• 한국수학교육학회지시리즈E:수학교육논문집
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• 제37권1호
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• pp.65-84
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• 2023

라그랑주 승수법(Method of Lagrange Multipliers)은 등식 제약조건하에서 미분가능한 함수의 최대, 최소를 구하는 대표적인 방법이다. 선형대수학, 최적화 이론, 제어 이론을 포함하여 최근에는 인공지능 기초수학에서도 널리 활용되고 있다. 특히 라그랑주 승수법은 미분적분학과 선형대수학을 연결하는 중요한 도구이며, 주성분 분석(Principal Component Analysis, PCA)을 포함한 인공지능 알고리즘에 많이 활용되고 있다. 따라서 교수자는 대학 미분적분학에서 처음 라그랑주 승수법을 접하는 학생들에게 구체적인 학습 동기를 제공할 필요가 생겼다. 이에 본 논문에서는 교수자가 학생들에게 라그랑주 승수법을 효과적으로 교육하는데 필요한 통합적인 시야를 제공한다. 먼저 다양한 전공의 학생들이 계산에 대한 부담을 덜고 원리를 쉽게 이해할 수 있도록 개발한 시각화 자료 및 파이썬(Python) 기반의 SageMath 코드를 제공한다. 또한 라그랑주 승수법으로 행렬의 고윳값과 고유벡터를 유도하는 과정을 상세히 소개한다. 그리고 라그랑주 승수법을 간단한 경우에 대한 증명에서 시작하여 일반화된 최적화 문제로 확장하고, 수업에서 학생들이 라그랑주 승수와 PCA를 활용하여 실제 데이터를 분석한 결과를 추가하였다. 본 연구는 대학수학을 지도하는 다양한 전공의 교수자들에게 도움이 될 기초자료가 될 것이다.

• 한국산업정보학회논문지
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• 제27권6호
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• pp.13-23
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• 2022

본 논문에서는 패션 분야의 비정형 데이터 검색을 위한 패션 아이템별 세부 컨포넌트 이미지 분류 알고리즘을 제안한다. 코로나-19 환경으로 인하여 최근 AI 기반 쇼핑몰이 증가하는 추세이다. 하지만 기존의 키워드 검색과 사용자 서핑 행위 기반 개인 맞춤형 스타일 추천으로는 정확한 비정형 데이터 검색에는 한계가 있다. 본 연구는 다양한 온라인 쇼핑 사이트에서 크롤링한 이미지를 사용하여 Mask R-CNN을 활용한 전처리를 진행한 후, CNN을 통해 패션 아이템별 컴포넌트에 대한 분류를 진행하였다. 셔츠의 카라 및 패턴과 청바지의 핏, 워싱 및 컬러에 대한 분류를 진행하였으며, 다양한 전이학습 모델을 비교 분석한 후 가장 높은 정확도가 나온 Densenet121모델을 사용하여 셔츠의 카라는 93.28%, 셔츠의 패턴은 98.10%의 정확도를 도달하였으며, 청바지의 핏은 Notched, Spread, Straight 3가지의 클래스의 경우 91.73%, Regular 핏을 추가한 4가지의 클래스의 경우 81.59%, 청바지의 색상은 93.91%, 청바지의 Washing은 91.20%, 청바지의 Demgae는 92.96%의 정확도를 도출하였다.

• Journal of Platform Technology
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• 제10권3호
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• pp.60-68
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• 2022

AI 기술이 발전함에 따라 자율주행의 안전성에 관한 관심이 대두되고 있다. 최근, 자율주행의 차량이 증가하고 있지만 그에 대한 부작용을 해소하기 위한 노력은 다소 부진한 실정이다. 특히, 야간에 운행되는 자율주행 차량은 더욱 많은 문제들을 안고 있다. 운행의 다양한 환경에서 야간 주행의 환경은 매우 중요한 요소이다. 이에, 본 연구에서는 야간 자율주행 차량에서 핵심적인 문제점으로 부상하고 있는 반대 차량의 전조등 또는 주위 다양한 조명에 의해 발생되는 반사광을 감소시키는 방안을 제안한다. 이를 위하여, 먼저, 야간 주행 중에 센서에 의해 획득한 영상에서 반사광 특성 정보를 활용하여 조명 반사광을 추출한 후, 반사계수를 활용한 각 픽셀의 색상을 찾아 specular 영역을 감소한다. 그 후 영역의 밝기성분만을 이용한 새로운 영역을 찾아 최종적으로 이를 감소하는 방안을 제시한다. 조명 반사광을 완벽히 감소할 수는 없지만 대체적으로 만족할 만한 결과를 얻을 수 가 있었다. 따라서 제안된 연구 방법이 야간에서의 자율주행에서 다양한 단점 및 문제들을 해결하고 사고를 줄이는 방법에 기여할 것으로 사료된다.

