• Title/Summary/Keyword: region contrast

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Analysis of Camera Rotation Using Three Symmetric Motion Vectors in Video Sequence (동영상에서의 세 대칭적 움직임벡터를 이용한 카메라 회전각 분석)

  • 문성헌;박영민;윤영우
    • Journal of the Institute of Convergence Signal Processing
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    • v.3 no.2
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    • pp.7-14
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    • 2002
  • This paper proposes a camera motion estimation technique using special relations of motion vectors of geometrically symmetrical triple points of two consecutive views of single camera. The proposed technique uses camera-induced motion vectors and their relations other than feature points and epioplar constraints. As contrast to the time consuming iterations or numerical methods in the calculation of E-matrix or F-matrix induced by epipolar constraints, the proposed technique calculates camera motion parameters such as panning, tilting, rolling, and zooming at once by applying the proposed linear equation sets to the motion vectors. And by devised background discriminants, it effectively reflects only the background region into the calculation of motion parameters, thus making the calculation more accurate and fast enough to accommodate MPEG-4 requirements. Experimental results on various types of sequences show the validity and the broad applicability of the proposed technique.

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AN EXPERIMENTAL STUDY FOR ESTABLISHMENT OF ORTHOTOPIC SALIVARY TUMOR MODELS IN MICE (마우스에서 타액선암 동위종양 모델 제작을 위한 실험적 연구)

  • Park, Young-Wook;Chung, Seong-Hoon
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.33 no.2
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    • pp.81-93
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    • 2007
  • Purpose: Adenoid cystic carcinoma (ACC) is a relatively rare tumor that arises in glandular tissues of the head and neck region and sometimes has a protracted clinical course with perineural invasion and delayed onset of distant lung metastasis. Treatment failure of salivary ACC is most often associated with perineural and hematogenous tumor spread. However, very little has been known about the cellular and molecular mechanisms of perineural invasion and hematogenous distant metastasis of parotid ACC. This study was designed to develop an orthotopic tumor model of parotid adenoid cystic carcinoma in athymic nude mice. Experimental Design: A melanoma cell line was injected into the parotid gland of athymic mice to determine whether such implantation was technically feasible. A parotid ACC cell line was then injected into the parotid gland or the subcutaneous tissue of athymic mice at various concentrations of tumor cells, and the mice were thereafter followed for development of tumor nodule. The tumors were examined histopathologically for perineural invasion or regional or distant lung metastasis. We used an oral squmous cell carcinoma cell line as control. Results: Implantation of tumor(melanoma) cell suspension into the parotid gland of nude mice was technically feasible and resulted in the formation of parotid tumors. A parotid ACC cell line, ACC3 showed no significantly higher tumorigenicity, but showed significantly higher lung metastatic potential in the parotid gland than in the subcutis. In contrast, mucosal squmous cell carcinoma cell line doesn’t show significantly higher lung metastatic potential in the parotid gland than in the subcutis. The ACC tumor established in the parotid gland seemed to demonstrate perineural invasion of facial nerve, needs further study. Conclusion: An orthotopic tumor model of salivary ACC in athymic nude mice was successfully developed that closely recapitulates the clinical situations of human salivary ACC. This model should facilitate the understanding of the cellular and molecular mechanisms of tumorigenisis and metastasis of salivary ACC and aid in the development of targeted molecular therapies of salivary ACC.

ADENOMATOID ODONTOGENIC TUMOR ASSOCIATED WITH AN IMPACTED MANDIBULAR RIGHT LATERAL INCISOR (하악 우측 측절치에 발생한 선양 치성 종양)

