• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.299-299
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• 2023

토양수분(soil moisture)은 수문인자의 하나로서 토양 내에 함유된 물의 양을 의미하며, 그 총량은 미미하지만 대기와 지표면 사이에서 일어나는 복잡한 물순환과 에너지 교환을 이해하는데 있어 필수적이다. 현재 국내에서는 「수자원의 조사·계획 및 관리에 관한 법률」(이하 수자원법)에 근거해 토양수분량 관측이 이루어지고 있으며, 수자원 분야의 한국수자원조사기술원 외에도 농업, 임업 분야에서도 다양한 기관에서 지상관측소를 구축해 토양수분량을 측정하고 있다. 국내 지상관측소에서는 주로 지점규모(point scale)로 토양수분량을 관측하는 장비가 사용되고 있으며, 유전율식 장비인 TDR(Time Domain Reflectometry), FDR(Frequency Domain Reflectometry)이나 토양수분장력을 측정하는 장력계(Tensiometer)가 널리 쓰이고 있다. 수자원분야에서는 토양 내 수분의 양을 직관적으로 확인할 수 있는 유전율식 장비가 대중적으로 사용되고 있으며, 최근에는 우주선(Cosmic-Ray)으로부터 발생하는 고속중성자(Fast Neutron)를 통해 중규모 면단위(field scale) 토양수분량을 관측하는 장비인 CRNP(Cosmic-Ray Neutron Probe)에 대한 연구도 활발히 진행되고 있다. 이러한 장비는 주로 야외에 설치해 운영하고 있기 때문에 장비 훼손이나 전원공급의 어려움으로 결측이나 오측이 발생할 수 있다. 토양수분량 시계열자료의 결측이나 오측이 일반적인 감쇄기에 발생했다면 선형보간법으로도 간단히 보간할 수 있지만, 강우에 의한 상승기에 발생했다면 해당 강우사상에서의 토양수분량의 상한치를 알기 어려워 결측보간에 어려움이 있다. 본 연구에서는 토양수분량 시계열자료의 강우기간 결측을 보간하는 방법으로 누적분포함수 역변환 샘플링방법을 선택하였다. 연구에는 음성군(차곡리) 토양수분량 관측소 2021년 자료가 사용되었으며, 관측소 56개 지점 중 임의의 지점에 결측구간을 생성한 뒤 해당 지점과의 상관계수가 높은 지점의 누적분포함수를 이용해 역변환 샘플링 방식으로 임의 지점의 결측을 보간하고 그 결과를 기존값과 비교해 보간 방법의 정확도를 평가하였다.

• Korea Journal of Hospital Management
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• v.27 no.4
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• pp.13-21
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• 2022

Purpose: The purpose of this study was to analyze the association between single-person households & Beneficiary of National Basic Livelihood and recommendation on alcohol consumption, and counseling on drinking problems for adults 19 years of age or older. Methods: In this study, excluding missing values, the association between the single-person household & Beneficiary of National Basic Livelihood and recommendation to refrain drinking alcohol, counseling for drinking problems was analyzed by using the chi-squre test and logistic regression analysis. Results: In the case of non-single person households, compared to single-person households, the recommendation rate to refrain drinking alcohol was 1.519 OR (Odds Ratio [OR]: 1.159 , p-value <.0001). meanwhile, in the case of Beneficiary of National Basic Livelihood, the recommendation rate to refrain alcohol consumption was higher by 1.414 OR (OR: 1.414, p-value: 0.011), and the drinking problem counseling rate was also higher by 2.257 OR (OR: 2.257, p-value: 0.026) compared to non-beneficiary group. Discussion & Conclusion: Based on the 2016-2019 National Health and Nutrition Survey, this study investigated the associaiton between single households & Beneficiary of National Basic Livelihood and recommendations to refrain alcohol, and counseling on drinking problems. Compared to the Beneficiary of National Basic Livelihood group, single-person household group has recently been classified as a socially vulnerable group, but it is not applicable in the policy category. If policy and institutional measures for treatment are provided, it is expected that the problem of alcohol abuse can be reduced.

