광생물반응기의 CO₂ 공급 멤브레인의 최적 조건 도출을 위한 실험적 연구

김하늘,이재환,최은지,오유관,김정배,Kim, H.N.,Lee, J.H.,Choi, E.J.,Oh, Y.G.,Kim, Jeongbae 한국액체미립화학회 2014 한국액체미립화학회지 Vol.19 No.3

This study was performed to reveal the relationships between various gas supply conditions including inlet numbers and positions for Photobioreactor. To do that, this study was installed the experimental apparatus. All experiments were performed for the cases with 1, 2, 3, and 4 inlets and for gas flow rate of 4~8 lpm. Through the experiments, this study showed that the case with 3 or 4 inlets could reduce about 50% of the pressure loss head for all gas path than that of one inlet base case. So, these results can be used as basic data to design the gross or multiple photobioreactor.

대전방지용 Al₂O₃-SiC 복합세라믹 소결체의 제조 및 특성

김하늘,오현명,박영조,고재웅,이현권,Kim, Ha-Neul,Oh, Hyun-Myung,Park, Young-Jo,Ko, Jae-Woong,Lee, Hyun-Kwuon 한국분말야금학회 2018 한국분말재료학회지 (KPMI) Vol.25 No.2

$Al_2O_3-SiC$ ceramic composites are produced using pressureless sintering, and their plasma resistance, electrical resistance, and mechanical properties are evaluated to confirm their applicability as electrostatic-discharge-safe components for semiconductor devices. Through the addition of Mg and Y nitrate sintering aids, it is confirmed that even if SiC content exceeded 10%, complete densification is possible by pressureless sintering. By the uniform distribution of SiC, the total grain growth is suppressed to about $1{\mu}m$; thus an $Al_2O_3-SiC$ sintered body with a high strength over 600 MPa is obtained. The optimum amount of SiC to satisfy all the desired properties of electrostatic-discharge-safe ceramic components is obtained by finding the correlation between the plasma resistance and the electrical resistivity as a function of SiC amount.

선형 프레넬 반사판 태양열 발전시스템의 설계 및 제작

김하늘,김종규,Kim, Haneol,Kim, Jongkyu 한국교통대학교 융복합기술연구소 2018 융ㆍ복합기술연구소 논문집 Vol.8 No.1

In this study, design and manufacture of LFR (Linerar Fresnel Reflector) system was performed for solar thermal absorption cooling. The LFR system was designed considering the expansion and convenience to be installed according to the cooling capacity of the applicable building. Twelve LFR modules with a total reflection area of $204m^2$ were installed. The automatic tracking system was applied to track the sun during the daytime.

운동 전 적용된 지속초음파와 맥동초음파가 운동 유발성 근육 손상의 통증과 근피로대사산물에 미치는 효과

김하늘,전재근,신성필,Kim, Ha Neul,Jeon, Jae Geun,Shin, Sung Phil 대한물리치료과학회 2020 대한물리치료과학회지 Vol.27 No.3

Background: The purpose of this study was to investigate the effects of pulsed-ultrasound intervention and continued-ultrasound on the PPT (pressure pain threshold), CK (creatine kinase) and LDH (lactate dehydrogenase) recovery of before EIMD (exercise-induced muscle damage). Design: Randomized Controlled Trial. Methods: Thirty subjects who are student in their 20s at a university participated in this study, these subjects were assigned into three groups, a control group (n=10), experiment group I (n=10), and experiment group II (n=10). The subjects in experimental group were intervened by pulsed-ultrasound and continued-ultrasound, while ones on control group weren't by any intervention after induced EIMD. Results: First, In the comparison of the PPT, there were significant variations with the lapse the time in three groups (p<.001) and there was a significant interaction of time and group (p<.001). In the among group comparison, the PPT of experimental group II was significantly larger than those of other groups (p<.01). Second, In the comparison of the CK, there were significant variations with the lapse the time in three groups (p<.001) and there was a significant interaction of time and group (p<.001). In the among group comparison, the CK of experimental group II was significantly smaller than those of other groups (p<.001). Third, In the comparison of the LDH, there were significant variations with the lapse the time in three groups (p<.001) and there was a significant interaction of time and group (p<.001). In the among group comparison, the LDH of experimental group II was significantly smaller than those of other groups (p<.001). Conclusion: The above results revealed that the continued-ultrasound intervention before an exercise had a positive effect of muscle function after EIMD. Therefore we can consider the continued ultrasound as a considerable intervention method to prevent or reduce an exercise injury.

