• Title/Summary/Keyword: dependency test

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A Study on the Springback of High-Strength TRIP Steel (고강도 TRIP 강의 스프링백에 대한 연구)

  • 김용환;김태우;이영선;이정환
    • Transactions of Materials Processing
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    • v.13 no.5
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    • pp.409-414
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    • 2004
  • TRIP steel has got attention in automobile industry because of its high strength and high formability. However, the information on deformation behavior of TRIP steel, including bending and springback, is not enough until now. In this research, the V-die bending experiment and analysis have been done to obtain the information of springback of TRIP steel. And a new numerical method, where elastic modulus is varied with the change of the strain, was suggested. Tensile test for TRIP steel was done to get tensile properties as well as strain dependency of elastic modulus of the material. Strain-dependency of elastic modulus was used the numerical analysis of V-die bending and unbending process to predict springback amount. The results were compared with experiment, showing reasonable agreement. Through the analysis of V-die bending as well as draw bending of TRIP steel, the proposed scheme with variable elastic modulus was proven to well predict the deformation behavior of TRIP steel during bending and springback.

On the Frequency Dependency of Sound Quality Factors (음질 요소의 주파수 의존성에 대하여)

  • 류윤선;최재원;조희복
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 1997.10a
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    • pp.286-292
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    • 1997
  • Sound quality is becoming the major concern in passenger vehicle. The study on it has been done recently but it is not good enough. In order to improve the sound quality in passenger vehicle, so many noise sources must be considered and human feeling to the noise also be taken into account. In this paper, the sound quality was analyzed by vehicle road test which was carried out with varying the traveling speed. As basic factors for sound quality, only objective factors are considered such as loudness, sharpness, speech intelligibility, sound pressure level ... etc. The relations between sound pressure level and other factors are discussed from a point of view of traveling speed dependency. The frequency dependency of sound quality factor is also analyzed by frequency analysis.

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Prediction of Core Promoter Region with Dependency - Reflecting Decomposition Model (의존성 반영 분해모델에 의한 유전자의 핵심 프로모터 영역 예측)

  • 김기봉;박기정;공은배
    • Journal of KIISE:Software and Applications
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    • v.30 no.3_4
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    • pp.379-387
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    • 2003
  • A lot of microbial genome projects have been completed to pour the enormous amount of genomic sequence data. In this context. the problem of identifying promoters in genomic DNA sequences by computational methods has attracted considerable research attention in recent years. In this paper, we propose a new model of prokaryotic core promoter region including the -10 region and transcription initiation site, that is Dependency-Reflecting Decomposition Model (DRDM), which captures the most significant biological dependencies between positions (allowing for non-adjacent as well as adjacent dependencies). DRDM showed a good result of performance test and it will be employed effectively in predicting promoters in long microbial genomic Contigs.

Factors Influencing Nicotine Dependency among College Students Intending to Quit Smoking (금연준비단계 대학생의 니코틴의존도 영향요인)

  • Lee, Hea Shoon;Song, Mi Ryeong
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.20 no.4
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    • pp.429-437
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    • 2013
  • Purpose: The purpose of this study was to identify factors influencing nicotine dependency among college students intending to quit smoking, and to provide data for the construction of programs that will be successful in helping the students quit smoking. Method: In this study a cross-sectional survey to analyze was used. The data were collected between April 22 and April 24, 2013 from 218 college students who had unsuccessfully tried to quit smoking in the past but were now intending to try and quit smoking again. Data were analyzed using frequency, independent t-test, one-way ANOVA and multiple regression with the SPSS 21.0. Results: Factors influencing nicotine dependency were self-efficacy for smoking abstinence (t=-6.60, p=<.001), length of time since beginning to smoke (t=5.39, p<.001), level of carbon monoxide intake (t=2.38, p=.018), and withdrawal symptoms as reasons why the students failed to quit smoking (t=2.22, p=.028). These 4 variables accounted for 35.0% of the variance with regard to nicotine dependency. Conclusions: To conduct a successful program for students who intend to quit smoking, self-efficacy for smoking abstinence, length of time since beginning to smoke, level of carbon monoxide, and withdrawal symptoms as reasons for failing to quit smoking should be considered.

Effects of an Empowerment Program on Nicotine Dependency, Temptation, Self-esteem, Depression in Adolescents Who Smoke (역량강화프로그램이 흡연청소년의 니코틴의존도, 흡연유혹 및 자아존중감, 우울에 미치는 효과)

  • Park, Nam-Hee
    • Child Health Nursing Research
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    • v.18 no.1
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    • pp.1-8
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    • 2012
  • Purpose: The purpose of this study was to identify the effects of an empowerment program on nicotine dependency, temptation, self-esteem, and depression for adolescents who smoke. Methods: The study design was a quasi-experimental study with a nonequivalent control group, pre-post design. The participants were 49 adolescents who smoked. Twenty-six adolescents were assigned to the experimental group and 23 to the control group. The intervention was conducted twice a week for 6 weeks. Chi-square test, t-test, paired-test, Wilcoxon rank sum test and Wilcoxon signed rank test were used to analyze the data. Results: After program, scores for self-esteem (t=5.560, p=.014), were significantly higher and scores for depression (t=-2.111, p=.040) were significantly lower for adolescents in the experimental group compared to adolescents in the control group. Conclusion: The finding indicate that the empowerment group training program was effective in improving self-esteem, and decreasing depression and could be considered as a positive program for smoking cessation for adolescents who smoke.

