WorldWideScience

Sample records for aloud boosts connectivity

  1. Thinking outside the box when reading aloud: Between (localist) module connection strength as a source of word frequency effects.

    Science.gov (United States)

    Besner, Derek; Risko, Evan F

    2016-10-01

    The frequency with which words appear in print is a powerful predictor of the time to read monosyllabic words aloud, and consequently all models of reading aloud provide an explanation for this effect. The entire class of localist accounts assumes that the effect of word frequency arises because the mental lexicon is organized around frequency of occurrence (the action is inside the lexical boxes). We propose instead that the frequency of occurrence effect is better understood in terms of the hypothesis that the strength of between module connections varies as a function of word frequency. Findings from 3 different lines of investigation (experimental and computational) are difficult to understand in terms of the "within lexicon" account, but are consistent with the strength of between-module connections account. (PsycINFO Database Record PMID:27657439

  2. Grid Connected Solar PV System with SEPIC Converter Compared with Parallel Boost Converter Based MPPT

    Directory of Open Access Journals (Sweden)

    T. Ajith Bosco Raj

    2014-01-01

    Full Text Available The main objective of this work is to study the behaviour of the solar PV systems and model the efficient Grid-connected solar power system. The DC-DC MPPT circuit using chaotic pulse width modulation has been designed to track maximum power from solar PV module. The conversion efficiency of the proposed MPPT system is increased when CPWM is used as a control scheme. This paper also proposes a simplified multilevel (seven level inverter for a grid-connected photovoltaic system. The primary goal of these systems is to increase the energy injected to the grid by keeping track of the maximum power point of the panel, by reducing the switching frequency, and by providing high reliability. The maximum power has been tracked experimentally. It is compared with parallel boost converter. Also this model is based on mathematical equations and is described through an equivalent circuit including a PV source with MPPT, a diode, a series resistor, a shunt resistor, and dual boost converter with active snubber circuit. This model can extract PV power and boost by using dual boost converter with active snubber. By using this method the overall system efficiency is improved thereby reducing the switching losses and cost.

  3. The Series Connected Buck Boost Regulator Concept for High Efficiency Light Weight DC Voltage Regulation

    Science.gov (United States)

    Birchenough, Arthur G.

    2003-01-01

    Improvements in the efficiency and size of DC-DC converters have resulted from advances in components, primarily semiconductors, and improved topologies. One topology, which has shown very high potential in limited applications, is the Series Connected Boost Unit (SCBU), wherein a small DC-DC converter output is connected in series with the input bus to provide an output voltage equal to or greater than the input voltage. Since the DC-DC converter switches only a fraction of the power throughput, the overall system efficiency is very high. But this technique is limited to applications where the output is always greater than the input. The Series Connected Buck Boost Regulator (SCBBR) concept extends partial power processing technique used in the SCBU to operation when the desired output voltage is higher or lower than the input voltage, and the implementation described can even operate as a conventional buck converter to operate at very low output to input voltage ratios. This paper describes the operation and performance of an SCBBR configured as a bus voltage regulator providing 50 percent voltage regulation range, bus switching, and overload limiting, operating above 98 percent efficiency. The technique does not provide input-output isolation.

  4. A Read-Aloud for Science (Read It Aloud).

    Science.gov (United States)

    Richardson, Judy S.; Breen, Margaret

    1996-01-01

    Recommends a young adult read-aloud selection for science classes on endangered species. Describes listening, writing, discussing, investigating, and debating activities capitalizing on this read-aloud. (SR)

  5. Thinking Aloud Influences Perceived Time

    DEFF Research Database (Denmark)

    Hertzum, Morten; Holmegaard, Kristin Due

    2015-01-01

    a person is already attending, there is evidence that thinking aloud does not influence thought and behavior. Method: In an experiment, 16 thinking-aloud participants and 16 control participants solved a code-breaking task 24 times each. Participants estimated task duration. The 24 trials involved two......Objective: We investigate whether thinking aloud influences perceived time. Background: Thinking aloud is widely used in usability evaluation, yet it is debated whether thinking aloud influences thought and behavior. If thinking aloud is restricted to the verbalization of information to which...... levels of time constraint (timed, untimed) and resulted in two levels of success (solved, unsolved). Results: The ratio of perceived time to clock time was lower for thinking-aloud than control participants. Participants overestimated time by an average of 47% (thinking aloud) and 94% (control...

  6. Comparison of Current Control Strategies Applied to a Boost-Rectifier Connected to a Direct Drive Wave Energy Converter

    OpenAIRE

    Rocha Mendonca, Hugo; Martínez González, Sergio; Ramírez Prieto, Dionisio

    2015-01-01

    Direct drive wave energy converters are characterized by a direct conversion of the wave energy into electricity with no intermediate mechanical conversion system. For this reason, optimization methods for maximizing the absorbed power have to be designed for acting on the electrical generator. Besides, this type of system requires power electronics to be connected to the grid. This paper evaluates three different current control strategies applied to a boost-rectifier in the ac-dc stage as p...

  7. Not Just for After Lunch: Accelerating Vocabulary Growth during Read-Aloud

    Science.gov (United States)

    Toth, Aimee

    2013-01-01

    This Teaching Tip is based on a vocabulary study conducted at Thetford Elementary in Thetford, Vermont. It explores the positive effects of utilizing paired conversational response and teaching of associative connections within read aloud. Teachers who scaffold student understanding during read aloud using the Four C's: compare and contrast…

  8. Bifurcation and chaos in multi-parallel-connected current-mode controlled boost DC-DC converters

    Institute of Scientific and Technical Information of China (English)

    CHEN Ming-liang; MA Wei-ming

    2006-01-01

    This paper studied the bifurcation and chaos phenomenon in a multi-parallel-connected current-mode controlled boost DC-DC converter system with the use of nonlinear mapping bifurcation theory of two dimensions,and the changing rules of the bifurcation charts with the increase of the control parallels and control parameters were concluded.The method of discrete mapping modeling was utilized to construct the difference equations of the system operating in continuous conduction mode (CCM).Analyses and computer emulations were made.

  9. Boosting foundations and algorithms

    CERN Document Server

    Schapire, Robert E

    2012-01-01

    Boosting is an approach to machine learning based on the idea of creating a highly accurate predictor by combining many weak and inaccurate "rules of thumb." A remarkably rich theory has evolved around boosting, with connections to a range of topics, including statistics, game theory, convex optimization, and information geometry. Boosting algorithms have also enjoyed practical success in such fields as biology, vision, and speech processing. At various times in its history, boosting has been perceived as mysterious, controversial, even paradoxical.

  10. Is Reading Tests Aloud an Accommodation for Youth with or at Risk for ADHD?

    Science.gov (United States)

    Spiel, Craig Freeman; Mixon, Clifton S.; Holdaway, Alex S.; Evans, Steven W.; Harrison, Judith R.; Zoromski, Allison K.; Yost, Joanna Sadler

    2016-01-01

    In this study, we intend to determine if reading tests aloud provides a differential boost to youth with elevated symptoms of Attention-Deficit/Hyperactivity Disorder (ADHD) relative to same-aged peers. Participants were 36 youth, 44% with or at risk for ADHD, who participated in a week long summer camp. Over the course of the week, youth attended…

  11. Taking the Time to Read Aloud

    Science.gov (United States)

    Braun, Patricia

    2010-01-01

    Reading aloud is a widely accepted and successful practice in elementary school classrooms, but is rarely found in middle school classrooms (Allen 2000). However, results from initial research on reading aloud in secondary classrooms support the practice (Ivey and Fisher 2006). The benefits of reading aloud are many, but two benefits are…

  12. Improving the Quality of Think-Alouds

    Science.gov (United States)

    Ness, Molly; Kenny, MaryBeth

    2016-01-01

    An essential element in teaching children to effectively comprehend text is the use of teacher-led think alouds. This article presents a three-step model to improve the quality and quantity of think alouds in K-6 classrooms. The article follows elementary teachers who planned, implemented, transcribed, and reflected upon think aloud lessons to…

  13. Stability analysis of a high-step-Up DC grid-connected two-stage boost DC-DC converter

    Directory of Open Access Journals (Sweden)

    El Aroudi A.

    2014-01-01

    Full Text Available High conversion ratio switching converters are used whenever there is a need to step-up dc source voltage level to a much higher output dc voltage level such as in photovoltaic systems, telecommunications and in some medical applications. A simple solution for achieving this high conversion ratio is by cascading different stages of dc-dc boost converters. The individual converters in such a cascaded system are usually designed separately applying classical design criteria. However these criteria may not be applicable for the complete cascaded system . This paper first presents a glimpse on the bifurcation behavior that a cascade connection of two boost converters can exhibit. It is shown that the desired periodic orbit can undergo period doubling leading to subharmonic oscillations and chaotic regimes. Then, in order to simplify the analysis the second stage is considered as constant current sink and design-oriented analysis is carried out to obtain stability boundaries in the parameter space by taking into account slope interactions between the state variables in the two-different stages.

  14. Analysis, simulation and experimental study of chaotic behaviour in parallel-connected DC-DC boost converters

    Energy Technology Data Exchange (ETDEWEB)

    Natsheh, Ammar N.; Kettleborough, J. Gordon [Department of Electronic and Electrical Engineering, Loughborough University, Loughborough, Leicestershire LE11 3TU (United Kingdom); Nazzal, Jamal M. [Faculty of Engineering, Al-Ahliyya Amman University, Post Code 19328 Amman (Jordan)], E-mail: jnazzal@ammanu.edu.jo

    2009-03-15

    The paper describes an experimental study of the bifurcation behaviour of a modular peak current-mode controlled DC-DC boost converter. The parallel-input/parallel-output converter comprises two identical boost circuits and operates in the continuous-current conduction mode. A comparison is made between the results obtained from an experimental converter with those obtained from bifurcation diagrams generated from previous work and waveforms from a new MATLAB/SIMULINK simulation presented in this paper. Another comparison is made between the modular converter diagrams with those of the single boost converter.

  15. Triangulation of the neurocomputational architecture underpinning reading aloud.

    Science.gov (United States)

    Hoffman, Paul; Lambon Ralph, Matthew A; Woollams, Anna M

    2015-07-14

    The goal of cognitive neuroscience is to integrate cognitive models with knowledge about underlying neural machinery. This significant challenge was explored in relation to word reading, where sophisticated computational-cognitive models exist but have made limited contact with neural data. Using distortion-corrected functional MRI and dynamic causal modeling, we investigated the interactions between brain regions dedicated to orthographic, semantic, and phonological processing while participants read words aloud. We found that the lateral anterior temporal lobe exhibited increased activation when participants read words with irregular spellings. This area is implicated in semantic processing but has not previously been considered part of the reading network. We also found meaningful individual differences in the activation of this region: Activity was predicted by an independent measure of the degree to which participants use semantic knowledge to read. These characteristics are predicted by the connectionist Triangle Model of reading and indicate a key role for semantic knowledge in reading aloud. Premotor regions associated with phonological processing displayed the reverse characteristics. Changes in the functional connectivity of the reading network during irregular word reading also were consistent with semantic recruitment. These data support the view that reading aloud is underpinned by the joint operation of two neural pathways. They reveal that (i) the ATL is an important element of the ventral semantic pathway and (ii) the division of labor between the two routes varies according to both the properties of the words being read and individual differences in the degree to which participants rely on each route.

  16. DC-DC boost-flyback converter functioning as input stage for one phase low power grid-connected inverter

    Directory of Open Access Journals (Sweden)

    Kawa Adam

    2014-09-01

    Full Text Available The paper treats about main problems of one phase DC-AC microinverters that allow single solar cell to be joined with the grid. One of the issues is to achieve high voltage gain with high efficiency in DC circuit, which is necessary for proper operation of inverter. The operating principles, results of practical implementation and investigations on boost-flyback converter, which meets mentioned demands, are presented. (high step-up DC-DC boost-flyback converter for single phase grid microinverter

  17. READING ALOUD STRATEGIES IN READING ENGLISH TEXTS

    OpenAIRE

    Iyen Nurlaelawati; Shofa Dzulqodah

    2014-01-01

    Abstract: Reading aloud by a young language learner shows unique patterns as the evidence of his/her language data processing. This study, thus, explored the strategies applied by an Indonesian young language learner to read English written texts aloud to identify errors that actually bring certain benefits in her language learning process such as making intelligent guesses when she encountered unfamiliar words. It adopted qualitative case study design involving a seven-year old girl as the s...

  18. Multiple low frequency dual reference PWM control of a grid connected photovoltaic three phase NPC inverter with DC/DC boost converter

    Directory of Open Access Journals (Sweden)

    Mechouma Rabiaa

    2014-01-01

    Full Text Available In recent years, power demand of industrial applications has increased significantly reaching some megawatts. The use of multilevel converters for applications of medium and high powers is proposed as a solution to drawback semiconductor technology. A multilevel converter not only achieves high power ratings, but also enables the use of renewable energy sources. Renewable energy sources such as photovoltaic can be easily interfaced to a multilevel converter system for a high power application. This paper presents the simulation study in Matlab/Simulink of a grid connected photovoltaic three phase Neutral Point Clamped (NPC inverter with DC/DC boost converter for constant and variable solar radiation.

  19. A Read-Aloud for Foreign Languages: Becoming a Language Master (Read It Aloud).

    Science.gov (United States)

    Richardson, Judy S.

    1998-01-01

    Describes the use of some read-alouds from Alexandre Dumas'"The Count of Monte Cristo" which helped to demonstrate some principles of learning foreign languages. Describes briefly the read aloud selection, discusses some specific activities that relate to foreign language learning, and discusses specific language arts activities. (SR)

  20. Revisiting Read-Aloud: Instructional Strategies that Encourage Students' Engagement with Texts

    Science.gov (United States)

    Morrison, Vanessa; Wlodarczyk, Lisa

    2009-01-01

    This article discusses the importance of comprehension strategy instruction in the early grades. It explains how one teacher integrated Alphaboxes, making connections, and the discussion web as part of her read aloud instructional practice. The article argues that, through careful planning, higher order thinking strategies can be modified for…

  1. The AdaBoost Flow

    CERN Document Server

    Lykov, A; Vaninsky, K

    2011-01-01

    We introduce a dynamical system which we call the AdaBoost flow. The flow is defined by a system of ODEs with control. We show how by a suitable choice of control AdaBoost algorithm of Schapire and Freund and arc-gv algorithm of Breiman can be embedded in the AdaBoost flow. We also show how previously studied by Schapire and Singer confidence rated prediction can be obtained from our continuous time approach. We introduce a new continuous time algorithm which we call superBoost and describe its properties. The AdaBoost flow equations coincide with the equations of dynamics of the nonperiodic Toda system written in terms of spectral variables. This establishes a connection between two seemingly unrelated fields of boosting algorithms and classical integrable models. Finally we explain similarity of the AdaBoost flow with Perelman's ideas to control Ricci flow.

  2. Stories to Be Read Aloud (Booksearch).

    Science.gov (United States)

    English Journal, 1989

    1989-01-01

    Presents junior and senior high school teachers' suggestions for short stories to read aloud in a single class period, including "The Laughing Man" (J. D. Salinger), "A & P" (John Updike), "Epicac" (Kurt Vonnegut), "The Story of an Hour" (Kate Chopin), and "The Yellow Wallpaper" (Charlotte Perkins Gilman). (MM)

  3. The disruptive effect of Think Aloud

    DEFF Research Database (Denmark)

    Nielsen, Janni; Yssing, Carsten

    2004-01-01

    Think Aloud (TA), we ask the question: what happens when users are required to verbalise their visual perceptions and interactions? We argue that TA may have a disruptive effect, suggesting that other techniques be considered. With a theoretical distinction between focal and subsidiary awareness...

  4. Thinking aloud in the presence of interruptions and time constraints

    DEFF Research Database (Denmark)

    Hertzum, Morten; Holmegaard, Kristin Due

    2013-01-01

    and time constraints, two frequent elements of real-world activities. We find that the presence of auditory, visual, audiovisual, or no interruptions interacts with thinking aloud for task solution rate, task completion time, and participants’ fixation rate. Thinking-aloud participants also spend longer...... responding to interruptions than control participants. Conversely, the absence or presence of time constraints does not interact with thinking aloud, suggesting that time pressure is less likely to make thinking aloud reactive than previously assumed. Our results inform practitioners faced with the decision...

  5. How the nature of science is presented to elementary students in science read-alouds

    Science.gov (United States)

    Rivera, Seema

    Students as early as elementary school age are capable of learning the aspects of the nature of science (NOS), and the National Benchmarks incorporate the NOS as part of the learning objectives for K--2 students. Learning more about elementary science instruction can aid in understanding how the NOS can be taught or potentially integrated into current teaching methods. Although many teaching methods exist, this study will focus on read-alouds because they are recommended for and are very common in elementary schools. The read-aloud practice is particularly helpful to young students because most of these students have a higher listening comprehension than reading comprehension. One of the main components of the read-aloud practice is the discourse that takes place about the trade book. Both explicit and implicit messages are communicated to students by teachers' language and discussion that takes place in the classroom. Therefore, six multisite naturalistic case studies were conducted to understand elementary teachers' understanding of the NOS, students' understandings of the NOS, trade book representations of the NOS, and read-aloud practices and understandings in upstate New York. The findings of the study revealed that teachers and students held mostly naive and mixed understandings of the NOS. The trade books that had explicit connections to the NOS helped teachers discuss NOS related issues, even when the teachers did not hold strong NOS views. Teachers who held more informed NOS views were able to ask students NOS related questions. All teachers showed they need guidance on how to translate their NOS views into discussion and see the significance of the NOS in their classroom. Explicit NOS instruction can improve student understanding of the NOS, however the focus should be not only on teachers and their NOS understanding but also on the books used. These results show that quality trade books with explicit connections to the NOS are a useful instructional tool

  6. Learning from K-5 Teachers Who Think Aloud

    Science.gov (United States)

    Ness, Molly

    2016-01-01

    An essential element in teaching children to effectively comprehend text is the use of teacher-led think-alouds. The overarching objective of this study was to explore how to better prepare early career teachers to conduct think-alouds in their classrooms. Data from 31 teachers consisted of (1) questionnaires, (2) lesson plans, (3) lesson…

  7. Science Language Accommodation in Elementary School Read-Alouds

    Science.gov (United States)

    Glass, Rory; Oliveira, Alandeom W.

    2014-01-01

    This study examines the pedagogical functions of accommodation (i.e. provision of simplified science speech) in science read-aloud sessions facilitated by five elementary teachers. We conceive of read-alouds as communicative events wherein teachers, faced with the task of orally delivering a science text of relatively high linguistic complexity,…

  8. The Power of Planning Developing Effective Read-Alouds

    Science.gov (United States)

    Shedd, Meagan K.; Duke, Nell K.

    2008-01-01

    In the midst of many circle times, one can overhear small voices adding to the words from the book being read aloud by the teacher. Sometimes the children's words relate to the text, sometimes not. Early childhood educators recognize the importance of reading aloud every day to develop children's language and early literacy skills. Recommendations…

  9. Application of bifurcation theory to current-mode controlled parallel-connected DC-DC boost converters with multi bifurcation parameters

    Energy Technology Data Exchange (ETDEWEB)

    Natsheh, Ammar N. [Faculty of Engineering, Al-Ahliyya Amman University, Post Code 19328 Amman (Jordan); Nazzal, Jamal M. [Faculty of Engineering, Al-Ahliyya Amman University, Post Code 19328 Amman (Jordan)]. E-mail: jnazzal@ammanu.edu.jo

    2007-08-15

    This work describes the bifurcational behavior of a modular peak current-mode controlled DC-DC boost converter with multi bifurcation parameters. The parallel-input/parallel-output converter consists of two identical boost circuits and operates in the continuous-current conduction mode (CCM). A nonlinear mapping in closed form is derived and bifurcation diagrams are generated using MATLAB. A comparison is made between the modular converter diagrams with those of the single boost converter. The effect of introducing mutual coupling between the inductors of the constituent modules is also addressed. Results are verified using the circuit analysis package PSPICE.

  10. COMBINING COOPERATIVE LEARNING WITH READING ALOUD BY TEACHERS

    Directory of Open Access Journals (Sweden)

    George Jacobs

    2004-06-01

    Full Text Available This article begins with a section that describes cooperative learning and explains eight cooperative learning principles. The second section discusses the interface between cooperative learning and language pedagogy. Next is a section about the why and how of reading aloud by teachers. The heart of the article resides in the last and longest section which describes techniques for integrating cooperative learning with reading aloud by teachers. These techniques include ones that can be used before, while and after the teacher has read aloud to the class.

  11. COMBINING COOPERATIVE LEARNING WITH READING ALOUD BY TEACHERS

    OpenAIRE

    George Jacobs; Dan Hannah

    2004-01-01

    This article begins with a section that describes cooperative learning and explains eight cooperative learning principles. The second section discusses the interface between cooperative learning and language pedagogy. Next is a section about the why and how of reading aloud by teachers. The heart of the article resides in the last and longest section which describes techniques for integrating cooperative learning with reading aloud by teachers. These techniques include ones that can be used b...

  12. SUBPAL: A Device for Reading Aloud Subtitles from Television and Cinema

    DEFF Research Database (Denmark)

    Nielsen, Simon; Bothe, Hans-Heinrich

    2007-01-01

    The primary focus of this paper is accessibility barriers for visually impaired people and people with dyslexia. Due to their disability a segment of these people have limited accessibility to the subtitle content presented on television and in the cinema. It is utterly important to be able...... to this problem is SubPal, a text to speech device which can be connected to the television or to a video camera. The subtitle content in the presented video stream is read aloud through a multilingual speech synthesizer. Hence the solution is applicable for television and in the cinema, in several countries...

  13. Environmental agency in read-alouds

    Science.gov (United States)

    Oliveira, Alandeom W.; Rogers, Patterson; Quigley, Cassie F.; Samburskiy, Denis; Barss, Kimberly; Rivera, Seema

    2015-06-01

    Despite growing interest in helping students become agents of environmental change who can, through informed decision-making and action-taking, transform environmentally detrimental forms of human activity, science educators have reduced agency to rationality by overlooking sociocultural influences such as norms and values. We tackle this issue by examining how elementary teachers and students negotiate and attribute responsibility, credit, or blame for environmental events during three environmental read-alouds. Our verbal analysis and visual representation of meta-agentive discourse revealed varied patterns of agential attribution. First, humans were simultaneously attributed negative agentive roles (agents of endangerment and imbalance) and positive agentive roles (agents of prevention, mitigation, and balance). Second, while wolves at Yellowstone were constructed as intentional (human-like) agents when they crossed over into the human world to kill livestock in nearby farms, polar bears in the Arctic were denied any form of agential responsibility when they approached people's homes. Third, anthropogenic causation of global warming was constructed as distal and indirect chains of cause and effect (i.e., sophisticated sequences of ripple effects), whereas its mitigation and prevention assumed the form of simple and unidirectional causative links (direct and proximal causality). Fourth, the notion of balance of nature was repeatedly used as a justification for environmental conservation but its cause and dynamic nature remained unclear. And, fifth, while one teacher promoted environmental agency by encouraging students to experience positive emotions such as love of nature, freedom, and oneness with nature, the other teachers encouraged students to experience negative emotions such as self-blame and guilt. This study's main significance is that it highlights the need for environmental educators who set out to promote environmental agency to expand the focus of

  14. The Effect of Reading Aloud on English Speaking Ability

    Institute of Scientific and Technical Information of China (English)

    朱子奇

    2014-01-01

    English speaking ability is one of the most direct ways and standards to judge whether one ’s English is good or not. How to improve English speaking ability is always a heated topic among English learners. Many educators have examined that reading English aloud has been attested to be an effective method of learning English, especially improving English speaking abili-ty. This paper, through a questionnaire survey, is to analyze the relationship between students ’oral English outcome and their reading aloud, followed by the reasons why reading aloud affects English speaking ability, attempting to find out effective strate-gies to help English learners to improve their English speaking ability.

  15. Leading the Way to Appropriate Selection, Implementation, and Evaluation of the Read-Aloud Accommodation

    Science.gov (United States)

    Thurlow, Martha L.; Lazarus, Sheryl S.; Hodgson, Jennifer R.

    2012-01-01

    The read-aloud accommodation is one of the most frequently used accommodations. Many educators need training to more confidently select, implement, and evaluate the use of the read-aloud accommodation. Planning by special education leaders can help ensure that test day goes smoothly for students who need the read-aloud accommodation.

  16. Linking Languages through a Bilingual Read-Aloud Project

    Science.gov (United States)

    Lyster, Roy; Collins, Laura; Ballinger, Susan

    2009-01-01

    The present study was carried out in French immersion classrooms in an urban Quebec school board that is increasingly characterised by the heterogeneity of its French-dominant, English-dominant, and French/English bilingual student population. The study explored the extent to which a bilingual read-aloud project would (1) raise teachers' awareness…

  17. Science Language Accommodation in Elementary School Read-Alouds

    Science.gov (United States)

    Glass, Rory; Oliveira, Alandeom W.

    2014-03-01

    This study examines the pedagogical functions of accommodation (i.e. provision of simplified science speech) in science read-aloud sessions facilitated by five elementary teachers. We conceive of read-alouds as communicative events wherein teachers, faced with the task of orally delivering a science text of relatively high linguistic complexity, open up an alternate channel of communication, namely oral discussion. By doing so, teachers grant students access to a simplified linguistic input, a strategy designed to promote student comprehension of the textual contents of children's science books. It was found that nearly half (46%) of the read-aloud time was allotted to discussions with an increased percentage of less sophisticated words and reduced use of more sophisticated vocabulary than found in the books through communicative strategies such as simplified rewording, simplified definition, and simplified questioning. Further, aloud reading of more linguistically complex books required longer periods of discussion and an increased degree of teacher oral input and accommodation. We also found evidence of reversed simplification (i.e. sophistication), leading to student uptake of scientific language. The main significance of this study is that it reveals that teacher talk serves two often competing pedagogical functions (accessible communication of scientific information to students and promotion of student acquisition of the specialized language of science). It also underscores the importance of giving analytical consideration to the simplification-sophistication dimension of science classroom discourse as well as the potential of computer-based analysis of classroom discourse to inform science teaching.

  18. The Consequences of Progressive Phonological Impairment for Reading Aloud

    Science.gov (United States)

    Woollams, Anna M.; Patterson, Karalyn

    2012-01-01

    The "primary systems" view of reading disorders proposes that there are no neural regions devoted exclusively to reading, and therefore that acquired dyslexias should reliably co-occur with deficits in more general underlying capacities. This perspective predicted that surface dyslexia, a selective deficit in reading aloud "exception" words (those…

  19. Service Learning: Flooding Students with Vocabulary through Read Alouds

    Science.gov (United States)

    Holmes, Kerry; Thompson, Judith

    2014-01-01

    In the spirit of the Steven Stahl 600 Book Kid Challenge, 90 preservice teachers engaged children in 36 read-aloud sessions for a vocabulary improvement service learning project. This article describes how the preservice teachers used narrative and informational books as a vehicle for rare-word vocabulary exposure for children ages 8-12.

  20. USING THE THINK-ALOUD METHOD TODIAGNOSE READING PROBLEMS

    Institute of Scientific and Technical Information of China (English)

    Zou; Qiming

    2001-01-01

    The think-aloud method has been widely used in cognitivestudies, and in particular, in the studies of the on-goingprocesses in reading comprehension. It is an effective tool, ifused properly, in revealing how the reader processes the textinformation and solves his/her comprehension problems usingdifferent kinds of strategies during text processing. As a result,it allows us to have a glimpse of the reader’s cognitive processesduring text processing that we cannot see under other situations,and allows us to find out the processing strengths of the reader aswell as the limitations and problems of his/her processingstrategies. Therefore, it can be useful in diagnosing students’reading problems. Although the think-aloud method is popular in cognitivestudies, it is difficult to manage. This paper offers somesuggestions on designing a program for diagnosing readingproblems to control the factors that affect the think-aloudperformance.

  1. Lexical orthographic acquisition: Is handwriting better than spelling aloud?

    Directory of Open Access Journals (Sweden)

    Marie-Line eBosse

    2014-02-01

    Full Text Available Lexical orthography acquisition is currently described as the building of links between the visual forms and the auditory forms of whole words. However, a growing body of data suggests that a motor component could further be involved in orthographic acquisition. A few studies support the idea that reading plus handwriting is a better lexical orthographic learning situation than reading alone. However, these studies did not explore which of the cognitive processes involved in handwriting enhanced lexical orthographic acquisition. Some findings suggest that the specific movements memorized when learning to write may participate in the establishment of orthographic representations in memory. The aim of the present study was to assess this hypothesis using handwriting and spelling aloud as two learning conditions. In two experiments, fifth graders were asked to read complex pseudo-words embedded in short sentences. Immediately after reading, participants had to recall the pseudo-words’ spellings either by spelling them aloud or by handwriting them down. One week later, orthographic acquisition was tested using two post-tests: a pseudo-word production task (spelling by hand in Experiment 1 or spelling aloud in Experiment 2 and a pseudo-word recognition task. Results showed no significant difference in pseudo-word recognition between the two learning conditions. In the pseudo-word production task, orthography learning improved when the learning and post-test conditions were similar, thus showing a massive encoding-retrieval match effect in the two experiments. However, a mixed model analysis of the pseudo-word production results revealed a significant learning condition effect which remained after control of the encoding-retrieval match effect. This later finding suggests that orthography learning is more efficient when mediated by handwriting than by spelling aloud, whatever the post-test production task.

  2. Learning Boost C++ libraries

    CERN Document Server

    Mukherjee, Arindam

    2015-01-01

    If you are a C++ programmer who has never used Boost libraries before, this book will get you up-to-speed with using them. Whether you are developing new C++ software or maintaining existing code written using Boost libraries, this hands-on introduction will help you decide on the right library and techniques to solve your practical programming problems.

  3. Using Think Aloud Protocols to Assess E-Prescribing in Community Pharmacies

    OpenAIRE

    Olufunmilola K. Odukoya, BPharm, MS; Michelle A. Chui, PharmD, PhD

    2012-01-01

    Introduction: Think aloud protocol has rarely been used as a method of data collection in community pharmacies.Purpose: The aim of the report is to describe how think aloud protocols were used to identify issues that arise when using e-prescribing technology in pharmacies. In this paper, we report on the benefits and challenges of using think aloud protocols in pharmacies to examine the use of e-prescribing systems.Methods: Sixteen pharmacists and pharmacy technicians were recruited from seve...

  4. Primary Paralleled Isolated Boost Converter with Extended Operating Voltage Range

    DEFF Research Database (Denmark)

    Hernandez Botella, Juan Carlos; Sen, Gökhan; Mira Albert, Maria del Carmen;

    2012-01-01

    Applications requiring wide input and output voltage range cannot often be satisfied by using buck or boost derived topologies. Primary paralleled isolated boost converter (PPIBC) [1]-[2] is a high efficiency boost derived topology. This paper proposes a new operation mode for extending the input...... and output voltage range in PPIBC. The proposed solution does not modify PPIBC power stage, the converter gain is modified instead by short circuiting one of the paralleled connected primary windings present in this topology.......Applications requiring wide input and output voltage range cannot often be satisfied by using buck or boost derived topologies. Primary paralleled isolated boost converter (PPIBC) [1]-[2] is a high efficiency boost derived topology. This paper proposes a new operation mode for extending the input...

  5. Reading Culturally Relevant Literature Aloud to Urban Youths with Behavioral Challenges

    Science.gov (United States)

    Verden, Claire E.

    2012-01-01

    This article discusses the viability of reading culturally relevant literature aloud to urban middle school youth. The findings from a research study are shared and guidelines for implementing a culturally sensitive read aloud program in your own middle school or high school classroom are discussed. Anecdotes from students involved in the study…

  6. Comparison of Think-Aloud and Constructive Interaction in Usability Testing with Children

    DEFF Research Database (Denmark)

    Als, Benedikte Skibsted; Jensen, Janne Jul; Skov, Mikael B.

    2005-01-01

    Constructive interaction provides natural thinking-aloud as test subjects collaborate to solve tasks. Since children may face difficulties in following instructions for a standard think-aloud test, constructive interaction has been suggested as evaluation method when usability testing with children....... However, the relationship between think-aloud and constructive interaction is still poorly understood. We present an experiment that compares think-aloud and constructive interaction in usability testing. The experiment involves 60 children with three setups where children apply think......-aloud, and constructive interaction in acquainted and non-acquainted pairs. Our results show that the pairing of children had impact on identification of usability problems as acquainted dyads identified more problems both in total and of the most severe than non-acquainted dyads and individual testers. Finally...

  7. Scrutinising usability evaluation: does thinking aloud affect behaviour and mental workload?

    DEFF Research Database (Denmark)

    Hertzum, Morten; Hansen, Kristin Due; Andersen, Hans Henrik

    2009-01-01

    Thinking aloud is widely used for usability evaluation. The validity of the method is, however, debatable because it is generally used in a relaxed way that conflicts with the prescriptions of the classic model for obtaining valid verbalisations of thought processes. This study investigates whether...... participants that think aloud in the classic or relaxed way behave differently compared to performing in silence. Results indicate that whereas classic thinking aloud has little or no effect on behaviour apart from prolonging tasks, relaxed thinking aloud affects behaviour in multiple ways. During relaxed...... thinking aloud participants took longer to solve tasks, spent a larger part of tasks on general distributed visual behaviour, issued more commands to navigate both within and between the pages of the websites used in the experiment, and experienced higher mental workload. Implications for usability...

  8. Think aloud: acute stress and coping strategies during golf performances.

    Science.gov (United States)

    Nicholls, Adam R; Polman, Remco C J

    2008-07-01

    A limitation of the sport psychology coping literature is the amount of time between a stressful episode and the recall of the coping strategies used in the stressful event (Nicholls & Polman, 2007). The purpose of this study was to develop and implement a technique to measure acute stress and coping during performance. Five high-performance adolescent golfers took part in Level 2 verbalization think aloud trials (Ericsson & Simon, 1993), which involved participants verbalizing their thoughts, over six holes of golf. Verbal reports were audio-recorded during each performance, transcribed verbatim, and analyzed using protocol analysis (Ericsson & Simon, 1993). Stressors and coping strategies varied throughout the six holes, which support the proposition that stress and coping is a dynamic process that changes across phases of the same performance (Lazarus, 1999). The results also revealed information regarding the sequential patterning of stress and coping, suggesting that the golfers experienced up to five stressors before reporting a coping strategy. Think aloud appears a suitable method to collect concurrent stress and coping data. PMID:18612855

  9. THINK ALOUD PAIR PROBLEM SOLVING (TAPPS STRATEGY IN TEACHING READING

    Directory of Open Access Journals (Sweden)

    Muhammad Zuhri Dj

    2015-12-01

    Full Text Available This research is aim to know what extent the achievement of students’ reading comprehension by using Think Aloud Pair Problem Solving (TAPPS strategy at the tenth grade students of SMKN 3 Watampone. the objectives of the research is to know what extent the achievement of student’s reading comprehension by using Think Aloud Pair Problem Solving (TAPPS strategy. The population of this research is the tenth grade students of SMKN 3 Watampone which has 149 students. The writers applied random sampling, because the school has students more than 100 students. The X Multimedia Class is taken as the sample, because it has many students who have low values in English subject based on their teacher report. This research employs an instrument based on the problem statements investigated, It is Reading comprehension test. After several meetings, this research finds out the achievement of students’ reading comprehension significantly effective to improve the student’s reading comprehension. The result of this research shows that the mean score obtained by the students through pretest was 46.545 and posttest was 88.364; the t-test value was higher than the t-table (49.385 > 2.080. It means that there is a significant difference between the result of the students’ pretest and posttest

  10. Exploring Poetry: The Reading and Writing Connection.

    Science.gov (United States)

    Ediger, Marlow

    Connecting reading and writing has become an important trend in teaching the language arts. Poetry, as a salient facet of the reading curriculum, integrates well with different purposes in writing. Poetry read aloud to students can assist learners to enjoy reading activities and develop the feeling and aesthetic dimension of learning, among other…

  11. Using Think Aloud Protocols to Assess E-Prescribing in Community Pharmacies

    Directory of Open Access Journals (Sweden)

    Olufunmilola K. Odukoya, BPharm, MS

    2012-01-01

    Full Text Available Introduction: Think aloud protocol has rarely been used as a method of data collection in community pharmacies.Purpose: The aim of the report is to describe how think aloud protocols were used to identify issues that arise when using e-prescribing technology in pharmacies. In this paper, we report on the benefits and challenges of using think aloud protocols in pharmacies to examine the use of e-prescribing systems.Methods: Sixteen pharmacists and pharmacy technicians were recruited from seven community pharmacies in Wisconsin. Data were collected using direct observation alongside think aloud protocol. Direct observations and think aloud protocols took place between January-February, 2011. Participants were asked to verbalize their thoughts as they process electronic prescriptions.Results: Participants identified weaknesses in e-prescribing that they had previously not conceived. This created heightened awareness for vigilance when processing e-prescriptions. The main challenge with using think aloud protocols was due to interruptions in the pharmacies. Also, a few participants found it challenging to remember to continue verbalizing their thought process during think aloud sessions.Conclusion: The use of think aloud protocols as method of data collection is a new way for understanding the issues related to technology use in community pharmacy practice. Think aloud protocol was beneficial in providing objective information on e-prescribing use not solely based on pharmacist’s or technician’s opinion of the technology. This method provided detailed information on a wide variety of real time challenges with e-prescribing technology use in community pharmacies. Using this data collection method can help identify potential patient safety issues when using e-prescribing and suggestions for redesign.

  12. What do thinking-aloud participants say? A comparison of moderated and unmoderated usability sessions

    DEFF Research Database (Denmark)

    Hertzum, Morten; Borlund, Pia; Kristoffersen, Kristina Bonde

    2015-01-01

    The value of thinking aloud in usability tests depends on the content of the users’ verbalizations. We investigated moderated and unmoderated users’ verbalizations during relaxed thinking aloud (i.e., verbalization at levels 1 through 3). Verbalizations of user experience were frequent and mostly...... relevant to the identification of usability issues. Explanations and redesign proposals were also mostly relevant, but infrequent. The relevance of verbalizations of user experience, explanations, and redesign proposals showed the value of relaxed thinking aloud but did not clarify the tradeoff between...... rich verbalizations and test reactivity. Action descriptions and system observations – two verbalization categories consistent with both relaxed and classic thinking aloud – were frequent but mainly of low relevance. Across all verbalizations, the positive or negative verbalizations were more often...

  13. Adult Learning Open University Determinants (ALOUD) study: Psychological factors associated with study success

    NARCIS (Netherlands)

    Neroni, Joyce; De Groot, Renate; Kirschner, Paul A.

    2013-01-01

    Neroni, J., De Groot, R. H. M., & Kirschner, P. A. (2012, 7 November). Adult Learning Open University Determinants (ALOUD) study: Psychological factors associated with study success. Poster presentation at the International ICO Fall School, Girona, Spain.

  14. Adult Learning Open University Determinants study (ALOUD): Biological lifestyle factors associated with study success

    NARCIS (Netherlands)

    Gijselaers, Jérôme; De Groot, Renate; Kirschner, Paul A.

    2012-01-01

    Gijselaers, H. J. M., De Groot, R. H. M., & Kirschner, P. A. (2012, 7 November). Adult Learning Open University Determinants study (ALOUD): Biological lifestyle factors associated with study success. Poster presentation at the International ICO Fall School, Girona, Spain.

  15. Breast boost - why, how, when...?

    International Nuclear Information System (INIS)

    Background: Breast conservation management including tumorectomy or quadrantectomy and external beam radiotherapy with a dose of 45 to 50 Gy in the treatment of small breast carcinomas is generally accepted. The use of a radiation boost - in particular for specific subgroups - has not been clarified. With regard to the boost technique there is some controversy between groups emphasizing the value of electron boost treatment and groups pointing out the value of interstitial boost treatment. This controversy has become even more complicated as there is an increasing number of institutions reporting the use of HDR interstitial brachytherapy for boost treatment. The most critical issue with regard to interstitial HDR brachytherapy is the assumed serious long-term morbidity after a high single radiation dose as used in HDR-treatments. Methods and Results: This article gives a perspective and recommendations on some aspects of this issue (indication, timing, target volume, dose and dose rate). Conclusion: More information about the indication for a boost is to be expected from the EORTC trial 22881/10882. Careful selection of treatment procedures for specific subgroups of patients and refinement in surgical procedures and radiotherapy techniques may be useful in improving the clinical and cosmetic results in breast conservation therapy. Prospective trials comparing on the one hand different boost techniques and on the other hand particular morphologic criteria in treatments with boost and without boost are needed to give more detailed recommendations for boost indication and for boost techniques. (orig.)

  16. Diversity-Based Boosting Algorithm

    Directory of Open Access Journals (Sweden)

    Jafar A. Alzubi

    2016-05-01

    Full Text Available Boosting is a well known and efficient technique for constructing a classifier ensemble. An ensemble is built incrementally by altering the distribution of training data set and forcing learners to focus on misclassification errors. In this paper, an improvement to Boosting algorithm called DivBoosting algorithm is proposed and studied. Experiments on several data sets are conducted on both Boosting and DivBoosting. The experimental results show that DivBoosting is a promising method for ensemble pruning. We believe that it has many advantages over traditional boosting method because its mechanism is not solely based on selecting the most accurate base classifiers but also based on selecting the most diverse set of classifiers.

  17. Boosting Support Vector Machines

    Directory of Open Access Journals (Sweden)

    Elkin Eduardo García Díaz

    2006-11-01

    Full Text Available En este artículo, se presenta un algoritmo de clasificación binaria basado en Support Vector Machines (Máquinas de Vectores de Soporte que combinado apropiadamente con técnicas de Boosting consigue un mejor desempeño en cuanto a tiempo de entrenamiento y conserva características similares de generalización con un modelo de igual complejidad pero de representación más compacta./ In this paper we present an algorithm of binary classification based on Support Vector Machines. It is combined with a modified Boosting algorithm. It run faster than the original SVM algorithm with a similar generalization error and equal complexity model but it has more compact representation.

  18. Analytic Boosted Boson Discrimination

    CERN Document Server

    Larkoski, Andrew J; Neill, Duff

    2015-01-01

    Observables which discriminate boosted topologies from massive QCD jets are of great importance for the success of the jet substructure program at the Large Hadron Collider. Such observables, while both widely and successfully used, have been studied almost exclusively with Monte Carlo simulations. In this paper we present the first all-orders factorization theorem for a two-prong discriminant based on a jet shape variable, $D_2$, valid for both signal and background jets. Our factorization theorem simultaneously describes the production of both collinear and soft subjets, and we introduce a novel zero-bin procedure to correctly describe the transition region between these limits. By proving an all orders factorization theorem, we enable a systematically improvable description, and allow for precision comparisons between data, Monte Carlo, and first principles QCD calculations for jet substructure observables. Using our factorization theorem, we present numerical results for the discrimination of a boosted $Z...

  19. SUSY using boosted techniques

    CERN Document Server

    Stark, Giordon; The ATLAS collaboration

    2016-01-01

    In this talk, I present a discussion of techniques used in supersymmetry searches in papers published by the ATLAS Collaboration from late Run 1 to early Run 2. The goal is to highlight concepts the analyses have in common, why/how they work, and possible SUSY searches that could benefit from boosted studies. Theoretical background will be provided for reference to encourage participants to explore in depth on their own time.

  20. Analytic boosted boson discrimination

    OpenAIRE

    Andrew J. Larkoski; Moult, Ian; Neill, Duff

    2015-01-01

    Observables which discriminate boosted topologies from massive QCD jets are of great importance for the success of the jet substructure program at the Large Hadron Collider. Such observables, while both widely and successfully used, have been studied almost exclusively with Monte Carlo simulations. In this paper we present the first all-orders factorization theorem for a two-prong discriminant based on a jet shape variable, $D_2$, valid for both signal and background jets. Our factorization t...

  1. Connected Traveler

    Energy Technology Data Exchange (ETDEWEB)

    2016-06-01

    The Connected Traveler framework seeks to boost the energy efficiency of personal travel and the overall transportation system by maximizing the accuracy of predicted traveler behavior in response to real-time feedback and incentives. It is anticipated that this approach will establish a feedback loop that 'learns' traveler preferences and customizes incentives to meet or exceed energy efficiency targets by empowering individual travelers with information needed to make energy-efficient choices and reducing the complexity required to validate transportation system energy savings. This handout provides an overview of NREL's Connected Traveler project, including graphics, milestones, and contact information.

  2. Substructure of Boosted Jets

    CERN Document Server

    Duchovni, Ehud

    2013-01-01

    Jets with transverse energy of few TeV are becoming now common in LHC data. Most of these jets are produced by QCD processes and some from the collimated decay of highly boosted objects like W, Z, H0 and top-quark. The study of such QCD jets may shed light on QCD showering processes and the identification of the jets coming from decays may test the Standard Model under extreme conditions and may also provide the first hints for Physics Beyond the Standard Model. A short review of jet algorithms, Correction procedures for pile-up effects and commonly used substructure observables are described.

  3. Boost C++ application development cookbook

    CERN Document Server

    Polukhin, Antony

    2013-01-01

    This book follows a cookbook approach, with detailed and practical recipes that use Boost libraries.This book is great for developers new to Boost, and who are looking to improve their knowledge of Boost and see some undocumented details or tricks. It's assumed that you will have some experience in C++ already, as well being familiar with the basics of STL. A few chapters will require some previous knowledge of multithreading and networking. You are expected to have at least one good C++ compiler and compiled version of Boost (1.53.0 or later is recommended), which will be used during the exer

  4. Gradient boosting machines, a tutorial.

    Science.gov (United States)

    Natekin, Alexey; Knoll, Alois

    2013-01-01

    Gradient boosting machines are a family of powerful machine-learning techniques that have shown considerable success in a wide range of practical applications. They are highly customizable to the particular needs of the application, like being learned with respect to different loss functions. This article gives a tutorial introduction into the methodology of gradient boosting methods with a strong focus on machine learning aspects of modeling. A theoretical information is complemented with descriptive examples and illustrations which cover all the stages of the gradient boosting model design. Considerations on handling the model complexity are discussed. Three practical examples of gradient boosting applications are presented and comprehensively analyzed. PMID:24409142

  5. Gradient Boosting Machines, A Tutorial

    Directory of Open Access Journals (Sweden)

    Alexey eNatekin

    2013-12-01

    Full Text Available Gradient boosting machines are a family of powerful machine-learning techniques that have shown considerable success in a wide range of practical applications. They are highly customizable to the particular needs of the application, like being learned with respect to different loss functions. This article gives a tutorial introduction into the methodology of gradient boosting methods. A theoretical information is complemented with many descriptive examples and illustrations which cover all the stages of the gradient boosting model design. Considerations on handling the model complexity are discussed. A set of practical examples of gradient boosting applications are presented and comprehensively analyzed.

  6. Analytic boosted boson discrimination

    Science.gov (United States)

    Larkoski, Andrew J.; Moult, Ian; Neill, Duff

    2016-05-01

    Observables which discriminate boosted topologies from massive QCD jets are of great importance for the success of the jet substructure program at the Large Hadron Collider. Such observables, while both widely and successfully used, have been studied almost exclusively with Monte Carlo simulations. In this paper we present the first all-orders factorization theorem for a two-prong discriminant based on a jet shape variable, D 2, valid for both signal and background jets. Our factorization theorem simultaneously describes the production of both collinear and soft subjets, and we introduce a novel zero-bin procedure to correctly describe the transition region between these limits. By proving an all orders factorization theorem, we enable a systematically improvable description, and allow for precision comparisons between data, Monte Carlo, and first principles QCD calculations for jet substructure observables. Using our factorization theorem, we present numerical results for the discrimination of a boosted Z boson from massive QCD background jets. We compare our results with Monte Carlo predictions which allows for a detailed understanding of the extent to which these generators accurately describe the formation of two-prong QCD jets, and informs their usage in substructure analyses. Our calculation also provides considerable insight into the discrimination power and calculability of jet substructure observables in general.

  7. Exploring the Writing Process of Indonesian EFL Students: The Effectiveness of Think-Aloud Protocol

    Directory of Open Access Journals (Sweden)

    Imelda Hermilinda Abas

    2016-04-01

    Full Text Available The objectives of this study were to explore the writing process of the Indonesian English as a Foreign Language (EFL students and to find out the effectiveness of using  think-aloud protocol to understand the writing process. The data were obtained from six proficient EFL students who were doing Postgraduate English Language Studies Program in Indonesia. The participants were selected based on the following criteria: had completed a minimum of two academic writing courses, had written a thesis in English, had taught English for more than two years and considered as proficient writers based on IELTS result. The finding of the study showed that all of the participants went through the following writing process: prewriting, planning, drafting, pausing, reading, revising, editing and publishing. In addition, the think-aloud protocol had different effects on the participants. Five of the participants admitted that the think-aloud protocol had a positive effect because it helped them in organizing their thoughts and ideas. However, only one participant found thinking aloud made her difficult to focus on the writing task due to the demand to verbalize and write at the same time.Keywords: think-aloud protocol, writing process, proficient writers, English as a Foreign Language (EFL

  8. Modeling of asymmetrical boost converters

    Directory of Open Access Journals (Sweden)

    Eliana Isabel Arango Zuluaga

    2014-03-01

    Full Text Available The asymmetrical interleaved dual boost (AIDB is a fifth-order DC/DC converter designed to interface photovoltaic (PV panels. The AIDB produces small current harmonics to the PV panels, reducing the power losses caused by the converter operation. Moreover, the AIDB provides a large voltage conversion ratio, which is required to step-up the PV voltage to the large dc-link voltage used in grid-connected inverters. To reject irradiance and load disturbances, the AIDB must be operated in a closed-loop and a dynamic model is required. Given that the AIDB converter operates in Discontinuous Conduction Mode (DCM, classical modeling approaches based on Continuous Conduction Mode (CCM are not valid. Moreover, classical DCM modeling techniques are not suitable for the AIDB converter. Therefore, this paper develops a novel mathematical model for the AIDB converter, which is suitable for control-pur-poses. The proposed model is based on the calculation of a diode current that is typically disregarded. Moreover, because the traditional correction to the second duty cycle reported in literature is not effective, a new equation is designed. The model accuracy is contrasted with circuital simulations in time and frequency domains, obtaining satisfactory results. Finally, the usefulness of the model in control applications is illustrated with an application example.

  9. The eye-voice span during reading aloud

    Directory of Open Access Journals (Sweden)

    Jochen eLaubrock

    2015-09-01

    Full Text Available Although eye movements during reading are modulated by cognitive processing demands, they also reflect visual sampling of the input, and possibly preparation of output for speech or the inner voice. By simultaneously recording eye movements and the voice during reading aloud, we obtained an output measure that constrains the length of time spent on cognitive processing. Here we investigate the dynamics of the eye-voice span (EVS, the distance between eye and voice. We show that the EVS is regulated immediately during fixation of a word by either increasing fixation duration or programming a regressive eye movement against the reading direction. EVS size at the beginning of a fixation was positively correlated with the likelihood of regressions and refixations. Regression probability was further increased if the EVS was still large at the end of a fixation: if adjustment of fixation duration did not sufficiently reduce the EVS during a fixation, then a regression rather than a refixation followed with high probability. We further show that the EVS can help understand cognitive influences on fixation duration during reading: in mixed model analyses, the EVS was a stronger predictor of fixation durations than either word frequency or word length. The EVS modulated the influence of several other predictors on single fixation durations. For example, word-N frequency effects were larger with a large EVS, especially when word N-1 frequency was low. Finally, a comparison of single fixation durations during oral and silent reading showed that reading is governed by similar principles in both reading modes, although EVS maintenance and articulatory processing also cause some differences. In summary, the eye-voice span is regulated by adjusting fixation duration and/or by programming a regressive eye movement when the eye-voice span gets too large. Overall, the EVS appears to be directly related to updating of the working memory buffer during reading.

  10. Thinking Aloud in the Science Classroom: Can a literacy strategy increase student learning in science?

    Science.gov (United States)

    Mockel, Lindsey Joan

    This research study investigated the effect of using the think aloud protocol while reading informational text on students' ability to learn from text in a secondary science classroom. The participants in this study were high school students (n=47) in three classes of a mixed-grade Integrated Biology, Chemistry, and Physics course. The study tracked student achievement during a four-week curriculum unit on the theory of evolution and evidence for biological evolution. All students received instruction on using the think aloud protocol, and all students practiced the think aloud protocol when reading short articles related to scientific evidence for evolution. The researcher measured student's ability to read and understand science text by comparing scores from a reading skills pre-assessment and post-assessment from each student. Student surveys were conducted to gather feedback on the effectiveness of the strategy in teaching students to use a literacy strategy while reading science text. Data were analyzed using descriptive statistics.

  11. Ultrarelativistic boost with scalar field

    Science.gov (United States)

    Svítek, O.; Tahamtan, T.

    2016-02-01

    We present the ultrarelativistic boost of the general global monopole solution which is parametrized by mass and deficit solid angle. The problem is addressed from two different perspectives. In the first one the primary object for performing the boost is the metric tensor while in the second one the energy momentum tensor is used. Since the solution is sourced by a triplet of scalar fields that effectively vanish in the boosting limit we investigate the behavior of a scalar field in a simpler setup. Namely, we perform the boosting study of the spherically symmetric solution with a free scalar field given by Janis, Newman and Winicour. The scalar field is again vanishing in the limit pointing to a broader pattern of scalar field behaviour during an ultrarelativistic boost in highly symmetric situations.

  12. Boosted Higgs Shapes

    CERN Document Server

    Schlaffer, Matthias; Takeuchi, Michihisa; Weiler, Andreas; Wymant, Chris

    2014-01-01

    The inclusive Higgs production rate through gluon fusion has been measured to be in agreement with the Standard Model (SM). We show that even if the inclusive Higgs production rate is very SM-like, a precise determination of the boosted Higgs transverse momentum shape offers the opportunity to see effects of natural new physics. These measurements are generically motivated by effective field theory arguments and specifically in extensions of the SM with a natural weak scale, like composite Higgs models and natural supersymmetry. We show in detail how a measurement at high transverse momentum of $H\\to 2\\ell+\\mathbf{p}\\!\\!/_T$ via $H\\to \\tau\\tau$ and $H\\to WW^*$ could be performed and demonstrate that it offers a compelling alternative to the $t\\bar t H$ channel. We discuss the sensitivity to new physics in the most challenging scenario of an exactly SM-like inclusive Higgs cross-section.

