conventional drugs (2, 5-8).

  8. Testing Finance-Led, Export-Led and Import-Led Growth Hypotheses on Four Sub-Saharan African Economies

    OpenAIRE

    Evans, Olaniyi

    2013-01-01

    This study carries out an empirical examination of the finance-led, export-led and import-led growth hypothesis for four of the largest Sub-Saharan African economies namely South Africa, Nigeria, Ghana and Kenya. Within a multivariate Vector-Auto Regressive (VAR) framework, the concept of Granger causality is employed to determine the direction of causation between exports and output, duly taking into account the stationarity properties of the time series data. With further substantiation fro...

  9. Efficiency and Droop Improvement in GaN-Based High-Voltage Flip Chip LEDs

    Directory of Open Access Journals (Sweden)

    Yen-Chih Chiang

    2014-01-01

    Full Text Available The GaN-based high-voltage flip chip light-emitting diode (HVFC-LED is designed and developed for the purpose of efficiency enhancement. In our design, the distributed Bragg reflector (DBR is deposited at the bonded substrate to increase the light extraction. After the flip chip process, the general current-voltage characteristics between the flip chip sample and the traditional sample are essentially the same. With the help of great thermal conductive silicon substrate and the bottom DBR, the HVFC-LED is able to enhance the power by 37.1% when compared to the traditional high-voltage LEDs. The wall-plug efficiencies of the HVFC-LED also show good droop reduction as high as 9.9% compared to the traditional devices.

  10. Traditional Agriculture and Permaculture.

    Science.gov (United States)

    Pierce, Dick

    1997-01-01

    Discusses benefits of combining traditional agricultural techniques with the concepts of "permaculture," a framework for revitalizing traditions, culture, and spirituality. Describes school, college, and community projects that have assisted American Indian communities in revitalizing sustainable agricultural practices that incorporate…

  11. LEDs for general and horticultural lighting

    OpenAIRE

    Girón González, Emilio

    2012-01-01

    The work begins with an introductory part about Light Emitting Diode (or LEDs) and how these devices work. This report also shows an overview of different artificial light sources such as incandescent lamps, fluorescents tube and high-intensity discharge (HID) lamps. The LED lighting is more energy-efficient than other artificial lighting, since they require less energy to operate. The following part of the work reports LEDs for General Lighting that describes some basic concepts such as spec...

  12. System Reliability for LED-Based Products

    Energy Technology Data Exchange (ETDEWEB)

    Davis, J Lynn; Mills, Karmann; Lamvik, Michael; Yaga, Robert; Shepherd, Sarah D; Bittle, James; Baldasaro, Nick; Solano, Eric; Bobashev, Georgiy; Johnson, Cortina; Evans, Amy

    2014-04-07

    Results from accelerated life tests (ALT) on mass-produced commercially available 6” downlights are reported along with results from commercial LEDs. The luminaires capture many of the design features found in modern luminaires. In general, a systems perspective is required to understand the reliability of these devices since LED failure is rare. In contrast, components such as drivers, lenses, and reflector are more likely to impact luminaire reliability than LEDs.

  13. Solid State Lighting LED Manufacturing Roundtable Summary

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2010-03-31

    Summary of a meeting of LED experts to develop proposed priority tasks for the Manufacturing R&D initiative, including task descriptions, discussion points, recommendations, and presentation highlights.

  14. Storybooks aren't just for fun: narrative and non-narrative picture books foster equal amounts of generic language during mother-toddler book sharing.

    Science.gov (United States)

    Nyhout, Angela; O'Neill, Daniela K

    2014-01-01

    Parents and children encounter a variety of animals and objects in the early picture books they share, but little is known about how the context in which these entities are presented influences talk about them. The present study investigated how the presence or absence of a visual narrative context influences mothers' tendency to refer to animals as individual characters or as members of a kind when sharing picture books with their toddlers (mean age 21.3 months). Mother-child dyads shared both a narrative and a non-narrative book, each featuring six animals and matched in terms of length and quantity of text. Mothers made more specific (individual-referring) statements about animals in the narrative books, whereas they provided more labels for animals in the non-narrative books. But, of most interest, the frequency and proportion of mothers' use of generic (kind-referring) utterances did not differ across the two different types of books. Further coding of the content of the utterances revealed that mothers provided more story-specific descriptions of states and actions of the animals when sharing narrative books and more physical descriptions of animals when sharing non-narrative books. However, the two books did not differ in terms of their elicitation of natural facts about the animals. Overall, although the two types of books encouraged different types of talk from mothers, they stimulated generic language and talk about natural facts to an equal degree. Implications for learning from picture storybooks and book genre selection in classrooms and home reading are discussed.

  15. Languaging in and about Lunyole: African Storybook materials as a catalyst for re-imagining literacy teaching and learning in two Ugandan primary schools

    Directory of Open Access Journals (Sweden)

    Juliet Tembe

    2016-07-01

    Full Text Available Throughout sub-Saharan Africa, many children are not learning to read competently in the first 3 years of primary school; thus, both ‘reading to learn’ and ‘reading for pleasure’ in these early years, and in higher grades, are constrained. Two of the many reasons for reading failure are the absence of suitable materials in languages with which learners are familiar and teachers’ limited knowledge of pedagogic practices that support reading development. In this article, we describe the African Storybook (ASb initiative as one imaginative response to the dearth of interesting and accessible stories in local languages and report findings from the first phase of a professional development project in which teacher-researchers in two Ugandan schools are using ASb materials to ‘language’ in Lunyole at the meetings of their action research group. We argue that their investment in extending their literacy in a language which they speak more fluently than they read or write, and the contestations over written forms of this language that have surfaced in some of the discussions, are likely to be productive for their professional development as teachers and for their participation in ongoing community debates about the orthography of a recently codified and standardised language. By languaging together in Lunyole, with ASb materials as the main object of their conversations and activities, the teacher-researchers have begun to develop capabilities that are likely to benefit the Lunyole/ English biliteracy of the learners whom they teach. They are imagining new possibilities for themselves and for the learners.

  16. A fast template matching method for LED chip Localization

    Directory of Open Access Journals (Sweden)

    Zhong Fuqiang

    2015-01-01

    Full Text Available Efficiency determines the profits of the semiconductor producers. So the producers spare no effort to enhance the efficiency of every procedure. The purpose of the paper is to present a method to shorten the time to locate the LED chips on wafer. The method consists of 3 steps. Firstly, image segmentation and blob analyzation are used to predict the positions of potential chips. Then predict the orientations of potential chips based on their dominant orientations. Finally, according to the positions and orientations predicted above, locate the chips precisely based on gradient orientation features. Experiments show that the algorithm is faster than the traditional method we choose to locate the LED chips. Besides, even the orientations of the chips on wafer are of big deviation to the orientation of the template, the efficiency of this method won't be affected.

  17. LEDs: revolution or evolution? Part One

    Energy Technology Data Exchange (ETDEWEB)

    Roush, M.

    2000-11-01

    The historical evolution, the current state of light emitting diodes (LEDs), future implications and the promise of this technology for the lighting industry are explored. Some of the misconceptions relative to that promise are dispelled and some of the less obvious benefits that this technology could deliver in the future are discussed. As far as misconceptions are concerned, it is not true that LEDs will deliver light forever at a fraction of the energy of conventional light sources, or that they come in an infinite variety of colours and cost just pennies. Although LEDs per se may last a long time, the fact is that their true life expectancy is only as long as the wiring and the connection within the system, and they are certainly limited. Energy efficiency is another misconception. The truth is that white LEDs (the best for illumination purposes) are limited to less than 10 lumen per Watt, which is hardly a revolutionary improvement over incandescent light sources. Equally disappointing is the misconception concerning price. In actual fact, LEDs in lighting applications are very new and it would require mass production in the millions before LED lighting packages could become inexpensive. At the same time, LEDs have many advantages that are not commonly known. Compactness, very high level of light utilization, high life expectancy and nearly flat mortality curve are some of these. Operating on direct current lends LED installations to battery and solar applications (as for example solar LED road studs to aid in night driving). The absence of ultraviolet emissions in LEDs is another lesser known, but important feature, especially in applications where material degradation is a major concern (as in stores and museums). In general, all indicators point to a bright future for LEDs as their application progresses from decoration to illumination. This topic will be further explored in Part Two of this article. 4 figs.

  18. On the switching speed of SOI LEDs

    NARCIS (Netherlands)

    Schmitz, Jurriaan; de Vries, R.; Salm, Cora; Hoang, T.; Hueting, Raymond Josephus Engelbart; Holleman, J.

    2008-01-01

    Recently, we presented a novel design for a silicon LED in SmartCUT™ SOI wafers. It exhibits a record quantum efficiency for SOI-based silicon LEDs and opens the way to the integration of light emitters in a VLSI process on SOI. In this paper, we present first experimental and modeling results

  19. Led-licht biedt mogelijkheden in broeierij

    NARCIS (Netherlands)

    Neefjes, H.; PPO Bomen-bollen,

    2010-01-01

    Onderzoekers van PPO Lisse hebben de mogelijkheden van led-licht verkend bij met name lelie en tulp. Bij lelie bieden leds perspectief in de voortrek. Tulp kan er bijna de hele broeifase van profiteren. Veel licht is niet nodig, maar meerlagenteelt is een voorwaarde.

  20. Reduced Component Count RGB LED Driver

    NARCIS (Netherlands)

    De Pedro, I.; Ackermann, B.

    2008-01-01

    The goal of this master thesis is to develop new drive and contrololutions, for creating white light from mixing the light of different-color LEDs, aiming at a reduced component count resulting in less space required by the electronics and lower cost. It evaluates the LED driver concept proposed in

  1. Led Zeppelin reklaamib Narvat / Anti Ronk

    Index Scriptorium Estoniae

    Ronk, Anti

    2007-01-01

    Ilmus Narva-teemaline kahest CD-st koosnev album, kus ühel plaadil on 60 minutit videot linna vaatamisväärsuste ja informatsiooniga, teisel - briti rockansambli Led Zeppelini teosed Narva sümfooniaorkestri ja rockansambli Led R esituses

  2. Periodization paradigms in the 21st century: evidence-led or tradition-driven?

    Science.gov (United States)

    Kiely, John

    2012-09-01

    The planning and organization of athletic training have historically been much discussed and debated in the coaching and sports science literature. Various influential periodization theorists have devised, promoted, and substantiated particular training-planning models based on interpretation of the scientific evidence and individual beliefs and experiences. Superficially, these proposed planning models appear to differ substantially. However, at a deeper level, it can be suggested that such models share a deep-rooted cultural heritage underpinned by a common set of historically pervasive planning beliefs and assumptions. A concern with certain of these formative assumptions is that, although no longer scientifically justifiable, their shaping influence remains deeply embedded. In recent years substantial evidence has emerged demonstrating that training responses vary extensively, depending upon multiple underlying factors. Such findings challenge the appropriateness of applying generic methodologies, founded in overly simplistic rule-based decision making, to the planning problems posed by inherently complex biological systems. The purpose of this review is not to suggest a whole-scale rejection of periodization theories but to promote a refined awareness of their various strengths and weaknesses. Eminent periodization theorists-and their variously proposed periodization models-have contributed substantially to the evolution of training-planning practice. However, there is a logical line of reasoning suggesting an urgent need for periodization theories to be realigned with contemporary elite practice and modern scientific conceptual models. In concluding, it is recommended that increased emphasis be placed on the design and implementation of sensitive and responsive training systems that facilitate the guided emergence of customized context-specific training-planning solutions.

  3. Advances in LEDs for automotive applications

    Science.gov (United States)

    Bhardwaj, Jy; Peddada, Rao; Spinger, Benno

    2016-03-01

    High power LEDs were introduced in automotive headlights in 2006-2007, for example as full LED headlights in the Audi R8 or low beam in Lexus. Since then, LED headlighting has become established in premium and volume automotive segments and beginning to enable new compact form factors such as distributed low beam and new functions such as adaptive driving beam. New generations of highly versatile high power LEDs are emerging to meet these application needs. In this paper, we will detail ongoing advances in LED technology that enable revolutionary styling, performance and adaptive control in automotive headlights. As the standards which govern the necessary lumens on the road are well established, increasing luminance enables not only more design freedom but also headlight cost reduction with space and weight saving through more compact optics. Adaptive headlighting is based on LED pixelation and requires high contrast, high luminance, smaller LEDs with high-packing density for pixelated Matrix Lighting sources. Matrix applications require an extremely tight tolerance on not only the X, Y placement accuracy, but also on the Z height of the LEDs given the precision optics used to image the LEDs onto the road. A new generation of chip scale packaged (CSP) LEDs based on Wafer Level Packaging (WLP) have been developed to meet these needs, offering a form factor less than 20% increase over the LED emitter surface footprint. These miniature LEDs are surface mount devices compatible with automated tools for L2 board direct attach (without the need for an interposer or L1 substrate), meeting the high position accuracy as well as the optical and thermal performance. To illustrate the versatility of the CSP LEDs, we will show the results of, firstly, a reflector-based distributed low beam using multiple individual cavities each with only 20mm height and secondly 3x4 to 3x28 Matrix arrays for adaptive full beam. Also a few key trends in rear lighting and impact on LED light

  4. High Performance Green LEDs by Homoepitaxial

    Energy Technology Data Exchange (ETDEWEB)

    Wetzel, Christian; Schubert, E Fred

    2009-11-22

    This work's objective was the development of processes to double or triple the light output power from green and deep green (525 - 555 nm) AlGaInN light emitting diode (LED) dies within 3 years in reference to the Lumileds Luxeon II. The project paid particular effort to all aspects of the internal generation efficiency of light. LEDs in this spectral region show the highest potential for significant performance boosts and enable the realization of phosphor-free white LEDs comprised by red-green-blue LED modules. Such modules will perform at and outperform the efficacy target projections for white-light LED systems in the Department of Energy's accelerated roadmap of the SSL initiative.

  5. White LEDs with limit luminous efficacy

    Science.gov (United States)

    Lisitsyn, V. M.; Lukash, V. S.; Stepanov, S. A.; Yangyang, Ju

    2016-01-01

    In most promising widespread gallium nitride based LEDs emission is generated in the blue spectral region with a maximum at about 450 nm which is converted to visible light with the desired spectrum by means of phosphor. The thermal energy in the conversion is determined by the difference in the energies of excitation and emission quanta and the phosphor quantum yield. Heat losses manifest themselves as decrease in the luminous efficacy. LED heating significantly reduces its efficiency and life. In addition, while heating, the emission generation output and the efficiency of the emission conversion decrease. Therefore, the reduction of the energy losses caused by heating is crucial for LED development. In this paper, heat losses in phosphor-converted LEDs (hereinafter chips) during spectrum conversion are estimated. The limit values of the luminous efficacy for white LEDs are evaluated.

  6. White LEDs with limit luminous efficacy

    Energy Technology Data Exchange (ETDEWEB)

    Lisitsyn, V. M.; Stepanov, S. A., E-mail: stepanovsa@tpu.ru; Yangyang, Ju [National Research Tomsk Polytechnic University, 30 Lenin Av., Tomsk, 634050 (Russian Federation); Lukash, V. S. [JSC Research Institute of Semiconductor Devices, 99a Krasnoarmeyskaja St., Tomsk, 634050 (Russian Federation)

    2016-01-15

    In most promising widespread gallium nitride based LEDs emission is generated in the blue spectral region with a maximum at about 450 nm which is converted to visible light with the desired spectrum by means of phosphor. The thermal energy in the conversion is determined by the difference in the energies of excitation and emission quanta and the phosphor quantum yield. Heat losses manifest themselves as decrease in the luminous efficacy. LED heating significantly reduces its efficiency and life. In addition, while heating, the emission generation output and the efficiency of the emission conversion decrease. Therefore, the reduction of the energy losses caused by heating is crucial for LED development. In this paper, heat losses in phosphor-converted LEDs (hereinafter chips) during spectrum conversion are estimated. The limit values of the luminous efficacy for white LEDs are evaluated.

  7. Harmonics Monitoring Survey on LED Lamps

    Directory of Open Access Journals (Sweden)

    Abdelrahman Ahmed Akila

    2017-03-01

    Full Text Available Light Emitting Diode (LED lamps are being increasingly used in many applications. These LED lamps operate using a driver, which is a switching device. Hence, LED lamps will be a source of harmonics in the power system. These harmonics if not well treated, may cause severe performance and operational problems. In this paper, harmonics (amplitude and phase angles generated by both LED lamps and conventional fluorescent lamps will be studied practically. Then they will be analyzed and evaluated. Compared to each other harmonics generated by both LED and conventional florescent lamps, self mitigation may occur based on the phase angle of these harmonics. All data will be measured using power analyzer and will be done on a sample of actual lamps.

  8. Design of an Oximeter Based on LED-LED Configuration and FPGA Technology

    OpenAIRE

    Stojanovic, Radovan; Karadaglic, Dejan

    2013-01-01

    A fully digital photoplethysmographic (PPG) sensor and actuator has been developed. The sensing circuit uses one Light Emitting Diode (LED) for emitting light into human tissue and one LED for detecting the reflectance light from human tissue. A Field Programmable Gate Array (FPGA) is used to control the LEDs and determine the PPG and Blood Oxygen Saturation (SpO2). The configurations with two LEDs and four LEDs are developed for measuring PPG signal and Blood Oxygen Saturation (SpO2). N-LEDs...

  9. Design and Analysis of an Underwater White LED Fish-Attracting Lamp and its Light Propagation

    Directory of Open Access Journals (Sweden)

    Sheng Chih Shen

    2013-03-01

    Full Text Available Light emitting diodes (LED are a new source for replacing traditional light sources including under water illumination. As traditional underwater light sources operate under a radiative transfer model, the luminous intensity is dispersed evenly at each emission angle, with the scattering factors included in the attenuation coefficient. By contrast, LED light sources are characterized by being highly directional, causing underwater luminous energy to vary with different emission angles. Thus, the traditional theory of underwater optical transfer becomes inapplicable when an underwater LED lighting module is designed. Therefore, to construct an underwater transfer model for LED light sources, this study employed the average cosine of the underwater light field, the method for light scattering probability, the LED luminous intensity distribution curve (LIDC and axial luminous intensity. Afterwards, an underwater LED fish-attracting lamp was designed. Experimental results showed that, compared with the simulation values, the luminous intensity of the underwater LED lighting module at all emission angles had a percentage error of less than 10%.

  10. White LED with High Package Extraction Efficiency

    International Nuclear Information System (INIS)

    Yi Zheng; Stough, Matthew

    2008-01-01

    The goal of this project is to develop a high efficiency phosphor converting (white) Light Emitting Diode (pcLED) 1-Watt package through an increase in package extraction efficiency. A transparent/translucent monolithic phosphor is proposed to replace the powdered phosphor to reduce the scattering caused by phosphor particles. Additionally, a multi-layer thin film selectively reflecting filter is proposed between blue LED die and phosphor layer to recover inward yellow emission. At the end of the project we expect to recycle approximately 50% of the unrecovered backward light in current package construction, and develop a pcLED device with 80 lm/W e using our technology improvements and commercially available chip/package source. The success of the project will benefit luminous efficacy of white LEDs by increasing package extraction efficiency. In most phosphor-converting white LEDs, the white color is obtained by combining a blue LED die (or chip) with a powdered phosphor layer. The phosphor partially absorbs the blue light from the LED die and converts it into a broad green-yellow emission. The mixture of the transmitted blue light and green-yellow light emerging gives white light. There are two major drawbacks for current pcLEDs in terms of package extraction efficiency. The first is light scattering caused by phosphor particles. When the blue photons from the chip strike the phosphor particles, some blue light will be scattered by phosphor particles. Converted yellow emission photons are also scattered. A portion of scattered light is in the backward direction toward the die. The amount of this backward light varies and depends in part on the particle size of phosphors. The other drawback is that yellow emission from phosphor powders is isotropic. Although some backward light can be recovered by the reflector in current LED packages, there is still a portion of backward light that will be absorbed inside the package and further converted to heat. Heat generated

  11. FREQUENCY CHARACTERISTICS OF MODERN LED PHOSPHOR MATERIALS

    Directory of Open Access Journals (Sweden)

    Maxim S. Fudin

    2014-11-01

    Full Text Available Frequency characteristics of modern LED phosphor materials have been considered for the purpose of assessing the prospects of phosphor-based LEDs in wireless communication data systems which use optical wavelengths. The measurements have been carried out on the dependence of the emission intensity of single LEDs and LED chip-on-board modules with phosphors based on yttrium-aluminum and lutetium-aluminum garnets (with or without addition of nitridebased phosphors as well as silicate-based phosphors, on the frequency of electric pulses exciting the emission. It was shown that from the point of view of data transmission rate, garnet-based phosphors (including systems with added nitride phosphors are more promising than silicate–based ones. Garnet-based materials can be used in optical communication data systems with bandwidth (without extra modulation applied up to 3 MHz with single–chip LEDs and up to 4.5 MHz with 9- chip LED chip-on-board modules. The results of the work indicate that a significant part of white LEDs used in general lighting systems can be even now used for data transfer, for example, in systems assisting positioning in closed spaces to facilitate people searching necessary rooms or objects

  12. High Power UV LED Industrial Curing Systems

    Energy Technology Data Exchange (ETDEWEB)

    Karlicek, Robert, F., Jr; Sargent, Robert

    2012-05-14

    UV curing is a green technology that is largely underutilized because UV radiation sources like Hg Lamps are unreliable and difficult to use. High Power UV LEDs are now efficient enough to replace Hg Lamps, and offer significantly improved performance relative to Hg Lamps. In this study, a modular, scalable high power UV LED curing system was designed and tested, performing well in industrial coating evaluations. In order to achieve mechanical form factors similar to commercial Hg Lamp systems, a new patent pending design was employed enabling high irradiance at long working distances. While high power UV LEDs are currently only available at longer UVA wavelengths, rapid progress on UVC LEDs and the development of new formulations designed specifically for use with UV LED sources will converge to drive more rapid adoption of UV curing technology. An assessment of the environmental impact of replacing Hg Lamp systems with UV LED systems was performed. Since UV curing is used in only a small portion of the industrial printing, painting and coating markets, the ease of use of UV LED systems should increase the use of UV curing technology. Even a small penetration of the significant number of industrial applications still using oven curing and drying will lead to significant reductions in energy consumption and reductions in the emission of green house gases and solvent emissions.

  13. Due process traditionalism.

    Science.gov (United States)

    Sunstein, Cass R

    2008-06-01

    In important cases, the Supreme Court has limited the scope of "substantive due process" by reference to tradition, but it has yet to explain why it has done so. Due process traditionalism might be defended in several distinctive ways. The most ambitious defense draws on a set of ideas associated with Edmund Burke and Friedrich Hayek, who suggested that traditions have special credentials by virtue of their acceptance by many minds. But this defense runs into three problems. Those who have participated in a tradition may not have accepted any relevant proposition; they might suffer from a systematic bias; and they might have joined a cascade. An alternative defense sees due process traditionalism as a second-best substitute for two preferable alternatives: a purely procedural approach to the Due Process Clause, and an approach that gives legislatures the benefit of every reasonable doubt. But it is not clear that in these domains, the first-best approaches are especially attractive; and even if they are, the second-best may be an unacceptably crude substitute. The most plausible defense of due process traditionalism operates on rule-consequentialist grounds, with the suggestion that even if traditions are not great, they are often good, and judges do best if they defer to traditions rather than attempting to specify the content of "liberty" on their own. But the rule-consequentialist defense depends on controversial and probably false assumptions about the likely goodness of traditions and the institutional incapacities of judges.

  14. Kansas highway LED illumination manual : a guide for the use of LED lighting systems.

    Science.gov (United States)

    2015-12-01

    The research project was aimed to assist the Kansas Department of Transportation (KDOT) in the development of a Highway LED Illumination Manual for guiding the upcoming implementation of successful LED roadway lighting systems in Kansas to replace th...

  15. Kansas highway LED illumination manual : a guide for the use of LED lighting systems : [technical summary].

    Science.gov (United States)

    2015-12-01

    The research project was aimed to assist the Kansas Department of Transportation (KDOT) in the development of a Highway LED Illumination Manual for guiding the upcoming implementation of successful LED roadway lighting systems in Kansas to replace th...

  16. Preaching in the Lutheran Tradition

    DEFF Research Database (Denmark)

    Lorensen, Marlene Ringgaard

    2010-01-01

    of Denmark. On one hand there is a strong reformed emphasis on the belief that Preadicatio verbi dei est verbum dei - The preaching of the Word of God is the Word of God. On the other hand the majority of preachers cannot easily make themselves advocates for continuing the category, "Word of God...... the belief that proclamation demands to be understood somehow as the "Word of God".   Udgivelsesdato: October......", as a homiletical basis. The dialectical theology's attempt of reviving the category, in the middle of the 20th century, led homiletics into too grave difficulties and has been accused of great co-responsibility for the drying out of the church's preaching tradition. The claim that preaching is the Word of God has...

  17. LED traffic signal management system : final report.

    Science.gov (United States)

    2016-06-01

    This research originated from the opportunity to develop a methodology to assess when LED (Light Emitting Diode) traffic signal modules begin to fail to meet the Institute of Transportation Engineers (ITE) performance specification for luminous inten...

  18. Significant growth in. LED use predicted.

    Science.gov (United States)

    Simpson, Mike

    2012-03-01

    Although LED lighting has its critics, a number of whom (see article 'LED--panacea or marketing hype', HEJ--February 2012) are concerned about what they claim are some manufacturers' 'exaggerated claims' about lighting efficiency and lamp lifetime, Philips Lighting believes that, such are the advances being made in this innovative lighting technology, that LED's overall share of the European lighting market will have risen from around 7% in 2008 to 25% by 2020 and that, a decade later, it will account for a remarkable 75% of lighting sales. In the UK, Philips' technical and design director for Lighting, Mike Simpson, told HEJ editor, Jonathan Baillie, healthcare estates and facilities managers are increasingly recognising the potential to save energy, reduce carbon emissions, and cut maintenance costs, using LED.

  19. LED til væksthuse

    DEFF Research Database (Denmark)

    Dam-Hansen, Carsten; Thorseth, Anders; Rosenqvist, Eva

    2012-01-01

    Den teknologiske udvikling indenfor Lys Emitterende Dioder (LED) går imod stadig større lysmængder og stadig større effektivitet. Kombineret med fordele som lang levetid, dæmpbarhed og ingen varmestråling gør det, at LED baserede lyskilder/lamper i stigende grad benyttes til belysningsformål og kan...

  20. LED Shipboard Lighting: A Comparative Analysis

    Science.gov (United States)

    2009-12-01

    viability of retrofitting the Navy fleet with newer lighting technology . C. RESEARCH QUESTION The research project provided to NPS by Dr. Larry Schuette...LED is a key component in today’s lighting technology . Modern households use LEDs in such components as digital video disc, (DVD) readers...manufactures that the Navy is serious in implementing lighting technology with a multi- year demonstration seeing the benefits provided by the manufactures

  1. The High-efficiency LED Driver for Visible Light Communication Applications.

    Science.gov (United States)

    Gong, Cihun-Siyong Alex; Lee, Yu-Chen; Lai, Jyun-Liang; Yu, Chueh-Hao; Huang, Li Ren; Yang, Chia-Yen

    2016-08-08

    This paper presents a LED driver for VLC. The main purpose is to solve the low data rate problem used to be in switching type LED driver. The GaN power device is proposed to replace the traditional silicon power device of switching LED driver for the purpose of increasing switching frequency of converter, thereby increasing the bandwidth of data transmission. To achieve high efficiency, the diode-connected GaN power transistor is utilized to replace the traditional ultrafast recovery diode used to be in switching type LED driver. This work has been experimentally evaluated on 350-mA output current. The results demonstrate that it supports the data of PWM dimming level encoded in the PPM scheme for VLC application. The experimental results also show that system's efficiency of 80.8% can be achieved at 1-Mb/s data rate.

  2. The High-efficiency LED Driver for Visible Light Communication Applications

    Science.gov (United States)

    Gong, Cihun-Siyong Alex; Lee, Yu-Chen; Lai, Jyun-Liang; Yu, Chueh-Hao; Huang, Li Ren; Yang, Chia-Yen

    2016-08-01

    This paper presents a LED driver for VLC. The main purpose is to solve the low data rate problem used to be in switching type LED driver. The GaN power device is proposed to replace the traditional silicon power device of switching LED driver for the purpose of increasing switching frequency of converter, thereby increasing the bandwidth of data transmission. To achieve high efficiency, the diode-connected GaN power transistor is utilized to replace the traditional ultrafast recovery diode used to be in switching type LED driver. This work has been experimentally evaluated on 350-mA output current. The results demonstrate that it supports the data of PWM dimming level encoded in the PPM scheme for VLC application. The experimental results also show that system’s efficiency of 80.8% can be achieved at 1-Mb/s data rate.

  3. The Fine Dutch Tradition

    NARCIS (Netherlands)

    Hooimeijer, F.L.

    2012-01-01

    Publication of the exhibition and symposium on water adaptive urban planning and architecture in Bangkok. The Urban Fine Dutch Tradition is a dynamic tradition of making urban designs using the parameters of the natural system – incorperating in an efficient way the hydrological cycle, the soil and

  4. TRADITIONAL CHINESE HERBAL MEDICINE

    NARCIS (Netherlands)

    ZHU, YP; WOERDENBAG, HJ

    1995-01-01

    Herbal medicine, acupuncture and moxibustion, and massage and the three major constituent parts of traditional Chinese medicine. Although acupuncture is well known in many Western countries, Chinese herbal medicine, the mos important part of traditional Chinese medicine, is less well known in the

  5. LEDS GP Success Story: Fostering Coordinated LEDS Support in Kenya (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2014-03-01

    The LEDS Global Partnership (LEDS GP) strives to advance climate-resilient, low-emission development through catalyzing collaboration, information exchange, and action on the ground. The Government of Kenya is a key LEDS GP member and offers an inspiring example of how LEDS GP is having an impact globally. The 2012 LEDS Collaboration in Action workshop in London provided an interactive space for members to share experiences on cross-ministerial LEDS leadership and to learn about concrete development impacts of LEDS around the world. Inspired by these stories, the Kenya's Ministry of State for Planning, National Development and Vision 2030 (MPND) began to collaborate closely with the Ministry of Environment and Mineral Resources to create strong links between climate change action and development in the country, culminating in the integration of Kenya's National Climate Change Action Plan and the country's Medium Term Development Plan.

  6. Traditional medicine and genomics

    Directory of Open Access Journals (Sweden)

    Kalpana Joshi

    2010-01-01

    Full Text Available ′Omics′ developments in the form of genomics, proteomics and metabolomics have increased the impetus of traditional medicine research. Studies exploring the genomic, proteomic and metabolomic basis of human constitutional types based on Ayurveda and other systems of oriental medicine are becoming popular. Such studies remain important to developing better understanding of human variations and individual differences. Countries like India, Korea, China and Japan are investing in research on evidence-based traditional medicines and scientific validation of fundamental principles. This review provides an account of studies addressing relationships between traditional medicine and genomics.

  7. Traditional medicine and genomics.

    Science.gov (United States)

    Joshi, Kalpana; Ghodke, Yogita; Shintre, Pooja

    2010-01-01

    'Omics' developments in the form of genomics, proteomics and metabolomics have increased the impetus of traditional medicine research. Studies exploring the genomic, proteomic and metabolomic basis of human constitutional types based on Ayurveda and other systems of oriental medicine are becoming popular. Such studies remain important to developing better understanding of human variations and individual differences. Countries like India, Korea, China and Japan are investing in research on evidence-based traditional medicines and scientific validation of fundamental principles. This review provides an account of studies addressing relationships between traditional medicine and genomics.

  8. Oral Tradition and Sappho

    Directory of Open Access Journals (Sweden)

    R. Scott Garner

    2011-10-01

    Full Text Available Through an exploration of Sappho’s verse-structuring tendencies and repeated phraseology, the current essay demonstrates that Sappho’s stanzaic poetry was enabled primarily by a traditional system of composition that allowed her words to be encoded with extralexical meaning (or to use John Miles Foley’s term, “traditional referentiality”. Through a renewed appreciation of these oral traditional influences on Sappho’s poetry we thus can begin to approach an understanding of this art much closer to that held by its earliest ancient Greek audiences.

  9. Affordable underwater wireless optical communication using LEDs

    Science.gov (United States)

    Pilipenko, Vladimir; Arnon, Shlomi

    2013-09-01

    In recent years the need for high data rate underwater wireless communication (WC) has increased. Nowadays, the conventional technology for underwater communication is acoustic. However, the maximum data rate that acoustic technology can provide is a few kilobits per second. On the other hand, emerging applications such as underwater imaging, networks of sensors and swarms of underwater vehicles require much faster data rates. As a result, underwater optical WC, which can provide much higher data rates, has been proposed as an alternative means of communication. In addition to high data rates, affordable communication systems become an important feature in the development requirements. The outcome of these requirements is a new system design based on off-the-shelf components such as blue and green light emitting diodes (LEDs). This is due to the fact that LEDs offer solutions characterized by low cost, high efficiency, reliability and compactness. However, there are some challenges to be met when incorporating LEDs as part of the optical transmitter, such as low modulation rates and non linearity. In this paper, we review the main challenges facing the incorporation of LEDs as an integral part of underwater WC systems and propose some techniques to mitigate the LED limitations in order to achieve high data rate communication

  10. Building an intelligence-led security program

    CERN Document Server

    Liska, Allan

    2014-01-01

    As recently as five years ago, securing a network meant putting in a firewall, intrusion detection system, and installing antivirus software on the desktop. Unfortunately, attackers have grown more nimble and effective, meaning that traditional security programs are no longer effective. Today's effective cyber security programs take these best practices and overlay them with intelligence. Adding cyber threat intelligence can help security teams uncover events not detected by traditional security platforms and correlate seemingly disparate events across the network. Properly-implemented inte

  11. Zernike polynomials for photometric characterization of LEDs

    International Nuclear Information System (INIS)

    Velázquez, J L; Ferrero, A; Pons, A; Campos, J; Hernanz, M L

    2016-01-01

    We propose a method based on Zernike polynomials to characterize photometric quantities and descriptors of light emitting diodes (LEDs) from measurements of the angular distribution of the luminous intensity, such as total luminous flux, BA, inhomogeneity, anisotropy, direction of the optical axis and Lambertianity of the source. The performance of this method was experimentally tested for 18 high-power LEDs from different manufacturers and with different photometric characteristics. A small set of Zernike coefficients can be used to calculate all the mentioned photometric quantities and descriptors. For applications not requiring a great accuracy such as those of lighting design, the angular distribution of the luminous intensity of most of the studied LEDs can be interpolated with only two Zernike polynomials. (paper)

  12. White LED phosphors: the next step

    Science.gov (United States)

    Yamamoto, Hajime

    2010-02-01

    Application of white LEDs is extended toward high-output light sources, e.g. for automotive headlights, and better spectral matching with optical filters for LCD backlighting. To meet such new demands, phosphor materials have been investigated with focus on their luminescence spectra, temperature characteristics and reliability. The conventional yellow phosphor based on Y3Al5O12:Ce3+ has excellent performance as a single phosphor combined with a blue LED. More recently developed nitrido- or oxonitrido-silicates activated with Eu2+ are also promising materials showing green to red luminescence depending on a composition and high thermal and chemical stability. And yet, demands for specific application have been made clear and strong. This paper reviews the present status and challenging goals of phosphors in the next stage further to make progress in white LEDs.

  13. Jewish Wedding Traditions

    OpenAIRE

    ÜNAL, Asife

    2016-01-01

    The traditional Jewish wedding has so far unchanged for centuries in the basic elements, although each congregation has demonstrated little differences due to settled customs. The Jewish wedding traditions carries proper religious properties for the the sanctity of family unity which conduce to the continuation of the Jewish generation. The community attaches great importance to this united ceremony, combining the engagement (erusin/kiddushin) and the marriage (nisuin) which had been done sep...

  14. Traditional Indonesian dairy foods.

    Science.gov (United States)

    Surono, Ingrid S

    2015-01-01

    Indonesia is the largest archipelago blessed with one of the richest mega-biodiversities and also home to one of the most diverse cuisines and traditional fermented foods. There are 3 types of traditional dairy foods, namely the butter-like product minyak samin; yogurt-like product dadih; and cheese-like products dali or bagot in horbo, dangke, litsusu, and cologanti, which reflect the culture of dairy product consumption in Indonesia.

  15. New reversing freeform lens design method for LED uniform illumination with extended source and near field

    Science.gov (United States)

    Zhao, Zhili; Zhang, Honghai; Zheng, Huai; Liu, Sheng

    2018-03-01

    In light-emitting diode (LED) array illumination (e.g. LED backlighting), obtainment of high uniformity in the harsh condition of the large distance height ratio (DHR), extended source and near field is a key as well as challenging issue. In this study, we present a new reversing freeform lens design algorithm based on the illuminance distribution function (IDF) instead of the traditional light intensity distribution, which allows uniform LED illumination in the above mentioned harsh conditions. IDF of freeform lens can be obtained by the proposed mathematical method, considering the effects of large DHR, extended source and near field target at the same time. In order to prove the claims, a slim direct-lit LED backlighting with DHR equal to 4 is designed. In comparison with the traditional lenses, illuminance uniformity of LED backlighting with the new lens increases significantly from 0.45 to 0.84, and CV(RMSE) decreases dramatically from 0.24 to 0.03 in the harsh condition. Meanwhile, luminance uniformity of LED backlighting with the new lens is obtained as high as 0.92 at the condition of extended source and near field. This new method provides a practical and effective way to solve the problem of large DHR, extended source and near field for LED array illumination.

