WorldWideScience

Sample records for phase start time

  1. Effects of various intake valve timings and spark timings on combustion, cyclic THC and NOX emissions during cold start phase with idle operation in CVVT engine

    International Nuclear Information System (INIS)

    Choi, Kwan Hee; Lee, Hyung Min; Hwang, In Goo; Myung, Cha Lee; Park, Sim Soo

    2008-01-01

    In a gasoline SI engine, valve events and spark timings put forth a major influence on overall efficiency, fuel economy, and exhaust emissions. Residual gases controlled by the valve overlap can be used to reduce NOx emissions and the spark retardation technique can be used to improve raw THC emissions and catalyst light-off performance during the cold start phase. This paper investigated the behaviors of the engine and its combustion characteristics with various intake valve timings and spark timings during the fast idle condition and cold start. And cyclic THC and NOx emissions were measured at the exhaust port and their formation mechanisms were examined with fast response gas analyzers. As a result, THCs and NOx were reduced by 35% and 23% with optimizing valve overlap and spark advance during the cold transient start phase. Consequently, the valve events and ignition timings were found to significantly affect combustion phenomena and cold-start emissions

  2. Key parameters of the swimming start and their relationship to start performance.

    Science.gov (United States)

    Tor, Elaine; Pease, David L; Ball, Kevin A

    2015-01-01

    The swimming start is typically broken into three sub-phases; on-block, flight, and underwater phases. While overall start performance is highly important to elite swimming, the contribution of each phase and important technical components within each phase, particularly with the new kick-start technique, has not been established. The aim of this study was to identify technical factors associated with overall start performance, with a particular focus on the underwater phase. A number of parameters were calculated from 52 starts performed by elite freestyle and butterfly swimmers. These parameters were split into above-water and underwater groupings, before factor analysis was used to reduce parameter numbers for multiple regression. For the above-water phases, 81% of variance in start performance was accounted for by take-off horizontal velocity. For the underwater water phase, 96% of variance was accounted for with time underwater in descent, time underwater in ascent and time to 10 m. Therefore, developing greater take-off horizontal velocity and focussing on the underwater phase by finding the ideal trajectory will lead to improved start performance.

  3. Scheduling with target start times

    NARCIS (Netherlands)

    Hoogeveen, J.A.; Velde, van de S.L.; Klein Haneveld, W.K.; Vrieze, O.J.; Kallenberg, L.C.M.

    1997-01-01

    We address the single-machine problem of scheduling n independent jobs subject to target start times. Target start times are essentially release times that may be violated at a certain cost. The goal is to minimize an objective function that is composed of total completion time and maximum

  4. Later Start, Longer Sleep: Implications of Middle School Start Times

    Science.gov (United States)

    Temkin, Deborah A.; Princiotta, Daniel; Ryberg, Renee; Lewin, Daniel S.

    2018-01-01

    Background: Although adolescents generally get less than the recommended 9 hours of sleep per night, research and effort to delay school start times have generally focused on high schools. This study assesses the relation between school start times and sleep in middle school students while accounting for potentially confounding demographic…

  5. High Time Resolution Measurements of VOCs from Vehicle Cold Starts: The Air Toxic Cold Start Pulse

    Science.gov (United States)

    Jobson, B. T.; Huangfu, Y.; Vanderschelden, G. S.

    2017-12-01

    Pollutants emitted during motor vehicle cold starts, especially in winter in some climates, is a significant source of winter time air pollution. While data exist for CO, NO, and total hydrocarbon emissions from federal testing procedures for vehicle emission certification, little is known about the emission rates of individual volatile organic compounds, in particular the air toxics benzene, formaldehyde, and acetaldehyde. Little is known about the VOC speciation and temperature dependence for cold starts. The US EPA vehicle emission model MOVES assumes that cold start emissions have the same speciation profile as running emissions. We examined this assumption by measuring cold start exhaust composition for 4 vehicles fueled with E10 gasoline over a temperature range of -4°C to 10°C in winter of 2015. The extra cold start emissions were determined by comparison with emissions during engine idling. In addition to CO and NOx measurements a proton transfer reaction mass spectrometer was used to measure formaldehyde, acetaldehyde, benzene, toluene, and C2-alkylbenzenes at high time resolution to compare with the cold start emission speciation profiles used in the EPA MOVES2014 model. The results show that after the vehicle was started, CO mixing ratios can reach a few percent of the exhaust and then drop to several ppmv within 2 minutes of idling, while NOx showed different temporal behaviors among the four vehicles. VOCs displayed elevated levels during cold start and the peak mixing ratios can be two orders higher than idling phase levels. Molar emission ratios relative to toluene were used to compare with the emission ratio used in MOVES2014 and we found the formaldehyde-to-toluene emission ratio was about 0.19, which is 5 times higher than the emission ratio used in MOVES2014 and the acetaldehyde-to-toluene emission ratios were 0.86-0.89, which is 8 times higher than the ones in MOVES2014. The C2-alkylbenzene-to-toluene ratio agreed well with moves. Our results

  6. Split-phase motor running as capacitor starts motor and as capacitor run motor

    Directory of Open Access Journals (Sweden)

    Yahaya Asizehi ENESI

    2016-07-01

    Full Text Available In this paper, the input parameters of a single phase split-phase induction motor is taken to investigate and to study the output performance characteristics of capacitor start and capacitor run induction motor. The value of these input parameters are used in the design characteristics of capacitor run and capacitor start motor with each motor connected to rated or standard capacitor in series with auxiliary winding or starting winding respectively for the normal operational condition. The magnitude of capacitor that will develop maximum torque in capacitor start motor and capacitor run motor are investigated and determined by simulation. Each of these capacitors is connected to the auxiliary winding of split-phase motor thereby transforming it into capacitor start or capacitor run motor. The starting current and starting torque of the split-phase motor (SPM, capacitor run motor (CRM and capacitor star motor (CSM are compared for their suitability in their operational performance and applications.

  7. Single phase induction motor with starting performance

    Energy Technology Data Exchange (ETDEWEB)

    Popescu, M.; Demeter, E. [Research Institute for Electrical Machines, ICPE-ME, Bucharest (Romania); Navrapescu, V. [University `Politehnica` Bucharest, Electrical Engineering Faculty Splaiul Independentei, Bucharest (Romania)

    1997-12-31

    The paper presents problems related to a special type of single phase induction motor. The main novelty consists in the use of a conducting (aluminium casted) shell distributed on the periferic region of the rotor. As a result the starting performance, as well as the rated ones, is much improved in comparison with the conventional construction. (orig.) 4 refs.

  8. The start up as a phase of architectural design process.

    Science.gov (United States)

    Castro, Iara Sousa; Lima, Francisco de Paula Antunes; Duarte, Francisco José de Castro Moura

    2012-01-01

    Alterations made in the architectural design can be considered as a continuous process, from its conception to the moment a built environment is already in use. This article focuses on the "moving phase", which is the initial moment of the environment occupation and the start-up of services. It aims to show that the continuity of ergonomics interventions during the "moving phase" or start up may reveal the built environment inadequacies; clearly showing needs not met by the design and allowing making instant decisions to solve non-foreseen problems. The results have revealed some lessons experienced by users during a critical stage not usually included in the design process.

  9. Sleep, sleepiness and school start times: a preliminary study.

    Science.gov (United States)

    Dexter, Donn; Bijwadia, Jagdeep; Schilling, Dana; Applebaugh, Gwendolyn

    2003-01-01

    High school students are reported to be excessively sleepy, resulting in decreased academic performance, increased psycho-social problems and increased risk of morbidity and mortality from accidents. Early school start times have been noted to contribute to this problem. This report attempts to confirm the relationship of early school start times with decreased sleep and increased sleepiness. We examined sophomore and junior students in 2 local high schools with different start times and measured the amount of time slept and sleepiness. We found that students at the early start school reported reduced sleep time and more sleepiness than their counterparts at the later starting school. Early school start times are associated with student reports of less sleep and increased sleepiness. Further studies in larger groups are recommended in view of the potential significant impact of sleep deprivation in this age group.

  10. Single start multiple stop time digitizer

    International Nuclear Information System (INIS)

    Deshpande, P.A.; Mukhopadhyay, P.K.; Gopalakrishnan, K.R.

    1997-01-01

    A single start multiple stop time digitizer has been developed which can digitize the time between a start pulse and multiple stop pulses. The system has been designed as a PC add on card. The resolution of the instrument is 10 nSecs and the maximum length of time that it can measure is 1.28 milliseconds. Apart from time digitization, it can also resolve the height of the incoming pulses into 64 levels. After each input pulse the system dead time is less than 300 nSecs. The driver software for this card has been developed on DOS platform. It uses graphical user interface to provide a user friendly environment. The system is intended to be used in time of flight mass spectroscopy experiments. It can also be used for time of flight experiments in nuclear physics. (author). 2 figs

  11. Split-phase motor running as capacitor starts motor and as capacitor run motor

    OpenAIRE

    Yahaya Asizehi ENESI; Jacob TSADO; Mark NWOHU; Usman Abraham USMAN; Odu Ayo IMORU

    2016-01-01

    In this paper, the input parameters of a single phase split-phase induction motor is taken to investigate and to study the output performance characteristics of capacitor start and capacitor run induction motor. The value of these input parameters are used in the design characteristics of capacitor run and capacitor start motor with each motor connected to rated or standard capacitor in series with auxiliary winding or starting winding respectively for the normal operational condition. The ma...

  12. School start times for adolescents.

    Science.gov (United States)

    2014-09-01

    The American Academy of Pediatrics recognizes insufficient sleep in adolescents as an important public health issue that significantly affects the health and safety, as well as the academic success, of our nation's middle and high school students. Although a number of factors, including biological changes in sleep associated with puberty, lifestyle choices, and academic demands, negatively affect middle and high school students' ability to obtain sufficient sleep, the evidence strongly implicates earlier school start times (ie, before 8:30 am) as a key modifiable contributor to insufficient sleep, as well as circadian rhythm disruption, in this population. Furthermore, a substantial body of research has now demonstrated that delaying school start times is an effective countermeasure to chronic sleep loss and has a wide range of potential benefits to students with regard to physical and mental health, safety, and academic achievement. The American Academy of Pediatrics strongly supports the efforts of school districts to optimize sleep in students and urges high schools and middle schools to aim for start times that allow students the opportunity to achieve optimal levels of sleep (8.5-9.5 hours) and to improve physical (eg, reduced obesity risk) and mental (eg, lower rates of depression) health, safety (eg, drowsy driving crashes), academic performance, and quality of life. Copyright © 2014 by the American Academy of Pediatrics.

  13. Start Later, Sleep Later: School Start Times and Adolescent Sleep in Homeschool vs. Public/Private School Students

    Science.gov (United States)

    Meltzer, Lisa J.; Shaheed, Keisha; Ambler, Devon

    2014-01-01

    Homeschool students provide a naturalistic comparison group for later/flexible school start times. This study compared sleep patterns and sleep hygiene for homeschool students and public/private school students (grades 6-12). Public/private school students (n=245) and homeschool students (n=162) completed a survey about sleep patterns and sleep hygiene. Significant school group differences were found for weekday bedtime, wake time, and total sleep time, with homeschool students waking later and obtaining more sleep. Homeschool students had later school start times, waking at the same time that public/private school students were starting school. Public/private school students had poorer sleep hygiene practices, reporting more homework and use of technology in the hour before bed. Regardless of school type, technology in the bedroom was associated with shorter sleep duration. Later school start times may be a potential countermeasure for insufficient sleep in adolescents. Future studies should further examine the relationship between school start times and daytime outcomes, including academic performance, mood, and health. PMID:25315902

  14. Applying behavioral insights to delay school start times.

    Science.gov (United States)

    Kohl Malone, Susan; Ziporyn, Terra; Buttenheim, Alison M

    2017-12-01

    Healthy People 2020 established a national objective to increase the proportion of 9th-to-12th-grade students reporting sufficient sleep. A salient approach for achieving this objective is to delay middle and high school start times. Despite decades of research supporting the benefits of delayed school start times on adolescent sleep, health, and well-being, progress has been slow. Accelerating progress will require new approaches incorporating strategies that influence how school policy decisions are made. In this commentary, we introduce four strategies that influence decision-making processes and demonstrate how they can be applied to efforts aimed at changing school start time policies. Copyright © 2017 National Sleep Foundation. All rights reserved.

  15. School start times and teenage driver motor vehicle crashes.

    Science.gov (United States)

    Foss, Robert D; Smith, Richard L; O'Brien, Natalie P

    2018-04-26

    Shifting school start times to 8:30 am or later has been found to improve academic performance and reduce behavior problems. Limited research suggests this may also reduce adolescent driver motor vehicle crashes. A change in the school start time from 7:30 am to 8:45 am for all public high schools in one North Carolina county presented the opportunity to address this question with greater methodologic rigor. We conducted ARIMA interrupted time-series analyses to examine motor vehicle crash rates of high school age drivers in the intervention county and 3 similar comparison counties with comparable urban-rural population distribution. To focus on crashes most likely to be affected, we limited analysis to crashes involving 16- & 17-year-old drivers occurring on days when school was in session. In the intervention county, there was a 14% downward shift in the time-series following the 75 min delay in school start times (p = .076). There was no change approaching statistical significance in any of the other three counties. Further analysis indicated marked, statistically significant shifts in hourly crash rates in the intervention county, reflecting effects of the change in school start time on young driver exposure. Crashes from 7 to 7:59 am decreased sharply (-25%, p = .008), but increased similarly from 8 to 8:59 am (21%, p = .004). Crashes from 2 to 2:59 pm declined dramatically (-48%, p = .000), then increased to a lesser degree from 3 to 3:59 pm (32%, p = .024) and non-significantly from 4 to 4:59 (19%, p = .102). There was no meaningful change in early morning or nighttime crashes, when drowsiness-induced crashes might have been expected to be most common. The small decrease in crashes among high school age drivers following the shift in school start time is consistent with the findings of other studies of teen driver crashes and school start times. All these studies, including the present one, have limitations, but the similar

  16. Later School Start Times: What Informs Parent Support or Opposition?

    Science.gov (United States)

    Dunietz, Galit Levi; Matos-Moreno, Amilcar; Singer, Dianne C; Davis, Matthew M; O'Brien, Louise M; Chervin, Ronald D

    2017-07-15

    To investigate parental knowledge about adolescent sleep needs, and other beliefs that may inform their support for or objection to later school start times. In 2014, we conducted a cross-sectional, Internet-based survey of a nationally representative sample of parents as part of the C.S. Mott Children's Hospital National Poll on Children's Health. Parents with teens aged 13-17 years reported their children's sleep patterns and school schedules, and whether the parents supported later school start times (8:30 am or later). Responses associated with parental support of later school start times were examined with logistic regression analysis. Overall, 88% of parents reported school start times before 8:30 am, and served as the analysis sample (n = 554). In this group, 51% expressed support for later school start times. Support was associated with current school start times before 7:30 am (odds ratio [OR] = 3.1 [95% confidence interval (CI) 1.2, 8.4]); parental opinion that their teen's current school start time was "too early" (OR = 3.8 [1.8, 7.8]); and agreement with American Academy of Pediatrics recommendations about school start times (OR = 4.7 [2.2, 10.1]). Support also was associated with anticipation of improved school performance (OR = 3.0 [1.5, 5.9]) or increased sleep duration (OR = 4.0 [1.8, 8.9]) with later school start times. Conversely, parents who anticipated too little time for after-school activities (OR = 0.5 [0.3, 0.9]) and need for different transportation plans (OR = 0.5 [0.2, 0.9]) were often less supportive. Parental education about healthy sleep needs and anticipated health benefits may increase their support for later school start times. Educational efforts should also publicize the positive experiences of communities that have made this transition, with regard to limited adverse effect on after-school activity schedules and transportation. © 2017 American Academy of Sleep Medicine

  17. Start time delays in operating room: Different perspectives

    Directory of Open Access Journals (Sweden)

    Babita Gupta

    2011-01-01

    Full Text Available Background: Healthcare expenditure is a serious concern, with escalating costs failing to meet the expectations of quality care. The treatment capacities are limited in a hospital setting and the operating rooms (ORs. Their optimal utilization is vital in efficient hospital management. Starting late means considerable wait time for staff, patients and waste of resources. We planned an audit to assess different perspectives of the residents in surgical specialities and anesthesia and OR staff nurses so as to know the causative factors of operative delay. This can help develop a practical model to decrease start time delays in operating room (ORs. Aims: An audit to assess different perspectives of the Operating room (OR staff with respect to the varied causative factors of operative delay in the OR. To aid in the development of a practical model to decrease start time delays in ORs and facilitate on-time starts at Jai Prakash Narayan Apex Trauma centre (JPNATC, All India Institute of Medical Sciences (AIIMS, New Delhi. Methods: We prepared a questionnaire seeking the five main reasons of delay as per their perspective. Results: The available data was analysed. Analysis of the data demonstrated the common causative factors in start time operative delays as: a lack of proper planning, deficiencies in team work, communication gap and limited availability of trained supporting staff. Conclusions: The preparation of the equipment and required material for the OR cases must be done well in advance. Utilization of newer technology enables timely booking and scheduling of cases. Improved inter-departmental coordination and compliance with preanesthetic instructions needs to be ensured. It is essential that the anesthesiologists perform their work promptly, well in time . and supervise the proceedings as the OR manager. This audit is a step forward in defining the need of effective OR planning for continuous quality improvement.

  18. Pre-start timing information is used to set final linear speed in a C-start manoeuvre.

    Science.gov (United States)

    Reinel, Caroline; Schuster, Stefan

    2014-08-15

    In their unique hunting behaviour, archerfish use a complex motor decision to secure their prey: based solely on how dislodged prey initially falls, they select an adapted C-start manoeuvre that turns the fish right towards the point on the water surface where their prey will later land. Furthermore, they take off at a speed that is set so as to arrive in time. We show here that the C-start manoeuvre and not subsequent tail beating is necessary and sufficient for setting this adaptive level of speed. Furthermore, the C-start pattern is adjusted to independently determine both the turning angle and the take-off speed. The selection of both aspects requires no a priori information and is done based on information sampled from the onset of target motion until the C-start is launched. Fin strokes can occur right after the C-start manoeuvre but are not required to fine-tune take-off speed, but rather to maintain it. By probing the way in which the fish set their take-off speed in a wide range of conditions in which distance from the later catching point and time until impact varied widely and unpredictably, we found that the C-start manoeuvre is programmed based on pre-C-start estimates of distance and time until impact. Our study hence provides the first evidence for a C-start that is fine-tuned to produce an adaptive speed level. © 2014. Published by The Company of Biologists Ltd.

  19. Balance of the first 1300MW units start-up phase

    International Nuclear Information System (INIS)

    Meclot, M.; Lemagny, M.; Lavogiez, M.

    1985-01-01

    The program of tests is briefly recalled. Then, a balance of the incident cards is presented. After a recall of the lessons to be drawn from the start-up phase, a comparative examination of the 1300 and 900 unit availability is presented for the first operating year [fr

  20. School Start Time and Teen Sleep.

    Science.gov (United States)

    Wahlstrom, Kyla L.

    2000-01-01

    Sleep studies have shown that teenagers' internal clocks are incompatible with most high schools' early hours. Research in two Minnesota districts indicates that later school starting times can benefit teens and everyone dealing with them. Student participation in sports and other afterschool activities remained high. (MLH)

  1. School start time effects on adolescent learning and academic performance, emotional health and behaviour.

    Science.gov (United States)

    Wahlstrom, Kyla L; Owens, Judith A

    2017-11-01

    The investigation of the relationship between the time of day that school begins and the effects it could have on students began in the mid-1990s. Since that time, many articles have been written either for the medical literature or the educational literature. This review is intended to bridge that gap by examining together the findings for both academic and health outcomes, exploring what we know and what is needed in further investigation. Teens who are sleep deficient (defined as obtaining less than 8 h per night) because of early starting time for their school are much more likely to engage in risky behaviours, such as drug, cigarette and alcohol use, have significant feelings of depression, get lower grades and are at greater risk for car crashes. Many studies of academic performance and later school start time indicate benefits, although further research is needed to understand the related mechanisms that contribute to improvements in achievement. Recent research in adolescent sleep and outcomes is being shaped by not only measuring sleep duration, but also examining the timing in which sleep occurs. Early school starting time for middle and high students has a clear, deleterious effect on their health and well being. Most recently, sleep deficit in teens is being viewed as a public health issue that needs a wider discussion about its impact and it necessitates improved public education about the sleep phase shift that occurs during adolescence.

  2. Measuring the phase difference in network and residual voltages under the GTsN-195M pump self-starting

    International Nuclear Information System (INIS)

    Druba, V.V.; Druba, T.A.; Reznik, V.R.

    1989-01-01

    Determination of time dependence of phase difference of residual voltage on motor windings of the main circulation pumps (MCP) and voltage of power supply section under MCP self-starting under conditions of short-time breaks in electric power supply is one of the main problems to which reliability and safety of NPP operation is related. A method to measure this dependence in real conditions in case of MCP free run-out and run-out in generating mode is suggested. The method considered is used for tests of the Kalinin NPP-2 MCP-195M self-starting. Analysis of run-out curves in the case of a break in MCP power supply for 1.8 s shows that the most favourable conditions for MCP self-starting are 0.63±0.03 s after de-energizing. 2 refs.; 3 figs.; 1 tab

  3. Hybrid I-f starting and observer-based Ssnsorless control of single-phase BLDC-PM motor drives

    DEFF Research Database (Denmark)

    Iepure, Liviu Ioan; Boldea, Ion; Blaabjerg, Frede

    2012-01-01

    A motion sensorless control for single-phase permanent magnet brushless dc motor based on an I-f starting sequence and a real-time permanent magnet flux estimation is proposed here. The special calculation for extracting the position and speed used here implies the generating of an orthogonal flux...... system, the atan2 trigonometric function, and a phase-locked loop observer. The influence of the permanent magnet flux harmonic content is presented by analytical expressions and digital simulations. The proposed sensorless control is validated by complete experimental results on a commercial small high......-speed blower-motor (40 W, 10 krpm, 12 Vdc)....

  4. Predicting the start and maximum amplitude of solar cycle 24 using similar phases and a cycle grouping

    International Nuclear Information System (INIS)

    Wang Jialong; Zong Weiguo; Le Guiming; Zhao Haijuan; Tang Yunqiu; Zhang Yang

    2009-01-01

    We find that the solar cycles 9, 11, and 20 are similar to cycle 23 in their respective descending phases. Using this similarity and the observed data of smoothed monthly mean sunspot numbers (SMSNs) available for the descending phase of cycle 23, we make a date calibration for the average time sequence made of the three descending phases of the three cycles, and predict the start of March or April 2008 for cycle 24. For the three cycles, we also find a linear correlation of the length of the descending phase of a cycle with the difference between the maximum epoch of this cycle and that of its next cycle. Using this relationship along with the known relationship between the rise-time and the maximum amplitude of a slowly rising solar cycle, we predict the maximum SMSN of cycle 24 of 100.2 ± 7.5 to appear during the period from May to October 2012. (letters)

  5. Indigenous microbial capability in solid manure residues to start-up solid-phase anaerobic digesters.

    Science.gov (United States)

    Yap, S D; Astals, S; Jensen, P D; Batstone, D J; Tait, S

    2017-06-01

    Batch solid-phase anaerobic digestion is a technology for sustainable on-farm treatment of solid residues, but is an emerging technology that is yet to be optimised with respect to start-up and inoculation. In the present study, spent bedding from two piggeries (site A and B) were batch digested at total solids (TS) concentration of 5, 10 and 20% at mesophilic (37°C) and thermophilic (55°C) temperatures, without adding an external inoculum. The results showed that the indigenous microbial community present in spent bedding was able to recover the full methane potential of the bedding (140±5 and 227±6L CH 4 kgVS fed -1 for site A and B, respectively), but longer treatment times were required than for digestion with an added external inoculum. Nonetheless, at high solid loadings (i.e. TS level>10%), the digestion performance was affected by chemical inhibition due to ammonia and/or humic acid. Thermophilic temperatures did not influence digestion performance but did increase start-up failure risk. Further, inoculation of residues from the batch digestion to subsequent batch enhanced start-up and achieved full methane potential recovery of the bedding. Inoculation with liquid residue (leachate) was preferred over a solid residue, to preserve treatment capacity for fresh substrate. Overall, the study highlighted that indigenous microbial community in the solid manure residue was capable of recovering full methane potential and that solid-phase digestion was ultimately limited by chemical inhibition rather than lack of suitable microbial community. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Determination of Uncalibrated Phase Delays for Real-Time PPP

    Science.gov (United States)

    Hinterberger, Fabian; Weber, Robert; Huber, Katrin; Lesjak, Roman

    2014-05-01

    Today PPP is a well-known technique of GNSS based positioning used for a wide range of post-processing applications. Using observations of a single GNSS receiver and applying precise orbit and clock information derived from global GNSS networks highly precise positions can be obtained. The atmospheric delays are usually mitigated by linear combination (ionosphere) and parameter estimation (troposphere). Within the last years also the demand for real-time PPP increased. In 2012, the IGS real-time working group started a pilot project to broadcast real-time precise orbits and clock correction streams. Nevertheless, real-time PPP is in its starting phase and currently only few applications make use of the technique although SSR-Messages are already implemented in RTCM3.1. The problems of still limited accuracy compared to Network-RTK as well as long convergence times might be solved by almost instantaneous integer ambiguity resolution at zero-difference level which is a major topic of current scientific investigations. Therefore a national consortium has carried out over the past 2 years the research project PPP-Serve (funded by the Austrian Research Promotion Agency - FFG), which aimed at the development of appropriate algorithms for real-time PPP with special emphasis on the ambiguity resolution of zero-difference observations. We have established a module which calculates based on GPS-reference station data-streams of a dense network (obtained from IGS via BKG) so-called wide-lane and narrow-lane satellite specific calibration phase delays. While the wide-lane phase delays are almost stable over longer periods, the estimation of narrow-lane phase delays has to be re-established every 24 hours. These phase-delays are submitted via a real-time module to the rover where they are used for point positioning via a PPP-model. This presentation deals with the process and obstacles of calculating the wide-lane and narrow-lane phase-delays (based on SD -observations between

  7. Operative Start Time Does Not Affect Post-Operative Infection Risk.

    Science.gov (United States)

    Guidry, Christopher A; Davies, Stephen W; Willis, Rhett N; Dietch, Zachary C; Shah, Puja M; Sawyer, Robert G

    2016-10-01

    Surgical care is delivered 24 h a day at most institutions. Alarmingly, some authors have found that certain operative start times are associated with greater morbidity and mortality rates. This effect has been noted in both the public and private sector. Although some of these differences may be related to process, they may also be caused by the human circadian rhythm and corresponding changes in host defenses. We hypothesized that the time of day of an operation would impact the frequency of certain post-operative outcomes significantly. Cases at a single tertiary-care center reported to the American College of Surgeons National Surgical Quality Improvement Program over a 10-year period were identified. Operative start times were divided into six-hour blocks, with 6 am to noon serving as the reference. Standard univariable techniques were applied. Multivariable logistic regression with mixed effects modeling then was used to determine the relation between operative start times and infectious outcomes, controlling for surgeon clustering. Statistical significance was set at p operative infectious complication. Seventy percent of these infections (n = 1,506) were surgical site infections. On univariable analysis considering all cases, nighttime and evening operations had higher rates of post-operative infections than those in performed during the day (9.1% from 6 am to noon; 9.7% from noon to 6 pm; 14.8% from 6 pm to midnight; and 14.4% from midnight to 6 am; p operative start time was not associated with the risk of post-operative infection, even when emergency cases were considered independently. Our data suggest that operative start times have no correlation with post-operative infectious complications. Further work is required to identify the source of the time-dependent outcome variability observed in previous studies.

  8. Later Start Time for Teens Improves Grades, Mood, and Safety

    Science.gov (United States)

    Wahlstrom, Kyla L.

    2017-01-01

    A recent study by the University of Minnesota looked at eight high schools across the U.S. that chose later start times, from 8:00 a.m. to 8:55 a.m. The study found significant decreases in absences and tardiness as well as greater academic benefits for schools with the latest start times. Among the 9,395 students in the study, those who slept…

  9. Improving ADM1 model to simulate anaerobic digestion start-up with inhibition phase based on cattle slurry

    International Nuclear Information System (INIS)

    Normak, A.; Suurpere, J.; Suitso, I.; Jõgi, E.; Kokin, E.; Pitk, P.

    2015-01-01

    The Anaerobic Digestion Model No.1 (ADM1) was improved to simulate an anaerobic digestion start-up phase. To improve the ADM1, a combined hydrolysis equation was used based on the Contois model of bacterial growth and the function of hydrolysis inhibition by VFA. The start-up with fresh cattle slurry was carried out in a pilot-scale reactor to calibrate the chosen parameters of the ADM1. The important aspects of model calibration were hydrolysis rate, the number of anaerobic microbes in cattle slurry, and the growth rate of bacteria. Good simulation results were achieved after calibration for the independent start-up test with pre-conditioned cattle slurry. - Highlights: • Improved ADM1 can be used for simulation of reactor start-up with inhibition phase. • The hydrolysis rate had a decreased value in case of high VFA concentration or low number of hydrolytic bacteria. • Hydrolysis inhibitory threshold value of 9.85 g L −1 was obtained for VFA. • Start-up with pre-conditioned cattle slurry had a relatively short inhibition phase

  10. Biomechanical Analysis of the Swim-Start: A Review

    Directory of Open Access Journals (Sweden)

    Julien Vantorre, Didier Chollet, Ludovic Seifert

    2014-06-01

    Full Text Available This review updates the swim-start state of the art from a biomechanical standpoint. We review the contribution of the swim-start to overall swimming performance, the effects of various swim-start strategies, and skill effects across the range of swim-start strategies identified in the literature. The main objective is to determine the techniques to focus on in swimming training in the contemporary context of the sport. The phases leading to key temporal events of the swim-start, like water entry, require adaptations to the swimmer’s chosen technique over the course of a performance; we thus define the swim-start as the moment when preparation for take-off begins to the moment when the swimming pattern begins. A secondary objective is to determine the role of adaptive variability as it emerges during the swim-start. Variability is contextualized as having a functional role and operating across multiple levels of analysis: inter-subject (expert versus non-expert, inter-trial or intra-subject (through repetitions of the same movement, and inter-preference (preferred versus non-preferred technique. Regarding skill effects, we assume that swim-start expertise is distinct from swim stroke expertise. Highly skilled swim-starts are distinguished in terms of several factors: reaction time from the start signal to the impulse on the block, including the control and regulation of foot force and foot orientation during take-off; appropriate amount of glide time before leg kicking commences; effective transition from leg kicking to break-out of full swimming with arm stroking; overall maximal leg and arm propulsion and minimal water resistance; and minimized energy expenditure through streamlined body position. Swimmers who are less expert at the swim-start spend more time in this phase and would benefit from training designed to reduce: (i the time between reaction to the start signal and impulse on the block, and (ii the time in transition (i

  11. Delayed-Start Analyses in the Phase 3 Solanezumab EXPEDITION3 Study in Mild Alzheimer's Disease.

    Science.gov (United States)

    Liu-Seifert, H; Case, M G; Andersen, S W; Holdridge, K C; Aisen, P S; Kollack-Walker, S; Siemers, E

    2018-01-01

    A delayed-start design has been proposed to assess a potential disease-modifying effect in investigational drugs for Alzheimer's disease that target the underlying disease process. We extended this methodology to recently obtained data from the EXPEDITION3. EXPEDITION3 was a Phase 3, double-blind study with participants randomized to solanezumab (400 mg) or placebo every 4 weeks for 80 weeks, with an optional extension of active treatment. The delayed-start analysis was designed to determine if a statistically significant treatment difference established during the placebo-controlled period is maintained (at predefined level) during the delayed-start period, which would suggest the active drug has a disease-modifying effect. The delayed-start analysis was assessed across multiple efficacy measures, and includes data from baseline in the placebo-controlled period and up to 9 months in the delayed-start period. No significant difference was observed between the placebo and solanezumab treatment groups at the end of the placebo-controlled period for the Alzheimer's Disease Assessment Scale-Cognitive 14-item subscale. A significant treatment difference was observed at the end of the placebo-controlled period for the Alzheimer's Disease Cooperative Study-Activities of Daily Living instrumental items, an effect also seen at 6 months in the delayed-start period, and the noninferiority criterion was met. No other efficacy measures met these criteria. Delayed-start statistical methodology was used to understand the longitudinal outcomes in EXPEDITION3 and its extension. The small treatment differences observed at the end of the placebo-controlled phase prevented adequate assessment of any putative disease modifying effect.

  12. Model based analysis of the time scales associated to pump start-ups

    Energy Technology Data Exchange (ETDEWEB)

    Dazin, Antoine, E-mail: antoine.dazin@lille.ensam.fr [Arts et métiers ParisTech/LML Laboratory UMR CNRS 8107, 8 bld Louis XIV, 59046 Lille cedex (France); Caignaert, Guy [Arts et métiers ParisTech/LML Laboratory UMR CNRS 8107, 8 bld Louis XIV, 59046 Lille cedex (France); Dauphin-Tanguy, Geneviève, E-mail: genevieve.dauphin-tanguy@ec-lille.fr [Univ Lille Nord de France, Ecole Centrale de Lille/CRISTAL UMR CNRS 9189, BP 48, 59651, Villeneuve d’Ascq cedex F 59000 (France)

    2015-11-15

    Highlights: • A dynamic model of a hydraulic system has been built. • Three periods in a pump start-up have been identified. • The time scales of each period have been estimated. • The parameters affecting the rapidity of a pump start-up have been explored. - Abstract: The paper refers to a non dimensional analysis of the behaviour of a hydraulic system during pump fast start-ups. The system is composed of a radial flow pump and its suction and delivery pipes. It is modelled using the bond graph methodology. The prediction of the model is validated by comparison to experimental results. An analysis of the time evolution of the terms acting on the total pump pressure is proposed. It allows for a decomposition of the start-up into three consecutive periods. The time scales associated with these periods are estimated. The effects of parameters (angular acceleration, final rotation speed, pipe length and resistance) affecting the start-up rapidity are then explored.

  13. Relationships between school start time, sleep duration, and adolescent behaviors.

    Science.gov (United States)

    Wahlstrom, Kyla L; Berger, Aaron T; Widome, Rachel

    2017-06-01

    The objectives were 2-fold: (1) to examine how high school start times relate to adolescent sleep duration, and (2) to test associations between sleep duration and mental health- and substance use-related issues and behaviors in teens. This study examines selected questions from survey data collected between 2010 and 2013 high school students. Respondents included more than 9000 students in grades 9 to 12 in 8 high schools in 5 school districts across the United States. The survey instrument is the 97-item Teen Sleep Habits Survey. Logistic regression models were used to calculate adjusted odds ratios and 95% confidence intervals. Because of clustering within schools and the use of repeated measures, generalized estimating equations were used to account for variance inflation. Greater sleep duration was associated with fewer reports of various mental health- and substance use-related issues and behaviors (all P values sleep reported, there was a 28% reduction in the adjusted odds of a participant reporting that he or she felt "unhappy, sad, or depressed." Later wake-up times were associated with a reduction in risk for some, but not all factors. Later start times were significantly associated with greater sleep duration. Given that later start times allow for greater sleep duration and that adequate sleep duration is associated with more favorable mental health- and substance use-related issues and behaviors, it is important that school districts prioritize exploring and implementing policies, such as delayed start times, that may increase the amount of sleep of adolescent students, which is needed for their optimal development. Copyright © 2017 National Sleep Foundation. Published by Elsevier Inc. All rights reserved.

  14. EFFECTS OF USING PHASE CHANGE MATERIALS ON THE COLD START EXHAUST EMİSSİONS CHARACTERİSTİCS OF DIESEL ENGINES

    Directory of Open Access Journals (Sweden)

    Ferhat Kaya

    2016-05-01

    Full Text Available During the last two decades, the diesel engine performance and drivability have significantly improved with the latest technologic developments. Nevertheless, one of the disadvantageous of diesel engines is related to the difficulties for starting at cold conditions, particularly in the conditions where the ambient temperature is near or below 0ºC. Additionally, the harmful exhaust emissions are also at significantly important levels during the cold start conditions. Most of carbon monoxide (CO emissions from diesel engines are produced during the engine warm-up period.  In order to improve cold start characteristics of diesel engines, many measures have been proposed, such as glow plugs and air heaters in air intake lines.In this study, in order to increase the cold start performance and improve the exhaust emission characteristics of a direct injection diesel engine, phase change materials (PCMs have been used.PCMs have high heats of fusion and they can absorb latent energy before melting. During the phase change, temperature of PCMs remains nearly constant. In this study, a PCMs was used with the 45-51ºC melting temperature band in a heat exchanger. Hot water from an external source was circulated in the exchanger to carry out the experiments in the same conditions and was used as heat source in order to melt the PCMs.Engine intake air has been passed through the exchanger before engine intake manifold.  During the engine cooling period, the PCM in the produced heat exchanger have increased the cooling time period of engine intake air.An experimental setup has been established to observe the cold start characteristics of the two cylinder diesel engine with and without using the produced exchanger. Temperature measurements from different points, CO exhaust emissions, engine speed and in cylinder pressure measurements have been used to evaluate the contribution of exchanger and increasing the intake air temperature by using the PCMs. The

  15. Impact of delaying school start time on adolescent sleep, mood, and behavior.

    Science.gov (United States)

    Owens, Judith A; Belon, Katherine; Moss, Patricia

    2010-07-01

    To examine the impact of a 30-minute delay in school start time on adolescents' sleep, mood, and behavior. Participants completed the online retrospective Sleep Habits Survey before and after a change in school start time. An independent high school in Rhode Island. Students (n = 201) in grades 9 through 12. Intervention Institution of a delay in school start time from 8 to 8:30 am. Sleep patterns and behavior, daytime sleepiness, mood, data from the Health Center, and absences/tardies. After the start time delay, mean school night sleep duration increased by 45 minutes, and average bedtime advanced by 18 minutes (95% confidence interval, 7-29 minutes [t(423) = 3.36; P students getting less than 7 hours of sleep decreased by 79.4%, and those reporting at least 8 hours of sleep increased from 16.4% to 54.7%. Students reported significantly more satisfaction with sleep and experienced improved motivation. Daytime sleepiness, fatigue, and depressed mood were all reduced. Most health-related variables, including Health Center visits for fatigue-related complaints, and class attendance also improved. A modest delay in school start time was associated with significant improvements in measures of adolescent alertness, mood, and health. The results of this study support the potential benefits of adjusting school schedules to adolescents' sleep needs, circadian rhythm, and developmental stage.

  16. Start time variability and predictability in railroad train and engine freight and passenger service employees.

    Science.gov (United States)

    2014-04-01

    Start time variability in work schedules is often hypothesized to be a cause of railroad employee fatigue because unpredictable work start times prevent employees from planning sleep and personal activities. This report examines work start time diffe...

  17. Time program using in automatization of steam turbines start-up

    International Nuclear Information System (INIS)

    Lejzerovich, A.Sh.; Melamed, A.D.

    Examples and arguments for developing time programs of changing basic parameters of automated start-up of TPP and NPP high-power steam turbines are considered. Basic parameters subject to controlled changing at automatization of turbine start-up are rotation frequency, loading and temperature of steam supplied to the turbine. Principle facility schemes of program regulation of steam temperature at the start-up are presented. The facility scheme of loading the NPP wet steam turbine is given. The principles of developing time programs, of changing basic parameters of automated start-up enable realizing transient processes close to theoretically optimum processes at arbitrary prestart-up state of the turbine by means of rather simple autatic facilities. In particular, for automated temperature increase of steam supplied to the turbine of TES power units and AES turbine loading, it is advisable to use programs in the form of linear dependence of velocity of changing the controlled parameter on the given value, the initial level, from which the parameter increase with a regulated velocity is realized, is given in the form of analogue dependence on the turbine prestart-up state. The programs described and the schemes of their realization have been approved at the automatization of 300 MW power unit starts up with the K-300-240 turbine and K-220-44 turbine as well as used when creating control system for turbines of 500 MW and higher for designed TPP and NPP power units

  18. The economic implications of later school start times in the United States.

    Science.gov (United States)

    Hafner, Marco; Stepanek, Martin; Troxel, Wendy M

    2017-12-01

    Numerous studies have shown that later school start times (SST) are associated with positive student outcomes, including improvements in academic performance, mental and physical health, and public safety. While the benefits of later SST are very well documented in the literature, in practice there is opposition against delaying SST. A major argument against later SST is the claim that delaying SST will result in significant additional costs for schools due to changes in bussing strategies. However, to date, there has only been one published study that has quantified the potential economic benefits of later SST in relation to potential costs. The current study investigates the economic implications of later school start times by examining a policy experiment and its subsequent state-wide economic effects of a state-wide universal shift in school start times to 8.30AM. Using a novel macroeconomic modeling approach, the study estimates changes in the economic performance of 47 US states following a delayed school start time, which includes the benefits of higher academic performance of students and reduced car crash rates. The benefit-cost projections of this study suggest that delaying school start times is a cost-effective, population-level strategy, which could have a significant impact on public health and the US economy. From a policy perspective, these findings are crucial as they demonstrate that significant economic gains resulting from the delay in SST accrue over a relatively short period of time following the adoption of the policy shift. Copyright © 2017 National Sleep Foundation. Published by Elsevier Inc. All rights reserved.

  19. Start-up procedure

    International Nuclear Information System (INIS)

    Marchl, A.; Krebs, W.D.; Aleite, W.

    1975-01-01

    The start-up procedure will be shown on a pressurized water reactor, although most of the activities will occur similarly in other reactor types. The commissioning time can be divided into 5 sections, the phases A to E together lasting 26 months. Subsequently there are a test run of one month and the handling-over of the plant to the operator. A survey of the commissioning sections with several important main events is shown. (orig./TK) [de

  20. A position-sensitive start detector for time-of-flight measurement

    International Nuclear Information System (INIS)

    Ikezoe, Hiroshi; Shikazono, Naomoto; Isoyama, Goro.

    1978-08-01

    A position-sensitive start detector for a time-of-flight measurement is described. In this detector microchannel plates were used to obtain time and position signals simultaneously. A time resolution of 121 psec FWHM and a position resolution of 0.28 mm FWHM were obtained for α-particles from an 241 Am source. (auth.)

  1. School start times and teenage driver motor vehicle crashes.

    Science.gov (United States)

    2015-12-01

    There is substantial evidence that lack of sleep is a significant factor in motor vehicle crashes experienced by teenage drivers. This report examines the hypothesis that a later high school start time may reduce crash rates by reducing the interfere...

  2. Detecting macroeconomic phases in the Dow Jones Industrial Average time series

    Science.gov (United States)

    Wong, Jian Cheng; Lian, Heng; Cheong, Siew Ann

    2009-11-01

    In this paper, we perform statistical segmentation and clustering analysis of the Dow Jones Industrial Average (DJI) time series between January 1997 and August 2008. Modeling the index movements and log-index movements as stationary Gaussian processes, we find a total of 116 and 119 statistically stationary segments respectively. These can then be grouped into between five and seven clusters, each representing a different macroeconomic phase. The macroeconomic phases are distinguished primarily by their volatilities. We find that the US economy, as measured by the DJI, spends most of its time in a low-volatility phase and a high-volatility phase. The former can be roughly associated with economic expansion, while the latter contains the economic contraction phase in the standard economic cycle. Both phases are interrupted by a moderate-volatility market correction phase, but extremely-high-volatility market crashes are found mostly within the high-volatility phase. From the temporal distribution of various phases, we see a high-volatility phase from mid-1998 to mid-2003, and another starting mid-2007 (the current global financial crisis). Transitions from the low-volatility phase to the high-volatility phase are preceded by a series of precursor shocks, whereas the transition from the high-volatility phase to the low-volatility phase is preceded by a series of inverted shocks. The time scale for both types of transitions is about a year. We also identify the July 1997 Asian Financial Crisis to be the trigger for the mid-1998 transition, and an unnamed May 2006 market event related to corrections in the Chinese markets to be the trigger for the mid-2007 transition.

  3. Later school start time is associated with improved sleep and daytime functioning in adolescents.

    Science.gov (United States)

    Boergers, Julie; Gable, Christopher J; Owens, Judith A

    2014-01-01

    Chronic insufficient sleep is a growing concern among adolescents and is associated with a host of adverse health consequences. Early school start times may be an environmental contributor to this problem. The purpose of this study was to examine the impact of a delay in school start time on sleep patterns, sleepiness, mood, and health-related outcomes. Boarding students (n = 197, mean age = 15.6 yr) attending an independent high school completed the School Sleep Habits Survey before and after the school start time was experimentally delayed from 8:00 a.m. to 8:25 a.m. The delay in school start time was associated with a significant (29 min) increase in sleep duration on school nights. The percentage of students receiving 8 or more hours of sleep on a school night increased to more than double, from 18% to 44%. Students in 9th and 10th grade and those with lower baseline sleep amounts were more likely to report improvements in sleep duration after the schedule change. Daytime sleepiness, depressed mood, and caffeine use were all significantly reduced after the delay in school start time. Sleep duration reverted to baseline levels when the original (earlier) school start time was reinstituted. A modest (25 min) delay in school start time was associated with significant improvements in sleep duration, daytime sleepiness, mood, and caffeine use. These findings have important implications for public policy and add to research suggesting the health benefits of modifying school schedules to more closely align with adolescents' circadian rhythms and sleep needs.

  4. School start times and teen driver crashes : traffic tech.

    Science.gov (United States)

    2015-12-01

    Sleep health has become an increasingly important and studied : topic in the last decade. So much so that a number of : school districts across the United States have explored changing, : or have already changed their high-school start times to : a l...

  5. Backstroke start kinematic and kinetic changes due to different feet positioning.

    Science.gov (United States)

    de Jesus, Karla; de Jesus, Kelly; Figueiredo, Pedro; Gonçalves, Pedro; Pereira, Suzana Matheus; Vilas-Boas, João Paulo; Fernandes, Ricardo Jorge

    2013-01-01

    The backstroke swimming start international rules changed in 2005. This study compared two backstroke start variants, both with feet parallel to each other but in complete immersion and emersion. Six elite swimmers performed two sets of 4 maximal 15 m bouts, each set using one of the variants. The starts were videotaped in the sagittal plane with two cameras, providing bi-dimensional dual-media kinematic evaluation, and an underwater force plate and a handgrip instrumented with a load cell collected kinetic data. Backstroke start with feet immerged displayed greater centre-of-mass horizontal starting position, centre-of-mass horizontal velocity at hands-off and take-off angle. Backstroke start with feet emerged showed greater wall contact time, centre-of-mass horizontal and downward vertical velocity at take-off, lower limbs horizontal impulse, and centre-of-mass downward vertical velocity during flight phase. Backstroke start with feet immerged and emerged displayed similar centre-of-mass horizontal water reach, back arc angle and 5 m starting time. Irrespective of the swimmer's feet positioning, coaches should emphasise each variant's mechanical advantages during the wall contact phases. Furthermore, the maintenance of those advantages throughout the flight should be stressed for better backstroke start performance.

  6. Skeleton sled velocity profiles: a novel approach to understand critical aspects of the elite athletes' start phases.

    Science.gov (United States)

    Colyer, Steffi L; Stokes, Keith A; Bilzon, James L J; Salo, Aki I T

    2018-06-01

    The development of velocity across the skeleton start is critical to performance, yet poorly understood. We aimed to understand which components of the sled velocity profile determine performance and how physical abilities influence these components. Thirteen well-trained skeleton athletes (>85% of athletes in the country) performed dry-land push-starts alongside countermovement jump and sprint tests at multiple time-points. A magnet encoder attached to the sled wheel provided velocity profiles, which were characterised using novel performance descriptors. Stepwise regression revealed four variables (pre-load velocity, pre-load distance, load effectiveness, velocity drop) to explain 99% variance in performance (β weights: 1.70, -0.81, 0.25, -0.07, respectively). Sprint times and jump ability were associated (r ± 90% CI) with pre-load velocity (-0.70 ± 0.27 and 0.88 ± 0.14, respectively) and distance (-0.48 ± 0.39 and 0.67 ± 0.29, respectively), however, unclear relationships between both physical measures and load effectiveness (0.33 ± 0.44 and -0.35 ± 0.48, respectively) were observed. Athletes should develop accelerative ability to attain higher velocity earlier on the track. Additionally, the loading phase should not be overlooked and may be more influenced by technique than physical factors. Future studies should utilise this novel approach when evaluating skeleton starts or interventions to enhance performance.

  7. School Start Times, Sleep, Behavioral, Health, and Academic Outcomes: a Review of the Literature

    Science.gov (United States)

    Chapman, Daniel P.; Croft, Janet B.

    2015-01-01

    BACKGROUND Insufficient sleep in adolescents has been shown to be associated with a wide variety of adverse outcomes, from poor mental and physical health to behavioral problems and lower academic grades. However, most high school students do not get sufficient sleep. Delaying school start times for adolescents has been proposed as a policy change to address insufficient sleep in this population and potentially to improve students’ academic performance, reduce engagement in risk behaviors, and improve health. METHODS This paper reviews 38 reports examining the association between school start times, sleep, and other outcomes among adolescent students. RESULTS Most studies reviewed provide evidence that delaying school start time increases weeknight sleep duration among adolescents, primarily by delaying rise times. Most of the studies saw a significant increase in sleep duration even with relatively small delays in start times of half an hour or so. Later start times also generally correspond to improved attendance, less tardiness, less falling asleep in class, better grades, and fewer motor vehicle crashes. CONCLUSIONS Although additional research is necessary, research results that are already available should be disseminated to stakeholders to enable the development of evidence-based school policies. PMID:27040474

  8. Time-invariant PT product and phase locking in PT -symmetric lattice models

    Science.gov (United States)

    Joglekar, Yogesh N.; Onanga, Franck Assogba; Harter, Andrew K.

    2018-01-01

    Over the past decade, non-Hermitian, PT -symmetric Hamiltonians have been investigated as candidates for both a fundamental, unitary, quantum theory and open systems with a nonunitary time evolution. In this paper, we investigate the implications of the former approach in the context of the latter. Motivated by the invariance of the PT (inner) product under time evolution, we discuss the dynamics of wave-function phases in a wide range of PT -symmetric lattice models. In particular, we numerically show that, starting with a random initial state, a universal, gain-site location dependent locking between wave-function phases at adjacent sites occurs in the PT -symmetry-broken region. Our results pave the way towards understanding the physically observable implications of time invariants in the nonunitary dynamics produced by PT -symmetric Hamiltonians.

  9. Standardization of the time for the execution of HANARO start-up and shutdown procedures

    International Nuclear Information System (INIS)

    Choi, H. Y.; Lim, I. C.; Hwang, S. R.; Kang, T. J.; Youn, D. B.

    2003-01-01

    For the standardization of the time to execute HANARO start-up and shutdown procedures, code names were assigned to the individual procedures and the work time were investigated. The data recorded by the operators during start-up and shutdown were statistically analyzed. The analysis results will be used for the standardization of start-up and shutdown procedures and it will be reflected in the procedure document

  10. High school start times after 8:30 am are associated with later wake times and longer time in bed among teens in a national urban cohort study.

    Science.gov (United States)

    Nahmod, Nicole G; Lee, Soomi; Buxton, Orfeu M; Chang, Anne-Marie; Hale, Lauren

    2017-12-01

    High school start times are a key contributor to insufficient sleep. This study investigated associations of high school start times with bedtime, wake time, and time in bed among urban teenagers. Daily-diary study nested within the prospective Fragile Families and Child Wellbeing Study. Twenty US cities. Four hundred thirteen teenagers who completed ≥1 daily diary report on a school day. Participating teens were asked to complete daily diaries for 7 consecutive days. School-day daily diaries (3.8±1.6 entries per person) were used in analyses (N=1555 school days). High school start time, the main predictor, was categorized as 7:00-7:29 am (15%), 7:30-7:59 am (22%), 8:00-8:29 am (35%), and 8:30 am or later (28%). Multilevel modeling examined the associations of school start times with bedtime, wake time, and time in bed. Models adjusted for age, sex, race/ethnicity, household income, caregiver's education, and school type. Teens with the earliest high school start times (7:00-7:29 am) obtained 46 minutes less time in bed on average compared with teens with high school start times at 8:30 am or later (Pstart times and shorter time in bed, primarily due to earlier wake times (PStart times after 8:30 am were associated with increased time in bed, extending morning sleep by 27-57 minutes (Pstart times. Later school start times are associated with later wake times in our large, diverse sample. Teens starting school at 8:30 am or later are the only group with an average time in bed permitting 8 hours of sleep, the minimum recommended by expert consensus for health and well-being. Copyright © 2017 National Sleep Foundation. Published by Elsevier Inc. All rights reserved.

  11. IMMEDIATE EFFECTS OF DEEP TRUNK MUSCLE TRAINING ON SWIMMING START PERFORMANCE.

    Science.gov (United States)

    Iizuka, Satoshi; Imai, Atsushi; Koizumi, Keisuke; Okuno, Keisuke; Kaneoka, Koji

    2016-12-01

    In recent years, deep trunk muscle training has been adopted in various sports, including swimming. This is performed both in everyday training and as part of the warm-up routine before competitive races. It is suggested that trunk stabilization exercises are effective in preventing injury, and aid in improving performance. However, conclusive evidence of the same is yet to be obtained. The time of start phase of swimming is a factor that can significantly influence competition performance in a swimming race. If trunk stabilization exercises can provide instantaneous trunk stability, it is expected that they will lead to performance improvements in the start phase of swimming. The purpose of this study was to investigate the immediate effect of trunk stabilization exercises on the start phase in swimming. Intervention study. Nine elite male swimmers (mean age 20.2 ± 1.0 years; height 174.4 ± 3.5 cm; weight 68.9 ± 4.1 kg) performed the swimming start movement. The measurement variables studied included flying distance, and the time and velocity of subjects at hands' entry and on reaching five meters. Measurements were taken in trials immediately before and after the trunk stabilization exercises. A comparison between pre- and post-exercise measurements was assessed. The time to reach five meters (T 5m ) decreased significantly after trunk stabilization exercises, by 0.019 s (p = 0.02). Velocity at entry (V entry ) did not demonstrate significant change, while velocity at five meters (V 5m ) increased significantly after the exercises (p = 0.023). In addition, the speed reduction rate calculated from V entry and V 5m significantly decreased by 5.17% after the intervention (p = 0.036). Trunk stabilization exercises may help reduce the time from start to five meters in the start phase in swimming. The results support the hypothesis that these exercises may improve swimming performance. Level 3b.

  12. Risk Reduction Effects Due to the Start Time Extension of EDGs in OPR-1000

    International Nuclear Information System (INIS)

    Lim, Ho-Gon; Yang, Joon-Eon; Hwang, Mee-Jeong

    2006-01-01

    Under the condition that the ECCS rule in Korea will be revised based on the new U.S. 10 CFR 50.46, the risk impact due to the EDG start time extension is analyzed in the present study. This paper is composed of 6 sections. In the section 2, the LOCA break size that cannot be mitigable under the condition of extended EDG start time is obtained from the thermal hydraulic analysis. The section 3 discusses the frequency of the immitigable LOCA and the probability of the LOOP given a LOCA. In the section 4, the effect of the EDG start time extension on its failure probability is discussed with a qualitative manner. Finally, the whole risk change due to the EDG start time extension is calculated in the section 5 with the conclusions given in the section 6

  13. School Start Times, Sleep, Behavioral, Health, and Academic Outcomes: A Review of the Literature.

    Science.gov (United States)

    Wheaton, Anne G; Chapman, Daniel P; Croft, Janet B

    2016-05-01

    Insufficient sleep in adolescents has been shown to be associated with a wide variety of adverse outcomes, from poor mental and physical health to behavioral problems and lower academic grades. However, most high school students do not get sufficient sleep. Delaying school start times for adolescents has been proposed as a policy change to address insufficient sleep in this population and potentially to improve students' academic performance, reduce engagement in risk behaviors, and improve health. This article reviews 38 reports examining the association between school start times, sleep, and other outcomes among adolescent students. Most studies reviewed provide evidence that delaying school start time increases weeknight sleep duration among adolescents, primarily by delaying rise times. Most of the studies saw a significant increase in sleep duration even with relatively small delays in start times of half an hour or so. Later start times also generally correspond to improved attendance, less tardiness, less falling asleep in class, better grades, and fewer motor vehicle crashes. Although additional research is necessary, research results that are already available should be disseminated to stakeholders to enable the development of evidence-based school policies. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

  14. Middle school start times: the importance of a good night's sleep for young adolescents.

    Science.gov (United States)

    Wolfson, Amy R; Spaulding, Noah L; Dandrow, Craig; Baroni, Elizabeth M

    2007-01-01

    With the onset of adolescence, teenagers require 9.2 hr of sleep and experience a delay in the timing of sleep. In the "real world" with early school start times, however, they report less sleep, striking differences between their school-weekend sleep schedules, and significant daytime sleepiness. Prior studies demonstrated that high schoolers with later school starts do not further delay bedtime but obtain more sleep due to later wake times. This study examined sleep-wake patterns of young adolescents attending urban, public middle schools with early (7:15 a.m.) versus late (8:37 a.m.) start times. Students (N = 205) were assessed at 2 time periods. Students at the late-starting school reported waking up over 1 hr later on school mornings and obtaining 50 min more sleep each night, less sleepiness, and fewer tardies than students at the early school. All students reported similar school-night bedtime, sleep hygiene practices, and weekend sleep schedules.

  15. Considerations in the rationale, design and methods of the Strategic Timing of AntiRetroviral Treatment (START) study

    Science.gov (United States)

    Babiker, Abdel G; Emery, Sean; Fätkenheuer, Gerd; Gordin, Fred M; Grund, Birgit; Lundgren, Jens D; Neaton, James D; Pett, Sarah L; Phillips, Andrew; Touloumi, Giota; Vjecha, Michael J

    2012-01-01

    Background Untreated human immunodeficiency virus (HIV) infection is characterized by progressive depletion of CD4+ T lymphocyte (CD4) count leading to the development of opportunistic diseases (acquired immunodeficiency syndrome (AIDS)), and more recent data suggest that HIV is also associated with an increased risk of serious non-AIDS (SNA) diseases including cardiovascular, renal, and liver diseases and non-AIDS-defining cancers. Although combination antiretroviral treatment (ART) has resulted in a substantial decrease in morbidity and mortality in persons with HIV infection, viral eradication is not feasible with currently available drugs. The optimal time to start ART for asymptomatic HIV infection is controversial and remains one of the key unanswered questions in the clinical management of HIV-infected individuals. Purpose In this article, we outline the rationale and methods of the Strategic Timing of AntiRetroviral Treatment (START) study, an ongoing multicenter international trial designed to assess the risks and benefits of initiating ART earlier than is currently practiced. We also describe some of the challenges encountered in the design and implementation of the study and how these challenges were addressed. Methods A total of 4000 study participants who are HIV type 1 (HIV-1) infected, ART naïve with CD4 count > 500 cells/μL are to be randomly allocated in a 1:1 ratio to start ART immediately (early ART) or defer treatment until CD4 count is AIDS, SNA, or death. The study had a pilot phase to establish feasibility of accrual, which was set as the enrollment of at least 900 participants in the first year. Results Challenges encountered in the design and implementation of the study included the limited amount of data on the risk of a major component of the primary endpoint (SNA) in the study population, changes in treatment guidelines when the pilot phase was well underway, and the complexities of conducting the trial in a geographically wide

  16. A quasi-experimental study of the impact of school start time changes on adolescent sleep.

    Science.gov (United States)

    Owens, Judith A; Dearth-Wesley, Tracy; Herman, Allison N; Oakes, J Michael; Whitaker, Robert C

    2017-12-01

    To determine whether simultaneous school start time changes (delay for some schools; advance for others) impact adolescents' sleep. Quasi-experimental study using cross-sectional surveys before and after changes to school start times in September 2015. Eight middle (grades 7-8), 3 secondary (grades 7-12), and 8 high (grades 9-12) schools in Fairfax County (Virginia) public schools. A total of 2017 (6% of ~34,900) students were surveyed before start time changes, and 1180 (3% of ~35,300) were surveyed after. A 50-minute delay (7:20 to 8:10 am) in start time for high schools and secondary schools and a 30-minute advance (8:00 to 7:30 am) for middle schools. Differences before and after start time changes in self-reported sleep duration and daytime sleepiness. Among respondents, 57.5% were non-Hispanic white, and 10.3% received free or reduced-priced school meals. Before start time changes, high/secondary and middle school students slept a mean (SD) of 7.4 (1.2) and 8.4 (1.0) hours on school nights, respectively, and had a prevalence of daytime sleepiness of 78.4% and 57.2%, respectively. Adjusted for potential confounders, students with a 50-minute delay slept 30.1 minutes longer (95% confidence interval [CI], 24.3-36.0) on school nights and had less daytime sleepiness (-4.8%; 95% CI, -8.5% to -1.1%), whereas students with a 30-minute advance slept 14.8 minutes less (95% CI, -21.6 to -8.0) and had more daytime sleepiness (8.0%; 95% CI, 2.5%-13.5%). Both advances and delays in school start times are associated with changes in adolescents' school-night sleep duration and daytime sleepiness. Larger changes might occur with later start times. Copyright © 2017 National Sleep Foundation. Published by Elsevier Inc. All rights reserved.

  17. Delayed High School Starting Times. Information Capsule. Volume 0908

    Science.gov (United States)

    Blazer, Christie

    2009-01-01

    Educators around the nation are considering pushing high school starting times back until later in the morning, based on evidence suggesting that amount of sleep and circadian rhythms play a part in adolescents' academic performance. While research confirms that adolescents do not get enough sleep and that insufficient sleep can negatively…

  18. Longitudinal Outcomes of Start Time Delay on Sleep, Behavior, and Achievement in High School

    Science.gov (United States)

    Thacher, Pamela V.; Onyper, Serge V.

    2016-01-01

    Study Objectives: To establish whether sleep, health, mood, behavior, and academics improved after a 45-minute delay in high school start time, and whether changes persisted longitudinally. Methods: We collected data from school records and student self-report across a number of domains at baseline (May 2012) and at two follow-up time points (November 2012 and May 2013), at a public high school in upstate New York. Students enrolled during academic years (AY) 2011–2012 and 2012–2013 completed the Pittsburgh Sleep Quality Index; the DASS-21; the “Owl-Lark” Scale; the Daytime Sleepiness Index; and a brief self-report of health. Reports from school records regarding attendance, tardiness, disciplinary violations, and academic performance were collected for AY 2010–2011 through 2013–2014. Results: Students delayed but did not extend their sleep period; we found lasting improvements in tardiness and disciplinary violations after the start-time delay, but no changes to other variables. At the first follow-up, students reported 20 minutes longer sleep, driven by later rise times and stable bed times. At the second follow-up, students maintained later rise times but delayed bedtimes, returning total sleep to baseline levels. A delay in rise time, paralleling the delay in the start time that occurred, resulted in less tardiness and decreased disciplinary incidents, but larger improvements to sleep patterns may be necessary to affect health, attendance, sleepiness, and academic performance. Conclusions: Later start times improved tardiness and disciplinary issues at this school district. A delay in start time may be a necessary but not sufficient means to increase sleep time and may depend on preexisting individual differences. Commentary: A commentary on this article appears in this issue on page 267. Citation: Thacher PV, Onyper SV. Longitudinal outcomes of start time delay on sleep, behavior, and achievement in high school. SLEEP 2016;39(2):271–281. PMID

  19. Class start times, sleep, and academic performance in college: a path analysis.

    Science.gov (United States)

    Onyper, Serge V; Thacher, Pamela V; Gilbert, Jack W; Gradess, Samuel G

    2012-04-01

    Path analysis was used to examine the relationship between class start times, sleep, circadian preference, and academic performance in college-aged adults. Consistent with observations in middle and high school students, college students with later class start times slept longer, experienced less daytime sleepiness, and were less likely to miss class. Chronotype was an important moderator of sleep schedules and daytime functioning; those with morning preference went to bed and woke up earlier and functioned better throughout the day. The benefits of taking later classes did not extend to academic performance, however; grades were somewhat lower in students with predominantly late class schedules. Furthermore, students taking later classes were at greater risk for increased alcohol consumption, and among all the factors affecting academic performance, alcohol misuse exerted the strongest effect. Thus, these results indicate that later class start times in college, while allowing for more sleep, also increase the likelihood of alcohol misuse, ultimately impeding academic success.

  20. MR angiography of the pelvic and lower leg arteries: starting with time-resolved imaging of the lower leg is recommended

    International Nuclear Information System (INIS)

    Schmitt, R.; Christopoulos, G.; Brunner, S.; Froehner, S.; Dobritz, M.; Fellner, F.

    2001-01-01

    58 patients suffering from peripheral arterial vascular disease were examined using contrast-enhanced MR angiography with the intention of optimizing the visualization of lower leg arteries. Different from the customary acquisition order, were first the arteries of the lower legs depicted with three time-resolved phases. Afterwards, the iliacal and femoral vessels were imaged by applying the floating-table technique in two steps. In all cases, the lower leg arteries were depicted without overlying veins. By injecting the contrast agent in two phases, imaging quality of the iliofemoral arteries was not significantly reduced. - In conclusion, we would recommend the hybrid technique of peripheral contrast-enhanced MRA with primarily starting the acquisition of the lower legs in cases of foot infections or ulcerations where the transit time is reduced bi- or unilaterally. (orig.) [de

  1. Delayed school start times and adolescent sleep: A systematic review of the experimental evidence.

    Science.gov (United States)

    Minges, Karl E; Redeker, Nancy S

    2016-08-01

    Many schools have instituted later morning start times to improve sleep, academic, and other outcomes in response to the mismatch between youth circadian rhythms and early morning start times. However, there has been no systematic synthesis of the evidence on the effects of this practice. To examine the impact of delayed school start time on students' sleep, health, and academic outcomes, electronic databases were systematically searched and data were extracted using the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. Six studies satisfied selection criteria and used pre-post, no control (n = 3), randomized controlled trial (n = 2), and quasi-experimental (n = 1) designs. School start times were delayed 25-60 min, and correspondingly, total sleep time increased from 25 to 77 min per weeknight. Some studies revealed reduced daytime sleepiness, depression, caffeine use, tardiness to class, and trouble staying awake. Overall, the evidence supports recent non-experimental study findings and calls for policy that advocates for delayed school start time to improve sleep. This presents a potential long-term solution to chronic sleep restriction during adolescence. However, there is a need for rigorous randomized study designs and reporting of consistent outcomes, including objective sleep measures and consistent measures of health and academic performance. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. A Compact Safe Cold-Start (CS2) System for Scramjets using Dilute Triethylaluminum Fuel Mixtures, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal leverages a highly successful Phase 1 feasibility effort to further develop a system that satisfies the cold-start requirements of scramjet engines....

