• The Journal of the Convergence on Culture Technology
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• v.9 no.1
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• pp.703-709
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• 2023

It is most desirable to train with a real crane in an environment similar to that of a port for crane operation training in charge of loading and unloading in a port, but it has time and space limitations and cost problems. In order to overcome these limitations, VR(Virtual Reality) based crane training programs and related devices are receiving a lot of attention. In this paper, we designed and implemented a VR-based harbor crane simulator operating on an HMD. The simulator developed in this paper consists of a crane simulator program that operates on the HMD, an IoT driving terminal that processes trainees' crane operation input, and a training server that stores trainees' training information. The simulator program provides VR-based crane training scenarios implemented with Unity3D, and the IoT driving terminal developed based on Arduino is composed of two controllers and transmits the user's driving operation to the HMD. In particular, the crane simulator in this paper uses a training server to create a database of environment setting values for each educator, progress and training time, and information on driving warning situations. Through the use of such a server, trainees can use the simulator in a more convenient environment and can expect improved educational effects by providing training information.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.33 no.2
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• pp.193-200
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• 2023

Cryptanalysis can be performed by various techniques such as known plaintext attack, differential attack, side-channel analysis, and the like. Recently, many studies have been conducted on cryptanalysis using deep learning. A known-plaintext attack is a technique that uses a known plaintext and ciphertext pair to find a key. In this paper, we use deep learning technology to perform a known-plaintext attack against S-PRESENT, a reduced version of the lightweight block cipher PRESENT. This paper is significant in that it is the first known-plaintext attack based on deep learning performed on a reduced lightweight block cipher. For cryptanalysis, MLP (Multi-Layer Perceptron) and 1D and 2D CNN(Convolutional Neural Network) models are used and optimized, and the performance of the three models is compared. It showed the highest performance in 2D convolutional neural networks, but it was possible to attack only up to some key spaces. From this, it can be seen that the known-plaintext attack through the MLP model and the convolutional neural network is limited in attackable key bits.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.444-444
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• 2021

하천의 오염부하량 관리 계획은 지속적인 모니터링을 통한 자료 구축과 모형을 이용한 예측결과를 기반으로 수립된다. 하천의 모니터링과 예측 분석은 많은 예산과 인력 등이 필요하나, 정부의 담당 공무원 수는 극히 부족한 상황이 일반적이다. 이에 정부는 전문가에게 관련 용역을 의뢰하지만, 한국과 같이 지형이 복잡한 지역에서의 오염부하량 배출 특성은 각각 다르게 나타나기 때문에 많은 예산 소모가 발생 된다. 이를 개선하고자, 본 연구는 합성곱 신경망 (convolution neural network)과 수문학적 이미지 (hydrological image)를 이용하여 강우 발생시 BOD 및 총인의 부하량 예측 모형을 개발하였다. 합성곱 신경망의 입력자료는 일반적으로 RGB (red, green, bule) 사진을 이용하는데, 이를 그래도 오염부하량 예측에 활용하는 것은 경험적 모형의 전제(독립변수와 종속변수의 관계)를 무너뜨리는 결과를 초래할 수 있다. 이에, 본 연구에서는 오염부하량이 수문학적 조건과 토지이용 등의 변수에 의해 결정된다는 인과관계를 만족시키고자 수문학적 속성이 내재된 수문학적 이미지를 합성곱 신경망의 훈련자료로 사용하였다. 수문학적 이미지는 임의의 유역에 대해 2차원 공간에서 무차원의 수문학적 속성을 갖는 grid의 집합으로 정의되는데, 여기서 각 grid의 수문학적 속성은 SCS 토양보존국(soil conservation service, SCS)에서 발표한 수문학적 토양피복형수 (curve number, CN)를 이용하여 산출한다. 합성곱 신경망의 구조는 2개의 Convolution Layer와 1개의 Pulling Layer가 5회 반복하는 구조로 설정하고, 1개의 Flatten Layer, 3개의 Dense Layer, 1개의 Batch Normalization Layer를 배열하고, 마지막으로 1개의 Dense Layer가 연결되는 구조로 설계하였다. 이와 함께, 각 층의 활성화 함수는 정규화 선형함수 (ReLu)로, 마지막 Dense Layer의 활성화 함수는 연속변수가 도출될 수 있도록 회귀모형에서 자주 사용되는 Linear 함수로 설정하였다. 연구의 대상지역은 경기도 가평군 조종천 유역으로 선정하였고, 연구기간은 2010년 1월 1일부터 2019년 12월 31일까지로, 2010년부터 2016년까지의 자료는 모형의 학습에, 2017년부터 2019년까지의 자료는 모형의 성능평가에 활용하였다. 모형의 예측 성능은 모형효율계수 (NSE), 평균제곱근오차(RMSE) 및 평균절대백분율오차(MAPE)를 이용하여 평가하였다. 그 결과, BOD 부하량에 대한 NSE는 0.9, RMSE는 1031.1 kg/day, MAPE는 11.5%로 나타났으며, 총인 부하량에 대한 NSE는 0.9, RMSE는 53.6 kg/day, MAPE는 17.9%로 나타나 본 연구의 모형은 우수(good)한 것으로 판단하였다. 이에, 본 연구의 모형은 일반 ANN 모형을 이용한 선행연구와는 달리 2차원 공간정보를 반영하여 오염부하량 모의가 가능했으며, 제한적인 입력자료를 이용하여 간편한 모델링이 가능하다는 장점을 나타냈다. 이를 통해 정부의 물관리 정책을 위한 의사결정 및 부족한 물관리 분야의 행정력에 도움이 될 것으로 생각된다.