• 정보교육학회논문지
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• 제26권6호
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• pp.567-577
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• 2022

2022 개정 초등학교 교육과정에서 디지털 소양이 강조되면서 인공지능 교육과 소프트웨어 교육에 관심이 높아지고 있다. 초등학교에서 정보 교육을 위해 할당된 수업 시수는 34시간뿐이어서, 학생들의 디지털 소양을 기르는 데 한계가 많다. 따라서 인공지능과 소프트웨어 교육을 위한 수업 시수를 확보하려면 다른 교과와 정보 교육이 융합하는 형태로 이루어져야 한다. 본 연구에서는 S-PUMA 교수법을 활용한 글 읽기 교육이 초등학생의 문학적 상상력에 어떤 영향을 미치는지는 분석하였다. 이 연구를 위해 초등학교 6학년 2개 반을 선정하여 실험 집단과 통제 집단으로 구분하고, 실험집단에만 5차시에 걸쳐 S-PUMA 교수법에 따라 글 읽기 교육을 진행하였다. 그 결과, S-PUMA 교수법을 활용한 글 읽기 교육이 문학적 상상력과 컴퓨팅 사고력을 향상시킨 것으로 분석되었다. 다만, 문학적 상상력의 하위 영역인 창조적 상상력은 모든 집단에서 향상되었기에 S-PUMA 교수법에 의한 효과인지, 교육 내용에 따른 자연적인 효과인지 추가적인 연구가 필요하다.

• 대한영양사협회학술지
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• 제4권1호
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• pp.20-29
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• 1998

The purpose of this study was to investigate the effect of food habits on blood components level(blood glucose, uric acid, hemoglobin, some lipids levels) and health condition in Taejon. The study was conducted with 250 subjects (male 130, female120) who visited in a general hospital from May to June in 1997. Questionaires were used for food habits. The data were analyzed by using $x^2$-test, t-test, ANOVA and multiple range test. Results were summerized s follow : mean of Broca Index were 110.0 $\pm$13.7% in male, 110.6$\pm$16.6% in female. Mean values of systolic blood pressure and diastolic blood pressure were 130.9$\pm$17.6mmHg, 76.2$\pm$12.6mmHg, respectively. The systolic blood pressure was significantly higher in man than woman, Mean serum total cholesterol, LDL-cholesterol, and HDL-cholesterol and triglyceride levels were 202.8$\pm$40.2, 121.1$\pm$35.5, 50.3$\pm$12.9, 157.1$\pm$112.6mg/dl, respectively. Triglyceride level was significantly higher in man than woman. But HDL-cholesterol was significantly lower in man than woman. And also, the value of LPH and AI were higher in man. So Man has more risk of atherogenesis than woman. Mean values of blood sugar, uric acid and hemoglobin was 102.7$\pm$1.36mg/dl and 14.1$\pm$1.56g/dl were higher in man than woman except blood sugar. Food habit of woman were better than it of man. The levels of education and income did not affect to food habit score. The most problem of habits were intake of salty food and lack of exercise. The intake of nutrients were higher as food habit score was higher. Intakes of energy, Ca, vitamin A and vitamin $B^1$ were lower than RDA's of nutrients in bad food habit group. This result did not show that blood components level and health condition were significantly different by food habits. But Broca Index and triglyceride levels were higher in bad food habit group than other groups, but not statistically significant. By this result, it is more needed food habit education to man and young people. The education of food habits will include the real methods of weight control, low intake of salt and exercise to bad food habit group.

• 수산해양기술연구
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• 제22권4호
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• pp.1-20
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• 1986

Physical, chemical and biological surveys on Nakdong River estuary were made from October, 1985 to September, 1986. 1. For all the seasons except summer, the sea surface temperature in northwest area of the line which linked from Seo Island to Jisim Island was I-2$^{\circ}$C lower than in southeast area, but in summer the sea surface temperature in northwest area was I-2$^{\circ}$C higher than in southeast area. On the contrary, bottom temperature of coastal area was 1$^{\circ}$C higher than that of oceanic area except winter. 2. Surface salinity in summer and fall has minimum value of 1. 9%0 and maximum value of 32.9%0. This large variation was caused by the runoff of the Nakdong River. Effect of less saline Nakdong River water in northwest area of the line which linked from Seo Island to Jisim Island was greater than in southeast area. A strong current rip always formed near this line. 3. The yellowish-green colored zone was observed in the Nakdong River estuary throughout the year by influence of river discharge. The characteristics of the water quality in the zone have shown that the water color was grade 7 by the Forel water-color meter, transparency was less than 4 m, and concentration of suspended solids was more than 5 mg/1. This water body was in the state of eutrophication in terms of chlorophyll-a and inorganic nitrogen concentration during summer season. 4. During the study period, total 276 taxa were identified. Most of them were diatoms and dinoflagellates which consisted of 97.5%. The component ratio of the above two groups was 84.4% and 13.1 % respectively. Diatoms were plentiful in December and dinoflagellates in July. Dominant species were Nitzschia seriata in October, Thalassiosira rotula in December, Skeletoncma costatum in April, and Nitzschia longissima in July. 5. A total of 47 zooplankton taxa was identified from the samples collected. Copepods were numerically the most important components of zooplankton communities in the study area. The domir:ant copepod species were Paracalanus parvus, Acartia clausi and Temora turbinata. Noctiluca scintillans was the next important component. The other zooplankton with minor abundance were Cladocera. Sagitta spp., Cnidaria, Mysidacea, Lucifer spp. and Amphipoda. 6. During the study period, fishes from 47 families and 87 species were sampled in th~ study area. The four most abundant fish species were Rep~mucen//'s valencicnnei, Leiognathus n~cha!is, Amblychaeturicllthys hexanema and Sardirel/a zun:zsi. The fish species of the secondary importance in abundance were Cynoglossus joyneri, Sillago sihama, Engra~lis japonicus, Encdrias nebulos'l, Acanthogobius flavimanus, Trichiurus lepturus, LiParis tanai/ai, Cynagloss//'s interruptus, Aj)ogon line:z!us, Thrissz la 1l.'1la!ensis, and Limanda yokohamac.

