• 제목/요약/키워드: The 90’s

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$Co_{90}Fe_{10}$ 박막 및 $Co_{90}Fe_{10}/SiO_2$ 다층박막의 고주파 자기특성 (High Frequency Magnetic Characteristics of $Co_{90}Fe_{10}$ Thin Films and $Co_{90}Fe_{10}/SiO_2$ Multilayers)

  • 윤의중;진현준;박노경;문대철;김좌연
    • 한국자기학회지
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    • 제8권5호
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    • pp.300-307
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    • 1998
  • Co90Fe10 단일박막층은 고진공 RF magnetron sputtering 장비를 이용하여 여러 가지 기판(glass, Si, polyimide) 위에 적층되었고 ~1000$\AA$ 두께를 가진 Co90Fe10 박막은 우수한 고주파 자기특성을 나타내었다. 10$\times$[100 nm co90Fe10/ 100 nm SiO2] 다층 박막의 자화값은 예측된 값과 거의 일치하였으며 Han값(=124 Oe)도 예측된 30$\leq$Han$\leq$125 Oe 범위 내에 있음을 알 수 있었다. 자성 다층 박막의 자화율(=$\mu$,=$\mu$,-j$\mu$r")의 주파수 특성은 자성 다층 박막과 도체로 이루어진 층상구조를 갖는 microstrip line을 network analyzer에 연결하여 전송 특성(S11, S21 파라미터)을 측정함으로써 얻어졌다. $\mu$,"의 주파수 특성은 S-파라미터로 분석되는 magnetic absorption으로부터 얻어졌다. 또한 $\mu$r'의 주파수 특성은 Kramers-Kronig 관계식을 사용하여 $\mu$r"의 주파수 특성으로부터 계산되었다. 이와 같이 얻어진$\mu$r의 주파수 특성 (static 자화율, 공진 주파수)은 계산에 의해서 얻어진 값들과 잘 일치된다는 것을 확인하였다.일치된다는 것을 확인하였다.

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복합판재의 파단 변형률 불확실성을 고려한 탄 관통 잔류속도에 대한 시험 및 수치해석 (Test and Numerical Analysis for Penetration Residual Velocity of Bullet Considering Failure Strain Uncertainty of Composite Plates)

  • 차명석;이민형
    • 대한기계학회논문집A
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    • 제40권3호
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    • pp.281-288
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    • 2016
  • 복합재는 재료 불균질성에 의해 고속 충돌 시 방호성능 자료가 산포한다. 본 연구에서는 다수의 충돌시험으로 복합판재 잔류속도 산포를 확보하고 수치해석으로 예측하는 방법을 정립하였다. 먼저 10개의 동일 시편으로 인장시험을 수행하여 파단변형률 산포를 얻었다. 같은 재료로 제작된 4ply([0/90]s)와 8ply([0/90/0/90]s) GFRP(Glass Fiber Reinforced Plastic) 복합판재에 FSP(Fragment Simulating Projectile) 고속 충돌시험을 동일 조건에서 다수 수행하여 잔류속도 산포를 얻었다. 인장시험에서 얻어진 파단 변형률 분포를 이용하여 수치해석을 수행하였다. 충돌속도는 4ply와 8ply 각각 411.7m/s와 592.5m/s이다. 시험 결과와 비교하여 적절한 잔류속도의 산포를 예측할 수 있었다. 추가적으로 복합판재의 경우 Solid요소 대비 Layered Solid요소로 모델링하면 계산시간이 감소되었다.

딥러닝 기반 80대·90대·100대 남녀 대상 폐암 진단 후 사망률 예측에 관한 연구 (A Study on the Prediction of Mortality Rate after Lung Cancer Diagnosis for Men and Women in 80s, 90s, and 100s Based on Deep Learning )

  • 변경근;이덕규;이세영
    • 한국정보전자통신기술학회논문지
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    • 제16권2호
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    • pp.87-96
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    • 2023
  • 최근 의학계에서도 딥러닝 기술을 이용한 질병의 치료결과 예측 연구가 활발하다. 그러나, 소규모 환자 데이터와 특정한 딥러닝 알고리즘을 선택·활용, 연구를 진행하여 특정 조건 아래에서 의미 있는 결과를 보여주었다. 본 연구에서는 연구 결과의 일반화를 위하여 환자 대상을 좀 더 확대·세분화하여 80대·90대·100대 남녀 대상으로 폐암 진단 후 사망률 예측 연구 결과를 도출하였다. 건강보험심사평가원의 대규모 진료 정보와 다종의 딥러닝 알고리즘을 제공하는 AutoML을 이용, 80대·90대·100대 남녀의 폐암 진단 후 84개월간의 사망률 예측을 위해 Decision Tree, Random Forest, Gradient Boosting, XGBoost, Logistic Regression 등 5개 알고리즘별 모델을 생성하고 이를 통해 예측 성능을 비교하고 사망률에 영향을 미치는 요인에 대한 분석도 추진하였다. 연구 결과, 80대와 90대에서 남성이 여성보다 사망 예측률이 더 높았으며 100대에서는 여성의 사망 예측률이 남성보다 높게 나타났다. 그리고 사망률에 가장 큰 영향을 미치는 요인으로는 치료기간으로 분석되었다.

