• Journal of Gastric Cancer
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• 제21권2호
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• pp.191-202
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• 2021

Purpose: A near-infrared (NIR) fluorescence imaging is a promising tool for cancer-specific image guided surgery. Human epidermal receptor 2 (HER2) is one of the candidate markers for gastric cancer. In this study, we aimed to synthesize HER2-specific NIR fluorescence probes and evaluate their applicability in cancer-specific image-guided surgeries using an animal model. Materials and Methods: An NIR dye emitting light at 800 nm (IRDye800CW; Li-COR) was conjugated to trastuzumab and an HER2-specific affibody using a click mechanism. HER2 affinity was assessed using surface plasmon resonance. Gastric cancer cell lines (NCI-N87 and SNU-601) were subcutaneously implanted into female BALB/c nu (6-8 weeks old) mice. After intravenous injection of the probes, biodistribution and fluorescence signal intensity were measured using Lumina II (Perkin Elmer) and a laparoscopic NIR camera (InTheSmart). Results: Trastuzumab-IRDye800CW exhibited high affinity for HER2 (K_D=2.093(3) pM). Fluorescence signals in the liver and spleen were the highest at 24 hours post injection, while the signal in HER2-positive tumor cells increased until 72 hours, as assessed using the Lumina II system. The signal corresponding to the tumor was visually identified and clearly differentiated from the liver after 72 hours using a laparoscopic NIR camera. Affibody-IRDye800CW also exhibited high affinity for HER2 (K_D=4.71 nM); however, the signal was not identified in the tumor, probably owing to rapid renal clearance. Conclusions: Trastuzumab-IRDye800CW may be used as a potential NIR probe that can be injected 2-3 days before surgery to obtain high HER2-specific signal and contrast. Affibody-based NIR probes may require modifications to enhance mobilization to the tumor site.

• 항공우주시스템공학회지
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• 제16권1호
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• pp.56-69
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• 2022

주요 선진국들은 극초음속 무기체계 개발에 경쟁을 가속화하고 있다. 북한은 잠수함 발사 탄도 미사일을 탑재한 신형 잠수함 건조를 눈앞에 두고 있고, 한국은 핵추진 잠수함, 경 항공모함, 신형 미사일 개발 등 다양한 전력 증강 계획을 추진하고 있다. 동북 아시아 지역은 한국을 비롯하여, 북한, 미국, 중국, 러시아, 일본이 군사적 경쟁 속에서 긴장감을 늦출 수 없는 상황을 지속하고 있다. 이에 따라, 이들 국가들의 무기체계 개발 경쟁도 전 세계의 최고 수준을 보여주고 있으며, 그 중심에 한국이 놓여있다. 본 논문에서는 주요 국가들이 개발 경쟁을 하고 있는 극초음속 무기체계가 왜 필요한지 기술적 분석을 통해 그 의미를 알아보고, 한국군이 추구하고자 하는 군사력 발전 방향을 분석해 본다. 그리고 극초음속 무기체계 개발을 위해 극복해야 하는 기술적 한계와 추진 전략에 대해 제안하고자 한다.

• 한국세라믹학회지
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• 제45권9호
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• pp.524-530
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• 2008

Anti-Reflective (AR) thin film coatings of $SiO_2$ (n= 1.48) and $TiO_2$ (n=2.17) were deposited by ion-beam assisted deposition (IBAD) with End-Hall ion source and conventional electron beam (e-beam) evaporation to investigate the effect of deposition method on the refractive indicies (n) of the fIlms. Green-light generation using a GaAs laser diode was achieved via excitation of the second harmonic. The latter resulted from the transmission of the fundamental guided-mode wave of 1064 nm through periodically poled $LiNbO_3$. Large differences in the refractive indicies of each of the layers in the multilayer coating may improve AR performance. IBAD of $SiO_2$ reduced its refractive index from 1.45 to 1.34 at 1064 nm. Conversely, e-beam evaporation of $TiO_2$ increased its refractive index from 1.80 to 2.11. In addition, no fluctuations in absorption at the wavelength of 1064 nm were found. The results suggest that films prepared by different deposition methods can increase the effectiveness of multilayer AR coatings.