Rheological Models for Simulations of Concrete Under High-Speed Load (콘크리트 재료의 동적 물성 변화를 모사하기 위한 유변학적(Rheological)모델 개발 및 평가)

  • Hwang, Young Kwang;Lim, Yun Mook
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.35 no.4
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    • pp.769-777
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    • 2015
  • In this study, the rheological models were introduced and developed to reflect rate dependent tensile behaviour of concrete. In general, mechanical properties(e.g. strength, elasticity, and fracture energy) of concrete are increased under high loading rates. The strength of concrete shows high rate dependency among its mechanical properties, and the tensile strength has higher rate dependency than the compressional strength. To simulate the rate dependency of concrete, original spring set of RBSN(Rigid-Body- Spring-Network) model was adjusted with viscous and friction units(e.g. dashpot and Coulomb friction component). Three types of models( 1) visco-elastic, 2) visco-plastic, and 3) visco-elasto- plastic damage models) are considered, and the constitutive relationships for the models are derived. For validation purpose, direct tensile test were simulated, and characteristics of the three different rheological models were compared with experimental stress-strain responses. Simulation result of the developed visco-elasto-plastic damage(VEPD) model demonstrated well describing and fitting with experimental results.

Effects of Smoking Cessation Program for Male University Students: Perceived Nicotine Dependency and Self-efficacy (남자 대학생을 위한 금연프로그램의 효과 - 니코틴 의존도와 자기효능감을 중심으로 -)

  • Chaung, Seung-Kyo;Kim, Chun-Gill
    • Korean Journal of Adult Nursing
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    • v.17 no.2
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    • pp.219-229
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    • 2005
  • Purpose: The purpose of this study was to evaluate the effectiveness of 8 weeks smoking cessation program(SCP) developed by researchers. Method: One group pretest-posttest design was used in this study. The subjects were 88 male university students who consented to participate in the 8 weeks SCP. The SCP in this study consisted of a stop-smoking class, e-mail, SMS(short message service), cellular phone, internet cafe, displayed panel, and patch or acupuncture for quitting smoking. Korean version of questionnaire for nicotine dependency by Ahn et al.(2002), the smoking self-efficacy scale translated by Choi(1999) and subjects' opinion about the SCP were measured. The data were analyzed by using frequency, Chi-Square test, paired t-test and repeated measures ANOVA with SPSS WIN 10.1 Program. Results: 1) The rate of quitting smoking was 31.8% after 8 weeks SCP. 2) There was no significant decrease in the nicotine dependency score among smoking subjects after SCP. 3) There was a significant increase in self-efficacy after SCP. The mean score of self -efficacy in the quitting smoking group increased significantly, but did not significantly change in the smoking group. 4) The stop-smoking class was the most helpful among contents of the SCP. Contents of the SCP except for internet cafe were useful for quitting smoking in this study. Conclusion: The above results indicated that the 8 weeks SCP would be a helpful intervention to quit smoking for male university students.

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Virulence-associated plasmids of Yersinia species isolated from pigs and dogs in Korea (국내 돼지와 개에서 분리된 Yersinia속균의 병독성 관련 plasmid)

  • Choi, Won-pil;Lee, Hun-jun;Jung, Suk-chan
    • Korean Journal of Veterinary Research
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    • v.29 no.2
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    • pp.69-73
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    • 1989
  • Nine strains of Yersinia species isolated from pigs and dogs in Korea, comprising 5 strains of Yersinia enterocolitica, 2 strains of Y kristensenii and each strain of Y pseudotuberculosis and Y intermedia, were examined for the presence of virulence-associated plasmids, calcium dependency and provocation of guinea pig conjuntivitis($Ser{\acute{e}}ny$ test). Three strains of Y enterocolitica isolated from pigs were positive in calcium dependency and harbored one plasmid of about 45 megadalton, but negative in $Ser{\acute{e}}ny$ test.

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Effects of Length and Grade on In-grade Tensile Strength and Stiffness Properties of Radiata Pine Timber

  • Tsehaye, Addis;Buchanan, A.H.;Cha, Jae-Kyung
    • Journal of the Korean Wood Science and Technology
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    • v.26 no.2
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    • pp.16-23
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    • 1998
  • This paper examines the effects of specimen length and grade on the strength and stiffness properties of structural timber of radiata pine. The tensile strength and modulus of elasticity of 1,902 machine-graded boards with 3.15- and 1.62-m clear span lengths, were determined using a horizontal tension test machine. The mean failure and characteristic stress values for tensile strength show an extremely high dependency on test specimen length. The mean and characteristic values of both modulus of elasticity and tensile strength show significant dependency on machine stress grades.

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Dependency on the Forming speed at the warm forming of magnesium sheet (마그네슘 판재 온간 딮드로잉성에서의 속도의존성)

  • Park, H.Y.;Lee, H.S.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2007.10a
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    • pp.246-249
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    • 2007
  • This study is concerned with deep drawability of magnesium sheets(AZ31B) at the warm conditions. Especially the dependency on forming speed has been investigated at the temperature of $200^{\circ}C$ and $300^{\circ}C$. Deep drawing test has been carried out at the temperature of $200^{\circ}C$ and $300^{\circ}C$. The die and blank holder are kept at test temperature by local heating and the punch is kept at room temperature by cooling technique. The magnesium sheets called AZ31B with the thickness of 0.5mm have been applied to deep drawing of circular cup. The drawability has been estimated at the conditions of forming speed (0.1, 1, 10 mm/sec). The results of deep drawing experiments show that the drawability is better at $300^{\circ}C$. Also the deep drawability is improved at the low speed(1mm/sec).

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