• 제목/요약/키워드: Low-Order Features

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GPR 분석을 위한 자갈궤도 자갈의 감쇄특성을 이용한 이득함수 개발 (New Gain Function Based on Attenuation Characteristics of Ballast Track for GPR Analysis)

  • 신지훈;최영태;장승엽
    • 한국지반환경공학회 논문집
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    • 제18권4호
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    • pp.13-21
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    • 2017
  • 자갈궤도는 100여년 이상 전세계적으로 널리 사용되는 궤도구조로 저렴한 초기 건설비용, 유연한 유지보수와 진동 및 소음의 저감효과가 있지만, 열차운행에 따라서 지속적인 침하가 발생하는 단점이 있다. 이로 인해 지속적인 유지보수가 필요하며, 최근 열차의 속도, 용량, 중량의 증가로 유지보수비용이 증가하고 있는 실정이다. 파울링(fouling)은 노반 세립분이나 자갈입자가 파쇄되면서 발생한 세립분이 자갈 사이의 공극을 메우는 현상으로 배수가 나빠지고, 자갈궤도의 침하를 가속화시키는 등 자갈도상의 열화의 주원인으로 지목되고 있다. 본 논문에서는 GPR(Ground Penetrating Radar)을 이용하여, 도상의 상태를 평가 할 수 있는 분석방법을 제안하였다. 경험에 의존하는 기존의 분석기법을 대신하여, 고속선에 사용되는 자갈의 감쇠 특성을 반영한 이득함수(gain function)를 제안하였다. 실내 박스 실험과 실모형 실험을 통해 제안한 이득함수로 증폭한 GPR신호에 힐버트 변환을 추가로 적용하여 자갈층과 노반층에서 반사된 신호의 세기변화를 깊이에 따라 계산하였다. 이로부터 신호의 세기가 비교적 크게 변화하는 곳을 파울링층과 노반층의 경계로 구분할 수 있었다. 다만 현장적용을 위해서는 침목의 영향을 분리하고 전자기파 분산특성 등에 대한 추가 연구가 필요할 것으로 사료된다.

사전의료지시의 한계 (The Limitations of Advance Directive)

  • 오세혁;정화성
    • 의료법학
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    • 제11권2호
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    • pp.239-274
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    • 2010
  • Advance directive refers to a description of the treatment method a patient wants to be provided with in case where the person is unconscious or lacks an ability to decision making in a future period or a declaration of intention that delegates and appoints another person who makes a decision regarding a treatment method on behalf of the person. Advance directive is usually a document form, but oral statement is acceptable as well. Advance directive may have a variety of forms though, it basically consists of two basic forms. That is, one is a living will, and the other is a surrogate decision making. Though the importance of advance directive has been emphasized, and the necessity of adopting the system has been strongly argued for so far, the debates on criteria, method, and procedure alike have not yet reached an agreement. It is because even the concept of advance directive is more or less ambiguous, and each specific method has its own theoretical limitations and practical constraints. Thus the inquiries on advance directive raised in the study are summarized as the meaning, practicability, and philosophical foundation of the advance directive. Firstly, the theoretical limitations of Advance directive may be categorized into conceptual and moral limitations. In case of conceptual limitations, authors of advance directives may not be well aware, in advance, of the particular situation in which he or her will experience in the future, and patients may experience the change in his or her values and lack the understanding and information about the future situation due to the changes in treatment methods. In case of moral limitations, a patient has a limited moral autonomy right and self identity that have an impact on his or her preference. Secondly, in case of practical constraints for advance directive, there exist cultural features, low ratio of documentation, as patients themselves admit, and low predictability and stability of patient's own preference regarding life-sustaining care. And the problem of validity and accuracy in proxy's decision making is also raised. Those who administer a living will, especially, may have a difficulty in understanding the directive by a patient, so that the accuracy of execution cannot be secured. In the sense, it is needed to implement a legal device in order to solve such problems. In summary, it is urgently required to understand the limitations and explore desired alternatives to overcome the relevant problems in advance, which must contribute to successfully adopting and effectively operating the advance directive system in Korea.

