• Title/Summary/Keyword: 불연속성

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Photometry Data Compression for Three-dimensional Mesh Models Using Connectivity and Geometry Information (연결성 정보와 기하학 정보를 이용한 삼차원 메쉬 모델의 광학성 정보 압축 방법)

  • Yoon, Young-Suk;Ho, Yo-Sung
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.45 no.3
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    • pp.160-174
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    • 2008
  • In this paper, we propose new coding techniques for photometry data of three-dimensional(3-D) mesh models. We make a good use of geometry and connectivity information to improve coding efficiency of color, normal vector, and texture data. First of all, we determine the coding order of photometry data exploiting connectivity information. Then, we exploit the obtained geometry information of neighboring vortices through the previous process to predict the photometry data. For color coding, the predicted color of the current vertex is computed by a weighted sum of colors for adjacent vortices considering geometrical characteristics between the current vortex and the adjacent vortices at the geometry predictor. For normal vector coding, the normal vector of the current vertex is equal to one of the optimal plane produced by the optimal plane generator with distance equalizer owing to the property of an isosceles triangle. For texture coding, our proposed method removes discontinuity in the texture coordinates and reallocates texture image segments according to the coding order. Simulation results show that the proposed compression schemes provide improved performance over previous works for various 3-D mesh models.

The Strategic Research Approach for the Grand Plan of the Korean Peninsula Infrastructure (통일한반도 국토인프라 Grand Plan 연구 구상)

  • Lee, Bok-Nam
    • Land and Housing Review
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    • v.6 no.2
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    • pp.43-48
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    • 2015
  • Right after president Keun-Hae Park's announcement at German Dresden on March 2014, both expectation and skepticism have been raised for the Korean unification. The unification would give a great chance for the economic prosperity in the positive sense. In the negative sense, it would only give a great burden to the Republic's financial status. Comparing the expectation of the unification, there are lack of structured preparation, duplicated and/or overlapped systematic approach, and even the national strategies are diffused. There are several individual research papers, analytical data and information, researches on the industry and technology. However most of the previous researches and findings are unstructured and lack of completeness. It is hard to find out the overall feature of the unification strategy. West German has compassed that it knew very few the reality of East German status. The Korean Government may know much less about North Korea's condition comparing to West German. Before the actual unification in the Korean peninsula, it needs the Grand Plan for the national infrastructure and land utilization of the Korean peninsula. During the development of the Grand Plan for the Korean peninsula, the Asian Global transportation network could be developed at the same time. The German's unification experience can give a great opportunity to the development of the Gran Plan. The data and information, and the previous researches should be classified and structured in a way of systematic arrangement. Since most of investment and budget for the unification come from the Korea, it would be very much beneficial for the Korean people. The openness and early exposures of the Grand Plan for the national infrastructure are considered as mandatory action.

The Characteristic and genesis of Polysequum Soils in Jeju (Polysequum토양(土壤)의 특성(特性) 및 생성(生成)에 관(關)한 연구(硏究))

  • Shin, Jae-Sung;Jung, Pil-Gyun;Um, Ki-Tae
    • Korean Journal of Soil Science and Fertilizer
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    • v.9 no.2
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    • pp.93-98
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    • 1976
  • The present paper is a part of a study aimed at gaining information on the origin, mode of deposition, and characteristics of volcanic soils in Jeju. Volcanic activity of Jeju island has extremely influenced on the formation of various soils. Polysequum phenomenon of soils is one of outstanding soil genesis in Jeju. The typical polysequum soils was collected and analyzed by morphological, physico-chemical, mineralogical and micromorphological approaches The results are as follows: 1. The soils consists of polysequa, A and B horizons from volcanic ashes, unconsolidated volcanic sand layer and B(I) horizons from residual basalts. 2. The lithological discontinuity is also very distinct; silt loam from volcanic ashes, sand (II) from volcanic sand and clayey (III) from basalts. 3. Volcanic sand layer seems to be influenced by lava flow. The properties of it are similar to volcanic ashes rather than beneath residuum in micromorphological aspects. In micromorphological, this layer is gradually changed into soils. 4. Dominant clay minerals are allophane in A and B horizons from volcanic ashes and kaoline, vermiculite and illite from residual basalts. 5. The soils are not developed. There is no formation of argillic horizon in subsurface layers.

