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Evaluation of Space-based Wetland InSAR Observations with ALOS-2 ScanSAR Mode (습지대 변화 관측을 위한 ALOS-2 광대역 모드 적용 연구)

  • Hong, Sang-Hoon;Wdowinski, Shimon
    • Korean Journal of Remote Sensing
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    • v.38 no.5_1
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    • pp.447-460
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    • 2022
  • It is well known that satellite synthetic aperture radar interferometry (InSAR) has been widely used for the observation of surface displacement owing to earthquakes, volcanoes, and subsidence very precisely. In wetlands where vegetation exists on the surface of the water, it is possible to create a water level change map with high spatial resolution over a wide area using the InSAR technique. Currently, a number of imaging radar satellites are in operation, and most of them support a ScanSAR mode observation to gather information over a large area at once. The Cienaga Grande de Santa Marta (CGSM) wetland, located in northern Colombia, is a vast wetland developed along the Caribbean coast. The CGSM wetlands face serious environmental threats from human activities such as reclamation for agricultural uses and residential purposes as well as natural causes such as sea level rise owing to climate change. Various restoration and protection plans have been conducted to conserve these invaluable environments in recognition of the ecological importance of the CGSM wetlands. Monitoring of water level changes in wetland is very important resources to understand the hydrologic characteristics and the in-situ water level gauge stations are usually utilized to measure the water level. Although it can provide very good temporal resolution of water level information, it is limited to fully understand flow pattern owing to its very coarse spatial resolution. In this study, we evaluate the L-band ALOS-2 PALSAR-2 ScanSAR mode to observe the water level change over the wide wetland area using the radar interferometric technique. In order to assess the quality of the interferometric product in the aspect of spatial resolution and coherence, we also utilized ALOS-2 PALSAR-2 stripmap high-resolution mode observations.

A Study on the Educational Necessity and Activation Plan of Image Making Program for Life Care (라이프케어를 위한 이미지메이킹 프로그램 교육의 필요성과 활성화 방안)

  • Yoon, Hee
    • Journal of Korea Entertainment Industry Association
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    • v.14 no.7
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    • pp.429-437
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    • 2020
  • This study is aimed at exploring the current state, necessity and activation of curriculum related to image making program in domestic colleges. To achieve this, an empirical survey was carried out to college students to provide basic data for the development of image making education program in the college curriculum as a measure to guide job interviews with them and improve interpersonal skills of employees-to-be. To achieve this, a survey was carried out to 400 college students in Gwangju and Jeonnam areas. The analysis was conducted to verify the collected data using SPSS v. 21.0 through the process of data coding and data cleaning. The results are as follows. First, the necessity of image making program curriculum showed that they needed the image making program in the college curriculum, the image making program curriculum to get a job and manage an image of employees-to-be after graduation, and other people's help to figure out the images objectively. Second, the educational importance of image making program showed that attitude (behavior) was the highest, followed by manners & greeting, look, speech, relationship, clothes, hairstyle, and makeup. In terms of the important educational factors of image making program, look was the highest, followed by makeup, hairstyle, attitude (behavior), relationship, speech, clothes, and manners & greeting, which look was the most important. Third, the educational influence of image making program showed that the influence on employment was the highest, followed by the influence on relationship, and the influence on life. Fourth, the educational activation of image making program showed that the appropriate educational time for image making program they want was from the second year. Education hours they want were once a week for one semester. And the curriculum they want was liberal arts or an optional course of liberal arts. In terms of image making program-related curriculum contents, manner & greeting was the highest, followed by makeup & coordination, job fair, education to acquire a skill qualification, and training for domestic companies, which their biggest wish was manner & greeting. And image making program leaders they want were major professors. In terms of image making program-related education, speech or voice was the highest, followed by education to analyze communication, education to analyze and practice matching hairstyles and makeup, Education on corporate interviews, and education on walking or posture correction, which their biggest wish was speech or voice and education to analyze communication.

