• Title/Summary/Keyword: regularized

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Studies of Automatic Dental Cavity Detection System as an Auxiliary Tool for Diagnosis of Dental Caries in Digital X-ray Image (디지털 X-선 영상을 통한 치아우식증 진단 보조 시스템으로써 치아 와동 자동 검출 프로그램 연구)

  • Huh, Jangyong;Nam, Haewon;Kim, Juhae;Park, Jiman;Shin, Sukyoung;Lee, Rena
    • Progress in Medical Physics
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    • v.26 no.1
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    • pp.52-58
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    • 2015
  • The automated dental cavity detection program for a new concept intra-oral dental x-ray imaging device, an auxiliary diagnosis system, which is able to assist a dentist to identify dental caries in an early stage and to make an accurate diagnosis, was to be developed. The primary theory of the automatic dental cavity detection program is divided into two algorithms; one is an image segmentation skill to discriminate between a dental cavity and a normal tooth and the other is a computational method to analyze feature of an tooth image and take an advantage of it for detection of dental cavities. In the present study, it is, first, evaluated how accurately the DRLSE (Direct Regularized Level Set Evolution) method extracts demarcation surrounding the dental cavity. In order to evaluate the ability of the developed algorithm to automatically detect dental cavities, 7 tooth phantoms from incisor to molar were fabricated which contained a various form of cavities. Then, dental cavities in the tooth phantom images were analyzed with the developed algorithm. Except for two cavities whose contours were identified partially, the contours of 12 cavities were correctly discriminated by the automated dental caries detection program, which, consequently, proved the practical feasibility of the automatic dental lesion detection algorithm. However, an efficient and enhanced algorithm is required for its application to the actual dental diagnosis since shapes or conditions of the dental caries are different between individuals and complicated. In the future, the automatic dental cavity detection system will be improved adding pattern recognition or machine learning based algorithm which can deal with information of tooth status.

Utilizing Airborne LiDAR Data for Building Extraction and Superstructure Analysis for Modeling (항공 LiDAR 데이터를 이용한 건물추출과 상부구조물 특성분석 및 모델링)

  • Jung, Hyung-Sup;Lim, Sae-Bom;Lee, Dong-Cheon
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.26 no.3
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    • pp.227-239
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    • 2008
  • Processing LiDAR (Light Detection And Ranging) data obtained from ALS (Airborne Laser Scanning) systems mainly involves organization and segmentation of the data for 3D object modeling and mapping purposes. The ALS systems are viable and becoming more mature technology in various applications. ALS technology requires complex integration of optics, opto-mechanics and electronics in the multi-sensor components, Le. data captured from GPS, INS and laser scanner. In this study, digital image processing techniques mainly were implemented to gray level coded image of the LiDAR data for building extraction and superstructures segmentation. One of the advantages to use gray level image is easy to apply various existing digital image processing algorithms. Gridding and quantization of the raw LiDAR data into limited gray level might introduce smoothing effect and loss of the detail information. However, smoothed surface data that are more suitable for surface patch segmentation and modeling could be obtained by the quantization of the height values. The building boundaries were precisely extracted by the robust edge detection operator and regularized with shape constraints. As for segmentation of the roof structures, basically region growing based and gap filling segmentation methods were implemented. The results present that various image processing methods are applicable to extract buildings and to segment surface patches of the superstructures on the roofs. Finally, conceptual methodology for extracting characteristic information to reconstruct roof shapes was proposed. Statistical and geometric properties were utilized to segment and model superstructures. The simulation results show that segmentation of the roof surface patches and modeling were possible with the proposed method.

Trace Interpolation using Model-constrained Minimum Weighted Norm Interpolation (모델 제약조건이 적용된 MWNI (Minimum Weighted Norm Interpolation)를 이용한 트레이스 내삽)

  • Choi, Jihyun;Song, Youngseok;Choi, Jihun;Byun, Joongmoo;Seol, Soon Jee;Kim, Kiyoung;Lee, Jeongmo
    • Geophysics and Geophysical Exploration
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    • v.20 no.2
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    • pp.78-87
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    • 2017
  • For efficient data processing, trace interpolation and regularization techniques should be antecedently applied to the seismic data which were irregularly sampled with missing traces. Among many interpolation techniques, MWNI (Minimum Weighted Norm Interpolation) technique is one of the most versatile techniques and widely used to regularize seismic data because of easy extension to the high-order module and low computational cost. However, since it is difficult to interpolate spatially aliased data using this technique, model-constrained MWNI was suggested to compensate for this problem. In this paper, conventional MWNI and model-constrained MWNI modules have been developed in order to analyze their performance using synthetic data and validate the applicability to the field data. The result by using model-constrained MWNI was better in spatially aliased data. In order to verify the applicability to the field data, interpolation and regularization were performed for two field data sets, respectively. Firstly, the seismic data acquired in Ulleung Basin gas hydrate field was interpolated. Even though the data has very chaotic feature and complex structure due to the chimney, the developed module showed fairly good interpolation result. Secondly, very irregularly sampled and widely missing seismic data was regularized and the connectivity of events was quite improved. According to these experiments, we can confirm that the developed module can successfully interpolate and regularize the irregularly sampled field data.

