• 제목/요약/키워드: method of research

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균형 잡힌 데이터 증강 기반 영상 감정 분류에 관한 연구 (A Study on Visual Emotion Classification using Balanced Data Augmentation)

  • 정치윤;김무섭
    • 한국멀티미디어학회논문지
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    • 제24권7호
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    • pp.880-889
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    • 2021
  • In everyday life, recognizing people's emotions from their frames is essential and is a popular research domain in the area of computer vision. Visual emotion has a severe class imbalance in which most of the data are distributed in specific categories. The existing methods do not consider class imbalance and used accuracy as the performance metric, which is not suitable for evaluating the performance of the imbalanced dataset. Therefore, we proposed a method for recognizing visual emotion using balanced data augmentation to address the class imbalance. The proposed method generates a balanced dataset by adopting the random over-sampling and image transformation methods. Also, the proposed method uses the Focal loss as a loss function, which can mitigate the class imbalance by down weighting the well-classified samples. EfficientNet, which is the state-of-the-art method for image classification is used to recognize visual emotion. We compare the performance of the proposed method with that of conventional methods by using a public dataset. The experimental results show that the proposed method increases the F1 score by 40% compared with the method without data augmentation, mitigating class imbalance without loss of classification accuracy.

천연소재 담배 필터 적용 방법 (The Natural Ingredient Application Method of Cigarette Filter)

  • 김민규;여운형;김수호;오경환;진용숙;황의일
    • 한국연초학회지
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    • 제35권1호
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    • pp.13-19
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    • 2013
  • The natural ingredient has been utilized variety of the food and medicine. The aromatherapy well known prevent disease and healthy promotion using the essential oil derived extracted plants. In this work, natural ingredient include herb granulated for application of tobacco filter. That used by granulation using fluidized bed granulator(top-spray, bottom-spray and tangential-spray) and wet granule method. According to ingredient can used granulating method selectivity. So, we used fluid-bed granulator and wet granule method. Grapefruit extract coated sugar particle using the bottom-spray method and red ginseng granule granulated red ginseng powder using the tangential-spray method in a fluidized bed. Then, these granules applied the tobacco filter after due consideration add amount and operation efficiency. As a result, wet granule was loaded dual filter because that similarity carbon granule. And it was fitted in added 3mg/mm, per tip in the tobacco end part. Another type, fuidized bed granules was filled cavity filter because it has high hardness, sphere shape.

시료 중 잔류 항생제 분석 방법: IV. EPA method 1694와 비교 가능한 기기 분석 방법 (Determination of Veterinary Antibiotic Residues: IV. Comparable Analytical Methods with EPA Methods 1694_A Review)

  • 김찬식;류홍덕;정유진;김용석;류덕희
    • 한국물환경학회지
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    • 제32권6호
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    • pp.670-699
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    • 2016
  • In this study, 16 antibiotics were selected from among the top 30 veterinary antibiotics sold in South Korea in 2014, as well as from among the pharmaceuticals targeted by EPA method 1694, in order to review analytical methods for the detection of trace levels of antibiotics in environmental samples: surface water, soils, animal origin foods, and manures. LC-MS/MS was heavily used. In the chromatography for the detection of the selected antibiotics, the $C_{18}$ column was mostly used at the temperature of $30{\sim}40^{\circ}C$. Water and methanol/acetonitrile were commonly chosen as a nonpolar and a polar mobile phase, respectively. Gradient elution was applied to separate multiclass antibiotics. Volatile additives, such as formic acid, acetic acid, and ammonium acetate were mixed with the mobile phase to improve the ionization efficiency of analytes and the sensitivity in MS detection. Electrospray ionization (ESI) was widely used in the LC-MS/MS and positive ionization was preferred to determine the selected antibiotics. A protonated $[M+H]^+$ molecule was selected as a precursor ion, and its two transitions were analyzed, one for quantitative measurement and the other for confirmation. This study reviewed linearity of the calibration curve, recovery, repeatability, method detection limits (MDLs), and method quantification limits (MQLs) for each target compound used to validate the developed analytical methods.