Structural relationship among justice of non-face-to-face exam, trust, and satisfaction with university (치위생(학)과 학생이 지각한 비대면 시험의 공정성, 시험 불안 및 학교 신뢰 간의 구조적 관계)

  • Hyeong-Mi Kim;Chang-Hee Kim;Jeong-Hee Kim
    • Journal of Korean Dental Hygiene Science
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    • v.6 no.1
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    • pp.37-50
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    • 2023
  • Background: This study investigated the structural relationships among justice, test anxiety, and school reliability s non-face-to-face tests of dental hygiene students. Methods: A survey was conducted with 267 dental hygiene students. The survey items included general characteristics, opinions on evaluation, the fairness of non-face-to-face tests (distributive, procedural, and interactional justice), school satisfaction, and school reliability. For statistical analysis, independent-sample t-tests, one-way ANOVA, and structural modeling analyses were performed. Results: Among factors that directly affected distributive justice and reliability towards non-face-to-face tests, the higher the interactional justice (β=0.401, p<0.001) and distributive justice (β=0.232, p=0.002) levels, the higher the school satisfaction. The higher the school satisfaction (β=0.606, p<0.001) and procedural justice (β=0.299, p<0.001) levels, the higher the perceived reliability of the school. Factors that indirectly affected school reliability included interactional justice (β=0.243, p=0.010) and distributive justice (β=0.141, p=0.010). Interactional justice (β=0.592, p=0.010) and distributive justice (β=0.208, p=0.010) were the factors affecting school satisfaction. Moreover, factors that influenced school reliability were distributive justice (β=0.56, p=0.010), interactional justice (β=0.332, p=0.010), procedural justice (β=0.229, p=0.010), and distributive justice (β=0.116, p=0.010). Conclusions: Students will trust and be satisfied with schools when schools and professors sufficiently provide information on face-to-face tests and ensure proper procedures to achieve reasonable grades as rewards for exerted time and effort. Furthermore, this study provides a reference base for developing a variety of content for fair, non-face-to-face tests, thereby allowing students to trust their schools.

K-DEV: A Borehole Deviation Logging Probe Applicable to Steel-cased Holes (철재 케이싱이 설치된 시추공에서도 적용가능한 공곡검층기 K-DEV)

  • Yoonho, Song;Yeonguk, Jo;Seungdo, Kim;Tae Jong, Lee;Myungsun, Kim;In-Hwa, Park;Heuisoon, Lee
    • Geophysics and Geophysical Exploration
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    • v.25 no.4
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    • pp.167-176
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    • 2022
  • We designed a borehole deviation survey tool applicable for steel-cased holes, K-DEV, and developed a prototype for a depth of 500 m aiming to development of own equipment required to secure deep subsurface characterization technologies. K-DEV is equipped with sensors that provide digital output with verified high performance; moreover, it is also compatible with logging winch systems used in Korea. The K-DEV prototype has a nonmagnetic stainless steel housing with an outer diameter of 48.3 mm, which has been tested in the laboratory for water resistance up to 20 MPa and for durability by running into a 1-km deep borehole. We confirmed the operational stability and data repeatability of the prototype by constantly logging up and down to the depth of 600 m. A high-precision micro-electro-mechanical system (MEMS) gyroscope was used for the K-DEV prototype as the gyro sensor, which is crucial for azimuth determination in cased holes. Additionally, we devised an accurate trajectory survey algorithm by employing Unscented Kalman filtering and data fusion for optimization. The borehole test with K-DEV and a commercial logging tool produced sufficiently similar results. Furthermore, the issue of error accumulation due to drift over time of the MEMS gyro was successfully overcome by compensating with stationary measurements for the same attitude at the wellhead before and after logging, as demonstrated by the nearly identical result to the open hole. We believe that the methodology of K-DEV development and operational stability, as well as the data reliability of the prototype, were confirmed through these test applications.

Dietary habits and nutrient intake status of university students according to obesity risk based on body mass index and percent body fat (BMI와 체지방률을 고려한 비만위험도 판정에 따른 대학생의 식생활 및 섭취 양상 연구)