• 가정과삶의질연구
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• 제24권5호
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• pp.69-87
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• 2006

This article attempts to explore how the women retirees under study were able to continue work until retirement. This study used life histories, especially focusing on daily working lives, and uncovered a number of key issues through in-depth interviews. The main results are as follows: Firstly, the women retirees examined here had been raised as highly educated people, and their strong educational background was a base component for them to have relatively secure careers. Their parents had also supported practically the women retirees during their working lives. In addition, the women retirees had to can out the roles of 'provider' for their original families, procreation families or in-law families, even though they were not given the recognized roles of provider. Secondly, the women retirees had a private infra system to support them with housework and child care. In addition, because they were financially able to employ housemaids, the women retirees did not experience conflicts with their husbands, who took on a neo-traditional sex role. Finally, thanks to relatively good working conditions such as having vacations and being able to come to and leave the office on time, the women retirees were able to continue work until retirement no mean feat in a society which openly practiced gender discrimination.

• 한국식품과학회지
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• 제31권1호
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• pp.252-256
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• 1999

한우육의 사태(M. Semitendinosus)를 대상으로 감마선 조사선량(0, 1, 3, 5, 10 kGy)에 따른 지질성분과 항산화 효소 활성도 및 ${\alpha}-tocopherol$ 함량의 변화를 측정하였다. 총 콜레스테롤, LDL-콜레스테롤, HDL-콜레스테롤 및 중성지질 함량에서는 비조사군과 조사군간에 유의적인 차이를 보이지 않았다(p>0.05). 항산화 효소의 활성에서 GST, catalase, SOD 역시 비조사군과 조사군간에 유의적인 차이를 보이지 않았다(p>0.05). 한편, 등심부위의 ${\alpha}-tocopherol$ 함량은 감마선 조사선량이 증가함에 따라 유의적으로 감소되었다(P<0.05).

• The Journal of Advanced Prosthodontics
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• 제12권6호
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• pp.369-375
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• 2020

PURPOSE. This study evaluated the availability of multi-directionally forged (MDF) titanium (Ti) as a component of removable partial dentures (RPDs). MDF-Ti remarkably improved the mechanical properties of RPDs due to its ultrafine-grained structure. MATERIALS AND METHODS. The wear resistance, plaque adhesion, and machinability of MDF-Ti were tested. As controls, commercially pure (CP) titanium was used for wear, plaque adhesion, and machinability tests. For wear resistance, the volume losses of the titanium teeth before and after wear tests were evaluated. Plaque adhesion was evaluated by the assay of Streptococcus mutans. In the machinability test, samples were cut and ground by a steel fissure bur and carborundum (SiC) point. An unpaired t-test was employed for the analysis of the significant differences between MDF-Ti and the control in the results for each test. RESULTS. Wear resistance and plaque adherence of MDF-Ti similar to those of CP-Ti (P>.05) were indicated. MDF-Ti exhibited significantly larger volume loss than CP-Ti in all conditions except 100/30,000 g/rpm in machinability tests (P<.05). CONCLUSION. Although the wear resistance and plaque adherence of MDF-Ti were comparable to those of controls, MDF-Ti showed better machinability than did CP-Ti. MDF-Ti could be used as a framework material for RPDs.

• 한국IT서비스학회지
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• 제19권6호
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• pp.145-159
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• 2020

Because of the recent development of information and communication technology, companies are exposed to various media such as blogs, social media, and YouTube. In particular, exposed news affects the company's reputation. So, while positive news can improve corporate value, negative news can lead to financial losses for the company. In this study, we redefine corporate reputation as social responsibility, vision and leadership, financial performance, products and services through existing literature, and conducted an AHP survey with a total of four components to calculate the weight of each factor. As a result of the calculation, the proportion of financial performance was the highest at 0.41, and products and services, vision and leadership, and social responsibility were the lowest. In addition, in order to measure the reputation of a company, it is classified as a component that defines online news using the LDA technique. In addition, through sentiment analysis, an index for each corporate reputation factor was derived, and the reputation index was calculated by combining it with the AHP analysis result, and Spearman ranking correlation analysis was performed to secure the validity of the research results. Therefore, the significance of this study is that the definition and importance of the constituent factors can contribute to the future planning and development direction of the company, and also contribute to the derivation of the corporate reputation index. This study is significant in that a new analysis methodology that applied AHP analysis results to sentiment analysis was suggested.