• 제어로봇시스템학회논문지
• /
• 제21권5호
• /
• pp.453-458
• /
• 2015

We presented a quad-rotor controlling algorithm design by using sensor fusion in this paper. The controller design technique was performed by a PD controller with a Kalman filter and compensation algorithm for increasing the stability and reliability of the quad-rotor attitude. In this paper, we propose an attitude estimation algorithm for quad-rotor based sensor fusion by using the Kalman filter. For this reason, firstly, we studied the platform configuration and principle of the quad-rotor. Secondly, the bias errors of a gyro sensor, acceleration and geomagnetic sensor are compensated. The measured values of each sensor are then fused via a Kalman filter. Finally, the performance of the proposed algorithm is evaluated through experimental data of attitude estimation. As a result, the proposed sensor fusion algorithm showed superior attitude estimation performance, and also proved that robust attitude estimation is possible even in disturbance.

• 한국수산과학회지
• /
• 제36권2호
• /
• pp.107-112
• /
• 2003

Effect of PCBs on the skin and gill development of olive flounder, Paralichthys olivaceus were investigated by histological methodology and morphometric data. The olive flounder were exposed to limit concentration of effulent of PCBs (3.0 ${\mu}g/L$) for 60 days. Skin development can be classified into four stages: SSEL (simple squamous epithelial layer), MCA (mucous cell appearance) & CCA (club cell appearance) DLA (dermal layer appearance), and SEL (startification of epidermal layer) stages. Gill development had five stages: GFA (gill filament appearance), IGFE (identification of early gill filament epithelial cell) MCA (mucous cell appearance), PCA (pillar cell appearance), and FGL (formation of gill lamella) stages. The periods of structural completion of skin and gill were 22-30 days and 23-30 days after hatching in the exposure group respectively. The process of development of skin and gill of the exposure group was very similar to that of the control group. Therefore, PCBs (3 ${\mu}g/L$) have no influence on the development of skin and gill in the larval stage of olive flounder.

• International Journal of Concrete Structures and Materials
• /
• 제18권3E호
• /
• pp.145-150
• /
• 2006

An experiment with the objective of providing guidelines for joint depth determination and timing of contraction joint sawcutting to avert uncontrolled cement concrete pavement cracking has been conducted. Theoretical analysis and laboratory tests were performed to help in understanding and analyzing the field observation. Using two-dimensional elastic fracture mechanics, the influence of several parameters on crack propagation was delineated by a parametric study, involving initial notch ratio, joint spacing, Young's modulus and thermal expansion coefficient of concrete, temperature gradient, and modulus of subgrade reaction. Bimaterials made of rock plus cement mortar and rock plus polymer mortar were applied to the concrete in a field test section, and they were subjected to fracture tests. These tests have shown that fracture mechanics is a powerful tool not only in judging the quality of the jointed cement concrete pavement but also in providing a criterion for crack propagation and delamination. Based on fracture mechanics, a method is proposed to determine the joint depth, sawcut timing, and spacing of the jointed cement concrete pavement. This method has successfully been applied to a test section in Seohaean expressway. This study also summarizes the research results obtained from a field test for jointed plain concrete pavement, which was also carried out on the Seohaean expressway.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2006년도 춘계학술대회논문집
• /
• pp.759-763
• /
• 2006

The World Health Organization(WHO) has recommended population of sleep disturbance as one of the environmental health indicators. But the percentage of respondents who felt highly sleep disturbed, that is, %HSD can???thave application to sleep disturbance from instantaneous noise. Therefore, this study has been carried out to present the technique for assessing sleep disturbance on instantaneous noise quantitatively. The study of sleep disturbance on night time instantaneous railway noise has been undertaken. Noise monitor has been in operation from 22 hours to 7 hours during 6 nights at 12 locations. To assess instantaneous noise induced sleep disturbance, it was decided to measure body movement by actiwatch. %motility was used as indicators of sleep disturbance. %motility is the expected value of probability of motility value during 7 epochs (105s) of any noise event. The measures of instantaneous motility have been related to measures of instantaneous railway noise events. The relationship shows that %motility is a good predictor for assessing sleep disturbance and Korean is more sensitive to noise than European although the railway noise have been considered in this study. This study can be extended to assessing long-term sleep disturbance and give a guideline far policy decision.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2006년도 영호남 합동 학술대회 및 춘계학술대회 논문집 센서 박막 기술교육
• /
• pp.49-51
• /
• 2006

Ternary chalcopyrite $CuInS_2$ thin film material is very promising for photovoltaic. Power generation because of its excellent optical and semiconductor properties, $CuInS_2$ thin films were performed from S/In/Cu/SLG stacked elemental layer (SEL) method with post annealing treatment. $CuInS_2$ thin films were appeared from 0.84 to 1.27 of Cu/In composition ratio and sulfur composition ratios of $CuInS_2$ thin films fabricated. Analysis of the optical energy band gap of $CuInS_2$ value of l.5eV interior and exterior.

• 한국동물학회지
• /
• 제35권4호
• /
• pp.456-465
• /
• 1992

The 94 KDa glucose-resulsted Protein (SH 94), one of stress Proteins, is a Ca2+-binding protein in the endoplasmic reticulum (ER). In this study, the possible effect of Ca2+ on the native conformation of grp 94 was examined. When the purified grp 94 was analyzed by Sel filtration in the presence of either EGTA or CaCl2, it was eluted with apparent molecular weight (MW) of 100 KDa in both cases. When similarly analyzed with microtome or cell Ivsate, however, srp 94 was eluted with apparent IW of 200 KDa in the presence of E6TA, while with apparent MW of 100 KDa in the presence of CaCl2, indicating possible association of grp 94 with one or more other proteins in the absence of CaCl2. Consequently, immunoprecipitation with anti-grp 94 was carried out to determine which proteins specifically interact with grp 94. It is sho%un that srp 94 may interact, in a Ca2+_dependent manner. with other proteins including BiP (grp 78) which is also a stress protein in the ER.