  • Park, Mi-Seon;Park, Ho-Won;Lee, Ju-Hyun;Seo, Hyun-Woo
    • Journal of the korean academy of Pediatric Dentistry
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    • v.38 no.4
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    • pp.407-412
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    • 2011
  • Adenomatoid odontogenic tumor(AOT) is an infrequent odontogenic tumor which arise in the jaw. It was considered as a variant of ameloblastoma. The adenomatoid odontogenic tumor is clearly benign and, in contrast to the ameloblastoma, present a very low recurrence. It most often appears in the canine region of the maxilla. The adenomatoid odontogenic tumor is frequently asymptomatic, however it may cause painless swelling. The radiological findings of adenomatoid odontogenic tumor frequently share characteristics of dentigerous cyst and unicystic ameloblastoma. Conservative surgical enucleation and curettage are the treatment of choice. In this case a 10-year-old child was presented with mandibular right lateral incisor in unerupted. Radiographically, the tooth was impacted and a radiolucency was seen in the area. The lesion was enuclated without extraction of the tooth. Bracket was attached on the tooth for orthodontic extrusion installed. Histopathologically adenomatoid odontogenic tumor was revealed.

Rpi-blb2 Gene-Mediated Late Blight Resistance in Plants

  • Oh, Sang-Keun
    • 한국균학회소식:학술대회논문집
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    • 2015.11a
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    • pp.26-26
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    • 2015
  • Phytophthora infestans is the causal agent of potato and tomato late blight, one of the most devastating plant diseases. P. infestans secretes effector proteins that are both modulators and targets of host plant immunity. Among these are the so-called RXLR effectors that function inside plant cells and are characterized by a conserved motif following the N-terminal signal peptide. In contrast, the effector activity is encoded by the C terminal region that follows the RXLR domain. Recently, I performed in planta functional profiling of different RXLR effector alleles. These genes were amplified from a variety of P. infestans isolates and cloned into a Potato virus X (PVX) vector for transient in planta expression. I assayed for R-gene specific induction of hypersensitive cell death. The findings included the discovery of new effector with avirulence activity towards the Solanum bulbocastanum Rpi-blb2 resistance gene. The Rpi-blb2 encodes a protein with a putative CC-NBS-LRR (a coiled-coil-nucleotide binding site and leucine-rich repeat) motif that confers Phytophthora late blight disease resistance. We examined the components required for Rpi-blb2-mediated resistance to P. infestans in Nicotiana benthamiana. Virus-induced gene silencing was used to repress candidate genes in N. benthamiana and to assay against P. infestans infections. NbSGT1 was required for disease resistance to P. infestans and hypersensitive responses (HRs) triggered by co-expression of AVRblb2 and Rpi-blb2 in N. benthamiana. RAR1 and HSP90 did not affect disease resistance or HRs in Rpi-blb2-transgenic plants. To elucidate the role of salicylic acid (SA) in Rpi-blb2-mediated resistance, we analyzed the response of NahG-transgenic plants following P. infestans infection. The increased susceptibility of Rpi-blb2-transgenic plants in the NahG background correlated with reduced SA and SA glucoside levels. Furthermore, Rpi-blb2-mediated HR cell death was associated with $H_2O_2$, but not SA, accumulation. SA affects basal defense and Rpi-blb2-mediated resistance against P. infestans. These findings provide evidence about the roles of SGT1 and SA signaling in Rpi-blb2-mediated resistance against P. infestans.

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Effect of Ga Addition on the Electrical and Structural Properties of (Zn,Mg)O Transparent Electrode Films (Ga 첨가량이 (Zn,Mg)O 투명전극 막의 전기적, 결정학적 특성에 미치는 영향)

  • Suh, Kwang-Jong;Wakahara, Akihiro;Yoshida, Akira
    • Korean Journal of Materials Research
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    • v.15 no.8
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    • pp.491-495
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    • 2005
  • (Zn,Mg)O (ZMO) thin films doped with Ga $(0\~0.03mol\%)$ in the target source were prepared by pulsed laser deposition on c-plane sapphire substrates at $500^{\circ}C$, and the effect of Ga contents on the properties of the electrical, optical and crystal properties of the deposited films was investigated. From X-ray diffraction patterns, ZMO film doped with $0.02 mol\%$ Ga showed crystal structure with c-axis preferred orientation, showing only the (0002) and (0004) diffraction peaks. In contrast, ZMO film doped with $Ga=0.03 mol\%$ showed a randomly oriented crystal structure. All the samples were highly transparent, showing the transmittance values of above $85\%$ in the visible region. For all the Ga doped ZMO films, the value of energy band gap was found to be about 3.5 eV, regardless of their Ga contents. From the Hall measurements, the resistivity and the carrier density for the ZMO film doped with $0.01 mol\%$ Ga were about $5\times10^{-4}\Omega-cm$ and $2\times10^{21}cm^{-3}$, respectively.

