• Korean Journal of Remote Sensing
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• v.33 no.5_1
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• pp.455-467
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• 2017

When performing target detection using hyperspectral imagery, a feature extraction process is necessary to solve the problem of redundancy of adjacent spectral bands and the problem of a large amount of calculation due to high dimensional data. This study proposes a new band selection method using the $L_{2,1}$-norm regression model to apply the feature selection technique in the machine learning field to the hyperspectral band selection. In order to analyze the performance of the proposed band selection technique, we collected the hyperspectral imagery and these were used to analyze the performance of target detection with band selection. The Adaptive Cosine Estimator (ACE) detection performance is maintained or improved when the number of bands is reduced from 164 to about 30 to 40 bands in the 350 nm to 2500 nm wavelength band. Experimental results show that the proposed band selection technique extracts bands that are effective for detection in hyperspectral images and can reduce the size of the data without reducing the performance, which can help improve the processing speed of real-time target detection system in the future.

• Journal of the Institute of Electronics and Information Engineers
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• v.53 no.2
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• pp.76-86
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• 2016

SQL Injection attacks are the most widely used and also they are considered one of the oldest traditional hacking techniques. SQL Injection attacks are getting quite complicated and they perform a high portion among web hacking. The big data environments in the future will be widely used resulting in many devices and sensors will be connected to the internet and the amount of data that flows among devices will be highly increased. The scale of damage caused by SQL Injection attacks would be even greater in the future. Besides, creating security solutions against SQL Injection attacks are high costs and time-consuming. In order to prevent SQL Injection attacks, we have to operate quickly and accurately according to this data analysis techniques. We utilized data analytics and machine learning techniques to defend against SQL Injection attacks and analyzed the execution plan of the SQL command input if there are abnormal patterns through checking the web log files. Herein, we propose a way to distinguish between normal and abnormal SQL commands. We have analyzed the value entered by the user in real time using the automated SQL Injection attacks tools. We have proved that it is possible to ensure an effective defense through analyzing the execution plan of the SQL command.

• Korean Journal of Remote Sensing
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• v.37 no.5_2
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• pp.1307-1315
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• 2021

The Changjiang Diluted Water (CDW) spreads over the East China Sea every summer and significantly affects the sea surface salinity changes in the seas around Jeju Island and the southern coast of Korea peninsula. Sometimes its effect extends to the eastern coast of Korea peninsula through the Korea Strait. Specifically, the CDW has a significant impact on marine physics and ecology and causes damage to fisheries and aquaculture. However, due to the limited field surveys, continuous observation of the CDW in the East China Sea is practically difficult. Many studies have been conducted using satellite measurements to monitor CDW distribution in near-real time. In this study, an algorithm for estimating Sea Surface Salinity (SSS) in the East China Sea was developed using the Geostationary Ocean Color Imager (GOCI). The Multilayer Perceptron Neural Network (MPNN) method was employed for developing an algorithm, and Soil Moisture Active Passive (SMAP) SSS data was selected for the output. In the previous study, an algorithm for estimating SSS using GOCI was trained by 2016 observation data. By comparison, the train data period was extended from 2015 to 2020 to improve the algorithm performance. The validation results with the National Institute of Fisheries Science (NIFS) serial oceanographic observation data from 2011 to 2019 show 0.61 of coefficient of determination (R²) and 1.08 psu of Root Mean Square Errors (RMSE). This study was carried out to develop an algorithm for monitoring the surface salinity of the East China Sea using GOCI and is expected to contribute to the development of the algorithm for estimating SSS by using GOCI-II.