• 한국CDE학회논문집
• /
• 제2권2호
• /
• pp.77-84
• /
• 1997

This paper is concerning the development of multiple neural networks system of problem domains where the complete input space can be decomposed into several different regions, and these are known prior to training neural networks. We will adopt oblique decision tree to represent the divided input space and sel ect an appropriate subnetworks, each of which is trained over a different region of input space. The overall architecture of multiple neural networks system, called the federated architecture, consists of a facilitator, normal subnetworks, and tile networks. The role of a facilitator is to choose the subnetwork that is suitable for the given input data using information obtained from decision tree. However, if input data is close enough to the boundaries of regions, there is a large possibility of selecting the invalid subnetwork due to the incorrect prediction of decision tree. When such a situation is encountered, the facilitator selects a tile network that is trained closely to the boundaries of partitioned input space, instead of a normal subnetwork. In this way, it is possible to reduce the large error of neural networks at zones close to borders of regions. The validation of our approach is examined and verified by applying the federated neural networks system to the configuration design of a midship structure.

• 천문학회보
• /
• 제39권1호
• /
• pp.61.2-61.2
• /
• 2014

We present a set of fiducial sequences of horizontal-branch stars in bright Galactic globular clusters, which have previously been observed in the Sloan Digital Sky Survey (SDSS). We derive fiducial lines on color-magnitude diagrams in multiple color indices (g - r, g - i, g - z, and u - g), after rejecting foreground and background objects as well as RR Lyrae variables utilizing these color indices. We compare our fiducial sequences with model predictions from Yonsei-Yale evolutionary tracks and BaSel spectral libraries, and find a satisfactory agreement between them in terms of their color-magnitude relations, except in u - g. We also compare theoretical models to color-magnitude diagrams of two open clusters (M67 and NGC 6791). Based on our best available cluster distance and reddening, we find that the mass of red clump (RC) stars in NGC 6791 is about a factor of two smaller than an earlier estimate from the application of asteroseismic scaling relations for solar-like oscillations. The smaller RC mass implies an enhanced mass loss along the red giant branch, which is in accordance with other compelling evidences found in this metal-rich system. Our estimated luminosity of RC stars in NGC 6791 is about 0.2 mag fainter than in earlier investigations based on solar-metallicity calibrations, and results in ~10% reduction in the RC-based distance estimation, when applied to metal-rich systems such as in the Galactic bulge.

• 대한치과교정학회지
• /
• 제49권1호
• /
• pp.32-40
• /
• 2019

Objective: Precise identification of landmarks on posteroanterior (PA) cephalograms is necessary when evaluating lateral problems such as facial asymmetry. The aim of the present study was to investigate whether the use of lateral (LA) cephalograms can reduce errors in landmark identification on PA cephalograms. Methods: Five examiners identified 16 landmarks (Cg, N, ANS, GT, Me, RO, Lo, FM, Z, Or, Zyg, Cd, NC, Ms, M, and Ag) on 32 PA cephalograms with and without LA cephalograms at the same time. The positions of the landmarks were recorded and saved in the horizontal and vertical direction. The mean errors and standard deviation of landmarks location according to the use of LA cephalograms were compared for each landmark. Results: Relatively small errors were found for ANS, Me, Ms, and Ag, while relatively large errors were found for N, GT, Z, Or, and Cd. No significant difference was found between the horizontal and vertical errors for Z and Or, while large vertical errors were found for N, GT, and Cd. The value of identification error was lower when the landmarks were identified using LA cephalograms. Statistically significant error reductions were found at N and Cd with LA cephalograms, especially in the vertical direction. Conclusions: The use of LA cephalograms during identification of landmarks on PA cephalograms could help reduce identification errors.

• CRM연구
• /
• 제4권1호
• /
• pp.35-54
• /
• 2011

고객기반 온라인 커뮤니티에서 고객들이 생성하는 정보 자원은 기업의 상품 및 서비스를 개발하는 데에 직접적으로 반영되기도 하며 기업과 고객 사이의 직접적인 상호작용을 촉진하기도 한다. 따라서 최근 고객기반 온라인 커뮤니티의 운영과 지속적인 성장에 대한 기업의 관심이 점차 증가하고 있다. 온라인 커뮤니티의 존속과 성장은 커뮤니티 회원들의 자발적인 기여에 의해 이루어진다. 본 연구는 고객기반 온라인 커뮤니티 사용자들의 기여행위 기저에 존재하는 사회 심리학적인 요인들에 대해 초점을 맞추고, 물리적 세계의 실제 자아와 온라인 공간에서 창조되는 가상 자아 사이의 차이가 익명성과 관련된 심리적 반응 요인들(자율권, 회복, 카타르시스)과 기여행위에 어떠한 영향을 미치는지 고찰하였다. 114명의 고객기반 온라인 커뮤니티 사용자로부터 수집된 서베이 자료를 분석한 결과, 실제 자아와 가상 자아의 차이는 개인적 능력을 나타내는 측면과 사회적 능력을 나타내는 부분으로 구별되며, 각각은 지각하는 자율권, 회복에 서로 다른 영향을 미치는 것으로 나타났다. 또한 자율권, 회복, 카타르시스 각각의 요인들도 기여의 질적인 측면과 양적인 측면에 서로 다른 영향을 미치는 것으로 나타났다. 이러한 결과를 기반으로 이론적, 실무적 함의에 대해 토의하였다.