• Title/Summary/Keyword: long-term observation

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Application to Evaluation of Hydrologic Time Series Forecasting for Long-Term Runoff Simulation (장기유출모의를 위한 수문시계열 예측모형의 적용성 평가)

  • Yoon, Sun-Kwon;Ahn, Jae-Hyun;Kim, Jong-Suk;Moon, Young-Il
    • Journal of Korea Water Resources Association
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    • v.42 no.10
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    • pp.809-824
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    • 2009
  • Hydrological system forecasting, which is the short term runoff historical data during the limited period in dam site, is a conditional precedent of hydrological persistence by stochastic analysis. We have forecasted the monthly hydrological system from Andong dam basin data that is the rainfall, evaporation, and runoff, using the seasonal ARIMA (autoregressive integrated moving average) model. Also we have conducted long term runoff simulations through the forecasted results of TANK model and ARIMA+TANK model. The results of analysis have been concurred to the observation data, and it has been considered for application to possibility on the stochastic model for dam inflow forecasting. Thus, the method presented in this study suggests a help to water resource mid- and long-term strategy establishment to application for runoff simulations through the forecasting variables of hydrological time series on the relatively short holding runoff data in an object basins.

HIGH RESOLUTION SPECTROSCOPIC STUDY OF SYMBIOTIC STAR AG DRACONIS

  • KIM, SOO HYUN;YOON, TAE SEOG;OH, HYUNG-IL
    • Publications of The Korean Astronomical Society
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    • v.37 no.2
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    • pp.13-31
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    • 2022
  • We observed the symbiotic star AG Dra for a total of 61 nights between April 2004 and December 2021 using the 1.8-m telescope and the high-resolution Echelle spectrograph BOES at the Bohyunsan Optical Astronomy Observatory and obtained 355 frames of spectroscopic data to investigate the variations in its spectral lines. Overnight short-term and long-term changes in prominent emission lines are examined. No short-term changes are found in the line profiles. However, the peak intensity of the Hα emission line exhibits very small variation. In the long-term period, many emission lines including He I λ5875, λ6678, λ7065 and Fe II λ5018 are found to vary reflecting the symbiotic outburst activities. It is noted that He II λ4686 and Raman-scattered O VI λ6830, λ7088 are exceptions, where no significant variations are discernible. One of the noticeable lines is the λ5018 line. Its appearance and disappearance pattern are different from other emission lines, and the line is found to appear in outburst states. The Hα and Hβ lines remain very similar in our spectroscopic monitoring campaign.

The Disagreement of Discourse and Power Through the Experiences of Nursing for Caring of Long-term Hospitalized Patients (장기 입원환자 간호 갈등경험을 통해 본 담론 대립과 권력)

  • Kim, Hae Ok
    • Korean Journal of Adult Nursing
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    • v.19 no.3
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    • pp.495-507
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    • 2007
  • Purpose: This critical ethnography was performed to explore the experiences of nurses who are working with patients in an industrial disaster hospital. During the research process, I focused on the experiences of conflict in caring patients. Methods: Data for the study came from 13 informants with their corresponding patients through interview and observation from March 2002 to February 2004. The data was examined line by line; then compared and contrasted based on a critical discourse analysis. Results: Nurses' conflicts came from discrepancies of the world views from that of the patients. Such conflicts arose because of various issues as follows: Worker as an individual vs patients, nurse as young women vs the medical profession, hospital as an extended home vs health care setting, and hospitalization as a means to enhance work capacity vs a means of treatment. Conclusion: We need more study on the development of adaptive strategy for the nurses to overcome conflicts during their nursing career. Developing a nurses' and patient role intervention program is needed.

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Merits and Limitations of Microgenetic Method as a Means of Studying Developmental Change (아동 발달연구에 있어서 미시발생적 방법의 실과 허)

  • Jun, Myong Nam
    • Korean Journal of Child Studies
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    • v.22 no.1
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    • pp.97-107
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    • 2001
  • This study argues the nature of the microgenetic method in respect to child development research and explores its merits and limitations. The microgenetic method focuses on observations that span the entire period from the beginning of developmental change to the time it reaches a relatively stable state. This produces a high density of observations relative to the rate of change in the phenomenon. In this way, observed behavior may be used in intensive trial-by-trial analysis. The microgenetic method is superior to other methods in the possibilities for observing developmental changes as they occur, examining various aspects of change, detecting variability in behavior, and flexibility in application regardless of theoretical perspectives. Limitations of this method include reliability problems due to repeated observations, artificiality relative to the natural situation, inconsistency of short-and long-term change, and demands on children's motivation for participation in research.