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고속도로 교통사고의 계절성 검증과 요인분석 (중부고속도로 사례를 중심으로) (Analysis of Seasonal Variation Effect of the Traffic Accidents on Freeway)

  • 이용택;김양지;김대현;임강원
    • 대한교통학회지
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    • 제18권5호
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    • pp.7-16
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    • 2000
  • 본 논문은 고속도로사고의 시간-공간적 반복성을 검증하고 이러한 현상의 원인을 규명하는 연구이다. 이를 위해 중부고속도로를 대상으로 계절성 유무검증과 계절성인자의 요인분석을 위한 계절군집별 모형을 개발, 해석하였다. 먼저 자가조직지도와 사고지표(월평균 사고율과 월평균 대물피해환산치) 분석을 통해, 국내 고속도로사고의 계절성이 존재하는 것을 확인하였으며, 집합적 계층적 군집분석기법을 사용하여 적정 계절군집수를 분석한 결과 겨울군집 봄가을군집, 여름군집의 3개 군집으로 분리되었다. 또한 해당 군집의 대표값은 겨울군집이 사상 자수와 사고차량수는 적은 반면 사고의 치명도는 매우 높은 것으로 나타났으며, 여름군집은 사상자수와 사고차량수는 많은 반면, 사고의 치명도는 다소 낮은 것으로 나타났다. 또한 계절군집별로 회귀모형식을 개발하여 계절군집별 사고특성을 검토한 결과, 계절성 유발인자(교통량, 안개, 결빙일수, 강설량, 강우량)와 계절군집의 사고가 매우 밀접한 관계를 가지고 있었으며 이들의 차이에 따라 국외 또는 지역별로 계절성의 특성이 다소 달라지는 것으로 분석되었다. 아울러, 이러한 연구결과는 사고다발지점선정기법, 사고예측 및 기술 모형 개발, 안전 관리를 위한 재원의 배분문제 등의 사고안전관리계획을 합리화하는 기초자료로 활용되리라 판단된다.

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글로우방전을 이용한 폴리에스테르섬유의 발수가공 (Water Repellent Finishes of Polyester Fiber Using Glow Discharge)

  • Mo, Sang Young;Kim, Gi Lyong;Kim, Tae Nyun;Chun, Tae Il
    • 한국염색가공학회지
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    • 제5권4호
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    • pp.29-41
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    • 1993
  • In order to surface Hydrophobilization of Poly(ethylene terephthalate) (PET) fiber samples were treated in the atmosphere of CF$_{4}$ or $C_{2}$F$_{6}$glow discharge. The sample used in this study was PET film which is 75$\mu$m thick made by Teijin, O-Type(Japan). The cleaned samples were placed in plasma reactor made of pyrex glass cylinder, and plasma processing was carried out by glow discharge of CF$_{4}$ or $C_{2}$F$_{6}$ gas, being continuously fed by gas flow and continuously pumped out by a vacuum system. Electric power source for generate plasma state was sustained alternating current(60Hz) and voltage was sustained 600 volt. The duration of plasma treatment varied from 15 to 120 seconds except special case, the monomer gase pressure varied from 0.02 to 0.3 Torr and power range was 10 to 90 watts. The hydrophobic features of changed PET surface were evaluated by contact angle measurement and surface chemical characteristics were analyzed by ESCA. Results can be summerized as follows. 1. The most favorable setting position of substrate was the center area between the two electrodes. 2. $C_{2}$F$_{6}$ discharge current was lower than that of CF$_{4}$ when same voltage was sustained. Treated efficiency between CF$_{4}$ and $C_{2}$F$_{6}$ did not revealed significant differences under same electric power(wattage). 3. When monomer pressure is very low below 0.02 torr, as though substrate is exposed to CF$_{4}$ or $C_{2}$F$_{6}$ plasma, it tend to be hydrophilic through a little of fluorine bond and a great deal of oxidizing reaction. 4. There brought good hydrophobilization when monomer pressure was more 0.1 torr and duration of glow discharge treatment was over 45 seconds. When monomer pressure was too high, discharge current became low. Although prolong the duration, there was no more high hydrophobilization. 5. According to ESCA analysis, there were a little CF bond and a prevailing CF$_{2}$ bond in CF$_{4}$-treated substrate. There were CF$_{3}$, a little CF and a prevailing CF$_{2}$ bond in $C_{2}$F$_{6}$-treated substrate.d substrate.