  • Chae Hong Lee;Kyung A Lee
    • Journal of Nutrition and Health
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    • v.56 no.6
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    • pp.714-729
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    • 2023
  • Purpose: Since the coronavirus pandemic, the number of obese people has increased, and accelerated aging has been reported, particularly among young population. Therefore, this study analyzed the dietary habits of university students according to their risk of obesity to provide data for improving their eating habits. Methods: Ninety students at Daegu Catholic University were surveyed for their eating habits and photo-enhanced meal intake. The obesity risk was categorized as normal if the body mass index (BMI) and percent body fat (PBF) were normal, at-risk if both indicated overweight or obese, obesity in BMI alone were analyzed as BMI group and those with obesity in percent body fat alone were analyzed as PBF group. Results: There were 23 (25.5%) in the normal group, 10 (11.1%) in the BMI group, 24 (26.7%) in the PBF group and 33 (36.7%) in the at-risk group. The dietary survey showed that the risk groups had lower consumption frequencies of vegetables (p < 0.05) than the normal group, had less sleep time (p < 0.05) and higher frequency of fast food consumption (p < 0.001). The intake of vegetables was significantly higher in the normal group than in the risk group (p < 0.05). In terms of the daily nutrient intake, there was no significant difference in energy intake according to the obesity risk, but the intakes of dietary fiber (p < 0.01), vitamin A (p < 0.01), vitamin C (p < 0.01) were higher in the normal group than in the risk groups. Conclusion: Therefore, it is important to consider the BMI and percent body fat together to diagnose obesity and provide nutrition education and counseling.

Analysis of Micro-Sedimentary Structure Characteristics Using Ultra-High Resolution UAV Imagery: Hwangdo Tidal Flat, South Korea (초고해상도 무인항공기 영상을 이용한 한국 황도 갯벌의 미세 퇴적 구조 특성 분석)

  • Minju Kim;Won-Kyung Baek;Hoi Soo Jung;Joo-Hyung Ryu
    • Korean Journal of Remote Sensing
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    • v.40 no.3
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    • pp.295-305
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    • 2024
  • This study aims to analyze the micro-sedimentary structures of the Hwangdo tidal flats using ultra-high resolution unmanned aerial vehicle (UAV) data. Tidal flats, located in the transitional area between land and sea, constantly change due to tidal activities and provide a unique environment important for understanding sedimentary processes and environmental conditions. Traditional field observation methods are limited in spatial and temporal coverage, and existing satellite imagery does not provide sufficient resolution to study micro-sedimentary structures. To overcome these limitations, high-resolution images of the Hwangdo tidal flats in Chungcheongnam-do were acquired using UAVs. This area has experienced significant changes in its sedimentary environment due to coastal development projects such as sea wall construction. From May 17 to 18, 2022, sediment samples were collected from 91 points during field surveys and 25 in-situ points were intensively analyzed. UAV data with a spatial resolution of approximately 0.9 mm allowed identifying and extracting parameters related to micro-sedimentary structures. For mud cracks, the length of the major axis of the polygons was extracted, and the wavelength and ripple symmetry index were extracted for ripple marks. The results of the study showed that in areas with mud content above 80%, mud cracks formed at an average major axis length of 37.3 cm. In regions with sand content above 60%, ripples with an average wavelength of 8 cm and a ripple symmetry index of 2.0 were formed. This study demonstrated that micro-sedimentary structures of tidal flats can be effectively analyzed using ultra-high resolution UAV data without field surveys. This highlights the potential of UAV technology as an important tool in environmental monitoring and coastal management and shows its usefulness in the study of sedimentary structures. In addition, the results of this study are expected to serve as baseline data for more accurate sedimentary facies classification.

A Study on the Medical Application and Personal Information Protection of Generative AI (생성형 AI의 의료적 활용과 개인정보보호)

  • Lee, Sookyoung
    • The Korean Society of Law and Medicine
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    • v.24 no.4
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    • pp.67-101
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    • 2023
  • The utilization of generative AI in the medical field is also being rapidly researched. Access to vast data sets reduces the time and energy spent in selecting information. However, as the effort put into content creation decreases, there is a greater likelihood of associated issues arising. For example, with generative AI, users must discern the accuracy of results themselves, as these AIs learn from data within a set period and generate outcomes. While the answers may appear plausible, their sources are often unclear, making it challenging to determine their veracity. Additionally, the possibility of presenting results from a biased or distorted perspective cannot be discounted at present on ethical grounds. Despite these concerns, the field of generative AI is continually advancing, with an increasing number of users leveraging it in various sectors, including biomedical and life sciences. This raises important legal considerations regarding who bears responsibility and to what extent for any damages caused by these high-performance AI algorithms. A general overview of issues with generative AI includes those discussed above, but another perspective arises from its fundamental nature as a large-scale language model ('LLM') AI. There is a civil law concern regarding "the memorization of training data within artificial neural networks and its subsequent reproduction". Medical data, by nature, often reflects personal characteristics of patients, potentially leading to issues such as the regeneration of personal information. The extensive application of generative AI in scenarios beyond traditional AI brings forth the possibility of legal challenges that cannot be ignored. Upon examining the technical characteristics of generative AI and focusing on legal issues, especially concerning the protection of personal information, it's evident that current laws regarding personal information protection, particularly in the context of health and medical data utilization, are inadequate. These laws provide processes for anonymizing and de-identification, specific personal information but fall short when generative AI is applied as software in medical devices. To address the functionalities of generative AI in clinical software, a reevaluation and adjustment of existing laws for the protection of personal information are imperative.

