Vacuum Squeeze 조형기(造型機)

박성하,안주수 한국주조공학회 1988 한국주조공학회지 Vol.8 No.2

의정부 공동주택화재사고를 통한 외장재화재성상의 역학적해석에 관한 연구

박성하?구인혁?권영진 한국화재소방학회 2015 한국화재소방학회 학술대회 논문집 Vol.2015 No.추계

목 자세에 따른 선 자세에서의 신체균형능력 평가

박성하 한국산업경영시스템학회 2018 한국산업경영시스템학회지 Vol.41 No.2

Postural instability can increase the likelihood of hazardous slip and fall accidents in workplaces. The present study intended to extend understanding of the effect of abnormal neck posture on postural control during quiet standing. The effect of body fatigue on the postural control was also of primary concern. Twelve healthy undergraduate students volunteered to participate in the experiment. Standing on a force platform with the neck neutral, flexed, extended, or rotated, subjects’ center of pressures (COP) were measured under the two levels of body fatigue. For the fatigue condition, Subjects exercised in a treadmill to meet the predetermined level of body fatigue. Analyzing the position coordinates of COPs, the length of postural sway path was assessed in both medio-lateral (ML) axis and anterior-posterior (AP) axis. Results showed that, in AP direction, neck extension or rotation significantly increased the sway length as compared with neck neutral. Neck extension led to greater sway length compared to neck rotation. Neck flexion did not differ from neck neutral. The sway length in the AP direction also became significantly larger as the body fatigue accumulated after treadmill exercise. In ML direction, as compared to neutral posture, the neck extension, flexion, or rotation did not significantly affect the length of postural sway path. However, the sway length seemed to increase marginally with the neck extended during the fatigued condition. This study demonstrates that abnormal neck posture may interfere with postural control during standing. The ability to maintain postural stability decreases significantly with the neck extended or rotated. Body fatigue leads to postural instability further.

Molybdenum sulfide 촉매상에서 중질유의 탈황반응과 탈질반응의 상호작용

정원모,전상문,박성하 大田工業大學 1989 한밭대학교 논문집 Vol.6 No.2

ABSTRACT Interactions between hydrodesulfurization of thiophene and hydrodenitrogena- tion of pyridine in heavy coker oil were studied over sulfided Co-Mo/γ-Al2 O3 and Ni-Mo/γ-Al2 O3 catalysts. The ranges of operating conditions were at the temperatures between 423 and 723K, the pressures between 10 x 105 and 50 x 105 Pa, H2/thiophen, pyridine mole ratio 300 and the contact times between 0.015 and 0.03 gcat.hr/ml feed respectively, Thiophene hydrodesulfurization was inhibited by the presence of pyridine at all temperatures and pressures. Pyridine hydrodenitrogenation was inhibited at low temperatures but enhanced by the thiophene at high temperatures (above 623K) and the formation of piperidine greately decreased with the addition of thiophene at all temperatures and pressures. Co-Mo/γ-Al2 O3 appeared to have greater activity than Ni-Mo/y-Alz 03 appeared to have greater activity than Co-Mo/γ-Al2 O3 for pure pyridine and mixed feed hydrodenitrogenations. Interactions between hydrodesulfurization of thiophene and hydrodenitrogenation of pyridine in heavy coker oil were studied over sulfided Co-Mo/γ-Al_2O_3 and Ni-Mo/γ-Al_2O_3 catalysts. The ranges of operating conditions were at the temperatures between 423 and 723K, the pressures between 10 × 10^5 and 50 × 10^5 Pa, H_2/thiophen, pyridine mole ratio 300 and the contact times between 0.015 and 0.03 gcat.hr/ml feed respectively. Thiophene hydrodesulfurization was inhibited by the presence of pyridine at all temperatures and pressures. Pyridine hydrodenitrogenation was inhibited at low temperatures but enhanced by the thiophene at high temperatures (above 623K) and the formation of piperidine greately decreased with the addition of thiophene at all temperatures and pressures. Co-Mo/γ-Al_2O_3 appeared to have greater activity than Ni-Mo/γ-Al_2O_3 appeared to have greater activity than Co-Mo/γ-Al_2O_3 for pure pyridine and mixed feed hydrodenitrogenations.

연속교반 반응기를 사용한 Bitumen의 수첨접촉분해

박성하 大田産業大學校 1997 한밭대학교 논문집 Vol.14 No.1

Bitumen by catalytic hydrocracking was studied in CSTR(Continous Stirred Tank Reaetor) with conventional catalysts of Mo-Co/Al_2O_3 and Ni-Mo/Al_2O_3. In the hydrocraching of bitumen, the kind of catalysts did not seem to influence the distribution of gaseous products in which C_3 and C_4 fraction were predomine-nt, whereas C_1 and C_2 fractions in noncatalytic cracking. In the liquid products, naphtha fraction was increased with temperature, whereas fuel oil fraction was decreased. The distillate fraction was relatively Invariant wi-th respect to temperature. The amount of hydrogen consumed increased with temperature and resisdence ti-me, however, it was very same even when the catalysts are present or not. The formation of coke in the hydrocracking ocurred at a temperature larger than 440 ℃ and LHSY less than 1.

