• Proceedings of the KWS Conference
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• 2009.11a
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• pp.76-76
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• 2009

눈부신 전자산업의 발달로 대부분의 전자제품이 다기능/경박단소화 되고 있어, 고밀도 실장 기술인 양면 표면실장과 고집적 패키징 기술인 패키지 적층 공정의 적용이 점차 확대되고 있다. 따라서 양면 표면실장 및 패키지 적층 공정에 사용되는 저온 접합용 무연 솔더 즉, $183^{\circ}C$(Sn-37Pb 공정 솔더 융점) 이하의 융점을 가지는 저온 무연 솔더에 대한 관심이 높아지고 있다. 한편, 미세피치 적용 분야에 있어 ACF/P를 이용한 COG 접속 분야 외에도 최근 저온 접합용 무연 솔더를 이용한 접속 분야가 각광을 받고 있다. 따라서, 접속피치 미세화에 대응하기 위해 스크린 인쇄성을 향상시킬 수 있는 저온 무연 솔더 paste 제조 및 공정 기술의 개발이 필요한 실정이다. 현재 대표적인 저온 무연 솔더 조성은 Sn-Bi계($138^{\circ}C$ 융점)와 Sn-In계($120^{\circ}C$ 융점)이다. 하지만, 이들 조성의 신뢰성 등에 있어 개선의 여지가 있으므로 이를 해결하기 위한 무연솔더 조성의 개발이 필요하다. 이와 같은 관점에서, 본 연구는 $137^{\circ}C$의 융점을 갖는 Sn-57.6Ag-0.4Ag 저온 무연 솔더 paste를 $217^{\circ}C$의 융점을 갖는 Sn-3.0Ag-0.5Cu 솔더 paste와 비교하여 인쇄성, reflow 특성, void inspection, 미세조직 관찰 및 underfill 적용 등의 실험을 실시하였다.

• Korean Journal of Veterinary Research
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• v.33 no.3
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• pp.465-469
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• 1993

This paper dealt with the histopathological findings on the natural cysticercosis in pigs. Three cases of porcine cysticercosis, which had been kept in the Department of Veterinary Medicine, Cheju. University more than ten years, were histopathologically examined in order to see the host reaction to the parasite. Capsules containing scolex were mainly found in the fascia of skeletal muscle, heart, and brains. Microscopically, cysticerci in the epicardium and the fascia of skeletal muscles were encapsulated with fibroblasts and collagen fibers. Around capsules, there was infiltration of eosinophils, lymphocytes and macrophages, although the degree and severity of inflammatory reaction varied case by case. Cerebral cortex also had the inflammatory exudate of lymphoid cells in the vicinity of the scolex. whereas perivascular lymphocytic cuffings were commonly seen around capsules. GFAP immunoreactive fibers formed a limiting membrane along the outer side of capsules. There was also proliferation of GFAP-positive astrocytes encirling infiltrating lymphocytes around vessels. In the central nervous system, astrocytes and lympoid cells play an important role in the demarcation of cysts and local immunity, respectively. In conclusion, host tissue reaction in porcine cysticercosis seemed to vary significantly according to the affected organs of pigs. It is assumed that capsules containing worms seemed to be formed at early stage of cysticercosis.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.26 no.1
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• pp.30-37
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• 2015

Objectives: The purpose of this study was to verify the validity and clinical cutoff score of the Child Behavior Checklist for ages 1.5-5 (CBCL 1.5-5) for diagnosis of autism spectrum disorder (ASD). Methods: 44 ASD infants and 100 normal infants participated. T-test, discriminant analysis, receiver operating characteristic (ROC) curve analysis, and odds ratio analysis were performed on the data. Results: Discriminant validity was confirmed by mean differences and discriminant analysis on the subscales of Withdrawn, Attention problems, Internalizing problems, Externalizing problems, Total problems, and all Diagnostic and Statistical Manual of Mental Disorders (DSM)-oriented scales between the two groups. ROC curve analysis showed that Withdrawn, Attention problems, Internalizing problems, Externalizing problems, Total problems, DSM pervasive developmental problems, DSM attention deficit/hyperactivity problems, and DSM oppositional defiant problems significantly predicted ASD infants compared to normal infants. In addition, the clinical cutoff score criteria adopted in the Korean CBCL 1.5-5 for subscales of Withdrawn, Attention problems, Internalizing problems, Externalizing problems, Total problems, DSM pervasive developmental problems, DSM attention deficit/hyperactivity problems, and DSM oppositional defiant problems were shown to be valid. Conclusion: The subscales of Withdrawn, Attention problems, Internalizing problems, Externalizing problems, Total problems, DSM pervasive developmental problems, DSM attention deficit/hyperactivity problems, and DSM oppositional defiant problems significantly discriminated for the diagnosis of ASD.

