LoRa LPWAN 기반의 대형 교량 구조건전성 모니터링 시스템

박진오,김기돈,김경수,박상헌 한국전산구조공학회 2023 한국전산구조공학회논문집 Vol.36 No.1

With the development of technology worldwide, bridges are becoming larger, and the number of old bridges is also rapidly increasing. Monitoring the structural health of large, aging bridges is essential to preventing large-scale accidents. In this study, the application of a LoRa low-power wide-area network (LPWAN)-based wireless measurement system was investigated, and a LoRa wireless measurement system was established in the cable-stayed bridge section of Cheonsa Bridge, located in Shinan-gun, Jeollanam-do, Korea. The applicability of the LoRa LPWAN-based wireless monitoring system to large marine bridges was reviewed by comparing the performance and economic feasibility with wire-based monitoring systems that were built and operated by establishing a measurement system for the pylons, cables, and reinforcing girders of the bridge.

Dependence of Photothermal Responses on Wavelengths

박진오,표한재,최종만,정석,강현욱 한국물리학회 2019 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.74 No.3

The goal of the current research is to identify dependence of photothermal responses on wave- lengths for diuser-assisted treatment of liver tumor. For interstitial photothermal treatment, four commercially available wavelengths were tested: 532, 808, 980, and 1470 nm. A thermal camera was employed to record spatio-temporal development of temperature in porcine liver tissue. Spatial dis- tribution of temperature and coagulation was quantitatively evaluated at various irradiation times. Both 808 and 980 nm presented a comparable maximum temperature after delivery of 200 J. On the other hand, both 532 and 1470 nm induced the higher maximum temperatures of over 90 C along with a wider thermal distribution. The degree of the coagulation for both 532 and 1470 nm was quite consistent along the diusing tip as various distances showed the comparable coagulation thickness. Both 808 and 980 nm presented the varying degree of the coagulation (1 2 mm in thickness). The largest volume along the thickest radial coagulation was observed after 1470 nm laser irradiation (606:9 21:0 mm3) whereas the smallest volume was created by 980 nm (77:1 13:3 mm3). The current results demonstrated that due to strong light absorption, both 532 and 1470 nm could be the feasible wavelengths for the treatment of liver tumor.

CO2 curing effects of concrete products made using fly ash and blast furnace slag

박진오,이종찬,이세현 한양대학교 세라믹연구소 2016 Journal of Ceramic Processing Research Vol.17 No.9

In order to analyze the effects of fly ash and blast furnace slag on CO2 uptake and compressive strengths in CO2 curing, twotests were carried out. First, the compressive strength test of a non CO2 cured specimen and a specimen with W/C 30% and20% admixture was conducted at three hours and three days while curing in a chamber with 20 oC and RH 60% after CO2curing for an hour. Second, the compressive strength test of a non CO2 cured specimen and a specimen with W/C 35-40% and10% admixture was conducted at 7 days and 28 days while curing in chamber with 60 oC and RH 100% after steam curingat 20 oC and RH 60% and CO2 curing for 2 hrs. In the first test results, the CO2 uptake rate of the case with 20% of admixturewas found to be 2% lower than the case without admixture, and CO2 curing turned out to be very effective in increasing theearly compressive strength. The second test results showed that CO2 uptake rate of the case with fly ash and blast furnace slagwas found to be similar with the case without admixture. Even in terms of increasing the compressive strength, CO2 curingof two hours was found to exhibit a similar strength development effect to steam curing of 4 hrs.

Early labechiid stromatoporoids of the Yeongheung Formation (Middle Ordovician), Yeongwol Group, mideastern Korean Peninsula: Part I. Environmental distribution

박진오,홍종선,이정현,조석주,이동진 한국지질과학협의회 2017 Geosciences Journal Vol.21 No.3

This study examines depositional facies and environmental significance of early labechiid stromatoporoids in the Yeongheung Formation (late Middle Ordovician), Yeongwol Group in the mideastern part of the Korean Peninsula. The formation is composed of five depositional facies: lime mudstone to wackestone (LM/W), peloidal, intraclastic and bioclastic packstone to grainstone (P/G), laminated dolomitic lime mudstone (LMdl), algal laminite (La), and oolitic packstone to grainstone (P/Go). Three types of shallowing upward cycles in the succession are identified, including subtidal (LM/W–P/G), subtidal to peritidal (LM/W–P/G–LMdl–La), and peritidal cycles (LMdl–La). The stromatoporoids occur exclusively in the packstone to grainstone (P/G) facies of the subtidal cycle. These early labechiids inhabited on a grainy substrate under moderate- to high-energy conditions, conforming to the previous notion that stromatoporoids primarily occupied level-bottom or reefs, surrounded by grainy calcareous sediments during the Middle Ordovician.

