• Journal of Magnetics
• /
• 제18권2호
• /
• pp.188-191
• /
• 2013

The magnetic properties for sanal's mobility inside of the lymphatic primo vascular system, the so-called Kyungrak (or meridian) system, are investigated under a low static magnetic field with the anatomy technology and optical microscope. One sanal with a size of 1 ${\mu}m$ under microscope selected and separated from the primo vessels of the primo vascular system are observed in rabbits' lymphatic vessels around abdominal aorta and placed in PBS solution with petridish. The moving displacement of sanal versus the measuring time of 20 Oe below a magnetic field of 80 Oe is stronger in dominanting dependence according to the x-direction than y-direction.

• Journal of Acupuncture & Meridian Studies
• /
• 제11권6호
• /
• pp.381-381
• /
• 2018

• Journal of Acupuncture & Meridian Studies
• /
• 제11권6호
• /
• pp.382-390
• /
• 2018

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2005년도 창립60주년 기념 추계 학술대회
• /
• pp.83.2-83.2
• /
• 2005

• 한국자기학회지
• /
• 제21권6호
• /
• pp.219-224
• /
• 2011

해부학적 기술로 경락의 실체인 프리모 시스템 내에 존재하는 산알을 획득하여 운동 모습을 광학 현미경으로 분석하였고, 낮은 정자기장하에서 운동 특성을 조사하였다. 토끼 장기 표면으로부터 산알이 다량으로 몰려있는 프리모 소체 내에 약 1 ${\mu}m$ 정도 크기의 산알들을 선택 및 분리시켜, 패트리 디쉬 안에 PBS 용액과 산알을 담았다. 내부 온도 $38^{\circ}C$, 100 Oe 이하 일정한 외부 자기장에 평행방향과 수직방향으로 움직이는 산알의 운동속도를 관찰하였다. 평행방향 외부 자기장이 0 Oe에서 80 Oe까지 20 Oe 증가함에 따라 5개 산알 중 4개는 약 0.9 pixel/s의 평균속도로 감소하는 뚜렷한 경향성을 갖고 있음을 볼 수 있었다. 반면에 수직 방향으로 운동하는 산알의 경우, 외부 자기장이 없을 때와 비슷한 무작위로 운동함을 관찰하였다. 이러한 실험결과로부터 산알 핵 DNA내에 망간(Mn)과 코발트(Co) 등의 다량의 무기물을 함유하는 산알이 회전운동을 하면서 움직일 때, 외부 자기장을 인가함으로써 운동 특성을 약화시키는 자기적 특성이 있는 것으로 사료되었다.

• 한국자기학회:학술대회 개요집
• /
• 한국자기학회 2012년도 임시총회 및 하계학술연구발표회
• /
• pp.23-25
• /
• 2012

• 한국추진공학회:학술대회논문집
• /
• 한국추진공학회 2005년도 제24회 춘계학술대회논문집
• /
• pp.57-60
• /
• 2005

A diagnostic investigation is carried out to examine the igniter jet turbulence effects on the internal ballistics of solid rocket motors with divergent port. The numerical studies have been carried out with the help of a two dimensional k-omega turbulence model. It was inferred that increasing the igniter jet turbulence intensity is a possible way to decrease the pressure spike and pressurization rate, marginally during the ignition transient, by altering the location of the secondary ignition in solid rocket motors with non-uniform port.

• 한국추진공학회:학술대회논문집
• /
• 한국추진공학회 2003년도 제21회 추계학술대회 논문집
• /
• pp.6-10
• /
• 2003

Accurate description of starting transient history allows and justifies the use of small margin of safety for the engine parts, resulting in high motor mass ratio in addition to satisfying the control and guidance requirements of the vehicle. Studies have been carried out for the prediction and reduction of ignition peak and pressure-rise rate during the starting transient of solid rocket motors. Numerical studies have been carried out using a two dimensional Navier-Stokes solver. It has been inferred through the parametric studies that, in the case of solid rocket motors with uniform port, high ignition peak is observed at high spread rate and low pressure-rise rate. In the case of the port with sudden expansion configuration, high ignition peak is observed at relatively high average spread rate and high-pressure rise rate. These studies are expected to aid the designer in reducing the ignition peak by altering the propellant properties or igniter characteristics without sacrificing the motor performance.

• 한국추진공학회:학술대회논문집
• /
• 한국추진공학회 2004년도 제22회 춘계학술대회논문집
• /
• pp.550-559
• /
• 2004

Theoretical studies have been carried out to examine the influence of the grain geometry-dependent driving forces, which control the internal flow pattern of solid rockets. Numerical studies have been executed with the help of a two-dimensional code. This code solves standard k-omega turbulence equations using the coupled second order implicit unsteady formulation. It has been concluded that the grain port divergence angles have significant leverage on the formation of recirculation bubbles leading for pressure oscillations, flow separation and reattachment. In solid rockets flow reattachment will favour secondary ignition and that will add to the complexity of the starting transient prediction.

• Advances in concrete construction
• /
• 제11권4호
• /
• pp.323-333
• /
• 2021

The main objective of this study is to characterize and evaluate the hydrophobic performance of polymer-based water-repellent coatings on cementitious mortar surfaces. Different concentrations of poly(vinyl acetate) (PVAc) and poly(1,4-butylene adipate) (PBA) were prepared in the laboratory and their applicability and performance was tested experimentally by water absorption test and analysis of surface contact angles of cementitious mortar specimens. According to the results of this study, it can be stated that incorporation of nano polymer particles on the surface of cementitious mortar specimens can enhance contact angles and reduce water absorption by increasing hydrophobicity. However, a dosage limit exists for polymer materials in coating, and observed hydrophobic improvements decreases when polymer dosage reached beyond the limit. Additionally, it is observed that water absorption of polymer coated cementitious mortars is closely related with the results of surface contact angle.