• 한국재료학회지
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• 제29권3호
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• pp.155-159
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• 2019

Surface plasmon resonance is the resonant oscillation of conduction electrons at the interface between negative and positive permittivity material stimulated by incident light. In particular, when light transmits through the metallic microhole structures, it shows an increased intensity of light. Thus, it is used to increase the efficiency of devices such as LEDs, solar cells, and sensors. There are various methods to make micro-hole structures. In this experiment, micro holes are formed using a wet chemical etching method, which is inexpensive and can be mass processed. The shape of the holes depends on crystal facets, temperature, the concentration of the etchant solution, and etching time. We select a GaAs(100) single crystal wafer in this experiment and satisfactory results are obtained under the ratio of etchant solution with $H_2SO_4:H_2O_2:H_2O=1:5:5$. The morphology of micro holes according to the temperature and time is observed using field emission - scanning electron microscopy (FE-SEM). The etching mechanism at the corners and sidewalls is explained through the configuration of atoms.

• 융합정보논문지
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• 제9권3호
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• pp.1-7
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• 2019

업무용 PC에 다양한 사이버 공격이 발생하고 있다. PC 보안 위협을 줄이기 위해 사전에 취약점 진단을 통해서 예방하고 있다. 하지만 국내의 취약점 가이드는 진단 항목이 업데이트되지 않아서 이 가이드로만은 대응하기가 어렵다. 본 논문에서는 최근 PC의 사이버 침해사고 사례와 보안 위협에 대응하기 위한 국외의 기술적 취약점 진단 항목에 대해서 살펴본다. 또한, 국외와 국내의 기술적 취약점 진단항목의 차이를 비교하여 개선된 가이드를 제시한다. 제안한 41개의 기술적 취약점 개선 항목을 통하여 다양한 보안 위협으로부터 대응할 수 있다는 것을 알 수 있었다. 현재는 알려진 취약점에만 주로 대응이 가능하지만 이 방법의 가이드 적용을 통해 알려지지 않은 보안 위협을 감소시킬 수 있을 것으로 기대한다.

• Parasites, Hosts and Diseases
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• 제61권1호
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• pp.15-23
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• 2023

Concerns about foodborne illnesses caused by Kudoa septempunctata are steadily growing, but reports of K. septempunctata in clinical and food specimens related to food poisoning in Korea are limited. This study aimed to genetically identify K. septempunctata in patients with acute diarrhea and in clinical and food samples related to food poisoning caused by sashimi consumption. Both real-time and nested polymerase chain reaction assays were performed to detect K. septempunctata 18S and 28S rDNA genes in the stools of 348 patients with acute diarrhea, 11 samples (6 stool and 5 rectal swab samples) from patients with food poisoning, and 2 raw Paralichthys olivaceus samples collected from a restaurant where a food poisoning incident occurred. K. septempunctata was identified in 5 clinical specimens (4 stools and 1 rectal swab) and 1 P. olivaceus sashimi sample. All detected K. septempunctata were of genotype ST3. This is the first study to identify K. septempunctata in both patients and food samples with epidemiological relevance in Korea, providing evidence that it is a pathogen that causes food poisoning. Also, this is the first study to confirm the presence of K. septempunctata genes in rectal swabs. Despite continuing suspected occurrences of Kudoa foodborne outbreaks, the rate of identification of K. septempunctata is very low. One reason for this is the limitation in obtaining stool and vomit samples for the diagnosis of Kudoa infection. We strongly suggest the inclusion of rectal swabs among the diagnostic specimens for Kudoa food poisoning.

