초음파 공명 분광법(RUS)을 이용한 SiC 입자강화 Al 기지복합재료의 탄성계수 해석

홍순형,주영상,정용무,정현규 韓國非破壞檢査學會 1999 한국비파괴검사학회지 Vol.19 No.3

SiC 입자강화 2124Al 금속복합재료의 강화재 부피분율에 따른 탄성 stiffness를 초음파 공명 스펙트로스코피(resonant ultrasound spectroscopy: RUS) 방법을 이용하여 측정하였다. RUS 방법은 한 개의 소형 시편으로 9개의 독립변수를 가진 사방정계(orthorhombic) 탄성계수를 간단한 실험으로 측정가능함을 보여주었다. SiC 강화재 부피분율 변화에 따른 탄성계수를 측정하였는데 이 경우 초기 추정 탄성계수를 구하기 위해서 부피분율에 따른 미세조직 사진으로부터 강화재의 형상(aspect ratio)과 방향을 고려한 유효 aspect ratio 개념을 도입하였고, Mori-Tanaka 이론식에 의한 계산결과를 이용하였다. 이로부터 계산된 공진주파수와 RUS의 측정 공진주파수 사이를 최소화함으로 정확한 탄성계수를 측정하였다. 측정된 stiffnesses로부터 공학적 탄성계수인 Young's modulus를 계산하였으며, 계산된 Young's modulus와 압출방향으로 인장시험한 Young's modulus를 비교분석하였다. SiC 입자의 부피분율이 증가함에 따라 탄성계수가 증가함을 나타내었고, 탄성 stiffness의 거동은 강화재가 많이 첨가될수록 횡등방성(transversely isotropic) 이 강하게 나타났으며 이것은 압출공정에 의해 강화재 입자의 방향성 재배열에 기인한다. 한편 일정크기 시편에 있어서 기본 공진주파수가 강화재 부피분율에 따라 고주파수 영역으로 이동하는 현상이 관찰되었으며, 이로 부터 비파괴적으로 강화재 부피분율을 예측할 수 있는 가능성을 제시하였다. The dynamic elastic properties of metal matrix composites were investigated by resonant ultrasound spectroscopy(RUS). The composites used in this study consisted of 2124 aluminum alloy reinforced with different concentrations of SiC particles. RUS can determine the nine independent elastic stiffness(C )for the orthorhombic symmetry on a small specimen simultaneously. The elastic constants were determined as a function of the volume fraction. A concept of effective aspect ratio, which combine the aspect ratio and the orientation of reinforcement, was used to calculate the initial moduli from Mori-Tanaka theory for the input of RUS minimization code. Young's moduli can be obtained from the measured stiffnesses. The results show that the elastic stiffness increases with increment of the particle content. The behavior of elastic stiffness indicates that the particle redistribution induced by the extrusion process enlarges the transversely isotropic symmetry as the fraction of reinforced particles increase. This relationship could be used for determination of the volume fractions of reinforcement as a potential tool of nondestructive material characterization.

관동맥질환에서 저밀도 지단백 입자 크기의 분포

임효영,김인숙,승기배,강동헌,전두수,장기육,박준철,이수영,홍순조,최규보 대한순환기학회 1998 Korean Circulation Journal Vol.28 No.8

Haemophilus influenzae Type b 에 대한 급성 후두염의 치료 경험 2 례

이수영(Soo Young Lee),유상호(Sang Ho Yoo),이기선(Ki Sun Lee),홍미애(Mi Ae Hong),김순남(Soon Nam Kim) 대한소아알레르기호흡기학회 1998 소아알레르기 및 호흡기학회지 Vol.8 No.1

Epiglottitis is an uncommon but potentially life threatening infectious disease in young children. And it is rapidly progressing cellulitis of the epiglottis and adjacent structures that has the potential for causing abrupt, complete airway obstruction. The most common cause of acute epiglottitis is Haemophilius influenzae type b (Hib), therefore in USA, the acute epiglottitis is seen less commonly since the wide spread use of immunization against Hib. In Korea, there has been no report of acute epiglottitis caused by known bacterial organism, and a little investigation of the effects of the immunization against Hib, or Hib related respiratory diseases. In this report, we describe two cases of acute epiglottitis caused by Hib, occurred in non-immunized young-male children admitted to Ajou University Hospital. They had visited to the emergency center of Ajou University hospital with the complaints of acute fever, drooling, dysphagia and severe respiratory difficulties. In both cases, we observed the cherry-red colored, severely swollen epiglottis by the direct laryngoscopic examination. Hib was cultured in blood samples from both two cases, and the patients treated successfully by the 3 days of endotracheal intubation and proper antibiotics therapy without any complications such as pneumonia, meningitis, osteomyelitis, or pericarditis.