Current and Future Operation of Menu Management in the School Foodservices of Chungbuk (1) - Menu Planning - (충북지역 학교급식 영양(교)사의 식단관리 운영실태 및 개선방안(1) - 식단계획 -)

  • Ahn, Yoon-Ju;Lee, Young-Eun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.41 no.8
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    • pp.1118-1133
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    • 2012
  • This research aimed to suggest an efficient improvement plan for school food services by investigating the operating situation and recognition of menu management in school food services for school food service dietitians (and nutrition teachers) in Chungbuk. A total of 328 questionnaires were distributed to school food service dietitians (and nutrition teachers) in Chungbuk by e-mail in September, 2010. A total of 265 questionnaires (80.8%) were used for the analysis. The highest allocation of nutrients and calories per day in school food services was 1:1.5:1.5 (breakfast : lunch : dinner) (38.5%). The reasoning for applying a flexible allocation of nutrients and calories per day was 'considering the ratio of students who do not eat breakfast' (59.2%). And the way to apply the flexible allocation for nutrients and calories per day was 'by agreement from the school operating committee in arbitrary data without situation surveys' (86 respondents, 49.4%), and 'by agreement from the school operating committee in analysis data through situation surveys' (80 respondents, 46.0%). The operational method of standardized recipes was 'cooking management site of national education information systems' (87.5%) and the items included in standardized recipes were menu name, food material name, portion size, cooking method, nutrition analysis, and critical control point in HACCP. The main reason for not utilizing all items of a cooking management site of the national education information system was 'no big trouble in menu management even though it is used partly (29.1%). In addition, the highest use of standardized recipe was for 'maintaining consistency of food production quantity' (74.0%).

Estimation of GARCH Models and Performance Analysis of Volatility Trading System using Support Vector Regression (Support Vector Regression을 이용한 GARCH 모형의 추정과 투자전략의 성과분석)