  13. Boosted Higgs shapes

    Energy Technology Data Exchange (ETDEWEB)

    Schlaffer, Matthias [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Spannowsky, Michael [Durham Univ. (United Kingdom). Inst. for Particle Physics Phenomenology; Takeuchi, Michihisa [King' s College London (United Kingdom). Theoretical Physics and Cosmology Group; Weiler, Andreas [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); European Organization for Nuclear Research (CERN), Geneva (Switzerland); Wymant, Chris [Durham Univ. (United Kingdom). Inst. for Particle Physics Phenomenology; Laboratoire d' Annecy-le-Vieux de Physique Theorique, Annecy-le-Vieux (France)

    2014-05-15

    The inclusive Higgs production rate through gluon fusion has been measured to be in agreement with the Standard Model (SM). We show that even if the inclusive Higgs production rate is very SM-like, a precise determination of the boosted Higgs transverse momentum shape offers the opportunity to see effects of natural new physics. These measurements are generically motivated by effective field theory arguments and specifically in extensions of the SM with a natural weak scale, like composite Higgs models and natural supersymmetry. We show in detail how a measurement at high transverse momentum of H→2l+p{sub T} via H→ττ and H→WW{sup *} could be performed and demonstrate that it offers a compelling alternative to the t anti tH channel. We discuss the sensitivity to new physics in the most challenging scenario of an exactly SM-like inclusive Higgs cross-section.

  14. Boosted Higgs shapes

    Energy Technology Data Exchange (ETDEWEB)

    Schlaffer, Matthias [DESY, Hamburg (Germany); Spannowsky, Michael [Durham University, Department of Physics, Institute for Particle Physics Phenomenology, Durham (United Kingdom); Takeuchi, Michihisa [King' s College London, Theoretical Physics and Cosmology Group, Department of Physics, London (United Kingdom); Weiler, Andreas [DESY, Hamburg (Germany); CERN, Theory Division, Physics Department, Geneva 23 (Switzerland); Wymant, Chris [Durham University, Department of Physics, Institute for Particle Physics Phenomenology, Durham (United Kingdom); Laboratoire d' Annecy-le-Vieux de Physique Theorique, 9 Chemin de Bellevue, 74940, Annecy-le-Vieux (France); Imperial College London, Department of Infectious Disease Epidemiology, London (United Kingdom)

    2014-10-15

    The inclusive Higgs production rate through gluon fusion has been measured to be in agreement with the Standard Model (SM). We show that even if the inclusive Higgs production rate is very SM-like, a precise determination of the boosted Higgs transverse momentum shape offers the opportunity to see effects of natural new physics. These measurements are generically motivated by effective field theory arguments and specifically in extensions of the SM with a natural weak scale, like composite Higgs models and natural supersymmetry. We show in detail how a measurement at high transverse momentum of H → 2l + p{sub T} via H → ττ and H → WW* could be performed and demonstrate that it offers a compelling alternative to the t anti tH channel. We discuss the sensitivity to newphysics in the most challenging scenario of an exactly SM-like inclusive Higgs cross section. (orig.)

  15. Detection of Illegitimate Emails using Boosting Algorithm

    DEFF Research Database (Denmark)

    Nizamani, Sarwat; Memon, Nasrullah; Wiil, Uffe Kock

    2011-01-01

    spam email detection. For our desired task, we have applied a boosting technique. With the use of boosting we can achieve high accuracy of traditional classification algorithms. When using boosting one has to choose a suitable weak learner as well as the number of boosting iterations. In this paper, we...... propose a Naive Bayes classifier as a suitable weak learner for the boosting algorithm. It achieves maximum performance with very few boosting iterations....

  16. The Effect of English Verbal Songs on Connected Speech Aspects of Adult English Learners’ Speech Production

    Directory of Open Access Journals (Sweden)

    Farshid Tayari Ashtiani

    2015-02-01

    Full Text Available The present study was an attempt to investigate the impact of English verbal songs on connected speech aspects of adult English learners’ speech production. 40 participants were selected based on the results of their performance in a piloted and validated version of NELSON test given to 60 intermediate English learners in a language institute in Tehran. Then they were equally distributed in two control and experimental groups and received a validated pretest of reading aloud and speaking in English. Afterward, the treatment was performed in 18 sessions by singing preselected songs culled based on some criteria such as popularity, familiarity, amount, and speed of speech delivery, etc. In the end, the posttests of reading aloud and speaking in English were administered. The results revealed that the treatment had statistically positive effects on the connected speech aspects of English learners’ speech production at statistical .05 level of significance. Meanwhile, the results represented that there was not any significant difference between the experimental group’s mean scores on the posttests of reading aloud and speaking. It was thus concluded that providing the EFL learners with English verbal songs could positively affect connected speech aspects of both modes of speech production, reading aloud and speaking. The Findings of this study have pedagogical implications for language teachers to be more aware and knowledgeable of the benefits of verbal songs to promote speech production of language learners in terms of naturalness and fluency.Keywords: English Verbal Songs, Connected Speech, Speech Production, Reading Aloud, Speaking 

  17. A High Efficiency Power Factor Correction Using Interleaved Boost Converter With Fuzzy Logic Control

    Directory of Open Access Journals (Sweden)

    M.BHUVANESWARI

    2013-06-01

    Full Text Available This paper presents interleaved front end boost converter to perform better power factor correction to store energy for electric vehicles. The interleaved boost converter increases reliability, decreased stress on critical components, improves efficiency and more flexibility. The parallel connection of two boost converters reduces the input ripple current of the converter. The interleaved boost converter with coupled inductors reduces the volume and copper usage of the magnetic components and also achieves high power density. The coupled inductor delivers continuous current to improve the efficiency. The boost power factor correction (PFC converter with auxiliary circuit optimizes the amount of reactive current during light load condition. In addition the control system regulates the amount of reactive current to guarantee zero voltage switching (ZVS during line cycle for different load conditions. The proposed interleaved boost converter with coupled inductor was modeled and its performance is simulated and analyzed in Mat lab/Simulink environment.

  18. Physics with boosted top quarks

    CERN Document Server

    Kuutmann, Elin Bergeaas

    2014-01-01

    The production at the LHC of boosted top quarks (top quarks with a transverse momentum that greatly exceeds their rest mass) is a promising process to search for phenomena beyond the Standard Model. In this contribution several examples are discussed of new techniques to reconstruct and identify (tag) the collimated decay topology of the boosted hadronic decays of top quarks. Boosted top reconstruction techniques have been utilized in searches for new physical phenomena. An overview is given of searches by ATLAS, CDF and CMS for heavy new particles decaying into a top and an anti-top quark, vector-like quarks and supersymmetric partners to the top quark.

  19. Evaluating municipal websites: a methodological comparison of three think-aloud variants

    NARCIS (Netherlands)

    Haak, van den Maaike J.; Jong, de Menno D.T.; Schellens, Peter Jan

    2009-01-01

    Usability methods have received relatively little methodological attention within the field of E-Government. This paper aims to address this gap by reporting on a usability test of the municipal website of Deventer (the Netherlands), carried out by means of three variants of the think-aloud method (

  20. Teaching First Graders to Comprehend Complex Texts through Read-Alouds

    Science.gov (United States)

    Witte, Priscilla G.

    2016-01-01

    This formative and design study examined how the Complex Text Analysis (CTA) instructional approach provided support for first-grade students to increase their comprehension of texts of increasing complexity. The students in the diverse class participated in weekly lessons during which fictional texts were read aloud and analyzed in terms of key…

  1. Adult Learning Open University Determinants study (ALOUD): physical activity associated with study success

    NARCIS (Netherlands)

    Gijselaers, Jérôme; De Groot, Renate; Kirschner, Paul A.

    2013-01-01

    Gijselaers, H. J. M., De Groot, R. H. M., & Kirschner, P. A. (2013, 23 May). Adult Learning Open University Determinants study (ALOUD): physical activity associated with study success. Poster presentation at the annual meeting of the International Society for Behaviour on Nutrition and Physical Acti

  2. Engaging Children with Print: Building Early Literacy Skills through Quality Read-Alouds

    Science.gov (United States)

    Justice, Laura M.; Sofka, Amy E.

    2010-01-01

    Preschool teachers and early childhood professionals know that storybook reading is important, but they may not know how to maximize its benefits for later reading achievement. This indispensable guide presents research-based techniques for using reading aloud to intentionally and systematically build children's knowledge of print. Simple yet…

  3. Hypermedia Reading Strategies Used by Persian Graduate Students in TEFL: A Think-Aloud Study

    Science.gov (United States)

    Ketabi, Saeed; Ghavamnia, Maedeh; Rezazadeh, Mohsen

    2012-01-01

    This study investigated the cognitive strategies used by Persian EFL (English as a foreign language) graduate students while reading a hypermedia text. Prior to the start of the study, the Nelson-Denny Reading Test was used in order to measure the reading ability of the students. Data was collected through think-aloud protocols, and the strategies…

  4. Podcasts on Mobile Devices as a Read-Aloud Testing Accommodation in Middle School Science Assessment

    Science.gov (United States)

    McMahon, Don; Wright, Rachel; Cihak, David F.; Moore, Tara C.; Lamb, Richard

    2016-04-01

    The purpose of this study was to examine the effect of a digitized podcast to deliver read-aloud testing accommodations on mobile devices to students with disabilities and reading difficulties. The total sample for this study included 47 middle school students with reading difficulties. Of the 47 students, 16 were identified as students with disabilities who received special education services. Participants were randomly assigned to three experimental testing conditions, standard administration, teacher-controlled read-aloud in traditional group delivery format, and student-controlled read-aloud delivered as a podcast and accessed on a mobile device, and given sample end-of-year science assessments. Based on a factorial analysis of variances, with test conditions and student status as the fixed factors, both student groups demonstrated statistically significant gains based on their testing conditions. Results support the use of podcast delivery as a viable alternative to the traditional teacher-delivered read-aloud test accommodation. Conclusions are discussed in the context of universal design for learning testing accommodations for future research and practice.

  5. The Effect of Story Read-Alouds on Children's Foreign Language Development

    Science.gov (United States)

    Norato Cerón, Catalina

    2014-01-01

    This action research project examines the impact of reading stories aloud on the development of children's reading and critical thinking strategies as well as on the improvement of English as a foreign language. Analysis of journal entries and transcriptions of recordings of the sessions were used to gather the information. Data collected revealed…

  6. Using Think-Aloud Protocols to Investigate Secondary School Chemistry Teachers' Misconceptions about Chemical Equilibrium

    Science.gov (United States)

    Cheung, Derek

    2009-01-01

    Secondary school chemistry teachers' understanding of chemical equilibrium was investigated through interviews using the think-aloud technique. The interviews were conducted with twelve volunteer chemistry teachers in Hong Kong. Their teaching experience ranged from 3 to 18 years. They were asked to predict what would happen to the equilibrium…

  7. Print Referencing during Read-Alouds: A Technique for Increasing Emergent Readers' Print Knowledge

    Science.gov (United States)

    Zucker, Tricia A.; Ward, Allison E.; Justice, Laura M.

    2009-01-01

    This article describes how educators can readily increase emergent readers' print knowledge by using an evidence-based technique called print referencing to ensure that classroom read-alouds include not only a comprehension focus, but also a complementary focus on print. Print referencing was recently described in "The Reading Teacher" as an…

  8. A Think-Aloud Protocols Investigation of Dictionary Processing Strategies among Saudi EFL Students

    Science.gov (United States)

    Alhaysony, Maha

    2012-01-01

    This paper aims to examine qualitatively how Saudi EFL female students look-up word meanings in their dictionaries while reading. We aimed to identify and describe the look-up strategies used by these students. The subjects of the study were ten third-year English major students. A think-aloud protocol was used in order to gain insights into the…

  9. Fully Transparent Orthography, yet Lexical Reading Aloud: The Lexicality Effect in Italian

    Science.gov (United States)

    Pagliuca, Giovanni; Arduino, Lisa S.; Barca, Laura; Burani, Cristina

    2008-01-01

    This is the first study that reports the lexicality effect (i.e., words read better than nonwords) in Italian with fully transparent and methodologically well-controlled stimuli. We investigated how words and nonwords are read aloud in the Italian transparent orthography, in which there is an almost strict one-to-one correspondence between…

  10. Stories: A List of Stories to Tell and to Read Aloud.

    Science.gov (United States)

    Greene, Ellin, Comp.

    This booklet contains lists of folk and fairy tales, stories to be read aloud, and books of poetry for young children. It includes references to children's stories from many countries, stories of heroes and saints, and stories for special occasions. A section of source materials for the storyteller is also included along with subject and…

  11. Death Discussion in Science Read-Alouds: Cognitive, Sociolinguistic, and Moral Processes

    Science.gov (United States)

    Oliveira, Alandeom W.; Reis, Giuliano; Chaize, Daniel O.; Snyder, Michele A.

    2014-01-01

    Little research has been conducted on how to address the complex topic of death when teaching science to children. The present paper addresses this issue by examining how three elementary teachers discuss the death of wild animals during science read-aloud sessions. Our findings reveal the variety of ways in which nonhuman death can be…

  12. Distribution-Specific Agnostic Boosting

    CERN Document Server

    Feldman, Vitaly

    2009-01-01

    We consider the problem of boosting the accuracy of weak learning algorithms in the agnostic learning framework of Haussler (1992) and Kearns et al. (1992). Known algorithms for this problem (Ben-David et al., 2001; Gavinsky, 2002; Kalai et al., 2008) follow the same strategy as boosting algorithms in the PAC model: the weak learner is executed on the same target function but over different distributions on the domain. We demonstrate boosting algorithms for the agnostic learning framework that only modify the distribution on the labels of the points (or, equivalently, modify the target function). This allows boosting a distribution-specific weak agnostic learner to a strong agnostic learner with respect to the same distribution. When applied to the weak agnostic parity learning algorithm of Goldreich and Levin (1989) our algorithm yields a simple PAC learning algorithm for DNF and an agnostic learning algorithm for decision trees over the uniform distribution using membership queries. These results substantia...

  13. Gradient boosting machines, a tutorial

    OpenAIRE

    Natekin, Alexey; Knoll, Alois

    2013-01-01

    Gradient boosting machines are a family of powerful machine-learning techniques that have shown considerable success in a wide range of practical applications. They are highly customizable to the particular needs of the application, like being learned with respect to different loss functions. This article gives a tutorial introduction into the methodology of gradient boosting methods with a strong focus on machine learning aspects of modeling. A theoretical information is complemented with de...

  14. Gradient Boosting Machines, A Tutorial

    OpenAIRE

    Alexey Natekin; Alois Knoll

    2013-01-01

    Gradient boosting machines are a family of powerful machine-learning techniques that have shown considerable success in a wide range of practical applications. They are highly customizable to the particular needs of the application, like being learned with respect to different loss functions. This article gives a tutorial introduction into the methodology of gradient boosting methods. A theoretical information is complemented with many descriptive examples and illustrations which cover all th...

  15. Scalar Controlled Boost PWM Rectifier for Micro Wind Energy Systems

    Directory of Open Access Journals (Sweden)

    J. Chelladurai

    2015-05-01

    Full Text Available Uses of Permanent Magnet Synchronous Generators (PMSG are increasing in variable speed micro-Wind Energy Conversion Systems (WECS. In stand-alone or grid-connected Micro-WECS, extraction of maximum power is vital. To extract maximum power output and to obtain a constant DC bus voltage from variable magnitude and variable frequency voltage output of PMSG and generally a two stage scheme namely i conventional diode bridge rectifier and ii DC-DC Boost/Buck/Buck-Boost converters are used. In this study, a single stage Scalar Controlled PWM (SCPWM Boost Rectifier is proposed in order to minimize the current harmonics and to improve the power factor on source side. The modeling and simulation of PMSG based wind generator and SCPWM Boost rectifier was developed in MATLAB. The harmonic content in the input current waveform of the proposed SCPWM rectifier is compared with the conventional three-phase bridge rectifier. The Simulation results show the effectiveness of the PWM Boost rectifier in terms of effective utilization of source, improved efficiency and harmonic mitigation for PMSG based Wind Generator. Simulation results demonstrate the effectiveness of the proposed system in reducing the current and voltage THD on source side.

  16. Implementation of Fuzzy Logic controller in Photovoltaic Power generation using Boost Converter and Boost Inverter

    OpenAIRE

    Abubakkar Siddik A; Shangeetha M

    2012-01-01

    Increasing in power demand and shortage of conventional energy sources, researchers are focused on renewable energy. The proposed solar power generation circuit consists of solar array, boost converter and boost inverter. Low voltage, of photovoltaic array, is boosted using dc-dc boost converter to charge the battery and boost inverter convert this battery voltage to high quality sinusoidal ac voltage. The output of solar power fed from boost inverter feed to autonomous load without any inter...

  17. Resolving Boosted Jets with XCone

    CERN Document Server

    Thaler, Jesse

    2015-01-01

    We show how the recently proposed XCone jet algorithm smoothly interpolates between resolved and boosted kinematics. When using standard jet algorithms to reconstruct the decays of hadronic resonances like top quarks and Higgs bosons, one typically needs separate analysis strategies to handle the resolved regime of well-separated jets and the boosted regime of fat jets with substructure. XCone, by contrast, is an exclusive cone jet algorithm that always returns a fixed number of jets, so jet regions remain resolved even when (sub)jets are overlapping in the boosted regime. In this paper, we perform three LHC case studies---dijet resonances, Higgs decays to bottom quarks, and all-hadronic top pairs---that demonstrate the physics applications of XCone over a wide kinematic range.

  18. Boost.Asio C++ network programming

    CERN Document Server

    Torjo, John

    2013-01-01

    What you want is an easy level of abstraction, which is just what this book provides in conjunction with Boost.Asio. Switching to Boost.Asio is just a few extra #include directives away, with the help of this practical and engaging guide.This book is great for developers that need to do network programming, who don't want to delve into the complicated issues of a raw networking API. You should be familiar with core Boost concepts, such as smart pointers and shared_from_this, resource classes (noncopyable), functors and boost::bind, boost mutexes, and the boost date/time library. Readers should

  19. A boosted Kerr black hole solution and the structure of a general astrophysical black hole

    CERN Document Server

    Soares, Ivano Damião

    2016-01-01

    A solution of Einstein's vacuum field equations that describes a boosted Kerr black hole relative to an asymptotic Lorentz frame at the future null infinity is derived. The solution has three parameters (mass, rotation and boost) and corresponds to the most general configuration that an astrophysical black hole must have; it reduces to the Kerr solution when the boost parameter is zero. In this solution the ergosphere is north-south asymmetric, with dominant lobes in the direction opposite to the boost. However the event horizon, the Cauchy horizon and the ring singularity {\\bf --} which are the core of the black hole structure {\\bf --} do not alter, being independent of the boost parameter. Possible consequences for astrophysical processes connected with Penrose processes in the asymmetric ergosphere are discussed.

  20. Boosted Horizon of a Boosted Space-Time Geometry

    CERN Document Server

    Battista, Emmanuele; Scudellaro, Paolo; Tramontano, Francesco

    2015-01-01

    We apply the ultrarelativistic boosting procedure to map the metric of Schwarzschild-de Sitter spacetime into a metric describing de Sitter spacetime plus a shock-wave singularity located on a null hypersurface, by exploiting the picture of the embedding of an hyperboloid in a five-dimensional Minkowski spacetime. After reverting to the usual four-dimensional formalism, we also solve the geodesic equation and evaluate the Riemann curvature tensor of the boosted Schwarzschild-de Sitter metric by means of numerical calculations, which make it possible to reach the ultrarelativistic regime gradually by letting the boost velocity approach the speed of light. Eventually, the analysis of the Kretschmann invariant (and of the geodesic equation) shows the global structure of space- time, as we demonstrate the presence of a "scalar curvature singularity" within a 3-sphere and find that it is also possible to define what we have called "boosted horizon", a sort of elastic wall where all particles are surprisingly pushe...

  1. Nine Level Inverter with Boost Converter from Renewable Energy Source

    Directory of Open Access Journals (Sweden)

    Maruthu Pandiyan.R

    2015-01-01

    Full Text Available A new single phase nine level multilevel inverter is proposed. The input to the proposed nine level multilevel inverter is obtained from solar panel . The solar energy obtained from the solar panel is not constant and it varies with times. In order to maintain the constant voltage obtained from the solar panel the boost converter is used to maintain the constant output voltage using MPPT ( Perturb and observe algorithm algorithm. Then the buck boost converter output voltage is stored in the battery bank. Finally the battery energy is connected to the 9 level inverter circuits. The harmonics in the inverter is eliminated by using the fuzzy logic controller. The gate pulse for the multilevel inverter is given by the fuzzy logic controller which in turn reduces the harmonics in the inverter. Then the inverter output is connected to the grid are some application.

  2. Cultural cognition in the thinking-aloud method for usability evaluation

    DEFF Research Database (Denmark)

    Clemmensen, Torkil; Hertzum, Morten; Hornbæk, Kasper;

    2008-01-01

    We discuss the impact of cultural differences on usability evaluations that are based on the thinking-aloud method (TA). The term ‘cultural differences' helps distinguish differences in the perception and thinking of Westerners (people from Western Europe and US citizens with European origins......) and Easterners (people from China and the countries heavily influenced by its culture). We illustrate the impact of cultural cognition on four central elements of TA: (1) instructions and tasks, (2) the user's verbalizations, (3) the evaluator's reading of the user, and (4) the overall relationship between user...... and evaluator. In conclusion, we point to the importance of matching the task presentation to users' cultural background, the different effects of thinking aloud on task performance between Easterners and Westerners, the differences in nonverbal behaviour that affect usability problem detection, and, finally...

  3. Exploring the Writing Process of Indonesian EFL Students: The Effectiveness of Think-Aloud Protocol

    OpenAIRE

    Imelda Hermilinda Abas; Noor Hashima Abd Aziz

    2016-01-01

    The objectives of this study were to explore the writing process of the Indonesian English as a Foreign Language (EFL) students and to find out the effectiveness of using  think-aloud protocol to understand the writing process. The data were obtained from six proficient EFL students who were doing Postgraduate English Language Studies Program in Indonesia. The participants were selected based on the following criteria: had completed a minimum of two academic writing courses, had written a the...

  4. Modeling and Simulation of PMSG Wind Turbine with Boost Converter Working under Discontinuous Conduction Mode

    DEFF Research Database (Denmark)

    Qin, Nan; Xu, Zhao

    2008-01-01

    This paper describes modeling and simulation of a new design of wind turbines based on the permanent magnet synchronous generator (PMSG). The proposed design reduces the manufacture cost by connecting the PMSG to the grid through a boost converter in the DC-link that is operated in the discontinu......This paper describes modeling and simulation of a new design of wind turbines based on the permanent magnet synchronous generator (PMSG). The proposed design reduces the manufacture cost by connecting the PMSG to the grid through a boost converter in the DC-link that is operated...... in the discontinuous conducting mode (DCM). The new wind turbine model with the variable speed control of the PMSG based on duty cycle control of the boost converter has been developed in Matlab Simulink. Simulation studies show that DCM working mode of the boost converter provides more flexibility in controlling...

  5. Usability evaluation of a laboratory order entry system: cognitive walkthrough and think aloud combined.

    Science.gov (United States)

    Peute, Linda W P; Jaspers, Monique M W

    2005-01-01

    Though designing physician order entry (POE) systems has been a highly discussed research topic in the last decade, it seems that engineering POE systems that truly optimise the quality and efficiency of ordering is still a challenge. This study addresses a usability evaluation of an emerging POE for the electronically ordering of laboratory tests. By applying two complementary cognitive approaches, specifically the cognitive walkthrough and think aloud method with seven potential end users of the system, we analyzed usability problems in the prototype system and their potential effect on the quality of orders in terms of efficiency and errors in ordering. The cognitive walkthrough provided a coding scheme that was used to analyse in more detail usability errors encountered during the think aloud tests with the seven end users. The analyses revealed a total of 33 usability problems, which indeed led to inefficiency, omissions in ordering and even to cancelled orders. Most of these usability problems referred to incomprehensiveness of required actions by the user and incomprehensiveness of text used in the system. Next to the discussion of the reasons for these usability problems, the surplus value of the think aloud method as supplementary to the cognitive walkthrough in evaluating physician order entry systems is outlined in this paper. PMID:16160323

  6. The Contributions of Segmental and Suprasegmental Information in Reading Chinese Characters Aloud

    Science.gov (United States)

    Wang, Min; Li, Chuchu; Lin, Candise Y.

    2015-01-01

    The Chinese writing system provides an excellent case for testing the contribution of segmental and suprasegmental information in reading words aloud within the same language. In logographic Chinese characters, neither segmental nor tonal information is explicitly represented, whereas in Pinyin, an alphabetic transcription of the character, both are explicitly represented. Two primed naming experiments were conducted in which the targets were always written characters. When logographic characters served as the primes (Experiment 1), syllable segmental and tonal information appeared to be represented and encoded as an integral unit which in turn facilitated target character naming. When Pinyin served as the primes (Experiment 2), the explicit phonetic representation facilitated encoding of both segmental and suprasegmental information, but with later access to suprasegmental information. In addition, Chinese speakers were faster to name characters than Pinyin in a simple naming task (Experiment 3), suggesting that Pinyin may be read via a phonological assembly route, whereas characters may be read via a lexical route. Taken together, our findings point to the need to consider the contributions of both segmental and suprasegmental information and the time course in the well-established models for reading aloud, as well as the cognitive mechanisms underlying the reading aloud of logographic characters versus alphabetic Pinyin script. PMID:26551251

  7. IMPROVING ENGLISH PRONUNCIATION OF ADULT ESL LEARNERS THROUGH READING ALOUD ASSESSMENTS

    Directory of Open Access Journals (Sweden)

    Siti Nurani

    2015-12-01

    Full Text Available Communication skill nowadays becomes a must that everyone should master. The agreement of such conceptual meaning in communication should meet the same perception among speakers. One of the tools to improve one’s communication skill is by learning pronunciation through Reading Aloud for misperception emerged from mispronunciation can be avoided. This research aims at improving English pronunciation through reading aloud in the form of short texts. The research was carried out in Statistics Data Center (BPS by employing A Classroom Action Research with two cycles of assessments. There were 20 IT engineers of Networking Operation Center with various background of knowledge as an object of the research. The data was collected by observation, note taking, and test. Questionnaire is designed and administered to identify the participants’ core and frequency of English tasks and also to investigate participants’ previous experiences with English. Findings show that there is an improvement on participants’ pronunciation skill through Reading Aloud as it can be seen from the increase of a mean score on the second cycle with 77.75 that is considered as good predicate.

  8. Representing Arbitrary Boosts for Undergraduates.

    Science.gov (United States)

    Frahm, Charles P.

    1979-01-01

    Presented is a derivation for the matrix representation of an arbitrary boost, a Lorentz transformation without rotation, suitable for undergraduate students with modest backgrounds in mathematics and relativity. The derivation uses standard vector and matrix techniques along with the well-known form for a special Lorentz transformation. (BT)

  9. BIM-Boost in Nederland

    NARCIS (Netherlands)

    Berlo, L.A.H.M.

    2012-01-01

    Onlangs sloot TNO een samenwerkingsovereenkomst met brancheorganisaties in de bouwkolom waaromder Bouwend Nederland en BNA. Doel van de overeenkomst: een BIM-boost in Nederland bewerkstelligen. Een gesprek met Leon van Berlo van TNO over deze en andere BIM-actualiteiten

  10. Digitally-controlled PC-interfaced Boost Converter for Educational Purposes

    DEFF Research Database (Denmark)

    Ljusev, Petar; Andersen, Michael A. E.

    2004-01-01

    acquisition. At the end, client program is presented which uses TCP/IP connection for operating the digitally controlled boost converter over Internet. The aim of this cheap and flexible PC-interfaced boost converter bench is predominantly educational, to allow students to synthesize different digital......This paper describes implementation of a simple digital PID control algorithm for a boost converter using a cheap fixed-point 8-bit microcontroller. Serial communication to a PC server program is established for easier downloading of compensator parameters and current and voltage waveform...

  11. Boosting Applied to Word Sense Disambiguation

    OpenAIRE

    Escudero, Gerard; Marquez, Lluis; Rigau, German

    2000-01-01

    In this paper Schapire and Singer's AdaBoost.MH boosting algorithm is applied to the Word Sense Disambiguation (WSD) problem. Initial experiments on a set of 15 selected polysemous words show that the boosting approach surpasses Naive Bayes and Exemplar-based approaches, which represent state-of-the-art accuracy on supervised WSD. In order to make boosting practical for a real learning domain of thousands of words, several ways of accelerating the algorithm by reducing the feature space are s...

  12. Totally Corrective Boosting for Regularized Risk Minimization

    CERN Document Server

    Shen, Chunhua; Barnes, Nick

    2010-01-01

    Consideration of the primal and dual problems together leads to important new insights into the characteristics of boosting algorithms. In this work, we propose a general framework that can be used to design new boosting algorithms. A wide variety of machine learning problems essentially minimize a regularized risk functional. We show that the proposed boosting framework, termed CGBoost, can accommodate various loss functions and different regularizers in a totally-corrective optimization fashion. We show that, by solving the primal rather than the dual, a large body of totally-corrective boosting algorithms can actually be efficiently solved and no sophisticated convex optimization solvers are needed. We also demonstrate that some boosting algorithms like AdaBoost can be interpreted in our framework--even their optimization is not totally corrective. We empirically show that various boosting algorithms based on the proposed framework perform similarly on the UCIrvine machine learning datasets [1] that we hav...

  13. Reweighting with Boosted Decision Trees

    CERN Document Server

    Rogozhnikov, A

    2016-01-01

    Machine learning tools are commonly used in modern high energy physics (HEP) experiments. Different models, such as boosted decision trees (BDT) and artificial neural networks (ANN), are widely used in analyses and even in the software triggers. In most cases, these are classification models used to select the "signal" events from data. Monte Carlo simulated events typically take part in training of these models. While the results of the simulation are expected to be close to real data, in practical cases there is notable disagreement between simulated and observed data. In order to use available simulation in training, corrections must be introduced to generated data. One common approach is reweighting - assigning weights to the simulated events. We present a novel method of event reweighting based on boosted decision trees. The problem of checking the quality of reweighting step in analyses is also discussed.

  14. Beyond the initial 140 ms, lexical decision and reading aloud are different tasks: An ERP study with topographic analysis.

    Science.gov (United States)

    Mahé, Gwendoline; Zesiger, Pascal; Laganaro, Marina

    2015-11-15

    Most of our knowledge on the time-course of the mechanisms involved in reading derived from electrophysiological studies is based on lexical decision tasks. By contrast, very few ERP studies investigated the processes involved in reading aloud. It has been suggested that the lexical decision task provides a good index of the processes occurring during reading aloud, with only late processing differences related to task response modalities. However, some behavioral studies reported different sensitivity to psycholinguistic factors between the two tasks, suggesting that print processing could differ at earlier processing stages. The aim of the present study was thus to carry out an ERP comparison between lexical decision and reading aloud in order to determine when print processing differs between these two tasks. Twenty native French speakers performed a lexical decision task and a reading aloud task with the same written stimuli. Results revealed different electrophysiological patterns on both waveform amplitudes and global topography between lexical decision and reading aloud from about 140 ms after stimulus presentation for both words and pseudowords, i.e., as early as the N170 component. These results suggest that only very early, low-level visual processes are common to the two tasks which differ in core processes. Taken together, our main finding questions the use of the lexical decision task as an appropriate paradigm to investigate reading processes and warns against generalizing its results to word reading. PMID:26244274

  15. Incrementality in Planning of Speech During Speaking and Reading Aloud: Evidence from Eye-Tracking.

    Science.gov (United States)

    Ganushchak, Lesya Y; Chen, Yiya

    2016-01-01

    Speaking is an incremental process where planning and articulation interleave. While incrementality has been studied in reading and online speech production separately, it has not been directly compared within one investigation. This study set out to compare the extent of planning incrementality in online sentence formulation versus reading aloud and how discourse context may constrain the planning scope of utterance preparation differently in these two modes of speech planning. Two eye-tracking experiments are reported: participants either described pictures of transitive events (Experiment 1) or read aloud the written descriptions of those events (Experiment 2). In both experiments, the information status of an object character was manipulated in the discourse preceding each picture or sentence. In the Literal condition, participants heard a story where object character was literally mentioned (e.g., fly). In the No Mention condition, stories did not literally mention nor prime the object character depicted on the picture or written in the sentence. The target response was expected to have the same structure and content in all conditions (The frog catches the fly). During naming, the results showed shorter speech onset latencies in the Literal condition than in the No Mention condition. However, no significant differences in gaze durations were found. In contrast, during reading, there were no significant differences in speech onset latencies but there were significantly longer gaze durations to the target picture/word in the Literal than in the No Mention condition. Our results shot that planning is more incremental during reading than during naming and that discourse context can be helpful during speaker but may hinder during reading aloud. Taken together our results suggest that on-line planning of response is affected by both linguistic and non-linguistic factors.

  16. Incrementality in planning of speech during speaking and reading aloud: evidence from eye-tracking.

    Directory of Open Access Journals (Sweden)

    Lesya eGanushchak

    2016-01-01

    Full Text Available Speaking is an incremental process where planning and articulation interleave. While incrementality has been studied in reading and online speech production separately, it has not been directly compared within one investigation. This study set out to compare the extent of planning incrementality in online sentence formulation versus reading aloud and how discourse context may constrain the planning scope of utterance preparation differently in these two modes of speech planning. Two eye-tracking experiments are reported: participants either described pictures of transitive events (Experiment 1 or read aloud the written descriptions of those events (Experiment 2. In both experiments, the information status of an object character was manipulated in the discourse preceding each picture or sentence. In the Literal condition, participants heard a story where object character was literally mentioned (e.g., fly. In the No Mention condition, stories did not literally mention nor prime the object character depicted on the picture or written in the sentence. The target response was expected to have the same structure and content in all conditions (The frog catches the fly. During naming, the results showed shorter speech onset latencies in the Literal condition than in the No Mention condition. However, no significant differences in gaze durations were found. In contrast, during reading, there were no significant differences in speech onset latencies but there were significantly longer gaze durations to the target picture/word in the Literal than in the No Mention condition. Our results shot that planning is more incremental during reading than during naming and that discourse context can be helpful during speaker but may hinder during reading aloud. Taken together our results suggest that on-line planning of response is affected by both linguistic and non-linguistic factors.

  17. How Black women make sense of 'White' and 'Black' fashion magazines: a qualitative think aloud study.

    Science.gov (United States)

    Ogden, Jane; Russell, Sheriden

    2013-12-01

    This qualitative think aloud study explored how Black women (n = 32) processed information from a White or Black fashion magazine. Comments to the 'White' magazine were characterised by rejection, being critical of the media and ambivalence, whereas they responded to the 'Black' magazine with celebration, identification and a search for depth. Transcending these themes was their self-identity of being a Black woman that was brought to the fore either by a sense of exclusion (White magazine) or engagement (Black magazine). Such an identity provides resilience against the media's thin ideals by minimising the processes of social comparison and internalisation.

  18. Where boosted significances come from

    Science.gov (United States)

    Plehn, Tilman; Schichtel, Peter; Wiegand, Daniel

    2014-03-01

    In an era of increasingly advanced experimental analysis techniques it is crucial to understand which phase space regions contribute a signal extraction from backgrounds. Based on the Neyman-Pearson lemma we compute the maximum significance for a signal extraction as an integral over phase space regions. We then study to what degree boosted Higgs strategies benefit ZH and tt¯H searches and which transverse momenta of the Higgs are most promising. We find that Higgs and top taggers are the appropriate tools, but would profit from a targeted optimization towards smaller transverse momenta. MadMax is available as an add-on to MadGraph 5.

  19. Positive Semidefinite Metric Learning with Boosting

    OpenAIRE

    Shen, Chunhua; Kim, Junae; Wang, Lei; Hengel, Anton van den

    2009-01-01

    The learning of appropriate distance metrics is a critical problem in image classification and retrieval. In this work, we propose a boosting-based technique, termed \\BoostMetric, for learning a Mahalanobis distance metric. One of the primary difficulties in learning such a metric is to ensure that the Mahalanobis matrix remains positive semidefinite. Semidefinite programming is sometimes used to enforce this constraint, but does not scale well. \\BoostMetric is instead based on a key observat...

  20. Adaptive Sampling for Large Scale Boosting

    OpenAIRE

    Dubout, Charles; Fleuret, Francois

    2014-01-01

    Classical Boosting algorithms, such as AdaBoost, build a strong classifier without concern for the computational cost. Some applications, in particular in computer vision, may involve millions of training examples and very large feature spaces. In such contexts, the training time of off-the-shelf Boosting algorithms may become prohibitive. Several methods exist to accelerate training, typically either by sampling the features or the examples used to train the weak learners. Even if some of th...

  1. Recursive bias estimation and L2 boosting

    Energy Technology Data Exchange (ETDEWEB)

    Hengartner, Nicolas W [Los Alamos National Laboratory; Cornillon, Pierre - Andre [INRA, FRANCE; Matzner - Lober, Eric [RENNE, FRANCE

    2009-01-01

    This paper presents a general iterative bias correction procedure for regression smoothers. This bias reduction schema is shown to correspond operationally to the L{sub 2} Boosting algorithm and provides a new statistical interpretation for L{sub 2} Boosting. We analyze the behavior of the Boosting algorithm applied to common smoothers S which we show depend on the spectrum of I - S. We present examples of common smoother for which Boosting generates a divergent sequence. The statistical interpretation suggest combining algorithm with an appropriate stopping rule for the iterative procedure. Finally we illustrate the practical finite sample performances of the iterative smoother via a simulation study.

  2. Neural activation in speech production and reading aloud in native and non-native languages.

    Science.gov (United States)

    Berken, Jonathan A; Gracco, Vincent L; Chen, Jen-Kai; Soles, Jennika; Watkins, Kate E; Baum, Shari; Callahan, Megan; Klein, Denise

    2015-05-15

    We used fMRI to investigate neural activation in reading aloud in bilinguals differing in age of acquisition. Three groups were compared: French-English bilinguals who acquired two languages from birth (simultaneous), French-English bilinguals who learned their L2 after the age of 5 years (sequential), and English-speaking monolinguals. While the bilingual groups contrasted in age of acquisition, they were matched for language proficiency, although sequential bilinguals produced speech with a less native-like accent in their L2 than in their L1. Simultaneous bilinguals activated similar brain regions to an equivalent degree when reading in their two languages. In contrast, sequential bilinguals more strongly activated areas related to speech-motor control and orthographic to phonological mapping, the left inferior frontal gyrus, left premotor cortex, and left fusiform gyrus, when reading aloud in L2 compared to L1. In addition, the activity in these regions showed a significant positive correlation with age of acquisition. The results provide evidence for the engagement of overlapping neural substrates for processing two languages when acquired in native context from birth. However, it appears that the maturation of certain brain regions for both speech production and phonological encoding is limited by a sensitive period for L2 acquisition regardless of language proficiency.

  3. Neural correlates reveal sub-lexical orthography and phonology during reading aloud: A review

    Directory of Open Access Journals (Sweden)

    Kalinka eTimmer

    2014-08-01

    Full Text Available The sub-lexical conversion of graphemes-to-phonemes (GPC during reading has been investigated extensively with behavioral measures, as well as event-related potentials (ERPs. Most research utilizes silent reading (e.g., lexical decision task for which phonological activation is not a necessity. However, recent research employed reading aloud to capture sub-lexical GPC. The masked priming paradigm avoids strategic processing and is therefore well suitable for capturing sub-lexical processing instead of lexical effects. By employing ERPs, the on-line time course of sub-lexical GPC can be observed before the overt response. ERPs have revealed that besides phonological activation, as revealed by behavioral studies, there is also early orthographic activation. This review describes studies in one’s native language, in one’s second language, and in a cross-language situation. We discuss the implications the ERP results have on different (computational models. First, the ERP results show that computational models should assume an early locus of the grapheme-to-phoneme-conversion (GPC. Second, cross-language studies reveal that the phonological representations from both languages of a bilingual become activated automatically and the phonology belonging to the context is selected rapidly. Therefore, it is important to extend the scope of computational models of reading (aloud to multiple lexicons.

  4. The Time Course for Processing Vowels and Lexical Tones: Reading Aloud Thai Words.

    Science.gov (United States)

    Davis, Chris; Schoknecht, Colin; Kim, Jeesun; Burnham, Denis

    2016-06-01

    Three naming aloud experiments and a lexical decision (LD) experiment used masked priming to index the processing of written Thai vowels and tones. Thai allows for manipulation of the mapping between orthography and phonology not possible in other orthographies, for example, the use of consonants, vowels and tone markers in both horizontal and vertical orthographic positions (HOPs and VOPs). Experiment I showed that changing a vowel between prime and target slowed down target naming but changing a tone mark did not. Experiment I used an across item-design and a different number of HOPs in the way vowels and tones were specified. Experiment 2 used a within-item design and tested vowel and tone changes for both 2-HOP and 3-HOP targets separately. The 3-HOP words showed the same tone and vowel change effect as Experiment 1, whereas 2-HOP items did not. It was speculated that the 2-HOP result was due to the variable position of the vowel affecting priming. Experiment 3 employed a more stringent control over the 2-HOP vowel and tone items and found priming for the tone changes but not for vowel changes. The final experiment retested the items from Experiment 3 with the LD task and found no priming for the tone change items, indicating that the tone effect in Experiment 3 was due to processes involved in naming aloud. In all, the results supported the view that for naming a word, the development of tone information is slower than vowel information. PMID:27363253

  5. Using the Think-Aloud Technique for Determining Different Reading Strategies Used by Iranian EFL Learners

    Directory of Open Access Journals (Sweden)

    Ladan Bakhshalinezhad

    2015-06-01

    Full Text Available This study explored the reading strategies used by advanced and intermediate Persian EFL learners in both English and Persian reading comprehension texts.  Based on the aims of the study reading comprehension texts were administered to the learners and their reading strategies in both English and Persian reading comprehension texts were examined through the think-aloud method. The findings showed that while the advanced EFL learners employed all the strategies (which were included in the strategy table of the study in their English texts, the intermediate learners used only some of them and also used their strategies with different frequencies in comparison with the advanced learners. Therefore, the findings supported the view that the use of the reading strategies may be related to the learners’ proficiency level. The findings also supported the idea that reading strategies can be transferred from one language to another based on the learners’ proficiency level.Keywords: learning strategies, reading strategies, think aloud protocols, threshold level, transferability

  6. Experimentally induced distraction impacts cognitive but not emotional processes in think-aloud cognitive assessment

    Directory of Open Access Journals (Sweden)

    Kean J. Hsu

    2014-05-01

    Full Text Available Studies have examined the impact of distraction on basic task performance (e.g., working memory, motor responses, yet research is lacking regarding its impact in the domain of think-aloud cognitive assessment, where the threat to assessment validity is high. The Articulated Thoughts in Simulated Situations think-aloud cognitive assessment paradigm was employed to address this issue. Participants listened to scenarios under three conditions (i.e., while answering trivia questions, playing a visual puzzle game, or with no experimental distractor. Their articulated thoughts were then content-analyzed both by the Linguistic Inquiry and Word Count (LIWC program and by content analysis of emotion and cognitive processes conducted by trained coders. Distraction did not impact indices of emotion but did affect cognitive processes. Specifically, with the LIWC system, the trivia questions distraction condition resulted in significantly higher proportions of insight and causal words, and higher frequencies of non-fluencies (e.g., uh or umm and filler words (e.g., like or you know. Coder-rated content analysis found more disengagement and more misunderstanding particularly in the trivia questions distraction condition. A better understanding of how distraction disrupts the amount and type of cognitive engagement holds important implications for future studies employing cognitive assessment methods.

  7. Primary Parallel Isolated Boost Converter with Bidirectional Operation

    DEFF Research Database (Denmark)

    Hernandez Botella, Juan Carlos; Mira Albert, Maria del Carmen; Sen, Gökhan;

    2012-01-01

    This paper presents a bidirectional dc/dc converter operated with batteries both in the input and output. Primary parallel isolated boost converter (PPIBC) with transformer series connection on the high voltage side is preferred due to its ability to handle high currents in the low voltage side....... The converter has been modeled using non-ideal components and operated without any additional circuitry for startup using a digital soft-start procedure. Simulated and measured loop gains have been compared for the validity of the model. On-the-fly current direction change has been achieved between input...... and output battery banks with a defined ramp....

  8. Dialogic Strategies in Read-Alouds of English-Language Information Books in a Second-Grade Bilingual Classroom

    Science.gov (United States)

    Pappas, Christine C.; Varelas, Maria; Patton, Sofia Kokkino; Ye, Li; Ortiz, Ibett

    2012-01-01

    This article shows how various dialogic discourse strategies were used in read-alouds of English science information books in a 2nd-grade bilingual classroom. Using a variety of discursive strategies, Ibett encouraged her Spanish-speaking students to provide explanations and reasoning related to science ideas. Similarly, she used intertextual…

  9. Instructional Challenges in Developing Young Children's Science Concepts: Using Informational Text Read-Alouds

    Science.gov (United States)

    Hoffman, Jessica L.; Collins, Molly F.; Schickedanz, Judith A.

    2015-01-01

    Early childhood instruction tends to focus heavily on literacy development, sometimes at the expense of rich concept development (CEP, 2007; Neuman, 2006; NRC, 2012; NSTA, 2014). Because of the emphasis on literacy instruction, many early childhood teachers integrate content areas, such as science, in literacy instruction through read alouds of…

  10. Creating an Adaptive Technology Using a Cheminformatics System to Read Aloud Chemical Compound Names for People with Visual Disabilities

    Science.gov (United States)

    Kamijo, Haruo; Morii, Shingo; Yamaguchi, Wataru; Toyooka, Naoki; Tada-Umezaki, Masahito; Hirobayashi, Shigeki

    2016-01-01

    Various tactile methods, such as Braille, have been employed to enhance the recognition ability of chemical structures by individuals with visual disabilities. However, it is unknown whether reading aloud the names of chemical compounds would be effective in this regard. There are no systems currently available using an audio component to assist…

  11. Using Comic Books as Read-Alouds: Insights on Reading Instruction from an English as a Second Language Classroom

    Science.gov (United States)

    Ranker, Jason

    2007-01-01

    A first-grade teacher used comic books as read-alouds during her implementation of a reading/writing workshop. The students, primarily English-language learners, were able to make use of this medium in order to learn new reading practices. The teacher used the comics to teach multiple aspects of various reading processes such as reading with an…

  12. Flexible Strategy Use by Students Who Learn Much versus Little from Text: Transitions within Think-Aloud Protocols

    Science.gov (United States)

    Cromley, Jennifer G.; Wills, Theodore W.

    2016-01-01

    Van den Broek's landscape model explicitly posits sequences of moves during reading in real time. Two other models that implicitly describe sequences of processes during reading are tested in the present research. Coded think-aloud data from 24 undergraduate students reading scientific text were analysed with lag-sequential techniques to compare…

  13. Beyond Sentiment: A Descriptive Case Study of Elementary School Teachers' Experiences Selecting Children's Literature for Read-Alouds

    Science.gov (United States)

    Loyd, Stacy M.

    2011-01-01

    The purpose of this study was to examine how and why elementary teachers select books for the read-aloud. A phenomenological approach was used to conduct a fourteen week descriptive study. Three participants were purposefully selected to provide an in-depth examination of teachers' book selection processes. Data was collected through observations,…

  14. ALOUD psychological: Adult Learning Open University Determinants Study – Association between psychological factors and study success in formal lifelong learners

    NARCIS (Netherlands)

    Neroni, Joyce; De Groot, Renate; Kirschner, Paul A.

    2012-01-01

    Neroni, J., De Groot, R. H. M., & Kirschner, P. A. (2012, 12 April). ALOUD psychological: Adult Learning Open University Determinants Study – Association between psychological factors and study success in formal lifelong learners. Presentation given at the plenary meeting of Learning & Cognition, He

  15. ALOUD biological: Adult Learning Open University Determinants study - Association of biological determinants with study success in formal lifelong learners

    NARCIS (Netherlands)

    Gijselaers, Jérôme; De Groot, Renate; Kirschner, Paul A.

    2012-01-01

    Gijselaers, H. J. M., De Groot, R. H. M., & Kirschner, P. A. (2012, 15 March). ALOUD biological: Adult Learning Open University Determinants study - Association of biological determinants with study success in formal lifelong learners. Presentation given at the plenary meeting of Learning & Cognitio

  16. Reconceptualizing Reactivity of Think-Alouds and Eye Tracking: Absence of Evidence Is Not Evidence of Absence

    Science.gov (United States)

    Godfroid, Aline; Spino, Le Anne

    2015-01-01

    This study extends previous reactivity research on the cognitive effects of think-alouds to include eye-tracking methodology. Unlike previous studies, we supplemented traditional superiority tests with equivalence tests, because only the latter are conceptually appropriate for demonstrating nonreactivity. Advanced learners of English read short…

  17. Before They Read: Teaching Language and Literacy Development through Conversations, Interactive Read-Alouds, and Listening Games

    Science.gov (United States)

    Miller, Cathy Puett

    2010-01-01

    Preschool and kindergarten educators know that strong oral language skills must be in place before children can learn to read. In "Before They Read: Teaching Language and Literacy Development through Conversations, Interactive Read-Alouds, and Listening Games," Cathy Puett Miller helps educators teach those early literacy skills with engaging…

  18. Face Alignment Using Boosting and Evolutionary Search

    NARCIS (Netherlands)

    Zhang, Hua; Liu, Duanduan; Poel, Mannes; Nijholt, Anton; Zha, H.; Taniguchi, R.-I.; Maybank, S.

    2010-01-01

    In this paper, we present a face alignment approach using granular features, boosting, and an evolutionary search algorithm. Active Appearance Models (AAM) integrate a shape-texture-combined morphable face model into an efficient fitting strategy, then Boosting Appearance Models (BAM) consider the f

  19. ATLAS boosted object tagging 2

    CERN Document Server

    Caudron, Julien; The ATLAS collaboration

    2015-01-01

    A detailed study into the optimal techniques for identifying boosted hadronically decaying W or Z bosons is presented. Various algorithms for reconstructing, grooming and tagging bosonic jets are compared for W bosons with a wide range of transverse momenta using 8 TeV data and 8 TeV and 13 TeV MC simulations. In addition, given that a hadronic jet has been identified as resulting from the hadronic decay of a W or Z, a technique is developed to discriminate between W and Z bosons. The modeling of the tagging variables used in this technique is studied using 8 TeV pp collision data and systematic uncertainties for the tagger efficiency and fake rates are evaluated.

  20. Implementation of Fuzzy Logic controller in Photovoltaic Power generation using Boost Converter and Boost Inverter

    Directory of Open Access Journals (Sweden)

    Abubakkar Siddik A

    2012-06-01

    Full Text Available Increasing in power demand and shortage of conventional energy sources, researchers are focused on renewable energy. The proposed solar power generation circuit consists of solar array, boost converter and boost inverter. Low voltage, of photovoltaic array, is boosted using dc-dc boost converter to charge the battery and boost inverter convert this battery voltage to high quality sinusoidal ac voltage. The output of solar power fed from boost inverter feed to autonomous load without any intermediate conversion stage and a filter. For boost converter operation duty cycle is varied through fuzzy logic controller and PWM block to regulate the converter output voltage. The ac voltage total harmonic distortion (THD obtained using this configuration is quite acceptable. The proposed power generation system has several desirable features such as low cost and compact size as number of switches used, are limited to four as against six switches used in classical two-stage inverters.

  1. Orthodontics Align Crooked Teeth and Boost Self-Esteem

    Science.gov (United States)

    ... desktop! more... Orthodontics Align Crooked Teeth and Boost Self- esteem Article Chapters Orthodontics Align Crooked Teeth and Boost Self- esteem Orthodontics print full article print this chapter email ...

  2. A BOOSTING APPROACH FOR INTRUSION DETECTION

    Institute of Scientific and Technical Information of China (English)

    Zan Xin; Han Jiuqiang; Zhang Junjie; Zheng Qinghua; Han Chongzhao

    2007-01-01

    Intrusion detection can be essentially regarded as a classification problem,namely,distinguishing normal profiles from intrusive behaviors.This paper introduces boosting classification algorithm into the area of intrusion detection to learn attack signatures.Decision tree algorithm is used as simple base learner of boosting algorithm.Furthermore,this paper employs the Principle Component Analysis(PCA)approach,an effective data reduction approach,to extract the key attribute set from the original high-dimensional network traffic data.KDD CUP 99 data set is used in these exDeriments to demonstrate that boosting algorithm can greatly improve the clas.sification accuracy of weak learners by combining a number of simple"weak learners".In our experiments,the error rate of training phase of boosting algorithm is reduced from 30.2%to 8%after 10 iterations.Besides,this Daper also compares boosting algorithm with Support Vector Machine(SVM)algorithm and shows that the classification accuracy of boosting algorithm is little better than SVM algorithm's.However,the generalization ability of SVM algorithm is better than boosting algorithm.

  3. Riemann curvature of a boosted spacetime geometry

    Science.gov (United States)

    Battista, Emmanuele; Esposito, Giampiero; Scudellaro, Paolo; Tramontano, Francesco

    2016-10-01

    The ultrarelativistic boosting procedure had been applied in the literature to map the metric of Schwarzschild-de Sitter spacetime into a metric describing de Sitter spacetime plus a shock-wave singularity located on a null hypersurface. This paper evaluates the Riemann curvature tensor of the boosted Schwarzschild-de Sitter metric by means of numerical calculations, which make it possible to reach the ultrarelativistic regime gradually by letting the boost velocity approach the speed of light. Thus, for the first time in the literature, the singular limit of curvature, through Dirac’s δ distribution and its derivatives, is numerically evaluated for this class of spacetimes. Moreover, the analysis of the Kretschmann invariant and the geodesic equation shows that the spacetime possesses a “scalar curvature singularity” within a 3-sphere and it is possible to define what we here call “boosted horizon”, a sort of elastic wall where all particles are surprisingly pushed away, as numerical analysis demonstrates. This seems to suggest that such “boosted geometries” are ruled by a sort of “antigravity effect” since all geodesics seem to refuse to enter the “boosted horizon” and are “reflected” by it, even though their initial conditions are aimed at driving the particles toward the “boosted horizon” itself. Eventually, the equivalence with the coordinate shift method is invoked in order to demonstrate that all δ2 terms appearing in the Riemann curvature tensor give vanishing contribution in distributional sense.