유류오염토양 중 다환방향족탄화수소류(PAHs) 분석방법 연구 - US EPA 16종 PAHs를 중심으로 (Analytical Method of Polycyclic Aromatic Hydrocarbons (PAHs) in Petroleum Contaminated Soils - Focused on the 16 US EPA Priority PAHs)

  • 김지영;김동호;김태승;한진석;이재영;노회정
    • 한국지하수토양환경학회지:지하수토양환경
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    • 제17권5호
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    • pp.20-30
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    • 2012
  • In case of analyzing PAHs (EPA 16 compounds) in oil-contaminated soils, the lump of peaks may occur because of the aliphatic and polar compounds in oil. This phenomenon is due to the lower accuracy of the analysis. To solve this problem, evaluation of application of silicagel-alumina multi-layer fraction was performed using standard substances and oil-contaminated soils. As a result of application of silicagel-alumina multi-layer fraction cleanup method using standard substances, recovery rates of surrogate standards (5 compounds including Naphthalene-d8) were 83~100% and those of target standards were 75~129%. These were to meet the target values (60~130%) in this study. When used 4% water-silicagel column analyze PAHs in oil-contaminated soils, Some problems were generated for quantitative analysis of PAHs; concentration of PAHs was underestimated due to an upward baseline of internal standard (recovery rate: less than 60%) and overestimated by the lump of peaks which were not purified (the biggest recovery rate: more than 400%). On the other hand, in case of silicagel-alumina multi-layer fraction cleanup method, recovery rate of surrogate standards were 61~101.6%. Therefore this cleanup method was considered a valid method to improve accuracy of analysis of PAHs in oil-contaminated soils.

Improvement on optimal design of dynamic absorber for enhancing seismic performance of nuclear piping using adaptive Kriging method

  • Kwag, Shinyoung;Eem, Seunghyun;Kwak, Jinsung;Lee, Hwanho;Oh, Jinho;Koo, Gyeong-Hoi
    • Nuclear Engineering and Technology
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    • 제54권5호
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    • pp.1712-1725
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    • 2022
  • For improving the seismic performance of the nuclear power plant (NPP) piping system, attempts have been made to apply a dynamic absorber (DA). However, the current piping DA design method is limited because it cannot provide the globally optimum values for the target design seismic loading. Therefore, this study proposes a seismic time history analysis-based DA optimal design method for piping. To this end, the Kriging approach is introduced to reduce the numerical cost required for seismic time history analyses. The appropriate design of the experiment method is used to increase the efficiency in securing response data. A gradient-based method is used to efficiently deal with the multi-dimensional unconstrained optimization problem of the DA optimal design. As a result, the proposed method showed an excellent response reduction effect in several responses compared to other optimal design methods. The proposed method showed that the average response reduction rate was about 9% less at the maximum acceleration, about 5% less at the maximum value of the response spectrum, about 9% less at the maximum relative displacement, and about 4% less at the maximum combined stress compared to existing optimal design methods. Therefore, the proposed method enables an effective optimal DA design method for mitigating seismic response in NPP piping in the future.

Measurement of the Apparent Density of Shred and Void Fraction in a Tobacco Column

  • Oh, In-Hyeog;Jeh, Byong-Kwon;Ra, Do-Young;Kwak, Dae-Keun;Kim, Byeoung-Ku;Jo, Si-Hyung;Rhee, Moon-Soo
    • 한국연초학회지
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    • 제29권1호
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    • pp.23-29
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    • 2007
  • The measurement of physical properties such as apparent density and void fraction of tobacco materials, which is so bulky, is a main theme with regard to tobacco process, quality control, cigarette combustion and smoke generation. Except Solution Impregnation Method, there was no alternative method for measuring those properties in the porous material so far. However, experimental processes of that method are so complicated as to cost much time and labor, the main solution such as mercury to apply to the method is usually very hazard. Therefore, we had developed a new method to determine them easily in our other paper by the mathematical equations derived from the Ergun equation for the purpose of it, and then already evaluated our method through applying some basic data from Muramatsu et at. (1979) with regard to our developed equations. Then, we found our method best fit to experimental one (Oh et al., 2001). In this study we tried to establish our method to conveniently determine those physical properties. Especially, we have focused on the development the easy way to measure surface area and the volume of single shred in a tobacco column. As a result of that, we found that the computer image analyzer was best fit for it. Then, we have finally determined apparent density and void fraction for our domestic tobacco shred.