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Photoelectric Observation of the Long-Period Eclipsing Binaries at Yonsei University Observatory

  • Nha, Il-Seong;Lee, Yong-Sam;Chun, Yong-Woo;Kim, Ho-Il;Kim, Young-Soo
    • Journal of Astronomy and Space Sciences
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    • v.3 no.1
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    • pp.1-13
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    • 1986
  • A long-term project(ten-year ; 1982-92) for the photoeletric observation in the UBV passbands of selected eclipsing binaries with P$\geq$10 days has initiated at Yonsei University Observatory using 40-cm and 61-cm reflectors. the instrumentatio used and the observation techniques and the reduction procedures applied to this investiagation are described. Out of 39 program stars, successful results have been obtained during our first two years for the 11 stars listed below, with the orbital period in days in the parenthesis, and the incomplete light curves of these stars are presented. SX Cas (36.57) AQ Cas (11.72) UU Cnc (96.71) RY Gem (9.30) V373 Cas (13.42) NY Cep (15.28) RX Cas (32.32) V396 Cas (15.28) ZZ Cnc (25.60) Zet Aur (982.2) Eps Aur (9885.) For the rest of the stars, the observations made in the first two years are not sufficient to attempt any meaning light curve construction ; some of the data are too fragmented and others show large scatter.

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Development of Ground-based GNSS Data Assimilation System for KIM and their Impacts (KIM을 위한 지상 기반 GNSS 자료 동화 체계 개발 및 효과)

  • Han, Hyun-Jun;Kang, Jeon-Ho;Kwon, In-Hyuk
    • Atmosphere
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    • v.32 no.3
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    • pp.191-206
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    • 2022
  • Assimilation trials were performed using the Korea Institute of Atmospheric Prediction Systems (KIAPS) Korea Integrated Model (KIM) semi-operational forecast system to assess the impact of ground-based Global Navigation Satellite System (GNSS) Zenith Total Delay (ZTD) on forecast. To use the optimal observation in data assimilation of KIM forecast system, in this study, the ZTD observation were pre-processed. It involves the bias correction using long term background of KIM, the quality control based on background and the thinning of ZTD data. Also, to give the effect of observation directly to data assimilation, the observation operator which include non-linear model, tangent linear model, adjoint model, and jacobian code was developed and verified. As a result, impact of ZTD observation in both analysis and forecast was neutral or slightly positive on most meteorological variables, but positive on geopotential height. In addition, ZTD observations contributed to the improvement on precipitation of KIM forecast, specially over 5 mm/day precipitation intensity.

Long-Term Efficacy of Anti-Tumor Necrosis Factor Agents in Pediatric Luminal Crohn's Disease: A Systematic Review of Real-World Evidence Studies

  • Rheenen, Hanna van;Rheenen, Patrick Ferry van
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.23 no.2
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    • pp.121-131
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    • 2020
  • Purpose: To determine the long-term efficacy of the anti-tumor necrosis factor (TNF) agents, infliximab (IFX) and adalimumab (ADA), in pediatric luminal Crohn's disease (CD) by performing a systematic literature review. Methods: An electronic search was performed in Medline, Embase, and the Cochrane Library from inception to September 26, 2019. Eligible studies were cohort studies with observation periods that exceeded 1 year. Studies that reported time-to-event analyses were included. Events were defined as discontinuation of anti-TNF therapy for secondary loss of response. We extracted the probabilities of continuing anti-TNF therapy 1, 2, and 3 years after initiation. Results: In total, 2,464 papers were screened, 94 were selected for full text review, and 13 studies (11 on IFX, 2 on ADA) met our eligibility criteria for inclusion. After 1 year, 83-97% of patients were still receiving IFX therapy. After 2 and 3 years the probability of continuing IFX therapy decreased to 67-91% and 61-85%, respectively. In total, 5 of the 11 studies subgrouped by concomitant medication consistently showed that the probabilities of continuing IFX therapy in patients with prolonged immunomodulator use were higher than those in patients on IFX monotherapy. Conclusion: This review of real-world evidence studies confirms the long-term therapeutic benefit of IFX therapy in diverse cohorts of children with luminal CD. Moreover, it supports the view that combination therapy with an immunomodulator prolongs the durability of IFX therapy in patients who previously failed to recover following first-line therapy. The limited number of time-to-event studies in patients on ADA prevented us from drawing definite conclusions about its long-term efficacy.