  16. LED module with high index lens

    Energy Technology Data Exchange (ETDEWEB)

    Bierhuizen, Serge J.; Wang, Nanze Patrick; Eng, Gregory W.; Sun, Decai; Wei, Yajun

    2017-09-05

    An array of housings with housing bodies and lenses is molded, or an array of housing bodies is molded and bonded with lenses to form an array of housings with housing bodies and lenses. Light-emitting diodes (LEDs) are attached to the housings in the array. An array of metal pads may be bonded to the back of the array or insert molded with the housing array to form bond pads on the back of the housings. The array is singulated to form individual LED modules.

  17. Intelligent styring af dynamisk LED belysning

    DEFF Research Database (Denmark)

    Thorseth, Anders; Corell, Dennis Dan; Hansen, Søren Stentoft

    Denne slutrapport giver en kort beskrivelse af arbejdet, der er udført af DTU Fotonik i projektet ”Intelligent styring af dynamisk LED belysning” støttet af EUDP. Arbejdet er udført i perioden 2011‐2012 i samarbejde med Lighten.......Denne slutrapport giver en kort beskrivelse af arbejdet, der er udført af DTU Fotonik i projektet ”Intelligent styring af dynamisk LED belysning” støttet af EUDP. Arbejdet er udført i perioden 2011‐2012 i samarbejde med Lighten....

  18. Final report LED solutions for public lighting; Eindrapportage LED oplossingen voor openbare verlichting

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-04-15

    This report examines if and how LED can be used for public lighting on a large scale. Pilot projects in 29 municipalities were assessed to test the usefulness of LED lighting. This final report provides answers to the questions that relate to the feasibility of the deployment of LED in public lighting and provides some practical pointers. [Dutch] Er is onderzocht of, en zo ja op welke wijze, LED grootschalig toegepast kan worden in de openbare verlichting (OVL). In 29 gemeenten in Nederland zijn proefprojecten geevalueerd om LED verlichting te toetsen op bruikbaarheid. Deze eindrapportage geeft antwoord op vragen die betrekking hebben op de haalbaarheid van de toepassing van LED binnen de OVL en geeft wat praktische aandachtspunten.

  19. Design of an oximeter based on LED-LED configuration and FPGA technology.

    Science.gov (United States)

    Stojanovic, Radovan; Karadaglic, Dejan

    2013-01-04

    A fully digital photoplethysmographic (PPG) sensor and actuator has been developed. The sensing circuit uses one Light Emitting Diode (LED) for emitting light into human tissue and one LED for detecting the reflectance light from human tissue. A Field Programmable Gate Array (FPGA) is used to control the LEDs and determine the PPG and Blood Oxygen Saturation (S(p)O(2)). The configurations with two LEDs and four LEDs are developed for measuring PPG signal and Blood Oxygen Saturation (S(p)O(2)). N-LEDs configuration is proposed for multichannel S(p)O(2) measurements. The approach resulted in better spectral sensitivity, increased and adjustable resolution, reduced noise, small size, low cost and low power consumption.

  20. Design of an Oximeter Based on LED-LED Configuration and FPGA Technology

    Directory of Open Access Journals (Sweden)

    Radovan Stojanovic

    2013-01-01

    Full Text Available A fully digital photoplethysmographic (PPG sensor and actuator has been developed. The sensing circuit uses one Light Emitting Diode (LED for emitting light into human tissue and one LED for detecting the reflectance light from human tissue. A Field Programmable Gate Array (FPGA is used to control the LEDs and determine the PPG and Blood Oxygen Saturation (SpO2. The configurations with two LEDs and four LEDs are developed for measuring PPG signal and Blood Oxygen Saturation (SpO2. N-LEDs configuration is proposed for multichannel SpO2 measurements. The approach resulted in better spectral sensitivity, increased and adjustable resolution, reduced noise, small size, low cost and low power consumption.

  1. LED structure with enhanced mirror reflectivity

    Science.gov (United States)

    Bergmann, Michael; Donofrio, Matthew; Heikman, Sten; Schneider, Kevin S; Haberern, Kevin W; Edmond, John A

    2014-04-01

    Embodiments of the present invention are generally related to LED chips having improved overall emission by reducing the light-absorbing effects of barrier layers adjacent mirror contacts. In one embodiment, a LED chip comprises one or more LEDs, with each LED having an active region, a first contact under the active region having a highly reflective mirror, and a barrier layer adjacent the mirror. The barrier layer is smaller than the mirror such that it does not extend beyond the periphery of the mirror. In another possible embodiment, an insulator is further provided, with the insulator adjacent the barrier layer and adjacent portions of the mirror not contacted by the active region or by the barrier layer. In yet another embodiment, a second contact is provided on the active region. In a further embodiment, the barrier layer is smaller than the mirror such that the periphery of the mirror is at least 40% free of the barrier layer, and the second contact is below the first contact and accessible from the bottom of the chip.

  2. LED Lighting in a Performing Arts Building

    Energy Technology Data Exchange (ETDEWEB)

    Miller, N. J.; Kaye, S. M. [Univ. of Florida, Gainesville, FL (United States); Coleman, P. M. [Univ. of Florida, Gainesville, FL (United States); Wilkerson, A. M.; Perrin, T. E.; Sullivan, G. P. [Efficiency Solutions, Inc., Richland, WA (United States)

    2014-07-31

    At the University of Florida in Gainesville, the DOE Solid-State Lighting GATEWAY program evaluated LED architectural and theatrical lighting in four academic/performance-related spaces within the Nadine McGuire Theatre + Dance Pavilion. Due to a wise choice of products and luminaire light distributions, the change brought significant quality improvements including improved controllability and color.

  3. Preliminary investigations of piezoelectric based LED luminary

    DEFF Research Database (Denmark)

    Nielsen, Dennis; Andersen, Michael A. E.; Meyer, Kaspar Sinding

    2011-01-01

    This paper presents a preliminary study of PT (Piezoelectric Transformer) based SMPS’s (Switch Mode Power Supplies) for LED luminary. The unique properties of PTs (efficiency, power density and EMI) make them highly suitable for this application. Power stage topologies, rectifiers circuits...

  4. NASA Ames UV-LED Poster Overview

    Science.gov (United States)

    Jaroux, Belgacem Amar

    2015-01-01

    UV-LED is a small satellite technology demonstration payload being flown on the Saudisat-4 spacecraft that is demonstrating non-contacting charge control of an isolated or floating mass using new solid-state ultra-violet light emitting diodes (UV-LEDs). Integrated to the rest of the spacecraft and launched on a Dnepr in June 19, 2014, the project is a collaboration between the NASA Ames Research Center (ARC), Stanford University, and King Abdulaziz City for Science and Technology (KACST). Beginning with its commissioning in December, 2015, the data collected by UV-LED have validated a novel method of charge control that will improve the performance of drag-free spacecraft allowing for concurrent science collection during charge management operations as well as reduce the mass, power and volume required while increasing lifetime and reliability of a charge management subsystem. UV-LED continues to operate, exploring new concepts in non-contacting charge control and collecting data crucial to understanding the lifetime of ultra-violet light emitting diodes in space. These improvements are crucial to the success of ground breaking missions such as LISA and BBO, and demonstrates the ability of low cost small satellite missions to provide technological advances that far exceed mission costs.

  5. Child-Led Enquiry in Primary Science

    Science.gov (United States)

    Dunlop, Lynda; Compton, Kirsty; Clarke, Linda; McKelvey-Martin, Valerie

    2015-01-01

    This research describes and evaluates the application of a child-led approach to scientific enquiry (the Community of Scientific Enquiry, CoSE) to children aged 8-11 (Key Stage 2) in Northern Ireland. Primary teachers were introduced to CoSE at a workshop and asked to evaluate its implementation with their class. Results from children (n = 364)…

  6. Aboriginal traditional knowledge - panel presentation

    International Nuclear Information System (INIS)

    Barnaby, J.; Duiven, M.; Garibaldi, A.; McGregor, D.; Straker, J.; Patton, P.

    2011-01-01

    Aboriginal peoples in Canada are playing a more active role in land use and resource management decisions around industrial development in their traditional territories and communities. Both indigenous and non-indigenous people are therefore increasing efforts to collaborate in decision-making and to effectively interweave Aboriginal Traditional Knowledge (ATK) and Western knowledge or science. Challenges exist, in part because non-Aboriginal people often find it difficult to define ATK and to understand the differences from Western perspectives. ATK is best defined as a holistic system that involves not only knowledge but principles of conduct and a strong relationship component. Research has focused on approaches to more easily bridge ATK and Western knowledge, through dialogue/negotiation and shared decision-making that is complementary to both. There are some examples of organizations and communities that have achieved success in this bridging of the two forms of knowledge. The Skeena Fisheries Commission (SFC) in British Columbia manages the fish resource in the Skeena Watershed and generates scientific research through links to ATK. The observations of indigenous people about apparent changes in the resource are subjected to scientific assessment, which has led to changes in how fish are caught, and in how and by whom data is collected. Traditional knowledge has also been incorporated into the reclamation of lands and species in Fort McKay, Alberta, an indigenous community whose traditional way of life has been significantly affected by development of the oil sands. New models have been developed to incorporate ATK into long-term planning for land use. This includes using ATK to develop a 50-to 60-year projection of probable future effects from development and to build strategies for achieving a 'desired future landscape.' To plan for post-mining land reclamation projects, another project makes use of cultural keystone species (CKS), through which

  7. Aboriginal traditional knowledge - panel presentation

    Energy Technology Data Exchange (ETDEWEB)

    Barnaby, J. [JB, Consultant, Paris (France); Duiven, M. [Skeena Fisheries Commission, Kispiox, BC (Canada); Garibaldi, A. [Integral Ecology Group, Ltd., Victoria, BC (Canada); McGregor, D. [Univ. of Toronto, Dept. of Geography and Aboriginal Studies, Toronto, ON (Canada); Straker, J. [Integral Ecology Group, Ltd., Victoria, BC (Canada); Patton, P. [Nuclear Waste Management Organization, Toronto, ON (Canada)

    2011-07-01

    Aboriginal peoples in Canada are playing a more active role in land use and resource management decisions around industrial development in their traditional territories and communities. Both indigenous and non-indigenous people are therefore increasing efforts to collaborate in decision-making and to effectively interweave Aboriginal Traditional Knowledge (ATK) and Western knowledge or science. Challenges exist, in part because non-Aboriginal people often find it difficult to define ATK and to understand the differences from Western perspectives. ATK is best defined as a holistic system that involves not only knowledge but principles of conduct and a strong relationship component. Research has focused on approaches to more easily bridge ATK and Western knowledge, through dialogue/negotiation and shared decision-making that is complementary to both. There are some examples of organizations and communities that have achieved success in this bridging of the two forms of knowledge. The Skeena Fisheries Commission (SFC) in British Columbia manages the fish resource in the Skeena Watershed and generates scientific research through links to ATK. The observations of indigenous people about apparent changes in the resource are subjected to scientific assessment, which has led to changes in how fish are caught, and in how and by whom data is collected. Traditional knowledge has also been incorporated into the reclamation of lands and species in Fort McKay, Alberta, an indigenous community whose traditional way of life has been significantly affected by development of the oil sands. New models have been developed to incorporate ATK into long-term planning for land use. This includes using ATK to develop a 50-to 60-year projection of probable future effects from development and to build strategies for achieving a 'desired future landscape.' To plan for post-mining land reclamation projects, another project makes use of cultural keystone species (CKS), through which

  8. LED light recycling using double prisms

    Science.gov (United States)

    Ouyang, George; Li, Kenneth

    2013-09-01

    A novel LED recycling scheme using double prisms is presented. Two identical triangular prisms with square bases, one cross-stacked on top of the other, are tight-fit into a mirrored light tunnel. The whole prism/light tunnel assembly is then mounted on top of a square LED source, whose emitting area is the same as that of the base plane of the said prism/light tunnel assembly. Each prism acts as a tapered-down light guide in one dimension, which selectively retro-reflects high angle light along that direction. The outer light tunnel serves as a mirrored wall that folds back any light that escapes outside the two prisms. For a given collection cone angle, the height of the two prisms is optimized using ASAP, a commercial ray-tracing software. Simulation and experimental results show promise in significantly increasing the brightness of the LED sources within the collection cone. Specifically for a 4x recycling ratio a 70% recycling gain in center illuminance has been achieved (i.e., illuminance measured in the forward direction). This scheme has advantages over previous recycling configurations due to its compactness and ease of mounting. For example, compared to Wavien's spherical reflector approach that has been previously published, the current recycling configuration is much smaller in size because instead of fitting a much larger mirrored reflector on top of the LED source, this time we're using a structure that has the same lateral dimensions as those of the LED source itself. Further improvement is also possible if optimization of various system parameters is carried out.

  9. Traditional Chinese and Thai medicine in a comparative perspective.

    Science.gov (United States)

    He, Ke

    2015-12-01

    The work presented in this paper compares traditional Chinese medicine and traditional Thai medicine, expounding on origins, academic thinking, theoretical system, diagnostic method and modern development. Based on a secondary analysis of available literature, the paper concentrates on two crucial historical developments: (1) the response to, and consequences of, the impact of the Western medicine; and (2) the revival of traditional medicine in these two countries and its prospects. From a comparative perspective, the analysis has led to the conclusion that the rise and fall of traditional medicine is an issue closely related with social and political issues; and the development of traditional medicines requires national policy and financial support from governments, human resource development, the improvement of service quality, and the dissemination of traditional medicine knowledge to the public. In addition, this paper also suggests deepening exchanges and cooperation between China and Thailand, strengthening cooperation between traditional medicine and medical tourism. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. KASTAMONU TRADITIONAL WOMEN CLOTHES

    Directory of Open Access Journals (Sweden)

    E.Elhan ÖZUS

    2015-08-01

    Full Text Available Clothing is a unique dressing style of a community, a period or a profession. In clothing there is social status and difference principle rather than fashion. In this context, the society created a clothing style in line with its own customs, traditions and social structure. One of the features separating societies from each other and indicating their cultural and social classes is the clothing style. As it is known, traditional Turkish clothes reflecting the characteristics of Turkish society is our most beautiful heritage from past to present. From this heritage there are several examples of women's clothes c arried to present. When these examples are examined, it is possible to see the taste, the way of understanding art, joy and the lifestyle of the history. These garments are also the documents outlining the taste and grace of Turkish people. In the present study, traditional Kastamonu women's clothing, that has an important place in traditional cultural clothes of Anatolia, is investigated . The method of the present research is primarily defined as the examination of the written sources. The study is complet ed with the observations and examinations made in Kastamonu. According to the findings of the study, traditional Kastamonu women's clothing are examined and adapted to todays’ clothing.

  11. Identifying the Principles of Traditional Iranian Architecture in the Light of Vastu Shastra, the Traditional Indian Wisdom

    Directory of Open Access Journals (Sweden)

    Ali Goodarzi

    2014-06-01

    Full Text Available Traditional Iranian houses have always been recognized as examples of 'good-design' in the context of Iranian Architecture according to many scholars. It is believed that their creation has been influenced by the systems of beliefs in the traditional Iranian society; an established system closely followed in their design process which has led to their phenomenal architectural design. The traditional houses of Kashan are excellent examples of such which have often been described as the finest examples of Traditional Iranian houses. However insufficient documentation of the design process of these architectural masterpieces has led to disputes among scholars in determining the exacct architectural system, behind their creation. The effect therefore is not only the inability in creating houses with the same quality in current architectural societies of Iran, but also their decay due to lack of attention and preservation. Historical studies point towards an influence of Indian Architectural system, Vastu Shastra, on the creation of traditional Iranian houses, which appears to be the earlier practice of house design within the Indo-Aryan communities. Using Vastu Shastra as a framework, the objective is to conduct case studies on 22 traditional houses of Kashan to identify the existence of a similar well-established system in Iran based on which all the traditional houses have been designed, and further to introduce it as the traditional architectural system in Iran. In this way the principles of traditional houses of Kashan can be identified in the light of Vastu Shastra, the traditional Indian wisdom.

  12. LED Lightbulbs as a Source of Electricity Saving in Buildings

    Directory of Open Access Journals (Sweden)

    Zeb Akhtar

    2016-01-01

    Full Text Available Today a number of renewable energy technologies are available for power generation, but fossil fuels are still providing a dominant share nevertheless. In order to decrease the electric bill and save our environment, energy conservation is always crucial. In this paper a very interesting idea is presented which is economically viable to reduce electricity usage in our buildings. An effort has been made to estimate the amount of energy that could be saved in the dormitory section of the IMOP building in Russia. Although there are many ways to reduce the consumption of electricity in this building but here the emphasis is on changing light bulbs inside the rooms, kitchen, toilet and bathroom of each apartment. The scope of the study is to figure out monthly electricity saving by replacing traditional light bulbs by LED light bulbs in the building under consideration. The total investment required and the payback period is also presented.

  13. Student-Led Engagement of Journal Article Authors in the Classroom Using Web-Based Videoconferencing

    Science.gov (United States)

    Stockman, Brian J.

    2015-01-01

    The learning environment described here uses Web-based videoconferencing technology to merge the traditional classroom journal article discussion with student-led interviews of journal article authors. Papers that describe recent applications of a given technique are selected, with the author engagement occurring at the end of a three or four week…

  14. CooLED - efficient LED bulbs with custrom optics - final report

    DEFF Research Database (Denmark)

    Wolff, Jesper; Corell, Dennis Dan; Dam-Hansen, Carsten

    Denne rapport indeholder en beskrivelse af arbejdet udført i og resultaterne af forsknings- og udviklingsprojektet EUDP 64012-0226, CooLED – en ny generation LED Lyskilde for det tidsløse high-end marked....

  15. Sustainable LED Fluorescent Light Replacement Technology

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2011-09-30

    Ilumisys and the National Center for Manufacturing Sciences (NCMS) partnered on a three-year project awarded by the United States (U.S.) Department of Energy (DOE), to quantify the impacts of LED lamps, incandescent lamps and fluorescent benchmark lamps over a product lifecycle – i.e. to develop a sustainable design and manufacturing strategy that addresses product manufacturing, use, recycling and disposal scenarios for LED-based lighting. Based on the knowledge gained from extensive product tear-down studies of fluorescent and screw-in lighting products, lifecycle assessment tools, and accelerated lifecycle testing protocols, an interactive Sustainable LED Design Guide has been developed to aid architectural and lighting designers and engineers in making design decisions that consider three important environmental impacts (greenhouse gas emissions, energy use and mercury emission) across all phases of the life of an LED lighting product. Critical information developed for the lifecycle analysis and product feature comparisons is the useful life of the lighting product as well as its performance. The Design Guide is available at www.ncms.org, and was developed based on operational and durability testing of a variety of lighting products including power consumption, light output, and useful life of a lamp in order to allow a more realistic comparison of lamp designs. This report describes the main project tasks, results and innovative features of the lifecycle assessment (LCA)-based design tools, and the key considerations driving the sustainable design of LED lighting systems. The Design Guide incorporates the following three novel features for efficiently evaluating LED lighting features in value-chains: Bill-of-Materials (BOM) Builder – Designers may import process data for each component and supply functional data for the product, including power, consumption, lumen output and expected useful life: Environmental Impact Review – Designs are comparable

  16. Low-Cost Illumination-Grade LEDs

    Energy Technology Data Exchange (ETDEWEB)

    Epler, John [Philips Lumileds Lighting Company LLC, San Jose, CA (United States)

    2013-08-31

    Solid State Lighting is a cost-effective, energy-conserving technology serving a rapidly expand- ing multi-billion dollar market. This program was designed to accelerate this lighting revolution by reducing the manufacturing cost of Illumination-Grade LEDs. The technical strategy was to investigate growth substrate alternatives to standard planar sapphire, select the most effective and compatible option, and demonstrate a significant increase in Lumen/$ with a marketable LED. The most obvious alternate substrate, silicon, was extensively studied in the first two years of the program. The superior thermal and mechanical properties of Si were expected to improve wavelength uniformity and hence color yield in the manufacture of high-power illumination- grade LEDs. However, improvements in efficiency and epitaxy uniformity on standard c-plane sapphire diminished the advantages of switching to Si. Furthermore, the cost of sapphire decreased significantly and the cost of processing Si devices using our thin film process was higher than expected. We concluded that GaN on Si was a viable technology but not a practical option for Philips Lumileds. Therefore in 2012 and 2013, we sought and received amendments which broadened the scope to include other substrates and extended the time of execution. Proprietary engineered substrates, off-axis (non-c-plane) sapphire, and c-plane patterned sapphire substrates (PSS) were all investigated in the final 18 months of this program. Excellent epitaxy quality was achieved on all three candidates; however we eliminated engineered substrates and non-c-plane sapphire because of their higher combined cost of substrate, device fabrication and packaging. Ultimately, by fabricating a flip-chip (FC) LED based upon c-plane PSS we attained a 42% reduction in LED manufacturing cost relative to our LUXEON Rebel product (Q1-2012). Combined with a flux gain from 85 to 102 Lm, the LUXEON Q delivered a 210% increase in Lm/$ over this time period. The

  17. Family traditions and generations.

    Science.gov (United States)

    Schneiderman, Gerald; Barrera, Maru

    2009-01-01

    Currently, traditional family values that have been passed down through generations appear to be at risk. This has significant implications for the stability and health of individuals, families, and communities. This article explores selected issues related to intergenerational transmission of family values and cultural beliefs, with particular reference to Western culture and values that are rooted in Jewish and Christian traditions. It also examines family values and parenting styles as they influence the developing perspective of children and the family's adaptation to a changing world.

  18. Construction traditions and Restoration

    Directory of Open Access Journals (Sweden)

    B. Paolo Torsello

    2010-12-01

    Full Text Available In view of the physical and material incompatibility of many restoration works performed in the past, in recent years there has arisen a debate about the wisdom of retrieving old building traditions for the restoration process with a simple mechanical interpretation. Professor Torsello dissects the concept of tradition as regards its relationship with experience, science, history and production to discover an order of problems that affect the structure of our knowledge and whose origin resides in the radical changes that characterise modernity.

  19. Healthier Traditional Food

    OpenAIRE

    Edward F. Millen

    2017-01-01

    The study of traditional food and healthy eating habits has been one of the fast growing areas. All humans, both men and women, require food for their survival. However, both men and women indulge in food as if it were their sole purpose of existence. Hence, eating disorders are common among men and women. Then media has played an effective role not only in establishing faulty standards for traditional healthy food but also it has highlighted the importance of healthy eating. It has brought t...

  20. Lifetime prediction of LED lighting systems considering thermal coupling between LED sources and drivers

    DEFF Research Database (Denmark)

    Alfarog, Azzarn Orner; Qu, Xiaohui; Wang, Huai

    2017-01-01

    The lifetime prediction of LED lighting system is important to guide the designers to fulfill the design specifications and to benchmark the cost-competitiveness of different lighting technologies. Currently, the lifetime of LED system is usually predicted from the source part and the driver part...... separately, and then the thermal design is also optimized independently. In practice, the LED source and driver are usually compacted in a single fixture. The heat dissipated from LED source and driver will be coupled together and affect the heat transfer performance, which may degrade the whole system...... and accelerate the failure. In this paper, a new thermal model concerning the thermal coupling is proposed with Finite Element Method (FEM) simulation for parameter acquirement. The proposed model has a better estimation of the thermal stresses of key components in the LED lamps and therefore an improved...

  1. LED i Københavns Kommunes gadebelysning

    DEFF Research Database (Denmark)

    Bülow, Katja

    2016-01-01

    Artiklen i denne udgivelse formidler resultatet af en undersøgelse, hvor de visuelle forhold i Københavns Kommunes gader undersøges som resultat af gadens belysning. Der lægges vægt på metoden bag undersøgelsen og på hvordan indførelsen af LED forandrer belysningen i gaderne.......Artiklen i denne udgivelse formidler resultatet af en undersøgelse, hvor de visuelle forhold i Københavns Kommunes gader undersøges som resultat af gadens belysning. Der lægges vægt på metoden bag undersøgelsen og på hvordan indførelsen af LED forandrer belysningen i gaderne....

  2. EVALUATING THE CULTURE-LED REGENERATION

    Directory of Open Access Journals (Sweden)

    D'Angelo Francesca

    2010-12-01

    Full Text Available The aim of the paper is to propose a new approach to urban planning, evaluating the culture-led regeneration processes. In the last few years, the cultural turn in urban planning played a central role in the urban studies. In this way we try to elaborate a more robust perspective interpreting the complex phenomenology emerging from the culture-led regeneration processes. Within the concept of complexity we discuss about the metabolic process that are the processes necessary to transform energy, material and information in goods and service functional to the complex urban system life. The approach that will be employed is the MuSIASEM that is based on several novel concept and an innovative methods never applied in this research field.

  3. Uniform LED illuminator for miniature displays

    Science.gov (United States)

    Medvedev, Vladimir; Pelka, David G.; Parkyn, William A.

    1998-10-01

    The Total Internally Reflecting (TIR) lens is a faceted structure composed of prismatic elements that collect a source's light over a much larger angular range than a conventional Fresnel lens. It has been successfully applied to the efficient collimation of light from incandescent and fluorescent lamps, and from light-emitting diodes (LEDs). A novel LED-powered collimating backlight is presented here, for uniformly illuminating 0.25'-diagonal miniature liquid- crystal displays, which are a burgeoning market for pagers, cellular phones, digital cameras, camcorders, and virtual- reality displays. The backlight lens consists of a central dual-asphere refracting section and an outer TIR section, properly curved with a curved exit face.

  4. Notes on LED Installations in Street Illumination

    Directory of Open Access Journals (Sweden)

    Elisabeta Spunei

    2014-09-01

    Full Text Available The paper presents a study made on choosing LED street lighting installations, such that the quality requirements for exterior artificial lighting are fulfilled. We analyze two types of LED street lighting installations from a technical point of view, together with lighting level and brightness values obtained during the measurements. Following on the field measurements, the lighting quality parameters are calculated, and, for the lighting installation with the best performance, optimal mounting suggestions are made. The optimal quality parameters are calculated by simulations using the Dialux software. The same software and the same light sources we also compute an optimal street lighting by determining the size of the installation that provides the best lighting parameter values.

  5. Optical design of a LED searchlight system

    Science.gov (United States)

    Gong, Chen; Xu, Haiping; Liang, Jinhua; Liu, Yunfei; Yuan, Zengquan

    2018-01-01

    A 1200m visible searchlight system is designed based on photometry and application of geometric optics. To generate intensity distribution of this relatively powerful light beam we propose to use a high power LED and several refractive optical elements, which are composed of two plane-convex lenses and a conventional Fresnel lens. Two plane-convex lenses enable refraction of the side rays from the LED to the front direction which incident on the Fresnel lens. Fresnel lens, in its turn, concentrate the light flux and provide a nearly collimated beam to meet the requirement of forming a well-illuminated area across the road in the far field. Simulation data shows that this searchlight allow generating an appropriate illumination distribution for the long range requirements. A proof-of-concept prototype producing acceptable illuminance is developed.

  6. Distributed dimming control for LED lighting.

    Science.gov (United States)

    Lee, Sang Hyun; Kwon, Jae Kyun

    2013-11-04

    This paper presents a distributed energy-saving lighting strategy for the arrangements of a lighting network consisting of a group of light-emitting diode (LED) lamps and users. LED lamps have a dimming support feature to meet the illuminance requirements imposed by individual users. Both groups interact with each other via visible light communication (VLC) or other wireless communication features. This work aims to identify a configuration of lamps leading to the maximal energy saving in adaptive and distributed ways. To this end, a distributed assignment strategy is developed based on a message-passing framework where only local interactions among lamps and users are allowed for calculations and exchanges of the information on their status. The simulation results show that the proposed algorithm outperforms other distributed algorithms in a range of indoor lighting configurations.

  7. Newly patented process enables low-cost solution for increasing white light spectrum of LEDs

    Science.gov (United States)

    Spanard, Jan-Marie

    2017-10-01

    A newly patented process for completing the spectral light array emitted by LED bulbs provides a low-cost method for producing better human centered lighting (HCL). This process uses non-luminescent colorant filters, filling out the jagged LED spectral emission into a full, white light array. While LED bulbs have the distinct economic advantages of using less energy, producing less heat and lasting years longer than traditional incandescent bulbs, the persistent metameric failure of LED bulbs has resulted in slower, and sometimes reluctant, adoption of LED lighting by the residential, retail and architectural markets. Adding missing wavelengths to LED generated bulbs via colorant filters increases the aesthetic appeal of the light by decreasing current levels of metameric failure, reducing the `flatness', `harshness', and `dullness' of LED generated light reported by consumers. LED phosphor-converted light can be successfully tuned to "whiter" white light with selective color filtering using permanent, durable transparent pigments. These transparent pigments are selectively applied in combination with existing manufacturing technologies and utilized as a final color-tuning step in bulb design. The quantity of emitted light chosen for color filtering can be adjusted from 1% to 100% of emitted light, creating a custom balance of light quantity with light quality. This invention recognizes that "better light" is frequently chosen over "more light" in the consumer marketplace.

  8. An Overview of LEDs' Effects on the Production of Bioactive Compounds and Crop Quality.

    Science.gov (United States)

    Hasan, Md Mohidul; Bashir, Tufail; Ghosh, Ritesh; Lee, Sun Keun; Bae, Hanhong

    2017-08-27

    Light-emitting diodes (LEDs) are characterized by their narrow-spectrum, non-thermal photon emission, greater longevity, and energy-saving characteristics, which are better than traditional light sources. LEDs thus hold the potential to revolutionize horticulture lighting technology for crop production, protection, and preservation. Exposure to different LED wavelengths can induce the synthesis of bioactive compounds and antioxidants, which in turn can improve the nutritional quality of horticultural crops. Similarly, LEDs increase the nutrient contents, reduce microbial contamination, and alter the ripening of postharvest fruits and vegetables. LED-treated agronomic products can be beneficial for human health due to their good nutrient value and high antioxidant properties. Besides that, the non-thermal properties of LEDs make them easy to use in closed-canopy or within-canopy lighting systems. Such configurations minimize electricity consumption by maintaining optimal incident photon fluxes. Interestingly, red, blue, and green LEDs can induce systemic acquired resistance in various plant species against fungal pathogens. Hence, when seasonal clouds restrict sunlight, LEDs can provide a controllable, alternative source of selected single or mixed wavelength photon source in greenhouse conditions.

  9. Lampu Pintar Berbasis LED Dengan Multi Sensor

    OpenAIRE

    Ramdan, Ade; Prajitno, Dicky Rianto; Herlan, Herlan; Gojali, Elli Ahmad

    2013-01-01

    In this paper, we propose a LED-based smart lamp prototype that integrated with sensor. The smart lamp use information of people and lighting confirmation, to turn on or turn off the lamp automatically. In addition, the sensor calculates and balances flash and ambient light exposure to decrease the light, so that can make energy efficiently in use. PIR (Passive Infrared Receiver) and Ultrasonic sensor is preferred to detect people condition in one place and LDR (Light Dependent Resistant) is ...

  10. Preliminary investigations of piezoelectric based LED luminary

    DEFF Research Database (Denmark)

    Nielsen, Dennis; Andersen, Michael A. E.; Meyer, Kaspar Sinding

    2011-01-01

    This paper presents a preliminary study of PT (Piezoelectric Transformer) based SMPS’s (Switch Mode Power Supplies) for LED luminary. The unique properties of PTs (efficiency, power density and EMI) make them highly suitable for this application. Power stage topologies, rectifiers circuits, modul....... The prototype constitutes a light source equivalent to the 40 W incandescent bulb. Experimental results shows, that the prototype are capable of ZVS and dimming (the later trough use of burst mode control)....

  11. UV LED lighting for automated crystal centring

    International Nuclear Information System (INIS)

    Chavas, Leonard M. G.; Yamada, Yusuke; Hiraki, Masahiko; Igarashi, Noriyuki; Matsugaki, Naohiro; Wakatsuki, Soichi

    2011-01-01

    A low-cost light-emitting diode (LED) UV source has been developed for facilitating macromolecular sample centring in the X-ray beam. A direct outcome of the exponential growth of macromolecular crystallography is the continuously increasing demand for synchrotron beam time, both from academic and industrial users. As more and more projects entail screening a profusion of sample crystals, fully automated procedures at every level of the experiments are being implemented at all synchrotron facilities. One of the major obstacles to achieving such automation lies in the sample recognition and centring in the X-ray beam. The capacity of UV light to specifically react with aromatic residues present in proteins or with DNA base pairs is at the basis of UV-assisted crystal centring. Although very efficient, a well known side effect of illuminating biological samples with strong UV sources is the damage induced on the irradiated samples. In the present study the effectiveness of a softer UV light for crystal centring by taking advantage of low-power light-emitting diode (LED) sources has been investigated. The use of UV LEDs represents a low-cost solution for crystal centring with high specificity

  12. Export-led Growth Hypothesis: Turkey Application

    Directory of Open Access Journals (Sweden)

    İsmail KÜÇÜKAKSOY

    2015-12-01

    Full Text Available This paper aims to investigate validity of “Export-led Growth Hypothesis” for Turkey using quarterly data in period from 2003:Q1 to 2015:Q1. Hypothesis argues that there is causality relationship from real export to real Gross Domestic Product (GDP. Johansen cointegration test, Gregory-Hansen cointegration test, Toda-Yamamoto causality test, Fully Modified Ordinary Least Squares (FMOLS, Canonical cointegrating regression (CCR and Dynamic ordinary least squares (DOLS methods were used in this study. Findings can be summarized as follows: a According to Johansen cointegration test there is no relationship among variables in the long-run whereas Gregory-Hansen cointegration test has determined relationship in the long-run; b According to Toda-Yamamoto causality test there is bidirectional causality between real export and real GDP. This finding proves the validity of “Export-led Growth Hypothesis” for Turkey; c According to FMOLS, CCR, DOLS methods a 1% increase in the real export increases the real GDP by 1.5195%, 1.5552%, 1.3171% respectively in the long-run. These methods prove the validity of “Export-led Growth Hypothesis” for Turkey.

  13. Noodles, traditionally and today

    Directory of Open Access Journals (Sweden)

    Na Zhang

    2016-09-01

    Full Text Available Chinese noodles originated in the Han dynasty, which has more than 4,000 years of history. There are many stories about the origin of noodles. To a certain extent, noodles also reflect the cultural traditions and customs of China, which essentially means “human nature” and “worldly common sense”. There are thousands of varieties of noodles in China, according to the classification of the shape of noodles, seasoning gravy, cooking craft, and so on. Many noodles have local characteristics. Noodles are accepted by people from all over the world. The industrial revolution and the development of the food industry realized the transition from a traditional handicraft industry to mass production using machinery. In addition, the invention of instant noodles and their mass production also greatly changed the noodle industry. In essence, noodles are a kind of cereal food, which is the main body of the traditional Chinese diet. It is the main source of energy for Chinese people and the most economical energy food. Adhering to the principle of “making cereal food the main food”, is to maintain our Chinese good diet tradition, which can avoid the disadvantages of a high energy, high fat, and low carbohydrate diet, and promote health. The importance of the status of noodles in the dietary structure of residents in our country and the health impact should not be ignored.

  14. Making Tradition Healthy

    Centers for Disease Control (CDC) Podcasts

    2007-11-01

    In this podcast, a Latina nutrition educator shows how a community worked with local farmers to grow produce traditionally enjoyed by Hispanic/Latinos.  Created: 11/1/2007 by National Diabetes Education Program (NDEP), a joint program of the Centers for Disease Control and Prevention and the National Institutes of Health.   Date Released: 11/10/2007.

  15. by traditional bonesetters.

    African Journals Online (AJOL)

    menace caused by them. All patients referred to the University College Hospital between 1996 and 2001 were included in this study. Only a few number of the patients have been selected just to illustrate the menace caused by the traditional bonesetters in so many African societies. The deformities, financial loss.

  16. Traditions of technology

    Energy Technology Data Exchange (ETDEWEB)

    Nandy, A.

    1979-01-01

    Modern technology, with about 300 years of history behind it, has become the dominant tradition by marginalizing the other traditions of technology in the West and in the rest of the world. Important roles have been played in this marginalization by the ideology of Englightenment, by the Industrial Revolution, and nineteenth and twentieth century colonialism. They have blurred the difference between science and technology, underwritten the mechanomorphic world-image and promoted the concept of a value-free, ethically unrestrained technology. However, the present crises of technological consciousness has brought to the fore alternative traditions of technology, not as ethnotechnologies from which a universal, secular, modern technology can draw lessons, but as a competing philosophies of universality which can provide correctives to the alienating, exploitative, and dehumanizing role of modern science and technology. An alternative ideology of science is needed for this as well as a new legitimacy for the traditional technosystems and their cultural environments. Such a legitimacy will have to be based on a different set of values relating to the man--nature and man--man relationships and a deeper understanding of the politics of technology in its cross-national and cross-cultural contexts.

  17. Maltese medical Pauline traditions

    OpenAIRE

    Savona-Ventura, Charles

    2010-01-01

    The advent of the apostle Paul and evangelist Luke to the Maltese Islands in 60 AD led to the development of a number of pseudo-historic and medical beliefs that apparently saw their rise around the 12th century and reached a climax during the 17-18th centuries when an indigenous materia medica known as terra sigillata melitensis was being prepared and exported overseas. This eventually fell into disrepute by the latter half of the 19th century.