  4. Boosting Wigner's nj-symbols

    CERN Document Server

    Speziale, Simone

    2016-01-01

    We study the SL(2,C) Clebsch-Gordan coefficients appearing in the lorentzian EPRL spin foam amplitudes for loop quantum gravity. We show how the amplitudes decompose into SU(2) nj-symbols at the vertices and integrals over boosts at the edges. The integrals define edge amplitudes that can be evaluated analytically using and adapting results in the literature, leading to a pure state sum model formulation. This procedure introduces virtual representations which, in a manner reminiscent to virtual momenta in Feynman amplitudes, are off-shell of the simplicity constraints present in the theory, but with the integrands that peak at the on-shell values. We point out some properties of the edge amplitudes which are helpful for numerical and analytical evaluations of spin foam amplitudes, and suggest among other things a simpler model useful for calculations of certain lowest order amplitudes. As an application, we estimate the large spin scaling behaviour of the simpler model, on a closed foam with all 4-valent edg...

  5. Avoiding Anemia: Boost Your Red Blood Cells

    Science.gov (United States)

    ... link, please review our exit disclaimer . Subscribe Avoiding Anemia Boost Your Red Blood Cells If you’re ... and sluggish, you might have a condition called anemia. Anemia is a common blood disorder that many ...

  6. Anemia Boosts Stroke Death Risk, Study Finds

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_160476.html Anemia Boosts Stroke Death Risk, Study Finds Blood condition ... 2016 (HealthDay News) -- Older stroke victims suffering from anemia -- a lack of red blood cells -- may have ...

  7. Riemann curvature of a boosted spacetime geometry

    CERN Document Server

    Battista, Emmanuele; Scudellaro, Paolo; Tramontano, Francesco

    2014-01-01

    The ultrarelativistic boosting procedure had been applied in the literature to map the metric of Schwarzschild-de Sitter spacetime into a metric describing de Sitter spacetime plus a shock-wave singularity located on a null hypersurface. This paper evaluates the Riemann curvature tensor of the boosted Schwarzschild-de Sitter metric by means of numerical calculations, which make it possible to reach the ultrarelativistic regime gradually by letting the boost velocity approach the speed of light. Thus, for the first time in the literature, the singular limit of curvature through Dirac's delta distribution and its derivatives is numerically evaluated for this class of spacetimes. Eventually, the analysis of the Kteschmann invariant and the geodesic equation show that the spacetime possesses a scalar curvature singularity within a 3-sphere and it is possible to define what we here call boosted horizon, a sort of elastic wall where all particles are surprisingly pushed away, as numerical analysis demonstrates. Thi...

  8. Internationalization of Boost Juice to Malaysia

    OpenAIRE

    Jane L. Menzies; Stuart C. Orr

    2014-01-01

    This case describes the process that the Australian juice retail chain, Boost Juice, has used to internationalize to Malaysia. The main objective of this case is to demonstrate good practice in regard to internationalization. The case provides the background of the juice bar industry in Malaysia and determines that it is an attractive market for new start-up juice bars. An analysis of Boost Juice's capability determined that the company utilized the skills of its staff, product innovations, b...

  9. On the generator of Lorentz boost

    Institute of Scientific and Technical Information of China (English)

    Wang Zhi-Yong; Xiong Cai-Dong

    2006-01-01

    Traditionally, the theory related to the spatial angular momentum has been studied completely, while the investigation in the generator of Lorentz boost is inadequate. This paper shows that the generator of Lorentz boost has a nontrivial physical significance: it endows a charged system with an electric moment, and has an important significance for the electrical manipulations of electron spin in spintronics. An alternative treatment and interpretation for the traditional Darwin term and spin-orbit coupling are given.

  10. Top reconstruction and boosted top experimental overview

    CERN Document Server

    Skinnari, Louise

    2015-01-01

    An overview of techniques used to reconstruct resolved and boosted top quarks is presented. Techniques for resolved top quark reconstruction include kinematic likelihood fitters and pseudo- top reconstruction. Many tools and methods are available for the reconstruction of boosted top quarks, such as jet grooming techniques, jet substructure variables, and dedicated top taggers. Different techniques as used by ATLAS and CMS analyses are described and the performance of different variables and top taggers are shown.

  11. Understanding text after severe closed-head injury: assessing inferences and memory operations with a think-aloud procedure.

    Science.gov (United States)

    Schmitter-Edgecombe, Maureen; Bales, James W

    2005-09-01

    A think-aloud method was used to examine the content of information available to working memory during narrative comprehension in a CHI population. Twenty severe CHI participants (>1 year post-injury) and 20 controls talked aloud after they read each sentence of story narratives. Trabasso and Magliano's (1996a) verbal protocol analysis was then used to code for the production of inferential and non-inferential clauses and the memory operations that supported inferential clause production. We found that CHI and control groups produced a comparable number of clauses, that inferences dominated narrative comprehension, and that both groups produced more explanatory inferences than predictive or associative inferences. Despite these qualitative similarities, the CHI group demonstrated poorer comprehension, generated proportionately fewer inferences, relied less on retrieval as a memory source for explanatory inferences, and produced more non-inferential clauses and associative inferences.

  12. Philippine campaign boosts child immunizations.

    Science.gov (United States)

    Manuel-santana, R

    1993-03-01

    In 1989, USAID awarded the Philippines a 5-year, US $50 million Child Survival Program targeting improvement in immunization coverage of children, prenatal care coverage for pregnant women, and contraceptive prevalence. Upon successful completion of performance benchmarks at the end of each year, USAID released monies to fund child survival activities for the following year. This program accomplished a major program goal, which was decentralization of health planning. The Philippine Department of Health soon incorporated provincial health planning. The Philippine Department of Health soon incorporated provincial health planning in its determination of allocation of resources. Social marketing activities contributed greatly to success in achieving the goal of boosting the immunization coverage rate for the 6 antigens listed under the Expanded Program for Immunization (51%-85% of infants, 1986-1991). In fact, rural health officers in Tarlac Province in Central Luzon went from household to household to talk to mothers about the benefits of immunizing a 1-year-old child, thereby contributing greatly to their achieving a 95% full immunization coverage rate by December 1991. Social marketing techniques included modern marketing strategies and multimedia channels. They first proved successful in metro Manila which, at the beginning of the campaign, had the lowest immunization rate of all 14 regions. Every Wednesday was designated immunization day and was when rural health centers vaccinated the children. Social marketing also successfully publicized oral rehydration therapy (ORT), breast feeding, and tuberculosis control. Another contributing factor to program success in child survival activities was private sector involvement. For example, the Philippine Pediatric Society helped to promote ORT as the preferred treatment for acute diarrhea. Further, the commercial sector distributed packets of oral rehydration salts and even advertised its own ORT product. At the end of 2

  13. Boosted Jets at the LHC

    Science.gov (United States)

    Larkoski, Andrew

    2015-04-01

    Jets are collimated streams of high-energy particles ubiquitous at any particle collider experiment and serve as proxy for the production of elementary particles at short distances. As the Large Hadron Collider at CERN continues to extend its reach to ever higher energies and luminosities, an increasingly important aspect of any particle physics analysis is the study and identification of jets, electroweak bosons, and top quarks with large Lorentz boosts. In addition to providing a unique insight into potential new physics at the tera-electron volt energy scale, high energy jets are a sensitive probe of emergent phenomena within the Standard Model of particle physics and can teach us an enormous amount about quantum chromodynamics itself. Jet physics is also invaluable for lower-level experimental issues including triggering and background reduction. It is especially important for the removal of pile-up, which is radiation produced by secondary proton collisions that contaminates every hard proton collision event in the ATLAS and CMS experiments at the Large Hadron Collider. In this talk, I will review the myriad ways that jets and jet physics are being exploited at the Large Hadron Collider. This will include a historical discussion of jet algorithms and the requirements that these algorithms must satisfy to be well-defined theoretical objects. I will review how jets are used in searches for new physics and ways in which the substructure of jets is being utilized for discriminating backgrounds from both Standard Model and potential new physics signals. Finally, I will discuss how jets are broadening our knowledge of quantum chromodynamics and how particular measurements performed on jets manifest the universal dynamics of weakly-coupled conformal field theories.

  14. BioBoost. Biomass based energy intermediates boosting bio-fuel production

    Energy Technology Data Exchange (ETDEWEB)

    Niebel, Andreas [Karlsruher Institut fuer Technologie (KIT), Karlsruhe (Germany). Institut fuer Katalyseforschung und -technologie (IKFT)

    2013-10-01

    To increase the share of biomass for renewable energy in Europe conversion pathways which are economic, flexible in feedstock and energy efficient are needed. The BioBoost project concentrates on dry and wet residual biomass and wastes as feedstock for de-central conversion by fast pyrolysis, catalytic pyrolysis and hydrothermal carbonization to the intermediate energy carriers oil, coal or slurry. Based on straw the energy density increases from 2 to 20-30 GJ/m{sup 3}, enabling central GW scale gasification plants for bio-fuel production. A logistic model for feedstock supply and connection of de-central with central conversion is set up and validated allowing the determination of costs, the number and location of de-central and central sites. Techno/economic and environmental assessment of the value chain supports the optimization of products and processes. The utilization of energy carriers is investigated in existing and coming applications of heat and power production and synthetic fuels and chemicals. (orig.)

  15. Reading Aloud Activities as a Way to Determine Students’ Narrative Template

    Directory of Open Access Journals (Sweden)

    Álvarez Valencia José Aldemar

    2004-08-01

    Full Text Available This article focuses on the description of a methodological innovation implemented in a beginner’s English class at university level in Bogotá, Colombia which had two aims: First, to explore the role of reading aloud activities in the teaching of English, and second, to describe the narrative template students use when retelling a story in writing. Data collection sources for this smallscale project incorporated class observation during the reading aloud activity, students’ written samples as the means for them to retell the story, and interviews that were held at the end of the research process. This experience allowed both the teacher and the learners to approach English and see themselves playing a different role in the classroom. Moreover, it helped students foster their communicative competence as well as their motivation toward English language learning. Thus, this study promotes pedagogical debate about literacy processes in English in adults and the applicability of this kind of innovation in an EFL context. Key words: Literacy, Reading Aloud, Storytelling, Narrative Template, English Innovation, Foreign Language-Innovation El objetivo de este artículo es describir una innovación que se implementó en un curso de inglés básico a nivel universitario en Bogotá, Colombia y el cual tuvo dos objetivos: primero, explorar el rol de de las actividades de lectura en voz alta para el aprendizaje del Inglés y segundo describir el modelo narrativo que usan los estudiantes cuando narran una historia. Los métodos de recolección de datos para este proyecto a menor escala incorporaron observación de clases durante las actividades de lectura en voz alta, producción escrita de los estudiantes como un medio para que ellos narraran las historias y entrevistas al final del proceso de investigación. Esta experiencia permitió al profesor y a los estudiantes acercase al inglés de una manera diferente y verse a sí mismos asumiendo

  16. Affective factors and strategy use in a distance language context: a pilot study using think-aloud verbal protocols

    OpenAIRE

    Hurd, Stella

    2008-01-01

    This paper reports on a small-scale ethnographic pilot study using think-aloud verbal protocols (TAPs), which was carried out with novice distance learners of French. The study aimed to extend knowledge of the distance language learner experience through allowing learners to talk freely about the positive and negative emotions they were experiencing as they tackled two designated language tasks, and the strategies they used to manage these emotions. The study was prompted by the lack of resea...

  17. Tracking down hyper-boosted top quarks

    Science.gov (United States)

    Larkoski, Andrew J.; Maltoni, Fabio; Selvaggi, Michele

    2015-06-01

    The identification of hadronically decaying heavy states, such as vector bosons, the Higgs, or the top quark, produced with large transverse boosts has been and will continue to be a central focus of the jet physics program at the Large Hadron Collider (LHC). At a future hadron collider working at an order-of-magnitude larger energy than the LHC, these heavy states would be easily produced with transverse boosts of several TeV. At these energies, their decay products will be separated by angular scales comparable to individual calorimeter cells, making the current jet substructure identification techniques for hadronic decay modes not directly employable. In addition, at the high energy and luminosity projected at a future hadron collider, there will be numerous sources for contamination including initial- and final-state radiation, underlying event, or pile-up which must be mitigated. We propose a simple strategy to tag such "hyper-boosted" objects that defines jets with radii that scale inversely proportional to their transverse boost and combines the standard calorimetric information with charged track-based observables. By means of a fast detector simulation, we apply it to top quark identification and demonstrate that our method efficiently discriminates hadronically decaying top quarks from light QCD jets up to transverse boosts of 20 TeV. Our results open the way to tagging heavy objects with energies in the multi-TeV range at present and future hadron colliders.

  18. Using Think-Aloud Protocols to Uncover Misconceptions and Improve Developmental Math Instruction: An Exploratory Study

    Directory of Open Access Journals (Sweden)

    Charles Secolsky

    2016-01-01

    Full Text Available Deficiencies in education continue to escalate around the world. The focus on outcomes assessment has narrowed instructional research and curriculum evaluation to standardized testing in certain subject areas. A prototype for a quantitative literacy assessment instrument was developed with the goal of diagnosing student misconceptions of basic mathematics content and changing instructional practices to undo the misconceptions by applying cognitive psychological theory. Two hundred thirty-eight basic math high school students and 209 remedial community college students in New Jersey and New York were administered the instrument, which had been based on coded data from think-aloud protocols. The instrument asked students to answer 20 basic mathematics items and, in addition, to evaluate four possible solution strategies. For each item, frequencies of selected solution strategies and the association between strategy selection and performance on the 20-question math test are presented as a means for improving instruction. Follow-up research is proposed for determining whether undoing the student misconceptions first before teaching material on a new unit of instruction may yield more positive student outcomes.

  19. Buck-Boost Impedance Networks

    DEFF Research Database (Denmark)

    Goh, Ailian; Gao, Feng; Loh, Pon Chiang;

    2007-01-01

    control, and push up the overall system costs. Therefore, alternative topological solutions are of interest, and should preferably be implemented using only passive LC elements and diodes, connected as unique impedance networks. A number of possible network configurations are now investigated...... in this paper, and are respectively named as Z-source, H-source, EZ-source and their respective "inverted" variants. The presented impedance networks can either be used with a traditional voltage-source or current-source inverter, and can either be powered by a voltage or current source. All impedance networks...... the practicalities and performances of the described impedance networks....

  20. Centrifugal compressor design for electrically assisted boost

    Science.gov (United States)

    Y Yang, M.; Martinez-Botas, R. F.; Zhuge, W. L.; Qureshi, U.; Richards, B.

    2013-12-01

    Electrically assisted boost is a prominent method to solve the issues of transient lag in turbocharger and remains an optimized operation condition for a compressor due to decoupling from turbine. Usually a centrifugal compressor for gasoline engine boosting is operated at high rotational speed which is beyond the ability of an electric motor in market. In this paper a centrifugal compressor with rotational speed as 120k RPM and pressure ratio as 2.0 is specially developed for electrically assisted boost. A centrifugal compressor including the impeller, vaneless diffuser and the volute is designed by meanline method followed by 3D detailed design. Then CFD method is employed to predict as well as analyse the performance of the design compressor. The results show that the pressure ratio and efficiency at design point is 2.07 and 78% specifically.

  1. Centrifugal compressor design for electrically assisted boost

    International Nuclear Information System (INIS)

    Electrically assisted boost is a prominent method to solve the issues of transient lag in turbocharger and remains an optimized operation condition for a compressor due to decoupling from turbine. Usually a centrifugal compressor for gasoline engine boosting is operated at high rotational speed which is beyond the ability of an electric motor in market. In this paper a centrifugal compressor with rotational speed as 120k RPM and pressure ratio as 2.0 is specially developed for electrically assisted boost. A centrifugal compressor including the impeller, vaneless diffuser and the volute is designed by meanline method followed by 3D detailed design. Then CFD method is employed to predict as well as analyse the performance of the design compressor. The results show that the pressure ratio and efficiency at design point is 2.07 and 78% specifically

  2. Boost Breaking in the EFT of Inflation

    CERN Document Server

    Delacretaz, Luca V; Senatore, Leonardo

    2015-01-01

    If time-translations are spontaneously broken, so are boosts. This symmetry breaking pattern can be non-linearly realized by either just the Goldstone boson of time translations, or by four Goldstone bosons associated with time translations and boosts. In this paper we extend the Effective Field Theory of Multifield Inflation to consider the case in which the additional Goldstone bosons associated with boosts are light and coupled to the Goldstone boson of time translations. The symmetry breaking pattern forces a coupling to curvature so that the mass of the additional Goldstone bosons is predicted to be equal to $\\sqrt{2}H$ in the vast majority of the parameter space where they are light. This pattern therefore offers a natural way of generating self-interacting particles with Hubble mass during inflation. After constructing the general effective Lagrangian, we study how these particles mix and interact with the curvature fluctuations, generating potentially detectable non-Gaussian signals.

  3. Improved Stereo Matching With Boosting Method

    Directory of Open Access Journals (Sweden)

    Shiny B

    2015-06-01

    Full Text Available Abstract This paper presents an approach based on classification for improving the accuracy of stereo matching methods. We propose this method for occlusion handling. This work employs classification of pixels for finding the erroneous disparity values. Due to the wide applications of disparity map in 3D television medical imaging etc the accuracy of disparity map has high significance. An initial disparity map is obtained using local or global stereo matching methods from the input stereo image pair. The various features for classification are computed from the input stereo image pair and the obtained disparity map. Then the computed feature vector is used for classification of pixels by using GentleBoost as the classification method. The erroneous disparity values in the disparity map found by classification are corrected through a completion stage or filling stage. A performance evaluation of stereo matching using AdaBoostM1 RUSBoost Neural networks and GentleBoost is performed.

  4. Diode-assisted buck-boost voltage source inverters

    DEFF Research Database (Denmark)

    Gao, F.; Loh, P.C.; Teodorescu, Remus;

    2007-01-01

    This paper proposes buck-boost voltage source inverters with a unique X-shape diode-capacitor network inserted between inverter circuitry and dc source for producing a large voltage boost gain. Comparing with other voltage buck-boost techniques, the presented topologies with only a little more...... passive components can significantly enhance voltage boost capability for dc-ac inversion. With different front-end circuitries, the diode-assisted buck-boost inverters can show different operational principle and voltage boost ratio. Carefully analyzing the operational principle for the inherent energy...

  5. Entanglement asymmetry for boosted black branes

    CERN Document Server

    Mishra, Rohit

    2016-01-01

    We study the effects of asymmetry in entanglement thermodynamics of the CFT subsystems. It is found that `boosted' $p$-branes backgrounds give rise to the first law of the entanglement thermodynamics where the CFT pressure plays decisive role in the entanglement. Two different strip like subsystems, one parallel to the boost and the other perpendicular, are studied in the perturbative regime, where $T_{thermal}\\ll T_E$. We also discuss the AdS-wave backgrounds where some universal bounds can be obtained.

  6. Three papers on boosting: an introduction

    OpenAIRE

    Koltchinskii, Vladimir; Yu, Bin

    2004-01-01

    The notion of boosting originated in the Machine Learning literature in the 1980's [VALIANT, L.G. (1984). A theory of the learnable. In Proc. 16th Annual ACM Symposium on Theory of Computing 436-445. ACM Press, New York]. The goal of boosting is to improve the generalization performance of weak (or base) learning algorithms by combining them in a certain way. The first algorithm of this type was discovered by Schapire [SCHAPIRE, R.E. (1990). The strength of weak learnability. Machine Learning...

  7. A schema theory analysis of students' think aloud protocols in an STS biology context

    Science.gov (United States)

    Quinlan, Catherine Louise

    This dissertation study is a conglomerate of the fields of Science Education and Applied Cognitive Psychology. The goal of this study is to determine what organizational features and knowledge representation patterns high school students exhibit over time for issues pertinent to science and society. Participants are thirteen tenth grade students in a diverse suburban-urban classroom in a northeastern state. Students' think alouds are recorded, pre-, post-, and late-post treatment. Treatment consists of instruction in three Science, Technology, and Society (STS) biology issues, namely the human genome project, nutrition and health, and stem cell research. Coding and analyses are performed using Marshall's knowledge representations---identification knowledge, elaboration knowledge, planning knowledge, and execution knowledge, as well as qualitative research analysis methods. Schema theory, information processing theory, and other applied cognitive theory provide a framework in which to understand and explain students' schema descriptions and progressions over time. The results show that students display five organizational features in their identification and elaboration knowledge. Students also fall into one of four categories according to if they display prior schema or no prior schema, and their orientation "for" or "against," some of the issues. Students with prior schema and orientation "against" display the most robust schema descriptions and schema progressions. Those with no prior schemas and orientation "against" show very modest schema progressions best characterized by their keyword searches. This study shows the importance in considering not only students' integrated schemas but also their individual schemes. A role for the use of a more schema-based instruction that scaffolds student learning is implicated.

  8. Taxation Policies Adjust,Motor Vehicles Boost

    Institute of Scientific and Technical Information of China (English)

    Alice

    2007-01-01

    @@ In recent years,Chinese automotive industry,as one of the pillar industries has kept on rising.In 2006,Chinese auto production ranked the third in the world.The governmental authorities are also studying the corresponding taxations to boost the healthy development of Chinese automotive industry.

  9. The Attentional Boost Effect and Context Memory

    Science.gov (United States)

    Mulligan, Neil W.; Smith, S. Adam; Spataro, Pietro

    2016-01-01

    Stimuli co-occurring with targets in a detection task are better remembered than stimuli co-occurring with distractors--the attentional boost effect (ABE). The ABE is of interest because it is an exception to the usual finding that divided attention during encoding impairs memory. The effect has been demonstrated in tests of item memory but it is…

  10. Music Might Give Babies' Language Skills a Boost

    Science.gov (United States)

    ... nlm.nih.gov/medlineplus/news/fullstory_158486.html Music Might Give Babies' Language Skills a Boost Small ... April 25, 2016 (HealthDay News) -- Can listening to music boost your baby's brainpower? Maybe, at least in ...

  11. Music Might Give Babies' Language Skills a Boost

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_158486.html Music Might Give Babies' Language Skills a Boost Small ... April 25, 2016 (HealthDay News) -- Can listening to music boost your baby's brainpower? Maybe, at least in ...

  12. 高效率高增益Boost-Flyback直流变换器%High Efficiency High Step-up Boost-Flyback DC/DC Converter

    Institute of Scientific and Technical Information of China (English)

    吴红飞; 古俊银; 张君君; 邢岩; 陈国呈

    2011-01-01

    提出一种基于Boost拓扑与反激拓扑有机组合思想的Boost-Flyback变换器,Boost环节与反激环节共用输入支路,使电感一变压器的漏感能量得以利用,消除了漏感损耗,并实现了开关管电压钳位,减小了开关管电压应力;Boost与反激环节的输出支路串联,实现了高电压增益;Boost-Flybaek变换器输入并联输出串联,进一步提高了变换器的电压增益,同时减小了输入输出电压及电流纹波。提出新拓扑的DCM-ZVS工作模式控制方法,并在开环方式下实现了输出功率的控制。详细分析拓扑的工作原理、电压增益特性及控制方%A novel Boost-Flyback converter was proposed based on the combination of Boost and Flyback topologies. The energy stored in the leakage inductance of transformer is recycled and the active switch turn-off voltage is clamped by sharing the branch of the input side of the two topologies mentioned. High voltage gain is achieved with the output of Boost and Flyback topologies connected in series. The voltage gain of the converter is further improved with two of the Boost-Flybaek topologies proposed in input-in-parallel output-in-series connected. Devices stress, output and input voltage/current ripple are reduced. An output power control and discontinued current mode-zero voltage switching (DCM-ZVS) control were proposed also. The operational principle, voltage gain characteristics and principle of DCM-ZVS control method were analyzed in detail. The experimental results based on a 230 W 30 to 380 V DC/DC prototype verify the effectiveness of the theoretical analysis.

  13. 朗读教学在英语教学中的益处%The Advantages of Aloud-reading Teaching in English Teaching

    Institute of Scientific and Technical Information of China (English)

    陈永生

    2012-01-01

    The ultimate objective of learning English is to apply it to communicate and full aloud-reading is the decisive factor in improving communicative ability. Hence, emphasizing aloud-reading and bringing the role of aloud-reading into full play is an effective way to improve English teaching competence.%我们学习英语的最终目的就是熟练地运用它来进行交际.而充分地进行朗读是提高交际能力的关键所在。所以,重视朗读,充分发挥朗读在英语教学中的作用是我们提高英语教学水平的一条有效途径。

  14. Boost Converters for Gas Electric and Fuel Cell Hybrid Electric Vehicles

    Energy Technology Data Exchange (ETDEWEB)

    McKeever, JW

    2005-06-16

    Hybrid electric vehicles (HEVs) are driven by at least two prime energy sources, such as an internal combustion engine (ICE) and propulsion battery. For a series HEV configuration, the ICE drives only a generator, which maintains the state-of-charge (SOC) of propulsion and accessory batteries and drives the electric traction motor. For a parallel HEV configuration, the ICE is mechanically connected to directly drive the wheels as well as the generator, which likewise maintains the SOC of propulsion and accessory batteries and drives the electric traction motor. Today the prime energy source is an ICE; tomorrow it will very likely be a fuel cell (FC). Use of the FC eliminates a direct drive capability accentuating the importance of the battery charge and discharge systems. In both systems, the electric traction motor may use the voltage directly from the batteries or from a boost converter that raises the voltage. If low battery voltage is used directly, some special control circuitry, such as dual mode inverter control (DMIC) which adds a small cost, is necessary to drive the electric motor above base speed. If high voltage is chosen for more efficient motor operation or for high speed operation, the propulsion battery voltage must be raised, which would require some type of two-quadrant bidirectional chopper with an additional cost. Two common direct current (dc)-to-dc converters are: (1) the transformer-based boost or buck converter, which inverts a dc voltage, feeds the resulting alternating current (ac) into a transformer to raise or lower the voltage, and rectifies it to complete the conversion; and (2) the inductor-based switch mode boost or buck converter [1]. The switch-mode boost and buck features are discussed in this report as they operate in a bi-directional chopper. A benefit of the transformer-based boost converter is that it isolates the high voltage from the low voltage. Usually the transformer is large, further increasing the cost. A useful feature

  15. Curricular impact on elementary students' images of science: Informational science text read aloud and scientific inquiry

    Science.gov (United States)

    Brown, Tammy Colburn

    Understanding what influences images elementary students create about science has been researched for 30 years. This researcher sought to understand how the way science is presented in school influences images elementary students hold about science. The study's questions included: (1) What images of science do 2nd and 4th grade students portray through dialogue as they experience read alouds of informational science texts? (2) What images of science do 2nd and 4th grade students portray through dialogue as they experience science through inquiry with manipulative objects? and (3) What lifeworld resources influence students' images of science? Drawing upon symbolic interaction within a sociocultural framework, this qualitative study began during the summer of 2005 while students were enrolled in a summer program at their school and continued into the fall of 2007. Primary data included transcripts of students' dialogue during sessions, interviews, observations, field notes, demographic data, and assessment data. The researcher conducted 3 sessions with each of 4 groups of 3 students, spending 30 minutes observing, listening, and taping students in each session. All 12 students were interviewed after each of the 3 sessions on the same day resulting in approximately 18 hours of audiotapes. The researcher met with reading coaches, parents, and the selected students' teachers. Observations of the students and teachers in the context of their school environment were also made throughout the 2006-2007 regular school year. Emergent themes suggest that despite students using process skills in both sessions, the informational book reading sessions were ritualized such that the students viewed the experience as a reading exercise only and not being a scientist. In contrast, students in the manipulative sessions saw themselves as acting like or being scientists. Last, students in both sessions drew upon funds of knowledge accrued from sociocultural influences and home

  16. Suitability of the Perceived Motivational Climate in Sport Questionnaire-2 for Dance Research: A Think Aloud Approach.

    Science.gov (United States)

    Hancox, Jennie E; Quested, Eleanor; Duda, Joan L

    2015-12-01

    The Perceived Motivational Climate in Sport Questionnaire-2 (PMCSQ-2) adapted for dance has been employed in a variety of dance settings. However, the content validity of the measure and the relevance of particular subscales (e.g., Intra-Team Member Rivalry) have been questioned. Thus, the aims of this study were twofold: first, to examine the content validity of the PMCSQ-2 and identify problematic items and the nature and frequency of such problems experienced by dancers completing the measure; and second, to determine whether the content of task-involving and ego-involving climates, as captured in the subscales of the PMCSQ-2, are relevant and meaningful in dance contexts. Think aloud interviews were conducted with 21 dancers (10 male, 11 female) representing diverse types and levels of dance experience. The interviews were transcribed verbatim and segmented into text related to each item in the PMCSQ-2. Each participant's responses were individually analyzed, with the nature and frequency of problems encountered recorded in relation to five potential causes: errors in understanding, interpretation, retrieval, judgment, and responding. Think aloud interviews revealed that 72% of the participant responses presented no problem, indicating that the measure has an acceptable degree of content validity. However, the findings highlight a number of potentially problematic areas that warrant further attention. Implications for the interpretation of previous research and the conduct of future research employing the PMCSQ-2 in dance as well as other achievement contexts (e.g., sport) are discussed. PMID:26641702

  17. QCD resummations for boosted top production

    CERN Document Server

    Ferroglia, Andrea; Scott, Darren J; Yang, Li Lin

    2015-01-01

    We present new results for QCD corrections to the top-pair invariant mass and top-quark $p_T$ distributions in boosted top-quark pair production at hadron colliders. They are derived from a formalism which allows the joint resummation of soft and small-mass logarithms at NNLL$'$ order, thus taking into account all potentially large corrections in the boosted regime, where the partonic center-of-mass energy is parameterically much larger than the mass of the top quark. We match these results with those from standard soft-gluon resummation away from the small-mass limit to NNLL order and also with NLO fixed-order calculations, so that our results are valid in the maximum possible range of phase space. The resummation effects on the $p_T$ and top-pair invariant mass distributions are significant, bringing theory predictions into better agreement with experimental data compared to pure NLO calculations.

  18. Non-boost-invariant dissipative hydrodynamics

    CERN Document Server

    Florkowski, Wojciech; Strickland, Michael; Tinti, Leonardo

    2016-01-01

    The one-dimensional non-boost-invariant evolution of the quark-gluon plasma, presumably produced during the early stages of heavy-ion collisions, is analyzed within the frameworks of viscous and anisotropic hydrodynamics. We neglect transverse dynamics and assume homogeneous conditions in the transverse plane but, differently from Bjorken expansion, we relax longitudinal boost invariance in order to study the rapidity dependence of various hydrodynamical observables. We compare the results obtained using several formulations of second-order viscous hydrodynamics with a recent approach to anisotropic hydrodynamics, which treats the large initial pressure anisotropy in a non-perturbative fashion. The results obtained with second-order viscous hydrodynamics depend on the particular choice of the second-order terms included, which suggests that the latter should be included in the most complete way. The results of anisotropic hydrodynamics and viscous hydrodynamics agree for the central hot part of the system, ho...

  19. Factorization for substructures of boosted Higgs jets

    CERN Document Server

    Isaacson, Joshua; Li, Zhao; Yuan, C -P

    2015-01-01

    We present a perturbative QCD factorization formula for substructures of an energetic Higgs jet, taking the energy profile resulting from the $H\\to b\\bar b$ decay as an example. The formula is written as a convolution of a hard Higgs decay kernel with two $b$-quark jet functions and a soft function that links the colors of the two $b$ quarks. We derive an analytical expression to approximate the energy profile within a boosted Higgs jet, which significantly differs from those of ordinary QCD jets. This formalism also extends to boosted $W$ and $Z$ bosons in their hadronic decay modes, allowing an easy and efficient discrimination of fat jets produced from different processes.

  20. Does ICT boost Dutch productivity growth?

    OpenAIRE

    Henry van der Wiel

    2001-01-01

    From an historical and international perspective, Dutch labour productivity growth rates have been lacklustre. Using a growth accounting framework, this document analyses whether ICT has recently boosted Dutch labour productivity growth, similar to developments in the US. Labour productivity growth in the Dutch market sector slightly accelerated in the second half of the 1990s. The acceleration seems to be related to the production and use of ICT. The productivity performance of the Dutch ICT...

  1. Cash boost to Great British science unveiled

    CERN Multimedia

    2002-01-01

    "Trade and Industry Secretary, Patricia Hewitt today unveiled new plans for the DTI's record science budget over the next three years, to keep Britain at the forefront of world science. The plans include funding to develop life saving new health techniques, to seek alternative energy sources, to help our rural economy, to develop the computers of tomorrow and boost business with the next generation of leading edge technologies" (1 page).

  2. Tracking down hyper-boosted top quarks

    CERN Document Server

    Larkoski, Andrew J; Selvaggi, Michele

    2015-01-01

    The identification of hadronically decaying heavy states, such as vector bosons, the Higgs, or the top quark, produced with large transverse boosts has been and will continue to be a central focus of the jet physics program at the Large Hadron Collider (LHC). At a future hadron collider working at an order-of-magnitude larger energy than the LHC, these heavy states would be easily produced with transverse boosts of several TeV. At these energies, their decay products will be separated by angular scales comparable to individual calorimeter cells, making the current jet substructure identification techniques for hadronic decay modes not directly employable. In addition, at the high energy and luminosity projected at a future hadron collider, there will be numerous sources for contamination including initial- and final-state radiation, underlying event, or pile-up which must be mitigated. We propose a simple strategy to tag such "hyper-boosted" objects that defines jets with radii that scale inversely proportion...

  3. Boosted Dark Matter at Neutrino Experiments

    CERN Document Server

    Necib, Lina; Wongjirad, Taritree; Conrad, Janet M

    2016-01-01

    Current and future neutrino experiments can be used to discover dark matter, not only in searches for dark matter annihilating to neutrinos, but also in scenarios where dark matter itself scatters off Standard Model particles in the detector. In this work, we study the sensitivity of different neutrino detectors to a class of models called boosted dark matter, in which a subdominant component of a dark sector acquires a large Lorentz boost today through annihilation of a dominant component in a dark matter-dense region, such as the galactic center or dwarf spheroidal galaxies. This analysis focuses on the sensitivity of different neutrino detectors, specifically the Cherenkov-based Super-K and the future argon-based DUNE to boosted dark matter that scatters off electrons. We study the dependence of the expected limits on the experimental features, such as energy threshold, volume and exposure in the limit of constant scattering amplitude. We highlight experiment-specific features that enable current and futur...

  4. Exposure fusion using boosting Laplacian pyramid.

    Science.gov (United States)

    Shen, Jianbing; Zhao, Ying; Yan, Shuicheng; Li, Xuelong

    2014-09-01

    This paper proposes a new exposure fusion approach for producing a high quality image result from multiple exposure images. Based on the local weight and global weight by considering the exposure quality measurement between different exposure images, and the just noticeable distortion-based saliency weight, a novel hybrid exposure weight measurement is developed. This new hybrid weight is guided not only by a single image's exposure level but also by the relative exposure level between different exposure images. The core of the approach is our novel boosting Laplacian pyramid, which is based on the structure of boosting the detail and base signal, respectively, and the boosting process is guided by the proposed exposure weight. Our approach can effectively blend the multiple exposure images for static scenes while preserving both color appearance and texture structure. Our experimental results demonstrate that the proposed approach successfully produces visually pleasing exposure fusion images with better color appearance and more texture details than the existing exposure fusion techniques and tone mapping operators. PMID:25137687

  5. b-tagging in boosted topologies

    CERN Document Server

    CMS Collaboration

    2015-01-01

    As the LHC explores a new energy regime, searches for physics beyond the Standard Model at high mass scale will probe objects produced with a momentum considerably higher than their mass, modifying in a very appreciable way the event topology. The decay products of boosted objects will be collimated into a smaller area such that they could be merged within a single \\emph{fat} jet. Highly boosted objects represent a challenge to the standard jet algorithm, object identification and isolation criteria, developed for decaying particles approximately at rest in the laboratory frame. For larger boosts above order of $p_T>$200 GeV, the final state from the $H\\rightarrow b\\bar{b}$ or $t\\rightarrow bW$ decay can merge into a single jet and the approach to reconstruct the Higgs boson or top quark in this environment should change drastically. Rather than attempting to resolve jets individually, the decaying object is reconstructed as a single fat jet. Then, the composite nature of the jet is revealed by analyzing its ...

  6. Taxonomies in L1 and L2 Reading Strategies: A Critical Review of Issues Surrounding Strategy-Use Definitions and Classifications in Previous Think-Aloud Research

    Science.gov (United States)

    Alkhaleefah, Tarek A.

    2016-01-01

    Considering the various classifications of L1 and L2 reading strategies in previous think-aloud studies, the present review aims to provide a comprehensive look into those various taxonomies reported in major L1 and L2 reading studies. The rationale for this review is not only to offer a comprehensive overview of the different classifications in…

  7. Paper Partners: A Peer-Led Talk-Aloud Academic Writing Program for Students Whose First Language of Academic Study Is Not English

    Science.gov (United States)

    Vechter, Andrea; Brierley, Christopher

    2009-01-01

    This article examines the Paper Partners program at Ryerson University, Toronto. This peer-mentoring program was developed to support the academic writing skills of students whose first language of academic study was not English. The program integrated a team of student-facilitators, a talk-aloud co-editing process, and a reflective feedback…

  8. The Growing Trend of Reading Movements in Japan: Animacion a la Lectura, Ten-Minutes Reading in the Morning, and Reading Aloud by Parents.

    Science.gov (United States)

    Adachi, Sachiko

    This study examines the growing trend of reading movements in Japan and their origins. There are three main movements: Animacion a la Lectura; Ten-Minutes Reading in the Morning; and Reading Aloud by Parents in schools. This paper reports on the three movements from a review of the literature, personal observations, and practice. The paper…

  9. The ALOUD Study: Adult Open University Determinants Study - Influence of psychological determinants on academic achievement in formal lifelong learning in adults

    NARCIS (Netherlands)

    Neroni, Joyce; De Groot, Renate; Kirschner, Paul A.

    2011-01-01

    Neroni, J., De Groot, R. H. M., & Kirschner, P. A. (2011, October). The ALOUD Study: Adult Learning Open University Determinants Study - Influence of psychological determinants on academic achievement in formal lifelong learning in adults. Presentation at the second meeting of the ICO Introduction C

  10. Intertextuality in Read-Alouds of Integrated Science-Literacy Units in Urban Primary Classrooms: Opportunities for the Development of Thought and Language

    Science.gov (United States)

    Varelas, Maria; Pappas, Christine C.

    2006-01-01

    The nature and evolution of intertextuality was studied in 2 urban primary-grade classrooms, focusing on read-alouds of an integrated science-literacy unit. The study provides evidence that both debunks deficit theories for urban children by highlighting funds of knowledge that these children bring to the classroom and the sense they make of them…

  11. ALOUD: Adult Learning Open University Determinants Study: Association between biological and psychological determinants and study success in adult formal distance education

    NARCIS (Netherlands)

    De Groot, Renate; Neroni, Joyce; Gijselaers, Jérôme; Kirschner, Paul A.

    2012-01-01

    De Groot, R. H. M., Neroni, J., Gijselaers, J., & Kirschner, P. A. (2012, 6 December). ALOUD: Adult Learning Open University Determinants Study: Associations between biological and psychological determinants and study success in adult formal distance education. Presented at the Open University for t

  12. The ALOUD Study: Adult Learning Open University Determinants Study - Influence of biological and psychological determinants on study success in formal lifelong learning in adults

    NARCIS (Netherlands)

    Gijselaers, Jérôme; Neroni, Joyce; De Groot, Renate; Kirschner, Paul A.

    2011-01-01

    Gijselaers, H. J. M., Neroni, J., De Groot, R. H. M., & Kirschner, P. A. (2011, September). The ALOUD Study: Adult Learning Open University Determinants Study - Influence of biological and psychological determinants on study success in formal lifelong learning in adults. Presentation given for visit

  13. A Qualitative Study in a Rural Community: Investigating the Attitudes, Beliefs, and Interactions of Young Children and Their Parents regarding Storybook Read Alouds

    Science.gov (United States)

    Barnyak, Natalie Conrad

    2011-01-01

    This qualitative study describes the physical and verbal interactions of rural children and their parents regarding reading books aloud. The participants' attitudes and beliefs about sharing storybooks are also explored. The theoretical framework is based upon Bronfenbrenner's Ecological Model. One interview was conducted with each participant and…

  14. New Primary-Parallel Boost Converter for High-Power High-Gain Applications

    DEFF Research Database (Denmark)

    Nymand, Morten; Andersen, Michael A. E.

    2009-01-01

    Abstract—A new simple and low cost method for paralleling multiple power stages in high-power high-gain isolated full-bridge boost converters is presented. A small current balancing transformer and serial connection of transformer secondary windings provides ideal current sharing between paralleled...... and manufacturing. Extension of the principle to other isolated boost converter topologies are demonstrated as well as extension to higher numbers of parallel operated power stages. Test results from a 3 kW experimental prototype converter are presented, verifying converter operation and demonstrating current...... sharing capability. Very high converter efficiency is achieved. Worst case efficiency at minimum input voltage and maximum power is 96.9 %. Maximum efficiency is 98 %....

  15. The influence of the boost in breast-conserving therapy on cosmetic outcome in the EORTC 'boost versus no boost' trial

    International Nuclear Information System (INIS)

    Purpose: To evaluate the influence of a radiotherapy boost on the cosmetic outcome after 3 years of follow-up in patients treated with breast-conserving therapy (BCT). Methods and Materials: In EORTC trial 22881/10882, 5569 Stage I and II breast cancer patients were treated with tumorectomy and axillary dissection, followed by tangential irradiation of the breast to a dose of 50 Gy in 5 weeks, at 2 Gy per fraction. Patients having a microscopically complete tumor excision were randomized between no boost and a boost of 16 Gy. The cosmetic outcome was evaluated by a panel, scoring photographs of 731 patients taken soon after surgery and 3 years later, and by digitizer measurements, measuring the displacement of the nipple of 3000 patients postoperatively and of 1141 patients 3 years later. Results: There was no difference in the cosmetic outcome between the two treatment arms after surgery, before the start of radiotherapy. At 3-year follow-up, both the panel evaluation and the digitizer measurements showed that the boost had a significant adverse effect on the cosmetic result. The panel evaluation at 3 years showed that 86% of patients in the no-boost group had an excellent or good global result, compared to 71% of patients in the boost group (p = 0.0001). The digitizer measurements at 3 years showed a relative breast retraction assessment (pBRA) of 7.6 pBRA in the no-boost group, compared to 8.3 pBRA in the boost group, indicating a worse cosmetic result in the boost group at follow-up (p = 0.04). Conclusions: These results showed that a boost dose of 16 Gy had a negative, but limited, impact on the cosmetic outcome after 3 years

  16. Boost matrix converters in clean energy systems

    Science.gov (United States)

    Karaman, Ekrem

    This dissertation describes an investigation of novel power electronic converters, based on the ultra-sparse matrix topology and characterized by the minimum number of semiconductor switches. The Z-source, Quasi Z-source, Series Z-source and Switched-inductor Z-source networks were originally proposed for boosting the output voltage of power electronic inverters. These ideas were extended here on three-phase to three-phase and three-phase to single-phase indirect matrix converters. For the three-phase to three-phase matrix converters, the Z-source networks are placed between the three-switch input rectifier stage and the output six-switch inverter stage. A brief shoot-through state produces the voltage boost. An optimal pulse width modulation technique was developed to achieve high boosting capability and minimum switching losses in the converter. For the three-phase to single-phase matrix converters, those networks are placed similarly. For control purposes, a new modulation technique has been developed. As an example application, the proposed converters constitute a viable alternative to the existing solutions in residential wind-energy systems, where a low-voltage variable-speed generator feeds power to the higher-voltage fixed-frequency grid. Comprehensive analytical derivations and simulation results were carried out to investigate the operation of the proposed converters. Performance of the proposed converters was then compared between each other as well as with conventional converters. The operation of the converters was experimentally validated using a laboratory prototype.

  17. Connected Traveler

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, Alex

    2015-11-01

    The Connected Traveler project is a multi-disciplinary undertaking that seeks to validate potential for transformative transportation system energy savings by incentivizing efficient traveler behavior. This poster outlines various aspects of the Connected Traveler project, including market opportunity, understanding traveler behavior and decision-making, automation and connectivity, and a projected timeline for Connected Traveler's key milestones.

  18. Zhenhai to Boost Crude on Rising Demand

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    @@ Zhenhai Refining & Chemical plans to boost July crude throughput by at least 5 percent from June due to expectations of a rise in domestic demand, an industry official said on June 24. The forecast July level could match the refinery's April throughput at 1.06 million tons, the highest so far in 2003, an official close to the refinery's operations said, adding "China could see a big rise in demand from domestic travels next month especially after Beijing was dropped off the travel warning list."

  19. BOOSTING CED USING ROBUST ORIENTATION ESTIMATION

    Directory of Open Access Journals (Sweden)

    Tariq M. Khan

    2014-05-01

    Full Text Available In this paper, Coherence Enhancement Diffusion (CED is boosted feeding external orientation using new robust orientation estimation. In CED, proper scale selection is very important as the gradient vector at that scale reflects the orientation of local ridge. For this purpose a new scheme is proposed in which pre calculated orientation, by using local and integration scales. From the experiments it is found the proposed scheme is working much better in noisy environment as compared to the traditional Coherence Enhancement Diffusion

  20. Mixed Lorentz boosted $Z^{0}'s$

    CERN Document Server

    Kjaer, N J

    2001-01-01

    A novel technique is proposed to study systematic errors on jet reconstruction in W physics measurements at LEP2 with high statistical precision. The method is based on the emulation of W pair events using Mixed Lorentz Boosted Z0 events. The scope and merits of the method and its statistical accuracy are discussed in the context of the DELPHI W mass measurement in the fully hadronic channel. The numbers presented are preliminary in the sense that they do not constitute the final DELPHI systematic errors.

  1. A Composite PWM Control Strategy for Boost Converter

    Science.gov (United States)

    Qingfeng, Liu; Zhaoxia, Leng; Jinkun, Sun; Huamin, Wang

    In order to improve the control performance of boost converter with large signal disturbance, a composite PWM control strategy for boost converter operating in continuous condition mode (CCM) was proposed in this paper. The parasitical loss of Boost converter was analyzed and a loss compensation strategy was adopted to design feed-forward tracker for converter. The composite PWM controller consisted of the tracker and PID controller. Simulation and experiment results validated the validity of the control strategy presented in this paper.

  2. Precision Jet Substructure from Boosted Event Shapes

    CERN Document Server

    Feige, Ilya; Stewart, Iain; Thaler, Jesse

    2012-01-01

    Jet substructure has emerged as a critical tool for LHC searches, but studies so far have relied heavily on shower Monte Carlos, which formally approximate QCD at leading-log level. We demonstrate that systematic higher-order QCD computations of jet substructure can be carried out by boosting global event shapes by a large momentum Q, and accounting for effects due to finite jet size, initial state radiation (ISR), and underlying event (UE) as 1/Q corrections. In particular, we compute the 2-subjettiness substructure distribution for boosted Z -> q qbar events at the LHC at next-to-next-to-next-to-leading log order. The calculation is greatly simplified by recycling known results for the thrust distribution in e+ e- collisions. The 2-subjettiness distribution quickly saturates, becoming Q independent for Q > 400 GeV. Crucially, the effects of jet contamination from ISR/UE can be subtracted out analytically at large Q, without knowing their detailed form. Amusingly, the Q=infinity and Q=0 distributions are rel...

  3. A multiview boosting approach to tissue segmentation

    Science.gov (United States)

    Kwak, Jin Tae; Xu, Sheng; Pinto, Peter A.; Turkbey, Baris; Bernardo, Marcelino; Choyke, Peter L.; Wood, Bradford J.

    2014-04-01

    Digitized histopathology images have a great potential for improving or facilitating current assessment tools in cancer pathology. In order to develop accurate and robust automated methods, the precise segmentation of histologic objects such epithelium, stroma, and nucleus is necessary, in the hopes of information extraction not otherwise obvious to the subjective eye. Here, we propose a multivew boosting approach to segment histology objects of prostate tissue. Tissue specimen images are first represented at different scales using a Gaussian kernel and converted into several forms such HSV and La*b*. Intensity- and texture-based features are extracted from the converted images. Adopting multiview boosting approach, we effectively learn a classifier to predict the histologic class of a pixel in a prostate tissue specimen. The method attempts to integrate the information from multiple scales (or views). 18 prostate tissue specimens from 4 patients were employed to evaluate the new method. The method was trained on 11 tissue specimens including 75,832 epithelial and 103,453 stroma pixels and tested on 55,319 epithelial and 74,945 stroma pixels from 7 tissue specimens. The technique showed 96.7% accuracy, and as summarized into a receiver operating characteristic (ROC) plot, the area under the ROC curve (AUC) of 0.983 (95% CI: 0.983-0.984) was achieved.

  4. A Magnetohydrodynamic Boost for Relativistic Jets

    Science.gov (United States)

    Mizuno, Yosuke; Hardee, Philip; Hartmann, Dieter H.; Nishikawa, Ken-Ichi; Zhang, Bing

    2007-01-01

    We performed relativistic magnetohydrodynamic simulations of the hydrodynamic boosting mechanism for relativistic jets explored by Aloy & Rezzolla (2006) using the RAISHIN code. Simulation results show that the presence of a magnetic field changes the properties of the shock interface between the tenuous, overpressured jet (V^z j) flowing tangentially to a dense external medium. We find that magnetic fields can lead to more efficient acceleration of the jet, in comparison to the pure-hydrodynamic case. A "poloidal" magnetic field (B^z), tangent to the interface and parallel to the jet flow, produces both a stronger outward moving shock and a stronger inward moving rarefaction wave. This leads to a large velocity component normal to the interface in addition to acceleration tangent to the interface, and the jet is thus accelerated to larger Lorentz factors than those obtained in the pure-hydrodynamic case. Likewise, a strong "toroidal" magnetic field (B^y), tangent to the interface but perpendicular to the jet flow, also leads to stronger acceleration tangent to the shock interface relative to the pure-hydrodynamic case. Thus. the presence and relative orientation of a magnetic field in relativistic jets can significant modify the hydrodynamic boost mechanism studied by Aloy & Rezzolla (2006).

  5. Brain glucosamine boosts protective glucoprivic feeding.

    Science.gov (United States)

    Osundiji, Mayowa A; Zhou, Ligang; Shaw, Jill; Moore, Stephen P; Yueh, Chen-Yu; Sherwin, Robert; Heisler, Lora K; Evans, Mark L

    2010-04-01

    The risk of iatrogenic hypoglycemia is increased in diabetic patients who lose defensive glucoregulatory responses, including the important warning symptom of hunger. Protective hunger symptoms during hypoglycemia may be triggered by hypothalamic glucose-sensing neurons by monitoring changes downstream of glucose phosphorylation by the specialized glucose-sensing hexokinase, glucokinase (GK), during metabolism. Here we investigated the effects of intracerebroventricular (ICV) infusion of glucosamine (GSN), a GK inhibitor, on food intake at normoglycemia and protective feeding responses during glucoprivation and hypoglycemia in chronically catheterized rats. ICV infusion of either GSN or mannoheptulose, a structurally different GK inhibitor, dose-dependently stimulated feeding at normoglycemia. Consistent with an effect of GSN to inhibit competitively glucose metabolism, ICV coinfusion of d-glucose but not l-glucose abrogated the orexigenic effect of ICV GSN at normoglycemia. Importantly, ICV infusion of a low GSN dose (15 nmol/min) that was nonorexigenic at normoglycemia boosted feeding responses to glucoprivation in rats with impaired glucose counterregulation. ICV infusion of 15 nmol/min GSN also boosted feeding responses to threatened hypoglycemia in rats with defective glucose counterregulation. Altogether our findings suggest that GSN may be a potential therapeutic candidate for enhancing defensive hunger symptoms during hypoglycemia.

  6. Boosted Higgs boson tagging using jet substructures

    CERN Document Server

    Shvydkin, Pavel

    2016-01-01

    Searching BSM particles via the Higgs boson final state has now become common. The mass of desired BSM particle is more than 1 TeV, thereby its decay products are highly Lorentz-boosted. Hence the jets from b quark-antiquark pair - which the Higgs boson mostly decays into - are very closed to each other, and merged into one jet, that is typically reconstructed using large jet sizes (∆R = 0.8). In this work regression technique is applied to AK8 jets (which defined by anti-kT algorithm, using ΔR = 0.8). The regression makes use of boosted jets with substructure information, coupled with the pecularities of a b quark decay, like the presence of a soft lepton (SL) inside the jet. It has allowed to improve the resolution of the mass reconstruction and transverse momentum of the Higgs boson. This application results in improvement of the mass reconstruction by 3-4 percent. These result may be improved firstly by making more careful pileup rejection. Then it is possible to combine base regression train for dif...

  7. Using Read-Alouds to Help Struggling Readers Access and Comprehend Complex, Informational Text

    Science.gov (United States)

    Santoro, Lana Edwards; Baker, Scott K.; Fien, Hank; Smith, Jean Louise M.; Chard, David J.

