• 천문학회지
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• 제26권2호
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• pp.89-98
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• 1993

Magnetostatic models of starspots of late type main sequence stars$(G5V\~K5V)$ have been constructed to investigate their physical characteristics by using the similarity law suggested by Schluter and Temesvary(1958) and later employed by Deinzer(1965) and Yun(1968). The starspots are assumed to be single, circular and in horizontal magnetostatic equilibrium. In the present study we considered only those model spots whose area covers less than $12\%$ of the entire stellar surface as suggested by observations. The computed surface field strength of our model spots ranges from $10^3$\;to\;several\;10^3$ gauss and their magnetic flux is found to be $10\~100$ times that of sunspots. The field strength is sensitive to spectral type, which increases with later spectral type. In contrast to the field strength, the area of starspots depends strongly on the total magnetic flux. Finally, it is noted that the computed field strength of model spots belonging to $G0V\~G5V$ falls below the equipartition field strength at their parent stellar surface unless the coverage is less than $2\%$. This suggests that the observed spot on $G0V\~G5V$ stars is likely to be a group of small starspots.

• 한국세라믹학회지
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• 제32권1호
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• pp.57-62
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• 1995

The coating condition of reproducible anti-reflective coating film and the light transmittance characteristics of the prepared anti-reflective coating glass were investigated as a study for the preparation of single-layer anti-reflective coating glasss. In case of coating with the sol in which the solvent was substituted with the ethanol with the addition of 0.1 mol HNO3, the coated glass showed the minimum value of the refractive index of 1.464, light transmittance of 94.2% at 550nm standard wavelength which is 3.2% higher than that of the parent glass, and the reflectance in the entire wave range of visible light. The refractive index represented its minimum at the sol concentration of 1.0 mol per 100mols of water and the higher the sol concentration, the higher the refractive index, resulting in the decrease of the light transmitance. The production condition of the reproducible anti-reflective coating on glass with the maximum transmittance of 94.2% was 4cm/min of withdrawal speed, 40$0^{\circ}C$ and 1 hour of heat treatment temperature and time, resulting in the film thickness of 94nm.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2006년 제4회 한국유체공학학술대회 논문집
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• pp.383-386
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• 2006

In this study, we propose a new fast algorithm for calculating short range forces in molecular dynamics, This algorithm uses a new hierarchical tree data structure which has a high adaptiveness to the particle distribution. It can divide a parent cell into k daughter cells and the tree structure is independent of the coordinate system and particle distribution. We investigated the characteristics and the performance of the tree structure according to k. For parallel computation, we used orthogonal recursive bisection method for domain decomposition to distribute particles to each processor, and the numerical experiments were performed on a 32-node Linux cluster. We compared the performance of the oct-tree and developed new algorithm according to the particle distributions, problem sizes and the number of processors. The comparison was performed sing tree-independent method and the results are independent of computing platform, parallelization, or programming language. It was found that the new algorithm can reduce computing cost for a large problem which has a short search range compared to the computational domain. But there are only small differences in wall-clock time because the proposed algorithm requires much time to construct tree structure than the oct-tree and he performance gain is small compared to the time for single time step calculation.

• 원예과학기술지
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• 제35권2호
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• pp.149-164
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• 2017

Next generation sequencing (NGS) technologies have led to the rapid accumulation of genome sequences through whole-genome sequencing and re-sequencing of crop species. Genomic resources provide the opportunity for a new revolution in plant breeding by facilitating the dissection of complex traits. Among vegetable crops, reference genomes have been sequenced and assembled for several species in the Solanaceae and Cucurbitaceae families, including tomato, pepper, cucumber, watermelon, and melon. These reference genomes have been leveraged for re-sequencing of diverse germplasm collections to explore genome-wide sequence variations, especially single nucleotide polymorphisms (SNPs). The use of genome-wide SNPs and high-throughput genotyping methods has led to the development of new strategies for dissecting complex quantitative traits, such as genome-wide association study (GWAS). In addition, the use of multi-parent populations, including nested association mapping (NAM) and multiparent advanced generation intercross (MAGIC) populations, has helped increase the accuracy of quantitative trait loci (QTL) detection. Consequently, a number of QTL have been discovered for agronomically important traits, such as disease resistance and fruit traits, with high mapping resolution. The molecular markers for these QTL represent a useful resource for enhancing selection efficiency via marker-assisted selection (MAS) in vegetable breeding programs. In this review, we discuss current genomic resources and marker-trait association analysis to facilitate genome-assisted breeding in vegetable species in the Solanaceae and Cucurbitaceae families.

