http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Sehyun Shin,Myung-Su Park,Yunhee Ku,Joo-Hee Jang,Jang-Soo Shu 대한기계학회 2005 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.19 No.1
Aggregation of red blood cells (RBCs) is a major determinant of blood viscosity. There have not been available techniques for measuring RBC aggregation and viscosity, simultaneously. A laser transmission technique has been combined with a slit rheometry, which shows significant advances in rheometer design, operation and data analysis. A laser beam traverses a blood suspension flowing through a slit and is scattered by RBCs in the volume. The transmitted light is captured by a photodiode, linked to a computer, while the differential pressure variation is measured by a pressure transducer. Both measurements of the laser-transmitted intensity and pressure with respect to time enable to determine the aggregation index and the viscosity. The advantages of this design are in its simplicity, i.e., ease of operation and no moving parts, low cost and a short operating time. In addition, the slit-flow aggregometer can be easily used in a clinical setting owing to the incorporation of a disposable element that holds the blood sample.
Optical Detection of Red Blood Cell Aggregation in a Disposable Microfluidic Channel
Sehyun Shin,Ju-Hee Jang,Myung-Soo Park,Yunhee Ku,Jang-Soo Suh 대한기계학회 2005 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.19 No.3
The aggregability if led blood cells (RBCs) was determined by laser backscattering light analysis in a microfluidic channel Available techniques for RBC aggregation often adopt a rotational Couette-flow using a bob-and-cup system for disaggregating RBCs, which causes the system to be complex and expensive. A disposable microfluidic channel and vibration generating mechanism were used in the proposed new detection system for RBC aggregation Prior to measurement, RBC aggregates in a blood sample were completely disaggregated by the application of Vibration-induced shear With the present apparatus, the aggregation indexes of RBCs can be measured easily with small quantities of a blood sample The measurements with the present aggregometer were compared with those of LORC A and the results showed a strong correlation between them The aggregability of the defibrinogenated blood RBCs is markedly lower than that of the normal RBCs The noble feature of this design is the vibration-induced disaggregation mechanism, which can incorporate the disposable element that holds the blood sample.
Optical Detection of Red Blood Cell Aggregation in a Disposable Microfluidic Channel
Shin Sehyun,Jang Ju-Hee,Park Myung-Soo,Ku Yunhee,Suh Jang-Soo The Korean Society of Mechanical Engineers 2005 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.19 No.3
The aggregability of red blood cells (RBCs) was determined by laser backscattering light analysis in a microfluidic channel. Available techniques for RBC aggregation often adopt a rotational Couette-flow using a bob-and-cup system for disaggregating RBCs, which causes the system to be complex and expensive. A disposable microfluidic channel and vibration generating mechanism were used in the proposed new detection system for RBC aggregation. Prior to measurement, RBC aggregates in a blood sample were completely disaggregated by the application of vibration-induced shear. With the present apparatus, the aggregation indexes of RBCs can be measured easily with small quantities of a blood sample. The measurements with the present aggregometer were compared with those of LORCA and the results showed a strong correlation between them. The aggregability of the defibrinogenated blood RBCs is markedly lower than that of the normal RBCs. The noble feature of this design is the vibration-induced disaggregation mechanism, which can incorporate the disposable element that holds the blood sample.
Ultrasensitive Detection of Single-Walled Carbon Nanotubes Using Surface Plasmon Resonance
Jang, Daeho,Na, Wonhwi,Kang, Minwook,Kim, Namjoon,Shin, Sehyun American Chemical Society 2016 ANALYTICAL CHEMISTRY - Vol.88 No.1
<P>Because single-walled carbon nanotubes (SWNTs) are known to be a potentially dangerous material, inducing cancers and other diseases, any possible leakage of SWNTs through an aquatic medium such as drinking water will result in a major public threat. To solve this problem, for the present study, a highly sensitive, quantitative detection method of SWNTs in an aqueous solution was developed using surface plasmon resonance (SPR) spectroscopy. For a highly sensitive and specific detection, a strong affinity conjugation with biotin streptavidin was adopted on an SPR sensing mechanism. During the pretreatment process, the SWNT surface was functionalized and hydrophilized using a thymine-chain based biotinylated single-strand DNA linker (B-ssDNA) and bovine serum albumin (BSA). The pretreated SWNTs were captured on a sensing film, the surface of which was immobilized with streptavidin on biotinylated gold film. The captured SWNTs were measured in real-time using SPR spectroscopy. Specific binding with SWNTs was verified through several validation experiments. The present method using an SPR sensor is capable of detecting SWNTs of as low as 100 fg/mL, which is the lowest level reported thus far for carbon-nanotube detection. In addition, the SPR sensor showed a linear characteristic within the range of 100 pg/mL to 200 ng/mL. These findings imply that the present SPR sensing method can detect an extremely low level of SWNTs in an aquatic environment with high sensitivity and high specificity, and thus any potential leakage of SWNTs into an aquatic environment can be precisely monitored within a couple of hours.</P>
The Effect of Vibration on the Hemorheologicai Characteristics of Non-aggregated Blood
Sehyun Shin,Yun-Hee Ku,Su-Yeon Moon,Jang-Soo Suh 대한기계학회 2003 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.17 No.7
The present study investigates the hemorheological characteristics of blood flow with applying vibration to a non-aggregating red blood cell suspension. In order to obtain the non-aggre-gating RBC suspension, blood samples were treated with vibration at a specified condition, which viscosities were taken before and after the treatment, respectively. The viscosity of the blood samples after treatment was higher than before treatment. These treated blood samples were forced to flow through a capillary tube that was vibrated perpendicularly to the direction of the flow. The experimental results showed that vibration caused a reduction of the flow resistance of the non-aggregated blood. The reduction of the flow resistance was strongly dependent on both frequency and amplitude of vibration. These results show potential in treating various diseases in the microcirculation associated with blood cell aggregation.