  18. Challenging tradition in Nigeria.

    Science.gov (United States)

    Supriya, K E

    1991-01-01

    In Nigeria since 1987, the National Association of Nigeria Nurses and Midwives (NSNNM) has used traditional medial and traditional health care workers to curtail the practice of female circumcision. Other harmful traditions are being changed also, such as early marriage, taboos of pregnancy and childbirth, and scarification. 30,000 member of NANNM are involved in this effort to halt the harmful practices themselves and to change community opinion. The program involved national and state level workshops on harmful health consequences of traditional practices and instruction on how to conduct focus group discussions to assess women's beliefs and practices. The focus groups were found to be a particularly successful method of opening up discussion of taboo topics and expressing deep emotions. The response to the knowledge that circumcision was not necessary was rage and anger, which was channeled into advocacy roles or change in the practice. The result was the channeled into advocacy roles for change in the practice. The result was the development of books, leaflets and videos. One community group designed a dress with a decorative motif of tatoos and bodily cuts to symbolize circumcision and scarring. Plays and songs were written and performed. Artists provided models of female genitalia both before and after circumcision. The campaign has been successful in bringing this issue to the public attention in prominent ways, such a national television, health talk shows, and women;s magazines. One of the most important results of the effort has been the demonstration that culture and tradition can be changed from within, rather than from outside imposition of values and beliefs.

  19. Light out-coupling from LEDs by means of metal nanoparticles; Lichtauskopplung aus LEDs mittels Metallnanoteilchen

    Energy Technology Data Exchange (ETDEWEB)

    Goehler, Tino

    2010-12-17

    The external quantum efficiency of light-emitting diodes (LEDs) based on Al- GaAs/InGaAlP is limited by total internal reflection because of the high refractive index (typically between 3 and 4) of the semiconductor. Metal nanoparticles (MNP) deposited on the surface of the LED can be used as dipole scatterers in order to enhance the emission of the LED. In this thesis, first, single gold nanoparticles of various sizes deposited on such an LED were investigated. A clear enhancement is detected as long as the dipole plasmon resonance of the particle is at a shorter wavelength than the LED emission. If the plasmon resonance coincides with the LED emission or is at a larger wavelength, the enhancement turns into suppression. Numerical simulations indicate that this latter effect is mainly caused by the particle quadrupole resonance producing extra absorption. Arrays of MNPs can be produced by a special mask technique called ''Fischer pattern nanolithography'' and manipulated in shape and size by additional steps. Originally, the MNPs produced by this technique are triangular in shape and turn out to suppress the LED emission. After transformation of the particles to spheres, a clear enhancement was detected. Light that would otherwise remain trapped inside the substrate is coupled out by resonant plasmonic scattering. Investigations on analogous structures on a transparent high-index material (GaP) indicate a stronger coupling between the particles than expected on the basis of literature data. (orig.)

  20. Buurtzorg: nurse-led community care.

    Science.gov (United States)

    Monsen, Karen A; de Blok, Jos

    2013-01-01

    Buurtzorg is a nurse-led, nurse-run organization of self-managed teams that provide home care to patients in their neighborhoods. Championing humanity over bureaucracy, autonomous teams work with primary care providers, community supports, and family resources to bring patients to optimal functioning as quickly as possible. The award-winning organization grew out of a common sense approach based on principles of trust, autonomy, creativity, simplicity, and collaboration. These organizational principles translate into highly effective and efficient care, satisfied patients, and enthusiastic nurses. The model is being replicated worldwide, with teams starting in Minnesota, Sweden, Japan, and other countries.

  1. Wheat Under LED's (Light Emitting Diodes)

    Science.gov (United States)

    2004-01-01

    Astroculture is a suite of technologies used to produce and maintain a closed controlled environment for plant growth. The two most recent missions supported growth of potato, dwarf wheat, and mustard plants, and provided scientists with the first opportunity to conduct true plant research in space. Light emitting diodes have particular usefulness for plant growth lighting because they emit a much smaller amount of radiant heat than do conventional lighting sources and because they have potential of directing a higher percentage of the emitted light onto plants surfaces. Furthermore, the high output LED's have emissions in the 600-700 nm waveband, which is of highest efficiency for photosynthesis by plants.

  2. Someone Has Led This Child To Believe

    OpenAIRE

    Louise, Regina

    2015-01-01

    ABSTRACTSOMEONE HAS LED THIS CHILD TO BELIEVE is a true story and continuation of the best-selling memoir Somebody’s Someone. After 12 year-old Regina Louise, tired of being beaten, battles and escapes an illegal guardian; she jumps from a two-story window and runs to a local police station where she is taken into custody, locked in a holding cell, and delivered to the Edgar Children’s Shelter, in Martinez California. Regina is closed off about her parents, her past…until she meets Jeanne Ke...

  3. Moral Issues in Intelligence-led Policing

    DEFF Research Database (Denmark)

    The core baseline of Intelligence-led Policing is the aim of increasing efficiency and quality of police work, with a focus on crime analysis and intelligence methods as tools for informed and objective decisions both when conducting targeted, specialized operations and when setting strategic...... priorities. This book critically addresses the proliferation of intelligence logics within policing from a wide array of scholarly perspectives. It considers questions such as: •How are precautionary logics becoming increasingly central in the dominant policing strategies? •What kind of challenges...... and the blurred and confrontational lines that can be observed between prevention, intelligence and investigation in police work....

  4. Traditional preventive treatment options

    DEFF Research Database (Denmark)

    Longbottom, C; Ekstrand, K; Zero, D

    2009-01-01

    conventional operative care, and since controlling the caries process prior to first restoration is the key to breaking the repair cycle and improving care for patients, future research should address the shortcomings in the current level of supporting evidence for the various traditional preventive treatment......Preventive treatment options can be divided into primary, secondary and tertiary prevention techniques, which can involve patient- or professionally applied methods. These include: oral hygiene (instruction), pit and fissure sealants ('temporary' or 'permanent'), fluoride applications (patient...

  5. Heat Transfer Characteristics in High Power LED Packaging

    Directory of Open Access Journals (Sweden)

    Chi-Hung Chung

    2014-03-01

    Full Text Available This study uses the T3Ster transient thermal resistance measuring device to investigate the effects to heat transfer performances from different LED crystal grains, packaging methods and heat-sink substrates through the experimental method. The experimental parameters are six different types of LED modules that are made alternatively with the crystal grain structure, the die attach method and the carrying substrate. The crystal grain structure includes the lateral type, flip chip type and vertical type. The die attach method includes silver paste and the eutectic structure. The carrying substrates are aluminum oxide (Alumina and aluminum nitride (AIN ceramic substrates and metal core PCB (MCPCB. The experimental results show that, under the conditions of the same crystal grain and die attach method, the thermal resistance values for the AIN substrate and the Alumina substrate are 2.1K/W and 5.1K/W, respectively and the total thermal resistance values are 7.3K/W and 10.8K/W. Compared to the Alumina substrate, the AIN substrate can effectively lower the total thermal resistance value by 32.4%. This is because the heat transfer coefficient of the AIN substrate is higher than that of the Alumina substrate, thus effectively increasing its thermal conductivity. In addition, under the conditions of the same crystal grain and the same substrate, the packaging methods are using silver paste and the eutectic structure for die attach. Their thermal resistance values are 5.7K/W and 2.7K/W, respectively, with a variance of 3K/W. Comparisons of the crystal grain structure show that the thermal resistance for the flip chip type is lower than that of the traditional lateral type by 0.9K/W. This is because the light emitting layer of the flip chip crystal grain is closer to the heat-sink substrate, shortening the heat dissipation route, and thus lowering the thermal resistance value. For the total thermal resistance, the crystal grain structure has a lesser

  6. Sadum: Traditional and Contemporary

    Directory of Open Access Journals (Sweden)

    Ratna Panggabean

    2009-07-01

    Full Text Available Sadum is one of the traditional cloths of the Batak people in North Sumatra. It is woven on a back strap loom with supplementary weft technique. Sadum is a warp faced weaving made of cotton and beads woven into the cloth. Ritually it is used as a shoulder cloth, gifts exchanges, and in dances. It also bears the symbol of good tidings and blessings for the receiver. The cloth has change during times in technique, color, patterns, as well as in functions. But the use as a ritual cloth stays the same. The basic weaving techniques and equipments used to create it hasn’t change, but its material and added techniques has made this cloth become more rich in color, pattern, and texture. Most changes began when the Europeans came to Indonesia and introduced new material such as synthetic fibers and colors. In the 70s traditional cloth of Indonesia got its boost when the government declared batik as Indonesian national attire. This encourages other traditional weavings to develop into contemporary clothing. Later, new techniques and material were introduced to the Sadum weavings including embroidery, silk and golden threads which were never used before.

  7. An investigation on LED customer’ behavior

    Directory of Open Access Journals (Sweden)

    Samaneh Sadat Khoramgah

    2013-03-01

    Full Text Available The recent advances in technology have created a challenge for customer on purchasing electronic devises since the cycle of media production such as TV, Mobile devices, etc. are getting short and people need to replace them by new products. The recent emerge of Light Emitting Diode (LED television has attracted many people and there is a concern to study the impact of important factors on customer behavior in this business. This paper presents an empirical study to study the effects of six variables including customer perception, motivation, cognitive learning, attitude, information and price on customer behavior for LED televisions produced by an Iranian firm in Tehran, Iran. The study designs a questionnaire consists of 27 questions and distributes it among some people who are potential customers of this product. We use multiple regression analysis to study the behavior of different factors on customer behavior. The results of our survey indicate that cognitive learning had the most influencing impact (0.22 on customer behavior followed by price (0.219, motivation (0.203, attitude (0.193, information (0.183 and perception (0.145.

  8. UV LED lighting for automated crystal centring.

    Science.gov (United States)

    Chavas, Leonard M G; Yamada, Yusuke; Hiraki, Masahiko; Igarashi, Noriyuki; Matsugaki, Naohiro; Wakatsuki, Soichi

    2011-01-01

    A direct outcome of the exponential growth of macromolecular crystallography is the continuously increasing demand for synchrotron beam time, both from academic and industrial users. As more and more projects entail screening a profusion of sample crystals, fully automated procedures at every level of the experiments are being implemented at all synchrotron facilities. One of the major obstacles to achieving such automation lies in the sample recognition and centring in the X-ray beam. The capacity of UV light to specifically react with aromatic residues present in proteins or with DNA base pairs is at the basis of UV-assisted crystal centring. Although very efficient, a well known side effect of illuminating biological samples with strong UV sources is the damage induced on the irradiated samples. In the present study the effectiveness of a softer UV light for crystal centring by taking advantage of low-power light-emitting diode (LED) sources has been investigated. The use of UV LEDs represents a low-cost solution for crystal centring with high specificity.

  9. Studying Light Color using White LED Lighting

    Science.gov (United States)

    Yamagishi, Misako; Yamaba, Kazuo; Nagata, Manori; Kubo, Chiho; Nokura, Kunihiro

    Recently, white Light Emitting Diodes (LEDs) are receiving attention worldwide as new lighting devices. This study examined effects of a lighting application on performance using white LEDs. The light color—the correlated color temperature (CCT) —was assessed. It affected to psychological states and physiological conditions. Three CCT conditions were respectively set for the experiment: 2500 K, 5000 K, and 8200 K. In all, 20 younger subjects (20-30 years old), 15 middle-aged to elderly subjects (45-60 years old) and 12 elderly subjects (over 65 years-old) participated. They were presented a Numerical Verification (NV) task for performance measurement. The psychological states on performance were evaluated using the lighting assessment questionnaire. The physiological conditions were recorded using an electrocardiograph. Results show that the effects of CCT differ among age groups. Especially, the performance of younger subjects might differ from CCT conditions; elderly subjects are affected by CCT condition because of their visual acuity or response to contrast of objects.

  10. The improvement of photocatalytic processes: Design of a photoreactor using high-power LEDs

    Directory of Open Access Journals (Sweden)

    Marzieh Khademalrasool

    2016-09-01

    Full Text Available This paper is an attempt to survey the benefits of a well-designed photoreactor containing just 6 ultraviolet (UV high power light emitting diodes (HPLEDs; the power and wavelength of each UV HPLED are 1 W and 365 nm, respectively, the latter being an efficient source for photocatalytic studies. Although the experiment with the 365-nm LEDs is reported here, other LEDs were predicted for conducting similar experiments including green photocatalytic ones. We installed diodes with respect to the luminescence intensity distribution curves (LIDCs or intensity patterns. Then, in order to compare the efficiency of the UV-HPLEDs of the HP-LED photoreactor (HPLED-PhR with that of traditional UV lamps which are extensively used in photocatalytic processes, a set of UV HPLEDs was designed and made up. Next, the performance of HPLED-PhR was compared with that of a traditional fluorescent lamp photoreactor (FL-PhR. As a typical photocatalytic experiment, Zinc Oxide (ZnO nanoparticles were synthesized via co-precipitation method and used as photocatalyst for purification of water polluted with the reactive blue dye (RB, under UV irradiation in two photoreactors. The results showed that the rate of photocatalytic reaction under the UV-LEDs was two times greater than the rate under the traditional fluorescent UV lamps, while both electrical power consumption and manufacturing cost of the HPLED-PhR were less than a quarter of them for the FL-PhR.

  11. Design and Manufacture of a Novel LED Table Lamp with Flower Decoration

    Directory of Open Access Journals (Sweden)

    Tzer-Ming Jeng

    2014-08-01

    Full Text Available This work involved the design and manufacture of a novel LED table lamp that provides for flower decoration. It is a combination of a normal LED table lamp and attachments holding flower arrangement frogs. In this application the frogs, as used for traditional flower arrangements, became heat sinks for the LED units. They are made of an aluminum alloy to give good heat transfer and dissipation. In any case since they are fixed to the unit they do not need to be very heavy. The design features of this novel flower-arrangement LED table lamp are: (1 the use of a light aluminum alloy flower decoration frog as a heat sink which gives both high heat dissipation and allows decorative flower arrangement; (2 the installation of LED lamps at three points of the same plate above a cylinder covered with a glass lampshade to achieve a beautiful effect; (3 to provide three different lighting modes for reading, use as a night light and for flower decoration. This novel LED table lamp meets all the energy-saving and environmental protection requirements. It has commercial potential in the market for LED lamps.

  12. Are nurse-led chemotherapy clinics really nurse-led? An ethnographic study.

    Science.gov (United States)

    Farrell, Carole; Walshe, Catherine; Molassiotis, Alex

    2017-04-01

    The number of patients requiring ambulatory chemotherapy is increasing year on year, creating problems with capacity in outpatient clinics and chemotherapy units. Although nurse-led chemotherapy clinics have been set up to address this, there is a lack of evaluation of their effectiveness. Despite a rapid expansion in the development of nursing roles and responsibilities in oncology, there is little understanding of the operational aspects of nurses' roles in nurse-led clinics. To explore nurses' roles within nurse-led chemotherapy clinics. A focused ethnographic study of nurses' roles in nurse-led chemotherapy clinics, including semi-structured interviews with nurses. Four chemotherapy units/cancer centres in the UK PARTICIPANTS: Purposive sampling was used to select four cancer centres/units in different geographical areas within the UK operating nurse-led chemotherapy clinics. Participants were 13 nurses working within nurse-led chemotherapy clinics at the chosen locations. Non-participant observation of nurse-led chemotherapy clinics, semi-structured interviews with nurse participants, review of clinic protocols and associated documentation. 61 nurse-patient consultations were observed with 13 nurses; of these 13, interviews were conducted with 11 nurses. Despite similarities in clinical skills training and prescribing, there were great disparities between clinics run by chemotherapy nurses and those run by advanced nurse practitioners. This included the number of patients seen within each clinic, operational aspects, nurses' autonomy, scope of practice and clinical decision-making abilities. The differences highlighted four different levels of nurse-led chemotherapy clinics, based on nurses' autonomy and scope of clinical practice. However, this was heavily influenced by medical consultants. Several nurses perceived they were undertaking holistic assessments, however they were using medical models/consultation styles, indicating medicalization of nurses' roles

  13. In the Dirac tradition

    International Nuclear Information System (INIS)

    Anon.

    1988-01-01

    It was Paul Dirac who cast quantum mechanics into the form we now use, and many generations of theoreticians openly acknowledge his influence on their thinking. When Dirac died in 1984, St. John's College, Cambridge, his base for most of his lifetime, instituted an annual lecture in his memory at Cambridge. The first lecture, in 1986, attracted two heavyweights - Richard Feynman and Steven Weinberg. Far from using the lectures as a platform for their own work, in the Dirac tradition they presented stimulating material on deep underlying questions

  14. LED--panacea or marketing hype?

    Science.gov (United States)

    Baillie, Jonathan

    2012-02-01

    With energy efficiency and carbon reduction, and the importance of a relaxing, therapeutic patient environment, ever more in the spotlight, LED lighting's proponents claim the technology offers healthcare estates personnel many of the answers on both fronts. However some observers believe its benefits are being over-sold, often to the detriment of other high-performing types of more 'conventional lighting', and to a sometimes uninitiated audience too easily swayed by slick sales patter. HEJ editor Jonathan Baillie spoke to one highly experienced lighting professional, Nicholas Bukorović, a former employee of Thorn, Cooper, and Thorlux Lighting, and the principal author of the last CIBSE/Society of Light and Lighting (SLL) Guide LG2 on healthcare lighting, to seek some expert illumination.

  15. Switched-capacitor isolated LED driver

    Science.gov (United States)

    Sanders, Seth R.; Kline, Mitchell

    2016-03-22

    A switched-capacitor voltage converter which is particularly well-suited for receiving a line voltage from which to drive current through a series of light emitting diodes (LEDs). Input voltage is rectified in a multi-level rectifier network having switched capacitors in an ascending-bank configuration for passing voltages in uniform steps between zero volts up to full received voltage V.sub.DC. A regulator section, operating on V.sub.DC, comprises switched-capacitor stages of H-bridge switching and flying capacitors. A current controlled oscillator drives the states of the switched-capacitor stages and changes its frequency to maintain a constant current to the load. Embodiments are described for isolating the load from the mains, utilizing an LC tank circuit or a multi-primary-winding transformer.

  16. Resident-Led Palliative Care Education Project.

    Science.gov (United States)

    Karlen, Naomi; Cruz, Brian; Leigh, A E

    2016-04-01

    Despite the growth of palliative medicine, 39% of hospitals do not have palliative care teams for consultation or to provide resident education. We examined the impact of resident-led education in palliative care principles on attitudes toward and comfort with palliative medicine and end-of-life care among internal medicine residents. An educational module designed by the authors was presented to other internal medicine residents in the program. Pre- and post-intervention survey data measuring residents' agreement with various statements regarding palliative medicine and end-of-life care were analyzed. Residents' agreement with various statements regarding palliative medicine and end-of-life care on a 5-point Likert scale was analyzed. Following the intervention, participants reported improved comfort with general knowledge of palliative medicine (p palliative care and end-of-life care (p curriculum in palliative medicine can improve resident comfort within this still-under-represented area of medicine.

  17. Parent-led or baby-led? Associations between complementary feeding practices and health-related behaviours in a survey of New Zealand families.

    Science.gov (United States)

    Cameron, Sonya L; Taylor, Rachael W; Heath, Anne-Louise M

    2013-12-09

    To determine feeding practices and selected health-related behaviours in New Zealand families following a 'baby-led' or more traditional 'parent-led' method for introducing complementary foods. 199 mothers completed an online survey about introducing complementary foods to their infant. Participants were classified into one of four groups: 'adherent baby-led weaning (BLW)', the infant mostly or entirely fed themselves at 6-7 months; 'self-identified BLW', mothers reported following BLW at 6-7 months but were using spoon-feeding at least half the time; 'parent-led feeding', the mother reported not having tried BLW; and 'unclassified method', the mother reported they were not following BLW at 6-7 months but reported the infant mostly or entirely fed themselves at 6-7 months. 8% were following 'adherent BLW', 21% 'self-identified BLW' and 0% were following the 'unclassified method'. Compared with 'self-identified BLW' and 'parent-led feeding', a higher proportion of the 'adherent BLW' met the WHO recommendations to exclusively breastfeed for 6 months and to introduce complementary foods at 6 months. The 'adherent BLW' group was more likely to have family foods (p=0.018), and less likely (p=0.002) to have commercially prepared baby food. Both BLW groups were more likely to share meals with the family compared with 'parent-led feeding'. In contrast to 'self-identified BLW' and 'parent-led feeding', the 'adherent BLW' group did not offer iron-fortified cereal as a first food. This study suggests that although many parents consider they follow BLW, a very few are following it strictly. The extent to which BLW was followed was associated with potential benefits (eg, sharing family meals) and risks (eg, low iron first foods) highlighting the importance for health professionals and researchers of accurately determining the extent of adherence to BLW.

  18. Open LED Illuminator: A Simple and Inexpensive LED Illuminator for Fast Multicolor Particle Tracking in Neurons.

    Science.gov (United States)

    Bosse, Jens B; Tanneti, Nikhila S; Hogue, Ian B; Enquist, Lynn W

    2015-01-01

    Dual-color live cell fluorescence microscopy of fast intracellular trafficking processes, such as axonal transport, requires rapid switching of illumination channels. Typical broad-spectrum sources necessitate the use of mechanical filter switching, which introduces delays between acquisition of different fluorescence channels, impeding the interpretation and quantification of highly dynamic processes. Light Emitting Diodes (LEDs), however, allow modulation of excitation light in microseconds. Here we provide a step-by-step protocol to enable any scientist to build a research-grade LED illuminator for live cell microscopy, even without prior experience with electronics or optics. We quantify and compare components, discuss our design considerations, and demonstrate the performance of our LED illuminator by imaging axonal transport of herpes virus particles with high temporal resolution.

  19. Open LED Illuminator: A Simple and Inexpensive LED Illuminator for Fast Multicolor Particle Tracking in Neurons

    Science.gov (United States)

    Bosse, Jens B.; Tanneti, Nikhila S.; Hogue, Ian B.; Enquist, Lynn W.

    2015-01-01

    Dual-color live cell fluorescence microscopy of fast intracellular trafficking processes, such as axonal transport, requires rapid switching of illumination channels. Typical broad-spectrum sources necessitate the use of mechanical filter switching, which introduces delays between acquisition of different fluorescence channels, impeding the interpretation and quantification of highly dynamic processes. Light Emitting Diodes (LEDs), however, allow modulation of excitation light in microseconds. Here we provide a step-by-step protocol to enable any scientist to build a research-grade LED illuminator for live cell microscopy, even without prior experience with electronics or optics. We quantify and compare components, discuss our design considerations, and demonstrate the performance of our LED illuminator by imaging axonal transport of herpes virus particles with high temporal resolution. PMID:26600461

  20. Open LED Illuminator: A Simple and Inexpensive LED Illuminator for Fast Multicolor Particle Tracking in Neurons.

    Directory of Open Access Journals (Sweden)

    Jens B Bosse

    Full Text Available Dual-color live cell fluorescence microscopy of fast intracellular trafficking processes, such as axonal transport, requires rapid switching of illumination channels. Typical broad-spectrum sources necessitate the use of mechanical filter switching, which introduces delays between acquisition of different fluorescence channels, impeding the interpretation and quantification of highly dynamic processes. Light Emitting Diodes (LEDs, however, allow modulation of excitation light in microseconds. Here we provide a step-by-step protocol to enable any scientist to build a research-grade LED illuminator for live cell microscopy, even without prior experience with electronics or optics. We quantify and compare components, discuss our design considerations, and demonstrate the performance of our LED illuminator by imaging axonal transport of herpes virus particles with high temporal resolution.

  1. Analysis of Student Performance in Peer Led Undergraduate Supplements

    Science.gov (United States)

    Gardner, Linda M.

    Foundations of Chemistry courses at the University of Kansas have traditionally accommodated nearly 1,000 individual students every year with a single course in a large lecture hall. To develop a more student-centered learning atmosphere, Peer Led Undergraduate Supplements (PLUS) were introduced to assist students, starting in the spring of 2010. PLUS was derived from the more well-known Peer-Led Team Learning with modifications to meet the specific needs of the university and the students. The yearlong investigation of PLUS Chemistry began in the fall of 2012 to allow for adequate development of materials and training of peer leaders. We examined the impact of academic achievement for students who attended PLUS sessions while controlling for high school GPA, math ACT scores, credit hours earned in high school, completion of calculus, gender, and those aspiring to be pharmacists (i.e., pre-pharmacy students). In a least linear squares multiple regression, PLUS participants performed on average one percent higher on exam scores for Chemistry 184 and four tenths of a percent on Chemistry 188 for each PLUS session attended. Pre-pharmacy students moderated the effect of PLUS attendance on chemistry achievement, ultimately negating any relative gain associated by attending PLUS sessions. Evidence of gender difference was demonstrated in the Chemistry 188 model, indicating females experience a greater benefit from PLUS sessions. Additionally, an item analysis studied the relationship between PLUS material to individual items on exams. The research discovered that students who attended PLUS session, answered the items correctly 10 to 20 percent more than their comparison group for PLUS interrelated items and no difference to 10 percent for non-PLUS related items. In summary, PLUS has a positive effect on exam performance in introductory chemistry courses at the University of Kansas.

  2. Correction of Severe Traditional Medication-induced Lower Lid ...

    African Journals Online (AJOL)

    Setting: The correction of the lower lid tarsal ectropion was carried out at the Rachel Eye Center in Abuja, Nigeria. Result: After conservative intervention failed, a free preauricular skin graft of the floppy ectropion, led to a stable correction. Conclusions: Harmful traditional eye medication continues to be a problem in the ...

  3. Re-Creating Awareness of Traditional Leafy Vegetables in ...

    African Journals Online (AJOL)

    Research and extension in South Africa has been labelling traditional leafy vegetables as weeds since the 1960s when they started encouraging households to produce food seen in the shops. This negative perception has led to an unwillingness to use and conserve these 'poverty foods', as many community members ...

  4. POWERED LED LIGHTING SUPPLIED FROM PV CELLS

    Directory of Open Access Journals (Sweden)

    Tirshu M.

    2011-12-01

    Full Text Available The paper deals with practical realization of efficient lighting system based on LED’s of 80W total power mounted on corridor ceiling total length of which is 120m and substitutes existing traditional lighting system consisting of 29 lighting blocks with 4 fluorescent lamps each of them and summary power 2088W. Realized lighting system is supplied from two photovoltaic panels of power 170W. Generated energy by PV cells is accumulated in two accumulators of 75Ah capacity and from battery by means of specialized convertor is applied to lighting system. Additionally, paper present data measured by digital weather station (solar radiation and UV index, which is mounted near of PV cells and comparative analyze of solar energy with real energy generated by PV cells is done. Measured parameters by digital weather station are stored by computer in on-line mode.

  5. LED Virtual Simulation based on Web3D

    OpenAIRE

    Lilan Liu; Liu Han; Zhiqi Lin; Manping Li; Tao Yu

    2014-01-01

    Regarding to the high price and low market popularity of current LED indoor lighting products, a LED indoor lighting platform is proposed based on Web3D technology. The internet virtual reality technology is integrated and applied into the LED collaborative e-commerce website with Virtools. According to the characteristics of the LED indoor lighting products, this paper introduced the method to build encapsulated model and three characteristics of LED lighting: geometrical, optical and behavi...

  6. Non-traditional inheritance

    International Nuclear Information System (INIS)

    Hall, J.G.

    1992-01-01

    In the last few years, several non-traditional forms of inheritance have been recognized. These include mosaicism, cytoplasmic inheritance, uniparental disomy, imprinting, amplification/anticipation, and somatic recombination. Genomic imprinting (GI) is the dependence of the phenotype on the sex of the transmitting parent. GI in humans seems to involve growth, behaviour, and survival in utero. The detailed mechanism of genomic imprinting is not known, but it seems that some process is involved in turning a gene off; this probably involves two genes, one of which produces a product that turns a gene off, and the gene that is itself turned off. The process of imprinting (turning off) may be associated with methylation. Erasure of imprinting can occur, and seems to be associated with meiosis. 10 refs

  7. Experiencing LED: Lighting: New Form and Experiential Qualities Emerging in Lighting Systems using LED

    DEFF Research Database (Denmark)

    Petersen, Kjell Yngve; Kristensen, Ole; Søndergaard, Karin

    2012-01-01

    The project investigates what new forms and qualities of light emerge from technologies such as LED, with a particular focus on basic form qualities and parameters. Existing linear functional understandings of the relation between light source, light flow, reflection and visibility is challenged ...... by relational understandings, where the materiality and visibility of the light emerge through mutual influences between several adaptive and transformative elements....

  8. LED street lighting evaluation -- phase II : LED specification and life-cycle cost analysis.

    Science.gov (United States)

    2015-01-01

    Phase II of this study focused on developing a draft specification for LED luminaires to be used by IDOT : and a life-cycle cost analysis (LCCA) tool for solid state lighting technologies. The team also researched the : latest developments related to...

  9. Baby-led Weaning: A Preliminary Investigation.

    Science.gov (United States)

    D'Andrea, Elisa; Jenkins, Kielyn; Mathews, Maria; Roebothan, Barbara

    2016-06-01

    To date, baby-led weaning (BLW) has not been examined in a Canadian population. This research investigated common BLW practices and compared associated knowledge and perceptions of practicing mothers and health care professionals (HCPs). Sixty-five mothers practicing BLW and 33 HCPs were surveyed using 2 online questionnaires. Mothers were recruited through the Newfoundland and Labrador BLW Facebook page and HCPs via email at 2 regional health authorities. Mothers described BLW in terms of food shape and consistency (whole, solid); however, in practice, some mothers offered puréed foods such as infant cereals. More HCPs than mothers indicated choking, inadequate energy, and iron intake as concerns. Mothers relied on the Facebook page over HCPs for BLW information and support. Although all practicing mothers would recommend BLW to others, less than half (48.5%) of HCPs would support it in their practice. Mothers following BLW vary greatly in their experiences and adherence to BLW. They view the practice and its disadvantages very differently than HCPs. Although most HCPs were aware of BLW, few were familiar with specific practices. HCPs may benefit from a greater understanding of BLW to provide guidance to the growing number of mothers following this practice.

  10. Led Astray by Hemoglobin A1c

    Directory of Open Access Journals (Sweden)

    Jean Chen MD

    2016-01-01

    Full Text Available Hemoglobin A1c (A1c is used frequently to diagnose and treat diabetes mellitus. Therefore, it is important be aware of factors that may interfere with the accuracy of A1c measurements. This is a case of a rare hemoglobin variant that falsely elevated a nondiabetic patient’s A1c level and led to a misdiagnosis of diabetes. A 67-year-old male presented to endocrine clinic for further management after he was diagnosed with diabetes based on an elevated A1c of 10.7%, which is approximately equivalent to an average blood glucose of 260 mg/dL. Multiple repeat A1c levels remained >10%, but his home fasting and random glucose monitoring ranged from 92 to 130 mg/dL. Hemoglobin electrophoresis and subsequent genetic analysis diagnosed the patient with hemoglobin Wayne, a rare hemoglobin variant. This variant falsely elevates A1c levels when A1c is measured using cation-exchange high-performance liquid chromatography. When the boronate affinity method was applied instead, the patient’s A1c level was actually 4.7%. Though hemoglobin Wayne is clinically silent, this patient was erroneously diagnosed with diabetes and started on an antiglycemic medication. Due to this misdiagnosis, the patient was at risk of escalation in his “diabetes management” and hypoglycemia. Therefore, it is important that providers are aware of factors that may result in hemoglobin A1c inaccuracy including hemoglobin variants.

  11. Assessing the colour quality of LED sources

    DEFF Research Database (Denmark)

    Jost-Boissard, S.; Avouac, P.; Fontoynont, Marc

    2015-01-01

    The CIE General Colour Rendering Index is currently the criterion used to describe and measure the colour-rendering properties of light sources. But over the past years, there has been increasing evidence of its limitations particularly its ability to predict the perceived colour quality of light...... but also with a preference index or a memory index calculated without blue and purple hues. A very low correlation was found between appreciation and naturalness indicating that colour quality needs more than one metric to describe subjective aspects.......The CIE General Colour Rendering Index is currently the criterion used to describe and measure the colour-rendering properties of light sources. But over the past years, there has been increasing evidence of its limitations particularly its ability to predict the perceived colour quality of light...... sources and especially some LEDs. In this paper, several aspects of perceived colour quality are investigated using a side-by-side paired comparison method, and the following criteria: naturalness of fruits and vegetables, colourfulness of the Macbeth Color Checker chart, visual appreciation...

  12. Blue LED irradiation to hydration of skin

    Science.gov (United States)

    Menezes, Priscila F. C.; Requena, Michelle B.; Lizarelli, Rosane F., Z.; Bagnato, Vanderlei S.

    2015-06-01

    Blue LED system irradiation shows many important properties on skin as: bacterial decontamination, degradation of endogenous skin chromophores and biostimulation. In this clinical study we prove that the blue light improves the skin hydration. In the literature none authors reports this biological property on skin. Then this study aims to discuss the role of blue light in the skin hydration. Twenty patients were selected to this study with age between 25-35 years old and phototype I, II and III. A defined area from forearm was pre determined (A = 4.0 cm2). The study was randomized in two treatment groups using one blue light device (power of 5.3mW and irradiance of 10.8mW/cm2). The first treatment group was irradiated with 3J/cm2 (277seconds) and the second with 6J/cm2 (555 seconds). The skin hydration evaluations were done using a corneometer. The measurements were collected in 7, 14, 21 and 30 days, during the treatment. Statistical test of ANOVA, Tukey and T-Student were applied considering 5% of significance. In conclusion, both doses were able to improve the skin hydration; however, 6J/cm2 has kept this hydration for 30 days.

  13. Visible light communication based vehicle positioning using LED street light and rolling shutter CMOS sensors

    Science.gov (United States)

    Do, Trong Hop; Yoo, Myungsik

    2018-01-01

    This paper proposes a vehicle positioning system using LED street lights and two rolling shutter CMOS sensor cameras. In this system, identification codes for the LED street lights are transmitted to camera-equipped vehicles through a visible light communication (VLC) channel. Given that the camera parameters are known, the positions of the vehicles are determined based on the geometric relationship between the coordinates of the LEDs in the images and their real world coordinates, which are obtained through the LED identification codes. The main contributions of the paper are twofold. First, the collinear arrangement of the LED street lights makes traditional camera-based positioning algorithms fail to determine the position of the vehicles. In this paper, an algorithm is proposed to fuse data received from the two cameras attached to the vehicles in order to solve the collinearity problem of the LEDs. Second, the rolling shutter mechanism of the CMOS sensors combined with the movement of the vehicles creates image artifacts that may severely degrade the positioning accuracy. This paper also proposes a method to compensate for the rolling shutter artifact, and a high positioning accuracy can be achieved even when the vehicle is moving at high speeds. The performance of the proposed positioning system corresponding to different system parameters is examined by conducting Matlab simulations. Small-scale experiments are also conducted to study the performance of the proposed algorithm in real applications.

  14. Development of Local-Economic-Development Small and Medium Industries (Led-Sme In East Java

    Directory of Open Access Journals (Sweden)

    Rachmad Hidayat

    2013-04-01

    Full Text Available This paper presents the effects of Indonesian government’s developmental efforts of assistance and training performed  on the growth of LED-SME business units and business performance. Both parameters of the government’s assistance and training were used to analyze the impact to the  growth and performance of business unit. To achieve a comprehensive result, samples acquired in this research were about 190 entrepreneurs and managers of LED-SME from East Java. Based on the parameters above, there are five hypotheses made to prove the relationship of the assistance and training to the growth and performance of business units. The structural equation modeling (SEM was carried out to test the hypotheses. The results have shown that the government’s developmental efforts through both assistance and training for the LED-SME were capable on increasing growth and performance of business units. On the other hand, government’s developmental efforts through only trainings were incapable of directly affecting growth of LED-SME business units and performance. To improve the business unit and performance, the government needs to implement developmental principles of LED-SME with the basis of utilizing local natural resources and also the communities of LED-SME as main suppliers for their local markets. In addition, preservation and development of local cultural and traditional arts also need to be the government’s main concern. 

  15. Hybrid sunlight/LED illumination and renewable solar energy saving concepts for indoor lighting.

    Science.gov (United States)

    Tsuei, Chih-Hsuan; Sun, Wen-Shing; Kuo, Chien-Cheng

    2010-11-08

    A hybrid method for using sunlight and light-emitting diode (LED) illumination powered by renewable solar energy for indoor lighting is simulated and presented in this study. We can illuminate an indoor space and collect the solar energy using an optical switching system. When the system is turned off, the full spectrum of the sunlight is concentrated by a concentrator, to be absorbed by solar photovoltaic devices that provide the electricity to power the LEDs. When the system is turned on, the sunlight collected by the concentrator is split into visible and non-visible rays by a beam splitter. The visible rays pass through the light guide into a light box where it is mixed with LED light to ultimately provide uniform illumination by a diffuser. The non-visible rays are absorbed by the solar photovoltaic devices to provide electrical power for the LEDs. Simulation results show that the efficiency of the hybrid sunlight/LED illumination with the renewable solar energy saving design is better than that of LED and traditional lighting systems.

