• Human Ecology Research
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• 제60권1호
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• pp.53-68
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• 2022

Using a person-centered approach, the current study investigated latent profiles for the emotional and behavioral problems of students in sixth-grade in elementary school and second grade of middle school. The aim was to explore latent transition patterns and verify the factors affecting the transitions. The participants were 1,937 adolescents who responded to the 3^rd year (6^th grade of elementary school; Time 1), 4^th year (1^st grade of middle school), and 5^th year (2^nd grade of middle school; Time 2) of the Korean Children Youth Panel Study. Latent profile and latent transition analyses were performed. The results were as follows: first, the latent profile of emotional and behavioral problems changed from Time 1 to Time 2. The latent groups at Time 1 were classified into low, moderate, high, and externalizing-dominant, whereas at Time 2, five groups were identified: low, moderate, high, externalizing-dominant, and withdrawal-dominant. Second, transition analyses revealed that although 22.3-57.0% of latent groups remained unchanged, there were significant changes over time between groups, as a new group ('withdrawal-dominant') emerged in Time 2. Third, different factors influenced the latent profile transition of emotional and behavioral problems depending on the transition pattern. Higher levels of self-esteem, better relationships with peers and teachers, and lower levels of parental inconsistency meant emotional and behavioral problems had not worsened at Time 2. The results suggest that early interventions are needed during the transition from childhood to early adolescence.

• 유변학
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• 제2권1호
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• pp.79-86
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• 1990

상업적으로 많이 이용되는 불포화 폴리에스터

• 한국동물학회:뉴스레터
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• 제12권2호
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• pp.107.2-107
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• 1995

No Abstract, See Full Text

• 타이어
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• 통권143호
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• pp.33-37
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• 1989

이 자료는 미국의 타이어 전문지인 「Modern Tire Dealer」에서 조사한 것으로, 딜러들이 진단한 '89년도 미국의 트럭 타이어시장에 대한 전망이다. 여기에서 Low Profile Tire는 L/P로, Conventional Tire는 Con.으로 표기한다.

• 한국동물학회:학술대회논문집
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• 한국동물학회 1995년도 한국생물과학협회 학술발표대회
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• pp.243.2-243
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• 1995

No Abstract, See Full Text

• Archives of Pharmacal Research
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• 제7권1호
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• pp.23-31
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• 1984

An improved mass spectrometric method for multicomponent analysis of metabolites in urine, well-suited for clinical biochemistry, is described. The method involves solvent elution of the metabolites from an adsorbent and the concentration of the eluate on a microadsorption column. This is administered by a direct inlet probe into the ionizing source of field ionization mass spectrometry (FIMS), which yield a molecular weight profile of the metabolites. The procedure provides rapidly (within one hour) reproducible profiles from a small volume of urine. The optimization of the sampling technique and the reproducibility are discussed.

• 한국전기전자재료학회논문지
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• 제18권10호
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• pp.883-890
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• 2005

In this paper, the established model of NBTI (Negative Bias Temperature Instability) mechanism was reviewed. Based on this mechanism, then, the influence of nitrogen was discussed among other processes. A constant concentration of nitrogen exists inside $SiO_2$ in order to prevent boron from diffusing and to increase dielectric constant. It was shown that NBTI improvement was achieved by controlling nitrogen profile. It was supposed that the existence of low activation energy of Si-N bonds at $Si-SiO_2$ interface attributes the improvement by making hydrogen prevent interface traps. It was also shown that improvement of NBTI can be achieved by more effective control of nitrogen profile. It was supposed that the maximum control of nitrogen profile can be achieved by DPN (Decoupled Plasma Nitridation) process.

• 한국공작기계학회논문집
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• 제16권5호
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• pp.129-133
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• 2007

Focused Ion Beam(FIB) systems is a useful tool for the fabrication of micro-nano scale structures. In this study, the effects of FIB etching on the Au microstructure are systematically investigated. As the fabrication parameters, ion dose, dwell time and beam overlap ratio are studied. First, the increases of Ga ion dose makes the milling yield higher and the sidewall of milling profile steeper. Dwell time is found to have little effects on the milling profile due to the relatively large milling area of $1\times1{\mu}m^2$ used in this study. However, beam overlap significantly affects not only milling rate but also milling profile. As the beam overlap ratio changes from positive to negative, the development of regular cross-stripe patterns at the bottom with low milling rate is observed.

• International Journal of Automotive Technology
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• 제5권1호
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• pp.23-31
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• 2004

Secondary movements of piston in the bore clearance are closely related to the side impact to the engine block as well as many tribological problems. Some of the major parameters that influence these kinds of movements are piston profile shapes (barrel and flat), piston pin offsets and the magnitudes of bore clearances. In our study, computational investigations are performed about the piston movements in the bore clearance by changing the skirt profiles and piston offsets. In this work, it is found that curved profile and larger offset magnitude to thrust side provide better performance that has low side impact during the engine cycle.

• 한국자동차공학회논문집
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• 제6권4호
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• pp.39-46
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• 1998

For permanent magnet brushless DC motors used for high speed fuel pumps, torque ripple is an important origin of vibration, acoustic noise and speed fluctuation. In this paper, the output torque profile of a PM motor with one phase energized is decomposed into the commutation torque, the reluctance torque and the armature reaction torque according to their source origins. It verifies that the output torque profile is qualitatively equivalent to the BEMF profile for low reluctance motors. This paper discusses the effect of magnet pole shaping and magnet arc length on the output torque and torque ripple. A magnet edge shaping is proposed to design a trapezoidal BEMF motor without torque ripple, with minimal sacrifice of the maximum output torque.