  3. Earlier school start times are associated with higher rates of behavioral problems in elementary schools.

    Science.gov (United States)

    Keller, Peggy S; Gilbert, Lauren R; Haak, Eric A; Bi, Shuang; Smith, Olivia A

    2017-04-01

    Early school start times may curtail children's sleep and inadvertently promote sleep restriction. The current study examines the potential implications for early school start times for behavioral problems in public elementary schools (student ages 5-12 years) in Kentucky. School start times were obtained from school Web sites or by calling school offices; behavioral and disciplinary problems, along with demographic information about schools, were obtained from the Kentucky Department of Education. Estimated associations controlled for teacher/student ratio, racial composition, school rank, enrollment, and Appalachian location. Associations between early school start time and greater behavioral problems (harassment, in-school removals, suspensions, and expulsions) were observed, although some of these associations were found only for schools serving the non-Appalachian region. Findings support the growing body of research showing that early school start times may contribute to student problems, and extend this research through a large-scale examination of elementary schools, behavioral outcomes, and potential moderators of risk. Copyright © 2017 National Sleep Foundation. Published by Elsevier Inc. All rights reserved.

  4. Longitudinal Outcomes of Start Time Delay on Sleep, Behavior, and Achievement in High School.

    Science.gov (United States)

    Thacher, Pamela V; Onyper, Serge V

    2016-02-01

    To establish whether sleep, health, mood, behavior, and academics improved after a 45-minute delay in high school start time, and whether changes persisted longitudinally. We collected data from school records and student self-report across a number of domains at baseline (May 2012) and at two follow-up time points (November 2012 and May 2013), at a public high school in upstate New York. Students enrolled during academic years (AY) 2011-2012 and 2012-2013 completed the Pittsburgh Sleep Quality Index; the DASS-21; the "Owl-Lark" Scale; the Daytime Sleepiness Index; and a brief self-report of health. Reports from school records regarding attendance, tardiness, disciplinary violations, and academic performance were collected for AY 2010-2011 through 2013-2014. Students delayed but did not extend their sleep period; we found lasting improvements in tardiness and disciplinary violations after the start-time delay, but no changes to other variables. At the first follow-up, students reported 20 minutes longer sleep, driven by later rise times and stable bed times. At the second follow-up, students maintained later rise times but delayed bedtimes, returning total sleep to baseline levels. A delay in rise time, paralleling the delay in the start time that occurred, resulted in less tardiness and decreased disciplinary incidents, but larger improvements to sleep patterns may be necessary to affect health, attendance, sleepiness, and academic performance. Later start times improved tardiness and disciplinary issues at this school district. A delay in start time may be a necessary but not sufficient means to increase sleep time and may depend on preexisting individual differences. A commentary on this article appears in this issue on page 267. © 2016 Associated Professional Sleep Societies, LLC.

  5. Starting manufacturing phase of ITER upper ports

    Energy Technology Data Exchange (ETDEWEB)

    Utin, Yuri, E-mail: yuri.utin@iter.org [ITER Organization, Route de Vinon-sur-Verdon, CS 90 046, 13067 St. Paul Lez Durance Cedex (France); Alekseev, Alexander; Sborchia, Carlo; Choi, Changho; Albin, Vincent; Barabash, Vladimir; Davis, James [ITER Organization, Route de Vinon-sur-Verdon, CS 90 046, 13067 St. Paul Lez Durance Cedex (France); Fabritsiev, Sergey [NTC Sintez, Efremov Inst., 189631 Metallostroy, St. Petersburg (Russian Federation); Giraud, Benoit; Guirao, Julio [ITER Organization, Route de Vinon-sur-Verdon, CS 90 046, 13067 St. Paul Lez Durance Cedex (France); Koenig, Werner [MAN Diesel & Turbo SE, Werftstrasse 17, Deggendorf (Germany); Kedrov, Igor; Kuzmin, Evgeny [NTC Sintez, Efremov Inst., 189631 Metallostroy, St. Petersburg (Russian Federation); Levesy, Bruno; Martinez, Jean-Marc [ITER Organization, Route de Vinon-sur-Verdon, CS 90 046, 13067 St. Paul Lez Durance Cedex (France); Prebeck, Markus [MAN Diesel & Turbo SE, Werftstrasse 17, Deggendorf (Germany); Privalova, Elena [NTC Sintez, Efremov Inst., 189631 Metallostroy, St. Petersburg (Russian Federation); Ranzinger, Franz [MAN Diesel & Turbo SE, Werftstrasse 17, Deggendorf (Germany); Savrukhin, Petr [Russian Federation ITER Domestic Agency, Kurchatov sq.1, 123182 Moscow (Russian Federation); Schiller, Thomas [MAN Diesel & Turbo SE, Werftstrasse 17, Deggendorf (Germany); and others

    2015-10-15

    Highlights: • The port plugs are attached to the ports with high-strength fasteners. • Tightening of the fasteners via inductive heating was tested. • A concept for the port/plug sealing with metal-type gaskets has progressed. • Manufacturing design of the Upper Ports is in progress. • A full-scale mock-up of double-wall part of the port stub extension is in manufacturing process – acceptable final tolerances are expected. - Abstract: The ITER Vacuum Vessel (VV) features upper, equatorial and lower ports. The upper and regular equatorial ports are occupied by the port plugs. Although the port design has been overall completed in the past, the design of some remaining interfaces was still in progress: in particular, the Sealing Flange package, which includes the high-vacuum seals and the plug fasteners. As the ITER construction phase has started, the procurement of the VV ports has been launched. The VV upper ports will be procured by the Russian Federation Domestic Agency. The main suppliers were selected and the manufacturing design of the first parts is in full progress now. Since the VV is classified at nuclear level N2, the design and manufacture of its components are to be compliant with the French RCC-MR code and regulations for nuclear pressure equipment in France. These regulations make a strong impact to the port design and manufacturing process.

  6. Starting manufacturing phase of ITER upper ports

    International Nuclear Information System (INIS)

    Utin, Yuri; Alekseev, Alexander; Sborchia, Carlo; Choi, Changho; Albin, Vincent; Barabash, Vladimir; Davis, James; Fabritsiev, Sergey; Giraud, Benoit; Guirao, Julio; Koenig, Werner; Kedrov, Igor; Kuzmin, Evgeny; Levesy, Bruno; Martinez, Jean-Marc; Prebeck, Markus; Privalova, Elena; Ranzinger, Franz; Savrukhin, Petr; Schiller, Thomas

    2015-01-01

    Highlights: • The port plugs are attached to the ports with high-strength fasteners. • Tightening of the fasteners via inductive heating was tested. • A concept for the port/plug sealing with metal-type gaskets has progressed. • Manufacturing design of the Upper Ports is in progress. • A full-scale mock-up of double-wall part of the port stub extension is in manufacturing process – acceptable final tolerances are expected. - Abstract: The ITER Vacuum Vessel (VV) features upper, equatorial and lower ports. The upper and regular equatorial ports are occupied by the port plugs. Although the port design has been overall completed in the past, the design of some remaining interfaces was still in progress: in particular, the Sealing Flange package, which includes the high-vacuum seals and the plug fasteners. As the ITER construction phase has started, the procurement of the VV ports has been launched. The VV upper ports will be procured by the Russian Federation Domestic Agency. The main suppliers were selected and the manufacturing design of the first parts is in full progress now. Since the VV is classified at nuclear level N2, the design and manufacture of its components are to be compliant with the French RCC-MR code and regulations for nuclear pressure equipment in France. These regulations make a strong impact to the port design and manufacturing process.

  7. Start-up phase assessment of a UASB-Septic tank system treating domestic septage

    International Nuclear Information System (INIS)

    Ali, M.; Al-Saed, R.; Mahmoud, N.

    2007-01-01

    About 65% of the annual domestic waste water in Palestine is currently collected in cesspits, where inadequate disposal might cause cumulative public health risks and annual environmental degradation. This research presents the preliminary results for the start-up period of a pilot-scale UASB-septic tank system treating domestic septage of Birzet town. Under different operational conditions, the performance of the pretreatment system for the removal of organic matter and nutrients was evaluated. Initial results showed that organic pollutants removal was mainly due to biophysical processes including sedimentation and microbial degradation. During start-up phase, the system attained removal efficiency for COD total of about 80% compared to removal for COD col, and COD dis of 71% and 43% respectively. Similarly, the continuous operation mode demonstrated that the system was quite effective in removing organic pollutants. Operational experience from the initial results revealed that seeding the USAB reactor with activated sludge during the start up period was not practical. Finally, the advantage of USAB-septic tank application appeared to be achievable if adequate system operation and control over a long monitoring period were maintained. (author)

  8. Relationship between different push-off variables and start performance in experienced swimmers.

    Science.gov (United States)

    García-Ramos, Amador; Feriche, Belén; de la Fuente, Blanca; Argüelles-Cienfuegos, Javier; Strojnik, Vojko; Strumbelj, Boro; Štirn, Igor

    2015-01-01

    The objective of this study was to determine the relationship between different variables measured with a force plate during the swimming start push-off phase and start performance presented by times to 5, 10 and 15 m. Twenty-one women from the Slovenian national swimming team performed two different swim starts (freestyle and undulatory) on a portable force plate to a distance further than 15 m. Correlations between push-off variables and times to 5, 10 and 15 m were quantified through Pearson's product-moment correlation coefficient (r). The variables that significantly correlated (p  .05). Based on the results of this study, we can conclude that horizontal take-off velocity and average horizontal acceleration (calculated as the average horizontal force divided by swimmer's body mass) are the variables most related to swimming start performance in experienced swimmers, and therefore could be the preferred measures to monitor swimmers' efficiency during the push-off phase.

  9. Timing of start of dialysis in diabetes mellitus patients: a systematic literature review.

    Science.gov (United States)

    Nacak, Hakan; Bolignano, Davide; Van Diepen, Merel; Dekker, Friedo; Van Biesen, Wim

    2016-02-01

    Diabetes mellitus is a frequent cause of the need for renal replacement therapy (RRT). Historically, RRT was started earlier in patients with diabetes, in an attempt to prevent complications of uraemia and diabetes. We did a systematic review to find support for this earlier start of dialysis in patients with versus without diabetes. The MEDLINE, EMBASE and CENTRAL databases were searched for articles about the timing of dialysis initiation in (subgroups of) patients with diabetes and CKD Stage 5. A total of 340 papers were screened and 11 papers were selected to be reviewed. Only three studies showed data of at least one subgroup of patients with diabetes. Two observational studies concluded that start of dialysis with a higher estimated glomerular filtration rate (eGFR) is beneficial with regard to survival, one did not find a difference and six observational studies concluded that start of dialysis with a lower eGFR is associated with better survival in patients with diabetes. The effect of timing of initiation of dialysis did not differ between patients with versus without diabetes. Lastly, one randomized controlled trial (two papers) reported that there was no difference in survival between start at higher versus lower eGFR overall and a P-value for the interaction with diabetes of P = 0.63, indicating no difference between patients with versus without diabetes with regard to the timing of start of dialysis and subsequent mortality on dialysis. There is no difference between early (eGFR) and late (lower eGFR) start of RRT with regard to mortality in patients with versus without diabetes. RRT should thus be initiated based on the same criteria in all patients, irrespective of the presence or absence of diabetes. © The Author 2016. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.

  10. THE EFFECTS OF THREE DIFFERENT REAR KNEE ANGLES ON KINEMATICS IN THE SPRINT START

    Directory of Open Access Journals (Sweden)

    C. Milanese

    2014-08-01

    Full Text Available The purpose of this study was to investigate the rear knee angle range in the set position that allows sprinters to reach greater propulsion on the rear block during the sprint start. Eleven university-track team sprinters performed the sprint start using three rear knee angle conditions: 90°, 115° and 135°. A motion capture system consisting of 8 digital cameras (250 Hz was used to record kinematic parameters at the starting block phase and the acceleration phase. The following variables were considered: horizontal velocity of the centre of mass (COM, COM height, block time, pushing time on the rear block, percentage of pushing time on the rear block, force impulse, push-off angle and length of the first two strides. The main results show that first, horizontal block velocity is significantly greater at 90° vs 115° and 135° rear knee angle (p<0.05 and p<0.001 respectively at block clearance and the first two strides; second, during the pushing phase, the percentage of pushing time of the rear leg is significantly greater at 90° vs 135° rear knee angle (p<0.01. No significant difference was found for block time among the conditions. These results indicate that block velocity is the main kinematic parameter affected by rear knee angle during the starting block phase and acceleration phase. Furthermore, the 90° rear knee angle allows for a better push-off of the rear leg than larger angles at the set position. The findings of this study provide some direction and useful practical advice in defining an efficient rear leg biomechanical configuration at the set position.

  11. The Perfect Pairing: The Adult Learner and the Boutique Winery in the Start-Up Phase

    Science.gov (United States)

    Heath-Simpson, Delta F.

    2011-01-01

    The purpose of this phenomenological study was to understand and describe the lived experiences of adult learners who are owners and managers of small winery businesses operating in the start-up phase of the organizational life cycle. The study explored and identified the meaning of adult learning in the entrepreneurial context and its affect on…

  12. Improving on-time surgical starts: the impact of implementing pre-OR timeouts and performance pay.

    Science.gov (United States)

    Martin, Luke; Langell, John

    2017-11-01

    Operating room (OR) time is expensive. Underutilized OR time negatively impacts efficiency and is an unnecessary cost for hospitals. The purpose of this study was to evaluate the impact of a pre-OR timeout and performance pay incentive on the frequency of on-time, first surgical starts. At a single Veterans Affairs Medical Center, we implemented a pre-OR timeout in the form of a safety-briefing checklist and a modest performance pay incentive for on-time starts (>90% compliance) for attending surgeons. Data were collected on all first-start cases beginning before implementation in 2008 and continued through 2015. Each year, an average of 960 first starts occurred across nine surgical divisions. Before implementation of either the timeout or pay incentive, only 15% of cases started on time, and by 2015, greater than 72% were on time (P 60 min were not significant (P = 0.31; P = 0.81). Assuming a loss of 7 min per case for delays pay for on-time starts significantly improves OR utilization and reduces unnecessary costs. Published by Elsevier Inc.

  13. Later school start times for supporting the education, health, and well-being of high school students.

    Science.gov (United States)

    Marx, Robert; Tanner-Smith, Emily E; Davison, Colleen M; Ufholz, Lee-Anne; Freeman, John; Shankar, Ravi; Newton, Lisa; Brown, Robert S; Parpia, Alyssa S; Cozma, Ioana; Hendrikx, Shawn

    2017-07-03

    A number of school systems worldwide have proposed and implemented later school start times as a means of avoiding the potentially negative impacts that early morning schedules can have on adolescent students. Even mild sleep deprivation has been associated with significant health and educational concerns: increased risk for accidents and injuries, impaired learning, aggression, memory loss, poor self-esteem, and changes in metabolism. Although researchers have begun to explore the effects of delayed school start time, no one has conducted a rigorous review of evidence to determine whether later school start times support adolescent health, education, and well-being. We aimed to assess the effects of a later school start time for supporting health, education, and well-being in high school students.Secondary objectives were to explore possible differential effects of later school start times in student subgroups and in different types of schools; to identify implementation practices, contextual factors, and delivery modes associated with positive and negative effects of later start times; and to assess the effects of later school start times on the broader community (high school faculty and staff, neighborhood, and families). We conducted the main search for this review on 28 October 2014 and updated it on 8 February 2016. We searched CENTRAL as well as 17 key electronic databases (including MEDLINE, Embase, ERIC, PsycINFO, and Sociological Abstracts), current editions of relevant journals and organizational websites, trial registries, and Google Scholar. We included any randomized controlled trials, controlled before-and-after studies, and interrupted time series studies with sufficient data points that pertained to students aged 13 to 19 years and that compared different school start times. Studies that reported either primary outcomes of interest (academic outcomes, amount or quality of sleep, mental health indicators, attendance, or alertness) or secondary

  14. Plasma-wall Interaction Studies in the Start-up Phase of TJ-II

    International Nuclear Information System (INIS)

    De la Cal, E.; Tabares, F.L.; Tafalla, D.

    1998-01-01

    The aim of this work is to present some first plasma-wall interaction studies made during the first experimental campaign of TJ-II. The different sections contain independent contributions presented orally in the fusion division of the Euratom-Ciemat association during 1998: I. Density limit during the start-up phase of TJ-II : are we limited by radiation?. II. Temporal evolution of oxygen in the plasma during an experimental day. III. The contribution of helium to the plasma electron density IV. First studies of the S.O.L. diffusion coefficient and its dependence with the boundary plasma parameters. (Author) 3 refs

  15. Short locking time and low jitter phase-locked loop based on slope charge pump control

    International Nuclear Information System (INIS)

    Guo Zhongjie; Liu Youbao; Wu Longsheng; Wang Xihu; Tang Wei

    2010-01-01

    A novel structure of a phase-locked loop (PLL) characterized by a short locking time and low jitter is presented, which is realized by generating a linear slope charge pump current dependent on monitoring the output of the phase frequency detector (PFD) to implement adaptive bandwidth control. This improved PLL is created by utilizing a fast start-up circuit and a slope current control on a conventional charge pump PLL. First, the fast start-up circuit is enabled to achieve fast pre-charging to the loop filter. Then, when the output pulse of the PFD is larger than a minimum value, the charge pump current is increased linearly by the slope current control to ensure a shorter locking time and a lower jitter. Additionally, temperature variation is attenuated with the temperature compensation in the charge pump current design. The proposed PLL has been fabricated in a kind of DSP chip based on a 0.35 μm CMOS process. Comparing the characteristics with the classical PLL, the proposed PLL shows that it can reduce the locking time by 60% with a low peak-to-peak jitter of 0.3% at a wide operation temperature range. (semiconductor integrated circuits)

  16. The Association between Elementary School Start Time and Students' Academic Achievement in Wayzata Public Schools

    Science.gov (United States)

    Dupuis, Danielle N.

    2015-01-01

    The Center for Applied Research and Educational Improvement (CAREI) conducted two analyses with the purpose of examining the association between elementary school start time and students' academic achievement in mathematics and reading in Wayzata Public Schools. The first analysis examined the association between elementary school start time and…

  17. Lean principles optimize on-time vascular surgery operating room starts and decrease resident work hours.

    Science.gov (United States)

    Warner, Courtney J; Walsh, Daniel B; Horvath, Alexander J; Walsh, Teri R; Herrick, Daniel P; Prentiss, Steven J; Powell, Richard J

    2013-11-01

    Lean process improvement techniques are used in industry to improve efficiency and quality while controlling costs. These techniques are less commonly applied in health care. This study assessed the effectiveness of Lean principles on first case on-time operating room starts and quantified effects on resident work hours. Standard process improvement techniques (DMAIC methodology: define, measure, analyze, improve, control) were used to identify causes of delayed vascular surgery first case starts. Value stream maps and process flow diagrams were created. Process data were analyzed with Pareto and control charts. High-yield changes were identified and simulated in computer and live settings prior to implementation. The primary outcome measure was the proportion of on-time first case starts; secondary outcomes included hospital costs, resident rounding time, and work hours. Data were compared with existing benchmarks. Prior to implementation, 39% of first cases started on time. Process mapping identified late resident arrival in preoperative holding as a cause of delayed first case starts. Resident rounding process inefficiencies were identified and changed through the use of checklists, standardization, and elimination of nonvalue-added activity. Following implementation of process improvements, first case on-time starts improved to 71% at 6 weeks (P = .002). Improvement was sustained with an 86% on-time rate at 1 year (P < .001). Resident rounding time was reduced by 33% (from 70 to 47 minutes). At 9 weeks following implementation, these changes generated an opportunity cost potential of $12,582. Use of Lean principles allowed rapid identification and implementation of perioperative process changes that improved efficiency and resulted in significant cost savings. This improvement was sustained at 1 year. Downstream effects included improved resident efficiency with decreased work hours. Copyright © 2013 Society for Vascular Surgery. Published by Mosby, Inc. All

  18. A current profile model for magnetic analysis of the start-up phase of toroidal plasmas driven by electron cyclotron heating and current drive

    International Nuclear Information System (INIS)

    Yoshinaga, T.; Uchida, M.; Tanaka, H.; Maekawa, T.

    2007-01-01

    An estimation model of plasma current density distribution for the start-up phase of toroidal plasmas generated by electron cyclotron heating (ECH) in the low aspect ratio torus experiment device is presented. The model assumes a power law parabolic current profile having seven fitting parameters. Its position, extent and broadness (or steepness) are fitted by adjusting these parameters to the observed magnetic flux signals. The adequacy of the model has been examined and confirmed by comparisons of the reconstructed current profiles and the resultant poloidal flux surfaces with the plasma images at visible light range at various stages of start-up discharges, including both the initial open field phase, the subsequent closed field phase, the current decay phase after ECH is turned off and also by a current-profile limiting experiment. This method may be useful for the study of non-inductive start-up experiments by ECH, where there is no appropriate MHD constraint on the current distribution as that in the full tokamak discharge plasmas

  19. Electron Bernstein wave current drive in the start-up phase of a tokamak discharge

    International Nuclear Information System (INIS)

    Montes, A.; Ludwig, G.O.

    1986-04-01

    Current drive by electron Bernstein waves in the start-up phase of tokamak discharges is studied. A general analytical expression is derived for the figure of merit J/Pd associated with these waves. This is coupled with a ray tracing code, allowing the calculation of the total current generated per unit of incident power in realistic tokamak conditions. The resuts show that the electron Bernstein waves can drive substantial currents even at very low electron temperatures. (Author) [pt

  20. School Start Times for Middle School and High School Students - United States, 2011-12 School Year.

    Science.gov (United States)

    Wheaton, Anne G; Ferro, Gabrielle A; Croft, Janet B

    2015-08-07

    Adolescents who do not get enough sleep are more likely to be overweight; not engage in daily physical activity; suffer from depressive symptoms; engage in unhealthy risk behaviors such as drinking, smoking tobacco, and using illicit drugs; and perform poorly in school. However, insufficient sleep is common among high school students, with less than one third of U.S. high school students sleeping at least 8 hours on school nights. In a policy statement published in 2014, the American Academy of Pediatrics (AAP) urged middle and high schools to modify start times as a means to enable students to get adequate sleep and improve their health, safety, academic performance, and quality of life. AAP recommended that "middle and high schools should aim for a starting time of no earlier than 8:30 a.m.". To assess state-specific distributions of public middle and high school start times and establish a pre-recommendation baseline, CDC and the U.S. Department of Education analyzed data from the 2011-12 Schools and Staffing Survey (SASS). Among an estimated 39,700 public middle, high, and combined schools* in the United States, the average start time was 8:03 a.m. Overall, only 17.7% of these public schools started school at 8:30 a.m. or later. The percentage of schools with 8:30 a.m. or later start times varied greatly by state, ranging from 0% in Hawaii, Mississippi, and Wyoming to more than three quarters of schools in Alaska (76.8%) and North Dakota (78.5%). A school system start time policy of 8:30 a.m. or later provides teenage students the opportunity to achieve the 8.5-9.5 hours of sleep recommended by AAP and the 8-10 hours recommended by the National Sleep Foundation.

  1. Is 8:30 a.m. Still Too Early to Start School? A 10:00 a.m. School Start Time Improves Health and Performance of Students Aged 13–16

    Directory of Open Access Journals (Sweden)

    Paul Kelley

    2017-12-01

    Full Text Available While many studies have shown the benefits of later school starts, including better student attendance, higher test scores, and improved sleep duration, few have used starting times later than 9:00 a.m. Here we report on the implementation and impact of a 10 a.m. school start time for 13 to 16-year-old students. A 4-year observational study using a before-after-before (A-B-A design was carried out in an English state-funded high school. School start times were changed from 8:50 a.m. in study year 0, to 10 a.m. in years 1–2, and then back to 8:50 a.m. in year 3. Measures of student health (absence due to illness and academic performance (national examination results were used for all students. Implementing a 10 a.m. start saw a decrease in student illness after 2 years of over 50% (p < 0.0005 and effect size: Cohen's d = 1.07, and reverting to an 8:50 a.m. start reversed this improvement, leading to an increase of 30% in student illness (p < 0.0005 and Cohen's d = 0.47. The 10:00 a.m. start was associated with a 12% increase in the value-added number of students making good academic progress (in standard national examinations that was significant (<0.0005 and equivalent to 20% of the national benchmark. These results show that changing to a 10:00 a.m. high school start time can greatly reduce illness and improve academic performance. Implementing school start times later than 8:30 a.m., which may address the circadian delay in adolescents' sleep rhythms more effectively for evening chronotypes, appears to have few costs and substantial benefits.

  2. AWAKE starts the equipment installation phase

    CERN Multimedia

    Antonella Del Rosso

    2015-01-01

    AWAKE is the proof-of-principle experiment whose aim is to use protons to generate powerful wakefields to accelerate an electron beam. With accelerator gradients hundreds of times higher than those used in current systems, this technique could revolutionise the field of particle acceleration. Installed in the tunnel previously used by the CNGS facility, AWAKE is completing the service installation phase and will receive the plasma cell in the coming months.   The AWAKE proton line with all the magnets installed. (Image: AWAKE collaboration.) AWAKE is the world’s first proton-driven plasma wakefield acceleration experiment. In AWAKE, a beam of protons from the SPS will be travelling through a plasma cell and this will generate a wakefield that, in turn, will accelerate an electron beam. A laser will ionise the gas in the plasma cell and seed the self-modulation instability that will trigger the wakefield in the plasma. The project aims to prove that the plasma wakefield can be driv...

  3. S-phase cell distribution in the small intestine irradiated at different times of the day. 2. Recovery phase

    Energy Technology Data Exchange (ETDEWEB)

    Becciolini, A; Balzi, M; Cremonini, D; Fabbrica, D [Florence Univ. (Italy). Ist. di Radiologia

    1983-01-01

    Modifications occurring during recovery in the small intestine of animals exposed to the same radiation dose given at different times of the day were evaluated. S-phase cell distribution along the crypts and invertase activity were evaluated to ascertain the functional capacity of epithelial cells. In animals killed between 5 and 6 days after exposure, S-phase cell distribution and functional conditions tended towards normality although recovery was not complete. Labelled cells occurred also at villus junctions, demonstrating limitation in size of the differentiating compartment. This was confirmed by reduced activity of the brush border enzymes. Animals irradiated at the end of the dark period recovered more quickly and efficiently. In this group, labelled cell distribution was almost the same as in the controls starting from 120 h, and invertase activity was also closer to the controls than in any other group.

  4. Soft-Starting Power-Factor Motor Controller

    Science.gov (United States)

    Nola, F. J.

    1983-01-01

    Three-phase power-factor controller with soft start is based on earlier version that does not control starting transients. Additional components serve to turn off "run" command signal and substitute gradual startup command signal during preset startup interval. Improved controller reduces large current surge that usually accompanies starting. Controller applies power smoothly, without causing motor vibrations.

  5. Combination of light and melatonin time cues for phase advancing the human circadian clock.

    Science.gov (United States)

    Burke, Tina M; Markwald, Rachel R; Chinoy, Evan D; Snider, Jesse A; Bessman, Sara C; Jung, Christopher M; Wright, Kenneth P

    2013-11-01

    Photic and non-photic stimuli have been shown to shift the phase of the human circadian clock. We examined how photic and non-photic time cues may be combined by the human circadian system by assessing the phase advancing effects of one evening dose of exogenous melatonin, alone and in combination with one session of morning bright light exposure. Randomized placebo-controlled double-blind circadian protocol. The effects of four conditions, dim light (∼1.9 lux, ∼0.6 Watts/m(2))-placebo, dim light-melatonin (5 mg), bright light (∼3000 lux, ∼7 Watts/m(2))-placebo, and bright light-melatonin on circadian phase was assessed by the change in the salivary dim light melatonin onset (DLMO) prior to and following treatment under constant routine conditions. Melatonin or placebo was administered 5.75 h prior to habitual bedtime and 3 h of bright light exposure started 1 h prior to habitual wake time. Sleep and chronobiology laboratory environment free of time cues. Thirty-six healthy participants (18 females) aged 22 ± 4 y (mean ± SD). Morning bright light combined with early evening exogenous melatonin induced a greater phase advance of the DLMO than either treatment alone. Bright light alone and melatonin alone induced similar phase advances. Information from light and melatonin appear to be combined by the human circadian clock. The ability to combine circadian time cues has important implications for understanding fundamental physiological principles of the human circadian timing system. Knowledge of such principles is important for designing effective countermeasures for phase-shifting the human circadian clock to adapt to jet lag, shift work, and for designing effective treatments for circadian sleep-wakefulness disorders.

  6. Bottleneck congestion and distribution of work start times: The economics of staggered work hours revisited

    OpenAIRE

    Takayama, Yuki

    2014-01-01

    Since the seminal work of Henderson (1981), a number of studies examined the effect of staggered work hours by analyzing models of work start time choice that consider the trade-off between negative congestion externalities and positive production externalities. However, these studies described traffic congestion using flow congestion models. This study develops a model of work start time choice with bottleneck congestion and discloses the intrinsic properties of the model. To this end, this ...

  7. Estimation of Saturation Flow Rate and Start-Up Lost Time for Signal Timing Based on Headway Distribution

    Directory of Open Access Journals (Sweden)

    Yi Zhao

    2015-01-01

    Full Text Available This study aimed to calibrate saturation flow rate (SFR and start-up lost time (SLT when developing signal timing. In current commonly used methods, SFR for one given lane is usually calibrated from many subjective adjustment factors and a fixed result. SLT is calculated based on the fixed SFR, which prevents local applications in China. Considering the importance of traffic behavior (headway in determining SFR and SLT, this study started from headway distribution and attempted to specify the relationships between headway and vehicle position directly. A common intersection in Nanjing, China, was selected to implement field study and data from 920 queues was collected. Headway distribution was explored and the 78th percentile of headway at each position was selected to build model. Based on the developed relationships, SFR and SLT were calibrated. The results showed that SFR and SLT were correlated with queue length. Moreover, the results showed that it was difficult to reach saturated state even with a long queue length. This paper provides a new perspective on calibrating important parameters in signal timing, which will be useful for traffic agencies to complete signal timing by making the process simpler.

  8. Exploratory analysis of time from HIV diagnosis to ART start, factors ...

    African Journals Online (AJOL)

    Background: the HIV care in Ethiopia has reached 79% coverage. The timeliness of the care provided at the different levels in the course of the disease starting from knowing HIV positive status to ART initiation is not well known. This study intends to explore the timing of the care seeking, the care provision and associated ...

  9. A single center analysis of factors influencing study start-up timeline in clinical trials.

    Science.gov (United States)

    Krafcik, Brianna M; Doros, Gheorghe; Malikova, Marina A

    2017-11-01

    Efficient start-up phase in clinical trials is crucial to execution. The goal was to determine factors contributing to delays. The start-up milestones were assessed for 38 studies and analyzed. Total start-up time was shorter for following studies: device trials, no outsourcing, fewer ancillary services used and in interventional versus observational designs. The use of a centralized Institutional Review Board (IRB) versus a local IRB reduced time to approval. Studies that never enrolled took longer on average to finalize their budget/contract, and obtain IRB than ones that did enroll. Different features of clinical trials can affect timeline of start-up process. An understanding of the impact of each feature allows for optimization.

  10. School start time influences melatonin and cortisol levels in children and adolescents - a community-based study.

    Science.gov (United States)

    Carissimi, Alicia; Martins, Alessandra Castro; Dresch, Fabiane; da Silva, Lilian Corrêa; Zeni, Cristian Patrick; Hidalgo, Maria Paz

    2016-01-01

    School start time influences sleep parameters. Differences between circadian sleep parameters on weekends and weekdays have been associated with obesity, sleep, and psychiatric disorders. Moreover, circadian rhythm dysregulation affects the secretion of some hormones, such as melatonin and cortisol. In the current study, we investigate the effect of school start time on cortisol and melatonin levels in a community sample of Brazilian children and adolescents. This was a cross-sectional study of 454 students (mean age, 12.81 ± 2.56 years; 58.6% female). From this sample, 80 participants were randomly selected for saliva collection to measure melatonin and cortisol levels. Circadian sleep parameters were assessed by self-reported sleep and wake up schedules and the Morningness-Eveningness Questionnaire. The outcomes, salivary melatonin and cortisol levels, were measured in morning, afternoon and night saliva samples, and behavior problems were assessed using the Child Behavior Checklist (CBCL). The main results revealed that morning school start time decreased the secretion of melatonin. Morning melatonin levels were significantly positively correlated with the sleep midpoint on weekdays and on weekends. Afternoon melatonin levels were positively correlated with the sleep midpoint on weekends in the morning school students. Conversely, in the afternoon school students, night melatonin levels were negatively correlated with the sleep midpoint on weekdays. Cortisol secretion did not correlate with circadian sleep parameters in any of the school time groups. In conclusion, school start time influences melatonin secretion, which correlated with circadian sleep parameters. This correlation depends on the presence of psychiatric symptoms. Our findings emphasize the importance of drawing attention to the influence of school start time on the circadian rhythm of children and adolescents.

  11. Law-based arguments and messages to advocate for later school start time policies in the United States.

    Science.gov (United States)

    Lee, Clark J; Nolan, Dennis M; Lockley, Steven W; Pattison, Brent

    2017-12-01

    The increasing scientific evidence that early school start times are harmful to the health and safety of teenagers has generated much recent debate about changing school start times policies for adolescent students. Although efforts to promote and implement such changes have proliferated in the United States in recent years, they have rarely been supported by law-based arguments and messages that leverage the existing legal infrastructure regulating public education and child welfare in the United States. Furthermore, the legal bases to support or resist such changes have not been explored in detail to date. This article provides an overview of how law-based arguments and messages can be constructed and applied to advocate for later school start time policies in US public secondary schools. The legal infrastructure impacting school start time policies in the United States is briefly reviewed, including descriptions of how government regulates education, what legal obligations school officials have concerning their students' welfare, and what laws and public policies currently exist that address adolescent sleep health and safety. On the basis of this legal infrastructure, some hypothetical examples of law-based arguments and messages that could be applied to various types of advocacy activities (eg, litigation, legislative and administrative advocacy, media and public outreach) to promote later school start times are discussed. Particular consideration is given to hypothetical arguments and messages aimed at emphasizing the consistency of later school start time policies with existing child welfare law and practices, legal responsibilities of school officials and governmental authorities, and societal values and norms. Copyright © 2017 National Sleep Foundation. Published by Elsevier Inc. All rights reserved.

  12. Engaging the community in the process of changing school start times: experience of the Cherry Creek School District.

    Science.gov (United States)

    Meltzer, Lisa J; McNally, Janise; Plog, Amy E; Siegfried, Scott A

    2017-12-01

    Despite growing evidence of the positive impact of later school start times on adolescent health and academic outcomes, relatively few districts have changed start times due to concerns about transportation, child care, and athletics/extracurricular activities. This paper provides a case study of the Cherry Creek School District's (CCSD) successful efforts to change start times. The CCSD is a diverse district with an enrollment of almost 55,000 students in suburban Denver. As part of CCSD's strategic plan, a multi-disciplinary task force was formed to examine the impact of start times on student achievement, and recommend a start time schedule driven by best practices on adolescent sleep patterns, balanced with family and community needs. Over 18 months the task force's work included engaging the community through meetings, as well as conducting a large survey (n = 24,574) of parents, teachers, and students, and gathering online feedback. An iterative process utilized feedback at every stage to refine the final recommendation given to the Board of Education. Survey results, implementation considerations, outcome evaluation plans, and lessons learned are discussed. Copyright © 2017 National Sleep Foundation. Published by Elsevier Inc. All rights reserved.

  13. Timing of international market entry of UK and German high-tech start-ups

    OpenAIRE

    Bürgel, Oliver; Fier, Andreas; Licht, Georg; Murray, Gordon

    2001-01-01

    We examine the impact of technological product advantages, prior international experience of the management, firm size and age, country differences, and sunk costs as determinants of the timing of international market entry. The timing of internationalisation is analysed using ?event history analysis? for 600 British and German start-up companies in high-technology industries. The results indicate that the incidence of internationalization increases over time. For the majority of new firms th...

  14. The Effect of an Altitude Training Camp on Swimming Start Time and Loaded Squat Jump Performance.

    Science.gov (United States)

    García-Ramos, Amador; Štirn, Igor; Padial, Paulino; Argüelles-Cienfuegos, Javier; De la Fuente, Blanca; Calderón, Carmen; Bonitch-Góngora, Juan; Tomazin, Katja; Strumbelj, Boro; Strojnik, Vojko; Feriche, Belén

    2016-01-01

    This study evaluated the influence of an altitude training (AT) camp on swimming start time and loaded squat jump performance. To accomplish this goal, 13 international swimmers (8 women, 5 men) were allocated to both the control (Sea Level Training, SLT) and experimental conditions (AT, 2320 m above sea level) that were separated by a one year period. All tests (15 m freestyle swimming start and loaded squat jumps with additional loads of 25%, 50%, 75%, and 100% of swimmers' body weight) were performed before and after a concurrent 3-week strength and endurance training program prescribed by the national coach. Following the SLT camp, significant impairments in swimming start times to 10 (+3.1%) and 15 m (+4.0%) were observed (P 0.05). Trivial changes in peak velocity were obtained during the loaded squat jump after both training periods (effect sizes: training high-living high strategy concurrent training of 3 weeks does not adversely affect swimming start time and loaded squat jump performance in high level swimmers, but further studies are necessary to assess the effectiveness of power-oriented resistance training in the development of explosive actions.

  15. Application of intelligent soft start in asynchronous motor

    Science.gov (United States)

    Du, Xue; Ye, Ying; Wang, Yuelong; Peng, Lei; Zhang, Suying

    2018-05-01

    The starting way of three phase asynchronous motor has full voltage start and step-down start. Direct starting brings large current impact, causing excessive local temperature to the power grid and larger starting torque will also impact the motor equipment and affect the service life of the motor. Aim at the problem of large current and torque caused by start-up, an intelligent soft starter is proposed. Through the application of intelligent soft start on asynchronous motor, highlights its application advantage in motor control.

  16. Starting ART following cryptococcal meningitis:The optimal time has yet to be defined

    Directory of Open Access Journals (Sweden)

    T A Bicanic

    2013-09-01

    Full Text Available Ever since the public sector rollout of antiretroviral therapy (ART in 2004, the question of the optimal time to start ART following diagnosis of an opportunistic infection has aroused controversy among South African HIV clinicians and researchers.

  17. Vortex Formation and Acceleration of a Fish-Inspired Robot Performing Starts from Rest

    Science.gov (United States)

    Devoria, Adam; Bapst, Jonathan; Ringuette, Matthew

    2009-11-01

    We investigate the unsteady flow of a fish-inspired robot executing starts from rest, with the objective of understanding the connection among the kinematics, vortex formation, and acceleration performance. Several fish perform ``fast starts,'' where the body bends into a ``C'' or ``S'' shape while turning (phase I), followed by a straightening of the body and caudal fin and a linear acceleration (phase II). The resulting highly 3-D, unsteady vortex formation and its relationship to the acceleration are not well understood. The self-propelled robotic model contains motor-driven joints with programmable motion to emulate phase II of a simplified C-start. The experiments are conducted in a water tank, and the model is constrained to 1 direction along rails. The velocity is measured using digital particle image velocimetry (DPIV) in multiple planes. Vortex boundaries are identified using the finite-time Lyapunov exponent, then the unsteady vortex circulation is computed. The thrust is estimated from the identified vortices, and correlated with the circulation and model acceleration for different kinematics.

  18. Setting Adolescents up for Success: Promoting a Policy to Delay High School Start Times

    Science.gov (United States)

    Barnes, Margaux; Davis, Krista; Mancini, Mackenzie; Ruffin, Jasmine; Simpson, Tina; Casazza, Krista

    2016-01-01

    Background: A unique biological shift in sleep cycles occurs during adolescence causing later sleep and wake times. This shift is not matched by a concurrent modification in school start times, resulting in sleep curtailment for a large majority of adolescents. Chronic inadequate sleep is associated with poor academic performance including…

  19. The rewritable effects of bonded magnet for large starting torque and high efficiency in the small power single-phase written pole motor

    Science.gov (United States)

    Choi, Jae-Hak; Lee, Sung-Ho

    2009-04-01

    This paper presents a single-phase written pole motor using a bonded ring magnet for the small power home application. The motor has an exciter pole structure inside the stator and hybrid characteristics of an induction motor and permanent magnet motor. The design parameters and operating characteristics of the hybrid concept motor are investigated to increase starting torque and efficiency, which is most important for the small power home application. Larger starting torque and higher efficiency than those of the conventional induction motor could be obtained by using the rewritable characteristics of bonded magnet on the starting and running conditions.

  20. A Studio Based Approach to Enhancing Decision Making in Sme Start-Up

    NARCIS (Netherlands)

    Sol, H G; Ejiri, A.H.; Nabukenya, J.

    2011-01-01

    The start-up phase plays an important role in the success and survival of many enterprises, which greatly depends on adequate and timely services for decision making. However, deciding to startup a mining Small and Medium Enterprise (SME) is a challenging task for many entrepreneurs in Uganda.

  1. Principles of fluid management and stewardship in septic shock: it is time to consider the four D's and the four phases of fluid therapy.

    Science.gov (United States)

    Malbrain, Manu L N G; Van Regenmortel, Niels; Saugel, Bernd; De Tavernier, Brecht; Van Gaal, Pieter-Jan; Joannes-Boyau, Olivier; Teboul, Jean-Louis; Rice, Todd W; Mythen, Monty; Monnet, Xavier

    2018-05-22

    In patients with septic shock, the administration of fluids during initial hemodynamic resuscitation remains a major therapeutic challenge. We are faced with many open questions regarding the type, dose and timing of intravenous fluid administration. There are only four major indications for intravenous fluid administration: aside from resuscitation, intravenous fluids have many other uses including maintenance and replacement of total body water and electrolytes, as carriers for medications and for parenteral nutrition. In this paradigm-shifting review, we discuss different fluid management strategies including early adequate goal-directed fluid management, late conservative fluid management and late goal-directed fluid removal. In addition, we expand on the concept of the "four D's" of fluid therapy, namely drug, dosing, duration and de-escalation. During the treatment of patients with septic shock, four phases of fluid therapy should be considered in order to provide answers to four basic questions. These four phases are the resuscitation phase, the optimization phase, the stabilization phase and the evacuation phase. The four questions are "When to start intravenous fluids?", "When to stop intravenous fluids?", "When to start de-resuscitation or active fluid removal?" and finally "When to stop de-resuscitation?" In analogy to the way we handle antibiotics in critically ill patients, it is time for fluid stewardship.

  2. Single-phase and two-phase anaerobic digestion of fruit and vegetable waste: Comparison of start-up, reactor stability and process performance

    Energy Technology Data Exchange (ETDEWEB)

    Ganesh, Rangaraj [INRA, UR50, Laboratoire de Biotechnologie de l’Environnement, Avenue des Etangs, Narbonne F-11100 (France); Torrijos, Michel, E-mail: michel.torrijos@supagro.inra.fr [INRA, UR50, Laboratoire de Biotechnologie de l’Environnement, Avenue des Etangs, Narbonne F-11100 (France); Sousbie, Philippe [INRA, UR50, Laboratoire de Biotechnologie de l’Environnement, Avenue des Etangs, Narbonne F-11100 (France); Lugardon, Aurelien [Naskeo Environnment, 52 rue Paul Vaillant Couturier, F-92240 Malakoff (France); Steyer, Jean Philippe; Delgenes, Jean Philippe [INRA, UR50, Laboratoire de Biotechnologie de l’Environnement, Avenue des Etangs, Narbonne F-11100 (France)

    2014-05-01

    Highlights: • Single-phase and two-phase systems were compared for fruit and vegetable waste digestion. • Single-phase digestion produced a methane yield of 0.45 m{sup 3} CH{sub 4}/kg VS and 83% VS removal. • Substrate solubilization was high in acidification conditions at 7.0 kg VS/m{sup 3} d and pH 5.5–6.2. • Energy yield was lower by 33% for two-phase system compared to the single-phase system. • Simple and straight-forward operation favored single phase process over two-phase process. - Abstract: Single-phase and two-phase digestion of fruit and vegetable waste were studied to compare reactor start-up, reactor stability and performance (methane yield, volatile solids reduction and energy yield). The single-phase reactor (SPR) was a conventional reactor operated at a low loading rate (maximum of 3.5 kg VS/m{sup 3} d), while the two-phase system consisted of an acidification reactor (TPAR) and a methanogenic reactor (TPMR). The TPAR was inoculated with methanogenic sludge similar to the SPR, but was operated with step-wise increase in the loading rate and with total recirculation of reactor solids to convert it into acidification sludge. Before each feeding, part of the sludge from TPAR was centrifuged, the centrifuge liquid (solubilized products) was fed to the TPMR and centrifuged solids were recycled back to the reactor. Single-phase digestion produced a methane yield of 0.45 m{sup 3} CH{sub 4}/kg VS fed and VS removal of 83%. The TPAR shifted to acidification mode at an OLR of 10.0 kg VS/m{sup 3} d and then achieved stable performance at 7.0 kg VS/m{sup 3} d and pH 5.5–6.2, with very high substrate solubilization rate and a methane yield of 0.30 m{sup 3} CH{sub 4}/kg COD fed. The two-phase process was capable of high VS reduction, but material and energy balance showed that the single-phase process was superior in terms of volumetric methane production and energy yield by 33%. The lower energy yield of the two-phase system was due to the loss of

  3. Single-phase and two-phase anaerobic digestion of fruit and vegetable waste: Comparison of start-up, reactor stability and process performance

    International Nuclear Information System (INIS)

    Ganesh, Rangaraj; Torrijos, Michel; Sousbie, Philippe; Lugardon, Aurelien; Steyer, Jean Philippe; Delgenes, Jean Philippe

    2014-01-01

    Highlights: • Single-phase and two-phase systems were compared for fruit and vegetable waste digestion. • Single-phase digestion produced a methane yield of 0.45 m 3 CH 4 /kg VS and 83% VS removal. • Substrate solubilization was high in acidification conditions at 7.0 kg VS/m 3 d and pH 5.5–6.2. • Energy yield was lower by 33% for two-phase system compared to the single-phase system. • Simple and straight-forward operation favored single phase process over two-phase process. - Abstract: Single-phase and two-phase digestion of fruit and vegetable waste were studied to compare reactor start-up, reactor stability and performance (methane yield, volatile solids reduction and energy yield). The single-phase reactor (SPR) was a conventional reactor operated at a low loading rate (maximum of 3.5 kg VS/m 3 d), while the two-phase system consisted of an acidification reactor (TPAR) and a methanogenic reactor (TPMR). The TPAR was inoculated with methanogenic sludge similar to the SPR, but was operated with step-wise increase in the loading rate and with total recirculation of reactor solids to convert it into acidification sludge. Before each feeding, part of the sludge from TPAR was centrifuged, the centrifuge liquid (solubilized products) was fed to the TPMR and centrifuged solids were recycled back to the reactor. Single-phase digestion produced a methane yield of 0.45 m 3 CH 4 /kg VS fed and VS removal of 83%. The TPAR shifted to acidification mode at an OLR of 10.0 kg VS/m 3 d and then achieved stable performance at 7.0 kg VS/m 3 d and pH 5.5–6.2, with very high substrate solubilization rate and a methane yield of 0.30 m 3 CH 4 /kg COD fed. The two-phase process was capable of high VS reduction, but material and energy balance showed that the single-phase process was superior in terms of volumetric methane production and energy yield by 33%. The lower energy yield of the two-phase system was due to the loss of energy during hydrolysis in the TPAR and the

  4. The Effect of an Altitude Training Camp on Swimming Start Time and Loaded Squat Jump Performance.

    Directory of Open Access Journals (Sweden)

    Amador García-Ramos

    Full Text Available This study evaluated the influence of an altitude training (AT camp on swimming start time and loaded squat jump performance. To accomplish this goal, 13 international swimmers (8 women, 5 men were allocated to both the control (Sea Level Training, SLT and experimental conditions (AT, 2320 m above sea level that were separated by a one year period. All tests (15 m freestyle swimming start and loaded squat jumps with additional loads of 25%, 50%, 75%, and 100% of swimmers' body weight were performed before and after a concurrent 3-week strength and endurance training program prescribed by the national coach. Following the SLT camp, significant impairments in swimming start times to 10 (+3.1% and 15 m (+4.0% were observed (P 0.05. Trivial changes in peak velocity were obtained during the loaded squat jump after both training periods (effect sizes: < 0.20. Based on these results we can conclude that a traditional training high-living high strategy concurrent training of 3 weeks does not adversely affect swimming start time and loaded squat jump performance in high level swimmers, but further studies are necessary to assess the effectiveness of power-oriented resistance training in the development of explosive actions.

  5. Delaying Middle School and High School Start Times Promotes Student Health and Performance: An American Academy of Sleep Medicine Position Statement.

    Science.gov (United States)

    Watson, Nathaniel F; Martin, Jennifer L; Wise, Merrill S; Carden, Kelly A; Kirsch, Douglas B; Kristo, David A; Malhotra, Raman K; Olson, Eric J; Ramar, Kannan; Rosen, Ilene M; Rowley, James A; Weaver, Terri E; Chervin, Ronald D

    2017-04-15

    During adolescence, internal circadian rhythms and biological sleep drive change to result in later sleep and wake times. As a result of these changes, early middle school and high school start times curtail sleep, hamper a student's preparedness to learn, negatively impact physical and mental health, and impair driving safety. Furthermore, a growing body of evidence shows that delaying school start times positively impacts student achievement, health, and safety. Public awareness of the hazards of early school start times and the benefits of later start times are largely unappreciated. As a result, the American Academy of Sleep Medicine is calling on communities, school boards, and educational institutions to implement start times of 8:30 AM or later for middle schools and high schools to ensure that every student arrives at school healthy, awake, alert, and ready to learn. © 2017 American Academy of Sleep Medicine

  6. Nuclear power: time to start again

    International Nuclear Information System (INIS)

    Rezak, W.D.

    2004-01-01

    This paper presents data which support the construction and operating successes enjoyed by energy companies that operate nuclear power plants in the US. The result is that the US nuclear industry is alive and well. Perhaps it's time to start anew the building of nuclear power plants. Over 20% of the electricity generated in the United States comes from nuclear power plants. An adequate, reliable supply of reasonably priced electric energy is not a consequence of an expanding economy and gross national product; it is an absolute necessity before such expansion can occur. It is hard to imagine any aspect of our business or personal lives not, in some way, dependent upon electricity. All over the world (in over 30 countries) nuclear power is a low-cost, secure, safe, dependable, and environmentally friendly form of electric power generation. Nuclear plants in these countries are built in six to eight years using technology developed in the US, with good performance and safety records. This treatise addresses the success experienced by the US nuclear industry over the last 40 years, and makes the case that this reliable, cost-competitive source of electric power can help support the economic engine of the country and help prevent experiences like the recent crises in California and the Northeast. Successful operation of nuclear facilities is determined by examining capacity or load factors. Load factor is the percentage of design generating capacity that a power plant actually produces over the course of a year's operation. This paper makes the case that these operating performance indicators warrant renewed consideration of the nuclear option. Usage of electricity in the US now approaches total generating capacity. The Nuclear Regulatory Commission has pre-approved construction and operating licenses for several nuclear plant designs. State public service commissions are beginning to understand that dramatic reform is required. The economy is recovering and inflation

  7. Effect of altering starting length and activation timing of muscle on fiber strain and muscle damage.

    Science.gov (United States)

    Butterfield, Timothy A; Herzog, Walter

    2006-05-01

    Muscle strain injuries are some of the most frequent injuries in sports and command a great deal of attention in an effort to understand their etiology. These injuries may be the culmination of a series of subcellular events accumulated through repetitive lengthening (eccentric) contractions during exercise, and they may be influenced by a variety of variables including fiber strain magnitude, peak joint torque, and starting muscle length. To assess the influence of these variables on muscle injury magnitude in vivo, we measured fiber dynamics and joint torque production during repeated stretch-shortening cycles in the rabbit tibialis anterior muscle, at short and long muscle lengths, while varying the timing of activation before muscle stretch. We found that a muscle subjected to repeated stretch-shortening cycles of constant muscle-tendon unit excursion exhibits significantly different joint torque and fiber strains when the timing of activation or starting muscle length is changed. In particular, measures of fiber strain and muscle injury were significantly increased by altering activation timing and increasing the starting length of the muscle. However, we observed differential effects on peak joint torque during the cyclic stretch-shortening exercise, as increasing the starting length of the muscle did not increase torque production. We conclude that altering activation timing and muscle length before stretch may influence muscle injury by significantly increasing fiber strain magnitude and that fiber dynamics is a more important variable than muscle-tendon unit dynamics and torque production in influencing the magnitude of muscle injury.

  8. Delayed high school start times later than 8:30am and impact on graduation rates and attendance rates.

    Science.gov (United States)

    McKeever, Pamela Malaspina; Clark, Linda

    2017-04-01

    The first purpose of this study was to investigate changes in high school graduation rates with a delayed school start time of later than 8:30am. The second aim of the study was to analyze the association between a delayed high school start time later than 8:30am and attendance rates. In the current study, a pre-post design using a repeated-measures analysis of variance was used to examine changes in attendance and graduation rates 2 years after a delayed start was implemented. Public high schools from 8 school districts (n=29 high schools) located throughout 7 different states. Schools were identified using previous research from the Children's National Medical Center's Division of Sleep Medicine Research Team. A total membership of more than 30,000 high school students enrolled in the 29 schools identified by the Children's National Medical Center's Research Team. A pre-post design was used for a within-subject design, controlling for any school-to-school difference in the calculation of the response variable. This is the recommended technique for a study that may include data with potential measurement error. Findings from this study linked a start time of later than 8:30am to improved attendance rates and graduation rates. Attendance rates and graduation rates significantly improved in schools with delayed start times of 8:30am or later. School officials need to take special notice that this investigation also raises questions about whether later start times are a mechanism for closing the achievement gap due to improved graduation rates. Copyright © 2017 National Sleep Foundation. Published by Elsevier Inc. All rights reserved.

  9. Gas Turbine Engine Starting Applicated on TV2-117 Turboshaft

    Directory of Open Access Journals (Sweden)

    R. M. Catana

    2017-10-01

    Full Text Available The paper presents the examination of two different types of engine starting configurations, applicated on TV2-117A turboshaft, running into the test bench. The first type of starting configuration is a normal starting, with the engine connected to the dynamometer which controls the free turbine speed by the dynamometer load. The second type of starting is a different one, the engine is not connected with the dynamometer, therefore it results that there is no control of the free turbine speed from the dynamometer, only from the engine but in particular conditions. To achieve the starting phase an instrumentation scheme is created, to control and monitor the engine, and a starting sequence with all the parameters, confirmations and commands that are involved into the starting phase. The engine starting is performed by the test bench operating system, composed of an acquisition system and a programmable controller, wherewith is running the starting sequence.

  10. Optofluidic time-stretch quantitative phase microscopy.

    Science.gov (United States)

    Guo, Baoshan; Lei, Cheng; Wu, Yi; Kobayashi, Hirofumi; Ito, Takuro; Yalikun, Yaxiaer; Lee, Sangwook; Isozaki, Akihiro; Li, Ming; Jiang, Yiyue; Yasumoto, Atsushi; Di Carlo, Dino; Tanaka, Yo; Yatomi, Yutaka; Ozeki, Yasuyuki; Goda, Keisuke

    2018-03-01

    Innovations in optical microscopy have opened new windows onto scientific research, industrial quality control, and medical practice over the last few decades. One of such innovations is optofluidic time-stretch quantitative phase microscopy - an emerging method for high-throughput quantitative phase imaging that builds on the interference between temporally stretched signal and reference pulses by using dispersive properties of light in both spatial and temporal domains in an interferometric configuration on a microfluidic platform. It achieves the continuous acquisition of both intensity and phase images with a high throughput of more than 10,000 particles or cells per second by overcoming speed limitations that exist in conventional quantitative phase imaging methods. Applications enabled by such capabilities are versatile and include characterization of cancer cells and microalgal cultures. In this paper, we review the principles and applications of optofluidic time-stretch quantitative phase microscopy and discuss its future perspective. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. The backstroke swimming start: state of the art.

    Science.gov (United States)

    de Jesus, Karla; de Jesus, Kelly; Fernandes, Ricardo J; Vilas-Boas, João Paulo; Sanders, Ross

    2014-09-29

    As sprint swimming events can be decided by margins as small as .01 s, thus, an effective start is essential. This study reviews and discusses the 'state of the art' literature regarding backstroke start biomechanics from 23 documents. These included two swimming specific publications, eight peer-reviewed journal articles, three from the Biomechanics and Medicine in Swimming Congress series, eight from the International Society of Biomechanics in Sports Conference Proceedings, one from a Biomechanics Congress and one academic (PhD) thesis. The studies had diverse aims, including swimmers' proficiency levels and data collection settings. There was no single consensus for defining phase descriptions; and kinematics, kinetics and EMG approaches were implemented in laboratory settings. However, researchers face great challenges in improving methods of quantifying valid, reliable and accurate data between laboratory and competition conditions. For example, starting time was defined from the starting signal to distances as disparate as ∼5 m to 22.86 m in several studies. Due to recent rule changes, some of the research outcomes now refer to obsolete backstroke start techniques, and only a few studies considered the actual international rules. This literature review indicated that further research is required, in both laboratory and competition settings focusing on the combined influences of the current rules and block configuration on backstroke starting performances.

  12. The Static Eccentricity Fault Diagnosis in Time Domain at Line Start Permanent Magnet Synchronous Motor

    OpenAIRE

    DOGAN, Zafer

    2016-01-01

    Recently, Line Start Permanent Magnet Synchronous Motor have been commonly utilized in industrial areas because of their high efficiency. Motor faults during operation cause losses of production and high maintenance and repair expenditures. In this study, the effect of static eccentricity fault on line start permanent magnet synchronous motor was investigated. The simulation models of motor belonging to healthy and fault status were formed via Finite Elements Method. The analyses in time doma...

  13. Breath-holding times in various phases of respiration and effect of respiratory training in lung cancer patients.

    Science.gov (United States)

    Tibdewal, Anil; Munshi, Anusheel; Pathak, Rima; Misra, Shagun; Daptardar, Anuradha; Singh, Vincent; Agarwal, Jai Prakash

    2015-08-01

    Breath-holding (BH) technique is used for reducing the intrafraction-tumour motion in mobile lung tumours treated with radiotherapy (RT). There is paucity of literature evaluating differences in BH times in various phases of respiration in patients with lung cancer. One hundred consecutive patients with lung cancer planned for radical RT/chemoradiation were accrued in the study. Eighty-seven patients were eligible for analysis at RT conclusion. Baseline pulmonary function test (PFT) were performed in all patients, and respiratory training was given from the day of RT planning. Deep inspiration breath hold (DIBH), deep expiration breath hold (DEBH) and mid-ventilation breath hold (MVBH) were recorded manually with a stopwatch for each patient at four time points (RT planning/baseline, RT starting, during RT and RT conclusion). Median DIBH times at RT planning, RT starting, during RT and RT conclusion were 21.2, 20.6, 20.1 and 21.1 s, respectively. The corresponding median DEBH and MVBH times were 16.3, 18.2, 18.3, 18.5 s and 19.9, 20.5, 21.3, 22.1 s, respectively. Respiratory training increased MVBH time at RT conclusion compared to baseline, which was statistically significant (19.9-22.1 s, P = 0.002). DIBH or DEBH times were stable at various time points with neither a significant improvement nor decline. Among various patient and tumour factors Forced Vital Capacity pre-bronchodilation (FVCpre ) was the only factor that consistently predicted DIBH, DEBH and MVBH at all four time points with P value phases of respiration. Respiratory training improved MVBH time while consistently maintaining DIBH and DEBH times throughout the course of radiotherapy. © 2015 The Royal Australian and New Zealand College of Radiologists.

  14. The use of knowledge-based Genetic Algorithm for starting time optimisation in a lot-bucket MRP

    Science.gov (United States)

    Ridwan, Muhammad; Purnomo, Andi

    2016-01-01

    In production planning, Material Requirement Planning (MRP) is usually developed based on time-bucket system, a period in the MRP is representing the time and usually weekly. MRP has been successfully implemented in Make To Stock (MTS) manufacturing, where production activity must be started before customer demand is received. However, to be implemented successfully in Make To Order (MTO) manufacturing, a modification is required on the conventional MRP in order to make it in line with the real situation. In MTO manufacturing, delivery schedule to the customers is defined strictly and must be fulfilled in order to increase customer satisfaction. On the other hand, company prefers to keep constant number of workers, hence production lot size should be constant as well. Since a bucket in conventional MRP system is representing time and usually weekly, hence, strict delivery schedule could not be accommodated. Fortunately, there is a modified time-bucket MRP system, called as lot-bucket MRP system that proposed by Casimir in 1999. In the lot-bucket MRP system, a bucket is representing a lot, and the lot size is preferably constant. The time to finish every lot could be varying depends on due date of lot. Starting time of a lot must be determined so that every lot has reasonable production time. So far there is no formal method to determine optimum starting time in the lot-bucket MRP system. Trial and error process usually used for it but some time, it causes several lots have very short production time and the lot-bucket MRP would be infeasible to be executed. This paper presents the use of Genetic Algorithm (GA) for optimisation of starting time in a lot-bucket MRP system. Even though GA is well known as powerful searching algorithm, however, improvement is still required in order to increase possibility of GA in finding optimum solution in shorter time. A knowledge-based system has been embedded in the proposed GA as the improvement effort, and it is proven that the

  15. Advanced Start of Combustion Sensor Phases I and II-A: Feasibility Demonstration, Design and Optimization

    Energy Technology Data Exchange (ETDEWEB)

    Chad Smutzer

    2010-01-31

    Homogeneous Compressed Charge Ignition (HCCI) has elevated the need for Start of Combustion (SOC) sensors. HCCI engines have been the exciting focus of engine research recently, primarily because HCCI offers higher thermal efficiency than the conventional Spark Ignition (SI) engines and significantly lower NOx and soot emissions than conventional Compression Ignition (CI) engines, and could be fuel neutral. HCCI has the potential to unify all the internal combustion engine technology to achieve the high-efficiency, low-emission goal. However, these advantages do not come easy. It is well known that the problems encountered with HCCI combustion center on the difficulty of controlling the Start of Combustion. TIAX has an SOC sensor under development which has shown promise. In previous work, including a DOE-sponsored SBIR project, TIAX has developed an accelerometer-based method which was able to determine SOC within a few degrees crank angle for a range of operating conditions. A signal processing protocol allows reconstruction of the combustion pressure event signal imbedded in the background engine vibration recorded by the accelerometer. From this reconstructed pressure trace, an algorithm locates the SOC. This SOC sensor approach is nonintrusive, rugged, and is particularly robust when the pressure event is strong relative to background engine vibration (at medium to high engine load). Phase I of this project refined the previously developed technology with an engine-generic and robust algorithm. The objective of the Phase I research was to answer two fundamental questions: Can the accelerometer-based SOC sensor provide adequate SOC event capture to control an HCCI engine in a feedback loop? And, will the sensor system meet cost, durability, and software efficiency (speed) targets? Based upon the results, the answer to both questions was 'YES'. The objective of Phase II-A was to complete the parameter optimization of the SOC sensor prototype in order

  16. Effects of school start time on students' sleep duration, daytime sleepiness, and attendance: a meta-analysis.

    Science.gov (United States)

    Bowers, Jennifer M; Moyer, Anne

    2017-12-01

    Research conducted over the past three decades finds that many children and adolescents do not meet recommended sleep guidelines. Lack of sleep is a predictor of a number of consequences, including issues at school such as sleepiness and tardiness. Considering the severity of this public health issue, it is essential to understand more about the factors that may compromise children's and adolescents' sleep. This meta-analysis examined the effects of school start time (SST) on sleep duration of students by aggregating the results of five longitudinal studies and 15 cross-sectional comparison group studies. Results indicated that later starting school times are associated with longer sleep durations. Additionally, later start times were associated with less daytime sleepiness (7 studies) and tardiness to school (3 studies). However, methodological considerations, such as a need for more longitudinal primary research, lead to a cautious interpretation. Overall, this systematic analysis of SST studies suggests that delaying SST is associated with benefits for students' sleep and, thus, their general well-being. Copyright © 2017 National Sleep Foundation. Published by Elsevier Inc. All rights reserved.

  17. Using Start/End Timings of Spectral Transitions Between Phonemes in Concatenative Speech Synthesis

    OpenAIRE

    Toshio Hirai; Seiichi Tenpaku; Kiyohiro Shikano

    2002-01-01

    The definition of "phoneme boundary timing" in a speech corpus affects the quality of concatenative speech synthesis systems. For example, if the selected speech unit is not appropriately match to the speech unit of the required phoneme environment, the quality may be degraded. In this paper, a dynamic segment boundary defi- nition is proposed. In the definition, the concatenation point is chosen from the start or end timings of spectral transition depending on the phoneme environment at the ...