• Journal of Oriental Neuropsychiatry
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• v.34 no.1
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• pp.33-42
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• 2023

Objectives: This study was conducted to observe the progression of symptoms according to the treatment period of patients with social anxiety disorder who received complex Korean medicine treatment. Methods: The medical records of 25 patients who were diagnosed with social anxiety disorder according to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, and received complex Korean medicine treatment (herbal medicine, acupuncture, and Korean psychotherapy) for 12 weeks were analyzed. The State-Trait Anxiety Inventory (STAI), the Beck Depression Inventory-II (BDI-II), the Beck Anxiety Inventory (BAI), the Korean-Social Avoidance and Distress scale (K-SAD), and the Korean-Fear of Negative Evaluation (K-FNE) were measured at the initial hospital visit and during the 4, 8, and 12 weeks of treatment to evaluate the effectiveness of treatment. Missing values were replaced with the average evaluation index value at that time. Results: 1) Statistically significant changes in STAI-X1, STAI-X2, BDI-II, BAI, K-SAD, and K-FNE scores were seen according to the time of treatment. 2) When scores were compared between each treatment time point, STAI-X2 and BDI-II showed statistically significant changes between the initial visit and four weeks of treatment, the initial visit and eight weeks of treatment, and the initial visit and 12 weeks of treatment. STAI-X1 and K-FNE showed statistically significant changes between the initial visit and eight weeks of treatment and the initial visit and 12 weeks of treatment. There was a statistically significant change in BAI scores between the initial visit and the 12th week of treatment. Conclusions: Complex Korean medicine treatment alleviated anxiety, depression, fear, and avoidance of social situation symptoms in patients with social anxiety disorder. The longer the treatment period, the more symptoms tended to be alleviated. However, the evidence should be supplemented with prospective, controlled research.

• KIPS Transactions on Software and Data Engineering
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• v.11 no.3
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• pp.107-114
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• 2022

In this paper, we have enhanced the risk prediction of hypertension using the feature selection method in the Korean National Health and Nutrition Examination Survey (KNHANES) database of the Korea Centers for Disease Control and Prevention. The study identified various risk factors correlated with chronic hypertension. The paper is divided into three parts. Initially, the data preprocessing step of removes missing values, and performed z-transformation. The following is the feature selection (FS) step that used a factor analysis (FA) based on the feature selection method in the dataset, and feature importance (FI) and multicollinearity analysis (MC) were compared based on FS. Finally, in the predictive analysis stage, it was applied to detect and predict the risk of hypertension. In this study, we compare the accuracy, f-score, area under the ROC curve (AUC), and mean standard error (MSE) for each model of classification. As a result of the test, the proposed MC-FA-RF model achieved the highest accuracy of 80.12%, MSE of 0.106, f-score of 83.49%, and AUC of 85.96%, respectively. These results demonstrate that the proposed MC-FA-RF method for hypertension risk predictions is outperformed other methods.

• Journal of Convergence for Information Technology
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• v.12 no.3
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• pp.55-65
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• 2022

Elderly people with Parkinson's disease have higher rates of physical and mental risk factors for falls than non-Parkinson's disease elderly. The purpose of this study is to investigate this by using national data that includes the entire population of the elderly in Korea. As a secondary analysis study using data survey on the elderly by the Ministry of Health and Welfare in 2017, there were a total of 103 elderly people with Parkinson's disease, and a total of 96 subjects were analyzed excluding missing values. In the elderly with Parkinson's disease, the factor most influencing the fall was IADL, and IADL is related to motor control function. Decreased motor control limits physical movements essential for daily life, and even affects self-protective behavior in emergency situations, affecting falls. Based on the research results that IADL can affect falls, various exercise therapies for fall prevention interventions in the elderly with Parkinson's disease can be suggested.