  16. Describing team development within a novel GP-led urgent care centre model : a qualitative study.

    OpenAIRE

    Morton, Sarah; Ignatowicz, Agnieszka; Gnani, Shamini; Majeed, Azeem; Greenfield, Geva

    2016-01-01

    Objective:\\ud Urgent care centres (UCCs) co-located within an emergency department were developed to reduce the numbers of inappropriate emergency department admissions. Since then various UCC models have developed, including a novel general practitioner (GP)-led UCC that incorporates both GPs and emergency nurse practitioners (ENPs). Traditionally these two groups do not work alongside each other within an emergency setting. Although good teamwork is crucial to better patient outcomes, there...

  17. Design of Elliptic Reflective LED Surgical Shadowless Lamps Using Mathematical Optical Tracing Algorithms

    Directory of Open Access Journals (Sweden)

    Cheng-Tang Pan

    2014-01-01

    Full Text Available Traditional surgical shadowless halogen lamps are generally designed as projection type with many light bulbs, which can produce not only mercury pollution but also heat radiation that are serious problems to patient. The study utilized Runge-Kutta methods and mathematical algorithms to design and optimize the freeform lens. The LED (light-emitting diode was adopted to replace the traditional halogen lamp. A uniform lens was designed and fabricated based on the energy conservation. At first, the light field of LED is concentrated through the freeform lens to improve the optical efficiency. Second, the three-shell elliptic curves are applied to the reflective surgical shadowless lamps, where only few LED chips are needed. Light rays emitting from different directions to the target plane can achieve the goal of shadowless. In this study, the LED’s luminance flux is 1,895 lm. The shadow dilution on the target plane is 54%. Ec (central illuminance is 114,900 lux, and the d50/d10 is 57% which is higher than the regulation by 7%, whereas the power consumption is only 20 W. The energy of reflective surgical shadowless lamps can save more than 50%, compared with the traditional projective one.

  18. An accelerated test method of luminous flux depreciation for LED luminaires and lamps

    International Nuclear Information System (INIS)

    Qian, C.; Fan, X.J.; Fan, J.J.; Yuan, C.A.; Zhang, G.Q.

    2016-01-01

    Light Emitting Diode (LED) luminaires and lamps are energy-saving and environmental friendly alternatives to traditional lighting products. However, current luminous flux depreciation test at luminaire and lamp level requires a minimum of 6000 h testing, which is even longer than the product development cycle time. This paper develops an accelerated test method for luminous flux depreciation to reduce the test time within 2000 h at an elevated temperature. The method is based on lumen maintenance boundary curve, obtained from a collection of LED source lumen depreciation data, known as LM-80 data. The exponential decay model and Arrhenius acceleration relationship are used to determine the new threshold of lumen maintenance and acceleration factor. The proposed method has been verified by a number of simulation studies and experimental data for a wide range of LED luminaire and lamp types from both internal and external experiments. The qualification results obtained by the accelerated test method agree well with traditional 6000 h tests. - Highlights: • We develop an accelerated test method for LED luminaires and lamps. • The method is proposed based on a “Boundary Curve” concept. • The parameters of the boundary curve are extracted from LM-80 test reports. • Qualification results from the proposed method agree with ES requirements.

  19. Benefits of pharmacist-led flu vaccination services in community pharmacy.

    Science.gov (United States)

    Kirkdale, C L; Nebout, G; Megerlin, F; Thornley, T

    2017-01-01

    Seasonal influenza is a major cause of excess winter deaths and increased hospital admissions. There is a high level of economic burden associated with the infection. Although vaccination targets have been set to tackle this international issue, many countries struggle to reach these coverage targets for their at-risk populations using traditional delivery methods. Traditional providers include family doctors and nurses; however, pharmacist-led influenza vaccination has become a more commonly utilised aid to support vaccination targets. Community pharmacies are convenient and widely accessible and evaluations consistently demonstrate that patients are satisfied with pharmacist-led vaccinations. Allowing community pharmacists to administer influenza vaccination as an alternative option for delivery helps to increase the coverage rate of vaccination. In addition, commissioning community pharmacists to provide this service has been shown to contribute to achieving targets for those at-risk. Pharmacist-led influenza vaccination services can create value for payors and reduce pressure on health systems. This review aims to demonstrate the success of pharmacy-led influenza vaccinations, and the impact it has had in driving up immunisation rates within other countries. Experiences of countries such as England, Portugal and the United States provide evidence to demonstrate the benefit to both the patient and the health system. Copyright © 2016 Académie Nationale de Pharmacie. Published by Elsevier Masson SAS. All rights reserved.

  20. Is Nigerian Growth Trade-Led?

    Directory of Open Access Journals (Sweden)

    Ismail Adigun Olayemi

    2017-09-01

    Full Text Available Purpose: Nigeria is currently in recession, a situation described as induced by decreases in oil output and export, caused by the bombings of oil pipelines in its Niger Delta region, and the unanticipated decline in its value of exports and currency, resulting from the decline in oil prices. With the export value decline, somersaulting to growth, could it then be that Nigerian economic growth is trade constrained? How important is export to growth?. This study investigates these, its invention balances in its methodology. Design/methodology/approach: To achieve the above, this paper employs the Autoregressive Distributed Lag Model (ARDL and the Thirlwall's Law of balance of payment led growth, using a combination of annual (1981–2016 and quarterly (2000Q1–2016Q4 data to ensure robustness. This combination not only allows for comparison but also ensures the reflection of the current government's trade decisions and trade activities; these are missing in other studies. Findings: Using the Wald F-Statistic, Economic growth is found to be equal to export growth rate divided by income elasticity of import, the estimated income elasticity of import which is greater than 100% or elastic reflects over dependence on import both in the short and long run, implying that Nigeria imports more than it earns. Exchange rate and terms of trade are insignificant especially in the long run. The study calls for monitoring of import contents; the government needs to enforce its recent directives to stop importation of some products that are already being produced within with higher quality and adequate export promotion strategies should be formulated and enforced. Research limitations/implications: The data span is restricted by data availability, the study could as well confirm its results with monthly data for robustness and better confidence, but most of the variables are reported annually and quarterly only. Originality/value: Many studies have confirmed the

  1. Modelling intelligence-led policing to identify its potential

    NARCIS (Netherlands)

    Hengst-Bruggeling, M. den; Graaf, H.A.L.M. de; Scheepstal, P.G.M. van

    2014-01-01

    lntelligence-led policing is a concept of policing that has been applied throughout the world. Despite some encouraging reports, the effect of intelligence-led policing is largely unknown. This paper presents a method with which it is possible to identify intelligence-led policing's potential to

  2. Design methodologies for reliability of SSL LED boards

    NARCIS (Netherlands)

    Jakovenko, J.; Formánek, J.; Perpiñà, X.; Jorda, X.; Vellvehi, M.; Werkhoven, R.J.; Husák, M.; Kunen, J.M.G.; Bancken, P.; Bolt, P.J.; Gasse, A.

    2013-01-01

    This work presents a comparison of various LED board technologies from thermal, mechanical and reliability point of view provided by an accurate 3-D modelling. LED boards are proposed as a possible technology replacement of FR4 LED boards used in 400 lumen retrofit SSL lamps. Presented design

  3. CALiPER Snapshot Report: Indoor LED Luminaires

    Energy Technology Data Exchange (ETDEWEB)

    None

    2014-04-01

    Snapshot reports use data from DOE's LED Lighting Facts product list to compare the LED performance to standard technologies, and are designed to help lighting retailers, distributors, designers, utilities, energy efficiency program sponsors, and other stakeholders understand the current state of the LED market and its trajectory.

  4. Luminaries-level structure improvement of LEDs for heat dissipation ...

    Indian Academy of Sciences (India)

    Heat dissipation enhancement of LED luminaries is of great significance to the large-scale application of LED. Luminaries-level structure improvement by the method of boring through-hole is adopted to intensify heat dissipation. Furthermore, the natural convection heat transfer process of LED luminaries is simulated by ...

  5. EC-LEDS Supports the Low-Carbon Transition

    Energy Technology Data Exchange (ETDEWEB)

    2016-09-01

    EC-LEDS is a flagship U.S. government-led effort that assists countries to create and implement low emission development strategies, or LEDS -- development frameworks that promote sustainable social and economic development while reducing greenhouse gas emissions over the medium to long term.

  6. Thermal design for the high-power LED lamp

    International Nuclear Information System (INIS)

    Tian Xiaogai; Chen Wei; Zhang Jiyong

    2011-01-01

    This paper summarizes different kinds of heat sinks on the market for high power LED lamps. Analysis is made on the thermal model of LED, PCB and heat sink separately with a simplified mode provided. Two examples of simulation are illustrated as a demonstration for the thermal simulation as guidance for LED lamp design. (semiconductor devices)

  7. Mapping Student-Led Peer Learning in the UK

    Science.gov (United States)

    Keenan, Chris

    2014-01-01

    Peer-led academic learning has increased in importance, but there is little sense of how many institutions support it, how they understand its purposes or what peer-led learning best practice is. This report examines the provision of peer-led learning in the UK. It identifies challenges and opportunities, including international perspectives and…

  8. 'No blue' LED solution for photolithography room illumination

    DEFF Research Database (Denmark)

    Ou, Haiyan; Corell, Dennis Dan; Dam-Hansen, Carsten

    2010-01-01

    This paper explored the feasibility of using a LED-based bulb as the illumination light source for photolithography room. A no-blue LED was designed, and the prototype was fabricated. The spectral power distribution of both the LED bulb and the yellow fluorescent tube was measured. Based on that,...

  9. The Hausa Lexicographic Tradition

    Directory of Open Access Journals (Sweden)

    Roxana Ma Newman

    2011-10-01

    Full Text Available

    Abstract: Hausa, a major language of West Africa, is one of the most widely studied languagesof Sub-Saharan Africa. It has a rich lexicographic tradition dating back some two centuries. Sincethe first major vocabulary published in 1843 up to the present time, almost 60 lexicographic works— dictionaries, vocabularies, glossaries — have been published, in a range of metalanguages, fromEnglish to Hausa itself. This article traces the historical development of the major studies accordingto their type and function as general reference works, specialized works, pedagogical works, andterminological works. For each work, there is a general discussion of its size, accuracy of the phonological,lexical, and grammatical information, and the adequacy of its definitions and illustrativematerial. A complete list of the lexicographic works is included.

    Keywords: ARABIC, BILINGUAL LEXICOGRAPHY, DIALECTAL VARIANTS, DICTIONARIES,ENGLISH, ETYMOLOGIES, FRENCH, GERMAN, GLOSSARIES, GRAMMATICALCATEGORIES, HAUSA, LANGUAGE LEARNING, LOANWORDS, NEOLOGISMS, NIGER,NIGERIA, ORTHOGRAPHY, PHONETIC TRANSCRIPTION, PHONOLOGY, RUSSIAN, STANDARDDIALECT, STANDARDIZATION, TERMINOLOGY, VOCABULARIES, WEST AFRICA.

    Opsomming: Die leksikografiese tradisie in Hausa. Hausa, 'n belangrike taal vanWes-Afrika, is een van die tale van Afrika suid van die Sahara wat die wydste bestudeer word. Dithet 'n ryk leksikografiese tradisie wat ongeveer twee eeue oud is. Van die eerste groot woordeboekwat in 1843 gepubliseer is tot die hede is ongeveer 60 leksikografiese werke — woordeboeke,naamlyste, woordelyste — gepubliseer in 'n reeks metatale van Engels tot Hausa self. Hierdie artikelgaan die historiese ontwikkeling van die groter studies aan die hand van hulle tipe en funksieas algemene naslaanwerke, gespesialiseerde werke, opvoedkundige werke, en terminologiesewerke na. Vir elke werk is daar 'n algemene bespreking oor sy grootte, akkuraatheid van die fonologiese,leksikale en

  10. Improving patient access to videofluoroscopy services: Role of the practitioner-led clinic

    Energy Technology Data Exchange (ETDEWEB)

    Newman, Roger D., E-mail: Roger.Newman@lthtr.nhs.uk [Dept. of Speech and Language Therapy, Lancashire Teaching Hospitals, Sharoe Green lane, Fulwood, Preston PR2 9HT (United Kingdom); University of Salford (United Kingdom); Nightingale, Julie [University of Salford (United Kingdom)

    2011-11-15

    Quality Issue: Although costly and time consuming, videofluoroscopic swallowing (VFS) examinations are the gold standard for imaging of oro-pharyngeal dysphagia, and demand is likely to increase with an ageing population. Traditional radiologist-led VFS services in the UK are gradually being replaced by practitioner-led clinics undertaken jointly by speech and language therapists and radiographers. This article explores the impact on patient access of a practitioner-led VFS clinic at a large teaching hospital. Initial Assessment: Specific information pertaining to VFS patient waiting times and service quality was collected for a twelve month period both pre- and post-clinic formation. Choice of Solution: Additional capacity was achieved with the introduction of the practitioner-led clinic, with overall patient access improving by 111%. Mean waiting times for in-patients reduced by 75%, many of whom had the procedure on the same day as referral, with out-patients waiting times reducing by 62.5%. Evaluation: The data demonstrates that patient access and report turnaround times are significantly improved, with no adverse effects as measured by inadequate studies, incorrect reports, complaints and documented radiation dose levels. Lessons Learnt: Practitioner-led VFS services can be recommended as a safe and efficient method of improving service provision.

  11. Improving patient access to videofluoroscopy services: Role of the practitioner-led clinic

    International Nuclear Information System (INIS)

    Newman, Roger D.; Nightingale, Julie

    2011-01-01

    Quality Issue: Although costly and time consuming, videofluoroscopic swallowing (VFS) examinations are the gold standard for imaging of oro-pharyngeal dysphagia, and demand is likely to increase with an ageing population. Traditional radiologist-led VFS services in the UK are gradually being replaced by practitioner-led clinics undertaken jointly by speech and language therapists and radiographers. This article explores the impact on patient access of a practitioner-led VFS clinic at a large teaching hospital. Initial Assessment: Specific information pertaining to VFS patient waiting times and service quality was collected for a twelve month period both pre- and post-clinic formation. Choice of Solution: Additional capacity was achieved with the introduction of the practitioner-led clinic, with overall patient access improving by 111%. Mean waiting times for in-patients reduced by 75%, many of whom had the procedure on the same day as referral, with out-patients waiting times reducing by 62.5%. Evaluation: The data demonstrates that patient access and report turnaround times are significantly improved, with no adverse effects as measured by inadequate studies, incorrect reports, complaints and documented radiation dose levels. Lessons Learnt: Practitioner-led VFS services can be recommended as a safe and efficient method of improving service provision.

  12. Medical students' learning from patient-led teaching: experiential versus biomedical knowledge.

    Science.gov (United States)

    Henriksen, Ann-Helen; Ringsted, Charlotte

    2014-03-01

    The aim of this study was to explore how medical students perceive the experience of learning from patient instructors (patients with rheumatism who teach health professionals and students) in the context of coupled faculty-led and patient-led teaching session. This was an explorative study with a qualitative approach based on focus group interviews. Analysis was based on a prior developed model of the characteristics of learning from patient instructors. The authors used this model as sensitizing concepts for the analysis of data while at the same time being open to new insights by constant comparison of old and new findings. Results showed a negotiation both between and within the students of the importance of patients' experiential knowledge versus scientific biomedical knowledge. On one hand students appreciated the experiential learning environment offered in the PI-led sessions representing a patient-centred approach, and acknowledged the importance of the PIs' individual perspectives and experiential knowledge. On the other hand, representing the scientific biomedical perspective and traditional step-by step teaching, students expressed unfamiliarity with the unstructured experiential learning and scepticism regarding the credibility of the patients' knowledge. This study contributes to the understanding of the complexity of involving patients as teachers in healthcare education and initiates a discussion on how to complement faculty-led teaching with patient-led teaching involving varying degrees of patient autonomy in the planning and delivering of the teaching.

  13. Non-destructive inspection methods for LEDs using real-time displaying Optical Coherence Tomography.

    Science.gov (United States)

    Cho, Nam Hyun; Jung, Unsang; Kim, Suhwan; Kim, Jeehyun

    2012-01-01

    In this study, we report the applicability of two different Optical Coherence Tomography (OCT) technologies for inspecting Light Emitting Diode (LED) structures. Sectional images of a LED were captured using a Spectral Domain OCT (SD-OCT) system and a Swept Source OCT (SS-OCT) system. Their center wavelengths are 850 and 1,310 nm, respectively. We acquired cross-sectional two dimensional (2D) images of a normal LED and extracted sectional profiles to inspect possible wire disconnection that may be present in the LED manufacturing process. The SD-OCT and SS-OCT images were compared with each other in the same sample to study their advantages. The distribution of fluorescence material was observed more clearly with the SD-OCT of 850 nm wavelength, whereas the status of wire connection was clearer in the SS-OCT images with 1,310 nm wavelength. In addition, the volume of the fluorophore space was calculated from the OCT images. This is the first report that a nondestructive optical imaging modality such as OCT can be applied to finding screen defects in LED. We expect this method can improve the inspection efficacy over traditional inspection methods such as Charged Coupled Device (CCD) camera or X-ray instruments.

  14. Non-Destructive Inspection Methods for LEDs Using Real-Time Displaying Optical Coherence Tomography

    Directory of Open Access Journals (Sweden)

    Suhwan Kim

    2012-07-01

    Full Text Available In this study, we report the applicability of two different Optical Coherence Tomography (OCT technologies for inspecting Light Emitting Diode (LED structures. Sectional images of a LED were captured using a Spectral Domain OCT (SD-OCT system and a Swept Source OCT (SS-OCT system. Their center wavelengths are 850 and 1,310 nm, respectively. We acquired cross-sectional two dimensional (2D images of a normal LED and extracted sectional profiles to inspect possible wire disconnection that may be present in the LED manufacturing process. The SD-OCT and SS-OCT images were compared with each other in the same sample to study their advantages. The distribution of fluorescence material was observed more clearly with the SD-OCT of 850 nm wavelength, whereas the status of wire connection was clearer in the SS-OCT images with 1,310 nm wavelength. In addition, the volume of the fluorophore space was calculated from the OCT images. This is the first report that a nondestructive optical imaging modality such as OCT can be applied to finding screen defects in LED. We expect this method can improve the inspection efficacy over traditional inspection methods such as Charged Coupled Device (CCD camera or X-ray instruments.

  15. Three-chip LED illumination system for laparoscopy and minimal access surgery applications

    Science.gov (United States)

    Ye, Bin; Wang, Liqiang; Duan, Huilong

    2010-11-01

    Light-emitting diodes (LEDs) bring great flexibility in color choice and high luminous efficacy design for biomedical illumination. Based on the state-of-the-art LED chips, a three-chip LED illumination system was developed specially for laparoscopy and minimal access surgery. White light is produced by mixing three specific wavelengths of amber red, true green and blue, and then coupled into a fiber-optic light guide with 2mm diameter. The whole device has a compact size of 145mm × 92mm × 84 mm which is more suitable than a conventional xenon lamp source for portable endoscopes. The illuminance and color characteristic of the three-chip model were analyzed, compared to those of traditional light source. A maximum illuminance of 1960 lux was obtained at the distance of 100 mm, with the average current of 450 mA of the LEDs. Additionally, a simulation environment had been set up to find out the performance of the endo-illuminator in the specific circumstance, which was closer distance and crawl space. Experiments showed that images taken under the three-chip LED illumination had better contrast and saturation. With the temperature of 31.5 degrees Celsius at the end of the fiber bundle, the endo-illuminator is also a cold light source.

  16. LED surgical lighting system with multiple free-form surfaces for highly sterile operating theater application.

    Science.gov (United States)

    Liu, Peng; Zhang, Yaqin; Zheng, Zhenrong; Li, Haifeng; Liu, Xu

    2014-06-01

    Although the ventilation system is widely employed in the operating theater, a strictly sterile surgical environment still cannot be ensured because of laminar disturbance, which is mainly caused by the surgical lighting system. Abandoning traditional products, we propose an LED surgical lighting system, which can alleviate the laminar disturbance and provide an appropriate lighting condition for surgery. It contains a certain amount of LED lens units, which are embedded in the ceiling and arranged around the air supply smallpox. The LED lens unit integrated with an LED light source and a free-form lens is required to produce a uniform circular illumination with a large tolerance to the change of lighting distance. To achieve such a dedicated lens, two free-form refractive surfaces, which are converted into two ordinary differential equations by the design method presented in this paper, are used to deflect the rays. The results show that the LED surgical lighting system can provide an excellent illumination environment for surgery, and, apparently, the laminar disturbance also can be relieved.

  17. Complementary therapies and traditional Judaism.

    Science.gov (United States)

    Rosner, F

    1999-03-01

    In Jewish tradition, physicians are obligated to heal the sick and patients are obligated to seek healing from physicians. Judaism also sanctions certain complementary therapies such as prayers, faith healing, and amulets, when used as supplements to traditional medical therapy. Confidence in the healing powers of God through prayer and contrition is encouraged, provided that the patient uses prayer alongside traditional scientific medicine, not as a substitute for it.

  18. Reception of the Istrian musical tradition(s

    Directory of Open Access Journals (Sweden)

    Marušić Dario

    2007-01-01

    Full Text Available The successive colonization of Istria with culturally differentiated populations, and peripheral position of the peninsula regarding both the Latin and Slav worlds, has conditioned interesting phenomena which defines the traditional life of the province. On the spiritual level it is primarily reflected in two cultural dimensions: the language and traditional music.

  19. Attitudes of radiographers to radiographer-led discharge: A survey

    International Nuclear Information System (INIS)

    Lumsden, Laura; Cosson, Philip

    2015-01-01

    Background: The traditional role of the Diagnostic Radiographer in image acquisition has gradually been extended through skill-mix, particularly to include abnormality detection. Aims: This research focused on the attitudes of Radiographers to Radiographer-led Discharge (RLD), where Radiographers discharge patients with minor injuries and perform tasks previously undertaken by Accident and Emergency staff. The effects of job role, hospital type, experience and whether RLD was used in the participant's trust were examined. Method: A multiple-indicator online questionnaire assessed attitudes to RLD. Snowball sampling was used with advertisement via emails, posters and cards, containing Quick Response (QR) codes. Statement responses were coded, with reverse coding for negative statements and total scores were calculated. A higher score represented a more positive attitude. Results: 101 questionnaires were completed (an estimated 30% response rate) and the mean total score was 84/115. 95% of participants supported radiographer involvement in abnormality detection, with 46.5% selecting RLD as the preferred system for minor injuries patients vs 48.5% preferring commenting alone. Discussion: Participants were positive about extending their role through RLD and felt confident in their image interpretation abilities, though expressed concern for the legal consequences of the role and adequate pay. Generalization of the results is limited due to the possible low response rate. Conclusion: Overall, participants demonstrated positive attitudes towards RLD but they also indicate the need for appropriate payment for any additional responsibility. These findings are promising for successful implementation of RLD, though larger-scale research including radiologists, business managers, A and E staff and patients would be beneficial. - Highlights: • 101 questionnaires were completed (an estimated 30% response rate). • 95% of participants supported radiographer involvement

  20. Novel Carbazole Skeleton-Based Photoinitiators for LED Polymerization and LED Projector 3D Printing

    Directory of Open Access Journals (Sweden)

    Assi Al Mousawi

    2017-12-01

    Full Text Available Radical chemistry is a very convenient way to produce polymer materials. Here, an application of a particular photoinduced radical chemistry is illustrated. Seven new carbazole derivatives Cd1–Cd7 are incorporated and proposed as high performance near-UV photoinitiators for both the free radical polymerization (FRP of (methacrylates and the cationic polymerization (CP of epoxides utilizing Light Emitting Diodes LEDs @405 nm. Excellent polymerization-initiating abilities are found and high final reactive function conversions are obtained. Interestingly, these new derivatives display much better near-UV polymerization-initiating abilities compared to a reference UV absorbing carbazole (CARET 9H-carbazole-9-ethanol demonstrating that the new substituents have good ability to red shift the absorption of the proposed photoinitiators. All the more strikingly, in combination with iodonium salt, Cd1–Cd7 are likewise preferred as cationic photoinitiators over the notable photoinitiator bis(2,4,6-trimethylbenzoylphenylphosphine oxide (BAPO for mild irradiation conditions featuring their remarkable reactivity. In particular their utilization in the preparation of new cationic resins for LED projector 3D printing is envisioned. A full picture of the included photochemical mechanisms is given.

  1. Financial products as alternatives to traditional deposits

    Directory of Open Access Journals (Sweden)

    Cristina Lidia MANEA

    2016-05-01

    In this context, increasing the safety of depositors appears as an undisputed necessity, which translates to our approach in the development of a constructive type applied research that takes into account the following stages: short description of risks and uncertainties characterizing the economic environment with emphasis on the importance of the financial instruments; analysis of empirical data on deposits in lei and euro at national level, identifying possible causes which led to one preference or another and finding the causes underlying the different options manifested in the capital, as compared to other counties; identifying the products that offer a dangerous alternative to traditional deposits from the Romanian banking market and describing these products and their related risks; the proposal of a new product, demonstrating its effectiveness by testing and confirmation of two hypotheses.

  2. The Canarian Camel: A Traditional Dromedary Population

    Directory of Open Access Journals (Sweden)

    Ursula Schulz

    2010-04-01

    Full Text Available The domestic camel (dromedary is the most important livestock species in the Canary Islands and the most important autochthonous European camel population. After six centuries of a successful adaptation process to the particular environment of the Canary Islands, the abandonment of traditional agriculture has led this population to a major bottleneck. Along with a lack of foreign genetic interchanges, this could lead the population to the brink of extinction. Genetic analysis using 13 microsatellites showed the closest genetic proximity to the North African (Tindouf, Algeria camel population and a certain degree of sub-division, with significant genetic differences among breeders. An important level of genetic differentiation among the different populations analyzed was found with a global FST value of 0.116.

  3. A First Nations-led social innovation: a moose, a gold mining company, and a policy window

    Directory of Open Access Journals (Sweden)

    Daniel D. P. McCarthy

    2014-12-01

    combined with several other factors, including: (1 the high price of gold; (2 a mining company seeking to demonstrate corporate social responsibility to repair its international reputation with indigenous peoples by supporting an innovative, local Indigenous-led initiative; and (3 a new policy context, including Supreme Court of Canada decisions and provisions in the updated Ontario Mining Act, that require meaningful consultation with indigenous peoples has led to the emergence of a indigenous peoples-led collaborative, social innovation. This policy window allowed for the formation of an unprecedented council of indigenous knowledge holders (elders and traditional practitioners to help inform mine restoration and practice as well as to foster the resurgence of traditional language and culture in local indigenous communities. Here, we document this unprecedented social change opportunity.

  4. Can the computer replace the adult for storybook reading? A meta-analysis on the effects of multimedia stories as compared to sharing print stories with an adult

    Science.gov (United States)

    Takacs, Zsofia K.; Swart, Elise K.; Bus, Adriana G.

    2014-01-01

    The present meta-analysis challenges the notion that young children necessarily need adult scaffolding in order to understand a narrative story and learn words as long as they encounter optimally designed multimedia stories. Including 29 studies and 1272 children, multimedia stories were found more beneficial than encounters with traditional story materials that did not include the help of an adult for story comprehension (g+ = 0.40, k = 18) as well as vocabulary (g+ = 0.30, k = 11). However, no significant differences were found between the learning outcomes of multimedia stories and sharing traditional print-like stories with an adult. It is concluded that multimedia features like animated illustrations, background music and sound effects provide similar scaffolding of story comprehension and word learning as an adult. PMID:25520684

  5. Can the computer replace the adult for storybook reading? A meta-analysis on the effects of multimedia stories as compared to sharing print stories with an adult.

    Directory of Open Access Journals (Sweden)

    Zsofia Katalin Takacs

    2014-12-01

    Full Text Available The present meta-analysis challenges the notion that young children necessarily need adult scaffolding in order to understand a narrative story and learn words as long as they encounter optimally designed multimedia stories. Including 29 studies and 1272 children, multimedia stories were found more beneficial than encounters with traditional story materials that did not include the help of an adult for story comprehension (g+ = 0.40, k = 18 as well as vocabulary (g+ = 0.30, k = 11. However, no significant differences were found between the learning outcomes of multimedia stories and sharing traditional print-like stories with an adult. It is concluded that multimedia features like animated illustrations, background music and sound effects provide similar scaffolding of story comprehension and word learning as an adult.

  6. Can the computer replace the adult for storybook reading? A meta-analysis on the effects of multimedia stories as compared to sharing print stories with an adult.

    Science.gov (United States)

    Takacs, Zsofia K; Swart, Elise K; Bus, Adriana G

    2014-01-01

    The present meta-analysis challenges the notion that young children necessarily need adult scaffolding in order to understand a narrative story and learn words as long as they encounter optimally designed multimedia stories. Including 29 studies and 1272 children, multimedia stories were found more beneficial than encounters with traditional story materials that did not include the help of an adult for story comprehension (g+ = 0.40, k = 18) as well as vocabulary (g+ = 0.30, k = 11). However, no significant differences were found between the learning outcomes of multimedia stories and sharing traditional print-like stories with an adult. It is concluded that multimedia features like animated illustrations, background music and sound effects provide similar scaffolding of story comprehension and word learning as an adult.

  7. Biodiversity, carbon stocks and community monitoring in traditional agroforestry practices

    DEFF Research Database (Denmark)

    Hartoyo, Adisti Permatasari Putri; Siregar, Iskandar Z.; Supriyanto

    2016-01-01

    Traditional agroforestry practices in Berau, East Kalimantan, are suitable land use types to conserve that potentially support the implementation of REDD+. The objectives of this research are to assess biodiversity and carbon stock in various traditional agroforestry practices, also to determine...... the accuracy of the ability levels of local community in biodiversity and carbon stock monitoring. This paper presents the implementation plan and preliminary data in Kampung Birang and Kampung Merabu, in Berau district. Professional forester-led methods of biodiversity and carbon stock assessment follow...

  8. An mHealth monitoring system for traditional birth attendant-led antenatal risk assessment in rural Guatemala.

    Science.gov (United States)

    Stroux, Lisa; Martinez, Boris; Coyote Ixen, Enma; King, Nora; Hall-Clifford, Rachel; Rohloff, Peter; Clifford, Gari D

    Limited funding for medical technology, low levels of education and poor infrastructure for delivering and maintaining technology severely limit medical decision support in low- and middle-income countries. Perinatal and maternal mortality is of particular concern with millions dying every year from potentially treatable conditions. Guatemala has one of the worst maternal mortality ratios, the highest incidence of intra-uterine growth restriction (IUGR), and one of the lowest gross national incomes per capita within Latin America. To address the lack of decision support in rural Guatemala, a smartphone-based system is proposed including peripheral sensors, such as a handheld Doppler for the identification of foetal compromise. Designed for use by illiterate birth attendants, the system uses pictograms, audio guidance, local and cloud processing, SMS alerts and voice calling. The initial prototype was evaluated on 22 women in highland Guatemala. Results were fed back into the refinement of the system, currently undergoing RCT evaluation.

  9. Comparison between peer-led and teacher-led education in tuberculosis prevention in rural middle schools in Chongqing, China.

    Science.gov (United States)

    Liu, Qin; Liu, Liping; Vu, Huyen; Liu, Xiaoxue; Tang, Shenglan; Wang, Hong

    2015-03-01

    The aim of this study was to investigate the efficacy of tuberculosis (TB) education through a comparison of peer-led and teacher-led methods of education about TB prevention among middle school students in rural Chongqing, China. A preintervention and postintervention questionnaire survey was conducted in 2 different middle school student groups to measure changes in knowledge, attitude, and practice (KAP) status of those students before and after each TB education program. Of 1265 students participating in the preintervention survey, 1176 completed the postintervention survey. KAP scores of both peer-led and teacher-led groups after intervention improved by as much as 2 times compared with before the intervention and those of the control group (P led education group (P led group had a larger improvement than the peer-led group in practice scores (P < .01) in immediate effect evaluation. © 2013 APJPH.

  10. Development of high-performance solar LED lighting system

    KAUST Repository

    Huang, B.J.

    2010-08-01

    The present study developed a high-performance charge/discharge controller for stand-alone solar LED lighting system by incorporating an nMPPO system design, a PWM battery charge control, and a PWM battery discharge control to directly drive the LED. The MPPT controller can then be removed from the stand-alone solar system and the charged capacity of the battery increases 9.7%. For LED driven by PWM current directly from battery, a reliability test for the light decay of LED lamps was performed continuously for 13,200 h. It has shown that the light decay of PWM-driven LED is the same as that of constant-current driven LED. The switching energy loss of the MOSFET in the PWM battery discharge control is less than 1%. Three solar-powered LED lighting systems (18 W, 100 W and 150 W LED) were designed and built. The long-term outdoor field test results have shown that the system performance is satisfactory with the control system developed in the present study. The loss of load probability for the 18 W solar LED system is 14.1% in winter and zero in summer. For the 100 W solar LED system, the loss of load probability is 3.6% in spring. © 2009 Elsevier Ltd. All rights reserved.

  11. How 'Digital' is Traditional Crime?

    NARCIS (Netherlands)

    Montoya, L.; Junger, Marianne; Hartel, Pieter H.

    Measuring how much cybercrime exists is typically done by first defining cybercrime and then quantifying how many cases fit that definition. The drawback is that definitions vary across countries and many cybercrimes are recorded as traditional crimes. An alternative is to keep traditional

  12. Development of gallium-nitride-based light-emitting diodes (LEDs) and laser diodes for energy-efficient lighting and displays

    International Nuclear Information System (INIS)

    DenBaars, Steven P.; Feezell, Daniel; Kelchner, Katheryn; Pimputkar, Siddha; Pan, Chi-Chen; Yen, Chia-Chen; Tanaka, Shinichi; Zhao, Yuji; Pfaff, Nathan; Farrell, Robert; Iza, Mike; Keller, Stacia; Mishra, Umesh; Speck, James S.; Nakamura, Shuji

    2013-01-01

    Light-emitting diodes (LEDs) fabricated from gallium nitride (GaN) have led to the realization of high-efficiency white solid-state lighting. Currently, GaN white LEDs exhibit luminous efficacy greater than 150 lm W −1 , and external quantum efficiencies higher than 60%. This has enabled LEDs to compete with traditional lighting technologies, such as incandescent and compact fluorescent (CFL) lighting. Further improvements in materials quality and cost reduction are necessary for widespread adoption of LEDs for lighting. A review of the unique polarization anisotropy in GaN is included for the different crystal orientations. The emphasis on nonpolar and semipolar LEDs highlights high-power violet and blue emitters, and we consider the effects of indium incorporation and well width. Semipolar GaN materials have enabled the development of high-efficiency LEDs in the blue region and recent achievements of green laser diodes at 520 nm

  13. LED light engine concept with ultra-high scalable luminance

    Science.gov (United States)

    Hoelen, Christoph; de Boer, Dick; Bruls, Dominique; van der Eyden, Joost; Koole, Rolf; Li, Yun; Mirsadeghi, Mo; Vanbroekhoven, Vincent; Van den Bergh, John-John; Van de Voorde, Patrick

    2016-03-01

    Although LEDs have been introduced successfully in many general lighting applications during the past decade, high brightness light source applications are still suffering from the limited luminance of LEDs. High power LEDs are generally limited in luminance to ca 100 Mnit (108 lm/m2sr) or less, while dedicated devices for projection may achieve luminance values up to ca 300 Mnit with phosphor converted green. In particular for high luminous flux applications with limited étendue, like in front projection systems, only very modest luminous flux values in the beam can be achieved with LEDs compared to systems based on discharge lamps. In this paper we introduce a light engine concept based on a light converter rod pumped with blue LEDs that breaks through the étendue and brightness limits of LEDs, enabling LED light source luminance values that are more than 4 times higher than what can be achieved with LEDs so far. In LED front projection systems, green LEDs are the main limiting factor. With our green light emitting modules, peak luminance values well above 1.2 Gnit have been achieved, enabling doubling of the screen brightness of LED based DLP projection systems, and even more when this technology is applied to other colors as well. This light source concept, introduced as the ColorSpark High Lumen Density (HLD) LED technology, enables a breakthrough in the performance of LED-based light engines not only for projection, where >2700 ANSI lm was demonstrated, but for a wide variety of high brightness applications.

  14. Understanding Traditional Research Impact Metrics.

    Science.gov (United States)

    Butler, Joseph S; Sebastian, Arjun S; Kaye, I David; Wagner, Scott C; Morrissey, Patrick B; Schroeder, Gregory D; Kepler, Christopher K; Vaccaro, Alexander R

    2017-05-01

    Traditionally, the success of a researcher has been judged by the number of publications he or she has published in peer-review, indexed, high impact journals. However, to quantify the impact of research in the wider scientific community, a number of traditional metrics have been used, including Impact Factor, SCImago Journal Rank, Eigenfactor Score, and Article Influence Score. This article attempts to provide a broad overview of the main traditional impact metrics that have been used to assess scholarly output and research impact. We determine that there is no perfect all-encompassing metric to measure research impact, and, in the modern era, no single traditional metric is capable of accommodating all facets of research impact. Academics and researchers should be aware of the advantages and limitations of traditional metrics and should be judicious when selecting any metrics for an objective assessment of scholarly output and research impact.

