• Title/Summary/Keyword: 평활도

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A Study of Digital Image Restoration for Modified PEM Gradient Algorithm (변형된 PEM 그래디언트 알고리즘을 이용한 디지털화상처리에 관한 연구)

  • Song, Min-Koo
    • The Transactions of the Korea Information Processing Society
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    • 제7권1호
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    • pp.313-320
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    • 2000
  • PEM algorithm cannot expend repeated algorithm, if penalty function is transcendental function. However, OSL algorithm has an advantage that repeated algorithm is easily derived, even though penalty function which has a complicated transcendental function. In spite of this advantage, this algorithm is restricted in convergence region of smoothing constant which increase penalized log-likelihood, so we cannot get the optimal image restoration because it cannot provide us with a various smoothing constant value for the digital image restoration. In this paper, in order to resolve the disadvantage of OSL algorithm, we would like to suggest the algorithm with smoothing constant enlarge the tolerance limit range of convergence and to find not only properties of its convergence but also usefulness of suggested algorithm through digital image simulation.

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Parasitic Leiomyoma with Lymphatic Dilatation in Trocar Port-Site of Abdominal Wall: A Case Report (트로카 삽입 부위에 생긴 림프관 확장을 동반한 기생 평활근종: 증례 보고)

  • Gayoung Jeon;Seo Young Park
    • Journal of the Korean Society of Radiology
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    • 제84권1호
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    • pp.280-285
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    • 2023
  • Uterine leiomyoma is the most common benign pelvic tumor in female and being symptomatic is an indication for surgical removal. As laparoscopic surgery has been developed, some cases related to parasitic leiomyomas in the port site have been reported. A 40-year-old female who a history of previous laparoscopic surgery to remove uterine myoma 2 years ago visited in outpatient clinic of general surgery with palpable mass in left lower abdomen. Contrast enhanced abdomen CT and pelvis MRI were done to evaluate the mass. It was diagnosed parasitic leiomyoma in pathologic study after surgical removal and parasitic leiomyoma should be considered when patient visited presenting abdominal mass with the history of laparoscopic myomectomy.

Vascular Smooth Muscle Cells Secrete CXCL10 in Response to Heat Shock Protein 90 (혈관평활근세포에서 HSP90에 의한 CXCL10 증가에 관여하는 인자에 대한 연구)

  • Rhim, Byung-Yong;Kim, Do-Hyung;Kim, Koan-Hoi
    • Journal of Life Science
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    • 제21권5호
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    • pp.664-670
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    • 2011
  • Oxidative stress results in sustained release of heat shock protein 90 (HSP90) from vascular smooth muscle cells (VSMCs). We investigated whether extracellular HSP90 predisposed VSMCs to pro-inflammatory phenotype. Exposure of human aortic smooth muscle cells to HSP90 not only significantly enhanced CXCL10 secretion but also increased CXCL10 transcription. HSP90-mediated CXCL10 secretion was attenuated by OxPAPC, a TLR-2/4 inhibitor, and curcumin, a TLR-4 dimerization inhibitor. Inhibitors of diphenyleneiodium chloride and the Akt pathway also attenuated CXCL10 secretion in response to HSP90. The gene delivery of I${\kappa}$B using recombinant adenoviruses and treatment with resveratrol, which inhibit NF-${\kappa}$B activity, significantly attenuated HSP90-induced CXCL10 secretion from VSMCs. We propose that extracellular HSP90 contributes to an inflammatory reaction in the stressed vasculature by inducing CXCL10 expression of VSMCs, and that TLR-4, Akt, and NF-${\kappa}$B play active roles in the process.