기공과 간이정신진단검사 및 자기효능감 척도의 관계 고찰 (The Connection between Symptom Checklist-90-R(SCL-90-R), Self-Efficacy Scale(SES) and Qi-gong)

  • 김수현;박선영;정대규
    • 동의신경정신과학회지
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    • 제20권4호
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    • pp.31-52
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    • 2009
  • Objectives : The purpose of this study was to investigate the connection between Symptom Checklist-90-R (SCL-90-R), Self-Efficacy Scale(SES) and Qi-gong. Methods : We investigated 141 oriental medical students in Daegu consisted of 36 subjects training Qi and 105 subjects not training. We had all subjects to reply to demographic questimnaire, SCL-90-R questimnaire and SES questimnaire. We made the Qi-training group write the kinds and periods of Qi seperately. Results & Conclusions : 1. The lower SCL-90-R score, the subjects had higher SES score. Total Self-Efficacy score was connected Somatization, Interpersonal Sensitivity, Depression, Paranoid Ideation, Paranoid Ideation score significantly. General Self-Efficacy score was connected Somatization, Obsessive- Compulsive, Interpersonal Sensitivity, Paranoid Ideation, Paranoid Ideation score significantly. Social Self-Efficacy score was connected Interpersonal Sensitivity, Depression, Anxiety score significantly. 2. The Qi-training group's mean all the details of SCL-90-R lower than the non-training's significantly in Somatization, Obsessive-Compulsive, Interpersonal Sensitivity, Depression, Hostility, Paranoid Ideation, Psychoticism. And the Qi-training group's mean all the details of SES higher than the non-training's, significantly in General Self-Efficacy. 3. In Qi-training group, as training longer, mean Somatization, Interpersonal Sensitivity, Depression, Anxiety, Hostility scores get lower and mean Total Self-Efficacy score get higher significantly.

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곡률을 고려한 CFRP 복합재 적층쉘의 관통특성 -관통에 의한 파괴모드를 중심으로- (Penetration Characteristic of CFRP laminate shell by the curvature -A focus of fracture mode by the penetration-)

  • 조영재;김영남;심재기;양인영
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2004년도 추계학술대회 논문집
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    • pp.1434-1439
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    • 2004
  • CFRP composite materials have wide application in structure materials of airplane, ships, and aero space vehicles because of their high strength and stiffness. This paper is to study the effects of curvature and orientation angle on the penetration characteristics of CFRP laminate shell. They are staked with 8 Ply specimens [0$_2$/90$_2$]$_{s}$, [0/90$_2$/0]$_{s}$ and the stacked of outer plates degree with 12 Ply specimens [0$_3$/90$_3$]$_{s}$, [0$_2$/90$_2$/0]$_{s}$ and [90$_3$/0$_3$], [90$_2$/0$_2$/90]S. They are manufactured to varied curvature radius (R=100,150,200mm and $\infty$). They are cured by heating to the appropriate harding temperature(13$0^{\circ}C$) by mean of a heater at the vaccum bag of the autoclave. Test specimens were prepared with dimensions 100mm$\times$140mm. When the specimen is subjected to transverse impact by a steel ball, the velocity of the steel ball was measured both before and after impact by determining the time for it to pass two ballistic-screen sensor located a known distance apart. In general, kinetic energy after impact-kinetic energy before impact rised in all specimens. This study observed a fracture mode inside the specimen after a penetration test using a digital camera and it examined a fracture mode and a penetration mode to stack of outer orientation angle and curvature.rvature.