  18. A Boom Time for Education Start-Ups

    Science.gov (United States)

    DeSantis, Nick

    2012-01-01

    Harsh economic realities mean trouble for college leaders. But where administrators perceive an impending crisis, investors increasingly see opportunity. In recent years, venture capitalists have poured millions into education-technology start-ups, trying to cash in on a market they see as ripe for a digital makeover. And lately, those wagers have…

  19. Random-start ovarian stimulation in women desiring elective cryopreservation of oocytes.

    Science.gov (United States)

    Pereira, Nigel; Voskuilen-Gonzalez, Anna; Hancock, Kolbe; Lekovich, Jovana P; Schattman, Glenn L; Rosenwaks, Zev

    2017-10-01

    The current study investigates the utility of random-start ovarian stimulation in women desiring elective oocyte cryopreservation. Women in the study cohort underwent random-start ovarian stimulation, and were subdivided based on the phase of the menstrual cycle that ovarian stimulation began, i.e. early follicular, late follicular or luteal phase. Women undergoing conventional cycle day (CD) 2/3 ovarian stimulation start were controls. A total of 1302 women were included - 859 (66.0%) conventional CD 2/3, 342 (26.3%) early follicular, 42 (3.2%) late follicular and 59 (4.5%) luteal ovarian stimulation starts. There was no difference in the demographics or baseline ovarian stimulation characteristics. The duration of ovarian stimulation (11 versus 9 days; P start group. The number of total and MII oocytes in the control and random-start groups was similar. A non-significant trend towards increased cycle cancellation was noted in the late follicular start group (7.1%). Study findings indicate the number of total and MII oocytes derived from random-start protocols initiated during any phase of the menstrual cycle is similar to conventional CD 2/3 ovarian stimulation start protocols in women desiring elective oocyte cryopreservation. Copyright © 2017 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

  20. Start-up assist by magnetized plasma flow injection in TPE-RX reversed-field pinch

    Energy Technology Data Exchange (ETDEWEB)

    Asai, T. [College of Science and Technology, Nihon University, 1-8 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8308 (Japan)]. E-mail: asai@phys.cst.nihon-u.ac.jp; Nagata, M. [Graduate School of Engineering, University of Hyogo, Himeji (Japan); Koguchi, H. [National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba (Japan); Hirano, Y. [National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba (Japan); Sakakita, H. [National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba (Japan); Yambe, K. [National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba (Japan); Kiyama, S. [National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba (Japan)

    2006-11-15

    A reversed-field pinch (RFP) start-up assisted by a magnetized plasma flow injection was demonstrated for the first time on a TPE-RX machine. This sequence of experiments aimed to establish a new method of ionization, gas-fill and helicity injection in the start-up phase of an RFP. In this start-up method, magnetized and well-ionized plasma is formed by a magnetized coaxial plasma gun and injected into the torus chamber as an initial pre-ionized plasma for RFP formation. In the initial experiments, attenuated density pump-out and comparatively slow decay of the toroidal flux and plasma current were observed as evidence of its being an effective start-up method.

  1. Influence of Homogenization and Micro/Nano Source of Starting Powders on Format Ion of the Single YAP Phase

    Directory of Open Access Journals (Sweden)

    Michalik D.

    2016-12-01

    Full Text Available Manufacturing high purity polycrystalline YAlO3 (YAP ceramics could replace monocrystalline YAP thus recently it is an interesting task for low cost producers of scintillators. The paper presents influence of different source of initial oxide powders (micro/nano powders of Y2O3 and Al2O3 and the method of their homogenization on the formation of a YAP phase. The solid state reaction method was used to prepare YAP powder or ceramic pellets. After preheating, all samples in the form of powders and pellets were heat-treated in the temperature range of 1050-1650 °C. DTA method was applied for examination of the phase crystallization in the tested system. X-ray diffraction method (XRD was used for characterization of the phase composition. X-ray microanalysis (EDS was used to control homogeneity in the small areas. Morphology of the resultant samples are presented on SEM pictures. The results show a significant influence of the starting powders on the homogeneity, purity and temperature of formation of the main phase.

  2. Technological start of T-15 tokamak. The start-up diagnostic complex

    International Nuclear Information System (INIS)

    Notkin, G.E.

    1989-01-01

    The T-15 tokamak with superconducting toroidal winding reached the technological start-up phase. The results of the first operating tests of the main tokamak components are reported. Due to improper function of both the vacuum and the cryogenic system, the nominal parameters of the vacuum and of the toroidal magnetic field have not been achieved. The non-optimum vacuum conditions made the discharge start-up difficult even when a pre-ionizing electron beam and a gyrotron generator were used. The pre-discharge plasma parametes were studied by means of a limited set of plasma diagnostic apparatus. Due to substantially deteriorated vacuum conditions, it was not possible to repeat the only one successful discharge with a current of 100 kA, lasting for 50 ms. (J.U.)

  3. Dead-Time Generation in Six-Phase Frequency Inverter

    Directory of Open Access Journals (Sweden)

    Aurelijus Pitrėnas

    2016-06-01

    Full Text Available In this paper control of multi-phase induction drives is discussed. Structure of six-phase frequency inverter is examined. The article deals with dead-time generation circuits in six-phase frequency inverter for transistor control signals. Computer models of dead-time circuits is created using LTspice software package. Simulation results are compared with experimental results of the tested dead-time circuits. Parameters obtained in simulation results are close to the parameters obtained in experimental results.

  4. Comparison of minute distribution frequency for anesthesia start and end times from an anesthesia information management system and paper records.

    Science.gov (United States)

    Phelps, Michael; Latif, Asad; Thomsen, Robert; Slodzinski, Martin; Raghavan, Rahul; Paul, Sharon Leigh; Stonemetz, Jerry

    2017-08-01

    Use of an anesthesia information management system (AIMS) has been reported to improve accuracy of recorded information. We tested the hypothesis that analyzing the distribution of times charted on paper and computerized records could reveal possible rounding errors, and that this effect could be modulated by differences in the user interface for documenting certain event times with an AIMS. We compared the frequency distribution of start and end times for anesthesia cases completed with paper records and an AIMS. Paper anesthesia records had significantly more times ending with "0" and "5" compared to those from the AIMS (p < 0.001). For case start times, AIMS still exhibited end-digit preference, with times whose last digits had significantly higher frequencies of "0" and "5" than other integers. This effect, however, was attenuated compared to that for paper anesthesia records. For case end times, the distribution of minutes recorded with AIMS was almost evenly distributed, unlike those from paper records that still showed significant end-digit preference. The accuracy of anesthesia case start times and case end times, as inferred by statistical analysis of the distribution of the times, is enhanced with the use of an AIMS. Furthermore, the differences in AIMS user interface for documenting case start and case end times likely affects the degree of end-digit preference, and likely accuracy, of those times.

  5. Late-time cosmological phase transitions

    International Nuclear Information System (INIS)

    Schramm, D.N.

    1990-11-01

    It is shown that the potential galaxy formation and large-scale structure problems of objects existing at high redshifts (Z approx-gt 5), structures existing on scales of 100M pc as well as velocity flows on such scales, and minimal microwave anisotropies (ΔT/T) approx-lt 10 -5 can be solved if the seeds needed to generate structure form in a vacuum phase transition after decoupling. It is argued that the basic physics of such a phase transition is no more exotic than that utilized in the more traditional GUT scale phase transitions, and that, just as in the GUT case, significant random gaussian fluctuations and/or topological defects can form. Scale lengths of ∼100M pc for large-scale structure as well as ∼1 M pc for galaxy formation occur naturally. Possible support for new physics that might be associated with such a late-time transition comes from the preliminary results of the SAGE solar neutrino experiment, implying neutrino flavor mixing with values similar to those required for a late-time transition. It is also noted that a see-saw model for the neutrino masses might also imply a tau neutrino mass that is an ideal hot dark matter candidate. However, in general either hot or cold dark matter can be consistent with a late-time transition. 47 refs., 2 figs

  6. Control of photon storage time using phase locking.

    Science.gov (United States)

    Ham, Byoung S

    2010-01-18

    A photon echo storage-time extension protocol is presented by using a phase locking method in a three-level backward propagation scheme, where phase locking serves as a conditional stopper of the rephasing process in conventional two-pulse photon echoes. The backward propagation scheme solves the critical problems of extremely low retrieval efficiency and pi rephasing pulse-caused spontaneous emission noise in photon echo based quantum memories. The physics of the storage time extension lies in the imminent population transfer from the excited state to an auxiliary spin state by a phase locking control pulse. We numerically demonstrate that the storage time is lengthened by spin dephasing time.

  7. Why START?

    International Nuclear Information System (INIS)

    Mendelsohn, J.

    1991-01-01

    Barring some major unexpected downturn in US-Soviet relations, it seems likely that the long-awaited Strategic Arms Reduction Talks (START) treaty will be signed sometime in 1991. Under negotiation for the past nine years, public acceptance and Senate approval of a START treaty will be facilitated by the generally less confrontational East-West relationship which has evolved over that time, by the growing constraints on the US defense budget, and by the obvious merits of the treaty itself. Not only will the nearly complete START treaty be an extremely useful and powerful arms control agreement, it is also decidedly advantageous to US security interests. First and foremost, a START treaty will cap and reduce the steady buildup of nuclear weapons that has characterized the last 30 years of the US-Soviet strategic relationship. As a result of the basic outline originally agreed to at the Reykjavik summit, START will take a 25 to 35 percent bite out of existing nuclear arsenals, impose approximately a 50 percent cut in overall Soviet ballistic missile warheads and throw-weight (lifting power or payload capacity), and produce an exact 50 percent cut in Soviet SS-18 missiles

  8. Phase correlation and clustering of a nearest neighbour coupled oscillators system

    CERN Document Server

    Ei-Nashar, H F

    2002-01-01

    We investigated the phases in a system of nearest neighbour coupled oscillators before complete synchronization in frequency occurs. We found that when oscillators under the influence of coupling form a cluster of the same time-average frequency, their phases start to correlate. An order parameter, which measures this correlation, starts to grow at this stage until it reaches maximum. This means that a time-average phase locked state is reached between the oscillators inside the cluster of the same time- average frequency. At this strength the cluster attracts individual oscillators or a cluster to join in. We also observe that clustering in averaged frequencies orders the phases of the oscillators. This behavior is found at all the transition points studied.

  9. Phase correlation and clustering of a nearest neighbour coupled oscillators system

    International Nuclear Information System (INIS)

    EI-Nashar, Hassan F.

    2002-09-01

    We investigated the phases in a system of nearest neighbour coupled oscillators before complete synchronization in frequency occurs. We found that when oscillators under the influence of coupling form a cluster of the same time-average frequency, their phases start to correlate. An order parameter, which measures this correlation, starts to grow at this stage until it reaches maximum. This means that a time-average phase locked state is reached between the oscillators inside the cluster of the same time- average frequency. At this strength the cluster attracts individual oscillators or a cluster to join in. We also observe that clustering in averaged frequencies orders the phases of the oscillators. This behavior is found at all the transition points studied. (author)

  10. Crystal phase evolution of TiO2 nanoparticles with reaction time in acidic solutions studied via freeze-drying method

    International Nuclear Information System (INIS)

    Shin, Hyunho; Jung, Hyun Suk; Hong, Kug Sun; Lee, Jung-Kun

    2005-01-01

    The crystal phase evolution of TiO 2 nanoparticles, during hydrolysis and condensation of titanium tetraisopropoxide, was quenched at various reaction times by a freeze-drying method, followed by various characterizations. Three types of solutions with different acid input times were studied: (1) addition in infinite time (no addition) (2) addition at 24h after the hydrolysis/condensation reaction started, and (3) addition from the beginning of the reaction. The acid-free solution yielded amorphous TiO 2 , which transformed to anatase very slowly. The acid input in 24h resulted in a fast transformation of amorphous to a metastable anatase having a highly distorted atomic arrangement: thereby its transformation to a more stable phase, rutile, was suitable. The acid addition from the beginning of the reaction yielded the formation of a relatively stable anatase from the hydrolysis seed, thereby the subsequent transformation to rutile was sluggish

  11. High School Start Times and the Impact on High School Students: What We Know, and What We Hope to Learn

    Science.gov (United States)

    Morgenthaler, Timothy I.; Hashmi, Sarah; Croft, Janet B.; Dort, Leslie; Heald, Jonathan L.; Mullington, Janet

    2016-01-01

    Study Objectives: Several organizations have provided recommendations to ensure high school starts no sooner than 08:30. However, although there are plausible biological reasons to support such recommendations, published recommendations have been based largely on expert opinion and a few observational studies. We sought to perform a critical review of published evidence regarding the effect of high school start times on sleep and other relevant outcomes. Methods: We performed a broad literature search to identify 287 candidate publications for inclusion in our review, which focused on studies offering direct comparison of sleep time, academic or physical performance, behavioral health measures, or motor vehicular accidents in high school students. Where possible, outcomes were combined for meta-analysis. Results: After application of study criteria, only 18 studies were suitable for review. Eight studies were amenable to meta-analysis for some outcomes. We found that later school start times, particularly when compared with start times more than 60 min earlier, are associated with longer weekday sleep durations, lower weekday-weekend sleep duration differences, reduced vehicular accident rates, and reduced subjective daytime sleepiness. Improvement in academic performance and behavioral issues is less established. Conclusions: The literature regarding effect of school start time delays on important aspects of high school life suggests some salutary effects, but often the evidence is indirect, imprecise, or derived from cohorts of convenience, making the overall quality of evidence weak or very weak. This review highlights a need for higher-quality data upon which to base important and complex public health decisions. Citation: Morgenthaler TI, Hashmi S, Croft JB, Dort L, Heald JL, Mullington J. High school start times and the impact on high school students: what we know, and what we hope to learn. J Clin Sleep Med 2016;12(12):1681–1689. PMID:27855730

  12. School Start Times, Sleep, Behavioral, Health, and Academic Outcomes: A Review of the Literature

    Science.gov (United States)

    Wheaton, Anne G.; Chapman, Daniel P.; Croft, Janet B.

    2016-01-01

    Background: Insufficient sleep in adolescents has been shown to be associated with a wide variety of adverse outcomes, from poor mental and physical health to behavioral problems and lower academic grades. However, most high school students do not get sufficient sleep. Delaying school start times for adolescents has been proposed as a policy…

  13. Face to phase: pitfalls in time delay estimation from coherency phase

    NARCIS (Netherlands)

    Campfens, S.F.; van der Kooij, Herman; Schouten, Alfred Christiaan

    2014-01-01

    Coherency phase is often interpreted as a time delay reflecting a transmission delay between spatially separated neural populations. However, time delays estimated from corticomuscular coherency are conflicting and often shorter than expected physiologically. Recent work suggests that

  14. On the measurement of time-dependent quantum phases

    International Nuclear Information System (INIS)

    Barut, A.O.; Bozic, M.; Klarsfeld, S.; Maric, Z.

    1991-11-01

    We have evaluated the exact (Pancharatnam) phase differences between the final state l ψ(t) > and various initial states for a spin 1/2-particle in a rotating magnetic field B(t). For the initial states l n; B ef (0) >, which are eigenstates of the spin component along the direction of the initial effective field B ef (0), the exact phase has an energy dependent part, and an energy independent part. It is shown that these states l n; B ef (0) > are cyclic and their corresponding Aharonov-Anandan phases are evaluated. In the adiabatic limit we discuss different choices of time-dependent bases and the relationship between the exact phase, the Born-Fock-Schiff phase and Berry's phase. We propose experiments (neutron) to verify separately the exact and the adiabatic evolution laws, as well as to measure the adiabatic phases associated with different choices of time-dependent basis vectors. (author). 37 refs, 5 figs, 1 tab

  15. Start-up phase of a two-stage anaerobic co-digestion process: Hydrogen and methane production from food waste and vinasse from ethanol industry

    DEFF Research Database (Denmark)

    Náthia-Neves, Grazielle; Neves, Thiago de Alencar; Berni, Mauro

    2018-01-01

    The start-up conditions of mesophilic anaerobic co-digestion of restaurant food waste and vinasse, a waste from sugarcane industry, was investigated for efficient biogas production. A pilot plant, containing two reactors, was designed and used sequentially and semi-continuously for biogas...... production. All effective operational parameters were controlled in both reactors over the course of the study. The results indicated that the organic matters were quickly decreased during the start-up phase in the first reactor, resulting in 52% and 64% reduction in total solids and total volatile solids...

  16. The impact of dry-land sprint start training on the short track speed skating start.

    Science.gov (United States)

    Haug, William B; Drinkwater, Eric J; Cicero, Nicholas J; Barthell, J Anthony; Chapman, Dale W

    2017-05-05

    This investigation sought to determine the effects of dry-land sprint start training on short track speed skating (STSS) start performance. Nine highly trained short track athletes completed a control period of normal STSS training followed by a four-week training intervention. Before and after the control and intervention periods, athletes performed three electronically timed dry-land and on-ice 14.43 m maximal sprint start efforts. The intervention consisted of two sprint sessions per week consisting of nine electronically timed 14.43 m dry-land sprint starts in addition to normal STSS training. The control period resulted in no substantial change in on-ice start performance (Mean Δ: -0.01 s, 95% Confidence Limits (CL): -0.08 to 0.05 s; Effect Size (ES): -0.05; Trivial) however, a small change was observed in dry-land start performance (Mean Δ: -0.07 s, 95% CL: -0.13 to -0.02 s; ES: -0.49). Following brief specific dry-land sprint start training a small improvement was observed in both on-ice (Mean Δ: -0.07 s, 95% CL: -0.13 to -0.01 s; ES: -0.33) and dry-land (Mean Δ: -0.04 s, 95% CL: -0.09 to 0.00 s; ES: -0.29) start performance. This investigation suggests STSS start performance can be improved through a brief dry-land sprint start training program.

  17. Preliminary time-phased TWRS process model results

    International Nuclear Information System (INIS)

    Orme, R.M.

    1995-01-01

    This report documents the first phase of efforts to model the retrieval and processing of Hanford tank waste within the constraints of an assumed tank farm configuration. This time-phased approach simulates a first try at a retrieval sequence, the batching of waste through retrieval facilities, the batching of retrieved waste through enhanced sludge washing, the batching of liquids through pretreatment and low-level waste (LLW) vitrification, and the batching of pretreated solids through high-level waste (HLW) vitrification. The results reflect the outcome of an assumed retrieval sequence that has not been tailored with respect to accepted measures of performance. The batch data, composition variability, and final waste volume projects in this report should be regarded as tentative. Nevertheless, the results provide interesting insights into time-phased processing of the tank waste. Inspection of the composition variability, for example, suggests modifications to the retrieval sequence that will further improve the uniformity of feed to the vitrification facilities. This model will be a valuable tool for evaluating suggested retrieval sequences and establishing a time-phased processing baseline. An official recommendation on tank retrieval sequence will be made in September, 1995

  18. Experimental investigation of the ECRH stray radiation during the start-up phase in Wendelstein 7-X

    Science.gov (United States)

    Moseev, Dmitry; Laqua, Heinrich; Marsen, Stefan; Stange, Torsten; Braune, Harald; Erckmann, Volker; Gellert, Florian; Oosterbeek, Johann Wilhelm; Wenzel, Uwe

    2017-07-01

    Electron cyclotron resonance heating (ECRH) is the main heating mechanism in the Wendelstein 7-X stellarator (W7-X). W7-X is equipped with five absolutely calibrated sniffer probes that are installed in each of the five modules of the device. The sniffer probes monitor energy flux of unabsorbed ECRH radiation in the device and interlocks are fed with the sniffer probe signals. The stray radiation level in the device changes significantly during the start-up phase: plasma is a strong microwave absorber and during its formation the stray radiation level in sniffer probes reduces by more than 95%. In this paper, we discuss the influence of neutral gas pressure and gyrotron power on plasma breakdown processes.

  19. Application of artificial neural network to predict the optimal start time for heating system in building

    International Nuclear Information System (INIS)

    Yang, In-Ho; Yeo, Myoung-Souk; Kim, Kwang-Woo

    2003-01-01

    The artificial neural network (ANN) approach is a generic technique for mapping non-linear relationships between inputs and outputs without knowing the details of these relationships. This paper presents an application of the ANN in a building control system. The objective of this study is to develop an optimized ANN model to determine the optimal start time for a heating system in a building. For this, programs for predicting the room air temperature and the learning of the ANN model based on back propagation learning were developed, and learning data for various building conditions were collected through program simulation for predicting the room air temperature using systems of experimental design. Then, the optimized ANN model was presented through learning of the ANN, and its performance to determine the optimal start time was evaluated

  20. A novel start-up procedure for natural-circulation boiling water reactors

    International Nuclear Information System (INIS)

    Annalisa Manera; Frank Schaefer

    2005-01-01

    Valves). In this case steam is generated due to flashing at high pressure. The simulation by means of TRACG shows that no flow oscillations occur during the transition from single- to two-phase operation. A similar start-up procedure is simulated by Cheng and coauthors [4] by means of the code RAMONA-4B. They find contradicting results compared to the one obtained by Cheung and Rao. However, RAMONA-4B cannot predict the occurrence of flashing at low pressures, since a single average system pressure is used by this code to calculate thermodynamic properties of water and steam in the system. Therefore, the results obtained by this code are meaningless with regard to the start-up of natural circulation two-phase systems. In the present work a novel start-up procedure will be illustrated which does not require any additional system and in which there is no necessity for an abrupt steam production at high pressure [5], as in the procedure of Cheung and Rao. In the procedure proposed in this work, the reactor vessel is pressurized by means of steam produced in the reactor vessel itself, but outside the core and riser section. In this way, the system can be pressurized while the reactor still operates in single-phase conditions, thus without occurrence of flashing-induced flow oscillations. At the same time, a smooth steam production and pressurization of the system is achieved. The feasibility of the intermediate state in which steam is produced in the reactor vessel while the circulation in core and riser sections remains single-phase has been already proved during an experimental campaign performed at the large-scale facility PANDA. The procedure is simulated by means of the ATHLET code, developed by GRS (Germany). This code has been successfully qualified against low-pressure flashing-induced instabilities within the framework of the EU project NACUSP. (authors)

  1. STARTing Again: What Happens After START I Expires?

    International Nuclear Information System (INIS)

    Mladineo, Stephen V.; Durbin, Karyn R.; Eastman, Christina M.

    2007-01-01

    The Strategic Arms Reduction Treaty (START I), a seminal arms control agreement that substantially reduced the levels of deployed strategic nuclear arms in the United States and Russia, will expire in December 2009. At this time, it is unclear what - if anything - will replace it. While the treaty remains relevant, more than a simple extension is appropriate. Instead the authors advocate for a successor regime that builds on the START I legacy but does not rely on the traditional tools of arms control. This paper examines the strategic context in which a successor regime would be developed and proposes several recommendations for future action

  2. Strategies for the optimal timing to start renal replacement therapy in critically ill patients with acute kidney injury.

    Science.gov (United States)

    Bagshaw, Sean M; Wald, Ron

    2017-05-01

    Renal replacement therapy (RRT) is increasingly utilized to support critically ill patients with severe acute kidney injury (AKI). The question of whether and when to start RRT for a critically ill patient with AKI has long troubled clinicians. When severe complications of AKI develop, the need to commence RRT is unambiguous. In the absence of such complications but in the presence of severe AKI, the optimal time and thresholds for starting RRT are uncertain. The majority of existing data have largely been derived from observational studies. These have been limited due to confounding by indication, considerable heterogeneity in case mix and illness severity, and variably applied definitions for both AKI and for how "timing" was anchored relative to starting RRT. It is unclear whether a preemptive or earlier strategy of RRT initiation aimed largely at avoiding complications related to AKI or a more conservative strategy where RRT is started in response to developing complications leads to better patient-centered outcomes and health services use. This question has been the focus of 2 recently completed randomized trials. In this review, we provide an appraisal of available evidence, discuss existing knowledge gaps, and provide perspective on future research that will better inform the optimal timing of RRT initiation in AKI. Copyright © 2016 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

  3. High School Start Times and the Impact on High School Students: What We Know, and What We Hope to Learn.

    Science.gov (United States)

    Morgenthaler, Timothy I; Hashmi, Sarah; Croft, Janet B; Dort, Leslie; Heald, Jonathan L; Mullington, Janet

    2016-12-15

    Several organizations have provided recommendations to ensure high school starts no sooner than 08:30. However, although there are plausible biological reasons to support such recommendations, published recommendations have been based largely on expert opinion and a few observational studies. We sought to perform a critical review of published evidence regarding the effect of high school start times on sleep and other relevant outcomes. We performed a broad literature search to identify 287 candidate publications for inclusion in our review, which focused on studies offering direct comparison of sleep time, academic or physical performance, behavioral health measures, or motor vehicular accidents in high school students. Where possible, outcomes were combined for meta-analysis. After application of study criteria, only 18 studies were suitable for review. Eight studies were amenable to meta-analysis for some outcomes. We found that later school start times, particularly when compared with start times more than 60 min earlier, are associated with longer weekday sleep durations, lower weekday-weekend sleep duration differences, reduced vehicular accident rates, and reduced subjective daytime sleepiness. Improvement in academic performance and behavioral issues is less established. The literature regarding effect of school start time delays on important aspects of high school life suggests some salutary effects, but often the evidence is indirect, imprecise, or derived from cohorts of convenience, making the overall quality of evidence weak or very weak. This review highlights a need for higher-quality data upon which to base important and complex public health decisions. © 2016 American Academy of Sleep Medicine

  4. Radiation therapy of Graves' ophthalmopathy. 2; Therapy started time

    Energy Technology Data Exchange (ETDEWEB)

    Kawamura, Toshinori; Koga, Sukehiko (Fujita Health Univ., Toyoake, Aichi (Japan). School of Medicine)

    1994-04-01

    The difference in the improvement of exophthalmos according to the period of starting radiation therapy was investigated for 26 patients of thyroid ophthalmopathy, also taking thyroidism during radiation into consideration. A 4 MV X-ray was used to a total dose of 20 Gy per 2 weeks. The treatment value tended to be better for the patients in whom the period from the appearance of exophthalmos in an euthyroid condition to the start of radiation was less than 12 months; those of a longer period showed poorer improvement. Radiation treatment of a hyperthyroid condition also showed poor results and it was thought it was not an adequately long enough period for the radiation to take effect. As a result, it was considered that the radiation therapy shall be advantageous if started within 12 months after the appearance of exophthalmos in an euthyroid condition. (author).

  5. Phase correlation of foreign exchange time series

    Science.gov (United States)

    Wu, Ming-Chya

    2007-03-01

    Correlation of foreign exchange rates in currency markets is investigated based on the empirical data of USD/DEM and USD/JPY exchange rates for a period from February 1 1986 to December 31 1996. The return of exchange time series is first decomposed into a number of intrinsic mode functions (IMFs) by the empirical mode decomposition method. The instantaneous phases of the resultant IMFs calculated by the Hilbert transform are then used to characterize the behaviors of pricing transmissions, and the correlation is probed by measuring the phase differences between two IMFs in the same order. From the distribution of phase differences, our results show explicitly that the correlations are stronger in daily time scale than in longer time scales. The demonstration for the correlations in periods of 1986-1989 and 1990-1993 indicates two exchange rates in the former period were more correlated than in the latter period. The result is consistent with the observations from the cross-correlation calculation.

  6. Start up testing for the secure automated fabrication line

    International Nuclear Information System (INIS)

    Gerber, E.W.; Benson, E.M.; Dahl, R.E.

    1987-01-01

    The secure automated fabrication (SAF) line is a remotely operated, liquid metal reactor fuel fabrication process being built by Westinghouse Hanford Company for the Department of Energy. All process and control equipment is installed and start up testing has been initiated. Start up testing is comprised of five phases, each incorporating higher degrees of equipment integration, automation, and remote control. Testing methodology for SAF line start up is described in this report

  7. Frequency-domain waveform inversion using the phase derivative

    KAUST Repository

    Choi, Yun Seok; Alkhalifah, Tariq Ali

    2013-01-01

    Phase wrapping in the frequency domain or cycle skipping in the time domain is the major cause of the local minima problem in the waveform inversion when the starting model is far from the true model. Since the phase derivative does not suffer from

  8. A Bayesian Approach to Real-Time Earthquake Phase Association

    Science.gov (United States)

    Benz, H.; Johnson, C. E.; Earle, P. S.; Patton, J. M.

    2014-12-01

    Real-time location of seismic events requires a robust and extremely efficient means of associating and identifying seismic phases with hypothetical sources. An association algorithm converts a series of phase arrival times into a catalog of earthquake hypocenters. The classical approach based on time-space stacking of the locus of possible hypocenters for each phase arrival using the principal of acoustic reciprocity has been in use now for many years. One of the most significant problems that has emerged over time with this approach is related to the extreme variations in seismic station density throughout the global seismic network. To address this problem we have developed a novel, Bayesian association algorithm, which looks at the association problem as a dynamically evolving complex system of "many to many relationships". While the end result must be an array of one to many relations (one earthquake, many phases), during the association process the situation is quite different. Both the evolving possible hypocenters and the relationships between phases and all nascent hypocenters is many to many (many earthquakes, many phases). The computational framework we are using to address this is a responsive, NoSQL graph database where the earthquake-phase associations are represented as intersecting Bayesian Learning Networks. The approach directly addresses the network inhomogeneity issue while at the same time allowing the inclusion of other kinds of data (e.g., seismic beams, station noise characteristics, priors on estimated location of the seismic source) by representing the locus of intersecting hypothetical loci for a given datum as joint probability density functions.

  9. Time-dependent phase error correction using digital waveform synthesis

    Science.gov (United States)

    Doerry, Armin W.; Buskirk, Stephen

    2017-10-10

    The various technologies presented herein relate to correcting a time-dependent phase error generated as part of the formation of a radar waveform. A waveform can be pre-distorted to facilitate correction of an error induced into the waveform by a downstream operation/component in a radar system. For example, amplifier power droop effect can engender a time-dependent phase error in a waveform as part of a radar signal generating operation. The error can be quantified and an according complimentary distortion can be applied to the waveform to facilitate negation of the error during the subsequent processing of the waveform. A time domain correction can be applied by a phase error correction look up table incorporated into a waveform phase generator.

  10. Late time phase transition as dark energy

    Indian Academy of Sciences (India)

    Abstract. We show that the dark energy field can naturally be described by the scalar condensates of a non-abelian gauge group. This gauge group is unified with the standard model gauge groups and it has a late time phase transition. The small phase transition explains why the positive acceleration of the universe is ...

  11. Relationship between the start times of flares and CMEs to the time of potential radiation hazards

    Science.gov (United States)

    Kang, G.; Zheng, Y.; Kuznetsova, M. M.

    2013-12-01

    Solar flares, short-term outbursts of energy of the Sun, and coronal mass ejections (CME), massive bursts of solar matter, are two solar phenomena that are known to increase solar energetic particles in space. Increased solar energetic particles cause immense radiation that poses a serious threat to astronauts in space, radio communication signals, and passengers on high-latitude flights on the Earth. The relationship between the start times of flares and CMEs to the time of potential radiation hazards was investigated to determine how much warning time is available. Additionally, this project compared the difference between these relationships for four energy levels of solar energetic particles: proton flux exceeding 10 MeV, 30 MeV, 50 MeV and 100 MeV. This project gathered data of 22 recent SEP events between 2010 and 2012 and the parameters of associated CMEs and flares. Through the use of IDL (Interactive Data Language) programming, thorough analysis was conducted, including 2-sample t-tests and Kruskal-Wallis tests for 2 or more samples. The average lead time to warn humans of possible radiation hazard from the detection of a flare and a CME occurrence was found to be around 12 to 20 hours. The lead time was the greatest for the lowest energy level, though the differences in energy levels and that between the lead times for CME and flares were found to be statistically insignificant with p-values exceeding the alpha value of 0.20.

  12. Evaluation of hearing ability in Danish children at the time of school start and at the end of school

    DEFF Research Database (Denmark)

    Gissel, S.; Mortensen, Jens Tølbøll; Juul, S.

    2002-01-01

    Since previous studies have shown reduced hearing ability in children and adolescents at school start, this study was undertaken to evaluate the hearing ability in Danish children at the time of start and end of school. Children starting school in 1977, 1987, and 1997 from four minor municipalities....... At the end of school, hearing ability of the year group 1977 was just as poor as for the year group 1987. Whether reduced hearing can influence the learning abilities of these children should be evaluated by further studies including information on the exposure to noise....

  13. Preparation phase of Mochovce NPP unit 3 and 4 construction completion

    International Nuclear Information System (INIS)

    Cillik, I.; Tvaroska, V.; Liska, P.; Ziman, V.

    2005-01-01

    In this presentation authors deal with preparation phase of Mochovce NPP unit 3 and 4 construction completion. The preparation phase of the Mochovce unit 3 and 4 construction completion gives following main outputs: (a) Detail Safety Concept gives definitive complex safety and technical improvement of MO34, more precise analysis of the total cost of construction completion, a list of potential suppliers and construction completion time schedule; (b) Appendices of Basic Design Documentation and Preliminary SAR serves as basic documentation for UJD SR decision making according to Law No. 541 for start of Realization Phase; (c) The Preparation Phase represents effective tool for start of MO34 construction completion Realization Phase.

  14. An impressive start

    CERN Multimedia

    2011-01-01

    This has been an excellent week for the LHC, with a succession of fills rapidly increasing the number of proton bunches to 194 per beam. This has allowed the experiments to reach a peak luminosity of 2.5 × 1032 cm-2s-1, thereby surpassing the record for 2010 where we reached 2.0 × 1032 cm-2s-1. At the time of writing, the integrated luminosity delivered by the LHC in 2011 is around 28 inverse picobarns, which is already more than half of the total 2010 dataset.   These are impressive numbers, but what impresses me most is how quickly the LHC operators are now able to turn the machine around between fills, and how well LHC running has been incorporated into the overall operation of CERN’s accelerator complex. The flexibility of the LHC was illustrated on Thursday when we started a short phase of running at 1.38 TeV per beam, equivalent to the energy-per-nucleon of a lead-ion run. This lower energy data will be used by the experiments, in particular by ALICE, to compare...

  15. The influence of gate start position on physical performance and anxiety perception in expert BMX athletes.

    Science.gov (United States)

    Di Rienzo, Franck; Martinent, Guillaume; Levêque, Lucie; MacIntyre, Tadhg; Collet, Christian; Guillot, Aymeric

    2018-02-01

    The critical importance of the start phase in bicycle motocross (BMX) racing is increasingly acknowledged. Past experiments underlined that the internal lane of the starting gate provides a strong positional advantage. However, how lane position affects start performance and cognitive and somatic state anxiety remains unexplored. We examined the start performance and anxiety responses of youth national-level BMX riders in both experimental and ecological contexts. We used contextualization motor imagery routines to evaluate start performance and state anxiety from the internal and external lanes. Cycle ergometer measures revealed a better start performance from the external lane, but we did not record any lane effect on actual gate start times. Both somatic and cognitive anxiety scores were higher before racing from the internal compared to the external lane. Finally, state anxiety (i.e., somatic anxiety, worry and concentration disruptions) negatively predicted the start performance. Present findings provide original insights on psychological factors involved in BMX start performance, and might contribute to fruitful coping interventions and training programmes in sports overlapping the framework of "handicap races" taking the specific form of positional advantages/disadvantages at the start (e.g., ski/snowboard cross, athletics, swimming, motorsports, etc.).

  16. Evaluation of hearing ability in Danish children at the time of school start and at the end of school

    DEFF Research Database (Denmark)

    Gissel, S.; Mortensen, Jens Tølbøll; Juul, S.

    2002-01-01

    Since previous studies have shown reduced hearing ability in children and adolescents at school start, this study was undertaken to evaluate the hearing ability in Danish children at the time of start and end of school. Children starting school in 1977, 1987, and 1997 from four minor municipalities...... in North Jutland County, Denmark were evaluated for hearing ability by a review of 1,605 school health records. We found a higher prevalence of impaired hearing ability in children who started school 1987 and 1997 compared to those who started school 1977. Reduced hearing was typically at high frequencies....... At the end of school, hearing ability of the year group 1977 was just as poor as for the year group 1987. Whether reduced hearing can influence the learning abilities of these children should be evaluated by further studies including information on the exposure to noise....

  17. A longitudinal assessment of sleep timing, circadian phase, and phase angle of entrainment across human adolescence.

    Directory of Open Access Journals (Sweden)

    Stephanie J Crowley

    Full Text Available The aim of this descriptive analysis was to examine sleep timing, circadian phase, and phase angle of entrainment across adolescence in a longitudinal study design. Ninety-four adolescents participated; 38 (21 boys were 9-10 years ("younger cohort" and 56 (30 boys were 15-16 years ("older cohort" at the baseline assessment. Participants completed a baseline and then follow-up assessments approximately every six months for 2.5 years. At each assessment, participants wore a wrist actigraph for at least one week at home to measure self-selected sleep timing before salivary dim light melatonin onset (DLMO phase - a marker of the circadian timing system - was measured in the laboratory. Weekday and weekend sleep onset and offset and weekend-weekday differences were derived from actigraphy. Phase angles were the time durations from DLMO to weekday sleep onset and offset times. Each cohort showed later sleep onset (weekend and weekday, later weekend sleep offset, and later DLMO with age. Weekday sleep offset shifted earlier with age in the younger cohort and later in the older cohort after age 17. Weekend-weekday sleep offset differences increased with age in the younger cohort and decreased in the older cohort after age 17. DLMO to sleep offset phase angle narrowed with age in the younger cohort and became broader in the older cohort. The older cohort had a wider sleep onset phase angle compared to the younger cohort; however, an age-related phase angle increase was seen in the younger cohort only. Individual differences were seen in these developmental trajectories. This descriptive study indicated that circadian phase and self-selected sleep delayed across adolescence, though school-day sleep offset advanced until no longer in high school, whereupon offset was later. Phase angle changes are described as an interaction of developmental changes in sleep regulation interacting with psychosocial factors (e.g., bedtime autonomy.

  18. Global profiling of DNA replication timing and efficiency reveals that efficient replication/firing occurs late during S-phase in S. pombe.

    Directory of Open Access Journals (Sweden)

    Majid Eshaghi

    Full Text Available BACKGROUND: During S. pombe S-phase, initiation of DNA replication occurs at multiple sites (origins that are enriched with AT-rich sequences, at various times. Current studies of genome-wide DNA replication profiles have focused on the DNA replication timing and origin location. However, the replication and/or firing efficiency of the individual origins on the genomic scale remain unclear. METHODOLOGY/PRINCIPAL FINDINGS: Using the genome-wide ORF-specific DNA microarray analysis, we show that in S. pombe, individual origins fire with varying efficiencies and at different times during S-phase. The increase in DNA copy number plotted as a function of time is approximated to the near-sigmoidal model, when considering the replication start and end timings at individual loci in cells released from HU-arrest. Replication efficiencies differ from origin to origin, depending on the origin's firing efficiency. We have found that DNA replication is inefficient early in S-phase, due to inefficient firing at origins. Efficient replication occurs later, attributed to efficient but late-firing origins. Furthermore, profiles of replication timing in cds1Delta cells are abnormal, due to the failure in resuming replication at the collapsed forks. The majority of the inefficient origins, but not the efficient ones, are found to fire in cds1Delta cells after HU removal, owing to the firing at the remaining unused (inefficient origins during HU treatment. CONCLUSIONS/SIGNIFICANCE: Taken together, our results indicate that efficient DNA replication/firing occurs late in S-phase progression in cells after HU removal, due to efficient late-firing origins. Additionally, checkpoint kinase Cds1p is required for maintaining the efficient replication/firing late in S-phase. We further propose that efficient late-firing origins are essential for ensuring completion of DNA duplication by the end of S-phase.

  19. Earlier School Start Times as a Risk Factor for Poor School Performance: An Examination of Public Elementary Schools in the Commonwealth of Kentucky

    Science.gov (United States)

    Keller, Peggy S.; Smith, Olivia A.; Gilbert, Lauren R.; Bi, Shuang; Haak, Eric A.; Buckhalt, Joseph A.

    2015-01-01

    Adequate sleep is essential for child learning. However, school systems may inadvertently be promoting sleep deprivation through early school start times. The current study examines the potential implications of early school start times for standardized test scores in public elementary schools in Kentucky. Associations between early school start…

  20. What Happens at the Lesson Start?

    Science.gov (United States)

    Saloviita, Timo

    2016-01-01

    Transitional periods, such as lesson starts, are necessary steps from one activity to another, but they also compete with time for actual learning. The aim of the present study was to replicate a previous pilot study on lesson starts and explore possible disturbances. In total, 130 lesson starts in Finnish basic education in grades 1-9 were…

  1. PERFORMANCE-BASED CONTRACTING IN CONSTRUCTION PHASE AND MAINTENANCE PHASE OF PAVEMENT

    Science.gov (United States)

    Yoshida, Takeshi

    Performance-based contracting for pavement in Japan started as performance warranties in construction phase, in 1999. Recently, road agencies have recognized the applicability of this type of contracting in outsourcing of maintenance activities. The objectives of this study are to clarify the issues of performance specifying in construction phase and maintenance phase of pavement, and to propose measures to be taken. This paper, with the recognition that the life of each pavement depends on performance standards for various attributes, reviews domestic and foreign examples of performance-based contracting. A performance standard based on the average of current practices can enhance product quality and service life with a warranty contract. Repair thresholds and response time for each deficiency should be considered as performance standards in maintenance phase.

  2. Time-dependent weak values and their intrinsic phases of evolution

    International Nuclear Information System (INIS)

    Parks, A D

    2008-01-01

    The equation of motion for a time-dependent weak value of a quantum-mechanical observable is known to contain a complex valued energy factor (the weak energy of evolution) that is defined by the dynamics of the pre-selected and post-selected states which specify the observable's weak value. In this paper, the mechanism responsible for the creation of this energy is identified and it is shown that the cumulative effect over time of this energy is manifested as dynamical phases and pure geometric phases (the intrinsic phases of evolution) which govern the evolution of the weak value during its measurement process. These phases are simply related to a Pancharatnam phase and Fubini-Study metric distance defined by the Hilbert space evolution of the associated pre-selected and post-selected states. A characterization of time-dependent weak value evolution as Pancharatnam phase angle rotations and Fubini-Study distance scalings of a vector in the Argand plane is discussed as an application of this relationship. The theory of weak values is also reviewed and simple 'gedanken experiments' are used to illustrate both the time-independent and the time-dependent versions of the theory. It is noted that the direct experimental observation of the weak energy of evolution would strongly support the time-symmetric paradigm of quantum mechanics and it is suggested that weak value equations of motion represent a new category of nonlocal equations of motion

  3. General anesthesia alters time perception by phase shifting the circadian clock.

    Science.gov (United States)

    Cheeseman, James F; Winnebeck, Eva C; Millar, Craig D; Kirkland, Lisa S; Sleigh, James; Goodwin, Mark; Pawley, Matt D M; Bloch, Guy; Lehmann, Konstantin; Menzel, Randolf; Warman, Guy R

    2012-05-01

    Following general anesthesia, people are often confused about the time of day and experience sleep disruption and fatigue. It has been hypothesized that these symptoms may be caused by general anesthesia affecting the circadian clock. The circadian clock is fundamental to our well-being because it regulates almost all aspects of our daily biochemistry, physiology, and behavior. Here, we investigated the effects of the most common general anesthetic, isoflurane, on time perception and the circadian clock using the honeybee (Apis mellifera) as a model. A 6-h daytime anesthetic systematically altered the time-compensated sun compass orientation of the bees, with a mean anticlockwise shift in vanishing bearing of 87° in the Southern Hemisphere and a clockwise shift in flight direction of 58° in the Northern Hemisphere. Using the same 6-h anesthetic treatment, time-trained bees showed a delay in the start of foraging of 3.3 h, and whole-hive locomotor-activity rhythms were delayed by an average of 4.3 h. We show that these effects are all attributable to a phase delay in the core molecular clockwork. mRNA oscillations of the central clock genes cryptochrome-m and period were delayed by 4.9 and 4.3 h, respectively. However, this effect is dependent on the time of day of administration, as is common for clock effects, and nighttime anesthesia did not shift the clock. Taken together, our results suggest that general anesthesia during the day causes a persistent and marked shift of the clock effectively inducing "jet lag" and causing impaired time perception. Managing this effect in humans is likely to help expedite postoperative recovery.

  4. A Physics-Based Starting Model for Gas Turbine Engines, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of this proposal is to demonstrate the feasibility of producing an integrated starting model for gas turbine engines using a new physics-based...

  5. Zak Phase in Discrete-Time Quantum Walks

    OpenAIRE

    Puentes, G.; Santillán, O.

    2015-01-01

    We report on a simple scheme that may present a non-trivial geometric Zak phase ($\\Phi_{Zak}$) structure, which is based on a discrete-time quantum walk architecture. By detecting the Zak phase difference between two trajectories connecting adjacent Dirac points where the quasi-energy gap closes for opposite values of quasi-momentum ($k$), it is possible to identify geometric invariants. These geometric invariants correspond to $|\\Phi_{Zak}^{+(-)}-\\Phi_{Zak}^{-(+)}|=\\pi$ and $|\\Phi_{Zak}^{+(-...

  6. Time Series Decomposition into Oscillation Components and Phase Estimation.

    Science.gov (United States)

    Matsuda, Takeru; Komaki, Fumiyasu

    2017-02-01

    Many time series are naturally considered as a superposition of several oscillation components. For example, electroencephalogram (EEG) time series include oscillation components such as alpha, beta, and gamma. We propose a method for decomposing time series into such oscillation components using state-space models. Based on the concept of random frequency modulation, gaussian linear state-space models for oscillation components are developed. In this model, the frequency of an oscillator fluctuates by noise. Time series decomposition is accomplished by this model like the Bayesian seasonal adjustment method. Since the model parameters are estimated from data by the empirical Bayes' method, the amplitudes and the frequencies of oscillation components are determined in a data-driven manner. Also, the appropriate number of oscillation components is determined with the Akaike information criterion (AIC). In this way, the proposed method provides a natural decomposition of the given time series into oscillation components. In neuroscience, the phase of neural time series plays an important role in neural information processing. The proposed method can be used to estimate the phase of each oscillation component and has several advantages over a conventional method based on the Hilbert transform. Thus, the proposed method enables an investigation of the phase dynamics of time series. Numerical results show that the proposed method succeeds in extracting intermittent oscillations like ripples and detecting the phase reset phenomena. We apply the proposed method to real data from various fields such as astronomy, ecology, tidology, and neuroscience.

  7. COLD START CHARACTERISTICS STUDY BASED ON REAL TIME NO EMISSIONS IN AN LPG SI ENGINE

    Directory of Open Access Journals (Sweden)

    Yingli Zu

    2010-01-01

    Full Text Available Normally, cylinder pressure was used as a criterion of combustion occurrence, while in some conditions, it may be unreliable when identifying lean mixture combustion. This is particularly important for fuels like liquefied petroleum gas, which has good capacity for lean combustion. In this study, a fast response NO detector, based on the chemiluminescence method, was used to measure real time NO emissions in order to evaluate the technique as a criterion for establishing combustion occurrence. Test results show that real time NO emissions can be used to identify the cylinder combustion and misfire occurrence during engine cranking, and real time NO emissions can be used to understand the combustion and misfire occurrence. Real time NO emissions mostly happened in first several cycles during cold start, and NO emissions increased with the spark timing advancing.

  8. Drug Abuse Prevention Starts with Parents

    Science.gov (United States)

    ... Stages Listen Español Text Size Email Print Share Drug Abuse Prevention Starts with Parents Page Content Article Body ... for a time when drugs may be offered. Drug abuse prevention starts with parents learning how to talk ...

  9. Phase-Type Models of Channel-Holding Times in Cellular Communication Systems

    DEFF Research Database (Denmark)

    Christensen, Thomas Kaare; Nielsen, Bo Friis; Iversen, Villy Bæk

    2004-01-01

    In this paper, we derive the distribution of the channel-holding time when both cell-residence and call-holding times are phase-type distributed. Furthermore, the distribution of the number of handovers, the conditional channel-holding time distributions, and the channel-holding time when cell re...... residence times are correlated are derived. All distributions are of phase type, making them very general and flexible. The channel-holding times are of importance in performance evaluation and simulation of cellular mobile communication systems.......In this paper, we derive the distribution of the channel-holding time when both cell-residence and call-holding times are phase-type distributed. Furthermore, the distribution of the number of handovers, the conditional channel-holding time distributions, and the channel-holding time when cell...

  10. Start-up of the ohmic phase in JET

    International Nuclear Information System (INIS)

    Tanga, A.; Christiansen, J.P.; Cordey, J.G.; Ejima, S.; Kellman, A.; Lazzaro, E.; Lomas, P.J.; Thomas, P.R.

    1985-01-01

    JET has been designed to permit the study of plasmas in which alphaparticle heating is a significant part of the power balance. In order to have a sufficient thermonuclear yield and to trap the resulting alphaparticles, JET is similar in its dimensions and plasma current to the next generation of reactor-like devices such as NET, FER and INTOR. For this reason, the authors see the results from the study of the start-up of ohmically heated plasmas in JET as highly relevant. Discussed is the range that has been achieved in all major parameters with ohmic heating. Experiences with the wall conditioning technique and the results of ion cyclotron heating experiments in JET are outlined. This paper also describes the stages of plasma formation, current rise and ohmic flat-top

  11. Engine cold start analysis using naturalistic driving data: City level impacts on local pollutants emissions and energy consumption.

    Science.gov (United States)

    Faria, Marta V; Varella, Roberto A; Duarte, Gonçalo O; Farias, Tiago L; Baptista, Patrícia C

    2018-07-15

    The analysis of vehicle cold start emissions has become an issue of utmost importance since the cold phase occurs mainly in urban context, where most of the population lives. In this sense, this research work analyzes and quantifies the impacts of cold start in urban context using naturalistic driving data. Furthermore, an assessment of the influence of ambient temperature on the percentage of time spent on cold start was also performed. Regarding the impacts of ambient temperature on cold start duration, a higher percentage of time spent on cold start was found for lower ambient temperatures (80% of the time for 0°C and ~50% for 29°C). Results showed that, during cold start, energy consumption is >110% higher than during hot conditions while emissions are up to 910% higher. Moreover, a higher increase on both energy consumption and emissions was found for gasoline vehicles than for diesel vehicles. When assessing the impacts on a city perspective, results revealed that the impacts of cold start increase for more local streets. The main finding of this study is to provide evidence that a higher increase on emissions occurs on more local streets, where most of the population lives. This kind of knowledge is of particular relevance to urban planners in order to perform an informed definition of public policies and regulations to be implemented in the future, to achieve a cleaner and healthier urban environment. Copyright © 2018 Elsevier B.V. All rights reserved.

  12. Time since start of first-line therapy as a predictive clinical marker for nintedanib in patients with previously treated non-small cell lung cancer

    DEFF Research Database (Denmark)

    Gaschler-Markefski, Birgit; Sikken, Patricia; Heymach, John V

    2017-01-01

    INTRODUCTION: No predictive clinical or genetic markers have been identified or validated for antiangiogenic agents in lung cancer. We aimed to identify a predictive clinical marker of benefit for nintedanib, an angiokinase inhibitor, using data from two large second-line non-small cell lung cancer...... Phase III trials (LUME-Lung 1 ([LL1] and LUME-Lung 2). METHODS: Predictive marker identification was conducted in a multi-step process using data from both trials; a hypothesis was generated, confirmed and validated. Statistical analyses included a stepwise selection approach, a recursive partitioning...... method and the evaluation of HRs, including treatment-by-covariate interactions. The marker was finally validated using a prospectively defined hierarchical testing procedure and treatment-by-covariate interaction for overall survival (OS) based on LL1. RESULTS: Time since start of first-line therapy...

  13. Constant resolution of time-dependent Hartree--Fock phase ambiguity

    International Nuclear Information System (INIS)

    Lichtner, P.C.; Griffin, J.J.; Schultheis, H.; Schultheis, R.; Volkov, A.B.

    1978-01-01

    The customary time-dependent Hartree--Fock problem is shown to be ambiguous up to an arbitrary function of time additive to H/sub HF/, and, consequently, up to an arbitrary time-dependent phase for the solution, PHI(t). The ''constant'' (H)'' phase is proposed as the best resolution of this ambiguity. It leads to the following attractive features: (a) the time-dependent Hartree--Fock (TDHF) Hamiltonian, H/sub HF/, becomes a quantity whose expectation value is equal to the average energy and, hence, constant in time; (b) eigenstates described exactly by determinants, have time-dependent Hartree--Fock solutions identical with the exact time-dependent solutions; (c) among all possible TDHF solutions this choice minimizes the norm of the quantity (H--i dirac constant delta/delta t) operating on the ket PHI, and guarantees optimal time evolution over an infinitesimal period; (d) this choice corresponds both to the stationary value of the absolute difference between (H) and (i dirac constant delta/delta t) and simultaneously to its absolute minimal value with respect to choice of the time-dependent phase. The source of the ambiguity is discussed. It lies in the time-dependent generalization of the freedom to transform unitarily among the single-particle states of a determinant at the (physically irrelevant for stationary states) cost of altering only a factor of unit magnitude

  14. Help Wanted: Exploring the Value of Entrepreneurial Mentoring at Start-Up

    Science.gov (United States)

    Brodie, Jacqueline; Van Saane, Sebastiaan Huib; Osowska, Renata

    2017-01-01

    The purpose of the research presented in this article was to investigate the added value of mentoring for entrepreneurs during the start-up phase. This small-scale exploratory research focused on five start-up entrepreneurs in Scotland to determine the entrepreneurs' perceptions regarding the "added" value of their mentoring support. To…

  15. START: an advanced radiation therapy information system.

    Science.gov (United States)

    Cocco, A; Valentini, V; Balducci, M; Mantello, G

    1996-01-01

    START is an advanced radiation therapy information system (RTIS) which connects direct information technology present in the devices with indirect information technology for clinical, administrative, information management integrated with the hospital information system (HIS). The following objectives are pursued: to support decision making in treatment planning and functional and information integration with the rest of the hospital; to enhance organizational efficiency of a Radiation Therapy Department; to facilitate the statistical evaluation of clinical data and managerial performance assessment; to ensure the safety and confidentiality of used data. For its development a working method based on the involvement of all operators of the Radiation Therapy Department, was applied. Its introduction in the work activity was gradual, trying to reuse and integrate the existing information applications. The START information flow identifies four major phases: admission, visit of admission, planning, therapy. The system main functionalities available to the radiotherapist are: clinical history/medical report linking function; folder function; planning function; tracking function; electronic mail and banner function; statistical function; management function. Functions available to the radiotherapy technician are: the room daily list function; management function: to the nurse the following functions are available: patient directing function; management function. START is a departmental client (pc-windows)-server (unix) developed on an integrated database of all information of interest (clinical, organizational and administrative) coherent with the standard and with a modular architecture which can evolve with additional functionalities in subsequent times. For a more thorough evaluation of its impact on the daily activity of a radiation therapy facility, a prolonged clinical validation is in progress.

  16. The Gift of Time? School Starting Age and Mental Health

    DEFF Research Database (Denmark)

    Sievertsen, Hans Henrik; S. Dee, Thomas

    2018-01-01

    influences student outcomes by relying on linked Danish survey and register data that include several distinct, widely used, and validated measures of mental health that are reported out-of-school among similarly aged children. We estimate the causal effects of delayed school enrollment using a "fuzzy.......7), a measure of self regulation with strong negative links to student achievement. We also find that this large and targeted effect persists at age 11. However, the estimated effects of school starting age on other mental-health constructs, which have weaker links to subsequent student achievement, are smaller......In many developed countries, children now begin their formal schooling at an older age. However, a growing body of empirical studies provides little evidence that such schooling delays improve educational and economic outcomes. This study presents new evidence on whether school starting age...

  17. Relationship Between Final Performance and Block Times with the Traditional and the New Starting Platforms with A Back Plate in International Swimming Championship 50-M and 100-M Freestyle Events

    Science.gov (United States)

    Garcia-Hermoso, Antonio; Escalante, Yolanda; Arellano, Raul; Navarro, Fernando; Domínguez, Ana M.; Saavedra, Jose M.

    2013-01-01

    The purpose of this study was to investigate the association between block time and final performance for each sex in 50-m and 100-m individual freestyle, distinguishing between classification (1st to 3rd, 4th to 8th, 9th to 16th) and type of starting platform (old and new) in international competitions. Twenty-six international competitions covering a 13-year period (2000-2012) were analysed retrospectively. The data corresponded to a total of 1657 swimmers’ competition histories. A two-way ANOVA (sex x classification) was performed for each event and starting platform with the Bonferroni post-hoc test, and another two-way ANOVA for sex and starting platform (sex x starting platform). Pearson’s simple correlation coefficient was used to determine correlations between the block time and the final performance. Finally, a simple linear regression analysis was done between the final time and the block time for each sex and platform. The men had shorter starting block times than the women in both events and from both platforms. For 50-m event, medalists had shorter block times than semi- finalists with the old starting platforms. Block times were directly related to performance with the old starting platforms. With the new starting platforms, however, the relationship was inverse, notably in the women’s 50-m event. The block time was related for final performance in the men’s 50- m event with the old starting platform, but with the new platform it was critical only for the women’s 50-m event. Key Points The men had shorter block times than the women in both events and with both platforms. For both distances, the swimmers had shorter block times in their starts from the new starting platform with a back plate than with the old platform. For the 50-m event with the old starting platform, the medalists had shorter block times than the semi-finalists. The new starting platform block time was only determinant in the women’s 50-m event. In order to improve

  18. Real time NO emissions measurement during cold start in LPG SI engine

    International Nuclear Information System (INIS)

    Li, Gong; Liu, Zhimin; Li, Zhilong; Qiu, Dongping; Li, Liguang

    2007-01-01

    To identify combustion occurrence is very important. Traditionally, cylinder pressure has been used as a criterion of combustion occurrence, but it can be unreliable when identifying lean mixture combustion (there is little difference in the cylinder pressure trace between the firing cycle and motoring cycles at the lean combustion limit). This is particularly important for fuels like LPG, which have a good capacity for lean combustion. In this study, a fast response NO detector, CambustionfNOx400, based on the chemiluminescence method, was used to measure real time NO emissions in order to evaluate the technique as a criterion for establishing combustion occurrence. At the same time, this paper presents an investigation of the characteristics of real time NO emissions of the first firing cycle during cold start in a LPG SI engine to determine the optimal excess air factor of the first firing cycle, and the cylinder pressure and crank shaft speed of the engine were measured and recorded. Test results show that the excess air ratio directly influences the cylinder pressure, engine speed and NO emissions of the first firing cycle. As the excess air coefficient is reduced from the lean misfiring limit, NO emissions increase quickly, then reduce quickly and then reduce slowly. NO emissions generally increase with peak cylinder pressure, even at constant excess air coefficient. Real time NO emissions can be used to identify cylinder combustion and misfire occurrence during engine cranking, even at the dilute combustion limit, and real time NO emission can be used to understand the combustion and misfire occurrence. (author)

  19. Human Adolescent Phase Response Curves to Bright White Light.

    Science.gov (United States)

    Crowley, Stephanie J; Eastman, Charmane I

    2017-08-01

    Older adolescents are particularly vulnerable to circadian misalignment and sleep restriction, primarily due to early school start times. Light can shift the circadian system and could help attenuate circadian misalignment; however, a phase response curve (PRC) to determine the optimal time for receiving light and avoiding light is not available for adolescents. We constructed light PRCs for late pubertal to postpubertal adolescents aged 14 to 17 years. Participants completed 2 counterbalanced 5-day laboratory sessions after 8 or 9 days of scheduled sleep at home. Each session included phase assessments to measure the dim light melatonin onset (DLMO) before and after 3 days of free-running through an ultradian light-dark (wake-sleep) cycle (2 h dim [~20 lux] light, 2 h dark). In one session, intermittent bright white light (~5000 lux; four 20-min exposures) was alternated with 10 min of dim room light once per day for 3 consecutive days. The time of light varied among participants to cover the 24-h day. For each individual, the phase shift to bright light was corrected for the free-run derived from the other laboratory session with no bright light. One PRC showed phase shifts in response to light start time relative to the DLMO and another relative to home sleep. Phase delay shifts occurred around the hours corresponding to home bedtime. Phase advances occurred during the hours surrounding wake time and later in the afternoon. The transition from delays to advances occurred at the midpoint of home sleep. The adolescent PRCs presented here provide a valuable tool to time bright light in adolescents.

  20. Start-up and commercial operation of the Laguna Verde power plants, unit 1

    International Nuclear Information System (INIS)

    Torres R, J.F.

    1991-01-01

    The main features of the unit 1 of the Laguna Verde Power Plant is presented as well as the phases of the start-up process. The process includes various steps and tests up to start the commercial operation. (author)

  1. Confirming the timing of phase-based costing in oncology studies: a case example in advanced melanoma.

    Science.gov (United States)

    Atkins, Michael; Coutinho, Anna D; Nunna, Sasikiran; Gupte-Singh, Komal; Eaddy, Michael

    2018-02-01

    The utilization of healthcare services and costs among patients with cancer is often estimated by the phase of care: initial, interim, or terminal. Although their durations are often set arbitrarily, we sought to establish data-driven phases of care using joinpoint regression in an advanced melanoma population as a case example. A retrospective claims database study was conducted to assess the costs of advanced melanoma from distant metastasis diagnosis to death during January 2010-September 2014. Joinpoint regression analysis was applied to identify the best-fitting points, where statistically significant changes in the trend of average monthly costs occurred. To identify the initial phase, average monthly costs were modeled from metastasis diagnosis to death; and were modeled backward from death to metastasis diagnosis for the terminal phase. Points of monthly cost trend inflection denoted ending and starting points. The months between represented the interim phase. A total of 1,671 patients with advanced melanoma who died met the eligibility criteria. Initial phase was identified as the 5-month period starting with diagnosis of metastasis, after which there was a sharp, significant decline in monthly cost trend (monthly percent change [MPC] = -13.0%; 95% CI = -16.9% to -8.8%). Terminal phase was defined as the 5-month period before death (MPC = -14.0%; 95% CI = -17.6% to -10.2%). The claims-based algorithm may under-estimate patients due to misclassifications, and may over-estimate terminal phase costs because hospital and emergency visits were used as a death proxy. Also, recently approved therapies were not included, which may under-estimate advanced melanoma costs. In this advanced melanoma population, optimal duration of the initial and terminal phases of care was 5 months immediately after diagnosis of metastasis and before death, respectively. Joinpoint regression can be used to provide data-supported phase of cancer care durations, but

  2. Molecular quantum control landscapes in von Neumann time-frequency phase space

    Science.gov (United States)

    Ruetzel, Stefan; Stolzenberger, Christoph; Fechner, Susanne; Dimler, Frank; Brixner, Tobias; Tannor, David J.

    2010-10-01

    Recently we introduced the von Neumann representation as a joint time-frequency description for femtosecond laser pulses and suggested its use as a basis for pulse shaping experiments. Here we use the von Neumann basis to represent multidimensional molecular control landscapes, providing insight into the molecular dynamics. We present three kinds of time-frequency phase space scanning procedures based on the von Neumann formalism: variation of intensity, time-frequency phase space position, and/or the relative phase of single subpulses. The shaped pulses produced are characterized via Fourier-transform spectral interferometry. Quantum control is demonstrated on the laser dye IR140 elucidating a time-frequency pump-dump mechanism.

  3. Kalman filters for real-time magnetic island phase tracking

    NARCIS (Netherlands)

    Borgers, D. P.; Lauret, M.; M.R. de Baar,

    2013-01-01

    For control of neoclassical tearing modes (NTMs) and the resulting rotating magnetic islands in tokamak plasmas, the frequency and phase of the magnetic islands need to be accurately tracked in real-time. In previous experiments on TEXTOR, this was achieved using a phase-locked loop (PLL). For ASDEX

  4. An Integrated Start-Up Method for Pumped Storage Units Based on a Novel Artificial Sheep Algorithm

    Directory of Open Access Journals (Sweden)

    Zanbin Wang

    2018-01-01

    Full Text Available Pumped storage units (PSUs are an important storage tool for power systems containing large-scale renewable energy, and the merit of rapid start-up enable PSUs to modulate and stabilize the power system. In this paper, PSU start-up strategies have been studied and a new integrated start-up method has been proposed for the purpose of achieving swift and smooth start-up. A two-phase closed-loop startup strategy, composed of switching Proportion Integration (PI and Proportion Integration Differentiation (PID controller is designed, and an integrated optimization scheme is proposed for a synchronous optimization of the parameters in the strategy. To enhance the optimization performance, a novel meta-heuristic called Artificial Sheep Algorithm (ASA is proposed and applied to solve the optimization task after a sufficient verification with seven popular meta-heuristic algorithms and 13 typical benchmark functions. Simulation model has been built for a China’s PSU and comparative experiments are conducted to evaluate the proposed integrated method. Results show that the start-up performance could be significantly improved on both indices on overshoot and start-up, and up to 34%-time consumption has been reduced under different working condition. The significant improvements on start-up of PSU is interesting and meaning for further application on real unit.

  5. Time gated phase-correlation distributed Brillouin fibre sensor

    Science.gov (United States)

    Denisov, Andrey; Soto, Marcelo A.; Thévenaz, Luc

    2013-05-01

    A random access distributed Brillouin fibre sensor is presented, based on phase modulation using a pseudo-random bit sequence (PRBS) together with time gating. The standard phase-correlation technique is known to show a noise level increasing linearly with the number of measured points due to weak gratings generated randomly along the whole sensing fibre. Here we show how intensity modulated pump and time gated detection significantly improve the signal-tonoise ratio (SNR) of the system with no impact on the spatial resolution. A measurement with 1.1 cm spatial resolution over 3.3 km is demonstrated, representing 300'000 equivalent points. The limitations of the proposed technique are discussed through the paper.

  6. The three phases of time-limited day-hospital treatment.

    Science.gov (United States)

    Stein, H H; Hirsch, B; Brenman, S; Bataclan, L

    1990-06-01

    The course of treatment in a time-limited day-hospital setting can be usefully understood in terms of three phases. Close examination of the treatment goals, difficulties, benefits, and tasks for both patients and staff for each phase provides a greater understanding of the curative process. These observations are based upon clinical work in a Veteran Administration Day Hospital and are reinforced with clinical examples from that work. Identification of these phases of treatment can be put to practical use. Knowing in which phase a patient is working helps staff members focus their thinking. Such an awareness can also help staff members cope with "burnout" over the frustrations that come with a particular phase. Information about these phases has been valuable to patients and their families in helping them understand the course of their treatment.