Soft Tissue Fibroma in Two Dogs (개에서 발생한 연부조직 섬유종 2례)

  • Choi, Ho-Jung;Lee, Jung-Woo;An, Ji-Young;O, I-Se;Ahn, Se-Joon;Jeong, Seong-Mok;Park, Seong-Jun;Cho, Sung-Whan;Lee, Young-Won
    • Journal of Veterinary Clinics
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    • v.25 no.5
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    • pp.424-428
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    • 2008
  • A 10-year-old castrated male Schnauzer (case 1) and a 13-year-old intact male Schnauzer (case 2) was referred with mass of left hind limb. We performed hemogram, serum chemistry, radiography, ultrasonography, computed tomography, fine needle aspiration and histopathology. The complete blood counts and serum biochemistry results were within the reference range. Radiography showed cutaneous mass with soft tissue density. The lesions of two dogs were revealed a definite marginated hyperechoic mass with vascularization in ultrasonography. Computed tomography showed an isodense mass in the left hind limb region with minimal contrast enhancing in case 1 and heterogenous enhancement in case 2. Cytology from ultrasonographic guided aspiration of the mass was suspected fibrous tissue-derived benign cell in two dogs. A surgical excision was performed in two dogs. In histological examination of the resected mass, cutaneous fibroma was revealed. The two patients were successfully treated by surgery and postoperative care. This report decribes and compares radiographic, ultrasonographic, computed tomographic, cytologic and histopathologic features of the cutaneous fibroma of two schnauzer dogs.

Widespread Occurrence of Small Inversions in the Chloroplast Genomes of Land Plants

  • Kim, Ki-Joong;Lee, Hae-Lim
    • Molecules and Cells
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    • v.19 no.1
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    • pp.104-113
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    • 2005
  • Large inversions are well characterized in the chloroplast genomes of land plants. In contrast, reports of small inversions are rare and involve limited plant groups. In this study, we report the widespread occurrence of small inversions ranging from 5 to 50 bp in fully and partially sequenced chloroplast genomes of both monocots and dicots. We found that small inversions were much more common than large inversions. The small inversions were scattered over the chloroplast genome including the IR, SSC, and LSC regions. Several small inversions were uncovered in chloroplast genomes even though they shared the same overall gene order. The majority of these small inversions were located within 100 bp downstream of the 3' ends of genes. All had inverted repeat sequences, ranging from 11 to 24 bp, at their ends. Such small inversions form stem-loop hairpin structures that usually have the function of stabilizing the corresponding mRNA molecules. Intra-molecular recombination between the inverted sequences in the stem-forming regions are responsible for generating flip-flop orientations of the loops. The presence of two different orientations of the stem-loop in the trnL-F noncoding region of a single species of Jasminum elegans suggests that a short inversion can be generated within a short period of time. Small inversions of non-coding sequences may influence sequence alignment and character interpretation in phylogeny reconstructions, as shown in nine species of Jasminum. Many small inversions may have been generated by parallel or back mutation events during chloroplast genome evolution. Our data indicate that caution is needed when using chloroplast non-coding sequences for phylogenetic analysis.

Characteristics of Atmospheric Aerosol Optical Thickness over the Northeast Asia Using TERRA/MODIS Data during the Year 2000~2005 (동북아시아 지역에서 TERRA/MODIS 위성자료를 이용한 2000~2005년 동안의 대기 에어러솔 광학두께 변화 특성)

