• Title/Summary/Keyword: Correct ratio

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Physical Properties of Polyester, Tencel and Cotton MVS Blended Yarns with Yarn counts and Blend Ratio (PET, Tencel, Cotton MVS 혼방사의 섬도와 혼용률에 따른 물성 특성)

  • Sa, A-Na;Lee, Jung Soon
    • Fashion & Textile Research Journal
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    • v.17 no.2
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    • pp.287-294
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    • 2015
  • This study investigates the physical properties of Murata Vortex Spinning (MVS) blended yarn with yarn count(20's, 30's, 40's) and blend ratio(Polyester 100, Polyester70:Cotton30, Polyester50:Cotton50, Polyester30:Cotton70, and Polyester50:Tencel40:Cotton10). This study evaluated tenacity, elongation, bending rigidity, bending hysteresis, hairiness coefficient, irregularity and twist number. The structure of MVS blended yarn influenced stress, strain, bending rigidity, bending hysteresis and the hairiness coefficient of MVS blended yarn decreased as the yarn count increased. MVS blended yarn consists of core and sheath. The core of MVS blended yarn is composed of a parallel fiber with a wrapping fiber that covers thecore fiber. This special structure of the MVS blended yarn effects the physical properties of the yarn; in addition, the mechanical properties of the component fibers influenced the stress, strain, bending rigidity, bending hysteresis and hairiness coefficient of MVS blended yarn with the blend ratio. Polyester decreases and cotton increases resulted in decreased physical properties. A similar polyester content increased the tencel and physical properties. Appropriate physical properties and a variety of touch expression can be realized through a correct blend ratio.

The Effect of Nutrition Education based on Theory of Multiple Intelligence in Elementary School Students (다중지능이론에 기초한 학습지도안이 일부 초등학생의 영양교육에 미치는 효과)

  • Lee, In-Yi;Lee, Je-Hyuk;Kim, Myung-Hee
    • The Korean Journal of Food And Nutrition
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    • v.28 no.1
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    • pp.134-142
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    • 2015
  • The purpose of this study was to identify the effects of nutrition education on elementary school students based on the theory of multiplex intelligence. Of the 56 elementary school students that participated in this survey, 37 (66.0%) had no siblings. The number of students whose mothers had jobs and those whose mothers did not work were 37 (67.9%) and 18 (32.1%), respectively. Food consumption with ordinary diets was normal in 23 students (41.1%) and the average frequency of snack intake and eating-out was determined to be twice a day (41 students, 73.2%) and once or twice per week (36 students, 64.3%), respectively. The most popular type of food consumed when eating-out was 'fast foods' in 28 students (50.0%). It was determined that on average, 39 students (69.6%) snacked between lunch and dinner time and 31 (55.4%) selected snacks based on information obtained through 'mass media'. Analysis of the effects of nutrition education revealed an increase in the number of correct answers to the question 'foods with high nutritional value are high calorie foods,' with significant difference, but not in other questionnaires. In addition, the correct information for calcium (p<.05), good dietary habits (p<.001), food poisoning (p<.05), and six groups of nutrients in foods (p<.001) improved after nutrition education, with significant differences. As a result, the ratio of correct answers increased after nutrition education, with a significant difference (p<.001). After the education, the experimental group had a higher total score than the control group, with significant difference (p<.01).

Influences of Tobacco-Related Knowledge on Awareness and Behavior towards Smoking