• 생태와환경
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• 제37권1호통권106호
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• pp.57-63
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• 2004

서낙동강에서 $^{14}C$법으로 1996년 1월부터 10월까지 식물플랑크톤의 1차 생산성을 측정하였다. 서낙동강은 수심이 얕고, 국내 호수와 하천 중에서 가장 수질오염이 심한 곳으로 진광층의 깊이는1.4${\sim}$2.1 m 범위였다. 식물플랑크톤의 chi-a 농도는 67${\sim}$894 ${\mu}g\;L^{-1}$ 범위였고, 8월에는 chi-a 농도가 크게 증가하였다. 최대 물질생산성은 수표면 ${\sim}$0.4 m 깊이에서 나타났으며 2.1${\sim}$4.3 mg C mg $chl-a^{-1}$ 범위였다. 광합성 (P)-광(I)의 관계에서 식물플랑크톤의 광합성 저해는 높은 고광에서 현저히 저해되었으나 Microcystis가 대발생한 기간에는 광저해 현상이 나타나지 않았다. Chl-a 당 식물플랑크톤의 1차 생산성은 입사 광에너지의 양에 비례하였으며 면적 당 1차 생산성은 chl-a현존량과 직선적으로 비례하여 식물플랑크톤의 1차 생산성은 결과적으로 생물량과 광의 함수였다. 과거 자료를 수집한 결과. 낙동강 하구 지역에서 식물플랑크톤의 생산성은 하구둑 건설(1987년) 이후 해가감에 따라 점진적으로 증가하여 이 지역의 부영양화 현상을 반영하였다. 식물플랑크톤의 연 생산성 개념에서 평균 10 ${\mu}g\;chl-a\;L^{-1}$의 생물량 증가는 30 mg C $m^{-2}\;day^{-1}의 단위면적 당 생산성 증가를 가져왔다.

• 한국광학회지
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• 제33권1호
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• pp.28-34
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• 2022

그래핀 전극 아래에 놓인 다층 그래핀 존 플레이트로 구성된 적외선 프레넬 렌즈의 초점 성능을 전산모사를 통해 조사한다. 여기서 패턴된 다층 그래핀의 페르미 에너지 준위(E_F)는 그 위에 놓인 그래핀 전극에 의해 조절된다. 4 ㎛에서 30 ㎛까지의 광대역 파장에서 유리 기판 위에 놓인 8층 그래핀 존 플레이트와 그래핀 전극의 반사도 대비비에 따른 프레넬 렌즈 효과를 분석하였다. 반사도와 반사도 대비비를 고려한 최적 파장인 8 ㎛ 입사파가 초점거리 240 ㎛인 프레넬 렌즈에 입사 시, 다층 그래핀의 E_F가 0.4 eV에서 1.6 eV로 증가함에 따라 초점 세기가 4.3배, 그래핀 층수가 2층에서 8층으로 증가함에 따라 5.8배 강화되었다. 이를 통해 인가된 E_F에 따라서 다중 초점(240 ㎛ 및 360 ㎛) 성능을 보이는 그래핀만으로 구성된 IR 프레넬 렌즈 구조를 초박형 렌즈 플랫폼으로 제안한다.

• 한국해안해양공학회지
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• 제11권4호
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• pp.201-215
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• 1999

입구폭이 좁고 직사각형 형태인 감천항에서 수압식 파고계를 이용한 장·단주기파 및 유속계를 이용한 항입구 유속관측을 실시하였다. 수압 자료에 경향 제거와 Butterworth 고주파수 통과 필터를 적용하여 조석 성분을 제거하였다. 스펙트럼 밀도의 평활화시 주파수폭을 일정하게 유지하는 일정평활화법에 비해 저주파수에서 고주파수로 가면서 폭을 증가시키는 점증평활화법이 장·단주기측에서 모두 만족할 만한 해상도를 보이는 것으로 나타났다. 후자를 현장관측 자료에 적용하여 구한 스펙트럼 밀도와 상대진폭비를 기준하여 감천항의 부진동 모드를 검토하였다. 전체 자료를 분석한 결과 감천항의 Helmholtz 공진 모드는 주기 31.7분에서 상대진폭비 9.2를 보여 동해안의 여러 항만에 비해 상당히 큰 값을 나타냈으며, 제 2 및 제 3 공진주기는 10.3분과 5.4분으로 제시되었다. 한편, 길이를 1일로 분할한 자료들의 분석결과 폭풍시에는 평상시에 비해 스펙트럼 밀도가 매우 컸을 뿐만 아니라 제2 및 제 3 공진의 출현 현상이 우세한 것으로 나타났다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.213-213
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• 2012