국내.외 환경교육 논문 분석을 통한 연구 경향 비교 (Comparison of Korean and International Environmental Education Trends through Research Synthesis)

  • 신동희;이지희
    • 한국환경교육학회지:환경교육
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    • 제22권4호
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    • pp.111-133
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    • 2009
  • To understand the research trend of environmental education(EE) during last two decades, we analyzed a total of 801 research papers published from 1990 to 2008, 418 research papers from "Hwankyungkyouk" and 393 research papers from "The Journal of Environmental Education(JEE)", respectively. The majority of the authors in both journals majored in EE, followed by authors of science education major in "Hwankyungkyouk" and authors of social science major in JEE. In both journals, more researches were data-collected by quantitative method rather than qualitative method. In particular, the ratio of researches by qualitative method have been dramatically increased since the mid 1990s. The significance test was less used in Korean EE researches than those in JEE. In both journals, more EE researches for elementary and secondary school students were accomplished, which tended to be more salient in Korea. The result of the analysis of 119 EE programs in both journals proposed that EE program needs to be developed more diversely in content as well as in educational method.

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A Study on the Estimation of the Value of Tourists' WTP by Payment Method: Focusing on the Gangwon State

  • Hee-Won Yang;Chang-Young Jeon;O-Young Kwon
    • 아태비즈니스연구
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    • 제14권3호
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    • pp.251-269
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    • 2023
  • Purpose - This study estimated the value of tourists' willingness to pay (WTP) to develop and promote regional tourism and minimize external effects using the contingent valuation method (CVM). Design/methodology/approach - To reduce exaggeration bias, a major issue of CVM, a pilot survey was conducted to categorize bid value. Additionally, the payment method was divided into a tourism fund and tourism taxes, and the respondents' answers were reaffirmed in two stages. Findings - As a result of the analysis, the tourists' WTP was estimated to be 5,132 KRW (3.60 USD) for the tourism fund and 1,036 KRW (0.73 USD) for tourism taxes. Research implications or Originality - The results of this study provide implications for securing financial resources and establishing policies in Gangwon province, which promotes special self-governing.

두 개의 하이드로폰을 이용한 수중 음원 방향각 기반의 2차원 위치 인식 기법 (Two dimensional SLAM based on Directional Angles of Underwater Acoustic Sources using Two Hydrophone)

  • 최진우;이영준;최현택
    • 로봇학회논문지
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    • 제11권3호
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    • pp.146-155
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    • 2016
  • Localization of underwater vehicle is essential to use underwater robotic systems for various applications effectively. For this purpose, this paper presents a method of two-dimensional SLAM for underwater vehicles equipped with two hydrophones. The proposed method uses directional angles for underwater acoustic sources. A target signal transmitted from acoustic source is extracted using band-pass filters. Then, directional angles are estimated based on Bayesian process with generalized cross-correlation. The acquired angles are used as measurements for EKF-SLAM to estimate both vehicle location and locations of acoustic sources. Through these processes, the proposed method provides reliable estimation for two dimensional locations of underwater vehicles. Experimental results demonstrate the performance of the proposed method in a real sea environment.

Roughness Measurement Performance Obtained with Optical Interferometry and Stylus Method

  • Rhee Hyug-Gyo;Lee Yun-Woo;Lee In-Won;Vorburger Theodore V.
    • Journal of the Optical Society of Korea
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    • 제10권1호
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    • pp.48-54
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    • 2006
  • White-light scanning interferometry (WLI) and phase shifting interferometry (PSI) are increasingly used for surface topography measurements, particularly for areal measurements. In this paper, we compare surface profiling results obtained from above two optical methods with those obtained from stylus instruments. For moderately rough surfaces ($Ra{\approx}500\;nm$), roughness measurements obtained with WLI and the stylus method seem to provide close agreement on the same roughness samples. For surface roughness measurements in the 50 nm to 300 nm range of Ra, discrepancies between WLI and the stylus method are observed. In some cases the discrepancy is as large as 109% of the value obtained with the stylus method. By contrast, the PSI results are in good agreement with those of the stylus technique.