  15. Intelligent control of dynamic LED lighting; Intelligent styring af dynamisk LED belysning. Slutrapport

    Energy Technology Data Exchange (ETDEWEB)

    Thorseth, A.; Corell, D.; Hansen, Soeren S.; Dam-Hansen, C.; Petersen, Paul Michael

    2013-01-15

    The project has resulted in a prototype of a new intelligent lighting control system. The control system enables the end user to control his or her own local lighting environment (lighting zone) according to individual preferences and needs. The report provides a description of how the developed intelligent lighting system is composed and functions. The system is designed as a work lamp that enables dynamic change of the light color scheme according to a number of light control algorithms. It is specifically designed in relation to user tests of the intelligent lighting system, which is carried out in the final part of the project. An intelligent and advanced control of LED lighting was developed, which enables optimization of the user's light conditions in a given situation. Based on a number of known parameters, the system can control lighting so that at any time optimal light conditions are created, using a minimum of electric power. (LN)

  16. The commercialization of traditional medicine in modern Cambodia.

    Science.gov (United States)

    Ros, Bandeth; Lê, Gillian; McPake, Barbara; Fustukian, Suzanne

    2018-01-01

    Globally, traditional medicine has long been used to address relatively common illness, mental ill health and during childbirth and post-natal care. However, traditional medicine is primarily provided by the private sector and it is unclear how far expenditures on traditional medicine contribute to household impoverishment. A life history method was used to understand the health seeking experience of 24 households over the last 60 years in Cambodia, a country with high out-of-pocket expenditures for health. The life histories suggest that traditional medicine in Cambodia has been undergoing a process of commercialization, with significant impacts on poor households. In the earlier lives of respondents, payments for traditional medicine were reported to have been flexible, voluntary or appropriate to patients' financial means. In contrast, contemporary practitioners appear to seek immediate cash payments that have frequently led to considerable debt and asset sales by traditional medicine users. Given traditional medicine's popularity as a source of treatment in Cambodia and its potential to contribute to household impoverishment, we suggest that it needs to be included in a national conversation about achieving Universal Health Coverage in the country. © The Author 2017. Published by Oxford University Press in association with The London School of Hygiene and Tropical Medicine.

  17. Characteristics of white LED transmission through a smoke screen

    Science.gov (United States)

    Zheng, Yunfei; Yang, Aiying; Feng, Lihui; Guo, Peng

    2018-01-01

    The characteristics of white LED transmission through a smoke screen is critical for visible light communication through a smoke screen. Based on the Mie scattering theory, the Monte Carlo transmission model is established. Based on the probability density function, the white LED sampling model is established according to the measured spectrum of a white LED and the distribution angle of the lambert model. The sampling model of smoke screen particle diameter is also established according to its distribution. We simulate numerically the influence the smoke thickness, the smoke concentration and the angle of irradiance of white LED on transmittance of the white LED. We construct a white LED smoke transmission experiment system. The measured result on the light transmittance and the smoke concentration agreed with the simulated result, and demonstrated the validity of simulation model for visible light transmission channel through a smoke screen.

  18. Competing in the Global LED Industry: The Case of Taiwan

    Directory of Open Access Journals (Sweden)

    Yu-Shan Su

    2014-01-01

    Full Text Available Light-emitting diode (LED is a very essential application for energy-savings nowadays. The revenue of the Taiwan LED components industry is ranked top one in the world, followed by that of Japan and South Korea. Based on the advantage of their electronics industry, Taiwanese LED companies create a unique model to compete with the international firms. Large international LED companies achieve economies of scale by vertically integrating their operations. Taiwanese LED companies specialize and achieve an optimal efficiency by vertically disintegrating across the upstream, midstream, and downstream sectors in the value chains. Taiwanese LED companies create economies of scale and economies of scope through a complete industrial value chain.

  19. A novel amblyopia treatment system based on LED light source

    Science.gov (United States)

    Zhang, Xiaoqing; Chen, Qingshan; Wang, Xiaoling

    2011-05-01

    A novel LED (light emitting diode) light source of five different colors (white, red, green, blue and yellow) is adopted instead of conventional incandescent lamps for an amblyopia treatment system and seven training methods for rectifying amblyopia are incorporated so as for achieving an integrated therapy. The LED light source is designed to provide uniform illumination, adjustable light intensity and alterable colors. Experimental tests indicate that the LED light source operates steadily and fulfills the technical demand of amblyopia treatment.

  20. Development of Wireless Dimming Control System for LED Stage Light

    OpenAIRE

    Wang Hui Qin; Bai Shi Lei

    2016-01-01

    Compared with the existing wire dimming system of LED stage light which uses the heavy light operating console to adjust the brightness of stage light, a portable wireless dimming control system for LED stage lighting is proposed, fabricated and tested in this paper. The scheme with the core of ATmega16L microcontroller is composed of wireless transmission and reception units, constant current driving circuit of LED, and the control circuit between this two modules. Through the system present...

  1. Null bactericidal effect of ultraviolet radiation emitted by LEDs.

    OpenAIRE

    Francisco Alcántara Muñoz; Rafael Moreno-Rojas; Alicia Moreno Ortega; José Emilio Muñoz Cañete; Rafael Gómez Díaz

    2016-01-01

    This research has aimed to assess the bactericidal effect of ultraviolet light emitted by LEDS on the growth on Petri dishes of microorganisms whose legal limits in foods have been established. An electrically fed apparatus has been designed with precise timing and a camera to prevent light spillage, in which two ultraviolet radiation emission devices were connected by LED technology at different wavelengths: through an array of LEDS emitting at around 350nm, and a single specific...

  2. Interior LED Lighting Technology. Navy Energy Technology Validation (Techval) Program

    Science.gov (United States)

    2015-09-01

    evaluated using the Illumination Engineering Societies’ (IES) TM-21 manual. The TM- 21 manual provides a standardized method for evaluating when an LED...the equipment. The Cree luminaires installed in this study are rated for 75,000 hours of service, based on calculation methods that extrapolated...should be replaced with LED lamps. • Replace MR-16 lamps with LED lamps since this type of fixture is used to provide accent lighting and is

  3. Warm white LEDs lighting over Ra=95 and its applications

    Science.gov (United States)

    Kobashi, Katsuya; Taguchi, Tsunemasa

    2007-02-01

    We have for the first time developed warm white LEDs lighting using a combination of near ultraviolet LED and three-band (red, green and blue) white phosphors. This LED has the average color-rendering index Ra=96. Moreover, special color-rendering index R9 (red) and R15 (face color of Japanese) are estimated to be 95 and 97, respectively. We will describe the results of evaluation on the medical lighting applications such as operation, treatment and endoscope experiments, application to the LED fashions and application to the Japanese antique art (ink painting) lighting.

  4. A synthetic method of solar spectrum based on LED

    Science.gov (United States)

    Wang, Ji-qiang; Su, Shi; Zhang, Guo-yu; Zhang, Jian

    2017-10-01

    A synthetic method of solar spectrum which based on the spectral characteristics of the solar spectrum and LED, and the principle of arbitrary spectral synthesis was studied by using 14 kinds of LED with different central wavelengths.The LED and solar spectrum data were selected by Origin Software firstly, then calculated the total number of LED for each center band by the transformation relation between brightness and illumination and Least Squares Curve Fit in Matlab.Finally, the spectrum curve of AM1.5 standard solar spectrum was obtained. The results met the technical indexes of the solar spectrum matching with ±20% and the solar constant with >0.5.

  5. Excellent color rendering indexes of multi-package white LEDs.

    Science.gov (United States)

    Oh, Ji Hye; Yang, Su Ji; Sung, Yeon-Goog; Do, Y R

    2012-08-27

    This study introduces multi-package white light-emitting diodes (LEDs) system with the ability to realize high luminous efficacy and an excellent color rendering index (CRI, R a) using the R B,M A B,M G B,M C B (R B,M A B,M G B,M denoted as a long-pass dichroic filter (LPDF)-capped, monochromatic red, amber and green phosphor converted-LED (pc-LED) pumped by a blue LED chip, and C B denoted as a cyan and blue mixed pc-LED pumped by a blue LED) system. The luminous efficacy and color rendering index (CRI) of multi-package white LED systems are compared while changing the concentration of the cyan phosphor used in the paste of a cyan-blue LED package and the driving current of individual LEDs in multi-package white LEDs at correlated color temperatures (CCTs) ranging from 6,500 K (cold white) to 2,700 K (warm white) using a set of eight CCTs as specified by the American National Standards Institute (ANSI) standard number C78.377-2008. A R B,M A B,M G B,M C B white LED system provides high luminous efficacy (≥ 96 lm/W) and a color rendering index (≥ 91) encompassing the complete CCT range. We also compare the optical properties of the R B,M A B,M G B,M C B system with those of the R B,M A B,M G B,M B and RAGB (red, amber, green, and blue semiconductor-type narrow-spectrum-band LEDs) systems. It can be expected that the cyan color added to a blue LED in multi-package white LEDs based on LPDF-capped, phosphor-converted monochromatic LEDs will meet the needs of the high-quality, highly efficient, full-color white LED lighting market in the near future.

  6. UV-LED Curing Efficiency of Wood Coatings

    OpenAIRE

    Landry, Véronic; Blanchet, Pierre; Boivin, Gabrielle; Bouffard, Jean-François; Vlad, Mirela

    2015-01-01

    Ultraviolet light emitting diodes (UV-LEDs) have attracted great interest in recent years. They can be used to polymerize coatings, such as those used for prefinished wood flooring. In this project, two lamps were compared for their suitability to be used on a wood flooring finishing line: a UV-microwave and a UV-LED lamp. Low heat emission was found for the UV-LED lamp compared to the UV-microwave one. This study also reveals that the 4 W/cm2 UV-LED lamp used is not powerful enough to cure ...

  7. High-Modulation-Speed LEDs Based on III-Nitride

    Science.gov (United States)

    Chen, Hong

    III-nitride InGaN light-emitting diodes (LEDs) enable wide range of applications in solid-state lighting, full-color displays, and high-speed visible-light communication. Conventional InGaN quantum well LEDs grown on polar c-plane substrate suffer from quantum confined Stark effect due to the large internal polarization-related fields, leading to a reduced radiative recombination rate and device efficiency, which limits the performance of InGaN LEDs in high-speed communication applications. To circumvent these negative effects, non-trivial-cavity designs such as flip-chip LEDs, metallic grating coated LEDs are proposed. This oral defense will show the works on the high-modulation-speed LEDs from basic ideas to applications. Fundamental principles such as rate equations for LEDs/laser diodes (LDs), plasmonic effects, Purcell effects will be briefly introduced. For applications, the modal properties of flip-chip LEDs are solved by implementing finite difference method in order to study the modulation response. The emission properties of highly polarized InGaN LEDs coated by metallic gratings are also investigated by finite difference time domain method.

  8. LED package with Dome/side-emitting-enhancement silicone lens achieved by dispensing and geometry transferring

    Science.gov (United States)

    Chang Chien, Chien-Lin; Huang, Yu-Che; Hu, Syue-Fong; Sun, Chang-Wen; Chang, Chung-Min; Hsu, Chih-Peng; Yip, Ming-Chuen; Fang, Weileun

    2012-10-01

    This study presents a structure design and process method for lens type LED package. Dome type or side-emitting-enhancement silicone lens without molding process are achieved. The ceramic ring is adopted as the confine for the encapsulant. The surface intension along the sidewall of ceramic ring and silicone surface, the cohesion force and the gravity of silicone determine the shape of dome type silicone lens. The cone shape tooling coated with a releasing material is immersed into the dome type silicone lens before the silicone fully hardening. After curing simultaneously, to remove the tooling from package, the package with side-emitting-enhancement silicone lens is finished. With the mentioned architecture and process, this LED package herein has three merits, (1) to improve light extraction efficiency: reduce the chance of total internal reflection by the geometry of dome type silicone lens. (2)To enhance the flexibility of LED package design, the die placement location would be constrained by the mold in the traditional package process. (3) Mold-less side-emitting-enhancement silicone lens. Furthermore, two types of cone shape tooling are implemented and compared for side-emitting-enhancement silicone lens. Measurement results show the ratio between the lens high and lens radius could achieve 0.9:1. The view angles of dome type and side-emitting-enhancement LED packaged devices can reach 153° and 180 °, respectively. As using the same brightness grade of LED chip, the luminous flux is increasing 15% as compared the dome type package with the commercial PLCC (Plastic Leaded Chip Carrier) type package. The luminous flux of side-emitting-enhancement LED package decreases 8% as compared with the dome type one.

  9. Unveiling Cebuano Traditional Healing Practices

    Directory of Open Access Journals (Sweden)

    ZachiaRaiza Joy S. Berdon

    2016-02-01

    Full Text Available This study aims to identify the features of Cebuano’s traditional healing practices. Specifically, it also answers the following objectives: analyze traditional healing in Cebuano’s perspectives, explain the traditional healing process practiced in terms of the traditional healers’ belief, and extrapolate perceptions of medical practitioners toward traditional healing. This study made use of qualitative approach, among five traditional healers who performed healing for not less than ten years, in the mountain barangays of Cebu City. These healers served as the primary informants who were selected because of their popularity in healing. The use of open-ended interview in local dialect and naturalistic observation provided a free listing of their verbatim accounts were noted and as primary narratives. Participation in the study was voluntary and participants were interviewed privately after obtaining their consent. The Cebuano traditional healing practices or “panambal” comprise the use of “himolso” (pulse-checking, “palakaw” (petition, “pasubay” (determining what causes the sickness and its possible means of healing, “pangalap” (searching of medicinal plants for “palina” (fumigation, “tayhop” (gentle-blowing, “tutho” (saliva-blowing,“tuob” (boiling, “orasyon” (mystical prayers, “hilot” (massage, and “barang” (sorcery. Though traditional with medical science disapproval, it contributes to a mystical identity of Cebuano healers, as a manifestation of folk Catholicism belief, in order to do a good legacy to the community that needs help. For further study, researchers may conduct further the studies on the: curative effects of medicinal plants in Cebu, psychological effect pulsechecking healed persons by the mananambal, and unmasking the other features of traditional healing.

  10. Aurorae in Australian Aboriginal Traditions

    Science.gov (United States)

    Hamacher, Duane W.

    2013-07-01

    Transient celestial phenomena feature prominently in the astronomical knowledge and traditions of Aboriginal Australians. In this paper, I collect accounts of the Aurora Australis from the literature regarding Aboriginal culture. Using previous studies of meteors, eclipses, and comets in Aboriginal traditions, I anticipate that the physical properties of aurora, such as their generally red colour as seen from southern Australia, will be associated with fire, death, blood, and evil spirits. The survey reveals this to be the case and also explores historical auroral events in Aboriginal cultures, aurorae in rock art, and briefly compares Aboriginal auroral traditions with other global indigenous groups, including the Maori of New Zealand.

  11. Goddess Traditions in Tantric Hinduism

    DEFF Research Database (Denmark)

    Hinduism cannot be understood without the Great Goddess and the goddess-orientated Śākta traditions. The Goddess pervades Hinduism at all levels, from aniconic village deities to high-caste pan-Hindu goddesses to esoteric, tantric goddesses. Nevertheless, the highly influential tantric forms of S...... of South Asian goddess worship have only recently begun to draw scholarly attention. This book addresses the increasing interest in the Great Goddess and the tantric traditions of India by exploring the history, doctrine and practices of the Śākta tantric traditions....

  12. Traditional soyfoods: processing and products.

    Science.gov (United States)

    Golbitz, P

    1995-03-01

    Although soyfoods have been consumed for more than 1000 years, only for the past 15 years have they made an inroad into Western cultures and diets. Soyfoods are typically divided into two categories: nonfermented and fermented. Traditional nonfermented soyfoods include fresh green soybeans, whole dry soybeans, soy nuts, soy sprouts, whole-fat soy flour, soymilk and soymilk products, tofu, okara and yuba. Traditional fermented soyfoods include tempeh, miso, soy sauces, natto and fermented tofu and soymilk products. This paper presents a brief overview of processing techniques used in the manufacture of traditional soyfoods.

  13. Peer-led live research demonstrations: challenging medical student misconceptions about research.

    Science.gov (United States)

    O'Connor, Stuart; Clarke, Alexander Kenneth

    2016-02-01

    Modern health care provision is now fundamentally evidence based, meaning competency in academic medicine is integral to medical training. The Integrated Academic Training pathway provides focussed training in this area at a postgraduate level but no such provision exists at an undergraduate level. A number of peer-led academic societies have emerged across the UK to provide education and support for undergraduates but there is little evidence about the type of peer-led interventions that are effective. We report here the findings of one such peer-led organization, the Warwick Academic Medicine Society. We found that traditional educational interventions, including didactic lectures and small-group teaching, are effective at inspiring students regarding academic medicine but poor at translating this enthusiasm into sustained involvement in research. We find this disparity to be centred on misconceptions amongst students regarding the time and skills required to meaningfully contribute to a research project. Further, we introduce the concept of the Live Research Demonstration (LRD), a novel peer-led educational intervention which aims to address these misconceptions and improve involvement of students in research. Initial pilots of the LRD concept have shown significant promise and we recommend a larger trial across multiple localities to confirm its educational benefits.

  14. Student-led learning: a new teaching paradigm for surgical skills.

    Science.gov (United States)

    Hoogenes, Jen; Mironova, Polina; Safir, Oleg; McQueen, Sydney A; Abdelbary, Hesham; Drexler, Michael; Nousiainen, Markku; Ferguson, Peter; Kraemer, William; Alman, Benjamin; Reznick, Richard K; Sonnadara, Ranil R

    2015-01-01

    Competency-based education and simulation are being used more frequently in surgical skills curricula. We explored a novel student-led learning paradigm, which allows trainees to become more active participants in the learning process while maintaining expert guidance and supervision. Twelve first-year orthopedic residents were randomized to either a student-led (SL) or a traditional instructor-led group during an intensive, month-long, laboratory-based technical skills training course. A rigorous qualitative-description approach was used for analysis. Four prominent themes emerged: instructional style, feedback, peer and instructor collaboration, and self-efficacy. Compared with the instructor-led group, there was more peer assistance, feedback, collaboration, and hands-on and active learning observed in the SL group. The flexible and socially rich nature of the SL learning environment may aid in development of both technical and nontechnical skills early in residency and ultimately privilege later clinical learning. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Demonstration of LED Retrofit Lamps at the Smithsonian American Art Museum, Washington, DC

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Naomi J.; Rosenfeld, Scott M.

    2012-06-22

    This report documents observations and results obtained from a lighting demonstration project conducted under the U.S. Department of Energy GATEWAY Solid-State Lighting (SSL) Technology Demonstration Program at the Smithsonain American Art Museum in Washington, DC. LED Lamp samples were tested in the museum workshop, temporarily installed in a gallery for feedback, and ultimately replaced all traditional incandescent lamps in one gallery of modernist art at the American Art Museum and partially replacing lamps in two galleries at the Musesum's Renwick Gallery. This report describes the selection and testing process, technology challenges, perceptions, economics, energy use, and mixed results of usign LED replacement lamps in art galleries housing national treasures.

  16. Making international links to further interprofessional learning: a student-led initiative for the homeless population.

    Science.gov (United States)

    Goodier, Robyn; Uppal, Shiv; Ashcroft, Harriet

    2015-05-01

    Supporting homeless people to recovery requires interprofessional collaborative responses. In North America interprofessional student groups have supported traditional services to address the needs of homeless populations. We report on the first two years of designing and developing an interprofessional student-led response to support homeless people in the UK. The project began with working in partnership with local statutory and voluntary services; and was affirmed through interviews with local homeless people. The findings identified that many avoided going to the services provided and 90% would welcome clinical services from interprofessional groups of students. The results have led to the launch of project LIGHT (Leicester Initiative Good Health Team) and today interprofessional student groups run health promotion activities for this population.

  17. A comparison of midwife-led care versus obstetrician-led care for low-risk women in Japan.

    Science.gov (United States)

    Iida, Mariko; Horiuchi, Shigeko; Nagamori, Kumiko

    2014-09-01

    Continuity of midwife-led care is recommended in maternity care because of its various positive outcomes. In Japan, midwife-led care is receiving broad attention as well. In order to popularise midwifery care within the entire system of perinatal care in Japan, there is a need to show evidence that continuity of midwife care for women will bring about positive outcomes. The objectives of this study were to compare the health outcomes of women and infants who received midwife-led care with obstetrician-led care in Japan. This was an observational study using non-random purposive sampling with a survey questionnaire. Settings where midwife-led care and obstetrician-led care were chosen by purposive samples. Participants were low-risk women who received antenatal care and delivered a term-singleton-infant at the participating settings during the research period. Measurements were: Women-centred care pregnancy questionnaire, Stein's maternity blues questionnaire, and Edinburgh Postnatal Depression Scale. Midwife-led care was perceived by women to be beneficial and had no adverse outcomes compared to obstetrician-led care. Main findings are: (1) Perception of Women-centred care was higher; (2) Less premature rupture of membranes, and the Apgar scores of the infants were similar; (3) Exclusively breast-feeding during hospitalisation and at one-month postpartum; (4) Stein's maternity blues scale scores was lower in women who received midwife-led care than those who received obstetrician-led care. Continuity of midwife-led care was perceived by women to be beneficial and had no adverse outcomes. Therefore, midwife-led care in low-risk pregnancy could be applicable and recommended. Copyright © 2014 Australian College of Midwives. Published by Elsevier Ltd. All rights reserved.

  18. Quantitative morphological descriptors confirm traditionally ...

    African Journals Online (AJOL)

    SARAH

    2015-09-30

    Sep 30, 2015 ... J. Appl. Biosci. 2015 Quantitative morphological descriptors confirm traditionally classified morphotypes of Pentadesma butyracea Sabine (clusiaceae). 8736. Quantitative morphological descriptors ...... Hijmans RJ, Cameron SE, Parra JL, Jones PG, Jarvis. A, 2004. The WorldClim interpolated global.

  19. [Common household traditional Chinese medicines].

    Science.gov (United States)

    Zhang, Shu-Yuan; Li, Mei; Fu, Dan; Liu, Yang; Wang, Hui; Tan, Wei

    2016-02-01

    With the enhancement in the awareness of self-diagnosis among residents, it's very common for each family to prepare common medicines for unexpected needs. Meanwhile, with the popularization of the traditional Chinese medicine knowledge, the proportion of common traditional Chinese medicines prepared at residents' families is increasingly higher than western medicines year by year. To make it clear, both pre-research and closed questionnaire research were adopted for residents in Chaoyang District, Beijing, excluding residents with a medical background. Based on the results of data, a analysis was made to define the role and influence on the quality of life of residents and give suggestions for relevant departments to improve the traditional Chinese medicine popularization and promote the traditional Chinese medicine market. Copyright© by the Chinese Pharmaceutical Association.

  20. Describing team development within a novel GP-led urgent care centre model: a qualitative study.

    Science.gov (United States)

    Morton, Sarah; Ignatowicz, Agnieszka; Gnani, Shamini; Majeed, Azeem; Greenfield, Geva

    2016-06-23

    Urgent care centres (UCCs) co-located within an emergency department were developed to reduce the numbers of inappropriate emergency department admissions. Since then various UCC models have developed, including a novel general practitioner (GP)-led UCC that incorporates both GPs and emergency nurse practitioners (ENPs). Traditionally these two groups do not work alongside each other within an emergency setting. Although good teamwork is crucial to better patient outcomes, there is little within the literature about the development of a team consisting of different healthcare professionals in a novel healthcare setting. Our aim was therefore to describe staff members' perspectives of team development within the GP-led UCC model. Open-ended semistructured interviews, analysed using thematic content analysis. GP-led urgent care centres in two academic teaching hospitals in London. 15 UCC staff members including six GPs, four ENPs, two receptionists and three managers. Overall participants were positive about the interprofessional team that had developed and recognised that this process had taken time. Hierarchy within the UCC setting has diminished with time, although some residual hierarchical beliefs do appear to remain. Staff appreciated interdisciplinary collaboration was likely to improve patient care. Eight key facilitating factors for the team were identified: appointment of leaders, perception of fair workload, education on roles/skill sets and development of these, shared professional understanding, interdisciplinary working, ED collaboration, clinical guidelines and social interactions. A strong interprofessional team has evolved within the GP-led UCCs over time, breaking down traditional professional divides. Future implementation of UCC models should pro-actively incorporate the eight facilitating factors identified from the outset, to enable effective teams to develop more quickly. Published by the BMJ Publishing Group Limited. For permission to use

  1. Electronic commerce versus traditional commerce

    OpenAIRE

    Dorin Vicentiu Popescu; Manoela Popescu

    2007-01-01

    The internet represents new opportunities for the traditional companies, including the diversification of the given services and also the promotion of the new ones, which are personalized and attractive and they are possible thanks to the information and communication technologies. According to this, the Internet impact, which has allowed the development of a new form of commerce- the commerce via Internet (which is a component of the electronic commerce), against the traditional global comme...

  2. Was the Monetarist Tradition Invented?

    OpenAIRE

    George S. Tavlas

    1998-01-01

    In 1969, Harry Johnson charged that Milton Friedman 'invented' a Chicago oral quantity theory tradition, the idea being that in order to launch a monetarist counter-revolution, Friedman needed to establish a linkage with pre-Keynesian orthodoxy. This paper shows that there was a distinct pre-Keynesian Chicago quantity-theory tradition that advocated increased government expenditure during the Great Depression in order to put money directly into circulation. This policy stance distinguished th...

  3. Little Eyolf and dramatic tradition

    Directory of Open Access Journals (Sweden)

    Roland Lysell

    2015-02-01

    Full Text Available The article criticises an Ibsen tradition who has seen the last scene of Little Eyolf as a reconciliation. Instead, the article discusses the improbability of a happy marriage characterised by social engagement. The play is open but it is hardly probable that Rita, with her erotic desire, and Allmers, whose desire has turned into metaphysics, can be happy together. The arguments refer to inner criteria and the constantly present dramatic tradition.

  4. Monte carlo analysis of multicolour LED light engine

    DEFF Research Database (Denmark)

    Chakrabarti, Maumita; Thorseth, Anders; Jepsen, Jørgen

    2015-01-01

    A new Monte Carlo simulation as a tool for analysing colour feedback systems is presented here to analyse the colour uncertainties and achievable stability in a multicolour dynamic LED system. The Monte Carlo analysis presented here is based on an experimental investigation of a multicolour LED...

  5. Development of thermal LED Model | Kapitonov | Journal of ...

    African Journals Online (AJOL)

    One of the main tasks of modern lighting technology is to increase the reliability of LED technology. In order to solve this problem, it is necessary to ensure an effective cooling of LEDs, since the values of their parameters depend substantially on the temperature of a crystal. This dependence makes a significant effect on the ...

  6. Thermo-mechanical model optimization of HB-LED packaging

    NARCIS (Netherlands)

    Yuan, C.A.; Erinc, M.; Gielen, A.W.J.; Waal, A. van der; Driel, W. van; Zhang, K.

    2011-01-01

    Lighting is an advancing phenomenon both on the technology and on the market level due to the rapid development of the solid state lighting technology. The efforts in improving the efficacy of high brightness LED's (HB-LED) have concentrated on the packaging architecture. Packaging plays a

  7. Tuning the color point of a white LED

    NARCIS (Netherlands)

    Adhikary, Manashee; Meretska, Maryna; Ladovrechis, K.; Fokkema, Wouter K.; Vissenberg, Gilles; Lagendijk, Ad; Ijzerman, W.L.; Vos, Willem L.

    2018-01-01

    White light is conveniently characterized by a color point that is represented on the color space. Color point of white LED is fixed by the design parameters (e.g. Phosphor type and concentration). When the design parameters are chosen, the color point of the white LED cannot be changed. Here, we

  8. Assessment of community led total sanitation uptake in rural Kenya ...

    African Journals Online (AJOL)

    Background: Community Led Total Sanitation (CLTS) is an innovative community led drive to set up pit latrines in rural Kenya with an aim of promoting sustainable sanitation through behaviour change. It's a behaviour change approach based on social capital that triggers households to build pit latrines without subsidy.

  9. Led enhancement in mitochondrial oxidative phosphorylation for hepatectomized rats

    Directory of Open Access Journals (Sweden)

    Orlando de Castro-e-Silva Jr

    2002-01-01

    Full Text Available Recently, the LED (light emitting diode developed by the Optics Group of IFSC-USP has been used instead of laser for the treatment of skin tumors by the PDT (Photodinamic Therapy because of its low operational cost compared to the use of a laser. In this paper we investigate the effect of LED light on oxidative phosphorylation during liver regeneration after partial hepatectomy. Twenty-four male Wistar rats (250 g were kept in identical housing units on a 12-hour light/12 hour dark cycle. The LED 10 group was exposed to LED at 638 nm (10 J/cm² for 3 minutes. Seventy percent partial hepatectomy was performed in the LED 10 and HPC (Partial Hepatectomy-Control. A sham-operated group (C was used for control. Twenty four hours after the procedure, LED 10, HPC and control animals were sacrificed. Samples of liver tissue were used for the mitochondrial respiration assay. Statistical comparisons of the groups were performed by analysis of variance (ANOVA, followed by the Bonferroni post-test. Probability values less than 0.05 were considered to be statistically significant. the phosphorylation index (FI for the LED 10 group was higher than that for the HPC group and for the sham group (p 0.05. In the present study we noted an effective interaction between LED light and hepatic mitochondria, with an increased phosphorylation rate for the latter.

  10. Transport of Light Through White-LED Phosphor Plates

    NARCIS (Netherlands)

    Meretska, Maryna; Thyrrestrup Nielsen, Henri; Lagendijk, Aart; Tukker, Teus; Mosk, Allard; IJzerman, Wilbert; Vos, Willem L.; Di Bartolo, Baldassare; Collins, John; Silvestri, Luciano

    2017-01-01

    Energy efficient generation of white light has become an important societal issue in recent years. The technology of white-light emitting diodes (LEDs) is one of the main directions (Akasaki I, Amano H, Nakamura S, Blue LEDs – filling the world with new light, http://www.nobelprize.org/, 2014;

  11. Transport of light through white-LED phosphor plates

    NARCIS (Netherlands)

    Meretska, Maryna; Thyrrestrup, H.; Lagendijk, Ad; Tukker, T. W.; Mosk, A. P.; IJzerman, W. L.; Vos, Willem L.

    2017-01-01

    Energy efficient generation of white light has become an important societal issue in recent years. The technology of white-light emitting diodes (LEDs) is one of the main directions (Akasaki I, Amano H, Nakamura S, Blue LEDs – filling the world with new light, http://www.nobelprize.org/, 2014;

  12. LED roadway lighting, volume 2 : field evaluations and software comparisons.

    Science.gov (United States)

    2012-10-01

    The use of light-emitting diodes (LEDs) for roadway lighting can potentially save energy costs and reduce the frequency of maintenance. The objective of this study is to explore the current state of the art in LED roadway lighting technology. Three s...

  13. The WIMSE-E module W-LED

    International Nuclear Information System (INIS)

    Roth, M.J.

    1992-06-01

    This report describes the WIMS-E edit module W-LED. W-LED sets up a library of cross section and other nuclear data for a set of materials for subsequent use in a whole reactor program such as PANTHER. (author)

  14. Thermal analysis of LED lamps for optimal driver integration

    NARCIS (Netherlands)

    Perpiñà, X.; Werkhoven, R.J.; Vellvehi, M.; Jakovenko, J.; Jordà, X.; Kunen, J.M.G.; Bancken, P.; Bolt, P.J.

    2015-01-01

    This paper studies the thermal influence of a light-emitting diode (LED) driver on a retrofit LED lamp, also reporting on a procedure for its thermal characterization and multiscale modeling. In this analysis, temperature is measured by infrared thermography and monitoring specific locations with

  15. Student-Led Parent Conferences: A Model for Teaching Responsibility.

    Science.gov (United States)

    Guyton, Jane M.; Fielstein, Lynda L.

    1989-01-01

    Describes program in which elementary school students lead parent-teacher conferences, shares authors' experiences with the student-led conferences, and discusses how the process has fostered student responsibility. Describes results of informal study that support the student-led conference. (NB)

  16. Low Cost Lithography Tool for High Brightness LED Manufacturing

    Energy Technology Data Exchange (ETDEWEB)

    Andrew Hawryluk; Emily True

    2012-06-30

    The objective of this activity was to address the need for improved manufacturing tools for LEDs. Improvements include lower cost (both capital equipment cost reductions and cost-ofownership reductions), better automation and better yields. To meet the DOE objective of $1- 2/kilolumen, it will be necessary to develop these highly automated manufacturing tools. Lithography is used extensively in the fabrication of high-brightness LEDs, but the tools used to date are not scalable to high-volume manufacturing. This activity addressed the LED lithography process. During R&D and low volume manufacturing, most LED companies use contact-printers. However, several industries have shown that these printers are incompatible with high volume manufacturing and the LED industry needs to evolve to projection steppers. The need for projection lithography tools for LED manufacturing is identified in the Solid State Lighting Manufacturing Roadmap Draft, June 2009. The Roadmap states that Projection tools are needed by 2011. This work will modify a stepper, originally designed for semiconductor manufacturing, for use in LED manufacturing. This work addresses improvements to yield, material handling, automation and throughput for LED manufacturing while reducing the capital equipment cost.

  17. Shortest exposure time possible with LED curing lights

    NARCIS (Netherlands)

    Busemann, I.; Lipke, C.; Schattenberg, A.V.M.B.; Willershausen, B.; Ernst, C.P.

    2011-01-01

    PURPOSE: To investigate the shortest exposure time of different light emitting diode (LED)-curing devices for different resin composites in a clinically relevant laboratory model. METHODS: Nine LED curing devices (Bluephase, Bluephase 16i, Bluephase G2, Bluephase 20i/Ivoclar Vivadent, DEMI/sds Kerr,

  18. The effect of LED illumination on endodontic biofilms

    DEFF Research Database (Denmark)

    Markvart, Merete

    nm) and UVC (266nm) region. The PDT was applied using the commercial product Fotosan®. The UV LEDs were able to eliminate the E. faecalis biofilm while the PDT was only able to make a reduction in the total number of viable cells. UV LEDs may improve disinfection procedures during root canal...

  19. Luminous flux and colour maintenance investigation of integrated LED lamps

    DEFF Research Database (Denmark)

    Corell, Dennis Dan; Thorseth, Anders; Dam-Hansen, Carsten

    2014-01-01

    This article will present an investigation of the luminous flux and colour maintenance of white LED based retrofit lamps. The study includes 23 different types of integrated LED lamps, covering 18 directional and 5 non-directional. Luminous flux and colour data for operation up to 20000 h has been...

  20. Design of LED lamps | Ashryatov | Journal of Fundamental and ...

    African Journals Online (AJOL)

    The variant of the lighting system energy efficiency increase with luminaires and linear fluorescent lamps is considered. In the proposed variant, the fluorescent lamps and start regulating devices are replaced with linear LED modules. In order to reduce the glossiness of a luminaire, the LED modules must be covered with ...

  1. Improved power quality based high brightness LED lamp driver ...

    African Journals Online (AJOL)

    This paper deals with a power factor corrected (PFC) improved power quality based LED lamp driver. The proposed driver consists of a PFC Cuk DC-DC converter which operates in continuous conduction mode (CCM) to improve the power quality at input AC mains. The design, modeling and simulation of an 18W LED (six ...

  2. The Living Indian Critical Tradition

    Directory of Open Access Journals (Sweden)

    Vivek Kumar Dwivedi

    2010-11-01

    Full Text Available This paper attempts to establish the identity of something that is often considered to be missing – a living Indian critical tradition. I refer to the tradition that arises out of the work of those Indians who write in English. The chief architects of this tradition are Sri Aurobindo, C.D. Narasimhaiah, Gayatri Chakravorty Spivak and Homi K. Bhabha. It is possible to believe that Indian literary theories derive almost solely from ancient Sanskrit poetics. Or, alternatively, one can be concerned about the sad state of affairs regarding Indian literary theories or criticism in English. There have been scholars who have raised the question of the pathetic state of Indian scholarship in English and have even come up with some positive suggestions. But these scholars are those who are ignorant about the living Indian critical tradition. The significance of the Indian critical tradition lies in the fact that it provides the real focus to the Indian critical scene. Without an awareness of this tradition Indian literary scholarship (which is quite a different thing from Indian literary criticism and theory as it does not have the same impact as the latter two do can easily fail to see who the real Indian literary critics and theorists are.

  3. Indoor visual positioning system using LED and mobile phone

    Science.gov (United States)

    Gong, Yingkui; Shi, Zhengfa; Wang, Yuqi

    2016-01-01

    An indoor visual positioning system is proposed, which using four or more LED ceiling lamps and a mobile phone. A 4*4 photodiode array is attached to the mobile phone to receive the three-dimensional coordinates of the LED lamps via visible light communication, and the front camera of the mobile phone is used to receive the high resolution image of the LED lamps. The mobile phone's three-dimensional coordinates can be determined by matching the spot information and three-dimensional coordinates of the LED lamps with the image information provided by the mobile phone. An improved collinear equation model is proposed to build the mapping relationship between the three-dimensional coordinates of the LED lamps and the image information acquired by the front camera. A semi-physical simulation has been conducted and analyzed. The positioning scheme is proved to be valid and the positioning accuracy is up to decimeter level.

  4. Investigation of irradiance efficiency for LED phototherapy with different arrays

    Science.gov (United States)

    Chen, Hsi-Chao; Wu, Guo-Yang

    2010-12-01

    Red and yellow light emitting diodes (LEDs) are currently utilized as lighting sources during LED phototherapy. These LEDs were arranged on a disk with an external diameter of 70 mm with different arrays — radial, rhombus, square radial, and square rhombus arrays. The radial and square radial arrays had better irradiance efficiency than rhombus and square rhombus arrays by optical simulation. Additionally, the radial array had 76 sets of LEDs, but the square radial array had 100 sets. Thus, a mockup sample of radial array phototherapy was constructed for performance tests. The mixture efficiency of the radial array was observed at distances of 1-100 mm and lighting was well mixed when distance exceeded 50 mm by optical simulation. Irradiance variation with angle was approximated by experiment and theory at a treatment distance of 50 mm and 100 mm using the phototherapy mockup. The radial array was one good choice for LED phototherapy.

