Wi-Fi 핑거프린트 기반 실내 이동 경로 데이터 생성 방법

윤창표(Chang-Pyo Yoon),황치곤(Chi-Gon Hwang) 한국정보통신학회 2021 한국정보통신학회 종합학술대회 논문집 Vol.25 No.1

최근, 실내 위치 기반 서비스에서 정확한 서비스를 위해 Wi-Fi 핑거프린트 기반의 딥러닝 기술을 이용한 연구가 이루어지고 있다. 딥러닝 모델 중에서 과거의 정보를 기억할 수 있는 RNN 모델은 실내측위에서 연속된 움직임을 기억할 수 있어 측위 오차를 줄일 수 있다. 이때 학습 데이터로서 연속적인 순차 데이터를 필요로 한다. 그러나 일반적으로 Wi-Fi 핑거프린트 데이터의 경우 특정 위치에 대한 신호들만으로 관리되기 때문에 RNN 모델의 학습데이터로 사용이 부적절하다. 본 논문은 RNN 모델의 순차적인 입력 데이터의 생성을 위해 클러스터링을 통한 영역 데이터로 확장된 Wi-Fi 핑거프린트 데이터 기반 이동 경로의 예측을 통한 경로 생성 방법에 대해 제안한다. Recently, researches using deep learning technology based on Wi-Fi fingerprints have been conducted for accurate services in indoor location-based services. Among the deep learning models, an RNN model that can store information from the past can store continuous movements in indoor positioning, thereby reducing positioning errors. At this time, continuous sequential data is required as training data. However, since Wi-Fi fingerprint data is generally managed only with signals for a specific location, it is inappropriate to use it as training data for an RNN model. This paper proposes a path generation method through prediction of a moving path based on Wi-Fi fingerprint data extended to region data through clustering to generate sequential input data of the RNN model.

스플라인 알고리즘을 이용한 비드 가시화

구창대(Chang-Dae Koo),양형석(Hyeong-Seok Yang),김맹남(Maeng-Nam Kim) 대한용접·접합학회 2016 대한용접·접합학회지 Vol.34 No.1

In this research paper, suggest method of generate same bead as an actual measurement data in virtual welding conditions, exploit morphology information of the bead that acquired through robot welding. It has many multiple risk factors to Beginners welding training, by we make possible to train welding in virtual reality, we can reduce welding training risk and welding material to exploit bead visualization algorithm that we suggest so it will be expected to achieve educational, environmental and economical effect. The proposed method is acquire data to each case performing robot welding by set the voltage, current, working angle, process angle, speed and arc length of welding condition value. As Welding condition value is most important thing in decide bead form, we would selected one of baseline each item and then acquired metal followed another factors change. Welding type is FCAW, SMAW and TIG. When welding trainee perform the training, it’s difficult to save all of changed information into database likewise working angle, process angle, speed and arc length. So not saving data into database are applying the method to infer the form of bead using a neural network algorithm. The way of bead’s visualization is applying the spline algorithm. To accurately represent Morphological information of the bead, requires much of morphological information, so it can occur problem to save into database that is why we using the spline algorithm. By applying the spline algorithm, it can make simplified data and generate accurate bead shape. Through the research paper, the shape of bead generated by the virtual reality was able to improve the accuracy when compared using the form of bead generated by the robot welding to using the morphological information of the bead generated through the robot welding. By express the accurate shape of bead and so can reduce the difference of the actual welding training and virtual welding, it was confirmed that it can be performed safety and high effective virtual welding education.

Gene Expression Analysis of the Bromobenzene Treated Liver with Non-hepatotoxic Doses in Mice

Lim, Jung-Sun,Jeong, Sun-Young,Hwang, Ji-Yoon,Park, Han-Jin,Cho, Jae-Woo,Song, Chang-Woo,Kim, Yang-Seok,Lee, Wan-Seon,Moon, Jin-Hee,Han, Sang-Seop,Yoon, Seok-Joo The Korean Society of Toxicogenomics and Toxicopro 2005 Molecular & cellular toxicology Vol.1 No.4

Bromobenzene (BB) is well known hepatotoxicant. Also, BB is an industrial solvent that arouses toxicity predominantly in the liver where it causes centrilobular necrosis. BB is subjected to Cytochrome P450 mediated epoxidation followed by either conjugation with glutathione, enzymatic hydrolysis or further oxidation. In this study, we focused on BB-induced gene expression at non-hepatotoxic dose. Mice were exposed to two levels of BB, sampled at 24 h, and hepatic gene expression levels were determined to evaluate dose dependent changes. When examining the toxic dose of BB treated group in other previous studies, genes related to heat shock protein, oxidative stress, and drug metabolism are expressed. Compared to these results, our study, in which non-toxic dose of BB was administrated, showed similar patterns as the toxic conditions above. The purpose of the study was to select genes that showed changes in relation to the differing dose through confirmation of the difference within transcriptomic boundaries, but those that are not detected by the existing classic toxicology tools in non-hepatotoxic dose.

