홈 트레이닝을 위한 운동 동작 분류 및 교정 시스템

강재민,박성수,김윤수,감진규,Kang, Jae Min,Park, Seongsu,Kim, Yun Soo,Gahm, Jin Kyu 한국정보통신학회 2021 한국정보통신학회논문지 Vol.25 No.9

홈 트레이닝을 하는 사람들은 전문적인 대면 지도가 없기 때문에 잘못된 자세로 동작을 하여 신체에 무리가 올 수 있다. 본 연구에서는 자세 예측 모델과 다층 퍼셉트론을 이용하여 사용자의 자세를 교정 해주는 "영상 데이터 기반 동작 분류 및 자세 교정 시스템"을 제안한다. 자세 예측 모델로 뼈대 정보를 예측한 후 심층 신경망을 이용하여 어떤 운동 동작인지를 분류한 뒤, 올바른 관절의 각도를 알려주며 교정이 이루어진다. 이 과정에서 동작 분류 모델의 성능을 향상시키기 위해 연속적인 프레임들의 결과를 고려하는 투표 알고리즘을 적용하였다. 다층 퍼셉트론 기반 모델을 자세 분류 모델로 사용했을 때 0.9의 정확도를 가진다. 그리고 투표 알고리즘을 통해 분류 모델의 정확도는 0.93으로 향상된다. There have been recently an increasing number of people working out at home. However, many of them do not have face-to-face guidance from experts, so they cannot effectively correct their wrong pose. This may lead to strain and injury to those doing home training. To tackle this problem, this paper proposes a video data-based pose classification and correction system for home training. The proposed system classifies poses using the multi-layer perceptron and pose estimation model, and corrects poses based on joint angels estimated. A voting algorithm that considers the results of successive frames is applied to improve the performance of the pose classification model. Multi-layer perceptron model for post classification shows the highest accuracy with 0.9. In addition, it is shown that the proposed voting algorithm improves the accuracy to 0.93.

GPS기반 항공 항법 장비를 위한 전파위협원 위치추적 시작품 개발

강재민,임덕원,천세범,허문범,염찬홍,Kang, Jae Min,Lim, Deok Won,Chun, Sebum,Heo, Moon Beom,Yeom, Chan Hong 항공우주시스템공학회 2014 항공우주시스템공학회지 Vol.8 No.2

In this paper, a prototype of GPS jammer localization system for precise landing is developed. The jammer localization system consists of the four jamming signal receivers for collecting RF signal, one central tracking station for estimating jammer position, and one monitoring station for displaying estimated position on the map. In order to estimate jammer location TDOA and AOA algorithm are introduced, and the function and design parameters of the developed prototype are proposed. CW, DSSS, Swept CW jamming signals were generated and used. From the results, it can be confirmed that developed system meets the performance goal.

치면열구전색재와 충전재료에 대한 우식유발 세균의 부착특성 비교

강재민(Jae-Min Kang),임상욱(Sang-Uk Im),조화영(Jae-Min Kang),마재경(Jae-Kyung Ma),김정숙(Jeong-Sook Kim),김교한(Kyo-Han Kim),송근배(Keun-Bae Song),최연희(Youn-Hee Choi) 대한치과재료학회 2015 대한치과재료학회지 Vol.42 No.3

Streptococcus mutans (S. mutans) is most commonly founded Mutans Streptococci group in human oral cavity. This study aimed to compare the adhesion ability of Xylitol-sensitive (Xs) and Xylitol-resistant (Xr) on three filling materials which are currently used by dentists. Hydroxyapatite (HA) disk (control group, n=36), sealant (n=36), resin (n=36), glass-ionomer (n=36) disks were made by mold (10.2 mm Ø, 3 mm hight). Xs and Xr of S. mutans KCTC3065 and S. mutans UA159 were formed and cultured in TYE media. After culture, 500 ㎕ of 0.01% crystal violet was added to the plate, dyeing was performing, and mixed 1 ㎖ solution of ethanol:acetone (4:1 w/w) for reaction termination. The absorbance of the extracted solution was measured by using ELISA reader and the extracted solution on disk was observed with SEM. The adhesion ability was calculated by ELISA reader. Adhesion ability of Xs and Xr from S. mutans of resin was higher than those of HA disk and the adhesion ability of sealant was lower compared to those of HA disk. Sealant had the lowest adhesion ability of dental caries-inducing bacteria among three filling materials when viewed in terms of relevance of the material and decay-inducing bacteria in oral cavity.

