• 방사성폐기물학회지
• /
• 제2권1호
• /
• pp.35-40
• /
• 2004

Final disposal of radioactive waste generated from Nuclear Power Plant (NPP) requires the detailed information about the characteristics and the quantities of radionuclides in waste package. Most of these radionuclides are difficult to measure and expensive to assay. Thus it is suggested to the indirect method by which the concentration of the Difficult-to-Measure (DTM) nuclide is estimated using the correlations of concentration - it is called the scaling factor - between Easy-to-Measure (Key) nuclides and DTM nuclides with the measured concentration of the Key nuclide. In general, the scaling factor is determined by the log mean average (LMA) method and the regression method. However, these methods are inadequate to apply to fission product nuclides and some activation product nuclides such as 14$^{C}$ and 90$^{Sr}$ . In this study, the artificial neural network (ANN) method is suggested to improve the conventional SF determination methods - the LMA method and the regression method. The root mean squared errors (RMSE) of the ANN models are compared with those of the conventional SF determination models for 14$^{C}$ and 90$^{Sr}$ in two parts divided by a training part and a validation part. The SF determination models are arranged in the order of RMSEs as the following order: ANN model

• Spatial Information Research
• /
• 제15권3호
• /
• pp.189-202
• /
• 2007

지자체 GIS 정보화가 확산되어감에 따라 구축된 공간정보의 활용확산, 타 정보와의 연계 등의 요구가 증대되고 있다. 특히 지자체 행정업무의 70-80%가 공간정보와 연계되어 있는 만큼, 지자체 GIS 통합 연계가 지자체 정보화의 핵심으로 부각되고 있다. 이에 본 연구는 현 지자체GIS 통합 연계 현황과 기존연구에서의 지자체 GIS 통합 연계 이슈사항을 파악하고, 이를 기반으로 지자체 GIS 통합 연계 이슈정립 및 해당이슈를 해결하기 위한 지자체 GIS 통합 연계 고도화 모델을 제시하였다. 지자체 GIS 통합 연계 고도화모델은 지자체 지리정보 담당부서 중심의 통합연계에서 확대하여, 지자체 전 부서 및 국가적 차원에서의 통합연계를 고려한 모델이다. 지자체 GIS 통합연계 고도화 모델을 위한 추진전략으로 자료공유방안, 지자체GIS 공통기반 데이터정비, 지자체 GIS 통합DB구축 및 연계구조 기반의 아키텍쳐 개선, 시스템 및 DB 구축 및 개선, GIS DB 통합인프라 표준정비, 지자체 GIS 통합연계 정보화 기반조성이라는 전략을 제시하였다. 결론으로, 제시된 모델의 구현을 위해선 협업의 개념이 바탕이 된 제도적인 뒷받침이 우선시되어야 함이 강조되었다.

• 인터넷정보학회논문지
• /
• 제22권4호
• /
• pp.13-28
• /
• 2021

강화학습은 한 환경에서 에이전트가 정책에 따라 액션을 취하고 보상 함수를 통해 액션을 평가 및 정책 최적화 과정을 반복하는 Closed-Loop 구조로 이루어진 알고리즘이다. 이러한 강화학습의 주요 장점은 액션의 품질을 평가하고 정책을 지속적으로 최적화 하는 것이다. 따라서, 강화학습은 지능형 시스템, 자율제어 시스템 개발에 효과적으로 활용될 수 있다. 기존의 강화학습은, 단일 정책, 단일 보상함수 및 비교적 단순한 정책 업데이트 기법을 제한적인 문제에 대해 제시하고 적용하였다. 본 논문에서는 구성요소의 복수성을 지원하는 확장된 강화학습 모델을 제안한다. 제안되는 확정 강화학습의 주요 구성 요소들을 정의하고, 그들의 컴퓨팅 모델을 포함하는 정형 모델을 제시한다. 또한, 이 정형모델을 기반으로 시스템 개발을 위한 설계 기법을 제시한다. 제안한 모델을 기반으로 자율 최적화 자동차 내비게이터 시스템에 적용 및 실험을 진행한다. 제시된 정형 모델과 설계 기법을 적용한 사례연구로, 복수의 자동차들이 최적 목적지에 단 시간에 도착할 수 있는 진화된 내비게이터 시스템 설계 및 구현을 진행한다.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2004년도 ICCAS
• /
• pp.2005-2010
• /
• 2004

As robots become more prevalent in human daily life, situations requiring interaction between humans and robots will occur more frequently. Therefore, human-robot interaction (HRI) is becoming increasingly important. Although robotics researchers have made many technical developments in their field, intuitive and easy ways for most common users to interact with robots are still lacking. This paper introduces a new approach to enhance human-robot interaction using a semantic symbol language and proposes a method to acquire the intentions of robot users. In the proposed approach, each semantic symbol represents knowledge about either the environment or an action that a robot can perform. Users'intentions are expressed by symbolized multimodal information. To interpret a users'command, a probabilistic approach is used, which is appropriate for interpreting a freestyle user expression or insufficient input information. Therefore, a first-order Markov model is constructed as a probabilistic model, and a questionnaire is conducted to obtain state transition probabilities for this Markov model. Finally, we evaluated our model to show how well it interprets users'commands.