• Korean Chemical Engineering Research
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• v.59 no.2
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• pp.209-218
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• 2021

First principle-based modeling studies have been performed to improve the heat exchange efficiency of ORV and optimize operation, but the heat transfer coefficient of ORV is an irregular system according to time and location, and it undergoes a complex modeling process. In this study, FNN, LSTM, and AutoML-based modeling were performed to confirm the effectiveness of data-based modeling for complex systems. The prediction accuracy indicated high performance in the order of LSTM > AutoML > FNN in MSE. The performance of AutoML, an automatic design method for machine learning models, was superior to developed FNN, and the total time required for model development was 1/15 compared to LSTM, showing the possibility of using AutoML. The prediction of NG and seawater discharged temperatures using LSTM and AutoML showed an error of less than 0.5K. Using the predictive model, real-time optimization of the amount of LNG vaporized that can be processed using ORV in winter is performed, confirming that up to 23.5% of LNG can be additionally processed, and an ORV optimal operation guideline based on the developed dynamic prediction model was presented.

• Journal of Korea Water Resources Association
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• v.56 no.4
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• pp.245-259
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• 2023

The agricultural reservoir is a critical water supply system in South Korea, providing approximately 60% of the agricultural water demand. However, the reservoir faces several issues that jeopardize its efficient operation and management. To address this issues, we propose a novel deep-learning-based water level recognition model that uses CCTV image data to accurately estimate water levels in agricultural reservoirs. The model consists of three main parts: (1) dataset construction, (2) image segmentation using the U-Net algorithm, and (3) CCTV-based water level recognition using either CNN or ResNet. The model has been applied to two reservoirs G-reservoir and M-reservoir with observed CCTV image and water level time series data. The results show that the performance of the image segmentation model is superior, while the performance of the water level recognition model varies from 50 to 80% depending on water level classification criteria (i.e., classification guideline) and complexity of image data (i.e., variability of the image pixels). The performance of the model can be improved if more numbers of data can be collected.

• Convergence Security Journal
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• v.23 no.2
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• pp.27-36
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• 2023

In recent years, ransomware attacks have become more organized and specialized, with the sophistication of attacks targeting specific individuals or organizations using tactics such as social engineering, spear phishing, and even machine learning, some operating as business models. In order to effectively respond to this, various researches and solutions are being developed and operated to detect and prevent attacks before they cause serious damage. In particular, honeypots can be used to minimize the risk of attack on IT systems and networks, as well as act as an early warning and advanced security monitoring tool, but in cases where ransomware does not have priority access to the decoy file, or bypasses it completely. has a disadvantage that effective ransomware response is limited. In this paper, this honeypot is optimized for the user environment to create a reliable real-time dynamic honeypot file, minimizing the possibility of an attacker bypassing the honeypot, and increasing the detection rate by preventing the attacker from recognizing that it is a honeypot file. To this end, four models, including a basic data collection model for dynamic honeypot generation, were designed (basic data collection model / user-defined model / sample statistical model / experience accumulation model), and their validity was verified.

• Korean Journal of Remote Sensing
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• v.37 no.6_1
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• pp.1739-1756
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• 2021

Atmospheric nitrogen dioxide (NO₂) is mainly caused by anthropogenic emissions. It contributes to the formation of secondary pollutants and ozone through chemical reactions, and adversely affects human health. Although ground stations to monitor NO₂ concentrations in real time are operated in Korea, they have a limitation that it is difficult to analyze the spatial distribution of NO₂ concentrations, especially over the areas with no stations. Therefore, this study conducted a comparative experiment of spatial interpolation of NO₂ concentrations based on two linear-regression methods(i.e., multi linear regression (MLR), and regression kriging (RK)), and two machine learning approaches (i.e., random forest (RF), and support vector regression (SVR)) for the year of 2020. Four approaches were compared using leave-one-out-cross validation (LOOCV). The daily LOOCV results showed that MLR, RK, and SVR produced the average daily index of agreement (IOA) of 0.57, which was higher than that of RF (0.50). The average daily normalized root mean square error of RK was 0.9483%, which was slightly lower than those of the other models. MLR, RK and SVR showed similar seasonal distribution patterns, and the dynamic range of the resultant NO₂ concentrations from these three models was similar while that from RF was relatively small. The multivariate linear regression approaches are expected to be a promising method for spatial interpolation of ground-level NO₂ concentrations and other parameters in urban areas.