  • Lee, Dong Ha;Lee, Kwon Ho;Kim, Jeong Eun;Kim, Young Joon
    • Atmosphere
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    • v.16 no.2
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    • pp.85-96
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    • 2006
  • The six-year (2000~2005) record of aerosol optical thickness (AOT or $\tau$) data from the Moderate Resolution Imaging Spectroradiometer (MODIS) was analyzed over the Northeast Asia. The MODIS AOT standard products (MOD04_L2) over both ocean and land were collected to evaluate the spatial and temporal variability of the atmospheric aerosols over the study region ($32^{\circ}N{\sim}42^{\circ}N$ and $115^{\circ}E{\sim}133^{\circ}E$). The monthly averaged AOT result revealed slight changes(${\pm}0.002{\tau}/month$), which was almost unchangeable, over Korea. In contrast, the large AOT values (> 0.6) and a significant AOT increase (> 0.004 ${\tau}/month$) over East China were observed. For the analysis of spatio-temporal variability of AOT values, study area was divided by six sectors (I: North-East China, II: East China, III: Yellow Sea, IV: Korea Peninsular, V: East Sea, and VI: South Sea and Western part of Japan). The considerable result showed that particularly high AOT contribution was observed over sector I (32.5%) and II (25.5%) where some major urban and industrialized areas and agricultural fields are located and other cases were observed 13.2%, 14.6%, 7.1%, 7.0% over sector III, IV, V, and VI, respectively. In addition, yearly AOT changes based on seasons are observed differently at each sector but increasing trends reveal in summer and fall over all sectors.

Extraction of the aquaculture farms information from the Landsat- TM imagery of the Younggwang coastal area

  • Shanmugam, P.;Ahn, Yu-Hwan;Yoo, Hong-Ryong
    • Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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    • 2004.03a
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    • pp.493-498
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    • 2004
  • The objective of the present study is to compare various conventional and recently evolved satellite image-processing techniques and to ascertain the best possible technique that can identify and position of aquaculture farms accurately in and around the Younggwang coastal area. Several conventional techniques performed to extract such information fiom the Landsat-TM imagery do not seem to yield better information about the aquaculture farms, and lead to misclassification. The large errors between the actual and extracted aquaculture farm information are due to existence of spectral confusion and inadequate spatial resolution of the sensor. This leads to possible occurrence of mixture pixels or 'mixels' of the source of errors in the classification techniques. Understanding the confusing and mixture pixel problems requires the development of efficient methods that can enable more reliable extraction of aquaculture farm information. Thus, the more recently evolved methods such as the step-by-step partial spectral end-member extraction and linear spectral unmixing methods are introduced. The farmer one assumes that an end-member, which is often referred to as 'spectrally pure signature' of a target feature, does not appear to be a spectrally pure form, but always mix with the other features at certain proportions. The assumption of the linear spectral unmxing is that the measured reflectance of a pixel is the linear sum of the reflectance of the mixture components that make up that pixel. The classification accuracy of the step-by-step partial end-member extraction improved significantly compared to that obtained from the traditional supervised classifiers. However, this method did not distinguish the aquaculture ponds and non-aquaculture ponds within the region of the aquaculture farming areas. In contrast, the linear spectral unmixing model produced a set of fraction images for the aquaculture, water and soil. Of these, the aquaculture fraction yields good estimates about the proportion of the aquaculture farm in each pixel. The acquired proportion was compared with the values of NDVI and both are positively correlated (R$^2$ =0.91), indicating the reliability of the sub-pixel classification.ixel classification.

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Detection of Visual Attended Regions in Road Images for Assisting Safety Driving (안전 운전 지원을 위한 도로 영상에서 시각 주의 영역 검출)

  • Kim, Jong-Bae
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.49 no.1
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    • pp.94-102
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    • 2012
  • Recently entered into an aging socity as the number of elderly drivers is increasing. Traffic accidents of elderly drivers are caused by driver inattentions such as poor vehicle control due to aging, visual information retrieval problems caused by presbyopia, and objects identifying problems caused by low contrast sensitivity. In this paper, detection method of ROIs on the road is proposed. The proposed method creates the saliency map to detect the candidate ROIs from the input image. And, the input image is segmented to obtain the ROIs boundary. Finally, selective visual attention regions are detected according to the presence or absence of a segmented region with saliency pixels. Experimental results from a variety of outdoor environmental conditions, the proposed method presented a fast object detection and a high detection rate.