  7. The effect of handover location on trauma theatre start time: An estimated cost saving of £131 000 per year.

    Science.gov (United States)

    Nahas, Sam; Ali, Adam; Majid, Kiran; Joseph, Roshan; Huber, Chris; Babu, Victor

    2018-02-08

    The National Health Service was estimated to be in £2.45 billion deficit in 2015 to 2016. Trauma theatre utilization and efficiency has never been so important as it is estimated to cost £15/minute. Structured questionnaires were given to 23 members of staff at our Trust who are actively involved in the organization or delivery of orthopaedic trauma lists at least once per week. This was used to identify key factors that may improve theatre efficiency. Following focus group evaluation, the location of the preoperative theatre meeting was changed, with all staff involved being required to attend this. Our primary outcome measure was mean theatre start time (time of arrival in the anaesthetic room) during the 1 month immediately preceding the change and the month following the change. Theatre start time was improved on average 24 minutes (1 month premeeting and postmeeting change). This equates to a saving of £360 per day, or £131 040 per year. Changing the trauma meeting location to a venue adjacent to the trauma theatre can improve theatre start times, theatre efficiency, and therefore result in significant cost savings. Copyright © 2018 John Wiley & Sons, Ltd.

  8. Real-time Astrometry Using Phase Congruency

    Science.gov (United States)

    Lambert, A.; Polo, M.; Tang, Y.

    Phase congruency is a computer vision technique that proves to perform well for determining the tracks of optical objects (Flewelling, AMOS 2014). We report on a real-time implementation of this using an FPGA and CMOS Image Sensor, with on-sky data. The lightweight instrument can provide tracking update signals to the mount of the telescope, as well as determine abnormal objects in the scene.

  9. Relationship Between Final Performance and Block Times with the Traditional and the New Starting Platforms with A Back Plate in International Swimming Championship 50-M and 100-M Freestyle Events

    Directory of Open Access Journals (Sweden)

    Antonio Garcia-Hermoso

    2013-12-01

    Full Text Available The purpose of this study was to investigate the association between block time and final performance for each sex in 50-m and 100-m individual freestyle, distinguishing between classification (1st to 3rd, 4th to 8th, 9th to 16th and type of starting platform (old and new in international competitions. Twenty-six international competitions covering a 13-year period (2000-2012 were analysed retrospectively. The data corresponded to a total of 1657 swimmers’ competition histories. A two-way ANOVA (sex x classification was performed for each event and starting platform with the Bonferroni post-hoc test, and another two-way ANOVA for sex and starting platform (sex x starting platform. Pearson’s simple correlation coefficient was used to determine correlations between the block time and the final performance. Finally, a simple linear regression analysis was done between the final time and the block time for each sex and platform. The men had shorter starting block times than the women in both events and from both platforms. For 50-m event, medalists had shorter block times than semi- finalists with the old starting platforms. Block times were directly related to performance with the old starting platforms. With the new starting platforms, however, the relationship was inverse, notably in the women’s 50-m event. The block time was related for final performance in the men’s 50- m event with the old starting platform, but with the new platform it was critical only for the women’s 50-m event.

  10. Start-up of plasma current by electron Bernstein wave

    International Nuclear Information System (INIS)

    Maekawa, Takashi; Tanaka, Hitoshi; Uehide, Masaki

    2009-01-01

    Electron cyclotron current drive by electron Bernstein (EB) waves for the start-up and ramp-up of toroidal plasma current with no central solenoid in tokamaks is discussed. It is shown that high N// EB waves have ability to ramp-up the current against the counter voltage from self-induction, where N// is the parallel refractive index to the magnetic field, and they are especially suitable for initial current start-up phase where the bulk electron temperature is low enough to ensure high N// EB waves. (author)

  11. Press Start

    Science.gov (United States)

    Harteveld, Casper

    This level sets the stage for the design philosophy called “Triadic Game Design” (TGD). This design philosophy can be summarized with the following sentence: it takes two to tango, but it takes three to design a meaningful game or a game with a purpose. Before the philosophy is further explained, this level will first delve into what is meant by a meaningful game or a game with a purpose. Many terms and definitions have seen the light and in this book I will specifically orient at digital games that aim to have an effect beyond the context of the game itself. Subsequently, a historical overview is given of the usage of games with a serious purpose which starts from the moment we human beings started to walk on our feet till our contemporary society. It turns out that we have been using games for all kinds of non-entertainment purposes for already quite a long time. With this introductory material in the back of our minds, I will explain the concept of TGD by means of a puzzle. After that, the protagonist of this book, the game Levee Patroller, is introduced. Based on the development of this game, the idea of TGD, which stresses to balance three different worlds, the worlds of Reality, Meaning, and Play, came into being. Interested? Then I suggest to quickly “press start!”

  12. A cross-cultural comparison of sleep duration between US And Australian adolescents: the effect of school start time, parent-set bedtimes, and extracurricular load.

    Science.gov (United States)

    Short, Michelle A; Gradisar, Michael; Lack, Leon C; Wright, Helen R; Dewald, Julia F; Wolfson, Amy R; Carskadon, Mary A

    2013-06-01

    To test whether sleep duration on school nights differs between adolescents in Australia and the United States and, if so, whether this difference is explained by cultural differences in school start time, parental involvement in setting bedtimes, and extracurricular commitments. Three hundred eighty-five adolescents aged 13 to 18 years (M = 15.57, SD = 0.95; 60% male) from Australia and 302 adolescents aged 13 to 19 years (M = 16.03, SD = 1.19; 35% male) from the United States. Adolescents completed the School Sleep Habits Survey during class time, followed by an 8-day sleep diary. After controlling for age and gender, Australian adolescents obtained an average of 47 minutes more sleep per school night than those in the United States. Australian adolescents were more likely to have a parent-set bedtime (17.5% vs. 6.8%), have a later school start time (8:32 a.m. vs. 7:45 a.m.), and spend less time per day on extracurricular commitments (1 h 37 min vs. 2 h 41 min) than their U.S. peers. The mediating factors of parent-set bedtimes, later school start times, and less time spent on extracurricular activities were significantly associated with more total sleep. In addition to biological factors, extrinsic cultural factors significantly affect adolescent sleep. The present study highlights the importance of a cross-cultural, ecological approach and the impact of early school start times, lack of parental limit setting around bedtimes, and extracurricular load in limiting adolescent sleep.

  13. Characteristics of Young Children Exposed to Violence: The Safe Start Demonstration Project

    Science.gov (United States)

    Kaufman, Joy S.; Ortega, Sandra; Schewe, Paul A.; Kracke, Kristen

    2011-01-01

    The Safe Start demonstration projects, funded by the Office of Juvenile Justice and Delinquency Prevention (OJJDP) under the first phase of the Safe Start initiative, are primarily designed to influence change at the systems or macrolevels to reduce the incidence of and impact of exposure to violence for children aged birth to 6 years; direct…

  14. A review of start-up operations on the first units of the 1300 MWe generation

    International Nuclear Information System (INIS)

    Meclot, B.; Lemagny Boc Lonlaygue, C.; Lavogiez, M.

    1986-01-01

    This paper describes and offers comments on the different phases of start-up on power stations of the P4 series. Then, one reviews incidents which occurred in the course of these start-up phases and, having highlighted the lessons to be learnt from the commissioning of these power stations, goes on to make a comparative study of 1300 and 900 MWe availability in the initial year of operation [fr

  15. Time-resolved dynamics of nanosecond laser-induced phase explosion

    International Nuclear Information System (INIS)

    Porneala, Cristian; Willis, David A

    2009-01-01

    Visualization of Nd : YAG laser ablation of aluminium targets was performed by a shadowgraph apparatus capable of imaging the dynamics of ablation with nanosecond time resolution. Direct observations of vaporization, explosive phase change and shock waves were obtained. The influence of vaporization and phase explosion on shock wave velocity was directly measured. A significant increase in the shock wave velocity was observed at the onset of phase explosion. However, the shock wave behaviour followed the form of a Taylor-Sedov spherical shock below and above the explosive phase change threshold. The jump in the shock wave velocity above phase explosion threshold is attributed to the release of stored enthalpy in the superheated liquid surface. The energy released during phase explosion was estimated by fitting the transient shock wave position to the Taylor scaling rules. Results of temperature calculations indicate that the vapour temperature at the phase explosion threshold is slightly higher than the critical temperature at the early stages of the shock wave formation. The shock wave pressure nearly doubled when transitioning from normal vaporization to phase explosion.

  16. A digital, constant-frequency pulsed phase-locked-loop instrument for real-time, absolute ultrasonic phase measurements

    Science.gov (United States)

    Haldren, H. A.; Perey, D. F.; Yost, W. T.; Cramer, K. E.; Gupta, M. C.

    2018-05-01

    A digitally controlled instrument for conducting single-frequency and swept-frequency ultrasonic phase measurements has been developed based on a constant-frequency pulsed phase-locked-loop (CFPPLL) design. This instrument uses a pair of direct digital synthesizers to generate an ultrasonically transceived tone-burst and an internal reference wave for phase comparison. Real-time, constant-frequency phase tracking in an interrogated specimen is possible with a resolution of 0.000 38 rad (0.022°), and swept-frequency phase measurements can be obtained. Using phase measurements, an absolute thickness in borosilicate glass is presented to show the instrument's efficacy, and these results are compared to conventional ultrasonic pulse-echo time-of-flight (ToF) measurements. The newly developed instrument predicted the thickness with a mean error of -0.04 μm and a standard deviation of error of 1.35 μm. Additionally, the CFPPLL instrument shows a lower measured phase error in the absence of changing temperature and couplant thickness than high-resolution cross-correlation ToF measurements at a similar signal-to-noise ratio. By showing higher accuracy and precision than conventional pulse-echo ToF measurements and lower phase errors than cross-correlation ToF measurements, the new digitally controlled CFPPLL instrument provides high-resolution absolute ultrasonic velocity or path-length measurements in solids or liquids, as well as tracking of material property changes with high sensitivity. The ability to obtain absolute phase measurements allows for many new applications than possible with previous ultrasonic pulsed phase-locked loop instruments. In addition to improved resolution, swept-frequency phase measurements add useful capability in measuring properties of layered structures, such as bonded joints, or materials which exhibit non-linear frequency-dependent behavior, such as dispersive media.

  17. Assessment of Multivariate Neural Time Series by Phase Synchrony Clustering in a Time-Frequency-Topography Representation

    Directory of Open Access Journals (Sweden)

    M. A. Porta-Garcia

    2018-01-01

    Full Text Available Most EEG phase synchrony measures are of bivariate nature. Those that are multivariate focus on producing global indices of the synchronization state of the system. Thus, better descriptions of spatial and temporal local interactions are still in demand. A framework for characterization of phase synchrony relationships between multivariate neural time series is presented, applied either in a single epoch or over an intertrial assessment, relying on a proposed clustering algorithm, termed Multivariate Time Series Clustering by Phase Synchrony, which generates fuzzy clusters for each multivalued time sample and thereupon obtains hard clusters according to a circular variance threshold; such cluster modes are then depicted in Time-Frequency-Topography representations of synchrony state beyond mere global indices. EEG signals from P300 Speller sessions of four subjects were analyzed, obtaining useful insights of synchrony patterns related to the ERP and even revealing steady-state artifacts at 7.6 Hz. Further, contrast maps of Levenshtein Distance highlight synchrony differences between ERP and no-ERP epochs, mainly at delta and theta bands. The framework, which is not limited to one synchrony measure, allows observing dynamics of phase changes and interactions among channels and can be applied to analyze other cognitive states rather than ERP versus no ERP.

  18. Pecularities of the start-up process in a toroidal Extrap

    International Nuclear Information System (INIS)

    Tendler, M.

    1986-08-01

    The breakdown, occuring in the EXTRAP system, in which a plasma is immersed in the purely poloidal, strongly inhomogeneous external magnetic field, is analyzed. The division into four subsequent phases of the development of these discharges is presented. It is shown that the toroidicity, the lack of electrodes and the external magnetic field strongly affects the breakdown conditions. It is emphasized that, in the presence of the external magnetic field, the internal radial electric field has to be taken into account. Two different options for the start-up scenaria are described. The discharge might either develop along the 0-line or at the periphery of the discharge. The essential parameters, which govern the development are shown to be the skin depth in the breakdown phase and the degree of the magnetization. The advantages and the disadvantages of these different scenaria are listed. It is pointed out that if the discharge starts along the 0-line the ionization might be full only in the close vicinity of this line. Methods to improve the axial homogeneity during the breakdown phase are described. (author)

  19. Adaptation to shift work: physiologically based modeling of the effects of lighting and shifts' start time.

    Directory of Open Access Journals (Sweden)

    Svetlana Postnova

    Full Text Available Shift work has become an integral part of our life with almost 20% of the population being involved in different shift schedules in developed countries. However, the atypical work times, especially the night shifts, are associated with reduced quality and quantity of sleep that leads to increase of sleepiness often culminating in accidents. It has been demonstrated that shift workers' sleepiness can be improved by a proper scheduling of light exposure and optimizing shifts timing. Here, an integrated physiologically-based model of sleep-wake cycles is used to predict adaptation to shift work in different light conditions and for different shift start times for a schedule of four consecutive days of work. The integrated model combines a model of the ascending arousal system in the brain that controls the sleep-wake switch and a human circadian pacemaker model. To validate the application of the integrated model and demonstrate its utility, its dynamics are adjusted to achieve a fit to published experimental results showing adaptation of night shift workers (n = 8 in conditions of either bright or regular lighting. Further, the model is used to predict the shift workers' adaptation to the same shift schedule, but for conditions not considered in the experiment. The model demonstrates that the intensity of shift light can be reduced fourfold from that used in the experiment and still produce good adaptation to night work. The model predicts that sleepiness of the workers during night shifts on a protocol with either bright or regular lighting can be significantly improved by starting the shift earlier in the night, e.g.; at 21:00 instead of 00:00. Finally, the study predicts that people of the same chronotype, i.e. with identical sleep times in normal conditions, can have drastically different responses to shift work depending on their intrinsic circadian and homeostatic parameters.

  20. Adaptation to shift work: physiologically based modeling of the effects of lighting and shifts' start time.

    Science.gov (United States)

    Postnova, Svetlana; Robinson, Peter A; Postnov, Dmitry D

    2013-01-01

    Shift work has become an integral part of our life with almost 20% of the population being involved in different shift schedules in developed countries. However, the atypical work times, especially the night shifts, are associated with reduced quality and quantity of sleep that leads to increase of sleepiness often culminating in accidents. It has been demonstrated that shift workers' sleepiness can be improved by a proper scheduling of light exposure and optimizing shifts timing. Here, an integrated physiologically-based model of sleep-wake cycles is used to predict adaptation to shift work in different light conditions and for different shift start times for a schedule of four consecutive days of work. The integrated model combines a model of the ascending arousal system in the brain that controls the sleep-wake switch and a human circadian pacemaker model. To validate the application of the integrated model and demonstrate its utility, its dynamics are adjusted to achieve a fit to published experimental results showing adaptation of night shift workers (n = 8) in conditions of either bright or regular lighting. Further, the model is used to predict the shift workers' adaptation to the same shift schedule, but for conditions not considered in the experiment. The model demonstrates that the intensity of shift light can be reduced fourfold from that used in the experiment and still produce good adaptation to night work. The model predicts that sleepiness of the workers during night shifts on a protocol with either bright or regular lighting can be significantly improved by starting the shift earlier in the night, e.g.; at 21:00 instead of 00:00. Finally, the study predicts that people of the same chronotype, i.e. with identical sleep times in normal conditions, can have drastically different responses to shift work depending on their intrinsic circadian and homeostatic parameters.

  1. Adaptation to Shift Work: Physiologically Based Modeling of the Effects of Lighting and Shifts’ Start Time

    Science.gov (United States)

    Postnova, Svetlana; Robinson, Peter A.; Postnov, Dmitry D.

    2013-01-01

    Shift work has become an integral part of our life with almost 20% of the population being involved in different shift schedules in developed countries. However, the atypical work times, especially the night shifts, are associated with reduced quality and quantity of sleep that leads to increase of sleepiness often culminating in accidents. It has been demonstrated that shift workers’ sleepiness can be improved by a proper scheduling of light exposure and optimizing shifts timing. Here, an integrated physiologically-based model of sleep-wake cycles is used to predict adaptation to shift work in different light conditions and for different shift start times for a schedule of four consecutive days of work. The integrated model combines a model of the ascending arousal system in the brain that controls the sleep-wake switch and a human circadian pacemaker model. To validate the application of the integrated model and demonstrate its utility, its dynamics are adjusted to achieve a fit to published experimental results showing adaptation of night shift workers (n = 8) in conditions of either bright or regular lighting. Further, the model is used to predict the shift workers’ adaptation to the same shift schedule, but for conditions not considered in the experiment. The model demonstrates that the intensity of shift light can be reduced fourfold from that used in the experiment and still produce good adaptation to night work. The model predicts that sleepiness of the workers during night shifts on a protocol with either bright or regular lighting can be significantly improved by starting the shift earlier in the night, e.g.; at 21∶00 instead of 00∶00. Finally, the study predicts that people of the same chronotype, i.e. with identical sleep times in normal conditions, can have drastically different responses to shift work depending on their intrinsic circadian and homeostatic parameters. PMID:23308206

  2. Changing Incidence and Risk Factors for Kaposi Sarcoma by Time Since Starting Antiretroviral Therapy

    DEFF Research Database (Denmark)

    Wyss, Natascha; Zwahlen, Marcel; Bohlius, Julia

    2016-01-01

    BACKGROUND:  Kaposi sarcoma (KS) remains a frequent cancer in human immunodeficiency virus (HIV)-positive patients starting combination antiretroviral therapy (cART). We examined incidence rates and risk factors for developing KS in different periods after starting cART in patients from European...

  3. Three types of preS1 start codon deletion variants in the natural course of chronic hepatitis B infection.

    Science.gov (United States)

    Choe, Won Hyeok; Kim, Hong; Lee, So-Young; Choi, Yu-Min; Kwon, So Young; Moon, Hee Won; Hur, Mina; Kim, Bum-Joon

    2017-12-12

    Naturally occurring hepatitis B virus variants carrying a deletion in the preS1 start codon region may evolve during long-lasting virus-host interactions in chronic hepatitis B (CHB). The aim of this study was to determine the immune phase-specific prevalent patterns of preS1 start codon deletion variants and related factors during the natural course of CHB. A total of 399 CHB patients were enrolled. Genotypic analysis of three different preS1 start codon deletion variants (classified by deletion size: 15-base pair [bp], 18-bp, and 21-bp deletion variants) was performed. PreS1 start codon deletion variants were detected in 155 of 399 patients (38.8%). The predominant variant was a 15-bp deletion in the immune-tolerance phase (18/50, 36%) and an 18-bp deletion in the immune-clearance phase (69/183, 37.7%). A 21-bp deletion was the predominant variant in the low replicative phase (3/25, 12.0%) and reactivated hepatitis Be antigen (HBeAg)-negative phase (22/141, 15.6%). The 15-bp and 18-bp deletion variants were more frequently found in HBeAg-positive patients (P start codon deletion variants changes according to the immune phases of CHB infection, and each variant type is associated with different clinical parameters. PreS1 start codon deletion variants might interact with the host immune response differently according to their variant types. © 2017 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.

  4. Modeling of flashing-induced instabilities in the start-up phase of natural-circulation BWRs using the two-phase flow code FLOCAL

    Energy Technology Data Exchange (ETDEWEB)

    Manera, A. [Forschungszentrum Rossendorf e.V. (FZR), Institute of Safety Research, P.O.B. 510119, D-01324 Dresden (Germany) and Interfaculty Reactor Institute, Delft University of Technology, Mekelweg 15, 2629 JB Delft (Netherlands)]. E-mail: a.manera@fz-rossendorf.de; Rohde, U. [Forschungszentrum Rossendorf e.V. (FZR), Institute of Safety Research, P.O.B. 510119, D-01324 Dresden (Germany); Prasser, H.-M. [Forschungszentrum Rossendorf e.V. (FZR), Institute of Safety Research, P.O.B. 510119, D-01324 Dresden (Germany); Hagen, T.H.J.J. van der [Interfaculty Reactor Institute, Delft University of Technology, Mekelweg 15, 2629 JB Delft (Netherlands)

    2005-06-01

    This paper reports on the modeling and simulation of flashing-induced instabilities in natural-circulation systems, with special emphasis on natural-circulation boiling water reactors (BWRs). For the modeling the 4-equation two-phase model FLOCAL [Rohde, U., 1986. Ein teoretisches Modell fur Zweiphasen-stromungen in wassergekulthen Kernreaktoren und seine Anwendung zur Analyse des Naturumlaufs im Heizreaktor AST-500. Ph.D. dissertation, Akademie der Wissenschaften der DDR, Dresden], developed at the Forschungszentrum Rossendorf (FZR, Germany), has been used. The model allows for the liquid and vapor to be in thermal non-equilibrium and, via drift-flux models, to have different velocities. The phenomenology of the instability has been studied and the dominating physical effects have been determined. The results of the simulations have been compared qualitatively and quantitatively with experiments [Manera, A., van der Hagen, T.H.J.J., 2003. Stability of natural-circulation-cooled boiling water reactor during start up: experimental results. Nuc. Technol., 143] that have been carried out within the framework of a European project (NACUSP) on the CIRCUS facility. The facility, built at the Delft University of Technology in The Netherlands, is a water/steam 1:1 height-scaled loop of a typical natural-circulation-cooled BWR.

  5. On the possibility of superconducting phase coherence through time barriers

    International Nuclear Information System (INIS)

    Barone, A.; Kulik, I.O.

    1993-01-01

    The possibility of the occurrence of weak coupling between the superconducting order parameters in a single superconductor before and after an ultrashot quenching of superconductivity, is analyzed. The time barrier corresponding to such a quenching of the order parameter has to be shorter than, or comparable with, the characteristic 'coherence time' τ ∼ = Δ. Such an effect is somewhat analogous to a Josephson effect in which phase difference is now considered in the time domain rather than in space. A qualitative derivation of the constitutive relation for such a weak time correlation is obtained which gives, by the duality condition, a dependence of the supercharge on the time phase difference. The role of high-T c superconductors in the detection of this coherent transient response appears to be quite relevant. 21 refs., 4 figs

  6. Are the new starting block facilities beneficial for backstroke start performance?

    Science.gov (United States)

    de Jesus, Karla; de Jesus, Kelly; Abraldes, J Arturo; Medeiros, Alexandre Igor Araripe; Fernandes, Ricardo J; Vilas-Boas, João Paulo

    2016-01-01

    We aimed to analyse the handgrip positioning and the wedge effects on the backstroke start performance and technique. Ten swimmers completed randomly eight 15 m backstroke starts (four with hands on highest horizontal and four on vertical handgrip) performed with and without wedge. One surface and one underwater camera recorded kinematic data. Standardised mean difference (SMD) and 95% confidence intervals (CI) were used. Handgrip positioning did not affect kinematics with and without wedge use. Handgrips horizontally positioned and feet over wedge displayed greater knee angular velocity than without it (SMD = -0.82; 95% CI: -1.56, -0.08). Hands vertically positioned and feet over wedge presented greater take-off angle (SMD = -0.81; 95% CI: -1.55, -0.07), centre of mass (CM) vertical positioning at first water contact (SMD = -0.97; 95% CI: -1.87, -0.07) and CM vertical velocity at CM immersion (SMD = 1.03; 95% CI: 0.08, 1.98) when comparing without wedge use. Swimmers extended the hip previous to the knee and ankle joints, except for the variant with hands vertically positioned without wedge (SMD = 0.75; 95% CI: -0.03, 1.53). Swimmers should preserve biomechanical advantages achieved during flight with variant with hands vertically positioned and wedge throughout entry and underwater phase.

  7. University Start-ups: A Better Business Model

    Science.gov (United States)

    Dehn, J.; Webley, P. W.

    2015-12-01

    Many universities look to start-up companies as a way to attract faculty, supporting research and students as traditional federal sources become harder to come by. University affiliated start-up companies can apply for a broader suite of grants, as well as market their services to a broad customer base. Often university administrators see this as a potential panacea, but national statistics show this is not the case. Rarely do universities profit significantly from their start-ups. With a success rates of around 20%, most start-ups end up costing the university money as well as faculty-time. For the faculty, assuming they want to continue in academia, a start-up is often unattractive because it commonly leads out of academia. Running a successful business as well as maintaining a strong teaching and research load is almost impossible to do at the same time. Most business models and business professionals work outside of academia, and the models taught in business schools do not merge well in a university environment. To mitigate this a new business model is proposed where university start-ups are aligned with the academic and research missions of the university. A university start-up must work within the university, directly support research and students, and the work done maintaining the business be recognized as part of the faculty member's university obligations. This requires a complex conflict of interest management plan and for the companies to be non-profit in order to not jeopardize the university's status. This approach may not work well for all universities, but would be ideal for many to conserve resources and ensure a harmonious relationship with their start-ups and faculty.

  8. Effect of main injection timing for controlling the combustion phasing of a homogeneous charge compression ignition engine using a new dual injection strategy

    International Nuclear Information System (INIS)

    Das, Pranab; Subbarao, P.M.V.; Subrahmanyam, J.P.

    2015-01-01

    Highlights: • A new dual injection concept is developed by minimum geometry modification. • The occurrence of combustion parameters strongly depend on main injection timing. • At higher load, premixed equivalence ratio dominates over main injection timing. • Retarded of main injection timing tends to retard combustion phasing. • Slightly retarded main injection timing is recommended to avoid intense knocking. - Abstract: Homogeneous charge compression ignition combustion of diesel fuel is implemented using a novel dual injection strategy. A new experimental technique is developed to modify a single cylinder direct injection diesel engine to run on homogeneous combustion mode. Effect of main injection timing is investigated covering a range from 26 to 8 crank angle degrees before top dead center with an interval of 3°. Retarded main injection timing is identified as a control strategy for delaying combustion phasing and a means of controlled combustion phasing of direct injection homogeneous charge compression ignition combustion. Two load conditions were investigated and it was observed that at higher load, start of combustion depends more on fuel air equivalence ratio than main injection timing, whereas at low load, it significantly varies with varying main injection timing. Significant improvements in smoke and oxides of nitrogen emissions are observed when compared with the baseline conventional combustion. By studying different combustion parameters, it is observed that there is an improvement in performance and emissions with marginal loss in thermal efficiency when the main injection timing is 20° before top dead center. This is identified as the optimum main injection timing for such homogeneous combustion under the same operating condition

  9. Phases of Kaluza-Klein Black Holes

    DEFF Research Database (Denmark)

    Harmark, Troels; Obers, N. A.

    2005-01-01

    We review the latest progress in understanding the phase structure of static and neutral Kaluza-Klein black holes, i.e. static and neutral solutions of pure gravity with an event horizon that asymptote to a d-dimensional Minkowski-space times a circle. We start by reviewing the (mu,n) phase diagram...... and the split-up of the phase structure into solutions with an internal SO(d-1) symmetry and solutions with Kaluza-Klein bubbles. We then discuss the uniform black string, non-uniform black string and localized black hole phases, and how those three phases are connected, involving issues such as classical...... instability and horizon-topology changing transitions. Finally, we review the bubble-black hole sequences, their place in the phase structure and interesting aspects such as the continuously infinite non-uniqueness of solutions for a given mass and relative tension....

  10. Two-Man Bobsled Push Start Analysis

    Directory of Open Access Journals (Sweden)

    Lopes Alexandre Dias

    2016-04-01

    Full Text Available The importance of push start times on bobsled performance was evidenced by some studies, but at this moment there is no article to the authors’ knowledge that describes the bobsled push start. Thus, the objectives of this study were to describe the two-man bobsled push start, analyze the differences between teams, and estimate the most important variable analyzed. We hypothesized that the pilot and brakeman athletes’ movement patterns during a bobsled pushing start can be described. The images used in this study were obtained during the men’s two-man XIV World Championship of Bobsled (2004. Fifteen best teams participating in the championship were recorded, and four start runs for each team were analyzed. The videos were captured by two digital video cameras. The pilot athletes were analyzed during the moment that they touched the lateral push bar of the sled, and the brakemen were analyzed during the first take-off and first landing. The teams were pooled in three groups of five teams using the final ranking of pushing time. We concluded that there was a distinct pattern movement for pilots and brakemen. The initial position of the majority of the pilots was localized slightly behind the bar. After touching the lateral bar, the pilots remained in a semi-squat position, pushing the sled forward in a pattern of marching movement. All brakemen used the board attached to the track as a support for both feet at the start. The brakeman gave the greatest contribution to break the inertia of the sled. There was no significant difference of movement between the three groups analyzed for the pilot and the brakeman.

  11. LHC Report: Start of intensity ramp-up before a short breather

    CERN Multimedia

    Mike Lamont for the LHC team

    2015-01-01

    The first Stable Beams on 3 June were followed, to the accompaniment of thunderstorms, by the start of a phase known as the “intensity ramp-up” which saw the LHC team deliver physics with 50 bunches per beam. Time was also taken for a special five-day run devoted principally to the LHCf experiment. This week (15-19 June) the beam-based programme of the machine and its experiments was stopped temporarily for regular maintenance work.   LHCf’s Arm1 detector. While the first stable colliding beams were delivered with only 3 nominal bunches per beam, the aim of last week’s operations was to start the process of increasing the number of bunches in the beam with an ultimate 2015 target of ~2400 bunches per beam. The number of bunches is gradually increased in well-defined steps. At each step – 3 bunches per beam, then 13, 40 and, finally, 50 – the machine protection team requests 3 fills and around 20 hours of Stable Be...

  12. [Recognition of walking stance phase and swing phase based on moving window].

    Science.gov (United States)

    Geng, Xiaobo; Yang, Peng; Wang, Xinran; Geng, Yanli; Han, Yu

    2014-04-01

    Wearing transfemoral prosthesis is the only way to complete daily physical activity for amputees. Motion pattern recognition is important for the control of prosthesis, especially in the recognizing swing phase and stance phase. In this paper, it is reported that surface electromyography (sEMG) signal is used in swing and stance phase recognition. sEMG signal of related muscles was sampled by Infiniti of a Canadian company. The sEMG signal was then filtered by weighted filtering window and analyzed by height permitted window. The starting time of stance phase and swing phase is determined through analyzing special muscles. The sEMG signal of rectus femoris was used in stance phase recognition and sEMG signal of tibialis anterior is used in swing phase recognition. In a certain tolerating range, the double windows theory, including weighted filtering window and height permitted window, can reach a high accuracy rate. Through experiments, the real walking consciousness of the people was reflected by sEMG signal of related muscles. Using related muscles to recognize swing and stance phase is reachable. The theory used in this paper is useful for analyzing sEMG signal and actual prosthesis control.

  13. The start of the harvest

    CERN Multimedia

    2011-01-01

    The first major particle physics summer conference has just started this week in Grenoble. After the Quark-Matter conference, the Europhysics Conference on High-Energy Physics marks the start of a promising harvest for the LHC experiments.   For the first time, the collaborations will be presenting their latest results based on all luminosity taken until end of June, which will provide more precise measurements in many areas. Thanks to the excellent performance of the LHC, the experiments have already accumulated a substantial quantity of data allowing them to push back the known limits and refine measurements in many fields ranging from b physics to the search for the Higgs boson and for dark matter. At the time of writing, the LHC collaborations are about to present these new results in an energy range which has never previously been explored. I have congratulated all the teams involved in getting the LHC into operation in record time with great efficiency. Today I would like to acknowledge the...

  14. The effect warming time of mechanical properties and structural phase aluminum alloy nickel

    International Nuclear Information System (INIS)

    Husna Al Hasa, M.; Anwar Muchsin

    2011-01-01

    Ferrous aluminum alloys as fuel cladding will experience the process of heat treatment above the recrystallization temperature. Temperature and time of heat treatment will affect the nature of the metal. Heating time allows will affect change in mechanical properties, thermal and structure of the metal phase. This study aims to determine the effect of time of heat treatment on mechanical properties and phase metal alloys. Testing the mechanical properties of materials, especially violence done by the method of Vickers. Observation of microstructural changes made by metallographic-optical and phase structure were analyzed Based on the x-ray diffraction patterns Elemental analysis phase alloy compounds made by EDS-SEM. Test results show the nature of violence AlFeNiMg alloy by heating at 500°C with a warm-up time 1 hour, 2 hours and 3 hours respectively decreased range 94.4 HV, 87.6 HV and 85.1 HV. The nature of violence AlFeNi alloy showed a decrease in line with the longer heating time. Metallographic-optical observations show the microstructural changes with increasing heating time. Microstructure shows the longer the heating time trend equi axial shaped grain structure of growing and the results showed a trend analyst diffraction pattern formation and phase θ α phase (FeAl3) in the alloy. (author)

  15. Evidence for a time-invariant phase variable in human ankle control.

    Directory of Open Access Journals (Sweden)

    Robert D Gregg

    Full Text Available Human locomotion is a rhythmic task in which patterns of muscle activity are modulated by state-dependent feedback to accommodate perturbations. Two popular theories have been proposed for the underlying embodiment of phase in the human pattern generator: a time-dependent internal representation or a time-invariant feedback representation (i.e., reflex mechanisms. In either case the neuromuscular system must update or represent the phase of locomotor patterns based on the system state, which can include measurements of hundreds of variables. However, a much simpler representation of phase has emerged in recent designs for legged robots, which control joint patterns as functions of a single monotonic mechanical variable, termed a phase variable. We propose that human joint patterns may similarly depend on a physical phase variable, specifically the heel-to-toe movement of the Center of Pressure under the foot. We found that when the ankle is unexpectedly rotated to a position it would have encountered later in the step, the Center of Pressure also shifts forward to the corresponding later position, and the remaining portion of the gait pattern ensues. This phase shift suggests that the progression of the stance ankle is controlled by a biomechanical phase variable, motivating future investigations of phase variables in human locomotor control.

  16. The time course of phase correction: A kinematic investigation of motor adjustment to timing perturbations during sensorimotor synchronization

    Science.gov (United States)

    Hove, Michael J.; Balasubramaniam, Ramesh; Keller, Peter E.

    2014-01-01

    Synchronizing movements with a beat requires rapid compensation for timing errors. The phase-correction response (PCR) has been studied extensively in finger tapping by shifting a metronome onset and measuring the adjustment of the following tap time. How the response unfolds during the subsequent tap cycle remains unknown. Using motion capture, we examined finger kinematics during the PCR. Participants tapped with a metronome containing phase perturbations. They tapped in ‘legato’ and ‘staccato’ style at various tempi, which altered the timing of the constituent movement stages (dwell at the surface, extension, flexion). After a phase perturbation, tapping kinematics changed compared to baseline, and the PCR was distributed differently across movement stages. In staccato tapping, the PCR trajectory changed primarily during finger extension across tempi. In legato tapping, at fast tempi the PCR occurred primarily during extension, whereas at slow tempi most phase correction was already completed during dwell. Across conditions, timing adjustments occurred primarily 100-250 ms into the following tap cycle. The change in movement around 100 ms represents the time to integrate information into an already planned movement and the rapidity suggests a subcortical route. PMID:25151103

  17. Automatic Bolus Tracking Versus Fixed Time-Delay Technique in Biphasic Multidetector Computed Tomography of the Abdomen

    International Nuclear Information System (INIS)

    Adibi, Atoosa; Shahbazi, Ali

    2014-01-01

    Bolus tracking can individualize time delay for the start of scans in spiral computed tomography (CT). We compared automatic bolus tracking method with fixed time-delay technique in biphasic contrast enhancement during multidetector CT of abdomen. Adult patients referred for spiral CT of the abdomen were randomized into two groups; in group 1, the arterial and portal phases of spiral scans were started 25 s and 55 s after the start of contrast material administration; in group 2, using the automatic bolus tracking software, repetitive monitoring scans were performed within the lumen of the descending aorta as the region of interest with the threshold of starting the diagnostic scans as 60 HU. The contrast enhancement of the aorta, liver, and spleen were compared between the groups. Forty-eight patients (23 males, 25 females, mean age=56.4±13.5 years) were included. The contrast enhancement of the aorta, liver, and spleen at the arterial phase was similar between the two groups (P>0.05). Regarding the portal phase, the aorta and spleen were more enhanced in the bolus-tracking group (P<0.001). The bolus tracking provided more homogeneous contrast enhancement among different patients than the fixed time-delay technique in the liver at portal phase, but not at the arterial phase. The automatic bolus-tracking method, results in higher contrast enhancement of the aorta and spleen at the portal phase, but has no effect on liver enhancement. However, bolus tracking is associated with reduced variability for liver enhancement among different patients

  18. Start-up processes’ efficiency of turbine jet engines

    Directory of Open Access Journals (Sweden)

    Jankowski Antoni

    2016-12-01

    Full Text Available The paper presents diagnoses of example start-up processes of drive units built in military aircraft operated in the Dęblin's “School of Eaglets” during the flight. The significance of this process is very important, especially from the point of view of flight safety, especially as it concerns the training aircraft, on which officer cadets-candidates for pilots are trained. The diagnosis of the start-up process was conducted using data from on-board flight recorders recorded during a flight training, whose aim was an emergency launch of particular drive units, and with the help of the so-called phase mapping of the selected operating parameters of the particular flight drive systems. The standard diagram of typical start-up systems was shown, while presenting their base subassemblies. At the end, the obtained results and the main problems that need intervention were commented, as well as further preventive activities were proposed.

  19. Start-up and operation of Laguna Verde-2

    International Nuclear Information System (INIS)

    Torres Ramirez, J.F.

    1996-01-01

    The 665 MWe Laguna Verde-2 nuclear generating unit was accepted into commercial operation on April 10, 1995. The boiling water reactor plant by General Electric (GE) was first synchronized with the grid on November 11, 1994. Laguna Verde-2 is identical with Laguna Verde-1 on the same site. That unit had gone critical for the first time in November 1988 and had first been synchronized with the power grid on April 13, 1989. Commercial operation of Laguna Verde-1 had been started on July 29, 1990. Mexico's only nuclear power plant had been built 70 km north of Veracruz on the east coast and had been scheduled to start operation in 1976. As the Mexican nuclear power program was reduced, the scheduled commissioning dates suffered more and more delays. In the full of 1987, the investigation by the Operational Safety Review Team (Osart) of the International Atomic Energy Agency (IAEA) had indicated that the safety requirements of installations and equpiment were met, and that the whole plant was well prepared for fueling. In mid-1988, the Mexican Government had issued the permit to fuel the Laguna Verde-1 reactor. The contract to build the two units had been awarded in 1972/73. No other nuclear power plants are currently under construction or in the planning phase in Mexico. (orig.) [de

  20. Successful hydraulic strategies to start up OLAND sequencing batch reactors at lab scale.

    Science.gov (United States)

    Schaubroeck, Thomas; Bagchi, Samik; De Clippeleir, Haydée; Carballa, Marta; Verstraete, Willy; Vlaeminck, Siegfried E

    2012-05-01

    Oxygen-limited autotrophic nitrification/denitrification (OLAND) is a one-stage combination of partial nitritation and anammox, which can have a challenging process start-up. In this study, start-up strategies were tested for sequencing batch reactors (SBR), varying hydraulic parameters, i.e. volumetric exchange ratio (VER) and feeding regime, and salinity. Two sequential tests with two parallel SBR were performed, and stable removal rates > 0.4 g N l(-1) day(-1) with minimal nitrite and nitrate accumulation were considered a successful start-up. SBR A and B were operated at 50% VER with 3 g NaCl l(-1) in the influent, and the influent was fed over 8% and 82% of the cycle time respectively. SBR B started up in 24 days, but SBR A achieved no start-up in 39 days. SBR C and D were fed over 65% of the cycle time at 25% VER, and salt was added only to the influent of SBR D (5 g NaCl l(-1)). Start-up of both SBR C and D was successful in 9 and 32 days respectively. Reactor D developed a higher proportion of small aggregates (0.10-0.25 mm), with a high nitritation to anammox rate ratio, likely the cause of the observed nitrite accumulation. The latter was overcome by temporarily including an anoxic period at the end of the reaction phase. All systems achieved granulation and similar biomass-specific nitrogen removal rates (141-220 mg N g(-1) VSS day(-1)). FISH revealed a close juxtapositioning of aerobic and anoxic ammonium-oxidizing bacteria (AerAOB and AnAOB), also in small aggregates. DGGE showed that AerAOB communities had a lower evenness than Planctomycetes communities. A higher richness of the latter seemed to be correlated with better reactor performance. Overall, the fast start-up of SBR B, C and D suggests that stable hydraulic conditions are beneficial for OLAND while increased salinity at the tested levels is not needed for good reactor performance. © 2012 The Authors. Microbial Biotechnology © 2012 Society for Applied Microbiology and Blackwell Publishing

  1. How to Start Growing Beef Calves on Feed

    OpenAIRE

    ZoBell, Dale R

    2003-01-01

    Starting calves on feed takes time and effort because of the stress young calves are susceptible to at this point in their lives. The reduction of stress will result in calves consuming more feed, thus remaining healthier. To successfully start calves on feed, dry matter intake must be maximized while minimizing health problems. The following is a 5-step applied method for starting calves on a silage-based ration.

  2. Unconventional Topological Phase Transition in Two-Dimensional Systems with Space-Time Inversion Symmetry

    Science.gov (United States)

    Ahn, Junyeong; Yang, Bohm-Jung

    2017-04-01

    We study a topological phase transition between a normal insulator and a quantum spin Hall insulator in two-dimensional (2D) systems with time-reversal and twofold rotation symmetries. Contrary to the case of ordinary time-reversal invariant systems, where a direct transition between two insulators is generally predicted, we find that the topological phase transition in systems with an additional twofold rotation symmetry is mediated by an emergent stable 2D Weyl semimetal phase between two insulators. Here the central role is played by the so-called space-time inversion symmetry, the combination of time-reversal and twofold rotation symmetries, which guarantees the quantization of the Berry phase around a 2D Weyl point even in the presence of strong spin-orbit coupling. Pair creation and pair annihilation of Weyl points accompanying partner exchange between different pairs induces a jump of a 2D Z2 topological invariant leading to a topological phase transition. According to our theory, the topological phase transition in HgTe /CdTe quantum well structure is mediated by a stable 2D Weyl semimetal phase because the quantum well, lacking inversion symmetry intrinsically, has twofold rotation about the growth direction. Namely, the HgTe /CdTe quantum well can show 2D Weyl semimetallic behavior within a small but finite interval in the thickness of HgTe layers between a normal insulator and a quantum spin Hall insulator. We also propose that few-layer black phosphorus under perpendicular electric field is another candidate system to observe the unconventional topological phase transition mechanism accompanied by the emerging 2D Weyl semimetal phase protected by space-time inversion symmetry.

  3. Loviisa starts low-level operating waste disposal in 1997

    International Nuclear Information System (INIS)

    Snellman, J.

    1996-01-01

    At an early stage Imatran Voima Oy (IVO) decided to construct a waste repository for Loviisa NPP. The suitability of the power plant site for final disposal of low- and intermediate- level operating waste was studied. In the site report in 1982 the plant site was found to be geologically suitable and economically feasible for construction. The necessary preparations started in 1992. The repository will be constructed in three phases. The first phase will cover the transport tunnel, construction of one maintenance waste tunnel and the excavation of another maintenance waste tunnel together with a hall for solidified wastes. This phase will be finished by the end of 1996. During the second phase in the beginning of next century the remaining already excavated rooms will be furnished. Finally in the third phase the repository will be extended for the decommissioning waste somewhere around years 2020-2025. (3 figs., 1 tab.)

  4. CwicStart - a proof-of-concept client for the CEOSWGISS Integrated Catalog (CWIC)

    Science.gov (United States)

    Newman, D. J.; Mitchell, A. E.

    2012-12-01

    Keywords - Earth Science, data discovery, agile development, ruby on rails, catalog, OGC Audience - Earth Science application developers What is CwicStart CwicStart is a prototypical earth science data discovery web application designed, developed and hosted by NASA's Earth Observing System (EOS) Clearinghouse (ECHO). CwicStart searches the CEOS WGISS Integrated Catalog (CWIC) to provide users with dataset and granule level metadata from sources as diverse as NASA, NOAA, INPE and AOE. CwicStart demonstrates the ease of which it is possible to stand up a functioning client against the CWIC. From start to finish, CwicStart was designed, developed and deployed in one month. Built from OGC getCapabilities document of CWIC The CwicStart application takes the OGC getCapabilities (http://www.opengeospatial.org/standards/is) document describing CWIC, as it's starting point for providing a user interface suitable for interrogating CWIC. Consequently, it can allow the user to constrain their search by the following criteria, - Generic search terms - Spatial bounding box - Start date/time and end date/time - ISO-queryable key-value pairs User Interface inspired by Reverb ECHO's state-of-the-art earth science discovery tool, Reverb (http://reverb.echo.nasa.gov) was used as a guideline for the user interface components of CwicStart. It incorporates OpenLayers to provide point-and-click spatial constraint specification and calendar input for temporal constraints. Discovery involves two phases: dataset discovery and granule discovery with full pagination support for large results sets. CwicStart supports 'graceful degradation' of support for multiple browsers and accessibility requirements. Implemented in Ruby on Rails for Agile Development CwicStart is implemented in Ruby on Rails, a dynamic, rapid development language and environment that facilitates Agile development and is resilient to changing requirements. Using an Agile development methodology ECHO was able to stand up the

  5. A novel induction motor starting method using superconduction

    International Nuclear Information System (INIS)

    Silva, F.B.B.; Orlando, M.T.D.; Fardin, J.F.; Simonetti, D.S.; Baldan, C.A.

    2014-01-01

    Highlights: • Alternative method for starting up induction motor. • Based on using a high-temperature superconductor. • A prototype of the limiter was constructed with a 2G-YBCO tape. • Prototype was tested with a 55-kW industrial induction motor in a 440-V/60-Hz. • Offers reduced current waveform distortion compared to the soft starter method. - Abstract: In this paper, an alternative method for starting up induction motors is proposed, taking into account experimental measurements. The new starting current limitation method is based on using a high-temperature superconductor. A prototype of the superconducting starting current limiter was constructed with a commercially available second-generation high-temperature superconductor YBCO tape, and this was tested with a 55-kW industrial induction motor in a 440-V/60-Hz three-phase power grid. Performance evaluations of the superconducting limiter method (applied to startup of the induction motor) were performed and were compared with a direct-on-line starter and an electronic soft starter. In addition, a computational model was developed and used for electromagnetic torque analysis of the system. As significant characteristics, our method offers the ability to limit the starting current of the induction motor with greater electromagnetic torque, reduced current waveform distortion and therefore lower harmonic pollution during startup when compared to the soft starter method

  6. A novel induction motor starting method using superconduction

    Energy Technology Data Exchange (ETDEWEB)

    Silva, F.B.B., E-mail: flaviobarcelos@ifes.edu.br [Ifes – Federal Institute of Espírito Santo, Dept. of Industrial Automation, Serra, ES 29173087 (Brazil); UFES – Federal University of Espírito Santo, Dept. of Electrical Engineering, Vitória, ES (Brazil); Orlando, M.T.D. [UFES – Federal University of Espírito Santo, Dept. of Physics, Vitória, ES (Brazil); Fardin, J.F.; Simonetti, D.S. [UFES – Federal University of Espírito Santo, Dept. of Electrical Engineering, Vitória, ES (Brazil); Baldan, C.A. [EEL/USP – Engineering School from Lorena/University of São Paulo, SP (Brazil)

    2014-12-15

    Highlights: • Alternative method for starting up induction motor. • Based on using a high-temperature superconductor. • A prototype of the limiter was constructed with a 2G-YBCO tape. • Prototype was tested with a 55-kW industrial induction motor in a 440-V/60-Hz. • Offers reduced current waveform distortion compared to the soft starter method. - Abstract: In this paper, an alternative method for starting up induction motors is proposed, taking into account experimental measurements. The new starting current limitation method is based on using a high-temperature superconductor. A prototype of the superconducting starting current limiter was constructed with a commercially available second-generation high-temperature superconductor YBCO tape, and this was tested with a 55-kW industrial induction motor in a 440-V/60-Hz three-phase power grid. Performance evaluations of the superconducting limiter method (applied to startup of the induction motor) were performed and were compared with a direct-on-line starter and an electronic soft starter. In addition, a computational model was developed and used for electromagnetic torque analysis of the system. As significant characteristics, our method offers the ability to limit the starting current of the induction motor with greater electromagnetic torque, reduced current waveform distortion and therefore lower harmonic pollution during startup when compared to the soft starter method.

  7. Effect of different knee starting angles on intersegmental coordination and performance in vertical jumps.

    Science.gov (United States)

    Gheller, Rodrigo G; Dal Pupo, Juliano; Ache-Dias, Jonathan; Detanico, Daniele; Padulo, Johnny; dos Santos, Saray G

    2015-08-01

    This study aimed to analyze the effect of different knee starting angles on jump performance, kinetic parameters, and intersegmental coupling coordination during a squat jump (SJ) and a countermovement jump (CMJ). Twenty male volleyball and basketball players volunteered to participate in this study. The CMJ was performed with knee flexion at the end of the countermovement phase smaller than 90° (CMJ(90)), and in a preferred position (CMJ(PREF)), while the SJ was performed from a knee angle of 70° (SJ(70)), 90° (SJ(90)), 110° (SJ(110)), and in a preferred position (SJ(PREF)). The best jump performance was observed in jumps that started from a higher squat depth (CMJ(90). Analysis of continuous relative phase showed that thigh-trunk coupling was more in-phase in the jumps (CMJ and SJ) performed with a higher squat depth, while the leg-thigh coupling was more in-phase in the CMJ(>90) and SJ(PREF). Jumping from a position with knees more flexed seems to be the best strategy to achieve the best performance. Intersegmental coordination and jump performance (CMJ and SJ) were affected by different knee starting angles. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. A time-reversal invariant topological phase at the surface of a 3D topological insulator

    International Nuclear Information System (INIS)

    Bonderson, Parsa; Nayak, Chetan; Qi, Xiao-Liang

    2013-01-01

    A 3D fermionic topological insulator has a gapless Dirac surface state protected by time-reversal symmetry and charge conservation symmetry. The surface state can be gapped by introducing ferromagnetism to break time-reversal symmetry, introducing superconductivity to break charge conservation, or entering a topological phase. In this paper, we construct a minimal gapped topological phase that preserves both time-reversal and charge conservation symmetries and supports Ising-type non-Abelian anyons. This phase can be understood heuristically as emerging from a surface s-wave superconducting state via the condensation of eight-vortex composites. The topological phase inherits vortices supporting Majorana zero modes from the surface superconducting state. However, since it is time-reversal invariant, the surface topological phase is a distinct phase from the Ising topological phase, which can be viewed as a quantum-disordered spin-polarized p x + ip y superconductor. We discuss the anyon model of this topological phase and the manner in which time-reversal symmetry is realized in it. We also study the interfaces between the topological state and other surface gapped phases. (paper)

  9. A bulk queueing system under N-policy with bilevel service delay discipline and start-up time

    Directory of Open Access Journals (Sweden)

    David C. R. Muh

    1993-01-01

    Full Text Available The author studies the queueing process in a single-server, bulk arrival and batch service queueing system with a compound Poisson input, bilevel service delay discipline, start-up time, and a fixed accumulation level with control operating policy. It is assumed that when the queue length falls below a predefined level r(≥1, the system, with server capacity R, immediately stops service until the queue length reaches or exceeds the second predefined accumulation level N(≥r. Two cases, with N≤R and N≥R, are studied.

  10. Ideal Timing of Starting Weight-Bearing After Calcaneal Insufficiency Fracture: A Case Report and Review of the Literature

    OpenAIRE

    Imamura; Mochizuki; Kawakami; Momohara

    2016-01-01

    Introduction Criteria for starting weight-bearing on the heel with a symptomatic calcaneal insufficiency fracture have not yet been reported. Case Presentation We describe a rare case of a 52-year-old woman with a calcaneal insufficiency fracture who sustained a second ipsilateral calcaneal insufficiency fracture within a short time span. The initial fracture was not evident radiographically, but was detected using magnetic resona...

  11. On Stability of Natural-circulation-cooled Boiling Water Reactors during Start-up (Experimental Results)

    International Nuclear Information System (INIS)

    Manera, A.; Van der Hagen, T.H.J.J.

    2002-01-01

    The characteristics of flashing-induced instabilities, which are of importance during the start-up phase of natural-circulation Boiling Water Reactors (BWRs), are studied. Experiments at typical start-up conditions (low power and low pressure) are carried out on a steam/water natural circulation loop. The mechanism of flashing-induced instability is analyzed in detail and it is found that non-equilibrium between phases and enthalpy transport plays an important role in the instability process. Pressure and steam volume in the steam dome are found to have a stabilizing effect. The main characteristics of the instabilities have been analyzed. (authors)

  12. Start-up simulations of the PULSAR pulsed tokamak reactor

    International Nuclear Information System (INIS)

    Werley, K.A.; Bathke, C.G.

    1993-01-01

    Start-up conditions are examined for a pulsed tokamak reactor that uses only inductively driven plasma current (and bootstrap current). A zero-dimensional (profile-averaged) model containing plasma power and particle balance equations is used to study several aspects of plasma start-up, including: (1) optimization of the start-up pathway; (2) tradeoffs of auxiliary start-up heating power versus start-up time; (3) volt-second consumption; (4) thermal stability of the operating point; (5) estimates of the diverter heat flux and temperature during the start-up transient; (6) the sensitivity of the available operating space to allowed values of the H confinement factor; and (7) partial-power operations

  13. Time domain spectral phase encoding/DPSK data modulation using single phase modulator for OCDMA application.

    Science.gov (United States)

    Wang, Xu; Gao, Zhensen; Kataoka, Nobuyuki; Wada, Naoya

    2010-05-10

    A novel scheme using single phase modulator for simultaneous time domain spectral phase encoding (SPE) signal generation and DPSK data modulation is proposed and experimentally demonstrated. Array- Waveguide-Grating and Variable-Bandwidth-Spectrum-Shaper based devices can be used for decoding the signal directly in spectral domain. The effects of fiber dispersion, light pulse width and timing error on the coding performance have been investigated by simulation and verified in experiment. In the experiment, SPE signal with 8-chip, 20GHz/chip optical code patterns has been generated and modulated with 2.5 Gbps DPSK data using single modulator. Transmission of the 2.5 Gbps data over 34km fiber with BEROCDMA) and secure optical communication applications. (c) 2010 Optical Society of America.

  14. Real-time quantitative phase reconstruction in off-axis digital holography using multiplexing.

    Science.gov (United States)

    Girshovitz, Pinhas; Shaked, Natan T

    2014-04-15

    We present a new approach for obtaining significant speedup in the digital processing of extracting unwrapped phase profiles from off-axis digital holograms. The new technique digitally multiplexes two orthogonal off-axis holograms, where the digital reconstruction, including spatial filtering and two-dimensional phase unwrapping on a decreased number of pixels, can be performed on both holograms together, without redundant operations. Using this technique, we were able to reconstruct, for the first time to our knowledge, unwrapped phase profiles from off-axis holograms with 1 megapixel in more than 30 frames per second using a standard single-core personal computer on a MATLAB platform, without using graphic-processing-unit programming or parallel computing. This new technique is important for real-time quantitative visualization and measurements of highly dynamic samples and is applicable for a wide range of applications, including rapid biological cell imaging and real-time nondestructive testing. After comparing the speedups obtained by the new technique for holograms of various sizes, we present experimental results of real-time quantitative phase visualization of cells flowing rapidly through a microchannel.

  15. De-escalatory confidence-building measures after START

    International Nuclear Information System (INIS)

    Stockton, P.N.

    1992-01-01

    The very notion of examining de-escalatory CBMs in the context of the START negotiations appears odd. Given the immense progress in US-Soviet relations, of which the proposed START agreement is emblematic, the risk of the two nations stumbling to the brink of war seems increasingly remote. Why bother analyzing CBMs designed to help resolve such an improbable event? The obvious answer is that relations between the US and the Soviet Union - or whatever array of nations succeed it - could take an unforeseeable turn for the worse. Once ratified, the START agreement is supposed to remain in force for seven years, more than enough time for political tensions to return with a vengeance. This suggests a more prudent question: if our two nations do stumble to the brink of war, will the START agreement affect the prospect of de-escalatory CBMs? And if the US and Soviet Union pursue deeper force-reductions in a follow-on START II agreement, could that agreement be designed to facilitate more effective de-escalatory measures? This paper sets the stage for addressing such questions by outlining the START agreement and offering a brief overview of how START might affect the prospects for CBMs. Then, after examining some specific CBM proposals in light of START, an analysis will be made of the de-escalatory problems and opportunities that a Start II treaty might create

  16. The role of relationships in start-up development

    DEFF Research Database (Denmark)

    Mattsson, Jan; Helmersson, Helge; Standing, Craig

    2017-01-01

    Relationships are important in the business start-up phase for a variety of reasons. Internal relationships can support knowledge exchange that determines the business model development and external relationships can facilitate a wide range of opportunities, support and insights. The paper explains...... the key relationships experienced by the founding team of a recently formed Swedish digital trading platform. Data were gathered through a self-reporting diary approach based on the Critical Incident Technique format and texts were analysed by the Pertex text-analytic software. The findings explain how...... important relationships were formed during the initial start-up period targeting international expansion. Interaction with early adopters enabled a rapid evolution of the business platform with the aim to build a community of users to support development....

  17. Kalman filters for real-time magnetic island phase tracking

    International Nuclear Information System (INIS)

    Borgers, D.P.; Lauret, M.; Baar, M.R. de

    2013-01-01

    Highlights: • We propose two Kalman filters for tracking of NTMs on ASDEX Upgrade. • The Kalman filters can track NTMs in a much larger frequency range than PLLs. • The filters are tested on synthetic and experimental data from TEXTOR and TCV. • We conclude that the unscented Kalman filter can be useful for NTM control. -- Abstract: For control of neoclassical tearing modes (NTMs) and the resulting rotating magnetic islands in tokamak plasmas, the frequency and phase of the magnetic islands need to be accurately tracked in real-time. In previous experiments on TEXTOR, this was achieved using a phase-locked loop (PLL). For ASDEX Upgrade however, the desired frequency range in which the islands are to be tracked (100 Hz–10 kHz) is much larger than is possible with a PLL. In this contribution, an extended Kalman filter (EKF) and an unscented Kalman filter (UKF) are proposed for real-time frequency, phase and amplitude tracking of sinusoidal signals, based on noisy measurements. Compared to PLLs, the EKF and UKF are able to track sinusoidal signals in a much larger frequency range. The filters are applied on synthetic data and on experimental data from the TEXTOR and TCV tokamaks, from which we conclude that the UKF can be useful for real-time control of magnetic islands on ASDEX Upgrade

  18. Kalman filters for real-time magnetic island phase tracking

    Energy Technology Data Exchange (ETDEWEB)

    Borgers, D.P. [Hybrid and Networked Systems, Department of Mechanical Engineering – Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven (Netherlands); Lauret, M., E-mail: M.Lauret@tue.nl [FOM Institute DIFFER – Dutch Institute for Fundamental Energy Research, Association EURATOM-FOM, Trilateral Euregio Cluster, P.O. Box 1207, Nieuwegein (Netherlands); Control Systems Technology, Department of Mechanical Engineering – Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven (Netherlands); Baar, M.R. de [FOM Institute DIFFER – Dutch Institute for Fundamental Energy Research, Association EURATOM-FOM, Trilateral Euregio Cluster, P.O. Box 1207, Nieuwegein (Netherlands); Control Systems Technology, Department of Mechanical Engineering – Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven (Netherlands)

    2013-11-15

    Highlights: • We propose two Kalman filters for tracking of NTMs on ASDEX Upgrade. • The Kalman filters can track NTMs in a much larger frequency range than PLLs. • The filters are tested on synthetic and experimental data from TEXTOR and TCV. • We conclude that the unscented Kalman filter can be useful for NTM control. -- Abstract: For control of neoclassical tearing modes (NTMs) and the resulting rotating magnetic islands in tokamak plasmas, the frequency and phase of the magnetic islands need to be accurately tracked in real-time. In previous experiments on TEXTOR, this was achieved using a phase-locked loop (PLL). For ASDEX Upgrade however, the desired frequency range in which the islands are to be tracked (100 Hz–10 kHz) is much larger than is possible with a PLL. In this contribution, an extended Kalman filter (EKF) and an unscented Kalman filter (UKF) are proposed for real-time frequency, phase and amplitude tracking of sinusoidal signals, based on noisy measurements. Compared to PLLs, the EKF and UKF are able to track sinusoidal signals in a much larger frequency range. The filters are applied on synthetic data and on experimental data from the TEXTOR and TCV tokamaks, from which we conclude that the UKF can be useful for real-time control of magnetic islands on ASDEX Upgrade.

  19. Gendered career considerations consolidate from the start of medical education

    NARCIS (Netherlands)

    Alers, M.; Verdonk, P.; Bor, H.; Hamberg, K.; Lagro-Janssen, A.

    2014-01-01

    OBJECTIVE: To explore changes in specialty preferences and work-related topics during the theoretical phase of Dutch medical education and the role of gender. METHODS: A cohort of medical students at Radboudumc, the Netherlands, was surveyed at start (N=612, 69.1% female) and after three years

  20. Structural formation of aluminide phases on titanium alloy during annealing

    International Nuclear Information System (INIS)

    Mamaeva, A.A.; Romankov, S.E.; Sagdoldina, Zh.

    2006-01-01

    Full text: The aluminum layer on the surface of titanium alloy has been formed by thermal deposition. The structural formation of aluminide phases on the surface has been studied. The sequence of structural transformations at the Ti/Al interface is limited by the reaction temperature and time. The sequence of aluminide phase formation is occurred in compliance with Ti-Al equilibrium phase diagram. At the initial stages at the Ti/Al interface the Al3Ti alloy starts forming as a result of interdiffusion, and gradually the whole aluminum films is spent on the formation of this layer. The Al3Ti layer decomposes with the increase of temperature (>600C). At 800C the two-phase (Ti3Al+TiAl) layer is formed on the titanium surface. The TiAl compound is unstable and later on with the increase of the exposure time at 800C gradually transforms into the Ti3Al. The chain of these successive transformations leads to the formation of the continuous homogeneous layer consisting of the Ti3Al compound on the surface. At temperatures exceeding the allotropic transformation temperature (>900C) the Ti3Al compound starts decomposing. All structural changes taking place at the Ti/Al interface are accompanied by considerable changes in micro hardness. The structure of initial substrate influences on kinetics of phase transformation and microstructure development. (author)

  1. Dynamical quantum phase transitions: a review

    Science.gov (United States)

    Heyl, Markus

    2018-05-01

    Quantum theory provides an extensive framework for the description of the equilibrium properties of quantum matter. Yet experiments in quantum simulators have now opened up a route towards the generation of quantum states beyond this equilibrium paradigm. While these states promise to show properties not constrained by equilibrium principles, such as the equal a priori probability of the microcanonical ensemble, identifying the general properties of nonequilibrium quantum dynamics remains a major challenge, especially in view of the lack of conventional concepts such as free energies. The theory of dynamical quantum phase transitions attempts to identify such general principles by lifting the concept of phase transitions to coherent quantum real-time evolution. This review provides a pedagogical introduction to this field. Starting from the general setting of nonequilibrium dynamics in closed quantum many-body systems, we give the definition of dynamical quantum phase transitions as phase transitions in time with physical quantities becoming nonanalytic at critical times. We summarize the achieved theoretical advances as well as the first experimental observations, and furthermore provide an outlook to major open questions as well as future directions of research.

  2. Dynamical quantum phase transitions: a review.

    Science.gov (United States)

    Heyl, Markus

    2018-05-01

    Quantum theory provides an extensive framework for the description of the equilibrium properties of quantum matter. Yet experiments in quantum simulators have now opened up a route towards the generation of quantum states beyond this equilibrium paradigm. While these states promise to show properties not constrained by equilibrium principles, such as the equal a priori probability of the microcanonical ensemble, identifying the general properties of nonequilibrium quantum dynamics remains a major challenge, especially in view of the lack of conventional concepts such as free energies. The theory of dynamical quantum phase transitions attempts to identify such general principles by lifting the concept of phase transitions to coherent quantum real-time evolution. This review provides a pedagogical introduction to this field. Starting from the general setting of nonequilibrium dynamics in closed quantum many-body systems, we give the definition of dynamical quantum phase transitions as phase transitions in time with physical quantities becoming nonanalytic at critical times. We summarize the achieved theoretical advances as well as the first experimental observations, and furthermore provide an outlook to major open questions as well as future directions of research.

  3. Measurement of time delay for a prospectively gated CT simulator.

    Science.gov (United States)

    Goharian, M; Khan, R F H

    2010-04-01

    For the management of mobile tumors, respiratory gating is the ideal option, both during imaging and during therapy. The major advantage of respiratory gating during imaging is that it is possible to create a single artifact-free CT data-set during a selected phase of the patient's breathing cycle. The purpose of the present work is to present a simple technique to measure the time delay during acquisition of a prospectively gated CT. The time delay of a Philips Brilliance BigBore (Philips Medical Systems, Madison, WI) scanner attached to a Varian Real-Time Position Management (RPM) system (Varian Medical Systems, Palo Alto, CA) was measured. Two methods were used to measure the CT time delay: using a motion phantom and using a recorded data file from the RPM system. In the first technique, a rotating wheel phantom was altered by placing two plastic balls on its axis and rim, respectively. For a desired gate, the relative positions of the balls were measured from the acquired CT data and converted into corresponding phases. Phase difference was calculated between the measured phases and the desired phases. Using period of motion, the phase difference was converted into time delay. The Varian RPM system provides an external breathing signal; it also records transistor-transistor logic (TTL) 'X-Ray ON' status signal from the CT scanner in a text file. The TTL 'X-Ray ON' indicates the start of CT image acquisition. Thus, knowledge of the start time of CT acquisition, combined with the real-time phase and amplitude data from the external respiratory signal, provides time-stamping of all images in an axial CT scan. The TTL signal with time-stamp was used to calculate when (during the breathing cycle) a slice was recorded. Using the two approaches, the time delay between the prospective gating signal and CT simulator has been determined to be 367 +/- 40 ms. The delay requires corrections both at image acquisition and while setting gates for the treatment delivery

  4. Ab initio quantum-enhanced optical phase estimation using real-time feedback control

    DEFF Research Database (Denmark)

    Berni, Adriano; Gehring, Tobias; Nielsen, Bo Melholt

    2015-01-01

    of a quantum-enhanced and fully deterministic ab initio phase estimation protocol based on real-time feedback control. Using robust squeezed states of light combined with a real-time Bayesian adaptive estimation algorithm, we demonstrate deterministic phase estimation with a precision beyond the quantum shot...... noise limit. The demonstrated protocol opens up new opportunities for quantum microscopy, quantum metrology and quantum information processing....

