• The Journal of Korea Institute of Information, Electronics, and Communication Technology
• /
• v.6 no.4
• /
• pp.238-242
• /
• 2013

We consider the problem of constructing observers for nonlinear systems with unknown inputs. Connectionist networks, also called neural networks, have been broadly applied to solve many different problems since McCulloch and Pitts had shown mathematically their information processing ability in 1943. In this thesis, we present a genetic neuro-control scheme for nonlinear systems. Our method is different from those using supervised learning algorithms, such as the backpropagation (BP) algorithm, that needs training information in each step. The contributions of this thesis are the new approach to constructing neural network architecture and its training.

• Proceedings of the Korean Information Science Society Conference
• /
• 2002.10d
• /
• pp.391-393
• /
• 2002

최근 가상교육에서 학습 기술의 상호 운용성을 기반으로 한 표준화의 필요성을 인식하고 여러 국제표준기관을 통해서 기반 환경과 컨텐트 명세 및 활용에 대한 표준화 작업이 이루어지고 있다. 이로 인해 e-learning 분야에서는 국제표준을 소개하고 체제적으로 AICC(Aviation Industry CBT Committee), IMS(Instructional Management Systems) Global Learning Consortium, ADL(Advanced Distributed Learning)을 중심으로 진행되어 오고 있다. 특히, 미래의 진보적인 e-learning 환경 개발로, 기능별 5계층으로 구성된 LTSA(Learning Technology Standard Architecture)를 제정하고 이를 통한 개발을 지원하고 있다. 하지만, 이는 시스템 구성요소를 정의한 계층 3의 경우 데이터 흐름 모델로 작성되어 현재 개발 수준과 일치하지 않는 문제점을 가지는 모델로 인정한다. 본 논문에서는 표준 모델링 언어인 UML(Unified Modeling Language)을 통해 모델을 재정의하고, 각 프로세스별 단계를 메타모델로 제시하여 개발과 아키텍처의 이해에 대한 문제점을 해결하고자 한다. 또한, 재정의된 모델을 기반으로 e-learning 지원을 위한 분석, 설계 프로세스를 정의하여 이에 대한 사례를 제시한다. 이는 아키텍처를 기반으로 한 메타모델과 프로세스를 통한 교육영역의 질의 응답 학습 도구인 QALT(Query-Answer Learning Tool)에 적용한다. 모델의 재정의로 아키텍처의 이해성 및 이를 기반으로 하는 교육용 애플리케이션 개발의 용이성의 증대를 기대할 수 있으며, 모델의 재사용성을 보장할 수 있다.

• International Journal of Naval Architecture and Ocean Engineering
• /
• v.12 no.1
• /
• pp.428-439
• /
• 2020

The continuous development of information and communication technologies has resulted in an exponential increase in data. Consequently, technologies related to data analysis are growing in importance. The shipbuilding industry has high production uncertainty and variability, which has created an urgent need for data analysis techniques, such as machine learning. In particular, the industry cannot effectively respond to changes in the production-related standard time information systems, such as the basic cycle time and lead time. Improvement measures are necessary to enable the industry to respond swiftly to changes in the production environment. In this study, the lead times for fabrication, assembly of ship block, spool fabrication and painting were predicted using machine learning technology to propose a new management method for the process lead time using a master data system for the time element in the production data. Data preprocessing was performed in various ways using R and Python, which are open source programming languages, and process variables were selected considering their relationships with the lead time through correlation analysis and analysis of variables. Various machine learning, deep learning, and ensemble learning algorithms were applied to create the lead time prediction models. In addition, the applicability of the proposed machine learning methodology to standard work hour prediction was verified by evaluating the prediction models using the evaluation criteria, such as the Mean Absolute Percentage Error (MAPE) and Root Mean Squared Logarithmic Error (RMSLE).

• Journal of Ocean Engineering and Technology
• /
• v.34 no.3
• /
• pp.167-179
• /
• 2020

Recently, the increasing importance of artificial intelligence (AI) technology has led to its increased use in various fields in the shipbuilding and marine industries. For example, typical scenarios for AI include production management, analyses of ships on a voyage, and motion prediction. Therefore, this study was conducted to predict a response amplitude operator (RAO) through AI technology. It used a neural network based on one of the types of AI methods. The data used in the neural network consisted of the properties of the vessel and RAO values, based on simulating the in-house code. The learning model consisted of an input layer, hidden layer, and output layer. The input layer comprised eight neurons, the hidden layer comprised the variables, and the output layer comprised 20 neurons. The RAO predicted with the neural network and an RAO created with the in-house code were compared. The accuracy was assessed and reviewed based on the root mean square error (RMSE), standard deviation (SD), random number change, correlation coefficient, and scatter plot. Finally, the optimal model was selected, and the conclusion was drawn. The ultimate goals of this study were to reduce the difficulty in the modeling work required to obtain the RAO, to reduce the difficulty in using commercial tools, and to enable an assessment of the stability of medium/small vessels in waves.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2015.04a
• /
• pp.1015-1017
• /
• 2015

본 연구는 서로 다른 문화간에 e-Learning과 같은 학습 시스템을 제공할 때, 학습 제공자의 문화적 차이에 의한 비언어적 행동이 학습자에게 미치는 영향에 대해 다루고 있다. 지금까지 사회언어학적인 관점에서 서로 다른 문화간의 언어행동에 관한 연구는 있었지만 비디오 학습이나 웹과 같이 원거리에서 이루어지는 학습 지원 시스템에서의 언어행동에 관한 연구는 없었다. 본 연구에서는 행동언어학적인 관점에서 이루어진 연구를 바탕으로, 한국인과 일본인을 대상으로 하여 실제 강의가 이루어지는 동안 언어행동의 문화적 차이가 미치는 영향과 그 결과를 검증했다.