• Economic and Environmental Geology
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• v.54 no.3
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• pp.353-364
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• 2021

Since the mid-twentieth century, geology has gradually evolved as an interdisciplinary context in South Korea. The journal of Economic and Environmental Geology (EEG) has a long history of over 52 years and published interdisciplinary articles based on geology. In this study, we performed a literature review using topic modeling based on Latent Dirichlet Allocation (LDA), an unsupervised machine learning model, to identify geological topics, historical trends (classic topics and emerging topics), and association by analyzing titles, keywords, and abstracts of 2,571 publications in EEG during 1968-2020. The results showed that 8 topics ('petrology and geochemistry', 'hydrology and hydrogeology', 'economic geology', 'volcanology', 'soil contaminant and remediation', 'general and structural geology', 'geophysics and geophysical exploration', and 'clay mineral') were identified in the EEG. Before 1994, classic topics ('economic geology', 'volcanology', and 'general and structure geology') were dominant research trends. After 1994, emerging topics ('hydrology and hydrogeology', 'soil contaminant and remediation', 'clay mineral') have arisen, and its portion has gradually increased. The result of association analysis showed that EEG tends to be more comprehensive based on 'economic geology'. Our results provide understanding of how geological research topics branch out and merge with other fields using a useful literature review tool for geological research in South Korea.

• Korean Journal of Remote Sensing
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• v.39 no.5_3
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• pp.979-995
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• 2023

As wildfires are difficult to predict, real-time monitoring is crucial for a timely response. Geostationary satellite images are very useful for active fire detection because they can monitor a vast area with high temporal resolution (e.g., 2 min). Existing satellite-based active fire detection algorithms detect thermal outliers using threshold values based on the statistical analysis of brightness temperature. However, the difficulty in establishing suitable thresholds for such threshold-based methods hinders their ability to detect fires with low intensity and achieve generalized performance. In light of these challenges, machine learning has emerged as a potential-solution. Until now, relatively simple techniques such as random forest, Vanilla convolutional neural network (CNN), and U-net have been applied for active fire detection. Therefore, this study proposed an active fire detection algorithm using state-of-the-art (SOTA) deep learning techniques using data from the Advanced Himawari Imager and evaluated it over East Asia and Australia. The SOTA model was developed by applying EfficientNet and lion optimizer, and the results were compared with the model using the Vanilla CNN structure. EfficientNet outperformed CNN with F1-scores of 0.88 and 0.83 in East Asia and Australia, respectively. The performance was better after using weighted loss, equal sampling, and image augmentation techniques to fix data imbalance issues compared to before the techniques were used, resulting in F1-scores of 0.92 in East Asia and 0.84 in Australia. It is anticipated that timely responses facilitated by the SOTA deep learning-based approach for active fire detection will effectively mitigate the damage caused by wildfires.

• The Korean Nurse
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• v.20 no.4 s.112
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• pp.39-49
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• 1981

