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.

스마트팜 환경 관리를 위한 계측 시스템

이동형(Dong-Hyung Lee),백창대(Chang-Dae Back),윤현성(Hyeon-Seong Yun),손형민(Hyeong-Min Son),차현석(Hyun-Seok Cha),김남호(Nam-Ho Kim) 한국정보통신학회 2021 한국정보통신학회 종합학술대회 논문집 Vol.25 No.2

정보통신기술이 점차 발전함에 따라 기존의 생산 시스템에 네트워크 및 컴퓨팅 기술을 적용하여 효율적인 생산 환경을 유지하는 연구가 많이 진행되고 있다. 고전적인 제어 시스템과 달리 이러한 스마트 생산 시스템은 생산 환경에 대한 데이터를 실시간으로 수집하여 통계화하고, 그 변화에 따라 유동적으로 작동할 필요가 있다. 본 논문에서는 네트워크 기반의 센서를 통해 실시간으로 데이터를 수집하고, 환경 변화에 효과적으로 대응할 수 있는 계측 시스템을 제시한다. 또한 이를 스마트팜에 적용하여 외부의 환경 변화에 대처하고 효과적인 생산 환경을 유지할 수 있음을 확인하였다. As information and communication technologies develop, many studies are being conducted to maintain an efficient production environment by applying network and computing technologies to existing production systems. Unlike classical control systems, these smart production systems need to collect data about the production environment in real time, and operate fluidly as it changes. In this paper, we present a measurement system that can collect data in real time through network-based sensors and respond effectively to environmental changes. We also proved this smart system can cope with external environmental changes and maintain an effective production environment.

ISDN 서비스의 품질개선에 관한 연구

장대석,김영랑 群山大學校 情報通信技術硏究所 1999 情報通信技術硏究論文集 Vol.3 No.-

This paper provides the methods of improving the service quality by analyzing the problems in operating ISDN systems. The main features of the proposed methods are shown as follows; 1) the improvement of ISDN switching systems in the aspects of both hardware and software, by having enough capacity of it, 2) the enhancement of interworking between PC networks and intenrnets of ISDN systems, and 3) the enlargement of the unification of ISDN-PSTN networks, and construction of common channel signal networks

디지탈 이동통신에서의 주파수선택성 페이딩보상에 관한 연구

張大錫 군산대학교 1991 群山水産專門大學 硏究報告 Vol.25 No.2

Because of the effects of the frequency selective fading by the multipath in digital mobile radio communications, it is necessary to establish the anti-fading techniques. In this paper an analysis of the multipath in the digital radio wide band transmission system was investigated, and computer simulation was carried out on the BER in case of the adoption of four elements adaptive arrays. The result shows that CMA adaptive - array method is of fective in the anti-selective frequency fading.

국산 DAF 펌프의 기포특성

안대명,이창한,최윤찬,조석호,안갑환,김성수 대한상하수도학회 2002 상하수도학회지 Vol.16 No.4

The paper introduces a domestic pump designed for dissolved air flotation (DAF). In the paper, the difference in performance between the domestic DAF pump and conventional pressure saturator is explained using the characteristics of air bubble released. The size distribution of air bubbles released from DAF pump is measured by image analyzer and particle size analyzer. And the mean diameter of bubbles is 43μm. The results are similar to that of pressure saturator. The air volume concentration in the water of domestic DAF pump and pressure saturator are 40 and 70% of theoretical amounts. In DAF system used domestic DAF pump, the removal efficiency of turbidity is 70%.

성인 만성 부비동염에서 내시경적 부비동 수술 전·후의 증상 호전도와 음향비강통기도 검사 결과

김용대,김재열,장근영,이형중,송시연,윤석근 영남대학교 의과대학 2002 Yeungnam University Journal of Medicine Vol.19 No.1

