[Project Report]아크로빗타 신축 공사

정태헌(Taehun Chung) 대한건축학회 2005 建築 Vol.48 No.12

나노복합 하이드로겔 액추에이터의 연구동향

정태훈 ( Taehun Chung ),한임경 ( Im Kyung Han ),김연수 ( Youn Soo Kim ) 한국공업화학회 2020 공업화학전망 Vol.23 No.2

소프트 로봇의 수요와 관심이 증가함에 따라 생체 모방형 액추에이터 연구가 큰 관심을 받고 있다. 액추에이터란 외부 에너지를 기계적인 동작으로 변환하는 장치이며, 재료 자체가 유연하여 부드러운 움직임을 재현할 수 있는 소프트 액추에이터의 연구가 활발히 진행되고 있다. 고분자 연성 재료 중에 하나인 하이드로겔은 90% 이상이 물로 구성되어 있기 때문에 생체 친화적이면서 동시에 환경 친화적인 재료이며 이를 기반으로 한 액추에이터 연구가 새로이 각광받고 있다. 최근에는 하이드로겔 액추에이터의 성능 향상을 위해 나노재료를 하이드로겔에 첨가하는 연구가 진행되고 있으며, 나노재료가 갖는 고유의 특성을 활용함으로써 하이드로겔 액추에이터의 자극 감응성 향상, 변형 방향의 제어, 높은 변형 효율 그리고 기계적 물성 증가가 보고되고 있다. 이는 헬스케어를 위한 웨어러블 장치, 재활을 목적으로 한 인공 근육 등에 적용이 가능하다. 본 기고문에서는 자극 감응성 고분자와 나노재료를 이용한 하이드로겔 액추에이터 연구에 대해 자극(전기장, 빛, 열, 자기장)의 종류에 따라 분류하여 소개하고, 합성 전략 및 구동 원리에 대해 간략하게 설명하고자 한다.

Real-time and Precise Indoor Localization System in Multi-Floor Buildings for Pedestrian using Cloud Platform

Taehun Kim,Beomju Shin,Chung G. Kang,Jung Ho Lee,Changsoo Yu,Hankyeol Kyung,Donghyun Shin,Taikjin Lee 제어로봇시스템학회 2022 제어로봇시스템학회 국제학술대회 논문집 Vol.2022 No.11

Pedestrians use their smartphones to determine their location. Accordingly, there is a growing demand for seamless localization that can estimate the location regardless of indoor and outdoor space. However, the Global Navigation Satellite System used for outdoor location estimation has poor reception in the indoor environment, making it difficult to use in indoor space. Therefore, we propose the indoor localization technology based on Surface Correlation (SC). This indoor localization technology can estimate the location of pedestrians on only one floor. In this study, floor detection was performed using only RF signal without using other sensors such as barometric pressure sensor in the multi-floor building. The most important thing in floor detection is the reliability of the current floor and floor change detection. We can estimate the coarse floor using the unique ID of the RF source installed on each floor. Then, the virtual trajectory is generated using only RF signal, and the degree of similarity with the floor is determined by identifying the fine floor of the coarse floor estimated by applying the existing SC-based localization. Once the fine floor of pedestrians is identified, the final absolute location of pedestrians in the multi-floor building can be estimated by calculating the indoor location of the estimated floor using conventional SC-based localization. To verify the performance of the proposed algorithm in real-time, the algorithm was implemented in Google Cloud Platform. Pedestrians can check the indoor location results through real-time connection with the smartphone. In the actual multi-floor building, the similarity between the floor estimated by the proposed algorithm and the floor estimated using the barometric pressure sensor is about 95.0%. And the RMSE of the indoor localization results of the proposed system is about 3.662m.

