• Title/Summary/Keyword: 자동상관계

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Development of an Automatic Monitoring System for Ultrasound Signals Using Artificial Intelligence and Convolutional Neural Networks (인공지능을 활용한 초음파 신호와 합성곱 신경망 기반 자동 적조 모니터링 시스템)

  • Daehun Kim;Hyeon-Ju Jeon;O-Joun Lee;Hae Gyun Lim
    • Proceedings of the Korea Information Processing Society Conference
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    • 2023.11a
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    • pp.662-664
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    • 2023
  • 해양 식물플랑크톤의 성장은 유해적인 적조를 유발할 수 있으며, 이는 여러 국가의 생태계에 피해를 주는 상황이다. 적조를 모니터링하는 것은 식물플랑크톤 미생물의 증가를 예방하고 통제하기 위해 중요하다. 그러나 현재의 적조 모니터링 기술은 날씨, 시간 제약 및 실시간 모니터링에 대한 어려움으로 인해 측정 정확도에 영향을 미치는 한계가 있다. 본 연구는 특히 적조 발생을 감지하기 위한 목적으로 개발된 자동 실시간 모니터링 시스템의 성공적인 개발을 보여준다. 개발한 시스템은 음향 반사파 데이터 처리를 통해 합성곱 신경망(Convolutional neural networks, CNN)을 활용하여 식물플랑크톤 농도를 정확하게 구별할 수 있다. 특히, 이 CNN 모델은 음향 신호의 변환된 주파수 스펙트럼과 Cochlodinium polykrikoides (C. polykrikoides)의 농도 간의 상관 관계를 수립하는 데 뛰어난 효과를 나타냈다. 이 CNN 은 C. polykrikoides 를 감지하는 데 0.90 의 정확도를 보여준다. 이러한 모니터링과 CNN 분류의 활용은 실시간 측정의 중요한 잠재력을 보여주며, 추가적인 절차가 필요 없는 자동 모니터링 시스템을 구축할 수 있을 것으로 예상된다.

Forecast of Areal Average Rainfall Using Radiosonde Data and Neural Networks (상층기상자료와 신경망기법을 이용한 면적강우 예측)

  • Kim Gwang-Seob
    • Journal of Korea Water Resources Association
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    • v.39 no.8 s.169
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    • pp.717-726
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    • 2006
  • In this study, we developed a rainfall forecasting model using data from radiosonde and rain gauge network and neural networks. The primary hypothesis is that if we can consider the moving direction of the rain generating weather system in forecasting rainfall, we can get more accurate results. We assume that the moving direction of the rain generating weather system is same as the wind direction at 700mb which is measured at radiosonde networks. Neural networks are consisted of 8 different modules according to 8 different wind directions. The model was verified using 350 AWS data and Pohang radiosonde data. Correlation coefficient is improved from 0.41 to 0.73 and skill score is 0.35. Statistical performance measures of the Quantitative Precipitation Forecast (QPF) model show improved output compared to that of rainfall forecasting model using only AWS data.

Evaluation of Precipitation Variability using Grid-based Rainfall Data Based on Satellite Image (위성영상 기반 격자형 강우자료를 활용한 강수량 변동성 평가)

  • Park, Gwang-Su;Nam, Won-Ho;Mun, Young-Sik;Yang, Mi-Hye;Lee, Hee-Jin
    • Proceedings of the Korea Water Resources Association Conference
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    • 2022.05a
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    • pp.330-330
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    • 2022
  • 우리나라에서 발생하는 기상 재해 현상은 주로 태풍, 집중호우, 장마 등 인명 및 경제적인 피해가 크며, 단기간에 국지적으로 나타난다. 현재 재해 감시 및 예보는 주로 종관기상관측체계를 이용하고 있다. 하지만, 우리나라의 복잡한 지형, 인구 밀집 지형, 관측 시기가 일정하지 않은 지형과 같은 조건에서 미계측 자료 및 지역이 다수 존재 때문에 강수의 공간 분포와 강도에 대한 정밀한 정보를 제공하지 못하는 실정이다. 최근 광범위한 관측영역과 공간 분해능의 개선, 자료추출 알고리즘의 개발로 전세계적으로 위성영상 기반 기상관측 자료의 활용성이 증대되고 있다. 본 연구에서는 한반도 지역의 지상 관측데이터와 전지구 격자형 위성 강우자료를 비교하여 한반도의 적용성을 분석하고자 한다. 다양한 위성영상 기반 기상자료인 Climate Hazards Groups InfraRed Precipitation with Station (CHIRPS), Precipitation Estimation From Remotely Sensed Information Using Artificial Neural Networks-Climate Data Record (PERSIANN-CDR), Global Precipitation Climatology Centre (GPCC), Precipitation Estimation From Remotely Sensed Information Using Artificial Neural Networks-Cloud Classification System (PERSIANN-CCS) 4개의 강우위성영상을 수집하여, 1991년부터 2020년까지 30년 데이터를 활용하였다. 강수량 변동성 비교를 위하여 기상청의 종관기상관측장비 (Automated Synoptic Observation System, ASOS), 자동기상관측시설 (Automatic Weather System, AWS) 데이터와 상관 분석을 수행하고, 강우위성영상의 국내 적합성을 판단하고자 한다.