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갑상선의 $H\"{u}rthle$씨 세포 종양 ($H\"{u}rthle$ Cell Tumor of the Thyroid)

  • 정웅윤;김석주;박정수
    • 대한두경부종양학회지
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    • 제13권2호
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    • pp.206-212
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    • 1997
  • H$\"{u}$rthle cell neoplasm of the thyroid gland is an uncommon, but potentially malignant lesion. However, in many instances, the malignant potential of the H$\"{u}$rthle cell neoplasm is very difficult to judge histologically. For this reason, the biologic behavior of this tumor and its optimal treatment have come under considerable debate in recent years. In order to review the clinicopathologic features of the H$\"{u}$rthle cell neoplasm and to determine its optimal treatment modalities, we studied 26 patients with path logical proof of H$\"{u}$rthle cell tumor from January 1987 to September 1997. We also performed an immunohistochemical study using the monoclonal antibodies against antigen CD34 for the angiogenic activity of this tumor and evaluated the differences of microvessel density(MVD) between benign and malignant tumors. The age of the patients ranged from 1 to 71 years with a mean of 44.2 years. There were 6 males and 20 females(M : F= 1 : 3.3). The accuracies of fine needle aspiration biopsy and frozen section were very low; 6.3% and 34.8%, respectively. There were 20 benign tumors and 6 malignant tumors(23.1%). All the malignant tumors were microinvasive(intermediate) type which had minimal capsular invasion and most of them(5 cases) were diagnosed postoperatively. Any specific clinicopathologic differences were not seen between benign and intermediate groups. Most of the cases had conservative surgeries(15 ipsilateral lobectomy-isthmusectomy, 7 subtotal thyroidectomy) while total thyroidectomy was performed in 4 cases. Of the cases with malignant tumor, 2 had ipsilateral lobectomy-isthmusectomy, 3 had subtotal thyroidectomy and the remaining 1 had total thyroidectomy. Mean size of the tumors was 3.0 cm(0.1- 8.5 cm) in the greatest diameter and multiple tumors were seen in 6 cases(23.1 %). During the follow-up period, only one recurrence(3.8%) of benign tumor occurred but distant metastasis or cause-specific death was seen in the benign or intermediate groups. Mean MVDs of the benign(n=13) and intermediate(n=6) groups were $121.7{\pm}35.3$ and $114.3{\pm}31.7$, respectively and there was no statistical significance between them. In conclusion, because of the low accuracies of fine needle aspiration biopsy and frozen section for the H$\"{u}$rthle cell neoplasm, the extent of surgery could be individualized based on permanent pathologic examination; Conservative surgery would be adequate for patients with benign or intermediate H$\"{u}$rthle cell neoplasm and total or near-total thyroidectomy for those with definite malignancy.

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HER-2/neu Status: A Neglected Marker of Prognostication and Management of Breast Cancer Patients in India

  • Zubeda, Syeda;Kaipa, Prabhakar Rao;Shaik, Noor Ahmad;Mohiuddin, Mohammed Khaliq;Vaidya, Sireesha;Pavani, Boddana;Srinivasulu, Mukta;Latha, Manolla Madhavi;Hasan, Qurratulain
    • Asian Pacific Journal of Cancer Prevention
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    • 제14권4호
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    • pp.2231-2235
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    • 2013
  • Background: Categorizing breast tumors based on the ER, PR and HER/Neu 2 receptor status is necessary in order to predict outcome and assist in management of breast cancer. Herfe we assessed this question in South Indian patients. Materials and Methods: A total of 619 formalin fixed paraffin embedded breast tumor tissues were collected from pathology archives after receipt of ethical clearance. With the help of primary and secondary conjugated antibodies, expression status of ER, PR and HER2/neu was determined. All the experimental data were assessed for correlations with histopathological features of tumors and clinical presentation of the subjects. Results: In the present study, the ages ranged from 20-87 years with a mean of $50.0{\pm}12.q$ years, and majority of the tumors (84%) were of infiltrating duct cell carcinoma type. Assessment of ER, PR and Her-2/neu expression showed that 46% were triple negative. Interestingly, an inverse relation between ER, PR and HER-2/neu was apparent in 41.2% (p<0.0001) of the tumors, of which 24.5% (p<0.0001) were ER and PR co-negative but HER-2 positive. Conclusions: ER and PR positive tumors are less common (i.e<30%) compared to HER-2/neu positive tumors (i.e>50%) in Indian breast cancer patients, underlining the need for effective diagnostic screening and specific therapeutic managements in order to improve the survival rate of patients in low resource countries such as India.

