• 천문학회지
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• 제42권1호
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• pp.9-15
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• 2009

A necessary condition for the formation of a filament is magnetic helicity. In the present paper we seek the origin of magnetic helicity of intermediate filaments. We observed the formation of a sinistral filament at the boundary of a decaying active region using full-disk $H_{\alpha}$ images obtained from Bi Bear Solar Observatory. We have measured the rate of helicity injection during the formation of the filament using full-disk 96 minute-cadence magnetograms taken by SOHO MDI. As a result we found that 1) no significant helicity was injected around the region (polarity inversion line; PIL) of filament formation and 2) negative helicity was injected in the decaying active region. The negative sign of the injected helicity was opposite to that of the filament helicity. On the other hand, at earlier times when the associated active region emerged and grew, positive helicity was intensively injected. Our results suggest that the magnetic helicity of the intermediate filament may have originated from the helicity accumulated during the period of the growth of its associated active region.

• 천문학회지
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• 제41권6호
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• pp.181-186
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• 2008

Recently, Choe & Cheng (2002) have demonstrated that multiple magnetic flux systems with closed configurations can have more magnetic energy than the corresponding open magnetic fields. In relation to this issue, we have addressed two questions: (1) how much fraction of eruptive solar active regions shows multiple flux system features, and (2) what winding angle could be an eruption threshold. For this investigation, we have taken a sample of 105 front-side halo CMEs, which occurred from 1996 to 2001, and whose source regions were located near the disk center, for which magnetic polarities in SOHO/MDI magnetograms are clearly discernible. Examining their soft X-ray images taken by Yohkoh SXT in pre-eruption stages, we have classified these events into two groups: multiple flux system events and single flux system events. It is found that 74% (78/105) of the sample events show multiple flux system features. Comparing the field configuration of an active region with a numerical model, we have also found that the winding angle of the eruptive flux system is slightly above $1.5{\pi}$.

• Journal of the Korean Wood Science and Technology
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• 제37권2호
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• pp.121-127
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• 2009

Acacia wood (Acacia mangium Willd.) is the most popular fast growing tree species planted in timber estate in Indonesia and is considered to be very valuable raw materials for structural composite products. The objective of the research was to evaluate the properties of OSB prepared from A. Mangium wood with or without immersing the strands to hot water at $80^{\circ}C$ for 2 hours. MDI adhesive was used in 3 levels i.e., 3%, 5%, and 7%. The moisture content of strand was 7%. The results indicated that immersing strands in hot water for 2 hours at $80^{\circ}C$ prior to manufacture OSB improved significantly the mechanical peoperties (i.e., MOR and MOE) of OSB. The higher the adhesive content resulted in the better the dimensional stabilisation (i.e., water absorption and thickness swelling) and the mechanical properties (i.e., MOR, MOE and IB) of OSB. OSB prepared from hot-water immersed strands with 5% adhesive content has met all parameters requirement on the JIS A 5908 (2003) standard.

• 천문학회보
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• 제35권1호
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• pp.29.1-29.1
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• 2010

We report three types of evolutions of EUV bright points (EBPs) which are characterized by their height variations. We analyzed three EBPs during their lifetimes observed by STEREO/SECCHI/EUVI and we obtained heights, sizes, and intensities. Moreover, we investigated their underlying magnetic bipoles observed by SOHO/MDI and we measured distances and fluxes of the two opposite fragments. We found three distinct changes in the heights of the EBPs: upward, downward, and flat. In the upward case, the EBP showed a small and dark structure first, and then changed to a large and bright loop. In the downward case, the EBP first appeared as a large and dark loop structure, and then evolved to a compact and bright loop system. Finally, in the flat case, the height and the size of the EBP didn't change significantly. We found that those EBPs were associated with three distinct contact types of their underlying magnetic fragments, emerging, cancelling, and shearing, respectively. In all cases, both flux emergences and flux cancellations were observed during the lifetimes of the BPs. The flux emergence was dominant in the initial phase and the flux cancellation was significant when the intensity reached its maximum. In addition, we found a remarkable correlation between the heights of the EBPs and the distance of the opposite magnetic fragments.

• 한국ITS학회 논문지
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• 제4권2호
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• pp.45-52
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• 2005

ITS에 대한 사업효과분석은 기존의 전통적인 계획모형을 통해서 산정하기 어려운 문제점을 안고 있다. 이는 전통적인 교통계획 모형이 교통정보와 ITS기술 도입에 따른 영향에 대해 민감하지 못할 뿐만 아니라, ITS기술의 비용, 편익 값에 대한 입력자료가 부재하기 때문이다. Sketch-planning 기법은 전통적인 4단계수요모형을 기반으로 ITS구축에 따른 여행자 패턴 변화를 추정하여 입력 자료로 활용한다. 구축할 ITS시스템의 대안을 수립하고 이때 기본 사례(Do Nothing Case)와 실행사례(Do Case)를 비교하여 이에 대한 비용 편익을 산출하는 과정으로 구성되어 있다. Sketch-planning기법은 입출력 인터페이스, 대안발생 모듈, 편익모듈, 비용모듈, 대안비교 모듈의 5개 모듈로 구성되어 있다. 본 논문에서는 대전광역시 첨단교통모델도시를 사례로 Sketch-planning기법을 이용하여 분석하였다.