연령증가에 따른 혈압요소들의 좌심실비대 및 관동맥질환과의 관련성

박재석,박창규,박미영,박재형,김용현,나진오,신성희,서순용,홍순준,박성미,임홍의,김응주,서홍석,오동주,노영무 대한순환기학회 2004 Korean Circulation Journal Vol.34 No.2

EDSA를 이용한 비상발전기 운영에 관한 연구

洪淳錫,崔寧峻 弘益大學校 産業技術硏究所 2005 産業技術 Vol.15 No.-

While everyone who uses electric power desires perfect frequency, voltage, stability, and reliability at all times, this cannot be realized in practice. The supplying utility cannot be expected to provide a perfect power supply because many of the causes of power supply disturbances are beyond the control of the utility. The outage happens but due to many reason. The electricity equipment requires consequently the emergency power supply. We classify the subordinate for quick supply of the emergency power supply and must grope the supply plan. We will find out in this paper through the case study about the emergency power efficient operation plan.

울산지역 유아의 영양 상태에 관한 연구 : Ⅰ. 식습관과 식행동

홍순명,서영은,김현주 울산대학교 2001 생활과학논문집 Vol.3 No.1

본 연구는 울산에 거주하는 학령 전 어린이 142명을 대상으로 식습관과 식행동에 관하여 조사하였다. 조사대상 어린이는 남아 72명, 여아 70명으로 연령분포는 2세에서 7세 이었으며 규칙적인 식사시간을 지키는 남아가 48.6%이고, 여아는 42.9%였다. 조사대상자의 식습관에 있어서는 남아가 '좋은 편(13.9%)', '보통(58.3%)', '나쁜 편(27.8%)'으로 나타났고, 여아의 경우는 '좋은 편(11.4%)', '보통(62.9%)', '나쁜 편(25.7%)'으로 나타났다. 식습관 점수는 '보통'으로 평가되었고 남녀간의 유의적인 차이는 없었다. 조사대상자들의 긍정적인식행동 점수는 남아의 경우, '좋은 편(15.3%)', '보통(76.4%)', '나쁜 편(8.3%)' 이고, 여아는 '좋은 편(15.7%)', '보통(74.3%)', '나쁜 편(10.0%)'로 나타났다. 조사대상자들의 부정적인 식행동 점수는 남아의 경우, '나쁜 식행동이 적은 편(23.6%)', '보통(76.4%)', '나쁜 식행동이 많은 편(0.0%)'이고, 여아는 '나쁜 식행동이 적은 편(21.4%)', '보통(75.7%)', '나쁜 식행동이 많은 편(2.9%)'으로 나타났다. 조사대상자들의 식행동 총점은 '보통'으로 평가되었고, 남녀간의 유의적인(p<0.001) 차이를 나타내었다. 긍정적인 식행동과 식습관 간에는 유의적인 (p<0.05, p<0.001) 양의 상잔성이 있었고, 부정적인 식행동과 식습관 간에는 유의적인 ((p<0.05, p<0.001) 응의 상관성이 있었다 본 연구의 결과는 학령전 어린이에게 적용할 메뉴를 계획하는 프로그램과 영양교육의 자료로 이용될 수 있을 것이다. The nutritional status of 142 preschool children in Ulsan area was surveyed. A survey was conducted on parents using lluestionnaires including general characteristics, subjective symptoms, flood habit and eating behavior The children involved in this study were 72 boys and 70 girls, aged 2 to 7 years old. 48.6% in boys and 42.9% in girls were on'regular'meal times, The food habit score of the subjects was divided into Poor(27.8%), fair(58.3%) and good(13.9%) in boys, poor(25.7%), fair(62.9%) and good(11.4%) in girls. The positive eating behavior score of the subjects was divided into poor(8.3%), fair(76.4%) and good(15.3%) in boys, poor(10.0%), fair(74.3%) and good(15.7%) in girls. The negative eating behavior score of the subjects was divided into poor(0.0%), fair(76.4%) and good(23.6%) in boys, poor(2.9%), fair(75.7%) and good(21.4%) in girls. The relation of the flood habit and positive eating behavior is significantly(p<0.05, p<0.001) positive correlation and the relation of the food habit and negative eating behavior is significantly(p<0.05, p<0.001) negative correlation. The results of this study indicate that nutrition education and menu planning program should be applied to preschool children.