It has been known that quantum confinement effect of CdSe nanocrystal was observed by increasing the number of deposition cycle using successive ionic layer adsorption and reaction (SILAR) method. Here, we report on thermally-induced quantum confinement effect of CdSe at the given cycle number using spin-coating technology. A cation precursor solution containing $0.3\;M\;Cd(NO_3)_2{\cdot}4H_2O$ is spun onto a $TiO_2$ nanoparticulate film, which is followed by spinning an anion precursor solution containing $0.3\;M\;Na_2\;SeSO_3$ to complete one cycle. The cycle is repeated up to 10 cycles, where the spin-coated $TiO_2$ film at each cycle is heated at temperature ranging from $100^{\circ}C$ to $250^{\circ}C$. The CdSe-sensitized $TiO_2$ nanostructured film is contacted with polysulfide redox electrolyte to construct photoelectrochemical solar cell. Photovoltaic performance is significantly dependent on the heat-treatment temperature. Incident photon-to-current conversion efficiency (IPCE) increases with increasing temperature, where the onset of the absorption increases from 600 nm for the $100^{\circ}C$- to 700 nm for the $150^{\circ}C$- and to 800 nm for the $200^{\circ}C$- and the $250^{\circ}C$-heat treatment. This is an indicative of quantum size effect. According to Tauc plot, the band gap energy decreases from 2.09 eV to 1.93 eV and to 1.76 eV as the temperature increases from $100^{\circ}C$ to $150^{\circ}C$ and to $200^{\circ}C$ (also $250^{\circ}C$), respectively. In addition, the size of CdSe increases gradually from 4.4 nm to 12.8 nm as the temperature increases from $100^{\circ}C$ to $250^{\circ}C$. From the differential thermogravimetric analysis, the increased size in CdSe by increasing the temperature at the same deposition condition is found to be attributed to the increase in energy for crystallization with $dH=240cal/^{\circ}C$. Due to the thermally induced quantum confinement effect, the conversion efficiency is substantially improved from 0.48% to 1.8% with increasing the heat-treatment temperature from $100^{\circ}C$ to $200^{\circ}C$.

• Journal of Nutrition and Health
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• 제13권1호
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• pp.15-26
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• 1980

The main purposes of the nutrition and clinical surveys were to provide baseline information on the nutritional status of pre-school children in rural health demonstration project areas of the Korea Health Development Institute (KHDI) for nutrition guidance services for the MCH target group. The survey covered a total of 222 pre-school children and 135 mothers in Okgu Gun, Cholla Pukto Province from August 10 to August 17, 1979. The survey results are summarized as follows: 1) Family Environment Seventy percent of the households had more than three children, and the mean family sire was 6. Sixty-nine percent of the mothers and 47% of the fathers of the surveyed households were educated at or below the primary school level. The majority, 70% of the mothers, were aged between 20 years and 35 years. 2) Anthropometric Measurements and Hemoglobin Value 4.5% of the children were lower than 80% weight for age of the Korean standard, and 5.4% were lower than 85% arm circumference for age of the Jelliffe's standard resectively, and those were suffering from protein-energy malnutrition. Angular stomatitis were observed on 66.2% of the subjects. Mean hemoglobin value was 11.1g/100m1, and 44.2% of the subjects were categorized as anaemia. 3) Food and Nutrient Intake of animal foods was very low, ranging from 2.9 to 17%. Consumption of eggs was less than 2% of total food intake, and intake of legumes was also very scanty, between 0.8 to 3.7%. These data present evidence of very poor protein intake, quality as well as quantity. Energy intake of children was 60.0 to 64.4% of the recommended allowance, and mean protein intake only met 47.4% of the recommendation. Low intake of vitamins except thiamin were also found. 4) Mother's Nutrition Knowledge Eighty-five percent of the mothers were entirely ignorant regarding the 'five basic food group' which is most important fact on food and nutrition guidance. Mean knowledge score from 14 basic questions about food and nutrition was as low as 5.1. There was a significant positive correlation between mother's educational level and nutrition knowledge score. 5) Family Planning Variable There were significant correlation among maternal, family planning variables, and some of the nutritional and physical measurements. The study revealed that the mother's educational level and nutrition knowledge score are more crucial factors than the family planning variables on effecting food intakes on children. Recommendation : According to the results of the surveys, there were high incident rates of nutritional anaemia and angular stomatitis among pre-school children, and most of rural women had very limited knowledge about food and nutrition. As a main part of the health education activities, the community health workers should provide nutrition education to the village mothers to improve the nutrional status of young children in rural areas. Nutrional promotion at the primary health care level should be mainly based on appropriate nutrition education.