기존 간호 영역 내 간호는 질적으로, 양적으로 급격히 팽창 확대되어 가고 있다. 많은 나라에서 건강관리체계가 부적절하게 분배되어 있으며 따라서 많은 사람들이 적절한 건강관리를 제공받지 못하고 있어 수준 높은 양질의 건강관리를 전체적으로 확대시키는 것이 시급하다. 혹 건강관리의 혜택을 받는다고 해도 이들 역시 보다 더 양질의 인간적인 간호를 요하고 있는 실정이다. 간호는 또한 간호영역 자체 내에서도 급격히 확대되어가고 있다. 예를들면, 미국같은 선진국가의 건강간호사(Nurse practitioner)는 간호전문직의 새로운 직종으로 건강관리체계에서 독자적인 실무자로 그 두각을 나타내고 있다. 의사의 심한 부족난으로 고심하는 발전도상에 있는 나라들에서는 간호원들에게 전통적인 간호기능 뿐 아니라 건강관리체계에서 보다 많은 역할을 수행하도록 기대하며 일선지방의 건강센터(Health center) 직종에 많은 간호원을 투입하고 있다. 가령 우리 한국정부에서 최근에 시도한 무의촌지역에서 졸업간호원들이 건강관리를 제공할 수 있도록 한 법적 조치는 이러한 구체적인 예라고 할 수 있다. 기존 간호영역내외의 이런 급격한 변화는 Melvin Toffler가 말한 대로 ''미래의 충격''을 초래하게 되었다. 따라서 이러한 역동적인 변화는 간호전문직에 대하여 몇가지 질문을 던져준다. 첫째, 미래사회에서 간호영역의 특성은 무엇인가? 둘째, 이러한 새로운 영역에서 요구되는 간호원을 길러내기 위해 간호교육자는 어떤 역할을 수행해야 하는가? 셋째 내일의 간호원을 양성하는 간호교육자를 준비시키기 위한 실질적이면서도 현실적인 전략은 무엇인가 등이다. 1. 미래사회에서 간호영역의 특성은 무엇인가? 미래의 간호원은 다음에 열거하는 여러가지 요인으로 인하여 지금까지의 것과는 판이한 환경에서 일하게 될 것이다. 1) 건강관리를 제공하는 과정에서 컴퓨터화되고 자동화된 기계 및 기구 등 새로운 기술을 많이 사용할 것이다. 2) 1차건강관리가 대부분 간호원에 의해 제공될 것이다. 3) 내일의 건강관리는 소비자 주축의 것이 될 것이다. 4) 간호영역내에 많은 새로운 전문분야들이 생길 것이다. 5) 미래의 건강관리체계는 사회적인 변화와 이의 요구에 더 민감한 반응을 하게 될 것이다. 6) 건강관리체계의 강조점이 의료진료에서 건강관리로 바뀔 것이다. 7) 건강관리체계에서의 간호원의 역할은 의료적인 진단과 치료계획의 기능에서 크게 탈피하여 병원내외에서 보다 더 독특한 실무형태로 발전될 것이다. 이러한 변화와 더불어 미래 간호영역에서 보다 효과적인 간호를 수행하기 위해 미래 간호원들은 지금까지의 간호원보다 더 광범위하고 깊은 교육과 훈련을 받아야 한다. 보다 발전된 기술환경에서 전인적인 접근을 하기위해 신체과학이나 의학뿐 아니라 행동과학 $\cdot$ 경영과학 등에 이르기까지 다양한 훈련을 받아야 할 필요가 있다. 또한 행동양상면에서 전문직인 답게 보다 진취적이고 표현적이며 자동적이고 응용과학적인 역할을 수행하도록 훈련을 받아야 한다. 그리하여 간호원은 효과적인 의사결정자$\cdot$문제해결자$\cdot$능숙한 실무자일 뿐 아니라 소비자의 건강요구를 예리하게 관찰하고 이 요구에 효과적인 존재를 발전시켜 나가는 연구자가 되어야 한다. 2. 미래의 간호교육자는 어떤 역할을 수행해야 하는가? 간호교육은 전문직으로서의 실무를 제공하기 위한 기초석이다. 이는 간호교육자야말로 미래사회에서 국민의 건강요구를 충족시키기는 능력있는 간호원을 공급하는 일에 전무해야 함을 시사해준다. 그러면 이러한 일을 달성하기 위해 간호교육자는 무엇을 해야 하는가? 