한국형 데이터 시각화 리터러시 평가 개발 및 연구 동향 분석

김하늘,김성희,Kim, Ha-Neul,Kim, Sung-Hee 한국정보통신학회 2021 한국정보통신학회논문지 Vol.25 No.11

최근 정보 기술의 성장에 따라 디지털, 데이터, 인공지능 리터러시와 같은 다양한 리터러시에 대한 연구가 이루어지고 있다. 본 논문에서는, 빅데이터 분석에서 필수적이고, 일상생활 모바일 앱에서도 다양하게 쓰이는 데이터 시각화에 초점을 두고 있으며, 데이터 시각화 활용 능력을 측정하는 데이터 시각화 리터러시 평가 체계에 대해서 다룬다. 2016년에 개발된 영문형 데이터 시각화 활용 능력을 측정하는 평가 체계(VLAT, Visualization Literacy Assessment Test)에 대해서 설명하고, 한국형에 맞춰 개발한 K-VLAT 평가 체계를 소개한다. K-VLAT은 국내 사용자의 맥락에 맞춰 12개의 시각화와 53개의 문항을 웹서비스를 통해 제공한다. 또한, 데이터 시각화 리터러시의 연구 방향을 이해하기 위해서, 영문형 VLAT을 참조한 79건의 논문을 분석하였다. 연구 목적을 4개의 대분야 및 11개의 소분야로 분류하였으며, 데이터 시각화 리터러시와 관련한 인지, 체계에 대한 확장, 교육과의 연계, 사용자 중심형 대시보드 개발 및 효과 평가 등에 활용되고 있다. 이에 따른 K-VLAT의 향후 활용 방안에 대해서 논의한다. With the recent growth of information technology, various literacy such as digital literacy, data literacy, AI literacy is being studied. In this paper, we focus on data visualization literacy as visualization is an essential part of big data analysis and is used in several mobile apps. Visualization Literacy Assessment Test(VLAT) was developed in 2016 and we introduce how the test was developed and modified to a Korean version, K-VLAT. K-VLAT is consisted of 12 visualizations and 53 questions through a website. Additionally, to understand the research trend in visualization literacy we analyzed 81 papers that had cited the VLAT publication. We categorized the research into 4 categories with 11 sub-categories. The area of studies visualization literacy related to was understanding the relation with cognition, expanding the literacy measures, relation with education, utilization for developing user-centric dashboards or using the test to show effectiveness of visualizations. At last, we discuss about different ways to utilize K-VLAT for future research.

운동 전 적용된 지속초음파와 맥동초음파가 운동 유발성 근육 손상의 최대등척성근력과 관절가동범위에 미치는 효과

김하늘,전재근,신성필,Kim, Ha Neul,Jeon, Jae Geun,Shin, Sung Phil 대한물리치료과학회 2021 대한물리치료과학회지 Vol.28 No.2

Background: The purpose of this study was to investigate the effects of pulsed-ultrasound intervention and continued-ultrasound on the MVIC (maximal voluntary isometric contraction) and active ROM (range of motion) recovery of before EIMD (exercise-induced muscle damage). Design: Randomized controlled trial. Methods: Thirty subjects who are student in their 20s at a university participated in this study, these subjects were assigned into three groups, a control group (n=10), experiment group I (n=10) and experiment group II (n=10). The subjects in experimental group were intervened by pulsed-ultrasound and continued-ultrasound, while ones on control group weren't by any intervention after induced EIMD. Results: First, In comparison of the MVIC, in the among group comparison, the MVIC of continued-ultrasound group was significantly larger than those of other groups (p<.005). Second, In the among group comparison, the active extension angle of continued-ultrasound group was significantly smaller than those of other groups (p<.005). Third, In the among group comparison, the active flexion angle of continued-ultrasound group was significantly lager than those of other groups (p<.05). Conclusion: The above results revealed that the continued-ultrasound intervention before an exercise had a significantly improve of muscle function after EIMD. Therefore we can consider the continued ultrasound as a considerable intervention method to prevent or reduce an exercise injury.

편측 요통을 호소하는 환자에 있어서 척추 주위 근육의 지방량과 통증과의 관계

김하늘 ( Ha Neul Kim ),김경훈 ( Kyoung Hun Kim ),김주원 ( Joo Won Kim ),진은석 ( Eun Seok Jin ),하인혁 ( In Hyuk Ha ),고동현 ( Dong Hyun Koh ),홍순성 ( Soon Sung Hong ),권혁준 ( Hyeok Joon Kwon ) 한방재활의학과학회 2009 한방재활의학과학회지 Vol.19 No.1

