• 한국세라믹학회지
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• 제43권1호
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• pp.1-3
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• 2006

Well-shaped NaA zeolite cubic crystals of a large size of $5-7{\mu}m$ were synthesized by a hydrothermal method in a mother solution having a $3.55Na_2O:Al_2O_3:1.6SiO_2:593\~2000H_2O$ composition. Thermal treatment of NaA zeolite crystals resulted in the formation of a crystalline phase of $NaAlSiO_4-Camegeite$ between 800 and $900^{\circ}C$. Even at $1000^{\circ}C,\;NaAlSiO_4$ phase was found as a major product. Environmental Scanning Electron Microscopy (ESEM), High Resolution Transmission Electron Microscopy (HRTEM), X-Ray powder Diffraction (XRD), Fourier Transform Infrared (FT-IR) spectroscopy, and DTA/TGA and BET analyses were used to characterize the initial materials and the obtained products after various heat treatments.

• 대한기계학회논문집
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• 제8권6호
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• pp.584-590
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• 1984

본 연구에서는 Luh, Walker와 Paul이 제안한 Newton Euler 방법에 따라 토오 크를 계산하였고, 임으로 로봇을 선택하여 시뮬레이션 크로그램을 적용하였다.

• 에너지공학
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• 제19권1호
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• pp.1-7
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• 2010

본 정책총설은 세계적인 에너지 수급의 불안정과 온실가스 감축에 대한 규제에 대응하여 안정적 경제성장과 환경보호를 달성할 수 있는 대안을 제시하고 있다. 이를 위해 에너지 수급전체를 최적화하는 에너지체인(energy chain) 접근방식을 채택하고 있다. 에너지체인에 걸쳐 저탄소 친환경 에너지기술의 개발 및 산업화, 주력산업의 저탄소 친환경화, 에너지 효율성의 제고, 에너지원의 확보, 그리고 이들 정책간 정책군의 형성 등을 제시하고 있다.

• 센서학회지
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• 제23권1호
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• pp.66-71
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• 2014

Vision is the most important sensing capability for both men and sensory smart machines, such as intelligent robots. Sensed real 3D world and its 2D camera image can be related mathematically by a process called camera calibration. In this paper, we present a novel linear solution of camera calibration. Unlike most existing linear calibration methods, the proposed technique of this paper can identify camera parameters explicitly. Through the step-by-step procedure of the proposed method, the real physical elements of the perspective projection transformation matrix between 3D points and the corresponding 2D image points can be identified. This explicit solution will be useful for many practical 3D sensing applications including robotics. We verified the proposed method by using various cameras of different conditions.

• Journal of Information Processing Systems
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• 제12권4호
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• pp.661-680
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• 2016

The vehicle license plate recognition (VLPR) system analyzes and monitors the speed of vehicles, theft of vehicles, the violation of traffic rules, illegal parking, etc., on the motorway. The VLPR consists of three major parts: license plate detection (LPD), license plate character segmentation (LPCS), and license plate character recognition (LPCR). This paper presents an efficient method for the LPCS and LPCR of Korean vehicle license plates (LPs). LP tilt adjustment is a very important process in LPCS. Radon transformation is used to correct the tilt adjustment of LP. The global threshold segmentation method is used for segmented LP characters from two different types of Korean LPs, which are a single row LP (SRLP) and double row LP (DRLP). The cross-correlation matching method is used for LPCR. Our experimental results show that the proposed methods for LPCS and LPCR can be easily implemented, and they achieved 99.35% and 99.85% segmentation and recognition accuracy rates, respectively for Korean LPs.