  • Kim, Sun Woong;Choi, Heung Sik
    • Journal of Intelligence and Information Systems
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    • v.23 no.2
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    • pp.107-122
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    • 2017
  • Volatility in the stock market returns is a measure of investment risk. It plays a central role in portfolio optimization, asset pricing and risk management as well as most theoretical financial models. Engle(1982) presented a pioneering paper on the stock market volatility that explains the time-variant characteristics embedded in the stock market return volatility. His model, Autoregressive Conditional Heteroscedasticity (ARCH), was generalized by Bollerslev(1986) as GARCH models. Empirical studies have shown that GARCH models describes well the fat-tailed return distributions and volatility clustering phenomenon appearing in stock prices. The parameters of the GARCH models are generally estimated by the maximum likelihood estimation (MLE) based on the standard normal density. But, since 1987 Black Monday, the stock market prices have become very complex and shown a lot of noisy terms. Recent studies start to apply artificial intelligent approach in estimating the GARCH parameters as a substitute for the MLE. The paper presents SVR-based GARCH process and compares with MLE-based GARCH process to estimate the parameters of GARCH models which are known to well forecast stock market volatility. Kernel functions used in SVR estimation process are linear, polynomial and radial. We analyzed the suggested models with KOSPI 200 Index. This index is constituted by 200 blue chip stocks listed in the Korea Exchange. We sampled KOSPI 200 daily closing values from 2010 to 2015. Sample observations are 1487 days. We used 1187 days to train the suggested GARCH models and the remaining 300 days were used as testing data. First, symmetric and asymmetric GARCH models are estimated by MLE. We forecasted KOSPI 200 Index return volatility and the statistical metric MSE shows better results for the asymmetric GARCH models such as E-GARCH or GJR-GARCH. This is consistent with the documented non-normal return distribution characteristics with fat-tail and leptokurtosis. Compared with MLE estimation process, SVR-based GARCH models outperform the MLE methodology in KOSPI 200 Index return volatility forecasting. Polynomial kernel function shows exceptionally lower forecasting accuracy. We suggested Intelligent Volatility Trading System (IVTS) that utilizes the forecasted volatility results. IVTS entry rules are as follows. If forecasted tomorrow volatility will increase then buy volatility today. If forecasted tomorrow volatility will decrease then sell volatility today. If forecasted volatility direction does not change we hold the existing buy or sell positions. IVTS is assumed to buy and sell historical volatility values. This is somewhat unreal because we cannot trade historical volatility values themselves. But our simulation results are meaningful since the Korea Exchange introduced volatility futures contract that traders can trade since November 2014. The trading systems with SVR-based GARCH models show higher returns than MLE-based GARCH in the testing period. And trading profitable percentages of MLE-based GARCH IVTS models range from 47.5% to 50.0%, trading profitable percentages of SVR-based GARCH IVTS models range from 51.8% to 59.7%. MLE-based symmetric S-GARCH shows +150.2% return and SVR-based symmetric S-GARCH shows +526.4% return. MLE-based asymmetric E-GARCH shows -72% return and SVR-based asymmetric E-GARCH shows +245.6% return. MLE-based asymmetric GJR-GARCH shows -98.7% return and SVR-based asymmetric GJR-GARCH shows +126.3% return. Linear kernel function shows higher trading returns than radial kernel function. Best performance of SVR-based IVTS is +526.4% and that of MLE-based IVTS is +150.2%. SVR-based GARCH IVTS shows higher trading frequency. This study has some limitations. Our models are solely based on SVR. Other artificial intelligence models are needed to search for better performance. We do not consider costs incurred in the trading process including brokerage commissions and slippage costs. IVTS trading performance is unreal since we use historical volatility values as trading objects. The exact forecasting of stock market volatility is essential in the real trading as well as asset pricing models. Further studies on other machine learning-based GARCH models can give better information for the stock market investors.

Analysis of the Perception of Hospice and Narcotic Analgesics by Family Caregivers of Terminal Cancer Patient (말기 암 환자 보호자의 호스피스와 마약성 진통제에 대한 인식도 분석)

  • Kwak, Kyung-Sook;Chun, Sung-Ho;Ha, Jung-Ok;Lee, Kyung-Hee
    • Journal of Hospice and Palliative Care
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    • v.9 no.2
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    • pp.106-111
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    • 2006
  • Purpose: In terminal cancer patients, pain control with narcotic analgesics and supportive care by hospice are very useful treatment modality. However, many patients and their caregivers are poorly compliant in using narcotic analgesics for fear of addiction and tolerance. And also many patients and family caregivers are reluctant to accept hospice, presuming that hospice means patient's condition is no longer reversible and progressively deteriorating. The purpose of this study was to evaluate and analyze the perception of using narcotic analgesics and hospice by family caregivers of terminal cancer patients who play a critical role in health care in Korean culture. Methods: A total of 54 terminal ranter patient's family caregivers participated in this study. Questionnaire consisted of 15 questions about narcotic analgesics and hospice. Results: The study revealed following results. 1) family caregivers who are not aware of hospice are more than half (56.7%). 2) 81.8% of family caregivers agreed that hospice care is beneficial to terminal cancer patients. 3) 85.1% of family caregivers were under financial burden. 4) 83.2% of patient complained pain in 24 hours. 3) while 88.5% of family caregivers believed that narcotic analgesics can control pair, 79.1% and 79.6% of them also believed that use of narcotic analgesics would result in addiction and tolerance, respectively. Conclusion: There still exist barriers to family caregivers in using narcotic analgesics for pain control. And also, terminal cancer patient's family caregivers have poor information about hospice. Therefore, educational intervention about narcotic analgesics by pharmacist and doctors are needed for proper pain control for terminal ranter patients. In addition, more precise information about hospice care should be provided for terminal cancer patients and their family caregivers.

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