LoRa LPWAN 무선 통신을 활용한 교량 유지관리 시스템 적용성 연구

박진오,박상헌,안승주,박원주,김종훈 한국구조물진단유지관리공학회 2019 한국구조물진단유지관리공학회지 Vol.23 No.2

인공발목관절의 임상시험 가이드라인 개발을 위한 문헌적 고찰

박진오,이모세,이진우,이수빈,한승환,Park, Jin Oh,Lee, Moses,Lee, Jin Woo,Lee, Soo Bin,Han, Seung Hwan 대한족부족관절학회 2014 대한족부족관절학회지 Vol.18 No.4

Purpose: The purpose of this study is to develop guidelines for clinical trial of the total ankle replacement system for premarket approval. Materials and Methods: We selected and analyzed nine peer-reviewed articles whose quality had been proven in a previous phase. Two investigators extracted parameters for guideline criteria, including number of cases, patient age, follow-up period, failure rate, radiographic osteolysis rate, residual pain rate, and percentage of satisfaction. In addition, the inclusion and exclusion criteria were analyzed and developed. Results: Eight level IV studies and one level II study were included. The average number of cases was 159 cases and the mean patient age was 63.5 years. The mean follow-up period was 4.2 years, ranging from two to nine. The average failure rate of total ankle replacement in mid- to long-term follow-up was approximately 13% (2%~32.3%). The rate of osteolysis was approximately 18%. Residual pain was common (21.4%~46%), but overall patient satisfaction was approximately 85.6% (67.5%~97%). Conclusion: The results could be used as criteria for designing the clinical studies, such as number of cases, patient age (over 60 years), and follow-up period (minimum two years). The clinical scoring system and 36-item short form health survey (SF-36) was the most commonly used method for clinical evaluation for total ankle arthroplasty. In addition, the overall results, including failure rate, osteolysis rate, and patient satisfaction, could be used as a parameter of guidelines for premarket approval.

영월군 남애 지질단면에 분포하는 영월층군: 서부 태백산 분지 상부 캄브리아계-하부 오르도비스계 퇴적층의 암층서 개선과 그 지질학적 중요성

박진오,홍종선,김대철,이정호,성예지 대한지질학회 2024 지질학회지 Vol.60 No.1

Stratigraphic understanding of the Yeongwol Group in a western division of the Taebaeksan Basin remains unclear due largely to development of complex thrust faults and extensive dolomitization. This study aims to describe lithostratigraphic features of the Namae section, where the upper Cambrian to Lower Ordovician sedimentary successions are continuously exposed without structural discontinuities, and to shed light on their geological values with an emphasis on refinement of lithostratigraphic units and boundaries. The Yeongwol Group in the Namae section consists of the uppermost Machari (14.5 m), Wagok (171 m), Mungok (189.5 m), and lower Yeongheung (38 m) formations in ascending order. This section is the only site to date where three lithostratigraphic boundaries between the formations can be observed in one place. In this section, two lithostratigraphic intervals, including an entire succession of the Wagok Formation and a transitional interval from the upper Mungok to the lower Yeongheung formations, were newly identified. Although the Wagok Formation is mainly composed of massive dolostone, sedimentary structure, carbonate grains, and fossil skeletons are partly preserved in the lower and upper intervals of the formation, allowing us for further paleontologic, stratigraphic, and sedimentologic researches. In addition, the Namae section provides a lithostratigraphic standard for the boundary between the Mungok and Yeongheung formations, which has been ambiguously defined or misinterpreted in previous works. It reveals how and when the peritidal carbonate depositional system of the Yeongheung Formation developed in this region.

LoRa 센서네트워크 기반의 무선교량유지관리 시스템 구축

박진오,박상헌,김경수,박원주,김종훈 한국전산구조공학회 2020 한국전산구조공학회논문집 Vol.33 No.2

The IoT-based sensor network is one of the methods that can be efficiently applied to maintain the facilities, such as bridges, at a low cost. Inthis study, based on LoRa LPWAN, one of the IoT communications, sensor board for cable tension monitoring, data acquisition board forconstructing sensor network along with existing measurement sensors, are developed to create bridge structural health monitoring system. Inaddition, we designed and manufactured a smart sensor node for LoRa communication and established a sensor network for monitoring. Further, we constructed a test bed at the Yeonggwang Bridge to verify the performance of the system. The test bed verification resultssuggested that the LoRa LPWAN-based sensor network can be applied as one of the technologies for monitoring the bridge structuresoundness; this is excellent in terms of data rate, accuracy, and economy. 사물인터넷 기반의 센서네트워크는 저렴한 비용으로 효율적으로 교량 등의 시설물 유지관리에 적용할 수 있는 한 방안이다. 본 연구에서는 사물인터넷 통신의 하나인, LoRa LPWAN 기반으로 교량 구조건전성모니터링을 위한 시스템을 개발하기 위해서 케이블 장력 모니터링을 위한 센서보드, 기존 계측 센서들과 함께 센서네트워크를 구축하기 위한 DAQ 보드, 데이터들 처리하고 LoRa 통신을위한 스마트센서노드를 설계 및 제작하였으며 모니터링을 위한 센서네트워크를 구축하였다. 또한 본 시스템의 성능검증을 위해 영광대교에 Test Bed를 구축하여 교량 구조건전성 모니터링을 위한 센서네트워크에 적용가능성 여부를 살펴보았다. Test Bed 검증 결과LoRa LPWAN 기반 센서네트워크는 데이터 전송률, 정확도, 경제성면에서 교량 구조 건전성 모니터링의 기술 중에 하나로 적용될 수있으며, 향후 교량구조물 뿐만 아니라 다양한 공공기반 시설물에 유지관리를 위한 시스템으로 보급될 수 있기를 기대한다.

전립선농양의 임상적 특성

박진오,윤덕기 大韓泌尿器科學會 1999 Korean Journal of Urology Vol.40 No.1

퇴적환경 변화와 생물초 구성생물의 분포 : 후기 오르도비스기 시아쯘층의 예

박진오,조석주,이동찬,이동진 한국고생물학회 2012 한국고생물학회 정기총회 및 학술발표회 Vol.2012 No.2