Deformability of Red Blood Cells : A Determinant of Blood Viscosity
Sehyun Shin,Yunhee Ku,Myung-Su Park,Jang-Soo Suh 대한기계학회 2005 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.19 No.1
The suspension of hardened red blood cells (RBCs) differs from the suspension of normal RBCs with respect to their rheological behavior. The present study investigated the effect of deformability of RBCs on blood viscosity. RBC deformability and blood viscosity were measured with a recently developed slit-flow laser-diffractometer and the pressure-scanning capillary viscometer, respectively. At the same level of cell concentration, the viscosity of the hardened RBC suspension is higher than that of the normal RBCs suspension. An increase in cell percentage for hardened RBCs shows the significant increase in the level of blood viscosity compared to the normal RBCs. In addition, it was found that RBC deformability played an important role in reducing viscosity at low shear rates as well as high shear rates. These results present the evidence for the effect of RBC deformability on blood viscosity using newly developed methods, which can be used in early diagnosis of the cardiovascular diseases.
A Study on Repowering of Domestic Aged Coal-fired Power Plant
Baek, SeHyun,Kim, YoungJoo,Kim, HyunHee,Park, SangBin,Jang, JiHoon Korea Electric Power Corporation 2017 KEPCO Journal on electric power and energy Vol.3 No.1
Recently, the public opinion is growing that the main cause of greenhouse gas, fine dust and nitrogen oxide, sulfuric acid emission is coal-fired power plant, and now the decommission or conversion to other clean fuel is being demanded. However, it is a huge national loss to decommission coal-fired power plant with remaining life, and also simple fuel converting to natural gas will lead to drastic rise on power generating cost. Therefore, this study aims to provide the analysis result about the reduction effect of $CO_2$, environment emission, and to influence to power plant performance and facilities when repowering with adding gas turbine is applied to domestic aged coal-fired power plant.
발전용 보일러에 대한 다중영역분할 화로해석 기법의 활용성 연구
Baek, SeHyun,kim, Donggyu,Lee, Jang Ho 한국전력공사 2020 KEPCO Journal on electric power and energy Vol.6 No.4
본 연구에서는 화력 발전소 보일러에 대한 연소 및 열전달 해석을 위하여 화로 내부를 다중영역으로 나누고 각 영역에서 energy와 mass balance는 1차원으로 계산하고, 복사열전달은 3차원으로 계산하는 다중영역분할 화로해석 기법을 활용하였다. 그리고 적용 기법에 대한 신뢰성 검증을 위하여 국내 500 MW 급 석탄화력 보일러 화로에 대한 계산 값과 보일러 제작사의 설계 데이터를 비교하여 양호함을 확인하였고, 동일한 설비에 대한 CFD 해석과 비교한 결과 유사한 경향을 얻었다. 본 계산 기법은 CFD 화로해석 보다는 덜 상세하지만, 빠른 시간에 연료반응성, 화로형상 및 운전변수에 따른 특성을 계산할 수 있는 장점이 있으므로 발전소 현장에서의 설비감시진단 및 일일 연료/운전 계획 수립 등 활용성 측면에서 유용할 것으로 예상된다. In this study, a multi-zone furnace analysis method that couples a 1D energy and mass balance calculation with a 3D radiative heat transfer calculation is tested in order to verify its reliability. The calculated results for a domestic 500 MW capacity coal-fired boiler furnace were compared with the design data of the boiler manufacturer and CFD analysis, and a good agreement was achieved. Although this calculation method is less sophisticated than the CFD furnace analysis, it has an advantage in terms of calculation time while being able to provide the furnace behavior according to the fuel characteristics and operational variable changes. Therefore, it is expected to be useful for boiler operation diagnosis and daily fuel/operation planning.