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A Novel Rate Control for Improving the QoE of Multimedia Streaming Service in the Internet Congestion (인터넷 혼잡상황에서 멀티미디어 스트리밍 서비스의 QoE 향상을 위한 전송률 제어기법)

  • Koo, Ja-Hon;Chung, Kwang-Sue
    • Journal of KIISE:Information Networking
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    • v.36 no.6
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    • pp.492-504
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    • 2009
  • The delivery of multimedia that efficiently adapts its bit-rate to changing network characteristics and conditions is one of the important challenging tasks in the design of today's real-time multimedia streaming systems such as IPTV, Mobile IPTV and so on. In these work, the primary focus is on network congestion, to improve network stability and inter-protocol fairness. However, these existing works have problems which do not support QoE (Quality of Experience), because they did not consider essential characteristics of contents playback such as the media continuity. In this paper, we propose a novel rate control scheme for improving the QoE of multimedia streaming service in the Internet congestion, called NCAR (Network and Client-Aware Rate control), which is based on network-aware congestion control and client-aware flow control scheme. Network-aware congestion control of the NCAR offers an improving reliability and fairness of multimedia streaming, and reduces the rate oscillation as well as keeping high link utilization. Client-aware flow control of NCAR offers a removing the media discontinuity and a suitable receiver buffer allocation, and provides a good combination of low playback delay. Simulation results demonstrate the effectiveness of our proposed schemes.

Benign Tumor-Like Developmental Salivary Gland Defect (양성 종양과 유사한 형태를 가진 발육성 타액선 골결손)

  • An, Seo-Young;Kim, Yong-Gun;Jung, Jae-Kwang
    • Journal of Dental Rehabilitation and Applied Science
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    • v.28 no.3
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    • pp.301-307
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    • 2012
  • 50-year-old female and 50-year-old male were referred to the department of the oral and maxillofacial surgery of Kyungpook national university dental hospital with asymptomatic lesions on their posterior mandibular body areas. They were discovered incidentally on panoramic radiographs during routine dental examination. Physical examination revealed no remarkable findings. Each panoramic radiograph showed well defined radiolucent lesions without hyperostotic border on their posterior mandibular body area. At first they were diagnosed as benign tumors because they looked like multilocular pattern and one of the patient showed discontinuity of mandibular canal within the lesion. CT scans demonstrated well demarcated and irregular lingual depression filled with fat tissue and they were diagnosed as developmental salivary gland defects. One of the lesion showed no change on follow-up panoramic radiograph after 4 months. Developmental salivary gland defects resembling benign tumor are atypical cases and it is suggested that confirmatory imaging using CT or MRI should be taken.

Multitoning Method Based on Arrangement of Ink Distribution for Smooth Tone Transition (부드러운 계조 변화를 위한 잉크 분포 조절 기반의 멀티토닝 방법)

  • Park, Tae-Yong;Park, Kee-Hyon;Ha, Yeong-Ho
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.44 no.4 s.316
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    • pp.17-25
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    • 2007
  • Multilevel inkjet printer employs multiple ink droplets with variable dot size and/or different concentrations intended to preserve high fidelity color reproduction and the appearance of continuous tone. A variety of research efforts on multitoning techniques has progressed toward better image quality. However, banding artifacts appear due to the same dot distributions near the printable output levels. This results in discontinuity and visually unpleasing output, especially at the smooth tone transition region. In this paper, to reduce the banding artifacts, a multitoning method to arrange ink distribution by controlling the blending proportion of adjacent output pixels based on an improved threshold scaling function is proposed. Ink distributions across the banding regions are changed according to two factors of the threshold scaling function because these factors handle the blending point of adjacent output pixel. Therefore, 8 observers, subjectively investigated ink distributions around the printable output levels for a set of the improved threshold scaling function. For a threshold scaling function with the specific factor values, we can achieve smoother visual transition. In the experiment, the proposed method showed a reduction of banding artifacts in both u-ay and color image and represented better Performance of color reproduction.

Evaluation of an Effective Load Transfer System Applied to a Simple Model of a Wall Frame Structural System (단순 모델을 사용한 추상복합 건물의 효율적인 전이 시스템에 관한 연구)

  • 정영일;윤석한;홍원기;김희철
    • Journal of the Earthquake Engineering Society of Korea
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    • v.6 no.3
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    • pp.23-29
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    • 2002
  • A wall-frame type structural system has been widely used to make full use of a limited land in large cities to satisfy the several functional requirement in one building. However, this type of hybrid structure brought some problems due to the vertical discontinuity of a structural system. The response of a wall-frame type structural system having a deep transfer girder was observed. An arch system was introduced to replace the deep transfer girder. The adequacy of an arch system was observed for the various boundary conditions of a system. The proposed system was compared to a general transfer girder system by applying both gravity load and lateral load. It was observed that an arch system fairly distributes the stress without concentrating stress at a certain location of a system differently from the current transfer girder system. The moment decrement effect of a column can also be obtained by eliminating the large mass of a transfer girder. Also it was investigated that an arch system is more economical and effective than the current transfer girder system.