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Comparison of Batch Assay and Random Assay Using Automatic Dispenser in Radioimmunoassay (핵의학 체외 검사에서 자동분주기를 이용한 Random Assay 가능성평가)

  • Moon, Seung-Hwan;Lee, Ho-Young;Shin, Sun-Young;Min, Gyeong-Sun;Lee, Hyun-Joo;Jang, Su-Jin;Kang, Ji-Yeon;Lee, Dong-Soo;Chung, June-Key;Lee, Myung-Chul
    • Nuclear Medicine and Molecular Imaging
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    • v.43 no.4
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    • pp.323-329
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    • 2009
  • Purpose: Radioimmunoassay (RIA) was usually performed by the batch assay. To improve the efficiency of RIA without increase of the cost and time, random assay could be a choice. We investigated the possibility of the random assay using automatic dispenser by assessing the agreement between batch assay and random assay. Materials and Methods: The experiments were performed with four items; Triiodothyronine (T3), free thyroxine (fT4), Prostate specific antigen (PSA), Carcinoembryonic antigen (CEA). In each item, the sera of twenty patients, the standard, and the control samples were used. The measurements were done 4 times with 3 hour time intervals by random assay and batch assay. The coefficient of variation (CV) of the standard samples and patients' data in T3, fT4, PSA, and CEA were assessed. ICC (Intraclass correlation coefficient) and coefficient of correlation were measured to assessing the agreement between two methods. Results: The CVs (%) of T3, fT4, PSA, and CEA measured by batch assay were 3.2$\pm$1.7%, 3.9$\pm$2.1%, 7.1$\pm$6.2%, 11.2$\pm$7.2%. The CVs by random assay were 2.1$\pm$1.7%, 4.8$\pm$3.1%, 3.6$\pm$4.8%, and 7.4$\pm$6.2%. The ICC between the batch assay and random assay were 0.9968 (T3), 0.9973 (fT4), 0.9996 (PSA), and 0.9901 (CEA). The coefficient of correlation between the batch assay and random assay were 0.9924(T3), 0.9974 (fT4), 0.9994 (PSA), and 0.9989 (CEA) (p<0.05). Conclusion: The results of random assay showed strong agreement with the batch assay in a day. These results suggest that random assay using automatic dispenser could be used in radioimmunoassay.

Analysis of Phenological Changes by Phenocams on Some Major Species Distributed in Wetland and Forest Ecosystems in Korea (Phenocam을 활용한 국내 습지 및 산림생태계 대표 수종의 계절적 변화 분석)

  • Minki Hong;Hyohyemi Lee;Jeong-Soo Park
    • Ecology and Resilient Infrastructure
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    • v.10 no.4
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    • pp.226-236
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    • 2023
  • As climate change intensifies, the importance of studying plant phenology has increased, leading to a surge in research employing automated video recording devices like Phenocams. In this study, using the Phenocams operated by the National Institute of Ecology, we examined the trends in plant phenological changes across diverse ecosystem types in South Korea and analyzed their correlations with climate factors. The patterns of plant phenological changes varied by region and tree species. Pinus thunbergii and Pinus densiflora typically show an overall increase in their growth period, positively correlating with temperatures and precipitation during winter. However, uniquely, for Abies koreana on Hallasan Mt., a higher amount of precipitation in August leads to an earlier end of season (eos), and the correlation analysis with the recent phenomenon of dying A. Koreana seems necessary. beyond the analysis, solutions for handling missing data issues during the data collection process were proposed. Furthermore, to expand future research scope and encompass diverse ecosystem types, a suggestion to combine Phenocam research with satellite observations was presented.

