• Title/Summary/Keyword: Repetition effect

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Effect of Laser Pulse Repetition Rate on the Electrical Properties of $Pb(Zr_{0.48}Ti_{0.52})O_3$ (PZT) Thin Films grown by Pulsed Laser Deposition (펄스 레이저 증착법에 의해 제작된 Laser pulse repetition rate의 변화에 따른 $Pb(Zr_{0.48}Ti_{0.52})O_3$ (PZT) 박막의 전기적 특성)

  • Li, Dong-Hua;Lee, Sang-Yeol
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.11a
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    • pp.11-12
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    • 2005
  • [ $Pb(Zr_{0.48}Ti_{0.52})O_3$ ] (PZT) thin films were deposited on Pt(111)/Ti/$SiO_2$/Si substrates by pulsed laser deposition. In order to study the effect of different laser pulse repetition rate on the dielectric and ferroelectric properties of PZT thin films,2 Hz and 5 Hz of laser pulse repetition rate were selected. We compared the results of XRD pattern, dielectric constant and hysteresis characteristics. From the experimental data, we found that the electrical properties of PZT thin films which grown ar 2 Hz of laser pulse repetition rate were better than those which grown at 5 Hz of laser pulse repetition rate.

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Psychophysical Stess Depending on Repetition of Wrist Motion and External Load (손목 동작의 반복과 외부 부하에 따른 심물리학적 부하)

  • Kee, Do-Hyung
    • Journal of the Korean Society of Safety
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    • v.19 no.4 s.68
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    • pp.123-128
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    • 2004
  • This study investigated effect of arm posture, repetition of wrist motion and external load on perceived discomfort. The arm postures were controlled by shoulder flexion, elbow flexion, and ist motions such as flexion, extension, radial deviation and ulnar deviation. An experiment was conducted to measure discomfort scores for experimental treatments using the magnitude estimation, in which the L16 orthogonal array was adopted for reducing the size of experiment. The results showed that while the effect of the shoulder flexion, repetition of wrist motion and external load was statistically significant at $\alpha=0.05$or 0.10, that of the elbow and wrist motions was not. Discomfor ratings increased linearly as levels of wrist repetition and external load increased. This implies that the existing posture classification schemes such as OWAS, RULA, which do not properly consider effect of motion repetition and external load, may underestimate postural load. Based on the regression equation for wrist repetition and external load, isocomfort region indicating the region within which discomfort scores were expected to be the same was proposed. It is recommended that when assessing risk of postures or developing new posture classification schemes, motion repetition and external load as well as posture itself be fully taken into consideration for precisely evaluating postural stress.

Learning Outcomes Analysis Using by Degree of Concept and Repetition Learning of Motion Mechanics (운동 역학의 개념형성 정도와 재학습을 통한 학습효과 분석)

  • Jang, Seok-Jeong;Lee, Jongkil
    • The Journal of Korean Institute for Practical Engineering Education
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    • v.4 no.2
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    • pp.46-52
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    • 2012
  • In this study, middle school students, from 1st to 3rd grade, who already completed section of the 'force and motion' are targets. Based on the survey of the students following conclusions are obtained using by 'before and after' of repetition learning. First, through the pre-test results and measured the degree of concept, repetition learning was found to be effective. Second, through the post-survey after repetition learning science concerning was increased rather than before learning. Improved confidence through the repetition learning effect should contribute learning effect.

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Psychophysical Load for Females Depending on Arm Posture, Repetition of Wrist Motion and External Load (여성의 팔 자세, 손목 동작 반복과 외부 부하에 따른 심물리학적 부하)

  • Kee, Do-Hyung
    • Journal of the Korean Society of Safety
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    • v.21 no.3 s.75
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    • pp.122-126
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    • 2006
  • This study investigated effect of arm posture, wrist motion repetition and external load on perceived discomfort through an experiment. Eleven female college students participated in the experiment, where shoulder, elbow and wrist motion, wrist motion repetition, and external load were used as independent variables. The results showed that only external load had a significant effect on perceived discomfort. The perceived discomfort linearly increased with external load. Based on the results of this and the previous study for males, it was concluded that effect of external load on perceived discomfort was larger than that of other posture and motion repetition related variables. This implies that effect of external load is the most important factor considered in the first place when assessing postural load.

The Effect of Syntactic Complexity on Sentence Repetition Performance and Intelligibility between Specific Language Impairment and Normal Children. (단순언어장애 아동과 정상 아동의 구문적 난이도에 따른 문장따라말하기; 수행력 및 명료도 비교)

  • Ahn, Ji-Sook;Kim, Young-Tae
    • Speech Sciences
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    • v.7 no.3
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    • pp.249-262
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    • 2000
  • The purpose of the present study was to investigate the effect of syntactic complexity (sentence length and sentence structure) on sentence repetition performance and intelligibility between specific language impairment (SLI) and normal children. Thirteen SLI children and twenty-six normal children, matched by 3 years of language, participated in this study. The sentence repetition performance of the subjects were analyzed based on the sentence length (3-word simple sentences and 5-word simple sentences) and sentence structure (5-word simple sentences, 5-word conjoined complex sentences, and 5-word embedded complex sentences). The results of this study indicated the sentence structure influenced sentence repetition performance and intelligibility of SLI children only. The implication of these findings were discussed.