판재의 초음파 비선형 특성평가를 위한 Lamb Wave 기법

이태훈(Taehun Lee),김정석(Chung Seok Kim),장경영(Kyung-Young Jhang) 한국비파괴검사학회 2010 한국비파괴검사학회지 Vol.30 No.5

음향 비선형성은 재료 물성의 미세한 변화에 민감하기 때문에, 이를 측정하는 비선형 초음파 기술은 재료의 열화나 피로를 평가할 수 있는 기법으로 연구되어 왔다. 하지만 벌크파를 이용하는 일반적인 비선형 초음파 기법은 얇은 판재에 적용하는 것에는 여러 한계가 있다. 이와 같은 경우에는 비선형 Lamb 파의 사용을 생각할 수 있지만, Lamb 파는 벌크파와 매우 다른 전파 특성을 가지고 있어 그 비선형 특성에 대한 별도의 연구를 필요로 한다. 이를 위해 본 연구에서는 Lamb 파에서 비선형성에 의해 전파하면서 누적 성장할 수 있는 2차 고조파 모드의 발생 조건을 분석하였으며, 그 결과 네 가지 조건, 즉 (1) phase matching, (2) non-zero power flux, (3) group velocity matching, (4) non-zero out-of-plane displacement 를 제시하였다. 그리고 제시된 조건으로 알루미늄 판재에 대책 실험한 결과 이론 예측과 동일하게 전파 거리에 따라 2차 고조파 성분의 크기와 비선형 파라미터가 증가하였고, Al6061-T6 과 Al1100-H14에서 측정된 상대적인 비선형 파라미터의 비율이 이론적인 비율과 근접함을 보였다. Since the acoustic nonlinearity is sensitive to the minute variation of material properties, the nonlinear ultrasonic technique(NUT) has been considered as a promising method to evaluate the material degradation or fatigue. However, there are certain limitations to apply the conventional NUT using the bulk wave to thin plates. In case of plates, the use of Lamb wave can be considered, however, the propagation characteristics of Lamb wave are completely different with the bulk wave, and thus the separate study for the nonlinearity of Lamb wave is required. For this work, this paper analyzed first the conditions of mode pair suitable for the practical application as well as for the cumulative propagation of quadratic harmonic frequency and summarized the result in for conditions; (1) phase matching, (2) non-zero power flux, (3) group velocity matching, and (4) non-zero out-of-plane displacement. Experimental results in aluminum plates showed that the amplitude of the secondary Lamb wave and nonlinear parameter growed up with increasing propagation distance at the mode pair satisfying the above all conditions and that the ration of nonlinear parameters measured in Al6061-T6 and Al1100-H15 was closed to the ratio of the absolute nonlinear parameters.

타이어 힘 기반 차량 동역학 제어기 개발

황태훈(Taehun Hwang),정태영(Taeyoung Chung),이규훈(Kyu Hoon Lee),유은영(Eun Young You),여태정(Tae-Jung Yeo) 한국자동차공학회 2010 한국자동차공학회 학술대회 및 전시회 Vol.2010 No.11

Due to the vehicle electronic and development of communication technologies, Besides the basic functions supporting the weight to the vehicle and mitigating the road impact, Tire is adding the additional function such as the TPMS(Tire Pressure Monitoring System). In addition, recently research of the intelligent tire system capable of measuring the tire force have been actively. Yet only the leading technology in the development stage, however, launching of the prototype is expected in the near future according to leading companies and excellent domestic and international research institutions . In this paper, Vehicle dynamic controller is designed using tire force information that occurred between the tire and road surface. The proposed controller is verified using CarSim simulation.