• Journal of Information Technology Applications and Management
• /
• v.27 no.3
• /
• pp.19-36
• /
• 2020

The Internet of things (IoT) is a system of interrelated computed devices, digital machines and any physical objects which are provided with unique identifiers and the potential to transmit data to people or machine (M2M) without requiring human interaction. IoT devices can be used to monitor and control the electrical and electronic systems used in different fields like smart home, smart city, smart healthcare and etc. In this study we introduce four imaginary IoT devices as a learning support assistants according to students' dominant learning styles measured by Honey and Mumford Learning Styles: Activists, Reflectors, Theorists and Pragmatists. This research emphasizes the association between students' strong learning styles and a preference to appropriate IoT devices with specific characteristics. Moreover, different levels of IoT devices' architecture are clearly explained in this study where all the artificial devices are designed based on this structure. Data analysis of experiment were measured by the use of chi square test for association and research results showed the statistical significance of the estimated model and the impacts of each category over the model where we finally got accurate estimates for our research variables. This study revealed the importance of considering the students' dominant learning styles before inventing a new IoT device.

• International Journal of Computer Science & Network Security
• /
• v.21 no.11
• /
• pp.216-222
• /
• 2021

Advances in technology have given educators a tool to empower them to assist with developing the best possible human resources. Teachers at universities prefer to use more modern technological advances to help them educate their students. This opens up a necessity to research the capabilities of cloud-based learning services so that educational solutions can be found among the available options. Based on that, this essay looks at models and levels of deployment for the e-learning cloud architecture in the education system. A project involving educators explores whether gement Systems (LMS) can function well in a collaborative remote learning environment. The study was performed on how Blackboard was being used by a public institution and included research on cloud computing. This test examined how Blackboard Learn performs as a teaching tool and featured 60 participants. It is evident from the completed research that computers are beneficial to student education, especially in improving how schools administer lessons. Convenient tools for processing educational content are included as well as effective organizational strategies for educational processes and better ways to monitor and manage knowledge. In addition, this project's conclusions help highlight the advantages of rolling out cloud-based e-learning in higher educational institutions, which are responsible for creating the integrated educational product. The study showed that a shift to cloud computing can bring progress to educational material and substantial improvement to student academic outcomes, which is related to the increased use of better learning tools and methods.

• Journal of Information Technology and Architecture
• /
• v.10 no.3
• /
• pp.371-378
• /
• 2013

Video-demand learning through E-learning continuously increases on these days. However, not all video-demand learning systems can be utilized properly. When students study by education videos not matched to level of their own, it is possible for them to lose interest in learning. It causes to reduce the learning efficiency. In order to solve the problem, we need to develop a recommendation system which recommends customized education videos according the study levels of students. In this paper, we estimate the study level based on the history of students' watching behaviors such as average watching time, skipping and rewinding of videos. In the experimental section, we demonstrate our recommendation system using real students' video watching history to show that our system is feasible in a practical environment.

• Proceedings of the Korean Society for Bioinformatics Conference
• /
• 2005.09a
• /
• pp.202-205
• /
• 2005

Cell phenotypes are determined by the concerted activity of thousands of genes and their products. This activity is coordinated by a complex network that regulates the expression of genes. Understanding this organization is crucial to elucidate cellular activities, and many researches have tried to construct gene regulatory networks from mRNA expression data which are nowadays the most available and have a lot of information for cellular processes. Several computational tools, such as Boolean network, Qualitative network, Bayesian network, and so on, have been applied to infer these networks. Among them, Bayesian networks that we chose as the inference tool have been often used in this field recently due to their well-established theoretical foundation and statistical robustness. However, the relative insufficiency of experiments with respect to the number of genes leads to many false positive inferences. To alleviate this problem, we had developed the algorithm of MONET(MOdularized NETwork learning), which is a new method for inferring modularized gene networks by utilizing two complementary sources of information: biological annotations and gene expression. Afterward, we have packaged and improved MONET by combining dispersed functional blocks, extending species which can be inputted in this system, reducing the time complexities by improving algorithms, and simplifying input/output formats and parameters so that it can be utilized in actual fields. In this paper, we present the architecture of MONET system that we have improved.

• Journal of the Earthquake Engineering Society of Korea
• /
• v.28 no.4
• /
• pp.193-203
• /
• 2024

Existing reinforced concrete (RC) building frames constructed before the seismic design was applied have seismically deficient structural details, and buildings with such structural details show brittle behavior that is destroyed early due to low shear performance. Various reinforcement systems, such as fiber-reinforced polymer (FRP) jacketing systems, are being studied to reinforce the seismically deficient RC frames. Due to the step-by-step modeling and interpretation process, existing seismic performance assessment and reinforcement design of buildings consume an enormous amount of workforce and time. Various machine learning (ML) models were developed using input and output datasets for seismic loads and reinforcement details built through the finite element (FE) model developed in previous studies to overcome these shortcomings. To assess the performance of the seismic performance prediction models developed in this study, the mean squared error (MSE), R-square (R²), and residual of each model were compared. Overall, the applied ML was found to rapidly and effectively predict the seismic performance of buildings according to changes in load and reinforcement details without overfitting. In addition, the best-fit model for each seismic performance class was selected by analyzing the performance by class of the ML models.