  5. The LED monitoring system of the PHOENICS experiment

    International Nuclear Information System (INIS)

    Urban, D.

    1991-07-01

    The PHOENICS experiment at ELSA uses a LED monitoring system to control pulse height and time measurement with scintillation counters. A green LED is mounted at the light guide of each of the 304 involved photomultiplier tubes. The LEDs are driven by fast voltage pulses of 5 ns FWHM width and about 20 V amplitude. Simulation of single events is possible by computer controlled switching of individual LEDs. In order to correct for the temperature dependence of the LED intensity an automatic temperature recording system was coupled to the computer. This monitor system allows to control the pulse height and time measurement with an accuracy of about 2% and 100 ps respectively. (orig.) [de

  6. Teaching Vocabulary to Preschoolers with Disabilities Using Adult-Child Shared Bookreading: A Comparison of Traditional and Electronic Books

    Science.gov (United States)

    Rhodehouse, Sara Bernice

    2013-01-01

    This study sought to validate adult-child shared storybook reading as a method for teaching target vocabulary words to preschool children with disabilities. The Vocabulary Learning through Books (VLTB) instructional procedure incorporates, adult-child book reading, questioning during reading requiring the child to answer with a target word, and…

  7. Progress in extremely high brightness LED-based light sources

    Science.gov (United States)

    Hoelen, Christoph; Antonis, Piet; de Boer, Dick; Koole, Rolf; Kadijk, Simon; Li, Yun; Vanbroekhoven, Vincent; Van De Voorde, Patrick

    2017-09-01

    Although the maximum brightness of LEDs has been increasing continuously during the past decade, their luminance is still far from what is required for multiple applications that still rely on the high brightness of discharge lamps. In particular for high brightness applications with limited étendue, e.g. front projection, only very modest luminance values in the beam can be achieved with LEDs compared to systems based on discharge lamps or lasers. With dedicated architectures, phosphor-converted green LEDs for projection may achieve luminance values up to 200-300 Mnit. In this paper we report on the progress made in the development of light engines based on an elongated luminescent concentrator pumped by blue LEDs. This concept has recently been introduced to the market as ColorSpark High Lumen Density LED technology. These sources outperform the maximum brightness of LEDs by multiple factors. In LED front projection, green LEDs are the main limiting factor. With our green modules, we now have achieved peak luminance values of 2 Gnit, enabling LED-based projection systems with over 4000 ANSI lm. Extension of this concept to yellow and red light sources is presented. The light source efficiency has been increased considerably, reaching 45-60 lm/W for green under practical application conditions. The module architecture, beam shaping, and performance characteristics are reviewed, as well as system aspects. The performance increase, spectral range extensions, beam-shaping flexibility, and cost reductions realized with the new module architecture enable a breakthrough in LED-based projection systems and in a wide variety of other high brightness applications.

  8. Designing low cost LED display for the billboard

    Science.gov (United States)

    Hong, Yi-Jian; Uang, Chii-Maw; Wang, Ping-Chieh; Ho, Zu-Sheng

    2011-10-01

    With quickly advance of the computer, microelectronics and photonics technologies, LED display panel becomes a new electronic advertising media. It can be used to show any information whatever characters or graphics. Most LED display panels are built of many Light-Emitting Diodes arranged in a matrix form. The display has many advantages such as low power, low cost, long life and high definition. Because the display panel is asked to show rich color, the LED display panel's driving system becomes very complex. The design methodology of LED display panel's driver becomes more and more important to meet the market requirements. Cost is always the most important issue in public market domain. In this paper, we report a design methodology of LED display panel's driver based on the microprocessor control unit (MCU) system and LED display controller IC, HT1632C, to control three colors, RGB, color LED display panel and the modular panel size is 24*16 in matrix form. The HT1632C is a memory mapping LED display controller, it can be used on many applications, such as digital clock, thermometer, counter, voltmeter or other instrumentation readouts. Three pieces of HT1632C are used to drive a 24*16 RGB LED display panel, in our design case. Each HT163C chip is used to control one of the R, G and B color. As the drive mode is driven in DC mode, the RGB display panel can create and totally of seven colors under the control of MCU. The MCU generates the control signal to drive HT1632C. In this study, the software design methodology is adopted with dynamic display principle. When the scan frequency is 60Hz, LED display panel will get the clear picture and be able to display seven colors.

  9. Prediction of L70 lumen maintenance and chromaticity for LEDs using extended Kalman filter models

    Energy Technology Data Exchange (ETDEWEB)

    Lall, Pradeep; Wei, Junchao; Davis, Lynn

    2013-09-30

    Solid-state lighting (SSL) luminaires containing light emitting diodes (LEDs) have the potential of seeing excessive temperatures when being transported across country or being stored in non-climate controlled warehouses. They are also being used in outdoor applications in desert environments that see little or no humidity but will experience extremely high temperatures during the day. This makes it important to increase our understanding of what effects high temperature exposure for a prolonged period of time will have on the usability and survivability of these devices. Traditional light sources “burn out” at end-of-life. For an incandescent bulb, the lamp life is defined by B50 life. However, the LEDs have no filament to “burn”. The LEDs continually degrade and the light output decreases eventually below useful levels causing failure. Presently, the TM-21 test standard is used to predict the L70 life of LEDs from LM-80 test data. Several failure mechanisms may be active in a LED at a single time causing lumen depreciation. The underlying TM-21 Model may not capture the failure physics in presence of multiple failure mechanisms. Correlation of lumen maintenance with underlying physics of degradation at system-level is needed. In this paper, Kalman Filter (KF) and Extended Kalman Filters (EKF) have been used to develop a 70-percent Lumen Maintenance Life Prediction Model for LEDs used in SSL luminaires. Ten-thousand hour LM-80 test data for various LEDs have been used for model development. System state at each future time has been computed based on the state space at preceding time step, system dynamics matrix, control vector, control matrix, measurement matrix, measured vector, process noise and measurement noise. The future state of the lumen depreciation has been estimated based on a second order Kalman Filter model and a Bayesian Framework. The measured state variable has been related to the underlying damage using physics-based models. Life

  10. Tradition?! Traditional Cultural Institutions on Customary Practices in Uganda

    Directory of Open Access Journals (Sweden)

    Joanna R. Quinn

    2014-01-01

    Full Text Available This contribution traces the importance of traditional institutions in rehabilitating societies in general terms and more particularly in post-independence Uganda. The current regime, partly by inventing “traditional” cultural institutions, partly by co-opting them for its own interests, contributed to a loss of legitimacy of those who claim responsibility for customary law. More recently, international prosecutions have complicated the use of customary mechanisms within such societies. This article shows that some traditional and cultural leaders continue to struggle to restore their original institutions, some having taken the initiative of inventing new forms of engaging with society. Uganda is presented as a test case for the International Criminal Court’s ability to work with traditional judicial institutions in Africa.

  11. A transparent look at the measurement and application of colour rendering in the use of LED light sources

    Science.gov (United States)

    Leuschner, F. W.; Van Der Westhuyzen, J. G. J.

    2014-06-01

    The technology for the measurement of colour rendering and colour quality is not new, but many parameters related to this issue are currently changing. A number of standard methods were developed and are used by different specialty areas of the lighting industry. CIE 13.3 has been the accepted standard implemented by many users and used for many years. Light-emitting Diode (LED) technology moves at a rapid pace and, as this lighting source finds wider acceptance, it appears that traditional colour-rendering measurement methods produce inconsistent results. Practical application of various types of LEDs yielded results that challenged conventional thinking regarding colour measurement of light sources. Recent studies have shown that the anatomy and physiology of the human eye is more complex than formerly accepted. Therefore, the development of updated measurement methodology also forces a fresh look at functioning and colour perception of the human eye, especially with regard to LEDs. This paper includes a short description of the history and need for the measurement of colour rendering. Some of the traditional measurement methods are presented and inadequacies are discussed. The latest discoveries regarding the functioning of the human eye and the perception of colour, especially when LEDs are used as light sources, are discussed. The unique properties of LEDs when used in practical applications such as luminaires are highlighted.

  12. Peer-led and professional-led group interventions for people with co-occurring disorders: a qualitative study.

    Science.gov (United States)

    Pallaveshi, Luljeta; Balachandra, Krishna; Subramanian, Priya; Rudnick, Abraham

    2014-05-01

    This pilot study evaluated the experience of people with co-occurring disorders (mental illness and addiction) in relation to peer-led and professional-led group interventions. The study used a qualitative (phenomenological) approach to evaluate the experience of a convenience sample of 6 individuals with co-occurring disorders who participated in up to 8 sessions each of both peer-led and professional-led group interventions (with a similar rate of attendance in both groups). The semi-structured interview data were coded and thematically analyzed. We found 5 themes within and across the 2 interventions. In both groups, participants experienced a positive environment and personal growth, and learned, albeit different things. They were more comfortable in the peer-led group and acquired more knowledge and skills in the professional-led group. Offering both peer-led and professional-led group interventions to people with co-occurring disorders may be better than offering either alone.

  13. Novel thin-GaN LED structure adopted micro abraded surface to compare with conventional vertical LEDs in ultraviolet light

    Science.gov (United States)

    Chiang, Yen Chih; Lin, Chien Chung; Kuo, Hao Chung

    2015-04-01

    In this study, novel thin-GaN-based ultraviolet light-emitting diodes (NTG-LEDs) were fabricated using wafer bonding, laser lift-off, dry etching, textured surface, and interconnection techniques. Placing PN electrodes on the same side minimized the absorption caused by electrodes in conventional vertical injection light-emitting diodes (V-LEDs) and the current spreading was improved. The light output power (700 mA) of the NTG-LEDs was enhanced by 18.3% compared with that of the V-LEDs, and the external quantum efficiency (EQE) of the NTG-LEDs was also relatively enhanced by 20.0% compared with that of a reference device. When the current operations were 1,500 mA, the enhancements of the light output power and EQE were 27.4% and 27.2%, respectively. Additionally, the efficiency droop was improved by more than 15% at the same current level.

  14. Advocate program for healthy traditional houses, Ume Kbubu, in a Timor community: preserving traditional behavior and promoting improved health outcomes.

    Science.gov (United States)

    Prasodjo, Rachmalina; Musadad, D Anwar; Muhidin, Salut; Pardosi, Jerico; Silalahi, Maria

    2015-01-01

    Families in the Timor society of Indonesia have customarily used traditional houses, called Ume Kbubu, for confinement practices of a newborn baby and the mother during the first 40 days after birth. The practice, known as Sei (smoke) tradition, involves retaining heat, which is believed to foster healing, inside the house by continuously burning a wood burning stove. Exacerbated by inadequate ventilation in the traditional house, this practice results in poor indoor air quality and negatively affects the health of the mother and baby. Preliminary findings from a baseline study conducted in 2009 identified high levels of indoor air pollution in Ume Kbubu where mothers practiced the Sei tradition. Many respondents expressed that they suffered from respiratory health problems during the practice. On the basis of those results, a follow-up study was conducted in 2011 to develop and test a communication-focused behavior change intervention that would foster conversion of traditional houses into healthy Ume Kbubu and promote changes to traditional practices for better health outcomes. The study suggests that redesigning an Ume Kbubu house could promote better air quality inside the house and involving the community in the health intervention program led to positive changes in the Sei practice (i.e., decreasing the Sei period's length from 40 days to 4 days on average and attempting to reduce household air pollution). The study resulted in several recommendations in relation to sustained transformation to improve health behaviors.

  15. Dome diagnostics system of optical parameters and characteristics of LEDs

    Science.gov (United States)

    Peretyagin, Vladimir S.; Pavlenko, Nikita A.

    2017-09-01

    Scientific and technological progress of recent years in the production of the light emitting diodes (LEDs) has led to the expansion of areas of their application from the simplest systems to high precision lighting devices used in various fields of human activity. However, development and production (especially mass production) of LED lighting devices are impossible without a thorough analysis of its parameters and characteristics. There are many ways and devices for analysis the spatial, energy and colorimetric parameters of LEDs. The most methods are intended for definition only one parameter (for example, luminous flux) or one characteristic (for example, the angular distribution of energy or the spectral characteristics). Besides, devices used these methods are intended for measuring parameters in only one point or plane. This problem can be solved by using a dome diagnostics system of optical parameters and characteristics of LEDs, developed by specialists of the department OEDS chair of ITMO University in Russia. The paper presents the theoretical aspects of the analysis of LED's spatial (angular), energy and color parameters by using mentioned of diagnostics system. The article also presents the results of spatial), energy and color parameters measurements of some LEDs brands.

  16. Effect of electrophotographic processes on print quality in LED printers

    Science.gov (United States)

    Wyhof, John R.

    1990-08-01

    The advantage of LED electrophotographic page printers is closely linked to the the process parameters of the printer. The electrical and mechanical processes and material properties were analyzed with respect to the affect on the print quality. Most critical to the print quality for the LED array printer is the constancy of the light intensity since the elements in the array are each independent light sources. It was found that the spot size can change significantly if the light intensity varies. Halftone printing uses the spot size to space size ratio to create the grayscale. The light intensity variation between elements can be 20 in non-compensated LED head arrays. If the need for light intensity compensation can be eliminated then a significant cost reduction in the LED head can be achieved. However the parameters of the basic electrophotographic processes must be carefully selected to assure a constant spot size and optimum print quality. The development method toner properties and the portion of the photoreceptor discharge curve used have the strongest influence on the spot size and halftone print quality. Transfer fusing and mechanical parameters have minimal effect. 1. LED PRINTING PROCESS The advantages of the LED printing process for high speed electrophotographic printers are well known. 1 Recently several printer manufacturers have introduced electrophotographic LED printers in the lower speed range. When compared to the scanning laser beam or liquid crystal

  17. Reliability test and failure analysis of high power LED packages

    Science.gov (United States)

    Zhaohui, Chen; Qin, Zhang; Kai, Wang; Xiaobing, Luo; Sheng, Liu

    2011-01-01

    A new type application specific light emitting diode (LED) package (ASLP) with freeform polycarbonate lens for street lighting is developed, whose manufacturing processes are compatible with a typical LED packaging process. The reliability test methods and failure criterions from different vendors are reviewed and compared. It is found that test methods and failure criterions are quite different. The rapid reliability assessment standards are urgently needed for the LED industry. 85 °C/85 RH with 700 mA is used to test our LED modules with three other vendors for 1000 h, showing no visible degradation in optical performance for our modules, with two other vendors showing significant degradation. Some failure analysis methods such as C-SAM, Nano X-ray CT and optical microscope are used for LED packages. Some failure mechanisms such as delaminations and cracks are detected in the LED packages after the accelerated reliability testing. The finite element simulation method is helpful for the failure analysis and design of the reliability of the LED packaging. One example is used to show one currently used module in industry is vulnerable and may not easily pass the harsh thermal cycle testing.

  18. [Study on the safety of blue light leak of LED].

    Science.gov (United States)

    Shen, Chong-Yu; Xu, Zheng; Zhao, Su-Ling; Huang, Qing-Yu

    2014-02-01

    In this paper, the blue light properties of LED illumination devices have been investigated. Against the status quo of China's LED lighting, we measured the spectrum component of LED lamps and analyzed the photobiological safety under the current domestic and international standards GB/T 20145-2006/CIE S009/E: 2002 and IEC62471: 2006 standards as well as CTL-0744_2009-laser resolution, which provides the reference to the manufacture of LED lighting lamps as well as related safety standards and laws. If the radiance intensity of blue light in LED is lower than 100 W x m(-2) x Sr(-1), there is no harm to human eyes. LEDs will not cause harm to human eyes under normal use, but we should pay attention to the protection of special populations (children), and make sure that they avoid looking at a light source for a long time. The research has found that the blue-rich lamps can affect the human rule of work and rest, and therefore, the LED lamps with color temperature below 4 000 K and color rendering index of 80 are suitable for indoor use. At the same time, the lamps with different parameters should be selected according to the different distances.

  19. Traditional botanical medicine: an introduction.

    Science.gov (United States)

    Rosenbloom, Richard A; Chaudhary, Jayesh; Castro-Eschenbach, Diane

    2011-01-01

    The role of traditional medicine in the well-being of mankind has certainly journeyed a long way. From an ancient era, in which knowledge was limited to a few traditional healers and dominated by the use of whole plants or crude drugs, the science has gradually evolved into a complete healthcare system with global recognition. Technologic advancements have facilitated traditional science to deliver numerous breakthrough botanicals with potency equivalent to those of conventional drugs. The renewed interest in traditional medicine is mainly attributed to its ability to prevent disease, promote health, and improve quality of life. Despite the support received from public bodies and research organizations, development of botanical medicines continues to be a challenging process. The present article gives a summarized description of the various difficulties encountered in the development and evaluation of botanical drugs, including isolation of active compounds and standardization of plant ingredients. It indicates a future direction of traditional medicine toward evidence-based evaluation of health claims through well-controlled safety and efficacy studies.

  20. LED lamps in shipboard lighting systems: Aspects of electromagnetic compatibility

    Directory of Open Access Journals (Sweden)

    Beley V. F.

    2016-12-01

    Full Text Available Trends in the development of different types of light sources and their energy characteristics have been described in the paper. Analysis of regulatory documents has been given. The results of experimental studies of a number of modern LED lamps have been described. Investigation has been made for a number of LED lamps produced by Philips, Xavax and Melitec. The experimental data have been obtained with the complex of devices: the dual-channel oscilloscope (GDS-71042, the power quality analyzer (Fluke-434 and the multi-function device EcoLight-01 (light-, pulse- and luminance meter. It has been shown that operation of LED lamps is characterized by emission of higher current harmonics and reactive power consumption, which depends on the type and design of the lamp driver. It has been found that the value of luminance created by LED lamps in case of acceptable (for ships prolonged deviation of voltage (–10 % is reduced by 3 %; in case of permissible short-term voltage deviation (–20 % luminance is reduced by 7 %. For incandescent lamps this indicator is characterized by a decrease in luminance by 40 % and 60 %, respectively. Despite the low sensitivity to voltage changes (in comparison with other types of lamps, the operation of LED lamps is also associated with the appearance of flicker. Absence of limitations for fluctuations of the light flux in shipboard lighting systems and imperfection of methods for determining the flicker make it difficult to ensure electromagnetic compatibility of LED lamps. Therefore due to reliability, environmental friendliness, energy efficiency and lumen maintenance LED lamps have prospects for introduction into shipboard lighting systems. However, to ensure electromagnetic compatibility of LED lighting systems it is necessary to conduct a detailed study of energy characteristics of LED lamps and to develop appropriate regulatory requirements and technical solutions.

  1. Evaluating UV-C LED disinfection performance and ...

    Science.gov (United States)

    This study evaluated ultraviolet (UV) light emitting diodes (LEDs) emitting at 260 nm, 280 nm, and the combination of 260|280 nm together for their efficacy at inactivating Escherichia. coli, MS2 coliphage, human adenovirus type 2 (HAdV2), and Bacillus pumilus spores; research included an evaluation of genomic damage. Inactivation by the LEDs was compared with the efficacy of conventional UV sources, the low-pressure (LP) and medium-pressure (MP) mercury vapor lamps. The work also calculated the electrical energy per order of reduction of the microorganisms by the five UV sources.For E. coli, all five UV sources yielded similar inactivation rates. For MS2 coliphage, the 260 nm LED was most effective. For HAdV2 and B. pumilus, the MP UV lamp was significantly more effective than the LP UV and UVC LED sources. When considering electrical energy per order of reduction, the LP UV lamp was the most efficient for E. coli and MS2, and the MPUV and LPUV were equally efficient for HAdV2 and B. pumilus spores. Among the UVC LEDs, the 280 nm LED unit required the least energy per log reduction of E. coli and HAdV2. The 280 nm and 260|280 nm LED units were equally efficient per log reduction of B. pumilus spores, and the 260 nm LED unit required the lowest energy per order of reduction of MS2 coliphage. The combination of the 260 nm and 280 nm UV LED wavelengths was also evaluated for potential synergistic effects. No dual-wavelength synergy was detected for inactivation of

  2. LOW-COST LED LUMINAIRE FOR GENERAL ILLUMINATION

    Energy Technology Data Exchange (ETDEWEB)

    Lowes, Ted

    2014-07-31

    During this two-year Solid-State Lighting (SSL) Manufacturing R&D project Cree developed novel light emitting diode (LED) technologies contributing to a cost-optimized, efficient LED troffer luminaire platform emitting at ~3500K correlated color temperature (CCT) at a color rendering index (CRI) of >90. To successfully achieve program goals, Cree used a comprehensive approach to address cost reduction of the various optical, thermal and electrical subsystems in the luminaire without impacting performance. These developments built on Cree’s high- brightness, low-cost LED platforms to design a novel LED component architecture that will enable low-cost troffer luminaire designs with high total system efficacy. The project scope included cost reductions to nearly all major troffer subsystems as well as assembly costs. For example, no thermal management components were included in the troffer, owing to the optimized distribution of compact low- to mid-power LEDs. It is estimated that a significant manufacturing cost savings will result relative to Cree’s conventional troffers at the start of the project. A chief project accomplishment was the successful development of a new compact, high-efficacy LED component geometry with a broad far-field intensity distribution and even color point vs. emission angle. After further optimization and testing for production, the Cree XQ series of LEDs resulted. XQ LEDs are currently utilized in Cree’s AR series troffers, and they are being considered for use in other platforms. The XQ lens geometry influenced the independent development of Cree’s XB-E and XB-G high-voltage LEDs, which also have a broad intensity distribution at high efficacy, and are finding wide implementation in Cree’s omnidirectional A-lamps.

  3. Éalonnage de sources lumineuses de type LED

    DEFF Research Database (Denmark)

    Durix, Bastien; Quéau, Yvain; Lucas, Tom

    We describe three calibration methods of a LED (light-emitting diode), in order to apply photometric stereo to a scene illuminated by LEDs. The most accurate of these methods will allow us to obtain very realistic 3D models. Nevertheless, the scene must remain still during the whole shooting...... sequence. We thus extend this method to a LED model which takes into account the color of the light flow. This will allow us to perform photometric stereo from a unique colored image of a scene, if it is simultaneously illuminated with three colored light flows....

  4. The Role of Documentation in Practice-Led Research

    OpenAIRE

    Nithikul Nimkulrat

    2007-01-01

    Practice-led research in the field of art and design usually involves a study of the interplay between a researcher-practitioner and her artistic work in process. This article seeks to illustrate that documentation of art practice can be a means to record that interplay and it can be used as relevant material in practice-led research. The article will present an account of documentation in practice-led research highlighting two principal aspects: phases of documentation and the role of docume...

  5. Adapting research activity: AHRC review of practice-led research

    OpenAIRE

    Till, J; Mottram, J; Rust, C

    2005-01-01

    In 2005 the Arts and Humanities Research Council initiated a review of practice-led research in art, design and architecture. The purpose of the review was to develop a ‘comprehensive map of recent and current research activity in the area’. What quickly became obvious to the team that won the bid to run the review (led by the three authors) was that to map activity one first had to attempt to define it. The term ‘practice-led research’ means many different things to different people and so i...

  6. Energy efficient LED layout optimization for near-uniform illumination

    Science.gov (United States)

    Ali, Ramy E.; Elgala, Hany

    2016-09-01

    In this paper, we consider the problem of designing energy efficient light emitting diodes (LEDs) layout while satisfying the illumination constraints. Towards this objective, we present a simple approach to the illumination design problem based on the concept of the virtual LED. We formulate a constrained optimization problem for minimizing the power consumption while maintaining a near-uniform illumination throughout the room. By solving the resulting constrained linear program, we obtain the number of required LEDs and the optimal output luminous intensities that achieve the desired illumination constraints.

  7. Optimized Phosphors for Warm White LED Light Engines

    Energy Technology Data Exchange (ETDEWEB)

    Setlur, Anant; Brewster, Megan; Garcia, Florencio; Hill, M. Christine; Lyons, Robert; Murphy, James; Stecher, Tom; Stoklosa, Stan; Weaver, Stan; Happek, Uwe; Aesram, Danny; Deshpande, Anirudha

    2012-07-30

    The objective of this program is to develop phosphor systems and LED light engines that have steady-state LED efficacies (using LEDs with a 60% wall-plug efficiency) of 105–120 lm/W with correlated color temperatures (CCT) ~3000 K, color rendering indices (CRI) >85, <0.003 distance from the blackbody curve (dbb), and <2% loss in phosphor efficiency under high temperature, high humidity conditions. In order to reach these goals, this involves the composition and processing optimization of phosphors previously developed by GE in combination with light engine package modification.

  8. Comparative life cycle assessment of LED lighting products

    OpenAIRE

    Casamayor, JL; Su, D; Ren, Z

    2017-01-01

    LED lighting products used in lighting applications and their subsequent environmental impact are growing rapidly. However, there are no in-depth updated studies that show how to assess and compare them for eco-design purposes. This research aims to add insights in this area to inform eco-design by assessing and comparing the environmental impact of a new LED eco-lighting product with an existing LED lighting product. A cradle to grave Life Cycle assessment (LCA) was conducted using ReCiPe Mi...

  9. High Output LED-Based Profile Lighting Fixture

    DEFF Research Database (Denmark)

    Török, Lajos; Beczkowski, Szymon; Munk-Nielsen, Stig

    2011-01-01

    Recent developments in power light emitting diode (LED) industry have made LEDs suitable for being efficiently used in high intensity lighting fixtures instead of the commonly used high intensity discharge (HID) lamps. A high output LEDbased profile-light fixture is presented in this paper...... the grid and delivers the required voltage to the LEDdriver which is a dual interleaved buck converter. Twelve highpower CBT-90 LEDs have been connected in a 4xRGBconfiguration to deliver high output of saturated colors without the need for subtractive color filters. More than 6000 lm of fixture light...

  10. Iluminación LED. Un arma de doble filo

    OpenAIRE

    Sánchez de Miguel, Alejandro

    2004-01-01

    La iluminación LED es el futuro de la iluminación. Sin embargo, como toda tecnología, puede usarse de manera correcta o incorrecta. En el caso de los LED, el abaratamiento de la producción de luz podría provocar un aumento descontrolado de la Contaminación lumínica. Por otro, el uso correcto de los LED podría ser la solución al mismo mal por su capacidad de encendido casi instantáneo.

  11. High power LEDs - technology status and market applications

    International Nuclear Information System (INIS)

    Steranka, F.M.; Bhat, J.; Collins, D.; Cook, L.; Craford, M.G.; Fletcher, R.; Gardner, N.; Grillot, P.; Goetz, W.; Keuper, M.; Khare, R.; Kim, A.; Krames, M.; Harbers, G.; Ludowise, M.; Martin, P.S.; Misra, M.; Mueller, G.; Mueller-Mach, R.; Rudaz, S.; Shen, Y.C.; Steigerwald, D.; Subramanya, S.; Trottier, T.; Wierer, J.J.

    2002-01-01

    High power light emitting diodes (LEDs) continue to increase in output flux with the best III-nitride based devices today emitting over 150 lm of white, cyan, or green light. The key design features of such products will be covered with special emphasis on power packaging, flip-chip device design, and phosphor coating technology. The high-flux performance of these devices is enabling many new applications for LEDs. Two of the most interesting of these applications are LCD display backlighting and vehicle forward lighting. The advantages of LEDs over competing lighting technologies will be covered in detail. (Abstract Copyright [2002], Wiley Periodicals, Inc.)

  12. Traditional beliefs and electromagnetic fields

    Directory of Open Access Journals (Sweden)

    Colin A. Ross

    2011-09-01

    Full Text Available The author proposes that a wide range of traditional beliefs and practices may provide clues to real electromagnetic field interactions in the biosphere. For instance, evil eye beliefs may be a cultural elaboration of the sense of being stared at, which in turn may have a basis in real electromagnetic emissions through the eye. Data to support this hypothesis are presented. Other traditional beliefs such as remote sensing of game and the importance of connection to the Earth Mother may also contain a kernel of truth. A series of testable scientific hypotheses concerning traditional beliefs and electromagnetic fields is presented. At this stage, the theory does not have sufficient evidence to be accepted as proven; its purpose is to stimulate thought and research

  13. Traditional knowledge and intellectual property.

    Science.gov (United States)

    Brody, Baruch A

    2010-09-01

    Biotechnological inventions are sometimes based upon the traditional knowledge of indigenous communities about the beneficial properties of plants and animals. Some institutions have adopted the uniqueness of traditional knowledge approach, which maintains that the indigenous communities have sui generis rights to a share of the profits from these inventions. Others have adopted the protection of inventive steps approach, which maintains that the inventors are entitled to the full profits from the invention if it involves a non-obvious and novel inventive step. The article analyzes this debate at the Convention on Biological Diversity, at the World Intellectual Property Organization, and at the World Trade Organization. It concludes that the adherents of the uniqueness of traditional knowledge approach have not justified their claims.

  14. Traditional non-Western diets.

    Science.gov (United States)

    Lipski, Elizabeth

    2010-12-01

    In traditional cultures, balancing health with a balanced lifestyle was a core belief. The diseases of modern civilization were rare. Indigenous people have patterns of illness very different from Western civilization; yet, they rapidly develop diseases once exposed to Western foods and lifestyles. Food and medicine were interwoven. All cultures used special or functional foods to prevent disease. Food could be used at different times either as food or medicine. Foods, cultivation, and cooking methods maximized community health and well-being. With methods passed down through generations, cooking processes were utilized that enhanced mineral and nutrient bioavailability. This article focuses on what researchers observed about the food traditions of indigenous people, their disease patterns, the use of specific foods, and the environmental factors that affect people who still eat traditional foods.

  15. TERMITES ENDANGERED TRADITIONAL MEDICAL PLANTS

    Directory of Open Access Journals (Sweden)

    Syaukani Syaukani

    2014-04-01

    Full Text Available Surveys on traditional medical plants affected by termites have been conducted since June to August 2010 at Ketambe, northern Aceh. Traditional medical plants and their natural habitats were obtained through interviewing local people. Termites were collected by adopted a Standardized Sampling Protocol and final. taxonomic confirmation was done with the help of Termite Research Group (the Natural History Museum, London. About 20 species of medical plants were attacked by termites with various levels. Nine genera and 20 species were collected from various habitats throughout Ketambe, Simpur as well as Gunung Setan villages. Coffe (Coffea arabica, hazelnut (Aleurites moluccana , and areca (Area catechu were among the worse of traditional medical  plant that had been attached by the termites.

  16. PENGEMBANGAN LAMPU LED DENGAN TEKNOLOGI PHOTOVOLTAIC (LED-PV SEBAGAI ALAT BANTU PENGUMPUL IKAN PADA PERIKANAN BAGAN

    Directory of Open Access Journals (Sweden)

    Mochamad Arief Sofijanto

    2015-03-01

    mengetahui perbedaan jumlah hasil tangkapan pada bagan tancap akibat perlakuan warna lampu LED yang berbeda. Metode penelitian yang digunakan adalah deskriptif dan experimental fishing dimana rancangan penelitiannya adalah Rancangan Acak Lengkap (RAL dengan perlakuan warna lampu LED sebanyak 5 jenis warna yaitu merah (A, kuning (B, hijau (C, biru (D, dan putih (E dengan 6 kali ulangan. Secara deskriptif hasil penelitian menunjukkan lampu LED dapat digunakan untuk menggantikan lampu petromaks dan lampu LHE. Diperoleh 17 jenis ikan laut yang tertarik pada cahaya lampu LED yang digunakan. Hasil analisis statistik menunjukkan terdapat perbedaan nyata terhadap hasil tangkapan bagan dengan perlakuan warna lampu LED. Berdasarkan Uji Nyata Terkecil dinyatakan bahwa bagan yang menggunakan warna lampu LED biru mendapatkan hasil tangkapan tertinggi kemudian diikuti oleh warna kuning, hijau, putih dan merah.  The set ‘bagan’ (liftnet fishing gear is a kind of fishing gears which using atificial light as fishes gathering. This fishing gear uses an electric generator to turn on the energy saving lamp which hang on under the set ‘bagan’. The price of gasoline more expensive due to the Indonesia government’s fuel subsidy reduced and this make fishing operation costs more expensive for fishermen. This research using the LED lamps that do not use gasoline as fuel because the LED lamps can use the photovoltaic technology (solar cell system. The purposes of this study were: 1 to find out whether the LED lamps can replace the kerosene lamps and saving energy lamps, 2 to know the different in cath using different colours of LED lamps. The reserach methods are descriptive and experimental fishing which used Completely Randomized Design with LED lamps colour treatments i.e: red (A, yellow (B, green (C, blue (D, and white (E, the number of replications are 6 times. LED lamps can be used to replace the kerosene and saving energy lamps. There were 17 species of

  17. The Role of Documentation in Practice-Led Research

    Directory of Open Access Journals (Sweden)

    Nithikul Nimkulrat

    2007-01-01

    Full Text Available Practice-led research in the field of art and design usually involves a study of the interplay between a researcher-practitioner and her artistic work in process. This article seeks to illustrate that documentation of art practice can be a means to record that interplay and it can be used as relevant material in practice-led research. The article will present an account of documentation in practice-led research highlighting two principal aspects: phases of documentation and the role of documentation within the overall research process. The account will capture reflections of the author’s own practice-led research in fiber art, which investigates the relationship between materials and artistic expression, in the context of contemporary art.

  18. Effect of Led Lighting Colors for Laying Japanese Quails

    Directory of Open Access Journals (Sweden)

    KC Nunes

    Full Text Available ABSTRACT Time of exposure and light intensity rearing house may affect the performance and egg quality of laying quails. This research aimed at evaluating the live performance, egg quality, biometry of the reproductive system, and the gastrointestinal tract of Japanese quails (Coturnix coturnix japonica exposed to artificial light-emitting diodes (LED of different colors in comparison with fluorescent lamps. A total of 240 Japanese quails were distributed in completely randomized experimental design with four treatments (fluorescent lamp, and green, red, or blue LED lamps with six replicates of 10 birds each. Average egg weight and eggshell thickness were different (p0.05. The oviduct of 64-d-old hens exposed to green LED lighting was shorter (p<0.05 than those exposed to the fluorescent lamp. Red LED can be used to replace the fluorescent lamps, as they promote the same live performance, egg quality, and morphological development of the reproductive tract of laying Japanese quails.

  19. LED lamp incorporating remote phosphor with heat dissipation features

    Science.gov (United States)

    Tong, Tao; Letoquin, Ronan; Keller, Bernd; Tarsa, Eric

    2016-11-22

    An LED lamp or bulb is disclosed that comprises a light source, a heat sink structure and a remote planar phosphor carrier having at least one conversion material. The phosphor carrier can be remote to the light sources and mounted to the heat sink so that heat from the phosphor carrier spreads into the heat sink. The phosphor carrier can comprise a thermally conductive transparent material and a phosphor layer, with an LED based light source mounted to the heat sink such that light from the light source passes through the phosphor carrier. At least some of the LED light is converted by the phosphor carrier, with some lamp embodiments emitting a white light combination of LED and phosphor light. The phosphor arranged according to the present invention can operate at lower temperature to thereby operate at greater phosphor conversion efficiency and with reduced heat related damage to the phosphor.

  20. Microbial raw data for UV-C LED disinfection study

    Data.gov (United States)

    U.S. Environmental Protection Agency — This study evaluated ultraviolet (UV) light emitting diodes (LEDs) emitting at 260 nm, 280 nm, and the combination of 260|280 nm together for their efficacy at...

  1. 76 FR 66692 - Executive-Led Trade Mission to Afghanistan

    Science.gov (United States)

    2011-10-27

    ... its market economy and increase both domestic and foreign private investment. GIRoA continues to... DEPARTMENT OF COMMERCE International Trade Administration Executive-Led Trade Mission to Afghanistan AGENCY: International Trade Administration, Department of Commerce. ACTION: Notice. Mission...

  2. Laboratory Evaluation of LED T8 Replacement Lamp Products

    Energy Technology Data Exchange (ETDEWEB)

    Richman, Eric E.; Kinzey, Bruce R.; Miller, Naomi J.

    2011-05-23

    A report on a lab setting analysis involving LED lamps intended to directly replace T8 fluorescent lamps (4') showing light output, power, and economic comparisons with other fluorescent options.

  3. LED Retrofit Kits, TLEDs, and Lighting Controls: An Application Guide

    Energy Technology Data Exchange (ETDEWEB)

    None

    2017-03-01

    This document provides guidance for retrofitting existing fluorescent troffers including the LED and associated control options available, the pro/cons and costs/benefits of each option, and agency specific requirements (where applicable).

  4. Integrated parabolic nanolenses on MicroLED color pixels

    Science.gov (United States)

    Demory, Brandon; Chung, Kunook; Katcher, Adam; Sui, Jingyang; Deng, Hui; Ku, Pei-Cheng

    2018-04-01

    A parabolic nanolens array coupled to the emission of a nanopillar micro-light emitting diode (LED) color pixel is shown to reduce the far field divergence. For a blue wavelength LED, the total emission is 95% collimated within a 0.5 numerical aperture zone, a 3.5x improvement over the same LED without a lens structure. This corresponds to a half-width at half-maximum (HWHM) line width reduction of 2.85 times. Using a resist reflow and etchback procedure, the nanolens array dimensions and parabolic shape are formed. Experimental measurement of the far field emission shows a HWHM linewidth reduction by a factor of 2x, reducing the divergence over the original LED.