• 부모자녀건강학회지
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• 제6권1호
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• pp.18-30
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• 2003

Congenital heart disease is the most frequently shown congenital disease among children, most of them can be corrected with operation. However, Patients and their parents need nursing intervention when they face this risky incident of operation. Therefore, parents' experiences are absolutely needed to plan nursing intervention to give practical help to the patients and their parents. The purpose of this study is to provide basic resources to develop a feasible intervention program for the parents by understanding the experiences related to the informed consent of cardiac surgery of their child. From January to June 2003, 10 parents of children patients with congenital heart disease were interviewed who filled out Operation Agreement before the primary operation after they are diagnosed as congenital heart disease in pediatric chest surgery of A hospital in Seoul. They were asked to give opinion regarding pre-operation needs and the interviewed information was analyzed. The results of this study are as follows : Firstly, they were asked what they felt before they were told about the operation of their children from the doctor before filling out the informed consent of operation. They felt 1) vague, 2) confusion of choose, 3) risky, 4) resented, 5) uneasy, 6) guilty, and 7) the burden of operation. Secondly, they were asked what they felt after they filled out the informed consent of operation and the doctor gave them detailed information on the operation of their children. They felt 1) confused, 2) responsible, 3) rejected, 4) angry, 5) plain, 6) to have hope, 7) trying to trust medical people, 8) that consolation is needed, and 9) conditional reduction of the burden of operation. Thirdly, followings are the categories of congenital parents' demand before operation based on the analysis of experiences related to the preparation of the informed consent of operation. 1) Information Demand (1) Anticipatory information (2) Concrete and precise information (3) Individual information 2) Support (1) Empathy (2) Parental supporting (3) Support of parents in the same situation 3) Education and consulting (1) Children-oriented Education (2) Consultation Considering the results of this study, parents of the child with congenital heart disease seem to have various emotional experiences related to filling out the informed consent and they need concrete and practical helps before cardiac surgery. This study proposes that systematic nursing intervention is needed according to the needs of the parents who have the child with congenital heart disease before operation in the field of child health nursing.

• 한국광학회지
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• 제28권4호
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• pp.153-157
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• 2017

지향성적외선방해장비의 정렬 정밀도를 높히고 중량을 감소시키기 위해 적용된 적외선 카메라-레이저 공통광학계 구조에서 영상 성능 저하를 야기시키는 레이저빔 열 영향성을 분석하였다. 높은 에너지 밀도를 가지는 레이저빔이 광부품에 흡수되면 열이 발생하고 온도가 상승한다. 공통광학계 광부품 표면에서 발생한 열은 시스템 투과율을 감소시켜 적외선 카메라의 영상 품질을 저하시킬 수 있다. 지향성적외선방해장비의 운용개념을 고려하여 파장 $4{\mu}m$, 출력 3 W의 레이저빔이 10초간 미러(알루미늄, 실리카 글래스, 실리콘) 및 렌즈(사파이어, 셀레늄화아연, 실리콘, 게르마늄) 재료에 조사되는 상황을 가정하여 온도 분포를 계산하였다. 계산 결과, 미러 재료로는 실리카 글래스, 렌즈 재료로는 사파이어의 온도 상승이 상대적으로 컸고, 재료 온도 분포에 가장 큰 영향을 미치는 요소는 재료의 레이저빔 흡수율과 열전도도임을 확인하였다. 결론적으로 적외선 카메라-레이저 공통광학계에 사용하는 광부품은 흡수율이 낮고 열전도도가 높은 특성을 갖도록 선정되어야 광부품 온도 상승에 의한 적외선 카메라의 영상 품질 저하를 방지할 수 있다.