    2016-01-01

    The use of informational texts in the elementary grades provides a context for helping students develop content understanding and domain knowledge across a wide range of subject matter. Reading informational text also provides students with the language of thought, foundational vocabulary that can be connected to other words, and technical content…

  8. Basic MOSFET Based vs Couple-coils Boost Converters for Photovoltaic Generators

    Directory of Open Access Journals (Sweden)

    Pierre Petit

    2014-02-01

    Full Text Available Considering the optimization of a photovoltaic system, several studies show the advantage in the choice of a distributed structure. For such structures small power converters such as the boosts and buck converters appear as most appropriate. We have analysed the efficiency of small power boost-converters especially dedicated for photovoltaic energy conversion systems working in the middle and high voltage ranges. The setup studied is a photovoltaic generator connected to an AC grid working in 230 Volts via an inverter. More over, we considered the possibility of multiple electrical energy sources as photovoltaic, wind systems in the same energy production system, which obliged an adaptive converter structure. We evaluated the losses in the various stages of a boost converter and point out the importance of the power MOSFET used as the commutation element. New transistors databases obtained from manufacturers show the nonlinear dependency between the resistance drain-source when passing, Rdson and the maximum rating voltage when the transistor is off, Vdsmax, for all transistor families. Thus nonlinear dependency induces a huge increase of losses with the voltage in the MOSFET, and as a direct consequence in the converter the more as Vdsmax is higher. In order to minimize losses of the converter we have designed and realized a new high efficiency version of a Step-Up structure based on a commutation element integrating a low Vdsmax voltage MOSFET and very low Rdson.

  9. Boosted objects: a probe of beyond the standard model physics

    DEFF Research Database (Denmark)

    Abdesselam, A.; Belyaev, A.; Kuutmann, E. B.;

    2011-01-01

    We present the report of the hadronic working group of the BOOST2010 workshop held at the University of Oxford in June 2010. The first part contains a review of the potential of hadronic decays of highly boosted particles as an aid for discovery at the LHC and a discussion of the status of tools ...

  10. Application ofBoost Inverter to Multi Input PV system

    Directory of Open Access Journals (Sweden)

    G.SHINYVIKRAM

    2014-11-01

    Full Text Available With the shortage of the energy and ever increasing of the oil price, research on the renewable and green energy sources, especially the solar arrays and the fuel cells, becomes more and more important. How to achieve high step- up and high efficiency DC/DC converters is the major consideration in the renewable power applications due to the low voltage of PV arrays and fuel cells. The conventional boost converters increase the harmonics rate and add an extra stage of power conversion. This paper proposes a boost dc-ac inverter that can invert and boost the output voltage in a single stage. In this paper the proposed boost dc-ac inverter is applied to the solar power panels and is simulated using Simulink. The output results of the boost inverter are worthy promising.

  11. Boosting low-mass hadronic resonances

    Science.gov (United States)

    Shimmin, Chase; Whiteson, Daniel

    2016-09-01

    Searches for new hadronic resonances typically focus on high-mass spectra due to overwhelming QCD backgrounds and detector trigger rates. We present a study of searches for relatively low-mass hadronic resonances at the LHC in the case that the resonance is boosted by recoiling against a well-measured high-pT probe such as a muon, photon or jet. The hadronic decay of the resonance is then reconstructed either as a single large-radius jet or as a resolved pair of standard narrow-radius jets, balanced in transverse momentum to the probe. We show that the existing 2015 LHC data set of p p collisions with ∫L d t =4 fb-1 should already have powerful sensitivity to a generic Z' model which couples only to quarks, for Z' masses ranging from 20 - 500 GeV /c2 .

  12. Very boosted Higgs in gluon fusion

    CERN Document Server

    Grojean, Christophe; Schlaffer, Matthias; Weiler, Andreas

    2014-01-01

    The Higgs production and decay rates offer a new way to probe new physics beyond the Standard Model. While dynamics aiming at alleviating the hierarchy problem generically predict deviations in the Higgs rates, the current experimental analyses cannot resolve the long- and short-distance contributions to the gluon fusion process and thus cannot access directly the coupling between the Higgs and the top quark. We investigate the production of a boosted Higgs in association with a high-transverse momentum jet as an alternative to the $t\\bar{t}h$ channel to pin down this crucial coupling. Presented first in the context of an effective field theory, our analysis is then applied to models of partial compositeness at the TeV scale and of natural supersymmetry.

  13. Opportunities to boost bioenergy in Lithuania

    Energy Technology Data Exchange (ETDEWEB)

    Silveira, Semida [International Secretariat, Swedish Energy Agency, Box 310, SE-631 04 Eskilstuna (Sweden); Andersson, Lars [Skogsvaardsstyrelsen Vaermland OErebro/Regional Forestry Board, Skogsenheten/Forest Department, P.O. Box 387, S-651 09 Karlstad (Sweden); Lebedys, Arvydas [Forest Economics Service, Forestry Department, Food and Agriculture Organization of UN, Viale delle Terme di Caracalla, 00100 Rome (Italy)

    2006-12-15

    Significant efforts have been made in Lithuania to enhance the utilization of bioenergy since the early 1990s. While opportunities are large and signs of development visible, bioenergy still needs technical, institutional and policy-related support for further development side by side with other industries. This paper discusses the existing bioenergy potential in Lithuanian forests, biofuels market formation in the region and possible roads to boost development. The retrofitting of heat plants, forest management and policies are reviewed as a way to identify opportunities to promote bioenergy in the country. It is shown that the interplay between national and regional forces can promote technological and managerial improvements in the forest industry while also enhancing the biomass supply and sustainability of bioenergy systems. (author) (author)

  14. Boosting low-mass hadronic resonances

    CERN Document Server

    Shimmin, Chase

    2016-01-01

    Searches for new hadronic resonances typically focus on high-mass spectra, due to overwhelming QCD backgrounds and detector trigger rates. We present a study of searches for relatively low-mass hadronic resonances at the LHC in the case that the resonance is boosted by recoiling against a well-measured high-$p_{\\textrm{T}}$ probe such as a muon, photon or jet. The hadronic decay of the resonance is then reconstructed either as a single large-radius jet or as a resolved pair of standard narrow-radius jets, balanced in transverse momentum to the probe. We show that the existing 2015 LHC dataset of $pp$ collisions with $\\int\\mathcal{L}dt = 4\\ \\mathrm{fb}^{-1}$ should already have powerful sensitivity to a generic $Z'$ model which couples only to quarks, for $Z'$ masses ranging from 20-500 GeV/c$^2$.

  15. Giving top quark effective operators a boost

    CERN Document Server

    Englert, Christoph; Moore, Liam; Russell, Michael

    2016-01-01

    We investigate the prospects to systematically improve generic effective field theory-based searches for new physics in the top sector during LHC run 2 as well as the high luminosity phase. In particular, we assess the benefits of high momentum transfer final states on top EFT-fit as a function of systematic uncertainties in comparison with sensitivity expected from fully-resolved analyses focusing on $t\\bar t$ production. We find that constraints are typically driven by fully-resolved selections, while boosted top quarks can serve to break degeneracies in the global fit. This demystifies and clarifies the importance of high momentum transfer final states for global fits to new interactions in the top sector from direct measurements.

  16. Very boosted Higgs in gluon fusion

    Energy Technology Data Exchange (ETDEWEB)

    Grojean, C. [ICREA at IFAE, Universitat Autónoma de Barcelona,E-08193 Bellaterra (Spain); Salvioni, E. [Department of Physics, University of California,Davis, CA 95616 (United States); Theory Division, Physics Department, CERN,CH-1211 Geneva 23 (Switzerland); Dipartimento di Fisica e Astronomia, Università di Padova and INFN, Sezione di Padova,Via Marzolo 8, I-35131 Padova (Italy); Schlaffer, M. [DESY,Notkestrasse 85, D-22607 Hamburg (Germany); Weiler, A. [Theory Division, Physics Department, CERN,CH-1211 Geneva 23 (Switzerland); DESY,Notkestrasse 85, D-22607 Hamburg (Germany)

    2014-05-06

    The Higgs production and decay rates offer a new way to probe new physics beyond the Standard Model. While dynamics aiming at alleviating the hierarchy problem generically predict deviations in the Higgs rates, the current experimental analyses cannot resolve the long- and short-distance contributions to the gluon fusion process and thus cannot access directly the coupling between the Higgs and the top quark. We investigate the production of a boosted Higgs in association with a high-transverse momentum jet as an alternative to the tt-macronh channel to pin down this crucial coupling. Presented first in the context of an effective field theory, our analysis is then applied to models of partial compositeness at the TeV scale and of natural supersymmetry.

  17. Boosting jet power in black hole spacetimes

    CERN Document Server

    Neilsen, David; Palenzuela, Carlos; Hirschmann, Eric W; Liebling, Steven L; Motl, Patrick M; Garret, T

    2010-01-01

    The extraction of rotational energy from a spinning black hole via the Blandford-Znajek mechanism has long been understood as an important component in models to explain energetic jets from compact astrophysical sources. Here we show more generally that the kinetic energy of the black hole, both rotational and translational, can be tapped, thereby producing even more luminous jets powered by the interaction of the black hole with its surrounding plasma. We study the resulting Poynting jet that arises from single boosted black holes and binary black hole systems. In the latter case, we find that increasing the orbital angular momenta of the system and/or the spins of the individual black holes results in an enhanced Poynting flux.

  18. Boosting jet power in black hole spacetimes

    Science.gov (United States)

    Neilsen, David; Lehner, Luis; Palenzuela, Carlos; Hirschmann, Eric W.; Liebling, Steven L.; Motl, Patrick M.; Garrett, Travis

    2011-01-01

    The extraction of rotational energy from a spinning black hole via the Blandford–Znajek mechanism has long been understood as an important component in models to explain energetic jets from compact astrophysical sources. Here we show more generally that the kinetic energy of the black hole, both rotational and translational, can be tapped, thereby producing even more luminous jets powered by the interaction of the black hole with its surrounding plasma. We study the resulting Poynting jet that arises from single boosted black holes and binary black hole systems. In the latter case, we find that increasing the orbital angular momenta of the system and/or the spins of the individual black holes results in an enhanced Poynting flux. PMID:21768341

  19. Boosting jet power in black hole spacetimes.

    Science.gov (United States)

    Neilsen, David; Lehner, Luis; Palenzuela, Carlos; Hirschmann, Eric W; Liebling, Steven L; Motl, Patrick M; Garrett, Travis

    2011-08-01

    The extraction of rotational energy from a spinning black hole via the Blandford-Znajek mechanism has long been understood as an important component in models to explain energetic jets from compact astrophysical sources. Here we show more generally that the kinetic energy of the black hole, both rotational and translational, can be tapped, thereby producing even more luminous jets powered by the interaction of the black hole with its surrounding plasma. We study the resulting Poynting jet that arises from single boosted black holes and binary black hole systems. In the latter case, we find that increasing the orbital angular momenta of the system and/or the spins of the individual black holes results in an enhanced Poynting flux.

  20. Very boosted Higgs in gluon fusion

    Energy Technology Data Exchange (ETDEWEB)

    Grojean, C. [Univ. Autonoma de Barcelona, Bellaterra (Spain). ICREA at IFAE; Salvioni, E. [California Univ., Davis, CA (United States). Dept. of Physics; European Organization for Nuclear Research (CERN), Geneva (Switzerland); Padova Univ. (Italy). Dipt. di Fisica e Astronomica; INFN, Sezione di Padova (Italy); Schlaffer, M. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Weiler, A. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2013-12-15

    The Higgs production and decay rates offer a new way to probe new physics beyond the Standard Model. While dynamics aiming at alleviating the hierarchy problem generically predict deviations in the Higgs rates, the current experimental analyses cannot resolve the long- and short-distance contributions to the gluon fusion process and thus cannot access directly the coupling between the Higgs and the top quark. We investigate the production of a boosted Higgs in association with a high-transverse momentum jet as an alternative to the t anti th channel to pin down this crucial coupling. Presented rst in the context of an effective field theory, our analysis is then applied to models of partial compositeness at the TeV scale and of natural supersymmetry.

  1. Boosted W/Z Tagging at ATLAS

    CERN Document Server

    Dattagupta, Aparajita; The ATLAS collaboration

    2016-01-01

    A detailed study of the techniques for identifying boosted hadronically decaying W or Z bosons is presented. The best performing algorithm for reconstructing, grooming and tagging bosonic jets as seen in studies using 8 TeV data and simulation is validated for W bosons with a wide range of transverse momenta using 13 TeV data and MC simulations. The same is studied for Z bosons in 13 TeV MC simulation. Improvement in tagger performance using detector tracking information is also studied. In addition, given that a hadronic jet has been identified as resulting from the hadronic decay of a W or Z, a technique is developed to discriminate between W and Z bosons using 8 TeV data. The alternative of using variable-R jets for capturing the hadronic decay products compared to standard techniques is also discussed.

  2. Boosted jets in searches for new physics

    Energy Technology Data Exchange (ETDEWEB)

    Spannowsky, Michael [Institute for Particle Physics Phenomenology, Department of Physics, Durham University (United Kingdom)

    2012-07-01

    Jets are collimated sprays of hadrons. They are the most complex and least understood, but also the most frequently observed objects at the LHC. Almost all theoretical extensions of the standard model predict heavy TeV scale resonances which, to explain electroweak symmetry breaking, have to couple to electroweak scale resonances, e.g. top quarks or electroweak gauge bosons. Therefore, boosted electroweak-scale resonances with large branching ratios into jets is a highly probable and enthusiastic scenario in many processes probing new physics. The resonances' collimated hadronic decay products can easily blend with the cornucopia of jets from hard relative light QCD states. Here, jet substructure methods can help to disentangle the sought-after signal from the backgrounds. In this talk we classify, motivate and discuss scenarios where jet substructure methods can be beneficial for new physics searches at the LHC.

  3. On the maximum regulation range in boost and buck-boost converters

    Science.gov (United States)

    Ninomiya, T.; Harada, K.; Nakahara, M.

    Two types of instability conditions in boost and buck-boost converters with a feedback loop are analyzed by means of the steady-state characteristic and dynamic small-signal modeling. Type I instability involves a drastic voltage drop, and in Type II instability, a limit-cycle oscillation arises and the output voltage oscillates at low frequencies. The maximum regulation range is derived analytically for the load variation and verified experimentally. For high feedback gain, it is determined by the Type II instability condition, whereas for low feedback gain, it is determined by the Type I instability condition. Type II instability can be suppressed by decreasing the reactor inductance or by increasing the capacitance of a smoothing capacitor. However, Type I instability is found to be independent of these values.

  4. Glucose starvation boosts Entamoeba histolytica virulence.

    Directory of Open Access Journals (Sweden)

    Ayala Tovy

    2011-08-01

    Full Text Available The unicellular parasite, Entamoeba histolytica, is exposed to numerous adverse conditions, such as nutrient deprivation, during its life cycle stages in the human host. In the present study, we examined whether the parasite virulence could be influenced by glucose starvation (GS. The migratory behaviour of the parasite and its capability to kill mammalian cells and to lyse erythrocytes is strongly enhanced following GS. In order to gain insights into the mechanism underlying the GS boosting effects on virulence, we analyzed differences in protein expression levels in control and glucose-starved trophozoites, by quantitative proteomic analysis. We observed that upstream regulatory element 3-binding protein (URE3-BP, a transcription factor that modulates E.histolytica virulence, and the lysine-rich protein 1 (KRiP1 which is induced during liver abscess development, are upregulated by GS. We also analyzed E. histolytica membrane fractions and noticed that the Gal/GalNAc lectin light subunit LgL1 is up-regulated by GS. Surprisingly, amoebapore A (Ap-A and cysteine proteinase A5 (CP-A5, two important E. histolytica virulence factors, were strongly down-regulated by GS. While the boosting effect of GS on E. histolytica virulence was conserved in strains silenced for Ap-A and CP-A5, it was lost in LgL1 and in KRiP1 down-regulated strains. These data emphasize the unexpected role of GS in the modulation of E.histolytica virulence and the involvement of KRiP1 and Lgl1 in this phenomenon.

  5. The attentional boost effect and context memory.

    Science.gov (United States)

    Mulligan, Neil W; Smith, S Adam; Spataro, Pietro

    2016-04-01

    Stimuli co-occurring with targets in a detection task are better remembered than stimuli co-occurring with distractors-the attentional boost effect (ABE). The ABE is of interest because it is an exception to the usual finding that divided attention during encoding impairs memory. The effect has been demonstrated in tests of item memory but it is unclear if context memory is likewise affected. Some accounts suggest enhanced perceptual encoding or associative binding, predicting an ABE on context memory, whereas other evidence suggests a more abstract, amodal basis of the effect. In Experiment 1, context memory was assessed in terms of an intramodal perceptual detail, the font and color of the study word. Experiment 2 examined context memory cross-modally, assessing memory for the modality (visual or auditory) of the study word. Experiments 3 and 4 assessed context memory with list discrimination, in which 2 study lists are presented and participants must later remember which list (if either) a test word came from. In all experiments, item (recognition) memory was also assessed and consistently displayed a robust ABE. In contrast, the attentional-boost manipulation did not enhance context memory, whether defined in terms of visual details, study modality, or list membership. There was some evidence that the mode of responding on the detection task (motoric response as opposed to covert counting of targets) may impact context memory but there was no evidence of an effect of target detection, per se. In sum, the ABE did not occur in context memory with verbal materials. (PsycINFO Database Record PMID:26348201

  6. Inductor and TSV Design of 20-V Boost Converter for Low Power 3D Solid State Drive with NAND Flash Memories

    Science.gov (United States)

    Yasufuku, Tadashi; Ishida, Koichi; Miyamoto, Shinji; Nakai, Hiroto; Takamiya, Makoto; Sakurai, Takayasu; Takeuchi, Ken

    Two essential technologies for a 3D Solid State Drive (3D-SSD) with a boost converter are presented in this paper. The first topic is the spiral inductor design which determines the performance of the boost converter, and the second is the effect of TSV's on the boost converter. These techniques are very important in achieving a 3D-SSD with a boost converter. In the design of the inductor, the on-board inductor from 250nH to 320nH is the best design feature that meets all requirements, including high output voltage above 20V, fast rise time, low energy consumption, and area smaller than 25mm2. The use of a boost converter with the proposed inductor leads to a reduction of the energy consumption during the write operation of the proposed 1.8-V 3D-SSD by 68% compared with the conventional 3.3-V 3D-SSD with the charge pump. The feasibility of 3D-SSD's with Through Silicon Vias (TSV's) connections is also discussed. In order to maintain the advantages of the boost converter over the charge pump, the reduction of the parasitic resistance of TSV's is very important.

  7. Older Cancer Patients’ User Experiences With Web-Based Health Information Tools: A Think-Aloud Study

    Science.gov (United States)

    Romijn, Geke; Smets, Ellen M A; Loos, Eugene F; Kunneman, Marleen; van Weert, Julia C M

    2016-01-01

    Background Health information is increasingly presented on the Internet. Several Web design guidelines for older Web users have been proposed; however, these guidelines are often not applied in website development. Furthermore, although we know that older individuals use the Internet to search for health information, we lack knowledge on how they use and evaluate Web-based health information. Objective This study evaluates user experiences with existing Web-based health information tools among older (≥ 65 years) cancer patients and survivors and their partners. The aim was to gain insight into usability issues and the perceived usefulness of cancer-related Web-based health information tools. Methods We conducted video-recorded think-aloud observations for 7 Web-based health information tools, specifically 3 websites providing cancer-related information, 3 Web-based question prompt lists (QPLs), and 1 values clarification tool, with colorectal cancer patients or survivors (n=15) and their partners (n=8) (median age: 73; interquartile range 70-79). Participants were asked to think aloud while performing search, evaluation, and application tasks using the Web-based health information tools. Results Overall, participants perceived Web-based health information tools as highly useful and indicated a willingness to use such tools. However, they experienced problems in terms of usability and perceived usefulness due to difficulties in using navigational elements, shortcomings in the layout, a lack of instructions on how to use the tools, difficulties with comprehensibility, and a large amount of variety in terms of the preferred amount of information. Although participants frequently commented that it was easy for them to find requested information, we observed that the large majority of the participants were not able to find it. Conclusions Overall, older cancer patients appreciate and are able to use cancer information websites. However, this study shows the importance

  8. Photovoltaic Simplified Boost Z Source Inverter for Ac Module Applications

    Directory of Open Access Journals (Sweden)

    J. Sam Alaric

    2014-08-01

    Full Text Available This study mainly proposed PV z source boost inverter used to boundary grid or ac module applications. Separate types of converter used for solar system due to its current lagging, here capacitor multiplier based boost converter introduced for maintain the current lagging and voltage gain. Here, the switched inductor z source inverter implemented for grid interface. Proposed z source inverter is controlled by pulse width modulation. A simplified capacitor multiplier controlled by continuous conduction mode, A detailed topology analysis and a generalized discussion are given. The multiplier boost converter has the merits of maintain voltage level and reducing cost and current lagging. Simulation results are implemented and analysis MATLAB software.

  9. Remote Sensing Data Binary Classification Using Boosting with Simple Classifiers

    Directory of Open Access Journals (Sweden)

    Nowakowski Artur

    2015-10-01

    Full Text Available Boosting is a classification method which has been proven useful in non-satellite image processing while it is still new to satellite remote sensing. It is a meta-algorithm, which builds a strong classifier from many weak ones in iterative way. We adapt the AdaBoost.M1 boosting algorithm in a new land cover classification scenario based on utilization of very simple threshold classifiers employing spectral and contextual information. Thresholds for the classifiers are automatically calculated adaptively to data statistics.

  10. Optimized MPPT algorithm for boost converters taking into account the environmental variables

    Science.gov (United States)

    Petit, Pierre; Sawicki, Jean-Paul; Saint-Eve, Frédéric; Maufay, Fabrice; Aillerie, Michel

    2016-07-01

    This paper presents a study on the specific behavior of the Boost DC-DC converters generally used for powering conversion of PV panels connected to a HVDC (High Voltage Direct Current) Bus. It follows some works pointing out that converter MPPT (Maximum Power Point Tracker) is severely perturbed by output voltage variations due to physical dependency of parameters as the input voltage, the output voltage and the duty cycle of the PWM switching control of the MPPT. As a direct consequence many converters connected together on a same load perturb each other because of the output voltage variations induced by fluctuations on the HVDC bus essentially due to a not insignificant bus impedance. In this paper we show that it is possible to include an internal computed variable in charge to compensate local and external variations to take into account the environment variables.

  11. On Theory and Practice in Reading Aloud from Character of Phonetics%从语音性质谈朗读的理论与实践

    Institute of Scientific and Technical Information of China (English)

    赵介平

    2012-01-01

    朗读学是关于朗读的专门学说,在阅读学、语文教学论的视野下研究朗读非常重要。从语言角度看,朗读把文字语言转化为有声语言是语音的外显、语音的"复活",因此对语音性质的研究,是朗读理论与朗读实践中的重要内容。语音的社会性质是语音的本质属性,其内涵不仅在于字符词语语音形式的表"义",更在于其表"意",更在于有声语流的语音形式如何"传情达意",对朗读起决定作用。朗读者遵循朗读的科学规律与艺术规律,可以更好地实现语言的社会功能。%The study of reading aloud is a specialized theory.It is important to carry on researches on reading aloud from reading education and from Chinese teaching perspectives.Viewing from the language,reading aloud converts the written language into verbal language,and is the explicit behavior of the phonetics as well as the revival of the phonetics.Therefore,the study on the nature of phonetics is an important part in the reading aloud theory and practice.The social quality of phonetics is its essence.Not only does the connotation of the social quality of phonetics lie in the characters and words and forms of phonetics but also the meaning of it.In fact,people pay more attention to the expression of one's idea through intonation of the verbal language.The reader following the scientific law and artistic rules of reading aloud can better realize the social function of the language.

  12. A boost for the ISOLDE beams

    CERN Multimedia

    Corinne Pralavorio

    2015-01-01

    The first HIE-ISOLDE cryomodule was commissioned at the end of October. The radioactive ion beams can now be accelerated to 4.3 MeV per nucleon.   The ISOLDE beamline that supplies the Miniball array. The first HIE-ISOLDE cryomodule can be seen in the background, in its light-grey cryostat. ISOLDE is getting an energy boost. The first cryomodule of the new superconducting linear accelerator HIE-ISOLDE (High Intensity and Energy ISOLDE), located downstream of the REX-ISOLDE accelerator, increases the energy of the radioactive ion beams from 3 to 4.3 MeV per nucleon. It supplies the Miniball array, where an experiment using radioactive zinc ions (see box) began at the end of October. This is the first stage in the commissioning of HIE-ISOLDE. The facility will ultimately be equipped with four cryomodules that will accelerate the beams to 10 MeV per nucleon. Each cryomodule has five accelerating cavities and a solenoid, which focuses the beam. All of these components are superconducting. This first ...

  13. Exploiting tRNAs to Boost Virulence.

    Science.gov (United States)

    Albers, Suki; Czech, Andreas

    2016-01-01

    Transfer RNAs (tRNAs) are powerful small RNA entities that are used to translate nucleotide language of genes into the amino acid language of proteins. Their near-uniform length and tertiary structure as well as their high nucleotide similarity and post-transcriptional modifications have made it difficult to characterize individual species quantitatively. However, due to the central role of the tRNA pool in protein biosynthesis as well as newly emerging roles played by tRNAs, their quantitative assessment yields important information, particularly relevant for virus research. Viruses which depend on the host protein expression machinery have evolved various strategies to optimize tRNA usage-either by adapting to the host codon usage or encoding their own tRNAs. Additionally, several viruses bear tRNA-like elements (TLE) in the 5'- and 3'-UTR of their mRNAs. There are different hypotheses concerning the manner in which such structures boost viral protein expression. Furthermore, retroviruses use special tRNAs for packaging and initiating reverse transcription of their genetic material. Since there is a strong specificity of different viruses towards certain tRNAs, different strategies for recruitment are employed. Interestingly, modifications on tRNAs strongly impact their functionality in viruses. Here, we review those intersection points between virus and tRNA research and describe methods for assessing the tRNA pool in terms of concentration, aminoacylation and modification. PMID:26797637

  14. Exploiting tRNAs to Boost Virulence

    Directory of Open Access Journals (Sweden)

    Suki Albers

    2016-01-01

    Full Text Available Transfer RNAs (tRNAs are powerful small RNA entities that are used to translate nucleotide language of genes into the amino acid language of proteins. Their near-uniform length and tertiary structure as well as their high nucleotide similarity and post-transcriptional modifications have made it difficult to characterize individual species quantitatively. However, due to the central role of the tRNA pool in protein biosynthesis as well as newly emerging roles played by tRNAs, their quantitative assessment yields important information, particularly relevant for virus research. Viruses which depend on the host protein expression machinery have evolved various strategies to optimize tRNA usage—either by adapting to the host codon usage or encoding their own tRNAs. Additionally, several viruses bear tRNA-like elements (TLE in the 5′- and 3′-UTR of their mRNAs. There are different hypotheses concerning the manner in which such structures boost viral protein expression. Furthermore, retroviruses use special tRNAs for packaging and initiating reverse transcription of their genetic material. Since there is a strong specificity of different viruses towards certain tRNAs, different strategies for recruitment are employed. Interestingly, modifications on tRNAs strongly impact their functionality in viruses. Here, we review those intersection points between virus and tRNA research and describe methods for assessing the tRNA pool in terms of concentration, aminoacylation and modification.

  15. Exploiting tRNAs to Boost Virulence

    Science.gov (United States)

    Albers, Suki; Czech, Andreas

    2016-01-01

    Transfer RNAs (tRNAs) are powerful small RNA entities that are used to translate nucleotide language of genes into the amino acid language of proteins. Their near-uniform length and tertiary structure as well as their high nucleotide similarity and post-transcriptional modifications have made it difficult to characterize individual species quantitatively. However, due to the central role of the tRNA pool in protein biosynthesis as well as newly emerging roles played by tRNAs, their quantitative assessment yields important information, particularly relevant for virus research. Viruses which depend on the host protein expression machinery have evolved various strategies to optimize tRNA usage—either by adapting to the host codon usage or encoding their own tRNAs. Additionally, several viruses bear tRNA-like elements (TLE) in the 5′- and 3′-UTR of their mRNAs. There are different hypotheses concerning the manner in which such structures boost viral protein expression. Furthermore, retroviruses use special tRNAs for packaging and initiating reverse transcription of their genetic material. Since there is a strong specificity of different viruses towards certain tRNAs, different strategies for recruitment are employed. Interestingly, modifications on tRNAs strongly impact their functionality in viruses. Here, we review those intersection points between virus and tRNA research and describe methods for assessing the tRNA pool in terms of concentration, aminoacylation and modification. PMID:26797637

  16. Gendered Connections

    DEFF Research Database (Denmark)

    Jensen, Steffen Bo

    2009-01-01

    This article explores the gendered nature of urban politics in Cape Town by focusing on a group of female, township politicians. Employing the Deleuzian concept of `wild connectivity', it argues that these politically entrepreneurial women were able to negotiate a highly volatile urban landscape ...... of connectivity might endure, as Capetonian politics assumes a post-apartheid structure....

  17. Severe Obesity May Boost Infection Risk After Heart Surgery

    Science.gov (United States)

    ... https://medlineplus.gov/news/fullstory_159143.html Severe Obesity May Boost Infection Risk After Heart Surgery Excess ... new study suggests. The researchers found that severe obesity was linked to much higher odds of developing ...

  18. Testosterone Therapy May Boost Older Men's Sex Lives

    Science.gov (United States)

    ... 159622.html Testosterone Therapy May Boost Older Men's Sex Lives Gel hormone treatment led to improved libido ... experienced a moderate but significant improvement in their sex drive, sexual activity and erectile function compared to ...

  19. Insurance Mandates Boost U.S. Autism Diagnoses

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_159812.html Insurance Mandates Boost U.S. Autism Diagnoses Early treatment provides ... the Penn researchers analyzed inpatient and outpatient health insurance claims from 2008 through 2012 for more than ...

  20. Severe Obesity May Boost Infection Risk After Heart Surgery

    Science.gov (United States)

    ... nih.gov/medlineplus/news/fullstory_159143.html Severe Obesity May Boost Infection Risk After Heart Surgery Excess ... new study suggests. The researchers found that severe obesity was linked to much higher odds of developing ...

  1. Zika's Delivery Via Mosquito Bite May Boost Its Effect

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_159484.html Zika's Delivery Via Mosquito Bite May Boost Its Effect ... The inflammation caused by a mosquito bite helps Zika and other viruses spread through the body more ...

  2. Beijing to Boost Gas Consumption for Green Games

    Institute of Scientific and Technical Information of China (English)

    Zhang Jian

    2002-01-01

    @@ To implement the "Green Olympic"strategy proposed in "Plan for Beijing Olympic Games,"Beijing Gas Group Company will boost its annual gas supply to 4 billion cubic meters by 2005 and 6 billion cubic meters by 2010.

  3. Superconducting Electric Boost Pump for Nuclear Thermal Propulsion Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A submersible, superconducting electric boost pump sized to meet the needs of future Nuclear Thermal Propulsion systems in the 25,000 lbf thrust range is proposed....

  4. Exposure / Ritual Prevention Therapy Boosts Antidepressant Treatment of OCD

    Science.gov (United States)

    ... NIMH (99 items) Exposure / Ritual Prevention Therapy Boosts Antidepressant Treatment of OCD CBT Trumps Antipsychotic for Augmentation, ... Update A form of behavioral therapy can augment antidepressant treatment of obsessive compulsive disorder (OCD) better than ...

  5. Boosting-like Deep Learning For Pedestrian Detection

    OpenAIRE

    Wang, Lei; Zhang, Baochang

    2015-01-01

    This paper proposes boosting-like deep learning (BDL) framework for pedestrian detection. Due to overtraining on the limited training samples, overfitting is a major problem of deep learning. We incorporate a boosting-like technique into deep learning to weigh the training samples, and thus prevent overtraining in the iterative process. We theoretically give the details of derivation of our algorithm, and report the experimental results on open data sets showing that BDL achieves a better sta...

  6. Face Alignment using Boosted Appeareance Model (Discriminative Appearance Model)

    OpenAIRE

    Muddamsetty, Satya Mahesh

    2009-01-01

    This thesis explores decriminative face alignment using Boosted Appearance Model (BAM). In this method face alignment is done by maximizing the score of the trained two classifier which learns both correct and incorrect alignment and is able to distinguish correct and incorrect alignment so that the correct alignment gets maximum positve score. During the training stage we trained Point Distribution Model (PDM) which acts as shape model and a boosting based classifier based on Haar like Recta...

  7. Complexified boost invariance and holographic heavy ion collisions

    OpenAIRE

    Gubser, Steven; van der Schee, Wilke

    2014-01-01

    At strong coupling holographic studies have shown that heavy ion collisions do not obey normal boost invariance. Here we study a modified boost invariance through a complex shift in time, and show that this leads to surprisingly good agreement with numerical holographic computations. When including perturbations the agreement becomes even better, both in the hydrodynamic and the far-from-equilibrium regime. One of the main advantages is an analytic formulation of the stress-energy tensor of t...

  8. Positive Semidefinite Metric Learning Using Boosting-like Algorithms

    OpenAIRE

    Shen, Chunhua; Kim, Junae; Wang, Lei; Hengel, Anton van den

    2011-01-01

    The success of many machine learning and pattern recognition methods relies heavily upon the identification of an appropriate distance metric on the input data. It is often beneficial to learn such a metric from the input training data, instead of using a default one such as the Euclidean distance. In this work, we propose a boosting-based technique, termed BoostMetric, for learning a quadratic Mahalanobis distance metric. Learning a valid Mahalanobis distance metric requires enforcing the co...

  9. Three Phase High Power Quality Two- Stage Boost Rectifier

    OpenAIRE

    P.NAMMALVAR; S. ANNAPOORANI

    2012-01-01

    Three-phase two-stage boost rectifier with sinusoidal input current are presented and a novel topology with two active power devices is proposed. These contain a capacitor for pumping action in DC circuit. This gives twostage boost operation to obtain higher DC output voltage. The rectifier can be operated in the switch mode forpumping action and for forcing the input current to follow its sinusoidal reference independent of the working conditions. The results of the proposed rectifier are co...

  10. Boosting the partial least square algorithm for regression modelling

    Institute of Scientific and Technical Information of China (English)

    Ling YU; Tiejun WU

    2006-01-01

    Boosting algorithms are a class of general methods used to improve the general performance of regression analysis. The main idea is to maintain a distribution over the train set. In order to use the given distribution directly,a modified PLS algorithm is proposed and used as the base learner to deal with the nonlinear multivariate regression problems. Experiments on gasoline octane number prediction demonstrate that boosting the modified PLS algorithm has better general performance over the PLS algorithm.

  11. Searches with Boosted Objects at ATLAS and CMS

    CERN Document Server

    Behr, K; The ATLAS collaboration

    2014-01-01

    This talk presents an overview of searches for new physics in boosted final states conducted by the ATLAS and CMS experiments during Run-I of the LHC. An emphasis is put on techniques for the reconstruction and identification of both hadronic and leptonic decays of objects with large transverse momenta: Various substructure and grooming techniques as well as modified lepton isolation criteria are reviewed and their use in the most common algorithms for boosted top and boson tagging is discussed.

  12. About Connections

    Directory of Open Access Journals (Sweden)

    Kathleen S Rockland

    2015-05-01

    Full Text Available Despite the attention attracted by connectomics, one can lose sight of the very real questions concerning What are connections? In the neuroimaging community, structural connectivity is ground truth and underlying constraint on functional or effective connectivity. It is referenced to underlying anatomy; but, as increasingly remarked, there is a large gap between the wealth of human brain mapping and the relatively scant data on actual anatomical connectivity. Moreover, connections have typically been discussed as pairwise, point x projecting to point y (or: to points y and z, or more recently, in graph theoretical terms, as nodes or regions and the interconnecting edges. This is a convenient shorthand, but tends not to capture the richness and nuance of basic anatomical properties as identified in the classic tradition of tracer studies. The present short review accordingly revisits connectional weights, heterogeneity, reciprocity, topography, and hierarchical organization, drawing on concrete examples. The emphasis is on presynaptic long-distance connections, motivated by the intention to probe current assumptions and promote discussions about further progress and synthesis.

  13. AdaBoost分类问题的理论推导%Theory deduction of AdaBoost classification

    Institute of Scientific and Technical Information of China (English)

    严超; 王元庆; 李久雪; 张兆扬

    2011-01-01

    为解决AdaBoost算法在二分类问题及多分类问题上缺乏共同的理论基础,算法系列的系统性难以得到理论诠释这一问题,首先,从算法思想的层面对AdaBoost算法与最优贝叶斯推理的关系进行了探讨;然后对AdaBoost算法的训练流程及相关参量进行了定量分析;最后从基本不等式定理入手,重点推导了AdaBoost算法由二分类问题向多分类问题延展的理论依据,探讨了AdaBoost算法的本质.总结并证明了AdaBoost算法的2条理论基础:当非负数之和是一个定值时,其差值越大则其乘积越小;非负数的算术平均数大于等于它们的几何平均数.并且分别就二分类问题和多分类问题对AdaBoost算法的应用提出了优化策略.%AdaBoost two-classification and AdaBoost multi-classification lack mutual theory principals, so the unity of AdaBoost algorithm could not be represented theorically. To solve this problem , firstly, the connection of AdaBoost algorithm and Bayes Inference is probed; secondly, the training process and relative parameters of AdaBoost algorithm are analyzed quantitatively; thirdly, with fundamental inequality principals, the extension process of AdaBoost algorithm from two-classification application to multi-classification application is reasoned. Two intrinsic theories are summarized and proved: if the sum of some non-negative numbers is fixed, their product will become smaller when their values difference become greater; arithmetic average of some non-negative numbers is greater than their geometric average. In addition, some improvements to two-classification and multi-classification applications are suggested.

  14. HR Connect

    Data.gov (United States)

    US Agency for International Development — HR Connect is the USAID HR personnel system which allows HR professionals to process HR actions related to employee's personal and position information. This system...

  15. FONÉTICA APLICADA: DIAGNOSTICO Y TRATAMIENTO DE DEFICIENCIAS EN LA LECTURA EN VOZ ALTA APPLIED PHONETICS: DIAGNOSIS AND TREATMENT OF DEFICIENCIES IN READING ALOUD

    Directory of Open Access Journals (Sweden)

    HUMBERTO VALDIVIESO

    2007-01-01

    Full Text Available Considerando que la lectura en voz alta es una actividad culturalmente muy relevante y frente a ella la comunidad parece adoptar la actitud más crítica, este trabajo presenta los principales resultados de un diagnóstico y un tratamiento fonético de deficiencias en la lectura en voz alta. Para realizar el diagnóstico se utilizan 30 estudiantes de primer año de Pedagogía en Español y para el tratamiento fonético, 12 de ellos, 6 para la muestra experimental y 6 para el grupo control. Las principales tendencias que se perfilan de este estudio muestran que los estudiantes presentan serias deficiencias en la calidad de la lectura oral, pero también que mediante un tratamiento fonético adecuado, que incluye evaluación o diagnóstico de la expresión oral, actividades de lectura en voz alta y ejercicios fonéticos pertinentes, es posible corregir y desarrollar este aspecto de la lengua maternaConsidering that reading aloud is a very relevant activity from a cultural point of view, this article presents the main results from a phonetic diagnosis and a phonetic treatment on reading aloud disabilities. The diagnosis was applied to 30 first-year university students of Spanish as a mother tongue. The treatment was performed with a selection of 12 of these students: 6 for the experimental sample, and the other 6 for the control group. The main trends outlined from the study reveal the students have serious difficulties in managing the quality of their oral reading. However, the results also show that it is possible to correct and improve this aspect of the mother tongue competence through proper phonetic treatment -in this case including oral expression testing, reading aloud activities and related phonetic drills

  16. Intake Manifold Boosting of Turbocharged Spark-Ignited Engines

    Directory of Open Access Journals (Sweden)

    Lino Guzzella

    2013-03-01

    Full Text Available Downsizing and turbocharging is a widely used approach to reduce the fuel consumption of spark ignited engines while retaining the maximum power output. However, a substantial loss in drivability must be expected due to the occurrence of the so-called turbo lag. The turbo lag results from the additional inertia that the turbocharger adds to the system. Supplying air by an additional valve, the boost valve, to the intake manifold can be used to overcome the turbo lag. This turbo lag compensationmethod is referred to as intakemanifold boosting. The aims of this study are to show the effectiveness of intake manifold boosting on a turbocharged spark-ignited engine and to show that intake manifold boosting can be used as an enabler of strong downsizing. Guidelines for the dimensioning of the boost valve are given and a control strategy is presented. The trade-off between additional fuel consumption and the consumption of pressurized air during the turbo lag compensation is discussed. For a load step at 2000 rpm the rise time can be reduced from 2.8 s to 124ms, requiring 11.8 g of pressurized air. The transient performance is verified experimentally by means of load steps at various engine speeds to various engine loads.

  17. The impact of subsea boosting on deepwater field development

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, O.J.S.; Camargo, R.M.T.; Paulo, C.A.S. [Petrobras, Rio de Janeiro (Brazil)

    1996-12-31

    This paper describes the impact that the use of a subsea boosting system will have on the development of a deepwater field. The analysis covers the technology demands and constraints encountered on screening studies executed for the fields of Marlim, Albacora and Barracuda, as well as an overview of the economic benefits encountered. The paper focuses on the technological demands and constraints identified as well as some considerations about possible alternatives. The demands and constraints identified in the study will provide the industry with some more input to guide the development of the subsea boosting technology, as well as a better understanding of how to apply this new tool on the development of deepwater prospects. The results of the screening study are showing that the subsea boosting systems are a valuable tool to reduce the costs of deepwater developments. The cost cutting possibilities through an integration between the conventional subsea hardware and the subsea boosting systems and the combination of boosting systems are promising alternatives. The encouraging economic results found, as well as the demands and constraints raised in the paper will be of use for those trying to apply these technologies in various areas of the world.

  18. Incorporating pathway information into boosting estimation of high-dimensional risk prediction models

    Directory of Open Access Journals (Sweden)

    Binder Harald

    2009-01-01

    Full Text Available Abstract Background There are several techniques for fitting risk prediction models to high-dimensional data, arising from microarrays. However, the biological knowledge about relations between genes is only rarely taken into account. One recent approach incorporates pathway information, available, e.g., from the KEGG database, by augmenting the penalty term in Lasso estimation for continuous response models. Results As an alternative, we extend componentwise likelihood-based boosting techniques for incorporating pathway information into a larger number of model classes, such as generalized linear models and the Cox proportional hazards model for time-to-event data. In contrast to Lasso-like approaches, no further assumptions for explicitly specifying the penalty structure are needed, as pathway information is incorporated by adapting the penalties for single microarray features in the course of the boosting steps. This is shown to result in improved prediction performance when the coefficients of connected genes have opposite sign. The properties of the fitted models resulting from this approach are then investigated in two application examples with microarray survival data. Conclusion The proposed approach results not only in improved prediction performance but also in structurally different model fits. Incorporating pathway information in the suggested way is therefore seen to be beneficial in several ways.

  19. A Low Cost Single-Switch Bridgeless Boost PFC Converter

    Directory of Open Access Journals (Sweden)

    Younghoon Cho

    2014-03-01

    Full Text Available This paper proposes the single-switch bridgeless boost power factor correction (PFC converter to achieve high efficiency in low cost. The proposed converter utilizes only one active switching device for PFC operation as well as expecting higher efficiency than typical boost PFC converters. On the other hand, the implementation cost is less than traditional bridgeless boost PFC converters, in where two active switching deivces are necessary. The operational principle, the modeling, and the control scheme of the proposed converter are discussed in detail. In order to verify the operation of the proposed converter, a 500W switching model is built in PSIM software package. The simulation results show that the proposed converter perfectly achieves PFC operation with only a single active switch.

  20. Power boost of gas turbines by inlet air cooling

    Energy Technology Data Exchange (ETDEWEB)

    White, C.; Raghu, S. [State Univ. of New York, Stony Brook, NY (United States). Dept. of Mechanical Engineering; Giannotti, G.; Giannotti, H. [Giannotti Associates, Bellport, NY (United States)

    1996-12-31

    The design of a power boost system for an existing gas turbine unit using a direct spray evaporative spray cooling method is described in this paper. Experiments were conducted to determine the extent of cooling possible by this method, droplet size requirements and spray water requirements. Although up to 4.9% of power boost is theoretically possible at the design conditions of 32.2 C (90 F) and 60% relative humidity, various other constraints limit the actual power boost to about 3.8% of the nominal power. For small values of the wet-bulb depression (less than about 5 C or 10 F), the required droplet sizes for complete evaporation become so small (of the order of 5--10 microns with high flow rates) that production of them at the required flow rates is a challenging task.

  1. Performance of Boosted W Boson Identification with the ATLAS Detector

    CERN Document Server

    The ATLAS collaboration

    2014-01-01

    This note presents the performance of a variety of techniques used to identify highly- boosted hadronically-decaying $W$ bosons. The studies presented here are divided into two parts: the first is based on Monte Carlo simulation, and the second compares the simulations to 20.3$\\pm$0.6 fb$^{-1}$ of proton-–proton collisions data collected by the ATLAS detector in 2012 at $\\sqrt{s} = 8$ TeV. Various tagging approaches and different grooming algorithms are compared in simulation, using a signal of large-$R$ jets containing a highly boosted $W$ boson and a background of large-$R$ jets originating from high-momentum light quarks or gluons. These techniques could also be utilised to identify hadronic decays of boosted $Z$ and Higgs bosons. A sample enriched in $t\\bar{t}\\to (W^+b)(W^-\\bar{b}) \\to (q\\bar{q}b)(\\mu \\bar{\

  2. Self-boosting vaccines and their implications for herd immunity.

    Science.gov (United States)

    Arinaminpathy, Nimalan; Lavine, Jennie S; Grenfell, Bryan T

    2012-12-01

    Advances in vaccine technology over the past two centuries have facilitated far-reaching impact in the control of many infections, and today's emerging vaccines could likewise open new opportunities in the control of several diseases. Here we consider the potential, population-level effects of a particular class of emerging vaccines that use specific viral vectors to establish long-term, intermittent antigen presentation within a vaccinated host: in essence, "self-boosting" vaccines. In particular, we use mathematical models to explore the potential role of such vaccines in situations where current immunization raises only relatively short-lived protection. Vaccination programs in such cases are generally limited in their ability to raise lasting herd immunity. Moreover, in certain cases mass vaccination can have the counterproductive effect of allowing an increase in severe disease, through reducing opportunities for immunity to be boosted through natural exposure to infection. Such dynamics have been proposed, for example, in relation to pertussis and varicella-zoster virus. In this context we show how self-boosting vaccines could open qualitatively new opportunities, for example by broadening the effective duration of herd immunity that can be achieved with currently used immunogens. At intermediate rates of self-boosting, these vaccines also alleviate the potential counterproductive effects of mass vaccination, through compensating for losses in natural boosting. Importantly, however, we also show how sufficiently high boosting rates may introduce a new regime of unintended consequences, wherein the unvaccinated bear an increased disease burden. Finally, we discuss important caveats and data needs arising from this work.

  3. Boosted objects and jet substructure at the LHC

    CERN Document Server

    Altheimer, A.; Asquith, L.; Backus Mayes, J.; Bergeaas Kuutmann, E.; Berger, J.; Bjergaard, D.; Bryngemark, L.; Buckley, A.; Butterworth, J.; Cacciari, M.; Campanelli, M.; Carli, T.; Chala, M.; Chen, C.; Chou, J.P.; Cornelissen, Th.; Curtin, D.; Dasgupta, M.; Davison, A.; De Almeida Dias, F.; De Cosa, A.; De Roeck, A.; Debenedetti, C.; Doglioni, C.; Ellis, S.D.; Fassi, F.; Ferrando, J.; Fleischmann, S.; Freytsis, M.; Gonzalez Silva, M.L.; Gonzalez de la Hoz, S.; Guescini, F.; Han, Z.; Hook, A.; Hornig, A.; Izaguirre, E.; Jankowiak, M.; Juknevich, J.; Kaci, M.; Kar, D.; Kasieczka, G.; Kogler, R.; Larkoski, A.; Loch, P.; Lopez Mateos, D.; Marzani, S.; Masetti, L.; Mateu, V.; Miller, D.W.; Mishra, K.; Nef, P.; Nordstrom, K.; Oliver Garcia, E.; Penwell, J.; Pilot, J.; Plehn, T.; Rappoccio, S.; Rizzi, A.; Rodrigo, G.; Safonov, A.; Salam, G.P.; Salt, J.; Schaetzel, S.; Schioppa, M.; Schmidt, A.; Scholtz, J.; Schwartzman, A.; Schwartz, M.; Segala, M.; Son, M.; Soyez, G.; Spannowsky, M.; Stewart, I.; Strom, D.; Swiatlowski, M.; Sanchez Martinez, V.; Takeuchi, M.; Thaler, J.; Thompson, E.; Tran, N.V.; Vermilion, C.; Villaplana, M.; Vos, M.; Wacker, J.; Walsh, J.

    2014-01-01

    This report of the BOOST2012 workshop presents the results of four working groups that studied key aspects of jet substructure. We discuss the potential of the description of jet substructure in first-principle QCD calculations and study the accuracy of state-of-the-art Monte Carlo tools. Experimental limitations of the ability to resolve substructure are evaluated, with a focus on the impact of additional proton proton collisions on jet substructure performance in future LHC operating scenarios. A final section summarizes the lessons learnt during the deployment of substructure analyses in searches for new physics in the production of boosted top quarks.

  4. Diode-Assisted Buck-Boost Voltage-Source Inverters

    DEFF Research Database (Denmark)

    Gao, Feng; Loh, Poh Chiang; Teodorescu, Remus;

    2009-01-01

    This paper proposes a number of diode-assisted buck-boost voltage-source inverters with a unique X-shaped diode-capacitor network inserted between the inverter circuitry and dc source for producing a voltage gain that is comparatively higher than those of other buck-boost conversion techniques....... Using the diode-assisted network, the proposed inverters can naturally configure themselves to perform capacitive charging in parallel and discharging in series to give a higher voltage multiplication factor without compromising waveform quality. In addition, by adopting different front-end circuitries...

  5. Component-Minimized Buck-Boost Voltage Source Inverters

    DEFF Research Database (Denmark)

    Gao, F.; Loh, P.C.; Blaabjerg, Frede;

    2007-01-01

    order to form a distinct neutral potential in the corresponding voltage boost circuitry for correct B4 inverter operation, necessary modifications are derived step by step. The resulted dc networks with symmetrical placement of passive components allow complete charging and equal energy distribution...... between capacitors. Modulation wise, the proposed buck-boost B4 inverters can be controlled using a carefully designed carrier-based pulse-width modulation (PWM) scheme that will always ensure balanced threephase outputs as desired, while simultaneously achieving minimal voltage stress across...

  6. Complexified boost invariance and holographic heavy ion collisions

    CERN Document Server

    Gubser, Steven S

    2015-01-01

    At strong coupling holographic studies have shown that heavy ion collisions do not obey normal boost invariance. Here we study a modified boost invariance through a complex shift in time, and show that this leads to surprisingly good agreement with numerical holographic computations. When including perturbations the agreement becomes even better, both in the hydrodynamic and the far-from-equilibrium regime. One of the main advantages is an analytic formulation of the stress-energy tensor of the longitudinal dynamics of holographic heavy ion collisions.

  7. Boosted objects: a probe of beyond the standard model physics

    Energy Technology Data Exchange (ETDEWEB)

    Abdesselam, A.; Buckingham, R.; Ferrando, J.; Hays, C.; Issever, C.; Karagoz, M.; Lewis, A.; Livermore, S.; Tseng, J. [Univ. of Oxford, Dept. of Physics, Oxford (United Kingdom); Belyaev, A. [Univ. of Southampton, School of Physics and Astronomy, Southampton (United Kingdom); Science and Technology Facilities Council, Rutherford Appleton Lab., Didcot (United Kingdom); Kuutmann, E.B. [Deutsches Elektronen-Synchrotron DESY, Zeuthen (Germany); Bitenc, U. [Albert-Ludwigs-Univ., Fakultaet fuer Mathematik und Physik, Freiburg i.Br. (Germany); Brooijmans, G. [Columbia Univ., Nevis Lab., Irvington, NY (United States); Butterworth, J.; Davison, A. [University College London, Dept. of Physics and Astronomy, London (United Kingdom); Renstrom, P.B. de [Inst. of Nuclear Physics P.A.N., Krakow (Poland); Franzosi, D.B. [Univ. degli Studi di Torino, Dipt. di Fisica Teorica, Turin (Italy); Chapleau, B. [McGill Univ., High Energy Physics Group, Montreal, Quebec (Canada); Dasgupta, M. [Univ. of Manchester, School of Physics and Astronomy, Manchester (United Kingdom); Dolen, J. [Univ. of California, Davis, CA (United States); Ellis, S.; Policchio, A. [Univ. of Washington, Dept. of Physics, Box 351560, Seattle, WA (United States); Fassi, F. [CNRS/CC-IN2P3, Villeurbanne (France); Frandsen, M.T.; March-Russell, J. [Univ. of Oxford, Dalitz Inst. for Theoretical Physics, Dept. of Physics, Oxford (United Kingdom); Frost, J. [Univ. of Cambridge, Cavendish Lab., Cambridge (United Kingdom); Gadfort, T. [Physics Dept., Brookhaven National Lab., Upton, NY (United States); Glover, N.; Richardson, P. [Univ. of Durham, Inst. of Particle Physics Phenomenology, Dept. of Physics, Durham (United Kingdom); Haas, A.; Schwartzman, A.; Strauss, E.; Wacker, J.; Wilson, M.G. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Halkiadakis, E. [Rutgers Univ., Dept. of Physics and Astronomy, Piscataway, NJ (United States)] [and others

    2011-06-15

    We present the report of the hadronic working group of the BOOST2010 workshop held at the University of Oxford in June 2010. The first part contains a review of the potential of hadronic decays of highly boosted particles as an aid for discovery at the LHC and a discussion of the status of tools developed to meet the challenge of reconstructing and isolating these topologies. In the second part, we present new results comparing the performance of jet grooming techniques and top tagging algorithms on a common set of benchmark channels. We also study the sensitivity of jet substructure observables to the uncertainties in Monte Carlo predictions. (orig.)