• 정보관리학회지
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• 제20권1호
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• pp.321-339
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• 2003

학술 연구정보의 지식활용을 위한 노력으로 국내 환경공학 R&D 정보의 지식전환 가능성을 조사하였고 그 가능성에 따라 지식관리시스템 개발을 위한 고려사항과 접근법을 제시하였다. 연구범위는 정보자원자체의 현황 정보 기술 인프라, 지식기반, 그리고 지식활용 영역의 4개영역으로 구성되었고 각 영역은 세부항목으로 구분되어 총 103개 지식관리시스템의 전환가능성이 조사, 분석되었다. 진단된 결과를 중심으로 연구소 연계 프로젝트의 공동작업을 수행하고 그 진행에 따라 발생하는 연구과 정상의 문제해결과 지식전환 시에 예상 가능한 시행착오를 최소화하는 프로세스 중심의 지식관리시 스템 개발방안을 제시하였다.

• 한국가구학회지
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• 제17권3호
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• pp.45-55
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• 2006

The change of consumers' lifestyles causes frequent study on beds along with growth of economy, improvement of education and increase of dwelling in new towns and nuclear family. Beds are frequently developed in recent years since consumers' lifestyles increasingly change caused by transformation of types of dwelling, influence of western lifestyle, and increase uses of a bed. Also, this transformation causes needs for research on bed designs. A Bed is an essential item in a life since people spend one third of a day in Also, in contemporary, the ages of consumers are varied from infants to seniors. The study examines the importance of beds which playa major role in households. Moreover, the purpose of this study of beds focused on surface materials, colors, and designs is suggesting bases for future developments.

• 한국표면공학회지
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• 제32권2호
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• pp.100-108
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• 1999

The microstructure and corrosion properties of Al-Si diffusion coated PWA1426 alloy have been investigated. Experimental variables are included temperatures of heat-treatment and coating thickness. The microstructure of coated layer and corrosion properties were analysed by SEM, EDS and hot corrosion test. Two major processes have been found to contribute to microstructural changes in the coating. These are, firstly, the transformation of the NiAl to other $Ni_2Al_3$-based phase and secondly, the precipitation of Cr containing phases. Specimens heat treated at $1080^{\circ}C$ showed superior corrosion resistance to heat treated at $880^{\circ}C$. These increase in life was attributed to the transformation of NiAl and increased coating thickness of PWA1426 alloy.

• International Journal of Internet, Broadcasting and Communication
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• 제11권3호
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• pp.1-7
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• 2019

Previously, parallel computing was mainly used in areas requiring high computing performance, but nowadays, multicore CPUs and GPUs have become widespread, and parallel programming advantages can be obtained even in a PC environment. Various parallel programming frameworks using multicore CPUs such as OpenMP and PPL have been announced. Nvidia and AMD have developed parallel programming platforms and APIs for program developers to take advantage of multicore GPUs on their graphics cards. In this paper, we develop digital image transformation programs that runs on each of the major parallel programming frameworks, and measure the execution time. We analyze the characteristics of each framework through the execution time comparison. Also a constant K indicating the ratio of program execution time between different parallel computing environments is presented. Using this, it is possible to predict rough execution time without implementing a parallel program.

• Communications for Statistical Applications and Methods
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• 제31권1호
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• pp.105-127
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• 2024

We propose recurrent neural network (RNN) methods for forecasting realized volatility (RV). The data are RVs of ten major stock price indices, four from the US, and six from the EU. Forecasts are made for relative ratio of adjacent RVs instead of the RV itself in order to avoid the out-of-scale issue. Forecasts of RV ratios distribution are first constructed from which those of RVs are computed which are shown to be better than forecasts constructed directly from RV. The apparent asymmetry of RV ratio is addressed by the Piecewise Min-max (PM) normalization. The serial dependence of the ratio data renders us to consider two architectures, long short-term memory (LSTM) and gated recurrent unit (GRU). The hyperparameters of LSTM and GRU are tuned by the nested cross validation. The RNN forecast with the PM normalization and ratio transformation is shown to outperform other forecasts by other RNN models and by benchmarking models of the AR model, the support vector machine (SVM), the deep neural network (DNN), and the convolutional neural network (CNN).