고압 커패시터의 고장 분석을 통한 신뢰도 예측

양석준,김진우,신승우,이희진,신승훈,유동수,장석원 한국비파괴검사학회 2001 한국비파괴검사학회지 Vol.21 No.6

본 논문은 고압 커패시터의 고장분석과 신뢰성 예측 결과를 다루고 있다. 부품의 수명과 고장률을 예측하기 위해서 두 가지 방법으로 고장 모드와 고장 메커니즘을 연구하였다. 에폭시 수지로 성형된 고압 커패시터가 절연내압 시험 하에서 저항이 제로로 되는 고장에 대하여, 근본원인 고장분석 체계를 효과적으로 수립함으로써 고장 메커니즘의 원인을 분석하였다. 특히 세라믹-에폭시 계면에서의 절연파괴 고장 현상이 강조되었으며, 본 연구에서 얻어진 결과의 타당성은 마그네트론에 장착된 고압 커패시터의 열사이클 시험 수행에 의한 가속시험 결과로부터 입증되었다. 시험 결과들은 결함이 있는 로트를 신속히 규명하고 B10수명을 결정하는데 유용하게 사용할 수 있다. 또한, 유전체의 절연파괴에 대해서 부하-강도 간섭모델을 이용하여 고장률을 예측하였다. This paper presents a result of failure analysis and reliability evaluation for high voltage ceramic capacitors. The failure modes and failure mechanisms were studied in two ways in order to estimate component life and failure rate. The causes of failure mechanisms for zero resistance phenomena under withstanding voltage test in high voltage ceramic capacitors molded by epoxy resin were studied y establishing an effective root cause failure analysis. Particular emphasis was placed on breakdown phenomena at the ceramic-epoxy interface. The validity of the results in this study was confirmed by the results of accelerated testing. Thermal cycling test for high voltage ceramic capacitor mounted on a magnetron were implemented. Delamination between ceramic and epoxy, which might cause electrical short in underlying circuitry, can occur during curing or thermal cycle. The results can be conveniently used to quickly identify defective lots, determine B10 life estimation each lot at the level of inspection, and detect major changes in the vendors processes. Also, thd condition for dielectric breakdown was investigated for the estimation of failure rate with load-strength interference model.

HBsAg 양성 환자의 혈청에서 branched DNA 신호 증폭 방법을 이용한 B형 간염바이러스 DNA의 정량

기창석,양윤선,김종원 대한임상병리학회 1997 대한임상병리학회지 Vol.17 No.5

노즐형상비에 따른 디젤분무의 특성

양윤석,이창수,허종철 濟州大學校 産業技術硏究所 2001 산업기술연구소논문집 Vol.12 No.1

In this study. diesel spray characteristics has been conducted to investigate the effect on nozzle aspect ratio(L/D). A single hole nozzle which is 0.45mm in diameter and 2.78. 3.89. 5 in the nozzle aspect ratio is used. Injection pressure is 14MPa and ambient pressure are 0.1MPa and 3MPa. By nozzle aspect ratio. the disintegration process of a diesel spray was observed. The double flash method has been employed to visualize the developing process of the diesel spray.

조기 양막 파수 신생아에 대한 임상적 연구

양은석,김강호,박상기,나창수 朝鮮大學校 附設 醫學硏究所 1989 The Medical Journal of Chosun University Vol.14 No.1

A clinical study was made on 157 newborns of mothers with premature rupture of membranes (study group) and 916 newborns of mothers without rupture of membranes (control group) at Chosun University Hospital from Jaunary 1987 to Decembcr 1988. The results were as follows: 1) The incidence of PROM was 14.6%. 2) 10.2% of all babies with PROM were born prematurely, significantly higher than the incidence of PROM in all newborn cases with 4.8% (P<0.005). 3) The incidence of neonatal sepsis in the PROM group (4.5%) was four times higher than in the normal group(1.1%) (P<0.005). The incidience was related to the gestational age at birth, and also increased with increasing time interval after PROM. 4) The incidence of neonatal asphyxia in PROM group (7.6%) was twice the normal group (3.6%) (P<0.025). The premature babies had greater incidence in both groups. Also, a positive correlation was found with increasing time interval PROM. 5) Neonatal respiratory distress syndrome(RDS) was found in 1.3% of babies with PROM, whereas 1.4% of babies in the normal group had the syndrome. Premature babies had higher incidence of RDS in both normal and PROM groups, but the latter had an incidence amounting the only 1/5 of the former. And it tended to diminish with creasing time interval after PROM.