Construction of X-band automatic radar scatterometer measurement system and monitoring of rice growth (X-밴드 레이더 산란계 자동 측정시스템 구축과 벼 생육 모니터링)

  • Kim, Yi-Hyun;Hong, Suk-Young;Lee, Hoon-Yol
    • Korean Journal of Soil Science and Fertilizer
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    • v.43 no.3
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    • pp.374-383
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    • 2010
  • Microwave radar can penetrate cloud cover regardless of weather conditions and can be used day and night. Especially a ground-based polarimetric scatterometer has advantages of monitoring crop conditions continuously with full polarization and different frequencies. Kim et al. (2009) have measured backscattering coefficients of paddy rice using L-, C-, X-band scatterometer system with full polarization and various angles during the rice growth period and have revealed the necessity of near-continuous automatic measurement to eliminate the difficulties, inaccuracy and sparseness of data acquisitions arising from manual operation of the system. In this study, we constructed an X-band automatic scatterometer system, analyzed scattering characteristics of paddy rice from X-band scatterometer data and estimated rice growth parameter using backscattering coefficients in X-band. The system was installed inside a shelter in an experimental paddy field at the National Academy of Agricultural Science (NAAS) before rice transplanting. The scatterometer system consists of X-band antennas, HP8720D vector network analyzer, RF cables and personal computer that controls frequency, polarization and data storage. This system using automatically measures fully-polarimetric backscattering coefficients of rice crop every 10 minutes. The backscattering coefficients were calculated from the measured data at a fixed incidence angle of $45^{\circ}$ and with full polarization (HH, VV, HV, VH) by applying the radar equation and compared with rice growth data such as plant height, stem number, fresh dry weight and Leaf Area Index (LAI) that were collected at the same time of each rice growth parameter. We examined the temporal behaviour of the backscattering coefficients of the rice crop at X-band during rice growth period. The HH-, VV-polarization backscattering coefficients steadily increased toward panicle initiation stage, thereafter decreased and again increased in early-September. We analyzed the relationships between backscattering coefficients in X-band and plant parameters and predicted the rice growth parameters using backscattering coefficients. It was confirmed that X-band is sensitive to grain maturity at near harvesting season.

Assessment of Antioxidant Activity and Residue Level of Phenolic Antioxidants in Autoxidation of Linoleic Acid (리놀레인산 자동산화에 미치는 페놀계 산화방지제의 활성 및 잔존량 평가)

  • Choi, Seung-Hyun;Kim, Jae-Min;Choi, Sun-Il;Jung, Tae-Dong;Oh, Ji-Won;Cho, Bong-Yeon;Lee, Jin-Ha;Lee, Ok-Hwan
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.7
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    • pp.1065-1070
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    • 2016
  • This study assessed the antioxidant activity and residue level of phenolic antioxidants in autoxidation of linoleic acid. The antioxidant activity of phenolic antioxidants was measured based on peroxide value of linoleic acid at $50^{\circ}C$ for 8 days. We further evaluated the residue level of phenolic antioxidants in the autoxidation period by HPLC-UV. The residue level of antioxidants changed with time starting on day 0 (100%) and was determined by 100-remaining of antioxidants (%). Our results showed that peroxide values ranged from 0.33 to 10.18 meq/kg in propyl gallate, from 0.67 to 11.01 meq/kg in dodecyl gallate, from 0.01 to 10.34 meq/kg in octyl gallate, from 0.01 to 4.17 meq/kg in butylated hydroxytoluene (BHT), from 1.00 to 5.85 meq/kg in butylated hydroxyanisole (BHA), from 0.33 to 4.18 meq/kg in 2,4,5-trihydroxybutyrophenone, and from 1.00 to 11.01 meq/kg in tert-butylhydroquinone (TBHQ). Among the residue levels of antioxidants, on day 8, BHT showed the highest level while TBHQ showed the lowest. BHT showed the highest correlation coefficient, whereas BHA showed the lowest. This study proves that the residual level of phenolic antioxidants has a good correlation with the degree of autoxidation in linoleic acid.

Time Series Forecasting on Car Accidents in Korea Using Auto-Regressive Integrated Moving Average Model (자동 회귀 통합 이동 평균 모델 적용을 통한 한국의 자동차 사고에 대한 시계열 예측)

  • Shin, Hyunkyung
    • Journal of Convergence for Information Technology
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    • v.9 no.12
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    • pp.54-61
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    • 2019
  • Recently, IITS (intelligent integrated transportation system) has been important topic in Smart City related industry. As a main objective of IITS, prevention of traffic jam (due to car accidents) has been attempted with help of advanced sensor and communication technologies. Studies show that car accident has certain correlation with some factors including characteristics of location, weather, driver's behavior, and time of day. We concentrate our study on observing auto correlativity of car accidents in terms of time of day. In this paper, we performed the ARIMA tests including ADF (augmented Dickey-Fuller) to check the three factors determining auto-regressive, stationarity, and lag order. Summary on forecasting of hourly car crash counts is presented, we show that the traffic accident data obtained in Korea can be applied to ARIMA model and present a result that traffic accidents in Korea have property of being recurrent daily basis.

