PET/CT 감쇠보정시 다양한 CT Kernel 적용에 따른 유용성 평가

이재영,성용준,윤석환,박찬록,이홍재,노경운,Lee, Jae-Young,Seong, Yong-Jun,Yoon, Seok-Hwan,Park, Chan-Rok,Lee, Hong-Jae,Noh, Kyung-Wun 대한핵의학기술학회 2017 핵의학 기술 Vol.21 No.2

PET/CT 영상 재구성시 감쇠보정맵을 사용하여 영상재구성에 적용한다. 감쇠보정 맵의 CT parameter을 변경하여 PET/CT 영상 재구성 할 때 적용하여 SUVmax에 어떤 영향을 미치는지 비교 평가해보고자 한다. 장비는 Biograph mCT 64를 사용하였고 Phantom은 NEMA IEC Body Phantom을 사용하였다. 실험을 위해 환자는 2017년 2월에서 3월까지 본원 PET/CT 검사를 시행한 환자 20명을 대상으로 Lung, Liver, Bone에 관심영역을 선택하여 기존 08f AC, 45f medium, 80f ultra sharp 방식의 CT kernel을 적용한 감쇠보정맵을 사용하여 PET/CT 영상 재구성에 도입 후 방사능 농도(kBq/mL), SUVmax, SD(standard deviation) 변화 유무를 평가하였다. Phantom 방사능 농도 측정 결과 B08f AC 대비 B45f 0.96%, B80f 6.58% 증가하였고 B08f AC 대비 B45f 0.86%, B80f 6.54%각각 증가하였고, SD의 경우 B08f AC 대비 B45f 1.27%, B80f 6.96% 증가하였다. 환자에서 부위별 SUV는 Lung에서 B08f AC 대비 B45f 1.6%, B80f 6.6%, Liver에서 B08f AC 대비 B45f 0.7%, B80f 4.7%, Bone에서 B08f AC 대비 B45f 1.3%, B80f 6.2% 증가를 보였다. 부위별 SD는 Lung에서 B08f AC 대비 B45f 6.2%, B80f 15.4%, Liver에서 B08f AC 대비 B45f 2.1%, B80f 11%, Bone에서 B08f AC 대비 B45f 를 사용할 때 2.3%, B80f 14.7% 증가를 보였다. CT Kernel변화에 따라 sharpness noise와 영상의 질은 변화를 보였으나 SUVmax와 SD는 통계적으로 유의한 차이가 없었다.(P>.05). 핵의학 영상은 정량적인 평가가 중요하다 따라서 부위에 따라 CT kernel이 적절하게 조절되고 noise level이 낮은 감쇠보정 맵을 사용하여 PET/CT 재구성시에 적용하여 정량적 평가에 오류를 줄이는 것이 중요하다고 사료되므로 따라서 같은 부위라 할지라도 sharpness noise가 인위적으로 증가된 kernel을 사용하는 것보다 noise가 낮은 kernel을 사용하는 것이 SD편차를 줄이고 정량적인 평가에 오류를 적게 하여 정확한 진단과 SUV 측정에 유용할 것으로 사료된다. Purpose Recently PET/CT image's attenuation correction is used CTAC(Computed Tomgraphy Attenuation Correction). it can quantitative evaluation by SUV(Standard Uptake Value). This study's purpose is to evaluate SUV and to find proper CT kernel using CTAC with applied various CT kernel to PET/CT construction. Materials and Methods Biograph mCT 64 was used for the equipment. We were performed on 20 patients who had examed at our hospital from february through March 2017. Using NEMA IEC Body Phantom, The data was reconstructed PET/CT images with CTAC appiled various CT kernel. ANOVA was used to evaluated the significant difference in the result. Results The result of measuring the radioactivity concentration of Phantom was B45F 96% and B80F 6.58% against B08F CT kernel, each respectively. the SUVmax increased to B45F 0.86% and B80F 6.54% against B08F CT kernel, In case of patient's parts data, the Lung SUVmax increased to B45F 1.6% and B80F 6.6%, Liver SUVmax increased to B45F 0.7% and B80F 4.7%, and Bone SUVmax increased to B45F 1.3% and B80F 6.2%, respectively. As for parts of patient's about Standard Deviation(SD), the Lung SD increased to B45F 4.2% and B80F 15.4%, Liver SD increased to B45F 2.1% and B80F 11%, and Bone SD increased to B45F 2.3% and B80F 14.7%, respectively. There was no significant difference discovered in three CT kernel (P >.05). Conclusion When using increased noise CT kernel for PET/CT reconstruction, It tends to change both SUVmax and SD in ROI(region of interest), Due to the increase the CT kernel number, Sharp noise increased in ROI. so SUVmax and SD were highly measured, but there was no statistically significant difference. Therefore Using CT kernel of low variation of SD occur less variation of SUV.

