• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2017년도 춘계공동학술대회
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• pp.146-146
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• 2017

현대의 스마트폰 및 태블릿pc등을 가능하게 만든 집적 기술 중의 하나는 3차원 집적 회로(3D-IC)와 같은 패키징 기술이다. 이러한 첨단 3차원 집적 기술은 메모리집적을 통한 대용량 메모리 모듈 개발뿐만 아니라, 메모리와 프로세서의 집적, high-end FPGA, Back side imaging (BSI) 센서 모듈, MEMS 센서와 ASIC 집적, High Bright (HB) LED 모듈 등에 적용되고 있다. 3D-IC의 3차원 모듈 제작 시에는 기존에 발생하지 않았던 여러 가지 파괴 모드들이 발생하고 있는데 Thermal/Photonic Emission 장비 등 기존의 2차원 결함분리 (Fault Isolation) 기술로는 첨단의 3차원 적층 제품들에서 발생하는 불량을 비파괴적으로 혹은 3차원적으로 분리하는 것이 불가능하므로, 비파괴 3차원 결함 분리 기술은 향후 선행 제품 적기 개발에 매우 필수적인 기술이다. 본 연구는 3D-IC 반도체의 비파괴적 내부결함 검사를 위하여 가시광선-근적외선 대역(351nm~1770nm)의 InGaAs (Indium Galium Arsenide) 계열 영상검출기 (imaging detector)를 사용하여 분광 시스템 광학 설계를 통한 초분광 영상 기반 검출 모듈을 제작하였다. 제작된 초분광 영상 기반 검출 모듈을 이용하여 구리 회로 위에 실리콘 웨이퍼가 3단 적층 된 반도체 더미 샘플의 초분광 영상을 촬영하였으며, 촬영된 초분광 영상에 대하여 Chemometrics model 기반의 분석기술을 적용하여 실리콘 웨이퍼 내부의 집적 구조에 대한 검사가 가능함을 확인하였다.

• 한국소음진동공학회논문집
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• 제24권2호
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• pp.123-130
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• 2014

An ultrasonic magnetostrictive transducer-based phased-array system for imaging defects in plate structures is newly proposed. In that most ultrasonic phased array systems rely on piezoelectric transducers or electromagnetic acoustic transducers, this system has its own unique feature of employing magnetostrictive transducers. Interest in using a phased array system using magnetostrictive transducers has been recently reported for pipe inspection but no such system has been developed for plate inspection. In this investigation, we aim to propose a phased array system using OL-MPTs (Omnidirectional Lamb wave Magnetostrictive Patch Transducers) for plate inspection. The developed system consists of a multi-channel function generator, power amplifiers, preamplifiers and a data acquisition unit. In the process of its development, each of the units must be checked and in doing so, we suggest types of ultrasonic wave experiments that should be carried out. Finally, the phased system using a transducer array composed of eight OL-MPTs is newly configured and is applied for actual crack detection experiments.

• 대한디지털의료영상학회논문지
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• 제8권1호
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• pp.51-55
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• 2006

moving photocarrier grating(MPG)기술을 이용하여 디지털 X-선 변환물질 a-Se:As 필름에서 As 첨가효과에 관하여 연구하였다. 이 방법은 시료를 조사하기 위하여 주파수를 변화시킨 2개 레이저 빔의 중첩으로 얻어진 움직이는 간섭패턴을 이용한다. 시료의 수송변수는 시료에서 변조 방향으로 유도되는 grating-속도에 의존하는 전류밀도로부터 얻어진다. As 첨가에 따른 a-Se 필름의 전자와 정공 이동도 그리고 재결합 수명을 구하였다. 전자의 이동도는 결함 상태 때문에 As 첨가에 따라 감소하는 반면, 특히 a-Se 필름에 0.3% As 첨가할 때 정공 이동도와 재결합 수명이 증가하였다. MPG 기술로 얻은 As가 첨가된 a-Se 필름의 수송성질을 a-Se:As로 제작한 X-선 detector의 X-선 감도와 비교하였다. 실험결과 0.3% As가 첨가된 a-Se으로 제작한 X-선detector가 가장 우수한 X-선 감도를 나타내었다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 추계학술대회 논문집 Vol.15
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• pp.436-439
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• 2002