• Education of Primary School Mathematics
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• v.26 no.3
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• pp.141-162
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• 2023

Recently, in school mathematics, classes using mathematical modeling are attracting attention to improve students' mathematical problem-solving skills. However, existing preceding studies have been conducted mainly on elementary, middle, and high school or in-service teachers, so it may be limited to apply the contents and results of the research as it is to pre-service teachers, who are future professors. Therefore, this study examined the school days' experiences of mathematical modeling for pre-service elementary school teachers. In addition, in order to provide a positive experience for mathematical modeling, mathematical modeling problem creation activities were conducted through group activities, and the results and their perceptions were examined. As a result of the study, elementary school preservice teachers had very little experience with mathematical modeling activities during their elementary, middle, and high school days. It was found that there is a deficiency in creating an appropriate mathematical modeling problem suitable for the level of elementary school students. In addition, it was found that they had a positive perception of mathematical modeling after participating in the study. Based on these results, implications for the training process for preservice teachers were suggested.

• 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.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.42-42
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• 2022

지금까지도 유역에서의 녹조 모니터링은 현장채수를 통한 점 단위 모니터링에 크게 의존하고 있어 기후, 유속, 수온조건 등에 따라 수체에 광범위하게 발생하는 녹조를 효율적으로 모니터링하고 대응하기에는 어려운 점들이 있어왔다. 또한, 그동안 제한된 관측 데이터로 인해 현장 측정된 실측 데이터 보다는 녹조와 관련이 높은 NDVI, FGAI, SEI 등의 파생적인 지수를 산정하여 원격탐사자료와 매핑하는 방식의 분석연구 등이 선행되었다. 본 연구는 녹조의 모니터링시 정확도와 효율성을 향상을 목표로 하여, 우선은 녹조 측정장비를 활용, 7000개 이상의 녹조 관측 데이터를 확보하였으며, 이를 바탕으로 동기간의 고해상도 위성 자료와 실측자료를 매핑하기 위해 다양한Machine Learning기법을 적용함으로써 그 효과성을 검토하고자 하였다. 연구대상지는 낙동강 내성천 상류에 위치한 영주댐 유역으로서 데이터 수집단계에서는 면단위 현장(in-situ) 관측을 위해 2020년 2~9월까지 4회에 걸쳐 7291개의 녹조를 측정하고, 동일 시간 및 공간의 Sentinel-2자료 중 Band 1~12까지 총 13개(Band 8은 8과 8A로 2개)의 분광특성자료를 추출하였다. 다음으로 Machine Learning 분석기법의 적용을 위해 algae_monitoring Python library를 구축하였다. 개발된 library는 1) Training Set과 Test Set의 구분을 위한 Data 준비단계, 2) Random Forest, Gradient Boosting Regression, XGBoosting 알고리즘 중 선택하여 적용할 수 있는 모델적용단계, 3) 모델적용결과를 확인하는 Performance test단계(R², MSE, MAE, RMSE, NSE, KGE 등), 4) 모델결과의 Visualization단계, 5) 선정된 모델을 활용 위성자료를 녹조값으로 변환하는 적용단계로 구분하여 영주댐뿐만 아니라 다양한 유역에 범용적으로 적용할 수 있도록 구성하였다. 본 연구의 사례에서는 Sentinel-2위성의 12개 밴드, 기상자료(대기온도, 구름비율) 총 14개자료를 활용하여 Machine Learning기법 중 Random Forest를 적용하였을 경우에, 전반적으로 가장 높은 적합도를 나타내었으며, 적용결과 Test Set을 기준으로 NSE(Nash Sutcliffe Efficiency)가 0.96(Training Set의 경우에는 0.99) 수준의 성능을 나타내어, 광역적인 위성자료와 충분히 확보된 현장실측 자료간의 데이터 학습을 통해서 조류 모니터링 분석의 효율성이 획기적으로 증대될 수 있음을 확인하였다.