The Effect of Epigallocatechin-3-Gallate on Intimal Hyperplasia after Vascular Grafting (혈관이식술 후 내막과다증식에 대한 Epigallocatechin-3-Gallate의 효과)

  • Park, Han-Ki;Song, Suk-Won;Lee, Mi-Hee;Park, Jong-Chul;Joo, Hyun-Chul;Chang, Byung-Chul;Park, Young-Hwan
    • Journal of Chest Surgery
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    • 제40권4호
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    • pp.256-263
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    • 2007
  • Background: Intimal hyperpiasia is characterized by a proliferation of vascular smooth muscle cells in the intimal layer Epigallocatechin-3-gallate (EGCG) is known to suppress smooth muscle cell proliferation. We propose that EGCG may have a protective effect against the development of intimal hyperplasia through the suppression of smooth muscle cell proliferation. Material and Method: Human umbilical vein endothelial cells (HUVEC) and rat aortic smooth muscle cells (RASMC) were cultured with different concentrations of EGCG, and proliferation and migration speed were measured. In 20 dogs, the autologous jugular veins were interposed into the carotid arteries. For the study group (n=10), the graft was stored for 30 minutes in EGCG solution and 300mM EGCG was applied to the perivascular space after grafting. After 6 weeks, the intimal and medial thickness was measured. Result: The proliferation of RASMC and HUVEC was suppressed with EGCG. The migration of RASMC was suppressed with EGCG, but that of HUVEC was not affected. In the in vivo study, the intimal thickness was thinner in EGCG group than in the control group (p<0.05), but the medial thickness did not show any difference. The intimal/medial thickness ratio was lower in the EGCG group (p<0.05). Conclusion: EGCG suppresses intimal hyperplasia after vascular grafting, and this may be mediated by prevention of migration and proliferation of vascular smooth muscle cells. The use of EGCG may offer new therapeutic modality to prevent intimal hyperplasia.

Leiomyosarcoma of the Somatic Soft Tissue: Clinical Manifestation and Treatment Results (연부조직에 발생한 평활 근육종의 임상양상 및 치료 결과)

  • Kim, Yong Sung;Kong, Chang-Bae;Cho, Wan-Hyeong;Jeon, Dae-Geun;Kim, Kyung Hoon;Song, Won Seok
    • Journal of the Korean Orthopaedic Association
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    • 제55권5호
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    • pp.397-404
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    • 2020
  • Purpose: The purpose of this study was to evaluate the treatment outcome of leiomyosarcoma (LMS) of the somatic soft tissue and investigate the prognostic factors. Materials and Methods: Seventy-two patients with soft tissue LMS (extremities and trunk) between 2001 and 2017 were reviewed retrospectively. The local recurrence and metastasis after treatment were examined. The survival rates and prognostic factors affecting survival were investigated. Only patients followed-up more than one year were included. The mean follow-up time was 41 months (range, 7-163 months). Results: The overall survival rates at five-year and 10-year were 73.6% and 66.2%, respectively. The tumor size (p=0.018), grade (p=0.017), and local recurrence (p=0.04) affected survival. Metastases developed in 31.9% (23/72) and the median post metastasis survival was 15.6 months (range, 3-78 months). Conclusion: LMS of the soft tissue developed mainly at the lower extremity. The tumor size, grade, and local recurrence were associated with survival. Post metastatic survival was generally poor despite treatment.

Studies of the Interface between the High Indium Content InGaAs QW and GaAs Layers (고 indium 농도 InGaAs와 GaAs 박막간 계면에 관한 연구)

  • Kim, Sam-Dong
    • Korean Journal of Materials Research
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    • 제6권1호
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    • pp.84-89
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    • 1996
  • 분자선 증착법(Molecular Beam Epitaxy)에 의하여 성장시킨 고농도 InGaAs layer에서 성장중지법이 계면 거칠기에 미치는 영향이 연구되었다. 계면을 평활화하기 위하여 단원자층의 GaAs 또는 AIAs를 InGaAs alyer 양쪽 계면에 증착한 뒤 뒤이어 성장중지를 실시하였다. Photoluminescence(PL) 측정에 의하면, 단원자 GaAs층 증착을 통한 평활화법보다 상당히 향상된 계면조건을 보여졌다. 고 분해능 단면 전자현미경법(Cross-section high resolution transmission electron microscopy, XHRTEM)에 의해 관찰되어진바, 계면 평활화법에 의해 계면의 평활성, 연속성 및 결정결함 밀도등에서 현저한 향상이 얻어졌다.