  5. Light Emitting Diode (LED) circular traffic signal lifetime management system.

    Science.gov (United States)

    2011-02-01

    The objective of this research is to build lifetime curves for red, yellow, and green LED circular traffic signals through 20,000-hr. accelerated stress testing of samples operating under Louisianas environmental conditions.

  6. LED phototherapy improves healing of nipple trauma: a pilot study.

    Science.gov (United States)

    Chaves, Maria Emília de Abreu; Araújo, Angélica Rodrigues; Santos, Suellen Fonsêca; Pinotti, Marcos; Oliveira, Leandro Soares

    2012-03-01

    The purpose of this study was to evaluate the clinical effectiveness of a LED phototherapy prototype apparatus in the healing of nipple trauma in breastfeeding women. There is no scientific evidence of an effective treatment for nipple trauma. The experimental group was treated with orientation on nipple care and adequate breastfeeding techniques in addition to active LED phototherapy. The control group was treated with orientation on nipple care and adequate breastfeeding techniques in addition to placebo LED phototherapy. Participants were treated twice a week, for a total of eight sessions. Healing of the nipple lesions was measured by a reduction in their area, and decrease in pain intensity was measured in accordance with an 11-point Pain Intensity Numerical Rating Scale and a standard 7-point patient global impression of change. Statistically significant reductions in measured nipple lesion area (pLED phototherapy to be an effective tool in accelerating the healing of nipple trauma.

  7. A new LED light source for display cases

    DEFF Research Database (Denmark)

    Dam-Hansen, Carsten; Petersen, Paul Michael

    Abstract: We report a new LED light source suitable for illumination of gold objects. It has a variable correlated color temperature from 2760 K to 2200 K with a high color rendering index up to 97.......Abstract: We report a new LED light source suitable for illumination of gold objects. It has a variable correlated color temperature from 2760 K to 2200 K with a high color rendering index up to 97....

  8. Narratives of making:thinking practice led research in architecture

    OpenAIRE

    Ramsgaard Thomsen, Mette; Tamke, Martin

    2009-01-01

    Practice led research methods investigate their line of inquiries from within a knowledge of doing. The practice is an incorporated skill set, a working method in which the practitioner is trained. The recent focus on practice led research method acknowledges practice as a means of gaining new knowledge. Efforts across the field of practice based research seek to develop means for engaging with issues such as critical assessment, comparability and evaluation. This paper presents research unde...

  9. Biological Research in Canisters (BRIC) - Light Emitting Diode (LED)

    Science.gov (United States)

    Levine, Howard G.; Caron, Allison

    2016-01-01

    The Biological Research in Canisters - LED (BRIC-LED) is a biological research system that is being designed to complement the capabilities of the existing BRIC-Petri Dish Fixation Unit (PDFU) for the Space Life and Physical Sciences (SLPS) Program. A diverse range of organisms can be supported, including plant seedlings, callus cultures, Caenorhabditis elegans, microbes, and others. In the event of a launch scrub, the entire assembly can be replaced with an identical back-up unit containing freshly loaded specimens.

  10. Novel clinical learning from a student-led clinic.

    Science.gov (United States)

    Bostick, Geoff; Hall, Mark; Miciak, Maxi

    2014-12-01

    Student-led clinics have the potential to meet community rehabilitation needs and provide valuable clinical placement experiences. Student-led clinical learning may offer pedagogical advantages similar to problem-based learning; however, this line of research is new and little is known about student-led clinical learning. The purpose of this study was to describe the novel learning experiences of a clinical placement in a student-led clinic from student perspectives. We conducted a descriptive qualitative focus group study with six participants. The focus group began with an open-ended question: 'What does the student-led clinic mean to you as a learner?' This was followed by a discussion of three topics: (1) the student-led clinic is learner focused; (2) faculty involvement in supervision; and (3) learning in a shared space with other students. A content analysis was used to analyse the data, and a summary of the researcher's interpretations was sent to study participants for further comments. There were two major themes that represented experiences within the student-led clinic. 'Increased responsibility' was viewed as a novel experience, and as reducing the perceived gap between the classroom and the 'real world'. As clinical instructors do not carry their own caseload, the second theme pertained to 'Safety-in-learning'. Although this theme was not viewed as novel, it was perceived to be important in enabling autonomy. Increased responsibility' was viewed and as reducing the perceived gap between the classroom and the 'real world Student-led clinics have clear community benefits by mitigating service gaps while providing experiential learning opportunities. These learning opportunities are perceived to be novel, and may resemble advantages observed in the classroom with problem-based learning. © 2014 John Wiley & Sons Ltd.

  11. An Integrated Solid-State LED Luminaire for General Lighting

    Energy Technology Data Exchange (ETDEWEB)

    Kevin Dowling; Fritz Morgan Ihor Lys; Mike Datta; Bernd Keller; Thomas Yuan

    2009-03-31

    A strong systems approach to designing and building practical LED-based replacement lamps is lacking. The general method of taking high-performance LEDs and marrying them to standard printed circuit boards, drivers and a heat sink has fallen short of the promise of LED lighting. In this program, a top-down assessment of requirements and a bottom-up reinvention of LED sources, electronics, optics and mechanics have resulted in the highest performance lamp possible. The team, comprised of Color Kinetics, the leaders in LED lighting and Cree, the leaders in LED devices took an approach to reinvent the package, the driver and the overall form and aesthetic of a replacement source. The challenge was to create a new benchmark in LED lighting - the resultant lamp, a PAR38 equivalent, met the light output, color, color quality and efficacy marks set out in the program as well as being dimmable, which is important for market acceptance. The approach combined the use of multiple source die, a chip-on-board approach, a very efficient driver topology, the use of both direct emission and phosphor conversion, and a unique faceted optic to avoid the losses, artifacts and hotspots of lensed approaches. The integral heat sink provided a mechanical base and airflow using a chimney-effect for use in a wide variety of locations and orientations. These research results led to a much better understanding of the system effects of component level technologies. It was clear that best-of-breed sub-system results do not necessarily result in the best end result for the complete system. In doing this work, we did not neglect the practical aspects of these systems. These were not rarified results and commercially impractical but lent themselves to eventual commercial products in the marketplace. The end result - a high performance replacement lamp - will save significant energy while providing a high-quality light source.

  12. Integrated LED-based luminaire for general lighting

    Science.gov (United States)

    Dowling, Kevin J.; Lys, Ihor A.; Williamson, Ryan C.; Roberge, Brian; Roberts, Ron; Morgan, Frederick; Datta, Michael Jay; Mollnow, Tomas Jonathan

    2016-08-30

    Lighting apparatus and methods employing LED light sources are described. The LED light sources are integrated with other components in the form of a luminaire or other general purpose lighting structure. Some of the lighting structures are formed as Parabolic Aluminum Reflector (PAR) luminaires, allowing them to be inserted into conventional sockets. The lighting structures display beneficial operating characteristics, such as efficient operation, high thermal dissipation, high output, and good color mixing.

  13. Integrated LED-based luminare for general lighting

    Science.gov (United States)

    Dowling, Kevin J.; Lys, Ihor A.; Roberge, Brian; Williamson, Ryan C.; Roberts, Ron; Datta, Michael; Mollnow, Tomas; Morgan, Frederick M.

    2013-03-05

    Lighting apparatus and methods employing LED light sources are described. The LED light sources are integrated with other components in the form of a luminaire or other general purpose lighting structure. Some of the lighting structures are formed as Parabolic Aluminum Reflector (PAR) luminaires, allowing them to be inserted into conventional sockets. The lighting structures display beneficial operating characteristics, such as efficient operation, high thermal dissipation, high output, and good color mixing.

  14. Protection against methanol-induced retinal toxicity by LED photostimulation

    Science.gov (United States)

    Whelan, Harry T.; Wong-Riley, Margaret T. T.; Eells, Janis T.

    2002-06-01

    We have initiated experiments designed to test the hypothesis that 670-nm Light-Emitting Diode (LED) exposure will attenuate formate-induced retinal dysfunction in a rodent model of methanol toxicity. Methanol intoxication produces toxic injury to the retina. The toxic metabolite formed in methanol intoxication is formic acid, a mitochondrial toxin known to inhibit cytochrome oxidase activity. 670-nm LED light has been hypothesized to act by stimulating cytochrome oxidase activity. To test this hypothesis, one group of animals was intoxicated with methanol, a second group was intoxicated with methanol and LED-treated and a third group was untreated. LED treatment (670 nm for 1 min 45 seconds equals 50 mW/cm2, 4 joules/cm2) was administered at 5, 25, and 50 hours after the initial dose of methanol. At 72 hours of methanol intoxication, retinal function was assessed by measurement of ERG responses and retinas were prepared for histologic analysis. ERG responses recorded in methanol-intoxicated animals revealed profound attenuation of both rod-dominated and UV-cone mediated responses. In contrast, methanol- intoxicated animals exposed to LED treatment exhibited a nearly complete recovery of rod-dominated ERG responses and a slight improvement of UV-cone mediated ERG responses. LED treatment also protected the retina against the histopathologic changes produced by formate in methanol intoxication. These data provide evidence that LED phototherapy protects the retina against the cytotoxic actions of formate and are consistent with the hypothesis that LED photostimulation improves mitochondrial respiratory chain function.

  15. LEDs Illuminate Bulbs for Better Sleep, Wake Cycles

    Science.gov (United States)

    2015-01-01

    Life on the International Space Station (ISS) wreaks havoc on an astronaut’s biological rhythms, and one way NASA mitigates the problem is through the use of LED lighting to alternately stimulate energy and focus and induce relaxation. Satellite Beach, Florida-based Lighting Science partnered with Kennedy Space Center to commercialize an LED system designed for the ISS, resulting in its DefinityDigital product line of light bulbs now used in numerous homes, hotel chains, and resorts.

  16. LED lighting combined with solar panels in developing countries

    OpenAIRE

    Amogpai, Ater

    2011-01-01

    The aim of the work was to find out the functionality of LED lighting combined with solar panels in developing countries and to find out the availability of solar energy in different geographical locations. Another aim of the work was to understand the advantages and disadvantages of photovoltaic systems and the optimum combination of PV systems for lighting. Measurements of photovoltaic systems combined with LEDs and fluorescent lighting were conducted in an office building in Finland. ...

  17. Optimal colour quality of LED clusters based on memory colours.

    Science.gov (United States)

    Smet, Kevin; Ryckaert, Wouter R; Pointer, Michael R; Deconinck, Geert; Hanselaer, Peter

    2011-03-28

    The spectral power distributions of tri- and tetrachromatic clusters of Light-Emitting-Diodes, composed of simulated and commercially available LEDs, were optimized with a genetic algorithm to maximize the luminous efficacy of radiation and the colour quality as assessed by the memory colour quality metric developed by the authors. The trade-off of the colour quality as assessed by the memory colour metric and the luminous efficacy of radiation was investigated by calculating the Pareto optimal front using the NSGA-II genetic algorithm. Optimal peak wavelengths and spectral widths of the LEDs were derived, and over half of them were found to be close to Thornton's prime colours. The Pareto optimal fronts of real LED clusters were always found to be smaller than those of the simulated clusters. The effect of binning on designing a real LED cluster was investigated and was found to be quite large. Finally, a real LED cluster of commercially available AlGaInP, InGaN and phosphor white LEDs was optimized to obtain a higher score on memory colour quality scale than its corresponding CIE reference illuminant.

  18. LED Street Lighting Solutions: Flagstaff, Arizona as a Case Study

    Science.gov (United States)

    Hall, Jeffrey C.

    2018-01-01

    Dark-sky protection in Flagstaff, Arizona extends back to 1958, with the first ordinance in the City banning advertising floodlights. The current ordinance, adopted in 1989, is comprehensive and has played a critical role in maintaining the quality of the night sky for astronomy, tourism, public enjoyment, and other purposes. Flagstaff, like many communities around the world, is now working on a transition from legacy bulb-based technology to LED for its outdoor lighting. The City, Lowell Observatory, the U. S. Naval Observatory, and the Flagstaff Dark Skies Coalition have been working intensively for two years to identify an LED-based street lighting solution that will preserve the City's dark skies while meeting municipal needs. We will soon be installing test fixtures for an innovative solution incorporating narrow-band amber LED and modest amounts of low-CCT white LED. In this talk, I will review the types of LEDs available for outdoor lighting and discuss the plans for Flagstaff's street lighting in the LED era, which we hope will be a model for communities worldwide.

  19. Appraisal of traditional technologies i

    African Journals Online (AJOL)

    Jobo

    A survey on the production practices and mode of utilization of mumu – a traditional, ready-to-eat Nigerian cereal-based food product - was conducted to be able to provide information that would be used to improve on the processing, nutritional quality and acceptability of the product. 83 % of respondents indicated the use ...

  20. Waldorf Education: An Innovative Tradition.

    Science.gov (United States)

    Harrington, Sheila

    1993-01-01

    Waldorf Schools represent the largest nonsectarian school movement in the world, shunning fads and technology and relying on the creative gifts of teachers and students. Studies include eurythmy, woodworking, weaving, and traditional academic subjects, and no commercial textbooks are used. Despite teacher/funding shortages, the system continues to…

  1. Comparison of Traditional and const

    African Journals Online (AJOL)

    User

    development were Jean Piaget and John. Dewey (Richardson, 1997). In constructivist approach, learning is an active process in which the learner uses sensory input and constructs meaning out of it. The more traditional formulation of this idea involves the terminology of the active learner (Dewey's term) stressing that.

  2. "Friluftsliv": Traditional Norwegian Outdoor Life.

    Science.gov (United States)

    Tellnes, Atle

    1992-01-01

    Nature and outdoor life are part of Norway's national identity, as exemplified by a long history of nature-inspired art and literature, the formation of outdoor organizations since the turn of the century, and the development of skiing. Norwegian traditional outdoor life is characterized as travelling with respectful use of nature, to achieve a…

  3. Traditional Literacy and Critical Thinking

    Science.gov (United States)

    Dando, Priscille

    2016-01-01

    How school librarians focus on activating critical thinking through traditional literacy development can proactively set the stage for the deep thinking that occurs in all literacy development. The critical-thinking skills students build while becoming accomplished readers and writers provide the foundation for learning in a variety of…

  4. The Zulu traditional birth attendant

    African Journals Online (AJOL)

    birth attendants in their care of pregnant women are .... Postnatal care. The TBA normally visits any woman she has delivered during the traditional lying-in period of 8 days. She bathes the baby, gives him an enema when she considers this necessary, and offers ... instructed to kneel so that her heels press the wound edges ...

  5. Analysis of Traditional Historical Clothing

    DEFF Research Database (Denmark)

    Jensen, Karsten; Schmidt, A. L.; Petersen, A. H.

    2013-01-01

    for establishing a three-dimensional model and the corresponding two-dimensional pattern for items of skin clothing that are not flat. The new method is non-destructive, and also accurate and fast. Furthermore, this paper presents an overview of the more traditional methods of pattern documentation and measurement...

  6. Active Learning versus Traditional Teaching

    Directory of Open Access Journals (Sweden)

    L.A. Azzalis

    2009-05-01

    Full Text Available In traditional teaching most of the class time is spent with the professor lecturing and the students watching and listening. The students work individually, and cooperation is discouraged. On the other hand,  active learning  changes the focus of activity from the teacher to the learners, in which students solve problems, answer questions, formulate questions of their own, discuss, explain, debate during class;  moreover, students work in teams on problems and projects under conditions that assure positive interdependence and individual accountability. Although student-centered methods have repeatedly been shown to be superior to the traditional teacher-centered approach to instruction, the literature regarding the efficacy of various teaching methods is inconclusive. The purpose of this study was to compare the student perceptions of course and instructor effectiveness, course difficulty, and amount learned between the active learning and lecture sections  in Health Sciences´ courses by statistical data from Anhembi Morumbi University. Results indicated significant  difference between active  learning and traditional  teaching. Our conclusions were that strategies promoting  active  learning to  traditional lectures could increase knowledge and understanding.

  7. Traditional Knowledge and Patent Protection

    African Journals Online (AJOL)

    Adam

    Traditional knowledge is also very significant for the economy. The world market for herbal medicines ..... the fair and equitable sharing of the benefits from the use of genetic resources." 97. Since many developing ... and to ensure benefit sharing, rather than to establish a system of positive protection. 98. Article 8(j) of the ...

  8. Comparative Study of Lettuce and Radish Grown Under Red and Blue LEDs and White Fluorescent Lamps

    Science.gov (United States)

    Mickens, Matthew A.; Massa, Gioia; Newsham, Gerard; Wheeler, Raymond; Birmele, Michele

    2016-01-01

    Growing vegetable crops in space will be an essential part of sustaining astronauts during long-range missions. To drive photosynthesis, red and blue light-emitting diodes (LEDs) have attracted attention because of their efficiency, longevity, small size, and safety. In efforts to optimize crop yield, there is also recent interest in analyzing the subtle effects of additional wavelengths on plant growth. For instance, since plants often look purplish gray under red and blue LEDs, the addition of green light allows easy recognition of disease and the assessment of plant health status. However, it is important to know if wavelengths outside the traditional red and blue wavebands have a direct effect on enhancing or hindering the mechanisms involved in plant growth. In this experiment, a comparative study was performed on two short cycle crops of red romaine lettuce (Lactuca sativa cv. "Outredgeous") and radish (Raphanus sativa cv. 'Cherry Bomb'), which were grown under two light treatments. The first treatment being red (630 nm) and blue (450 nm) LEDs alone, while the second treatment consisted of daylight tri-phosphor fluorescent lamps (CCT approximately 5000 K) at equal photosynthetic photon flux (PPF). The treatment effects were evaluated by measuring the fresh biomass produced, plant morphology and leaf dimensions, leaf chlorophyll content, and adenosine triphosphate (ATP) within plant leaf/storage root tissues.

  9. Halogen light versus LED for bracket bonding: shear bond strength

    Directory of Open Access Journals (Sweden)

    Paulo Eduardo Guedes Carvalho

    2013-02-01

    Full Text Available INTRODUCTION: LED light-curing devices seek to provide a cold light activator which allows protocols of material polymerization with shorter duration. OBJECTIVE: The present study aimed to evaluate the shear bond strength of bracket bonding using three types of light-curing devices: One with halogen light (Optilight Plus - Gnatus and two with LEDs (Optilight CL - Gnatus and Elipar Freelight - 3M/ESPE. RESULTS: Comparing the results by analysis of variance, the Gnatus LED device showed an inferior statistical behavior in relation to other light sources, when activated by a short time. But, when it was used for 40 seconds, the polymerization results were consistent with the other evaluated sources. The device with the best average performance was the halogen light, followed by the 3M/ESPE LED. CONCLUSION: It was concluded that the LEDs may be indicated in orthodontic practice, as long as a protocol is used for the application of light with the activation time of 40 seconds.INTRODUÇÃO: os aparelhos de fotopolimerização por LED buscam proporcionar uma luz ativadora fria, que possibilite protocolos de polimerização do material com menor tempo de duração. OBJETIVO: avaliar a resistência à tração da colagem de braquetes, utilizando três tipos de aparelhos fotoativadores: um de luz halógena (Optilight Plus - Gnatus e outros dois de LED (Optilight CL - Gnatus; e Elipar Freelight - 3M/Espe. RESULTADOS: comparando os resultados por meio da análise de variância, o aparelho de LED Gnatus apresentou comportamento estatístico inferior em relação às outras fontes de luz, quando ativado por tempo reduzido. Já quando foi utilizado o tempo de 40 segundos, os resultados de polimerização foram compatíveis com as demais fontes avaliadas. O aparelho que apresentou melhor desempenho médio foi o de luz halógena, seguido pelo LED 3M/Espe. CONCLUSÃO: concluiu-se que os LEDs podem ser indicados na prática ortodôntica, uma vez que seja utilizado

  10. Efficacy of embedded nurse-led versus conventional physician-led follow-up in rheumatoid arthritis

    DEFF Research Database (Denmark)

    de Thurah, Annette; Esbensen, Bente Appel; Roelsgaard, Ida Kristiane

    2017-01-01

    -led follow-up on disease control in patients with RA compared with physician-led follow-up. Primary outcome was disease activity indicated by Disease Activity Score (DAS)-28. Secondary outcomes were: patient satisfaction, physical disability, fatigue, self-efficacy and quality of life. Outcomes were assessed......OBJECTIVE: To compare the efficacy of embedded nurse-led versus conventional physician-led follow-up on disease activity in patients with rheumatoid arthritis (RA). METHODS: In a systematic literature search, we identified randomised controlled trials (RCTs) reporting on the efficacy of nurse...... after 1-year and 2 year follow-ups. RESULTS: Seven studies representing five RCTs, including a total of 723 participants, were included. All but one study included stable patients in low disease activity or remission at baseline. No difference in DAS-28 was found after 1 year (mean difference (MD) -0...

  11. Instructor-led or Learner-led for Elementary Learners to Learn Computer-based Music Composition?

    OpenAIRE

    Ju-Shih Tseng; Ming-Puu Chen

    2010-01-01

    The purpose of the present study was to examine the effects of instructional strategy (instructor-led vs. learner-led) and grade level (third grade vs. fifth grade) on elementary learners’ music composition performance and attitude with the use of a computer-based music composition software. An experimental learning activity was implemented using 5E learning cycle as a pedagogical framework to facilitate learning. A quasi-experimental design was employed with elementary learners participated ...

  12. Verbaalne soolo Jaanus Nõgistolt : Led R-ist, Narva Linna Sümfooniaorkestrist ja Led Zeppelinist / Jaanus Nõgisto ; interv. Margo Pajuste

    Index Scriptorium Estoniae

    Nõgisto, Jaanus, 1956-

    2007-01-01

    Rockansambli Led Zeppelini muusikast, ansamblist Led R ja heliplaadist "Led the R Out" räägib kitarrist Jaanus Nõgisto. Led R ja Narva Linna Sümfooniaorkestri kontserdid: 22. juunil Pärnus ja 14. juulil Haapsalu lossihoovis, ansambli Led R kontsert koos Havana Blackiga 3. aug. Sõru sadamas Hiiumaal

  13. Traditional heritage and trends of modernization

    Directory of Open Access Journals (Sweden)

    Milivojević Snežana M.

    2013-01-01

    Full Text Available The main thesis of contemporary sociological theory and liberal-democratic political doctrine of the 'end of history', 'open society', globalization as a world-historical process is also the thesis about finally liberated the individual and autonomous personality 'of our time'. Modernization theorists from Marx argued that economic development brings changes. Actually, economic development is connected with breakthrough from absolute norms and values towards rationality, tolerance, trust, and participation, so transition from traditionalism to modernism according to theory affects forms of value. This paper examines relationship between values and social (political, economic, cultural transformation as well as the extent to which the validity transformation threatened severe and dramatic social events during last decade. There still remains a dilemma for modern scientific and philosophic thought: is the individual truly free of the pressure of belonging to various types of group compounds like class, ethno-cultural background, family background, gender etc, or have individualization and reflexivity led to an increase in isolation, narcissism, apathy, cynicism, exclusion, marginal position in society, emphasizing materialistic goals and inability to control their own lives.

  14. Revitalization of Cultural and Aesthetical Assets of Iranian Traditional Bazaar

    Directory of Open Access Journals (Sweden)

    Maryam Ziyaee

    2017-12-01

    Full Text Available In recent decades, modernization is extensively changing the face of Iranian cities. Besides, urban places are losing their traditional features, identity and cultural characteristics. Conservation of cultural heritage resources rescued historical parts of the cities; hence, other traditional urban spaces do not receive enough attention and protection due to economic concerns. Mashhad, as one of the main religious touristic destinations in Iran, is unfortunately losing its traditional features due to extensive attractions of physical transformations. Economic profits fascinating constructions into the city center of Mashhad, specially surrounding areas of the holly shrine. This issue has been led to demolishment of the old texture of the city center. Sarshoor bazaar is one of rescued traditional urban public spaces in city center of Mashhad with characteristics of an Iranian ancient bazaar.  This study mainly focuses on cultural and aesthetical patterns of traditional Iranian bazaars in order to provide a conceptual strategy for revitalization of Sarshoor bazaar. To this aim, a theoretical review is provided through main representative factors of cultural landscape to decide about a proper strategy for improving cultural quality of the selected case study. We also provide a practical analysis through social and behavioral patterns of the citizens and pilgrims in public spaces to realize material and immaterial features of Sarshoor bazaar, and consequently, find out any possible opportunity of improving tangible and intangible characteristics of this case study area. To capture cultural landscape qualities of Sarshoor bazaar, a final design is provided to envelope a light traditional surface representing the visual landscape of the bazaar. Main passage and piazzas are also equipped for the movements of pilgrims and setting up annual traditional and social events.

  15. Blue laser diode (LD) and light emitting diode (LED) applications

    International Nuclear Information System (INIS)

    Bergh, Arpad A.

    2004-01-01

    The family of blue LEDs, edge emitting and surface emitting lasers, enable a number of applications. Blue lasers are used in digital applications such as optical storage in high density DVDs. The resolution of the spot size and hence the storage density is diffraction limited and is inversely proportional to the square of the wavelength of the laser. Other applications include printing, optical scanners, and high-resolution photo-lithography. As light emitters, blue LEDs are used for signaling and in direct view large area emissive displays. They are also making inroads into signage and LCD back-lighting, mobile platforms, and decorative accent lighting in curtains, furniture, etc. Blue LEDs produce white light either with phosphor wavelength converters or in combination with red and green LEDs. The full potential of LED light sources will require three devices to enable complete control over color and intensity. Sensing and medical/bio applications have a major impact on home security, on monitoring the environment, and on health care. New emerging diagnostic and therapeutic applications will improve the quality and reduce the cost of health care. (copyright 2004 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  16. Materials and Designs for High-Efficacy LED Light Engines

    Energy Technology Data Exchange (ETDEWEB)

    Ibbetson, James [Cree, Inc., Durham, NC (United States); Gresback, Ryan [Cree, Inc., Durham, NC (United States)

    2017-09-28

    Cree, Inc. conducted a narrow-band downconverter (NBD) materials development and implementation program which will lead to warm-white LED light engines with enhanced efficacy via improved spectral efficiency with respect to the human eye response. New red (600-630nm) NBD materials could result in as much as a 20% improvement in warm-white efficacy at high color quality relative to conventional phosphor-based light sources. Key program innovations included: high quantum yield; narrow peak width; minimized component-level losses due to “cross-talk” and light scattering among red and yellow-green downconverters; and improved reliability to reach parity with conventional phosphors. NBD-enabled downconversion efficiency gains relative to conventional phosphors yielded an end-of-project LED light engine efficacy of >160 lm/W at room temperature and 35 A/cm2, with a correlated color temperature (CCT) of ~3500K and >90 CRI (Color Rending Index). NBD-LED light engines exhibited equivalent luminous flux and color point maintenance at >1,000 hrs. of highly accelerated reliability testing as conventional phosphor LEDs. A demonstration luminaire utilizing an NBD-based LED light engine had a steady-state system efficacy of >150 lm/W at ~3500K and >90 CRI, which exceeded the 2014 DOE R&D Plan luminaire milestone for FY17 of >150 lm/W at just 80 CRI.

  17. LED phototherapy to prevent mucositis: a case report.

    Science.gov (United States)

    Lang-Bicudo, Leticia; Eduardo, Fernanda De Paula; Eduardo, Carlos De Paula; Zezell, Denise Maria

    2008-12-01

    The purpose of this case report was to evaluate the efficacy of phototherapy using light-emitting diodes (LEDs) to prevent oral mucositis in a Hodgkin's disease patient treated with the ABVD (doxorubicin [Adriamycin], bleomycin, vinblastine, and dacarbazine) chemotherapy regimen. Mucositis is a common dose-limiting complication of cancer treatment, and if severe it can lead to alterations in treatment planning or suspension of cancer therapy, with serious consequences for tumor response and survival. Therefore, low-power lasers and more recently LEDs, have been used for oral mucositis prevention and management, with good results. In this study, a 34-year-old man received intraoral irradiation with an infrared LED array (880 nm, 3.6 J/cm2, 74 mW) for five consecutive days, starting on chemotherapy day 1. In each chemotherapy cycle, he received the ABVD protocol on days 1 and 15, and received LED treatment for 5 d during each cycle. To analyze the results, the World Health Organization (WHO) scale was used to grade his mucositis, and a visual analogue scale (VAS) was used for pain evaluation, on days 1, 3, 7, 10, and 13 post-chemotherapy. The results showed that the patient did not develop oral mucositis during the five chemotherapy cycles, and he had no pain symptoms. LED therapy was a safe and effective method for preventing oral mucositis in this case report. However, further randomized studies with more patients are needed to prove the efficacy of this method.

  18. Understanding and controlling chromaticity shift in LED devices

    Energy Technology Data Exchange (ETDEWEB)

    Davis, Lynn; Mills, Karmann; Lamvik, Michael; Perkins, Curtis; Bobashev, Georgiy; Young, Joseph; Yaga, Robert; Johnson, Cortina

    2017-05-30

    Chromaticity shift in light-emitting diode (LED) devices arises from multiple mechanisms, and at least five different chromaticity shift modes (CSMs) have been identified to date. This paper focuses on the impacts of irreversible phosphor degradation as a cause of chromaticity shifts in LED devices. The nitride phosphors used to produce warm white LEDs are especially vulnerable to degradation due to thermal and chemical effects such as reactions with oxygen and water. As a result, LED devices utilizing these phosphors were found to undergo either a green shift or, less commonly, a red shift depending on the phosphor mix in the LED devices. These types of chromaticity shifts are classified as CSM-2 (green shift) and CSM-5 (red shift). This paper provides an overview of the kinetic processes responsible for green and red chromaticity shifts along with examples from accelerated stress testing of 6” downlights. Both CSMs appear to proceed through analogous mechanisms that are initiated at the surface of the phosphor. A green shift is produced by the surface oxidation of the nitride phosphor that changes the emission profile to lower wavelengths. As the surface oxidation reaction proceeds, reactant limitations slow the rate and bulk oxidation processes become more prevalent. We found that a red chromaticity shift arises from quenching of the green phosphor, also possibly due to surface reactions of oxygen, which shift the emission chromaticity in the red direction. In conclusion, we discuss the implications of these findings on projecting chromaticity.

  19. Trust and Traditions in Transitions

    DEFF Research Database (Denmark)

    McQuaid, Sara Dybris

    On New Year’s Eve 2013, months of talks on ‘Dealing with the past’, ‘Flags’ and ‘Parades’ ended without agreement on how to move towards a reconciliation of positions in Northern Ireland. The failure of the talks illustrates the importance of culture and (mis)trust in divided societies, where...... politics often pivot around whose culture shall be official and whose subordinated, whose history shall be remembered and whose forgotten (Jordan and Weedon 1995). These struggles are particularly intense in times of transition where traditions, power relations and frames of relevant remembrance...... are reconfigured. Historically, parading traditions have been important cultural carriers of identity in Northern Ireland. (Jarman 1997). Correspondingly, the marching season has been an arena for politico-cultural struggles and resistance, indexing relations of trust between communities, between society...

  20. Blending traditional and digital marketing

    Directory of Open Access Journals (Sweden)

    Raluca Dania TODOR

    2016-07-01

    Full Text Available It is a matter of fact that we are in the digital era and internet marketing and social media have a significant impact on the way consumers behave, companies do business and it is a must for companies to adapt to the new reality. Due to the fast evolution of the technology, the continuous increase in demand and supply, the supply chain elongation and the big amount of date, the only solution to face the major changes is the automation of all the processes. But even though the new era of communication is here, specialist suggest that companies should not ignore traditional methods, and to try to blend digital marketing with traditional campaigns in order to achieve their goals.

  1. An LED Approach for Measuring the Photocatalytic Breakdown of Crystal Violet Dye

    Science.gov (United States)

    Ryan, Robert E.; Underwood, Lauren W.; ONeal, Duane; Pagnutti, Mary; Davis, Bruce A.

    2009-01-01

    dye degradation on the slides over time, a temperature-stabilized white light LED was used to illuminate the opposite side of the slides. As the dye degraded, the amount of light from the white light LED transmitted through the slide was monitored with a spectrometer and subsequently analyzed to determine and compare the rate of dye degradation for photocatalytically coated versus uncoated slide surfaces. The long-term stability of the spectrometer/white light LED combination, which required only a single reference spectra to be taken for a time series sequence of several hours, enabled accurate measurements of transmitted light over time. Time series transmission curves were generated and results demonstrated that over time the transmission increased much more rapidly on the coated slides than on the control slides. This experimental configuration and methodology for photocatalytic activity measurement minimizes many external variable effects and allows low light level studies to be performed. This study also compares the advantages of this novel LED light source design to traditional mercury lamp systems and non-LED lamp approaches that have conventionally been used. The methodology and experimental design research summarized in this abstract is partly funded by the Department of Homeland Security, Science and Technology Directorate, and by the NASA Stennis Space Center Innovative Partnerships Program.

  2. Insomnia in Iranian Traditional Medicine

    OpenAIRE

    Feyzabadi, Zohre; Jafari, Farhad; Feizabadi, Parvin Sadat; Ashayeri, Hassan; Esfahani, Mohammad Mahdi; Badiee Aval, Shapour

    2014-01-01

    Context: Insomnia is one of the most prevalent sleep disorders characterized by sleep difficulty that impairs daily functioning and reduces quality of life. The burden of medical, psychiatric, interpersonal, and societal consequences of insomnia expresses the importance of diagnosing and treatment of insomnia. The aim of study was to investigate causes of insomnia from the viewpoint of Iranian traditional medicine. Evidence Acquisition: In this review study, we searched insomnia in a few of t...

  3. Health traditions of Sikkim Himalaya.

    Science.gov (United States)

    Panda, Ashok Kumar; Misra, Sangram

    2010-07-01

    Ancient medical systems are still prevalent in Sikkim, popularly nurtured by Buddhist groups using the traditional Tibetan pharmacopoeia overlapping with Ayurvedic medicine. Traditional medical practices and their associated cultural values are based round Sikkim's three major communities, Lepcha, Bhutia and Nepalis. In this study, a semi-structured questionnaire was prepared for folk healers covering age and sex, educational qualification, source of knowledge, types of practices, experience and generation of practice, and transformation of knowledge. These were administered to forty-eight folk healers identified in different parts of Sikkim.490 medicinal plants find their habitats in Sikkim because of its large variations in altitude and climate. For 31 commonly used by these folk healers, we present botanical name, family, local name, distribution, and parts used, together with their therapeutic uses, mostly Rheumatoid arthritis, Gout, Gonorrhea, Fever, Viral flu, asthma, Cough and Cold, indigestion, Jaundice etc. A case treated by a folk healer is also recounted. This study indicates that, in the studied area, Sikkim's health traditions and folk practices are declining due to shifts in socio-economic patterns, and unwillingness of the younger generation to adopt folk healing as a profession.

  4. Health traditions of Sikkim Himalaya

    Directory of Open Access Journals (Sweden)

    Ashok Kumar Panda

    2010-01-01

    Full Text Available Ancient medical systems are still prevalent in Sikkim, popularly nurtured by Buddhist groups using the traditional Tibetan pharmacopoeia overlapping with Ayurvedic medicine. Traditional medical practices and their associated cultural values are based round Sikkim′s three major communities, Lepcha, Bhutia and Nepalis. In this study, a semi-structured questionnaire was prepared for folk healers covering age and sex, educational qualification, source of knowledge, types of practices, experience and generation of practice, and transformation of knowledge. These were administered to forty-eight folk healers identified in different parts of Sikkim. 490 medicinal plants find their habitats in Sikkim because of its large variations in altitude and climate. For 31 commonly used by these folk healers, we present botanical name, family, local name, distribution, and parts used, together with their therapeutic uses, mostly Rheumatoid arthritis, Gout, Gonorrhea, Fever, Viral flu, asthma, Cough and Cold, indigestion, Jaundice etc. A case treated by a folk healer is also recounted. This study indicates that, in the studied area, Sikkim′s health traditions and folk practices are declining due to shifts in socio-economic patterns, and unwillingness of the younger generation to adopt folk healing as a profession.

  5. Combined daylight and intelligent LED lighting - getting the daylight into the buildings; Kombineret dagslys og intelligent LED belysning - fae dagslys ind i bygningerne. Slutrapport

    Energy Technology Data Exchange (ETDEWEB)

    Dam-Hansen, C.; Corell, D.D.; Thorseth, A.; Behrensdorff Poulsen, P. [Technical Univ. of Denmark, DTU Fotonik, DTU Risoe Campus, Roskilde (Denmark); Markvart, J.; Iversen, A.; Logadottir, A. [Aalborg Univ., Statens Byggeforskningsinstitut (SBi), Koebenhavn (Denmark)

    2013-03-15

    The main result of the project is the construction of the new intelligent and dynamic LED lighting system for demonstration and research purposes, and a number of extensive user testing is completed. The LED lighting system is a total system for office lighting with ceiling fixtures and desk lamps, which has made it possible to create a general and workplace lighting in two offices each with two work places. The system is installed in a day light laboratory for such two office spaces. All lamps can be controlled via a developed computer interface, and the desk lamps are further manually controllable by a user via two buttons for color temperature and brightness, respectively. The new intelligent and dynamic lighting system is based on color mixing LED technology and makes it possible to control the color composition, color coordinates and thus the color temperature of the light. Control-wise, the system is pre-programmed to produce white light with a correlated color temperature from 2700 K to 7000 K. The color composition is optimized from the desire for a very good color given at a general CRI value of 92-97 over the area. The system can be dimmed 20-100 %, with no significant change in the light's color properties. A mini-spectrometer is calibrated and built-in in the system and provides the current estimate of daylight brightness and color temperature through measurement of daylight color scheme in the visible range. The system uses daylight properties to control the light from the LED lighting system. The results of user tests show, that the developed possibility to automatically control of light in the office depending on the daylight color temperature is considered to be equally preferred and results in equally satisfied users as a traditional lighting system with even lighting in the room. On the other hand, user results showed that there were both energy savings and more satisfied users to be gained by providing users the opportunity to self-adjust either

  6. [Photoelectric parametric test system of LED based on virtual instrument].