한국과 중국의 형사사법과 교정처우에 관한 비교연구

정진수(CHUNG JINSOO),하태훈(HA TAEHUN),최군용(CHOI KUNYOUNG),김광호(KIM KWANGHO) 한국형사법무정책연구원 2014 형사정책연구원 연구총서 Vol.- No.-

소아 주관절 주위 골절

김태훈 ( Taehun Kim ),조재호 ( Jaeho Cho ),정승민 ( Seungmin Chung ) 대한골절학회 2021 대한골절학회지 Vol.34 No.1

소아 주관절 주변 골절에 대한 최신 지견 및 진단 치료에 대한 연구이다. 최신 소아정형외과 교과서 및 발간된 논문을 참조하여 주관절부 골절에 대한 내용을 정리하였다. 소아 상완골 과상부 골절, 외과 골절, 근위 요-척골 골절에 대하여 각 골절의 진단과 치료에 대한 최신 지견을 축약하였다. 소아주관절부 골절은 다른 동반 손상 및 골절에 대한 정밀한 검사와 치료를 요한다. 소아 환자들은 성장 잠재력이 있어 정확한 치료를 요한다. This study assessed the current concepts of pediatric elbow fractures. PubMed and Embase databases were searched for publications in English on elbow fractures. Papers believed to yield significant findings to this area were included in this review. The supracondyle of humerus, lateral condyle of the humerus, proximal radius, and proximal ulna fractures were included. Sixteen papers and textbooks were selected. Pediatric elbow fractures should be evaluated for combined injuries. Treatment should be done accurately for each fracture for the further growth of children.

실시간 타이어 힘 계측을 통한 샤시 제어 로직 개발

황태훈(Taehun Hwang),이형명(Hyungmyung Lee),유은영(Eunyoung You),정태영(Taeyoung Chung),신광근(Kwangkeun Joseph Shin) 한국자동차공학회 2012 한국자동차공학회 부문종합 학술대회 Vol.2012 No.5

Various types of intelligent tire sensors, which measures tire forces directly, are developed by tire manufacturers and their consortiums for chassis control system application. If a tire sensor can offers forces between tire contact patch and road surface, chassis control systems can be improved with respect to vehicle dynamics aspects. In conventional chassis system, most of vehicle dynamics related variables and parameters are estimated by using chassis sensors, like wheel speed, yaw rate, lateral acceleration and etc. In this paper, we studied a feasibility of wheel force measurements based chassis control logic by using real-time tire force measurements.

Design and optimization of rotating triboelectric nanogenerator by water electrification and inertia

Kim, Taehun,Chung, Jihoon,Kim, Dae Yun,Moon, Joo Hyun,Lee, Sukyung,Cho, Minhaeng,Lee, Seong Hyuk,Lee, Sangmin unknown 2016 Nano energy Vol.27 No.-

<P><B>Abstract</B></P> <P>The recent energy crisis has resulted in numerous energy-harvesting methods receiving significant attention in the past decades. To overcome this crisis, we successfully develop a first-ever rotating water triboelectric nanogenerator (TENG) based on water-electrification and rotating fluid inertia. The proposed TENG is a fully packaged design composed of partially filled cylinder and gear systems. To the best of our knowledge, the correlation of inner fluid motion and electrical voltage output performance using fluid dynamics analysis is demonstrated for the first time. In addition, we propose guidelines for optimum design and operation of a TENG using a non-dimensional factor <I>G</I>, which is based on the angular velocity of the cylinder and the volume ratio of the water and cylinder. In addition, a multiphase fluid flow simulation is introduced to demonstrate fluid dynamic motion and the electrical potential based on instantaneous water motion. Furthermore, a portable hand-driven device combined with a gear train that can light 30 LEDs instantaneously is introduced to demonstrate the wide applicability of the proposed TENG. Thus, our study supports a simple model where a rotating cylinder is filled with water and can be used effectively to expand new types of energy-harvesting methods.</P> <P><B>Highlights</B></P> <P> <UL> <LI> New triboelectric nanogenerator generation mechanism using water electrification and inertia. </LI> <LI> Optimization of the dimension and operating conditions for the nanogenerator using nondimensional factor G. </LI> <LI> A multiphase dynamic numerical simulation for water energy harvesting. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

지능형 타이어 센서를 이용한 섀시통합제어

정태영(Taeyoung Chung),황태훈(Taehun Hwang) 한국자동차공학회 2012 오토저널 Vol.34 No.9