Recently, It has performed that the basic research of the photoconductive material and the development and application of the digital radiograph detector which is divided into the direct and indirect method. The objective of this study investigate the effect of the electric characteristic about changing the composition of Arsenic in hybrid detector system for compensating a defect of conventional. We fabricated samples using the amorphous Selenium and Arsenic alloy with various concentrations of the Arsenic{seven step 0.1%, 0.3%, 0.5%, 1%, 1.5%, 3%, 5%). And using EFIRON optical adhesives the formed multi-layer$(Gd_{2}O_{2}S(Eu^{2+}))$ composed phosphor layer. X-ray and light sensitivity was measured to study x-ray response characteritics. As results, highest value was measured as output net charge and SNR were $315.7pC/cm^2/mR$ and 99.4 at 0.3%As doping ratio.

• Journal of Korean Neurosurgical Society
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• 제38권6호
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• pp.413-418
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• 2005

Objective : Although an encephaloduroarteriosynangiosis procedure using the superficial temporal artery [STA-EDAS] is an effective indirect bypass method in children with moyamoya disease[MMD], there is still a need for an additional bypass operation that can cover the area of the posterior circulation. The goal of this study is to evaluate the efficacy of the EDAS procedure using the occipital arteries [OA-EDAS]. Methods : From August 2003 to April 2004, We performed OA-EDAS in sixteen patients with MMD who have a circulatory insufficiency in the territory of the posterior cerebral artery[PCA]. The medical records were reviewed retrospectively. The surgical outcomes, including the changes in neurological status and imaging studies, with the degree of neovascularization on the cerebral angiogram, and the hemodynamic changes on single-photon emission computed tomography[SPECT], were analyzed. Results : These 16 children consisted of 5 boys and 11 girls aged 2 to 9 years. The clinical outcome of their PCA symptoms, such as visual transient ischemic attacks[TIAs] or visual field defect, was favorable in 14 patients of 16. Nine patients of 11 who underwent follow up magnetic resonance imaging[MRI] showed favorable MRI changes. On angiogram most of the patients exhibited good or fair revascularization of the PCA territory [7 of 8]. The hemodynamic changes on SPECT in the PCA territory after surgery showed improved vascular reserve in 13 of the 16 territories. Conclusion : OA-EDAS is a safe and efficacious revascularization procedure in patients with MMD who have compromised cerebral perfusion in PCA territory, or with visual TIAs.

• 대한두개안면성형외과학회지
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• 제14권1호
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• pp.69-72
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• 2013

Lateral eyebrow mass with primary skull lesion are rare in pediatric population. Although epidermoid cyst and dermoid cyst are the most commonly encountered skull lesions in pediatric population, Langerhans cell histiocytosis (LCH) is rarely reported. We report a case of LCH arising from the lateral eyebrow with osteolytic lesion involving the frontal bone. A 5-year-old boy was presented with a hard, fixed mass in his lateral eyebrow. Contrast magnetic resonance imaging revealed inhomogeneous enhancement of the mass with direct invasion of the frontal bone and adjacent dura mater. Under general anesthesia, linear incision at the lateral eyebrow region was made. Intraoperative evaluation revealed hard, fixed and well-defined soft tissue mass. The final extirpated mass was $2.5{\times}2.4cm$ in size, and was accompanied by a $1{\times}1cm$ sized defect on the frontal bone with intact dura mater. The surgical wound was closed primarily by a layer-by-layer fashion. Histologic examination was later performed for definite diagnosis. The histologic examination revealed abnormal proliferation of Langerhans cell with granuloma formation. Radionuclide bone scan and positron emission tomography was taken and revealed free of multi-organ involvement. At 3 months after surgery, natural looking contour at the lateral eyebrow region was observed with no tumor recurrence. Differential diagnosis of the hard and fixed mass at the lateral eyebrow region affecting the primary skull lesion from pediatric population includes epidermoid cyst, dermoid cyst and LCH. Generally, brief physical examination with plain X-ray view can be performed for clinical evaluation, but for a definite diagnosis, contrast MRI may be helpful.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제25권2호
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• pp.147-162
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• 2022