Clinical Features and Long-Term Outcome in Adult Stroke Patient due to Moyamoya Disease : A Single Subject Study

  • Kwon, Yong Hyun;Kim, Chung Sun
    • The Journal of Korean Physical Therapy
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    • v.25 no.3
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    • pp.126-131
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    • 2013
  • This case report described a single case of adult stoke patient due to Moyamoya disease through long-term follow-up observation, which included his demographics, brain images, and change of motor function and functional activities. The subject was the 54-year-old male diagnosed with left hemiparesis from a stroke due to multifocal encephalomalacia in both hemispheres. At the time of the stroke attack, he took brain surgery intervention including external ventricular drain. Physical and occupational therapy for stroke rehabilitation were admitted including muscle strengthening exercises, functional activity/ADL training, neurofacilitative techniques with bobath or proprioceptive neuromuscular facilitation concepts, and compensatory strategy. Patient's MRI showed that right frontal lobe, right peri-ventricular area, left parietal, and left occipital lobes were damaged, and MRA showed that abnormal collateral vessel was richly developed in both hemispheres by occlusion of proximal internal carotid arteries in both sides. His motor strength was improved from poor to good grade in all of upper and lower limb motions, that MBC was improved from stage 1 to stage 5. In FAC and barthel index, at the initial evaluation, he could not perform any functional movement, but his FAC and barthel index were on 3 and 14 points at present, respectively. During long-term follow-up for approximately 4 years, the subject's functional motor ability was improved, as similar with recovery progression of usual stroke patient. We believe that this single case report will provide clinical information and concern regarding Moyamoya disease with physical therapist, in terms of such as epidemiology, pathogenesis, diagnostic procedures, clinical features, recovery process, and prognosis.

Monitoring and Long-term Trend of Total Column Ozone from Dobson Spectrophotometer in Seoul (1985~2017) (돕슨 분광광도계를 이용한 서울 상공의 오존층 감시 및 장기변화 경향(1985~2017))

  • Park, Sang Seo;Cho, Hi Ku;Koo, Ja-Ho;Lim, Hyunkwang;Lee, Hana;Kim, Jhoon;Lee, Yun Gon
    • Atmosphere
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    • v.29 no.1
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    • pp.13-20
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    • 2019
  • Since 1985, the Dobson Spectrophotometer has been operated at Yonsei University, and this instrument has monitored the daily representative total ozone in Seoul. Climatological value for total ozone in Seoul is updated by using the daily representative observation data from 1985 to 2017. After updating the daily representative total ozone data, seasonal and inter-annual variation of total ozone in Seoul is also estimated after calculating inter-comparison between ground (Dobson Spectrophotometer) and satellite [Total Ozone Mapping Spectrometer (TOMS) and Ozone Monitoring Instrument (OMI)] observations. The global average of total ozone measured by satellite is 297 DU, and its recent amount is about 3.5% lower than the global amount in 1980s. In Seoul, daily representative total ozone is ranged from 225 DU to 518 DU with longterm mean value of 324.3 DU. In addition, monthly mean total ozone is estimated from 290 DU (October) to 362 DU (March), and yearly average of total ozone have been continuously increased since 1985. For the long-term trend of total ozone in Seoul, this study is considered the seasonal variation, Solar Cycle, and Quasi-Biennial Oscillation. In addition to the natural oscillation effect, this study also considered to the long-term variation of sudden increase of total ozone due to the secondary ozone peak. By considering these natural effects, the long-term total ozone trends from 1985 to 2017 are estimated to be 1.11~1.46%/decade.

Possibility analysisof future droughts using long short term memory and standardized groundwater level index (LSTM과 SGI를 이용한 미래 가뭄 발생 가능성 분석)

  • Lim, Jae Deok;Yang, Jeong-Seok
    • Journal of Korea Water Resources Association
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    • v.53 no.2
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    • pp.131-140
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    • 2020
  • The purpose of this study is to analyze the possibility of future droughts by calculating the Standardized Groundwater level Index(SGI) after predicting groundwater level using Long Short Term Memory (LSTM) model. The groundwater level of the Kumho River basin was predicted for the next three years by using the LSTM model, and it was validated through RMSE after learning with observation data except the last three years. The temporal SGI was calculated by using the prediction data and the observation data. The calculated SGI was interpolated within the study area, and the spatial SGI was calculated as the average value for each catchment using the interpolated SGI. The possibility of spatio-temporal drought was analyzed using calculated spatio-temporal SGI. It is confirmed that there is a spatio-temporal difference in the possibility of drought. Through the improvement of deep learning model and diversification of validation method, it is expected to obtain more reliable prediction results and the expansion of study area can be used to respond to drought nationwide, and furthermore it can provide important information for future water resource management.