  5. Sex Differences in Countermovement Jump Phase Characteristics

    Directory of Open Access Journals (Sweden)

    John J. McMahon

    2017-01-01

    Full Text Available The countermovement jump (CMJ is commonly used to explore sex differences in neuromuscular function, but previous studies have only reported gross CMJ measures or have partly examined CMJ phase characteristics. The purpose of this study was to explore differences in CMJ phase characteristics between male and female athletes by comparing the force-, power-, velocity-, and displacement-time curves throughout the entire CMJ, in addition to gross measures. Fourteen men and fourteen women performed three CMJs on a force platform from which a range of kinetic and kinematic variables were calculated via forward dynamics. Jump height (JH, reactive strength index modified, relative peak concentric power, and eccentric and concentric displacement, velocity, and relative impulse were all greater for men (g = 0.58–1.79. Relative force-time curves were similar between sexes, but relative power-, velocity-, and displacement-time curves were greater for men at 90%–95% (immediately before and after peak power, 47%–54% (start of eccentric phase and 85%–100% (latter half of concentric phase, and 65%–87% (bottom of countermovement and initial concentric phase of normalized jump time, respectively. The CMJ distinguished between sexes, with men demonstrating greater JH through applying a larger concentric impulse and, thus, achieving greater velocity throughout most of the concentric phase, including take-off.

  6. Design of Controller for Reducing In-Rush Current of Single-Phase Induction Motor

    Energy Technology Data Exchange (ETDEWEB)

    Park, Su Kang; Baek, Hyung Lae; Lee, Sang Il [Chosun University, Kwangju (Korea)

    2001-05-01

    During an AC motor's start-up accelerating period, a large amount of current is required to reach to the rating speed. This is called in-rush current. This peak in-rush current can be more than about several times the operating or steady-state current in the full load rating of the motor. In-rush current is present in both and electronic ballasts. The main area of concern is the tripping of circuit breaker and fuses which can affect electrical system components From this, we can see that the electrical power controllers will be rather concerned, since they have to supply the actual current necessary to start the motor. This paper presents a new method to reducing in-rush current and energy saving of the single-phase induction motor used in air-conditioner. It can be obtained that proposed system is low cost and small size as compared with other controller. Experiments are focused on a capacitor starting single-phase induction motor. The optimal power saving and in-rush current limiting by phase angle control are verified by experimental results. Also, auxiliary winding was controlled by electronic starting switch. (author). 10 refs., 13 figs., 2 tabs.

  7. FPGA-based real-time phase measuring profilometry algorithm design and implementation

    Science.gov (United States)

    Zhan, Guomin; Tang, Hongwei; Zhong, Kai; Li, Zhongwei; Shi, Yusheng

    2016-11-01

    Phase measuring profilometry (PMP) has been widely used in many fields, like Computer Aided Verification (CAV), Flexible Manufacturing System (FMS) et al. High frame-rate (HFR) real-time vision-based feedback control will be a common demands in near future. However, the instruction time delay in the computer caused by numerous repetitive operations greatly limit the efficiency of data processing. FPGA has the advantages of pipeline architecture and parallel execution, and it fit for handling PMP algorithm. In this paper, we design a fully pipelined hardware architecture for PMP. The functions of hardware architecture includes rectification, phase calculation, phase shifting, and stereo matching. The experiment verified the performance of this method, and the factors that may influence the computation accuracy was analyzed.

  8. Versatile real-time interferometer phase-detection system using high-speed digital techniques

    International Nuclear Information System (INIS)

    Mendell, D.S.; Willett, G.W.

    1977-01-01

    This paper describes the basic design and philosophy of a versatile real-time interferometer phase-detection system to be used on the 2XIIB and TMX magnetic-fusion experiments at Lawrence Livermore Laboratory. This diagnostics system is a satellite to a host computer and uses high-speed emitter-coupled logic techniques to derive data on real-time phase relationships. The system's input signals can be derived from interferometer outputs over a wide range of reference frequencies. An LSI-11 microcomputer is the interface between the high-speed phase-detection logic, buffer memory, human interaction, and host computer. Phase data on a storage CRT is immediately displayed after each experimental fusion shot. An operator can interrogate this phase data more closely from an interactive control panel, and the host computer can be simultaneously examining the system's buffer memory or arming the system for the next shot

  9. Scalar Aharonov–Bohm Phase in Ramsey Atom Interferometry under Time-Varying Potential

    Directory of Open Access Journals (Sweden)

    Atsuo Morinaga

    2016-08-01

    Full Text Available In a Ramsey atom interferometer excited by two electromagnetic fields, if atoms are under a time-varying scalar potential during the interrogation time, the phase of the Ramsey fringes shifts owing to the scalar Aharonov–Bohm effect. The phase shift was precisely examined using a Ramsey atom interferometer with a two-photon Raman transition under the second-order Zeeman potential, and a formula for the phase shift was derived. Using the derived formula, the frequency shift due to the scalar Aharonov–Bohm effect in the frequency standards utilizing the Ramsey atom interferometer was discussed.

  10. Simple flight time calibration generator in PLL technique

    International Nuclear Information System (INIS)

    Lauch, J.

    1975-01-01

    Calibration and routine check-ups of flight time measuring systems can be carried out with the aid of defined flight time calibration spectra. This paper describes a simple flight time calibration generator capable of generating such calibration spectra in the form of line spectra or of a white spectrum. The flight time of the generator is adjustable in steps from 100 to 3,200 ns. The number of calibration lines can be set to 10 or to 20, resulting in line spacings ranging from 5 to 320 ns. The stop signals are generated by a crystal oscillator, the start signals are generated by a voltage-controlled oscillator locked in a phase control circuit. The start and stop rates can be adjusted in steps. (orig.) [de

  11. Holographic cinematography of time-varying reflecting and time-varying phase objects using a Nd:YAG laser

    Science.gov (United States)

    Decker, A. J.

    1982-01-01

    The use of a Nd:YAG laser to record holographic motion pictures of time-varying reflecting objects and time-varying phase objects is discussed. Sample frames from both types of holographic motion pictures are presented. The holographic system discussed is intended for three-dimensional flow visualization of the time-varying flows that occur in jet-engine components.

  12. Errors analysis in the evaluation of particle concentration by PDA on a turbulent two-phase jet: application for cross section and transit time methods

    Science.gov (United States)

    Calvo, Esteban; García, Juan A.; García, Ignacio; Aísa, Luis A.

    2009-09-01

    Phase-Doppler anemometry (PDA) is a powerful tool for two-phase flow measurements and testing. Particle concentration and mass flux can also be evaluated using the raw particle data supplied by this technique. The calculation starts from each particle velocity, diameter, transit time data, and the total measurement time. There are two main evaluation strategies. The first one uses the probe volume effective cross section, and it is usually simplified assuming that particles follow quasi one-directional trajectories. In the text, it will be called the cross section method. The second one includes a set of methods which will be denoted as “Generalized Integral Methods” (GIM). Concentration algorithms such as the transit time method (TTM) and the integral volume method (IVM) are particular cases of the GIM. In any case, a previous calibration of the measurement volume geometry is necessary to apply the referred concentration evaluation methods. In this study, concentrations and mass fluxes both evaluated by the cross-section method and the TTM are compared. Experimental data are obtained from a particle-laden jet generated by a convergent nozzle. Errors due to trajectory dispersion, burst splitting, and multi-particle signals are discussed.

  13. Errors analysis in the evaluation of particle concentration by PDA on a turbulent two-phase jet: application for cross section and transit time methods

    Energy Technology Data Exchange (ETDEWEB)

    Calvo, Esteban; Garcia, Juan A.; Garcia, Ignacio; Aisa, Luis A. [University of Zaragoza, Area de Mecanica de Fluidos, Centro Politecnico Superior, Zaragoza (Spain)

    2009-09-15

    Phase-Doppler anemometry (PDA) is a powerful tool for two-phase flow measurements and testing. Particle concentration and mass flux can also be evaluated using the raw particle data supplied by this technique. The calculation starts from each particle velocity, diameter, transit time data, and the total measurement time. There are two main evaluation strategies. The first one uses the probe volume effective cross section, and it is usually simplified assuming that particles follow quasi one-directional trajectories. In the text, it will be called the cross section method. The second one includes a set of methods which will be denoted as ''Generalized Integral Methods'' (GIM). Concentration algorithms such as the transit time method (TTM) and the integral volume method (IVM) are particular cases of the GIM. In any case, a previous calibration of the measurement volume geometry is necessary to apply the referred concentration evaluation methods. In this study, concentrations and mass fluxes both evaluated by the cross-section method and the TTM are compared. Experimental data are obtained from a particle-laden jet generated by a convergent nozzle. Errors due to trajectory dispersion, burst splitting, and multi-particle signals are discussed. (orig.)

  14. Oscillatory phase dynamics in neural entrainment underpin illusory percepts of time.

    Science.gov (United States)

    Herrmann, Björn; Henry, Molly J; Grigutsch, Maren; Obleser, Jonas

    2013-10-02

    Neural oscillatory dynamics are a candidate mechanism to steer perception of time and temporal rate change. While oscillator models of time perception are strongly supported by behavioral evidence, a direct link to neural oscillations and oscillatory entrainment has not yet been provided. In addition, it has thus far remained unaddressed how context-induced illusory percepts of time are coded for in oscillator models of time perception. To investigate these questions, we used magnetoencephalography and examined the neural oscillatory dynamics that underpin pitch-induced illusory percepts of temporal rate change. Human participants listened to frequency-modulated sounds that varied over time in both modulation rate and pitch, and judged the direction of rate change (decrease vs increase). Our results demonstrate distinct neural mechanisms of rate perception: Modulation rate changes directly affected listeners' rate percept as well as the exact frequency of the neural oscillation. However, pitch-induced illusory rate changes were unrelated to the exact frequency of the neural responses. The rate change illusion was instead linked to changes in neural phase patterns, which allowed for single-trial decoding of percepts. That is, illusory underestimations or overestimations of perceived rate change were tightly coupled to increased intertrial phase coherence and changes in cerebro-acoustic phase lag. The results provide insight on how illusory percepts of time are coded for by neural oscillatory dynamics.

  15. Reviews/Essays: School Start Times and the Sleep-Wake Cycle of Adolescents--A Review and Critical Evaluation of Available Evidence

    Science.gov (United States)

    Kirby, Matthew; Maggi, Stefania; D'Angiulli, Amedeo

    2011-01-01

    The authors have integrated the major findings on the sleep-wake cycle and its performance correlates in adolescents. Basic research shows that lack of synchronicity between early school start times and the circadian rhythm of adolescents (and the sleep debt accumulated as a result) involves several cognitive correlates that may harm the academic…

  16. Markov transition probability-based network from time series for characterizing experimental two-phase flow

    International Nuclear Information System (INIS)

    Gao Zhong-Ke; Hu Li-Dan; Jin Ning-De

    2013-01-01

    We generate a directed weighted complex network by a method based on Markov transition probability to represent an experimental two-phase flow. We first systematically carry out gas—liquid two-phase flow experiments for measuring the time series of flow signals. Then we construct directed weighted complex networks from various time series in terms of a network generation method based on Markov transition probability. We find that the generated network inherits the main features of the time series in the network structure. In particular, the networks from time series with different dynamics exhibit distinct topological properties. Finally, we construct two-phase flow directed weighted networks from experimental signals and associate the dynamic behavior of gas-liquid two-phase flow with the topological statistics of the generated networks. The results suggest that the topological statistics of two-phase flow networks allow quantitative characterization of the dynamic flow behavior in the transitions among different gas—liquid flow patterns. (general)

  17. Stimulating at the right time: phase-specific deep brain stimulation.

    Science.gov (United States)

    Cagnan, Hayriye; Pedrosa, David; Little, Simon; Pogosyan, Alek; Cheeran, Binith; Aziz, Tipu; Green, Alexander; Fitzgerald, James; Foltynie, Thomas; Limousin, Patricia; Zrinzo, Ludvic; Hariz, Marwan; Friston, Karl J; Denison, Timothy; Brown, Peter

    2017-01-01

    SEE MOLL AND ENGEL DOI101093/AWW308 FOR A SCIENTIFIC COMMENTARY ON THIS ARTICLE: Brain regions dynamically engage and disengage with one another to execute everyday actions from movement to decision making. Pathologies such as Parkinson's disease and tremor emerge when brain regions controlling movement cannot readily decouple, compromising motor function. Here, we propose a novel stimulation strategy that selectively regulates neural synchrony through phase-specific stimulation. We demonstrate for the first time the therapeutic potential of such a stimulation strategy for the treatment of patients with pathological tremor. Symptom suppression is achieved by delivering stimulation to the ventrolateral thalamus, timed according to the patient's tremor rhythm. Sustained locking of deep brain stimulation to a particular phase of tremor afforded clinically significant tremor relief (up to 87% tremor suppression) in selected patients with essential tremor despite delivering less than half the energy of conventional high frequency stimulation. Phase-specific stimulation efficacy depended on the resonant characteristics of the underlying tremor network. Selective regulation of neural synchrony through phase-locked stimulation has the potential to both increase the efficiency of therapy and to minimize stimulation-induced side effects. © The Author (2016). Published by Oxford University Press on behalf of the Guarantors of Brain.

  18. Robotic surgery start-up with a fellow as the console surgeon

    DEFF Research Database (Denmark)

    Reinhardt, Susanne; Ifaoui, Inge Boetker; Thorup, Jorgen

    2017-01-01

    learning curve for robotic pyeloplasty will allow pediatric urology fellowship programs to be integrated in the start-up phase of a pediatric robotic program even though the case material is limited. Operative success rates were in accordance with the gold standard of open surgery....

  19. From Head Start to Sure Start: Reflections on Policy Transfer

    Science.gov (United States)

    Welshman, John

    2010-01-01

    This article uses the history of debates over the US Head Start programme (1965), Early Head Start (1994) and the UK Sure Start initiative (1998), as a window on to policy transfer. In all the three, the aim was that early intervention could offer a means of boosting children's educational attainment and of countering the wider effects of poverty…

  20. Confidence in Phase Definition for Periodicity in Genes Expression Time Series.

    Science.gov (United States)

    El Anbari, Mohammed; Fadda, Abeer; Ptitsyn, Andrey

    2015-01-01

    Circadian oscillation in baseline gene expression plays an important role in the regulation of multiple cellular processes. Most of the knowledge of circadian gene expression is based on studies measuring gene expression over time. Our ability to dissect molecular events in time is determined by the sampling frequency of such experiments. However, the real peaks of gene activity can be at any time on or between the time points at which samples are collected. Thus, some genes with a peak activity near the observation point have their phase of oscillation detected with better precision then those which peak between observation time points. Separating genes for which we can confidently identify peak activity from ambiguous genes can improve the analysis of time series gene expression. In this study we propose a new statistical method to quantify the phase confidence of circadian genes. The numerical performance of the proposed method has been tested using three real gene expression data sets.

  1. A new analytical model for conduction heating during the SAGD circulation phase

    Energy Technology Data Exchange (ETDEWEB)

    Duong, A.N. [Society of Petroleum Engineers, Canadian Section, Calgary, AB (Canada)]|[ConocoPhillips Canada Resources Corp., Calgary, AB (Canada); Tomberlin, T.A. [ConocoPhillips Canada Resources Corp., Calgary, AB (Canada); Cyrot, M. [Total E and P Canada Ltd., Calgary, AB (Canada)

    2008-10-15

    The steam assisted gravity drainage (SAGD) process has become the common procedure to recover bitumen from Alberta's oilsands. Inter-well communication must be initiated during the start-up phase of a SAGD process. The shape of an initial steam chamber that develops during the circulation phase influences the efficiency of bitumen recovery. As such, the heating conformance distributed along the horizontal wellbores must be well understood. The duration of the start-up phase varies with the characteristics of the oilsand formation and the distance between the wellbores, but it is typically a month to several months. This paper presented a newly developed analytical model that predicts the initial steam chamber. The model improves bitumen recovery efficiency by predicting the mid-point temperature front and heating efficiency of a wellpair during the SAGD circulation phase. The Excel-based model uses the exponential integral solution for radial heating in a long cylinder and superposition in space for multi-heating sources. It can predict the temperature profile if the steam temperatures or pressures are known during the circulation period. Wellbore modeling that includes any variation in distances between the wellbores is critical to both circulation time and heating conformance. This model has an advantage over numerical simulation in terms of reducing computational time and accurately modelling any variation in distance between wellbores. The results can be optimized under various operational conditions, wellbore profiles, tubing sizes and convection flow effects. This easy to use model is currently being used by ConocoPhillips Canada to optimize, predict and guide oilsands projects during the start-up phase of a SAGD process. 5 refs., 13 figs.

  2. Mortality According to CD4 Count at Start of Combination Antiretroviral Therapy Among HIV-infected Patients Followed for up to 15 Years After Start of Treatment

    DEFF Research Database (Denmark)

    May, Margaret T; Vehreschild, Jorg-Janne; Trickey, Adam

    2016-01-01

    BACKGROUND: CD4 count at start of combination antiretroviral therapy (ART) is strongly associated with short-term survival, but its association with longer-term survival is less well characterized. METHODS: We estimated mortality rates (MRs) by time since start of ART (...-4.9, 5-9.9, and ≥10 years) among patients from 18 European and North American cohorts who started ART during 1996-2001. Piecewise exponential models stratified by cohort were used to estimate crude and adjusted (for sex, age, transmission risk, period of starting ART [1996-1997, 1998-1999, 2000......-2001], and AIDS and human immunodeficiency virus type 1 RNA at baseline) mortality rate ratios (MRRs) by CD4 count at start of ART (0-49, 50-99, 100-199, 200-349, 350-499, ≥500 cells/µL) overall and separately according to time since start of ART. RESULTS: A total of 6344 of 37 496 patients died during 359 219...

  3. A chronotype comparison of South African and Dutch marathon runners: the role of scheduled race start times and effects on performance

    NARCIS (Netherlands)

    Henst, R.; Jaspers, R.T.; Roden, L.; Rae, D.

    2015-01-01

    Recently, a high prevalence of morning-types was reported among trained South African endurance athletes. Proposed explanations for this observation were that either the chronotype of these athletes is better suited to coping with the early-morning start times of endurance events in South Africa; or

  4. Time-delay-induced phase-transition to synchrony in coupled bursting neurons

    Science.gov (United States)

    Adhikari, Bhim Mani; Prasad, Awadhesh; Dhamala, Mukeshwar

    2011-06-01

    Signal transmission time delays in a network of nonlinear oscillators are known to be responsible for a variety of interesting dynamic behaviors including phase-flip transitions leading to synchrony or out of synchrony. Here, we uncover that phase-flip transitions are general phenomena and can occur in a network of coupled bursting neurons with a variety of coupling types. The transitions are marked by nonlinear changes in both temporal and phase-space characteristics of the coupled system. We demonstrate these phase-transitions with Hindmarsh-Rose and Leech-Heart interneuron models and discuss the implications of these results in understanding collective dynamics of bursting neurons in the brain.

  5. Second Harmonic 110 GHz ECH-assisted Start-up in KSTAR

    Directory of Open Access Journals (Sweden)

    Han S. H.

    2012-09-01

    Full Text Available In KSTAR device, a 110 GHz ECH system has been a useful heating device for a stable plasma start-up because a pure ohmic discharge scenario with a limited loop voltage of about 4 V was sometimes not successful for burn-through and plasma current ramp-up due to inconsistent wall conditioning and density control. Even though a pure ohmic discharge also was successful, the application of X2-mode ECH could reduce the flux consumption of poloidal field coils, leading to long pulse discharges. The ECH power was injected at the time of the field null formation after the onset of the toroidal electric field in which the electron temperature significantly increased up to 100 eV so that burn-through is overcome. The ECH heating enabled the formation of close flux surfaces earlier, leading to the reliable plasma current ramp-up, but, it caused outward plasma movement and failure of the plasma control, resulting in loss of the discharge. Moreover, impurities from the plasma facing components caused by not fully absorbed ECH power had a detrimental effect on the H-mode transition. In ECH-assisted start-up in the ramp-up phase, ECH power was mainly used for central electron heating, leading to reduction of the flux consumption of the central coils by increasing the electron temperature along with a density increase in the ramp-up phase. When X2-mode ECH power of 350 kW was injected at the mid-plane with a toroidal angle of 10 degree for 1 sec after the onset of the loop voltage, the flux consumption was reduced by about 30% in comparison with the pure ohmic discharges.

  6. An Improved Phase Gradient Autofocus Algorithm Used in Real-time Processing

    Directory of Open Access Journals (Sweden)

    Qing Ji-ming

    2015-10-01

    Full Text Available The Phase Gradient Autofocus (PGA algorithm can remove the high order phase error effectively, which is of great significance to get high resolution images in real-time processing. While PGA usually needs iteration, which necessitates long working hours. In addition, the performances of the algorithm are not stable in different scene applications. This severely constrains the application of PGA in real-time processing. Isolated scatter selection and windowing are two important algorithmic steps of Phase Gradient Autofocus Algorithm. Therefore, this paper presents an isolated scatter selection method based on sample mean and a windowing method based on pulse envelope. These two methods are highly adaptable to data, which would make the algorithm obtain better stability and need less iteration. The adaptability of the improved PGA is demonstrated with the experimental results of real radar data.

  7. Three-Phase Time-Multiplexed Planar Power Transmission to Distributed Implants.

    Science.gov (United States)

    Lee, Byunghun; Ahn, Dukju; Ghovanloo, Maysam

    2016-03-01

    A platform has been presented for wireless powering of receivers (Rx's) that are arbitrarily distributed over a large area. A potential application could be powering of small Rx implants, distributed over large areas of the brain. The transmitter (Tx) consists of three overlapping layers of hexagonal planar spiral coils (hex-PSC) that are horizontally shifted to provide the strongest and most homogeneous electromagnetic flux coverage. The three-layer hex-PSC array is driven by a three-phase time-division-multiplexed power Tx that takes the advantage of the carrier phase shift, coil geometries, and Rx time constant to homogeneously power the arbitrarily distributed Rx's regardless of their misalignments. The functionality of the proposed three-phase power transmission concept has been verified in a detailed scaled-up high-frequency structure simulator Advanced Design System simulation model and measurement setup, and compared with a conventional Tx. The new Tx delivers 5.4 mW to each Rx and achieves, on average, 5.8% power transfer efficiency to the Rx at the worst case 90° angular misalignment, compared with 1.4% by the conventional Tx.

  8. Fully phase-encoded MRI near metallic implants using ultrashort echo times and broadband excitation.

    Science.gov (United States)

    Wiens, Curtis N; Artz, Nathan S; Jang, Hyungseok; McMillan, Alan B; Koch, Kevin M; Reeder, Scott B

    2018-04-01

    To develop a fully phase-encoded MRI method for distortion-free imaging near metallic implants, in clinically feasible acquisition times. An accelerated 3D fully phase-encoded acquisition with broadband excitation and ultrashort echo times is presented, which uses a broadband radiofrequency pulse to excite the entire off-resonance induced by the metallic implant. Furthermore, fully phase-encoded imaging is used to prevent distortions caused by frequency encoding, and to obtain ultrashort echo times for rapidly decaying signal. Phantom and in vivo acquisitions were used to describe the relationship among excitation bandwidth, signal loss near metallic implants, and T 1 weighting. Shorter radiofrequency pulses captured signal closer to the implant by improving spectral coverage and allowing shorter echo times, whereas longer pulses improved T 1 weighting through larger maximum attainable flip angles. Comparisons of fully phase-encoded acquisition with broadband excitation and ultrashort echo times to T 1 -weighted multi-acquisition with variable resonance image combination selective were performed in phantoms and subjects with metallic knee and hip prostheses. These acquisitions had similar contrast and acquisition efficiency. Accelerated fully phase-encoded acquisitions with ultrashort echo times and broadband excitation can generate distortion free images near metallic implants in clinically feasible acquisition times. Magn Reson Med 79:2156-2163, 2018. © 2017 International Society for Magnetic Resonance in Medicine. © 2017 International Society for Magnetic Resonance in Medicine.

  9. Identification of two-phase flow regimes by time-series modeling

    International Nuclear Information System (INIS)

    King, C.H.; Ouyang, M.S.; Pei, B.S.

    1987-01-01

    The identification of two-phase flow patterns in pipes or ducts is important to the design and operation of thermal-hydraulic systems, especially in the nuclear reactor cores of boiling water reactors or in the steam generators of pressurized water reactors. Basically, two-phase flow shows some fluctuating characteristics even at steady-state conditions. These fluctuating characteristics can be analyzed by statistical methods for obtaining flow signatures. There have been a number of experimental studies conducted that are concerned with the statistical properties of void fraction or pressure pulsation in two-phase flow. In this study, the authors propose a new technique of identifying the patterns of air-water two-phase flow in a vertical pipe. This technique is based on analyzing the statistic characteristics of the pressure signals of the test loop by time-series modeling

  10. Healthy Start vitamins—a missed opportunity: findings of a multimethod study

    Science.gov (United States)

    McFadden, Alison; Green, Josephine M; McLeish, Jenny; McCormick, Felicia; Williams, Victoria; Renfrew, Mary J

    2015-01-01

    Objective To evaluate and provide a real-life view of the operation of the Healthy Start vitamins scheme. Setting The study took place in primary care and community settings that served rural, urban and ethnically diverse populations, in two sentinel sites: London, and Yorkshire and the Humber. An online consultation and stakeholder workshops elicited views from across England. Participants 669 health and social care practitioners including health visitors, midwives, public health practitioners, general practitioners, paediatricians and support staff participated in focus group discussions (n=49) and an online consultation (n=620). 56 participants representing health and social care practitioners, policymakers, service commissioners, and voluntary and independent sectors took part in stakeholder workshops. Methods Three-phase multimethod study comprising focus group discussions, an online consultation and stakeholder workshops. Qualitative data were analysed thematically and quantitative data from the online survey were analysed using descriptive statistics. Results Study participants were concerned about the low uptake of Healthy Start vitamin supplements and the consequences of this for health outcomes for women and young children. They experienced Healthy Start vitamin distribution as logistically complex, requiring the time, resources and creative thinking of a range of local and regional practitioners from senior strategists to administrative support workers. In the light of this, many participants argued that moving to universal provision of vitamin supplements would be more cost-effective than the current system. Conclusions There is consistency of views of health practitioners that the current targeted system of providing free vitamin supplements for low-income childbearing women and young children via the Healthy Start programme is not fulfilling its potential to address vitamin deficiencies. There is wide professional and voluntary sector support for

  11. Start up testing for the secure automated fabrication line

    International Nuclear Information System (INIS)

    Gerber, E.W.; Benson, E.M.; Dahl, R.E.

    1986-01-01

    The Secure Automated Fabrication (SAF) Line has been designed and built by Westinghouse Hanford Company for the Department of Energy at the Hanford Site near Richland, Washington. The SAF Line will provide the capability for remote manufacture of fuel for Liquid Metal Reactors, and will supply fuel for the Fast Flux Test Facility (FFTF). The SAF process is highly automated and represents a major advancement in nuclear fuel manufacturing, offering significant improvements in product quality, productivity, safety, and accountability of Special Nuclear Materials. The construction phase of the project is complete, and testing has been initiated to accomplish start up of the plant for manufacture of FFTF fuel. This paper describes the test methodology used for SAF Line start up

  12. A chronotype comparison of South African and Dutch marathon runners: The role of scheduled race start times and effects on performance.

    Science.gov (United States)

    Henst, Rob H P; Jaspers, Richard T; Roden, Laura C; Rae, Dale E

    2015-01-01

    Recently, a high prevalence of morning-types was reported among trained South African endurance athletes. Proposed explanations for this observation were that either the chronotype of these athletes is better suited to coping with the early-morning start times of endurance events in South Africa; or habitual early waking for training or endurance events may have conditioned the athletes to adapt and become morning-types. The South African endurance athletes also had earlier chronotypes compared to a control population of less active individuals, suggesting that individuals who are more physically active may have earlier chronotypes. However, since both the South African athlete and control groups showed an overrepresentation of morning-types compared to European and American populations, the South African climate may in part have explained this bias towards morningness. Given the latitude and climate differences between South Africa and the Netherlands, and that South African marathons typically start at about 06:30 while those in the Netherlands start later (±11:00), comparison of South African and Dutch marathon runners and active controls would allow for simultaneous assessment of the effects of marathon start time, degree of physical activity and climate on chronotype. Therefore, the primary aims of this study were: (i) to assess the effect of marathon start time on chronotype in marathon runners and (ii) to determine the extent to which either degree of physical activity or climate might explain the bias towards morningness observed in South African athletes and controls. A secondary aim was to determine whether any relationships exist between chronotype, PERIOD3 (PER3) variable number tandem repeat (VNTR) polymorphism genotype, habitual training habits and marathon performance. Trained male marathon runners from South Africa (n = 95) and the Netherlands (n = 90), and active but non-competitive male controls from South Africa (n = 97) and the

  13. X-Ray Pulsar Based Navigation and Time Determination, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Microcosm will build on the Phase I X-ray pulsar-based navigation and timing (XNAV) feasibility assessment to develop a detailed XNAV simulation capability to...

  14. A Healthy Start Can Begin Now

    Science.gov (United States)

    A healthy pregnancy begins before you ever become pregnant. Give yourself the best chance for a healthy pregnancy and healthy baby before you start down the road to motherhood. If you smoke, now’s a great time to quit.

  15. Security-enhanced chaos communication with time-delay signature suppression and phase encryption.

    Science.gov (United States)

    Xue, Chenpeng; Jiang, Ning; Lv, Yunxin; Wang, Chao; Li, Guilan; Lin, Shuqing; Qiu, Kun

    2016-08-15

    A security-enhanced chaos communication scheme with time delay signature (TDS) suppression and phase-encrypted feedback light is proposed, in virtue of dual-loop feedback with independent high-speed phase modulation. We numerically investigate the property of TDS suppression in the intensity and phase space and quantitatively discuss security of the proposed system by calculating the bit error rate of eavesdroppers who try to crack the system by directly filtering the detected signal or by using a similar semiconductor laser to synchronize the link signal and extract the data. The results show that TDS embedded in the chaotic carrier can be well suppressed by properly setting the modulation frequency, which can keep the time delay a secret from the eavesdropper. Moreover, because the feedback light is encrypted, without the accurate time delay and key, the eavesdropper cannot reconstruct the symmetric operation conditions and decode the correct data.

  16. Multi-Objective Optimization of Start-up Strategy for Pumped Storage Units

    Directory of Open Access Journals (Sweden)

    Jinjiao Hou

    2018-05-01

    Full Text Available This paper proposes a multi-objective optimization method for the start-up strategy of pumped storage units (PSU for the first time. In the multi-objective optimization method, the speed rise time and the overshoot during the process of the start-up are taken as the objectives. A precise simulation platform is built for simulating the transient process of start-up, and for calculating the objectives based on the process. The Multi-objective Particle Swarm Optimization algorithm (MOPSO is adopted to optimize the widely applied start-up strategies based on one-stage direct guide vane control (DGVC, and two-stage DGVC. Based on the Pareto Front obtained, a multi-objective decision-making method based on the relative objective proximity is used to sort the solutions in the Pareto Front. Start-up strategy optimization for a PSU of a pumped storage power station in Jiangxi Province in China is conducted in experiments. The results show that: (1 compared with the single objective optimization, the proposed multi-objective optimization of start-up strategy not only greatly shortens the speed rise time and the speed overshoot, but also makes the speed curve quickly stabilize; (2 multi-objective optimization of strategy based on two-stage DGVC achieves better solution for a quick and smooth start-up of PSU than that of the strategy based on one-stage DGVC.

  17. A novel approach to delayed-start analyses for demonstrating disease-modifying effects in Alzheimer's disease.

    Directory of Open Access Journals (Sweden)

    Hong Liu-Seifert

    Full Text Available One method for demonstrating disease modification is a delayed-start design, consisting of a placebo-controlled period followed by a delayed-start period wherein all patients receive active treatment. To address methodological issues in previous delayed-start approaches, we propose a new method that is robust across conditions of drug effect, discontinuation rates, and missing data mechanisms. We propose a modeling approach and test procedure to test the hypothesis of noninferiority, comparing the treatment difference at the end of the delayed-start period with that at the end of the placebo-controlled period. We conducted simulations to identify the optimal noninferiority testing procedure to ensure the method was robust across scenarios and assumptions, and to evaluate the appropriate modeling approach for analyzing the delayed-start period. We then applied this methodology to Phase 3 solanezumab clinical trial data for mild Alzheimer's disease patients. Simulation results showed a testing procedure using a proportional noninferiority margin was robust for detecting disease-modifying effects; conditions of high and moderate discontinuations; and with various missing data mechanisms. Using all data from all randomized patients in a single model over both the placebo-controlled and delayed-start study periods demonstrated good statistical performance. In analysis of solanezumab data using this methodology, the noninferiority criterion was met, indicating the treatment difference at the end of the placebo-controlled studies was preserved at the end of the delayed-start period within a pre-defined margin. The proposed noninferiority method for delayed-start analysis controls Type I error rate well and addresses many challenges posed by previous approaches. Delayed-start studies employing the proposed analysis approach could be used to provide evidence of a disease-modifying effect. This method has been communicated with FDA and has been

  18. Time dependent start-up thermal analysis of a Super Fast Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Sutanto,, E-mail: sutanto@fuji.waseda.jp; Oka, Yoshiaki

    2013-10-15

    Highlights: • Time dependent startup thermal analysis of a Super Fast Reactor is performed. • A recirculation system is used for pressurization and for generating supercritical steam. • MCST satisfies the criterion both during subcritical pressure and during power-raising. • MCST is not sensitive to the change of inlet temperature, gap volume and flow rate because of high flow to power ratio. • CHF is not limiting the MCST during subcritical pressure due to large margin of heat flux. -- Abstract: The startup system of a supercritical pressure light water cooled fast reactor (Super FR) is studied by time dependent thermal-hydraulic analysis. The plant analysis code is developed based on an innovative upward flow pattern in all the assemblies of the Super FR. A recirculation system consisting of a steam drum, a circulation pump, and a heat exchanger is used for the startup. Detailed procedures are performed and the maximum cladding surface temperature (MCST) at rated power, 640 °C, is used as the criterion. Firstly a small constant nuclear power is used for rising the core feed water temperature to be 280 °C through the recirculation system. Secondly, pressurization is done in the recirculation system from atmospheric to operating pressure, 25 MPa, by raising the power. Thirdly, line-switching from recirculation mode to once-through direct-cycle is performed while turbines are started by supercritical steam at supercritical pressure. Finally the power is raised to be 100% of power followed by raising the flow rate. During pressurization the heat flux margin is large due to low power used for pressurization and the MCST is much lower than the criterion. The MCST is not sensitive to the inlet temperature, the flow rate, and the gap volume of the core because of high flow to power ratio. Smaller dimension of steam drum can be used for pressurization stably. The MCST satisfies the criterion both during subcritical pressure and during power-raising.

  19. Time dependent start-up thermal analysis of a Super Fast Reactor

    International Nuclear Information System (INIS)

    Sutanto,; Oka, Yoshiaki

    2013-01-01

    Highlights: • Time dependent startup thermal analysis of a Super Fast Reactor is performed. • A recirculation system is used for pressurization and for generating supercritical steam. • MCST satisfies the criterion both during subcritical pressure and during power-raising. • MCST is not sensitive to the change of inlet temperature, gap volume and flow rate because of high flow to power ratio. • CHF is not limiting the MCST during subcritical pressure due to large margin of heat flux. -- Abstract: The startup system of a supercritical pressure light water cooled fast reactor (Super FR) is studied by time dependent thermal-hydraulic analysis. The plant analysis code is developed based on an innovative upward flow pattern in all the assemblies of the Super FR. A recirculation system consisting of a steam drum, a circulation pump, and a heat exchanger is used for the startup. Detailed procedures are performed and the maximum cladding surface temperature (MCST) at rated power, 640 °C, is used as the criterion. Firstly a small constant nuclear power is used for rising the core feed water temperature to be 280 °C through the recirculation system. Secondly, pressurization is done in the recirculation system from atmospheric to operating pressure, 25 MPa, by raising the power. Thirdly, line-switching from recirculation mode to once-through direct-cycle is performed while turbines are started by supercritical steam at supercritical pressure. Finally the power is raised to be 100% of power followed by raising the flow rate. During pressurization the heat flux margin is large due to low power used for pressurization and the MCST is much lower than the criterion. The MCST is not sensitive to the inlet temperature, the flow rate, and the gap volume of the core because of high flow to power ratio. Smaller dimension of steam drum can be used for pressurization stably. The MCST satisfies the criterion both during subcritical pressure and during power-raising

  20. LHC Report: Rocky re-start

    CERN Multimedia

    Barbara Holzer for the LHC Team

    2012-01-01

    A rocky re-start with beam followed a successful machine development period and the first technical stop of 2012. Today, Friday 11 May, the machine began running again with 1380 bunches.   A short, two-day machine development period was successfully completed on 21-22 April. It focused on topics relevant for the 2012 physics beam operation. This was then followed by a five-day technical stop, the first of the year. The technical stop finished on time on Friday 26 April. The re-start with beam was somewhat tortuous and hampered by an unlucky succession of technical faults leading to extended periods of downtime. The planned intensity increase was put on hold for three days with the machine operating with 1092 bunches and a moderate bunch intensity of 1.3x1011 protons. This delivered a reasonable peak luminosity of 3.6x1033 cm-2s-1 to ATLAS and CMS. Higher than usual beam losses were observed in the ramp and squeeze, and time was required to investigate the causes and to implement mitigati...

  1. A Review on Cold Start of Proton Exchange Membrane Fuel Cells

    Directory of Open Access Journals (Sweden)

    Zhongmin Wan

    2014-05-01

    Full Text Available Successful and rapid startup of proton exchange membrane fuel cells (PEMFCs at subfreezing temperatures (also called cold start is of great importance for their commercialization in automotive and portable devices. In order to maintain good proton conductivity, the water content in the membrane must be kept at a certain level to ensure that the membrane remains fully hydrated. However, the water in the pores of the catalyst layer (CL, gas diffusion layer (GDL and the membrane may freeze once the cell temperature decreases below the freezing point (Tf. Thus, methods which could enable the fuel cell startup without or with slight performance degradation at subfreezing temperature need to be studied. This paper presents an extensive review on cold start of PEMFCs, including the state and phase changes of water in PEMFCs, impacts of water freezing on PEMFCs, numerical and experimental studies on PEMFCs, and cold start strategies. The impacts on each component of the fuel cell are discussed in detail. Related numerical and experimental work is also discussed. It should be mentioned that the cold start strategies, especially the enumerated patents, are of great reference value on the practical cold start process.

  2. Effects of partial time delays on phase synchronization in Watts-Strogatz small-world neuronal networks

    Science.gov (United States)

    Sun, Xiaojuan; Perc, Matjaž; Kurths, Jürgen

    2017-05-01

    In this paper, we study effects of partial time delays on phase synchronization in Watts-Strogatz small-world neuronal networks. Our focus is on the impact of two parameters, namely the time delay τ and the probability of partial time delay pdelay, whereby the latter determines the probability with which a connection between two neurons is delayed. Our research reveals that partial time delays significantly affect phase synchronization in this system. In particular, partial time delays can either enhance or decrease phase synchronization and induce synchronization transitions with changes in the mean firing rate of neurons, as well as induce switching between synchronized neurons with period-1 firing to synchronized neurons with period-2 firing. Moreover, in comparison to a neuronal network where all connections are delayed, we show that small partial time delay probabilities have especially different influences on phase synchronization of neuronal networks.

  3. Measurement of time delay for a prospectively gated CT simulator

    Directory of Open Access Journals (Sweden)

    Goharian M

    2010-01-01

    Full Text Available For the management of mobile tumors, respiratory gating is the ideal option, both during imaging and during therapy. The major advantage of respiratory gating during imaging is that it is possible to create a single artifact-free CT data-set during a selected phase of the patient′s breathing cycle. The purpose of the present work is to present a simple technique to measure the time delay during acquisition of a prospectively gated CT. The time delay of a Philips Brilliance BigBore™ (Philips Medical Systems, Madison, WI scanner attached to a Varian Real-Time Position Management™ (RPM system (Varian Medical Systems, Palo Alto, CA was measured. Two methods were used to measure the CT time delay: using a motion phantom and using a recorded data file from the RPM system. In the first technique, a rotating wheel phantom was altered by placing two plastic balls on its axis and rim, respectively. For a desired gate, the relative positions of the balls were measured from the acquired CT data and converted into corresponding phases. Phase difference was calculated between the measured phases and the desired phases. Using period of motion, the phase difference was converted into time delay. The Varian RPM system provides an external breathing signal; it also records transistor-transistor logic (TTL ′X-Ray ON′ status signal from the CT scanner in a text file. The TTL ′X-Ray ON′ indicates the start of CT image acquisition. Thus, knowledge of the start time of CT acquisition, combined with the real-time phase and amplitude data from the external respiratory signal, provides time-stamping of all images in an axial CT scan. The TTL signal with time-stamp was used to calculate when (during the breathing cycle a slice was recorded. Using the two approaches, the time delay between the prospective gating signal and CT simulator has been determined to be 367 ± 40 ms. The delay requires corrections both at image acquisition and while setting gates for

  4. Measurement of time delay for a prospectively gated CT simulator

    International Nuclear Information System (INIS)

    Goharian, M.; Khan, R.F.H.

    2010-01-01

    For the management of mobile tumors, respiratory gating is the ideal option, both during imaging and during therapy. The major advantage of respiratory gating during imaging is that it is possible to create a single artifact-free CT data-set during a selected phase of the patient's breathing cycle. The purpose of the present work is to present a simple technique to measure the time delay during acquisition of a prospectively gated CT. The time delay of a Philips Brilliance BigBore (Philips Medical Systems, Madison, WI) scanner attached to a Varian Real-Time Position Management (RPM) system (Varian Medical Systems, Palo Alto, CA) was measured. Two methods were used to measure the CT time delay: using a motion phantom and using a recorded data file from the RPM system. In the first technique, a rotating wheel phantom was altered by placing two plastic balls on its axis and rim, respectively. For a desired gate, the relative positions of the balls were measured from the acquired CT data and converted into corresponding phases. Phase difference was calculated between the measured phases and the desired phases. Using period of motion, the phase difference was converted into time delay. The Varian RPM system provides an external breathing signal; it also records transistor-transistor logic (TTL) 'X-Ray ON' status signal from the CT scanner in a text file. The TTL 'X-Ray ON' indicates the start of CT image acquisition. Thus, knowledge of the start time of CT acquisition, combined with the real-time phase and amplitude data from the external respiratory signal, provides time-stamping of all images in an axial CT scan. The TTL signal with time-stamp was used to calculate when (during the breathing cycle) a slice was recorded. Using the two approaches, the time delay between the prospective gating signal and CT simulator has been determined to be 367 ± 40 ms. The delay requires corrections both at image acquisition and while setting gates for the treatment delivery

  5. Toward Continuous GPS Carrier-Phase Time Transfer: Eliminating the Time Discontinuity at an Anomaly.

    Science.gov (United States)

    Yao, Jian; Levine, Judah; Weiss, Marc

    2015-01-01

    The wide application of Global Positioning System (GPS) carrier-phase (CP) time transfer is limited by the problem of boundary discontinuity (BD). The discontinuity has two categories. One is "day boundary discontinuity," which has been studied extensively and can be solved by multiple methods [1-8]. The other category of discontinuity, called "anomaly boundary discontinuity (anomaly-BD)," comes from a GPS data anomaly. The anomaly can be a data gap (i.e., missing data), a GPS measurement error (i.e., bad data), or a cycle slip. Initial study of the anomaly-BD shows that we can fix the discontinuity if the anomaly lasts no more than 20 min, using the polynomial curve-fitting strategy to repair the anomaly [9]. However, sometimes, the data anomaly lasts longer than 20 min. Thus, a better curve-fitting strategy is in need. Besides, a cycle slip, as another type of data anomaly, can occur and lead to an anomaly-BD. To solve these problems, this paper proposes a new strategy, i.e., the satellite-clock-aided curve fitting strategy with the function of cycle slip detection. Basically, this new strategy applies the satellite clock correction to the GPS data. After that, we do the polynomial curve fitting for the code and phase data, as before. Our study shows that the phase-data residual is only ~3 mm for all GPS satellites. The new strategy also detects and finds the number of cycle slips by searching the minimum curve-fitting residual. Extensive examples show that this new strategy enables us to repair up to a 40-min GPS data anomaly, regardless of whether the anomaly is due to a data gap, a cycle slip, or a combination of the two. We also find that interference of the GPS signal, known as "jamming", can possibly lead to a time-transfer error, and that this new strategy can compensate for jamming outages. Thus, the new strategy can eliminate the impact of jamming on time transfer. As a whole, we greatly improve the robustness of the GPS CP time transfer.

  6. Getting started with Simulink

    CERN Document Server

    Zamboni, Luca

    2013-01-01

    This practical and easy-to-understand learning tutorial is one big exciting exercise for students and engineers that are always short on their schedules and want to regain some lost time with the help of Simulink.This book is aimed at students and engineers who need a quick start with Simulink. Though it's not required in order to understand how Simulink works, knowledge of physics will help the reader to understand the exercises described.

  7. A novel start algorithm for CNG engines using ion sense technology

    NARCIS (Netherlands)

    Bie, T. de; Ericsson, M.; Rask, P.

    2000-01-01

    This paper presents a start algorithm that is able to control the air/fuel ratio (AFR) during the cranking phase and immediately hereafter, where the ordinary ?-control is not yet enabled. The control is based on the ion sense principle, which means that a current through the spark plug is measured

  8. Dynamics and Control During Start-Up of Energy Integrated Distillation Column

    DEFF Research Database (Denmark)

    of the inherent effects of process integration upon a start-up procedure. In particular the effect of energy recycle upon the possible start-up sequence, and the effect of using an actuator for control purposes, i.e. the heat pump, which in itself requires significant start-up time. The experimental application...

  9. Phase-shifting Real-time Holographic Microscopy applied in micro-structures surface analysis

    International Nuclear Information System (INIS)

    Brito, I V; Gesualdi, M R R; Muramatsu, M; Ricardo, J

    2011-01-01

    The microscopic real-time analysis of micro structured materials is of great importance in various domains of science and technology. For other hand, the holographic interferometry comprises a group of powerful optical methods for non-destructive testing in surface analysis. The holographic microscopy uses the holographic interferometric techniques to obtain quantitative intensity and phase information of the optical waves by microscopic systems. With the development of CCD cameras, computers (hardware and software), and new materials for holographic recording, these techniques can be used to replace the classical form of registration and became promising tools in surface analysis. In this work, we developed a prototype of Photorefractive and Digital Holographic Microscope for real-time analysis of micro-structured systems based on the phase-shifting real-time holographic interferometry techniques. Using this apparatus, we are made analysis of shapes and surfaces to obtain the phase maps and the 3D profiles of some samples.

  10. Comparison of outcomes between emergent-start and planned-start peritoneal dialysis in incident ESRD patients: a prospective observational study.

    Science.gov (United States)

    Li, Wen-Yi; Wang, Yi-Cheng; Hwang, Shang-Jyh; Lin, Shih-Hua; Wu, Kwan-Dun; Chen, Yung-Ming

    2017-12-11

    and cost concerns, such practice of PD initiation would better be replaced with a planned-start mode by employing more effective predialysis therapeutic education and timely catheter placement.

  11. Relationship between push phase and final race time in skeleton performance.

    Science.gov (United States)

    Zanoletti, Costanza; La Torre, Antonio; Merati, Giampiero; Rampinini, Ermanno; Impellizzeri, Franco M

    2006-08-01

    The aim of this study was to examine the relationship between push-time and final race time in skeleton participants during a series of major international competitions to determine the importance of the push phase in skeleton performance. Correlations were computed from the first and second heat split data measured during 24 men and 24 women skeleton competitions. Body mass, height, age, and years of experience of the first 30 men and women athletes of the skeleton, bobsleigh and luge 2003-2004 World Cup ranking were used for the comparison between sliding sports. Moderate but significant correlations (p push-time and final race time in men (r(mean) = 0.48) and women (r(mean) = 0.63). No correlations were found between changes in the individual push-time between the first and second heat with the corresponding changes in final race time. The bobsleigh sliders are heavier than the athletes of the other sliding disciplines. Luge athletes have more experience and are younger than bobsleigh and skeleton sliders. The results of this study suggest that a fast push phase is a prerequisite to success in competition and confirms that the selection of skeleton athletes based on the ability to accelerate to a maximum speed quickly could be valid. However, a good or improved push-time does not ensure a placement in the top finishing positions. On the basis of these results, we suggest that strength and power training is necessary to maintain a short push-time but additional physical training aimed to enhance the push phase might not reflect performance improvements. The recruitment of younger athletes and an increase of youthful competitive activity may be another effective way to reach international competitive results.

  12. Preparation of Al/Fe-Pillared Clays: Effect of the Starting Mineral.

    Science.gov (United States)

    Muñoz, Helir-Joseph; Blanco, Carolina; Gil, Antonio; Vicente, Miguel-Ángel; Galeano, Luis-Alejandro

    2017-11-28

    Four natural clays were modified with mixed polyoxocations of Al/Fe for evaluating the effect of the physicochemical properties of the starting materials (chemical composition, abundance of expandable clay phases, cationic exchange capacity and textural properties) on final physicochemical and catalytic properties of Al/Fe-PILCs. The aluminosilicate denoted C2 exhibited the highest potential as starting material in the preparation of Al/Fe-PILC catalysts, mainly due to its starting cationic exchange capacity (192 meq/100 g) and the dioctahedral nature of the smectite phase. These characteristics favored the intercalation of the mixed (Al 13- x /Fe x ) 7+ Keggin-type polyoxocations, stabilizing a basal spacing of 17.4 Å and high increase of the BET surface (194 m²/g), mainly represented in microporous content. According to H₂-TPR analyses, catalytic performance of the incorporated Fe in the Catalytic Wet Peroxide Oxidation (CWPO) reaction strongly depends on the level of location in mixed Al/Fe pillars. Altogether, such physicochemical characteristics promoted high performance in CWPO catalytic degradation of methyl orange in aqueous medium at very mild reaction temperatures (25.0 ± 1.0 °C) and pressure (76 kPa), achieving TOC removal of 52% and 70% of azo-dye decolourization in only 75 min of reaction under very low concentration of clay catalyst (0.05 g/L).

  13. Dynamics and Control During Start-up of Energy Integrated Distillation Column

    DEFF Research Database (Denmark)

    Eden, Mario Richard; Koggersbøl, Arne; Hallager, L.

    2000-01-01

    of the inherent effects of process integration upon a start-up procedure. In particular the effect of energy recycle upon the possible start-up sequence, and the effect of using an actuator f or control purposes, i.e. the heat pump, which in itself requires significant start-up time. The experimental application...

  14. Lower limb joint kinetics and ankle joint stiffness in the sprint start push-off.

    Science.gov (United States)

    Charalambous, Laura; Irwin, Gareth; Bezodis, Ian N; Kerwin, David

    2012-01-01

    Sprint push-off technique is fundamental to sprint performance and joint stiffness has been identified as a performance-related variable during dynamic movements. However, joint stiffness for the push-off and its relationship with performance (times and velocities) has not been reported. The aim of this study was to quantify and explain lower limb net joint moments and mechanical powers, and ankle stiffness during the first stance phase of the push-off. One elite sprinter performed 10 maximal sprint starts. An automatic motion analysis system (CODA, 200 Hz) with synchronized force plates (Kistler, 1000 Hz) collected kinematic profiles at the hip, knee, and ankle and ground reaction forces, providing input for inverse dynamics analyses. The lower-limb joints predominately extended and revealed a proximal-to-distal sequential pattern of maximal extensor angular velocity and positive power production. Pearson correlations revealed relationships (P push-off in different ways, depending on the phase of stance considered.

  15. Lean start-up

    DEFF Research Database (Denmark)

    Rasmussen, Erik Stavnsager; Tanev, Stoyan

    2016-01-01

    The risk of launching new products and starting new firms is known to be extremely high. The Lean Start-up approach is a way of reducing these risks and enhancing the chances for success by validating the products and services in the market with customers before launching it in full scale. The ma...... and the final business model. In other words: The start-up must first nail the problem together with the customers, then develop the solution and test, and then in the end scale it to a full-grown business model.......The risk of launching new products and starting new firms is known to be extremely high. The Lean Start-up approach is a way of reducing these risks and enhancing the chances for success by validating the products and services in the market with customers before launching it in full scale. The main...

  16. The new JET phased ICRH array: first experiments and modelling

    Energy Technology Data Exchange (ETDEWEB)

    Bures, M; Bhatnagar, V; Brown, T; Fechner, B; Gormezano, C; Kaye, A; Lennholm, M; Righi, E; Rimini, F; Sibley, A; Start, D; Wade, T [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking; Goulding, R [Oak Ridge National Lab., TN (United States); Lamalle, P [Ecole Royale Militaire, Brussels (Belgium). Lab. de Physique des Plasmas; Nguyen, F [CEA Centre d` Etudes de Cadarache, 13 - Saint-Paul-lez-Durance (France)

    1994-07-01

    New ICRH antennas on JET were designed to couple to the new JET divertor plasma configurations and to improve the Fast Wave Current Drive (FWCD) capabilities. The A2 antenna consists of 4 straps whose currents can be phased at arbitrary angles. The real time automatic tuning acts on frequency, line length (line phase shifters) and stub length. Provision is made for the coupling resistance/plasma position feedback to accommodate the fast changes in antenna loading. The first coupling, tuning and heating results are reported in 0{pi}0{pi}, 0000 and 00{pi}{pi} phasing. A new antenna model is described, which was developed to simulate the measured antenna loading in terms of plasma parameters and to provide a starting point for the real time automatic tuning. 5 refs., 4 figs.

  17. Spectral phase encoding of ultra-short optical pulse in time domain for OCDMA application.

    Science.gov (United States)

    Wang, Xu; Wada, Naoya

    2007-06-11

    We propose a novel reconfigurable time domain spectral phase encoding (SPE) scheme for coherent optical code-division-multiple-access application. In the proposed scheme, the ultra-short optical pulse is stretched by dispersive device and the SPE is done in time domain using high speed phase modulator. The time domain SPE scheme is robust to wavelength drift of the light source and is very flexible and compatible with the fiber optical system. Proof-of-principle experiments of encoding with 16-chip, 20 GHz/chip binary-phase-shift-keying codes and 1.25 Gbps data transmission have been successfully demonstrated together with an arrayed-wave-guide decoder.

  18. From START to NEW START. The dilemma and future of nuclear disarmament; Von START zu NEW START. Das Dilemma und die Zukunft der Nuklearen Abruestung

    Energy Technology Data Exchange (ETDEWEB)

    Plettenberg, Lars

    2012-07-01

    The report describes the existing four agreements on nuclear disarmament: START I (1991). START II (1993), SORT (2002) and NEW START (2010). The chapter on the dependence between nuclear disarmament and strategic stability covers the issues mutual assured destruction (MAD), credibility, overkill capacity; the role of nuclear weapons in the national strategies of the USA and NATO, Russia, Great Britain, France, China and the other nuclear states. Ways out of MAD include disarmament, de-alerting and mutual assured protection (MAP).

  19. ECRH-assisted start-up in ITER

    International Nuclear Information System (INIS)

    Lloyd, B.; Carolan, P.G.; Warrick, C.D.

    1996-07-01

    In ITER, the electric field applied for ionisation and to ramp up the plasma current may be limited to ∼ 0.3 V/m. In this case, based on established theories of the avalanche process, it is shown that ohmic breakdown in ITER is only possible over a narrow range of pressure and magnetic error field. Therefore, ECRH may be necessary to provide robust and reliable start-up. ECRH can ensure prompt breakdown over a wide range of prefill pressure and error field and can also give control over the initial time and location of breakdown. For ECRH-assisted start-up in ITER, the power and pulse length requirements are essentially determined by the need to ensure burnthrough, i.e. complete ionisation of hydrogen and the transition to high ionisation states of impurities. A 0-D code (with inclusion of some 1-D effects) has been developed to analyse burnthrough in ITER. The 0-D simulations indicate that control of the deuterium density is the key factor for ensuring successful start-up in ITER, where the effects of neutral screening and dynamic fuelling by the ex-plasma volume are also crucial. It is concluded that without ECRH, successful start-up will only be possible over a very restricted range of parameters but 3MW of absorbed ECRH power will ensure reasonably robust start-up for a broad range of conditions with beryllium impurity. In the case of carbon impurity, even with an absorbed ECRH power of 5MW one may be restricted to low prefill pressure and/or low carbon concentration for successful start-up. (Author)

  20. Treatment strategies for multiple sclerosis: When to start, when to change, when to stop?

    Science.gov (United States)

    Gajofatto, Alberto; Benedetti, Maria Donata

    2015-01-01

    Multiple sclerosis (MS) is a chronic inflammatory condition of the central nervous system determined by a presumed autoimmune process mainly directed against myelin components but also involving axons and neurons. Acute demyelination shows as clinical relapses that may fully or partially resolve, while chronic demyelination and neuroaxonal injury lead to persistent and irreversible neurological symptoms, often progressing over time. Currently approved disease-modifying therapies are immunomodulatory or immunosuppressive drugs that significantly although variably reduce the frequency of attacks of the relapsing forms of the disease. However, they have limited efficacy in preventing the transition to the progressive phase of MS and are of no benefit after it has started. It is therefore likely that the potential advantage of a given treatment is condensed in a relatively limited window of opportunity for each patient, depending on individual characteristics and disease stage, most frequently but not necessarily in the early phase of the disease. In addition, a sizable proportion of patients with MS may have a very mild clinical course not requiring a disease-modifying therapy. Finally, individual response to existing therapies for MS varies significantly across subjects and the risk of serious adverse events remains an issue, particularly for the newest agents. The present review is aimed at critically describing current treatment strategies for MS with a particular focus on the decision of starting, switching and stopping commercially available immunomodulatory and immunosuppressive therapies. PMID:26244148

  1. Participation in testing and start up operations

    International Nuclear Information System (INIS)

    Prasad, Y.S.R.

    1977-01-01

    Testing and start up operations of a nuclear power plant require careful planning. A detailed program of tests and the responsibility of implementing them is discussed. Requirement of documentation covering the tests and operating procedures is explained. The performance of the system during normal and abnomal operating conditions is analysed and required are modifications carried out. Various phases of commissioning and their significance are explained. Preparation of maintenance documentation and training of operating and maintenance staff during this period are discussed. Necessity of close liaison between the regulatory body and the operating organization is explained. (orig.) [de

  2. Temperature-Controlled High-Speed AFM: Real-Time Observation of Ripple Phase Transitions.

    Science.gov (United States)

    Takahashi, Hirohide; Miyagi, Atsushi; Redondo-Morata, Lorena; Scheuring, Simon

    2016-11-01

    With nanometer lateral and Angstrom vertical resolution, atomic force microscopy (AFM) has contributed unique data improving the understanding of lipid bilayers. Lipid bilayers are found in several different temperature-dependent states, termed phases; the main phases are solid and fluid phases. The transition temperature between solid and fluid phases is lipid composition specific. Under certain conditions some lipid bilayers adopt a so-called ripple phase, a structure where solid and fluid phase domains alternate with constant periodicity. Because of its narrow regime of existence and heterogeneity ripple phase and its transition dynamics remain poorly understood. Here, a temperature control device to high-speed atomic force microscopy (HS-AFM) to observe dynamics of phase transition from ripple phase to fluid phase reversibly in real time is developed and integrated. Based on HS-AFM imaging, the phase transition processes from ripple phase to fluid phase and from ripple phase to metastable ripple phase to fluid phase could be reversibly, phenomenologically, and quantitatively studied. The results here show phase transition hysteresis in fast cooling and heating processes, while both melting and condensation occur at 24.15 °C in quasi-steady state situation. A second metastable ripple phase with larger periodicity is formed at the ripple phase to fluid phase transition when the buffer contains Ca 2+ . The presented temperature-controlled HS-AFM is a new unique experimental system to observe dynamics of temperature-sensitive processes at the nanoscopic level. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Extracting surface waves, hum and normal modes: time-scale phase-weighted stack and beyond

    Science.gov (United States)

    Ventosa, Sergi; Schimmel, Martin; Stutzmann, Eleonore

    2017-10-01

    Stacks of ambient noise correlations are routinely used to extract empirical Green's functions (EGFs) between station pairs. The time-frequency phase-weighted stack (tf-PWS) is a physically intuitive nonlinear denoising method that uses the phase coherence to improve EGF convergence when the performance of conventional linear averaging methods is not sufficient. The high computational cost of a continuous approach to the time-frequency transformation is currently a main limitation in ambient noise studies. We introduce the time-scale phase-weighted stack (ts-PWS) as an alternative extension of the phase-weighted stack that uses complex frames of wavelets to build a time-frequency representation that is much more efficient and fast to compute and that preserve the performance and flexibility of the tf-PWS. In addition, we propose two strategies: the unbiased phase coherence and the two-stage ts-PWS methods to further improve noise attenuation, quality of the extracted signals and convergence speed. We demonstrate that these approaches enable to extract minor- and major-arc Rayleigh waves (up to the sixth Rayleigh wave train) from many years of data from the GEOSCOPE global network. Finally we also show that fundamental spheroidal modes can be extracted from these EGF.

  4. Start-up scenario of compact tori based on REB-injection developed in SPAC-group

    International Nuclear Information System (INIS)

    Ikuta, K.

    1981-01-01

    Quasi-static start-up of compact tori without toroidal field coil is reviewed thoroughly in a proposal of the S-1 spheromak. During the formation phase we should note that the rapid heat loss from the plasma will give a bad effect for the generation of the confinement configuration. In the case of fast start-up of the configuration plasma can safely pass over the dangerous state of the instability toward the desirable stable state with a bonus of producing hot plasma. By this reason it is intended to discuss a fast start-up scenario of the compact tori based on REB injection developed in SPAC group

  5. Getting started in ZBrush an introduction to digital sculpting and illustration

    CERN Document Server

    Johnson, Greg

    2014-01-01

    Getting Started in ZBrush is a gentle introduction to ZBrush, today's premier digital sculpting program. Beginning with the fundamentals of digital sculpting as well as a thorough introduction to the user interface, Getting Started in ZBrush will have you creating a variety of professional-level 3D models in no-time. More than just another button-pushing manual, this comprehensive guide is packed with start-to-finish projects that ease you into the workflow of the program, while at the same time providing tips and tricks that will allow you to achieve certain tasks much more quickly. After pro

  6. Financial time series analysis based on effective phase transfer entropy

    Science.gov (United States)

    Yang, Pengbo; Shang, Pengjian; Lin, Aijing

    2017-02-01

    Transfer entropy is a powerful technique which is able to quantify the impact of one dynamic system on another system. In this paper, we propose the effective phase transfer entropy method based on the transfer entropy method. We use simulated data to test the performance of this method, and the experimental results confirm that the proposed approach is capable of detecting the information transfer between the systems. We also explore the relationship between effective phase transfer entropy and some variables, such as data size, coupling strength and noise. The effective phase transfer entropy is positively correlated with the data size and the coupling strength. Even in the presence of a large amount of noise, it can detect the information transfer between systems, and it is very robust to noise. Moreover, this measure is indeed able to accurately estimate the information flow between systems compared with phase transfer entropy. In order to reflect the application of this method in practice, we apply this method to financial time series and gain new insight into the interactions between systems. It is demonstrated that the effective phase transfer entropy can be used to detect some economic fluctuations in the financial market. To summarize, the effective phase transfer entropy method is a very efficient tool to estimate the information flow between systems.

  7. Motor starting a Brayton cycle power conversion system using a static inverter

    Science.gov (United States)

    Curreri, J. S.; Edkin, R. A.; Kruchowy, R.

    1973-01-01

    The power conversion module of a 2- to 15-kWe Brayton engine was motor started using a three-phase, 400-hertz static inverter as the power source. Motor-static tests were conducted for initial gas loop pressures of 10, 14, and 17 N/sq cm (15, 20, and 25 psia) over a range of initial turbine inlet temperatures from 366 to 550 K (200 to 530 F). The data are presented to show the effects of temperature and pressure on the motor-start characteristics of the rotating unit. Electrical characteristics during motoring are also discussed.

  8. Start-up support for New Brunswick Electric's Point Lepreau nuclear steam generators

    International Nuclear Information System (INIS)

    Schneider, W.; Leroux, A.

    1983-05-01

    The start-up of the 600 MW Point Lepreau reactor provided the opportunity for direct involvement in the important low and medium power start-up phase which was of particular interest because this was a first-of-a-kind reactor type incorporating a new steam generator design. Support included test assistance and test results interpretation for the thermal hydraulic performance of the steam generators and in particular, investigation of water level response to operating pressure, power and feed flow. This work resulted in both a greatly improved understanding of transient characteristics and in a number of beneficial refinements in the control methods

  9. Mobile polishing system of feedwater at start-up feedback from the implementation and future prospects

    International Nuclear Information System (INIS)

    Faure, Celine; Eade, Kevin; Fontan, Guillaume

    2012-09-01

    The reduction of the quantity of Steam Generator (SG) metallic oxides deposits, and maintaining a good chemical composition of the secondary side of SG tubes are some of the main objectives being looked at, in order to reduce the risk of SG corrosion, regardless of the alloy used, right from the start-up phase. For all types of outage, obtaining and maintaining sufficient chemical cleanliness at the start-up requires treatment of the water. The treatments are notably: - Water movements using the purge / make-up water method until the chemical criteria have been met. This method can be long and generate large volumes of discharge. - Using suitable resins to remove pollutants from the water. The advantage of this method is that it is selective. - Filtration, allowing for the removal of any insoluble agent. In order to optimise the start-up process, Gravelines and Blayais Nuclear Power Plants (NPPs) put trials in place towards the end of the 1980s. These trials lead to a water supply treatment installation (mobile polishing system- in French Systeme Mobile d'Epuration, SME) being put in place for the start-up phase, made up of an up-stream filter, a mixed-bed resin pollutant trap and a down-stream filter to prevent losing the fines into the feedwater. At the same time, the manifestation of cracking on the secondary side of the steam generator tubes lead EDF to roll out a water treatment for the feedwater dedicated to the start-up. The choice was made not to install a condensate polishing plant, in order to limit notably the pollution risks (resin leaks or waste from the regeneration in the backwater) following difficulties during regeneration. The positive results from the first trials validated for EDF the choice to give priority to the roll-out of the SME to the NPPs judged to be most critical due to the SG material. The SME, installed on a mobile base, can be used on different units at the same station; this reduced the investment and maintenance costs, and

  10. Multiscale Symbolic Phase Transfer Entropy in Financial Time Series Classification

    Science.gov (United States)

    Zhang, Ningning; Lin, Aijing; Shang, Pengjian

    We address the challenge of classifying financial time series via a newly proposed multiscale symbolic phase transfer entropy (MSPTE). Using MSPTE method, we succeed to quantify the strength and direction of information flow between financial systems and classify financial time series, which are the stock indices from Europe, America and China during the period from 2006 to 2016 and the stocks of banking, aviation industry and pharmacy during the period from 2007 to 2016, simultaneously. The MSPTE analysis shows that the value of symbolic phase transfer entropy (SPTE) among stocks decreases with the increasing scale factor. It is demonstrated that MSPTE method can well divide stocks into groups by areas and industries. In addition, it can be concluded that the MSPTE analysis quantify the similarity among the stock markets. The symbolic phase transfer entropy (SPTE) between the two stocks from the same area is far less than the SPTE between stocks from different areas. The results also indicate that four stocks from America and Europe have relatively high degree of similarity and the stocks of banking and pharmaceutical industry have higher similarity for CA. It is worth mentioning that the pharmaceutical industry has weaker particular market mechanism than banking and aviation industry.

