Entanglement Changes under Various Spin-Environment Models

최태승,이혁재 한국물리학회 2008 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.53 No.4

We have studied the effects of various environments on the degree of entanglement of a two- qubit system with no direct interaction. The interaction between the system and the environment is considered as a two-spin interaction. We have focused on the case in which each system qubit interacts with different environment qubits so that indirect interactions are not involved. The results show that the two-qubit system with no initial entanglement that has no direct interaction can be entangled only under interactions with entangled elements in a common bath. This implies that an entanglement of the environment can be transferred to an entanglement of a two-qubit system that has no direct and indirect interactions.

Newton-Wigner Position Operator and the Corresponding Spin Operator in Relativistic Quantum Mechanics

최태승 한국물리학회 2015 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.66 No.6

A relativistic spin operator is the difference between the total and the orbital angular momentum. As the unique position operator for a localized state, the remarkable Newton-Wigner positionoperator, which has all the desirable commutation relations of a position operator, can give a properspin operator. Historically, the three important spin operators proposed by Bogolubov et al., Pryce,and Foldy-Woutheysen, respectively were investigated to manifest a spin operator corresponding tothe Newton-Wigner position operator. We clarify a unique spin operator in relativistic quantummechanics, which can be described by using the Dirac Hamiltonian.

Relativistic Spin Operator and Lorentz Transformation of the Spin State of a Massive Dirac Particle

최태승,Hoppe Jens Reimar 한국물리학회 2013 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.62 No.8

We have shown that the covariant relativistic spin operator is equivalent to the spin operator commuting with the free Dirac Hamiltonian. This implies that the covariant relativistic spin operator is a good quantum observable. The covariant relativistic spin operator has a pure quantum contribution that does not exist in the classical covariant spin operator. Based on this equivalence, reduced spin states can be clearly defined. We have shown that depending on the relative motion of an observer, the change in the entropy of a reduced spin density matrix sweeps through the whole range.

본태성 복합 한냉글로불린혈증 1 예

최태승,권영주,조원용,김형규 대한신장학회 1988 학술대회및초록집 Vol.7 No.1

오프셋 스트립 휜 열교환기의 압력강하 특성 분석과 상관식 개발

최태승(Tae seung Choi),최준호(Junho Choi),김택근(Taek keun Kim) 한국유체기계학회 2023 한국유체기계학회 학술대회 논문집 Vol.2023 No.7

지속적 외래 복막 투석이 당뇨성 신부전 환자의 β2-Microglobulin 에 미치는 영향

최태승(Tae Seung Choe),김선숙(Sun Sook Kim),권영주(Young Joo Kwon),조원용(Won Yong Cho),김형규(Hyoung Kyu Kim),원동준(Dong Joon Woo) 대한내과학회 1991 대한내과학회지 Vol.41 No.3

N/A To evaluate the effect of CAPD on the removal of beta-2-microglobulin (B2MG) in the patients with diabetic renal failure, serum levels and clearances of creatinine, urea, and B2MG, ultrafiltration rates, mass transfer raters of B2MG, and equilibration curves were determined in 5 diabetics and 5 nondiabetics with chronic renal failure undergoing CAPD. The study was carried out using peritoneal dialysis solutions with 1.5% dextrose for 240minutes of dwell time. The valuse of plasma were the means of 2samples taken at the start and after 240minutes. The values of peritoneal dialysis solution were determined on 3mlsamples taken at the 30minutes, 60minutes, 120minutes, and 240minutes after dialysate infusion. The authors results are as follows; 1) The serum R2MG levels were 39.4mg/1 in nondiabetic and 18.2mg/1 in diabetic renal failure groups which were significantly higher values than normal values and significantly lower values than that of hemodialyzed patients. 2) The peritoneal clearances of B2MG were 0.64 ml/ min in nondiabetic and 0.90ml/min in diabetic renal failure groups which represented 7.7% and 11.0% of dialysate flow rate in each groups. In diabetic renal failure group, patient 'age and mass transfer rate of B2MG were positively correlated with the peritoneal clearance of BRMG (r=0.25 and 0.76). 3) The equilibration curves of creatinine and urea were well fitted to their standard equilibration curves in both groups. In diabetic renal failure group, the dialysate to plasma ratios of creatinine and urea showed the linear correlation with the in-dwelling time during the 240minutes of dwell time (r=0.9964 and 0.9742) 4) The equilibration curves of B2MG showed that the D/P ratios of the diabetic group were constantly higher than those of nondiabetic group. The equilibration slopes between 120minutes and 240minutes after indwelling were significantly lower than those between the start and 120minutes after dwelling in each nondiabetic and diabetic groups. In conclusin, the standard CAPD may allow a constant B2MG removal diabetic renal failure patients by the means of diffusion and increased peritoneal vascular permeability of B2MG.