  8. Boosted Objects: A Probe of Beyond the Standard Model Physics

    Energy Technology Data Exchange (ETDEWEB)

    Abdesselam, A.; /Oxford U.; Kuutmann, E.Bergeaas; /DESY; Bitenc, U.; /Freiburg U.; Brooijmans, G.; /Columbia U.; Butterworth, J.; /University Coll. London; Bruckman de Renstrom, P.; /Cracow, INP; Buarque Franzosi, D.; /Turin U.; Buckingham, R.; /Oxford U.; Chapleau, B.; /McGill U.; Dasgupta, M.; /Manchester U.; Davison, A.; /University Coll. London; Dolen, J.; /UC, Davis; Ellis, S.; /Washington U., Seattle; Fassi, F.; /Lyon, IPN; Ferrando, J.; /Oxford U.; Frandsen, M.T.; /Oxford U.; Frost, J.; /Cambridge U.; Gadfort, T.; /Brookhaven; Glover, N.; /Durham U.; Haas, A.; /SLAC; Halkiadakis, E.; /Rutgers U., Piscataway /INFN, Milan Bicocca /Oxford U. /Ohio State U. /Rutherford /Oxford U. /Oxford U. /Maryland U. /Bristol U. /Princeton U. /Oxford U. /Oxford U. /Arizona U. /Johns Hopkins U. /Oxford U. /Fermilab /Rutherford /Bristol U. /Karlsruhe U., EKP /Weizmann Inst. /Washington U., Seattle /Johns Hopkins U. /Oslo U. /Durham U. /Princeton U. /Paris, LPTHE /CERN /Southern Denmark U., CP3-Origins /Granada U. /SLAC /Rutherford /Toronto U. /Stockholm U., OKC /Stockholm U. /Yale U.; /more authors..

    2012-06-12

    We present the report of the hadronic working group of the BOOST2010 workshop held at the University of Oxford in June 2010. The first part contains a review of the potential of hadronic decays of highly boosted particles as an aid for discovery at the LHC and a discussion of the status of tools developed to meet the challenge of reconstructing and isolating these topologies. In the second part, we present new results comparing the performance of jet grooming techniques and top tagging algorithms on a common set of benchmark channels. We also study the sensitivity of jet substructure observables to the uncertainties in Monte Carlo predictions.

  9. Boosted objects: a probe of beyond the Standard Model physics

    CERN Document Server

    Abdesselam, A; Bitenc, U; Brooijmans, G; Butterworth, J; Bruckman de Renstrom, P; Buarque Franzosi, D; Buckingham, R; Chapleau, B; Dasgupta, M; Davison, A; Dolen, J; Ellis, S; Fassi, F; Ferrando, J; Frandsen, M T; Frost, J; Gadfort, T; Glover, N; Haas, A; Halkiadakis, E; Hamilton, K; Hays, C; Hill, C; Jackson, J; Issever, C; Karagoz, M; Katz, A; Kreczko, L; Krohn, D; Lewis, A; Livermore, S; Loch, P; Maksimovic, P; March-Russell, J; Martin, A; McCubbin, N; Newbold, D; Ott, J; Perez, G; Policchio, A; Rappoccio, S; Raklev, A R; Richardson, P; Salam, G P; Sannino, F; Santiago, J; Schwartzman, A; Shepherd-Themistocleous, C; Sinervo, P; Sjoelin, J; Son, M; Spannowsky, M; Strauss, E; Takeuchi, M; Tseng, J; Tweedie, B; Vermillion, C; Voigt, J; Vos, M; Wacker, J; Wagner-Kuhr, J; Wilson, M G

    2011-01-01

    We present the report of the hadronic working group of the BOOST2010 workshop held at the University of Oxford in June 2010. The first part contains a review of the potential of hadronic decays of highly boosted particles as an aid for discovery at the LHC and a discussion of the status of tools developed to meet the challenge of reconstructing and isolating these topologies. In the second part, we present new results comparing the performance of jet grooming techniques and top tagging algorithms on a common set of benchmark channels. We also study the sensitivity of jet substructure observables to the uncertainties in Monte Carlo predictions.

  10. Design and Analysis of a Proposed Timer Controller with Constant Switching Frequency Boost PFC Converter

    Directory of Open Access Journals (Sweden)

    Mr. D. Lenine

    2011-01-01

    Full Text Available The Proposal of this paper is to introduce a new control technique for power factor correction in ac-dc converters. The increasing of non linear loads such as thyristor rectifiers, switching-mode power supplies and adjustable speed drives, generate harmonic currents causing various problems to the other equipment connected to the point of common coupling. There is a disadvantage in the existing PFC control implementation based on conventional hysteresis current control is variable switching frequency. The proposed control technique, it combines the advantages of conventional hysteresis control strategy and the prominent characteristics of constant switching frequency. The fundamental idea consists in determining the ideal time period that exists between the moment when the input current crosses with the reference current and the converter commutation. Thus the input current can oscillate around the reference current with constant frequency of operation. The principal of operation, theoretical analysis, simulation results on a single phase boost converter are presented.

  11. Integrated Charger with Wireless Charging and Boost Function for PHEV and EV Applications

    Energy Technology Data Exchange (ETDEWEB)

    Chinthavali, Madhu Sudhan [ORNL; Onar, Omer C [ORNL; Campbell, Steven L [ORNL

    2015-01-01

    Integrated charger topologies that have been researched so far with dc-dc converters and the charging functionality have no isolation in the system. Isolation is an important feature that is required for user interface systems that have grid connections and therefore is a major limitation that needs to be addressed along with the integrated functionality. The topology proposed in this paper is a unique and a first of its kind topology that integrates a wireless charging system and the boost converter for the traction drive system. The new topology is also compared with an on-board charger system from a commercial electric vehicle (EV). The ac-dc efficiency of the proposed system is 85.05% and the specific power and power density of the onboard components is ~455 W/kg and ~302 W/ .

  12. Integrated Charger with Wireless Charging and Boost Function for PHEV and EV Applications

    Energy Technology Data Exchange (ETDEWEB)

    Chinthavali, Madhu Sudhan [ORNL; Onar, Omer C [ORNL; Campbell, Steven L [ORNL; Tolbert, Leon M [ORNL

    2015-01-01

    Integrated charger topologies that have been researched so far with dc-dc converters and the charging functionality have no isolation in the system. Isolation is an important feature that is required for user interface systems that have grid connections and therefore is a major limitation that needs to be addressed along with the integrated functionality. The topology proposed in this paper is a unique and a first of its kind topology that integrates a wireless charging system and the boost converter for the traction drive system. The new topology is also compared with an on-board charger system from a commercial electric vehicle (EV). The ac-dc efficiency of the proposed system is 85.1% and the specific power and power density of the onboard components is ~455 W/kg and ~320 W/ .

  13. 78 FR 55684 - ConnectED Workshop

    Science.gov (United States)

    2013-09-11

    ... National Telecommunications and Information Administration ConnectED Workshop AGENCY: National... in the United States to next- generation broadband. This Notice announces that the ConnectED Workshop... ConnectED Workshop will discuss the growing bandwidth needs of K-12 schools as more schools use...

  14. Do High-Risk Young Adults Use the HIV Self-Test Appropriately? Observations from a Think-Aloud Study.

    Science.gov (United States)

    Schnall, Rebecca; John, Rita Marie; Carballo-Dieguez, Alex

    2016-04-01

    The purpose of this study was to understand high-risk young adults' use of the rapid human immunodeficiency virus (HIV) self-test. The highest rate of new HIV infections occurs in people between 15 and 24 years. Improving identification of young people infected with HIV is a critical public health priority. The first rapid HIV self-testing kit was approved in the US in 2012. Despite the product's promise, its use by untrained young adults is not well-understood. We conducted a mixed methods study using surveys, a think-aloud protocol, observations, and in-depth interviews. A systematic checklist was developed to assess participants' use of the test. A total of 21 racial and/or ethnic minority young adults aged 18-24 participated in this study. Analysis of our interview data was guided by the theory of reasoned action (TRA). Participants completed the initial procedures of the test with a mean time of 8:36 min (range of 2:04'-16:33'). On a 14-point checklist, participants had a mean score of 10.8 (SD 2.26, range 3-14). In the qualitative analysis of the participants' interviews, guided by the theoretical constructs of the TRA, the following themes emerged: "Did I use it correctly?", "Can I trust the results?" (attitude); "How will my partner react?!", "What will people think?" (subjective norm); "Quick, easy and blood free," and "Avoids the hassle of dealing with the healthcare system" (behavioral intention). This study provided evidence of the usefulness of the test perceived by young adults, especially in light of their concerns about lack of privacy in medical settings. Since many participants did not follow all of the instructions while using the test, it is not evident that young adults can correctly use the HIV self-test. Development of instructions manuals that are understandable and guide proper use of medical devices is a great need, especially in the context of home testing technology. PMID:26518679

  15. Single-Phase Direct AC-AC Boost Converter

    Directory of Open Access Journals (Sweden)

    LUCANU, M.

    2014-08-01

    Full Text Available The paper presents a single-phase direct AC-AC boost converter. The circuit of the converter is simple and it has good performances, irrespective of the load nature. The adequate functioning and high performance of the circuit (the efficiency and waveform of the absorbed input current were tested both by simulation and experimentally.

  16. Could Weight-Loss Surgery Boost Odds of Preemie Birth?

    Science.gov (United States)

    ... https://medlineplus.gov/news/fullstory_160596.html Could Weight-Loss Surgery Boost Odds of Preemie Birth? Monitoring is ... HealthDay News) -- Mothers-to-be who've had weight-loss surgery may have increased odds for premature delivery, ...

  17. Search for new resonances with boosted signatures at CMS

    CERN Document Server

    CERN. Geneva

    2015-01-01

    The LHC and its experiments are ideally suited to search for these new resonances in order to validate or constrain the corresponding theories. At resonance masses well above 1 TeV, these searches face specific challenges. The decay products have large Lorentz boosts, resulting in very collimated final state topologies. Jet substructure methods and the use of non-isolate...

  18. Flavorings Boost Toxicity of E-Cigarettes in Lab Study

    Science.gov (United States)

    ... news/fullstory_161111.html Flavorings Boost Toxicity of E-Cigarettes in Lab Study Increasing device's voltage, to get ... Sept. 22, 2016 (HealthDay News) -- Flavorings used in e-cigarettes can increase the toxicity of the vapor that ...

  19. Classification of airborne laser scanning data using JointBoost

    Science.gov (United States)

    Guo, Bo; Huang, Xianfeng; Zhang, Fan; Sohn, Gunho

    2015-02-01

    The demands for automatic point cloud classification have dramatically increased with the wide-spread use of airborne LiDAR. Existing research has mainly concentrated on a few dominant objects such as terrain, buildings and vegetation. In addition to those key objects, this paper proposes a supervised classification method to identify other types of objects including power-lines and pylons from point clouds using a JointBoost classifier. The parameters for the learning model are estimated with various features computed based on the geometry and echo information of a LiDAR point cloud. In order to overcome the shortcomings stemming from the inclusion of bare ground data before classification, the proposed classifier directly distinguishes terrain using a feature step-off count. Feature selection is conducted using JointBoost to evaluate feature correlations thus improving both classification accuracy and operational efficiency. In this paper, the contextual constraints for objects extracted by graph-cut segmentation are used to optimize the initial classification results obtained by the JointBoost classifier. Our experimental results show that the step-off count significantly contributes to classification. Seventeen effective features are selected for the initial classification results using the JointBoost classifier. Our experiments indicate that the proposed features and method are effective for classification of airborne LiDAR data from complex scenarios.

  20. Healthy Fats in Mediterranean Diet Won't Boost Weight

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_159217.html Healthy Fats in Mediterranean Diet Won't Boost Weight Vegetable oils, nuts can ... groups, though less so in those on the healthy fat diets. The low-fat group had an increase of ...

  1. Color edge saliency boosting using natural image statistics

    NARCIS (Netherlands)

    D. Rojas Vigo; J. van de Weijer; T. Gevers

    2010-01-01

    State of the art methods for image matching, content-based retrieval and recognition use local features. Most of these still exploit only the luminance information for detection. The color saliency boosting algorithm has provided an efficient method to exploit the saliency of color edges based on in

  2. Modeling brand choice using boosted and stacked neural networks

    NARCIS (Netherlands)

    R. Potharst (Rob); M. van Rijthoven; M.C. van Wezel (Michiel)

    2005-01-01

    textabstractThe brand choice problem in marketing has recently been addressed with methods from computational intelligence such as neural networks. Another class of methods from computational intelligence, the so-called ensemble methods such as boosting and stacking have never been applied to the

  3. High Efficiency Boost Converter with Three State Switching Cell

    DEFF Research Database (Denmark)

    Klimczak, Pawel; Munk-Nielsen, Stig

    2009-01-01

    The boost converter with the three-state switching cell seems to be a good candidate for a dc-dc stage for non-isolated generators based on alternative energy sources. It provides a high voltage gain, a reduced voltage stress on transistors and limited input current ripples. In this paper the focus...

  4. Early Boost and Slow Consolidation in Motor Skill Learning

    Science.gov (United States)

    Hotermans, Christophe; Peigneux, Philippe; de Noordhout, Alain Maertens; Moonen, Gustave; Maquet, Pierre

    2006-01-01

    Motor skill learning is a dynamic process that continues covertly after training has ended and eventually leads to delayed increments in performance. Current theories suggest that this off-line improvement takes time and appears only after several hours. Here we show an early transient and short-lived boost in performance, emerging as early as…

  5. Integrated Current Balancing Transformer for Primary Parallel Isolated Boost Converter

    DEFF Research Database (Denmark)

    Sen, Gökhan; Ouyang, Ziwei; Thomsen, Ole Cornelius;

    2011-01-01

    A simple, PCB compatible integrated solution is proposed for the current balancing requirement of the primary parallel isolated boost converter (PPIBC). Input inductor and the current balancing transformer are merged into the same core, which reduces the number of components allowing a cheaper...

  6. Wide Temperature Range DC-DC Boost Converters for Command/Control/Drive Electronics Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We shall develop wide temperature range DC-DC boost converters that can be fabricated using commercial CMOS foundries. The boost converters will increase the low...

  7. Discordant connections

    OpenAIRE

    Arora-Jonsson, Seema

    2009-01-01

    The importance of gender-equality and of women’s work in relation to the environment are considered to be crucial questions for development in ‘third world’ rural societies. ‘Development’ and a certain standard of welfare make these issues appear to be less urgent in a wealthier country like Sweden. In this paper I trace some of the contradictions and connections in the ways in which gender equality is conceptualised in women’s struggles vis á vis environmental issues in rural areas in Swede...

  8. Topological Design and Modulation Strategy for Buck-Boost Three-Level Inverters

    DEFF Research Database (Denmark)

    Teodorescu, Remus; Gao, F.; Blaabjerg, Frede;

    2007-01-01

    buck-boost three-level inverters that can also support bidirectional power conversion. The proposed front-end circuitry is developed from the ¿uk-derived buck-boost two-level inverter, and by using the "alternative phase opposition disposition" (APOD) modulation scheme, the buck-boost three......-level inverters can perform distinct five-level line voltage and three-level phase voltage switching by simply controlling the active switches located in the designed voltage boost section of the circuits. As a cost saving option, one active switch can further be removed from the voltage-boost section...

  9. "Even 'Daily' is Not Enough": How Well Do We Measure Domestic Violence and Abuse?-A Think-Aloud Study of a Commonly Used Self-Report Scale.

    Science.gov (United States)

    Evans, Maggie; Gregory, Alison; Feder, Gene; Howarth, Emma; Hegarty, Kelsey

    2016-01-01

    This article explores the challenges of providing a quantitative measure of domestic violence and abuse (DVA), illustrated by the Composite Abuse Scale, a validated multidimensional measure of frequency and severity of abuse, used worldwide for prevalence studies and intervention trials. Cognitive "think-aloud" and qualitative interviewing with a sample of women who had experienced DVA revealed a tendency toward underreporting their experience of abuse, particularly of coercive control, threatening behavior, restrictions to freedom, and sexual abuse. Underreporting was linked to inconsistency and uncertainty in item interpretation and response, fear of answering truthfully, and unwillingness to identify with certain forms of abuse. Suggestions are made for rewording or reconceptualizing items and the inclusion of a distress scale to measure the individual impact of abuse. The importance of including qualitative methods in questionnaire design and in the interpretation of quantitative findings is highlighted. PMID:26645540

  10. Comparing the performance and preference of students experiencing a Reading Aloud Accommodation to those who do not on a virtual science assessment

    Science.gov (United States)

    Shelton, Angela

    Many United States secondary students perform poorly on standardized summative science assessments. Situated Assessments using Virtual Environments (SAVE) Science is an innovative assessment project that seeks to capture students' science knowledge and understanding by contextualizing problems in a game-based virtual environment called Scientopolis. Within Scientopolis, students use an "avatar" to interact with non-player characters (NPCs), artifacts, embedded clues and "sci-tools" in order to help solve the problems of the townspeople. In an attempt to increase students' success on assessments, SAVE science places students in an environment where they can use their inquiry skills to solve problems instead of reading long passages which attempt to contextualize questions but ultimately cause construct-irrelevant variance. However, within these assessments reading is still required to access the test questions and character interactions. This dissertation explores how students' in-world performances differ when exposed to a Reading Aloud Accommodation (RAA) treatment in comparison to a control group. Student perceptions of the treatment are also evaluated. While a RAA is typically available for students with learning disabilities or English language learners, within this study, all students were randomly assigned to either the treatment or control, regardless of any demographic factors or learning barriers. The theories of Universal design for learning and brain-based learning advocate for multiple ways for students to engage, comprehend, and illustrate their content knowledge. Further, through providing more ways for students to interact with content, all students should benefit, not just those with learning disabilities. Students in the experimental group listened to the NPCs speak the dialogue that provides them with the problem, clues, and assessment questions, instead of relying on reading skills to gather the information. Overall, students in the treatment

  11. Places Connected:

    DEFF Research Database (Denmark)

    Hansen, Annette Skovsted

    Nations Volunteer of Japanese nationality. Networks of personal ties, ideas, feelings, and material culture. By combining work on the experience of place with network historiography on migration and kinship, the paper presents a case on the function of the temporary encounter in human networks....... experience the places of Denmark and Japan temporarily integrate the national histories of these two countries in the histories of their home countries and vice versa. Thereby, I wish to offer a dynamic understanding of development history and globalization, which challenges the nationally bound histories...... experiences of place, however, when it is often the same people who experience many different places? Along with many other so-called donors in the 1950s, Denmark and Japan chose to invest in the education of own and other nationals involved in development and thereby financed personal connections between...

  12. Bifurcation behaviours of peak current controlled PFC boost converter

    Institute of Scientific and Technical Information of China (English)

    Ren Hai-Peng; Liu Ding

    2005-01-01

    Bifurcation behaviours of the peak current controlled power-factor-correction (PFC) boost converter, including fast-scale instability and low-frequency bifurcation, are investigated in this paper. Conventionally, the PFC converter is analysed in continuous conduction mode (CCM). This prevents us from recognizing the overall dynamics of the converter. It has been pointed out that the discontinuous conduction mode (DCM) can occur in the PFC boost converter, especially in the light load condition. Therefore, the DCM model is employed to analyse the PFC converter to cover the possible DCM operation. By this way, the low-frequency bifurcation diagram is derived, which makes the route from period-double bifurcation to chaos clear. The bifurcation diagrams versus the load resistance and the output capacitance also indicate the stable operation boundary of the converter, which is useful for converter design.

  13. Black brane entropy and hydrodynamics: The boost-invariant case

    International Nuclear Information System (INIS)

    The framework of slowly evolving horizons is generalized to the case of black branes in asymptotically anti-de Sitter spaces in arbitrary dimensions. The results are used to analyze the behavior of both event and apparent horizons in the gravity dual to boost-invariant flow. These considerations are motivated by the fact that at second order in the gradient expansion the hydrodynamic entropy current in the dual Yang-Mills theory appears to contain an ambiguity. This ambiguity, in the case of boost-invariant flow, is linked with a similar freedom on the gravity side. This leads to a phenomenological definition of the entropy of black branes. Some insights on fluid/gravity duality and the definition of entropy in a time-dependent setting are elucidated.

  14. Boosted H­->bb Tagger In Run II

    CERN Document Server

    Sahinsoy, Merve; The ATLAS collaboration

    2016-01-01

    Several searches for Higgs bosons decaying to b­quark pairs benefit from the increased Run II centre­of­mass energy by exploiting the large transvers­momentum (boosted) Higgs boson regime, where the two b­jets are merged into one large­radius jet. ATLAS uses a boosted H­>bb tagger algorithm to separate the Higgs signal from the background processes (QCD, W and Z bosons, top quarks). The tagger takes as input a large­R=1.0 jet calibrating the pseudorapidity, energy and mass scale. The tagger employs b­tagging, Higgs candidate mass, and substructure information. The performance of several operating points in Higgs boson signal and QCD and ttbar all­hadronic backgrounds are presented. Systematic uncertainties are evaluated so that this tagger can be used in analyses.

  15. Energy profile of b-jet for boosted top quarks

    Directory of Open Access Journals (Sweden)

    Kitadono Yoshio

    2014-01-01

    Full Text Available We analyse the semileptonic decay of a polarised top-quark with a large velocity based on the perturbative QCD factorisation framework. Thanks to the factorisation and the spin decomposition, the production part and the decay part can be factorised and the spin dependence is introduced in the decay part. The decay part is converted to the top-jet function which describes the distribution of jet observables and the spin is translated to the helicity of the boosted top. Using this top-jet function, the energy profile of b-jet is investigated and it is turned out that the sub-jet energy for the helicity-minus top is accumulated faster than that for the helicity-plus top. This behaviour for the boosted top can be understood with the negative spin-analysing-power of b-quark in the polarised-top decay.

  16. Improved Parallel Boost Power Converter for Power Factor Correction

    Directory of Open Access Journals (Sweden)

    T. Ajith Bosco Raj

    2014-06-01

    Full Text Available The main objective of the study is to analysis and design parallel boost power converter for power factor correction using an active filtering approach by implementing single-phase soft-switching technique with an active snubber circuit. Zero voltage transition to turn ON and zero current transition to turn OFF is implemented by the active snubber circuit for the main switches with no any further current or voltage strains. By zero-current switching without the need of added voltage stress, auxiliary switch is turned ON and OFF. The proposed converter has simple structure, low cost and ease of control. The efficiency, which is about 96% in hard switching, will increases to about 98% in the proposed soft-switching parallel boost converter.

  17. A Two-Stage Wind Grid Inverter with Boost Converter

    Directory of Open Access Journals (Sweden)

    Yanbo Che

    2014-01-01

    Full Text Available At present, the conversion efficiency of commercial small wind grid inverter is low, and, in case of low wind speed, the wind energy cannot be used efficiently. In order to resolve this problem, it is necessary to improve the topological structure and control strategy, and design a new small wind grid inverter. In this paper, we apply a two-voltage stage topology with boost converter. The boost circuit is to achieve the maximum power output of the wind energy by the segmented regulation, while the improved inverter topology realizes the overall system function with the former stage circuit. The experimental results show that the new wind grid inverter has superior performance in the low wind speed, and has the high quality energy output. This research has an important practical significance to improve the utilization of renewable energy.

  18. A Single Switch Dual Output Non-Isolated Boost Converter

    DEFF Research Database (Denmark)

    Klimczak, Pawel; Munk-Nielsen, Stig

    2008-01-01

    very simple dual output non-isolated boost converter is presented. Single active switch is used to control both, positive and negative output voltages. The converter is desired to boost unregulated low input voltage 25-50 Vdc to regulated high voltage ±400 Vdc in dual dc-link. In this paper proposed...... topology is analyzed and explained. Obtained experimental results prove good performance of the converter over wide range of input voltage and output power.......There are many applications for high gain dc-dc converters. In several of these applications galvanic isolation is not required, but there are some safety issues regarding missing isolation and leakage current. Usage of a half-bridge inverter and a dual dc-link may solve this issues. In this paper...

  19. Bifurcation behaviours of peak current controlled PFC boost converter

    Science.gov (United States)

    Ren, Hai-Peng; Liu, Ding

    2005-07-01

    Bifurcation behaviours of the peak current controlled power-factor-correction (PFC) boost converter, including fast-scale instability and low-frequency bifurcation, are investigated in this paper. Conventionally, the PFC converter is analysed in continuous conduction mode (CCM). This prevents us from recognizing the overall dynamics of the converter. It has been pointed out that the discontinuous conduction mode (DCM) can occur in the PFC boost converter, especially in the light load condition. Therefore, the DCM model is employed to analyse the PFC converter to cover the possible DCM operation. By this way, the low-frequency bifurcation diagram is derived, which makes the route from period-double bifurcation to chaos clear. The bifurcation diagrams versus the load resistance and the output capacitance also indicate the stable operation boundary of the converter, which is useful for converter design.

  20. Performance of boosted object and jet substructure techniques

    CERN Document Server

    Schramm, Steven; The ATLAS collaboration

    2016-01-01

    Hadronic decays of heavy particles with momenta much larger than their mass result in their decay products being reconstructable as a single large ­radius jet. The study of the substructure of these jets allows the separation of these boosted decays with respect to more common jets from light­ quarks and gluons. Several techniques have been developed by the phenomenology and experimental community to identify jets coming from hadronic decays of boosted top quarks, W, Z and Higgs bosons. The performance of several such techniques have been studied in ATLAS using fully­ simulated Monte Carlo events, and validated on data using pure samples of top quarks, W bosons from top decays and dijet events. Results of these studies will be presented for Run 1 as well as Run 2 of the LHC.

  1. Three Phase High Power Quality Two- Stage Boost Rectifier

    Directory of Open Access Journals (Sweden)

    P.NAMMALVAR

    2012-04-01

    Full Text Available Three-phase two-stage boost rectifier with sinusoidal input current are presented and a novel topology with two active power devices is proposed. These contain a capacitor for pumping action in DC circuit. This gives twostage boost operation to obtain higher DC output voltage. The rectifier can be operated in the switch mode forpumping action and for forcing the input current to follow its sinusoidal reference independent of the working conditions. The results of the proposed rectifier are compared with those of the rectifier with a single active power device. The simulation result gives the better output DC voltage regulation under open loop condition. The simulated results prove that the proposed rectifier has the expected performance.

  2. AdaBoost for Improved Voice-Band Signal Classification

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A good voice-band signal classification can not only enable the safe application of speech coding techniques,the implementation of a Digital Signal Interpolation (DSI)system, but also facilitate network administration and planning by providing accurate voice-band traffic analysis.A new method is proposed to detect and classify the presence of various voice-band signals on the General Switched Telephone Network ( GSTN ). The method uses a combination of simple base classifiers through the AdaBoost algorithm. The conventional classification features for voiceband data classification are combined and optimized by the AdaBoost algorithm and spectral subtraction method.Experiments show the simpleness, effectiveness, efficiency and flexibility of the method.

  3. Novel Intrusion Detection using Probabilistic Neural Network and Adaptive Boosting

    CERN Document Server

    Tran, Tich Phuoc; Tran, Dat; Nguyen, Cuong Duc

    2009-01-01

    This article applies Machine Learning techniques to solve Intrusion Detection problems within computer networks. Due to complex and dynamic nature of computer networks and hacking techniques, detecting malicious activities remains a challenging task for security experts, that is, currently available defense systems suffer from low detection capability and high number of false alarms. To overcome such performance limitations, we propose a novel Machine Learning algorithm, namely Boosted Subspace Probabilistic Neural Network (BSPNN), which integrates an adaptive boosting technique and a semi parametric neural network to obtain good tradeoff between accuracy and generality. As the result, learning bias and generalization variance can be significantly minimized. Substantial experiments on KDD 99 intrusion benchmark indicate that our model outperforms other state of the art learning algorithms, with significantly improved detection accuracy, minimal false alarms and relatively small computational complexity.

  4. How citation boosts promote scientific paradigm shifts and Nobel Prizes

    CERN Document Server

    Mazloumian, Amin; Helbing, Dirk; Lozano, Sergi; Fortunato, Santo; 10.1371/journal.pone.0018975

    2011-01-01

    Nobel Prizes are commonly seen to be among the most prestigious achievements of our times. Based on mining several million citations, we quantitatively analyze the processes driving paradigm shifts in science. We find that groundbreaking discoveries of Nobel Prize Laureates and other famous scientists are not only acknowledged by many citations of their landmark papers. Surprisingly, they also boost the citation rates of their previous publications. Given that innovations must outcompete the rich-gets-richer effect for scientific citations, it turns out that they can make their way only through citation cascades. A quantitative analysis reveals how and why they happen. Science appears to behave like a self-organized critical system, in which citation cascades of all sizes occur, from continuous scientific progress all the way up to scientific revolutions, which change the way we see our world. Measuring the "boosting effect" of landmark papers, our analysis reveals how new ideas and new players can make their...

  5. Content-boosted Matrix Factorization Techniques for Recommender Systems

    OpenAIRE

    Nguyen, Jennifer; Zhu, Mu

    2012-01-01

    Many businesses are using recommender systems for marketing outreach. Recommendation algorithms can be either based on content or driven by collaborative filtering. We study different ways to incorporate content information directly into the matrix factorization approach of collaborative filtering. These content-boosted matrix factorization algorithms not only improve recommendation accuracy, but also provide useful insights about the contents, as well as make recommendations more easily inte...

  6. Modeling and Control of Primary Parallel Isolated Boost Converter

    DEFF Research Database (Denmark)

    Mira Albert, Maria del Carmen; Hernandez Botella, Juan Carlos; Sen, Gökhan;

    2012-01-01

    In this paper state space modeling and closed loop controlled operation have been presented for primary parallel isolated boost converter (PPIBC) topology as a battery charging unit. Parasitic resistances have been included to have an accurate dynamic model. The accuracy of the model has been...... tested by comparing the calculated and measured loop gains. The designed controller has been implemented in a DSP based control circuit and stable operation of the converter has been achieved....

  7. Bagged Boosted Trees for Classification of Ecological Momentary Assessment Data

    OpenAIRE

    Spanakis, Gerasimos; Weiss, Gerhard; Roefs, Anne

    2016-01-01

    Ecological Momentary Assessment (EMA) data is organized in multiple levels (per-subject, per-day, etc.) and this particular structure should be taken into account in machine learning algorithms used in EMA like decision trees and its variants. We propose a new algorithm called BBT (standing for Bagged Boosted Trees) that is enhanced by a over/under sampling method and can provide better estimates for the conditional class probability function. Experimental results on a real-world dataset show...

  8. How Citation Boosts Promote Scientific Paradigm Shifts and Nobel Prizes

    OpenAIRE

    Amin Mazloumian; Young-Ho Eom; Dirk Helbing; Sergi Lozano; Santo Fortunato

    2011-01-01

    Nobel Prizes are commonly seen to be among the most prestigious achievements of our times. Based on mining several million citations, we quantitatively analyze the processes driving paradigm shifts in science. We find that groundbreaking discoveries of Nobel Prize Laureates and other famous scientists are not only acknowledged by many citations of their landmark papers. Surprisingly, they also boost the citation rates of their previous publications. Given that innovations must outcompete the ...

  9. Dark matter conversion as a source of boost factor

    Science.gov (United States)

    Liu, Ze-Peng; Wu, Yue-Liang; Zhou, Yu-Feng

    2012-09-01

    In interacting multi-component dark matter (DM) models, the interactions between the DM components can covert relatively heavy DM components into lighter ones at late times after the thermal decoupling. As a consequence, the relic density of the lightest DM component can be greatly enhanced at late times, which can lead to an alternative source of boost factor required to explain the positron and electron excesses reported by the recent DM indirect search experiments.

  10. Corrector del factor de potencia mediante convertidor boost multifase

    OpenAIRE

    Barriocanal Escobar, Jordi

    2009-01-01

    Las fuentes de alimentación tradicionales provocan una clara disminución del factor de potencia. Es necesario encontrar un circuito que pase la corr iente alterna a corriente continua, con un elevado factor de potencia. Para ello se puede utilizar un convertidor de poten cia Boost posterior a un rectificador. Se aumenta el factor de potencia pero en la tensión de salida aparece un rizado de baja frecuenci...

  11. Improved Parallel Boost Power Converter for Power Factor Correction

    OpenAIRE

    T. Ajith Bosco Raj; Ramesh, R.

    2014-01-01

    The main objective of the study is to analysis and design parallel boost power converter for power factor correction using an active filtering approach by implementing single-phase soft-switching technique with an active snubber circuit. Zero voltage transition to turn ON and zero current transition to turn OFF is implemented by the active snubber circuit for the main switches with no any further current or voltage strains. By zero-current switching without the need of added voltage stress, a...

  12. Isolated Boost Converter with Bidirectional Operation for Supercapacitor Applications

    DEFF Research Database (Denmark)

    Hernandez Botella, Juan Carlos; Mira Albert, Maria del Carmen; Sen, Gökhan;

    2013-01-01

    This paper presents an isolated bidirectional dc/dc converter based on primary parallel isolated boost converter (PPIBC). This topology is an efficient solution in low voltage high power applications due to its ability to handle high currents in the low voltage side. In this paper, the converter...... interconnecting two battery banks. A second prototype has been constructed and tested for supercapacitor operation in constant power charge mode....

  13. Boosting Sharing Economy: Social Welfare or Revenue Driven?

    OpenAIRE

    Fang, Zhixuan; Huang, Longbo

    2016-01-01

    Product sharing over online platforms, or sharing economy, has become a growing trend and has the potential to mitigate many social problems such as wasted products, idle resources, road congestions, and even greenhouse gas emissions.Despite its quick and successful development so far, there has been a lack of clear understanding about who is a better candidate for boosting sharing economy: government-like organizations who care about social welfare, or profit-driven entities who mainly focus...

  14. The Voltage Boost Enabled by Luminescence Extraction in Solar Cells

    Energy Technology Data Exchange (ETDEWEB)

    Ganapati, Vidya; Steiner, Myles A.; Yablonovitch, Eli

    2016-07-01

    Over the past few years, the application of the physical principle, i.e., 'luminescence extraction,' has produced record voltages and efficiencies in photovoltaic cells. Luminescence extraction is the use of optical design, such as a back mirror or textured surfaces, to help internal photons escape out of the front surface of a solar cell. The principle of luminescence extraction is exemplified by the mantra 'a good solar cell should also be a good LED.' Basic thermodynamics says that the voltage boost should be related to concentration ratio C of a resource by ..delta..V = (kT/q) ln{C}. In light trapping (i.e., when the solar cell is textured and has a perfect back mirror), the concentration ratio of photons C = {4n2}; therefore, one would expect a voltage boost of ..delta..V = (kT/q) ln{4n2} over a solar cell with no texture and zero back reflectivity, where n is the refractive index. Nevertheless, there has been ambiguity over the voltage benefit to be expected from perfect luminescence extraction. Do we gain an open-circuit voltage boost of ..delta..V = (kT/q) ln{n2}, ..delta..V = (kT/q) ln{2 n2}, or ..delta..V = (kT/q) ln{4 n2}? What is responsible for this voltage ambiguity ..delta..V = (kT/q) ln{4} [equivalent to] 36 mV? We show that different results come about, depending on whether the photovoltaic cell is optically thin or thick to its internal luminescence. In realistic intermediate cases of optical thickness, the voltage boost falls in between: ln{n2} < (q..delta..V/kT) < ln{4n 2}.

  15. Concurrent Boost with Adjuvant Breast Hypofractionated Radiotherapy and Toxicity Assessment

    Directory of Open Access Journals (Sweden)

    Mona M. Sayed

    2015-01-01

    Full Text Available Background: The use of shorter radiotherapy schedules has an economic and logistic advantage for radiotherapy departments, as well as a high degree of patient convenience. The aim of this study is to assess the acute and short-term late toxicities of a hypofractionated radiotherapy schedule with a concomitant boost. Methods: We enrolled 57 eligible patients as group A. These patients received 42.5 Gy in 16 fractions of 2.66 Gy each to the whole breast over 3.2 weeks. A concomitant electron boost of 12 Gy in 16 fractions was also administered which gave an additional 0.75 Gy daily to the lumpectomy area for a total radiation dose of 54.5 Gy. Toxicity was recorded at three weeks and at three months for this group as well as for a control group (group B. The control group comprised 76 eligible patients treated conventionally with 50 Gy to the whole breast over five weeks followed by a sequential electron boost of 12 Gy in 2 Gy per fraction. Results: There were no statistically significant differences observed in the incidence of acute skin toxicity, breast pain, and edema recorded at three weeks or pigmentation and fibrosis recorded at three months between the two groups (P0.05. Conclusion: The results of this study suggest there are no increased acute and shortterm late toxicities affiliated with the hypofractionated schedule plus a concomitant boost as prescribed compared to the conventional fractionation of adjuvant breast radiotherapy. Large randomized trials and long-term follow-up are needed to confirm these favorable findings.

  16. A Novel High Performance Bridgeless Ac-Dc Boost Converter

    Directory of Open Access Journals (Sweden)

    S.M.AshrafulAlam Mohon

    2016-08-01

    Full Text Available A new single phase high performance bridgeless AC-DC Boost converter is proposed. The converter is made bridgeless by the use of two unidirectional switches and two diodes at the input ac side for power conversion for both positive and negative half cycle. Because of the high frequency switching, the power factor of the circuit is inherently corrected and it requires a small filter to make the input current near sinusoidal with limited THD. The significant improvement in THD makes the circuit a good choice in applications needing AC-DC conversion with power conditioning. The circuit exhibits such better performances than conventional AC-DC boost converter with variable loads at constant frequency switching with no additional control circuits. The efficiency of the circuit is also satisfactory. Analysis and simulation results of the circuit are obtained by using software simulation. The main advantage of this new AC-DC converter is its superior power quality over conventional AC-DC boost converter

  17. Boosted dark matter signals uplifted with self-interaction

    International Nuclear Information System (INIS)

    We explore detection prospects of a non-standard dark sector in the context of boosted dark matter. We focus on a scenario with two dark matter particles of a large mass difference, where the heavier candidate is secluded and interacts with the standard model particles only at loops, escaping existing direct and indirect detection bounds. Yet its pair annihilation in the galactic center or in the Sun may produce boosted stable particles, which could be detected as visible Cherenkov light in large volume neutrino detectors. In such models with multiple candidates, self-interaction of dark matter particles is naturally utilized in the assisted freeze-out mechanism and is corroborated by various cosmological studies such as N-body simulations of structure formation, observations of dwarf galaxies, and the small scale problem. We show that self-interaction of the secluded (heavier) dark matter greatly enhances the capture rate in the Sun and results in promising signals at current and future experiments. We perform a detailed analysis of the boosted dark matter events for Super-Kamiokande, Hyper-Kamiokande and PINGU, including notable effects such as evaporation due to self-interaction and energy loss in the Sun

  18. Coevolution of synchronous activity and connectivity in coupled chaotic oscillators.

    Science.gov (United States)

    Chen, Li; Qiu, Can; Huang, Hongbin; Qi, Guanxiao; Wang, Haijun

    2010-11-01

    We investigate the coevolution dynamics of node activities and coupling strengths in coupled chaotic oscillators via a simple threshold adaptive scheme. The coupling strength is synchronous activity regulated, which in turn is able to boost the synchronization remarkably. In the case of weak coupling, the globally coupled oscillators present a highly clustered functional connectivity with a power-law distribution in the tail with γ≃3.1 , while for strong coupling, they self-organize into a network with a heterogeneously rich connectivity at the onset of synchronization but exhibit rather sparse structure to maintain the synchronization in noisy environment. The relevance of the results is briefly discussed.

  19. A Comparison of Boosting Tree and Gradient Treeboost Methods for Carpal Tunnel Syndrome

    Directory of Open Access Journals (Sweden)

    Gülhan OREKİCİ TEMEL

    2014-10-01

    Full Text Available Objective: Boosting is one of the most successful combining methods. The principal aim of these combining algorithms is to obtain a strong classifier with small estimation error from the combination of weak classifiers. Boosting based on combining tree has many advantages. Data sets can contain mixtures of nominal, ordinal and numerical variables. AdaBoost and Gradient TreeBoost are commonly used boosting procedure. Both methods are a stage wise additive model fitting procedure. Our goal in this study is to explain the both method and to compare the algorithm results on a neurology data set on the purpose of classification. Material and Methods: The data set consists of 4076 incidences in total. The condition of being a patient with Carpal Tunnel Syndrome (CTS or not was considered as the dependent variable. Boosting Tree and Gradient TreeBoost applications were conducted in Statistica 7.0 and Salford Predictive Modeler: TreeNet (R trial version 6.6.0.091. Results: In AdaBoost and Gradient TreeBoost algorithm, multiple trees are grown of the training data. 200 trees are produced for both models. 70 trees in the AdaBoost Algorithm and 196 trees in the Gradient TreeBoost algorithm are chosen as the optimal trees. Conclusion: The sensitivity or specify values in the test data of Gradient TreeBoost are high indicates that they can be used as a successful method in CTS diagnosis. . It is believed that the boosting methods will become very more and more popular in health science due to its easy implementation and high predictive performance.

  20. Simulation and Implementation of Interleaved Boost DC-DC Converter for Fuel Cell Application

    Directory of Open Access Journals (Sweden)

    Ahmad Saudi Samosir

    2011-10-01

    Full Text Available This paper deals with a boost dc-dc converter for fuel cell application. In fuel cell electric vehicles application, a high power boost dc-dc converter is adopted to adjust the output voltage, current and power of fuel cell engine to meet the vehicle requirements. One of challenge in designing a boost converter for high power application is how to handle the high current at the input side. In this paper an interleaved boost dc-dc converter is proposed for current sharing on high power application. Moreover, this converter also reduces the fuel ripple current. Performance of the interleaved boost converter is tested through simulation and experimental results. Keywords: component; Interleaved Boost Converter; Fuel Cell Electric Vehicle; high power application.  

  1. How Citation Boosts Promote Scientific Paradigm Shifts and Nobel Prizes

    Science.gov (United States)

    Mazloumian, Amin; Eom, Young-Ho; Helbing, Dirk; Lozano, Sergi; Fortunato, Santo

    2011-01-01

    Nobel Prizes are commonly seen to be among the most prestigious achievements of our times. Based on mining several million citations, we quantitatively analyze the processes driving paradigm shifts in science. We find that groundbreaking discoveries of Nobel Prize Laureates and other famous scientists are not only acknowledged by many citations of their landmark papers. Surprisingly, they also boost the citation rates of their previous publications. Given that innovations must outcompete the rich-gets-richer effect for scientific citations, it turns out that they can make their way only through citation cascades. A quantitative analysis reveals how and why they happen. Science appears to behave like a self-organized critical system, in which citation cascades of all sizes occur, from continuous scientific progress all the way up to scientific revolutions, which change the way we see our world. Measuring the “boosting effect” of landmark papers, our analysis reveals how new ideas and new players can make their way and finally triumph in a world dominated by established paradigms. The underlying “boost factor” is also useful to discover scientific breakthroughs and talents much earlier than through classical citation analysis, which by now has become a widespread method to measure scientific excellence, influencing scientific careers and the distribution of research funds. Our findings reveal patterns of collective social behavior, which are also interesting from an attention economics perspective. Understanding the origin of scientific authority may therefore ultimately help to explain how social influence comes about and why the value of goods depends so strongly on the attention they attract. PMID:21573229

  2. How citation boosts promote scientific paradigm shifts and nobel prizes.

    Directory of Open Access Journals (Sweden)

    Amin Mazloumian

    Full Text Available Nobel Prizes are commonly seen to be among the most prestigious achievements of our times. Based on mining several million citations, we quantitatively analyze the processes driving paradigm shifts in science. We find that groundbreaking discoveries of Nobel Prize Laureates and other famous scientists are not only acknowledged by many citations of their landmark papers. Surprisingly, they also boost the citation rates of their previous publications. Given that innovations must outcompete the rich-gets-richer effect for scientific citations, it turns out that they can make their way only through citation cascades. A quantitative analysis reveals how and why they happen. Science appears to behave like a self-organized critical system, in which citation cascades of all sizes occur, from continuous scientific progress all the way up to scientific revolutions, which change the way we see our world. Measuring the "boosting effect" of landmark papers, our analysis reveals how new ideas and new players can make their way and finally triumph in a world dominated by established paradigms. The underlying "boost factor" is also useful to discover scientific breakthroughs and talents much earlier than through classical citation analysis, which by now has become a widespread method to measure scientific excellence, influencing scientific careers and the distribution of research funds. Our findings reveal patterns of collective social behavior, which are also interesting from an attention economics perspective. Understanding the origin of scientific authority may therefore ultimately help to explain how social influence comes about and why the value of goods depends so strongly on the attention they attract.

  3. How citation boosts promote scientific paradigm shifts and nobel prizes.

    Science.gov (United States)

    Mazloumian, Amin; Eom, Young-Ho; Helbing, Dirk; Lozano, Sergi; Fortunato, Santo

    2011-05-04

    Nobel Prizes are commonly seen to be among the most prestigious achievements of our times. Based on mining several million citations, we quantitatively analyze the processes driving paradigm shifts in science. We find that groundbreaking discoveries of Nobel Prize Laureates and other famous scientists are not only acknowledged by many citations of their landmark papers. Surprisingly, they also boost the citation rates of their previous publications. Given that innovations must outcompete the rich-gets-richer effect for scientific citations, it turns out that they can make their way only through citation cascades. A quantitative analysis reveals how and why they happen. Science appears to behave like a self-organized critical system, in which citation cascades of all sizes occur, from continuous scientific progress all the way up to scientific revolutions, which change the way we see our world. Measuring the "boosting effect" of landmark papers, our analysis reveals how new ideas and new players can make their way and finally triumph in a world dominated by established paradigms. The underlying "boost factor" is also useful to discover scientific breakthroughs and talents much earlier than through classical citation analysis, which by now has become a widespread method to measure scientific excellence, influencing scientific careers and the distribution of research funds. Our findings reveal patterns of collective social behavior, which are also interesting from an attention economics perspective. Understanding the origin of scientific authority may therefore ultimately help to explain how social influence comes about and why the value of goods depends so strongly on the attention they attract.

  4. How citation boosts promote scientific paradigm shifts and nobel prizes.

    Science.gov (United States)

    Mazloumian, Amin; Eom, Young-Ho; Helbing, Dirk; Lozano, Sergi; Fortunato, Santo

    2011-01-01

    Nobel Prizes are commonly seen to be among the most prestigious achievements of our times. Based on mining several million citations, we quantitatively analyze the processes driving paradigm shifts in science. We find that groundbreaking discoveries of Nobel Prize Laureates and other famous scientists are not only acknowledged by many citations of their landmark papers. Surprisingly, they also boost the citation rates of their previous publications. Given that innovations must outcompete the rich-gets-richer effect for scientific citations, it turns out that they can make their way only through citation cascades. A quantitative analysis reveals how and why they happen. Science appears to behave like a self-organized critical system, in which citation cascades of all sizes occur, from continuous scientific progress all the way up to scientific revolutions, which change the way we see our world. Measuring the "boosting effect" of landmark papers, our analysis reveals how new ideas and new players can make their way and finally triumph in a world dominated by established paradigms. The underlying "boost factor" is also useful to discover scientific breakthroughs and talents much earlier than through classical citation analysis, which by now has become a widespread method to measure scientific excellence, influencing scientific careers and the distribution of research funds. Our findings reveal patterns of collective social behavior, which are also interesting from an attention economics perspective. Understanding the origin of scientific authority may therefore ultimately help to explain how social influence comes about and why the value of goods depends so strongly on the attention they attract. PMID:21573229

  5. Reading aloud and solving simple arithmetic calculation intervention (Learning therapy) improves inhibition, verbal episodic memory, focus attention, and processing speed in healthy elderly people: Evidence from a randomized controlled trial

    OpenAIRE

    Rui eNouchi; Yasuyuki eTaki; Hikaru eTakeuchi; Takayuki eNozawa; Atsushi eSekiguchi; Ryuta eKawashima

    2016-01-01

    BackgroundPrevious reports have described that simple cognitive training using reading aloud and solving simple arithmetic calculations, so-called learning therapy, can improve executive functions and processing speed in the older adults. Nevertheless, it is not well-known whether learning therapy improve a wide range of cognitive functions or not. We investigated the beneficial effects of learning therapy on various cognitive functions in healthy older adults.MethodsWe used a single-blinde...

  6. China Aims to Boost Emerging Industries for Low Carbon Economy

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    @@ China is making concrete steps in pushing forward with its low-carbon economy by boosting strategic emerging industries at home.The Chinese government will guido the development of high-tech industries such as wind and solar power equipment manufacturing as China rushed to build a low-carbon economy.In December 2009,Chinese Premier Wen Jiabao listed seven high-tech emerging industries as new energy,energy-saving and environmental protection,electric vehicles,new materials,information industry,new medicine and pharmacology,as well as biological breeding.

  7. Dynamic Feedback Controlling Chaos in Current-Mode Boost Converter

    Institute of Scientific and Technical Information of China (English)

    LU Wei-Guo; ZHOU Luo-Wei; LUO Quan-Ming

    2007-01-01

    A method for the control of chaos in the current-mode boost converter is presented by using the first-order dynamic feedback control. The feedback part consists of a resistance and a capacitance in series. The system to be controlled is treated as a third-order model, and then the discrete mapping model is obtained by using the data-sampling method. By analysing the position of the maximum norm eigenvalue, the stable range of feedback gain is ascertained out and its optimization is also carried out. Finally, the results of simulation and experiment confirm the correctness of the theoretical analysis and the validity of the proposed means.

  8. Black brane entropy and hydrodynamics: the boost-invariant case

    OpenAIRE

    Booth, Ivan; Heller, Michal P.; Spalinski, Michal

    2009-01-01

    The framework of slowly evolving horizons is generalized to the case of black branes in asymptotically anti-de Sitter spaces in arbitrary dimensions. The results are used to analyze the behavior of both event and apparent horizons in the gravity dual to boost-invariant flow. These considerations are motivated by the fact that at second order in the gradient expansion the hydrodynamic entropy current in the dual Yang-Mills theory appears to contain an ambiguity. This ambiguity, in the case of ...

  9. Cylindrical array luminescent solar concentrators: performance boosts by geometric effects.

    Science.gov (United States)

    Videira, Jose J H; Bilotti, Emiliano; Chatten, Amanda J

    2016-07-11

    This paper presents an investigation of the geometric effects within a cylindrical array luminescent solar concentrator (LSC). Photon concentration of a cylindrical LSC increases linearly with cylinder length up to 2 metres. Raytrace modelling on the shading effects of circles on their neighbours demonstrates effective incident light trapping in a cylindrical LSC array at angles of incidence between 60-70 degrees. Raytrace modelling with real-world lighting conditions shows optical efficiency boosts when the suns angle of incidence is within this angle range. On certain days, 2 separate times of peak optical efficiency can be attained over the course of sunrise-solar noon. PMID:27410904

  10. Quasi-Y-Source Boost DC–DC Converter

    DEFF Research Database (Denmark)

    Siwakoti, Yam Prasad; Blaabjerg, Frede; Loh, Poh Chiang

    2015-01-01

    In this letter, a new topology called “quasi-Y-source dc-dc converter” is presented. It inherits all the advantages of the original Y-source converter. In addition, the new topology draws a continuous current from the source, which is definitely more appropriate for most renewable sources. It also...... has dc-current-blocking capacitors, which will definitely help to prevent the coupled inductor core from saturation. Experimental testing has proven the validity of the proposed network and its application as a high boost dc-dc converter....

  11. Distributed Generation using Indirect Matrix Converter in Boost Operating Mode

    DEFF Research Database (Denmark)

    Liu, Xiong; Loh, Poh Chiang; Wang, Peng;

    2011-01-01

    Indirect matrix converter (IMC) using two stages configuration is an interesting alternative for ac/ac conversions. In some cases, the ac/ac converter needs boost function, which can't be achieved by traditional IMC due to its limited input-to-output voltage transfer gain 0.866. Alternatively...... power factor and controllable grid-side power factor. In isolated mode, the matrix converter is controlled to supply a three-phase ac voltage and also guarantee sinusoidal input/output waveforms as well as unity input power factor. Simulation and experimental results are provided to validate...... the effectiveness of the control schemes for the proposed matrix converter....

  12. Experimental prototype for PWM – Based Sliding Mode Boost Converter

    Directory of Open Access Journals (Sweden)

    R. A. Abdulhalem

    2011-06-01

    Full Text Available The paper dells with a modified experimental prototype for pulse-width modulation (PWM sliding mode control (SMC applied to a DC-to-DC-boost converter operated in continuous conduction mode (CCM. Experimental results show that the proposed control schme provides good voltage regulation and is suitable for common DC-to-DC conversion purposes. The prototype and its implementation are given in detail. The static and dynamic performances of the The static and dynamic performances of the experimental system are recorded. Experimental results show that the proposed control scheme provides good voltage regulation and is suitable for common DC-to-DC conversion purposes.

  13. Nonlinear Phenomena in Buck-Boost Power Factor Correction Converter

    Directory of Open Access Journals (Sweden)

    Mehrnoosh Vatani

    2013-01-01

    Full Text Available Buck-Boost Power-Factor-Correction (PFC converter with Average-Current-Model (ACM control is a nonlinear circuit because of the multiplier using and large change in the duty cycle, so its stability analysis must be studied by nonlinear model. In this paper double averaging method is used for describing the model of this converter. By this model we would be able to explain the low frequency dynamics of the system and identify stability boundaries according to circuit parameters and also nonlinear phenomena of this converter are detected.

  14. MadMax, or Where Boosted Significances Come From

    CERN Document Server

    Plehn, Tilman; Wiegand, Daniel

    2013-01-01

    In an era of increasingly advanced experimental analysis techniques it is crucial to understand which phase space regions contribute a signal extraction from backgrounds. Based on the Neyman-Pearson lemma we compute the maximum significance for a signal extraction as an integral over phase space regions. We then study to what degree boosted Higgs strategies benefit ZH and ttH searches and which transverse momenta of the Higgs are most promising. We find that Higgs and top taggers are the appropriate tools, but would profit from a targeted optimization towards smaller transverse momenta. MadMax is available as an add-on to Madgraph5.