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An Application Based on Smart Device for Special Effect Shooting of Movies

  • Chung, Myoungbeom
    • Journal of the Korea Society of Computer and Information
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    • v.21 no.7
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    • pp.39-46
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    • 2016
  • In this paper, we proposed an application which can conduct to take repetition images for special effect shooting at movies or drama using Bluetooth of smart device. The proposed application can move a camera with motors several times as the same moving after saving of the control data based on the application during specific time using Bluetooth. At the repetition moving, we do not permit to control motors of the camera by person for keeping the same start position and end position after saving the moving data. The camera motors are only moved remotely by saving data of the proposed application. We developed the proposed application and a hardware which works motors with camera to check performance evaluation. Then, we confirmed that the proposed application exactly did the same moving to the motors with camera several times according to saved data. Therefore, because the proposed application can take a same images as control remotely the motors of camera, it will be a useful technology for special effect shooting of movies or dramas.

Effect of Deposition Rate on the Property of ZnO Thin Films Deposited by Pulsed Laser Deposition

  • Kim Jae-Won;Kang Hong-Seong;Lee Sang-Yeol
    • Journal of Electrical Engineering and Technology
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    • v.1 no.1
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    • pp.98-100
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    • 2006
  • ZnO thin films were deposited at different repetition rates of 5 Hz and 10 Hz by pulsed laser deposition. X-ray diffraction (XRD) full widths at half maximum (FWHMs) of (002) ZnO peak in ZnO thin film deposited at 5 Hz and 10 Hz was 0.22 and $0.26^{\circ}$, respectively. The grain size of ZnO thin film deposited at 5 Hz was larger than that of 10 Hz. The variation of repetition rates did not have an effect on the optical property of ZnO thin films. The degradation of the crystalline quality and surface morphology in ZnO thin film deposited at 10 Hz resulted from supersaturation effect by decrease of time interval between a ZnO particle arriving on a substrate by laser shot and a ZnO particle arriving on a substrate by next laser shot.

Evaluation of the Relationship Between Family History of Breast Cancer and Risk Perception and Impacts on Repetition of Mammography

  • Khoshravesh, Sahar;Taymoori, Parvaneh;Roshani, Daem
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.sup3
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    • pp.135-141
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    • 2016
  • Since the mean age of breast cancer in women living in developing countries, compared with those in developed countries, is lower by about 10 years, repetition of mammography can play an important role in reducing morbidity and mortality. Hence, this study aimed to investigate the relationship between family history of breast cancer and risk perception and its impact on repetition of mammography. In this cross-sectional study, 1,507 women aged 50 years and older, referred to the mammography center of Regions 1 and 6 in Tehran, Iran, were enrolled. Data were collected using a self-report questionnaire and analyzed using SPSS and LISREL. According to our findings, knowledge about the time interval of mammography was found to have the highest correlation with repetition of mammography (r=0.4). Among the demographic variables, marital status (${\beta}$= -0.1) and family history of breast cancer (${\beta}$=0.1) had the most direct and significant impact on repetition of mammography (P <0.05). Among the other variables studied, knowledge (${\beta}$=-0.5) had the highest direct and significant impact on repetition of mammography (P <0.05). Family history of breast cancer was one of the predictors of repetition of mammography, but the results did not prove any relationship with risk perception. Further studies are needed to assess the effect of risk perception and knowledge about time interval on the initiation and continuation of mammography.

Development of an Acoustic Velocity Profiler by Using Pulse Repetition Frequency Technique (펄스반복주파수 기법을 이용한 초음파 유속 프로파일러 개발)

  • Lee, Chan-Joo;Kim, Dong-Gu;Lee, Jae-Hoon;Kim, Won
    • Journal of Korea Water Resources Association
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    • v.44 no.9
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    • pp.731-740
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    • 2011
  • An acoustic velocity profiler is developed, which is able to be used for open-channel flow measurement. It measures flow velocity based Doppler effect on acoustic signals, which is estimated by using pulse repetition frequency technique. Laboratory and field tests were made to verify velocity measuring performance of the developed device. It is confirmed that the acoustic velocity profiler can normally measure vertical velocity profile in the range above 0.1 m from the bottom and has equivalent performance to commercial acoustic velocity measuring devices.

A Study on Repeating New Words: Korean Students' Learning and Attitudes

  • Son, Jung-Mi
    • English Language & Literature Teaching
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    • v.16 no.1
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    • pp.143-170
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    • 2009
  • The purpose of this experimental study is to investigate the effects of repeating vocabulary exercises on learning and retaining the meaning, the form, and the use of L2 words. To achieve this purpose, the data from the 87 participants who performed the assigned vocabulary exercises were collected immediately and two weeks later on their learning and retention of the target words. In addition, their attitudes toward the given vocabulary exercises were examined. The results show that the participants repeating exercises showed significantly better results in the immediate posttest, whereas no significant differences were found in the delayed posttest. Consequently, although the repetition effect influence positively on the learning of the target words, these effects are not maintained if they are not reinforced subsequently after the initial introduction to them. Most of the participants in this study identified the importance of repetition in learning new words and also noted that only one encounter with words was not enough for them to acquire the words fully.

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