  11. CERN openlab enters fifth phase

    CERN Multimedia

    Andrew Purcell

    2015-01-01

    CERN openlab is a unique public-private partnership between CERN and leading ICT companies. At the start of this year, openlab officially entered its fifth phase, which will run until the end of 2017. For the first time in its history, it has extended beyond the CERN community to include other major European and international research laboratories.   Founded in 2001 to develop the innovative ICT systems needed to cope with the unprecedented computing challenges of the LHC, CERN openlab unites science and industry at the cutting edge of research and innovation. In a white paper published last year, CERN openlab set out the main ICT challenges it will tackle during its fifth phase, namely data acquisition, computing platforms, data storage architectures, computer management and provisioning, networks and connectivity, and data analytics. As it enters its fifth phase, CERN openlab is expanding to include other research laboratories. "Today, research centres in other disciplines are also st...

  12. Time-temperature-sensitization and time-temperature-precipitation behavior of alloy 625

    International Nuclear Information System (INIS)

    Koehler, M.; Heubner, U.

    1996-01-01

    Time-Temperature-Sensitization diagrams have been established for a low-carbon version of alloy 625 (UNS N06625). Sensitization in terms of a 50 microm (2 mils) intergranular penetration criterion starts after about 3 h aging time at 750 C (soft annealed condition) or after less than 1 h aging time at 800 C (solution annealed condition) when tested according to ASTM-G 28 method A. Grain boundary precipitation of carbides occurs during aging of both the soft annealed and the solution annealed material, but the soft annealed material exhibits a more pronounced general precipitation of Ni 3 (Nb,Mo) phase giving rise to more distinct loss of ductility. Sensitization of alloy 625 may be retarded by lowering its iron content

  13. Joint kinetic determinants of starting block performance in athletic sprinting.

    Science.gov (United States)

    Brazil, Adam; Exell, Timothy; Wilson, Cassie; Willwacher, Steffen; Bezodis, Ian N; Irwin, Gareth

    2018-07-01

    The aim of this study was to explore the relationships between lower limb joint kinetics, external force production and starting block performance (normalised average horizontal power, NAHP). Seventeen male sprinters (100 m PB, 10.67 ± 0.32 s) performed maximal block starts from instrumented starting blocks (1000 Hz) whilst 3D kinematics (250 Hz) were also recorded during the block phase. Ankle, knee and hip resultant joint moment and power were calculated at the rear and front leg using inverse dynamics. Average horizontal force applied to the front (r = 0.46) and rear (r = 0.44) block explained 86% of the variance in NAHP. At the joint level, many "very likely" to "almost certain" relationships (r = 0.57 to 0.83) were found between joint kinetic data and the magnitude of horizontal force applied to each block although stepwise multiple regression revealed that 55% of the variance in NAHP was accounted for by rear ankle moment, front hip moment and front knee power. The current study provides novel insight into starting block performance and the relationships between lower limb joint kinetic and external kinetic data that can help inform physical and technical training practices for this skill.

  14. Study on scan timing using a test injection method in head CTA

    International Nuclear Information System (INIS)

    Sekito, Yuichi; Sanada, Hidenori

    2005-01-01

    In head computed tomographic angiography (CTA), circulation from arterial phase to venous phase is more rapid than that in other regions. Therefore, it is necessary to determine correct scan timing to obtain ideal CTA images. A test injection method makes it possible to set correct scan timing from the time density curve (TDC) for each subject. The method, however, has a weak point that is a time lag in an arrival time at peak point of contrast medium on TDC between the test injection and the primary examination because of the difference in total volume of contrast medium used. The purpose of this study calculated the delay time on the TDC in both scans. We used the test injection method and the bolus tracking method in the primary examination. The average errors in start time (Δt1) and slope change time (Δt2) of the contrast medium on the TDC between test injection and primary examination were 0.15 sec and 3.05 sec, respectively. The results indicated that it was important to grasp the delay time in start time and peak arrival time of the contrast medium between test injection and primary examination to obtain ideal images in head CTA. (author)

  15. Geometric Phase of the Gyromotion for Charged Particles in a Time-dependent Magnetic Field

    International Nuclear Information System (INIS)

    Liu, Jian; Qin, Hong

    2011-01-01

    We study the dynamics of the gyrophase of a charged particle in a magnetic field which is uniform in space but changes slowly with time. As the magnetic field evolves slowly with time, the changing of the gyrophase is composed of two parts. The rst part is the dynamical phase, which is the time integral of the instantaneous gyrofrequency. The second part, called geometric gyrophase, is more interesting, and it is an example of the geometric phase which has found many important applications in different branches of physics. If the magnetic field returns to the initial value after a loop in the parameter space, then the geometric gyrophase equals the solid angle spanned by the loop in the parameter space. This classical geometric gyrophase is compared with the geometric phase (the Berry phase) of the spin wave function of an electron placed in the same adiabatically changing magnetic field. Even though gyromotion is not the classical counterpart of the quantum spin, the similarities between the geometric phases of the two cases nevertheless reveal the similar geometric nature of the different physics laws governing these two physics phenomena.

  16. From perception to action: phase-locked gamma oscillations correlate with reaction times in a speeded response task

    Directory of Open Access Journals (Sweden)

    Körner Ursula

    2007-04-01

    Full Text Available Abstract Background Phase-locked gamma oscillations have so far mainly been described in relation to perceptual processes such as sensation, attention or memory matching. Due to its very short latency (≈90 ms such oscillations are a plausible candidate for very rapid integration of sensory and motor processes. Results We measured EEG in 13 healthy participants in a speeded reaction task. Participants had to press a button as fast as possible whenever a visual stimulus was presented. The stimulus was always identical and did not have to be discriminated from other possible stimuli. In trials in which the participants showed a fast response, a slow negative potential over central electrodes starting approximately 800 ms before the response and highly phase-locked gamma oscillations over central and posterior electrodes between 90 and 140 ms after the stimulus were observed. In trials in which the participants showed a slow response, no slow negative potential was observed and phase-locked gamma oscillations were significantly reduced. Furthermore, for slow response trials the phase-locked gamma oscillations were significantly delayed with respect to fast response trials. Conclusion These results indicate the relevance of phase-locked gamma oscillations for very fast (not necessarily detailed integration processes.

  17. Time Domain Terahertz Axial Computed Tomography Non Destructive Evaluation, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — In this Phase 2 project, we propose to develop, construct, and deliver to NASA a computed axial tomography time-domain terahertz (CT TD-THz) non destructive...

  18. Real time quantitative phase microscopy based on single-shot transport of intensity equation (ssTIE) method

    Science.gov (United States)

    Yu, Wei; Tian, Xiaolin; He, Xiaoliang; Song, Xiaojun; Xue, Liang; Liu, Cheng; Wang, Shouyu

    2016-08-01

    Microscopy based on transport of intensity equation provides quantitative phase distributions which opens another perspective for cellular observations. However, it requires multi-focal image capturing while mechanical and electrical scanning limits its real time capacity in sample detections. Here, in order to break through this restriction, real time quantitative phase microscopy based on single-shot transport of the intensity equation method is proposed. A programmed phase mask is designed to realize simultaneous multi-focal image recording without any scanning; thus, phase distributions can be quantitatively retrieved in real time. It is believed the proposed method can be potentially applied in various biological and medical applications, especially for live cell imaging.

  19. Serum Albumin as a Prognostic Marker for Serious Non-AIDS Endpoints in the Strategic Timing of Antiretroviral Treatment (START) Study

    DEFF Research Database (Denmark)

    Ronit, Andreas; Sharma, Shweta; Baker, Jason V

    2018-01-01

    of Antiretroviral Treatment (START) study (NCT00867048) with serum albumin as a fixed and time-updated predictor. Models with exclusion of events during initial follow-up years were built to assess the ability of serum albumin to predict beyond shorter periods of time. Secondarily, we considered hospitalizations...... of serious non-AIDS events (hazard ratio, 0.37 [95% confidence interval, .20-.71]; P = .002). Similar results were obtained in a time-updated model, after controlling for interleukin 6, and after excluding initial follow-up years. Serum albumin was independently associated with hospitalization......Background: Serum albumin may be used to stratify human immunodeficiency virus (HIV)-infected persons with high CD4 count according to their risk of serious non-AIDS endpoints. Methods: Cox proportional hazards models were used to analyze the risk of serious non-AIDS events in the Strategic Timing...

  20. Considerations in the rationale, design and methods of the Strategic Timing of AntiRetroviral Treatment (START) study

    DEFF Research Database (Denmark)

    Babiker, Abdel G; Emery, Sean; Fätkenheuer, Gerd

    2013-01-01

    Untreated human immunodeficiency virus (HIV) infection is characterized by progressive depletion of CD4+ T lymphocyte (CD4) count leading to the development of opportunistic diseases (acquired immunodeficiency syndrome (AIDS)), and more recent data suggest that HIV is also associated with an incr...... is not feasible with currently available drugs. The optimal time to start ART for asymptomatic HIV infection is controversial and remains one of the key unanswered questions in the clinical management of HIV-infected individuals.......Untreated human immunodeficiency virus (HIV) infection is characterized by progressive depletion of CD4+ T lymphocyte (CD4) count leading to the development of opportunistic diseases (acquired immunodeficiency syndrome (AIDS)), and more recent data suggest that HIV is also associated...

  1. Single particle nonlocality, geometric phases and time-dependent boundary conditions

    Science.gov (United States)

    Matzkin, A.

    2018-03-01

    We investigate the issue of single particle nonlocality in a quantum system subjected to time-dependent boundary conditions. We discuss earlier claims according to which the quantum state of a particle remaining localized at the center of an infinite well with moving walls would be specifically modified by the change in boundary conditions due to the wall’s motion. We first prove that the evolution of an initially localized Gaussian state is not affected nonlocally by a linearly moving wall: as long as the quantum state has negligible amplitude near the wall, the boundary motion has no effect. This result is further extended to related confined time-dependent oscillators in which the boundary’s motion is known to give rise to geometric phases: for a Gaussian state remaining localized far from the boundaries, the effect of the geometric phases is washed out and the particle dynamics shows no traces of a nonlocal influence that would be induced by the moving boundaries.

  2. Utilizing time-frequency amplitude and phase synchrony measure to assess feedback processing in a gambling task.

    Science.gov (United States)

    Watts, Adreanna T M; Tootell, Anne V; Fix, Spencer T; Aviyente, Selin; Bernat, Edward M

    2018-04-29

    The neurophysiological mechanisms involved in the evaluation of performance feedback have been widely studied in the ERP literature over the past twenty years, but understanding has been limited by the use of traditional time-domain amplitude analytic approaches. Gambling outcome valence has been identified as an important factor modulating event-related potential (ERP) components, most notably the feedback negativity (FN). Recent work employing time-frequency analysis has shown that processes indexed by the FN are confounded in the time-domain and can be better represented as separable feedback-related processes in the theta (3-7 Hz) and delta (0-3 Hz) frequency bands. In addition to time-frequency amplitude analysis, phase synchrony measures have begun to further our understanding of performance evaluation by revealing how feedback information is processed within and between various brain regions. The current study aimed to provide an integrative assessment of time-frequency amplitude, inter-trial phase synchrony, and inter-channel phase synchrony changes following monetary feedback in a gambling task. Results revealed that time-frequency amplitude activity explained separable loss and gain processes confounded in the time-domain. Furthermore, phase synchrony measures explained unique variance above and beyond amplitude measures and demonstrated enhanced functional integration between medial prefrontal and bilateral frontal, motor, and occipital regions for loss relative to gain feedback. These findings demonstrate the utility of assessing time-frequency amplitude, inter-trial phase synchrony, and inter-channel phase synchrony together to better elucidate the neurophysiology of feedback processing. Copyright © 2017. Published by Elsevier B.V.

  3. Real-time tricolor phase measuring profilometry based on CCD sensitivity calibration

    Science.gov (United States)

    Zhu, Lin; Cao, Yiping; He, Dawu; Chen, Cheng

    2017-02-01

    A real-time tricolor phase measuring profilometry (RTPMP) based on charge coupled device (CCD) sensitivity calibration is proposed. Only one colour fringe pattern whose red (R), green (G) and blue (B) components are, respectively, coded as three sinusoidal phase-shifting gratings with an equivalent shifting phase of 2π/3 is needed and sent to an appointed flash memory on a specialized digital light projector (SDLP). A specialized time-division multiplexing timing sequence actively controls the SDLP to project the fringe patterns in R, G and B channels sequentially onto the measured object in one over seventy-two of a second and meanwhile actively controls a high frame rate monochrome CCD camera to capture the corresponding deformed patterns synchronously with the SDLP. So the sufficient information for reconstructing the three-dimensional (3D) shape in one over twenty-four of a second is obtained. Due to the different spectral sensitivity of the CCD camera to RGB lights, the captured deformed patterns from R, G and B channels cannot share the same peak and valley, which will lead to lower accuracy or even failing to reconstruct the 3D shape. So a deformed pattern amending method based on CCD sensitivity calibration is developed to guarantee the accurate 3D reconstruction. The experimental results verify the feasibility of the proposed RTPMP method. The proposed RTPMP method can obtain the 3D shape at over the video frame rate of 24 frames per second, avoid the colour crosstalk completely and be effective for measuring real-time changing object.

  4. Stop and Restart Effects on Modern Vehicle Starting System Components

    Energy Technology Data Exchange (ETDEWEB)

    Windover, Paul R. [Argonne National Lab. (ANL), Argonne, IL (United States); Owens, Russell J. [Argonne National Lab. (ANL), Argonne, IL (United States); Levinson, Terry M. [Argonne National Lab. (ANL), Argonne, IL (United States); Laughlin, Michael [Argonne National Lab. (ANL), Argonne, IL (United States); Gaines, Linda [Argonne National Lab. (ANL), Argonne, IL (United States)

    2015-01-01

    Many drivers of personal and commercial vehicles believe that turning the vehicle off and on frequently instead of idling will cause premature wear of the starter system (starter motor and starter battery). As a result, they are concerned that the replacement cost of the starter motor and/or battery due to increased manual engine cycling would be more than the cumulative cost of the fuel saved by not idling unnecessarily. A number of variables play a role in addressing this complex concern, including the number of starting cycles per day, the time between starting cycles, the intended design life of the starting system, the amount of fuel used to restart an engine, and the cumulative cost of the saved fuel. Qualitative and quantitative information from a variety of sources was used to develop a life-cycle economic model to evaluate the cost and quantify the realistic factors that are related to the permissible frequency of starter motor cycles for the average vehicle to economically minimize engine idle time. Annual cost savings can be calculated depending on shutdown duration and the number of shutdown cycles per day. Analysis shows that cost savings are realized by eliminating idling exceeding one minute by shutting down the engine and restarting it. For a typical motorist, the damage to starting system components resulting from additional daily start cycles will be negligible. Overall, it was found that starter life is mostly dependent on the total number of start cycles, while battery life is more dependent on ensuring a full charge between start events.

  5. Cold starting characteristics analysis of hydraulic free piston engine

    International Nuclear Information System (INIS)

    Zhang, Shuanlu; Zhao, Zhenfeng; Zhao, Changlu; Zhang, Fujun; Wang, Shan

    2017-01-01

    The cold start characteristic of hydraulic free piston diesel engine may affect its stable operation. Therefore the specific cold start characteristics, such as BDC or TDC positions, pressure in-cylinder, heat release rate, should be investigated in detail. These parameters fluctuate in some regularity in the cod start process. With the development of the free piston engine prototype and the establishment of test bench, the results are obtained. For the dynamic results, the fluctuation range of TDC and BDC positions is 8 mm and decreases with time. The thermodynamic results show that the combustion process is not stable and the pressure in-cylinder fluctuates largely in the cold start process. In addition, the combustion is rapid and knock happens inevitably. In order to investigate the reasons, a CFD model is established for temperature analysis in-cylinder and heat transfer conditions. It is found that higher start wall temperature will lead to more uniform temperature distribution. The delay period may decreases and heat release will move forward. This reason is analyzed by thermodynamic derivation based on the first law of thermodynamics. Finally, the improvement suggestions of cold start strategy are proposed. - Highlights: • The cold start behaviors of HFPE are investigated in detail. • CFD method is used for simulating temperature distribution in start process. • Thermodynamic derivation uncovers the compression temperature distribution. • The improvement suggestions of cold start strategy are proposed.

  6. Real-time control of oxic phase using pH (mV)-time profile in swine wastewater treatment

    International Nuclear Information System (INIS)

    Ga, C.H.; Ra, C.S.

    2009-01-01

    The feasibility of real-time control of the oxic phase using the pH (mV)-time profile in a sequencing batch reactor for swine wastewater treatment was evaluated, and the characteristics of the novel real-time control strategies were analyzed in two different concentrated wastewaters. The nitrogen break point (NBP) on the moving slope change (MSC) of the pH (mV) was designated as a real-time control point, and a pilot-scale sequencing batch reactor (18 m 3 ) was designed to fulfill the objectives of the study. Successful real-time control using the developed control strategy was achieved despite the large variations in the influent strength and the loading rate per cycle. Indeed, complete and consistent removal of NH 4 -N (100% removal) was achieved. There was a strong positive correlation (r 2 = 0.9789) between the loading rate and soluble total organic carbon (TOCs) removal, and a loading rate of 100 g/m 3 /cycle was found to be optimum for TOCs removal. Experimental data showed that the real-time control strategy using the MSC of the pH (mV)-time profile could be utilized successfully for the removal of nitrogen from swine wastewater. Furthermore, the pH (mV) was a more reliable real-time control parameter than the oxidation-reduction potential (ORP) for the control of the oxic phase. However, the nitrate knee point (NKP) appeared more consistently upon the completion of denitrification on the ORP-time profile than on the pH (mV)-time profile.

  7. Fast phase stabilization of a low frequency beat note for atom interferometry

    Energy Technology Data Exchange (ETDEWEB)

    Oh, E.; Horne, R. A.; Sackett, C. A., E-mail: sackett@virginia.edu [Department of Physics, University of Virginia, 382 McCormick Road, Charlottesville, Virginia 22904-4714 (United States)

    2016-06-15

    Atom interferometry experiments rely on the ability to obtain a stable signal that corresponds to an atomic phase. For interferometers that use laser beams to manipulate the atoms, noise in the lasers can lead to errors in the atomic measurement. In particular, it is often necessary to actively stabilize the optical phase between two frequency components of the beams. Typically this is achieved using a time-domain measurement of a beat note between the two frequencies. This becomes challenging when the frequency difference is small and the phase measurement must be made quickly. The method presented here instead uses a spatial interference detection to rapidly measure the optical phase for arbitrary frequency differences. A feedback system operating at a bandwidth of about 10 MHz could then correct the phase in about 3 μs. This time is short enough that the phase correction could be applied at the start of a laser pulse without appreciably degrading the fidelity of the atom interferometer operation. The phase stabilization system was demonstrated in a simple atom interferometer measurement of the {sup 87}Rb recoil frequency.

  8. Critical Incidents Typically Emerging during the Post-Formation Phase of a New Venture: Perspectives for Entrepreneurship Education and Start-up Counselling

    Science.gov (United States)

    Heinrichs, Karin; Jäcklin, Benjamin

    2017-01-01

    During the post-formation phase, young ventures are often in danger of sliding into bankruptcy. The entrepreneur has to deal with a multitude of complex problems, decisions have to be made under time pressure or uncertainty, and upcoming crises have to be perceived in time. This paper presents seven critical incidents that are (1) realistic,…

  9. Relationship between geomagnetic classes’ activity phases and their occurrence during the sunspot cycle

    Directory of Open Access Journals (Sweden)

    Frédéric Ouattara

    2009-06-01

    Full Text Available Four well known geomagnetic classes of activity such as quiet days activity, fluctuating activity, recurrent activity
    and shock activity time occurrences have been determined not only by using time profile of sunspot number
    Rz but also by using aa index values.
    We show that recurrent wind stream activity and fluctuating activity occur in opposite phase and slow solar wind
    activity during minimum phase and shock activity at the maximum phase.
    It emerges from this study that fluctuating activity precedes the sunspot cycle by π/2 and the latter also precedes
    recurrent activity by π/2. Thus in the majority the activities do not happen at random; the sunspot cycle starts
    with quiet days activity, continues with fluctuating activity and during its maximum phase arrives shock activity.
    The descending phase is characterized by the manifestation of recurrent wind stream activity.

  10. Measurement by phase severance

    International Nuclear Information System (INIS)

    Noyes, H.P.

    1987-03-01

    It is claimed that the measurement process is more accurately described by ''quasi-local phase severance'' than by ''wave function collapse''. The approach starts from the observation that the usual route to quantum mechanics starting from the Hamilton-Jacobi equations throws away half the degrees of freedom, namely, the classical initial state parameters. To overcome this difficulty, the full set of Hamilton-Jacobi equations is interpreted as operator equations acting on a state vector. The measurement theory presented is based on the conventional S-matrix boundary condition of N/sub A/ free particles in the distant past and N/sub B/ free particles in the distant future and taking the usual free particle wave functions, multiplied by phase factors

  11. Engine-start Control Strategy of P2 Parallel Hybrid Electric Vehicle

    Science.gov (United States)

    Xiangyang, Xu; Siqi, Zhao; Peng, Dong

    2017-12-01

    A smooth and fast engine-start process is important to parallel hybrid electric vehicles with an electric motor mounted in front of the transmission. However, there are some challenges during the engine-start control. Firstly, the electric motor must simultaneously provide a stable driving torque to ensure the drivability and a compensative torque to drag the engine before ignition. Secondly, engine-start time is a trade-off control objective because both fast start and smooth start have to be considered. To solve these problems, this paper first analyzed the resistance of the engine start process, and established a physic model in MATLAB/Simulink. Then a model-based coordinated control strategy among engine, motor and clutch was developed. Two basic control strategy during fast start and smooth start process were studied. Simulation results showed that the control objectives were realized by applying given control strategies, which can meet different requirement from the driver.

  12. Unsteady numerical simulation for gas–liquid two-phase flow in self-priming process of centrifugal pump

    International Nuclear Information System (INIS)

    Huang, Si; Su, Xianghui; Guo, Jing; Yue, Le

    2014-01-01

    Highlights: • The transient gas–liquid two-phase flow fields in the self-priming centrifugal pump are simulated. • The self-priming time and performance are estimated. • The air void fraction and two phase distribution are obtained.· The hole on the volute plays a significant role for gas exhausting. • The frequency of the impulsive pressure basically conforms to that of the air exhausted out of the pump. - Abstract: Self-priming pumps start up without pre-irrigation, and then work as common pumps when air in the pump is exhausted. The transient gas–liquid flow at the start-up stage inside a self-priming pump is an interesting process which greatly influences performance of the pump. In this paper, a conventional vertical self-priming centrifugal pump was selected as the object. Using unsteady numerical simulation, the authors investigated the transient gas–liquid two-phase flow in the self-priming centrifugal pump during the self-priming process. The main innovation in the simulation was that a section of the suction pipe filled with air was set as the initial condition, which conformed to the actual self-priming conditions. The gas–liquid two-phase distribution, the pressure and velocity in relation to time were computed and analyzed. Flow rates of both phases with time at the pump inlet and outlet were obtained based on the simulation, which could be used to estimate the self-priming time and other performance parameters. Finally, the numerical method and results for gas–liquid two-phase flow in the self-priming pump was partly validated by the pump performance test

  13. 76 FR 37174 - Capital Investment Program-New Starts and Small Starts Program Funds

    Science.gov (United States)

    2011-06-24

    ... DEPARTMENT OF TRANSPORTATION Federal Transit Administration Capital Investment Program--New Starts... apportionment of the FY 2011 Capital Investment (New Starts and Small Starts) program funds. The funds will be... FY 2011, $1,596,800,000 was appropriated for the Capital Investments Grant Account, which includes...

  14. Internal combustion engine cold-start efficiency: A review of the problem, causes and potential solutions

    International Nuclear Information System (INIS)

    Roberts, Andrew; Brooks, Richard; Shipway, Philip

    2014-01-01

    Highlights: • The sources of I.C. engine cold start efficiency are reviewed and quantified. • Potential solutions are reviewed and the benefit quantified together. • Potential conflicts between different engine sub-systems are discussed. • Fuel consumption benefits of up to 7% are observed during cold start. • Emission reductions of up to 40% during cold start are observed. - Abstract: Legislation on vehicle emissions continues to become more stringent in an effort to minimise the impact of internal combustion engines on the environment. One area of significant concern in this respect is that of the cold-start; the thermal efficiency of the internal combustion engine is significantly lower at cold-start than when the vehicle reaches steady state temperatures owing to sub-optimal lubricant and component temperatures. The drive for thermal efficiency (of both the internal combustion engine and of the vehicle as a whole) has led to a variety of solutions being trialled to assess their merits and effects on other vehicle systems during this warm-up phase (and implemented where appropriate). The approaches have a common theme of attempting to reduce energy losses so that systems and components reach their intended operating temperature range as soon as possible after engine start. In the case of the engine, this is primarily focused on the lubricant system. Lubricant viscosity is highly sensitive to temperature and the increased viscosity at low temperatures results in higher frictional and pumping losses than would be observed at the target operating temperature. The approaches used to tackle the problem include the use of phase change materials (to reduce the cool-down rate during a period following engine running) [1,2] and the use of thermal barrier coatings in an attempt to insulate the cylinder bore and prevent heat loss (thus increasing the amount of energy utilised as brake work [3]). A range of system alterations have also been trialled including

  15. Yield of reversible colloidal gels during flow start-up: release from kinetic arrest.

    Science.gov (United States)

    Johnson, Lilian C; Landrum, Benjamin J; Zia, Roseanna N

    2018-06-05

    Yield of colloidal gels during start-up of shear flow is characterized by an overshoot in shear stress that accompanies changes in network structure. Prior studies of yield of reversible colloidal gels undergoing strong flow model the overshoot as the point at which network rupture permits fluidization. However, yield under weak flow, which is of interest in many biological and industrial fluids shows no such disintegration. The mechanics of reversible gels are influenced by bond strength and durability, where ongoing rupture and re-formation impart aging that deepens kinetic arrest [Zia et al., J. Rheol., 2014, 58, 1121], suggesting that yield be viewed as release from kinetic arrest. To explore this idea, we study reversible colloidal gels during start-up of shear flow via dynamic simulation, connecting rheological yield to detailed measurements of structure, bond dynamics, and potential energy. We find that pre-yield stress grows temporally with the changing roles of microscopic transport processes: early time behavior is set by Brownian diffusion; later, advective displacements permit relative particle motion that stretches bonds and stores energy. Stress accumulates in stretched, oriented bonds until yield, which is a tipping point to energy release, and is passed with a fully intact network, where the loss of very few bonds enables relaxation of many, easing glassy arrest. This is immediately followed by a reversal to growth in potential energy during bulk plastic deformation and condensation into larger particle domains, supporting the view that yield is an activated release from kinetic arrest. The continued condensation of dense domains and shrinkage of network surfaces, along with a decrease in the potential energy, permit the gel to evolve toward more complete phase separation, supporting our view that yield of weakly sheared gels is a 'non-equilibrium phase transition'. Our findings may be particularly useful for industrial or other coatings, where weak

  16. Epigenetic mismatches with mutated transcribing genes at leukemogenic S-phase binding/start sites--potential targets for therapy with enzyme inhibitors.

    Science.gov (United States)

    Prindull, Gregor

    2012-11-01

    This review focuses on gene transcription patterns of leukemogenic S-phases in mitotic cell cycles for identification of enzymatic reactions as potential targets for epigenetics-based drug therapy. Transcription of leukemic genes is triggered by reprogrammed transcription factors (TFs) mediated by chromatin histones. Reprogrammed TFs originate from transcriptional alterations of CpG methylation patterns of mutated epigenetic genes. They preserve memory information of earlier leukemogenic exposures, even transgenerationally via the zygote, through small (e.g. pi)RNA transmitted between cells by exosomes. Normally, reprogrammed TFs are enzymatically silenced and stored as markers in heterochromatic domains. Failure of intra S-phase surveillance (IS) permits the formation and continual operation of DNA replication forks in spite of persisting genotoxic stress. Silenced TFs are re-activated by euchromatin, most likely through leakages of insulator barriers of cis-regulating chromatin modulators (CRM) that normally separate hetero- from euchromatin domains. During transport by sliding nucleosomes, reprogrammed leukemogenic TFs are misplaced at transcription factor binding-/starting-sites (TFBS /TSS) allowing them to interact with and trigger replication of mutated leukemic genes. Interactions of enzymatically reprogrammed TFs, transcribed from mutated epigenetic genes, with replicating leukemic genes at TFBS/TSSs are key driving forces in leukemogenesis. Probably, epigenetic genes, although mutated, still retain their control of replication of leukemic genes. Epigenetics-based enzyme inhibitors must target reprogrammed TFs. Prudently, therapeutic corrections should be introduced within the frame of conventional, cytoreductive treatment protocols. Alternatively, reprogrammed TFs could be replaced by cell populations with regular TF production. Clinically, classification of leukemias should be based on their epigenetic presentation.

  17. Enhanced Performance by Time-Frequency-Phase Feature for EEG-Based BCI Systems

    Directory of Open Access Journals (Sweden)

    Baolei Xu

    2014-01-01

    Full Text Available We introduce a new motor parameter imagery paradigm using clench speed and clench force motor imagery. The time-frequency-phase features are extracted from mu rhythm and beta rhythms, and the features are optimized using three process methods: no-scaled feature using “MIFS” feature selection criterion, scaled feature using “MIFS” feature selection criterion, and scaled feature using “mRMR” feature selection criterion. Support vector machines (SVMs and extreme learning machines (ELMs are compared for classification between clench speed and clench force motor imagery using the optimized feature. Our results show that no significant difference in the classification rate between SVMs and ELMs is found. The scaled feature combinations can get higher classification accuracy than the no-scaled feature combinations at significant level of 0.01, and the “mRMR” feature selection criterion can get higher classification rate than the “MIFS” feature selection criterion at significant level of 0.01. The time-frequency-phase feature can improve the classification rate by about 20% more than the time-frequency feature, and the best classification rate between clench speed motor imagery and clench force motor imagery is 92%. In conclusion, the motor parameter imagery paradigm has the potential to increase the direct control commands for BCI control and the time-frequency-phase feature has the ability to improve BCI classification accuracy.

  18. Time-dependent Hartree-Fock dynamics and phase transition in Lipkin-Meshkov-Glick model

    International Nuclear Information System (INIS)

    Kan, K.; Lichtner, P.C.; Dworzecka, M.; Griffin, J.J.

    1980-01-01

    The time-dependent Hartree-Fock solutions of the two-level Lipkin-Meshkov-Glick model are studied by transforming the time-dependent Hartree-Fock equations into Hamilton's canonical form and analyzing the qualitative structure of the Hartree-Fock energy surface in the phase space. It is shown that as the interaction strength increases these time-dependent Hartree-Fock solutions undergo a qualitative change associated with the ground state phase transition previously studied in terms of coherent states. For two-body interactions stronger than the critical value, two types of time-dependent Hartree-Fock solutions (the ''librations'' and ''rotations'' in Hamilton's mechanics) exist simultaneously, while for weaker interactions only the rotations persist. It is also shown that the coherent states with the maximum total pseudospin value are determinants, so that time-dependent Hartree-Fock analysis is equivalent to the coherent state method

  19. Phase synchronization based minimum spanning trees for analysis of financial time series with nonlinear correlations

    Science.gov (United States)

    Radhakrishnan, Srinivasan; Duvvuru, Arjun; Sultornsanee, Sivarit; Kamarthi, Sagar

    2016-02-01

    The cross correlation coefficient has been widely applied in financial time series analysis, in specific, for understanding chaotic behaviour in terms of stock price and index movements during crisis periods. To better understand time series correlation dynamics, the cross correlation matrices are represented as networks, in which a node stands for an individual time series and a link indicates cross correlation between a pair of nodes. These networks are converted into simpler trees using different schemes. In this context, Minimum Spanning Trees (MST) are the most favoured tree structures because of their ability to preserve all the nodes and thereby retain essential information imbued in the network. Although cross correlations underlying MSTs capture essential information, they do not faithfully capture dynamic behaviour embedded in the time series data of financial systems because cross correlation is a reliable measure only if the relationship between the time series is linear. To address the issue, this work investigates a new measure called phase synchronization (PS) for establishing correlations among different time series which relate to one another, linearly or nonlinearly. In this approach the strength of a link between a pair of time series (nodes) is determined by the level of phase synchronization between them. We compare the performance of phase synchronization based MST with cross correlation based MST along selected network measures across temporal frame that includes economically good and crisis periods. We observe agreement in the directionality of the results across these two methods. They show similar trends, upward or downward, when comparing selected network measures. Though both the methods give similar trends, the phase synchronization based MST is a more reliable representation of the dynamic behaviour of financial systems than the cross correlation based MST because of the former's ability to quantify nonlinear relationships among time

  20. Integrated Time and Phase Synchronization Strategy for a Multichannel Spaceborne-Stationary Bistatic SAR System

    Directory of Open Access Journals (Sweden)

    Feng Hong

    2016-07-01

    Full Text Available The spatial separation of the transmitter and receiver in Bistatic Synthetic Aperture Radar (BiSAR makes it a promising and useful supplement to a classical Monostatic SAR system (MonoSAR. This paper proposes a novel integrated time and phase synchronization strategy for a multichannel spaceborne-stationary BiSAR system. Firstly, the time synchronization strategy is proposed, which includes Pulse Repetition Frequency (PRF generation under noisy conditions, multichannel calibration and the alignment of the recorded data with the orbital data. Furthermore, the phase synchronization strategy, which fully considers the deteriorative factors in the BiSAR configuration, is well studied. The contribution of the phase synchronization strategy includes two aspects: it not only compensates the phase error, but also improves the Signal to Noise Ratio (SNR of the obtained signals. Specifically, all direct signals on different PRF time can be reconstructed with the shift and phase compensation operation using a reference signal. Besides, since the parameters of the reference signal can be estimated only once using the selected practical direct signal and a priori information, the processing complexity is well reduced. Final imaging results with and without compensation for real data are presented to validate the proposed synchronization strategy.

  1. Preliminary considerations on the startup phase for the ASTRID core

    International Nuclear Information System (INIS)

    Mignot, G.

    2015-01-01

    This paper presents preliminary considerations on the startup phase for the ASTRID core, as well as an overview of the different steps before reaching the optimised equilibrium core. The start-up phase is assumed to cover the period between loading the dummy core into the reactor (for commissioning tests) and achieving the optimised equilibrium core. Four main stages are considered: a first stage of start-up tests before fuel core loading, a second stage related to zero power and power ramp-up tests, a third stage corresponding to the transition from the first core to the equilibrium contractual core, and the last stage to reach the optimised performance for the equilibrium core. In the two last stages, a sub-assembly surveillance plan based on post-irradiation examinations is taken into account. As this work is in its preliminary stages, the first scenarios shown for the start-up phase must not be considered as the ASTRID reference scenarios. The scenarios strongly depend on the assumptions considered in the analysis, whereas those discussed in this paper aim at outlining the content and the duration of the starting phases for the ASTRID core, which will be useful in subsequently assessing the core sub-assembly fabrication needs. Assumptions for the start-up phase will be updated in accordance with progress on the ASTRID core design development and core qualification programme. (author)

  2. Development of portable phased array UT system for real-time flaw imaging

    International Nuclear Information System (INIS)

    Goto, M.

    1995-01-01

    Many functions and features of phased array UT technology must be useful for NDE in the industrial field. Some phased array UT systems have been developed for the inspection of nuclear pressure vessel and turbine components. However, phased array UT is still a special NDE technique and it has not been used widely in the past. The reasons of that are system size, cost, operator performance, equipment design and others. TOSHIBA has newly developed PC controlled portable phased array system to solve those problems. The portable phased array UT system is very compact and light but it is able to drive up to 32-channel linear array probe, to display real-time linear/sector B-scan, to display accumulated B-scan with an encoder and to display profile overlaid B-scan. The first applications were turbine component inspections for precise flaw investigation and flaw image data recording

  3. Exhaust Emission Characteristics of Heavy Duty Diesel Engine During Cold and Warm Start

    Directory of Open Access Journals (Sweden)

    YANG Rong

    2014-07-01

    Full Text Available Through experiment conducted on a six cylinder direct injection diesel engine with SCR catalyst, effects of coolant temperature on rail pressure, injection quantity, excess air coefficient and emissions characteristics during cold and warm start were investigated. The results showed that, the maximum injection quantity during a starting event was several times higher than idling operation mode, so was the maximal opacity in the cold and warm starting process. When coolant temperature rose up to above 20℃, NOX emissions in the starting process exhibited peculiar rise which was times higher than idling mode. Compared with engine warm start, rail pressure, cycle fuel quantity, opacity, CO and HC emissions during engine cold start were higher in the course from their transient maximal values towards stabilized idling status. NOX in the same transient course, however, were lower in cold start. As coolant temperature rose, the maximal and the idling value of rail pressure and cycle fuel injection quantity during diesel engine starting process decreased gradually, the excess air coefficient increased to a certain degree, and the maximal and idling values of NOX increased gradually.

  4. Improvement in motor performance during high pressure pump starting at NDDP, Kalpakkam

    International Nuclear Information System (INIS)

    Nagaraj, R.; Murugan, V.; Thalor, K.L.; Saxena, A.K.; Dangore, A.Y.; Prabhakar, S.; Tiwari, P.K.

    2007-01-01

    The major energy requirement required for a Sea Water Reverse Osmosis is in the form of Electrical Energy. The primary energy requirement in the process is the electrical energy fed to High Pressure Pumps to pressurize the feed sea water to membranes. This High pressure pump being a high inertia load requires very high torque at the time of starting. This high starting torque requirement results in increased acceleration time of the motor which subsequently increases the strain on the upstream electrical system from motor feeder to transformer. Such starting characteristic necessitates provision of special starting scheme for the high pressure pump motors. Sea water reverse osmosis (SWRO) plant of Nuclear Desalination Demonstration Project (NDDP) was commissioned in October 2002 at Kalpakkam, India. This paper presents the experiences of problems faced due to the typical starting characteristics of High Pressure pumps and provision of series reactor type motor starter for the same. (author)

  5. Invariance of the Berry phase under unitary transformations: application to the time-dependent generalized harmonic oscillator

    International Nuclear Information System (INIS)

    Kobe, D.H.

    1989-01-01

    The Berry phase is derived in a manifestly gauge-invariant way, without adiabatic or cyclic requirements. It is invariant under unitary transformations, contrary to recent assertions. A time-dependent generalized harmonic oscillator is taken as an example. The energy of the system is not in general the Hamiltonian. An energy, the time derivative of which is the power, is obtained from the equation of motion. When the system is quantized, the Berry phase is zero, and is invariant under unitary transformations. If the energy is chosen incorrectly to be the Hamiltonian, a nonzero Berry phase is obtained. In this case the total phase, the sun of the dynamical and Berry phases, is equal to the correct total phase through first order in perturbation theory. (author)

  6. Real-time phase correlation based integrated system for seizure detection

    Science.gov (United States)

    Romaine, James B.; Delgado-Restituto, Manuel; Leñero-Bardallo, Juan A.; Rodríguez-Vázquez, Ángel

    2017-05-01

    This paper reports a low area, low power, integer-based digital processor for the calculation of phase synchronization between two neural signals. The processor calculates the phase-frequency content of a signal by identifying the specific time periods associated with two consecutive minima. The simplicity of this phase-frequency content identifier allows for the digital processor to utilize only basic digital blocks, such as registers, counters, adders and subtractors, without incorporating any complex multiplication and or division algorithms. In fact, the processor, fabricated in a 0.18μm CMOS process, only occupies an area of 0.0625μm2 and consumes 12.5nW from a 1.2V supply voltage when operated at 128kHz. These low-area, low-power features make the proposed processor a valuable computing element in closed loop neural prosthesis for the treatment of neural diseases, such as epilepsy, or for extracting functional connectivity maps between different recording sites in the brain.

  7. Getting started with ownCloud

    CERN Document Server

    Patawari, Aditya

    2013-01-01

    This is a standard, precise, and short tutorial for setting up ownCloud and includes advanced topics like encryption, user management, and server security. This ownCloud book would be an ideal starting point for anyone who wants to store their data and also share it.This book is for first time users as well as administrators who are interested or responsible for managing an ownCloud instance. You do not need any prior experience with any of the technology, including Linux/Windows, Apache/IIS, SQLite/MySQL, or even PHP. It is a beginner-friendly book, written with a first time user in mind.

  8. Liquid-solid phase transition of Ge-Sb-Te alloy observed by in-situ transmission electron microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Berlin, Katja, E-mail: katja.berlin@pdi-berlin.de; Trampert, Achim

    2017-07-15

    Melting and crystallization dynamics of the multi-component Ge-Sb-Te alloy have been investigated by in-situ transmission electron microscopy (TEM). Starting point of the phase transition study is an ordered hexagonal Ge{sub 1}Sb{sub 2}Te{sub 4} thin film on Si(111) where the crystal structure and the chemical composition are verified by scanning TEM and electron energy-loss spectroscopy, respectively. The in-situ observation of the liquid phase at 600°C including the liquid-solid and liquid-vacuum interfaces and their movements was made possible due to an encapsulation of the TEM sample. The solid-liquid interface during melting displays a broad and diffuse transition zone characterized by a vacancy induced disordered state. Although the velocities of interface movements are measured to be in the nanometer per second scale, both, for crystallization and solidification, the underlying dynamic processes are considerably different. Melting reveals linear dependence on time, whereas crystallization exhibits a non-linear time-dependency featuring a superimposed start-stop motion. Our results may provide valuable insight into the atomic mechanisms at interfaces during the liquid-solid phase transition of Ge-Sb-Te alloys. - Highlights: • In-situ TEM observation of liquid Ge-Sb-Te phase transition due to encapsulation. • During melting: Observation of non-ordered interface transition due to premelting. • During solidification: Observation of non-linear time-dependent crystallization.

  9. Liquid-solid phase transition of Ge-Sb-Te alloy observed by in-situ transmission electron microscopy

    International Nuclear Information System (INIS)

    Berlin, Katja; Trampert, Achim

    2017-01-01

    Melting and crystallization dynamics of the multi-component Ge-Sb-Te alloy have been investigated by in-situ transmission electron microscopy (TEM). Starting point of the phase transition study is an ordered hexagonal Ge 1 Sb 2 Te 4 thin film on Si(111) where the crystal structure and the chemical composition are verified by scanning TEM and electron energy-loss spectroscopy, respectively. The in-situ observation of the liquid phase at 600°C including the liquid-solid and liquid-vacuum interfaces and their movements was made possible due to an encapsulation of the TEM sample. The solid-liquid interface during melting displays a broad and diffuse transition zone characterized by a vacancy induced disordered state. Although the velocities of interface movements are measured to be in the nanometer per second scale, both, for crystallization and solidification, the underlying dynamic processes are considerably different. Melting reveals linear dependence on time, whereas crystallization exhibits a non-linear time-dependency featuring a superimposed start-stop motion. Our results may provide valuable insight into the atomic mechanisms at interfaces during the liquid-solid phase transition of Ge-Sb-Te alloys. - Highlights: • In-situ TEM observation of liquid Ge-Sb-Te phase transition due to encapsulation. • During melting: Observation of non-ordered interface transition due to premelting. • During solidification: Observation of non-linear time-dependent crystallization.

  10. EEG phase reset due to auditory attention: an inverse time-scale approach

    International Nuclear Information System (INIS)

    Low, Yin Fen; Strauss, Daniel J

    2009-01-01

    We propose a novel tool to evaluate the electroencephalograph (EEG) phase reset due to auditory attention by utilizing an inverse analysis of the instantaneous phase for the first time. EEGs were acquired through auditory attention experiments with a maximum entropy stimulation paradigm. We examined single sweeps of auditory late response (ALR) with the complex continuous wavelet transform. The phase in the frequency band that is associated with auditory attention (6–10 Hz, termed as theta–alpha border) was reset to the mean phase of the averaged EEGs. The inverse transform was applied to reconstruct the phase-modified signal. We found significant enhancement of the N100 wave in the reconstructed signal. Analysis of the phase noise shows the effects of phase jittering on the generation of the N100 wave implying that a preferred phase is necessary to generate the event-related potential (ERP). Power spectrum analysis shows a remarkable increase of evoked power but little change of total power after stabilizing the phase of EEGs. Furthermore, by resetting the phase only at the theta border of no attention data to the mean phase of attention data yields a result that resembles attention data. These results show strong connections between EEGs and ERP, in particular, we suggest that the presentation of an auditory stimulus triggers the phase reset process at the theta–alpha border which leads to the emergence of the N100 wave. It is concluded that our study reinforces other studies on the importance of the EEG in ERP genesis

  11. EEG phase reset due to auditory attention: an inverse time-scale approach.

    Science.gov (United States)

    Low, Yin Fen; Strauss, Daniel J

    2009-08-01

    We propose a novel tool to evaluate the electroencephalograph (EEG) phase reset due to auditory attention by utilizing an inverse analysis of the instantaneous phase for the first time. EEGs were acquired through auditory attention experiments with a maximum entropy stimulation paradigm. We examined single sweeps of auditory late response (ALR) with the complex continuous wavelet transform. The phase in the frequency band that is associated with auditory attention (6-10 Hz, termed as theta-alpha border) was reset to the mean phase of the averaged EEGs. The inverse transform was applied to reconstruct the phase-modified signal. We found significant enhancement of the N100 wave in the reconstructed signal. Analysis of the phase noise shows the effects of phase jittering on the generation of the N100 wave implying that a preferred phase is necessary to generate the event-related potential (ERP). Power spectrum analysis shows a remarkable increase of evoked power but little change of total power after stabilizing the phase of EEGs. Furthermore, by resetting the phase only at the theta border of no attention data to the mean phase of attention data yields a result that resembles attention data. These results show strong connections between EEGs and ERP, in particular, we suggest that the presentation of an auditory stimulus triggers the phase reset process at the theta-alpha border which leads to the emergence of the N100 wave. It is concluded that our study reinforces other studies on the importance of the EEG in ERP genesis.

  12. Development of a phase counter with real-time fringe jump corrector for heterodyne interferometer on LHD

    International Nuclear Information System (INIS)

    Ito, Y.; Tanaka, K.; Tokuzawa, T.; Akiyama, T.; Okajima, S.; Kawahata, K.

    2005-01-01

    Phase counters, which are used with heterodyne interferometers for plasma density measurements, frequently suffer from phase jumping and cause difficulties for data interpretation. An automatic fringe jump corrector (AFJC) circuit has been developed to compensate for fringe jumps. The AFJC can correct phase jumps automatically in real-time. The AFJC, which is integrated on one chip, is installed on the presently working phase counter circuit. As for the specification of this phase counter the intermediate beat signal is 1 MHz, the phase detection range is 31 fringes with phase resolution of 1/80 of a fringe and the response time of 10 μs. The circuit has been tested on the far infrared (FIR) laser interferometer on LHD. The AFJC works fine to correct fringe jumps, when fringe jumps occurred due to the strong density gradient produced by the hydrogen pellet injection

  13. Quick-start of full-scale anaerobic digestion (AD) using aeration

    Energy Technology Data Exchange (ETDEWEB)

    Lagerkvist, Anders, E-mail: al@ltu.se; Pelkonen, Markku; Wikström, Tommy

    2015-04-15

    Highlights: • A fast, and original, start up procedure for anaerobic digestors has been applied at full scale. • The development of a methanogenic culture has been documented using fluorescent in situ hybridization. • The technique can be widely applied. - Abstract: A conventional 1300 m{sup 3} continuously stirred anaerobic tank reactor at the city of Boden, north Sweden, which was receiving a feed of both sewage sludge and food waste, was put out of operation due to the build-up of a float phase. The reactor was emptied and cleaned. At start-up there was no methanogenic sludge available, so an unconventional start-up procedure was applied: The reactor was rapidly (8 days with 1200 kg of total solids (TS) added daily) filled with thickened, and slightly acidic sewage sludge, showing only slight methane generation, which was subsequently heated to 55 °C. Then compressed air was blown into the digester and within a month a fully functional methanogenic culture was established. The transfer from acidogenic to methanogenic conditions happened in about one week. As a start-up technique this is fast and cost efficient, it only requires the access of a compressor, electricity and a source of air. In total, about 16 tonnes of oxygen were used. It is proposed that this method may also be used as an operational amendment technique, should a reactor tend to acidify.

  14. Quick-start of full-scale anaerobic digestion (AD) using aeration

    International Nuclear Information System (INIS)

    Lagerkvist, Anders; Pelkonen, Markku; Wikström, Tommy

    2015-01-01

    Highlights: • A fast, and original, start up procedure for anaerobic digestors has been applied at full scale. • The development of a methanogenic culture has been documented using fluorescent in situ hybridization. • The technique can be widely applied. - Abstract: A conventional 1300 m 3 continuously stirred anaerobic tank reactor at the city of Boden, north Sweden, which was receiving a feed of both sewage sludge and food waste, was put out of operation due to the build-up of a float phase. The reactor was emptied and cleaned. At start-up there was no methanogenic sludge available, so an unconventional start-up procedure was applied: The reactor was rapidly (8 days with 1200 kg of total solids (TS) added daily) filled with thickened, and slightly acidic sewage sludge, showing only slight methane generation, which was subsequently heated to 55 °C. Then compressed air was blown into the digester and within a month a fully functional methanogenic culture was established. The transfer from acidogenic to methanogenic conditions happened in about one week. As a start-up technique this is fast and cost efficient, it only requires the access of a compressor, electricity and a source of air. In total, about 16 tonnes of oxygen were used. It is proposed that this method may also be used as an operational amendment technique, should a reactor tend to acidify

  15. An investigation of time-frequency domain phase-weighted stacking and its application to phase-velocity extraction from ambient noise's empirical Green's functions

    Science.gov (United States)

    Li, Guoliang; Niu, Fenglin; Yang, Yingjie; Xie, Jun

    2018-02-01

    The time-frequency domain phase-weighted stacking (tf-PWS) technique based on the S transform has been employed in stacking empirical Green's functions (EGFs) derived from ambient noise data, mainly due to its superior power in enhancing weak signals. Questions such as the induced waveform distortion and the feasibility of phase-velocity extraction are yet to be thoroughly explored. In this study, we investigate these issues by conducting extensive numerical tests with both synthetic data and USArray transportable array (TA) ambient noise data. We find that the errors in the measured phase velocities associated with waveform distortion caused by the tf-PWS depend largely on the way of how the inverse S transform (IST) is implemented. If frequency IST is employed in tf-PWS, the corresponding errors are generally less than 0.1 per cent, sufficiently small that the measured phase velocities can be safely used in regular surface wave tomography. On the other hand, if a time IST is used in tf-PWS, then the extracted phase velocities are systematically larger than those measured from linearly stacked ones, and the discrepancy can reach as much as ˜0.4 per cent at some periods. Therefore, if tf-PWS is used in stacking EGFs, then frequency IST is preferred to transform the stacked S spectra back to the time domain for the stacked EGFs.

  16. Quantum dynamical time evolutions as stochastic flows on phase space

    International Nuclear Information System (INIS)

    Combe, P.; Rodriguez, R.; Guerra, F.; Sirigue, M.; Sirigue-Collin, M.

    1984-01-01

    We are mainly interested in describing the time development of the Wigner functions by means of stochastic processes. In the second section we recall the main properties of the Wigner functions as well as those of their Fourier transform. In the next one we derive the evolution equation of these functions for a class of Hamiltonians and we give a probabilistic expression for the solution of these equations by means of a stochastic flow in phase space which reminds of the classical flows. In the last section we remark that the previously defined flow can be extended to the bounded continuous functions on phase space and that this flow conserves the cone generated by the Wigner functions. (orig./HSI)

  17. Real-time interferometer phase detection using an LSI-11 microcomputer and high-speed digital techniques

    International Nuclear Information System (INIS)

    Mendell, D.S.

    1978-01-01

    This paper describes the basic design and philosophy of a real-time, interferometer phase-detection system used on the 2XIIB and TMX magnetic-fusion experiments at the Lawrence Livermore Laboratory. This diagnostics system is now a satellite to a host computer and uses high-speed, emitter-coupled logic techniques to derive data on real-time phase relationships. The system's input signals can be derived from interferometer outputs over a wide range of reference frequencies. An LSI-11 microcomputer is the interface between the high-speed phase-detection logic, buffer memory, human interaction, and host computer. Phase data on a storage CRT is immediately displayed after each experimental fusion shot. An operator can interrogate this phase data more closely from an interactive control panel, while the host computer is simultaneously examining the system's buffer memory or arming the system for the next shot

  18. Mesoscopic structural phase progression in photo-excited VO2 revealed by time-resolved x-ray diffraction microscopy

    Science.gov (United States)

    Zhu, Yi; Cai, Zhonghou; Chen, Pice; Zhang, Qingteng; Highland, Matthew J.; Jung, Il Woong; Walko, Donald A.; Dufresne, Eric M.; Jeong, Jaewoo; Samant, Mahesh G.; Parkin, Stuart S. P.; Freeland, John W.; Evans, Paul G.; Wen, Haidan

    2016-02-01

    Dynamical phase separation during a solid-solid phase transition poses a challenge for understanding the fundamental processes in correlated materials. Critical information underlying a phase transition, such as localized phase competition, is difficult to reveal by measurements that are spatially averaged over many phase separated regions. The ability to simultaneously track the spatial and temporal evolution of such systems is essential to understanding mesoscopic processes during a phase transition. Using state-of-the-art time-resolved hard x-ray diffraction microscopy, we directly visualize the structural phase progression in a VO2 film upon photoexcitation. Following a homogenous in-plane optical excitation, the phase transformation is initiated at discrete sites and completed by the growth of one lattice structure into the other, instead of a simultaneous isotropic lattice symmetry change. The time-dependent x-ray diffraction spatial maps show that the in-plane phase progression in laser-superheated VO2 is via a displacive lattice transformation as a result of relaxation from an excited monoclinic phase into a rutile phase. The speed of the phase front progression is quantitatively measured, and is faster than the process driven by in-plane thermal diffusion but slower than the sound speed in VO2. The direct visualization of localized structural changes in the time domain opens a new avenue to study mesoscopic processes in driven systems.

  19. Sequential processing of quantitative phase images for the study of cell behaviour in real-time digital holographic microscopy.

    Science.gov (United States)

    Zikmund, T; Kvasnica, L; Týč, M; Křížová, A; Colláková, J; Chmelík, R

    2014-11-01

    Transmitted light holographic microscopy is particularly used for quantitative phase imaging of transparent microscopic objects such as living cells. The study of the cell is based on extraction of the dynamic data on cell behaviour from the time-lapse sequence of the phase images. However, the phase images are affected by the phase aberrations that make the analysis particularly difficult. This is because the phase deformation is prone to change during long-term experiments. Here, we present a novel algorithm for sequential processing of living cells phase images in a time-lapse sequence. The algorithm compensates for the deformation of a phase image using weighted least-squares surface fitting. Moreover, it identifies and segments the individual cells in the phase image. All these procedures are performed automatically and applied immediately after obtaining every single phase image. This property of the algorithm is important for real-time cell quantitative phase imaging and instantaneous control of the course of the experiment by playback of the recorded sequence up to actual time. Such operator's intervention is a forerunner of process automation derived from image analysis. The efficiency of the propounded algorithm is demonstrated on images of rat fibrosarcoma cells using an off-axis holographic microscope. © 2014 The Authors Journal of Microscopy © 2014 Royal Microscopical Society.

  20. Design Methodology of Camshaft Driven Charge Valves for Pneumatic Engine Starts

    Directory of Open Access Journals (Sweden)

    Moser Michael M.

    2015-01-01

    Full Text Available Idling losses constitute a significant amount of the fuel consumption of internal combustion engines. Therefore, shutting down the engine during idling phases can improve its overall efficiency. For driver acceptance a fast restart of the engine must be guaranteed. A fast engine start can be performed using a powerful electric starter and an appropriate battery which are found in hybrid electric vehicles, for example. However, these devices involve additional cost and weight. An alternative method is to use a tank with pressurized air that can be injected directly into the cylinders to start the engine pneumatically. In this paper, pneumatic engine starts using camshaft driven charge valves are discussed. A general methodology for an air-optimal charge valve design is presented which can deal with various requirements. The proposed design methodology is based on a process model representing pneumatic engine operation. A design example for a two-cylinder engine is shown, and the resulting optimized pneumatic start is experimentally verified on a test bench engine. The engine’s idling speed of 1200 rpm can be reached within 350 ms for an initial pressure in the air tank of 10 bar. A detailed system analysis highlights the characteristics of the optimal design found.

  1. From START to NEW START. The dilemma and future of nuclear disarmament

    International Nuclear Information System (INIS)

    Plettenberg, Lars

    2012-01-01

    The report describes the existing four agreements on nuclear disarmament: START I (1991). START II (1993), SORT (2002) and NEW START (2010). The chapter on the dependence between nuclear disarmament and strategic stability covers the issues mutual assured destruction (MAD), credibility, overkill capacity; the role of nuclear weapons in the national strategies of the USA and NATO, Russia, Great Britain, France, China and the other nuclear states. Ways out of MAD include disarmament, de-alerting and mutual assured protection (MAP).

  2. Modelling and Predicting Backstroke Start Performance Using Non-Linear and Linear Models.

    Science.gov (United States)

    de Jesus, Karla; Ayala, Helon V H; de Jesus, Kelly; Coelho, Leandro Dos S; Medeiros, Alexandre I A; Abraldes, José A; Vaz, Mário A P; Fernandes, Ricardo J; Vilas-Boas, João Paulo

    2018-03-01

    Our aim was to compare non-linear and linear mathematical model responses for backstroke start performance prediction. Ten swimmers randomly completed eight 15 m backstroke starts with feet over the wedge, four with hands on the highest horizontal and four on the vertical handgrip. Swimmers were videotaped using a dual media camera set-up, with the starts being performed over an instrumented block with four force plates. Artificial neural networks were applied to predict 5 m start time using kinematic and kinetic variables and to determine the accuracy of the mean absolute percentage error. Artificial neural networks predicted start time more robustly than the linear model with respect to changing training to the validation dataset for the vertical handgrip (3.95 ± 1.67 vs. 5.92 ± 3.27%). Artificial neural networks obtained a smaller mean absolute percentage error than the linear model in the horizontal (0.43 ± 0.19 vs. 0.98 ± 0.19%) and vertical handgrip (0.45 ± 0.19 vs. 1.38 ± 0.30%) using all input data. The best artificial neural network validation revealed a smaller mean absolute error than the linear model for the horizontal (0.007 vs. 0.04 s) and vertical handgrip (0.01 vs. 0.03 s). Artificial neural networks should be used for backstroke 5 m start time prediction due to the quite small differences among the elite level performances.

  3. Random Start Ovarian Stimulation for Oocyte or Embryo Cryopreservation in Women Desiring Fertility Preservation Prior to Gonadotoxic Cancer Therapy.

    Science.gov (United States)

    Danis, Rachel B; Pereira, Nigel; Elias, Rony T

    2017-11-10

    Women of reproductive age diagnosed with cancer are often interested in preserving gametes or reproductive tissue that would allow for future genetic parenthood. Preservation of fertility is often accomplished in young cancer patients via ovarian stimulation followed by oocyte or embryo cryopreservation. Conventional stimulation protocols, however, require 2-4 weeks to complete ovarian stimulation, oocyte retrieval and possible fertilization. Such a strategy may not be feasible in patients requiring urgent cancer treatment. Recent studies have highlighted that random start ovarian stimulation can be initiated irrespective of the phase of the menstrual cycle and is an attractive alternative to conventional ovarian stimulation. The primary aim of the current review is to discuss the feasibility and success of random start ovarian stimulation for oocyte or embryo cryopreservation in women desiring fertility preservation prior to gonadotoxic cancer therapy. We performed a systematic review of medical literature published between January 2000 to June 2017 reporting the utility of random start ovarian stimulation for fertility preservation. Search terms included "fertility preservation," "cancer," "ovarian stimulation," "random-start ovarian stimulation," "embryo cryopreservation, and" "oocyte cryopreservation." Publications were included in this review only if patients underwent random start ovarian stimulation prior to cancer therapy. Nineteen publications were identified and perused by the authors. Most publications described the utility of random start ovarian stimulation in the setting of breast cancer. Radom-start stimulation was associated with a reduced time interval between ovarian stimulation initiation and oocyte or embryo cryopreservation. The yield of mature oocytes and their developmental potential into embryos was comparable between conventional and random-start protocols, albeit with higher gonadotropin doses in the latter. The current review suggests

  4. Getting Started with Processing

    CERN Document Server

    Reas, Casey

    2010-01-01

    Learn computer programming the easy way with Processing, a simple language that lets you use code to create drawings, animation, and interactive graphics. Programming courses usually start with theory, but this book lets you jump right into creative and fun projects. It's ideal for anyone who wants to learn basic programming, and serves as a simple introduction to graphics for people with some programming skills. Written by the founders of Processing, this book takes you through the learning process one step at a time to help you grasp core programming concepts. You'll learn how to sketch wi

  5. Task-related increases in fatigue predict recovery time after academic stress.

    Science.gov (United States)

    Blasche, Gerhard; Zilic, Jelena; Frischenschlager, Oskar

    2016-01-01

    The aim of this study was to investigate the time course of recovery after an academic exam as a model of high workload and its association with stress-related fatigue. Thirty-six medical students (17 females, 19 males) filled out diaries during an exam phase, starting 2 days prior to the exam, and a control phase 4 weeks after the exam for 14 days, respectively. Fatigue, distress, quality of sleep, and health complaints were assessed. Recovery time was determined for each individual and variable by comparing the 3-day average with the confidence interval of the control phase. Recovery time was predicted by Cox regression analyses. Recovery times of all variables except health complaints were predicted by stress-related fatigue. Half of the individuals had recovered after 6 days, and 80% of the individuals had recovered after 8 days. The time necessary for recovery from work demands is determined by fatigue as a measure of resource depletion.

  6. An energy-stable time-integrator for phase-field models

    KAUST Repository

    Vignal, Philippe

    2016-12-27

    We introduce a provably energy-stable time-integration method for general classes of phase-field models with polynomial potentials. We demonstrate how Taylor series expansions of the nonlinear terms present in the partial differential equations of these models can lead to expressions that guarantee energy-stability implicitly, which are second-order accurate in time. The spatial discretization relies on a mixed finite element formulation and isogeometric analysis. We also propose an adaptive time-stepping discretization that relies on a first-order backward approximation to give an error-estimator. This error estimator is accurate, robust, and does not require the computation of extra solutions to estimate the error. This methodology can be applied to any second-order accurate time-integration scheme. We present numerical examples in two and three spatial dimensions, which confirm the stability and robustness of the method. The implementation of the numerical schemes is done in PetIGA, a high-performance isogeometric analysis framework.

  7. An energy-stable time-integrator for phase-field models

    KAUST Repository

    Vignal, Philippe; Collier, N.; Dalcin, Lisandro; Brown, D.L.; Calo, V.M.

    2016-01-01

    We introduce a provably energy-stable time-integration method for general classes of phase-field models with polynomial potentials. We demonstrate how Taylor series expansions of the nonlinear terms present in the partial differential equations of these models can lead to expressions that guarantee energy-stability implicitly, which are second-order accurate in time. The spatial discretization relies on a mixed finite element formulation and isogeometric analysis. We also propose an adaptive time-stepping discretization that relies on a first-order backward approximation to give an error-estimator. This error estimator is accurate, robust, and does not require the computation of extra solutions to estimate the error. This methodology can be applied to any second-order accurate time-integration scheme. We present numerical examples in two and three spatial dimensions, which confirm the stability and robustness of the method. The implementation of the numerical schemes is done in PetIGA, a high-performance isogeometric analysis framework.