2002학년도 신입생 실태조사

홍순모,이지은,조영아 한국체육대학교 학생생활연구소 2002 學生生活硏究 Vol.- No.8

소아청소년기에 치수치료를 받은 제1대구치의 술전 상태 조사

이순영,이경호,노홍석,정태성,김신 大韓小兒齒科學會 2011 大韓小兒齒科學會誌 Vol.38 No.4

제1대구치는 막중한 역할을 함에도 불구하고, 청소년 이전에 건강을 상실하는 경우가 드물지 않다. 본 연구는 청소년기 이 전에 치수치료를 받게 된 제1대구치의 우식 및 수복 상태와 분포를 파악할 목적으로 시도되었다. 최근 5년간 부산대학교 치 과병원에서 치수치료를 받은 18세 이하 106명 환자의 135개 제1대구치를 대상으로 의무기록에 대한 조사를 시행하여 다음 과 같은 결과를 얻었다. 1. 평균 연령은 11.9세(남 11.5세, 여 12.5세)였고 유의한 성차를 보였으며(p<0.05), 악별로는 상악 47개, 하악 88개로 하악 치아가 더 많았다. 2. 치수 치료 전 치료 기왕력이 없는 치아는 74개, 치수 또는 수복 치료를 받은 치아는 61개였다. 그 중 재치수치료를 받게 된 경우는 22개로 치수절제술-치수절단술의 순이었으며, 단순 수복치료를 받았던 치아는 39개로 복합레진-아말감-GI- 인레이-수복물 탈락 후 미치료-열구전색 및 주조 전장관의 순이었다. 3. 병소 위치가 분류 가능한 73개의 병소 중에서는 근심면 병소가 22개, 교합면 혹은 협설면 병소 39개, 원심면 병소가 12 개를 차지하였다. In clinical dentistry, it is not difficult to meet the permanent first molars with severe coronal caries lesions in children or adolescents. The circumstances surrounding the first molars of children and adolescents are so immature and imperfect compared with those of adults. So we thought it significant to understand the status of these teeth at the moment of endodontic treatment and immediate cause of it. 106 patients with 135 permanent molars necessitating endodontic treatment in childhood and adolescence were included in this study, and the dental records and radiographs were examined. 1. The mean age was 11.9 year (male 11.5, female 12.5) and the result shows significant difference between gender(p<0.05). The mandibular teeth took more than half percentage than maxillary teeth. 2. Of 135 teeth, 45.2 percent of teeth had history of dental treatment previously and 16.3 percent of teeth showed necessity of re-endodontic treatment. 3. Of 73 teeth, 22 teeth had mesial-wall cavity causing endodontic treatment, 39 had occlusal cavity, and 12 had distal cavity.

여성용 춘추복지의 태에 관한 연구 (제1보) : 태의 주관적 평가척도 개발을 중심으로 Development for the Subjective Hand Evaluation Scale

홍경희,김재숙,박춘순,박길순,이영선,김재임 한국의류학회 1994 한국의류학회지 Vol.18 No.3

KES-F system is widely used in hand evaluation, however, it has encountered some challenges, such as the overlapping of primary hand value, lack of predictability in case of women's thin dress, difficulties in communication due to complexity of primary hand expression and cultural differences in subjective evaluation. Therefore, this study was intended 1) to find out the Korean primary hand expressions (factors) of the overall concept of fabric hand associated with women's spring-fall dress fabrics, 2) to develope the fabric hand attributes of those fabrics and 3) to show whether there are any differences between Korean textile experts and non-experts in terms of the concept of fabric hand descriptors of hand attributes. Data base of hand descriptors were collected by extensive interview 60 experts and 10 non-experts using 110 spring-fall dress fabrics. Finally, hand of selected fabrics was assessed by 205 experts and 265 non-experts using 7-point scale of 26 descriptors based on the data base. Subjective ratings were analyzed by common factor analysis with varimax rotation. It was found that Korean primary hand expression indicated rather simple property, hence, did not equate exactly with Japanese experssion(e.g. koshi, shinayakasa, etc.) which contains several material properties. There were differences in stretch & resilience, especially liveliness, between the judgement of non-expert than to experts. Surface-related category was more important to non-experts than to experts. Slight differences were found between both groups in terms of preferred descriptors. Important descriptors as a rating scale were suggested.

편성조직과 게이지에 따른 면 위편성물의 구조적 특성변화

홍수숙;고순영;이연희;박명자 한양대학교 2005 韓國 生活 科學 硏究 Vol.25 No.2

The scoured and undyed 100% cotton yarn (2/30's) were weft-knitted from 13 different stitches with 7 and 12 machine gauge using a V-bed knitting machine. Structure of knit fabrics was characterized and analyzed: fabric length and width, fabric count, fabric weight per area, and fabric thickness were measured. The thickness of the full cardigan 2✕2 and 4✕4 rib presented the highest values due to usage of tuck stitch. The fabric width of 4✕4, 1✕1, and 2✕2 rib stitches were the narrowest group resulted in relaxation shrinkage after knitting. Also 4✕4rib stitch gave the highest value in fabric density and weight. Fabric stitch and structure were well co-related each other, which give the changes of fabric appearance and properties.