• Child Health Nursing Research
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• 제13권2호
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• pp.222-229
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• 2007

Purpose: This study was done to evaluate the validity of the Korean - Child Development Review in screening children with developmental risks. Method: The participants in the study were 172 children aged 6-75 months old and their parents. Data were collected by questionnaire or interview. Korean Denver II and Bayley test were administered with K-CDR for validation of children who were referred for developmental assessment at D University Hospital or public health center. The data were analyzed using correlation, $X^2$ test, and cross tab analysis. Results: There was a significant relationship between the K-CDR and Korean Denver II. The correlation coefficients were .42 to .61 by developmental sector. The sensitivity and specificity of K- CDR were .84 and .66 respectively when "abnormal" with MDI of Bayley test defined as lower than 85 the score which was used as a diagnosis of developmental delay. The responses to 6 questions for parents showed significant differences according to 3 groups by developmental state. Parents of children in the developmental disability group more frequently checked problems from the 26 problem checklist about their children's development and behavior. Conclusion: The results show that K-CDR is valid and has good sensitivity and moderate specificity in screening developmental delay.

• 한국간호교육학회지
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• 제16권1호
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• pp.111-120
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• 2010

Purpose: The purpose of this study was to evaluate the correct use of inhalers and to examine the patients characteristics affecting correct use of inhalers in patients with obstructive pulmonary disease. Method: Subjects were 280 patients with obstructive pulmonary disease who visited the internal pulmonary outpatient departments in 2 university hospitals in Korea. Inhaler use of each patient was assessed using a checklist recommended by the National Asthma Education and Prevention Program Expert Panel. Result: Most subjects used a DPI or MDI. The overall mean score of correct use was 72.09. Most subjects responded they knew well how to use their inhalers. Most frequent error was 'not fully exhaling before inhalation'. A younger age, higher educational level, living with family, and awareness of inhaler use were significantly associated with correct use of inhalers. Conclusion: The findings of this study showed that most of patients were unable to use inhalers correctly even though they had prior educational experiences. Regular assessing of inhaler use and adequate inhaler education considering patients characteristics by nurses are needed.

• 대한가정학회지
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• 제44권2호
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• pp.103-112
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• 2006

This study followed the standardization study pool of K-BSID-II to examine the stability of K-BSID-II. One hundred and ninety five infants aged from 1-42 months tested twice with intervals of 5-16 month between tests. All participants had been full-term babies without any medical complications. There were no significant differences between the groups which were divided in terms of demographic variables such as mothers' education, infants' birth order and gender. The stability of K-BSID-II was significant and that of the mental scale was lower than that of the psycho-motor scale: There were high stabilities between raw scores in two sessions(r=.91 for the mental scale and r=.89 for the psycho-motor scale) but there were significant but low correlations between mental index scores(r=.18, p<.05) and psycho-motor index scores(r=.17, p<.05). The stability was increased with initial test age and mothers' education. It was recommended for testers and researchers to use both raw scores and index scores for better interpretations in future research.

• Macromolecular Research
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• 제13권3호
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• pp.212-217
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• 2005

The pyrolysis kinetics of polyurethanes synthesized from polycaprolactone diol (PCL) and diisocyanate (HDI, $H_{12}MDI$) using catalysts such as dibutyltin dilaurate (DBTDL) were studied by a thermogravimetric (TG) technique, which involved heating the sample at the rates of 10, 20 and $30^{\circ}C$/min. The effect of the kind of diisocyanate and the hard segment contents on the activation energy and reaction order were examined at conversions ranging from 1 to $100\%$. The activation energies at first increased slowly with increasing conversion. Also, differential scanning calorimetry (DSC) was used to investigate the structural differences in each polyurethane. DSC can reveal the melting behavior, in terms of the glass transition temperature ($T_g$), which is known to vary as a function of the stoichiometry and processing conditions.

• 한국산업보건학회지
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• 제9권2호
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• pp.1-18
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• 1999

The purpose of this study was to compare performances of two analytical methods, the OSHA 42 and the NIOSH 5522, of quantifying total isocyanates in air. These methods were compared in terms of accuracy and precision and the detection limits using four(4) spiked samples in each of four(4) concentration levels which ranged from 0.25 to 2.0 times of the ACGIH TLV-TWA. In addition, two methods were used to as sess airborne concentrations of total isocyanates at the following processes including autobody spray painting, furniture spray painting, polyurethane foaming, urethane adhesion, UV coating, and pigment mixing. The results of this study showed that the NIOSH 5522 method was better than the OSHA 42 method in terms of accuracy, precis ion, and detection limit for quantifying airborne total isocyanates. It was also clear that the NIOSH method was capable of detecting not only monomeric but also non-monomeric isocyanates. The results of air concentrations of total isocyanates among processes studied indicate that some processes may exceed the recommended level of isocyanates. In addition, to evaluate toxicological effects of total isocyanates, it is recommended to consider additive effects of isocyanates present in mixtures.