Interfacial Characteristics of Epoxy Composites Filled with γ-APS Treated Natural Zeolite

이재영,이상근,김상욱,Lee, Jae-Young,Lee, Sang-Keun,Kim, Sang-Wook 한국접착및계면학회 2001 접착 및 계면 Vol.2 No.3

${\gamma}$-APS (${\gamma}$-aminopropyltriethoxysilane)로 표면처리된 천연제올라이트와 에폭시 수지 복합 재료의 표면 자유 에너지, 인상강도 및 계면 모폴로지에 대해 연구하였다. 표면처리하지 천연제올라이트의 표면 자유에너지 성분 중에서 무극성 성분인 Lifshitz-van der Waals 성분, ${\gamma}{\frac{LW}{SV}}$는 $19.22mJ/m^2$이었고, 극성 성분인 Lewis acid-base 성분, ${\gamma}{\frac{AB}{SV}}$는 $15.27mJ/m^2$이 있다. ${\gamma}$-APS의 처리농도가 증가함에 따라 ${\gamma}{\frac{LW}{SV}}$값은 증가하였지만 ${\gamma}{\frac{AB}{SV}}$는 감소하였으며, 이는 ${\gamma}$-APS의 소수성 성분인 알킬기의 영향이 친수성 기인 아민이나 수산기의 영향보다 커지기 때문이다. 인장강도와 Young율은 ${\gamma}$-APS 처리에 의해 개선되었으며, SEM 분석에 의해 계면특성이 향상되었음을 확인하였다. Epoxy composites filled with natural zeolite was prepared to investigate the effects of silane coupling agent, ${\gamma}$-APS (${\gamma}$-aminopropyltriethoxysilane)on the surface free energy, tensile properties and interfacial morphology. The value of Lifshitz-van der Waals component, ${\gamma}{\frac{LW}{SV}}$ for polar was $19.22mJ/m^2$ and increased, while that of Lewis acid-base component, ${\gamma}{\frac{AB}{SV}}$ for polar was $15.27mJ/m^2$ and decreased with the increasing content of ${\gamma}$-APS treatment. It is due that the surface of the zeolite is more coated by hydrophobic of alkyl group than hydrophilic amine or hydroxyl group. The tensile strength and Young's modulus of epoxy system were improved by the treatment with ${\gamma}$-APS due to the strong interface bonding, which was confirmed by SEM.

연구논문 - 고분자공업분과 : Isoconversion 식에 의한 DGEBA / MDA / CTBN 계의 경화반응 속도론

이재영,심미자,김상욱 ( Jae Young Lee,Mi Ja Shim,Sang Wook Kim ) 한국공업화학회 1997 한국공업화학회 연구논문 초록집 Vol.1990 No.3

금속이온 교환 천연 제올라이트에 의한 o - Xylene 의 이성질화 반응

이재영,심미자,김상욱 ( Jae Young Lee,Mi Ja Shim,Sang Wook Kim ) 한국공업화학회 1995 공업화학 Vol.6 No.4

