1.5 Tesla 기기에서 중심주파수 조정과 송 신호강도(Transmission Gain)값 변화에 따른 인공물이 있는 자기공명영상의 질 보상에 관한 연구

이재승,구은회,박철수,이선엽,이한주,Lee, Jae-Seung,Goo, Eun-Hoe,Park, Cheol-Soo,Lee, Sun-Yeob,Lee, Han-Joo 한국의학물리학회 2009 의학물리 Vol.20 No.4

자화율(susceptibility) 및 강자성체(ferromagnetic body)에 의한 인공물(artifact) 영향을 줄이기 위하여 중심주파수(center frequency) 정렬과 송 신호강도(transmission gain)값의 변화로 영상의 질을 보상하고자 한다. 본원에 내원한 환자 중 총 30명에 대하여 두 경부(head and neck)질환을 의심한 환자 중 남자 15명, 여자 15명으로 평균나이는 45세이었다. 사용된 장비는 GE 1.5T unit (GE, General Electric medical system, High Density)를 사용하여 Transmission gain (TG) 값을 평균 몸무게 60 kg을 기준으로 70, 90, 110, 130, 150까지 변환하여 검사를 하였다(p<0.05). 본 연구의 결과로서, 조영제 주입 전과 후의 지방소거 결과는 TG (70, 90, 110, 130, $150=3.23{\pm}0.35$, $4.31{\pm}0.02$, $4.23{\pm}0.21$, $5.12{\pm}0.25$, $7.13{\pm}0.72$, $8.31{\pm}0.01$, $5.21{\pm}0.15$, $6.14{\pm}0.08$, $5.23{\pm}0.72$, $5.91{\pm}0.06$)값에 다른 점수 분포를 나타났다(p<0.05). 절대값 대조도대 잡음비는 (TG, CNRpre, CNRpost, 70: $-1.44{\pm}0.11$, $-2.7{\pm}0.04$, 90: $-2.18{\pm}0.42$, $-4.41{\pm}0.43$, 110: $-2.89{\pm}0.43$, $-5.23{\pm}0.02$, 130: $-2.34{\pm}0.05$, $-5.26{\pm}0.01$, 150: $-2.09{\pm}0.08$, $-3.87{\pm}0.12$)을 얻었다(p<0.05). 본 실험에서 중심주파수 조정과 송 신호강도(transmission gain)값의 변화에 따라 인공물이 있을 때 영상의 질을 보상할 수 있다는 것을 확인하였다. The purpose of this study is to compensate for susceptibility and a ferromagnetic body artifact using CFA and TGV on MR Imaging. A total of 30 patients (15 men and 15 women, mean age: 45 years) were performed on head and neck diseases. MR Unit used a 1.5T superconducting magnet (GE medical system, High Density). This study have investigated by changing with CFA and TGV (70, 90, 110, 130, 150) searching for compensation values about susceptibility and a ferromagnetic body artifact in 60 kg standards of body weight (p<0.05). As a quality results, Image qualities were obtained at different score from CFA and TGV (70, 90, 110, 130, $150=3.23{\pm}0.35$, $4.31{\pm}0.02$ $4.23{\pm}0.21$, $5.12{\pm}0.25$, $7.13{\pm}0.72$, $8.31{\pm}0.01$, $5.21{\pm}0.15$, $6.14{\pm}0.08$, $5.23{\pm}0.72$, $5.91{\pm}0.06$, p<0.05). Absolute CNRs (TG, CNRpre, CNRpost) were acquired with (70:$-1.44{\pm}0.11$, $-2.7{\pm}0.04$, 90:$-2.18{\pm}0.42$, $-4.41{\pm}0.43$, 110:$-2.89{\pm}0.43$, $-5.23{\pm}0.02$, 130:$-2.34{\pm}0.05$, $-5.26{\pm}0.01$, 150: $-2.09{\pm}0.08$, $-3.87{\pm}0.12$, p<0.05). In conclusions, this study could be compensated for metal and flow artifacts surrounding the tissues having artifact by changing CFA and TGV.