Discharge estimation using surface velocity and index velocity method (표면유속과 지표유속법을 이용한 유량산정)

  • Lee, Sin Jae;Choi, Hong Yoon;Lee, Dae Young
    • Proceedings of the Korea Water Resources Association Conference
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    • 2018.05a
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    • pp.273-273
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    • 2018
  • 하천유량을 산정하는 전통적인 방법은 수위-유량관계(stage-discharge relation)를 이용하는 것이며, 최근에는 하천특성에 따라 연속적으로 유속을 직접 측정하고 지표유속법(index velocity method) 또는 유속분포법(velocity profile method)을 이용하는 방법도 적용되고 있다. 연속으로 유속을 측정하는 방법에는 전자파 또는 영상이미지를 이용하여 표면유속을 측정하는 방법과 수중에 초음파 유속계를 설치하여 수중의 유속을 측정하는 방법이 있으며, 국내에서는 초음파 유속계를 이용하는 방법이 주로 활용되고 있다. 본 연구에서는 전자파표면유속계(MU2720)로 측정된 표면유속과 지표유속법을 이용하여 하천유량 산정방법을 검토하였다. 본 연구는 홍천강의 홍천군(반곡교)와 홍천군(홍천교), 한탄강의 철원군(한탄대교) 수위관측소에서 2016년도에 전자파표면유속계로 측정된 43개의 자료(평균유속 0.61~2.56m/s)를 이용하였다. 전자파표면유속계에 의한 유속측정은 한 지점에 고정하여 측정하지 않고 여러 개의 측선을 분할하여 표면유속을 측정하였으며, 단면 평균유속(Vm)과 가장 상관성이 높은 측선(지점)의 유속을 지표유속으로 하여 지표유속(vi)과 평균유속과의 관계식을 작성하고, 이를 통해 유량을 산정하였다. 여기서 평균유속은 전자파표면유속계로 측정한 유속을 이용하여 산정한 값이다. 그 결과 지표유속과 평균유속관계식의 결정계수($R^2$)는 0.9874~0.9976이었으며, 측정 평균유속과 지표유속관계식으로 산정된 평균유속과의 평균 편차율은 2.26~3.80%로 표면유속과 지표유속법을 이용한 유량산정 방법의 적정성을 확인할 수 있었다. 따라서 현재 국내에서 자동유량측정시스템에 초음파유속계만 상용화되고 있으나 향후에는 하천특성에 따라 전자파표면유속계를 이용하는 방법도 고려해 볼 필요가 있을 것으로 판단된다.

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A Study of Wet Process for High-durability Automobile leather (Automobile leather의 내구성 증진을 위한 Wet process 연구)

  • Shin, Eun-Chul;Lee, Sang-Chul;Kim, Won-Ju;Kang, Gun;Yun, Mi-Jung;Oh, Jung-Suk;Jeong, Ki-Yeon
    • Proceedings of the Korean Society of Dyers and Finishers Conference
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    • 2011.11a
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    • pp.53-53
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    • 2011
  • 자동차용 천연가죽 시트의 제조 공정에서 크롬과 비크롬 Metalic 탄닝제, 식물성 탄닝제, 신탄(Syntan) 및 가지제(Fatliuor) 등의 종류와 함량에 따른 인장강도, 신장율, 정하중 신율, 잔류줄음율 등을 측정하여 특정하중에 따른 콜라겐 섬유 조직의 영구변형율과의 상관관계를 비교 분석해본 결과, 크롬 및 비크롬계 탄닝제에 비해 식물성 탄닝제를 적용하였을 때 조직의 변형율이 적었으며, 리틴닝 공정에서 아크릴계, 레진계 및 단백질계 신탄을 혼합 적용하였을 때 가죽의 배(Belly)부위의 물성 균일화 효과가 우수하였으며, 음이온성 가지제 9%를 사용하여 가죽에 유연성을 부여함으로써 조직이 치밀하고 변형율이 감소되어 내구성이 우수한 결과를 나타내었다.

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