• Korean Journal of Childcare and Education
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• v.10 no.2
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• pp.295-317
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• 2014

This study is intended to improve parental capacity from the viewpoint of children's happiness. It extracts a core parental capacity for children's happiness from the international index such as OECD well-being, UNICEF Children's welfare, International survey of children's well-being, and Korean children's key index. Based on the extracted core parental capacity, this study developed a self-checklist aiming to perceive parents' capacity status and suggest a political plan in order to improve parents' capacity for children's happiness. The self-checklist has a total of 66 questions and is composed of 7 domains; Child development, Health and Safety, Family relation, Physical and material environment, Play, Guidance in life, and Community engagement. The results from the survey are as follows. The domains of Development of children as well as Health & Safety are reported as the highest value at 4.1 point; on the contrary, those of Guidance in life and Community engagement are reported as the lowest value at 3.8 point. In terms of age, it was reported that the capacity of parents under 35 years-old was better than that of parents over 35 years of age. As for family income, it was revealed that the order of parents' capacity generally depends on the family income.

• Korean Journal of Community Nutrition
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• v.9 no.5
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• pp.555-565
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• 2004

The objective of this study was conducted to investigate growth and development status of infants fed soy-based formulas over 3 months. The height and weight were measured and Z-scores were calculated by using standard of the same age groups. Their mothers were interviewed using questionnaires including general and environmental characteristics, total food intakes, soy based formula intakes and Ewha infant development screening test. Main results were as follows: 1) Nutrient intake levels of subjects were similar to or more than the level of Korean Recommended Dietary Allowances except for intakes of vitamin E (79.89% RDA), and the average status of nutrient intakes of infants were fairly good. 2) Z-scores of height for age (HAZ) and Z-scores of weight for age (WAZ), Kaup index, WLI and Ewha Infant Developmental Screening Test score of subjects were in the normal growth range. 3) There were no significant differences among soy based formula intake percentile groups in HAZ, WAZ, Kaup index, WLI and Ewha Infant Developmental Screening Test score. 4) Total energy intake was positively correlated with HAZ (p < 0.00, WAZ (p <0.00, and WLI (p < 0.05) in infants less than 12 month. Also, soy based formula energy intake was positively correlated with HAZ (p < 0.05) in infants less than 12 month. However, energy and soy based formula intake levels of infants over 12 month were not significant among variables. Considering results of this study, infants fed soy-based formulas over 3 months showed normal growth and development status. Further studies are needed to evaluate longterm growth and development in infants fed soy based formulas.

• Human Ecology Research
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• v.55 no.2
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• pp.125-140
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• 2017

This study composed spatial cognition tasks within the system of geometric area to study children's spatial cognition development systematically. It surveyed children's execution of direction, rotation, symmetry, conjugation, and part/whole cognition tasks. A spatial geometry cognition task set (consisting of total 27 sub-tasks) was presented to 60 children (20 each in groups of 3-, 4-, and 5-year-old) in order to confirm how children's execution of spatial geometry cognition changed depending on children's age and sex as well as if the execution of the spatial geometry cognition showed a difference after each task area. As a result, the execution of the whole direction task and the part/whole task gradually increased between age 3 and age 5. The execution of the whole rotation task, whole symmetry task, and whole conjugation task rapidly increased between age 3 and age 4. Significant sexual difference did not appear in the execution of spatial geometry cognition tasks. The execution of the conjugation and part/whole task was high in each task area, and the execution of the direction, rotation, and symmetry task was relatively low. In addition, the difference of task execution appeared in the sub-tasks of direction, symmetry, and conjugation areas. This result suggests the theoretical discussion possibility of children's spatial geometry cognition development. In addition, the empirical results of this study can be applied to child education plans and activity compositions appropriate for child development.

• The Journal of the Korea Contents Association
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• v.21 no.4
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• pp.603-614
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• 2021

The purpose of this study is to explore whether reading picturebooks portraying children's play assists adult readers to recall their childhood play memories according to the narrative model of human development. In this study, adult readers recalled their play memories before and after reading a picturebook depicting children's play. Adult readers' responses to the picturebooks were also collected. The types of play from their memories were categorized and the responses were qualitatively analyzed through open coding. The results indicated that first, before reading picturebooks portraying children's play, the type of play that adult readers mostly recalled was games with rules which happened outdoor. Second, after reading a picturebook, adult readers recalled new play memories which contained more detailed elements of narratives. Third, most adult readers responded to picturebooks either emotionally or aesthetically. This study suggests the perspective on picturebooks as a literature and art genre for readers from birth to death. In addition, as an evocative object, a picturebooks could assist adult readers to recall and rediscover their childhood.