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원공노치를 가진 CFRP의 적층방향에 따른 기계적 특성 평가 (The Mechanical Properties Evaluation on Lay-up Orientation Effect of CFRP Laminate Composite with the Hole Notch)

  • 태영일;윤유성;권오헌
    • 한국안전학회지
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    • 제17권1호
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    • pp.25-32
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    • 2002
  • The tensile tests for [0/90]s, [90/0]s, and $[0/{\pm}45/90]s$ laminate composite were accomplished with acoustic sensor and failure processes were recorded by a video camera in real time. Also SEM examinations for fracture and side surface were carried out. The purpose of study is estimation of the failure mechanism and the mechanical properties effected by lay-up orientation for CFRP laminate composite with the hole notch. From the results, mechanical properties were obtained and they are similar between two kinds of cross-ply orientation in CFRP laminate composites, but not on $[0/{\pm}45/90]s$. And accordings to increasing the load, accumulate AE count was increased, regardless of lay-up orientation. Futhermore, failure mechanism was described by a video monitoring and SEM.

청소년 의상에 나타난 포스트모더니즘 현상 (A Study of Postrnodern Phenomenon in Clothings for German youth)

  • 홍기현
    • 한국의류학회지
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    • 제21권3호
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    • pp.581-588
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    • 1997
  • Since 1950 postmodernism shows strong influences in literature, architektuTe, art, clothing and other social and cultural fields. It's main conceptswere individual, pluralistic, unconven- tional and deconstruction of social values. The purpose of thisstudy was to review the influence of postmodernism to German clothing for youth. To achieve this purpose, raga- zinesfor youth ("BKAVO") from 1959 to 1994 surveyed including a number of interviews. The characterizations of postmodernism in fashion are as follows: Sport Clothing has an effect on Oaily Clothing. Exotic phenomenon from south america, africa, asia shows strong in fashion. Subculture(Rocker, Hippie, Punker) is as anti-culture sylnbolically expressed in young fashion which is diffrent from mother-fashion. This appeard in Germany in the 50s, 60san6 70s. However, sub-culture-look in the 80s and 90s is presented only in outer style. It does'nt show any symbolic meanings. "Bricolage" ("mix and match") -concept was appeard in 60s and 70s only in fashion of subculture group. This concept generalized in standard fashion in 80s and 90s.andard fashion in 80s and 90s.

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이방성 재료의 충격거동에 관한 시뮬레이션 (Impact Behavior Simulation of Anisotropic Materials)

  • 안국찬;정대식;김봉환
    • 한국기계가공학회지
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    • 제10권1호
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    • pp.38-46
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    • 2011
  • A study was performed to investigate the dynamic behaviors of fiber-reinforced composite materials subjected to transversely low-velocity impact. For this purpose, the simulation of modified beam finite element based on higher order beam theory for two(isotropic and anisotropic) materials is carried out according to the changes of material property, stacking sequence, geometric dimension and impact velocity of steel ball, etc. Main composite materials for simulation are composed of $[0^{\circ}/90^{\circ}/0^{\circ}/-90^{\circ}/0^{\circ}]_{2s}$, $[0^{\circ}/90^{\circ}/0^{\circ}/-90^{\circ}/0^{\circ}]_s$ and $[0^{\circ}/45^{\circ}/0^{\circ}/-45^{\circ}/0^{\circ}]_{2s}$, $[0^{\circ}/45^{\circ}/0^{\circ}/-45^{\circ}/0^{\circ}]_s$ stacking sequences. The effectiveness of this simulation for qualitative and quantitative evaluations in composite materials subjected to foreign object impact was established.

국내 학생운동에 표현된 저항 패션에 관한 연구 (A Study on the Anti-Fashion Expressed in the Korean Student Movement)

  • 간문자
    • 복식
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    • 제41권
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    • pp.153-168
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    • 1998
  • The purpose of this study is to examine, specifically, the external and internal characteristics of anti-fashion expression in the Korean student movement after the 1945 Liberation. The dress expressed in the student movement represented the purity of student and characterized resistance, and this character expressed strongly in 80s, faded from middle of 90s. Until the 60s, the student movement was not characterized by, so activist students wore dress and suits. It symbolized students as an elite group of society. They added on head-bands to express resistance. In the 70s, activist students wore school uniforms, school military training wear, blue jeans and loose shirts in demonstrations. They tried to express re-bellion against the government and the older gen-eration. In the 80s, the period was remarkably distingusihing by the economic growth at that time. Activist students wore T-shirts with Korean letters and popular paintings specially made, Korean costumes, wrapped in the Taggeuki (Korean national flag), and refused wear on jeans because of anti-Americanism. They also wore masks, muffled their faces, and got their heads shaved. These anti-fashions are very strong expressions for the national independence spirit, national traditional heitage, anti-foreign power and anti-American. In the early 90s, activist students wore reformed Korean costumes specially made group uniforms, after that they wore casual everyday clothes with caps. They tried to express remarkable resistance in the early 90s, but after the mid-90s expression of resistance weakened and faded, so there was no distinction between activist and non-activist. There are the reasons why the student movement changed after the peaceful transfer of political power.

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