  • Park, Jinju;Lim, Min Kyung;Yun, E Hwa;Oh, Jin-Kyoung;Jeong, Bo Yoon;Cheon, Yejin;Lim, Sujin
    • Journal of Korean Medical Science
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    • v.33 no.47
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    • pp.302.1-303.10
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    • 2018
  • Background: A considerable amount of research has shown that knowledge and appropriate awareness are essential for encouraging positive behaviors and promoting health. In Korea, the roles that behavioral changes play in the prevention of cancer have been an important issue since the introduction of the 10 codes for cancer prevention in 2006. Thus, the present study investigated the associations of tobacco-related knowledge with awareness and attitudes towards positive smoking-cessation behaviors. Methods: The present study analyzed data from the 2010 national questionnaire survey (n = 1,006). This study evaluated sociodemographic characteristics, smoking status, self-rated health status, health-related interests, and the accuracy of 12 tobacco-related statements to determine knowledge level and to investigate its impact on awareness and behaviors related to smoking. These parameters were examined and staged using the Precaution Adoption Process Model. Results: A higher level of tobacco-related knowledge was significantly associated with a positive attitude towards smoking cessation (5-8 correct answers: odds ratio [OR], 2.53; 95% confidence interval [CI], 1.57-4.08; ${\geq}9$ correct answers: OR, 3.90; 95% CI, 2.22-6.82; reference: ${\leq}4$ correct answers). Interestingly, among current smokers, only those who correctly responded to ${\geq}9$ of 12 tobacco-related statements were significantly associated with a positive attitude towards smoking cessation. Conclusion: This study found that having a higher level of tobacco-related knowledge had a significant impact on positive attitudes towards smoking cessation. This suggests that there is a need to disseminate appropriate knowledge to the general population to encourage positive attitudes and promote healthful behaviors in terms of smoking.

Prevalence Rate and Factors of Myopia in Preschool Children (서울시 학령전기 아동의 근시 유병률과 관련요인)

  • Kim Shin-Ja
    • Journal of Korean Academy of Nursing
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    • v.35 no.2
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    • pp.390-398
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    • 2005
  • Purpose: This study was aimed at providing basic data for developing a nursing intervention program which enables systematic and correct visual acuity care by discovering out visual acuity conditions, prevalence rate of myopia, and the factors related to myopia with Preschool children. Method: The subjects of this study consisted of 519 children between 3 and 6 years of age from 12 kindergartens in Seoul which were selected through multiple cluster sampling. Myopia was defined as the spherical equivalent (SE) of more than -0.5 diopters (D) in the right eye. The data was analyzed by t-test, 2-test, ANOVA, and logistic regression by using the SAS program. Result: The prevalence rate of myopia was $8.7\%$. the odds ratio of child myopia when one parent had myopia was 2.2 times higher than when neither parent had myopia. The odds ratio of child myopia when reading more than three books per week was 0.27 times higher than reading less than three books. Conclusion: Myopia should be continuously and intensively managed from the age of 3.

Analysis of Flux Observers Using Parameter Sensitivity

  • Nam H.T.;Lee K.J.;Choi J.W.;Kim H.G.;Chun T.W.;Noh E.C.
    • Proceedings of the KIPE Conference
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    • 2001.10a
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    • pp.418-422
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    • 2001
  • To achieve a high performance in direct vector control of induction motor, it is essential to correct estimation of rotor flux. The accuracy of flux observers for induction machines inherently depends on parameter sensitivity. This paper presents an analysis method for conventional flux observers using Parameter Sensitivity. The Parameter sensitivity is defined as the ratio of the percentage change in the system transfer function to the percentage change of the parameter variation. We define the ratio between real flux and estimated flux as the transfer function, and analyzed a parameter sensitivity of this transfer function by simulation.

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Analysis of Induction Machine Flux Observer (유도전동기 자속추정기의 특성해석)

  • Nam Hyun-Taek;Lee Kyung-Joo;Choi Jong-Woo;Kim Heung-Geun
    • Proceedings of the KIPE Conference
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    • 2001.12a
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    • pp.7-10
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    • 2001
  • To obtain a high performance in a direct vector controlled induction machine, it is essential to correct estimation of rotor flux. The accuracy of flux observers for induction machines inherently depends on parameter sensitivity. This paper presents an analysis method for conventional flux observers using Parameter Sensitivity. The Parameter sensitivity is defined as the ratio of the percentage change in the system transfer function to the percentage change of the parameter variation. We define the ratio between real flux and estimated flux as the transfer function, and analyzed a parameter sensitivity of this transfer function.