Applications of Regularized Dequantizers for Compressed Images (압축된 영상에서 정규화 된 역양자화기의 응용)

  • Lee, Gun-Ho;Sung, Ju-Seung;Song, Moon-Ho
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.39 no.5
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    • pp.11-20
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    • 2002
  • Based on regularization principles, we propose a new dequantization scheme on DCT-based transform coding for reducing of blocking artifacts and minimizing the quantization error. The conventional image dequantization is simply to multiply the received quantized DCT coefficients by the quantization matrix. Therefore, for each DCT coefficients, we premise that the quantization noise is as large as half quantizer step size (in DCT domain). Our approach is based on basic constraint that quantization error is bounded to ${\pm}$(quantizer spacing/2) and at least there are not high frequency components corresponding to discontinuities across block boundaries of the images. Through regularization, our proposed dequantization scheme, sharply reduces blocking artifacts in decoded images. Our proposed algorithm guarantees that the dequantization process will map the quantized DCT coefficients will be evaluated against the standard JPEG, MPEG-1 and H.263 (with Annex J deblocking filter) decoding process. The experimental results will show visual improvements as well as numerical improvements in terms of the peak-signal-to-noise ratio (PSNR) and the blockiness measure (BM) to be defined.

A Study of Temporality of a Critical Discourse on the Modern in the Late Japanese Colonial Period (일제말기 근대비판 담론의 시간성 연구: 세계사·전통·비상시)

  • Ko, Bong-Jun
    • Cross-Cultural Studies
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    • v.23
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    • pp.33-55
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    • 2011
  • In the late Japanese colonial period, from the Sino-Japanese War until the Pacific War, critical discourses on the modern were prevalent in Japan and the Joseon. Despite the absence of a consensus about the specific definition of the modern, most thinkers agreed that the modern was something to be overcome. While some regarded naturalism and capitalism of the West as the essence of the modern, some others named scientism and humanism as the nature of the western modernity. Additionally, some criticized the temporal concept of historicism and brought new meanings of 'tradition' into relief, and some others advocated overcoming 'the West inherent in us'. This study is to consider the temporality of the theory of overcoming the modern focusing on the following three notions-world history, tradition, and emergency-, and examines the antinomy of them. The first notion to consider is 'world history'. The theorists of overcoming the modern, including the Kyoto school, discarded the progressive ideology that had led the Western modern history, and instead introduced 'world history' as a new notion. Although this resulted from the imperialistic embracement of the theories of Ranke, a major positivist historian from Germany, it contained antinomy of remaining in 'history' which was the modern temporal view. The second notion is 'tradition'. While the critical mind of 'world history' brought 'time of world' into question in the context of temporal realization, the notion of 'tradition' was to understand 'time of history' itself as the modern and overcome it. The critical mind of the notion involves the attempts to criticize regarding history as a 'progressive' process and to discover tradition as 'the present past' or 'the eternal present'. However, it also contained antinomy; the 'tradition' here was a notion that was created in the modern times, not passed down from ancient times. The third notion to consider is 'emergency', which was a method to define the present time as a transition period toward a new era, relating to states of war. However, the theorists of overcoming the modern did not regard 'emergency' as a particular time that strayed from normal states, instead they thought is as 'a regularized exceptional state', namely 'a state in which exceptions have become regulations'. However, the notion also contained antinomy since the word 'emergency' connotes abnormality.

Quality Visualization of Quality Metric Indicators based on Table Normalization of Static Code Building Information (정적 코드 내부 정보의 테이블 정규화를 통한 품질 메트릭 지표들의 가시화를 위한 추출 메커니즘)