CAD/CAM을 이용한 맞춤형 임플란트 지대주의 나사 풀림 토크 평가

이창재,양성은,김석규 대한치과보철학회 2012 대한치과보철학회지 Vol.50 No.2

연구 목적: 본 연구는 국내 개발된 맞춤형 임플란트 지대주와 기성 임플란트 지대주의 반복 하중 전과 후의 나사 풀림 토크 값을 측정, 비교하여 나사 결합부 안전성에 차이가 있는지를 알아보고자 하였다. 연구 재료 및 방법: 총 12개의 임플란트 고정체(Implantium, Dentium Co., Seoul, Korea)를 알루미늄 원통에 레진으로 고정하고, 그것을 각각 4개씩, 3개의 군으로 나눠서 각 군별로 기성 티타늄 지대주(Implantium, Dentium Co., Seoul, Korea), 캐드캠 맞춤형 티타늄 지대주(Myplant, Raphabio Co., Seoul, Korea), 그리고 금속 연결부가 있는 캐드캠 맞춤형 지르코니아 지대주(Zirconia Myplant, Raphabio Co., Seoul, Korea)를 제작하여 임플란트에 연결하였다. 금속관은 지대주에 맞춰서 티타늄을 밀링해서 제작한뒤 지대주에 합착하였다. 반복 하중을 가하기 전에 지대주 나사를 30 Ncm 토크로 조이고 약 30분 후 나사의 초기 풀림 토크값을 측정하였다. 그 후 반복 하중을 30 N에서 120 N의 싸인 곡선을 이루는 압축력으로 2 Hz의 빈도로 50만 싸이클을 가하고 하중 후 풀림 토크값을 측정하였으며, 풀림 토크 상실률을 구하여서 군끼리 비교하였다. 나사의 풀림 토크값의 상실률의 비교를 위해 Kruskal-Wallis test를 이용해서 유의수준 .05에서 분석하였다. 결과: 반복하중 후 나사 풀림 상실률에서 기성 티타늄 지대주 군에 비해 맞춤형 티타늄 지대주는 높은 값을 보였으나 유의성 있는 차이를 보이지 않았다(P>.05). 반면, 맞춤형 지르코니아 지대주는 기성 티타늄 지대주에 비해 유의하게 높은 값을 보였다(P=.014). 결론: 본 실험의 한계 내에서 캐드캠 맞춤형 티타늄 임플란트 지대주는 기성 임플란트 지대주에 비해 나사 안정성이 떨어진다고 볼 수 없다. 반면, 캐드캠 맞춤형 지르코니아 지대주 는 기성 임플란트 지대주에 비해 나사 안정성이 다소 떨어진다고 볼 수 있다. Purpose: The purpose of this study was to compare the screw joint stability between the CADCAM custom-made implant abutment and the prefabricated implant abutment by measuring the reverse torque value after cyclic loading. Materials and methods: Twelve screw type implants (Implantium, Dentium Co., Seoul, Korea) were embedded in aluminum cylinder with acrylic resin. The implant specimens were equally divided into 3 groups, and connected to the prefabricated titanium abutments (Implantium, Dentium Co., Seoul, Korea), CADCAM custom-made titanium abutments (Myplant, Raphabio Co., Seoul, Korea) and CADCAM custom-made zirconia abutments (Zirconia Myplant, Raphabio Co., Seoul, Korea). The CAD-CAM milled titanium crown (Raphabio Co., Seoul, Korea) was cemented on each implant abutment by resin cement. Before cyclic loading, each abutment screw was tightened to 30 Ncm and the reverse torque value was measured about 30 minutes later. After the crown specimen was subjected to the sinusoidal cyclic loading (30 to 120 N, 500,000 cycles, 2 Hz), postloading reverse torque value was measured and the reverse torque loss ratio was calculated. Kruskal-Wallis test was used for statistical analysis of the reverse torque loss ratio. Results: The CADCAM custom-made titanium abutments presented higher values in reverse torque loss ratio without statistically significant differences than the prefabricated titanium abutments (P>.05). Reverse torque loss ratio of the custom-made zirconia abutments was significantly higher compared to that of the prefabricated titanium abutments (P=.014). Conclusion: Within the limitation of the present in-vitro study, it was concluded that there was no significant difference in screw joint stability between the CADCAM custom-made titanium abutments and the prefabricated titanium abutments. On the other hand, the CADCAM custom-made zirconia abutments showed lower screw joint stability than prefabricated titanium abutments.

비장의 상피양 낭종 : 1예 보고 A Report of A Case

양기화,강창석,심상인,김선무,함흥정 최신의학사 1986 最新醫學 Vol.29 No.12

여성 외음부에 발생한 선상 편평상피세포암종

김창옥,양기화,강석진,이안희,김병기,김선무 대한병리학회 1991 Journal of Pathology and Translational Medicine Vol.25 No.1