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Power Efficient Modulation Scheme $CDM^2-MAP$ for Low Complexity and High Performance

  • Khuong Ho Van;Kong Hyung-Yun;Nam Doo-Hee
    • Journal of Communications and Networks
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    • v.8 no.1
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    • pp.1-7
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    • 2006
  • Quadrature amplitude modulation-spread spectrum (QAM-SS) and code division multiplexing (CDM) are multi-level modulation schemes with high performance but they cause a large peak-average power ratio (PAPR). Therefore, this paper proposes a novel modulation scheme for high-rate transmission which follows a sequence of CDM-mapping-CDM not only to correct the above-mentioned problem but also offer a high flexibility in obtaining arbitrary multilevel modulation with very low implementation complexity and high performance.

Analysis of Induction Motor Flux Observer using Parameter Sensitivity (파라메터 민감도를 이용한 유도전동기 자속 추정기 해석)

  • Nam, Hyun-Taek;Lee, Kyung-Joo;Kim, Jin-Kyu;Choi, Young-Tae;Choi, Jong-Woo;Kim, Heung-Geun
    • Proceedings of the KIEE Conference
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    • 2001.07b
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    • pp.1176-1178
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    • 2001
  • To obtain a high performance in a direct vector controlled induction machine, it is essential to correct estimation of rotor flux. The accuracy of flux observers for induction machines inherently depends on parameter sensitivity. This paper presents an analysis method for conventional flux observers using parameter Sensitivity. The Parameter sensitivity is defined as the ratio of the percentage change in the system transfer function to the percentage change of the parameter variation. We define the ratio between real flux and estimated flux as the transfer function, and analyzed a parameter sensitivity of this transfer function.

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Simplified approach for the evaluation of critical stresses in concrete pavement

  • Vishwakarma, Rameshwar J.;Ingle, Ramakant K.
    • Structural Engineering and Mechanics
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    • v.61 no.3
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    • pp.389-396
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    • 2017
  • Concrete pavements are subjected to traffic and environmental loadings. Repetitive type of such loading cause fatigue distress which leads to failure by forming cracks in pavement. Fatigue life of concrete pavement is calculated from the stress ratio (i.e. the ratio of applied flexural stress to the flexural strength of concrete). For the correct estimation of fatigue life, it is necessary to determine the maximum flexural tensile stress developed for practical loading conditions. Portland cement association PCA (1984) and Indian road congress IRC 58 (2015) has given charts and tables to determine maximum edge stresses for particular loading and subgrade conditions. It is difficult to determine maximum stresses for intermediate loading and subgrade conditions. The main purpose of this study is to simplify the analysis of rigid pavement without compromising the accuracy. Equations proposed for determination of maximum flexural tensile stress of pavement are verified by finite element analysis.

Analysis and Improvement of Low-Frequency Control of Speed-Sensorless AC Drive Fed by Three-Level Inverter

  • Chang Jie (Jay)
    • KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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    • v.5B no.4
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    • pp.358-365
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    • 2005
  • In induction machine drive without a speed sensor, the estimation of the motor flux and speed often becomes deteriorated at low speeds with low back EMF. Our analysis shows that, in addition to the state resistance variation, the estimated value of field orientation angle is often corrupted by accumulative errors from the integration of voltage variables at motor terminals that have low signal/noise ratio at low frequencies. A repetitive loop path of integration in the feedback can amplify this type of error, thus speeding up the degradation process. The control system runs into information starvation due to the loss of correct field orientation. The machine's spiral vectors are controlled only in a reduced dimension in this situation. A novel control scheme is developed to improve the control performance of motor's current, torque and speed at low frequencies. The scheme gains a full-dimensional vector control and is less sensitive to the combined effect of the error sources at the low frequencies. Experimental tests demonstrate promising performances are achievable even below 0.5 Hz.