Synthesis and Characterization of the Mixed-valence $[Fe^{II}Fe^{III}BPLNP(OAc)_2](BPh_4)_2$ Complex As a Model for the Reduced Form of the Purple Acid Phosphatase

이재승,이호진,이강봉,허남회,Lee, Jae Seung,Jung, Dong J.,Lee, Ho Jin,Lee, Gang Bong,Heo, Nam Hoe,Jang, Ho G. Korean Chemical Society 2000 Bulletin of the Korean Chemical Society Vol.21 No.10

[Fe II Fe III $BPLNP(OAc)_2](BPh_4)_2$ (1), a new model for the reduced form of the purple acid phosphatases, has been synthesized by using a dinucleating ligand, 2,6-bis[((2-pyridylmethyl)(6-methyl-2-pyridylmethyl)ami-no)methyl]-4-nitrophenol (HBPLNP) . Complex 1 has been studied by electronic spectral, NMR, EPR, SQUID, and electrochemical methods. Complex 1 exhibits two strong bands at 498 nm $(\varepsilon=$ 2.6 ${\times}10^3M-^1cm-^1)$ and 1363 nm $(\varepsilon=$ 5.7 ${\times}10^2M-^1cm-^1)$ in $CH_3CN.$ These are assigned to phenolate-to-FeIII and intervalence charge-transfer transitions, respectively. NMR spectrum of complex 1 exhibits sharp isotropically shifted resonances, which number is half of those expected for a valence-trapped species, indicating that electron transfer between FeⅡ and FeⅢ centers is faster than NMR time scale at room temperature. Complex 1 undergoes quasireversible one-electron redox processes. The $FeIII_2/FeIIFeIII$ and $FeIIFeIII/FeII_2$ redox couples are at 0.807 and 0.167 V ver-sus SCE, respectively. It has Kcomp = 5.9 ${\times}$10 1s(acetato) ligand combination sta-bilizes a mixed-valence FeIIFeIII complex in the air. Interestingly, complex 1 exhibits intense EPR signals at g = 8.56, 5.45, 4.30 corresponding to mononuclear high-spin FeⅢ species, which suggest a very weak magnetic coupling between the iron centers. Magnetic susceptibility study shows that there is a very weak antiferromag-netic coupling (J = $-0.78cm-^1$, H = $-2JS_1${\times}$S_2)$ between FeII and FeIII centers. Thus, we can suggest that complex 1 has a very weak antiferromagnetic coupling between the iron centers due to the electronic effect of the nitro group in the bridging phenolate ligand.

식민주의와 법학

이재승 ( Jae seung Lee ) 민주주의법학연구회 2011 민주법학 Vol.0 No.45

This article aims at reviewing colonialist legal ideologies and tackle critically methodological problems raised by legal historians concerning research of the Japanese colonial legal system. The modern international law justified the colonization of non-european worlds by the western Europe under the name of civilizing mission. The Japanese imperialism colonized Korea after its rapid industrialization. The Japanese Empire constructed the capitalist, authoritarian regime in Korea. Colonialist legal ideologies have had continuous bad influences upon the mentality of the Koreans, though the Korean Government had transformed widely the colonial enactments since 1948. Prof. Dr. Chulwoo Lee proposes an alternative quantitative conception of modernity against the normative essentialist one, intending to make a detour around the recent controversy between the colonial exploitation theory and colonial modernization theory. But his proposal does not seem to approach properly the normative view of modernity, because modernity in essence implies a holistic project which aspires to realize the normative ideal of civil society. The terms like ``colonial modernity`` or ``colonial modern law`` are seemingly paradoxical or ambiguous, but very useful to explain the characteristic features of the modern legal history in Korea. Prof. Lee also proposes to introduce the microscopic historical method for catching the legal interplays or games between ordinary people and colonial authority and to understand diversification of forms of colonial domination instead of a naive instrumentalist view of law. But Lee`s methodological proposal lacks in the appropriate structuralist perspective for analyzing colonial oppressive politico-legal structure. Alternatively, this essay reviews the application of Fraenkel`s Dual State Thesis to the Japanese colonial legal system. His theory which originally intended to explain the National-socialist political regime simultaneously offers a good perspective for the Japanese colonial legal system, but with some appropriate modifications.