목적: 요통은 임상에서 가장 흔하게 접할 수 있는 질환이며, 동시에 통증으로 인한 근무 결손도나 생활 불편감이 높은 질병이다. 그래서, 많은 연구들이 요통을 일으키는 원인 혹은 악화시키는 유발 인자를 밝혀내려는데 초점이 맞추어져 있다. 이번 연구의 목적은 편측 요통을 호소하는 환자에 있어서 MRI에서 조사된 척추 주위 근육의 지방량과 통증과의 관계에 대해서 알아보는데 있다. 방법: 2007년 11월부터 2008년 4월까지 본원에 요통으로 내원한 환자를 대상으로, 편측 요통을 호소하며, 체질량 지수가 25kg/㎡ 이하이며, 만 20세이상 40세미만인 환자 24명을 대상으로 연구를 진행하였다. MRI에서 조사되어진 L4-5 디스크 레벨의 척추 주위 근육의 지방량을 객관적인 pseudocoloring technique을 이용해 측정하고, paired t-test로 결과를 분석하여 요통이 유발된 측과 지방량의 관계에 대해서 연구하였다. 결과: 요통이 있는 측의 지방량과 요통이 없는 측의 지방량을 측정하여 데이터를 분석하였다. 양측의 지방량과 통증의 유무에 대한 관계는 통계적으로 유의한 수치를 나타냈다(P <0.05). 요통이 있는 측과 없는 측과의 성별, 나이, BMI의 통계적인 차이는 없었으며, 지방량 측정시 남자들이 여자들에 비해 지방량이 더 높게 측정되었다(남자 8.5±5.1%, 여자 6.5±3.6%). 결론: 이 연구를 통해 척추 주위 근육의 지방량과 요통에 대한 상관성의 증거를 제시하였다. 잘 선별되어진 환자의 MRI를 통해 객관적인 방법으로 지방량을 체크를 하였으며, 추후 더 많은 개체수를 이용해 보다 더 정확한 관련성을 파악하고, 나아가 지방량에 따른 통증 강도의 상관성에 대해서 연구가 필요하리라 생각된다. Objectives: Low back pain(LBP) is a common disabling disease in clinical practice and loss of working hours due to this condition is huge. The aim of this study was to determine if there was an association between fat deposit of paraspinal muscles as observed on MRI scans in patients presenting with unilateral LBP. Methods: 24 patients who visiting our hospital with a clinical presentation of unilateral LBP were recruited to the study. Patients were between 20 and 30 years and had a history of unilateral LBP within 12 months. After MRI scaning, the images were saved in DICOM file format for Picture Archiving and Communication System(PACS). The percentage of fat infiltrated area was measured using a pseudocoloring technique. Data were analyzed comparing the fat deposits of the muscles on the symptomatic and asymptomatic sides. Paired t-test was used to find the difference between the measurements of fat tissue in individual patients. Results: The amount of fat in the symptomatic side was 7.6±4.51%, asymptomatic side was 6.7±4.29%. There were increases, statistically significant, in the fat changes of the paraspinal muscles at the L4-5 disc level(P <0.05). Also, men were likely than women to have more fat deposit in symptomatic side(men 8.5±5.1%, women 6.5±3.6%). Conclusions: The amount of fat in the symptomatic side shows significantly increased than asymptomatic side in the paraspinal muscles at the L4-5 disc level. It suggested that fat infiltration in the muscles associated with LBP. Further studies will be needed to confirm the relationship between the muscle fatty changes and LBP in the large sample size. In addition, the correlation of pain severity with fat infiltration needs to be addressed.

바이오메탄 분해 수소생산을 위한 태양열이용 반응기 개발 및 실험

김하늘(Haneol Kim),이상남(Sangnam Lee),김학주(Hakjoo Kim),김종규(Jongkyu Kim) 한국신재생에너지학회 2021 한국신재생에너지학회 학술대회논문집 Vol.2021 No.7

본 연구에서는 태양열을 이용하여 바이오 가스 내의 메탄을 수소와 카본 블랙으로 분해하기 위해 단계적으로 반응기를 개발하고 실험을 수행하였다. 초기 쿼츠가 장착된 직접가열식 반응기를 개발하였으나 카본 침착에 따른 쿼츠 파손이 발생하였다. 이에 단계적 개선을 통해 최종적으로 컴팩트 캐비티가 적용된 원통형의 간접가열식 반응기를 개발하였다. 메탄 분해 시 반응 온도 및 활성화 에너지를 낮추기 위해 두께 9.5 mm인 NiCrAl 메달 폼 지지체에 바인더를 통해 카본 파우더가 코팅된 촉매를 사용하였다. 집광된 태양열을 반응기에 공급하기 위해 헬리오스타트, 블라인드, 접시형 집광기로 구성된 한국에너지기술연구원의 40 kWth 태양로를 사용하였다. 반응기를 이용한 실험을 통해 메탄 유량이 20L/min, 40 L/min일 때 각각 평균 96.7%, 89.0%의 메탄-수소 전환율을 달성하였다.

태양열 이용 메탄 분해 수소 생산 실험

김하늘(Haneol Kim),이상남(Sangnam Lee),김학주(Hakjoo Kim),김종규(Jongkyu Kim) 한국태양에너지학회 2021 한국태양에너지학회 학술대회논문집 Vol.2021 No.5

5성분계 용융염 열전달 특성 연구

김하늘(Ha Neol Kim),서태범(Tae Beom Seo),김홍수(Hong Soo Kim),윤환기(Hwan Ki Yoon),이상남(Sang Nam Lee),김종규(Jong Kyu Kim) 대한기계학회 2016 대한기계학회 춘추학술대회 Vol.2016 No.4