금속이온이 교환된 천연제올라이트에 의한 o-xylene의 이성질화 반응을 연구하였다. 또한, 자일렌의 이성화 반응과 밀접한 관계가 있는 제올라이트 촉매의 산특성도 조사하였다. Na^+, K^+, Cs^+ 금속이온이 교환된 시료의 산성도는 양이온의 크기가 증가함에 따라 감소하였고, Mg^(2+), Ca^(2+), Ba^(2+) 금속이온이 교환된 경우는 양이온의 크기가 증가함에 따라 산성도가 약간 증가하였다. 이성화 반응이 진행됨에 따라 제올라이트 표면에 코크가 침적되어 반응물이 활성점에 확산되어 가는 것을 방해하며, 이로인해 o-xylene의 전환율이 급격히 감소하였다. 금속이온 교환된 시료에서 산성도가 감소함에 따라 o-xylene의 전환율은 감소하였고, p-xylene의 선택도는 증가하였다. 이 결과로부터 xylene의 전환율과 선택도는 산성도와 밀접한 관계가 있음을 알 수 있다. Isomerization of o-xylene on the metal ion-exchanged natural zeolite and the acid property of these catalysts which was closely related to the isomerization of xylene were studied. With the exchange of metal ion by Na^+, K^+ and Cs^+, the acidity was decreased with increasing cation size, but with the exchange by Mg^(2+), Ca^(2+) and Ba^(2+), slight increase of acidity was found. As reaction time of isomerization was increased, coke was deposited on the surface of zeolite so that the diffusion of reactant onto the active site was disturbed and the conversion of o-xylene was reduced rapidly. When metal ions were exchanged, the conversion of o-xylene was decreased with decrease of the acidity and the selectivity of p-xylene was increased. From these results, it could be found that the conversion and the selectivity of xylene were closely related to the acidity of zeolite catalyst.

니트 갑피를 활용한 스니커즈의 스타일 유형 및 디자인 특성

이재영,Lee, Jae-Young 한국콘텐츠학회 2022 한국콘텐츠학회논문지 Vol.22 No.10

This study aims to propose the directions of design strategies and product development by analyzing the style types and design features of sneakers using the knitted upper which has been rapidly increasing due to merits in a variety of aspects including goods, production and marketing aspects. To this end, this study analyzed total 924 style types which had been gaining popularity in online markets and brand products drawing attention in the sneaker market with the knitted upper and their design features. In accordance with the analysis results, uniqueness was identified as the first merit. The unique hybrid style and design of sneakers with the knitted upper have been established without complying with the conventional materials and production techniques. The next merit was multimodality. The sneakers with the knitted upper create multiple images highlighting each feature of colors and materials by mixing those elements in various ways. The third merit was experimentality. The sneakers with the knitted upper have been attempted decisive change of designs by combining more engineering approach and new materials and techniques than existing sneakers. In these days when the sneaker market has been gradually expanded, the analysis results of this study reflecting the industrial trends will provide the fundamental data for a variety of research activities related to shoes and for the direction of brand planning in the relevant industries.

DGEBA / MDA / GN 계의 기계적 성질 및 파단 특성

이재영,심미자,김상욱 ( Jae Young Lee,Mi Ja Shim,Sang Wook Kim ) 한국공업화학회 1995 공업화학 Vol.6 No.2

DGEBA(diglycidyl ether of bisphenol A)/MDA(4,4`-methylene dianiline)/GN(glutaronitrile)계의 기계적 성질 및 파단 특성을 살펴보기 위해 GN의 함량에 따른 충격시험과 인장시험을 행하였고, SEM을 통하여 파단면을 관찰하였다. GN의 함량이 증가함에 따라 충격강도가 증가하였으며, GN 함량이 20phr인 경우에는 48% 개선되었다. 그러나 인장강도는 감소하였다. DGEBA/MDA 계의 파단면은 brittle한 형상을 나타내었고, GN이 첨가된 계는 상대적으로 ductile한 형상을 나타내었으며, 변형이 일어난 것을 확인할 수 있었다. To investigate the mechanical properties and the fracture characteristics of DGEBA/MDA/GN system, impact test and tensile test were performed with various GN contents. The fracture surface was observed by SEM. Impact strength increased with the increase of GN content and improved about 48% at 20phr of GN content. But tensile strength decreased with the increase of GN content. The fracture surface of DGEBA/MDA system without GN displayed typically brittle morphology, but that of the system with GN showed relatively ductile morphology and deformation was found.