¹⁸F-FDG PET-CT 검사에서 췌장암, 췌장염, 정상 췌장에 대한 최대 표준섭취계수의 임상적 기준 설정

이재승,권대철,Lee, Jae-Seung,Kweon, Dae Cheol 대한의용생체공학회 2018 의공학회지 Vol.39 No.2

The aim of this study were to establish the clinical references and guidelines for the maximum standardized uptake ($SUV_{max}$) value of pancreatic cancer, pancreatitis, and normal pancreas in $^{18}F-FDG$ PET-CT examinations for pancreatic disease. For this purpose, we performed the statistical analysis on the descriptive statistics, percentiles and inter quartiles range (IQR), normal distribution, and using the probability density function for pancreatic cancer, pancreatitis, and normal pancreas. As a result, the clinical reference of $SUV_{max}$ for the pancreatic cancer, pancreatitis, and normal pancreas was more than 3.45, 1.91 to 2.62, and less than 1.91, respectively. Also, optimal cut-off value for applying the dual time point PET-CT examination was determined to be 2.62. The results of this study are summarized as follows: first, we suggests the clinical reference and guideline for the pancreatic cancer, pancreatitis, and normal pancreas, and second, suggests a scientific approach to improve diagnostic accuracy of pancreatic disease by deviating from an approximate experience approach.

재생 굵은골재와 제강슬래그 잔골재를 사용한 재생 콘크리트의 특성에 관한 실험적 연구

이재승,나옥빈,Lee, Jaesung,Na, Okpin 한국자원리싸이클링학회 2015 資源 리싸이클링 Vol.24 No.5

본 연구는 재생 굵은골재와 산업부산물인 급냉 제강슬래그 잔골재를 이용한 친환경 재생 콘크리트의 재료적 특성을 파악하고 적정 혼합비를 도출하는데 그 목적이 있다. 이를 위해서 재생 굵은골재의 치환율은 30%에서 50%까지 증가시켰으며, 급냉 제강슬래그 잔골재는 10%에서 50%까지 증가시켜서 물성실험을 수행하였다. 그 결과, 재생골재의 치환율이 증가함에 따라 강도가 감소하였으나 급냉 제강슬래그 잔골재의 혼입율을 증가함에 따라 강도가 증가됨을 알 수 있었다. 더불어 급냉 제강슬래그 잔골재의 적정 치환율은 압축강도 및 탄성계수 등을 고려했을때 20~30%로 판단되며, 재생 굵은골재의 치환율 증가에도 도움이 될 것으로 사료된다. The purpose of this study is to investigate the optimum replacement rate and material properties of eco-friendly recycled concrete using recycled coarse aggregates and rapid-chilled steel slag fine aggregates. The replacement rate of recycled coarse aggregates was increased from 30% to 50% of total volume of coarse aggregates and the rapid-chilled steel slag aggregates were substituted for 10% to 50% of total volume of fine aggregates. As a result, the increment of recycled coarse aggregates in concrete caused the reduction of the compressive strength. On the other hand, as increasing the replacement ratio of rapid chilled steel slag aggregates, the compressive strength was enhanced. Furthermore, the optimum use of rapid chilled steel slag aggregates was suggested up to 20~30% of fine aggregates and the use of it could be helpful to expand the replacement rate of recycled aggregates.

DQ: Two approaches to measure the degree of decentralization of blockchain

이재승,Byungheon Lee,Jaeyoung Jung,심호준,김황남 한국통신학회 2021 ICT Express Vol.7 No.3

Blockchain technology innovatively removes the need for intermediaries and establishes a trust-less trust system by peer-to-peer networks and distributed ledger technology. It is still difficult to clarify the specific degree of decentralization of blockchain even though the decentralized characteristic of the system is derived from this system structure. Namely, the criteria for determining whether decentralized are not well established and do not reflect the real world well. So we propose two approaches to measure the degree of decentralization of blockchain system that currently exists: Censorship resistance and geographical diversity. This paper outlines the meaning of each decentralization quotient and explains how those indexes can be applied in respect of the user protection.