  8. Automatic start-up system of nuclear reactor based on sequence control technology

    International Nuclear Information System (INIS)

    Zhang Yao; Zhang Dafa; Peng Huaqing

    2009-01-01

    A conceptive design of an automatic start-up system based on the sequence control for the nuclear reactors is given in this paper, so as to solve the problems during the start-up process, such as the long operation time, low automatic control level and high accident rate. The start-up process and its requirements are analyzed in detail at first. Then,the principle, the architecture, the key technologies of the automatic start-up system of nuclear reactors are designed and discussed. With the designed system, the automatic start-up of the nuclear reactor can be realized,the work load of the operator can be reduced,and the safety and efficiency of the nuclear power plant during its start-up can be improved. (authors)

  9. Development of a high-throughput real time PCR based on a hot-start alternative for Pfu mediated by quantum dots

    Science.gov (United States)

    Sang, Fuming; Yang, Yang; Yuan, Lin; Ren, Jicun; Zhang, Zhizhou

    2015-09-01

    Hot start (HS) PCR is an excellent alternative for high-throughput real time PCR due to its ability to prevent nonspecific amplification at low temperature. Development of a cost-effective and simple HS PCR technique to guarantee high-throughput PCR specificity and consistency still remains a great challenge. In this study, we systematically investigated the HS characteristics of QDs triggered in real time PCR with EvaGreen and SYBR Green I dyes by the analysis of amplification curves, standard curves and melting curves. Two different kinds of DNA polymerases, Pfu and Taq, were employed. Here we showed that high specificity and efficiency of real time PCR were obtained in a plasmid DNA and an error-prone two-round PCR assay using QD-based HS PCR, even after an hour preincubation at 50 °C before real time PCR. Moreover, the results obtained by QD-based HS PCR were comparable to a commercial Taq antibody DNA polymerase. However, no obvious HS effect of QDs was found in real time PCR using Taq DNA polymerase. The findings of this study demonstrated that a cost-effective high-throughput real time PCR based on QD triggered HS PCR could be established with high consistency, sensitivity and accuracy.Hot start (HS) PCR is an excellent alternative for high-throughput real time PCR due to its ability to prevent nonspecific amplification at low temperature. Development of a cost-effective and simple HS PCR technique to guarantee high-throughput PCR specificity and consistency still remains a great challenge. In this study, we systematically investigated the HS characteristics of QDs triggered in real time PCR with EvaGreen and SYBR Green I dyes by the analysis of amplification curves, standard curves and melting curves. Two different kinds of DNA polymerases, Pfu and Taq, were employed. Here we showed that high specificity and efficiency of real time PCR were obtained in a plasmid DNA and an error-prone two-round PCR assay using QD-based HS PCR, even after an hour

  10. PBFA [Particle Beam Fusion Accelerator] II: The pulsed power characterization phase

    International Nuclear Information System (INIS)

    Martin, T.H.; Turman, B.N.; Goldstein, S.A.

    1987-01-01

    The Particle Beam Fusion Accelerator II, PBFA II, is now the largest pulsed power device in operation. This paper summarizes its first year and a half of operation for the Department of Energy (DOE) Inertial Confinement Fusion (ICF) program. Thirty-six separate modules provide 72 output pulses that combine to form a 100 TW output pulse at the accelerator center. PBFA II was successfully test fired for the first time on December 11, 1985. This test completed the construction phase (Phase 1) within the expected schedule and budget. The accelerator checkout phase then started (Phase 2). The first priority during checkout was to bring the Phase 1 subsystems into full operation. The accelerator was first tested to determine overall system performance. Next, subsystems that were not performing adequately were modified. The accelerator is now being used for ion diode studies. 32 refs

  11. Multiphase flows with phase change

    Indian Academy of Sciences (India)

    Multiphase flows with phase change are ubiquitous in many industrial sectors ranging from energy and infra-structure to specialty chemicals and pharmaceuticals. My own interest in mul- tiphase flows with phase change started more than 15 years ago when I had initiated work on riser reactor for fluid catalytic cracking and ...

  12. Association of blood pressure with decline in renal function and time until the start of renal replacement therapy in pre-dialysis patients: a cohort study

    Directory of Open Access Journals (Sweden)

    Sijpkens Yvo WJ

    2011-08-01

    Full Text Available Abstract Background To investigate whether high blood pressure accelerates renal function decline in patients with advanced chronic kidney disease (CKD, we studied the association of systolic (SBP and diastolic blood pressure (DBP with decline in renal function and time until the start of renal replacement therapy (RRT in patients with CKD stages IV-V on pre-dialysis care. Methods In the PREPARE-1 cohort 547 incident pre-dialysis patients, referred as part of the usual care to outpatient clinics of eight Dutch hospitals, were included between 1999 and 2001 and followed until the start of RRT, mortality, or end of follow-up (January 1st 2008. Main outcomes were rate of decline in renal function, estimated as the slope of available eGFR measurements, and time until the start of RRT. Results A total of 508 patients, 57% men and median (IQR age of 63 (50-73 years, were available for analyses. Mean (SD decline in renal function was 0.35 (0.75 ml/min/1.73 m2/month. Every 10 mmHg increase in SBP or DBP resulted in an accelerated decline in renal function (adjusted additional decline 0.04 (0.02;0.07 and 0.05 (0.00;0.11 ml/min/1.73 m2/month respectively and an earlier start of RRT (adjusted HR 1.09 (1.04;1.14 and 1.16 (1.05;1.28 respectively. Furthermore, patients with SBP and DBP above the BP target goal of 2/month and an earlier start of RRT (adjusted HR 2.08 (1.25;3.44, compared to patients who achieved the target goal (11%. Comparing the decline in renal function and risk of starting RRT between patients with only SBP above the target (≥ 130 mmHg and patients with both SBP and DBP below the target (2/month and adjusted HR 2.24 (1.26;3.97. Therefore, it seems that especially having SBP above the target is harmful. Conclusions In pre-dialysis patients with CKD stages IV-V, having blood pressure (especially SBP above the target goal for CKD patients (

  13. Phase Startup Initiative Phases 3 and 4 Test Plan and Test Specification ( OCRWM)

    Energy Technology Data Exchange (ETDEWEB)

    PAJUNEN, A.L.; LANGEVIN, M.J.

    2000-08-07

    Construction for the Spent Nuclear Fuel (SNF) Project facilities is continuing per the Level III Baseline Schedule, and installation of the Fuel Retrieval System (FRS) and Integrated Water Treatment System (IWTS) in K West Basin is now complete. In order to accelerate the project, a phased start up strategy to initiate testing of the FRS and IWTS early in the overall project schedule was proposed (Williams 1999). Wilkinson (1999) expands the definition of the original proposal into four functional testing phases of the Phased Startup Initiative (PSI). Phases 1 and 2 are based on performing functional tests using dummy fuel. This test plan provides overall guidance for Phase 3 and 4 tests, which are performed using actual irradiated N fuel assemblies. The overall objective of the Phase 3 and 4 testing is to verify how the FRS and IWTS respond while processing actual fuel. Conducting these tests early in the project schedule will allow identification and resolution of equipment and process problems before they become activities on the start-up critical path. The specific objectives of this test plan are to: Define the Phase 3 and 4 test scope for the FRS and IWTS; Provide detailed test requirements that can be used to write the specific test procedures; Define data required and measurements to be taken. Where existing methods to obtain these do not exist, enough detail will be provided to define required additional equipment; and Define specific test objectives and acceptance criteria.

  14. Phase Startup Initiative Phases 3 and 4 Test Plan and Test Specification (OCRWM)

    International Nuclear Information System (INIS)

    PAJUNEN, A.L.; LANGEVIN, M.J.

    2000-01-01

    Construction for the Spent Nuclear Fuel (SNF) Project facilities is continuing per the Level III Baseline Schedule, and installation of the Fuel Retrieval System (FRS) and Integrated Water Treatment System (IWTS) in K West Basin is now complete. In order to accelerate the project, a phased start up strategy to initiate testing of the FRS and IWTS early in the overall project schedule was proposed (Williams 1999). Wilkinson (1999) expands the definition of the original proposal into four functional testing phases of the Phased Startup Initiative (PSI). Phases 1 and 2 are based on performing functional tests using dummy fuel. This test plan provides overall guidance for Phase 3 and 4 tests, which are performed using actual irradiated N fuel assemblies. The overall objective of the Phase 3 and 4 testing is to verify how the FRS and IWTS respond while processing actual fuel. Conducting these tests early in the project schedule will allow identification and resolution of equipment and process problems before they become activities on the start-up critical path. The specific objectives of this test plan are to: Define the Phase 3 and 4 test scope for the FRS and IWTS; Provide detailed test requirements that can be used to write the specific test procedures; Define data required and measurements to be taken. Where existing methods to obtain these do not exist, enough detail will be provided to define required additional equipment; and Define specific test objectives and acceptance criteria

  15. Time-resolved computed tomography of the liver: retrospective, multi-phase image reconstruction derived from volumetric perfusion imaging

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, Michael A.; Kartalis, Nikolaos; Aspelin, Peter; Albiin, Nils; Brismar, Torkel B. [Karolinska University Hospital, Division of Medical Imaging and Technology, Department of Clinical Science, Intervention and Technology (CLINTEC), Karolinska Institutet, Stockholm (Sweden); Leidner, Bertil; Svensson, Anders [Karolinska University Hospital, Division of Medical Imaging and Technology, Department of Clinical Science, Intervention and Technology (CLINTEC), Karolinska Institutet, Stockholm (Sweden); Karolinska University Hospital Huddinge, Department of Radiology, Stockholm (Sweden)

    2014-01-15

    To assess feasibility and image quality (IQ) of a new post-processing algorithm for retrospective extraction of an optimised multi-phase CT (time-resolved CT) of the liver from volumetric perfusion imaging. Sixteen patients underwent clinically indicated perfusion CT using 4D spiral mode of dual-source 128-slice CT. Three image sets were reconstructed: motion-corrected and noise-reduced (MCNR) images derived from 4D raw data; maximum and average intensity projections (time MIP/AVG) of the arterial/portal/portal-venous phases and all phases (total MIP/ AVG) derived from retrospective fusion of dedicated MCNR split series. Two readers assessed the IQ, detection rate and evaluation time; one reader assessed image noise and lesion-to-liver contrast. Time-resolved CT was feasible in all patients. Each post-processing step yielded a significant reduction of image noise and evaluation time, maintaining lesion-to-liver contrast. Time MIPs/AVGs showed the highest overall IQ without relevant motion artefacts and best depiction of arterial and portal/portal-venous phases respectively. Time MIPs demonstrated a significantly higher detection rate for arterialised liver lesions than total MIPs/AVGs and the raw data series. Time-resolved CT allows data from volumetric perfusion imaging to be condensed into an optimised multi-phase liver CT, yielding a superior IQ and higher detection rate for arterialised liver lesions than the raw data series. (orig.)

  16. Saccadic reaction times to audiovisual stimuli show effects of oscillatory phase reset.

    Directory of Open Access Journals (Sweden)

    Adele Diederich

    Full Text Available Initiating an eye movement towards a suddenly appearing visual target is faster when an accessory auditory stimulus occurs in close spatiotemporal vicinity. Such facilitation of saccadic reaction time (SRT is well-documented, but the exact neural mechanisms underlying the crossmodal effect remain to be elucidated. From EEG/MEG studies it has been hypothesized that coupled oscillatory activity in primary sensory cortices regulates multisensory processing. Specifically, it is assumed that the phase of an ongoing neural oscillation is shifted due to the occurrence of a sensory stimulus so that, across trials, phase values become highly consistent (phase reset. If one can identify the phase an oscillation is reset to, it is possible to predict when temporal windows of high and low excitability will occur. However, in behavioral experiments the pre-stimulus phase will be different on successive repetitions of the experimental trial, and average performance over many trials will show no signs of the modulation. Here we circumvent this problem by repeatedly presenting an auditory accessory stimulus followed by a visual target stimulus with a temporal delay varied in steps of 2 ms. Performing a discrete time series analysis on SRT as a function of the delay, we provide statistical evidence for the existence of distinct peak spectral components in the power spectrum. These frequencies, although varying across participants, fall within the beta and gamma range (20 to 40 Hz of neural oscillatory activity observed in neurophysiological studies of multisensory integration. Some evidence for high-theta/alpha activity was found as well. Our results are consistent with the phase reset hypothesis and demonstrate that it is amenable to testing by purely psychophysical methods. Thus, any theory of multisensory processes that connects specific brain states with patterns of saccadic responses should be able to account for traces of oscillatory activity in observable

  17. Phase-Space Manipulation of Ultracold Ion Bunches with Time-Dependent Fields

    International Nuclear Information System (INIS)

    Reijnders, M. P.; Debernardi, N.; Geer, S. B. van der; Mutsaers, P. H. A.; Vredenbregt, E. J. D.; Luiten, O. J.

    2010-01-01

    All applications of high brightness ion beams depend on the possibility to precisely manipulate the trajectories of the ions or, more generally, to control their phase-space distribution. We show that the combination of a laser-cooled ion source and time-dependent acceleration fields gives new possibilities to perform precise phase-space control. We demonstrate reduction of the longitudinal energy spread and realization of a lens with control over its focal length and sign, as well as the sign of the spherical aberrations. This creates new possibilities to correct for the spherical and chromatic aberrations which are presently limiting the spatial resolution.

  18. Influence of decrease of the amount of starting salary of radiological technologists

    International Nuclear Information System (INIS)

    Shibuya, Koichi; Kato, Hirokazu

    2010-01-01

    This paper analyzes differences and changes within and between the occupation of nurses, radiological technologists, and medical technologists concerning starting salary from April 2005 to March 2009. This paper also investigates the percentage of difference in the amount of starting salary of nurses, radiological technologists, and medical technologists according to their educational attainments. The research-target used was the full-time-job-opening data provided to Okayama University within the given period of time, which specifies the amount of starting salary. The result shows that one's educational background has a crucial influence on the amount of one's starting salary. In fact, the percentage of the amount of starting salary base on one's educational attainment all increased in nurses, radiological technologists, and medical technologists from April 2007 to March 2009. However, this percentage for radiological technologists remains only 50% of increase, which was less significant than other two professional occupations. Moreover, the result indicates a crucial change in the amount of basic starting salary: while the amount of basic starting salary of nurses in 2008 has increased since 2005, that of radiological technologists has dropped remarkably. If this situation is not improved in the near future, the health-service sector may experience a decrease in the number of skilled practitioners which, in turn, will result in a decline in quality of medical care. (author)

  19. Three-dimensional real-time synthetic aperture imaging using a rotating phased array transducer

    DEFF Research Database (Denmark)

    Nikolov, Svetoslav; Dufait, Remi; Schoisswohl, Armin

    2002-01-01

    phased array, which is rotated over the volume of interest. The data is acquired using coded signals and synthetic transmit aperture imaging. Only one group of elements transmits at a time. The delays are set such as to form a cylindrical wave. The back-scattered signal carries information not only from......Current 3D real-time imaging is done either with sparse 2D arrays, or with mechanically moved phased arrays. The former results in a poor resolution and contrast due to a limited amount of elements. The latter has the disadvantage of low frame rates due to the sequential acquisition of the volume...... line-by-line and plane-by-plane. This paper describes an approach which combines mechanically moved phased array with synthetic transmit aperture imaging, resulting in high volume acquisition rates without a trade-off in image quality. The scan method uses a conventional fully populated 64 element...

  20. Managing Bioplastics Business Innovation in Start Up Phase

    Directory of Open Access Journals (Sweden)

    Pornpun Theinsathid

    2009-05-01

    Full Text Available Fostering innovation in a mature company can often seem like a swim upstream—the needs of the existing business often overwhelm attempts to create something new. Mature companies understand that to compete today they need to innovate. But finding sources of innovation while still paying attention to the current business can be a struggle. Open innovation has played an important role to drive the new business in 21th century. Academic research commercialization may be challenged by the faculty members’ academic routines, institutional priorities, and faculty retention. In order to undertake applied research, university scientists must spend a certain amount of time each period to keep up with the latest scientific developments and absorb new ideas. Because almost all faculty members have teaching responsibilities, many of them fear that participation in the protection and commercialization of Intellectual Property Rights is time consuming. There are lots of basic researches focuses on polylactic acid (PLA, the most promising bioplastics, however that is still far behind the commercialization step. The close innovation system may take longer time to achieve excellence in its technology under fierce competition environment. This study illuminates the complexities and challenges involved in managing innovation toward specific results. These challenges seem to result, in part, from the multidisciplinary nature of R&D work, it associated with risks, uncertainty and non-linear processes. One of the finding in this study is that many of the factors that drive innovative bioplastic industry are derived in collaboration with technology push and demand pull. The study’s findings contribute to our understanding of consumer attitudes towards ‘Green’ products such as bioplastics. Most critical in this respect is whether such products make economic sense for a company. This study may provide some guidelines to support development of a concrete

  1. Wave packet dynamics, time scales and phase diagram in the IBM-Lipkin-Meshkov-Glick model

    Science.gov (United States)

    Castaños, Octavio; de los Santos, Francisco; Yáñez, Rafael; Romera, Elvira

    2018-02-01

    We derive the phase diagram of a scalar two-level boson model by studying the equilibrium and stability properties of its energy surface. The plane of control parameters is enlarged with respect to previous studies. We then analyze the time evolution of wave packets centered around the ground state at various quantum phase transition boundary lines. In particular, classical and revival times are computed numerically.

  2. Classicalization times of parametrically amplified 'Schroedinger cat' states coupled to phase-sensitive reservoirs

    International Nuclear Information System (INIS)

    Dodonov, V.V.; Valverde, C.; Souza, L.S.; Baseia, B.

    2011-01-01

    The exact Wigner function of a parametrically excited quantum oscillator in a phase-sensitive amplifying/attenuating reservoir is found for initial even/odd coherent states. Studying the evolution of negativity of the Wigner function we show the difference between the 'initial positivization time' (IPT), which is inversely proportional to the square of the initial size of the superposition, and the 'final positivization time' (FPT), which does not depend on this size. Both these times can be made arbitrarily long in maximally squeezed high-temperature reservoirs. Besides, we find the conditions when some (small) squeezing can exist even after the Wigner function becomes totally positive. -- Highlights: → We study parametric excitation of a quantum oscillator in phase-sensitive baths. → Exact time-dependent Wigner function for initial even/odd coherent states is found. → The evolution of negativity of Wigner function is compared with the squeezing dynamics. → The difference between initial and final 'classicalization times' is emphasized. → Both these times can be arbitrarily long for rigged reservoirs at infinite temperature.

  3. Lean and global technology start-ups

    DEFF Research Database (Denmark)

    Tanev, Stoyan; Rasmussen, Erik Stavnsager; Zijdemans, Erik

    2015-01-01

    In this paper the authors introduce the concept of Lean Global Start-up (LGS) as a way of emphasizing the impossibility for new technology start-ups to deal separately with business development, innovation and early internationalization. For a newly established technology firm the task of being...... global and innovative at the same time should be seen as one process. The paper has two components – an introductory conceptual part and an empirical part that should be considered as basis for the preliminary validation of the conceptual insights. The research sample includes six firms – three from...... Canada and three from Denmark. The firms have had significant problems with the complexity, uncertainties and risks of being innovative on a global scale. They have however found ways of addressing these problems by a disciplined knowledge sharing and IP protection strategy and the efficient use...

  4. Secondary Circuit Start Up Chemistry Optimisation

    International Nuclear Information System (INIS)

    Fontan, Guillaume; Morel, Pascal

    2012-09-01

    In a context of investment and renewal of equipment, Electricite De France (EDF) put enhanced efforts on operating practices during start-up of the secondary circuit, in order to improve operational performance and materials lifetime. This article focuses on the objective of optimizing the filling, the chemical conditioning and the thermal conditioning of the secondary fluid, while taking into account the following issues: - Limiting the time required to obtain a proper chemistry, - Limiting the amount of water and steam used, - Limiting the amount of effluent generated. The scope is all start-up conditions of secondary circuit, both after refuelling outage or fortuitous shutdowns of the plant. The recommendations produced are based on existing local procedures and good practices, which were collected and developed in order to propose a generic methodology understandable and useful both for operators, chemists and managers. (authors)

  5. SuperJet International case study: a business network start-up in the aeronautics industry

    Science.gov (United States)

    Corallo, Angelo; de Maggio, Marco; Storelli, Davide

    This chapter presents the SuperJet International case study, a start-up in the aeronautics industry characterized by a process-oriented approach and a complex and as yet evolving network of partnerships and collaborations. The chapter aims to describe the key points of the start-up process, highlighting common factors and differences compared to the TEKNE Methodology of Change, with particular reference to the second and third phase, namely, the design and deployment of new techno-organizational systems. The SuperJet International startup is presented as a case study where strategic and organizational aspects have been jointly conceived from a network-driven perspective. The chapter compares some of the guidelines of the TEKNE Methodology of Change with experiences and actual practices deriving from interviews with key players in SJI's start-up process.

  6. Experimental study on the start-up with dry gases from normal cell temperatures in self-humidified proton exchange membrane fuel cells

    International Nuclear Information System (INIS)

    Kong, Im Mo; Jung, Aeri; Kim, Beom Jun; Baik, Kyung Don; Kim, Min Soo

    2015-01-01

    In this study, the start-up characteristics of PEMFCs (proton exchange membrane fuel cells) was investigated with dry gases from normal cell temperatures above 0 °C. Firstly, the effects of flow arrangements (co-flow and counter-flow) were evaluated at a starting cell temperature of 25 °C. Then, the start-up was successful in both arrangements, but it showed better performance with counter-flow. In addition, the hydrogen concentration was measured and it showed that hydrogen crossover contributes to the membrane hydration and the first phase of dry start-up. However, although the cell temperature rose above 45 °C after start-up form 25 °C with counter-flow arrangement, the restart-up after shut-down failed at a starting cell temperature of 45 °C regardless of flow arrangements. Considering the needs of restart-up, the available starting cell temperature should be improved. For this, after first sub-step of start-up process, relatively low flow rates were maintained to retain produced water without purge so that the membrane can be hydrated sufficiently. With this modified process, denominated as WSP (water storage process) in this study, the dry start-up became successful at a starting cell temperature of 45 °C and the cell performance was remarkably improved especially with counter-flow arrangement. - Highlights: • Start-up with dry gases from normal cell temperatures was investigated. • Counter-flow arrangement showed better performance over co-flow arrangement. • Water is produced by hydrogen crossover and its direct reaction with oxygen at cathode side. • It prevents the membrane dehydration and helps the start-up during the first phase of the process. • Available starting cell temperature and cell performance could be improved with WSP.

  7. Effect of resistivity profile on current decay time of initial phase of current quench in neon-gas-puff inducing disruptions of JT-60U

    Energy Technology Data Exchange (ETDEWEB)

    Kawakami, S.; Ohno, N. [Graduate School of Engineering, Nagoya University, Nagoya 464-8603 (Japan); Shibata, Y.; Isayama, A.; Kawano, Y. [Japan Atomic Energy Agency, Naka 311-0193 (Japan); Watanabe, K. Y. [Graduate School of Engineering, Nagoya University, Nagoya 464-8603 (Japan); National Institute for Fusion Science, Toki 509-5292 (Japan); Takizuka, T. [Graduate School of Engineering, Osaka University, Suita 565-0871 (Japan); Okamoto, M. [Ishikawa National College of Technology, Ishikawa 929-0392 (Japan)

    2013-11-15

    According to an early work [Y. Shibata et al., Nucl. Fusion 50, 025015 (2010)] on the behavior of the plasma current decay in the JT-60U disruptive discharges caused by the radiative collapse with a massive neon-gas-puff, the increase of the internal inductance mainly determined the current decay time of plasma current during the initial phase of current quench. To investigate what determines the increase of the internal inductance, we focus attention on the relationship between the electron temperature (or the resistivity) profile and the time evolution of the current density profile and carry out numerical calculations. As a result, we find the reason of the increase of the internal inductance: The current density profile at the start of the current quench is broader than an expected current density profile in the steady state, which is determined by the temperature (or resistivity) profile. The current density profile evolves into peaked one and the internal inductance is increasing.

  8. School Starting Age and Crime

    DEFF Research Database (Denmark)

    Landersø, Rasmus; Nielsen, Helena Skyt; Simonsen, Marianne

    This paper investigates the effects of school starting age on crime while relying on variation in school starting age induced by administrative rules; we exploit that Danish children typically start first grade in the calendar year they turn seven, which gives rise to a discontinuity in children......’s school starting age. Analyses are carried out using register-based Danish data. We find that higher age at school start lowers the propensity to commit crime, but that this reduction is caused by incapacitation while human capital accumulation is unaffected. Importantly, we also find that the individuals...

  9. Start-Up of FEL Oscillator from Shot Noise

    International Nuclear Information System (INIS)

    Kumar, V.; Krishnagopal, S.; Fawley, W.M.

    2007-01-01

    In free-electron laser (FEL) oscillators, as in self-amplified spontaneous emission (SASE) FELs, the buildup of cavity power starts from shot noise resulting from the discreteness of electronic charge. It is important to do the start-up analysis for the build-up of cavity power in order to fix the macropulse width from the electron accelerator such that the system reaches saturation. In this paper, we use the time-dependent simulation code GINGER [1]to perform this analysis. We present results of this analysis for the parameters of the Compact Ultrafast TErahertz FEL (CUTE-FEL) [2] being built at RRCAT

  10. A cross-cultural comparison of sleep duration between U.S. and Australian adolescents: the effect of school start time, parent-set bedtimes and extracurricular load

    NARCIS (Netherlands)

    Short, M.A.; Gradisar, M.; Lack, L.C.; Wright, H.R.; Dewald, J.F.; Wolfson, A.R.; Carskadon, M.A.

    2013-01-01

    Study Objective. To test whether sleep duration on school nights differs between adolescents in Australia and the United States and, if so, whether this difference is explained by cultural differences in school start time, parental involvement in setting bedtimes, and extracurricular commitments.

  11. Quantum dynamics via a time propagator in Wigner's phase space

    DEFF Research Database (Denmark)

    Grønager, Michael; Henriksen, Niels Engholm

    1995-01-01

    We derive an expression for a short-time phase space propagator. We use it in a new propagation scheme and demonstrate that it works for a Morse potential. The propagation scheme is used to propagate classical distributions which do not obey the Heisenberg uncertainty principle. It is shown that ...... as a part of the sampling function. ©1995 American Institute of Physics....

  12. Nonlinear Optical Spectroscopy in the Time Domain: Studies of Ultrafast Molecular Processes in the Condensed Phase.

    Science.gov (United States)

    Joo, Taiha

    Ultrafast molecular processes in the condensed phase at room temperature are studied in the time domain by four wave mixing spectroscopy. The structure/dynamics of various quantum states can be studied by varying the time ordering of the incident fields, their polarization, their colors, etc. In one, time-resolved coherent Stokes Raman spectroscopy of benzene is investigated at room temperature. The reorientational correlation time of benzene as well as the T_2 time of the nu _1 ring-breathing mode have been measured by using two different polarization geometries. Bohr frequency difference beats have also been resolved between the nu_1 modes of ^ {12}C_6H_6 and ^{12}C_5^{13 }CH_6.. The dephasing dynamics of the nu _1 ring-breathing mode of neat benzene is studied by time-resolved coherent anti-Stokes Raman scattering. Ultrafast time resolution reveals deviation from the conventional exponential decay. The correlation time, tau _{rm c}, and the rms magnitude, Delta, of the Bohr frequency modulation are determined for the process responsible for the vibrational dephasing by Kubo dephasing function analysis. The electronic dephasing of two oxazine dyes in ethylene glycol at room temperature is investigated by photon echo experiments. It was found that at least two stochastic processes are responsible for the observed electronic dephasing. Both fast (homogeneous) and slow (inhomogeneous) dynamics are recovered using Kubo line shape analysis. Moreover, the slow dynamics is found to spectrally diffuse over the inhomogeneous distribution on the time scale around a picosecond. Time-resolved degenerate four wave mixing signal of dyes in a population measurement geometry is reported. The vibrational coherences both in the ground and excited electronic states produced strong oscillations in the signal together with the usual population decay from the excited electronic state. Absolute frequencies and their dephasing times of the vibrational modes at ~590 cm^{-1} are obtained

  13. Reduced γ–γ time walk to below 50 ps using the multiplexed-start and multiplexed-stop fast-timing technique with LaBr_3(Ce) detectors

    International Nuclear Information System (INIS)

    Régis, J.-M.; Saed-Samii, N.; Rudigier, M.; Ansari, S.; Dannhoff, M.; Esmaylzadeh, A.; Fransen, C.; Gerst, R.-B.; Jolie, J.; Karayonchev, V.; Müller-Gatermann, C.; Stegemann, S.

    2016-01-01

    The electronic γ–γ fast-timing technique using arrays consisting of many LaBr_3(Ce) detectors is a powerful method to determine lifetimes of nuclear excited states with a lower limit of about 5 ps. This method requires the determination of the energy-dependent time walk of the zero time which is represented by the centroid of a prompt γ–γ time distribution. The full-energy peak versus full-energy peak prompt response difference which represents the linearly combined mean γ–γ time walk of a fast-timing array consisting of 8 LaBr_3(Ce) detectors was measured using a standard "1"5"2Eu γ-ray source for the energy region of 40–1408 keV. The data were acquired using a “multiplexed-start and multiplexed-stop” analogue electronics circuitry and analysed by employing the generalized centroid difference method. Concerning the cylindrical 1.5 in.×1.5 in. LaBr_3(Ce) crystals which are coupled to the Hamamatsu R9779 photomultiplier tubes, the best fast-timing array time resolution of 202(3) ps is obtained for the two prompt γ lines of "6"0Co by using the leading-edge timing principle. When using the zero-crossover timing principle the time resolution is degraded by up to 30%, dependent on the energy and the shaping delay time of the constant fraction discriminator model Ortec 935. The smallest γ–γ time walk to below 50 ps is obtained by using a shaping delay time of about 17 ns and an optimum “time-walk adjustment” needed for detector output pulses with amplitudes smaller than 400 mV.

  14. Frequency-domain waveform inversion using the phase derivative

    KAUST Repository

    Choi, Yun Seok

    2013-09-26

    Phase wrapping in the frequency domain or cycle skipping in the time domain is the major cause of the local minima problem in the waveform inversion when the starting model is far from the true model. Since the phase derivative does not suffer from the wrapping effect, its inversion has the potential of providing a robust and reliable inversion result. We propose a new waveform inversion algorithm using the phase derivative in the frequency domain along with the exponential damping term to attenuate reflections. We estimate the phase derivative, or what we refer to as the instantaneous traveltime, by taking the derivative of the Fourier-transformed wavefield with respect to the angular frequency, dividing it by the wavefield itself and taking the imaginary part. The objective function is constructed using the phase derivative and the gradient of the objective function is computed using the back-propagation algorithm. Numerical examples show that our inversion algorithm with a strong damping generates a tomographic result even for a high ‘single’ frequency, which can be a good initial model for full waveform inversion and migration.

  15. Getting started with HTML5 WebSocket programming

    CERN Document Server

    Pterneas, Vangos

    2013-01-01

    Getting Started with HTML5 Websocket Programming takes a tutorial-based approach.This book is for anyone who wants to build high-performance, true, real-time web applications. Being familiar with frontend web development (HTML / XHTML, JavaScript) would be ideal.

  16. Starting-up sequence of the AWEC-60 wind turbine

    International Nuclear Information System (INIS)

    Avia, F.; Cruz, M. de la.

    1991-01-01

    One of the most critical status of the wind turbines operation is the starting-up sequence and the connection to the grid, due to the actuating loads that could be several times the loads during operation at rated conditions. Due to this fact, the control strategy is very important during the starting-up sequence in order to minimize the loads on the machine. For this purpose it is necessary to analyze the behaviour of the wind turbine during that sequence in different wind conditions and machine conditions. This report shows the graphic information about fifty starting-up sequences of the AWEC-60 wind turbine of 60 m. diameter and 1200 kW of rated power, recorded in April 1991 and cut-out wind speed. (author)

  17. Synchronizing Education to Adolescent Biology: "Let Teens Sleep, Start School Later"

    Science.gov (United States)

    Kelley, Paul; Lockley, Steven W.; Foster, Russell G.; Kelley, Jonathan

    2015-01-01

    Arne Duncan, US Secretary of State for Education, tweeted in 2013: "let teens sleep, start school later". This paper examines early starts and their negative consequences in the light of key research in the last 30 years in sleep medicine and circadian neuroscience. An overview of the circadian timing system in adolescence leading to…

  18. Peer Effects on Head Start Children’s Preschool Competency

    Science.gov (United States)

    DeLay, Dawn; Hanish, Laura D.; Martin, Carol Lynn; Fabes, Richard A.

    2015-01-01

    The goals of the present study were to investigate whether young children attending Head Start (N=292; Mage=4.3 years) selected peers based on their preschool competency and whether children’s levels of preschool competency were influenced by their peers’ levels of preschool competency. Children’s peer interaction partners were intensively observed several times a week over one academic year. Social network analyses revealed that children selected peer interaction partners with similar levels of preschool competency and were influenced over time by their partners’ levels of preschool competency. These effects held even after controlling for several child (e.g., sex and language) and family factors (e.g., financial strain and parent education). Implications for promoting preschool competency among Head Start children are discussed. PMID:26479545

  19. Characterisation of two-phase horizontal flow regime transition by the application of time-frequency analysis methods

    International Nuclear Information System (INIS)

    Seleghim, Paulo

    1996-01-01

    This work concerns the development of a methodology which objective is to characterize and diagnose two-phase flow regime transitions. The approach is based on the fundamental assumption that a transition flow is less stationary than a flow with an established regime. In a first time, the efforts focused on: 1) the design and construction of an experimental loop, allowing to reproduce the main horizontal two-phase flow patterns, in a stable and controlled way, 2) the design and construction of an electrical impedance probe, providing an imaged information of the spatial phase distribution in the pipe, the systematic study of the joint time-frequency and time-scale analysis methods, which permitted to define an adequate parameter quantifying the un-stationary degree. In a second time, in order to verify the fundamental assumption, a series of experiments were conducted, which objective was to demonstrate the correlation between un-stationary and regime transition. The un-stationary degree was quantified by calculating the Gabor's transform time-frequency covariance of the impedance probe signals. Furthermore, the phenomenology of each transition was characterized by the joint moments and entropy. The results clearly show that the regime transitions are correlated with local-time frequency covariance peaks, which demonstrates that these regime transitions are characterized by a loss of stationarity. Consequently, the time-frequency covariance constitutes an objective two-phase flow regime transition indicator. (author) [fr

  20. Gendered career considerations consolidate from the start of medical education.

    Science.gov (United States)

    Alers, Margret; Verdonk, Petra; Bor, Hans; Hamberg, Katarina; Lagro-Janssen, Antoine

    2014-09-13

    To explore changes in specialty preferences and work-related topics during the theoretical phase of Dutch medical education and the role of gender. A cohort of medical students at Radboudumc, the Netherlands, was surveyed at start (N=612, 69.1% female) and after three years (N=519, 69.2% female), on specialty preferences, full-time or part-time work, motivational factors, and work-life issues. Chi square tests were performed to analyze gender-differences, and logistic regression to explore the influence of gender on considerations. A total of 214 female and 78 male students completed both surveys. After three years, the male students remained highly interested in surgery, but the female students increasingly preferred gynecology. These initial preferences were predictive. Four out of five male students versus three out of five female students continued to show a full-time preference. Women increasingly preferred part-time work. After three years, the combination of work, care, and patient contact motivated female students more, whereas salary remained more important to male students. Female students indicated that their future careers would influence their family life; male students assumed having a family would only affect their partners' careers. Against an international background of the feminization of medicine, our study shows that career considerations are reinforced early in medical studies. Women prefer to work fewer hours and anticipate care tasks more often. Students' preferences reflect Dutch cultural norms about working men and women. Therefore, guidance in choice-making much earlier in medical education can create opportunities.

  1. Preliminary study in development of glass-ceramic based on SiO2-LiO2 system, starting of different SiO2 starting powders

    International Nuclear Information System (INIS)

    Daguano, J.K.M.F.; Santos, F.A.; Santos, C.; Marton, L.F.M.; Conte, R.A.; Rodrigues Junior, D.; Melo, F.C.L.

    2009-01-01

    In this work, lithium disilicate glass-ceramics were developed starting of the rice ash- SiO 2 and Li 2 CO 3 powders. The results were compared with glass ceramics based on the lithium disilicate obtained by commercial SiO 2 powders. Glass were melted at 1580 deg C, and annealed at 850 deg C. X-Ray diffraction and scanning electron microscopy were used for characterization of the materials, and hardness and fracture toughness were evaluated using Vickers indentation method. Glasses with amorphous structure were obtained in both materials. After annealing, 'rice-ash' samples presented Li 2 SiO 3 and residual SiO 2 as crystalline phases. On the other side, commercial SiO 2 - Samples presented only Li 2 Si 2 O 5 as crystalline phases and the better results of hardness and fracture toughness. (author)

  2. Study of plasma start-up initiated by second harmonic electron cyclotron resonance heating on WEGA experiment

    International Nuclear Information System (INIS)

    Preynas, M.; Laqua, H. P.; Otte, M.; Stange, T.; Aßmus, D.; Wauters, T.

    2014-01-01

    Although both 1st harmonic ordinary mode (O1) and 2nd harmonic extra-ordinary mode (X2) have been successfully used to initiate pre-ionization and breakdown in many devices, a complete theoretical model is still missing to explain the success of this method. Moreover, some experimental observations are not completely understood, such as what occurs during the delay time between the turn-on of ECRH power and first signals of density or light measurements. Since during this free period the ECRH power has to be absorbed by in-vessel components, it is of prime importance to know what governs this delay time. Recently, dedicated start-up experiments have been performed on WEGA, using a 28 GHz ECRH system in X2-mode. This machine has the interesting capability to be run also as a tokamak allowing comparative experiments between stellarator (ι/2π > 0) and tokamak (ι/2π = 0) configurations. Different scans in heating power, neutral gas pressure, and rotational transform (ι) show clearly that the start-up is a two step process. A first step following the turn-on of the ECRH power during which no measurable electron density (or just above the noise level in some cases), ECE and radiated power is detected. Its duration depends strongly on the level of injected power. The second step corresponds to the gas ionization and plasma expansion phase, with a velocity of density build-up and filling-up of the vessel volume depending mainly on pressure, gas and rotational transform. Moreover, an interesting scenario of ECRH pre-ionization without loop voltage in tokamak configuration by applying a small optimal vertical field is relevant for start-up assistance on future experiments like ITER. The results from this experimental parametric study are useful for the modeling of the start-up assisted by the second harmonic electron cyclotron resonance heating. The aim of this work is to establish predictive scenarios for both ITER and W7-X operation

  3. Study of plasma start-up initiated by second harmonic electron cyclotron resonance heating on WEGA experiment

    Energy Technology Data Exchange (ETDEWEB)

    Preynas, M.; Laqua, H. P.; Otte, M.; Stange, T.; Aßmus, D. [Max Planck Institut für Plasmaphysik, EURATOM Association, D-17491 Greifswald (Germany); Wauters, T. [Association Euratom-Belgian State, LPP-ERM/KMS, 1000 Brussels (Belgium)

    2014-02-12

    Although both 1st harmonic ordinary mode (O1) and 2nd harmonic extra-ordinary mode (X2) have been successfully used to initiate pre-ionization and breakdown in many devices, a complete theoretical model is still missing to explain the success of this method. Moreover, some experimental observations are not completely understood, such as what occurs during the delay time between the turn-on of ECRH power and first signals of density or light measurements. Since during this free period the ECRH power has to be absorbed by in-vessel components, it is of prime importance to know what governs this delay time. Recently, dedicated start-up experiments have been performed on WEGA, using a 28 GHz ECRH system in X2-mode. This machine has the interesting capability to be run also as a tokamak allowing comparative experiments between stellarator (ι/2π > 0) and tokamak (ι/2π = 0) configurations. Different scans in heating power, neutral gas pressure, and rotational transform (ι) show clearly that the start-up is a two step process. A first step following the turn-on of the ECRH power during which no measurable electron density (or just above the noise level in some cases), ECE and radiated power is detected. Its duration depends strongly on the level of injected power. The second step corresponds to the gas ionization and plasma expansion phase, with a velocity of density build-up and filling-up of the vessel volume depending mainly on pressure, gas and rotational transform. Moreover, an interesting scenario of ECRH pre-ionization without loop voltage in tokamak configuration by applying a small optimal vertical field is relevant for start-up assistance on future experiments like ITER. The results from this experimental parametric study are useful for the modeling of the start-up assisted by the second harmonic electron cyclotron resonance heating. The aim of this work is to establish predictive scenarios for both ITER and W7-X operation.

  4. An adaptive time-stepping strategy for solving the phase field crystal model

    International Nuclear Information System (INIS)

    Zhang, Zhengru; Ma, Yuan; Qiao, Zhonghua

    2013-01-01

    In this work, we will propose an adaptive time step method for simulating the dynamics of the phase field crystal (PFC) model. The numerical simulation of the PFC model needs long time to reach steady state, and then large time-stepping method is necessary. Unconditionally energy stable schemes are used to solve the PFC model. The time steps are adaptively determined based on the time derivative of the corresponding energy. It is found that the use of the proposed time step adaptivity cannot only resolve the steady state solution, but also the dynamical development of the solution efficiently and accurately. The numerical experiments demonstrate that the CPU time is significantly saved for long time simulations

  5. Berry phase for spin-1/2 particles moving in a space-time with torsion

    International Nuclear Information System (INIS)

    Alimohammadi, M.; Shariati, A.

    2001-01-01

    Berry phase for a spin-1/2 particle moving in a flat space-time with torsion is investigated in the context of the Einstein-Cartan-Dirac model. It is shown that if the torsion is due to a dense polarized background, then there is a Berry phase only if the fermion is massless and its momentum is perpendicular to the direction of the background polarization. The order of magnitude of this Berry phase is discussed in other theoretical frameworks. (orig.)

  6. Berry phase for spin-1/2 particles moving in a space-time with torsion

    Energy Technology Data Exchange (ETDEWEB)

    Alimohammadi, M. [Dept. of Physics, Tehran Univ. (Iran); Shariati, A. [Inst. for Advanced Studies in Basic Sciences, Zanjan (Iran); Inst. for Studies in Theoretical Physics and Mathematics, Tehran (Iran)

    2001-06-01

    Berry phase for a spin-1/2 particle moving in a flat space-time with torsion is investigated in the context of the Einstein-Cartan-Dirac model. It is shown that if the torsion is due to a dense polarized background, then there is a Berry phase only if the fermion is massless and its momentum is perpendicular to the direction of the background polarization. The order of magnitude of this Berry phase is discussed in other theoretical frameworks. (orig.)

  7. Start-up test of Fukushima Daini Nuclear Power Station Unit No.3

    International Nuclear Information System (INIS)

    Inomata, Toshio; Umezu, Akira; Kajikawa, Makoto; Koibuchi, Hiroshi; Netsu, Nobuhiko.

    1986-01-01

    In Unit 3 of the Fukushima Nuclear Power Station II (daini), a BWR power plant of output 1,100 MW, commercial operation was started in June 1985. Its start-up test was finished successfully in about nine months. That is, new equipments introduced were demonstration tested. Though the items of testing are increased, the start-up test took short time, resulting in construction period only 54.7 months of the Unit 3, the shortest in the world. During the test, there was no scramming other than the planned. Described are the following: an outline of the Unit 3, the items of its improvement and standardization, including the new equipments, preparations for the start-up test, the start-up test and its evaluation. (Mori, K.)

  8. Nanoindentation study of ferrite–martensite dual phase steels developed by a new thermomechanical processing

    Energy Technology Data Exchange (ETDEWEB)

    Mazaheri, Yousef, E-mail: y.mazaheri@ma.iut.ac.ir [Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of); Faculty of Engineering, Bu-Ali Sina University, Hamedan 65178-38695 (Iran, Islamic Republic of); Kermanpur, Ahmad; Najafizadeh, Abbas [Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of)

    2015-07-15

    Dual phase (DP) steels consisting different volume fractions of ferrite and martensite and different ferrite grain size were produced by a new route utilizing cold-rolling and subsequent intercritical annealing of ferrite/martensite duplex starting structure at 770 °C for different times. Scanning electron microscopy has been supplemented by nanoindentation and tensile test to follow microstructural changes and their correlations to the variation in phase's hardness and mechanical properties. The results showed that longer holding times resulted in coarser and softer ferrite grains in DP microstructures. Martensite nanohardness variation with holding time is related to change in its carbon content. Mechanical properties such as strength, elongation and toughness are well correlated with the martensite/ferrite hardness ratio.

  9. Analysis of the start-up and control of a particle bed reactor

    International Nuclear Information System (INIS)

    Lazareth, O.W.; Araj, K.J.; Horn, F.L.; Ludewig, H.; Powell, J.R.

    1987-01-01

    This study describes the modeling of start-up transients in Particle Bed Reactors (PBR) for burst electric power. Two computer programs have been developed to analyze the start-up process. The first program (named KINETIC) analyzes the entire fuel element, calculating time dependent solutions for power and the temperature distribution in the packed bed. The second program (named SPHEAT, for Spherical Heating) calculates time-dependent temperatures inside individual, cladded fuel particles. The two programs provide powerful analytical tools for evaluation of material and geometrical options, power and time constraints, and conditions that could lead to element failures

  10. Starting an aphasia center?

    Science.gov (United States)

    Elman, Roberta J

    2011-08-01

    Starting an aphasia center can be an enormous challenge. This article provides initial issues to review and consider when deciding whether starting a new organization is right for you. Determining the need for the program in your community, the best size and possible affiliation for the organization, and available resources, as well as developing a business plan, marketing the program, and building awareness in the community, are some of the factors that are discussed. Specific examples related to starting the Aphasia Center of California are provided. © Thieme Medical Publishers.

  11. Time-dependent angular distribution of sputtered particles from amorphous targets

    International Nuclear Information System (INIS)

    Yamamura, Yasunori

    1990-01-01

    Using the time-evolution computer simulation code DYACAT, the time-dependent behavior of sputtering phenomena has been investigated. The DYACAT program is based on the binary collision approximation, and the cascade development in solids is followed time-evolutionally. The total sputtering yield, the angular distribution and the energy distribution of sputtered atoms are calculated as a function of time for 1 keV Ar→Cu, where the angle of incidence is the inverse surface normal. It is found that the angular distribution of the prompt collisional phase of the sputtering process shows an under-cosine and that the corresponding energy spectrum has a peak near 10 eV. The slow collisional phase of 1 keV Ar→Cu will start after 3x10 -14 s, and its angular distribution shows an over-cosine distribution. (orig.)

  12. Measuring Gait Quality in Parkinson’s Disease through Real-Time Gait Phase Recognition

    Directory of Open Access Journals (Sweden)

    Ilaria Mileti

    2018-03-01

    Full Text Available Monitoring gait quality in daily activities through wearable sensors has the potential to improve medical assessment in Parkinson’s Disease (PD. In this study, four gait partitioning methods, two based on thresholds and two based on a machine learning approach, considering the four-phase model, were compared. The methods were tested on 26 PD patients, both in OFF and ON levodopa conditions, and 11 healthy subjects, during walking tasks. All subjects were equipped with inertial sensors placed on feet. Force resistive sensors were used to assess reference time sequence of gait phases. Goodness Index (G was evaluated to assess accuracy in gait phases estimation. A novel synthetic index called Gait Phase Quality Index (GPQI was proposed for gait quality assessment. Results revealed optimum performance (G < 0.25 for three tested methods and good performance (0.25 < G < 0.70 for one threshold method. The GPQI resulted significantly higher in PD patients than in healthy subjects, showing a moderate correlation with clinical scales score. Furthermore, in patients with severe gait impairment, GPQI was found higher in OFF than in ON state. Our results unveil the possibility of monitoring gait quality in PD through real-time gait partitioning based on wearable sensors.

  13. OPTIMAL CONTROL OF AUTOCLAVE START MODE IN THE PRODUCTION OF NITRIC ACID

    OpenAIRE

    Ладієва, Леся Ростиславівна; Ширма, А. В.

    2015-01-01

    The algorithm of optimal control of autoclave start mode in the production of nitric acid is proposed. By optimality criterion is selected minimum time-autoclave at preset mode with the restriction on the concentration of nitric acid. End time start mode is entered on the terminal part of the cost function. The method of penalties and a gradient procedure is used to solve the problem. The applied algorithm is allowed to bring an autoclave at a given technological regime.Keywords: production o...

  14. Directional spectrum of ocean waves from array measurements using phase/time/path difference methods

    Digital Repository Service at National Institute of Oceanography (India)

    Fernandes, A.A.; Sarma, Y.V.B.; Menon, H.B.

    Wave direction has for the first time been consistently, accurately and unambiguously evaluated from array measurements using the phase/time/path difference (PTPD) methods of Esteva in case of polygonal arrays and Borgman in case of linear arrays...

  15. Study of the timing performance of the SKIROC2-CMS for the CMS HGCAL

    CERN Document Server

    Huiberts, Simon Kristian

    2017-01-01

    The High Luminosity phase of the LHC (starting operation in 2025) will provide unprecedented instantaneous and integrated luminosity, with 25 ns bunch crossing intervals and up to 140 pileup events. In this context, the High Granularity Calorimeter will provide electromagnetic and hadronic energy measurement in the forward direction of the upgraded CMS. The test beam campaign of the first HGCal modules, started in Summer 2016 at CERN with 8 fully equipped layers of the EE section, will continue in Summer 2017 aiming at the test of a full prototype including the electronic and the hadronic parts. The assessment of the calorimeter performance on a beam test bench is a fundamental phase for the development of a new detector, allowing to test the mechanical structure and electronic chain, characterize the modules performance and measure the shower developments for electrons and hadrons. The aim of the work was to determine the timing performance and the timing characteristics of the single module tested in May 2...

  16. Cardiovascular and noncardiovascular mortality among patients starting dialysis

    DEFF Research Database (Denmark)

    de Jager, Dinanda J; Grootendorst, Diana C; Jager, Kitty J

    2009-01-01

    CONTEXT: Cardiovascular mortality is considered the main cause of death in patients receiving dialysis and is 10 to 20 times higher in such patients than in the general population. OBJECTIVE: To evaluate if high overall mortality in patients starting dialysis is a consequence of increased cardiov...

  17. A Compact Safe Cold-Start (CS2) System for Scramjets using Dilute Triethylaluminum Fuel Mixtures, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal addresses the cold-start requirements of scramjet engines by developing a safe, energy-dense, and low volume hydrocarbon fuel conditioning system based...

  18. Looking for What's Next: Is It Time to Start Talking about Library 2.1?

    Science.gov (United States)

    Mathews, Brian S.

    2009-01-01

    For a while, the idea of social software was something that had to be sold. Although many librarians were experimenting with it, there were a lot of concerns. Now, social software, like Library 2.1, is starting to be viewed less as a disruptive force and more as a regular part of a librarian's workflow. This article highlights a few examples that…

  19. Reduced γ–γ time walk to below 50 ps using the multiplexed-start and multiplexed-stop fast-timing technique with LaBr{sub 3}(Ce) detectors

    Energy Technology Data Exchange (ETDEWEB)

    Régis, J.-M., E-mail: regis@ikp.uni-koeln.de [Institut für Kernphysik der Universität zu Köln, Zülpicher Str. 77, 50937 Köln (Germany); Saed-Samii, N., E-mail: nima@ikp.uni-koeln.de [Institut für Kernphysik der Universität zu Köln, Zülpicher Str. 77, 50937 Köln (Germany); Rudigier, M. [Institut für Kernphysik der Universität zu Köln, Zülpicher Str. 77, 50937 Köln (Germany); Department of Physics, University of Surrey, Guildford GU2 7XH (United Kingdom); Ansari, S.; Dannhoff, M.; Esmaylzadeh, A.; Fransen, C.; Gerst, R.-B.; Jolie, J.; Karayonchev, V.; Müller-Gatermann, C.; Stegemann, S. [Institut für Kernphysik der Universität zu Köln, Zülpicher Str. 77, 50937 Köln (Germany)

    2016-07-01

    The electronic γ–γ fast-timing technique using arrays consisting of many LaBr{sub 3}(Ce) detectors is a powerful method to determine lifetimes of nuclear excited states with a lower limit of about 5 ps. This method requires the determination of the energy-dependent time walk of the zero time which is represented by the centroid of a prompt γ–γ time distribution. The full-energy peak versus full-energy peak prompt response difference which represents the linearly combined mean γ–γ time walk of a fast-timing array consisting of 8 LaBr{sub 3}(Ce) detectors was measured using a standard {sup 152}Eu γ-ray source for the energy region of 40–1408 keV. The data were acquired using a “multiplexed-start and multiplexed-stop” analogue electronics circuitry and analysed by employing the generalized centroid difference method. Concerning the cylindrical 1.5 in.×1.5 in. LaBr{sub 3}(Ce) crystals which are coupled to the Hamamatsu R9779 photomultiplier tubes, the best fast-timing array time resolution of 202(3) ps is obtained for the two prompt γ lines of {sup 60}Co by using the leading-edge timing principle. When using the zero-crossover timing principle the time resolution is degraded by up to 30%, dependent on the energy and the shaping delay time of the constant fraction discriminator model Ortec 935. The smallest γ–γ time walk to below 50 ps is obtained by using a shaping delay time of about 17 ns and an optimum “time-walk adjustment” needed for detector output pulses with amplitudes smaller than 400 mV.

  20. Electron spin echo studies of the internal motion of radicals in crystals: Phase memory vs correlation time

    International Nuclear Information System (INIS)

    Kispert, L.D.; Bowman, M.K.; Norris, J.R.; Brown, M.S.

    1982-01-01

    An electron spin echo (ESE) study of the internal motion of the CH 2 protons in irradiated zinc acetate dihydrate crystals shows that quantitative measurements of the motional correlation time can be obtained quite directly from pulsed measurements. In the slow motional limit, the motional correlation time is equal to the phase memory time determined by ESE. In the fast motional limit, the motional correlation time is proportional to the no motion spectral second moment divided by the ESE phase memory time. ESE offers a convenient method of studying motion, electron transfer, conductivity, etc. in a variety of systems too complicated for study by ordinary EPR. New systems for study by ESE include biological samples, organic polymers, liquid solutions of radicals with unresolved hyperfine, etc. When motion modulates large anisotropic hyperfine couplings, ESE measurements of the phase memory time are sensitive to modulation of pseudosecular hyperfine interactions

  1. Polynomial Phase Estimation Based on Adaptive Short-Time Fourier Transform.

    Science.gov (United States)

    Jing, Fulong; Zhang, Chunjie; Si, Weijian; Wang, Yu; Jiao, Shuhong

    2018-02-13

    Polynomial phase signals (PPSs) have numerous applications in many fields including radar, sonar, geophysics, and radio communication systems. Therefore, estimation of PPS coefficients is very important. In this paper, a novel approach for PPS parameters estimation based on adaptive short-time Fourier transform (ASTFT), called the PPS-ASTFT estimator, is proposed. Using the PPS-ASTFT estimator, both one-dimensional and multi-dimensional searches and error propagation problems, which widely exist in PPSs field, are avoided. In the proposed algorithm, the instantaneous frequency (IF) is estimated by S-transform (ST), which can preserve information on signal phase and provide a variable resolution similar to the wavelet transform (WT). The width of the ASTFT analysis window is equal to the local stationary length, which is measured by the instantaneous frequency gradient (IFG). The IFG is calculated by the principal component analysis (PCA), which is robust to the noise. Moreover, to improve estimation accuracy, a refinement strategy is presented to estimate signal parameters. Since the PPS-ASTFT avoids parameter search, the proposed algorithm can be computed in a reasonable amount of time. The estimation performance, computational cost, and implementation of the PPS-ASTFT are also analyzed. The conducted numerical simulations support our theoretical results and demonstrate an excellent statistical performance of the proposed algorithm.

  2. Real-time generation of the Wigner distribution of complex functions using phase conjugation in photorefractive materials.

    Science.gov (United States)

    Sun, P C; Fainman, Y

    1990-09-01

    An optical processor for real-time generation of the Wigner distribution of complex amplitude functions is introduced. The phase conjugation of the input signal is accomplished by a highly efficient self-pumped phase conjugator based on a 45 degrees -cut barium titanate photorefractive crystal. Experimental results on the real-time generation of Wigner distribution slices for complex amplitude two-dimensional optical functions are presented and discussed.

  3. Cryptographic robustness of a quantum cryptography system using phase-time coding

    International Nuclear Information System (INIS)

    Molotkov, S. N.

    2008-01-01

    A cryptographic analysis is presented of a new quantum key distribution protocol using phase-time coding. An upper bound is obtained for the error rate that guarantees secure key distribution. It is shown that the maximum tolerable error rate for this protocol depends on the counting rate in the control time slot. When no counts are detected in the control time slot, the protocol guarantees secure key distribution if the bit error rate in the sifted key does not exceed 50%. This protocol partially discriminates between errors due to system defects (e.g., imbalance of a fiber-optic interferometer) and eavesdropping. In the absence of eavesdropping, the counts detected in the control time slot are not caused by interferometer imbalance, which reduces the requirements for interferometer stability.

  4. 30 CFR 75.1913 - Starting aids.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Starting aids. 75.1913 Section 75.1913 Mineral... SAFETY STANDARDS-UNDERGROUND COAL MINES Diesel-Powered Equipment § 75.1913 Starting aids. (a) Volatile fuel starting aids shall be used in accordance with recommendations provided by the starting aid...

  5. Optimal Rotor Design of Line Start Permanent Magnet Synchronous Motor by Genetic Algorithm

    Directory of Open Access Journals (Sweden)

    Bui Minh Dinh

    2017-07-01

    Full Text Available Line start permanent magnet synchronous motor (LSPMSM is one of the highest efficiency motors due to no rotor copper loss at synchronous speed and self-starting. LSPMSM has torque characteristics of both induction motor IM and Permanent Magnet Synchronous Motor-PMSM. Using Genetic Algorithm (GA for balancing magnetic cost and for copper loss minimization, the magnetic sizes and geometry parameter of stator and rotor are found and manufactured for industrial evaluation. This article is also taking account practical manufacturing factors to minimize mass production cost. In order to maximize efficiency, an optimal design method of cage-bars and magnet shape has to be considered. The geometry parameters of stator and rotor can be obtained by an analytical model method and validated by FEM simulation. This paper presents the optimal rotor design of a three-phase line-start permanent magnet motor (LSPM considering the starting torque and efficiency. To consider nonlinear characteristics, the design process is comprised of the FEM and analytical method. During this study, permanent-magnets and cage bars were designed using the magnetic equivalent circuit method and the barriers that control all magnetic flux were designed using the FEM, and the tradeoff of starting torque and efficiency is controlled by weight function in Taguchi method simulation. Finally, some practical results have been obtained and analyzed based on a LSPMSM test bench.

  6. Coherent control of interfering wave packets in dissociating HD+ molecules: the role of phase and delay time

    International Nuclear Information System (INIS)

    Qin, Chaochao; Zhang, Lili; Zhang, Xianzhou; Liu, Yufang; Qiu, Xuejun

    2016-01-01

    The coherent control of interference between dissociating wave packets of the HD + molecules generated by a pair of time-delayed and phase-locked femtosecond laser pulses is theoretically studied by using the time-dependent quantum wave packet method. The density function in both coordinate and momentum representation are presented and discussed. It is demonstrated that the interference pattern is observed in both coordinate and momentum density functions. The interference undergoes a π-phase shift when the delay time between the two phase-locked femtosecond laser pulses is changed by half an optical period. In particular, the number of interference fringes, the fringe spacing in the R-dependent density distribution |ψ(R)| 2 , and the modulation period of the energy-dependent distribution of the fragments P(E) can be tuned by two phase-locked femtosecond pulses. (paper)

  7. Variable School Start Times and Middle School Student's Sleep Health and Academic Performance.

    Science.gov (United States)

    Lewin, Daniel S; Wang, Guanghai; Chen, Yao I; Skora, Elizabeth; Hoehn, Jessica; Baylor, Allison; Wang, Jichuan

    2017-08-01

    Improving sleep health among adolescents is a national health priority and implementing healthy school start times (SSTs) is an important strategy to achieve these goals. This study leveraged the differences in middle school SST in a large district to evaluate associations between SST, sleep health, and academic performance. This cross-sectional study draws data from a county-wide surveillance survey. Participants were three cohorts of eighth graders (n = 26,440). The school district is unique because SST ranged from 7:20 a.m. to 8:10 a.m. Path analysis and probit regression were used to analyze associations between SST and self-report measures of weekday sleep duration, grades, and homework controlling for demographic variables (sex, race, and socioeconomic status). The independent contributions of SST and sleep duration to academic performance were also analyzed. Earlier SST was associated with decreased sleep duration (χ 2  = 173, p academic performance, and academic effort. Path analysis models demonstrated the independent contributions of sleep duration, SST, and variable effects for demographic variables. This is the first study to evaluate the independent contributions of SST and sleep to academic performance in a large sample of middle school students. Deficient sleep was prevalent, and the earliest SST was associated with decrements in sleep and academics. These findings support the prioritization of policy initiatives to implement healthy SST for younger adolescents and highlight the importance of sleep health education disparities among race and gender groups. Copyright © 2017 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

  8. Jump Starting Entrepreneurship

    DEFF Research Database (Denmark)

    Burcharth, Ana; Smith, Pernille; Frederiksen, Lars

    How do laid-off employees become entrepreneurs after receiving a dream start into self-employment? This question is relevant for policy makers and entrepreneurship researchers alike since it raises the possibility of a reverse entrepreneurial opportunity, in which the chance of becoming an entrep......How do laid-off employees become entrepreneurs after receiving a dream start into self-employment? This question is relevant for policy makers and entrepreneurship researchers alike since it raises the possibility of a reverse entrepreneurial opportunity, in which the chance of becoming...... an entrepreneur emerges before the discovery of a profitable opportunity. We empirically examine this question on the unique setting of a corporate entrepreneurship program. In the midst of a corporate crisis, Nokia supported laid-off employees to start their own ventures under favorable conditions. We...... persevered in their endeavors and eventually became comfortable with their new career prospects. We discuss the psychological factors that impact career transition after organizational closure and theorize weather they encourage or discourage entrepreneurship....

  9. Fiscal Consolidation Start and its Determinants Analysis Within European Member Countries

    Directory of Open Access Journals (Sweden)

    Lucia Mihóková

    2017-09-01

    Full Text Available Purpose: The purpose of the research from the theoretical point of view is to define the "start of fiscal consolidation" and to clarify the effects of selected determinants on its initiation. The purpose of the paper, in an empirical context, is to empirically assess the impact of selected determinants on the start of consolidation in the EU member states in 1995-2015 using quantitative economics. The paper was developed within the project VEGA 1/0967/15. Methodology: The empirical assessment of the research objective is divided into four phases: (1 creation of research review using EBHC methodology, (2 identification of “start” of fiscal consolidation within selected period, (3 panel econometric analysis: model specification, quantification of model’s parameters and model verification and (4 research assessment and discussion. Within the analysis, the traditional, specific and general methods were used (systemic review according to EBHC methodology, content analysis, panel regression analysis, synthesis. Approach: Approach identifies “start” of consolidation episodes using selected identification rules. Using the panel regression analysis (OLS, FEM and REM models approach the statistically significant macroeconomic, fiscal, political and other determinants and quantification of the polarity of their impact on the fiscal consolidation start were analysed. Findings: Based on the performed econometric analysis can be stated that the start of consolidation is significantly determined by initial macroeconomic and fiscal situation in the country which are captured by the size of output gap and GDP growth as well as the size of CAPB, budget expenditure and the revenue side. Political and other determinants (such as crisis can also influence the start of consolidation episodes..

  10. Effect of lead addition on the formation of superconducting phases in Bi-Sr-Ca-Cu-O ceramics

    International Nuclear Information System (INIS)

    Martinelli, A.E.

    1991-01-01

    Superconducting ceramics with starting composition Bi 2 - x Pb x Sr 2 Ca 2 Cu 3 O y (0,0 ≤ X ≤ 0,6) were prepared in order to investigate the effects of partial substitution of Pb for Bi and sintering time and atmosphere in the formation of superconducting phases. For all samples X-ray diffraction analyses were performed to estimate the amount of superconducting phases; superconductivity was analysed by dc electrical resistance and ac magnetic susceptibility measurements. The main results show that: a) the longer the sintering time (up to 168 h), the larger the volume fraction of superconducting phases with critical temperature (T c ) greater than the temperature of nitrogen liquefaction; b) by partially substituting Pb for Bi it is possible to restrain the formation of 2212 phase (T c = 80 K) and to enhance the amount of 2223 phase (T c = 105 K); C) a heat treatment under oxygen atmosphere before sintering enhances the formation of 2223 phase. (author)

  11. Crystallization of cristobalite from glass phase in mullite ceramics with excess SiO{sub 2} compositions; Sirika kajo muraito seramikkusu chu no garasuso no kesshoka kyodo

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Takashi; Sugai, Mikio; Nakagawa, Zenbee [Akita University, Akita (Japan). Faculty of Engineering and Resource Science; Sawabe, Yoshinari [Sumitomo Chemical Corp., Ibaraki (Japan). Tsukuba Research Laboratory; Oya, Yutaka [Gifu University, Gifu (Japan). Faculty of Engineering

    1999-09-01

    Crystallization of glass phase to cristobalite was investigated in mullite-glass ceramics with excess SiO{sub 2} compositions (5.3-16.4 mass %), namely, higher than stoichiometric mullite. Starting powders were prepared by alkoxide hydrolysis method. Compact specimens were sintered at 1600 degree C above the eutectic temperature (1587 degree C) for 2 h. Crystallization treatment was carried out at 1500 degree C, below the eutectic temperature, for times from 4 h to 96 h. Crystallization of glass phase proceeded from the surface of the specimen toward its inner part, in linear dependence on the annealing time. At the polished surface of the specimen, crystallization started in large glass pockets and the crystallized area extended spherically toward the inner part. This phenomenon suggests that nucleation occurs at the minimum parts in the elastic energy generated by the volume change involved in the crystallization of glass phase to cristobalite. (author)

  12. Influence of starting powder milling on magnetic properties of Mn-Zn ferrite

    Directory of Open Access Journals (Sweden)

    Miodrag M. Milutinov

    2017-06-01

    Full Text Available In this paper, the influence of additional sieving and milling of starting industrial Mn-Zn powders on magnetic properties was investigated. The starting powder was milled for 60 minutes, followed by sieving through 325 and 400 meshes. The starting and milled powders were used to fabricate toroid shaped samples sintered at 1200°C for 2 hours. Structural parameters of the fabricated samples were analysed by X-ray diffraction and scanning electron microscopy. Complex permeability, core loss density, and hysteresis were measured using the modified watt-meter method. The complex permeability and hysteresis loop were modelled with a new model proposed in the paper. The core loss density was modelled with the Steinmetz empirical equation. The experimental results and calculations show the significance of the additional milling and sieving process on magnetic properties of Mn-Zn ferrite in the frequency range 0.1-10MHz. These processes increase the relative permeability about 3 times and decrease the core loss 4 times by milling of the starting powder.

  13. Phased Startup Initiative Phases 3 and 4 Test Plan and Test Specification (OCRWM)

    International Nuclear Information System (INIS)

    PITNER, A.L.