A Hippocampus Segmentation in Brain MR Images using Level-Set Method (레벨 셋 방법을 이용한 뇌 MR 영상에서 해마영역 분할)

  • Lee, Young-Seung;Choi, Heung-Kook
    • Journal of Korea Multimedia Society
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    • v.15 no.9
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    • pp.1075-1085
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    • 2012
  • In clinical research using medical images, the image segmentation is one of the most important processes. Especially, the hippocampal atrophy is helpful for the clinical Alzheimer diagnosis as a specific marker of the progress of Alzheimer. In order to measure hippocampus volume exactly, segmentation of the hippocampus is essential. However, the hippocampus has some features like relatively low contrast, low signal-to-noise ratio, discreted boundary in MRI images, and these features make it difficult to segment hippocampus. To solve this problem, firstly, We selected region of interest from an experiment image, subtracted a original image from the negative image of the original image, enhanced contrast, and applied anisotropic diffusion filtering and gaussian filtering as preprocessing. Finally, We performed an image segmentation using two level set methods. Through a variety of approaches for the validation of proposed hippocampus segmentation method, We confirmed that our proposed method improved the rate and accuracy of the segmentation. Consequently, the proposed method is suitable for segmentation of the area which has similar features with the hippocampus. We believe that our method has great potential if successfully combined with other research findings.

A Comparison of Accuracy between MRI and Arthroscopic Finding in the Diagnosis of Acute ACL Tear (급성 전방십자인대 손상의 진단에 있어 관절경 소견과의 비교분석을 통한 자기공명영상의 유용성)

  • Choi, Chong-Hyuk;Yoon, Han-Kook;Kim, Bo-Ram;Yoon, Choon-Sik
    • Journal of the Korean Arthroscopy Society
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    • v.9 no.1
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    • pp.46-50
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    • 2005
  • Purpose: The purpose of this study is to evaluate the accuracy of magnetic resonance imaging (MRI) in the diagnosis of acute anterior cruciate ligament (ACL) injury and its tear pattern in comparison with arthroscopic finding. Materials and Methods: Sixty consecutive patients with acute ACL injury were taken NRI followed by arthroscopic examination between January 2002 and June 2004. MRI findings were reviewed according to the presence of ACL discontinuity, diffuse swelling or thickening, focal edema, collapse on distal end, and any combined tear. The pathologic findings were then confirmed arthroscopically. The diagnostic accuracy of MRI on ACL tear pattern was analyzed by obtaining its positive predictive value. Results: All fifty two cases with presence of discontinuity on MRI showed ACL rupture arthroscopically. The location of ACL tear, diffuse swelling and focal edema on MRI also corresponded with arthroscopic findings respectively. However, the diagnostic accuracy of MRI was relatively lower in the presence of other ACL patterns such as collapses and combined tear. Conclusion: Preoperative MRI findings seem to be in accordance with arthroscopic findings and is significantly accurate in detection of location and diffuse swelling and focal edema of ACL tear.

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Program Design and Implementation for Efficient Application of Heterogeneous Spatial Data Using GMLJP2 Image Compression Technique (GMLJP2 영상압축 기술을 이용한 다양한 공간자료의 효율적인 활용을 위한 프로그램 설계 및 구현)

  • Kim, Yoon-Hyung;Yom, Jae-Hong;Lee, Dong-Cheon
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.24 no.5
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    • pp.379-387
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    • 2006
  • The real world is spatially modelled conceptually either as discrete objects or earth surface. The generated data models are then usually represented as vector and raster respectively. Although there are limited cases where only one data model is sufficient to solve the spatial problem at hand, it is now generally accepted that GIS should be able to handle various types of data model. Recent advances in spatial technology introduced even more variety of heterogeneous data models and the need is ever growing to handle and manage efficiently these large variety of spatial data. The OGC (Open GIS Consortium), an international organization pursuing standardization in the geospatial industry. recently introduced the GMLJP2 (Geographic Mark-Up Language JP2) format which enables store and handle heterogeneous spatial data. The GMLJP2 format, which is based on the JP2 format which is an abbreviation for JPEG2000 wavelet image compression format, takes advantage of the versatility of the GML capabilities to add extra data on top of the compressed image. This study takes a close look into the GMLJP2 format to analyse and exploit its potential to handle and mange hetergeneous spatial data. Aerial image, digital map and LIDAR data were successfully transformed end archived into a single GMLJP2 file. A simple viewing program was made to view the heterogeneous spatial data from this single file.