열간단조된 $\gamma$-TiAl 합금의 이방성에 관한 연구

이재승,박노진,김성진,김승언,오명훈,Lee, Jae-Seung,Park, No-Jin,Kim, Seong-Jin,Kim, Seung-Eon,O, Myeong-Hun 한국재료학회 2000 한국재료학회지 Vol.10 No.9

본 논문에서는 Ti-48.5at%Al-0.96at%Mo 조성을 갖는 $\gamma$-TiAl 합금은 항온 단조 및 후속 조직제어 열처리 시 발달하는 집합조직의 변화에 관해 연구하였다. 특히, 동적 재결정 후 조직제어 열처리 온도와 시간의 증가에 따라 발생하는 lamellar volume fraction 과 집합조직 변화에 주목하여 관찰하였다. 동적 재결정 후 집합조직은 ND$\perp${302) 선분과, TD$\perp${100) 및 이에 비해 상대적으로 다소 약한{111) 성분들이 발달하였으며, 열처리 온도와 시간이 증가함에 따라 lameller volume fraction 은 증가했고 동일한 성분의 집합조직도 점차 강하게 발달함을 알 수 있었다. 하지만 상온인장시험 결과는 lameller volume fraction이 증가할수록 낮은 상온 연신을 보였는데, 이는 준 층상조직을 갖는 $\gamma$-TiAl합금의 상온인장특성이 집합조직의 영향보다는 lameller volume fractio과 같은 미세조직 특성에 더욱 강하게 영향을 받기 때문인 것으로 판단된다. The texture evolution during isothermal forging and subsequent heat treatment in Ti-48.5at%Al-0.6at%Mo alloy was investigated. Especially, in the present study, research interest was focused on the interrelation between lamellar volume fraction and textures varied with the change of heat-treated time and temperature. It was found that texture components having ND┴{302) and TD$\perp${100} with minor TD$\perp${111} were developed by isothermal forging. In addition, when the followed heat-treatment time and temperature increased from $1330^{\circ}C$/10h to $1350^{\circ}C$/20h respectively, both the lamellar volume fraction and the intensity of textures mentioned above also gradually increased. However, the tensile elongation at room temperature decreased oppositely, as the lamellar volume fraction increased. These results suggested that tensile properties of $\gamma$-TiAl with the nearly lamellar microstructure at room temperature were affected more strongly by the microstructural features such as lamellar volume fraction rather than by textures.

개방형 5G 프론트홀 기술 동향

이재승,박재우,이문식,Lee, J.S.,Park, J.W.,Lee, M.S. 한국전자통신연구원 2022 전자통신동향분석 Vol.37 No.3

Traditional centralized radio access network architecture used for 4G is based on Option 8, a functional split between PHY and RF. This option is commonly used with a fronthaul interface based on common public radio interface (CPRI) specifications; however, the increased data rates in 5G make this option impractical because of the fronthaul interface's high bandwidth requirement. Since CPRI specifications have many vendor-specific options, achieving multi-vendor interoperability becomes challenging. Open RAN (O-RAN) Alliance is developing novel open fronthaul interface specifications based on the functional split Option 7-2x, one of the intra-PHY split options, to relax the bandwidth requirement of the fronthaul interface and achieve multi-vendor interoperability. This article provides a brief overview of the various functional split options for 5G fronthaul that have been reported so far and existing fronthaul technologies. Further, the technological trends in the 5G open fronthaul interface is discussed, focusing on the O-RAN Alliance specifications under standardization.

단크론 항체를 이용한 나환자 말초 혈액 림프구 아형의 Flow Cytometry에 의한 분석

이재승,박석돈,정헌택,장선일,문형배,정구원,김도일 ( Jae Seung Lee,Seok Don Park,Hun Taeg Chung,Seon Il Jang,Hyung Bae Moon,Koo Weon Jeong,Do Il Kim ) 대한피부과학회 1992 대한피부과학회지 Vol.30 No.4

남.북한 문학 분야의 쟁점들-순수과학을 중시하는 북한의 학풍

이재승,Lee, Jae-Seung 대한출판문화협회 1998 출판저널 Vol.245 No.-

분단 이후 반세기 세월이 흐르는 동안 과학기술 분야에도 이질적인 문제가 산재해 있다. 남한이 응용과학을 토대로 삼고 있는데 비해 북한은 순수과학을 중시한다는 점, 북한이 발표했던 연구실적에 대한 진위 여부, 북한 과학자들과의 처우 문제 등은 통일 이후 논란이 될 수 있는 부분이다. 그러나 이런 예상되는 쟁점은 인문.사회과학 분야에 비하면 거의 없는 것이라 해도 과언이 아니다.