금강사지 출토 대형 토기의 보존 - 대형 토기접합에 사용된 순간 접착제에 대한 연구 - (Conservation Process of Large-earthen ware in Geumgangsa Temple Site - A Study on the Cyanoacrylate Adhesive Used for Large-earthen Ware Joining -)

  • 이다혜;황현성;신민경
    • 박물관보존과학
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    • 제13권
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    • pp.1-11
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    • 2012
  • 국립중앙박물관에서는 수장고에 보관 중이던 미등록 유물들을 연차적으로 등록하는 사업을 진행하던 가운데 복원 작업이 시작된 금강사지 출토 대형 토기편을 설명하고 전반적인 보존처리과정을 소개하고자한다. 대형 토기는 총 600여점을 40여개의 유물상자에 파손된 상태로 별도 보관하고 있었으며 형태나 크기, 사용 용도, 그리고 몇 개의 토기인지를 전혀 파악할 수 없는 상태였다. 수 많은 토기 조각과 토기 무게로 인해 우선 재질별, 토기 두께와 표면 색감, 그리고 유약 광택도 등 가시적 특징만으로 크게 6개의 토기 편으로 가분류하였으나, 가접합 해 본 결과, 실제로는 한 개의 토기 편임을 알 수 있었다. 이번 복원 과정에서는 매우 크고 무거운 기형의 토기를 접합할 때도 일반적으로 사용되는 순간접착제가 과연 안전한지를 알아보고자 먼저, 예비 실험을 통해 저점도~고점도별 접착속도와 접착강도, 그리고 용해속도를 조사하여 안전성을 확인하였다. 접합 후 결손된 부분의 형태에 따라 다양한 종류의 에폭시 수지를 사용하여 복원하였으며 저부가 편평하지 않고 동그란 형태여서 제대로 서있지 않아 유물을 안정하게 보관하면서도 전시에 바로 사용하도록 전시받침대까지 제작하였다.

컴팩트 플래쉬 방식의 휴대용 산소포화도 측정 시스템 구현 (Implementation of a portable pulse oximeter for SpO2 using Compact Flash Interface)

  • 이한;김영길
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2003년도 춘계종합학술대회
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    • pp.678-681
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    • 2003
  • 컴팩트 플래쉬방식의 휴대용산소포화도와 ECG감시 시스템을 구현하는데 목적이 있다. 먼저 휴대용 산소포화도의 측정은 산소포화도와 맥박을 동시에 측정해서 2채널을 기록하도록 설계했다. 다른 장치없이 환자의 상태를 감지할 수 있고 소형화되고 휴대 가능하게 했다. 환자모니터링에 의해 발생하는 문제점을 해결하기 위해 기저선변동을 없애기 위해 2D 섹터 알고리즘을 적용시킨 아날로그 보정회로를 추가했다. 현재 SpO2모듈은 완성됐지만 컴팩트 플래쉬 방식을 사용하는데는 아직까지 많은 개선의 여지가 있다. ECG감시장치는 3극자 ECG시스템을 적용했다. 필터로는 2가지가 혼합된 방식이다. 하나는 전력선을 없애는 것이고 다른 하나는 기저선 변동을 없애는 것이다. 이것은 DC간섭을 줄이고 전력선의 주파수 간섭을 없애는 효과가 있다. 컴팩트플래쉬 방식으로 환자의 정보를 적은 비용으로 쉽게 기록하고 의료기관에 알릴수 있다.