• Journal of Periodontal and Implant Science
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• 제33권4호
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• pp.705-715
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• 2003

Procedures for treatment of molar furcation invasion defects range from open flap debridement, apically repositioned flap surgery, hemisection, tunneling or extraction, to regenerative therapies using bone grafting or guided tissue regenerative therapy, or a combination of both. Several clinical evaluations using regenerative techniques have reported the potential for osseous repair of treated furcation invasions. Regenerative treatment of maxillary molars are more difficult due to the multiple root anatomy and multiple furcation entrances therefore, purpose of this study was to evaluated histologically compomer and Ketac Silver as a barrier in the treatment of a bi-furcated maxillary premolar. Five adult beagle dogs were used in this experiment. With intrasulcular and crestal incision, mucoperiostcal flap was elevated. Following decortication with 1/2 high speed round bur, furcation defect was made on maxillary premolar. 2 month later one premolar was filled with compomer and the other premolar was filled with Ketac Silver. After 4, 8 weeks, the animals were sacrificed by vascular perfusion. Tissue block was excised including the tooth and prepared for light microscope with H-E staining. Results were as follows. 1. Compomer & Ketac Silver restoration were encapsulated fine connective tissue. 2. In 4 weeks, compomer & Ketac Silver restoration slightly infiltrated inflammatory cells but not disturb the new bone or new cementum formation. 3. In 8 weeks, compomer & Ketac Silver restoration were less infiltrated iflammatory cell and encapsulated fine connective tissue. 4. Therefore, compomer & Ketac Silver filling to the grade III maxillary furcations with multiple root anatomy and multiple furcation entrances is possible clinical method and this technique is useful method for maxillary furcation involvement but it is thought that periodic maintenance should be needed

• Childhood Kidney Diseases
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• 제10권2호
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• pp.174-181
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• 2006

Purpose : To analyse the results of the renal biopsies and the clinical diagnoses of patients who had undergone percutaneous kidney biopsies in the department of pediatrics at Kyunghee University Hospital for 22 years from 1984 to 2005. Methods : We retrospectively reviewed the medical records of 1559 patients and analyzed the chief complaints that led to a renal biopsy, age, sex, histopathologic findings and diagnosis. Routine kidney biopsies were performed by automated gun biopsy guided by real time ultrasonography. The diagnoses were made based on the specimen's light microscopy, immunofluorescence microscopy and electron microscopy findings and clinical symptoms and signs. Results : The mean age of the patients was 10 years with the male to female ratio being 1.3:1. The chief complaints that led to a renal biopsy included hematuria only(753 cases, 48.3%), proteinuria only(125 cases, 8.0%) and hematuria combined with proteinuria(537 cases, 34.4%). The most frequent histopathological finding was primary glomerular disease(75.4%) which included IgA nephropathy(30.1%) and mesangial proliferative glomerulonephritis(27.6 %). Systemic disease comprised 11.4% which included Henoch-$Sch\ddot{o}nlein$ nephritis(10.5%) and lupus nephritis(0.8%). Alport syndrome was found in 1.1% of cases which was attributed to hereditary causes. 628 children(40.3%) visited the clinic due to abnormal school urine screening abnormalities and among these, 237 children had mesangial proliferative glomerulonephritis and 234 children who had IgA nephropathy were managed thereafter. Conclusion : IgA nephropathy and mesangial proliferative glomerulonephritis were the two major forms of primary glomerulonephritis found in Korean children who had kidney biopsies from 1984 to 2005.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제10권1호
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• pp.341-363
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• 2016

Haze or fog is a common natural phenomenon. In foggy weather, the captured pictures are difficult to be applied to computer vision system, such as road traffic detection, target tracking, etc. Therefore, the image dehazing technique has become a hotspot in the field of image processing. This paper presents an overview of the existing achievements on the image dehazing technique. The intent of this paper is not to review all the relevant works that have appeared in the literature, but rather to focus on two main works, that is, image dehazing scheme based on atmospheric veil and image dehazing scheme based on dark channel prior. After the overview and a comparative study, we propose an improved image dehazing method, which is based on two image dehazing schemes mentioned above. Our image dehazing method can obtain the fog-free images by proposing a more desirable atmospheric veil and estimating atmospheric light more accurately. In addition, we adjust the transmission of the sky regions and conduct tone mapping for the obtained images. Compared with other state of the art algorithms, experiment results show that images recovered by our algorithm are clearer and more natural, especially at distant scene and places where scene depth jumps abruptly.

• 한국ITS학회 논문지
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• 제17권5호
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• pp.48-54
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• 2018

4차 산업시대와 함께 스마트 팩토리가 대두되고 있으며, 다품종 소량생산 시대를 맞이하여 무인 운반차는 작업공간에서 물건을 운반하고 정리하는 무인 운반차의 활용도가 빠르게 증대하고 있다. 기존의 무인 운반차는 실내 위치인식 및 이동을 위해 유도선 방식, 위치기반 방식을 사용하여 자신의 위치를 검출하였고 이러한 방법은 초기 고비용 및 유지/관리 보수의 단점이 있었다. 본 논문에서는 단점을 해결하고자 물류창고의 White LED 마커를 이용하여 위치 데이터와 White LED 마커 인식 이미지 데이터를 활용하여 칼만 필터를 통해 무인 운반차의 직전경로를 예측함에 하는 방안에 대해 검증하였다. 이를 통해 격자구조에서 대부분을 차지하는 직선 이동에 대한 신뢰성을 확보하였다. 또한 추가적인 위치 센서에 대한 의존도 또한 줄일 수 있을 것이라 예상된다.