흡인성 화상을 입은 환자에서 관찰된 후두점막의 악성변화 1례

이재영,이길준,안동빈,손진호,Lee, Jae Young,Lee, GilJoon,Ahn, Dongbin,Sohn, Jin Ho 대한후두음성언어의학회 2017 대한후두음성언어의학회지 Vol.28 No.2

Laryngeal neoplasm is the second most common malignancy of the upper aerodigestive tract. About 85% to 95% of laryngeal malignancies are squamous cell carcinoma that arises from the epithelial lining of the larynx. The exact cause of laryngeal neoplasm is unknown, but certain risk factors can affect the chances of developing it. Chronic inflammation is a mutagen factor confirmed in the carcinogenesis of various tumor. Inhalation injuries cause histopathologic damage to laryngeal mucosa and inflammation change. This long term inflammation may leads to the development of dysplasia and malignant transformation. Recently, we experienced a case of malignant transformation of laryngeal mucosa after inhalation injury patient 25 years ago. Herein, we reported this rare case and review the relevant literature.

탄소성 거동의 유한요소해석 후처리 방법

이재영,Lee, Jae-Young 한국전산구조공학회 2009 한국전산구조공학회논문집 Vol.22 No.5

컴퓨터의 성능이 향상되고 해석 알고리즘이 개선될수록 유한요소 모델링은 정교해지고 복잡해지는 경향이 있으며, 그에 상응하여 후처리 기술도 다양하게 발전하게 되었다. 이와같이 하드웨어적, 소프트웨어적인 진전을 바탕으로 탄소성해석에서는 더욱 세분화된 단계적 증분과 반복의 중간 계산 결과를 이용하여 탄소성 거동을 관찰하고 분석하는 것이 실용적인 의미를 갖게 되었다. 이 논문은 유한요소해석을 통해서 얻은 계산 결과로 부터 탄소성 재료의 역학적인 거동을 이론적으로 구성하고, 컴퓨터 그래픽스로 가시화하는 새로운 후처리 방법에 관하여 기술하였다. 또한 소성 거동의 진행을 표현하는 새로운 방법과 해석의 중간단계에서 생성된 데이터를 항복곡면과 응력경로의 형태로 재구성하거나 또는 Mohr원과 파괴포락선의 형태로 재구성하여 탄소성 거동을 분석하고 이해하는 방법을 제안하였다. The postprocessing technology has been advanced diversely to accommodate the tendency of increasingly refined and complicated practices of finite element modeling in pace with enhanced capabilities of computers and improved algorithm of equation solvers. As a result of such progresses in both hardware and software, it became practically meaningful to inspect and analyze the elasto-plastic behavior using the intermediate results from the increasing number of incremental and iterative processes. This paper is concerned about the new methods of postprocessing with computer graphic visualization of elasto-plastic behavior on the basis of the theoretically reorganized analysis results. This paper proposes a new method of rendering the plastic zone, and new approaches of analyzing and interpreting the elasto-plastic behavior using the graphical information visualized in the form of the yield surface and the stress path, or in the form of the Mohr circles and the failure envelope.

EQCM를 이용한 금전극과 티타늄전극에서의 이산화납박막의 결정성장연구

이재영,엄성현,김두헌,최진섭,남종우,탁용석 ( Jae Young Lee,Sung Hyun Um,Doo Hun Kim,Jin Sub Choi,Chong Woo Nam,Yong Sug Tak ) 한국공업화학회 1997 한국공업화학회 연구논문 초록집 Vol.1997 No.0

영어의 모음체계 연구

이재영,Lee Jae-Young 대한음성학회 1999 말소리 Vol.38 No.-

In this paper I have surveyed vowel phonemes in a variety of English accents and have proposed the vowel systems of English. The English accents covered in this paper include General American English, Northeastern American English, Western American English, Southern British English, Northern British English, Scottish English, Southern Irish English, Northern Irish English, Australian English, and New Zealand English. The vowel systems proposed here reflect the acoustic information of vowels and phonological aspects of English. This paper offers an Optimality Theory-based analysis of the English vowel systems by appealing to independently motivated constraints. This paper, following Flemming(1995), makes an assumption that the vowel system in question is selected in output as an optimal candidate by a given constraint ranking, the assumption which is different from the view that the vowel system is fixed in input. The analysis proposed here gives an answer to why a specific vowel system is selected and why dialectal variations come about. It is shown in this paper that the vowel system selected in a specific dialect comes from an optimal satisfaction of a given constraint ranking and that dialectal differences result from dynamic permutations of the same constraints. The constraint-based analysis proffered here accounts well for the similarities and differences among dialects in regard to the vowel system.