• 재활복지
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• v.15 no.4
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• pp.27-47
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• 2011

The purpose of this research is to develop transition process and programmes for gently converting people with disabilities to local communities, through their empowerments. The methods used in the research were literature research, case studies on related programs, and expert interviews. The following shows the results. Firstly, the transition process for people with developmental disorders is exceedingly limited, and the process does not consider special attention needed for people with developmental disorders. Secondly, the postsecondary education programs for people with developmental disorders are being started as transition processes, however these programs need more connection with secondary schools. Thirdly, the primary factors which must be contemplated for University programs(for people with developmental disorders, after secondary education) are self-cognition and self-understanding. According to these results, we can suggest transition processes and programs within Universities for people with developmental disorders. (In Korea) Firstly, the postsecondary transition for people with developmental disorders requires a consideration of their characteristics, and mainstreaming education is also needed for their self-cognition and self-understanding. Considering this, the transition process within Universities can be an alternative. Secondly, tertiary educations within Universities for people with developmental disorders need to consider the following factors: ① The programs in Universities need to set up a support network. ② The door to program should be open to all students with developmental disorders within the Universities. ③ Organization of human resources must be systematized and connected, so that specialists within the Universities can participate in the postsecondary education programs for people with developmental disorders. ④ Inclusive learning activities must be under-taken, allowing students without disabilities to participate in the programs for students with developmental disorders.

• Korean Journal of School Psychology
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• v.11 no.1
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• pp.253-274
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• 2014

The present study classified groups based on latent profile of self-determination motivation(amotivation, external motivation, intrinsic motivation), and examined the determinants for each group. The data was collected through panel data of Korea Education Longitudinal Study(KELS), total 5,459 participants who answered questionnaires of self-determination motivation of two times both second grade of middle school and second grade of high school. To identify the change motivational type, standardized residual was conducted using SPSS 17.0., and the latent classes for the change of motivational type was investigated using M-Plus in the frame work of Latent Profile Analysis(LPA). The results indicated that five groups(increase of self-determination, self-determination maintenance, self-determination developmental delay, elf-determination confusion, decrease of self-determination group) were classified based on latent profile. In addition, parental control, academic self-concept, teacher-student relationship, test anxiety, avoidance orientation, gender, father's education, and income were significantly related to each group. Lastly, the implications for directions of the adolescent counseling, limitations and future research are discussed.

• Journal of The Korean Association For Science Education
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• v.29 no.6
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• pp.693-711
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• 2009

One of the most important objectives in science education is to develop students' science literacy. The purpose of this study is to analyze the relevance between biology instructional objectives in the 7th curriculum taught in elementary and secondary schools. For this study, 7 major parts in each grade were analyzed including cell, the form and function of plants, the form and function of animals, genetics, diversity, evolution, ecology, and environment. The strand map of instructional objectives is completed that represents the relation between the objectives. The summary of the results from this study is as follows. First, the concept about cells is not fully covered in lower grades including elementary schools. While the concept of energy metabolism is repeatedly covered, there is no concept of energy covered in learning the concept of energy metabolism in elementary schools. Second, the textbooks in elementary and middle schools have main concepts about the form and function of plants while those in high schools don't. The concept related to the part of the form and function of animals is repeatedly involved in the curriculum throughout the elementary, middle, and high schools. Third, the concepts such as genetics and evolution are involved in higher grades since these concepts are abstract ones. The part of genetics and evolution as well as diversity has no connection between grades in schools, so the development of "notion between" is necessary to relate these concepts with each other. Fourth, the 4 parts of diversity, ecology and environment, evolution, and the form and function of plants are covered in limited grade levels. The results of the relevance of gene in lesson goals will play an important rein as the primary material in developing the connection between textbooks in which lesson goals are closely related to each other throughout all grade levels in elementary, middle and high schools.

• The Journal of Sustainable Design and Educational Environment Research
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• v.23 no.2
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• pp.1-10
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• 2024

This study presents a model for educational planning based on user participatory design for the purposes of curriculum development and educational space innovation. It reviewed previous research and practices related to educational space innovation, educational planning processes, and user participation design and suggested a draft model. This model was applied in the renovation project of an elementary school, and the problems encountered during the application were reflected upon and used to improve the model. The final model comprises four phases. Phase 1 is an initial exploratory phase foruser participation, where educational planners and users form a shared perspective regarding the future of education. Phase 2 is a needs-analysis phase for the transition to future education, which focuses on setting the overall direction of the school-level curriculum. Phase 3 specifies the direction of future school curricula and identifies needs for educational spaces. Finally, Phase 4 focuses on the interaction between educational and space planners. Based on the above discussion, the study discussed the benefits and limitations of this educational planning model for school space innovation.