Purpose: To design a prospective study on endovascular closure of congenital portosystemic shunts. The primary endpoint was to assess the safety of endovascular closure. The secondary endpoint was to evaluate the clinical, analytical and imaging outcomes of treatment. Methods: Fifteen patients (age range: 2 days to 21 years; 10 male) were referred to our center due to congenital portosystemic shunts. The following data were collected prior to treatment: age, sex, medical history, clinical and analytical data, urine trimethylaminuria, abdominal-US, and body-CT. The following data were collected at the time of intervention: anatomical and hemodynamic characteristics of the shunts, device used, and closure success. The following data were collected at various post-intervention time points: during hospital stay (to confirm shunt closure and detect complications) and at one year after (for clinical, analytical, and imaging purposes). Results: The treatment was successful in 12 participants, migration of the device was observed in two, while acute splanchnic thrombosis was observed in one. Off-label devices were used in attempting to close the side-to-side shunts, and success was achieved using Amplatzer™ Ductus-Occluder and Amplatzer™ Muscular-Vascular-Septal-Defect-Occluder. The main changes were: increased prothrombin activity (p=0.043); decreased AST, ALT, GGT, and bilirubin (p=0.007, p=0.056, p=0.036, p=0.013); thrombocytopenia resolution (p=0.131); expansion of portal veins (p=0.005); normalization of Doppler portal flow (100%); regression of liver nodules (p=0.001); ammonia normalization (p=0.003); and disappearance of trimethylaminuria (p=0.285). Conclusion: Endovascular closure is effective. Our results support the indication of endovascular closure for side-to-side shunts and for cases of congenital absence of portal vein.

• Investigative Magnetic Resonance Imaging
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• 제7권2호
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• pp.100-107
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• 2003

목적 : 급성심근경색을 진단하는데 있어 심장자기공명영상의 유용성을 알아보고, 생존심근을 평가하는데 있어 Tl-201 심근관류 SPECT와 비교하고자 하였다. 대상 및 방법 : 흉통 및 호흡곤란이 있는 환자 중 심장자기공명영상과 Tl-201 SPECT를 시행한 17명을 후향적으로 조사하였다. 심장자기공명영상에서는 T2강조영상에서 심벽의 고신호 강도 유무, 영화영상에서 심벽 운동, Gd-DTPA 조영 증강 후 좌심실 벽의 관류 결손 및 주입 15분 후의 지연조영증강 유무를 평가하였다. T1-201 SPECT에서는 아데노신 부하 영상과 휴식기 영상을 얻어 관류 결손 유무와 관류 결손시 가역성 여부를 평가하였다. 결과 심장자기공명영상과 T1-201 SPECT 모두 급성심근경색을 진단하는데 통계적으로 의미가 있었고, T2강조영상, T1-201 SPECT, 지연조영증강 및 심벽운동 순으로 연관성이 있는 것으로 나타났고, 관류 결손은 통계적 유의성이 없었다. 생존심근 평가에 있어서는 두 검사간 유의한 차이가 없었으며, T2강조영상과 관류영상에서 T1-201 SPECT와 높은 일치율, 지연조영증강 및 심벽운동은 낮은 일치율을 보였다. 결론 : 심장자기공명영상은 급성심근경색을 진단하는데 매우 유의한 진단율을 보였고, 생존 심근여부의 판단에 있어 SPECT와 높은 일치율을 보였다. 그러나 각 검사별 판독 기준과 방법에서 많은 연구가 필요할 것으로 생각된다.