• Smart Structures and Systems
• /
• 제32권2호
• /
• pp.123-133
• /
• 2023

This paper proposes a thermography-based coating thickness estimation method for steel structures using model-agnostic meta-learning. In the proposed method, a halogen lamp generates heat energy on the coating surface of a steel structure, and the resulting heat responses are measured using an infrared (IR) camera. The measured heat responses are then analyzed using model-agnostic meta-learning to estimate the coating thickness, which is visualized throughout the inspection surface of the steel structure. Current coating thickness estimation methods rely on point measurement and their inspection area is limited to a single point, whereas the proposed method can inspect a larger area with higher accuracy. In contrast to previous ANN-based methods, which require a large amount of data for training and validation, the proposed method can estimate the coating thickness using only 10- pixel points for each material. In addition, the proposed model has broader applicability than previous methods, allowing it to be applied to various materials after meta-training. The performance of the proposed method was validated using laboratory-scale and field tests with different coating materials; the results demonstrated that the error of the proposed method was less than 5% when estimating coating thicknesses ranging from 40 to 500 ㎛.

• 유통과학연구
• /
• 제20권6호
• /
• pp.75-86
• /
• 2022

Purpose: This research aims to provide empirical evidence on the impact of digital literacy on behavioural intention regarding using technology for distribution of higher education. Design, Methodology, and Approach: Quantitative analysis was carried out using Covariance-Based Structural Equation Model with data collected from 901 students who fully experienced 2-year study online at different universities in Vietnam. The structural model was built with digital literacy as the primary indicator and other variables were included based on modified version of Unified Theory of Acceptance and Use of Technology (UTAUT2) by adopting performance expectancy, effort expectancy, social influence, habit, and hedonic motivation variables specifically for education sector. Self-efficacy was added to eliminate possible bias in technology acceptance. Results: From the results of model estimation, digital literacy presented positive impact on the online distribution of higher education in Vietnam. The mediating effects of various indicators such as performance expectancy, effort expectancy, social influence, habit, hedonic motivation, and self-efficacy are significantly determined by research model. Conclusion: The higher level of digital literacy of the students, the more likely that they will use technology in higher education study, especially online learning. Additionally, the mediating effects of indicators from the UTAUT2 theoretical model were also evident to be positively significant.

• Smart Structures and Systems
• /
• 제31권6호
• /
• pp.561-571
• /
• 2023

Ensuring the safety of a structure necessitates that repairs are carried out based on accurate inspections and records of damage information. Traditional methods of recording damage rely on individual paper-based documents, making it challenging for inspectors to accurately record damage locations and track chronological changes. Recent research has suggested the adoption of building information modeling (BIM) to record detailed damage information; however, localizing damages on a BIM model can be time-consuming. To overcome this limitation, this study proposes a method to automatically localize damages on a BIM model in real-time, utilizing consecutive images and measurements from an inertial measurement unit in close proximity to damages. The proposed method employs a visual-inertial odometry algorithm to estimate the camera pose, detect damages, and compute the damage location in the coordinate of a prebuilt BIM model. The feasibility and effectiveness of the proposed method were validated through an experiment conducted on a campus building. Results revealed that the proposed method successfully localized damages on the BIM model in real-time, with a root mean square error of 6.6 cm.

• 제어로봇시스템학회논문지
• /
• 제20권12호
• /
• pp.1209-1216
• /
• 2014

This paper copes with control design for unmanned aerial vehicle transportation system. Moving pendulum dynamics of slung-load system is derived using two methods: Udwadia-Kalaba equation and Newtonian approach. PID controller is applied to Udwadia-Kalaba equation model for structural consistency and linear quadratic Gaussian / Loop Transfer Recovery (LQG/LTR) technique is employed for Newtonian model with minimal state-space realization. Characteristics of PID and LQG/LTR controller are compared, and two controllers are combined to compensate the drawbacks of each other. Numerical simulation is set for two cases and conducted to evaluate performance of designed controllers. The result proves that combination of LQG/LTR and PID control performs stable and robust.

• 한국지능시스템학회:학술대회논문집
• /
• 한국퍼지및지능시스템학회 2003년도 ISIS 2003
• /
• pp.187-190
• /
• 2003

Many manufacturing companies consider the integrated and concurrent scheduling because they need the global optimization technology that could manufacture various products more responsive to customer needs. In this paper, we propose an advanced scheduling model to generate the schedules considering resource constraints and precedence constraints in make-to-order (MTO) manufacturing environments. Precedence of work- in-process(WIP) and resources constraints have recently emerged as one of the main constraints in advanced scheduling problems. The advanced scheduling problems is formulated as a multiobjective mathematical model for generating operation schedules which are obeyed resources constraints, alternative workstations of operations and the precedence constraints of WIP in MTO manufacturing. For effectively solving the advanced scheduling problem, the multi-objective hybrid genetic algorithm (m-hGA) is proposed in this paper. The m-hGA is to minimize the makespan, total flow time of order, and maximum tardiness for each order, simultaneously. The m-hGA approach with local search-based mutation through swap mutation is developed to solve the advanced scheduling problem. Numerical example is tested and presented for advanced scheduling problems with various orders to describe the performance of the proposed m-hGA.

• 천문학회보
• /
• 제35권1호
• /
• pp.71.1-71.1
• /
• 2010

We present the FUV continuum map of The Taurus-Auriga-Perseus complex, which is one of the largest local association of dark clouds. The map is well consistent with the dust extinction and the CO emission map of the T-P-A region. The region is divided into 3 sub-regions by diffuse FUV intensities and the spectra of each region imply that the radiation field due to the Per OB2-association can be a main source of the H2 fluorescent emission of the nearby cloud region. We used the PDR H2 model, named CLOUD, developed by van Dishoeck &Black for the sake of comparing our results to the H2 model.