• 한국인터넷방송통신학회논문지
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• 제17권6호
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• pp.83-88
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• 2017

본 논문에서는 유도무기용 탐색기의 송신 시 고 전력 송수신 신호 분리를 위한 Ka-대역 밀리미터파 3-포트 도파관 순환기를 설계, 제작하였으며 상온에서의 S-parameter 시험, 고 전력 시험, 운용 온도 시험을 통해 성능을 검증하였다. 탐색기 안테나와의 인터페이스 설계 및 소형, 경량화를 위한 표준 도파관 높이의 half-size 설계를 적용하였다. 전기적 성능 구현을 위해 시뮬레이션을 통한 구성 부품인 영구자석, 페라이트 최적 형상 설계 및 포트 별 튜닝 유전체 적용을 통해 성능을 최적화 하였다. 설계된 도파관 순환기는 중심 주파수 Fc 기준 ${\pm}1000MHz$의 대역에서 -20 dB 이하 반사 손실, 0.5 dB 이하 삽입 손실, -23 dB 이하 분리도 특성을 가지며, 측정 결과는 설계 결과와 유사함을 확인하였다.

• Journal of Periodontal and Implant Science
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• 제25권2호
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• pp.407-417
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• 1995

In order to evaluate the effect of platelet-derived growth factor(PDGF-BB) and guided tissue regeneration(GTR) technique on the regeneration of destructed periodontal tissue,intentional through-and-through furcation defects(4mm in height) were made on both mandibular 2nd and 4th premolars of 8 adult male dogs(30-40lb). Experimental group 1 was composed of the premolars that were treated by only topical application of PDGF-BB with 0.05M acetic acid without any barrier membrane. Experimental group 2 was composed of the premolars that were treated by GTR with expanded polytetrafluoroethylene membrane(ePTFE : Gore-tex periodontal material, USA). Experimental group 3 was composed of the premolars that were treated by GTR with ePTFE after topical application of PDGFBE. Control group was composed of the premolars that were treated by coronally positioned flap operation only without use of PDGF-BB and ePTFE membrane. All ePTFE membranes were carefully removed 4 weeks after regenerative surgery, and all experimental animals were sacrificed 8 weeks after regenerative surgery. The light microscopic findings were as follows ; (1) In experimental group 1, rapid new bone formation along the-root surface with multiple ankylosis and root resorption by multinucleated giant cells, and dense connective tissue in the central portion of the furcation defects were observed. (2) In experimental group 2, it was observed that the furcation defects were filled with newly formed bone, Sharpey's fibers were embedded into new cementum on root dentin of furcation fornix area, but the central portion and the area under furcation fornix were still filled with dense connective tissue. (3) In experimental group 3, the furcation defects were regenerated with newly formed dense bone and regular periodontal ligament with Sharpey's fibers embedded into newly formed cementum and bone underneath fornix area. (4) In control group, unoccupied space, apical migration of epithelium, dense infiltration of inflammatory cells in subepithelial connective tissue in relation to heavy plaque accumulation, and root resorption by inflammatory reaction were shown, but any new cementum formation on resorbed dentin surface could not be observed. The present study demonstrated that the combined therapy of PDGF-BB and GTR could enhance the regeneration of destructed periodontal tissue.

• 방송공학회논문지
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• 제21권5호
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• pp.770-781
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• 2016

안개 영상은 색상 정보와 경계선 정보가 줄어들기 때문에 사물의 식별에 어려움이 발생한다. 안개 제거를 위한 대표적인 알고리즘은 Dark Channel Prior(DCP)를 이용한 방식으로 안개 영상의 색상 정보를 이용하여 안개의 전달량을 추정 한 후 안개를 제거한다. 그러나 색상 정보를 바탕의 안개량 추정을 할 경우, 영상 내에 흰색 사물이나 광원과 같이 높은 밝기의 사물이 있는 영역에 대해 안개량 및 전달량을 오추정하는 문제점이 발생한다. 본 논문에서는 안개 영상의 백색 영역을 중심으로 색 정규화를 적용 한 후, 안개량 오추정 영역을 주변 안개값으로 보정하여 안개값 오추정 문제를 개선하였다. 또한 개선된 안개량 추정 결과를 바탕으로 전달량 계산 후 전달량 정련을 통해 안개 영상의 화질을 개선하였다.