  15. A Boost Test of Anomalous Diphoton Resonance at the LHC

    CERN Document Server

    Cao, Qing-Hong; Xie, Ke-Pan; Yan, Bin; Zhang, Dong-Ming

    2015-01-01

    The recent observed diphoton resonance around 750 GeV at the LHC Run-2 could be interpreted as a weak singlet scalar. Adapting the approach of effective field theory we argue that the scalar might also decay into $WW$ or $ZZ$ pairs, which are highly boosted and appear as two fat vector-jets in the detector. We demonstrate that the signature of two vector-jets provides a powerful tool to crosscheck the diphoton anomaly and should be explored in the LHC Run-II experiment.

  16. Grid Connected WECS with A Five Level DCMLI using PID Controller

    Directory of Open Access Journals (Sweden)

    G.Balaji

    2014-07-01

    Full Text Available This paper deals with the analysis, modeling and control system for permanent magnet synchronous generator (PMSG based wind turbine connected to the grid. A wind energy conversion using DC-DC Buck- Boost Converter for permanent magnet synchronous generator (PMSG based variable speed wind energy conversion system (WECS has been proposed which is integrated with grid using five-level diode clamped multilevel (DCMLI inverter. In this work the instantaneous values of input side current and voltage of DC-DC buck-boost converter are utilized for implementing the PID controller. The proposed work is verified by the simulation in Powersim.

  17. High Frequency Soft Switching Of PWM Boost Converter Using Auxiliary Resonant Circuit

    OpenAIRE

    C. P. Sai Kiran; M. Vishnu Vardhan

    2014-01-01

    This thesis presents High frequency Soft Switching DC-DC boost Converter. The circuit consists of a general Boost Converter with an additional resonant circuit which has a switch, inductor, capacitor and a diode.In general Boost Converter circuits have snubber circuits where switching losses are dissipated in external passive resistors; which is known as hard switching. As the switching frequency of PWM converters is increased its switching losses and conduction losses also in...

  18. Connection Strings Property on ADO Connection Object

    Institute of Scientific and Technical Information of China (English)

    Girigi Deogratias; Wu Min; Cao Weihua

    2002-01-01

    The connection string property on ADO connection object contains the information used to establish a connection to the data source. The syntax, the keyword of that information must be in specific format. Depending on the type of data you are connecting to, you need either specify an OLEDB provider or use on ODBC driver. The biggest problem, the industries face is the proliferation of data access interfaces, and the complexity of creating,maintaining and programming against them, and the network problem when communicating over the Intranet or the Internet. This paper first provides an in-depth look of the standard arguments supported by ADO connection string; then gives the easier way for understanding the meaning, the utility and the syntax of the connection strings property on ADO connection object, and finally proposes solution to work around the problems due to the connection strings errors.

  19. Modeling and Simulation of Buck-Boost Converter with Voltage Feedback Control

    OpenAIRE

    Zhou Xuelian; He Qiang

    2015-01-01

    In order to design the control system, it is necessary to have an exact model of buck-boost converter. This paper put forward the transfer function model of buck-boost converter by the state-space average method. The open-loop transfer function model of uncompensated system is deduced according to the mathematic model of the buck-boost converter, the controller is designed according to frequency domain. The phase and magnitude margin of the open-loop system of the buck-boost converter with co...

  20. Different Boosting Systems and their Control Strategies for a Spark Ignition Internal Combustion Engine

    Directory of Open Access Journals (Sweden)

    Bolehovský Ondřej

    2016-06-01

    Full Text Available This research uses 1-D simulation in GT-Power for evaluation of boosting systems for a spark ignition engine. Exhaust gas driven (waste-gated turbocharger and mechanical driven (Roots blower boosting systems are assessed in both steady state and transient modes in terms of performance, efficiency, fuel consumption, drivability, energy distribution and other aspects that influence gas exchange phase. Moreover, different boost control strategies, particularly at partial load, are also evaluated. Results of the research are aimed at helping identify an optimal boosting system for standardized or real-world drive cycles.

  1. Average and Small Signal Modeling of Negative-Output KY Boost Converter in CCM Operation

    Directory of Open Access Journals (Sweden)

    Faqiang Wang

    2014-01-01

    Full Text Available Negative-output KY Boost converter, which can obtain the negative output voltage and could be driven easily, is a good topology to overcome traditional Boost and Buck-Boost converters and it is believed that this converter will be widely used in engineering applications in the future. In this study, by using the averaging method and geometrical technique, the average and small signal model of the negative-output KY Boost converter are established. The DC equilibrium point and transfer functions of the system are derived and analyzed. Finally, the effectiveness of the established model and the correctness of the theoretical analysis are confirmed by the circuit experiment.

  2. Attribute-space connectivity and connected filters

    NARCIS (Netherlands)

    Wilkinson, Michael H.F.

    2007-01-01

    In this paper connected operators from mathematical morphology are extended to a wider class of operators, which are based on connectivities in higher dimensional spaces, similar to scale spaces, which will be called attribute-spaces. Though some properties of connected filters are lost, granulometr

  3. Electron and high-dose-rate brachytherapy boost in the conservative treatment of stage I-II breast cancer. First results of the randomized Budapest boost trial

    Energy Technology Data Exchange (ETDEWEB)

    Polgar, C.; Fodor, J. [National Institute of Oncology, Department of Radiotherapy, Budapest (Hungary); Orosz, Z. [National Institute of Oncology, Center of Experimental and Human Tumor Pathology Budapest (HU)] [and others

    2002-11-01

    Background and Aims: To evaluate the effect of electron and high-dose-rate brachytherapy (HDR BT) boost on local tumor control (LTC), side effects and cosmesis after breast-conserving surgery (BCS) in a prospective randomized study. Patients and Methods: 207 women with stage I-II breast cancer who underwent BCS were treated by 50 Gy irradiation to the whole breast and then randomly assigned to receive either a boost to the tumor bed (n=104) or no further radiotherapy (n=103). Boost treatments consisted of either 16 Gy electron irradiation (n=52) or 12-14.25 Gy HDR BT (n=52). Breast cancer-related events, side effects, and cosmetic results were assessed. Results: At a median follow-up of 5.3 years, the crude rate of local recurrence was 6.7% (7/104) with and 15.5% (16/103) without boost. The 5-year probability of LTC, relapse-free survival (RFS), and cancer-specific survival (CSS) was 92.7% vs 84.9% (p=0.049), 76.6% vs 66.2% (p=0.044), and 90.4% vs. 82.1% (p=0.053), respectively. There was no significant difference in LTC between patients treated with electron or HDR BT boost (94.2% vs 91.4%; p=0.74). On multivariate analysis, patient age <40 years (RR: 4.53), positive margin status (RR: 4.17), and high mitotic activity index (RR: 3.60) were found to be significant risk factors for local recurrence. The incidence of grade 2-3 side effects was higher in the boost arm (17.3% vs 7.8%; p=0.03). However, the rate of excellent/good cosmetic results was similar for the two arms (85.6% vs 91.3%; p=0.14). Cosmesis was rated as excellent/good in 88.5% of patients treated with HDR BT and 82.7% of patients with electron boost (p=0.29). Conclusions: Boost dose significantly improves LTC and RFS in patients treated with BCS and radiotherapy. In spite of the higher incidence of late side effects in the boost arm, boost dose is strongly recommended for patients at high risk for local recurrence. Positive or close margin status, high mitotic activity index, and young patient age

  4. Electron and high-dose-rate brachytherapy boost in the conservative treatment of stage I-II breast cancer. First results of the randomized Budapest boost trial

    International Nuclear Information System (INIS)

    Background and Aims: To evaluate the effect of electron and high-dose-rate brachytherapy (HDR BT) boost on local tumor control (LTC), side effects and cosmesis after breast-conserving surgery (BCS) in a prospective randomized study. Patients and Methods: 207 women with stage I-II breast cancer who underwent BCS were treated by 50 Gy irradiation to the whole breast and then randomly assigned to receive either a boost to the tumor bed (n=104) or no further radiotherapy (n=103). Boost treatments consisted of either 16 Gy electron irradiation (n=52) or 12-14.25 Gy HDR BT (n=52). Breast cancer-related events, side effects, and cosmetic results were assessed. Results: At a median follow-up of 5.3 years, the crude rate of local recurrence was 6.7% (7/104) with and 15.5% (16/103) without boost. The 5-year probability of LTC, relapse-free survival (RFS), and cancer-specific survival (CSS) was 92.7% vs 84.9% (p=0.049), 76.6% vs 66.2% (p=0.044), and 90.4% vs. 82.1% (p=0.053), respectively. There was no significant difference in LTC between patients treated with electron or HDR BT boost (94.2% vs 91.4%; p=0.74). On multivariate analysis, patient age <40 years (RR: 4.53), positive margin status (RR: 4.17), and high mitotic activity index (RR: 3.60) were found to be significant risk factors for local recurrence. The incidence of grade 2-3 side effects was higher in the boost arm (17.3% vs 7.8%; p=0.03). However, the rate of excellent/good cosmetic results was similar for the two arms (85.6% vs 91.3%; p=0.14). Cosmesis was rated as excellent/good in 88.5% of patients treated with HDR BT and 82.7% of patients with electron boost (p=0.29). Conclusions: Boost dose significantly improves LTC and RFS in patients treated with BCS and radiotherapy. In spite of the higher incidence of late side effects in the boost arm, boost dose is strongly recommended for patients at high risk for local recurrence. Positive or close margin status, high mitotic activity index, and young patient age

  5. FINDING AND RECOMMENDATIONS ON READING ALOUD ERRORS TO BILINGUAL TURKISH STUDENT (ROMANIA SAMPLE - İKİ DİLLİ TÜRK ÇOCUKLARININ SESLİ OKUMA HATALARI ÜZERİNE TESPİT VE ÖNERİLER (ROMANYA ÖRNEĞİ

    Directory of Open Access Journals (Sweden)

    Mehmet KARA

    2015-08-01

    Full Text Available The main aim of this study is to identify reading aloud errors of the bilingual Turkish children while teaching standard Turkish to them and to show the methods and techniques that can be used to correct these reading aloud errors. Due to the contribution of reading aloud to multiple language skills, detecting of errors made during reading aloud and their eliminations will contribute greatly to the development of reading, listening, speaking and writing skills. In this study, 16 different reading aloud errors were detected. These errors were 16 different reading aloud errors under two main headings as pronunciation and posture. They were repeating words, repeating syllables, eliding syllables, eliding sounds, elision, pronunciation, crosstalk, spelling mistakes, uttering failure, adding sounds, adding syllables, adding words, uncontrolled breathing, arrest, tracking with fingers, leaning while reading. In this study, the text “Olive Cube” with 812 words was designated as an application text on the basis of students’ proficiency levels. The students were made to read aloud the text and the data was collected by video recording while the students were reading. This study is an observational, descriptive model of qualitative research built upon video recording, video decoding and observation. The data was obtained according to proficiency levels, genders and marriage types. As a result of the study, totally 4689 errors were recorded in all of the proficiency classes. In all of the classes most errors were made in repeating words. It was shown that as the students’ levels increased, their error numbers decreased. When we measured all the reading aloud errors in all the proficiency classes according to students’ genders, it was emerged that the average errors that the female students made was lower than those of male students. Female students did all errors less than male students. When we evaluated the students’ reading aloud errors

  6. A TEG Efficiency Booster with Buck-Boost Conversion

    Science.gov (United States)

    Wu, Hongfei; Sun, Kai; Zhang, Junjun; Xing, Yan

    2013-07-01

    A thermoelectric generator (TEG) efficiency booster with buck-boost conversion and power management is proposed as a TEG battery power conditioner suitable for a wide TEG output voltage range. An inverse-coupled inductor is employed in the buck-boost converter, which is used to achieve smooth current with low ripple on both the TEG and battery sides. Furthermore, benefiting from the magnetic flux counteraction of the two windings on the coupled inductor, the core size and power losses of the filter inductor are reduced, which can achieve both high efficiency and high power density. A power management strategy is proposed for this power conditioning system, which involves maximum power point tracking (MPPT), battery voltage control, and battery current control. A control method is employed to ensure smooth switching among different working modes. A modified MPPT control algorithm with improved dynamic and steady-state characteristics is presented and applied to the TEG battery power conditioning system to maximize energy harvesting. A 500-W prototype has been built, and experimental tests carried out on it. The power efficiency of the prototype at full load is higher than 96%, and peak efficiency of 99% is attained.

  7. (In)direct Detection of Boosted Dark Matter

    CERN Document Server

    Agashe, Kaustubh; Necib, Lina; Thaler, Jesse

    2014-01-01

    We initiate the study of novel thermal dark matter (DM) scenarios where present-day annihilation of DM in the galactic center produces boosted stable particles in the dark sector. These stable particles are typically a subdominant DM component, but because they are produced with a large Lorentz boost in this process, they can be detected in large volume terrestrial experiments via neutral-current-like interactions with electrons or nuclei. This novel DM signal thus combines the production mechanism associated with indirect detection experiments (i.e. galactic DM annihilation) with the detection mechanism associated with direct detection experiments (i.e. DM scattering off terrestrial targets). Such processes are generically present in multi-component DM scenarios or those with non-minimal DM stabilization symmetries. As a proof of concept, we present a model of two-component thermal relic DM, where the dominant heavy DM species has no tree-level interactions with the standard model and thus largely evades dir...

  8. Angular observables for spin discrimination in boosted diboson final states

    CERN Document Server

    Buschmann, Malte

    2016-01-01

    We investigate the prospects for spin determination of a heavy diboson resonance using angular observables. Focusing in particular on boosted fully hadronic final states, we detail both the differences in signal efficiencies and distortions of differential distributions resulting from various jet substructure techniques. We treat the 2 TeV diboson excess as a case study, but our results are generally applicable to any future discovery in the diboson channel. Scrutinizing ATLAS and CMS analyses at 8 TeV and 13 TeV, we find that the specific cuts employed in these analyses have a tremendous impact on the discrimination power between different signal hypotheses. We discuss modified cuts that can offer a significant boost to spin sensitivity in a post-discovery era. Even without altered cuts, we show that CMS, and partly also ATLAS, will be able to distinguish between spin 0, 1, or 2 new physics diboson resonances at the $2\\sigma$ level with 30 fb$^{-1}$ of 13 TeV data, for our 2 TeV case study.

  9. Boosting Nodes for Improving the Spread of Influence

    CERN Document Server

    Liontis, Konstantinos

    2016-01-01

    Information diffusion in networks has received a lot of recent attention. Most previous work addresses the influence maximization problem of selecting an appropriate set of seed nodes to initiate the diffusion process so that the largest number of nodes is reached. Since the seed selection problem is NP hard, most solutions are sub-optimal. Furthermore, there may be settings in which the seed nodes are predetermined. Thus, a natural question that arise is: given a set of seed nodes, can we select a small set of nodes such that if we improve their reaction to the diffusion process, the largest increase in diffusion spread is achieved? We call this problem, the boost set selection problem. In this paper, we formalize this problem, study its complexity and propose appropriate algorithms. We also evaluate the effect of boosting in a number of real networks and report the increase of influence spread achieved for different seed sets, time limits in the diffusion process and other diffusion parameters.

  10. A boosted optimal linear learner for retinal vessel segmentation

    Science.gov (United States)

    Poletti, E.; Grisan, E.

    2014-03-01

    Ocular fundus images provide important information about retinal degeneration, which may be related to acute pathologies or to early signs of systemic diseases. An automatic and quantitative assessment of vessel morphological features, such as diameters and tortuosity, can improve clinical diagnosis and evaluation of retinopathy. At variance with available methods, we propose a data-driven approach, in which the system learns a set of optimal discriminative convolution kernels (linear learner). The set is progressively built based on an ADA-boost sample weighting scheme, providing seamless integration between linear learner estimation and classification. In order to capture the vessel appearance changes at different scales, the kernels are estimated on a pyramidal decomposition of the training samples. The set is employed as a rotating bank of matched filters, whose response is used by the boosted linear classifier to provide a classification of each image pixel into the two classes of interest (vessel/background). We tested the approach fundus images available from the DRIVE dataset. We show that the segmentation performance yields an accuracy of 0.94.

  11. Angular observables for spin discrimination in boosted diboson final states

    Science.gov (United States)

    Buschmann, Malte; Yu, Felix

    2016-09-01

    We investigate the prospects for spin determination of a heavy diboson resonance using angular observables. Focusing in particular on boosted fully hadronic final states, we detail both the differences in signal efficiencies and distortions of differential distributions resulting from various jet substructure techniques. We treat the 2 TeV diboson excess as a case study, but our results are generally applicable to any future discovery in the diboson channel. Scrutinizing ATLAS and CMS analyses at 8 TeV and 13 TeV, we find that the specific cuts employed in these analyses have a tremendous impact on the discrimination power between different signal hypotheses. We discuss modified cuts that can offer a significant boost to spin sensitivity in a post-discovery era. Even without altered cuts, we show that CMS, and partly also ATLAS, will be able to distinguish between spin 0, 1, or 2 new physics diboson resonances at the 2 σ level with 30 fb-1 of 13 TeV data, for our 2 TeV case study.

  12. Boosted Dark Matter Signals Uplifted with Self-Interaction

    CERN Document Server

    Kong, Kyoungchul; Park, Jong-Chul

    2015-01-01

    We explore detection prospects of a non-standard dark sector in the context of boosted dark matter. We focus on a scenario with two dark matter particles of a large mass difference, where the heavier candidate is secluded and interacts with the standard model particles only at loops, escaping existing direct and indirect detection bounds. Yet its pair annihilation in the galactic center or in the Sun may produce boosted stable particles, which could be detected as visible Cherenkov light in large volume neutrino detectors. In such models with multiple candidates, self-interaction of dark matter particles is naturally utilized in the {\\it assisted freeze-out} mechanism and is corroborated by various cosmological studies such as N-body simulations of structure formation, observations of dwarf galaxies, and the small scale problem. We show that self-interaction of the secluded (heavier) dark matter greatly enhances the capture rate in the Sun and results in promising signals at current and future experiments. We...

  13. Intrinsic physical properties and Doppler boosting effects in LSI+61303

    CERN Document Server

    Massi, M

    2014-01-01

    Our aim is to show how variable Doppler boosting of an intrinsically variable jet can explain the long-term modulation of 1667 \\pm 8 days observed in the radio emission of LSI+61303. The physical scenario is that of a conical, magnetized plasma jet having a periodical (P1) increase of relativistic particles, Nrel, at a specific orbital phase, as predicted by accretion in the eccentric orbit of LSI+61303. Jet precession (P2) changes the angle, eta, between jet axis and line of sight, thereby inducing variable Doppler boosting. The problem is defined in spherical geometry, and the optical depth through the precessing jet is calculated by taking into account that the plasma is stratified along the jet axis. The synchrotron emission of such a jet was calculated and we fitted the resulting flux density Smodel(t) to the observed flux density obtained during a 6.5-year monitoring of LSI+61303 by the Green Bank radio interferometer. Our physical model for the system LSI+61303 is not only able to reproduce the long-te...

  14. Engaging Students through Blogs: Using Blogs to Boost a Course Experience

    Directory of Open Access Journals (Sweden)

    Zuhrieh A Shana

    2015-02-01

    Full Text Available Globalization is irreversible and the Internet is increasingly used to connect people and share information worldwide. The proliferation of digital information allows us to make choices about how we gather information and use technology to enhance learning. This is especially true in an academic environment, where the Internet is often used as a tool to facilitate deeper learning. The focus of this study is to investigate whether and how to use blogs to boost student learning in a traditional learning environment where lecture based (didactic instructional practices still prevailing. This paper will also look at Al-Ain University of Science and Technology (AAU student perceptions of the benefits of blogs for enhancing college learning. To explore these issues, Blogging was introduced to students in the Internet Technology class. A combination of one hundred and ninety-nine graduate and undergraduate AAU students answered an online questionnaire exploring their perceptions of blogs as a learning tool. Quantitative and qualitative data was also collected through open-ended questionnaires, student journals and reports, and end-of-class e-portfolios. All statistical analyses were carried out with SPSS. Results indicate that blogs have the potential to empower and enhance student learning. Student response to using blogs in the course has been overwhelmingly positive.

  15. Highly efficient integrated rectifier and voltage boosting circuits for energy harvesting applications

    Directory of Open Access Journals (Sweden)

    D. Maurath

    2008-05-01

    Full Text Available This paper presents novel circuit concepts for integrated rectifiers and voltage converting interfaces for energy harvesting micro-generators. In the context of energy harvesting, usually only small voltages are supplied by vibration-driven generators. Therefore, rectification with minimum voltage losses and low reverse currents is an important issue. This is realized by novel integrated rectifiers which were fabricated and are presented in this article. Additionally, there is a crucial need for dynamic load adaptation as well as voltage up-conversion. A circuit concept is presented, which is able to obtain both requirements. This generator interface adapts its input impedance for an optimal energy transfer efficiency. Furthermore, this generator interface provides implicit voltage up-conversion, whereas the generator output energy is stored on a buffer, which is connected to the output of the voltage converting interface. As simulations express, this fully integrated converter is able to boost ac-voltages greater than |0.35 V| to an output dc-voltage of 2.0 V–2.5 V. Thereby, high harvesting efficiencies above 80% are possible within the entire operational range.

  16. An experimental study on a training support system utilizing trainee's eye gaze point and think aloud protocol for diagnosing nuclear power plant anomalies

    International Nuclear Information System (INIS)

    An experimental system has been developed for aiming at supporting the simulator training of diagnosis nuclear power plant anomaly, where an expert provides the instructions to a trainee by his/her own educational and experienced point of view. This system has several characteristics as follows: (1) the expert can provide the instruction through the local area network or the Internet, (2) the training task is the detection of the primary cause of plant anomaly, which is not including the plant operation but requires only thinking, and (3) the system can automatically detects the trainee's view-point and think aloud protocols and provide these two types of information to the expert in real time for supporting his/her instruction. A laboratory experiment using this system was conducted, where an expert, who had really engaged in plant operation as a chief operator, was employed as the instructor for novice students. As the result of analyzing the experimental data, it was found that the two types of information, trainee's viewpoints and his verbal protocols, have some potential of effectiveness for supporting the instructor to estimate the trainees diagnostic thinking process and provide the instruction. (author)

  17. The Effect of Three Kinds of Reading Strategies on EFL Learners’ Reading Comprehension and Gender Difference Using Think-aloud Protocol

    Directory of Open Access Journals (Sweden)

    Ali Fathi Karizak

    2016-09-01

    Full Text Available Reading comprehension strategy instruction is a powerful tool in teaching context. The present study examines the effect of teaching three kinds of reading strategies on L2 learners’ reading comprehension ability as well as identifying the gender role in this intervention. This quasi experimental study was carried out on 100 Iranian EFL students who were chosen on the basis of a convenient sampling procedure. These participants were divided into two groups of experimental and control.  50 students (experimental group were taught to use three reading comprehension strategies while reading English texts over 16 sessions, whereas the other 50 students (control group were taught reading comprehension traditionally. The results of the study revealed significant effect of reading strategies application on L2 learners’ reading comprehension ability. It also showed that not only male learners employ reading strategies more than their female counterparts, but also male learners had higher reading comprehension performance in comparison to their female counterparts. Thus, it seems that training of reading strategy raised students' awareness towards these strategies and could encourage some learners to use them; which in turn could improve the students' reading comprehension skill.  Keywords: Reading; Strategy; Reading strategies; Reading comprehension; Think-aloud protocol

  18. All-SiC Inductively Coupled Charger with Integrated Plug-in and Boost Functionalities for PEV Applications

    Energy Technology Data Exchange (ETDEWEB)

    Chinthavali, Madhu Sudhan [ORNL; Campbell, Steven L [ORNL; Tolbert, Leon M [ORNL

    2016-01-01

    So far, vehicular power electronics integration is limited to the integration of on-board battery chargers (OBC) into the traction drive system and sometimes to the accessory dc/dc converters in plug-in electric vehicles (PEV). These integration approaches do not provide isolation from the grid although it is an important feature that is required for user interface systems that have grid connections. This is therefore a major limitation that needs to be addressed along with the integrated functionality. Furthermore, there is no previous study that proposes the integration of wireless charger with the other on-board components. This study features a unique way of combining the wired and wireless charging functionalities with vehicle side boost converter integration and maintaining the isolation to provide the best solution to the plug-in electric vehicle users. The new topology is additionally compared with commercially available OBC systems from manufacturers.

  19. Minimum cost connection networks

    DEFF Research Database (Denmark)

    Hougaard, Jens Leth; Tvede, Mich

    . We use three axioms to characterize allocation rules that truthfully implement cost minimizing networks satisfying all connection demands in a game where: (1) a central planner announces an allocation rule and a cost estimation rule; (2) every agent reports her own connection demand as well as all...... connection costs; and, (3) the central planner selects a cost minimizing network satisfying reported connection demands based on estimated connection costs and allocates true connection costs of the selected network.......In the present paper we consider the allocation of cost in connection networks. Agents have connection demands in form of pairs of locations they want to be connected. Connections between locations are costly to build. The problem is to allocate costs of networks satisfying all connection demands...

  20. Long-term outcome and toxicity of hypofractionated stereotactic body radiotherapy as a boost treatment for head and neck cancer: the importance of boost volume assessment

    OpenAIRE

    Lee, Dong Soo; Kim, Yeon Sil; Cheon, Jae Seok; Song, Jin Ho; SON, Seok Hyun; Jang, Ji Sun; Kang, Young Nam; Kang, Jing Hyoung; Jung, So Lyoung; Yoo, Ie Ryung; Jang, Hong Seok

    2012-01-01

    Background The aim of this study was to report the long-term clinical outcomes of patients who received stereotactic body radiotherapy (SBRT) as a boost treatment for head and neck cancer. Materials and methods Between March 2004 and July 2007, 26 patients with locally advanced, medically inoperable head and neck cancer or gross residual tumors in close proximity to critical structures following head and neck surgery were treated with SBRT as a boost treatment. All patients were initially tre...

  1. Long-term outcome and toxicity of hypofractionated stereotactic body radiotherapy as a boost treatment for head and neck cancer: the importance of boost volume assessment

    OpenAIRE

    Lee Dong; Kim Yeon; Cheon Jae; Song Jin; Son Seok; Jang Ji; Kang Young; Kang Jing; Jung So; Yoo Ie; Jang Hong

    2012-01-01

    Abstract Background The aim of this study was to report the long-term clinical outcomes of patients who received stereotactic body radiotherapy (SBRT) as a boost treatment for head and neck cancer. Materials and methods Between March 2004 and July 2007, 26 patients with locally advanced, medically inoperable head and neck cancer or gross residual tumors in close proximity to critical structures following head and neck surgery were treated with SBRT as a boost treatment. All patients were init...

  2. Whole breast and excision cavity radiotherapy plan comparison: Conformal radiotherapy with sequential boost versus intensity-modulated radiation therapy with a simultaneously integrated boost

    OpenAIRE

    Small, Katherine; Kelly, Chris; Beldham-Collins, Rachael; Gebski, Val

    2013-01-01

    Introduction A comparative study was conducted comparing the difference between (1) conformal radiotherapy (CRT) to the whole breast with sequential boost excision cavity plans and (2) intensity-modulated radiation therapy (IMRT) to the whole breast with simultaneously integrated boost to the excision cavity. The computed tomography (CT) data sets of 25 breast cancer patients were used and the results analysed to determine if either planning method produced superior plans. Methods CT data set...

  3. Boosted searches for new physics at the LHC

    International Nuclear Information System (INIS)

    During the first run of the LHC, no apparent signs of new physics beyond the Standard Model were discovered, but rather the Standard Model-like properties of the Higgs particle confirmed. Therefore, new and powerful methods are needed to disclose the traces of new physics, which is expected to be at the TeV scale in order to solve the hierarchy problem. In this thesis, we propose two complementary strategies for the quest for new physics at the LHC. First, we show how a very boosted Higgs in association with a hard jet can be used to determine the important top Yukawa coupling in gluon fusion. In the inclusive gluon fusion process this is not feasible since possible deviations from its Standard Model value are combined and can even cancel with the effective Higgs-gluon interaction mediated by new top partners. This cancellation is motivated within minimal composite Higgs models but also in certain regions of the MSSM parameter space and can lead to a Standard Model-like inclusive cross section that allows no conclusions on the mass spectrum of the new physics. We work out in detail how this degeneracy can be broken in the boosted Higgs channel and find that even in the worst case scenario with a Standard Model-like inclusive cross section, the top Yukawa coupling can be constrained to 0.8-1.3 times its Standard Model value at 95% CL with an integrated luminosity of 3 000 fb-1. The second strategy is targeted at direct stop and sbottom searches in the fully hadronic top decay channel. Since the stop, sbottom and neutralino masses are unknown, very different event shapes are imaginable, ranging from unboosted top quarks and low missing energy to highly boosted top quarks and large missing energy in the final state. In order to cover a wide range of possible event shapes and consequently stop, sbottom, and neutralino masses, we combine several top taggers based on jet substructure techniques to obtain a scale invariant search strategy. The performance of this approach

  4. 一种多路输入高升压Boost变换器%High Step-up Boost Converter with Multiple-input

    Institute of Scientific and Technical Information of China (English)

    罗全明; 邾玢鑫; 周雒维; 汪洋

    2012-01-01

    Directed towards problems that there are too many photovoltaic modules and the output voltages of them are relative low in the typical photovoltaic grid-connected power system,a non-isolated high step-up Boost converter with multiple-input was proposed in this paper.Firstly,the derivation of the converter with dual input was presented and its operation principle and steady state performance were analyzed in detail.Secondly,the n-input high step-up Boost converter made up of n Boost cells was deduced.Finally,an experimental prototype rated 100 W was built and the experimental results were given.The result has showed that: First,If input voltage balancing,the voltage gain is n times of the basic Boost converter,where n is the number of input port.Second,output voltage can be controlled without more control than basic Boost converter.Third,the voltage stress is lower than basic Boost converter and lower voltage MOSFET can be used,and the converter efficiency can be increased further.%针对光伏发电系统模块多、输出电压低等问题,提出了一种多路输入高升压Boost变换器。首先分析了2路输入高升压Boost变换器的工作原理及性能特点,然后通过拓扑推演,得到了n路输入高升压Boost变换器。在此基础上搭建了输出功率为100 W的实验样机,实验结果表明:n路输入电压平衡时,输出电压与输入电压之比是Boost变换器的n倍;控制简单,无论各个输入电压源电压相等与否,均可以通过一套控制系统实现输出电压恒定;开关器件电压应力低,可以选择额定电压低的器件,有利于提高变换器效率。

  5. Multiclass Boosting with Adaptive Group-Based kNN and Its Application in Text Categorization

    Directory of Open Access Journals (Sweden)

    Lei La

    2012-01-01

    Full Text Available AdaBoost is an excellent committee-based tool for classification. However, its effectiveness and efficiency in multiclass categorization face the challenges from methods based on support vector machine (SVM, neural networks (NN, naïve Bayes, and k-nearest neighbor (kNN. This paper uses a novel multi-class AdaBoost algorithm to avoid reducing the multi-class classification problem to multiple two-class classification problems. This novel method is more effective. In addition, it keeps the accuracy advantage of existing AdaBoost. An adaptive group-based kNN method is proposed in this paper to build more accurate weak classifiers and in this way control the number of basis classifiers in an acceptable range. To further enhance the performance, weak classifiers are combined into a strong classifier through a double iterative weighted way and construct an adaptive group-based kNN boosting algorithm (AGkNN-AdaBoost. We implement AGkNN-AdaBoost in a Chinese text categorization system. Experimental results showed that the classification algorithm proposed in this paper has better performance both in precision and recall than many other text categorization methods including traditional AdaBoost. In addition, the processing speed is significantly enhanced than original AdaBoost and many other classic categorization algorithms.

  6. Buck-Boost Current-Source Inverters With Diode-Inductor Network

    DEFF Research Database (Denmark)

    Gao, Feng; Liang, Chao; Loh, Poh Chiang;

    2009-01-01

    compared with other recently reported buck-boost CSIs. For controlling the proposed CSIs, two modulation schemes are designed for achieving either optimized harmonic performance or minimized commutation count without influencing the inverter current buck-boost gain. These theoretical findings were...

  7. The simultaneous boost technique; The concept of relative normalized total dose

    Energy Technology Data Exchange (ETDEWEB)

    Lebesque, J.V.; Keus, R.B. (Nederlands Kanker Inst. ' Antoni van Leeuwenhoekhuis' , Amsterdam (Netherlands))

    1991-09-01

    Simultaneous boost technique in radiotherapy consists of delivering the boost treatment (additional doses to reduced volumes) simultaneously with the basic (large-field) treatment for all treatment sessions. Both the dose per fraction delivered by basic-treatment fields and by boost-treatment fields have to be reduced to end up with the same total dose in boost volume as in the original schedule, where basic treatment preceded boost treatment. These dose reductions and corresponding weighting factors have been calculated using the linear-quadratic (LQ) model and the concept of Normalized Total Dose (NTD). Relative NTD distributions were computed to evaluate the dose distributions resulting for the simultaneous boost technique with respect to acute and late normal tissue damage and tumor control. For the example of treatment of prostate cancer the weighting factors were calculated on basis of NTD for late normal tissue damage. For treatment of oropharyngeal cancer NTD for acute and normal tissue damage was used to determine the weighting factors. In this last example a theoretical sparing of late normal tissue damage can be demonstrated. Another advantage of simultaneous boost technique is that megavoltage images of the large basic-treatment fields facilitates the determination of the position of the patient with respect to the small boost-treatment fields. (author). 42 refs., 8 figs.

  8. Three-dimensional conformal simultaneously integrated boost technique for breast-conserving radiotherapy

    NARCIS (Netherlands)

    van der Laan, Hans Paul; Dolsma, Wil V; Maduro, John H; Korevaar, Erik W; Hollander, Miranda; Langendijk, Johannes A

    2007-01-01

    PURPOSE: To compare the target coverage and normal tissue dose with the simultaneously integrated boost (SIB) and the sequential boost technique in breast cancer, and to evaluate the incidence of acute skin toxicity in patients treated with the SIB technique. METHODS AND MATERIALS: Thirty patients w

  9. Improvement of the systemic prime/oral boost strategy for systemic and local responses.

    NARCIS (Netherlands)

    Lauterslager, T.G.M.; Stok, W.; Hilgers, L.A.T.

    2003-01-01

    This paper describes oral boost immunisations of primed animals as an alternative oral vaccination strategy. Mice were primed orally (PO), intranasally (IN), subcutaneously (SC), or intraperitoneally (IP) with ovalbumin (OVA) with or without adjuvant. Boost immunisations were given orally with or wi

  10. Y-Source Boost DC/DC Converter for Distributed Generation

    DEFF Research Database (Denmark)

    Siwakoti, Yam P.; Loh, Poh Chiang; Blaabjerg, Frede;

    2015-01-01

    This paper introduces a versatile Y-source boost dc/dc converter intended for distributed power generation, where high gain is often demanded. The proposed converter uses a Y-source impedance network realized with a tightly coupled three-winding inductor for high voltage boosting that is presently...

  11. Cost-Sensitive Boosting: Fitting an Additive Asymmetric Logistic Regression Model

    Science.gov (United States)

    Li, Qiu-Jie; Mao, Yao-Bin; Wang, Zhi-Quan; Xiang, Wen-Bo

    Conventional machine learning algorithms like boosting tend to equally treat misclassification errors that are not adequate to process certain cost-sensitive classification problems such as object detection. Although many cost-sensitive extensions of boosting by directly modifying the weighting strategy of correspond original algorithms have been proposed and reported, they are heuristic in nature and only proved effective by empirical results but lack sound theoretical analysis. This paper develops a framework from a statistical insight that can embody almost all existing cost-sensitive boosting algorithms: fitting an additive asymmetric logistic regression model by stage-wise optimization of certain criterions. Four cost-sensitive versions of boosting algorithms are derived, namely CSDA, CSRA, CSGA and CSLB which respectively correspond to Discrete AdaBoost, Real AdaBoost, Gentle AdaBoost and LogitBoost. Experimental results on the application of face detection have shown the effectiveness of the proposed learning framework in the reduction of the cumulative misclassification cost.

  12. Factors associated with patient-reported cosmetic outcome in the Young Boost Breast Trial

    NARCIS (Netherlands)

    Brouwers, Patricia J. A. M.; van Werkhoven, Erik; Bartelink, Harry; Fourquet, Alain; Lemanski, Claire; van Loon, Judith; Maduro, John H.; Russell, Nicola S.; Scheijmans, Luc J. E. E.; Schinagl, Dominic A. X.; Westenberg, Antonia H.; Poortmans, Philip; Boersma, Liesbeth J.

    2016-01-01

    Purpose: To investigate which factors are related to patient reported cosmetic outcome (PRCO) after breast conserving therapy. Methods: From 2004 to 2011, 2421 cT1-2N0-2a breast cancer patients were randomised in the Young Boost Trial between a 16 and a 26 Gy boost to the tumour bed. Cosmesis was sc

  13. Topological Design and Modulation Strategy for Buck-Boost Three-Level Inverters

    DEFF Research Database (Denmark)

    Gao, Feng; Loh, Poh Chiang; Teodorescu, Remus;

    2009-01-01

    can perform distinct five-level line voltage and three-level phase voltage switching by simply controlling the active switches located in the designed voltage boost section of the circuits. As a cost saving option, one active switch can further be removed from the voltage boost section of the circuits...

  14. 14 CFR 27.695 - Power boost and power-operated control system.

    Science.gov (United States)

    2010-01-01

    ... system. 27.695 Section 27.695 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Systems § 27.695 Power boost and power-operated control system. (a) If a power boost or power-operated control system is used, an alternate system must be immediately available that allows continued...

  15. 14 CFR 29.695 - Power boost and power-operated control system.

    Science.gov (United States)

    2010-01-01

    ... system. 29.695 Section 29.695 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Systems § 29.695 Power boost and power-operated control system. (a) If a power boost or power-operated control system is used, an alternate system must be immediately available that allows continued...

  16. Boosting multi-features with prior knowledge for mini unmanned helicopter landmark detection

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Without sufficient real training data, the data driven classification algorithms based on boosting method cannot solely be utilized to applications such as the mini unmanned helicopter landmark image detection. In this paper, we propose an approach which uses a boosting algorithm with the prior knowledge for the mini unmanned helicopter landmark image detection. The stage forward stagewise additive model of boosting is analyzed, and the approach how to combine it with the prior knowledge model is presented. The approach is then applied to landmark image detection, where the multi-features are boosted to solve a series of problems, such as rotation, noises affected, etc. Results of real flight experiments demonstrate that for small training examples the boosted learning system using prior knowledge is dramatically better than the one driven by data only.

  17. A mechatronic power boosting design for piezoelectric generators

    Science.gov (United States)

    Liu, Haili; Liang, Junrui; Ge, Cong

    2015-10-01

    It was shown that the piezoelectric power generation can be boosted by using the synchronized switch power conditioning circuits. This letter reports a self-powered and self-sensing mechatronic design in substitute of the auxiliary electronics towards a compact and universal synchronized switch solution. The design criteria are derived based on the conceptual waveforms and a two-degree-of-freedom analytical model. Experimental result shows that, compared to the standard bridge rectifier interface, the mechatronic design leads to an extra 111% increase of generated power from the prototyped piezoelectric generator under the same deflection magnitude excitation. The proposed design has introduced a valuable physical insight of electromechanical synergy towards the improvement of piezoelectric power generation.

  18. Boosting magnetic reconnection by viscosity and thermal conduction

    Science.gov (United States)

    Minoshima, Takashi; Miyoshi, Takahiro; Imada, Shinsuke

    2016-07-01

    Nonlinear evolution of magnetic reconnection is investigated by means of magnetohydrodynamic simulations including uniform resistivity, uniform viscosity, and anisotropic thermal conduction. When viscosity exceeds resistivity (the magnetic Prandtl number P r m > 1 ), the viscous dissipation dominates outflow dynamics and leads to the decrease in the plasma density inside a current sheet. The low-density current sheet supports the excitation of the vortex. The thickness of the vortex is broader than that of the current for P r m > 1 . The broader vortex flow more efficiently carries the upstream magnetic flux toward the reconnection region, and consequently, boosts the reconnection. The reconnection rate increases with viscosity provided that thermal conduction is fast enough to take away the thermal energy increased by the viscous dissipation (the fluid Prandtl number Pr < 1). The result suggests the need to control the Prandtl numbers for the reconnection against the conventional resistive model.

  19. Mutual boosting of the saturation scales in colliding nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Kopeliovich, B.Z., E-mail: bzk@mpi-hd.mpg.d [Departamento de Fisica, Universidad Tecnica Federico Santa Maria, Instituto de Estudios Avanzados en Ciencias e Ingenieria, Centro Cientifico-Tecnologico de Valparaiso, Casilla 110-V, Valparaiso (Chile); Institut fuer Theoretische Physik der Universitaet, Philosophenweg 19, 69120 Heidelberg (Germany); Pirner, H.J. [Institut fuer Theoretische Physik der Universitaet, Philosophenweg 19, 69120 Heidelberg (Germany); Potashnikova, I.K.; Schmidt, Ivan [Departamento de Fisica, Universidad Tecnica Federico Santa Maria, Instituto de Estudios Avanzados en Ciencias e Ingenieria, Centro Cientifico-Tecnologico de Valparaiso, Casilla 110-V, Valparaiso (Chile)

    2011-03-14

    Saturation of small-x gluons in a nucleus, which has the form of transverse momentum broadening of projectile gluons in pA collisions in the nuclear rest frame, leads to a modification of the parton distribution functions in the beam compared with pp collisions. The DGLAP driven gluon distribution turns out to be suppressed at large x, but significantly enhanced at x<<1. This is a high twist effect. In the case of nucleus-nucleus collisions all participating nucleons on both sides get enriched in gluon density at small x, which leads to a further boosting of the saturation scale. We derive reciprocity equations for the saturation scales corresponding to a collision of two nuclei. The solution of these equations for central collisions of two heavy nuclei demonstrate a significant, up to several times, enhancement of Q{sub sA}{sup 2}, in AA compared with pA collisions.

  20. The Dark Matter Annihilation Boost from Low-Temperature Reheating

    CERN Document Server

    Erickcek, Adrienne L

    2015-01-01

    The evolution of the Universe between inflation and the onset of Big Bang Nucleosynthesis is difficult to probe and largely unconstrained. This ignorance profoundly limits our understanding of dark matter: we cannot calculate its thermal relic abundance without knowing when the Universe became radiation dominated. Fortunately, small-scale density perturbations provide a probe of the early Universe that could break this degeneracy. If dark matter is a thermal relic, density perturbations that enter the horizon during an early matter-dominated era grow linearly with the scale factor prior to reheating. The resulting abundance of substructure boosts the annihilation rate by several orders of magnitude, which can compensate for the smaller annihilation cross sections that are required to generate the observed dark matter density in these scenarios. In particular, thermal relics with masses less than a TeV that thermally and kinetically decouple prior to reheating may already be ruled out by Fermi-LAT observations...

  1. Boosting Magnetic Reconnection by Viscosity and Thermal Conduction

    CERN Document Server

    Minoshima, Takashi; Imada, Shinsuke

    2016-01-01

    Nonlinear evolution of magnetic reconnection is investigated by means of magnetohydrodynamic simulations including uniform resistivity, uniform viscosity, and anisotropic thermal conduction. When viscosity exceeds resistivity (the magnetic Prandtl number Prm > 1), the viscous dissipation dominates outflow dynamics and leads to the decrease in the plasma density inside a current sheet. The low-density current sheet supports the excitation of the vortex. The thickness of the vortex is broader than that of the current for Prm > 1. The broader vortex flow more efficiently carries the upstream magnetic flux toward the reconnection region, and consequently boosts the reconnection. The reconnection rate increases with viscosity provided that thermal conduction is fast enough to take away the thermal energy increased by the viscous dissipation (the fluid Prandtl number Pr < 1). The result suggests the need to control the Prandtl numbers for the reconnection against the conventional resistive model.

  2. A mechatronic power boosting design for piezoelectric generators

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Haili; Liang, Junrui, E-mail: liangjr@shanghaitech.edu.cn; Ge, Cong [School of Information Science and Technology, ShanghaiTech University, No. 8 Building, 319 Yueyang Road, Shanghai 200031 (China)

    2015-10-05

    It was shown that the piezoelectric power generation can be boosted by using the synchronized switch power conditioning circuits. This letter reports a self-powered and self-sensing mechatronic design in substitute of the auxiliary electronics towards a compact and universal synchronized switch solution. The design criteria are derived based on the conceptual waveforms and a two-degree-of-freedom analytical model. Experimental result shows that, compared to the standard bridge rectifier interface, the mechatronic design leads to an extra 111% increase of generated power from the prototyped piezoelectric generator under the same deflection magnitude excitation. The proposed design has introduced a valuable physical insight of electromechanical synergy towards the improvement of piezoelectric power generation.

  3. A mechatronic power boosting design for piezoelectric generators

    International Nuclear Information System (INIS)

    It was shown that the piezoelectric power generation can be boosted by using the synchronized switch power conditioning circuits. This letter reports a self-powered and self-sensing mechatronic design in substitute of the auxiliary electronics towards a compact and universal synchronized switch solution. The design criteria are derived based on the conceptual waveforms and a two-degree-of-freedom analytical model. Experimental result shows that, compared to the standard bridge rectifier interface, the mechatronic design leads to an extra 111% increase of generated power from the prototyped piezoelectric generator under the same deflection magnitude excitation. The proposed design has introduced a valuable physical insight of electromechanical synergy towards the improvement of piezoelectric power generation

  4. Boosting Discriminant Learners for Gait Recognition Using MPCA Features

    Directory of Open Access Journals (Sweden)

    Haiping Lu

    2009-01-01

    Full Text Available This paper proposes a boosted linear discriminant analysis (LDA solution on features extracted by the multilinear principal component analysis (MPCA to enhance gait recognition performance. Three-dimensional gait objects are projected in the MPCA space first to obtain low-dimensional tensorial features. Then, lower-dimensional vectorial features are obtained through discriminative feature selection. These feature vectors are then fed into an LDA-style booster, where several regularized and weakened LDA learners work together to produce a strong learner through a novel feature weighting and sampling process. The LDA learner employs a simple nearest-neighbor classifier with a weighted angle distance measure for classification. The experimental results on the NIST/USF “Gait Challenge” data-sets show that the proposed solution has successfully improved the gait recognition performance and outperformed several state-of-the-art gait recognition algorithms.

  5. Defined three-dimensional microenvironments boost induction of pluripotency

    Science.gov (United States)

    Caiazzo, Massimiliano; Okawa, Yuya; Ranga, Adrian; Piersigilli, Alessandra; Tabata, Yoji; Lutolf, Matthias P.

    2016-03-01

    Since the discovery of induced pluripotent stem cells (iPSCs), numerous approaches have been explored to improve the original protocol, which is based on a two-dimensional (2D) cell-culture system. Surprisingly, nothing is known about the effect of a more biologically faithful 3D environment on somatic-cell reprogramming. Here, we report a systematic analysis of how reprogramming of somatic cells occurs within engineered 3D extracellular matrices. By modulating microenvironmental stiffness, degradability and biochemical composition, we have identified a previously unknown role for biophysical effectors in the promotion of iPSC generation. We find that the physical cell confinement imposed by the 3D microenvironment boosts reprogramming through an accelerated mesenchymal-to-epithelial transition and increased epigenetic remodelling. We conclude that 3D microenvironmental signals act synergistically with reprogramming transcription factors to increase somatic plasticity.

  6. Measuring Intuition: Nonconscious Emotional Information Boosts Decision Accuracy and Confidence.

    Science.gov (United States)

    Lufityanto, Galang; Donkin, Chris; Pearson, Joel

    2016-05-01

    The long-held popular notion of intuition has garnered much attention both academically and popularly. Although most people agree that there is such a phenomenon as intuition, involving emotionally charged, rapid, unconscious processes, little compelling evidence supports this notion. Here, we introduce a technique in which subliminal emotional information is presented to subjects while they make fully conscious sensory decisions. Our behavioral and physiological data, along with evidence-accumulator models, show that nonconscious emotional information can boost accuracy and confidence in a concurrent emotion-free decision task, while also speeding up response times. Moreover, these effects were contingent on the specific predictive arrangement of the nonconscious emotional valence and motion direction in the decisional stimulus. A model that simultaneously accumulates evidence from both physiological skin conductance and conscious decisional information provides an accurate description of the data. These findings support the notion that nonconscious emotions can bias concurrent nonemotional behavior-a process of intuition.

  7. Metabolic engineering of resveratrol and other longevity boosting compounds.

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Y; Chen, H; Yu, O

    2010-09-16

    Resveratrol, a compound commonly found in red wine, has attracted many attentions recently. It is a diphenolic natural product accumulated in grapes and a few other species under stress conditions. It possesses a special ability to increase the life span of eukaryotic organisms, ranging from yeast, to fruit fly, to obese mouse. The demand for resveratrol as a food and nutrition supplement has increased significantly in recent years. Extensive work has been carried out to increase the production of resveratrol in plants and microbes. In this review, we will discuss the biosynthetic pathway of resveratrol and engineering methods to heterologously express the pathway in various organisms. We will outline the shortcuts and limitations of common engineering efforts. We will also discuss briefly the features and engineering challenges of other longevity boosting compounds.

  8. Emerging applications for the Peacekeeper Post Boost Vehicle

    Science.gov (United States)

    Blake, Jack

    1992-07-01

    The use of the Peacekeeper Post Boost Vehicle (PBV) is considered for applications beyond its original use as stage IV of the ICBM system. The PBV is described in the context of the Peacekeeper mission, and the axial engine and attitude-control engines are illustrated. The capability of the PBV is found to make the engine appropriate for use as a liquid-plume generator for the Space Pallet Satellite Experiment. The PBV could also be used as a system basis for transporting large payloads into LEO, and a PBV-based platform could remain in orbit to serve as an earth/payload communication link. The PBV offers technologies and capabilities required for such missions as a plume generator, space-experiment module, or as a transfer vehicle for Space Station logistics and resupply.

  9. Searches for New Physics in boosted topologies at ATLAS

    CERN Document Server

    CERN. Geneva

    2016-01-01

    The large increase in collision energy that the LHC reached in Run 2  provides an unprecedented opportunity to search for new physics beyond the Standard Model (SM). Various extensions of the SM predict heavy resonances at the TeV scale, which couple predominantly to the Higgs and electroweak gauge bosons and to top and bottom quarks. At resonance masses well above 1 TeV, these searches face specific challenges and  employ new identification techniques to disentangle the decay products of the boson in highly boosted configurations. This talk will review recent ATLAS Run-2 searches in various possible final states as well as  the dedicated techniques related to the specificity of such event topologies.

  10. Simulation of closed loop controlled boost converter for solar installation

    Directory of Open Access Journals (Sweden)

    Kalirasu Athimulam

    2010-01-01

    Full Text Available With the shortage of the energy and ever increasing of the oil price, research on the renewable and green energy sources, especially the solar arrays and the fuel cells, becomes more and more important. How to achieve high stepup and high efficiency DC/DC converters is the major consideration in the renewable power applications due to the low voltage of PV arrays and fuel cells. In this paper digital simulation of closed loop controlled boost converter for solar installation is presented. Circuit models for open loop and closed loop controlled systems are developed using the blocks of simulink. The simulation results are compared with the theoretical results. This converter has advantages like improved power factor, fast response and reduced hardware. .

  11. Buck-Buck- Boost Regulatr (B3R)

    Science.gov (United States)

    Mourra, Olivier; Fernandez, Arturo; Landstroem, Sven; Tonicello, Ferdinando

    2011-10-01

    In a satellite, the main function of a Power Conditioning Unit (PCU) is to manage the energy coming from several power sources (usually solar arrays and battery) and to deliver it continuously to the users in an appropriate form during the overall mission. The objective of this paper is to present an electronic switching DC-DC converter called Buck-Buck-Boost Regulator (B3R) that could be used as a modular and recurrent solution in a PCU for regulated or un- regulated 28Vsatellite power bus classes. The power conversion stages of the B3R topology are first described. Then theoretical equations and practical tests illustrate how the converter operates in term of power conversion, control loops performances and efficiency. The paper finally provides some examples of single point failure tolerant implementation using the B3R.

  12. Boosted Top Quark Pair Production in Soft Collinear Effective Theory

    CERN Document Server

    Ferroglia, Andrea; Pecjak, Ben D; Yang, Li Lin

    2014-01-01

    We review a Soft Collinear Effective Theory approach to the study of factorization and resummation of QCD effects in top-quark pair production. In particular, we consider differential cross sections such as the top-quark pair invariant mass distribution and the top-quark transverse momentum and rapidity distributions. Furthermore, we focus our attention on the large invariant mass and large transverse momentum kinematic regions, characteristic of boosted top quarks. We discuss the factorization of the differential cross section in the double soft gluon emission and small top-quark mass limit, both in Pair Invariant Mass (PIM) and One Particle Inclusive (1PI) kinematics. The factorization formulas can be employed in order to implement the simultaneous resummation of soft emission and small mass effects up to next-to-next-to-leading logarithmic accuracy. The results are also used to construct improved next-to-next-to-leading order approximations for the differential cross sections.