    2000-01-01

    Construction for the Spent Nuclear Fuel (SNF) Project facilities is continuing per the Level III Baseline Schedule, and installation of the Fuel Retrieval System (FRS) and Integrated Water Treatment System (IWTS) in K West Basin is now complete. In order to accelerate the project, a phased start up strategy to initiate testing of the FRS and IWTS early in the overall project schedule was proposed (Williams 1999). Wilkinson (1999) expands the definition of the original proposal into four functional testing phases of the Phased Startup Initiative (PSI). Phases 1 and 2 are based on performing functional tests using dummy fuel. These tests are described in separate planning documents. This test plan provides overall guidance for Phase 3 and 4 tests, which are performed using actual irradiated N fuel assemblies. The overall objective of the Phase 3 and 4 testing is to verify how the FRS and IWTS respond while processing actual fuel. Conducting these tests early in the project schedule will allow identification and resolution of equipment and process problems before they become activities on the start-up critical path. The specific objectives of this test plan are to: (1) Define the test scope for the FRS and IWTS; (2) Provide detailed test requirements that can be used to write the specific test procedures; (3) Define data required and measurements to be taken. Where existing methods to obtain these do not exist, enough detail will be provided to define required additional equipment; and (4) Define specific test objectives and acceptance criteria

  14. Systemic Inflammation, Coagulation, and Clinical Risk in the START Trial

    DEFF Research Database (Denmark)

    Baker, Jason V; Sharma, Shweta; Grund, Birgit

    2017-01-01

    Background: The Strategic Timing of AntiRetroviral Treatment (START) trial demonstrated that immediate (at CD4+ >500 cells/µL) vs deferred (to CD4+ ... available for 4299 START participants (92%). Mean follow-up was 3.2 years. Higher levels of IL-6 and D-dimer were the only biomarkers associated with risk for AIDS, SNA or death, as well as the individual components of SNA and AIDS events (HRs ranged 1.37-1.41 per 2-fold higher level), even after adjustment...

  15. Industrialization of Polymer Solar Cells – phase 1

    DEFF Research Database (Denmark)

    Lauritzen, Hanne; Bork, Jakob; Andersen, Rasmus B.

    into more refined products. Such refined products might be self-powered electronic devices designed for easy integration in the customer’s production or solar-powered products for the end-user. A three-phased project with the objective to industrialize DTU’s basic polymer solar cell technology was started...... in the summer of 2009. The technology comprises a specific design of the polymer solar cell and a corresponding roll-to-roll manufacturing process. This basic technology is referred to as ProcessOne in the open literature. The present report relates to the project’s phase 1.The key tasks in phase 1...... to a slot-die printing head manufactured in DTU’s workshop. The line was at the same time adjusted and updated to handle the new production. The very first solar cells produced on this line appeared in July 2010. The line has subse-quently been upgraded on a running basis, and Mekoprint’s operators have...

  16. 76 FR 50813 - Major Capital Investment Projects; Guidance on News Starts/Small Starts Policies and Procedures

    Science.gov (United States)

    2011-08-16

    ... DEPARTMENT OF TRANSPORTATION Federal Transit Administration Major Capital Investment Projects; Guidance on News Starts/Small Starts Policies and Procedures AGENCY: Federal Transit Administration (FTA... Administration (FTA) to publish policy guidance on the New and Small Starts capital project review and evaluation...

  17. A comparison of base running start techniques in collegiate fastpitch softball athletes

    OpenAIRE

    Massey, Kelly P.; Brouillette, Kelly Miller; Martino, Mike

    2018-01-01

    This study examined the time difference between three different base running start techniques. Thirteen Division II collegiate softball players performed maximal sprints off a softball bag at two different distances. Sprint times at 4.57 and 18.29 meters for each technique were measured using Fusion Sport’s Smartspeed System. At both 4.57 and 18.29 meters, the rocking start (0.84 ± 0.10; 3.04 ± 0.16 s) was found to be significantly faster (in seconds) than both the split technique (1.01 ± 0.0...

  18. Real Time Phase Noise Meter Based on a Digital Signal Processor

    Science.gov (United States)

    Angrisani, Leopoldo; D'Arco, Mauro; Greenhall, Charles A.; Schiano Lo Morille, Rosario

    2006-01-01

    A digital signal-processing meter for phase noise measurement on sinusoidal signals is dealt with. It enlists a special hardware architecture, made up of a core digital signal processor connected to a data acquisition board, and takes advantage of a quadrature demodulation-based measurement scheme, already proposed by the authors. Thanks to an efficient measurement process and an optimized implementation of its fundamental stages, the proposed meter succeeds in exploiting all hardware resources in such an effective way as to gain high performance and real-time operation. For input frequencies up to some hundreds of kilohertz, the meter is capable both of updating phase noise power spectrum while seamlessly capturing the analyzed signal into its memory, and granting as good frequency resolution as few units of hertz.

  19. 45 CFR 1308.21 - Parent participation and transition of children into Head Start and from Head Start to public...

    Science.gov (United States)

    2010-10-01

    ... into Head Start and from Head Start to public school. 1308.21 Section 1308.21 Public Welfare... AND HUMAN SERVICES THE ADMINISTRATION FOR CHILDREN, YOUTH AND FAMILIES, HEAD START PROGRAM HEAD START... Standards § 1308.21 Parent participation and transition of children into Head Start and from Head Start to...

  20. Business incubator as a support measure for start-ups in Russia and Sweden. : Comparative analysis.

    OpenAIRE

    Kiseleva, Maria

    2017-01-01

    Growth and developing of start-ups plays an important role as starting new business is one of the indicator that shows the economy level of each country. At that time start-ups need support and one of such support institutions is business incubator who can provide all resources that start-ups need. Different studies exist about business incubator as a support measure and the role of them for start- ups, but there is a lack of studies in analyzing this topic in different business environments....

  1. Device for the nuclear reactor automatic start-up and power control

    International Nuclear Information System (INIS)

    Nikiforov, B.N.; Volkov, A.V.; Ogon'kov, A.I.

    1978-01-01

    A description and flowsheet of a reactor start-up and power-control automatic device containing no nonlinear elements with a relay characteristic are presented. The device consists of two independent channels for measuring the physical power and time (period) constant of the reactor. Requirements for the device are considered, based on the condition of a minimum permissible number of a servomechanism operations due to fluctuations of an input signal which appear because of the statistical nature of processes taking place in the reactor. It is noted that the threshold amplifier used in the device allows a considerable decrease of the reactor start-up time

  2. Timing of Formal Phase Safety Reviews for Large-Scale Integrated Hazard Analysis

    Science.gov (United States)

    Massie, Michael J.; Morris, A. Terry

    2010-01-01

    Integrated hazard analysis (IHA) is a process used to identify and control unacceptable risk. As such, it does not occur in a vacuum. IHA approaches must be tailored to fit the system being analyzed. Physical, resource, organizational and temporal constraints on large-scale integrated systems impose additional direct or derived requirements on the IHA. The timing and interaction between engineering and safety organizations can provide either benefits or hindrances to the overall end product. The traditional approach for formal phase safety review timing and content, which generally works well for small- to moderate-scale systems, does not work well for very large-scale integrated systems. This paper proposes a modified approach to timing and content of formal phase safety reviews for IHA. Details of the tailoring process for IHA will describe how to avoid temporary disconnects in major milestone reviews and how to maintain a cohesive end-to-end integration story particularly for systems where the integrator inherently has little to no insight into lower level systems. The proposal has the advantage of allowing the hazard analysis development process to occur as technical data normally matures.

  3. Synthesis of pure Portland cement phases

    DEFF Research Database (Denmark)

    Wesselsky, Andreas; Jensen, Ole Mejlhede

    2009-01-01

    Pure phases commonly found in Portland cement clinkers are often used to test cement hydration behaviour in simplified experimental conditions. The synthesis of these phases is covered in this paper, starting with a description of phase relations and possible polymorphs of the four main phases...... in Portland cement, i.e. tricalcium silicate, dicalcium silicate, tricalcium aluminate and tetracalcium alumino ferrite. Details of the The process of solid state synthesis are is described in general including practical advice on equipment and techniques. Finally In addition, some exemplary mix compositions...

  4. The use of Fourier reverse transforms in crystallographic phase refinement

    Energy Technology Data Exchange (ETDEWEB)

    Ringrose, Sharon [Iowa State Univ., Ames, IA (United States)

    1997-10-08

    Often a crystallographer obtains an electron density map which shows only part of the structure. In such cases, the phasing of the trial model is poor enough that the electron density map may show peaks in some of the atomic positions, but other atomic positions are not visible. There may also be extraneous peaks present which are not due to atomic positions. A method for determination of crystal structures that have resisted solution through normal crystallographic methods has been developed. PHASER is a series of FORTRAN programs which aids in the structure solution of poorly phased electron density maps by refining the crystallographic phases. It facilitates the refinement of such poorly phased electron density maps for difficult structures which might otherwise not be solvable. The trial model, which serves as the starting point for the phase refinement, may be acquired by several routes such as direct methods or Patterson methods. Modifications are made to the reverse transform process based on several assumptions. First, the starting electron density map is modified based on the fact that physically the electron density map must be non-negative at all points. In practice a small positive cutoff is used. A reverse Fourier transform is computed based on the modified electron density map. Secondly, the authors assume that a better electron density map will result by using the observed magnitudes of the structure factors combined with the phases calculated in the reverse transform. After convergence has been reached, more atomic positions and less extraneous peaks are observed in the refined electron density map. The starting model need not be very large to achieve success with PHASER; successful phase refinement has been achieved with a starting model that consists of only 5% of the total scattering power of the full molecule. The second part of the thesis discusses three crystal structure determinations.

  5. Virtual Sensor Test Instrumentation, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Mobitrum has started the development of virtual sensor test instrumentation in Phase I for characterization and measurement of ground testing of propulsion systems....

  6. Process algebra with timing : real time and discrete time

    NARCIS (Netherlands)

    Baeten, J.C.M.; Middelburg, C.A.; Bergstra, J.A.; Ponse, A.J.; Smolka, S.A.

    2001-01-01

    We present real time and discrete time versions of ACP with absolute timing and relative timing. The starting-point is a new real time version with absolute timing, called ACPsat, featuring urgent actions and a delay operator. The discrete time versions are conservative extensions of the discrete

  7. Path to Smoking Addiction Starts at Very Young Ages

    Science.gov (United States)

    THE PATH TO TOBACCO ADDICTION STARTS AT VERY YOUNG AGES Lifetime smoking and other tobacco use almost always begins by the time kids graduate from ... regular smoking, which typically turns into a strong addiction—well before the age of 18—that can ...

  8. 76 FR 17736 - Major Capital Investment Program-New Starts

    Science.gov (United States)

    2011-03-30

    ... DEPARTMENT OF TRANSPORTATION Federal Transit Administration Major Capital Investment Program--New... unallocated Major Capital Investment (New Starts) program funds. The funds accelerate federal payments for new... projects. The funding will give a well-timed boost to communities that have made important investments in...

  9. A time-variant analysis of the 1/f^(2) phase noise in CMOS parallel LC-Tank quadrature oscillators

    DEFF Research Database (Denmark)

    Andreani, Pietro

    2006-01-01

    This paper presents a study of 1/f2 phase noise in quadrature oscillators built by connecting two differential LC-tank oscillators in a parallel fashion. The analysis clearly demonstrates the necessity of adopting a time-variant theory of phase noise, where a more simplistic, time...

  10. A new stochastic cellular automaton model on traffic flow and its jamming phase transition

    International Nuclear Information System (INIS)

    Sakai, Satoshi; Nishinari, Katsuhiro; Iida, Shinji

    2006-01-01

    A general stochastic traffic cellular automaton (CA) model, which includes the slow-to-start effect and driver's perspective, is proposed in this paper. It is shown that this model includes well-known traffic CA models such as the Nagel-Schreckenberg model, the quick-start model and the slow-to-start model as specific cases. Fundamental diagrams of this new model clearly show metastable states around the critical density even when the stochastic effect is present. We also obtain analytic expressions of the phase transition curve in phase diagrams by using approximate flow-density relations at boundaries. These phase transition curves are in excellent agreement with numerical results

  11. Time course of protein synthesis-dependent phase of olfactory memory in the cricket Gryllus bimaculatus.

    Science.gov (United States)

    Matsumoto, Yukihisa; Noji, Sumihare; Mizunami, Makoto

    2003-04-01

    The cricket Gryllus bimaculatus forms a stable olfactory memory that lasts for practically a lifetime. As a first step to elucidate the cellular mechanisms of olfactory learning and memory retention in crickets, we studied the dependency of memory retention on the de novo brain protein synthesis by injecting the protein synthesis inhibitor cycloheximide (CHX) into the head capsule. Injection of CHX inhibited (3)H-leucine incorporation into brain proteins by > 90% for 3 hr. Crickets were trained to associate peppermint odor with water (reward) and vanilla odor with saline solution (non-reward) and were injected with CHX before or at different times after training. Their odor preferences were tested at 2 hr, 1 day and 4 days after training. Memory retention at 2 hr after training was unaffected by CHX injection. However, the level of retention at 1 day and 4 days after training was lowered when CHX was injected 1 hour before training or at 1 hr or 6 hr after training. To study the time course of the development of CHX-sensitive memory phase, crickets that had been injected with CHX at 1 hr after training were tested at different times from 2 to 12 hr after training. The level of retention was unaffected up to 4 hr after training but significantly lowered at 5 hr after training, and the CHX-sensitive memory phase developed gradually during the next several hours. CHX dissociates two phases of olfactory memory in crickets: earlier protein synthesis-independent phase ( 5 hr) protein synthesis-dependent phase.

  12. Off-line phase-averaged particle image velocimetry and OH chemiluminescence measurements using acoustic time series

    International Nuclear Information System (INIS)

    Fischer, A; Bake, F; Heinze, J; Willert, C; Diers, O; Röhle, I

    2009-01-01

    In order to analyze unsteady flow phenomena in combustion facilities two phase-sorting methods have been developed and investigated for the retrieval of phase-resolved data from (randomly) sampled 'single-shot' data such as PIV recordings or chemiluminescence imagery in a post-processing step. This is made possible by simultaneously recorded continuous time traces of reference data (e.g., pressure signal). Using this off-line method synchronous phase-locked PIV and OH chemiluminescence visualizations could be recovered from data obtained in two different combustion facilities. This paper also presents some of the theoretical background necessary for the application of two different phase-sorting algorithms

  13. Topological phases in a three-dimensional topological insulator with a time-reversal invariant external field

    International Nuclear Information System (INIS)

    Guo, Xiaoyong; Ren, Xiaobin; Wang, Gangzhi; Peng, Jie

    2014-01-01

    We investigate the impact of a time-reversal invariant external field on the topological phases of a three-dimensional (3D) topological insulator. By taking the momentum k z as a parameter, we calculate the spin-Chern number analytically. It is shown that both the quantum spin Hall phase and the integer quantum Hall phase can be realized in our system. When the strength of the external field is varied, a series of topological phase transitions occurs with the closing of the energy gap or the spin-spectrum gap. In a tight-binding form, the surface modes are discussed numerically to confirm the analytically results. (paper)

  14. TFTR Mirnov coil analysis at plasma start-up

    International Nuclear Information System (INIS)

    Harley, T.R.; Buchenauer, D.A.; Coonrod, J.; McGuire, K.M.

    1986-01-01

    The methods for finding poloidal and toroidal numbers of MHD oscillations from Mirnov coils are reviewed and modified. Examples of various MHD phenomena occurring during start-up on TFTR are illustrated. It is found that the MHD mode structure best fits a model with the toroidal correction included. A new algorithm which finds m,n numbers can accommodate toroidal effects which are manifested in the phase data. The algorithm can find m,n numbers with a given toroidal correction parameter lambda', (lambda' = 0 → cylindrical). This algorithm is also used to find the optimal value of lambda' automatically, eliminating the need for ''guesswork.'' The algorithm finds the best parameters to the fit much faster than more conventional computational techniques. 9 refs., 21 figs., 2 tabs

  15. Experience from start-ups of the first ANITA Mox plants.

    Science.gov (United States)

    Christensson, M; Ekström, S; Andersson Chan, A; Le Vaillant, E; Lemaire, R

    2013-01-01

    ANITA™ Mox is a new one-stage deammonification Moving-Bed Biofilm Reactor (MBBR) developed for partial nitrification to nitrite and autotrophic N-removal from N-rich effluents. This deammonification process offers many advantages such as dramatically reduced oxygen requirements, no chemical oxygen demand requirement, lower sludge production, no pre-treatment or requirement of chemicals and thereby being an energy and cost efficient nitrogen removal process. An innovative seeding strategy, the 'BioFarm concept', has been developed in order to decrease the start-up time of new ANITA Mox installations. New ANITA Mox installations are started with typically 3-15% of the added carriers being from the 'BioFarm', with already established anammox biofilm, the rest being new carriers. The first ANITA Mox plant, started up in 2010 at Sjölunda wastewater treatment plant (WWTP) in Malmö, Sweden, proved this seeding concept, reaching an ammonium removal rate of 1.2 kgN/m³ d and approximately 90% ammonia removal within 4 months from start-up. This first ANITA Mox plant is also the BioFarm used for forthcoming installations. Typical features of this first installation were low energy consumption, 1.5 kW/NH4-N-removed, low N₂O emissions, started up at Sundets WWTP in Växjö, Sweden, reached full capacity with more than 90% ammonia removal within 2 months from start-up. By applying a nitrogen loading strategy to the reactor that matches the capacity of the seeding carriers, more than 80% nitrogen removal could be obtained throughout the start-up period.

  16. Comparison of crossover and jab step start techniques for base stealing in baseball.

    Science.gov (United States)

    Miyanishi, Tomohisa; Endo, So; Nagahara, Ryu

    2017-11-01

    Base stealing is an important tactic for increasing the chance of scoring in baseball. This study aimed to compare the crossover step (CS) and jab step (JS) starts for base stealing start performance and to clarify the differences between CS and JS starts in terms of three-dimensional lower extremity joint kinetics. Twelve male baseball players performed CS and JS starts, during which their motion and the force they applied to the ground were simultaneously recorded using a motion-capture system and two force platforms. The results showed that the normalised average forward external power, the average forward-backward force exerted by the left leg, and the forward velocities of the whole body centre of gravity generated by both legs and the left leg were significantly higher for the JS start than for the CS start. Moreover, the positive work done by hip extension during the left leg push-off was two-times greater for the JS start than the CS start. In conclusion, this study has demonstrated that the jab step start may be the better technique for a base stealing start and that greater positive work produced by left hip extension is probably responsible for producing its larger forward ground reaction force.

  17. Phase transition from strong-coupling expansion

    International Nuclear Information System (INIS)

    Polonyi, J.; Szlachanyi, K.

    1982-01-01

    Starting with quarkless SU(2) lattice gauge theory and using the strong-coupling expansion we calculate the action of the effective field theory which corresponds to the thermal Wilson loop. This effective action makes evident that the quark liberating phase transition traces back to the spontaneous breaking of a global Z(2) symmetry group. It furthermore describes both phases qualitatively. (orig.)

  18. The Relationship Between the Lower-Body Muscular Profile and Swimming Start Performance

    Directory of Open Access Journals (Sweden)

    García-Ramos Amador

    2016-04-01

    Full Text Available This study aimed to examine the correlation of different dry land strength and power tests with swimming start performance. Twenty international level female swimmers (age 15.3 ± 1.6 years, FINA point score 709.6 ± 71.1 performed the track freestyle start. Additionally, dry land tests were conducted: a squat (SJ and countermovement jumps (CMJ, b squat jumps with additional resistance equivalent to 25, 50, 75 and 100% of swimmers’ body weight [BW], and c leg extension and leg flexion maximal voluntary isometric contractions. Correlations between dry land tests and start times at 5, 10 and 15 m were quantified through Pearson’s linear correlation coefficients (r. The peak bar velocity reached during the jumps with additional resistance was the variable most correlated to swimming start performance (r = -0.57 to -0.66 at 25%BW; r = -0.57 to -0.72 at 50%BW; r = -0.59 to -0.68 at 75%BW; r = -0.50 to - 0.64 at 100%BW. A few significant correlations between the parameters of the SJ and the CMJ with times of 5 and 10 m were found, and none with the isometric variables. The peak velocity reached during jumps with external loads relative to BW was found a good indicator of swimming start performance.

  19. R/S method for evaluation of pollutant time series in environmental quality assessment

    Directory of Open Access Journals (Sweden)

    Bu Quanmin

    2008-12-01

    Full Text Available The significance of the fluctuation and randomness of the time series of each pollutant in environmental quality assessment is described for the first time in this paper. A comparative study was made of three different computing methods: the same starting point method, the striding averaging method, and the stagger phase averaging method. All of them can be used to calculate the Hurst index, which quantifies fluctuation and randomness. This study used real water quality data from Shazhu monitoring station on Taihu Lake in Wuxi, Jiangsu Province. The results show that, of the three methods, the stagger phase averaging method is best for calculating the Hurst index of a pollutant time series from the perspective of statistical regularity.

  20. Preschool Facilities - MDC_HeadStart

    Data.gov (United States)

    NSGIC Local Govt | GIS Inventory — A label (point) feature class of Head Start / Early Head Start/ Delegate Agencies/ Child Care Partnership & Family Day Care Homes Programs location in Miami-Dade...

  1. Sleep on Long Haul Layovers and Pilot Fatigue at the Start of the Next Duty Period.

    Science.gov (United States)

    Cosgrave, Jan; Wu, Lora J; van den Berg, Margo; Signal, T Leigh; Gander, Philippa H

    2018-01-01

    Layovers are critical for pilot recovery between flights and minimum layover durations are required by regulation. However, research on the factors affecting layover sleep and safety performance indicators (SPIs) before subsequent flights is relatively sparse. The present project combined data from 6 studies, including 8 long-range and 5 ultra-long range out-and-back trips across a range of different layover destinations (299 pilots in 4-person crews, 410 layovers, 1-3 d layover duration). Sleep was monitored via actigraphy from 3 d pre-trip to at least 3 d post-trip. Pilots rated their sleepiness (Karolinska Sleepiness Scale, KSS) and fatigue (Samn-Perelli scale, SP) at duty start for the inbound flight. Mixed model ANOVAs identified independent associations between fatigue and sleepiness SPIs and operational factors (domicile time of duty start for the inbound flight in six 4-h bins, layover duration, and total sleep time (TST) in the 24 h prior to inbound duty start). TST was greatest on layovers ending between 1200-1559 domicile time (time in the city from which the outbound flight departed) and TST was a significant predictor of both KSS and SP ratings at duty start for the inbound flight. TST in the 24 h prior to the inbound flight was greatest when duty start time allowed for the inclusion of a full domicile night time period. In this dataset, circadian end-time of layovers is a key determinant of pilot fatigue status at the beginning of the inbound duty period.Cosgrove J, Wu LJ, van den Berg M, Signal TL, Gander PH. Sleep on long haul layovers and pilot fatigue at the start of the next duty period. Aerosp Med Hum Perform. 2018; 89(1):19-25.

  2. Starting Hormone Therapy at Menopause Increases Breast Cancer Risk

    Science.gov (United States)

    According to a January 28, 2011 article in the Journal of the National Cancer Institute, women who start taking menopausal hormone therapy around the time of menopause have a higher risk of breast cancer than women who begin taking hormones a few years later.

  3. Tradeoff analysis for Dependable Real-Time Embedded Systems during the Early Design Phases

    DEFF Research Database (Denmark)

    Gan, Junhe

    Embedded systems are becoming increasingly complex and have tight competing constraints in terms of performance, cost, energy consumption, dependability, flexibility, security, etc. The objective of this thesis is to propose design methods and tools for supporting the tradeoff analysis of competing...... to processing elements, as well as the processor voltage and frequency levels for executing each task, such that transient faults are tolerated, the real-time constraints of the application are satisfied, and the energy consumed is minimized. In this thesis, we target the early design phases, when decisions...... have a high impact on the subsequent implementation choices. However, due to a lack of information, the early design phases are characterized by uncertainties, e.g., in the worst-case execution times (WCETs), in the functionality requirements, or in the hardware component costs. In this context, we...

  4. Lessons learnt during the design, construction and start-up phase of a molten salt testing facility

    International Nuclear Information System (INIS)

    Rodríguez-García, Margarita-Manuela; Herrador-Moreno, Miguel; Zarza Moya, Eduardo

    2014-01-01

    In 2010, CIEMAT (Centro de investigaciones energéticas medioambientales y tecnológicas) signed a turn-key contract to have an experimental plant for thermal storage using molten salts at its PSA (Plataforma Solar de Almeria) facilities. This plant was designed to evaluate components, instrumentation and operation strategies and to give support to the industry in the qualification and evaluation of components. During the design, construction and start-up phases of this plant, many different aspects regarding design, construction and commissioning have been learnt and these will contribute to the improvement of other plants. Among other tips explained in the paper, we recommend the use of venting valves to eliminate the water present in the system after the pressure test or released by the salts during the first melting. The selection of instrumentation with no electronic components near a heat source, thus preventing them from overheating, is also advisable. The heat exchanger design and dimensioning should take into account not only the thermal losses to the atmosphere and through pipes and supports, but any possible reduction in the heat exchange surface that could have detrimental consequences in the thermal performance. Special attention must be paid when dimensioning and installing the EHT and insulation because both components are decisive in the avoidance of plug formation. Its correct installation in valves and supports and the proper positioning of the temperature control sensors, i.e. where no other heat source can distort the readings, are crucial. Recommendations and strategies for the operation and shutdown of this experimental plant are being gathered for a future paper. -- Highlights: • Description of the experimental molten salt storage system built at CIEMAT. • Design technical considerations for an experimental molten salt storage plant. • Hints for piping and heat exchangers design and thermal losses calculation. • Recommendations for

  5. CrowdPhase: crowdsourcing the phase problem

    International Nuclear Information System (INIS)

    Jorda, Julien; Sawaya, Michael R.; Yeates, Todd O.

    2014-01-01

    The idea of attacking the phase problem by crowdsourcing is introduced. Using an interactive, multi-player, web-based system, participants work simultaneously to select phase sets that correspond to better electron-density maps in order to solve low-resolution phasing problems. The human mind innately excels at some complex tasks that are difficult to solve using computers alone. For complex problems amenable to parallelization, strategies can be developed to exploit human intelligence in a collective form: such approaches are sometimes referred to as ‘crowdsourcing’. Here, a first attempt at a crowdsourced approach for low-resolution ab initio phasing in macromolecular crystallography is proposed. A collaborative online game named CrowdPhase was designed, which relies on a human-powered genetic algorithm, where players control the selection mechanism during the evolutionary process. The algorithm starts from a population of ‘individuals’, each with a random genetic makeup, in this case a map prepared from a random set of phases, and tries to cause the population to evolve towards individuals with better phases based on Darwinian survival of the fittest. Players apply their pattern-recognition capabilities to evaluate the electron-density maps generated from these sets of phases and to select the fittest individuals. A user-friendly interface, a training stage and a competitive scoring system foster a network of well trained players who can guide the genetic algorithm towards better solutions from generation to generation via gameplay. CrowdPhase was applied to two synthetic low-resolution phasing puzzles and it was shown that players could successfully obtain phase sets in the 30° phase error range and corresponding molecular envelopes showing agreement with the low-resolution models. The successful preliminary studies suggest that with further development the crowdsourcing approach could fill a gap in current crystallographic methods by making it

  6. CrowdPhase: crowdsourcing the phase problem

    Energy Technology Data Exchange (ETDEWEB)

    Jorda, Julien; Sawaya, Michael R. [Institute for Genomics and Proteomics, 611 Charles Young Drive East, Los Angeles, CA 90095 (United States); Yeates, Todd O., E-mail: yeates@mbi.ucla.edu [Institute for Genomics and Proteomics, 611 Charles Young Drive East, Los Angeles, CA 90095 (United States); Molecular Biology Institute, 611 Charles Young Drive East, Los Angeles, CA 90095 (United States); University of California, 611 Charles Young Drive East, Los Angeles, CA 90095 (United States)

    2014-06-01

    The idea of attacking the phase problem by crowdsourcing is introduced. Using an interactive, multi-player, web-based system, participants work simultaneously to select phase sets that correspond to better electron-density maps in order to solve low-resolution phasing problems. The human mind innately excels at some complex tasks that are difficult to solve using computers alone. For complex problems amenable to parallelization, strategies can be developed to exploit human intelligence in a collective form: such approaches are sometimes referred to as ‘crowdsourcing’. Here, a first attempt at a crowdsourced approach for low-resolution ab initio phasing in macromolecular crystallography is proposed. A collaborative online game named CrowdPhase was designed, which relies on a human-powered genetic algorithm, where players control the selection mechanism during the evolutionary process. The algorithm starts from a population of ‘individuals’, each with a random genetic makeup, in this case a map prepared from a random set of phases, and tries to cause the population to evolve towards individuals with better phases based on Darwinian survival of the fittest. Players apply their pattern-recognition capabilities to evaluate the electron-density maps generated from these sets of phases and to select the fittest individuals. A user-friendly interface, a training stage and a competitive scoring system foster a network of well trained players who can guide the genetic algorithm towards better solutions from generation to generation via gameplay. CrowdPhase was applied to two synthetic low-resolution phasing puzzles and it was shown that players could successfully obtain phase sets in the 30° phase error range and corresponding molecular envelopes showing agreement with the low-resolution models. The successful preliminary studies suggest that with further development the crowdsourcing approach could fill a gap in current crystallographic methods by making it

  7. Getting started with Unity

    CERN Document Server

    Felicia, Patrick

    2013-01-01

    Getting Started with Unity is written in an easy-to-follow tutorial format.""Getting Started with Unity"" is for[ 3D game developers[/color] who would like to learn how to use Unity3D and become familiar with its core features. This book is also suitable for intermediate users who would like to improve their skills. No prior knowledge of Unity3D is required.

  8. Activities on the site during construction phase

    International Nuclear Information System (INIS)

    Fickel, O.F.

    1977-01-01

    A survey is given of the work done on the site from site-opening till turn over of the plant to the client. After a short introduction to time schedules, manpower on site, site facilities and civil work and constructions, the commissioning and trial operation phase is discussed in detail. This phase begins with finishing the assembly of individual systems and components and ends with the trial operation and the acceptance measurement. During this period the subsystems are started-up in a useful sequence, first from cold, then from hot conditions and are finally operated as a total with nuclear energy. The single steps are: a) commissioning of indivudal systems; b) hot functional test 1 (without fuels) c) baseline inspection at the reactor pressure vessel; d) hot functional test 2 (with fuels); e) preparation for first criticality; f) postcriticality test program; g) trial operation: h) acceptance measurement. (HP) [de

  9. Quantum Optics in Phase Space

    Science.gov (United States)

    Schleich, Wolfgang P.

    2001-04-01

    Quantum Optics in Phase Space provides a concise introduction to the rapidly moving field of quantum optics from the point of view of phase space. Modern in style and didactically skillful, Quantum Optics in Phase Space prepares students for their own research by presenting detailed derivations, many illustrations and a large set of workable problems at the end of each chapter. Often, the theoretical treatments are accompanied by the corresponding experiments. An exhaustive list of references provides a guide to the literature. Quantum Optics in Phase Space also serves advanced researchers as a comprehensive reference book. Starting with an extensive review of the experiments that define quantum optics and a brief summary of the foundations of quantum mechanics the author Wolfgang P. Schleich illustrates the properties of quantum states with the help of the Wigner phase space distribution function. His description of waves ala WKB connects semi-classical phase space with the Berry phase. These semi-classical techniques provide deeper insight into the timely topics of wave packet dynamics, fractional revivals and the Talbot effect. Whereas the first half of the book deals with mechanical oscillators such as ions in a trap or atoms in a standing wave the second half addresses problems where the quantization of the radiation field is of importance. Such topics extensively discussed include optical interferometry, the atom-field interaction, quantum state preparation and measurement, entanglement, decoherence, the one-atom maser and atom optics in quantized light fields. Quantum Optics in Phase Space presents the subject of quantum optics as transparently as possible. Giving wide-ranging references, it enables students to study and solve problems with modern scientific literature. The result is a remarkably concise yet comprehensive and accessible text- and reference book - an inspiring source of information and insight for students, teachers and researchers alike.

  10. The Adder Phenomenon Emerges from Independent Control of Pre- and Post-Start Phases of the Budding Yeast Cell Cycle.

    Science.gov (United States)

    Chandler-Brown, Devon; Schmoller, Kurt M; Winetraub, Yonatan; Skotheim, Jan M

    2017-09-25

    Although it has long been clear that cells actively regulate their size, the molecular mechanisms underlying this regulation have remained poorly understood. In budding yeast, cell size primarily modulates the duration of the cell-division cycle by controlling the G1/S transition known as Start. We have recently shown that the rate of progression through Start increases with cell size, because cell growth dilutes the cell-cycle inhibitor Whi5 in G1. Recent phenomenological studies in yeast and bacteria have shown that these cells add an approximately constant volume during each complete cell cycle, independent of their size at birth. These results seem to be in conflict, as the phenomenological studies suggest that cells measure the amount they grow, rather than their size, and that size control acts over the whole cell cycle, rather than specifically in G1. Here, we propose an integrated model that unifies the adder phenomenology with the molecular mechanism of G1/S cell-size control. We use single-cell microscopy to parameterize a full cell-cycle model based on independent control of pre- and post-Start cell-cycle periods. We find that our model predicts the size-independent amount of cell growth during the full cell cycle. This suggests that the adder phenomenon is an emergent property of the independent regulation of pre- and post-Start cell-cycle periods rather than the consequence of an underlying molecular mechanism measuring a fixed amount of growth. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Gentilly 2. Initial phase of operation

    International Nuclear Information System (INIS)

    Michel, B.; Region, M.; Dietrich, J.P.

    1984-01-01

    At the end of March 1983, the Gentilly 2 nuclear power station achieved full power for the first time. The power station then underwent its first week of stable operation at full power. This meant the end of the run up to full power testing period (Phase C). This period was to be followed by a planned shutdown of six weeks, devoted to maintenance and modification work. However, an inspection suggested that there was internal damage to the turbine, whose seriousness was confirmed during disassembly of one of the low-pressure stages. The repairs were completed in early September and five months after the shutdown had begun, the power station could be restarted. At this point, the on-power testing (phase D), the final stage in the commissioning of Gentilly 2, was begun. September 30, 1983 marked the start of commercial operation of the power station, which was to provide a large amount of energy to the grid during the 1983-1984 winter until the recent scheduled shutdown on April 22. In this paper, a list of problems encountered and analyze the experience acquired during the initial phase of operating the Gentilly 2 power station

  12. Bootstrap finance: the art of start-ups.

    Science.gov (United States)

    Bhide, A

    1992-01-01

    Entrepreneurship is more popular than ever: courses are full, policymakers emphasize new ventures, managers yearn to go off on their own. Would-be founders often misplace their energies, however. Believing in a "big money" model of entrepreneurship, they spend a lot of time trying to attract investors instead of using wits and hustle to get their ideas off the ground. A study of 100 of the 1989 Inc. "500" list of fastest growing U.S. start-ups attests to the value of bootstrapping. In fact, what it takes to start a business often conflicts with what venture capitalists require. Investors prefer solid plans, well-defined markets, and track records. Entrepreneurs are heavy on energy and enthusiasm but may be short on credentials. They thrive in rapidly changing environments where uncertain prospects may scare off established companies. Rolling with the punches is often more important than formal plans. Striving to adhere to investors' criteria can diminish the flexibility--the try-it, fix-it approach--an entrepreneur needs to make a new venture work. Seven principles are basic for successful start-ups: get operational fast; look for quick break-even, cash-generating projects; offer high-value products or services that can sustain direct personal selling; don't try to hire the crack team; keep growth in check; focus on cash; and cultivate banks early. Growth and change are the start-up's natural environment. But change is also the reward for success: just as ventures grow, their founders usually have to take a fresh look at everything again: roles, organization, even the very policies that got the business up and running.

  13. The study of 80 MHz self starting passively mode-locked Erbium-Doped Fiber Laser via nonlinear polarization rotation with SESAM

    International Nuclear Information System (INIS)

    Qamar, F.

    2013-01-01

    Erbium-Doped Fiber Laser, EDF L, passively mode-locked via only Nonlinear Polarization Rotation, NPR, and via NPR with Semiconductor Saturable Absorber Mirror, SESAM, is studied. Self start single pulse train with pulse width of 114 fs and repetition rate (PRR) of 80 MHz has been obtained when 55 cm EDFL, passively mode-locked via NPR only. Inserting SESAM in EDFL cavity leads to shorten the pulse width up to 88 fs, increases the amplitude stability up to 96% and lower the phase noise jittering to around 26 fsec. Stable second harmonic self starting passively mode-locked EDFL with pulse width of 284 fs has also been observed only when SESAM was used in the cavity. Multi-pulsed system passively mode-locked via NPR for EDFL length of 80 cm with time difference between the successive multi-pulses ranged from few picoseconds to nanoseconds, has been observed. The time difference can be controlled by the polarizer controller and the half wave plate. Further controlling of the cavity polarization leads to developing the multiple mode locking pulses train to second harmonic mode-locking pulse train with PRR of 160MHz and pulse width of 156 fs. Three harmonic superposed trains of mode locked pulse have been achieved only when SESAM added to the cavity. (author)

  14. Start-up and ramp-up of the PLT tokamak by lower hybrid waves

    International Nuclear Information System (INIS)

    Jobes, F.C.; Bernabei, S.; Chu, T.K.

    1985-08-01

    Lower hybrid waves have been used on the PLT tokamak both to start the plasma current and to ramp it up from pre-existing levels. The waves, at 800 MHz, were launched from a 6-waveguide grill. The phasing between adjacent guides could be selected electronically, and thus the launched spectrum could be set and changed at will. For start-up, the waveguide phase difference was initially set at 0 0 in order to create a plasma, then switched to 90 0 to drive the current. Over 100 kA of plasma current, at a density of 0.5 to 1 x 10 12 cm -3 , was generated in this manner. Ramp-up experiments were performed under a wide variety of conditions. The most efficient ramp-up was found at the lowest plasma densities and with the fastest launched spectrum (n/sub e/ approx. 2 x 10 12 cm -3 , N/sub parallel/ approx. 1.6 peak); approx.20% of the launched RF power was converted to (increased) poloidal field energy. All of the ramp-up results are in excellent agreement with a theory which determines the efficiency of ramp-up from the consideration of the relative energy losses of the superthermal current-carrying electrons to collisions and to the opposing inductive E-field

  15. Relationship Between Vertical Jump Height and Swimming Start Performance Before and After an Altitude Training Camp.

    Science.gov (United States)

    García-Ramos, Amador; Padial, Paulino; de la Fuente, Blanca; Argüelles-Cienfuegos, Javier; Bonitch-Góngora, Juan; Feriche, Belén

    2016-06-01

    This study aimed (a) to analyze the development in the squat jump height and swimming start performance after an altitude training camp, (b) to correlate the jump height and swimming start performance before and after the altitude training period, and (c) to correlate the percent change in the squat jump height with the percent change in swimming start performance. Fifteen elite male swimmers from the Spanish Junior National Team (17.1 ± 0.8 years) were tested before and after a 17-day training camp at moderate altitude. The height reached in the squat jump exercise with additional loads of 0, 25, 50, 75, and 100% of swimmers' pretest body weight and swimming start performance (time to 5, 10, and 15 m) were the dependent variables analyzed. Significant increases in the jump height (p ≤ 0.05; effect size [ES]: 0.35-0.48) and swimming start performance (p jump height before training (r = -0.56 to -0.77) and after training (r = -0.50 to -0.71). The change in the squat jump height was inversely correlated with the change in the start time at 5 m (r = -0.47), 10 m (r = -0.73), and 15 m (r = -0.62). These results suggest that altitude training can be suitable to enhance explosive performance. The correlations obtained between the squat jump height and start time in the raw and change scores confirm the relevance of having high levels of lower-body muscular power to optimize swimming start performance.

  16. Starting-up sequence of the AWEC-6 0 wind turbine

    International Nuclear Information System (INIS)

    Avia, F.; Cruz, M. de la

    1991-01-01

    One of the most critical status of the wind turbines operation is the starting-up sequence and the connection to the grid, due to the actuating loads that could be several times the loads during operation at rated conditions. Due to this fact, the control strategy is very important during the starting-up sequence in order to minimize the loads on the machine. For this purpose it is necessary to analyze the behaviour of the wind turbine during that sequence in different wind conditions and machine conditions This report shows the graphic Information about fifty starting-up sequences of the AWEC-60 wind turbine of 60 m diameter and 1200 kW of rated power, recorded in April 1991 and covering all the operation range between cut-in and cut-out wind speed. (Author) 2 refs

  17. Non-commutative phase space and its space-time symmetry

    International Nuclear Information System (INIS)

    Li Kang; Dulat Sayipjamal

    2010-01-01

    First a description of 2+1 dimensional non-commutative (NC) phase space is presented, and then we find that in this formulation the generalized Bopp's shift has a symmetric representation and one can easily and straightforwardly define the star product on NC phase space. Then we define non-commutative Lorentz transformations both on NC space and NC phase space. We also discuss the Poincare symmetry. Finally we point out that our NC phase space formulation and the NC Lorentz transformations are applicable to any even dimensional NC space and NC phase space. (authors)

  18. Starting out

    NARCIS (Netherlands)

    Ans Merens; Freek Bucx

    2018-01-01

    Original title: Werken aan de start Women in the Netherlands have been outperforming men in education for many years now. However, this superior educational achievement does not translate into a better position on the labour market. More women work today than in the past, but still fewer than men.

  19. Start 2: Thinking one move ahead

    Energy Technology Data Exchange (ETDEWEB)

    Gaines, L.L.

    1991-11-01

    At their summit meeting in the spring of 1990, Presidents Bush and Gorbachev issued a joint statement expressing their intentions to continue the process of strategic arms control beyond the Strategic Arms Reduction Treaty (START), which was eventually signed in July 1991, toward agreement on further reductions. They set general goals for negotiation of a follow-on treaty to START, which has been called START II. President Bush`s historic speech on September 27, 1991, reinforced those goals and specified several actions the US would take. It is the purpose of this report to examine possible provisions of START II and the implications of those provisions for achievement of the goals set at the 1990 summit, for verifiability, and for US force planning. This look ahead will contribute to advance planning of appropriate negotiating positions, verification research and development (R&D), and force modernization and restructuring. This report describes the goals for a START II treaty and possible means for achieving them. It postulates one set of provisions for such a treaty, while it examines force structures for the US that could result from adoption of a treaty with these provisions. The adequacy of methods for verifying START II are examined and the implications of a START II treaty are postulated.

  20. Start 2: Thinking one move ahead

    Energy Technology Data Exchange (ETDEWEB)

    Gaines, L.L.

    1991-11-01

    At their summit meeting in the spring of 1990, Presidents Bush and Gorbachev issued a joint statement expressing their intentions to continue the process of strategic arms control beyond the Strategic Arms Reduction Treaty (START), which was eventually signed in July 1991, toward agreement on further reductions. They set general goals for negotiation of a follow-on treaty to START, which has been called START II. President Bush's historic speech on September 27, 1991, reinforced those goals and specified several actions the US would take. It is the purpose of this report to examine possible provisions of START II and the implications of those provisions for achievement of the goals set at the 1990 summit, for verifiability, and for US force planning. This look ahead will contribute to advance planning of appropriate negotiating positions, verification research and development (R D), and force modernization and restructuring. This report describes the goals for a START II treaty and possible means for achieving them. It postulates one set of provisions for such a treaty, while it examines force structures for the US that could result from adoption of a treaty with these provisions. The adequacy of methods for verifying START II are examined and the implications of a START II treaty are postulated.

  1. Dynamic factors and electromyographic activity in a sprint start

    Directory of Open Access Journals (Sweden)

    M Čoh

    2009-07-01

    Full Text Available The aim of the study was to establish the major dynamic parameters as well as the EMG activation of muscles in a sprint start as the first derivative of sprint velocity. The subject of the analysis was block velocity, the production of force in the front and rear starting blocks, the block acceleration in the first two steps and the electromyographic activity (EMG of the following muscles: the erector spinae muscle, gluteus maximus muscle, rectus femoris muscle, vastus medialis muscle, vastus lateralis muscle, biceps femoris muscle and gastrocnemius–medialis muscle. One international-class female sprinter participated in the experiment. She performed eight starts in constant laboratory conditions. The 3-D kinematic analysis was made using a system of nine Smart-e 600 cameras operating at a frame rate of 60 Hz. Dynamic parameters were established by means of two separate force platforms to which the starting blocks were fixed. A 16-channel electromyograph was used to analyse electromyographic activity (EMG. It was established that the block velocity depended on the absolute force produced in the front and rear starting blocks and that it was 2.84±0.21 m.s-1. The maximal force on the rear and front blocks was 628±34 N and 1023±30 N, respectively. In view of the total impulse (210±11 Ns the force production/time ratio in the rear and front blocks was 34%:66%. The erector spinae muscle, vastus lateralis muscle and gastrocnemius–medialis muscle generate the efficiency of the start. The block acceleration in the first two steps primarily depends on the activation of the gluteus maximus muscle, rectus femoris muscle, biceps femoris muscle and gastrocnemius–medialis muscle. A sprint start is a complex motor stereotype requiring a high degree of integration of the processes of central movement regulation and an optimal level of biomotor abilities.

  2. Polling Systems with Two-Phase Gated Service: Heavy Traffic Results for the Waiting Time Distribution

    NARCIS (Netherlands)

    R.D. van der Mei (Rob); J.A.C. Resing

    2008-01-01

    htmlabstractWe study an asymmetric cyclic polling system with Poisson arrivals, general service-time and switch-over time distributions, and with so-called two-phase gated service at each queue, an interleaving scheme that aims to enforce some level of "fairness" among the different customer

  3. Dynamic phase diagrams of a cylindrical Ising nanowire in the presence of a time dependent magnetic field

    International Nuclear Information System (INIS)

    Kantar, Ersin; Ertaş, Mehmet; Keskin, Mustafa

    2014-01-01

    The dynamic phase diagrams of a cylindrical Ising nanowire in the presence of a time dependent magnetic field are obtained by using the effective-field theory with correlations based on the Glauber-type stochastic dynamics. According to the values of interaction parameters, a number of interesting properties have been found in the dynamic phase diagrams, such as many dynamic critical points (tricritical point, double critical end point, critical end point, zero temperature critical point, multicritical point, tetracritical point, and triple point) as well as reentrant phenomena. - Highlights: • The cylindrical Ising nanowire is investigated within the Glauber dynamics based on EFT. • The time variations of average order parameters to find phases are studied. • The dynamic phase diagrams are found for the different interaction parameters. • The system displays the critical points as well as a reentrant behavior

  4. Dynamic phase diagrams of a cylindrical Ising nanowire in the presence of a time dependent magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Kantar, Ersin; Ertaş, Mehmet, E-mail: mehmetertas@erciyes.edu.tr; Keskin, Mustafa

    2014-06-01

    The dynamic phase diagrams of a cylindrical Ising nanowire in the presence of a time dependent magnetic field are obtained by using the effective-field theory with correlations based on the Glauber-type stochastic dynamics. According to the values of interaction parameters, a number of interesting properties have been found in the dynamic phase diagrams, such as many dynamic critical points (tricritical point, double critical end point, critical end point, zero temperature critical point, multicritical point, tetracritical point, and triple point) as well as reentrant phenomena. - Highlights: • The cylindrical Ising nanowire is investigated within the Glauber dynamics based on EFT. • The time variations of average order parameters to find phases are studied. • The dynamic phase diagrams are found for the different interaction parameters. • The system displays the critical points as well as a reentrant behavior.

  5. Start To End Simulation for the SPARX Project

    CERN Document Server

    Vaccarezza, Cristina; Boscolo, Manuela; Ferrario, Massimo; Fusco, Valeria; Giannessi, Luca; Migliorati, Mauro; Palumbo, Luigi; Quattromini, Marcello; Ronsivalle, Concetta; Serafini, Luca; Spataro, Bruno; Vescovi, Mario

    2005-01-01

    The first phase of the SPARX project now funded by Government Agencies, is an R&D activity focused on developing techniques and critical components for future X-ray facilities. The aim is the generation of electron beams with the ultra-high peak brightness required to drive FEL experiments. The FEL source realization will develop along two lines: (a) the use of the SPARC high brightness photoinjector to test RF compression techniques and the emittance degradation in magnetic compressors due to CSR, (b) the production of radiation in the range of 3-5 nm, both in SASE and SEEDED FEL configurations, in the so called SPARXINO test facility, upgrading the existing Frascati 800 MeV LINAC. In this paper we present and discuss the preliminary start to end simulations results.

  6. Label-free cell-cycle analysis by high-throughput quantitative phase time-stretch imaging flow cytometry

    Science.gov (United States)

    Mok, Aaron T. Y.; Lee, Kelvin C. M.; Wong, Kenneth K. Y.; Tsia, Kevin K.

    2018-02-01

    Biophysical properties of cells could complement and correlate biochemical markers to characterize a multitude of cellular states. Changes in cell size, dry mass and subcellular morphology, for instance, are relevant to cell-cycle progression which is prevalently evaluated by DNA-targeted fluorescence measurements. Quantitative-phase microscopy (QPM) is among the effective biophysical phenotyping tools that can quantify cell sizes and sub-cellular dry mass density distribution of single cells at high spatial resolution. However, limited camera frame rate and thus imaging throughput makes QPM incompatible with high-throughput flow cytometry - a gold standard in multiparametric cell-based assay. Here we present a high-throughput approach for label-free analysis of cell cycle based on quantitative-phase time-stretch imaging flow cytometry at a throughput of > 10,000 cells/s. Our time-stretch QPM system enables sub-cellular resolution even at high speed, allowing us to extract a multitude (at least 24) of single-cell biophysical phenotypes (from both amplitude and phase images). Those phenotypes can be combined to track cell-cycle progression based on a t-distributed stochastic neighbor embedding (t-SNE) algorithm. Using multivariate analysis of variance (MANOVA) discriminant analysis, cell-cycle phases can also be predicted label-free with high accuracy at >90% in G1 and G2 phase, and >80% in S phase. We anticipate that high throughput label-free cell cycle characterization could open new approaches for large-scale single-cell analysis, bringing new mechanistic insights into complex biological processes including diseases pathogenesis.

  7. Teaching iSTART to Understand Spanish

    Science.gov (United States)

    Dascalu, Mihai; Jacovina, Matthew E.; Soto, Christian M.; Allen, Laura K.; Dai, Jianmin; Guerrero, Tricia A.; McNamara, Danielle S.

    2017-01-01

    iSTART is a web-based reading comprehension tutor. A recent translation of iSTART from English to Spanish has made the system available to a new audience. In this paper, we outline several challenges that arose during the development process, specifically focusing on the algorithms that drive the feedback. Several iSTART activities encourage…

  8. Time delay and duration of ionospheric total electron content responses to geomagnetic disturbances

    Directory of Open Access Journals (Sweden)

    J. Liu

    2010-03-01

    Full Text Available Although positive and negative signatures of ionospheric storms have been reported many times, global characteristics such as the time of occurrence, time delay and duration as well as their relations to the intensity of the ionospheric storms have not received enough attention. The 10 years of global ionosphere maps (GIMs of total electron content (TEC retrieved at Jet Propulsion Laboratory (JPL were used to conduct a statistical study of the time delay of the ionospheric responses to geomagnetic disturbances. Our results show that the time delays between geomagnetic disturbances and TEC responses depend on season, magnetic local time and magnetic latitude. In the summer hemisphere at mid- and high latitudes, the negative storm effects can propagate to the low latitudes at post-midnight to the morning sector with a time delay of 4–7 h. As the earth rotates to the sunlight, negative phase retreats to higher latitudes and starts to extend to the lower latitude toward midnight sector. In the winter hemisphere during the daytime and after sunset at mid- and low latitudes, the negative phase appearance time is delayed from 1–10 h depending on the local time, latitude and storm intensity compared to the same area in the summer hemisphere. The quick response of positive phase can be observed at the auroral area in the night-side of the winter hemisphere. At the low latitudes during the dawn-noon sector, the ionospheric negative phase responses quickly with time delays of 5–7 h in both equinoctial and solsticial months.

    Our results also manifest that there is a positive correlation between the intensity of geomagnetic disturbances and the time duration of both the positive phase and negative phase. The durations of both negative phase and positive phase have clear latitudinal, seasonal and magnetic local time (MLT dependence. In the winter hemisphere, long durations for the positive phase are 8–11 h and 12–14 h during the daytime at

  9. Time delay and duration of ionospheric total electron content responses to geomagnetic disturbances

    Directory of Open Access Journals (Sweden)

    J. Liu

    2010-03-01

    Full Text Available Although positive and negative signatures of ionospheric storms have been reported many times, global characteristics such as the time of occurrence, time delay and duration as well as their relations to the intensity of the ionospheric storms have not received enough attention. The 10 years of global ionosphere maps (GIMs of total electron content (TEC retrieved at Jet Propulsion Laboratory (JPL were used to conduct a statistical study of the time delay of the ionospheric responses to geomagnetic disturbances. Our results show that the time delays between geomagnetic disturbances and TEC responses depend on season, magnetic local time and magnetic latitude. In the summer hemisphere at mid- and high latitudes, the negative storm effects can propagate to the low latitudes at post-midnight to the morning sector with a time delay of 4–7 h. As the earth rotates to the sunlight, negative phase retreats to higher latitudes and starts to extend to the lower latitude toward midnight sector. In the winter hemisphere during the daytime and after sunset at mid- and low latitudes, the negative phase appearance time is delayed from 1–10 h depending on the local time, latitude and storm intensity compared to the same area in the summer hemisphere. The quick response of positive phase can be observed at the auroral area in the night-side of the winter hemisphere. At the low latitudes during the dawn-noon sector, the ionospheric negative phase responses quickly with time delays of 5–7 h in both equinoctial and solsticial months. Our results also manifest that there is a positive correlation between the intensity of geomagnetic disturbances and the time duration of both the positive phase and negative phase. The durations of both negative phase and positive phase have clear latitudinal, seasonal and magnetic local time (MLT dependence. In the winter hemisphere, long durations for the positive phase are 8–11 h and 12–14 h during the daytime at middle

  10. Time evolution and dynamical phase transitions at a critical time in a system of one-dimensional bosons after a quantum quench.

    Science.gov (United States)

    Mitra, Aditi

    2012-12-28

    A renormalization group approach is used to show that a one-dimensional system of bosons subject to a lattice quench exhibits a finite-time dynamical phase transition where an order parameter within a light cone increases as a nonanalytic function of time after a critical time. Such a transition is also found for a simultaneous lattice and interaction quench where the effective scaling dimension of the lattice becomes time dependent, crucially affecting the time evolution of the system. Explicit results are presented for the time evolution of the boson interaction parameter and the order parameter for the dynamical transition as well as for more general quenches.

  11. Are separate-phase thermal-hydraulic models better than mixture-fluid approaches? It depends. Rather not

    International Nuclear Information System (INIS)

    Hoeld, A.

    2004-01-01

    The thermal-hydraulic theory of single- and especially two-phase flow systems used for plant transient analysis is dominated by separate-phase models. The corresponding mostly very comprehensive codes (TRAC, RELAP, CATHARE, ATHLET etc.) are looked as to be by far more efficient than a 3 eq. mixture-fluid approach and code also if they show deficiencies in describing flow situations within inner loops as for example the distribution into parallel channels (and thus the simulation of 3D thermal-hydraulic phenomena). This may be justified if comparing them to the very simple 'homogeneous equilibrium models (HEM)', but not if looking to the more refined non-homogeneous 'separate-region' mixture-fluid approaches based on appropriate drift-flux correlation packages which can have, on the contrary, enormous advantages with respect to such separate-phase models. Especially if comparing the basic (and starting) eqs. of such theoretical models of both types the differences are remarkable. Single-phase and mixture-fluid models start from genuine conservation eqs. for mass, energy and momentum, demanding (in case of two-phase flow) additionally an adequate drift flux package (in order to get a relation for a fourth independent variable), a heat transfer coefficients package (over the whole range of the possible fields of application) and correlations for single- and two-phase friction. The other types of models are looking at each phase separately with corresponding 'field' eqs. for each phase, connected by exchange (=closure) terms which substitute the classical constitutive packages for drift, heat transfer and friction. That the drift-flux, heat transfer into a coolant channel and friction along a wall and between the phases is described better by a separate-phase approach is at least doubtful. The corresponding mixture-fluid correlations are based over a wide range on a treasure of experience and measurements, their pseudo-stationary treatment can (due to their small time

  12. Report of blind start-up experiments carried out on the reactor Cabri between 4. and 8. July 1966

    International Nuclear Information System (INIS)

    Filipczak, N.; Filipczak, W.; Furet, J.; Kaiser, J.

    1967-01-01

    The blind start-up of a reactor without any neutronic data concerning a relatively wide range of power dynamics can be necessary when difficulties arise in the positioning of the detector or in neutron-gamma discrimination near the multiplying medium. The object of the experiments carried out on the reactor Cabri was to check the very complete analysis of the start-up accident which was studied on an analogue computer. The number of experiments carried out (12) is not sufficient to allow a definite conclusion. Nevertheless the blind start-up method advocated by N. FILIPCZAK and W. FILIPCZAK does not appear to be incompatible with the security during the operational phase (on condition that its dynamic characteristics are close to that of the reactor Cabri). (authors) [fr

  13. 46 CFR 112.50-3 - Hydraulic starting.

    Science.gov (United States)

    2010-10-01

    ... POWER SYSTEMS Emergency Diesel and Gas Turbine Engine Driven Generator Sets § 112.50-3 Hydraulic starting. A hydraulic starting system must meet the following: (a) The hydraulic starting system must be a... 46 Shipping 4 2010-10-01 2010-10-01 false Hydraulic starting. 112.50-3 Section 112.50-3 Shipping...

  14. Study of effect of sintering time on the 2223 phase growth Bi-Pb-Sr-Ca-Cu-O superconductor by Rietveld method

    International Nuclear Information System (INIS)

    Parikin; Prasuad, W; Gunawan

    1996-01-01

    It has been reported that the sintering time is as important for the preparation of superconductor as the sintering temperature and method. This paper reports on the finding of the optimum sintering time in the preparation of the 2223 phase bismuth (Bi) superconductor. The samples were synthesized with nominal composition 1.84 : 0.34 : 1.91 : 2.03 : 3.06 from raw materials by solid state reaction and sintered at 860 o C for five days. The resintering were done three times, i.e. 24, 48 and 96 hours. The Rietveld analysis shows that the 2223 phase grows continuously as a function of the sintering time. The highest percentage of the 2223 phase (80.64%) were obtained at 96 hours sintering time. The result suggests that the 2223 phase can be obtained effectively by sintering with sufficiently long time

  15. Atomic disorder, phase transformation, and phase restoration in Co3Sn2

    Science.gov (United States)

    di, L. M.; Zhou, G. F.; Bakker, H.

    1993-03-01

    The behavior of the intermetallic compound Co3Sn2 upon ball milling was studied by x-ray diffraction, high-field-magnetization measurements, and subsequently by differential scanning calorimetry. It turns out that starting from the stoichiometric-ordered compound, mechanical attrition of Co3Sn2 generates atomic disorder in the early stage of milling. The nonequilibrium phase transformation from the low-temperature phase with orthorhombic structure to the high-temperature phase with a hexagonal structure was observed in the intermediate stage of milling. It was accompanied by the creation of increasing atomic disorder. After long milling periods, the phase transformation was completed and the atomic disordering became saturated. All the physical parameters measured in the present work remained constant during this period. The above outcome was confirmed by comparison with the high-temperature phase thermally induced by quenching. The good agreement of the results obtained by different techniques proves that the ball milling generates well-defined metastable states in Co3Sn2.

  16. Temperature gradient method for lipid phase diagram construction using time-resolved x-ray diffraction

    International Nuclear Information System (INIS)

    Caffrey, M.; Hing, F.S.

    1987-01-01

    A method that enables temperature-composition phase diagram construction at unprecedented rates is described and evaluated. The method involves establishing a known temperature gradient along the length of a metal rod. Samples of different compositions contained in long, thin-walled capillaries are positioned lengthwise on the rod and equilibrated such that the temperature gradient is communicated into the sample. The sample is then moved through a focused, monochromatic synchrotron-derived x-ray beam and the image-intensified diffraction pattern from the sample is recorded on videotape continuously in live-time as a function of position and, thus, temperature. The temperature at which the diffraction pattern changes corresponds to a phase boundary, and the phase(s) existing (coexisting) on either side of the boundary can be identified on the basis of the diffraction pattern. Repeating the measurement on samples covering the entire composition range completes the phase diagram. These additional samples can be conveniently placed at different locations around the perimeter of the cylindrical rod and rotated into position for diffraction measurement. Temperature-composition phase diagrams for the fully hydrated binary mixtures, dimyristoylphosphatidylcholine (DMPC)/dipalmitoylphosphatidylcholine (DPPC) and dipalmitoylphosphatidylethanolamine (DPPE)/DPPC, have been constructed using the new temperature gradient method. They agree well with and extend the results obtained by other techniques. In the DPPE/DPPC system structural parameters as a function of temperature in the various phases including the subgel phase are reported. The potential limitations of this steady-state method are discussed

  17. Both bias and lack of knowledge influence organizational focus on first case of the day starts.

    Science.gov (United States)

    Dexter, Elisabeth U; Dexter, Franklin; Masursky, Danielle; Garver, Michael P; Nussmeier, Nancy A

    2009-04-01

    The economic costs of reducing first case delays are often high, because efforts need to be applied to multiple operating rooms (ORs) simultaneously. Nevertheless, delays in starting first cases of the day are a common topic in OR committee meetings. We added three scientific questions to a 24 question online, anonymous survey performed before the implementation of a new OR information system. The 57 respondents cared sufficiently about OR management at the United States teaching hospital to complete all questions. The survey revealed reasons why personnel may focus on the small reductions in nonoperative time achievable by reducing tardiness in first cases of the day. (A) Respondents lacked knowledge about principles in reducing over-utilized OR time to increase OR efficiency, based on their answering the relevant question correctly at a rate no different from guessing at random. Those results differed from prior findings of responses at a rate worse than random, resulting from a bias on the day of surgery of making decisions that increase clinical work per unit time. (B) Most respondents falsely believed that a 10 min delay at the start of the day causes subsequent cases to start at least 10 min late (P less time than scheduled (P = 0.008 versus chance). No one who demonstrated knowledge (C) about cases sometimes taking less time than scheduled applied that information to their response to (B) regarding cases starting late (P = 0.0002). Knowledge of OR efficiency was low among the respondents working in ORs. Nevertheless, the apparent absence of bias shows that education may influence behavior. In contrast, presence of bias on matters of tardiness of start times shows that education may be of no benefit. As the latter results match findings of previous studies of scheduling decisions, interventions to reduce patient and surgeon waiting from start times may depend principally on the application of automation to guide decision-making.

  18. Time-resolved x-ray diffraction from frog skeletal muscle during shortening against an inertial load and a quick release

    International Nuclear Information System (INIS)

    Amemiya, Yoshiyuki; Hashizume, Hiroo; Tameyasu, Tsukasa; Tanaka, Hidehiro; Sugi, Haruo.

    1980-01-01

    A group of Japanese researchers conducted, for the first time in this field, experiments on time-resolved x-ray diffraction of frog (bullfrog, Rana catesbeiana) skeletal muscle in conditions where both the force and the muscle length change with time. During an isotonic twitch under a load of about 0.3 P 0 , the intensity ratio started falling on stimulation and reached a minimum value of 0.5 - 0.6 at the early shortening phase, which was maintained until the beginning of relaxation. Except that the minimum value was not retained until the start of relaxation, the same was observed during a twitch against an inertial load whereby the peak force exerted by the muscle was about 0.4 P 0 . The results may be taken to indicate that the change in the intensity ratio reflects not the time course of shortening but that of force generation. When a quick release (3 - 4% of muscle length) was applied during the rising phase of an isometric twitch, the intensity ratio showed no distinct change. Judging from tentative calculation results, however, the foregoing result is subject to further experiments with a much improved time resolution of the measurements. (Kitajima, A.)

  19. Oscillatory solitons and time-resolved phase locking of two polariton condensates

    International Nuclear Information System (INIS)

    Christmann, Gabriel; Tosi, Guilherme; Baumberg, Jeremy J; Berloff, Natalia G; Tsotsis, Panagiotis; Eldridge, Peter S; Hatzopoulos, Zacharias; Savvidis, Pavlos G

    2014-01-01

    When pumped nonresonantly, semiconductor microcavity polaritons form Bose–Einstein condensates that can be manipulated optically. Using tightly-focused excitation spots, radially expanding condensates can be formed in close proximity. Using high time resolution streak camera measurements we study the time dependent properties of these macroscopic coherent states. By coupling this method with interferometry we observe directly the phase locking of two independent condensates in time, showing the effect of polariton–polariton interactions. We also directly observe fast spontaneous soliton-like oscillations of the polariton cloud trapped between the pump spots, which can be either dark or bright solitons. This transition from dark to bright is a consequence of the change of sign of the nonlinearity which we propose is due to the shape of the polariton dispersion leading to either positive or negative polariton effective mass. (paper)

  20. Characterization for solidification and phase transformations of pure-titanium steel weld metal with time-resolved X-ray diffraction system

    International Nuclear Information System (INIS)

    Terasaki, Hidenori; Komizo, Yu-ichi; Nishino, Fumihiro; Ikeda, Masahiko

    2007-01-01

    Understanding and controlling solidification and phase transformation process of weld metal is essential for forming the microstructure with superior mechanical property. Recent evolution of analysis technique makes for solidification and phase transformation process to be in-situ analyzed, in direct and reciprocal lattice space. In the present work, unidirectional-solidification and phase transformation in the weld metal of commercial pure-titanium in Gas Tungsten Arc welding was in-situ observed by using Time-Resolved X-Ray Diffraction system with two-dimensional pixel detector. An undulator beam was used as a probe. Larger diffraction area could be detected in the time-resolution of 0.05 seconds, in unidirectional solidification and subsequent phase transformation process of pure-titanium weld metal. Furthermore, the microstructure formation during β-α phase transformation was in situ observed with High temperature Laser Scanning Confocal Microscopy. The crystal configurations in unidirectional solidification of weld metal and rapid change of phase ratio in reconstructive phase transformation were clearly analyzed. (author)