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인생과 월경 전기 증후군과의 상관관계에 관한 연구 (Premenstrual Syndrome and Personality)

  • 김은주
    • 대한간호학회지
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    • 제18권1호
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    • pp.80-93
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    • 1988
  • This study was planned and carried out to investigate the correlation between premenstrual syndrome and personality in order to provide informations basic to the prevention, alleviation, and care for the premenstrual syndrome. Data on premenstrual syndrome were gatherd from October 20 to 25, 1986 by questionnaire modified by the researcher based on Endicott's Premenstrual Assessment Form. Reliability of the instrument was tested by Cronbach's $\alpha$. Data on personality were gathered in March, 1986, by the high school autorities by standardized Personality Inventory Scale developed by Eung Yun Hwang were used. Subjects numbered 457, 95.2% of the first grade students of H. Girls High School located in Seoul. The correlation and difference between personality traits and premenstrual syndrome analysed by Pearson's Correlation Coefficient, and difference between groups were analysed by the t-test. Personality traits influencing premenstrual syndromal categories were analysed by the multiple regression. The results are as follows : I. The five highist categories of premenstrual syndrome among 18 categories revealed to be Social withdrawal, General discomfort, Lability, Fatigue and Hostility / Anger in rank order. II. Personality traits and Premenstrual syndrome ; 1. Tendency of Psychoneuroses(r=0.43, p<.001), psychoses(r=.39, p<.001) and anti-social behaviors (r=0.43, p<.001) revealed to be significantly correlated to premenstrual syndrome. Hypothesis 1 is accepted. 2. Emotional stability(r= -0.38, p<.001), reflectiveness (r= -0.14, p<.01), masculinity (r= -0.10, p<05) and antonomy (r= -0.12, p<.05) revealed significant correlation, While activity, dominance, sociability and achivement revealed no significant correlation. Hypothesis 2 is partially accepted. III. Significant models of personality traits influencing the premenstrual syndromal categories are ; 1. 5 personality traits : tendency of psychoneuroses, emotional stability, dominance, activity and autonomy revealed to influence Low mood / loss of pleasure significantly. ($R^2$=.19) 2. 3 personality traits ; tendency of psychoneuroses, emotional stability and sociability revealed to influence Lability significantly. ($R^2$=.15) 3. 5 personality traits ; tendency of psychoneuroses, activity, emotional stability, sociability and achievement revealed to influence Anxiety significantly.($R^2$=.18) 4. 3 personality traits : tendency of psychoneuroses, emotional stability and sociability revealed to influence Miscellaneous mood / behavior changes significantly.($R^2$=.18) 5. 3 personality traits : tendency of psychoneuroses, psychoses and reflectiveness revealed to influence Hysteroid features significantly.($R^2$=.16) IV. No significant correlation between irregularity of menstruation and premenstrual syndrome was revealed. No significant difference between group of dysmenorrhea and group of non-dysmenorrhea in premenstrual syndrome was revealed.

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도시지역에서 토지피복 유형별 지표면 온도 예측 분석 (Prediction of Land Surface Temperature by Land Cover Type in Urban Area)

  • 김근한
    • 대한원격탐사학회지
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    • 제37권6_3호
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    • pp.1975-1984
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    • 2021
  • 도시 확장은 도시의 온도를 상승시키고, 이러한 도시의 온도 상승은 사회적, 경제적, 신체적 피해를 초래한다. 이러한 도시열섬을 예방하고 도시의 지표면 온도를 감소시키기 위해서는 도시 공간을 구성하는 지형지물들의 냉각 효과를 계량화하는 것이 중요하다. 이에 본 연구에서는 서울을 대상으로 토지피복 각각의 객체들과 지표면 온도와의 관계를 파악하고자 토지피복지도 6개 클래스로 분류하여 지표면 온도와 객체들의 면적, 둘레/면적, 정규식생지수와의 상관분석과 다중회귀분석을 수행했다. 분석 결과 정규식생지수는 지표면 온도와 상관성이 높게 나타났다. 그리고 다중회귀분석에서도 지표면 온도 예측에 정규식생지수가 다른 계수보다 높은 영향력을 행사했다. 다만 다중회귀분석 결과 도출된 모델들의 설명력은 낮게 나타났는데, 향후 아리랑 3A의 고해상 중적외선 데이터를 연계 활용하여 지속적인 모니터링을 수행한다면 모델의 설명력을 한층 강화할 수 있을 것이다. 그리고 녹지공간의 식생 활력까지 고려한 토지피복 유형과 도시 공간 내 지표면 온도와의 관계를 기반으로 도시계획에 활용한다면 도시의 지표면 온도를 저감하는데 큰 도움이 될 수 있을 것으로 판단된다.