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A Study On Variance Estimation in Smoothing Goodness-of-Fit Tests (평활 적합도 검정에서의 분산추정의 영향)

  • Yoon, Yong-Hwa;Kim, Jong-Tae;Lee, Woo-Dong
    • Journal of the Korean Data and Information Science Society
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    • 제9권2호
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    • pp.189-202
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    • 1998
  • The goat of this paper is to study on variance estimation - Rice variance estimation, Gasser, Sroka and Jennen-Steinmetz's varince estimation - in smoothing goodness-of-fit tests. The comparisons of powers on test statistics are conducted by the change of variance, the number of oscillations, the amplitude of the alternative sample distribution.

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Preprocessing for performace improvement of Disparity Map Using Stereo Images (스테레오 영상의 변위 지도 성능 향상을 위한 전처리 과정 연구)

  • Cho, Myeongah;Kang, Hyeongseok;Kim, Seunghwan;Kang, Dongjin;Kim, Kyuheon
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 한국방송∙미디어공학회 2017년도 하계학술대회
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    • pp.117-120
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    • 2017
  • 본 논문은 스테레오 영상을 이용하여 3 차원 영상을 제공하기 위한 과정에서 중요한 변위 지도 생성 과정의 개선을 목적으로 한다. 변위 지도란, 서로 다른 시점의 두 영상 내에 매칭되는 대응점을 찾고 이와 같은 대응점들 간의 차를 통해 상대적 거리정보를 얻은 후, 이를 정규화하여 픽셀 값으로 나타낸 지도이다. 이에 본 논문에서는 변위 지도 생성 시, 물체들 간 대응점 매칭율을 높이기 위해 물체들의 외곽을 보존하여 형태를 뚜렷하게 하는 전처리 과정을 제안한다. 제안하는 방안은 제한 적응 히스토그램 평활화를 통해 물체들의 세부적인 특징들을 부각시키고, 양방향 필터를 통해 외각을 뚜렷하게 하는 전처리 과정을 포함한다. 본 논문에서는 제한 적응 히스토그램 평활화와 양방향 필터의 처리 과정을 분석하고, 실험결과를 통해 제안하는 전처리 과정을 검증하였다.

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Skin detection method based on local luminance and illumination revision in adult images (지역적인 밝기 정보와 조명 보정에 기반한 유해 영상에서의 피부색 검출 방법)

  • Park, Min Su;Park, Ki Tae;Moon, Young Shik
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 한국방송공학회 2011년도 하계학술대회
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    • pp.446-448
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    • 2011
  • 본 논문에서는 조명 보정과 지역적인 밝기 정보를 이용한 유해 영상에서의 피부색 검출 방법을 제안한다. 첫번째, 조명의 영향을 줄이기 위하여 입력 영상을 히스토그램 평활화하여 명암 값의 분포가 한쪽으로 치우치거나 균일하지 못한 영상의 명암 값 분포를 균일화 시켜 영상을 향상될 수 있도록 한다. 그 다음, 평활화 시킨 영상을 25 개의 블록으로 분할한 후, 각 블록에서의 밝기 값에 대한 통해 평균과 왜도를 구한다. 구해진 값들을 영상의 임계값으로 설정하여 이진화 시킨다. 그리고, 평활화시킨 영상의 RGB 값을 Lab 컬러 공간으로 변환한다. 변환된 컬러 공간내의 조명 성분 값인 L(Luminance)값을 추출하여 이를 역변환 한다. 역변환한 L 값은 비정규 조명을 갖는 유해 영상의 조명에 민감한 영향을 제거하기 위하여 평활화 영상에 합한다. 마지막으로, 밝기 임계값을 통해서 얻어진 이진영상내의 객체 영역과 RGB 피부색 임계값을 통한 조명 보정된 평활화 영상내의 피부색 영역의 공통된 영역을 결과값으로 추출한다.

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