  13. An update on Shankhpushpi, a cognition-boosting Ayurvedic medicine.

    Science.gov (United States)

    Sethiya, Neeraj Kumar; Nahata, Alok; Mishra, Sri Hari; Dixit, Vinod Kumar

    2009-11-01

    Shankhpushpi is an Ayurvedic drug used for its action on the central nervous system, especially for boosting memory and improving intellect. Quantum of information gained from Ayurvedic and other Sanskrit literature revealed the existence of four different plant species under the name of Shankhpushpi, which is used in various Ayurvedic prescriptions described in ancient texts, singly or in combination with other herbs. The sources comprise of entire herbs with following botanicals viz., Convulvulus pluricaulis Choisy. (Convulvulaceae), Evolvulus alsinoides Linn. (Convulvulaceae), Clitoria ternatea Linn. (Papilionaceae) and Canscora decussata Schult. (Gentianaceae). A review on the available scientific information in terms of pharmacognostical characteristics, chemical constituents, pharmacological activities, preclinical and clinical applications of controversial sources of Shankhpushpi is prepared with a view to review scientific work undertaken on Shankhpushpi. It may provide parameters of differentiation and permit appreciation of variability of drug action by use of different botanical sources. PMID:19912732

  14. Measuring Intuition: Nonconscious Emotional Information Boosts Decision Accuracy and Confidence.

    Science.gov (United States)

    Lufityanto, Galang; Donkin, Chris; Pearson, Joel

    2016-05-01

    The long-held popular notion of intuition has garnered much attention both academically and popularly. Although most people agree that there is such a phenomenon as intuition, involving emotionally charged, rapid, unconscious processes, little compelling evidence supports this notion. Here, we introduce a technique in which subliminal emotional information is presented to subjects while they make fully conscious sensory decisions. Our behavioral and physiological data, along with evidence-accumulator models, show that nonconscious emotional information can boost accuracy and confidence in a concurrent emotion-free decision task, while also speeding up response times. Moreover, these effects were contingent on the specific predictive arrangement of the nonconscious emotional valence and motion direction in the decisional stimulus. A model that simultaneously accumulates evidence from both physiological skin conductance and conscious decisional information provides an accurate description of the data. These findings support the notion that nonconscious emotions can bias concurrent nonemotional behavior-a process of intuition. PMID:27052557

  15. Usefulness of effective field theory for boosted Higgs production

    Energy Technology Data Exchange (ETDEWEB)

    Dawson, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Lewis, I. M. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Zeng, Mao [Stony Brook Univ., Stony Brook, NY (United States)

    2015-04-07

    The Higgs + jet channel at the LHC is sensitive to the effects of new physics both in the total rate and in the transverse momentum distribution at high pT. We examine the production process using an effective field theory (EFT) language and discussing the possibility of determining the nature of the underlying high-scale physics from boosted Higgs production. The effects of heavy color triplet scalars and top partner fermions with TeV scale masses are considered as examples and Higgs-gluon couplings of dimension-5 and dimension-7 are included in the EFT. As a byproduct of our study, we examine the region of validity of the EFT. Dimension-7 contributions in realistic new physics models give effects in the high pT tail of the Higgs signal which are so tiny that they are likely to be unobservable.

  16. Esophageal Cancer Dose Escalation Using a Simultaneous Integrated Boost Technique

    International Nuclear Information System (INIS)

    Purpose: We previously showed that 75% of radiation therapy (RT) failures in patients with unresectable esophageal cancer are in the gross tumor volume (GTV). We performed a planning study to evaluate if a simultaneous integrated boost (SIB) technique could selectively deliver a boost dose of radiation to the GTV in patients with esophageal cancer. Methods and Materials: Treatment plans were generated using four different approaches (two-dimensional conformal radiotherapy [2D-CRT] to 50.4 Gy, 2D-CRT to 64.8 Gy, intensity-modulated RT [IMRT] to 50.4 Gy, and SIB-IMRT to 64.8 Gy) and optimized for 10 patients with distal esophageal cancer. All plans were constructed to deliver the target dose in 28 fractions using heterogeneity corrections. Isodose distributions were evaluated for target coverage and normal tissue exposure. Results: The 50.4 Gy IMRT plan was associated with significant reductions in mean cardiac, pulmonary, and hepatic doses relative to the 50.4 Gy 2D-CRT plan. The 64.8 Gy SIB-IMRT plan produced a 28% increase in GTV dose and comparable normal tissue doses as the 50.4 Gy IMRT plan; compared with the 50.4 Gy 2D-CRT plan, the 64.8 Gy SIB-IMRT produced significant dose reductions to all critical structures (heart, lung, liver, and spinal cord). Conclusions: The use of SIB-IMRT allowed us to selectively increase the dose to the GTV, the area at highest risk of failure, while simultaneously reducing the dose to the normal heart, lung, and liver. Clinical implications warrant systematic evaluation.

  17. Esophageal Cancer Dose Escalation Using a Simultaneous Integrated Boost Technique

    Energy Technology Data Exchange (ETDEWEB)

    Welsh, James, E-mail: jwelsh@mdanderson.org [Department of Radiation Oncology, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States); Palmer, Matthew B. [Department of Radiation Oncology, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States); Ajani, Jaffer A. [Department of Gastrointestinal Medical Oncology, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States); Liao Zhongxing [Department of Radiation Oncology, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States); Swisher, Steven G.; Hofstetter, Wayne L. [Department of Thoracic and Cardiovascular Surgery, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States); Allen, Pamela K.; Settle, Steven H.; Gomez, Daniel; Likhacheva, Anna; Cox, James D.; Komaki, Ritsuko [Department of Radiation Oncology, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States)

    2012-01-01

    Purpose: We previously showed that 75% of radiation therapy (RT) failures in patients with unresectable esophageal cancer are in the gross tumor volume (GTV). We performed a planning study to evaluate if a simultaneous integrated boost (SIB) technique could selectively deliver a boost dose of radiation to the GTV in patients with esophageal cancer. Methods and Materials: Treatment plans were generated using four different approaches (two-dimensional conformal radiotherapy [2D-CRT] to 50.4 Gy, 2D-CRT to 64.8 Gy, intensity-modulated RT [IMRT] to 50.4 Gy, and SIB-IMRT to 64.8 Gy) and optimized for 10 patients with distal esophageal cancer. All plans were constructed to deliver the target dose in 28 fractions using heterogeneity corrections. Isodose distributions were evaluated for target coverage and normal tissue exposure. Results: The 50.4 Gy IMRT plan was associated with significant reductions in mean cardiac, pulmonary, and hepatic doses relative to the 50.4 Gy 2D-CRT plan. The 64.8 Gy SIB-IMRT plan produced a 28% increase in GTV dose and comparable normal tissue doses as the 50.4 Gy IMRT plan; compared with the 50.4 Gy 2D-CRT plan, the 64.8 Gy SIB-IMRT produced significant dose reductions to all critical structures (heart, lung, liver, and spinal cord). Conclusions: The use of SIB-IMRT allowed us to selectively increase the dose to the GTV, the area at highest risk of failure, while simultaneously reducing the dose to the normal heart, lung, and liver. Clinical implications warrant systematic evaluation.

  18. Boosted di-boson from a mixed heavy stop

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, Diptimoy

    2013-12-01

    The lighter mass eigenstate ($\\widetilde{t}_1$) of the two top squarks, the scalar superpartners of the top quark, is extremely difficult to discover if it is almost degenerate with the lightest neutralino ($\\widetilde{\\chi}_1^0$), the lightest and stable supersymmetric particle in the R-parity conserving supersymmetry. The current experimental bound on $\\widetilde{t}_1$ mass in this scenario stands only around 200 GeV. For such a light $\\widetilde{t}_1$, the heavier top squark ($\\widetilde{t}_2$) can also be around the TeV scale. Moreover, the high value of the higgs ($h$) mass prefers the left and right handed top squarks to be highly mixed allowing the possibility of a considerable branching ratio for $\\widetilde{t}_2 \\to \\widetilde{t}_1 h$ and $\\widetilde{t}_2 \\to \\widetilde{t}_1 Z$. In this paper, we explore the above possibility together with the pair production of $\\widetilde{t}_2$ $\\widetilde{t}_2^*$ giving rise to the spectacular di-boson + missing transverse energy final state. For an approximately 1 TeV $\\widetilde{t}_2$ and a few hundred GeV $\\widetilde{t}_1$ the final state particles can be moderately boosted which encourages us to propose a novel search strategy employing the jet substructure technique to tag the boosted $h$ and $Z$. The reconstruction of the $h$ and $Z$ momenta also allows us to construct the stransverse mass $M_{T2}$ providing an additional efficient handle to fight the backgrounds. We show that a 4--5$\\sigma$ signal can be observed at the 14 TeV LHC for $\\sim$ 1 TeV $\\widetilde{t}_2$ with 100 fb$^{-1}$ integrated luminosity.

  19. Comparison of composite prostate radiotherapy plan doses with dependent and independent boost phases.

    Science.gov (United States)

    Narayanasamy, Ganesh; Avila, Gabrielle; Mavroidis, Panayiotis; Papanikolaou, Niko; Gutierrez, Alonso; Baacke, Diana; Shi, Zheng; Stathakis, Sotirios

    2016-09-01

    Prostate cases commonly consist of dual phase planning with a primary plan followed by a boost. Traditionally, the boost phase is planned independently from the primary plan with the risk of generating hot or cold spots in the composite plan. Alternatively, boost phase can be planned taking into account the primary dose. The aim of this study was to compare the composite plans from independently and dependently planned boosts using dosimetric and radiobiological metrics. Ten consecutive prostate patients previously treated at our institution were used to conduct this study on the Raystation™ 4.0 treatment planning system. For each patient, two composite plans were developed: a primary plan with an independently planned boost and a primary plan with a dependently planned boost phase. The primary plan was prescribed to 54 Gy in 30 fractions to the primary planning target volume (PTV1) which includes prostate and seminal vesicles, while the boost phases were prescribed to 24 Gy in 12 fractions to the boost planning target volume (PTV2) that targets only the prostate. PTV coverage, max dose, median dose, target conformity, dose homogeneity, dose to OARs, and probabilities of benefit, injury, and complication-free tumor control (P+) were compared. Statistical significance was tested using either a 2-tailed Student's t-test or Wilcoxon signed-rank test. Dosimetrically, the composite plan with dependent boost phase exhibited smaller hotspots, lower maximum dose to the target without any significant change to normal tissue dose. Radiobiologically, for all but one patient, the percent difference in the P+ values between the two methods was not significant. A large percent difference in P+ value could be attributed to an inferior primary plan. The benefits of considering the dose in primary plan while planning the boost is not significant unless a poor primary plan was achieved.

  20. The modeling and simulation of thermal based modified solid oxide fuel cell (SOFC) for grid-connected systems

    OpenAIRE

    Ayetül Gelen; Tankut Yalcinoz

    2015-01-01

    This paper presents a thermal based modified dynamic model of a Solid Oxide Fuel Cell (SOFC) for grid-connected systems. The proposed fuel cell model involves ohmic, activation and concentration voltage losses, thermal dynamics, methanol reformer, fuel utilization factor and power limiting module. A power conditioning unit (PCU), which consists of a DC-DC boost converter and a DC-AC voltage-source inverter (VSI), their controller, transformer and filter, is designed for grid-connected systems...

  1. Minimum cost connection networks

    DEFF Research Database (Denmark)

    Hougaard, Jens Leth; Tvede, Mich

    2015-01-01

    demands. We use a few axioms to characterize allocation rules that truthfully implement cost minimizing networks satisfying all connection demands in a game where: (1) a central planner announces an allocation rule and a cost estimation rule; (2) every agent reports her own connection demand as well...... as all connection costs; (3) the central planner selects a cost minimizing network satisfying reported connection demands based on the estimated costs; and, (4) the planner allocates the true costs of the selected network. It turns out that an allocation rule satisfies the axioms if and only if relative......In the present paper we consider the allocation of costs in connection networks. Agents have connection demands in form of pairs of locations they want to have connected. Connections between locations are costly to build. The problem is to allocate costs of networks satisfying all connection...

  2. Connecting Marine Uninterruptible Power Systems to Internet of Things

    OpenAIRE

    Sorva, Esko

    2016-01-01

    Internet of Things (IoT) refers to a state of development where the Internet expands to cover physical things and objects in similar manner like it currently connects people using computers and mobile devices. It is predicted, that these new types of Internet users will exceed the number of human users and become the largest group of Internet users and content creators. The anticipated economy boosting impact of IoT is predicted to be comparable to those of the preceding industrialization and...

  3. Grid-connected of photovoltaic module using nonlinear control

    DEFF Research Database (Denmark)

    El Fadil, H.; Giri, F.; Guerrero, Josep M.

    2012-01-01

    The problem of controlling single-phase grid connected photovoltaic (PV) system is considered. The control objective is fourfold: (i) asymptotic stability of the closed loop system, (ii) maximum power point tracking (MPPT) of PV module (iii) tight regulation of the DC bus voltage, and (iv) unity...... power factor (PF) in the grid. A nonlinear controller is developed using the backstepping design technique based on an averaged nonlinear model of the whole controlled system. The model accounts, on the one hand, for the nonlinear dynamics of the underlying boost converter and inverter and, on the other...

  4. A novel sparse boosting method for crater detection in the high resolution planetary image

    Science.gov (United States)

    Wang, Yan; Yang, Gang; Guo, Lei

    2015-09-01

    Impact craters distributed on planetary surface become one of the main barriers during the soft landing of planetary probes. In order to accelerate the crater detection, in this paper, we present a new sparse boosting (SparseBoost) method for automatic detection of sub-kilometer craters. The SparseBoost method integrates an improved sparse kernel density estimator (RSDE-WL1) into the Boost algorithm and the RSDE-WL1 estimator is achieved by introducing weighted l1 penalty term into the reduced set density estimator. An iterative algorithm is proposed to implement the RSDE-WL1. The SparseBoost algorithm has the advantage of fewer selected features and simpler representation of the weak classifiers compared with the Boost algorithm. Our SparseBoost based crater detection method is evaluated on a large and high resolution image of Martian surface. Experimental results demonstrate that the proposed method can achieve less computational complexity in comparison with other crater detection methods in terms of selected features.

  5. Impact of the Radiation Boost on Outcomes After Breast-Conserving Surgery and Radiation

    International Nuclear Information System (INIS)

    Purpose: We examined the impact of radiation tumor bed boost parameters in early-stage breast cancer on local control and cosmetic outcomes. Methods and Materials: A total of 3,186 women underwent postlumpectomy whole-breast radiation with a tumor bed boost for Tis to T2 breast cancer from 1970 to 2008. Boost parameters analyzed included size, energy, dose, and technique. Endpoints were local control, cosmesis, and fibrosis. The Kaplan-Meier method was used to estimate actuarial incidence, and a Cox proportional hazard model was used to determine independent predictors of outcomes on multivariate analysis (MVA). The median follow-up was 78 months (range, 1-305 months). Results: The crude cosmetic results were excellent in 54%, good in 41%, and fair/poor in 5% of patients. The 10-year estimate of an excellent cosmesis was 66%. On MVA, independent predictors for excellent cosmesis were use of electron boost, lower electron energy, adjuvant systemic therapy, and whole-breast IMRT. Fibrosis was reported in 8.4% of patients. The actuarial incidence of fibrosis was 11% at 5 years and 17% at 10 years. On MVA, independent predictors of fibrosis were larger cup size and higher boost energy. The 10-year actuarial local failure was 6.3%. There was no significant difference in local control by boost method, cut-out size, dose, or energy. Conclusions: Likelihood of excellent cosmesis or fibrosis are associated with boost technique, electron energy, and cup size. However, because of high local control and rare incidence of fair/poor cosmesis with a boost, the anatomy of the patient and tumor cavity should ultimately determine the necessary boost parameters.

  6. RESEARCH for Face Detection on Improved Algorithm of AdaBoost

    Directory of Open Access Journals (Sweden)

    Chen Hong

    2016-01-01

    Full Text Available Face detection is basic research in computer visual field, it has important application value in the fields of cameras and surveillance and Automatic face recognition. Because traditional algorithm of AdaBoost has the problem that it needs more features and the detection speed is slow when it is used to detect face, so a improved algorithm of AdaBoost is presented. The experiment results shows that compared with traditional algorithm of AdaBoost, lower features are used in the improved algorithm and higher accuracy rate can be get and the speed of detection is improved Significantly.

  7. MedlinePlus Connect

    Science.gov (United States)

    ... IT systems, patient portals and electronic health record (EHR) systems to relevant, authoritative patient health information from ... they need it via their patient portal or EHR. How does MedlinePlus Connect work? MedlinePlus Connect responds ...

  8. A new interleaved high step-up BOOST converter%一种交错并联高升压BOOST变换器

    Institute of Scientific and Technical Information of China (English)

    汪洋; 罗全明; 支树播; 周雒维

    2013-01-01

      新能源并网发电系统中,具有高升压特性的升压变换器是不可或缺的一部分.介绍了一种交错并联BOOST变换器,具有高增益、低电压电流应力、效率高、体积小的优点.从基本BOOST变换器的开关电感三端网络出发,通过在其三条支路中串入合适极性的电压源,经过对比分析,确定了最优的高增益开关电感三端网络,最后得到一种基于拓扑组合的高增益BOOST变换器.对其工作原理和性能特点分别进行了分析,并进行了实验研究,结果表明该变换器在开关占空比D>0.5时具有如下特点:①电压增益为基本BOOST变换器的两倍;②变换器中两BOOST变换单元可实现自动均流,与传统型交错并联BOOST变换器相比,不需均流控制,控制电路简单;③有源开关的电压应力为输出电压的一半,即为基本BOOST变换器有源开关电压应力的一半.%BOOST converter is an essential part in the renewable grid-connected power system. This paper presents an interleaved boost converter with advantages of high conversion ratio, low voltage¤t stress, high efficiency and small size. Based on the three-terminal switch-inductor network of the basic BOOST converter, three high step-up three-terminal switch-inductor networks are deduced by adding a series voltage source in the three branches respectively. An optimized high step-up three-terminal switch-inductor network is determined by contrastive analysis and the high step-up BOOST converter based on topology combination is proposed. The operation principle and property of the converter are analyzed in detail and the experimental results are given. When duty ratio D>0.5, the converter has these characteristics as follows. Firstly, the voltage gain is double of the basic BOOST converter. Secondly, the two BOOST cell of the converter can realize current sharing automatically, which is unlike the interleaved BOOST converter, therefore

  9. Design and Analysis of an Improved MPPT for Photovoltaic Grid-Connected Inverter Based

    Directory of Open Access Journals (Sweden)

    Meysam Bayat

    2015-03-01

    Full Text Available One of the major drawbacks of photovoltaic (PV systems is represented by the effect of module mismatching and of partial shading of the PV field. This paper proposes a method of maximum power point tracking using Quantum behaved particle swarm optimization (QPSO for grid-connected photovoltaic systems. The system is composed of a boost converter and a Single-phase inverter connected to a utility grid. The maximum power point tracking control is based on Proposed control a switch of a boost converter. QPSO controllers provide attractive features such as fast response, good performance. The Single phase inverter uses predictive current control which provides current with sinusoidal waveform. Therefore, the system is able to deliver energy with low harmonics and high power factor. From the simulation results, the adaptive QPSO controller can deliver more power than the conventional controller.

  10. Galois connections and applications

    CERN Document Server

    Erné, M; Wismath, S

    2004-01-01

    This book presents the main ideas of General Galois Theory as a generalization of Classical Galois Theory It sketches the development of Galois connections through the last three centuries Examples of Galois connections as powerful tools in Category Theory and Universal Algebra are given Applications of Galois connections in Linguistic and Data Analysis are presented

  11. Controlled Vocabularies Boost International Participation and Normalization of Searches

    Science.gov (United States)

    Olsen, Lola M.

    2006-01-01

    The Global Change Master Directory's (GCMD) science staff set out to document Earth science data and provide a mechanism for it's discovery in fulfillment of a commitment to NASA's Earth Science progam and to the Committee on Earth Observation Satellites' (CEOS) International Directory Network (IDN.) At the time, whether to offer a controlled vocabulary search or a free-text search was resolved with a decision to support both. The feedback from the user community indicated that being asked to independently determine the appropriate 'English" words through a free-text search would be very difficult. The preference was to be 'prompted' for relevant keywords through the use of a hierarchy of well-designed science keywords. The controlled keywords serve to 'normalize' the search through knowledgeable input by metadata providers. Earth science keyword taxonomies were developed, rules for additions, deletions, and modifications were created. Secondary sets of controlled vocabularies for related descriptors such as projects, data centers, instruments, platforms, related data set link types, and locations, along with free-text searches assist users in further refining their search results. Through this robust 'search and refine' capability in the GCMD users are directed to the data and services they seek. The next step in guiding users more directly to the resources they desire is to build a 'reasoning' capability for search through the use of ontologies. Incorporating twelve sets of Earth science keyword taxonomies has boosted the GCMD S ability to help users define and more directly retrieve data of choice.

  12. Robust 3D face recognition by local shape difference boosting.

    Science.gov (United States)

    Wang, Yueming; Liu, Jianzhuang; Tang, Xiaoou

    2010-10-01

    This paper proposes a new 3D face recognition approach, Collective Shape Difference Classifier (CSDC), to meet practical application requirements, i.e., high recognition performance, high computational efficiency, and easy implementation. We first present a fast posture alignment method which is self-dependent and avoids the registration between an input face against every face in the gallery. Then, a Signed Shape Difference Map (SSDM) is computed between two aligned 3D faces as a mediate representation for the shape comparison. Based on the SSDMs, three kinds of features are used to encode both the local similarity and the change characteristics between facial shapes. The most discriminative local features are selected optimally by boosting and trained as weak classifiers for assembling three collective strong classifiers, namely, CSDCs with respect to the three kinds of features. Different schemes are designed for verification and identification to pursue high performance in both recognition and computation. The experiments, carried out on FRGC v2 with the standard protocol, yield three verification rates all better than 97.9 percent with the FAR of 0.1 percent and rank-1 recognition rates above 98 percent. Each recognition against a gallery with 1,000 faces only takes about 3.6 seconds. These experimental results demonstrate that our algorithm is not only effective but also time efficient. PMID:20724762

  13. Predictors of virologic response to ritonavir-boosted protease inhibitors.

    Science.gov (United States)

    Marcelin, Anne-Genevieve; Flandre, Philippe; Peytavin, Gilles; Calvez, Vincent

    2005-01-01

    The primary mechanism of resistance to protease inhibitors involves the stepwise accumulation of mutations that alter and block the substrate binding site of HIV protease. The large degree of cross-resistance among the different protease inhibitors is a source of considerable concern for the management of patients after treatment failure. Although the output of HIV-resistance tests has been based on therapeutically arbitrary criteria, there is now an ongoing move towards correlating test interpretation with virologic outcomes on treatment. This approach is undeniably superior, in principle, for tests intended to guide drug choices. However, the predictive accuracy of a given stratagem that links genotype or phenotype to drug response is strongly influenced by the study design, data capture and the analytical methodology used to derive it. There is no definitively superior methodology for generating a genotype-response association for use in interpreting a resistance test, and the various approaches used to date all have their strengths and weaknesses. Combining the information of therapeutic drug monitoring and resistance tests is likely to be of greatest clinical utility in antiretroviral-experienced patients harboring HIV strains with reduced susceptibility. The combination of pharmacologic and virologic parameters as a predictor of the virologic response has been merged into the parameter known as "inhibitory quotient". This article discusses the potential interest of the use of inhibitory quotients as an approach for enhancing the potency and durability of boosted protease inhibitors against protease inhibitor-resistant viruses. PMID:16425962

  14. AdaBoost-based algorithm for network intrusion detection.

    Science.gov (United States)

    Hu, Weiming; Hu, Wei; Maybank, Steve

    2008-04-01

    Network intrusion detection aims at distinguishing the attacks on the Internet from normal use of the Internet. It is an indispensable part of the information security system. Due to the variety of network behaviors and the rapid development of attack fashions, it is necessary to develop fast machine-learning-based intrusion detection algorithms with high detection rates and low false-alarm rates. In this correspondence, we propose an intrusion detection algorithm based on the AdaBoost algorithm. In the algorithm, decision stumps are used as weak classifiers. The decision rules are provided for both categorical and continuous features. By combining the weak classifiers for continuous features and the weak classifiers for categorical features into a strong classifier, the relations between these two different types of features are handled naturally, without any forced conversions between continuous and categorical features. Adaptable initial weights and a simple strategy for avoiding overfitting are adopted to improve the performance of the algorithm. Experimental results show that our algorithm has low computational complexity and error rates, as compared with algorithms of higher computational complexity, as tested on the benchmark sample data. PMID:18348941

  15. The dark matter annihilation boost from low-temperature reheating

    Science.gov (United States)

    Erickcek, Adrienne L.

    2015-11-01

    The evolution of the Universe between inflation and the onset of big bang nucleosynthesis is difficult to probe and largely unconstrained. This ignorance profoundly limits our understanding of dark matter: we cannot calculate its thermal relic abundance without knowing when the Universe became radiation dominated. Fortunately, small-scale density perturbations provide a probe of the early Universe that could break this degeneracy. If dark matter is a thermal relic, density perturbations that enter the horizon during an early matter-dominated era grow linearly with the scale factor prior to reheating. The resulting abundance of substructure boosts the annihilation rate by several orders of magnitude, which can compensate for the smaller annihilation cross sections that are required to generate the observed dark matter density in these scenarios. In particular, thermal relics with masses less than a TeV that thermally and kinetically decouple prior to reheating may already be ruled out by Fermi-LAT observations of dwarf spheroidal galaxies. Although these constraints are subject to uncertainties regarding the internal structure of the microhalos that form from the enhanced perturbations, they open up the possibility of using gamma-ray observations to learn about the reheating of the Universe.

  16. Boosting productivity: a framework for professional/amateur collaborative teamwork

    Science.gov (United States)

    Al-Shedhani, Saleh S.

    2002-11-01

    As technology advances, remote operation of telescopes has paved the way for joint observational projects between Astronomy clubs. Equipped with a small telescope, a standard CCD, and a networked computer, the observatory can be set up to carry out several photometric studies. However, most club members lack the basic training and background required for such tasks. A collaborative network between professionals and amateurs is proposed to utilize professional know-how and amateurs' readiness for continuous observations. Working as a team, various long-term observational projects can be carried out using small telescopes. Professionals can play an important role in raising the standards of astronomy clubs via specialized training programs for members on how to use the available technology to search/observe certain events (e.g. supernovae, comets, etc.). Professionals in return can accumulate a research-relevant database and can set up an early notification scheme based on comparative analyses of the recently-added images in an online archive. Here we present a framework for the above collaborative teamwork that uses web-based communication tools to establish remote/robotic operation of the telescope, and an online archive and discussion forum, to maximize the interactions between professionals and amateurs and to boost the productivity of small telescope observatories.

  17. Fault diagnosis algorithm based on switching function for boost converters

    Science.gov (United States)

    Cho, H.-K.; Kwak, S.-S.; Lee, S.-H.

    2015-07-01

    A fault diagnosis algorithm, which is necessary for constructing a reliable power conversion system, should detect fault occurrences as soon as possible to protect the entire system from fatal damages resulting from system malfunction. In this paper, a fault diagnosis algorithm is proposed to detect open- and short-circuit faults that occur in a boost converter switch. The inductor voltage is abnormally kept at a positive DC value during a short-circuit fault in the switch or at a negative DC value during an open-circuit fault condition until the inductor current becomes zero. By employing these abnormal properties during faulty conditions, the inductor voltage is compared with the switching function to detect each fault type by generating fault alarms when a fault occurs. As a result, from the fault alarm, a decision is made in response to the fault occurrence and the fault type in less than two switching time periods using the proposed algorithm constructed in analogue circuits. In addition, the proposed algorithm has good resistivity to discontinuous current-mode operation. As a result, this algorithm features the advantages of low cost and simplicity because of its simple analogue circuit configuration.

  18. Boosted Nonlinear Coherent Diffusion for Despeckling of Diagnostic Images

    Directory of Open Access Journals (Sweden)

    S.Kalaivani Narayanani

    2011-03-01

    Full Text Available Ultrasonography is a powerful technique for imaging the internal anatomy with its nature of low cost, portability, non invasive and real time imaging formation compared with other imaging modalities. Speckle noise is an inherent nature of ultrasound images, which may have negative effect on image interpretation and diagnostic tasks. It is necessary to preprocess imagery to reduce granular, texture like noise called speckle. This preprocessing is difficult when it is needed to preserve delicate image details that are buried in speckle. In this paper we present an effective approach for speckle reduction in medical diagnostic ultrasound images. This method utilizes non linear coherent diffusion model with median regularization term as boosting source for the point and linear features in image being processed. Windowed second moment tensor is used as a diffusion tensor to estimate the local coherence. Experiments have been performed on synthetic image, simulated phantom and clinical ultrasound images. The results are compared with existing state of art methods and our proposed method gives comparatively better result in term of FOM, SSIM and EPI.

  19. Negative emotion boosts quality of visual working memory representation.

    Science.gov (United States)

    Xie, Weizhen; Zhang, Weiwei

    2016-08-01

    Negative emotion impacts a variety of cognitive processes, including working memory (WM). The present study investigated whether negative emotion modulated WM capacity (quantity) or resolution (quality), 2 independent limits on WM storage. In Experiment 1, observers tried to remember several colors over 1-s delay and then recalled the color of a randomly picked memory item by clicking a best-matching color on a continuous color wheel. On each trial, before the visual WM task, 1 of 3 emotion conditions (negative, neutral, or positive) was induced by having observers to rate the valence of an International Affective Picture System image. Visual WM under negative emotion showed enhanced resolution compared with neutral and positive conditions, whereas the number of retained representations was comparable across the 3 emotion conditions. These effects were generalized to closed-contour shapes in Experiment 2. To isolate the locus of these effects, Experiment 3 adopted an iconic memory version of the color recall task by eliminating the 1-s retention interval. No significant change in the quantity or quality of iconic memory was observed, suggesting that the resolution effects in the first 2 experiments were critically dependent on the need to retain memory representations over a short period of time. Taken together, these results suggest that negative emotion selectively boosts visual WM quality, supporting the dissociable nature quantitative and qualitative aspects of visual WM representation. (PsycINFO Database Record PMID:27078744

  20. Financing maneuvers. Two opportunities to boost a hospital's working capital.

    Science.gov (United States)

    Ferconio, S; Lane, M R

    1991-10-01

    Two receivables financing approaches, factoring and asset-backed securitization, offer an initial cash flow boost and a predictable source for continual cash flow. In a typical receivables factoring program, a healthcare organization receives advance funding from its receivables and reduces collection and follow-up efforts required of its staff. In exchange, the organization: Sells receivables at a discount between 5 percent and 10 percent off face value; and Pays a factoring fee of up to 20 percent of sold receivables. In a typical asset-backed securitization: Proceeds generated from the sale of A1-rated commercial paper are used to purchase receivables from a hospital; Accounts receivable eligible for sale are advance-funded at a level between 80 and 90 percent, with the unfunded portion remaining an asset of the hospital; The hospital is responsible for collection and follow-up activities; and An asset manager maintains cash collections to retire commercial paper notes and pay administrative costs. A healthcare organization interested in receivables financing should review each option's structure and benefits to assess advance funding provided, costs, a seller's level of control, and program eligibility requirements. PMID:10145512

  1. No Money Down. Boost State Nuclear Forensics Capabilities with Less

    International Nuclear Information System (INIS)

    Any mention of boosting nuclear forensics capabilities can have governments clutching their wallets reflexively. That's because it sounds very high tech, and therefore very expensive. In a time of austerity measures, countries can find it difficult to take on additional financial responsibilities, even when those responsibilities have to do with nuclear security. But according to the IAEA's Office of Nuclear Security, becoming proficient in nuclear forensics isn't as expensive as it initially appears. Nuclear forensics is the science of uncovering the origin and history of nuclear materials, especially those found at a crime scene. ''And every country can engage in a nuclear forensics examination, using existing technical capabilities that are readily adapted as part of a nuclear security infrastructure,'' says David Smith, IAEA Nuclear Security Coordinator. ''They already have the right analytical equipment - spectrometry and inorganic chemistry equipment, for example - in universities, regulatory bodies and mining companies, just to name a few places. And they have much of the expertise - trained technicians and law enforcement officials - but are unaware that putting these things together along with workable plans and strategies - that the IAEA can provide - can create an effective means for the practice of nuclear forensics''

  2. Boosting to identify: pseudoscalar searches with di-leptonic tops

    CERN Document Server

    Goncalves, Dorival

    2016-01-01

    The quest for new heavy states is a critical component of the LHC physics program. In this letter, we study the search for pseudoscalar bosons produced in association with a $t\\bar{t}$ pair. We consider the final state $t\\bar{t} A \\to t\\bar{t} b\\bar{b}$ with di-leptonic top pair signature, and reconstruct the boosted $A \\to b\\bar{b}$ candidate with jet substructure techniques, achieving a remarkable sensitivity over a broad range of pseudoscalar masses and Yukawa couplings. We apply this strategy to a Type-I Two-Higgs-Doublet Model, demonstrating its ability to probe a realistic, UV-complete extended Higgs sector. In particular, we find that the $13~TeV$ LHC with $300~fb^{-1}$ of data can constrain the region $\\tan\\beta>1.5$ at 95$\\%$ CL for a light pseudoscalar with $m_A = 50$ GeV. Moreover, the whole mass range $20~GeV

  3. Boosting training for myoelectric pattern recognition using Mixed-LDA.

    Science.gov (United States)

    Liu, Jianwei; Sheng, Xinjun; Zhang, Dingguo; Zhu, Xiangyang

    2014-01-01

    Pattern recognition based myoelectric prostheses (MP) need a training procedure for calibrating the classifier. Due to the non-stationarity inhered in surface electromyography (sEMG) signals, the system should be retrained day by day in long-term use of MP. To boost the training procedure in later periods, we propose a method, namely Mixed-LDA, which computes the parameters of LDA through combining the model estimated on the incoming training samples of the current day with the prior models available from earlier days. An experiment ranged for 10 days on 5 subjects was carried out to simulate the long-term use of MP. Results show that the Mixed-LDA is significantly better than the baseline method (LDA) when few samples are used as training set in the new (current) day. For instance, in the task including 13 hand and wrist motions, the average classification rate of the Mixed-LDA is 88.74% when the number of training samples is 104 (LDA: 79.32%). This implies that the approach has the potential to improve the usability of MP based on pattern recognition by reducing the training time.

  4. A Boosting Multi Flyback Converter for Electric Vehicle Application

    Directory of Open Access Journals (Sweden)

    J. Sangeetha

    2015-08-01

    Full Text Available The Flyback converter belongs to the primary switched converter family, which means there is isolation between input and output. Flyback converters have low number of components compared to other Switched Mode Power Supplies (SMPSs, they also have the advantage that several isolated output voltages can be regulated by one control circuit. This study proposes an efficient and cost effective Multi Flyback topology, an isolated DC-DC converter suitable for electric vehicle applications especially driven with induction motor. The converter topology forms a power interface between the battery and the motor and also capable of boosting the voltage from low voltage battery side to high voltage DC link. A Multi Flyback Converter topology implemented by paralleling three individual flyback converters at the battery input side and DC link output side. The topology will share the current across each individual converter and the individual power will be added up at the output side. The scheme incorporates a transformer winding technique which can reduce the leakage inductance of the coupled inductor to a satisfactory limit.

  5. Ritonavir-boosted darunavir is rarely associated with nephrolithiasis compared with ritonavir-boosted atazanavir in HIV-infected patients.

    Directory of Open Access Journals (Sweden)

    Takeshi Nishijima

    Full Text Available BACKGROUND: Although ritonavir-boosted atazanavir (ATV/r is known to be associated with nephrolithiasis, little is known about the incidence of nephrolithiasis in patients treated with ritonavir-boosted Darunavir (DRV/r, the other preferred protease inhibitor. METHODS: In a single-center cohort, the incidence of nephrolithiasis was compared between HIV-infected patients who commenced DRV/r-containing antiretroviral therapy and those on ATV/r. The effects of ATV/r use over DRV/r were estimated by univariate and multivariate Cox hazards models. RESULTS: Renal stones were diagnosed in only one patient (0.86 per 1000 person-years of the DRV/r group (n=540 and 37 (20.2 per 1000 person-years of the ATV/r group (n=517. The median [interquartile (IQR] observation period in the DRV/r group was 27.1 months (IQR 18.1-38.4 months, and 40.6 months (IQR 17.5-42.7 for the ATV/r group. The total observation period was 1,163.6 person-years and 1,829.6 person-years for the DRV/r group and for the ATV/r group, respectively. In the 37 patients on ATV/r who developed nephrolithiasis, the median time from commencement of ATV/r to diagnosis was 28.1 months (IQR 18.4-42.7, whereas nephrolithiasis in the single patient of the DRV/r group occurred 11.2 month after the introduction of DRV/r. ATV/r use over DRV/r was significantly associated with nephrolithiasis by uni- and multivariate analyses (HR=26.01; 95% CI, 3.541-191.0; p=0.001 (adjusted HR=21.47; 95% CI, 2.879-160.2; p=0.003. CONCLUSION: The incidence of nephrolithiasis was substantially lower in patients on DRV/r than those on ATV/r. The results suggest that DRV/r should be selected for treatment of HIV-infected patients at risk of chronic kidney disease.

  6. Validation of the methods of cosmetic assessment after breast-conserving therapy in the EORTC 'boost versus no boost' trial

    International Nuclear Information System (INIS)

    Purpose: To evaluate both qualitative and quantitative scoring methods for the cosmetic result after breast-conserving therapy (BCT), and to compare the usefulness and reliability of these methods. Methods and Materials: In EORTC trial 22881/10882, stage I and II breast cancer patients were treated with tumorectomy and axillary dissection. A total of 5318 patients were randomized between no boost and a boost of 16 Gy following whole-breast irradiation of 50 Gy. The cosmetic result was assessed for 731 patients in two ways. A panel scored the qualitative appearance of the breast using photographs taken after surgery and 3 years later. Digitizer measurements of the displacement of the nipple were also made using these photographs in order to calculate the breast retraction assessment (BRA). The cosmetic results after 3-year follow-up were used to analyze the correlation between the panel evaluation and digitizer measurements. Results: For the panel evaluation the intraobserver agreement for the global cosmetic score as measured by the simple Kappa statistic was 0.42, considered moderate agreement. The multiple Kappa statistic for interobserver agreement for the global cosmetic score was 0.28, considered fair agreement. The specific cosmetic items scored by the panel were all significantly related to the global cosmetic score; breast size and shape influenced the global score most. For the digitizer measurements, the standard deviation from the average value of 30.0 mm was 2.3 mm (7.7%) for the intraobserver variability and 2.6 mm (8.7%) for the interobserver variability. The two methods were significantly, though moderately, correlated; some items scored by the panel were only correlated to the digitizer measurements if the tumor was not located in the inferior quadrant of the breast. Conclusions: The intra- and interobserver variability of the digitizer evaluation of cosmesis was smaller than that of the panel evaluation. However, there are some treatment sequelae

  7. Long-term outcome and toxicity of hypofractionated stereotactic body radiotherapy as a boost treatment for head and neck cancer: the importance of boost volume assessment

    Directory of Open Access Journals (Sweden)

    Lee Dong

    2012-06-01

    Full Text Available Abstract Background The aim of this study was to report the long-term clinical outcomes of patients who received stereotactic body radiotherapy (SBRT as a boost treatment for head and neck cancer. Materials and methods Between March 2004 and July 2007, 26 patients with locally advanced, medically inoperable head and neck cancer or gross residual tumors in close proximity to critical structures following head and neck surgery were treated with SBRT as a boost treatment. All patients were initially treated with standard external beam radiotherapy (EBRT. SBRT boost was prescribed to the median 80% isodose line with a median dose of 21 (range 10–25 Gy in 2–5 (median, 5 fractions. Results The median follow-up after SBRT was 56 (range 27.6 − 80.2 months. The distribution of treatment sites in 26 patients was as follows: the nasopharynx, including the base of the skull in 10 (38.5%; nasal cavity or paranasal sinus in 8 (30.8%; periorbit in 4 (15.4%; tongue in 3 (11.5%; and oropharyngeal wall in 1 (3.8%. The median EBRT dose before SBRT was 50.4 Gy (range 39.6 − 70.2. The major response rate was 100% with 21 (80.8% complete responses (CR. Severe (grade ≥ 3 late toxicities developed in 9 (34.6% patients, and SBRT boost volume was a significant parameter predicting severe late complication. Conclusions The present study demonstrates that a modern SBRT boost is a highly efficient tool for local tumor control. However, we observed a high frequency of serious late complications. More optimized dose fractionation schedule and patient selection are required to achieve excellent local control without significant late morbidities in head and neck boost treatment.

  8. Nomogram to predict ipsilateral breast relapse based on pathology review from the EORTC 22881-10882 boost versus no boost trial

    International Nuclear Information System (INIS)

    Background and purpose: The EORTC 22881-10882 trial showed that for patients treated with breast conserving therapy (BCT), a 16 Gy boost dose significantly improved local control, but increased the risk of breast fibrosis. A model to estimate the risk of ipsilateral breast relapse (IBR) already exists, but now a model has been developed which takes boost treatment into account and is based on centrally reviewed pathology. Materials and methods: A Cox model was developed based on central pathology review data and clinical data of 1603 patients from the EORTC 22881-10882 trial with a median follow-up of 11.5 years. From a predefined set of variables, predictors with a maximal effect on 10-year IBR rate >4% were retained in the model. Bootstrap re-sampling was used to assess model calibration and discrimination. The results are presented in the form of a nomogram. Results: Apart from young age and no boost, presence of DCIS adjacent to the invasive tumor was associated with increased risk of IBR (HR 1.96, p = 0.001). Patients with high grade invasive tumors were younger than patients with low/intermediate grade (p < 0.0001). The nomogram includes histologic grade, DCIS, tumor diameter, age, tamoxifen, chemotherapy, and boost with a concordance probability estimate of 0.68. Conclusions: The nomogram for predicting IBR 10 years after BCT includes seven factors, with young age, presence of DCIS and boost treatment as the most dominant factors. The nomogram estimates IBR and confirms the importance of a boost dose. Combined with a model to predict fibrosis published previously, the nomogram presented here may assist in decision making for individual patients.

  9. Hospitality industry veteran to lead workshop on boosting sales and business

    OpenAIRE

    Crumbley, Liz

    2009-01-01

    Hospitality industry expert Howard Feiertag will teach participants how to energize sales and boost business during the "Hospitality Sales" workshop, April 27 and 28 at the Hotel Roanoke and Conference Center in Roanoke, Va.

  10. An Effective Wind Energy System based on Buck-boost Controller

    Directory of Open Access Journals (Sweden)

    N. Prakash

    2013-06-01

    Full Text Available In Domestic Wind Machines, if the wind speed is low, the output voltage is not sufficient to charge the battery as it is lower than the rated charging voltage of the battery. This limits the overall efficiency of the Wind Machine to 20%. This study proposed to design and develop a Buck Boost Controller for the effective utilization of the wind machine. By implementing a controller based Buck Boost converter, the voltage produced at the lower wind speeds can also be utilized effectively by boosting it to the rated charging voltage of the battery. Also if the wind speed is high (>14 m/s, the DC output voltage will increase to more than 65 V. The converter bucks this high voltage to the nominal battery charging voltage (52 V, thereby protecting the battery from over charging voltage. Thus the effective utilization of the wind machine has been achieved by the use of the proposed Buck Boost Controller.

  11. Modeling and Simulation of Buck-Boost Converter with Voltage Feedback Control

    Directory of Open Access Journals (Sweden)

    Zhou Xuelian

    2015-01-01

    Full Text Available In order to design the control system, it is necessary to have an exact model of buck-boost converter. This paper put forward the transfer function model of buck-boost converter by the state-space average method. The open-loop transfer function model of uncompensated system is deduced according to the mathematic model of the buck-boost converter, the controller is designed according to frequency domain. The phase and magnitude margin of the open-loop system of the buck-boost converter with compensator have both been increased. After compensating, this control system has the advantages of small overshoot and short settling time. It can also improve control system’s real time property and anti-interference ability.

  12. Stable detection of expanded target by the use of boosting random ferns

    Science.gov (United States)

    Deng, Li; Wang, Chunhong; Rao, Changhui

    2012-10-01

    This paper studies the problem of keypoints recognition of extended target which lacks of texture information, and introduces an approach of stable detection of these targets called boosting random ferns (BRF). As common descriptors in this circumstance do not work as well as usual cases, matching of keypoints is hence turned into classification task so as to make use of the trainable characteristic of classifier. The kernel of BRF is consisted of random ferns as the classifier and AdaBoost (Adaptive Boosting) as the frame so that accuracy of random ferns classifier can be boosted to a relatively high level. Experiments compare BRF with widely used SURF descriptor and single random ferns classifier. The result shows that BRF obtains higher recognition rate of keypoints. Besides, for image sequence, BRF provides stronger stability than SURF in target detection, which proves the efficiency of BRF aiming to extended target which lacks of texture information.

  13. How One Clinic Got a Big Boost in HPV Vaccination Rates

    Science.gov (United States)

    ... One Clinic Got a Big Boost in HPV Vaccination Rates The cervical cancer vaccine was treated as ... the United States, lagging far behind other recommended vaccinations in this age group. But, by lumping HPV ...

  14. Asymptotically hyperbolic connections

    CERN Document Server

    Fine, Joel; Krasnov, Kirill; Scarinci, Carlos

    2015-01-01

    General Relativity in 4 dimensions can be equivalently described as a dynamical theory of SO(3)-connections rather than metrics. We introduce the notion of asymptotically hyperbolic connections, and work out an analog of the Fefferman-Graham expansion in the language of connections. As in the metric setup, one can solve the arising "evolution" equations order by order in the expansion in powers of the radial coordinate. The solution in the connection setting is arguably simpler, and very straightforward algebraic manipulations allow one to see how the obstruction appears at third order in the expansion. Another interesting feature of the connection formulation is that the "counter terms" required in the computation of the renormalised volume all combine into the Chern-Simons functional of the restriction of the connection to the boundary. As the Chern-Simons invariant is only defined modulo large gauge transformations, the requirement that the path integral over asymptotically hyperbolic connections is well-d...

  15. Design of discrete time controllers for the DC-DC boost converter

    Directory of Open Access Journals (Sweden)

    Mohammed Alkrunz

    2016-04-01

    Full Text Available In this paper, a small signal model for the boost converter is obtained. Two digital controllers using pole placement technique and Linear Quadratic Optimal Regulator (LQR methods are designed and applied to the boost converter. The compensated system’s operations and analysis are discussed and verified through MATLAB/Simulink simulation. Comparison between the two controllers related to the design methodology, implementation issues and transient measured performance is carried out.

  16. Design of discrete time controllers for the DC-DC boost converter

    OpenAIRE

    Mohammed Alkrunz; Irfan Yazıcı

    2016-01-01

    In this paper, a small signal model for the boost converter is obtained. Two digital controllers using pole placement technique and Linear Quadratic Optimal Regulator (LQR) methods are designed and applied to the boost converter. The compensated system’s operations and analysis are discussed and verified through MATLAB/Simulink simulation. Comparison between the two controllers related to the design methodology, implementation issues and transient measured performance is carried o...

  17. 8th International Workshop on Boosted Object Phenomenology, Reconstruction and Searches in HEP

    CERN Document Server

    2016-01-01

    BOOST2016 is the eighth of a series of successful joint theory/experiment workshops that bring together the world's leading experts from theory and LHC experiments to discuss the latest progress and develop new approaches on the reconstruction of and use of boosted decay topologies in order to search for new physics. This year, the workshop is jointly hosted by the University of Zurich and ETH Zurich.

  18. 7th International Workshop on Boosted Object Phenomenology, Reconstruction and Searches in HEP

    CERN Document Server

    2015-01-01

    BOOST2015 is the seventh of a series of successful joint theory/experiment workshops which bring together the world leading experts from theory and the Tevatron and LHC experiments to discuss the latest progress and develop new approaches on the reconstruction and use of boosted decay topologies as search tools for new physics. This year, the workshop is hosted by the University of Chicago.

  19. Modelado, simulación y control de un convertidor boost acoplado magnéticamente

    OpenAIRE

    Carrero Candelas, Niliana Andreina

    2014-01-01

    This thesis covered the modeling, simulation as well as the design of a control law for a coupled inductor Boost converter. In particular, from the point of view of modeling, we focused on the use of averaged modeling and linear complementarity systems (LCS), in order to obtain the dynamic of a coupled inductor Boost converter, which works in discontinuous conduction mode (DCM). The analysis of the converter was performed assuming ideal voltage-current characteristics in the switc...

  20. Comparison of three concomitant boost techniques for early-stage breast cancer

    International Nuclear Information System (INIS)

    Purpose: Whole breast radiotherapy (RT) followed by a tumor bed boost typically spans 5-6 weeks of treatment. Interest is growing in RT regimens, such as concomitant boost, that decrease overall treatment time, lessening the time/cost burden to patients and facilities. Methods and Materials: Computed tomography (CT) scans from 20 cases were selected for this retrospective, dosimetric study to compare three different techniques of concomitant boost delivery: (1) standard tangents plus an electron boost (2) intensity-modulated RT (IMRT) tangents using custom compensators plus an electron boost, and (3) IMRT tangents plus a conformal photon boost. The equivalent uniform dose model was used to compare the plans. Results: The average breast equivalent uniform dose value for the three techniques (standard, IMRT plus electrons, and IMRT plus photons) was 48.6, 47.9, and 48.3, respectively. The plans using IMRT more closely approximated the prescribed dose of 46 Gy to the whole breast. The breast volume receiving >110% of the dose was less with the IMRT tangents than with standard RT (p 0.037), but no significant difference in the maximal dose or other evaluated parameters was noted. Conclusion: Although the IMRT techniques delivered the prescribed dose with better dose uniformity, the small improvement seen did not support a goal of improved resource use

  1. Techniques of tumour bed boost irradiation in breast conserving therapy: Current evidence and suggested guidelines

    International Nuclear Information System (INIS)

    Breast conservation surgery followed by external beam radiotherapy to breast has become the standard of care in management of early carcinoma breast. A boost to the tumour bed after whole breast radiotherapy is employed in view of the pattern of tumour bed recurrences in the index quadrant and was particularly considered in patients with some adverse histopathological characteristics such as positive margins, extensive intraductal carcinoma (EIC), lymphovascular invasion (LVI), etc. There is however, now, a conclusive evidence of improvement in local control rates after a boost radiotherapy dose in patients even without such factors and for all age groups. The maximum absolute reduction of local recurrences by the addition of boost is especially seen in young premenopausal patients. At the same time, the addition of boost is associated with increased risk of worsening of cosmesis and no clear cut survival advantage. Radiological modalities such as fluoroscopy, ultrasound and CT scan have aided in accurate delineation of tumour bed with increasing efficacy. A widespread application of these techniques might ultimately translate into improved local control with minimal cosmetic deficit. The present article discusses the role of radiotherapy boost and the means to delineate and deliver the same, identify the high risk group, optimal technique and the doses and fractionations to be used. It also discusses the extent of adverse cosmetic outcome after boost delivery, means to minimise it and relevance of tumour bed in present day scenario of advanced radiotherapy delivery techniques like (IMRT)

  2. Techniques of tumour bed boost irradiation in breast conserving therapy: Current evidence and suggested guidelines

    Energy Technology Data Exchange (ETDEWEB)

    Jalali, Rakesh; Singh, Suruchi; Budrukkar, Ashwini [Tata Memorial Hospital, Mumbai (India)

    2007-10-15

    Breast conservation surgery followed by external beam radiotherapy to breast has become the standard of care in management of early carcinoma breast. A boost to the tumour bed after whole breast radiotherapy is employed in view of the pattern of tumour bed recurrences in the index quadrant and was particularly considered in patients with some adverse histopathological characteristics such as positive margins, extensive intraductal carcinoma (EIC), lymphovascular invasion (LVI), etc. There is however, now, a conclusive evidence of improvement in local control rates after a boost radiotherapy dose in patients even without such factors and for all age groups. The maximum absolute reduction of local recurrences by the addition of boost is especially seen in young premenopausal patients. At the same time, the addition of boost is associated with increased risk of worsening of cosmesis and no clear cut survival advantage. Radiological modalities such as fluoroscopy, ultrasound and CT scan have aided in accurate delineation of tumour bed with increasing efficacy. A widespread application of these techniques might ultimately translate into improved local control with minimal cosmetic deficit. The present article discusses the role of radiotherapy boost and the means to delineate and deliver the same, identify the high risk group, optimal technique and the doses and fractionations to be used. It also discusses the extent of adverse cosmetic outcome after boost delivery, means to minimise it and relevance of tumour bed in present day scenario of advanced radiotherapy delivery techniques like (IMRT)

  3. 小学语文课堂朗读教学有效性探究%On the Validity Teaching of Primary School Chinese Reading Aloud in Class

    Institute of Scientific and Technical Information of China (English)

    孙阳

    2013-01-01

    朗读是阅读学习常用方法之一,在小学语文阅读教学过程中占有举足轻重的地位。现实中,小学语文课堂中的朗读教学在重视程度、时间安排和评价考核方面均有不同程度的缺失,朗读教学并未有效发挥发展学生语言能力、阅读能力的作用。从有效教学理念入手,综合儿童心理发展在不同学段的特点和朗读教材的文本类型两个维度探讨朗读教学目标及教学注意,再次诠释有效朗读教学。教师作为教学活动的主导应当对学生抱以积极的期望,重视学生的朗读体验和领悟。教学相长,恰当的朗读教学实践和教学研究同样有助于教师专业素养的提升。%Reading teaching is the main body of primary language of teaching. In elementary student ’s learning process ,reading as an significant method of study plays an important role. However, reading teaching in emphasis, scheduling, and evaluating are different degree of loss. It did not play its role of developing student’s language ability and reading ability .This article obtains from the effective teaching, through the children’s psychological development features and reading materials type two aspects of effective reading teaching. Teachers as the leading should hold to students of the teaching activities in a positive expectation , and attache great importance to the students ’ reading experience and insights. Learning, read aloud practice and study on teaching of the moderate right also helps the professional quality of teachers improved.

  4. Supervised hashing using graph cuts and boosted decision trees.

    Science.gov (United States)

    Lin, Guosheng; Shen, Chunhua; Hengel, Anton van den

    2015-11-01

    To build large-scale query-by-example image retrieval systems, embedding image features into a binary Hamming space provides great benefits. Supervised hashing aims to map the original features to compact binary codes that are able to preserve label based similarity in the binary Hamming space. Most existing approaches apply a single form of hash function, and an optimization process which is typically deeply coupled to this specific form. This tight coupling restricts the flexibility of those methods, and can result in complex optimization problems that are difficult to solve. In this work we proffer a flexible yet simple framework that is able to accommodate different types of loss functions and hash functions. The proposed framework allows a number of existing approaches to hashing to be placed in context, and simplifies the development of new problem-specific hashing methods. Our framework decomposes the hashing learning problem into two steps: binary code (hash bit) learning and hash function learning. The first step can typically be formulated as binary quadratic problems, and the second step can be accomplished by training a standard binary classifier. For solving large-scale binary code inference, we show how it is possible to ensure that the binary quadratic problems are submodular such that efficient graph cut methods may be used. To achieve efficiency as well as efficacy on large-scale high-dimensional data, we propose to use boosted decision trees as the hash functions, which are nonlinear, highly descriptive, and are very fast to train and evaluate. Experiments demonstrate that the proposed method significantly outperforms most state-of-the-art methods, especially on high-dimensional data.