다구찌법을 이용한 환형 휜 형태의 3D프린터 heatsink의 Nusselt number 계산을 위한 CFD 격자에 대한 연구

최형인,최태승,김택근 한국기계기술학회 2024 한국기계기술학회지 Vol.26 No.2

Research has been conducted on a wide variety of 3D printer circular fin heads. In this study, we proposed a sequence and method for a more efficient mesh study in the CFD model to calculate the Nusselt number of the circular fin head of an FDM 3D printer using the Taguchi method, sensitivity, and ANOVA. As a result, the CFD model to calculate the Nusselt number of the circular fin head of an FDM 3D printer has high sensitivity and contribution in the order of Base target mesh size, Prism layer number, and Prism layer thickness. We propose to increase work efficiency by performing mesh optimization in the order of factors with high sensitivity to level changes.

만성 수은중독의 임상적 고찰

위경소,최태승,이석준,조원용,김형규,최원충 대한내과학회 1990 대한내과학회지 Vol.38 No.1

Nowadays, the incidence of heavy metal posisoning is increasing, especially in developing countries. The authours experienced and managed 6 patients highly suspected of chronic mercury poisoing. These patients were workers in a small electric lamp company, ballooning the lamps by mouth. They inhaled mercury vapor during their work. The authours evaluated these patients by EMG, MMPI, kidney and liver needle biopsy and measured the blood and urine mercury concentration by atomic absorption spectrophotometry. The results are as follows: 1) The mean duration of exposure to mercury was 40. 8±35.0 months and the mean duration of symptom and signs was 13.0±4.2 months. 2) The main symptoms of these patients were headache(5/6), generalized weakness(4/6) and tremor(2/6). 3) On routine laboratory evaluatioin including MMPI and EMG, we couldn't find any specific abnormal finding. 4) In liver biopsy, diffuse hepatocyte swelling and sinusoidal dilatations was found in 5 patients. In the EM finding of kidney biopsy, dark-black-round pigments of the lysosomes of the proximal tubular epithelial cells are found in 2 patients. 5) After chelation therapy, the blood mercury decreased and urinary excretion of mercury increased, esplcially in 2 patients who excrete little amounts of mercury before chelation therapy.

한국형 출혈열 환자에서 혈장 Catecholamine의 변화

정동국,최태승,김용섭,류승관,조원용,김형규,원동준 대한내과학회 1990 대한내과학회지 Vol.38 No.1

To evaluate the relationship between plasma catecholamines and the pathogenesis of acute renal failure(AFR), the plasma NE, E, Dopamine, DOPA and DOPAC were measured in 13 cases of Korean hemorrhagic fever(KHF) with renal failure and 12 normal persons as a control group by HPLC with ECD. To correlate these values with other renal functions, the blood pressure(systolic and diastolic), pulse rate, serum creatinine and creatinine clearance were measured. The results were failure as follows: 1) In 13 cases of KHF with renal failure, the plasma NE was increased in the oliguric and diuretic phases compared with the control group(p<0.05). The plasma E was also increased in the diuretic phase(p<0.05). 2) In the follow-up 7 cases, plasma E and NE were decreased in the diuretic phase(p<0.05). 3) The plasma E had a positive correlation with plasma Cr in the oliguric phase and a negative correlation with plasma Cr in the diuretic phase. The plasma NE had a positive correlation with plasma Cr in the diuretic phase. From these results, the increased synthesis of catecholamines is considered to be one of the pathogenic factors in KHF with acute renal failure. And the renal response to changes of catecholamines may be different with each phase in Korean hemorrhagic fever.

가계 혼합의 작동원리 - 시뮬레이션

김선명,김형순,최태승,복은 한국물리학회 2009 새물리 Vol.59 No.5

We used the Monte Carlo method to investigate the mechanism of family mixing, which we had previously studied analytically. Some postulates imposed in the previous study were modified in this Monte Carlo study to reflect more realistic situations. In this study, we kept the personal vectors in the program and then calculated the averaged-family vectors from them. Under the given postulate the asymptotic vector of the averaged family-vectors was no longer parallel to the sum of the initial (zeroth generational) family vectors, in contrast to the previous study, due to the unmarried people in families. According to the simulation, in the three-family model the asymptotic family-vector is positioned at the center of the oval-shaped normal distribution of the personal family-vectors. 기존에 해석적으로 연구하였던 가계혈통 혼합 과정을 Monte Carlo 방법을 이용하여 연구하였다. 보다 현실적인 상황을 반영하기 위하여 기존의 가정들은 이 Monte Carlo 방법에서 수정되었다. 이 연구에서는 특히 개인 벡터를 도입하여 평균적인 가계 벡터를 계산하였다. 평균 가계벡터의 asymptotic 행태는 기존의 연구 결과와는 달리 초기세대(0번째 세대) 가계 벡터들의 합과 더 이상 평행하지 않았으며 이는 변화된 가정에 따라 각 가계에서 결혼하지 못하는 사람들의 존재에 기인한다. 이 시뮬레이션에 따르면 3 가계 모델에서 개인 벡터들은 길쭉한 구면체 모양의 정규분포를 이루는데 asymptotic 가계 벡터는 이것의 중앙에 위치하였다.