Background: Chronic paranasal sinusitis is one of the most common disease in the otorhinolaryngologic field. Endoscopic sinus surgery is treatment of choice in chronic paranasal sinusitis. The aim of this study was to evaluate objective and subjective treatment outcomes of endoscopic sinus surgery in adult chronic paransal sinusitis with or without polyp. Materials and Methods: We reviewed 84 adult patients underwent endoscopic sinus surgery by one surgeon from June 1999 to June 2000, prospectively. We analyzed preoperative and postoperative subjective symptom scores and acoustic rhinometric results. Results: Fifty cases were male and thirty four cases female. The average age was of 33 year-old (range: 17 to 66 years). There was significantly improvement of symptom scores in postoperative 3 months and 6 months compared with preoperative symptom scores. There was significantly increased postoperative total volume of nasal cavity. When we compared high score group with low score group, there was statistically significant improvement of symptom scores between preoperative stage and postoperative 3 months in radiologic grading group. Conclusion: Endoscopic sinus surgery is considered to be effective for the treatment of chronic paranasal sinusitis. It seems to be helpful to employ subjective symptom score system and objective total volume change of nasal cavity through acoustic rhinometric test to analyze effectiveness of endoscopic sinus surgery. In this study, the most important preoperative factor of sinus surgery outcomes is radiologic grading system.

洪水追跡法에 의한 河道變移豫測(Ⅰ) (理論)

李大澈,이종석,朴昌圭 大田産業大學校 1996 한밭대학교 논문집 Vol.13 No.1

This study is in order to evaluate for the topographic variation by the flood routing method in alluvial channel of the erodibility. Basic equations in natural open channel induced from the control volume for the governing equation with continuity and momentum in water and sediment and the solution for these equations worked out by the finite difference method in numerical analysis. Predictions of the topographic variation leading out from as change direction and rate the various in channel width, changes in bed profiles and radius of curvature. And also, bank erodibility factor induced by the correction coefficient with conditions of bank organization and material properties, and the values used in zero to one from non-erodibility bank to non-cohesive bank, respectively.

비부비동 반전성 유두종의 전산화 단층촬영상과 자기공명영상의 분석

배창훈 ( Chang Hoon Bai ),서영중 ( Young Jung Seo ),이석춘 ( Seok Choon Lee ),천승민 ( Seung Min Chen ),백운회 ( Un Hoi Baek ),정은채 ( Eun Chae Jung ),송시연 ( Si Youn Song ),김용대 ( Yong Dae Kim ) 영남대학교 기초/임상의학연구소 2005 Yeungnam University Journal of Medicine Vol.22 No.2

Background: Computed tomography (CT) is commonly used to evaluate the degree of sinus involvement in cases of inverted papilloma (IP). However, CT cannot differentiate tumor from adjacent inflammatory mucosa or retained secretions. By contrast, magnetic resonance imaging (MRI) has been reported to be useful in distinguishing IP from paranasal sinusitis. This study investigated whether preoperative assessment with MRI and CT accurately predict the extent of IP.1) Materials and methods: CT and MRI were retrospectively reviewed in 9 cases of IP. Patients were categorized into stages based on CT and MRI findings, according to the staging system proposed by Krouse. The involvement of IP in each sinus was also assessed. Results: Differentiation of IP from inflammatory disease may be more successful in routine cases where the inflammatory mucosa has low signal intensity on T1-weighted images and very high signal intensity on T2-weighted images. CT imaging could not differentiate tumor from adjacent inflammatory mucosa or retained secretions. Conclusion: Preoperative MRI of IP can predict the location and extent of the tumor involvement in the paranasal sinuses and sometimes predicts malignant changes.

전북지역 이동통신을 위한 수신 전계강도에 관한 연구

문정원,장대석 群山大學校 情報通信技術硏究所 1998 情報通信技術硏究論文集 Vol.2 No.-

In this paper, theoritical calculations using M. Hata Model have been carried out in the wave pass in Chonbuk area, the measurements have been confirmed in the each path, and compared with theoritical results. The analyzed results show that Okku station has the more stable charateristics than Chunju and Kunsan, the values of pass loss are low in the wide road width, in the lots of cross points, in the linear roads, and those of the loss are high in the crowded area which has many buildings and hills.

분자역학적 방법을 이용한 부산시내 대형건물 냉각탑수의 레지오넬라균의 형별 분류

김정만,정석훈,서대영,박은희,송은주,최재철,이은엽,장철훈 대한임상미샐물학회 2004 Annals of clinical microbiology Vol.7 No.1