  5. Modeling laser wakefield accelerators in a Lorentz boosted frame

    Energy Technology Data Exchange (ETDEWEB)

    Vay, J.-L.; Geddes, C.G.R.; Cormier-Michel, E.; Grote, D.P.

    2010-09-15

    Modeling of laser-plasma wakefield accelerators in an optimal frame of reference [1] is shown to produce orders of magnitude speed-up of calculations from first principles. Obtaining these speedups requires mitigation of a high frequency instability that otherwise limits effectiveness in addition to solutions for handling data input and output in a relativistically boosted frame of reference. The observed high-frequency instability is mitigated using methods including an electromagnetic solver with tunable coefficients, its extension to accomodate Perfectly Matched Layers and Friedman's damping algorithms, as well as an efficient large bandwidth digital filter. It is shown that choosing theframe of the wake as the frame of reference allows for higher levels of filtering and damping than is possible in other frames for the same accuracy. Detailed testing also revealed serendipitously the existence of a singular time step at which the instability level is minimized, independently of numerical dispersion, thus indicating that the observed instability may not be due primarily to Numerical Cerenkov as has been conjectured. The techniques developed for Cerenkov mitigation prove nonetheless to be very efficient at controlling the instability. Using these techniques, agreement at the percentage level is demonstrated between simulations using different frames of reference, with speedups reaching two orders of magnitude for a 0.1 GeV class stages. The method then allows direct and efficient full-scale modeling of deeply depleted laser-plasma stages of 10 GeV-1 TeV for the first time, verifying the scaling of plasma accelerators to very high energies. Over 4, 5 and 6 orders of magnitude speedup is achieved for the modeling of 10 GeV, 100 GeV and 1 TeV class stages, respectively.

  6. Modeling laser wakefield accelerators in a Lorentz boosted frame

    Energy Technology Data Exchange (ETDEWEB)

    Vay, J.-L.; Geddes, C.G.R.; Cormier-Michel, E.; Grotec, D. P.

    2010-06-15

    Modeling of laser-plasma wakefield accelerators in an optimal frame of reference is shown to produce orders of magnitude speed-up of calculations from first principles. Obtaining these speedups requires mitigation of a high-frequency instability that otherwise limits effectiveness in addition to solutions for handling data input and output in a relativistically boosted frame of reference. The observed high-frequency instability is mitigated using methods including an electromagnetic solver with tunable coefficients, its extension to accomodate Perfectly Matched Layers and Friedman's damping algorithms, as well as an efficient large bandwidth digital filter. It is shown that choosing the frame of the wake as the frame of reference allows for higher levels of filtering and damping than is possible in other frames for the same accuracy. Detailed testing also revealed serendipitously the existence of a singular time step at which the instability level is minimized, independently of numerical dispersion, thus indicating that the observed instability may not be due primarily to Numerical Cerenkov as has been conjectured. The techniques developed for Cerenkov mitigation prove nonetheless to be very efficient at controlling the instability. Using these techniques, agreement at the percentage level is demonstrated between simulations using different frames of reference, with speedups reaching two orders of magnitude for a 0.1 GeV class stages. The method then allows direct and efficient full-scale modeling of deeply depleted laser-plasma stages of 10 GeV-1 TeV for the first time, verifying the scaling of plasma accelerators to very high energies. Over 4, 5 and 6 orders of magnitude speedup is achieved for the modeling of 10 GeV, 100 GeV and 1 TeV class stages, respectively.

  7. Effect of voltage sags on digitally controlled line connected switched-mode power supplies

    DEFF Research Database (Denmark)

    Török, Lajos; Munk-Nielsen, Stig

    2012-01-01

    Different voltage disorders like voltage fluctuations, sags, frequency variations may occur in the power supply networks due to different fault conditions. These deviations from normal operation affects in different ways the line connected devices. Standards were developed to protect and ensure...... immunity to these voltage deviations. In the following paper an analysis of different grid disturbances is presented. Some limitations and immunity requirements based on standards for devices connected to low voltage grid are described. The behavior of digitally controlled boost PFC converter in case...... of voltage sags is analyzed. Fault tolerant control algorithm was designed, implemented and is discussed. The fault conditions and their effects were investigated at different power levels....

  8. Handbook of networking & connectivity

    CERN Document Server

    McClain, Gary R

    1994-01-01

    Handbook of Networking & Connectivity focuses on connectivity standards in use, including hardware and software options. The book serves as a guide for solving specific problems that arise in designing and maintaining organizational networks.The selection first tackles open systems interconnection, guide to digital communications, and implementing TCP/IP in an SNA environment. Discussions focus on elimination of the SNA backbone, routing SNA over internets, connectionless versus connection-oriented networks, internet concepts, application program interfaces, basic principles of layering, proto

  9. Gene network-based cancer prognosis analysis with sparse boosting

    OpenAIRE

    Ma, Shuangge; Huang, Yuan; Huang, Jian; Fang, Kuangnan

    2012-01-01

    High-throughput gene profiling studies have been extensively conducted, searching for markers associated with cancer development and progression. In this study, we analyse cancer prognosis studies with right censored survival responses. With gene expression data, we adopt the weighted gene co-expression network analysis (WGCNA) to describe the interplay among genes. In network analysis, nodes represent genes. There are subsets of nodes, called modules, which are tightly connected to each othe...

  10. Asymptotically hyperbolic connections

    Science.gov (United States)

    Fine, Joel; Herfray, Yannick; Krasnov, Kirill; Scarinci, Carlos

    2016-09-01

    General relativity in four-dimensions can be equivalently described as a dynamical theory of {SO}(3)˜ {SU}(2)-connections rather than metrics. We introduce the notion of asymptotically hyperbolic connections, and work out an analogue of the Fefferman-Graham expansion in the language of connections. As in the metric setup, one can solve the arising ‘evolution’ equations order by order in the expansion in powers of the radial coordinate. The solution in the connection setting is arguably simpler, and very straightforward algebraic manipulations allow one to see how the unconstrained by Einstein equations ‘stress-energy tensor’ appears at third order in the expansion. Another interesting feature of the connection formulation is that the ‘counter terms’ required in the computation of the renormalised volume all combine into the Chern-Simons functional of the restriction of the connection to the boundary. As the Chern-Simons invariant is only defined modulo large gauge transformations, the requirement that the path integral over asymptotically hyperbolic connections is well-defined requires the cosmological constant to be quantised. Finally, in the connection setting one can deform the 4D Einstein condition in an interesting way, and we show that asymptotically hyperbolic connection expansion is universal and valid for any of the deformed theories.

  11. Inverse Degree and Connectivity

    Institute of Scientific and Technical Information of China (English)

    MA Xiao-ling; TIAN Ying-zhi

    2013-01-01

    Let G be a connected graph with vertex set V(G),order n =丨V(G)丨,minimum degree δ(G) and connectivity κ(G).The graph G is called maximally connected if κ(G) =δ(G).Define the inverse degree of G with no isolated vertices as R(G) =Σv∈V(G)1/d(v),where d(v) denotes the degree of the vertex v.We show that G is maximally connected if R(G) < 1 + 2/δ + n-2δ+1/(n-1)(n-3).

  12. An air-breathing single cell small proton exchange membrane fuel cell system with AB5-type metal hydride and an ultra-low voltage input boost converter

    Science.gov (United States)

    Akiyama, Kazuya; Matsumoto, Satoshi; Miyasaka, Akihiro; Shodai, Takahisa

    A new strategy for increasing the power density of an air-breathing small proton exchange membrane fuel cell (PEMFC) system for the main energy source of portable consumer electronics is presented. The small PEMFC system is composed of a single cell. Utilizing the output voltage of the single cell, we introduce a newly designed ultra-low voltage input boost converter. The boost converter can generate 4.1 V output from input sources with low voltage ranges, such as under 1.0 V. The cathode plate is made from a thin SUS 316L stainless steel plate and has ribs that prevent the cathode from bending. The hydrogen is supplied by a metal hydride (MH) tank cartridge. The MH tank contains highly packed AB5-type MH. The MH tank cartridge has a volume of 13.2 cm 3 and can absorb 6.7 L of hydrogen. The maximum power of the small PEMFC is 4.42 W at room temperature. Using 6.7 L of hydrogen, the small PEMFC can generate 11 Wh of electricity. The power density of the small PEMFC reaches 0.51 Wh cm -3. And the power density of the whole small PEMFC system, which contains the boost converter, a small Li-ion battery for a load absorber, and a case for the system, reaches 0.14 Wh cm -3. This value matches that of external Li-ion battery chargers for cell phones. We installed the small PEMFC system in a cell phone and confirmed the operations of calling, receiving, videophone, connecting to the Internet, and watching digital TV. And also confirmed that the small PEMFC system provides approximately 8.25 h of talk time, which is about three times as long as that for the original Li-ion battery.

  13. Li-Ion Battery Charging with a Buck-Boost Power Converter for a Solar Powered Battery Management System

    OpenAIRE

    Chien-Wei Ma; Jaw-Kuen Shiau

    2013-01-01

    This paper analyzes and simulates the Li-ion battery charging process for a solar powered battery management system. The battery is charged using a non-inverting synchronous buck-boost DC/DC power converter. The system operates in buck, buck-boost, or boost mode, according to the supply voltage conditions from the solar panels. Rapid changes in atmospheric conditions or sunlight incident angle cause supply voltage variations. This study develops an electrochemical-based equivalent circuit mod...

  14. Tokens of Connection

    Science.gov (United States)

    Crowley, Theresa

    2016-01-01

    When teachers make the effort to build a solid relationship with each student, built on trust, they often engender a life-long connection, one that's life-changing for the student. But how can teachers grow such long-lasting relationships with all students, especially disenfranchised learners and those who make it hard to connect? Crowley, a…

  15. Generalised Connections and Curvature

    OpenAIRE

    Kunzinger, Michael; Steinbauer, Roland; Vickers, James A.

    2004-01-01

    The concept of generalised (in the sense of Colombeau) connection on a principal fibre bundle is introduced. This definition is then used to extend results concerning the geometry of principal fibre bundles to those that only have a generalised connection. Some applications to singular solutions of Yang-Mills theory are given.

  16. Generalized connectivity of graphs

    CERN Document Server

    Li, Xueliang

    2016-01-01

    Noteworthy results, proof techniques, open problems and conjectures in generalized (edge-) connectivity are discussed in this book. Both theoretical and practical analyses for generalized (edge-) connectivity of graphs are provided. Topics covered in this book include: generalized (edge-) connectivity of graph classes, algorithms, computational complexity, sharp bounds, Nordhaus-Gaddum-type results, maximum generalized local connectivity, extremal problems, random graphs, multigraphs, relations with the Steiner tree packing problem and generalizations of connectivity. This book enables graduate students to understand and master a segment of graph theory and combinatorial optimization. Researchers in graph theory, combinatorics, combinatorial optimization, probability, computer science, discrete algorithms, complexity analysis, network design, and the information transferring models will find this book useful in their studies.

  17. Handbook of Brain Connectivity

    CERN Document Server

    Jirsa, Viktor K

    2007-01-01

    Our contemporary understanding of brain function is deeply rooted in the ideas of the nonlinear dynamics of distributed networks. Cognition and motor coordination seem to arise from the interactions of local neuronal networks, which themselves are connected in large scales across the entire brain. The spatial architectures between various scales inevitably influence the dynamics of the brain and thereby its function. But how can we integrate brain connectivity amongst these structural and functional domains? Our Handbook provides an account of the current knowledge on the measurement, analysis and theory of the anatomical and functional connectivity of the brain. All contributors are leading experts in various fields concerning structural and functional brain connectivity. In the first part of the Handbook, the chapters focus on an introduction and discussion of the principles underlying connected neural systems. The second part introduces the currently available non-invasive technologies for measuring struct...

  18. Application of Boosting Regression Trees to Preliminary Cost Estimation in Building Construction Projects

    Directory of Open Access Journals (Sweden)

    Yoonseok Shin

    2015-01-01

    Full Text Available Among the recent data mining techniques available, the boosting approach has attracted a great deal of attention because of its effective learning algorithm and strong boundaries in terms of its generalization performance. However, the boosting approach has yet to be used in regression problems within the construction domain, including cost estimations, but has been actively utilized in other domains. Therefore, a boosting regression tree (BRT is applied to cost estimations at the early stage of a construction project to examine the applicability of the boosting approach to a regression problem within the construction domain. To evaluate the performance of the BRT model, its performance was compared with that of a neural network (NN model, which has been proven to have a high performance in cost estimation domains. The BRT model has shown results similar to those of NN model using 234 actual cost datasets of a building construction project. In addition, the BRT model can provide additional information such as the importance plot and structure model, which can support estimators in comprehending the decision making process. Consequently, the boosting approach has potential applicability in preliminary cost estimations in a building construction project.

  19. Comprehensive review of high power factor ac-dc boost converters for PFC applications

    Science.gov (United States)

    De Castro Pereira, Dênis; Da Silva, Márcio Renato; Mateus Silva, Elder; Lessa Tofoli, Fernando

    2015-08-01

    High power factor rectifiers have been consolidated as an effective solution to improve power quality indices in terms of input power factor correction, reduction in the total harmonic distortion of the input current and also regulated dc voltages. Within this context, this subject has motivated the introduction of numerous converter topologies based on classic dc-dc structures associated with novel control techniques, thus leading to the manufacturing of dedicated integrated circuits that allow high input power factor by adding a front-end stage to switch-mode converters. In particular, boost converters in continuous current mode (CCM) are widely employed since they allow obtaining minimised electromagnetic interference levels. This work is concerned with a literature review involving relevant ac-dc single-phase boost-based topologies with high input power factor. The evolution of aspects regarding the conventional boost converter is shown in terms of improved characteristics inherent to other ac-dc boost converters. Additionally, the work intends to be a fast and concise reference to single-phase ac-dc boost converters operating in CCM for engineers, researchers and experts in the field of power electronics by properly analysing and comparing the aforementioned rectifiers.

  20. FULL ELECTROMAGNETIC FEL SIMULATION VIA THE LORENTZ-BOOSTED FRAME TRANSFORMATION

    Energy Technology Data Exchange (ETDEWEB)

    Fawley, William; Vay, Jean-Luc

    2010-08-16

    Numerical electromagnetic simulation of some systems containing charged particles with highly relativistic directed motion can by speeded up by orders of magnitude by choice of the proper Lorentz-boosted frame. A particularly good application for calculation in a boosted frame isthat of short wavelength free-electron lasers (FELs) where a high energy electron beam with small fractional energy spread interacts with a static magnetic undulator. In the optimal boost frame (i.e., the ponderomotive rest frame), the red-shifted FEL radiation and blue-shifted undulator field have identical wavelengths and the number of required longitudinal grid cells and time-steps for fully electromagnetic simulation (relative to the laboratory frame) decrease by factors of gamma^2 each. In theory, boosted frame EM codes permit direct study of FEL problems for which the eikonal approximation for propagation of the radiation field and wiggler-period-averaging for the particle-field interaction may be suspect. We have adapted the WARP code to apply this method to several electromagnetic FEL problems including spontaneous emission, strong exponential gain in a seeded, single pass amplifier configuration, and emission from e-beams in undulators with multiple harmonic components. WARP has a standard relativistic macroparticle mover and a fully 3-D electromagnetic field solver. We discuss our boosted frame results and compare with those obtained using the ?standard? eikonal FEL simulation approach.

  1. Heterologous Prime-Boost HIV-1 Vaccination Regimens in Pre-Clinical and Clinical Trials

    Directory of Open Access Journals (Sweden)

    Julia L. Hurwitz

    2010-02-01

    Full Text Available Currently, there are more than 30 million people infected with HIV-1 and thousands more are infected each day. Vaccination is the single most effective mechanism for prevention of viral disease, and after more than 25 years of research, one vaccine has shown somewhat encouraging results in an advanced clinical efficacy trial. A modified intent-to-treat analysis of trial results showed that infection was approximately 30% lower in the vaccine group compared to the placebo group. The vaccine was administered using a heterologous prime-boost regimen in which both target antigens and delivery vehicles were changed during the course of inoculations. Here we examine the complexity of heterologous prime-boost immunizations. We show that the use of different delivery vehicles in prime and boost inoculations can help to avert the inhibitory effects caused by vector-specific immune responses. We also show that the introduction of new antigens into boost inoculations can be advantageous, demonstrating that the effect of ‘original antigenic sin’ is not absolute. Pre-clinical and clinical studies are reviewed, including our own work with a three-vector vaccination regimen using recombinant DNA, virus (Sendai virus or vaccinia virus and protein. Promising preliminary results suggest that the heterologous prime-boost strategy may possibly provide a foundation for the future prevention of HIV-1 infections in humans.

  2. A New Method for Start-up of Isolated Boost Converters Using Magnetic- and Winding-Integration

    DEFF Research Database (Denmark)

    Lindberg-Poulsen, Kristian; Ouyang, Ziwei; Sen, Gökhan;

    2012-01-01

    . The traditional added flyback winding coupled to the boost inductor is thus eliminated from the circuit, bringing substantial cost savings, increased efficiency and simplified design. Each subinterval of the converter operation is described through electrical and magnetic circuit diagrams, and the concept...... is extended to other isolated boost family topologies. The principle of operation is demonstrated with a 800W isolated boost prototype, and a 1600W primary parallel series secondary isolated boost converter. Efficiency measurements of both prototypes are presented, including measurements during both start...

  3. An evaluation of college and low-income youth writing together: self-discovery and cultural connection.

    Science.gov (United States)

    Chandler, Genevieve E

    2002-01-01

    Although the health and healing effects of writing have been documented in the literature, most of the studies have focused primarily on individuals writing alone. This formative evaluation is a component of an intervention reported elsewhere. The evaluation describes the experience of low-income youth and college students (n = 7) writing in a group during a 10-week workshop. The results revealed the development of protective processes of self-esteem, self-efficacy, coping strategies, social support, and cultural connections. In the weekly 2-hr writing sessions, using the Amherst Writers and Artists method, participants were encouraged to write their stories in their own voices in response to prompts, followed by reading aloud and positive feedback. At the end of the 10 weeks participants were interviewed about their experience within the group and outside the group. Analysis of interviews revealed two themes that emerged from the experience of writing together: connection to self through feelings, reflection, and behaviors; and connection to others through learning and empathy. The results suggest that writing in a group using a specific approach facilitated emotional catharsis, increased self knowledge, coping strategies, and understanding and appreciating of others.

  4. Boosted Object Tagging with Variable-$R$ Jets in the ATLAS Detector

    CERN Document Server

    The ATLAS collaboration

    2016-01-01

    A comprehensive study of the performance of variable-$R$ jets in the reconstruction of highly energetic (boosted) top quarks, Higgs bosons and $W$ bosons is presented. The effective size of a variable-$R$ jet depends on its transverse momentum, making these jets ideally suited for boosted decay topologies as the separation between the decay products of a heavy particle decreases with its transverse momentum. The performance of ungroomed and trimmed variable-$R$ jets is studied and compared to that of trimmed anti-$k_t$ $R=1.0$ jets in events simulated with Monte Carlo generators using the full ATLAS detector simulation. Significant performance improvements are found with variable-$R$ jets for a number of discriminating variables used in boosted object taggers, in particular the jet mass and the first $k_t$ splitting scale.

  5. Pulse width modulated buck-boost five-level current source inverters

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Gao, F.; Loh, P.C.;

    2008-01-01

    This paper presents new five-level current source inverters (CSIs) with voltage/current buck-boost capability. Being different from the existing multilevel CSI, the proposed CSIs were first designed to regulate the flowing path of dc input current by controlling two additional active switches......, resulting in the natural balance of input current. For maintaining the normalized volt-sec average unchanged, the alternative phase opposition disposition (APOD) modulation scheme with typical gating signal mapping technique from voltage source inverter (VSI) to CSI can be assumed to control the five-level...... buck-boost CSIs. Next by observing the hidden current charging path during inductive charging interval under APOD modulation, it is noted that the buck-boost five-level CSI can then be further modified with lesser active component without degrading output performance. To verify the theoretical findings...

  6. Immune boosting explains regime-shifts in prevaccine-era pertussis dynamics.

    Directory of Open Access Journals (Sweden)

    Jennie S Lavine

    Full Text Available Understanding the biological mechanisms underlying episodic outbreaks of infectious diseases is one of mathematical epidemiology's major goals. Historic records are an invaluable source of information in this enterprise. Pertussis (whooping cough is a re-emerging infection whose intermittent bouts of large multiannual epidemics interspersed between periods of smaller-amplitude cycles remain an enigma. It has been suggested that recent increases in pertussis incidence and shifts in the age-distribution of cases may be due to diminished natural immune boosting. Here we show that a model that incorporates this mechanism can account for a unique set of pre-vaccine-era data from Copenhagen. Under this model, immune boosting induces transient bursts of large amplitude outbreaks. In the face of mass vaccination, the boosting model predicts larger and more frequent outbreaks than do models with permanent or passively-waning immunity. Our results emphasize the importance of understanding the mechanisms responsible for maintaining immune memory for pertussis epidemiology.

  7. GI boosting: Direct measurement of intrinsic alignments in cosmic shear data

    CERN Document Server

    Joachimi, B

    2010-01-01

    Intrinsic alignments constitute the major astrophysical systematic for cosmological weak lensing surveys. We present a purely geometrical method with which one can study gravitational shear-intrinsic ellipticity correlations directly in weak lensing data. Linear combinations of second-order cosmic shear measures are constructed such that the intrinsic alignment signal is boosted while suppressing the contribution by gravitational lensing. We then assess the performance of a specific parametrisation of the weights entering these linear combinations for three representative survey models. Moreover a relation between this boosting technique and the intrinsic alignment removal via nulling is derived. For future all-sky weak lensing surveys with photometric redshift information the boosting technique yields statistical errors on model parameters of intrinsic alignments whose order of magnitude is compatible with current constraints determined from indirect measurements. Parameter biases due to a residual cosmic sh...

  8. Non-Inverting Buck-Boost Converter for Fuel Cell Applications

    DEFF Research Database (Denmark)

    Schaltz, Erik; Rasmussen, Peter Omand; Khaligh, Alireza

    2008-01-01

    Fuel cell DC/DC converters often have to be able to both step-up and step-down the input voltage, and provide a high efficiency in the whole range of output power. Conventional negative output buck-boost and non-inverting buck-boost converters provide both step-up and step-down characteristics....... In this paper the non-inverting buck-boost with either diodes or synchronous rectifiers is investigated for fuel cell applications. Most of previous research does not consider  the parasitic in the evaluation of the converters. In this study, detailed analytical expressions of the efficiencies for the system...... composed of fuel cell system and interfacing converter, considering the parasitics, are presented. It is concluded that the implementation with synchronous rectifiers provides the highest efficiency in the whole range of the fuel cell power, and its efficiency characteristic is more suitable for fuel cell...

  9. Fission dynamics within time-dependent Hartree-Fock: boost-induced fission

    CERN Document Server

    Goddard, P M; Rios, A

    2015-01-01

    Background: Nuclear fission is a complex large-amplitude collective decay mode in heavy nuclei. Microscopic density functional studies of fission have previously concentrated on adiabatic approaches based on constrained static calculations ignoring dynamical excitations of the fissioning nucleus, and the daughter products. Purpose: To explore the ability of dynamic mean-field methods to describe induced fission processes, using quadrupole boosts in the nuclide $^{240}$Pu as an example. Methods: Quadrupole constrained Hartree-Fock calculations are used to create a potential energy surface. An isomeric state and a state beyond the second barrier peak are excited by means of instantaneous as well as temporally extended gauge boosts with quadrupole shapes. The subsequent deexcitation is studied in a time-dependent Hartree-Fock simulation, with emphasis on fissioned final states. The corresponding fission fragment mass numbers are studied. Results: In general, the energy deposited by the quadrupole boost is quickl...

  10. Introducing state-trajectory control for the synchronous interleaved boost converter

    DEFF Research Database (Denmark)

    Peña-Alzola, Rafael; Ksiazek, Peter; Ordonez, Martin;

    2015-01-01

    Synchronous interleaved boost converters (SIBCs) result in lower ripple currents and bidirectional power flow. The boost topology has a non-minimum phase characteristic, producing instability problems when a large bandwidth is required. Linear controllers inherently limit the boost controller...... bandwidth, resulting in a slow response. In this paper, state-trajectory control of the SIBC based on boundary control is proposed to provide an outstanding dynamic response during start-up and sudden load changes, close to the physical limit of the system. The proposed controller and derivation provides...... a rigorous framework that deals with four switching states, and three state equations, resulting in a simple control law with very fast dynamic response. The normalized trajectories for the SIBC are determined in the geometric domain along with the control law. The exact trajectories are used for fast...

  11. In vivo quantitative evaluation of vascular parameters for angiogenesis based on sparse principal component analysis and aggregated boosted trees

    Science.gov (United States)

    Zhao, Fengjun; Liu, Junting; Qu, Xiaochao; Xu, Xianhui; Chen, Xueli; Yang, Xiang; Cao, Feng; Liang, Jimin; Tian, Jie

    2014-12-01

    To solve the multicollinearity issue and unequal contribution of vascular parameters for the quantification of angiogenesis, we developed a quantification evaluation method of vascular parameters for angiogenesis based on in vivo micro-CT imaging of hindlimb ischemic model mice. Taking vascular volume as the ground truth parameter, nine vascular parameters were first assembled into sparse principal components (PCs) to reduce the multicolinearity issue. Aggregated boosted trees (ABTs) were then employed to analyze the importance of vascular parameters for the quantification of angiogenesis via the loadings of sparse PCs. The results demonstrated that vascular volume was mainly characterized by vascular area, vascular junction, connectivity density, segment number and vascular length, which indicated they were the key vascular parameters for the quantification of angiogenesis. The proposed quantitative evaluation method was compared with both the ABTs directly using the nine vascular parameters and Pearson correlation, which were consistent. In contrast to the ABTs directly using the vascular parameters, the proposed method can select all the key vascular parameters simultaneously, because all the key vascular parameters were assembled into the sparse PCs with the highest relative importance.

  12. Application of a DC–DC boost converter with maximum power point tracking for low power thermoelectric generators

    International Nuclear Information System (INIS)

    Highlights: • Charges with direct and MPPT conditions have been compared. • Perturb and observation method has been practically tested on a new TEG. • Matched load condition has been experimentally investigated. • To increase the efficiency of a TEG, the charge with MPPT should be used. • The charge with MPPT provides twice-fold increase in efficiency. - Abstract: Thermoelectric generators (TEGs) directly generate electrical power from the geothermal/waste heat as well as contribute to efficient usage of the energy. TEGs cannot be operated at full capacity without additional electronic equipments, since the internal resistances of TEGs are not equal to the device resistances connected across TEGs. For this reason, in this paper, the application of a DC–DC boost converter with maximum power point tracking (MPPT) based on microcontroller embedded in perturb and observe (P&O) algorithm has been proposed to obtain maximum power from a newly designed portable TEG (pTEG) in a real TEG system. The matched condition load for the pTEG has been experimentally investigated. Firstly, the pTEG has been directly charged to the battery pack, secondly it has been charged through the improved convertor with MPPT. In the first one, the pTEG operated with less efficiency than half of its full capacity, whereas, in the second, the pTEG operated efficiency near its full capacity

  13. Boosted Tidal Disruption by Massive Black Hole Binaries During Galaxy Mergers - In The View of N-Body Simulation

    CERN Document Server

    Li, Shuo; Berczik, Peter; Spurzem, Rainer

    2015-01-01

    Supermassive black hole binaries (SMBHBs) are productions of the hierarchical galaxy formation model. There are many close connections between central SMBH and its host galaxy because the former plays very important roles on the formation and evolution of a galaxy. For this reason, the evolution of SMBHBs in merging galaxies is an essential problem. Since there are many discussions about SMBHB evolution in gas rich environment, we focus on the quiescent galaxy, using tidal disruption as a diagnostic tool. Our study is based on a series of numerical large particle number direct N-body simulations for dry major mergers. According to the simulation results, the evolution can be divided into three phases. In phase I, the tidal disruption rate for two well separated SMBHs in merging system has similar level to single SMBH in isolate galaxy. After two SMBHs getting close enough to form a bound binary in phase II, the disruption rate can be enhanced for ~ 2 order of magnitudes within a short time. This "boosted" dis...

  14. Covariant Magnetic Connection Hypersurfaces

    CERN Document Server

    Pegoraro, F

    2016-01-01

    In the single fluid, nonrelativistic, ideal-Magnetohydrodynamic (MHD) plasma description magnetic field lines play a fundamental role by defining dynamically preserved "magnetic connections" between plasma elements. Here we show how the concept of magnetic connection needs to be generalized in the case of a relativistic MHD description where we require covariance under arbitrary Lorentz transformations. This is performed by defining 2-D {\\it magnetic connection hypersurfaces} in the 4-D Minkowski space. This generalization accounts for the loss of simultaneity between spatially separated events in different frames and is expected to provide a powerful insight into the 4-D geometry of electromagnetic fields when ${\\bf E} \\cdot {\\bf B} = 0$.

  15. Covariant magnetic connection hypersurfaces

    Science.gov (United States)

    Pegoraro, F.

    2016-04-01

    > In the single fluid, non-relativistic, ideal magnetohydrodynamic (MHD) plasma description, magnetic field lines play a fundamental role by defining dynamically preserved `magnetic connections' between plasma elements. Here we show how the concept of magnetic connection needs to be generalized in the case of a relativistic MHD description where we require covariance under arbitrary Lorentz transformations. This is performed by defining 2-D magnetic connection hypersurfaces in the 4-D Minkowski space. This generalization accounts for the loss of simultaneity between spatially separated events in different frames and is expected to provide a powerful insight into the 4-D geometry of electromagnetic fields when .

  16. Long-Term Results of Targeted Intraoperative Radiotherapy (Targit) Boost During Breast-Conserving Surgery

    International Nuclear Information System (INIS)

    Purpose: We have previously shown that delivering targeted radiotherapy to the tumour bed intraoperatively is feasible and desirable. In this study, we report on the feasibility, safety, and long-term efficacy of TARGeted Intraoperative radioTherapy (Targit), using the Intrabeam system. Methods and Materials: A total of 300 cancers in 299 unselected patients underwent breast-conserving surgery and Targit as a boost to the tumor bed. After lumpectomy, a single dose of 20 Gy was delivered intraoperatively. Postoperative external beam whole-breast radiotherapy excluded the usual boost. We also performed a novel individualized case control (ICC) analysis that computed the expected recurrences for the cohort by estimating the risk of recurrence for each patient using their characteristics and follow-up period. Results: The treatment was well tolerated. The median follow up was 60.5 months (range, 10–122 months). Eight patients have had ipsilateral recurrence: 5-year Kaplan Meier estimate for ipsilateral recurrence is 1.73% (SE 0.77), which compares well with that seen in the boosted patients in the European Organization for Research and Treatment of Cancer study (4.3%) and the UK STAndardisation of breast RadioTherapy study (2.8%). In a novel ICC analysis of 242 of the patients, we estimated that there should be 11.4 recurrences; in this group, only 6 recurrences were observed. Conclusions: Lumpectomy and Targit boost combined with external beam radiotherapy results in a low local recurrence rate in a standard risk patient population. Accurate localization and the immediacy of the treatment that has a favorable effect on tumour microenvironment may contribute to this effect. These long-term data establish the long-term safety and efficacy of the Targit technique and generate the hypothesis that Targit boost might be superior to an external beam boost in its efficacy and justifies a randomized trial.

  17. Fission dynamics within time-dependent Hartree-Fock. II. Boost-induced fission

    Science.gov (United States)

    Goddard, Philip; Stevenson, Paul; Rios, Arnau

    2016-01-01

    Background: Nuclear fission is a complex large-amplitude collective decay mode in heavy nuclei. Microscopic density functional studies of fission have previously concentrated on adiabatic approaches based on constrained static calculations ignoring dynamical excitations of the fissioning nucleus and the daughter products. Purpose: We explore the ability of dynamic mean-field methods to describe induced fission processes, using quadrupole boosts in the nuclide 240Pu as an example. Methods: Following upon the work presented in Goddard et al. [Phys. Rev. C 92, 054610 (2015)], 10.1103/PhysRevC.92.054610, quadrupole-constrained Hartree-Fock calculations are used to create a potential energy surface. An isomeric state and a state beyond the second barrier peak are excited by means of instantaneous as well as temporally extended gauge boosts with quadrupole shapes. The subsequent deexcitation is studied in a time-dependent Hartree-Fock simulation, with emphasis on fissioned final states. The corresponding fission fragment mass numbers are studied. Results: In general, the energy deposited by the quadrupole boost is quickly absorbed by the nucleus. In instantaneous boosts, this leads to fast shape rearrangements and violent dynamics that can ultimately lead to fission. This is a qualitatively different process than the deformation-induced fission. Boosts induced within a finite time window excite the system in a relatively gentler way and do induce fission but with a smaller energy deposition. Conclusions: The fission products obtained using boost-induced fission in time-dependent Hartree-Fock are more asymmetric than the fragments obtained in deformation-induced fission or the corresponding adiabatic approaches.

  18. Which patients don't need a tumor-bed boost after whole-breast radiotherapy?

    International Nuclear Information System (INIS)

    Background: Retrospective dose-response data suggest that a boost of about 15 Gy to the tumor bed following whole-breast radiotherapy reduces the risk of local recurrence (IBTR) by as much as 2-fold. Even if this benefit is confirmed by prospective trials, boost irradiation may not be considered cost-effective in patients having an IBTR risk of less than 1% per annum. Methods: Published prospective trials of invasive breast cancers (National Surgical Adjuvant Breast and Bowel Project; Stockholm Adjuvant Tamoxifen Trial) in which patients received 50 Gy whole-breast irradiation, without a boost, were analyzed to identify subgroups with IBTR risk less than 1% per year. All studies were based on lumpectomy (rather than segmental or quadrant excision) and eligibility required the absence of cancer cells at the margins. It was assumed that clinical and pathological factors, other than those defining trial eligibility, were of negligible importance regarding IBTR risk, with the exception of young age. Results: All patients not receiving adjuvant systemic therapy, including tumors<1 cm, have IBTR risk justifying boost irradiation. Of patients receiving systemic therapy, only patients with node-negative, estrogen receptor-positive tumors have low IBTR risk (3% at 10 years), provided that tamoxifen is administered. Of patients receiving only adjuvant chemotherapy, low IBTR risk seems to be associated with administration concomitantly with radiotherapy. IBTR risk in patients receiving chemotherapy sequentially with respect to radiotherapy probably is high enough to justify a boost. A boost is probably indicated in all patients younger than 40 years, regardless of other factors. (orig.)

  19. Dosimetric evaluation of simultaneous integrated boost during stereotactic body radiation therapy for pancreatic cancer

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Wensha, E-mail: wensha.yang@cshs.org [Department of Radiation Oncology, Cedars Sinai Medical Center, Los Angeles, CA (United States); Reznik, Robert; Fraass, Benedick A. [Department of Radiation Oncology, Cedars Sinai Medical Center, Los Angeles, CA (United States); Nissen, Nicholas [Department of Surgery, Cedars Sinai Medical Center, Los Angeles, CA (United States); Hendifar, Andrew [Department of Gastrointestinal Oncology, Cedars Sinai Medical Center, Los Angeles, CA (United States); Wachsman, Ashley [Department of Cross-Sectional Imaging Interventional Oncology, Cedars Sinai Medical Center, Los Angeles, CA (United States); Sandler, Howard; Tuli, Richard [Department of Radiation Oncology, Cedars Sinai Medical Center, Los Angeles, CA (United States)

    2015-04-01

    Stereotactic body radiation therapy (SBRT) provides a promising way to treat locally advanced pancreatic cancer and borderline resectable pancreatic cancer. A simultaneous integrated boost (SIB) to the region of vessel abutment or encasement during SBRT has the potential to downstage otherwise likely positive surgical margins. Despite the potential benefit of using SIB-SBRT, the ability to boost is limited by the local geometry of the organs at risk (OARs), such as stomach, duodenum, and bowel (SDB), relative to tumor. In this study, we have retrospectively replanned 20 patients with 25 Gy prescribed to the planning target volume (PTV) and 33~80 Gy to the boost target volume (BTV) using an SIB technique for all patients. The number of plans and patients able to satisfy a set of clinically established constraints is analyzed. The ability to boost vessels (within the gross target volume [GTV]) is shown to correlate with the overlap volume (OLV), defined to be the overlap between the GTV + a 1(OLV1)- or 2(OLV2)-cm margin with the union of SDB. Integral dose, boost dose contrast (BDC), biologically effective BDC, tumor control probability for BTV, and normal tissue complication probabilities are used to analyze the dosimetric results. More than 65% of the cases can deliver a boost to 40 Gy while satisfying all OAR constraints. An OLV2 of 100 cm{sup 3} is identified as the cutoff volume: for cases with OLV2 larger than 100 cm{sup 3}, it is very unlikely the case could achieve 25 Gy to the PTV while successfully meeting all the OAR constraints.

  20. Role of the primary motor cortex in the early boost in performance following mental imagery training.

    Directory of Open Access Journals (Sweden)

    Ursula Debarnot

    Full Text Available Recently, it has been suggested that the primary motor cortex (M1 plays a critical role in implementing the fast and transient post-training phase of motor skill consolidation, known to yield an early boost in performance. Whether a comparable early boost in performance occurs following motor imagery (MIM training is still unknown. To address this issue, two groups of subjects learned a finger tapping sequence either by MIM or physical practice (PP. In both groups, performance increased significantly in the post-training phase when compared with the pre-training phase and further increased after a 30 min resting period, indicating that both MIM and PP trainings were equally efficient and induced an early boost in motor performance. This conclusion was corroborated by the results of an additional control group. In a second experiment, we then investigated the causal role of M1 in implementing the early boost process resulting from MIM training. To do so, we inhibited M1 by applying a continuous theta-burst stimulation (cTBS in healthy volunteers just after they learnt, by MIM, the same finger-tapping task as in Experiment #1. As a control, cTBS was applied over the vertex of subjects who underwent the same experiment. We found that cTBS applied over M1 selectively abolished the early boost process subsequent to MIM training. Altogether, the present study provides evidence that MIM practice induces an early boost in performance and demonstrates that M1 is causally involved in this process. These findings further divulge some degree of behavioral and neuronal similitude between MIM and PP.

  1. A Zero Input Current Ripple ZVS/ZCS Boost Converter with Boundary-Mode Control

    OpenAIRE

    Ching-Ming Lai; Ming-Ji Yang; Shih-Kun Liang

    2014-01-01

    In this paper, in order to achieve zero ripple conditions, the use of a ripple mirror (RM) circuit for the boost converter is proposed. The operation modes are studied and steady-state analyses performed to show the merits of the proposed converter. It is found that the proposed RM circuit technique can provide much better flexibility than the two-phase interleaved boost converter for locating the zero ripple operating point in the design stage. In addition, the choice of using a boundary-mod...

  2. A new DC/AC boost transformerless converter in application of photovoltaic power generation

    DEFF Research Database (Denmark)

    Wei, Mo; Loh, Poh Chiang; Blaabjerg, Frede

    2011-01-01

    This paper presents a new DC/AC boost transformerless converter in the applications of photovoltaic (PV) power generation. A new circuit topology of single phase full bridge power inverter with additional DC/DC boost stage is proposed. The proposed topology overcomes two commonly existing......, and then converts the DC into AC to supply the load. A special modulation technique is proposed to eliminate the leakage current which is commonly presents in PV transformerless power generation, helps to increase the system efficiency and output performance....

  3. Modeling and Analysis of Transformerless High Gain Buck-boost DC-DC Converters

    Directory of Open Access Journals (Sweden)

    Vu Tran

    2014-12-01

    Full Text Available This paper proposes a transfomerless switched capacitor buck boost converter model, which provides higher voltage gain and higher efficiency when compared to the conventional buck boost converter. The averaged model based on state-space description is analyzed in the paper. The simulation results are presented to confirm the capability of the converter to generate high voltage ratios. The comparison between the proposed model and the traditional model is also provided to reveal the improvement. The proposed converter is suitable for for a wide application which requires high step-up DC-DC converters such as DC micro-grids and solar electrical energy.

  4. Development of TMS320F2810 DSP Based Bidirectional buck-boost Chopper

    OpenAIRE

    Mr. K.S. Chakradhar*1,; M.Ayesha siddiqa2; T.Vandhana3

    2014-01-01

    A DC - DC converter is an electronic circuit which converts a source of direct current (DC) from one voltage level to another. It is a class of power converter. One common application of DC - DC converters is DC motor control. The Buck - Boost Chopper is a type of DC - DC converter. They are static devices which are used to obtain variable DC voltage from the source of constant DC voltage. Besides the saving in power, Buck-Boost choppers offer greater efficiency, faster respon...

  5. Analysis of high voltage step-up nonisolated DC-DC boost converters

    Science.gov (United States)

    Alisson Alencar Freitas, Antônio; Lessa Tofoli, Fernando; Junior, Edilson Mineiro Sá; Daher, Sergio; Antunes, Fernando Luiz Marcelo

    2016-05-01

    A high voltage step-up nonisolated DC-DC converter based on coupled inductors suitable to photovoltaic (PV) systems applications is proposed in this paper. Considering that numerous approaches exist to extend the voltage conversion ratio of DC-DC converters that do not use transformers, a detailed comparison is also presented among the proposed converter and other popular topologies such as the conventional boost converter and the quadratic boost converter. The qualitative analysis of the coupled-inductor-based topology is developed so that a design procedure can be obtained, from which an experimental prototype is implemented to validate the theoretical assumptions.

  6. Differential Mode EMI Filter Design for Isolated DC-DC Boost Converter

    DEFF Research Database (Denmark)

    Makda, Ishtiyaq Ahmed; Nymand, Morten

    2014-01-01

    A Differential Mode EMI filter for a low input voltage high-current isolated dc-dc boost converter is designed and presented in this paper. The primary side Differential Mode noise voltage is low due to the high transformer turn ratio, however, the input current is very high and since the EMI limit...... is identified first. The DM noise model is then established and based on the harmonic analysis of the noise source voltage waveform, the complete Differential Mode EMI filter, including the filter resonance damping branch, is designed for a 3kW isolated dc-dc boost converter. The noise model and its theoretical...

  7. Boosted and Linked Mixtures of HMMs for Brain-Machine Interfaces

    Science.gov (United States)

    Darmanjian, Shalom; Principe, Jose C.

    2008-12-01

    We propose two algorithms that decompose the joint likelihood of observing multidimensional neural input data into marginal likelihoods. The first algorithm, boosted mixtures of hidden Markov chains (BMs-HMM), applies techniques from boosting to create implicit hierarchic dependencies between these marginal subspaces. The second algorithm, linked mixtures of hidden Markov chains (LMs-HMM), uses a graphical modeling framework to explicitly create the hierarchic dependencies between these marginal subspaces. Our results show that these algorithms are very simple to train and computationally efficient, while also reducing the input dimensionality for brain-machine interfaces (BMIs).

  8. Buck-Boost Control of Four Quadrant Chopper using Symmetrical Impedance Network for Adjustable Speed Drive

    OpenAIRE

    Saswati Swapna Dash; Byamakesh Nayak

    2015-01-01

    This paper proposes buck-boost capabilities of four quadrant chopper for wide range speed control of DC motor drives using symmetrical impedance network called Z-source network. By controlling the shoot through duty ratio from 0 to 0.5 and non-shoot through techniques, the Z-source four quadrant choppers can produce any desired DC voltage across the DC motor. The switching patterns for both buck and boost operations are presented to achieve four modes of operation of DC motor. As a result, th...

  9. The Spectrum Sensing Algorithm Based AdaBoost in Cognitive Radio

    Science.gov (United States)

    Tian, Deyong; Wang, Xin

    To solve the low detection rate of the primary user in the cognitive radio environment, we propose a spectrum sensing method based on AdaBoost in the case of low SNR. In this paper, a set of received signal spectrum features are first calculated and extracted the discriminant feature vector as training samples and testing samples for classification. Finally, we utilize the trained AdaBoost to detect the primary user. Test result shows that the proposed algorithm is not affected by uncertainty factors of noise and has high performance to classification detection compared with ANN, SVM and maximum-minimum eigenvalue (MME).

  10. Practical Implementation of Embedded Controlled Boost Converter for Solar Installation System

    Directory of Open Access Journals (Sweden)

    A. Kalirasu

    2010-08-01

    Full Text Available The solar photovoltaic power has received great attention and experienced impressive progress in the countries all over the world in recent years because of more and more serious energy crisis and environmental pollution. This paper proposes a Embedded controlled boost converter for solar installation system. Boost converter system is simulated using Matlab and it is implemented using embedded controller. The simulation and experimental results of this system are presented and compared. This converter has advantages like improved power factor, fast response and reduced hardware.

  11. Diseño de un convertidor CC-CC doble boost acoplado

    OpenAIRE

    González, Sergio; Puleston, Pablo Federico; Fossas-Colet, Enric

    2012-01-01

    El convertidor de CC a CC doble boost acoplado (C2B) es de interés en aplicaciones emergentes que demandan alto rendimiento y alta relación de conversión, evitando valores extremos del ciclo de trabajo de la llave. El C2B consta de dos convertidores boost en cascada, operando con una sola llave y acoplados magnéticamente a través de sus inductores. Este acoplamiento condiciona fuertemente la relación de conversión del convertidor, dada su dependencia con la corriente de carga. Se analiza su p...

  12. Convertidor DC/DC elevador Boost con control de corriente y de tensión

    OpenAIRE

    Rollón Rodríguez, Javier

    2014-01-01

    Este Trabajo Fin de Máster tiene como objetivo el diseño de un convertidor elevador (Boost) que servirá de base para una posterior construcción, que se utilizará en las prácticas de laboratorio del Departamento de Ingeniería Eléctrica de la Universidad Pública de Navarra. El convertidor Boost es un convertidor DC a DC que obtiene a su salida una tensión continua mayor que a su entrada. Es un tipo de fuente de alimentación conmutada que contiene al menos dos interruptores sem...

  13. Optimization of control parameters of a boost converter for energy harvesting

    Science.gov (United States)

    Tanaka, M.; Hemthavy, P.; Takahashi, K.

    2012-08-01

    In order to maximize the energy efficiency for energy harvesting, a simplified circuit model using a boost converter and a capacitor is proposed. The circuit model allows the analysis of the whole system's theoretical energy efficiency and determination of the optimum control parameters. The optimum duty ratio is determined analytically and the optimum switching period numerically. This is important information for designing a switching controller that achieves both low power consumption and accurate maximum power point tracking. Moreover, the proposed theoretical energy efficiency is helpful for component selection when designing boost converters.

  14. SVR-Boosting ensemble model for electricity price forecasting in electric power market

    Institute of Scientific and Technical Information of China (English)

    ZHOU Dian-min; GAO Lin; GUAN Xiao-hong; GAO Feng

    2008-01-01

    A revised support vector regression (SVR) ensemble model based on boosting algorithm (SVR-Boos-ting) is presented in this paper for electricity price forecasting in electric power market. In the light of charac-the forecasting model to inhibit the learning from abnormal data in electricity price sequence. The results from actual data indicate that, compared with the single support vector regression model, the proposed SVR-Boosting ensemble model is able to enhance the stability of the model output remarkably, acquire higher predicting accu-racy, and possess comparatively satisfactory generalization capability.

  15. Comparison of different boost transformations for the calculation of form factors in relativistic quantum mechanics

    International Nuclear Information System (INIS)

    The effect of different boost expressions, pertinent to the instant, front and point forms of relativistic quantum mechanics, is considered for the calculation of the ground-state form factor of a two-body system in simple scalar models. Results with a Galilean boost as well as an explicitly covariant calculation based on the Bethe-Salpeter approach are given for comparison. It is found that the present so-called point-form calculations of form factors strongly deviate from all the other ones. This suggests that the formalism which underlies them requires further elaboration. A proposition in this sense is made. (author)

  16. Thermal Performance and Efficiency Investigation of Conventional Boost, Z-source and Y-source Converters

    DEFF Research Database (Denmark)

    Gadalla, Brwene Salah Abdelkarim; Schaltz, Erik; Siwakoti, Yam Prasad;

    2016-01-01

    Boost converters are needed in many applications that require the output voltage to be higher than the input voltage. Recently, boost type converters have been attracted by the industrial applications, and hence it has become an extremely hot topic of research. Recently, many researchers proposed...... the impedance source converters with their unique advantages as having a high voltage gain in a small range of duty cycle ratio. However, the thermal behaviour of the semiconductor devices and passive elements in the impedance source converter is an important issue from a reliability point of view and...

  17. Performance of Jet Substructure Techniques and Boosted Object Identification in ATLAS

    CERN Document Server

    Lacey, J; The ATLAS collaboration

    2014-01-01

    ATLAS has implemented and commissioned many new jet substructure techniques to aid in the identification and interpretation of hadronic final states originating from Lorentz-boosted heavy particles produced at the LHC. These techniques include quantum jets, jet charge, jet shapes, quark/gluon, boosted boson and top quark tagging, along with grooming methods such as pruning, trimming, and filtering. These techniques have been validated using the large 2012 ATLAS dataset. Presented here is a summary of the state of the art jet substructure and tagging techniques developed in ATLAS, their performance and recent results.

  18. Reading aloud and solving simple arithmetic calculation intervention (Learning therapy improves inhibition, verbal episodic memory, focus attention, and processing speed in healthy elderly people: Evidence from a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Rui eNouchi

    2016-05-01

    Full Text Available BackgroundPrevious reports have described that simple cognitive training using reading aloud and solving simple arithmetic calculations, so-called learning therapy, can improve executive functions and processing speed in the older adults. Nevertheless, it is not well-known whether learning therapy improve a wide range of cognitive functions or not. We investigated the beneficial effects of learning therapy on various cognitive functions in healthy older adults.MethodsWe used a single-blinded intervention with two groups (learning therapy group: LT and waiting list control group: WL. Sixty-four elderly were randomly assigned to LT or WL. In LT, participants performed reading Japanese aloud and solving simple calculations training tasks for 6 months. WL did not participate in the intervention. We measured several cognitive functions before and after 6 months intervention periods.ResultsCompared to WL, results revealed that LT improved inhibition performance in executive functions (Stroop: LT (Mean = 3.88 vs. WL (Mean = 1.22, adjusted p =.013 and reverse Stroop LT (Mean = 3.22 vs. WL (Mean = 1.59, adjusted p =.015, verbal episodic memory (logical memory: LT (Mean = 4.59 vs. WL (Mean = 2.47, adjusted p =.015, focus attention(D-CAT: LT (Mean = 2.09 vs. WL (Mean = -0.59, adjusted p =.010 and processing speed compared to the waiting list control group (digit symbol coding: LT (Mean = 5.00 vs. WL (Mean = 1.13, adjusted p =.015 and symbol search: LT (Mean = 3.47 vs. WL (Mean = 1.81, adjusted p =.014.DiscussionThis RCT can showed the benefit of learning therapy on inhibition of executive functions, verbal episodic memory, focus attention, and processing speed in healthy elderly people. Our results were discussed under overlapping hypothesis.Trial registrationThis trial was registered in The University Hospital Medical Information Network Clinical Trials Registry (UMIN000006998.

  19. Beneficial effects of reading aloud and solving simple arithmetic calculations (learning therapy on a wide range of cognitive functions in the healthy elderly: study protocol for a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Nouchi Rui

    2012-04-01

    Full Text Available Abstract Background Almost all cognitive functions decline with age. Results of previous studies have shown that cognitive training related to everyday life (reading aloud and solving simple arithmetic calculations, namely learning therapy, can improve two cognitive function (executive functions and processing speed in elderly people. However, it remains unclear whether learning therapy engenders improvement of various cognitive functions or not. We investigate the impact of learning therapy on various cognitive functions (executive functions, episodic memory, short-term memory, working memory, attention, reading ability, and processing speed in healthy older adults. Methods We use a single-blinded intervention with two parallel groups (a learning therapy group and a waiting list control group. Testers are blind to the study hypothesis and the group membership of participants. Through an advertisement in local newspaper, 64 healthy older adults are recruited. They will be assigned randomly to a learning therapy group or a waiting list control group. In the learning therapy group, participants are required to perform two cognitive tasks for 6 months: reading Japanese aloud and solving simple calculations. The waiting list group does not participate in the intervention. The primary outcome measure is the Stroop test score: a measure of executive function. Secondary outcome measures are assessments including the following: verbal fluency task, logical memory, first and second names, digit span forward, digit span backward, Japanese reading test, digit cancellation task, digit symbol coding, and symbol search. We assess these outcome measures before and after the intervention. Discussion This report is the first study which investigates the beneficial effects of learning therapy on a wide range of cognitive functions of elderly people. Our study provides sufficient evidence of learning therapy effectiveness. Most cognitive functions, which are

  20. 基于有声思维法的中西方思维差异研究%A Study on Discrepancies between Chinese and English Thinking Pattern Based on Think-aloud Method

    Institute of Scientific and Technical Information of China (English)

    苏淼

    2014-01-01

    作为一种实证性研究,有声思维借鉴了认知心理学的研究模式,试图通过实证,探究大脑的思维认知过程。本文采用“有声思维”的方法收集中外十名大学生在母语写作过程中的数据,并从选词、句型和语篇结构方面对数据进行整理和分析,得出中英思维差异主要体现在三大类:形合和意合、主观型和客观型、归纳型和演绎型。%As an empirical study, the think-aloud method learns from the research pattern of cogni-tive psychology, and tries to explore the cognitive process of thinking by empirical study. By using the method of think-aloud, this paper collects data from ten subjects who are university students with English and Chinese as their mother tongue respectively when they are writing. Through data reduction and analy-sis of word-choice, sentence pattern and discourse structure;there are mainly three types of discrepancies:hypostasis and parataxis, subjective thinking and objective thinking as well as induction and deduction. This paper aims to explore what influence different thinking pattern and process have on writing strategies and writing unit choosing.