  • Chansol Park;So Young Moon;R. Young Chul Kim
    • KIPS Transactions on Software and Data Engineering
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    • v.12 no.5
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    • pp.199-206
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    • 2023
  • The current software becomes the huge size of source codes. Therefore it is increasing the importance and necessity of static analysis for high-quality product. With static analysis of the code, it needs to identify the defect and complexity of the code. Through visualizing these problems, we make it guild for developers and stakeholders to understand these problems in the source codes. Our previous visualization research focused only on the process of storing information of the results of static analysis into the Database tables, querying the calculations for quality indicators (CK Metrics, Coupling, Number of function calls, Bad-smell), and then finally visualizing the extracted information. This approach has some limitations in that it takes a lot of time and space to analyze a code using information extracted from it through static analysis. That is since the tables are not normalized, it may occur to spend space and time when the tables(classes, functions, attributes, Etc.) are joined to extract information inside the code. To solve these problems, we propose a regularized design of the database tables, an extraction mechanism for quality metric indicators inside the code, and then a visualization with the extracted quality indicators on the code. Through this mechanism, we expect that the code visualization process will be optimized and that developers will be able to guide the modules that need refactoring. In the future, we will conduct learning of some parts of this process.

Jeongjo's Enjoyment of the Palace Garden (정조(正祖)의 궁원(宮苑) 유락(遊樂))

  • Hong, Hyoung-Soon
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.33 no.4
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    • pp.10-25
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    • 2015
  • The purpose of this research is to investigate the reality behind Jeongjo's enjoyment of the palace garden. If I were to summarize the results of this research, they are as follows: First, The 'Sanghwajoeoyeon(賞花釣魚宴)' has the differentiation which decided and regularized the rules and the regulations with the annual meetings for the Kyujanggak(奎章閣). Jeongjo had held the events five times. Second, The 'Seshimdae(洗心臺) Excursion' is based on the tragic personal history of Jeongjo. There were four events. Third, Jeongjo had enjoyed the 'viewing of the waterfall(觀瀑)' of the Okryucheon(玉流川) where a lot of the water overflows right after it rains. This is worth the special mention with regard to the point that it is a temporary landscape and not an usual landscape. Fourth, As an event for the military officers, the 'Seoljungryonghohwe(雪中龍虎會)' was held seven times. This event had been held in the middle of the winter. And each of the attendees skewered a pheasant and roasted and ate it. Also, it emphasized the sovereign and the subjects being the partners of the joys and the sorrows by giving the alcoholic drinks and the music. Fifth, Jeongjo had consoled the hard work by the civilian subjects either by holding the brazier feast(煖爐會) in the winter or by granting the alcoholic drinks and the foods according to the historical facts of the brazier feasts. Sixth, Jeongjo was good at archery and enjoyed it. During the period of his reign, Jeongjo held twice Yeonsarye(燕射禮). Seventh, Jeongjo soothed his desire to get out of the busy everyday life at the royal palace garden. While appreciating the natural landscape of the backyard, he was awakened of the meaning of the Book of Changes(周易) in which all the things had been created and changed. Eighth, At the royal palace garden, Jeongjo actively prepared the place for enjoyment by the sovereign and the subjects together. It is judged that this is because, in order to materialize his political ideals, the support by all the subjects who had been close was needed. The limitation of this research is the fact that the research had been proceeded with limited to the translations, among the many old writings related to Jeongjo. With the accumulation of the excavations of the new thoughts and of the results of the translations, the researches that are deeper will be needed.

Development of Regularized Expectation Maximization Algorithms for Fan-Beam SPECT Data (부채살 SPECT 데이터를 위한 정칙화된 기댓값 최대화 재구성기법 개발)

  • Kim, Soo-Mee;Lee, Jae-Sung;Lee, Soo-Jin;Kim, Kyeong-Min;Lee, Dong-Soo
    • The Korean Journal of Nuclear Medicine
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    • v.39 no.6
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    • pp.464-472
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    • 2005
  • Purpose: SPECT using a fan-beam collimator improves spatial resolution and sensitivity. For the reconstruction from fan-beam projections, it is necessary to implement direct fan-beam reconstruction methods without transforming the data into the parallel geometry. In this study, various fan-beam reconstruction algorithms were implemented and their performances were compared. Materials and Methods: The projector for fan-beam SPECT was implemented using a ray-tracing method. The direct reconstruction algorithms implemented for fan-beam projection data were FBP (filtered backprojection), EM (expectation maximization), OS-EM (ordered subsets EM) and MAP-EM OSL (maximum a posteriori EM using the one-step late method) with membrane and thin-plate models as priors. For comparison, the fan-beam protection data were also rebinned into the parallel data using various interpolation methods, such as the nearest neighbor, bilinear and bicubic interpolations, and reconstructed using the conventional EM algorithm for parallel data. Noiseless and noisy projection data from the digital Hoffman brain and Shepp/Logan phantoms were reconstructed using the above algorithms. The reconstructed images were compared in terms of a percent error metric. Results: for the fan-beam data with Poisson noise, the MAP-EM OSL algorithm with the thin-plate prior showed the best result in both percent error and stability. Bilinear interpolation was the most effective method for rebinning from the fan-beam to parallel geometry when the accuracy and computation load were considered. Direct fan-beam EM reconstructions were more accurate than the standard EM reconstructions obtained from rebinned parallel data. Conclusion: Direct fan-beam reconstruction algorithms were implemented, which provided significantly improved reconstructions.