• 한국작물학회지
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• 제40권5호
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• pp.644-648
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• 1995

연초의 고향품종 육성의 기초결과를 얻기 위하여 향기성분과 관련이 있는 DVTs와 cis-abienol의 유전양상을 조사하였던 바 얻은 결과는 다음과 같다. 1. TLC 방법은 연초 분리집단에서 DVTs와 cis-abienol의 분석 및 이들 성분을 함유한 계통선발에 매우 유용하게 이용될 수 있었다. 2. DVTs와 cis-abienol의 유전양상이 단일우성인자에 의하여 지배되었고 서로 독립적으로 유전을 하였다. 3. DVTs오 cis-abienol의 유전양상이 단일우성인자에 의하여 지배됨으로 연초 고향 품종 육성에 있어서 이들 형질의 도입은 쉬울 것으로 생각된다.

• Journal of Magnetics
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• 제3권4호
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• pp.99-104
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• 1998

The $ Sm_2Fe_{17}N_x $materials were prepared by the combination consisting of the HDDR (hydrogenation, disproportionation, desorption, and recombination) process and nitrogenation or by the conventional way consisting of nitrogenation only, and the magnetic and thermomagnetic properties of the materials were investigated. The magnetic characterisation of the prepared $ Sm_2Fe_{17}N_x $ materials was performed using a VSM. Thermal stability of the materials was evaluated using a DTA under Ar gas atmosphere. The thermomagnetic characteristics of the materials were examined using a Sucksmith-type balance. The previously HDDR-treated Sm2Fe17parent alloy was found to be nitrogenated more easily compared to the ordinary $ Sm_2Fe_{17}N_x $alloy. The $ Sm_2Fe_{17}N_x $ material produced by the combination method showed a high coercivity (12.9 kOe) even in the state of coarse particle size (around 60 ${\mu}{\textrm}{m}$). It was also revealed that the $ Sm_2Fe_{17}N_x $ material produced by the material produced by the combination showed an unusual TMA tracing featured with a low and constant magnetisation at lower temperature range and a peak just before the Curie temperature. This thermomagnetic characteristic was interpreted in terms of the competition between two counteracting effects; the decrease in magnetisation due to the thermal agitation at an elevated temperature and the increase in magnetisation resulting from the rotation of magnetisation of the fine grains comparable to a critical single domain size due to the decreased magnetocrystalline anisotropy at an elevated temperature.

• Child Health Nursing Research
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• 제11권4호
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• pp.444-455
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• 2005

Purpose: This study examined the efficacy of parent training interventions to facilitate social reciprocity and language development in children with autism. Methods: The social interaction behaviors of mothers and children over time were compared using single subject design experimentation methodology. five children who were diagnosed with autism and their mothers participated in the study. The participants were recruited from U city, Korea. The mothers were trained using training videotapes and demonstrations on how to facilitate social interaction with their children as well as promoting language development. following the training, data were collected three times per week by video taping mother-child interaction in their homes. Results: Four of the five mothers demonstrated increases in the use of imitation with animation and expectant waiting after the intervention compared to the baseline sessions; the children demonstrated noticeable increases in the use of initiation of interaction, vocalizations, and verbal production after their mothers received the training intervention. Conclusion : Results of this study demonstrate the efficacy of mother training to improve social interactions of children with autism. Additional important information can be gained by replicating this study with more participants and comparing intervention and control groups. Clearly, this intervention shows promise and has implications far clinical practice.