• Nuclear Medicine and Molecular Imaging
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• 제43권6호
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• pp.519-525
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• 2009

목적: 심근의 F-18 FDG 섭취는 다양한 인자에 의해 영향을 받으며, 가역적인 허혈성 심질환이 있을 경우 심근에서 포도당 대사가 증가된다고 알려졌다. 이 연구에서는 허혈성 심질환의 과거력이 없는 종양 환자에서 시행한 F-18 FDG PET/CT에서 심근 섭취 정도 및 분포를 관찰하고, 심근 관류 SPECT와 비교하여 F-18 FDG 심근 섭취 소견으로 심근 허혈을 예측할 수 있는지를 알아보고자 하였다. 대상 및 방법: 2005년 1월부터 2009년 6월까지 F-18 FDG PET/CT를 시행한 환자 중 3개월 이내에 Tc-99m sestamibi 심근 관류 SPECT를 시행한 환자 77명을 대상으로 후향적 분석을 시행하였다. 결과: 77명의 환자 중 F-18 FDG PET/CT에서 심근에 섭취가 증가하여 있는 경우는 55명(71.4%)이었다. 이 중 40명은 균등 심근 섭취를 보였고 15명은 국소 심근 섭취를 보였다. 균등 F-18 FDG 섭취 증가를 보인 40명의 환자 중 17명(42.5%)에서 격벽에 섭취 감소가 관찰되었으나, 심근 관류 SPECT상 유의한 관류 이상은 관찰되지 않았다. 전체 심근에 균등한 섭취를 보인 23명(57.5%) 중 1명(4.3%)에서 하벽에 가역적인 관류 결손이 관찰되었고, 1명(4.3%)에서 측벽에 비가역적인 관류 결손이 관찰되었으며, 21명(91.3%)에서는 관류 결손이 관찰되지 않았다. 국소 심근 섭취를 보인 15명 중 9명(60.0%)은 기저부에 국소 섭취 증가를 보였고, 이 중 1명에서 심첨측벽에 가역적인 관류 결손이 관찰되었다. 국소적인 심근 섭취를 보인 나머지 6명(40.0%)의 환자 중에서 4명(66.7%)의 환자에서 가역적인 관류 결손이 관찰되었다. 결론: 전신 F-18 PET/CT에서 심근에 격벽 감소나 기저부 증가를 제외한 국소적인 섭취 증가가 관찰되는 경우에는 허혈성 심질환의 가능성이 있으므로 추가적인 진단 검사가 필요하다.

• 대한핵의학회지
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• 제27권1호
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• pp.59-64
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• 1993

To evaluate the usefulness and differences in diagnosing coronary artery disease (CAD) between men and women of intravenous dipyridamole $^{99m}Tc$-MIBI myocardial SPECT, we obtained $^{99m}Tc$-MIBI myocardial SPECT and compared with the findings of coronary angiographies. Ninety eight male and 37 female patients who underwent dipyridamole $^{99m}Tc$-MIBI myocardial imaging within one month of cardiac catheterization were studied. Scans were considered abnormal if perfusion defect was detected and the defect size was more than 12% for left anterior descending artery (LAD) and circumflex (LCX) and 8% for right coronary artery (RCA) territories. Lesions${\geqq}$50% luminal diameter narrowing were considered significant CAD. Overall sensitivity for detection of CAD was 94.3% in men and 96.4% in women; specificity was 70% in men and 52.6% in women (P=not significant, ns). Vessel-matched sensitivity was 75.3% in men and 72.7% in women (P=ns): specificity was 84.6% in men and 67.9% in women (P < 0.025). For individual coronary artery, the sensitivity in men and women was 87.7%, 81.8% for LAD; 78%, 83.3% for RCA and 52.2%, 46.7% for LCX (P=ns): the specificity was 80%, 40% for LAD (P<0.01), 82.5%, 68.4% for RCA, 88.9%, 86.4% for LCX (P=ns). The hemodynamic parameter after intravenous dipyridamole in men and women were significantly changed; the heart rate was increased and systolic, diastolic blood pressure was decreased. Adverse effects were reported in 58.8% of men and 72.7% in women (P=ns). The incidence of chest pain and headache were higher in women. There was no significant difference in the incidences of nausea, abdominal pain, dizziness, facial flushing, dyspnea. In conclusion, dipyridamole $^{99m}Tc$-MIBI myocardial SPECT is a safe, noninvasive test for evaluation of CAD. There was no gender difference to detect CAD, but more false-positive rate in women especially in the territory of LAD.