http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 저자 : Seunghwan Bang (검색결과 16 건)
- 무료
- 기관 내 무료
- 유료
-
-
-
방승환(Seunghwan Bang),이현숙(Hyunsook Lee) 한국자기학회 2020 韓國磁氣學會誌 Vol.30 No.4
Imbalance of blood circulation caused by aggregation, rouleaux and morphological transform of red blood cell (RBC) influenced to cardiovascular diseases such as thrombosis, peripheral stenosis, and arteriosclerosis. This study intends to evaluate the effect of the pulsed magnetic field (PMF) on the aggregation and deformability of RBC. In hematocrit (HCT) 45% bloods diluted with phosphate buffered saline (PBS) and plasma, ESR rates were slowed by 1% and 6% after PMF stimulus of 2700 G, respectively. In addition, RBCs’ sedimentation rate after 12 hrs decreased to 25% at 2700 G, 28% at 1000 G, 32% at 400 G, compared to 34% at non-PMF group. After tBHP treatment in order to observe the RBC aggregation due to hemoglobin oxidation, the RBCs sedimentation proceeded rapidly, but progressed slowly after PMF stimulus. In RBC deformability experiment using filter having a size of 5 ㎛ smaller than the volume of RBC, the number of filtered RBCs increased by 2% at 400 G, 16% at 1000 G and 29% at 2700 G, compare with non-PMF group. For oxidative RBCs group, it also increased by more than 34% after PMF stimulus. Improvement of RBCs’ aggregation after PMF stimulus could be interpreted as the instantaneous rapid flux change of PMF affecting the zeta potential of RBCs. Also it is believed that PMF also affects the Ca<SUP>2+</SUP> ion pump which affects the hardening of RBCs’ membrane, thereby increasing the RBCs’ deformability. Therefore, the PMF stimulus could be used as a non-invasive treatment method for blood circulation disorder.
-
Estimation Model of Residual Water Evaporation During Vacuum Drying
Seunghwan Yu,Kyoung-sik Bang 한국방사성폐기물학회 2022 한국방사성폐기물학회 학술논문요약집 Vol.20 No.2
For the decommissioning or continuous long-term power generation of nuclear power plants, it is necessary to transfer the spent nuclear fuel from the wet storage pool to the dry storage. Spent nuclear fuel should go through the drying process, which is the first step of dry storage. The most important part in the drying process is the removal of the residual water. The spent fuel might be stored in a dry storage system for a long time. The integrity of internal components and spent fuel cladding should be maintained during the storage period. If residual water is present, problems such as aging of metal materials, oxidation of cladding, and the hydride-reorientation could occur. The presence or absence of residual water after vacuum drying is evaluated by pressure. If there is residual water in the vacuum drying process, it evaporates easily at low pressure to form water vapor pressure and the internal pressure rises. In the recent EPRI High burn up demonstration test, the gas inside the canister that satisfied the dryness criteria was extracted and analyzed. It showed that the water content was higher than the expected value. We are conducting verification studies on the pressure evaluation method, which is an indirect evaluation method of vacuum drying. The vacuum drying test was performed on small specimens at Sandia National Laboratory, and quantitative residual water evaluation was also performed. The report did not mention a detailed method for the assessment of residual water. Based on the test results of SNL, direct residual water evaluation was performed using energy balance. If the dryness criteria were satisfied, the quantitative amount of residual water was also evaluated. As a result, almost the same result as the evaluation result of SNL was derived, and it was confirmed that most of the water was removed when the dryness criteria was satisfied.