• 대한안전경영과학회지
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• 제16권2호
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• pp.101-109
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• 2014

This study is about safety education experience and practice of parents who are raising preschool children and the study results are as the following. For safety education experience state, parents had experience of safety education and mostly received it through communities, TV, Internet, etc. The most common educational content was the traffic safety education. For safety education practice degree according to number of children, safety education practice was mostly done well with 1~2 children. For safety education practice degree according to family type, safety education practice degree within the family was done most in nuclear families while healthy life habit safety education practice degree was done most in nuclear families and reconstituted families. Also, for traffic safety education practice degree, it was done well in nuclear families. For respiratory disease safety education practice degree, nuclear families and reconstituted families were the highest and for first aid safety education practice degree, single-parent families were the highest. For safety knowledge level of parents, safety knowledge of family was the highest, followed by safety knowledge of respiratory disease, and traffic. For safety education practice degree and safety knowledge according to safety education experience of parents, there was a significant difference in practice degree according to safety education experience of parents and there was also difference in practice knowledge according to experience. There was also education effect in healthy life habit safety knowledge and traffic safety knowledge.

• Child Health Nursing Research
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• 제16권1호
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• pp.66-72
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• 2010

Purpose: This study was done to identify factors associated with fatigue in pediatric patients with cancer in order to develop nursing interventions for this population. Methods: The participants were 95 pediatric cancer patients admitted to a university medical center in Seoul, Korea, and 95 parents. The $PedsQL^{TM}$, Multidimensional Fatigue Scale developed by Varni (2002) was used to measure fatigue. Data were analyzed with the SAS program and t-test, analysis of variance (ANOVA), Pearson correlation coefficients, and multiple regression were used to identify the association of factors with fatigue. Results: The mean score for fatigue was 30.42 in the pediatric cancer patients and 34.77 in the parents. Fatigue was higher in patients living with a single parent, in patients whose father had a lower education and those patients with a fever. Pain, frequency and intensity of nausea and vomiting, depression, anxiety, and disruption of usual activity were positively associated with fatigue. The predictive factors for fatigue were disruption of usual activity, depression and living with or without parents. Conclusion: Pediatric patients with cancer experienced fatigue during their diagnosis and treatment. Of the multiple factors associated with fatigue, the association between disruption of usual activity and fatigue was the highest indicating a need to be concerned with this factor when providing interventions to alleviate fatigue.

• Bulletin of the Korean Chemical Society
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• 제24권11호
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• pp.1609-1612
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• 2003

The electrooxidation of 8-(3-acetylimino-6-methyl 2,4-dioxopyran)-1-aminonaphthaline (AMDAN) in aqueous and non aqueous media led to the formation of polymeric films, poly (AMDAN). The monomer, undergo anodic oxidation through the formation of a monocation radical irrespective of the nature of the medium. In aqueous medium, the monocation radical undergoes, through its resonance structures, dimerisation involving tail-to-tail, head-to-tail and even head-to-head coupling. The products formed, being more easily oxidisable than the parent substance, undergo further oxidation at the same potential so that the overall oxidation involves a one-step (i.e., a single wave), two-electron process. In non-aqueous medium, the monocation radical does not undergo dimerisation through coupling reactions. Retaining its identity, monomer oxidise in two steps involving one electron in each step. The fact that the cathodic peaks corresponding to these anodic peaks are rarely observed indicates fast consumption of the electrogenerated monocation radicals and dications by follow-up chemical reactions to produce polymeric products (poly AMDAN). The electrochemical behavior of the formed polymer films was investigated in both non aqueous and aqueous media. The films prepared in non aqueous medium were found to be more electroactive than that the films prepared in aqueous medium. This is confirmed with the results in litreature which illustrate that the film prepared in aqueous solution hold water in its structure via hydrogen bonding, which causes decomposition reactions.