Fabrication methods and applications of DNA nanostructures

박성하 한국고분자학회 2013 한국고분자학회 학술대회 연구논문 초록집 Vol.2013 No.4

DNA Nanostructures and their Applications

박성하 한국고분자학회 2015 한국고분자학회 학술대회 연구논문 초록집 Vol.2015 No.10

Geant4를 이용한 STEIN 검출기의 입자 분리 검출 모의실험 예비 결과 분석

박성하,김용호,우주,선종호,진호,이동훈,Park, Seong-Ha,Kim, Yong-Ho,U, Ju,Seon, Jong-Ho,Jin, Ho,Lee, Dong-Hun 한국천문학회 2012 天文學會報 Vol.37 No.2

지구 자기권에 존재하는 플라즈마 입자의 다중관측을 목적으로 개발된 초소형 탑재체 STEIN (SupraThermal Electron, Ion, Neutral) 은 경희대학교와 UC Berkeley가 공동으로 개발 중인 3대의 초소형 과학위성 TRIO-CINEMA (TRiplet Ionosphere Observatory - Cubesat for Ion, Neutral, Electron and MAgnetic fields) 에 탑재될 입자 검출기이다. 32개의 픽셀로 이루어진 STEIN 검출기는 2~300 keV의 전자, 4~300 keV의 이온과 중성입자(Energetic Neutral Atom: ENA) 를 분리 계측할 목적으로 설계되었으며, 하전입자가 정전장 편향기를 통과하여 서로 다른 검출기 픽셀에 도달함으로써 전자와 이온, 중성입자를 분리하여 계측할 수 있도록 하였다. 한편, STEIN 구조물에서 발생한 2차 입자의 검출을 방지하기 위해 정전 편향기 사이에 차단날(blade)을 설계하였다. 본 연구에서는 STEIN 모의실험 예비 결과로써 전기장에 크기 및 차단날에 의한 하전입자의 궤적과 이에 따른 분리 계측 성능을 알아보고자 Geant4 (GEometry ANd Tracking)를 사용하여 검출기 픽셀에 입사하는 전자의 초기 위치를 분석하였다. 전자의 입사 위치는 검출기로부터 5 cm 전방에서 6 mm * 20 mm 범위 내에서 무작위로 생성하여 검출기의 방향으로 수직 입사하였다. 분석 결과 전자들은 전기장의 방향에 따라 편향되는 결과를 보였으며, 저에너지 전자는 강한 전기장의 영향으로 차단날에 의해 차폐되어 검출되지 않았다. 따라서 전기장의 크기와 차단날에 따른 입자 분리 검출이 가능함을 본 모의실험을 통해 확인하였으며, STEIN 운용 시 입자 분리 검출 및 결과 분석 기반으로 본 연구 결과를 사용될 수 있을 것으로 기대된다.

Role of Inflammation in the Pathogenesis of Arterial Stiffness

박성하,Edward G. Lakatta 연세대학교의과대학 2012 Yonsei medical journal Vol.53 No.2

Increased arterial stiffness is an independent predictor of cardiovascular disease independent from blood pressure. Recent studies have shed new light on the importance of inflammation on the pathogenesis of arterial stiffness. Arterial stiffness is associated with the increased activity of angiotensin II, which results in increased NADPH oxidase activity, reduced NO bioavailability and increased production of reactive oxygen species. Angiotensin II signaling activates matrix metalloproteinases (MMPs) which degrade TGFβ precursors to produce active TGFβ, which then results in increased arterial fibrosis. Angiotensin II signaling also activates cytokines, including monocyte chemoattractant protein-1, TNF-α, interleukin-1, interleukin-17 and interleukin-6. There is also ample clinical evidence that demonstrates the association of inflammation with increased arterial stiffness. Recent studies have shown that reductions in inflammation can reduce arterial stiffness. In patients with rheumatoid arthritis,increased aortic pulse wave velocity in patients was significantly reduced by anti tumor necrosis factor-α therapy. Among the major classes of anti hypertensive drugs, drugs that block the activation of the RAS system may be more effective in reducing the progression of arterial stiffness. Thus, there is rationale for targeting specific inflammatory pathways involved in arterial stiffness in the development of future drugs. Understanding the role of inflammation in the pathogenesis of arterial stiffness is important to understanding the complex puzzle that is the pathophysiology of arterial stiffening and may be important for future development of novel treatments.

ARTIFICIALLY DESIGNED DNA NANOSTRUCTURES

박성하,RASHID AMIN,SOYEON KIM,THOMAS HENRY LABEAN 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2009 NANO Vol.4 No.3

In the field of structural DNA nanotechnology, researchers create artificial DNA sequences to self-assemble into target molecular superstructures and nanostructures. The well-understood Watson–Crick base-pairing rules are used to encode assembly instructions directly into the DNA molecules. A wide variety of complex nanostructures has been created using this method. DNA directed self-assembly is now being adapted for use in the nanofabrication of functional structures for use in electronics, photonics, and medical applications.