우선 간호교육자는 두가지 측면에서 이 일을 수정해야 된다고 본다. 그 하나는 간호교육기관에서의 측면이고 다른 하나는 간호교육자 개인적인 측면엣서이다. 우선 간호교육기관에서 간호교육자는 1) 미래사회에서 요구되는 간호원을 교육시키기 위한 프로그램을 제공해야 한다. 2) 효과적인 교과과정의 발전과 수정보완을 계속적으로 진행시켜야 한다. 3) 잘된 교과과정에 따라 적절한 훈련을 철저히 시켜야 한다. 4) 간호교육자 자신이 미래의 예측된 현상을 오늘의 교육과정에 포함시킬 수 있는 자신감과 창의력을 가지고 모델이 되어야 한다. 5) 연구 및 학생들의 학습에 영향을 미치는 중요한 의사결정에 학생들을 참여시키도록 해야한다. 간호교육자 개인적인 측면에서는 교육자 자신들이 능력있고 신빙성있으며 간호의 이론$\cdot$실무$\cdot$연구면에 걸친 권위와 자동성$\cdot$독창성, 그리고 인간을 진정으로 이해하려는 자질을 갖추도록 계속 노력해야 한다. 3. 미래의 간호원을 양성하는 능력있는 간호교육자를 준비시키기 위한 실질적이면서도 현실적인 전략은 무엇인가? 내일의 도전을 충족시킬 수 있는 능력있는 간호교육자를 준비시키기 위한 실질적이고 현실적인 전략을 논함에 있어 우리나라의 실정을 참조하겠다. 전문직 간호교육자를 준비하는데 세가지 방법을 통해 할 수 있다고 생각한다. 첫째는 간호원 훈련수준을 전문직 실무를 수행할 수 있는 단계로 면허를 높이는 것이고, 둘째는 훈련수준을 더 향상시키기 위하여 학사 및 석사간호교육과정을 발전시키고 확대하는 것이며, 셋째는 현존하는 간호교육 프로그램의 질을 높이는 것이다. 첫째와 둘째방법은 정부의 관할이 직접 개입되는 방법이기 때문에 여기서는 생략하고 현존하는 교과과정을 발전시키고 그 질을 향상시키는 것에 대해서만 언급하고자 한다. 미래의 여러가지 도전에 부응할 수 있는 교육자를 준비시키는 교육과정의 발전을 두가지 면에서 추진시킬 수 있다고 본다. 첫째는 국제간의 교류를 통하여 idea 및 경험을 나눔으로서 교육과정의 질을 높일 수 있다. 서로 다른 나라의 간호교육자들이 정기적으로 모여 생각과 경험을 교환하고 연구하므로서 보다 체계적이고 효과적인 발전체인(chain)이 형성되는 것이다. ICN같은 국제적인 조직에 의해 이러한 모임을 시도하는 것인 가치있는 기회라고 생각한다. 국가간 또는 국제적인 간호교육자 훈련을 위한 교육과정의 교환은 한 나라안에서 그 idea를 확산시키는데 효과적인 영향을 미칠 수 있다. 충분한 간호교육전문가를 갖춘 간호교육기관이 새로운 교육과정을 개발하여 그렇지 못한 기관과의 연차적인 conference를 가지므로 확산시킬 수도 있으며 이런 방법은 경제적인 면에서도 효과적일 뿐만 아니라 그 나라 그 문화상황에 적합한 교과과정 개발에도 효과적일 수 있다. 간호교육자를 준비시키는 둘째전략은 현존간호교육자들이 간호이론과 실무$\cdot$연구를 통합하고 발전시키는데 있어서 당면하는 여러가지 요인-전인적인 간호에 적절한 과목을 이수하지 못하고 임상실무경험의 부족등-을 보충하는 방법이다. 이런 실제적인 문제를 잠정적으로 해결하기 위하여 1) 몇몇 대학에서 방학중에 계속교육 프로그램을 개발하여 현직 간호교육자들에게 필요하고 적절한 과목을 이수하도록 한다. 따라서 임상실무교육도 이때 실시할 수 있다. 2) 대학원과정 간호교육프로그램의 입학자의 자격에 2$\~$3년의 실무경험을 포함시키도록 한다. 결론적으로 교수와 학생간의 진정한 동반자관계는 자격을 구비한 능력있는 교수의 실천적인 모델을 통하여서 가능하게 이루어 질수 있다고 믿는 바이다.