회계정보의 제공순서와 응답방식이 감사인의 의사결정에 미치는 영향

강재민 ( Jae Min Kang ) 한국세무회계학회 2009 세무회계연구 Vol.24 No.-

다종 전파교란원 위치추정을 위한 식별 및 측정치 획득 알고리즘 설계

강재민 ( Jae Min Kang ),임덕원 ( Deok Won Lim ),허문범 ( Moon Beom Heo ),남기욱 ( Gi Wook Nam ) 한국항행학회 2013 韓國航行學會論文誌 Vol.17 No.6

전파 교란신호가 발생할 경우, GPS 기반의 정밀위치제공시스템에 오작동을 일으킬 수 있으며 특히, 항공분야에서는 더 심각한 피해가 발생할 수 있다. 하나의 전파교란원에 대한 대응 기법이나 위치 추정 기법의 연구 결과는 잘 알려져 있으나, 다수의 전파교란원이 다양한 형태의 신호를 송출할 경우에는 대응 및 위치 추정이 어렵다. 따라서 본 논문에서는 다수의 전파위협원이 CW, DSSS, SCW 형태의 신호를 송출할 경우에 위치 추정을 수행할 수 있도록 하기 위하여 신호 식별 및 측정치 획득 방법을 제안한다. 또한 제안한 방법을 검증하기 위하여 MATLAB을 이용하여 모의실험을 수행하였다. 실험 결과로부터 제안한 방법은 CW, DSSS, SCW 형태의 교란신호를 정상적으로 식별하고 측정치를 정확하게 획득하는 것을 검증하였다. When jamming signal is received, there would be malfunctions in GPS-based precise location systems. Especially, in aviation fields, these malfunctions may lead to more serious damages. Naturally, there are some research results about the prevention or location method for one jammer, but it is hard to identify and obtain measurements when multiple and various type signals are received. Therefore, we propose a method of identification and measurements acquisition algorithm in order to localize the multiple jammers which transmit CW, DSSS and SCW type signals. Also, a computer simulation is carried out so as to validate the feasibility of the proposed method by using MATLAB. From the simulation results, it is confirmed that the proposed method successfully identified the signal type and acquired the measurements of CW, DSSS and SCW type signals.

냉연강판에서의 표면결함 분류를 위한 생성적 적대 신경망 기반 데이터 증강

강재민(Jae Min. Kang),최원준(Won June Choi),감진규(Jin Kyu Gahm) 한국멀티미디어학회 2024 멀티미디어학회논문지 Vol.27 No.2

With the recent increase in demand for steel products, the need for high-quality steel has intensified. Cold-rolled steel strip often exhibit various surface defects due to numerous roll pressing processes. Some of these surface defects can lead to critical issues in steel product manufacturing. Thus, developing a high-performance model for classifying steel sheet defects is crucial for producing and maintaining high-quality metal products. In this paper, we propose a data augmentation model using Generative Adversarial Networks (GANs) to generate images of defects for classes with insufficient data. Additionally, we introduce a pre-processing method designed to minimize the loss of defect information when resizing images. Our experimental results demonstrate that applying the proposed method significantly improves performance, evidenced by an increase of up to 6% in the classification F1-score.

제주노선 항공여객의 항공사 선택속성에 대한 탐색적 연구

강재민 ( Jae-min Kang ),박용화 ( Yong-hwa Park ),임철현 ( Cheol-hyun Lim ) 한국항공경영학회 2017 한국항공경영학회지 Vol.15 No.5

In this study, we analyzed characteristics of Jeju air passengers and did the analysis of characteristics, economic and social conditions of Jeju air routes. In order to achieve the purpose of this study, we conducted surveys on passengers over 20 years of age, except airline employees, on Jeju air routes. Specifically, the surveys were based on departing flights from Jeju airport(CJU) to other domestic airports through domestic and international airlines. The surveys had been conducted for the different dates to consider seasonality. Statistical analysis of the collected data had been performed with frequency analysis and one-way ANOVA using IBM SPSS Statistics 21. According to the survey results, flight safety, ticket price, cabin crew kindness, on-time departure and arrival, and reservation convenience ranked higher than the other factors of consumer preferences. However, according to the characteristics of the passengers, it has been found that there are differences in airfare, competent reservation system, reservation convenience, speedy reservation confirm, and accuracy of information. As a result, airlines must make all-out efforts to provide ‘safe flight’ and ‘low airfare’ to passengers. It is also analyzed that it is necessary to make a lot of efforts into improving on-time aircraft operations and enhancing the reservation related services. It is important to note that there is a significant difference in the importance of airline selection attributes by age, and it will be necessary to identify the age of the major passengers and provide tailored customer service to those attributes.