    Science.gov (United States)

    Yang, Song-Tao; Wang, Jing; Wang, Li-Dong; Liang, Pei; Dong, Qian-Min

    2014-11-01

    The standardized measuring principle, requirements and implementations of the above parameters of LEDs were researched and analyzed in the present paper. Then a comprehensive test system involved with optics, machinery and computer was designed to accomplish data acquisition, algorithm design and interface design on virtual instrument using NI data acquisition card USB6210. And convincing results of LEDs' parameters, including peak wavelength, width of half-peak wavelength, centroid wavelength, chromaticity coordinates, purity, correlated color temperature and the forward voltage/current, were achieved with good consistency based on the measured spectrum. The system owns simple interface, reliable algorithms and stable results. Respective measurements on five kinds of color of LED result in an average error less than 3%, which show an ideal performance of the system.

  7. Values-led Participatory Design - Mediating the Emergence of Values

    DEFF Research Database (Denmark)

    Iversen, Ole Sejer; Leong, Tuck Wah

    2012-01-01

    There is a growing interest in values-led inquiries within participatory design. One approach argues that working with values is a recursive 3-phase process that supports the emergence, development and grounding of values. In this paper we focus solely upon the emergence phase, proposing...... an approach that can support the emergence of values during the initial phase of a values-led inquiry. To illustrate this approach and to ground our discussion, we draw from a recent participatory design case where we were engaged in the design of digital technology to support the experiences of young adults...... with severe intellectual disabilities, in an art museum. By describing how we establish, negotiate and the debrief values during this initial phase of a values-led inquiry. By foregrounding both explicit and implicit mediation in the PD process we show how a theoretical understanding of mediation can...

  8. LED-based digital hologram reconstruction by compressive sensing

    Science.gov (United States)

    Weng, Jiawen; Yang, Chuping; Qin, Yi; Li, Hai

    2015-10-01

    LED-based digital hologram, considered as low-coherence digital hologram, is confined to in-line holography because the interference fringes could be observed only when the angle between the object and reference wave is small enough. So, phase-shifting technique is usually employed. But it is not fit for dynamic analysis for demanding more than one hologram. A numerical reconstruction method based on compressive sensing theory for single LED-based digital hologram is proposed to achieve dynamic analysis. By this method, the out-of-focus twin image and the coherent noise can be inhibited to some extent. The theory is presented in detail, and experimental result on LED-based digital holography with USAF pattern as test target, is performed to demonstrate the feasibility and validity of the method.

  9. LED Phototherapy with Gelatin Sponge Promotes Wound Healing in Mice.

    Science.gov (United States)

    Zhang, Heng; Liu, Shupeng; Yang, Xiangfei; Chen, Na; Pang, Fufei; Chen, Zhenyi; Wang, Tingyun; Zhou, Jianshe; Ren, Fuji; Xu, Xiaoyin; Li, Taihao

    2018-01-01

    Tiny but highly efficient, a light-emitting diode (LED) can power a therapy device, such as a phototherapy device, and, at the same time, decrease the device's size requirements. In this study, a LED phototherapy device was designed to investigate the possible impact on wound healing using a mouse model and a cell line exposed to red and blue light. To enhance wound phototherapy, a gelatin sponge was fabricated. Results showed that the red and blue lights promoted cell growth and wound healing, while the blue light with a gelatin sponge protected the wound from infection in the early stages of wound healing. The LED phototherapy device combined with the gelatin sponge, therefore, has potential significance in clinical application for wound healing. © 2017 The American Society of Photobiology.

  10. Developing a nurse-led clinic using transformational leadership.

    Science.gov (United States)

    Gousy, Mamood; Green, Kim

    2015-03-25

    Nurses are at the forefront of implementing and managing change, given constantly changing healthcare services and the increase in demand for health care. Therefore, it is important to identify the best style of leadership to engage nurses in implementing service-led improvements. This article explores the effects of transformational leadership in bringing about service-led improvements in health care, using the example of setting up a nurse-led acupuncture clinic to optimise the care of patients with chronic pain. Transformational leadership was used throughout the project - from the initial local planning, training and development, through to liaising with the appropriate staff and deciding on an evaluation strategy. Transformational leadership proved to be an effective way to engage and empower nurses and other members of the chronic pain team to enable them to achieve the project aims.

  11. InGaN/GaN Nanowire LEDs and Lasers

    KAUST Repository

    Zhao, Chao

    2016-01-01

    The large specific surface, and the associated high density of surface states was found to limit the light output power and quantum efficiency of nanowire-array devices, despite their potential for addressing the “green-gap” and efficiency-droop issues. The phonon and carrier confinement in nanowires also led to junction heating, and reduced heat dissipation. In this paper, we will present our studies on effective surface states passivation in InGaN/GaN quantum-disks (Qdisks)-in-nanowire light-emitting diodes (LEDs) and lasers grown on silicon (Si), as well as our recent work on nanowires LEDs grown on bulk-metal, a non-conventional substrate.

  12. LED radiation: possible photobiological risks and safety regulations. Pt. 2

    International Nuclear Information System (INIS)

    Horak, W.

    2008-01-01

    With all due euphoria regarding the new illumination possibilities, one can quite often observe a certain degree of uncertainty concerning eye hazard issues in conjunction with intense LED radiation. Moreover, the related general requirements for product- as well as for workplace-safety are rather new. Thus, the possible hazards by the optical radiation of LEDs will be analyzed in this two-port contribution. Part 1 aims to provide a review of these hazards as well as of the bases for their evaluation. The impact of these requirements on state-of-the-art LEDs will be examined in part 2. Compared with conventional light sources, it turns out that there are hardly any differences in this respect. (orig.)

  13. Reported challenges in nurse-led randomised controlled trials

    DEFF Research Database (Denmark)

    Wang Vedelø, Tina; Lomborg, Kirsten

    2011-01-01

    , nursing research, nursing, research, challenges, barriers, nurse's role, nurse attitude, attitude of health personnel. Findings: The literature on reported challenges and barriers between 1999 and 2009 showed that the most often experienced problems were (i) sufficient patient recruitment, (ii...... between nurse researchers and clinicians, including education, training and support may increase the success rate and quality of nurse-led studies using the randomised controlled trial.......Aims: The purpose of this integrative literature review was to explore and discuss the methodological challenges nurse researchers report after conducting nurse-led randomised controlled trials in clinical hospital settings. Our research questions were (i) what are the most commonly experienced...

  14. Determination of organic compounds in water using ultraviolet LED

    Science.gov (United States)

    Kim, Chihoon; Ji, Taeksoo; Eom, Joo Beom

    2018-04-01

    This paper describes a method of detecting organic compounds in water using an ultraviolet LED (280 nm) spectroscopy system and a photodetector. The LED spectroscopy system showed a high correlation between the concentration of the prepared potassium hydrogen phthalate and that calculated by multiple linear regression, indicating an adjusted coefficient of determination ranging from 0.953-0.993. In addition, a comparison between the performance of the spectroscopy system and the total organic carbon analyzer indicated that the difference in concentration was small. Based on the close correlation between the spectroscopy and photodetector absorbance values, organic measurement with a photodetector could be configured for monitoring.

  15. Remotely Triggered Solar Blind Signaling Using Deep Ultraviolet (UV) LEDs

    Science.gov (United States)

    2011-06-01

    resistance is held constant, the voltage drop across the resistor is also proportional to the amount of light detected. This voltage was measured...distance from the LED to the photodiode was not held constant. To avoid the output voltage limit on the opamp , the intensity of the four HS LEDs was...period for driving voltages up to 8.0 volts. As before, a GaP photodiode was used in conjunction with an opamp , but the output voltage was read with an

  16. Problematic fine bore nasogastric intubation: A radiographer led service development

    International Nuclear Information System (INIS)

    Law, Robert

    2008-01-01

    Developing from the intubation and performing of small bowel enteroclysis a consultant radiographer led service expanded to include problematic gastric, enteric and colonic intubations for diagnostic, therapeutic and interventional purposes. The radiographer led service has also extended to include 'hot reporting' chest images taken to check siting of ward placed nasogastric tubes as well as resiting those tubes that were misplaced. The service has demonstrated itself to be safe and efficient. It has also proven to be both cost and clinically effective. The protracted discomfort and distress to the patient are reduced by minimizing the delay in correctly relocating misplaced tubes

  17. Pharmacist-led medication review in an acute admissions unit

    DEFF Research Database (Denmark)

    Hansen, Trine Graabæk; Bonnerup, Dorthe Krogsgaard; Kjeldsen, Lene Juel

    2015-01-01

    of principles and methodologies, and the practical procedure is seldom described in detail, which makes reproducing study findings difficult. The objective of this paper is to provide a detailed description of a procedure developed and used for pharmacist-led medication review in acute admissions units......) collection of information about the patient's medical treatment, (3) patient interview, (4) critical examination of the patient's medications and (5) recommendations for the hospital physician.Conclusions We have provided a detailed description of a procedure for pharmacist-led medication review. We do so...

  18. New insights into consumer-led food product development

    DEFF Research Database (Denmark)

    Costa, Ana I. A.; Jongen, W.M.F.

    2006-01-01

    industry are described. Contrary to previous optimistic views, it is put forward that without significant changes taking place in the mindset of the organizations involved in Europe's food R&D, the way forward for consumer-led innovation strategies in the agri-business sector will be long and hard.......This paper builds upon a review of relevant marketing, consumer science and innovation management literature to introduce the concept of consumer-led new product development and describe its main implementation stages. The potential shortcomings of this concept's application in European food...

  19. High-Voltage LED Light Engine with Integrated Driver

    Energy Technology Data Exchange (ETDEWEB)

    Soer, Wouter [Lumileds LLC, San Jose, CA (United States)

    2016-02-29

    LED luminaires have seen dramatic changes in cost breakdown over the past few years. The LED component cost, which until recently was the dominant portion of luminaire cost, has fallen to a level of the same order as the other luminaire components, such as the driver, housing, optics etc. With the current state of the technology, further luminaire performance improvement and cost reduction is realized most effectively by optimization of the whole system, rather than a single component. This project focuses on improving the integration between LEDs and drivers. Lumileds has developed a light engine platform based on low-cost high-power LEDs and driver topologies optimized for integration with these LEDs on a single substrate. The integration of driver and LEDs enables an estimated luminaire cost reduction of about 25% for targeted applications, mostly due to significant reductions in driver and housing cost. The high-power LEDs are based on Lumileds’ patterned sapphire substrate flip-chip (PSS-FC) technology, affording reduced die fabrication and packaging cost compared to existing technology. Two general versions of PSS-FC die were developed in order to create the desired voltage and flux increments for driver integration: (i) small single-junction die (0.5 mm2), optimal for distributed lighting applications, and (ii) larger multi-junction die (2 mm2 and 4 mm2) for high-power directional applications. Two driver topologies were developed: a tapped linear driver topology and a single-stage switch-mode topology, taking advantage of the flexible voltage configurations of the new PSS-FC die and the simplification opportunities enabled by integration of LEDs and driver on the same board. A prototype light engine was developed for an outdoor “core module” application based on the multi-junction PSS-FC die and the single-stage switch-mode driver. The light engine meets the project efficacy target of 128 lm/W at a luminous flux

  20. Flicker Reduction in LED-LCDs with Local Backlight

    DEFF Research Database (Denmark)

    Nadernejad, Ehsan; Mantel, Claire; Burini, Nino

    2013-01-01

    Local backlight dimming of LCD with LED backlight can reduce power consumption and improve quality of displayed images and videos. However, important variations of LED over time produce a visually annoying artifact called flickering. In this work, we propose a new algorithm to reduce flickering...... while maintaining video quality. The proposed algorithm uses an adaptive second order Infinite Impulse Response (IIR) in which coefficients are calculated from the local image features. Experimental results show that the proposed method can reduce flickering while simultaneously keeping similar video...

  1. Two phase interleaved buck converter for driving high power LEDs

    DEFF Research Database (Denmark)

    Beczkowski, Szymon; Munk-Nielsen, Stig

    2011-01-01

    The goal of this paper is to evaluate an interleaved buck topology for driving high current light-emitting diodes. Low output capacitor value allows the use of non-electrolytic capacitors extending the lifetime of the converter. Converter is operated as a constant, regulated current source which...... increases luminous efficacy of LED compared to PWM dimmed system. Because of the low dynamic resistance of LEDs the duty cycle of the converter does not change greatly with controlled current. By setting the input voltage of the buck converter to around twice the voltage of diode strings, converter can...

  2. Monte carlo analysis of multicolour LED light engine

    DEFF Research Database (Denmark)

    Chakrabarti, Maumita; Thorseth, Anders; Jepsen, Jørgen

    2015-01-01

    A new Monte Carlo simulation as a tool for analysing colour feedback systems is presented here to analyse the colour uncertainties and achievable stability in a multicolour dynamic LED system. The Monte Carlo analysis presented here is based on an experimental investigation of a multicolour LED...... light engine designed for white tuneable studio lighting. The measured sensitivities to the various factors influencing the colour uncertainty for similar system are incorporated. The method aims to provide uncertainties in the achievable chromaticity coordinates as output over the tuneable range, e...

  3. LED phototherapy system in skin treatment and detecting

    Science.gov (United States)

    Chen, Hsi-Chao; Wu, Jih-Huah; Lin, Ching-Huang; Ma, Shih-Hsin

    2010-08-01

    In this research, a new module of skin treatment has been proposed. The 40 pieces of red and 36 pieces of yellow LEDs are utilized to be the light sources in treatment the cracks and corrosions on skin, and the 4 pieces of white light LEDs are applied in lighting on skin. In addition, the image of skin could be obtained by a CCD webcam, and the skin inspection will be determined by number of pores in images. Finally, the good experimental results have been obtained in human body.

  4. High quality Danish design with intelligent LED light. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Petersen, Paul Michael; Dam-Hansen, C.; Thestrup, B.; Pedersen, Henrik (Technical Univ. of Denmark, DTU Fotonik, Roskilde (Denmark)); Olsen, Jesper (JesperOlsen ApS, Frederiksberg (Denmark)); Falleboe, H.; Andersen, Jakob (MORFOSO, Copenhagen (Denmark))

    2010-02-15

    Based on the results achieved in a previous project, which enabled a number of designers to be trained in the potential of LED lighting technology, this project developed intelligent LED fixtures for work purposes and for private homes. The two types of fixtures both meet the original project objective of good colour rendition with Ra indices above 90 and colour temperatures variable within the interval 3,300 to 4,400 K. Furthermore, with luminous efficacies of 60 lumen/W, both fixtures have energy efficiencies exceeding that of an average energy-friendly light source. (ln)

  5. Life-Cycle Assessment of Energy and Environmental Impacts of LED Lighting Products, Part 3: LED Environmental Testing

    Energy Technology Data Exchange (ETDEWEB)

    Tuenge, Jason R.; Hollomon, Brad; Dillon, Heather E.; Snowden-Swan, Lesley J.

    2013-03-01

    This report covers the third part of a larger U.S. Department of Energy (DOE) project to assess the life-cycle environmental and resource impacts in the manufacturing, transport, use, and disposal of light-emitting diode (LED) lighting products in relation to incumbent lighting technologies. All three reports are available on the DOE website (www.ssl.energy.gov/tech_reports.html). • Part 1: Review of the Life-Cycle Energy Consumption of Incandescent, Compact Fluorescent and LED Lamps; • Part 2: LED Manufacturing and Performance; • Part 3: LED Environmental Testing. Parts 1 and 2 were published in February and June 2012, respectively. The Part 1 report included a summary of the life-cycle assessment (LCA) process and methodology, provided a literature review of more than 25 existing LCA studies of various lamp types, and performed a meta-analysis comparing LED lamps with incandescent and compact fluorescent lamps (CFLs). Drawing from the Part 1 findings, Part 2 performed a more detailed assessment of the LED manufacturing process and used these findings to provide a comparative LCA taking into consideration a wider range of environmental impacts. Both reports concluded that the life-cycle environmental impact of a given lamp is dominated by the energy used during lamp operation—the upstream generation of electricity drives the total environmental footprint of the product. However, a more detailed understanding of end-of-life disposal considerations for LED products has become increasingly important as their installation base has grown. The Part 3 study (reported herein) was undertaken to augment the LCA findings with chemical analysis of a variety of LED, CFL, and incandescent lamps using standard testing procedures. A total of 22 samples, representing 11 different models, were tested to determine whether any of 17 elements were present at levels exceeding California or Federal regulatory thresholds for hazardous waste. Key findings include: • The selected

  6. Instructor-led or Learner-led for Elementary Learners to Learn Computer-based Music Composition?

    Directory of Open Access Journals (Sweden)

    Ju-Shih Tseng

    2010-03-01

    Full Text Available The purpose of the present study was to examine the effects of instructional strategy (instructor-led vs. learner-led and grade level (third grade vs. fifth grade on elementary learners’ music composition performance and attitude with the use of a computer-based music composition software. An experimental learning activity was implemented using 5E learning cycle as a pedagogical framework to facilitate learning. A quasi-experimental design was employed with elementary learners participated in the experiment. The results revealed that (a fifth grader outperformed third graders in creativity, whereas third graders were extrinsically motivated and perceived that the computer-based music composition software was useful in learning music composition more than fifth graders were and did; and (b learners with instructor-led instructional strategy outperformed learners with learned-led instructional strategy in creativity and craftsmanship and held high extrinsic motivation than learners with learner-led. The implementations and suggestions for future study were discussed in the present study.

  7. Traditional justice in the reconciliation between Rwanda and Burundi

    Directory of Open Access Journals (Sweden)

    Antoni Castel

    2009-10-01

    Full Text Available This article reviews the use of traditional justice in two post-conflicts in the Great Lakes region: those of Rwanda and Burundi. In Rwanda, the government, led by the Rwanda Patriotic Front (FPR, has modernised and shaped for its own interests the gacaca, who are responsible for seeking justice for the victims of the 1994 genocide. In Burundi, the government has yet not deployed all the transitional justice mechanisms as envisaged in the Arusha agreement. The bushingantahe (the rehabilitation of whom is also envisaged in the agreement have not yet been incorporated into transitional justice.

  8. Traditional musical instruments in Serbian folk tradition: Etnophraseological perspective

    Directory of Open Access Journals (Sweden)

    Đorđević Vesna N.

    2016-01-01

    Full Text Available The aim of this work is to give an insight in the significance and role of native musical instruments in Serbian folk tradition based on the representation of these instruments in the Serbian ethnographic material. The focus will also be on the semantic description of phraseological units that have those instruments as central components, in order to show how different cultural contents, typical for a particular native culture, are precisely reflected in the phraseology and language fund of that culture. We will first try to present those instruments and provide brief ethnological analysis of their role in the folk life, followed by the whole repertoire and semantic description of phrasemes, whose central lexical element has the name of a folk musical instrument or some related actions. Ethnographic and phraseological data related to folk instruments was taken from the Serbian ethnographic material and dictionaries of Serbian language. The analysis showed that in Serbian traditional culture musical instruments were used as a signaling tools as well as for communication between people and higher powers.

  9. Warfarin anticoagulation in hemodialysis patients with atrial fibrillation: comparison of nephrologist-led and anticoagulation clinic-led management.

    Science.gov (United States)

    Bahbahani, Hamad; AlTurki, Ahmed; Dawas, Ahmed; Lipman, Mark L

    2018-01-08

    There is conflicting evidence of benefit versus harm for warfarin anticoagulation in hemodialysis patients with atrial fibrillation. This equipoise may be explained by suboptimal Time in Therapeutic Range (TTR), which correlates well with thromboembolic and bleeding complications. This study aimed to compare nephrologist-led management of warfarin therapy versus that led by specialized anticoagulation clinic. In a retrospective cohort of chronic hemodialysis patients from two institutions (Institution A: Nephrologist-led warfarin management, Institution B: Anticoagulation clinic-led warfarin management), we identified patients with atrial fibrillation who were receiving warfarin for thromboembolic prophylaxis. Mean TTRs, proportion of patients achieving TTR ≥ 60%, and frequency of INR testing were compared using a logistic regression model. In Institution A, 16.7% of hemodialysis patients had atrial fibrillation, of whom 36.8% were on warfarin. In Institution B, 18% of hemodialysis patients had atrial fibrillation, and 55.5% were on warfarin. The mean TTR was 61.8% (SD 14.5) in Institution A, and 60.5% (SD 15.8) in Institution B (p-value 0.95). However, the proportion of patients achieving TTR ≥ 60% was 65% versus 43.3% (Adjusted OR 2.22, CI 0.65-7.63) and mean frequency of INR testing was every 6 days versus every 13.9 days in Institutions A and B respectively. There was no statistical difference in mean TTR between nephrologist-led management of warfarin and that of clinic-led management. However, the former achieved a trend toward a higher proportion of patients with optimal TTR. This improved therapeutic results was associated with more frequent INR monitoring.

  10. LED Light to improve Strawberry Flavour, Quality and Production

    NARCIS (Netherlands)

    Hanenberg, M.A.A.; Janse, J.; Verkerke, W.

    2016-01-01

    A current demonstration in the greenhouses of Wageningen UR in Bleiswijk (the Netherlands) shows positive results of LED light on the quality and production of strawberries (Fragaria x ananassa). In this demonstration two strawberry cultivars, Elsanta and Sonata, are exposed to three different light

  11. Current-voltage model of LED light sources

    DEFF Research Database (Denmark)

    Beczkowski, Szymon; Munk-Nielsen, Stig

    2012-01-01

    Amplitude modulation is rarely used for dimming light-emitting diodes in polychromatic luminaires due to big color shifts caused by varying magnitude of LED driving current and nonlinear relationship between intensity of a diode and driving current. Current-voltage empirical model of light...

  12. A color management system for multi-colored LED lighting

    DEFF Research Database (Denmark)

    Chakrabarti, Maumita; Thorseth, Anders; Jepsen, Jørgen

    2015-01-01

    A new color control system is described and implemented for a five–color LED light engine, covering a wide white gamut. The system combines a new way of using pre-calibrated look-up tables and a rule-based optimization of chromaticity distance from the Planckian locus with a calibrated color sensor...

  13. Effectiveness of a Volunteer-Led Crafts Group Intervention amongst ...

    African Journals Online (AJOL)

    The purpose of this study was to determine the effectiveness of a volunteer led crafts group intervention (VLCG) as an adjunct to antidepressant medication on mild to moderately depressed women. A quasi-experimental, non-equivalent, control group study was conducted in an urban, psychiatric clinic. Depression was ...

  14. Patient safety in midwifery-led care in the Netherlands

    NARCIS (Netherlands)

    Martijn, L.L.M.; Jacobs, A.J.E.; Maassen, I.I.M.; Buitendijk, S.S.E.; Wensing, M.M.

    2013-01-01

    Objective: to describe the incidence and characteristics of patient safety incidents in midwifery-led care for low-risk pregnant women. Design: multi-method study. Setting: 20 midwifery practices in the Netherlands; 1,000 patient records. Population: low-risk pregnant women. Methods: prospective

  15. Nurse-led rehabilitation after gynaecological cancer surgery

    DEFF Research Database (Denmark)

    Seibæk, Lene

    2009-01-01

      Abstract This article presents the preliminary results and experiences from an ongoing study aiming to: Develop and test a nurse-led multidisciplinary rehabilitation programme for women who undergo surgery for localised gynaecological cancers.Evaluate the effect of the programme prospectively o...

  16. Refugee-led humanitarianism in Lebanon’s Shatila camp

    Directory of Open Access Journals (Sweden)

    Hind Sharif

    2018-02-01

    Full Text Available Refugee-led humanitarian initiatives by ‘established’ Palestinian refugees in response to the arrival of ‘new’ displaced Syrians to Shatila camp raise key questions about the limitations of the humanitarian system and representations of refugees as passive victims.

  17. Compact collimators for high brightness blue LEDs using dielectric multilayers

    NARCIS (Netherlands)

    Cornelissen, H.J.; Ma, H.; Ho, C.; Li, M.; Mu, C.

    2011-01-01

    A novel method is presented to inject the light of millimeter-sized high-brightness blue LEDs into light guides of submillimeter thickness. Use is made of an interference filter that is designed to pass only those modes that will propagate in the light guide by total internal reflection. Other modes

  18. High power deep UV-LEDs for analytical optical instrumentation

    Czech Academy of Sciences Publication Activity Database

    Li, Y.; Dvořák, Miloš; Nesterenko, P. N.; Nuchtavorn, N.; Macka, M.

    2018-01-01

    Roč. 255, č. 2 (2018), s. 1238-1243 ISSN 0925-4005 Institutional support: RVO:68081715 Keywords : deep UV Light emitting diodes (LEDs) * optical detection * portable analytical instrumentation Subject RIV: CB - Analytical Chemistry, Separation OBOR OECD: Analytical chemistry Impact factor: 5.401, year: 2016

  19. Effect of Laser and LED on Enzymatic Production of Ceramide

    DEFF Research Database (Denmark)

    Hongyu, Zhang; Zhang, Long; Tidemand-Lichtenberg, Peter

    2011-01-01

    using HPTLC (high performance thin-layer chromatography) at 0.5, 1, 2, 3, 4, 6, 17, 24 h after irradiation. The duration of effect was evaluated from the experimental data. The results show that enzyme activity can be increased by using both laser and LED sources whose wavelength is located within...

  20. LED en energiezuinigheid en kwaliteit bij Red Naomi!

    NARCIS (Netherlands)

    Gelder, de Arie; Burg, van der Rick

    2017-01-01

    In order to achieve a signifi cant energy saving, WUR Greenhouse Horticulture and Delphy conducted research under a lighting system with Deep Red / Blue Top- LED. Objectives were consistent growth by uniform light level, improvement of fl ower size and stem weight and 25% saving on electricity. In

  1. Advanced LED package with temperature sensors and microfluidic cooling

    NARCIS (Netherlands)

    Ye, H.; Zeijl, H. van; Sokolovskij, R.; Gielen, A.W.J.; Zhang, G.Q.

    2013-01-01

    Light-emitting diodes (LEDs) are revolutionizing the illumination with energy savings and enhanced functionality. However, around 80% of the input power will be still transferred to heat. As the elevated temperature negatively affects the maximum light output, efficiency, quality, reliability and

  2. Heterostructures for Increased Quantum Efficiency in Nitride LEDs

    Energy Technology Data Exchange (ETDEWEB)

    Davis, Robert F. [Carnegie Mellon Univ., Pittsburgh, PA (United States)

    2010-09-30

    Task 1. Development of an advanced LED simulator useful for the design of efficient nitride-based devices. Simulator will contain graphical interface software that can be used to specify the device structure, the material parameters, the operating conditions and the desired output results. Task 2. Theoretical and experimental investigations regarding the influence on the microstructure, defect concentration, mechanical stress and strain and IQE of controlled changes in the chemistry and process route of deposition of the buffer layer underlying the active region of nitride-based blue- and greenemitting LEDs. Task 3. Theoretical and experimental investigations regarding the influence on the physical properties including polarization and IQE of controlled changes in the geometry, chemistry, defect density, and microstructure of components in the active region of nitride-based blue- and green-emitting LEDs. Task 4. Theoretical and experimental investigations regarding the influence on IQE of novel heterostructure designs to funnel carriers into the active region for enhanced recombination efficiency and elimination of diffusion beyond this region. Task 5. Theoretical and experimental investigations regarding the influence of enhanced p-type doping on the chemical, electrical, and microstructural characteristics of the acceptor-doped layers, the hole injection levels at Ohmic contacts, the specific contact resistivity and the IQE of nitride-based blue- and green-emitting LEDs. Development and optical and electrical characterization of reflective Ohmic contacts to n- and p-type GaN films.

  3. High power deep UV-LEDs for analytical optical instrumentation

    Czech Academy of Sciences Publication Activity Database

    Li, Y.; Dvořák, Miloš; Nesterenko, P. N.; Nuchtavorn, N.; Macka, M.

    Roč. 255, č. 2 ( 2018 ), s. 1238-1243 ISSN 0925-4005 Institutional support: RVO:68081715 Keywords : deep UV Light emitting diodes (LEDs) * optical detection * portable analytical instrumentation Subject RIV: CB - Analytical Chemistry, Separation OBOR OECD: Analytical chemistry Impact factor: 5.401, year: 2016

  4. Luminaries-level structure improvement of LEDs for heat dissipation ...

    Indian Academy of Sciences (India)

    Due to its significant advantages such as high efficiency, long lifetime, low power consump- tion, inconceivable controllability and high ... However, till now LED chip can only convert 20% of the input power into light while the rest 80% is converted ... the middle of computational domain. Turbulence natural convection and ...

  5. Underwater Wireless Optical Communication System Using Blue LEDs

    Science.gov (United States)

    Lin, Aobo; Tong, Zheng; Song, Yuhang; Kong, Meiwei; Xu, Jing

    2016-02-01

    We demonstrate a self-designed underwater wireless optical communication system using blue LEDs. The performance of the transmitter and receiver was experimentally investigated. Four different square wave signals (10 KHz, 100 KHz, 500 KHz and 1 MHz) were successfully transmitted via a short water channel at the first phase.

  6. LED light requirements ... for greenhouses and growth rooms

    NARCIS (Netherlands)

    Nederhoff, E.M.

    2011-01-01

    LEDs have potential for use as grow lights in greenhouses to supplement low natural light levels, and also for use in growth rooms and 'plant factories' as the main light source. The light spectrum is critical. Unfortunately, it seems that there is not a simple recipe freely available for growing

  7. Luminaries-level structure improvement of LEDs for heat dissipation ...

    Indian Academy of Sciences (India)

    Furthermore, the natural convection heat transfer process of LED luminaries is simulated by computational fluid dynamics (CFD) model before and after the structural modification. As shown by computational results, boring through-hole is beneficial to develop bottomto-top natural convection, eliminate local circumfluence, ...

  8. EC-LEDS Mexico: Advancing Clean Energy Goals

    Energy Technology Data Exchange (ETDEWEB)

    2016-07-01

    EC-LEDS works with the government of Mexico to help meet its goals of reducing greenhouse gas emissions from the energy sector. The program targets specific, highly technical areas where Mexico has indicated the program can add value and make an impact.

  9. Optical and thermal simulation chain for LED package

    NARCIS (Netherlands)

    Tapaninen, O.; Myohanen, P.; Majanen, M.; Sitomaniemi, A.; Olkkonen, J.; Hildenbrand, V.; Gielen, A.W.J.; Mackenzie, F.V.; Barink, M.; Smilauer, V.; Patzak, B.

    2016-01-01

    This paper presents a test case for coupling two physical aspects of an LED, optical and thermal, using specific simulation models coupled through an open source platform for distributed multi-physics modelling. The glue code for coupling is written with Python programming language including

  10. CALiPER Application Summary Report 15. LED Floodlights

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2012-05-01

    This report analyzes the independently tested performance of 10 LED floodlights purchased between August and December 2011. The group included a wide range of products, both physically and in performance characteristics, which mirrors the nearly indefinite range of conventional luminaires designated as floodlights.

  11. Kattuvad hääled / Reet Varblane

    Index Scriptorium Estoniae

    Varblane, Reet, 1952-

    2008-01-01

    Iisraeli ja palestiina kunstnike näitus "Kattuvad hääled/Overlapping Voices" Essli muuseumis Klosterneuburgis Austrias 16. V-25. X. Kuraatorid: Tal Adler (Iisrael, juut), Amal Murkus (Iisrael, palestiinlane), Karin Schneider ja Friedemann Derschmidt (Austria). Karlheinz ja Agnes Esslile kuuluvast eramuuseumist (1991, arhitekt Heinz Tesar)

  12. Performance of LED fluorescence microscopy for the detection of ...

    African Journals Online (AJOL)

    Introduction: Ziehl-Neelsen (ZN) bright-field microscopy is time-consuming, with poor sensitivity, even under optimal conditions. Introduction of Primo Star iLED fluorescent microscopy (FM) may improve TB case finding at referral hospitals in Rwanda. The study aimed to determine the acceptability and effectiveness of iLED ...

  13. New insights into consumer-led food product development

    NARCIS (Netherlands)

    Costa, A.I.A.; Jongen, W.M.F.

    2006-01-01

    This paper builds upon a review of relevant marketing, consumer science and innovation management literature to introduce the concept of consumer-led new product development and describe its main implementation stages. The potential shortcomings of this concept's application in European food

  14. Biologically inspired LED lens from cuticular nanostructures of firefly lantern

    Science.gov (United States)

    Kim, Jae-Jun; Lee, Youngseop; Kim, Ha Gon; Choi, Ki-Ju; Kweon, Hee-Seok; Park, Seongchong; Jeong, Ki-Hun

    2012-01-01

    Cuticular nanostructures found in insects effectively manage light for light polarization, structural color, or optical index matching within an ultrathin natural scale. These nanostructures are mainly dedicated to manage incoming light and recently inspired many imaging and display applications. A bioluminescent organ, such as a firefly lantern, helps to out-couple light from the body in a highly efficient fashion for delivering strong optical signals in sexual communication. However, the cuticular nanostructures, except the light-producing reactions, have not been well investigated for physical principles and engineering biomimetics. Here we report a unique observation of high-transmission nanostructures on a firefly lantern and its biological inspiration for highly efficient LED illumination. Both numerical and experimental results clearly reveal high transmission through the nanostructures inspired from the lantern cuticle. The nanostructures on an LED lens surface were fabricated by using a large-area nanotemplating and reconfigurable nanomolding with heat-induced shear thinning. The biologically inspired LED lens, distinct from a smooth surface lens, substantially increases light transmission over visible ranges, comparable to conventional antireflection coating. This biological inspiration can offer new opportunities for increasing the light extraction efficiency of high-power LED packages. PMID:23112185

  15. Fluorescent silicon carbide materials for white LEDs and photovoltaics

    DEFF Research Database (Denmark)

    Syväjärvi, Mikael; Ou, Haiyan; Wellmann, Peter

    the luminescence appears in the infrared region in a broad range from 700 to 1100 nm. This potentially can be used to develop an infrared LED for de-icing in wind power and airplanes, or medical applications. Further on, a very efficient solar cell material can be investigated by studying the impurity effect...

  16. Farmer led multiplication of rosette resistant groundnut varieties

    African Journals Online (AJOL)

    Mo

    sure way to provide poor farmers with access to improved varieties, practices, knowledge and information required for ... sustainable, and appropriate, especially for resource poor farmers. In view of this situation this project promotes farmer- led multiplication of rosette resistant Groundnuts varieties .... appropriate solutions.

  17. Bright infrared LEDs based on colloidal quantum-dots

    KAUST Repository

    Sun, Liangfeng

    2013-01-01

    Record-brightness infrared LEDs based on colloidal quantum-dots have been achieved through control of the spacing between adjacent quantum-dots. By tuning the size of quantum-dots, the emission wavelengths can be tuned between 900nm and 1650nm. © 2013 Materials Research Society.

  18. Liquid cooling applications on automotive exterior LED lighting

    Science.gov (United States)

    Aktaş, Mehmet; Şenyüz, Tunç; Şenyıldız, Teoman; Kılıç, Muhsin

    2018-02-01

    In this study cooling of a LED unit with heatsink and liquid cooling block which is used in automotive head lamp applications has been investigated numerically and experimentally. Junction temperature of a LED which is cooled with heatsink and liquid cooling block obtained in the experiment. 23°C is used both in the simulation and the experiment phase. Liquid cooling block material is choosed aluminium (Al) and polyamide. All tests and simulation are performed with three different flow rate. Temperature distribution of the designed product is investigated by doing the numerical simulations with a commercially software. In the simulations, fluid flow is assumed to be steady, incompressible and laminar and 3 dimensional (3D) Navier-Stokes equations are used. According to the calculations it is obtained that junction temperature is higher in the heatsink design compared to block cooled one. By changing the block material, it is desired to investigate the variation on the LED junction temperature. It is found that more efficient cooling can be obtained in block cooling by using less volume and weight. With block cooling lifetime of LED can be increased and flux loss can be decreased with the result of decreased junction temperature.

  19. Assessment of community led total sanitation uptake in rural Kenya

    African Journals Online (AJOL)

    Objective: to assess the magnitude of Community Led total sanitation (CLts) triggering to certification of Open Defecation free (ODF) villages in rural Kenya. Design: A retrospective descriptive study. Setting: the 47 .... Eldoret, Kenya and the Ethics Review Board of. Médecins sans Frontières, Geneva, Switzerland, on.

  20. Multiple Primary LED Lamp Colour Controller with Inherent Brightness Limitation

    NARCIS (Netherlands)

    Barcena, R.; Ackermann, B.

    2007-01-01

    There is a strong interest in using LEDs for general illumination due to the potential they offer for energy saving, environmental friendliness, new opportunities in lighting design, and control of the intensity, colour, and spatial distribution of light. General illumination requires primarily