-
-
-
Bongjun Ji,Seunghwan Bang,Hyunseop Park,Hyunbo Cho,Kiwook Jung 대한산업공학회 2019 Industrial Engineeering & Management Systems Vol.18 No.3
Predictive maintenance is currently taking on new relevance. However, recent developments in predictive maintenancefocus on selecting the most appropriate algorithm based on the characteristics of a system and data given the criticalcomponents. Identifying the critical component has not been difficult because most predictive maintenance hasbeen applied to well-known critical components. However, as the cost of installation for predictive maintenance lowers,it may be desirable to apply predictive maintenance to machines where critical components have not yet beenidentified, especially machines in small- and medium-sized enterprises (SMEs). In this paper, an identification methodfor critical components for which predictive maintenance is appropriate is proposed using multi-criteria decision makingfor application to multi-component, complex machines. This paper proposes a decision-making process consideringthree different criteria: severity, occurrence, and detectability. The goal is to identify and prioritize critical componentsfor predictive maintenance. The technique for order performance by similarity to the ideal solution (TOPSIS)can take into account decision makers’ preferences. Sensitivity analysis is investigated and discussed. The proposeddecision-making approach allows a manufacturer to develop a customized introduction process for predictive maintenance
-
The Change of Capillaroscopic Features under Pulsed Magnetic Field
Kyunghun Shin,Seunghwan Bang,Hyoje Ahn,Hyunsook Lee 한국자기학회 2019 Journal of Magnetics Vol.24 No.1
The purpose of present study is to observe the change in capillaroscopic features before and after pulsed magnetic field (PMF) stimulus: the number, shape, length of capillary loop, and diameters of efferent capillary, and images of capillary loop. Nailfold capillary microscopy was used to quantitatively estimate the change of morphological characteristics of the capillaries. Capillary blood flow is recorded using video camera recorded at a frame rate of 60fps attached to the microscope. The velocities of capillary blood cell were 441 ± 22 and 508 ± 20 ㎛/s, before and after PMF stimulus, respectively. For the nailfold capillary morphologies, compared to before PMF, the more clearly visible loops are arranged as well as the capillary loop lengthened after PMF stimulus. Also the numbers of capillary loop/mm increased after PMF stimulus. In addition, tortuous capillary turned to hairpin shaped loop and the number of tortuous and abnormal capillaries are reduced after PMF stimulus. Our results proved the PMF stimulus on the palm of left hand for 10 min. provide the improvement of capillary blood flow, and it decreases vascular resistance in the blood micro-circulatory system. In addition, our study suggested quantitative and qualitative parameters of the nailfold vasculature in order to elucidate the effect of PMF. For expanding our findings, we need to have more subjects across a wide spectrum of age and with microvascular abnormalities, such as scleroderma, dermatomyositis and related disorders.
-
대용량 자료의 이항 분류에서의 충분 차원 축소를 위한 전향적 접근 방법
강종경(Jongkyeong Kang),박승환(Seunghwan Park),방성완(Sungwan Bang) 한국자료분석학회 2024 Journal of the Korean Data Analysis Society Vol.26 No.1
반응변수의 정보를 담고있는 설명변수의 저차원 부분공간인 차원축소공간을 찾는 충분 차원축소에 대한 연구는 주로 역방향 기반의 방법론에 근거하고 있다. 이러한 방법들은 구현이 용이한 장점이 있으나, 일반적으로 선형성 조건이나 상수 분산과 같은 제약 조건등을 필요로 한다. 이러한 한계를 극복하기 위해, 중심부분공간을 전향적으로 추정하는 기법들이 개발되었다. 특히, 재생성 커널 힐베르트 공간을 활용하는 방법들이 주목받았으나, 커널 공간의 특성으로 인해 대용량 자료의 분석에 직접적으로 활용하기에는 제한이 있다. 본 논문에서는 대용량 자료의 이항 분류에서의 충분 차원 축소를 위한 새로운 전향적 접근 방법에 관해 연구하였으며, 분할 정복기법을 활용하여 자료를 부분집합으로 나눈 다음 각 부분집합에서 독립적으로 차원 축소를 수행한 후 이를 종합하여 최종모델을 구축하는 방법을 제안하였다. 부분 자료의 분할 수가 적절히 선택되었을 때, 기존의 방법에 비해 예측 정확성에서 손실이 크지 않으면서도 저장공간 및 계산비용 측면에서 매우 효율적임을 입증하였다. 다양한 모형에서의 모의실험을 통해 다른 역방향기반의 방법들과 비교하여 예측 정확성 측면에서 뛰어남을 보였으며, 나아가 실제 자료의 분석을 통해 제안 방법의 유용성을 확인하였다. Sufficient dimension reduction, aimed at finding a lower-dimensional subspace in explanatory variables that contains response variable information, typically relies on inverse-based methodologies. These methods are easy to implement but often require linear or constant variance conditions. To address these limitations, techniques for forwardly estimating the central subspace have been developed. In particular, methods utilizing the Reproducing Kernel Hilbert Space have gained attention, but their use in analyzing large datasets is limited due to the characteristics of the kernel space. In this paper, we study a novel forward approach for sufficient dimension reduction in binomial classification of large-scale data. We propose a method that employs a divide-and-conquer technique to split data into subsets, then independently perform dimension reduction on each subset before synthesizing them into a final model. It was shown that when the number of partitions of data was appropriately selected, the loss in prediction accuracy was not significant compared to the existing method, while being efficient in terms of storage space and calculation cost. In addition, simulations in various models showed superior prediction accuracy than other inverse-based techniques. The utility of the proposed method was confirmed through the real data analysis.
-
KCI연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