우리나라 권역 장애인구강진료센터 이용자 만족요인 비교

정윤숙,최영애,강재민,이영은,송근배,Jung, Yun-Sook,Choi, Yeong-Ae,Kang, Jae-Min,Lee, Young-Eun,Song, Keun-Bae 한국치위생학회 2021 한국치위생학회지 Vol.21 No.2

Objectives: The purpose of this study was to identify the factors of satisfaction with regional oral health centers for people with disabilities in Korea. Methods: A survey was conducted with 784 patients who visited regional oral health care centers in Korea. A self-developed questionnaire (29 items) was adapted with a consent form and IRB (Institutional Review Board). All collected data were analyzed for statistics using SPSS version 25.0. Results: The study participants were 452 (57.7%) male patients, 207 (26.4%) aged 20-29 years old, and mostly had physical, developmental, and mental disabilities. The patients were introduced by their acquaintances, and the major reason for visit was specific dental care for the disabled. Most patients used their cars and took half to one hour to commute. The common factor affecting the comprehensive satisfaction was the facility satisfaction. Conclusions: A more comprehensive and standardized questionnaire should be developed for the annual evaluation of all centers. This study presents the basic data that can aid to activate the operation of the four oral health care centers for the disabled, which are scheduled to be implemented in the future, as well as 10 currently operated centers.

GPS 전파교란원 위치 추정을 위한 TDOA/AOA 복합 기법 설계

임덕원(Deok Won Lim),강재민(Jae Min Kang),허문범(Moon Beom Heo) 제어로봇시스템학회 2014 제어·로봇·시스템학회 논문지 Vol.20 No.1

For a localization system, the TDOA (Time Difference of Arrival) measurement and AOA (Angle of Arrival) measurement are often used for estimating target’s positions. Although it is known that the accuracy of TDOA based localization is superior to that of AOA based one, it may have a poor vertical accuracy in bad geometrical conditions. This paper, therefore, proposes a localization algorithm in which the vertical position is estimated by AOA measurements and the horizontal one is estimated by TDOA measurement in order to achieve high 3D-location accuracy. And this algorithm is applied to a GPS jammer localization systems because it has a large value of the DOP (Dilution of Precision) when the jammer is located far away from the system. Simulation results demonstrate that the proposed hybrid TDOA/AOA location algorithm gives much higher location accuracy than TDOA or AOA only location.

위치 기반 서비스를 위한 모바일 단말기 측위 기술 동향

임순(Lim, Soon),강재민(Kang, Jae Min),허문범(Heo, Moon Beom) 한국항공우주연구원 2014 항공우주산업기술동향 Vol.12 No.1

2010년 이후 GPS 모듈이 탑재된 스마트폰의 보급과 함께 위치 기반 서비스가 전 세계적으로 급성장하였으며 스마트폰을 통해서 위치 및 길 안내, 위치 정보와 같은 서비스를 제공받을 수 있게 되었다. 스마트폰에 장착된 소형 GPS 모듈은 기존의 모바일 네트워크를 이용한 측위 방식에 비해 사용자에게 정확도가 높은 측위 정보를 제공하며 Wi-Fi, 블루투스와 같은 모듈은 GPS를 활용할 수 없는 실내 환경에서도 측위가 가능하게 함으로써 사용자의 공간에 제약이 없이 위치 정보를 제공하는 것이 가능해졌다. 본 논문에서는 스마트폰과 같은 모바일 단말기를 이용한 위치 기반 서비스에 대하여 살펴보고 위치 측위 시 활용되는 모바일 단말기 측위 기술에 대하여 소개한다. 그리고 국내외에서 어떠한 측위 기술들이 활용되는지 그 동향에 대하여 소개한다. After 2010, a smart phone with a small and cheap GPS module, a location based service market increased rapidly and smart phone users can provide services such as a navigation, a location information and a rescue service. A GPS module that embedded on a smart phone can provide more enhanced performance of positioning then a based-on a mobile network. Also most smart phones have Wi-Fi and Bluetooth module and these modules can provide a positioning result at an indoor or a basement where GPS signal can not be tracked. In this paper, an outline of location based service provided from mobile devices is presented and positioning techniques of mobile device that are presented. Also the technique trend of mobile device positioning is introduced.