• Pediatric Infection and Vaccine
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• v.30 no.2
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• pp.91-96
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• 2023

Infection with enterovirus (EV) 71 is usually associated with hand-foot-and-mouth disease and herpangina. The most frequent neurologic complication is brainstem encephalitis. A 30-month-old boy visited the pediatric emergency department with fever, lethargy, and abnormal eye contact. His mental status was slightly drowsy. On hospitalization day 2, the patient experienced respiratory arrest with apnea. Brain magnetic resonance imaging revealed bilateral symmetric T2-high signal lesions without enhancement in the posterior aspect of the brainstem and left medial temporal lobe. Electroencephalography was indicative of diffuse cerebral dysfunction with diffuse high amplitude and irregular delta activities. He underwent a gene study and was diagnosed with myoclonic epilepsy with ragged red fibers syndrome. We report a case of EV 71 brainstem encephalitis by polymerase chain reaction for nasopharyngeal aspirates and feces with rapid progression within one day of fever without the manifestation of throat and skin lesions because of his underlying mitochondrial disease.

• Journal of Nutrition and Health
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• v.51 no.3
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• pp.242-253
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• 2018

Purpose: The purpose of the study was to identify the nutrition knowledge, dietary attitudes of guardians, and nutritional status of infants and toddlers as well as the relationships between these variables. Methods: The participants were selected among applicants for low-income family financing provided by the government and included 115 infants and toddlers as well as their guardians. Demographic data, nutrition knowledge, dietary attitudes, and nutrition intakes were assessed using a self-administered questionnaire, biochemical examination, and 24 Hour-Recall method. Results: The score for guardians' nutrition knowledge was 12.97 points of a possible 15, and the score for dietary attitudes was 53.38 points of a possible 75. The nutrition knowledge and dietary attitudes showed significant differences by education level (p < 0.05) and family structure (p < 0.05). Energy intakes of subjects aged 6 ~ 24 months and over 25 months were lower than the DRI for Koreans. The intakes of carbohydrates, protein, and fat of subjects aged 6 ~ 24 months and over 25 months showed no significant differences by level of nutrition knowledge or dietary attitudes. The intake of Ca of subjects aged over 12 months showed significant differences by level of nutrition knowledge (p < 0.05). The intakes of Thiamin of subjects aged 6 ~ 11 months and P of subjects aged over 12 months showed significant differences by level of dietary attitudes (p < 0.05). There was a small positive correlation between education level and nutrition knowledge as well as between dietary attitudes. Nutrition knowledge showed a positive correlation with dietary attitudes. There was a positive correlation between nutrition knowledge and Ca, Riboflavin, as well as Vit C levels. Conclusion: Therefore, it is necessary to consider an educational program for increasing the practical application of knowledge to nutrition management for improvement of nutrition intake in infants and toddlers.

• Clinical and Experimental Pediatrics
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• v.48 no.3
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• pp.298-305
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• 2005

Purpose : We performed this study to evaluate the mean serum levels of insulin-like growth factor (IGF)-I, insulin-like growth factor binding protein(IGFBP)-2 and IGFBP-3 in healthy Korean children according to age and sex. Methods : Ninety two healthy children, consisting of 42 boys and 50 girls, were classified into five groups according to age : neonate; infancy; early childhood; late childhood; and adolescence. We measured serum levels of IGF-I, IGFBP-2 and IGFBP-3 by enzyme-linked immunosorbent assay(ELISA) and analysed the serum levels according to sex and age group. Results : For boys, the mean serum levels of IGF-I(ng/mL) in neonate, infancy, early childhood, late childhood and adolescence were $41.1{\pm}3.6$, $70.9{\pm}33.7$, $103.5{\pm}97.2$, $89.8{\pm}46.5$ and $51.4{\pm}27.8$, respectively. Those of IGFBP-2(ng/mL) were $8.2{\pm}3.4$, $5.8{\pm}0.4$, $9.3{\pm}4.0$, $9.5{\pm}1.1$ and $7.0{\pm}0.5$, respectively. Those of IGFBP-3(ng/mL) were $559.2{\pm}215.2$, $1,333.3{\pm}692.5$, $2,254.6{\pm}1,513.8$, $2,447.1{\pm}1,464.2$, $1,533.6{\pm}807.4$, respectively. For girls, the mean serum levels of IGF-I(ng/mL) according to five age groups were $53.3{\pm}9.5$, $99.3{\pm}45.8$, $69.6{\pm}51.1$, $106.2{\pm}67.0$ and $145.1{\pm}127.8$, respectively. Those of IGFBP-2 (ng/mL) were $9.1{\pm}7.4$, $5.3{\pm}0.9$, $6.9{\pm}2.0$, $10.5{\pm}3.0$ and $7.9{\pm}1.3$, respectively. Those of IGFBP-3(ng/mL) were $858.2{\pm}433.4$, $1,834.8{\pm}851.3$, $1,404.3{\pm}570.2$, $2,203.5{\pm}899.4$ and $2,029.3{\pm}1,316.7$, respectively. There were significant positive correlations observed between IGF-I and IGFBP-3 levels(r=0.589, P=0.000). Conclusion : IGF-I and IGFBP-3 levels increased as children get older. The peak level of IGFBP-3 was observed in late childhood for both boys and girls, suggesting a current trend of children reaching peak growth velocity before adolescence. The IGFBP-2 level was higher in neonates compare to infancy, suggesting that IGFBP-2 is an important substance for fetal growth.