• Journal of Korean Neurosurgical Society
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• v.66 no.4
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• pp.382-392
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• 2023

Objective : The use of indocyanine green videoangiography (ICG-VA) to assess blood flow in the brain during cerebrovascular surgery has been increasing. Clinical studies on ICG-VA have predominantly focused on qualitative analysis. However, quantitative analysis numerical modelling for time profiling enables a more accurate evaluation of blood flow kinetics. In this study, we established a multiple exponential modified Gaussian (multi-EMG) model for quantitative ICG-VA to understand accurately the status of cerebral hemodynamics. Methods : We obtained clinical data of cerebral blood flow acquired the quantitative analysis ICG-VA during cerebrovascular surgery. Varied asymmetric peak functions were compared to find the most matching function form with clinical data by using a nonlinear regression algorithm. To verify the result of the nonlinear regression, the mode function was applied to various types of data. Results : The proposed multi-EMG model is well fitted to the clinical data. Because the primary parameters-growth and decay rates, and peak center and heights-of the model are characteristics of model function, they provide accurate reference values for assessing cerebral hemodynamics in various conditions. In addition, the primary parameters can be estimated on the curves with partially missed data. The accuracy of the model estimation was verified by a repeated curve fitting method using manipulation of missing data. Conclusion : The multi-EMG model can possibly serve as a universal model for cerebral hemodynamics in a comparison with other asymmetric peak functions. According to the results, the model can be helpful for clinical research assessment of cerebrovascular hemodynamics in a clinical setting.

• The Journal of Bigdata
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• v.6 no.2
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• pp.39-49
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• 2021

Recently, large and diverse weather data are being collected by sensors from various sources. Efforts to predict the concentration of fine dust through machine learning are being made everywhere, and this study intends to compare PM10 and PM2.5 prediction models using data from 840 outdoor air meters installed throughout the city. Information can be provided in real time by predicting the concentration of fine dust after 5 minutes, and can be the basis for model development after 10 minutes, 30 minutes, and 1 hour. Data preprocessing was performed, such as noise removal and missing value replacement, and a derived variable that considers temporal and spatial variables was created. The parameters of the model were selected through the response surface method. XGBoost, Random Forest, and Deep Learning (Multilayer Perceptron) are used as predictive models to check the difference between fine dust concentration and predicted values, and to compare the performance between models.

• The Journal of the Acoustical Society of Korea
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• v.42 no.4
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• pp.313-319
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• 2023

In this paper, a time series machine learning model, Long Short Term Memory (LSTM), is applied into the bubble flow noise data and the underwater projectile launch noise data to predict missing values of time-series underwater noise data. The former is mixed with bubble noise, flow noise, and fluid-induced interaction noise measured in a pipe and can be classified into three types. The latter is the noise generated when an underwater projectile is ejected from a launch tube and has a characteristic of instantaenous noise. For such types of noise, a data-driven model can be more useful than an analytical model. We constructed an LSTM model with given data and evaluated the model's performance based on the number of hidden units, the number of input sequences, and the decimation factor of signal. It is shown that the optimal LSTM model works well for new data of the same type.

• The Journal of the Convergence on Culture Technology
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• v.9 no.2
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• pp.151-157
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• 2023

This study investigated the effect of calling on job burnout among nursing care workers, and a total of 230 copies were distributed to analyze 198 copies, excluding 32 copies of questionnaires with poor or missing answers. The correlation between factors on job burnout was found to have a positive correlation coefficient in the values of personal environment meaning and work meaning, and as a result of examining the effect of sub-factors of calling consciousness on job burnout, it was found that personal environment suitability had a significant effect. In order to reduce the job exhaustion of nursing care workers comprehensively, it is necessary to provide an environment for working at an institution. In addition, it will be necessary to activate the relevant institution in preparation for problems occurring in the workplace.

• 한국노년학
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• v.31 no.4
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• pp.925-938
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• 2011

In this study, we investigated the effects of ageism experience of the elderly on depression, where the loneliness was mediated between ageism experience and depression. To investigate the cause and effect of factors, we purposively collected 309 samples from 16 Gyungrodangs evenly located in Jeonju and 291 samples, survived the data screening such as missing values, outliers, normality and covariance conditions, were analyzed by frequency, factor analysis, reliability, confirmatory factor analysis and structural equation model analysis. As the results, first, we confirmed ageism experience positively affected depression of the elderly. Second, ageism experience of the elderly also positively affected loneliness. Third, loneliness positively influenced depression. Fourth, ageism experience had effects directly as well as indirectly on depression medicated by loneliness. Based on the results, in the aged society, combating law, policy, and propaganda against ageism would be helpful to the elderly and individually customized program for ageism victim's mental health would be recommended.