Manufacturing Location and Linkages in the Suburb of Metropolitan Pusan (부산시 근교의 공업입지와 지역적 연계)

  • Lim, Yeong-Dae
    • Journal of the Korean association of regional geographers
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    • v.6 no.1
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    • pp.1-28
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    • 2000
  • The purpose of this study is to clarify the suburbanization of manufacturing, and location and linkages of decentralized manufacturing from Metropolitan Pusan by means of case study on manufacturing location and linkages in the suburb of Metropolitan Pusan. Kimhae city and Yangsan-Gun toward which heavy decentralization of manufacturing from the Metropolitan Pusan has been done. Both hard data and soft data were used as the basic data. Hard data are the statistical data in statistical yearbooks and firm list in directories. The former consists of the number of establishments and employees classified by product type, firm size and unit area. The latter consists of owner's names, addresses, employee number, products and headquarters of firms. Soft data are the results of the interviews with the 242 owners of firms in the four case study areas selected by Proportional Stratified Sampling Method. The major findings are as follows: 1. The spatial variations of manufacturing in the suburb was regularized in the latter half of 1970's. The primary processes to decentralize manufacturing from Metropolitan Pusan were the birth, relocation and establishment of branches of the firms. Among them the relocation of small outer-oriented single-location firms from Pusan was the most important. 2. The spatial variations undergoing spatial expansion of manufacturing distribution and increase of agglomeration degree of manufacturing, proceeded from the adjacents of Metropolitan Pusan to the outer areas along the main transportation route. 3. The main factors which caused manufacturing to decentralize from the Metropolitan Pusan were firm policy and land for this policy. The main locational factors which induced the decentralizing manufacturing into the suburb were land, market and transportation. 4. The strength of linkages with the outside of the study area is stronger than that of linkages with the inside. There is distance-decay-function in the strength of linkages with the outside, and linkages with short distant areas are stronger than those with long distant areas. 5. The ranges of spatial linkages in procurement of materials, in subcontraction and in marketing are wider than those in ordering. 6. The main factors which cause the formation of linkages are different by types of linkages: monopolistic and oligopolistic supply are important in procurement linkages; characteristics of products and the subsequent marketing difficulties, in subcontraction linkages; fluctuation, cost reduction, insufficient facility and characteristics of products, in ordering linkages; subcontract, characteristics of product and the subsequent marketing difficulties, in marketing linkages. 7. The changes of linkages owing to locational changes of firms were great, and were greater in long distant areas than in short distant areas. 8. The main factor influencing on the changes of linkages was the easiness in the transportation of goods, movement of labour and contacts with customers. In conclusion, some facts described above were proved to be consistent with the results of proceeding studies in the other areas: influence of relocation of decentralizing firms on the suburbanization; the factors of manufacturing decentralization; spatial characteristics of linkages; linkage changes owing to relocation of firms. Some were proved to be partly consistent: locational factors inducing decentralized manufacturing into the suburb were proved to be inconsistent. I think that the results of previous studies on the other areas can be applicable to the explanation on the decentralization of Metropolitan manufacturing from the viewpoint of the suburb. For the better explanation on the decentralization of Metropolitan manufacturing, more empirical case studies on the suburbanization of manufacturing are necessary.

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Location and Linkages of Manufacturing in Jangyu-Myun, Kimhae-Gun (김해군 장유면의 공업입지와 지역적 연계)

  • Lim, Yeong-Dae
    • Journal of the Korean association of regional geographers
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    • v.4 no.1
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    • pp.99-120
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    • 1998
  • The purpose of this study is to clarify the industrialization process, and locational factors and linkages of manufacturing in Jangyu-Myun, a suburb of Metropolitan Pusan, toward which heavy decentralization of manufacturing from Pusan has been done. Hard data and soft data were used as the basic data. Hard data used for this study were both the statistical data which consists of the number of establishments and employee classified by product type, firm size, organizational type and unit area(dong) which were listed in statistics yearbooks, and the list of the owner's names, addresses, employee number, products and headquarters of firms which were listed in firm directories. Soft data were the results of the interviews with the 53 owners of firms surveyed among the firms selected by Proportional Stratified Sampling Method. The major findings were as follows: (1) Manufacturing location in Jangyu-Myun was regularized in 1980's in which decentralization of manufacturing was activiated. Though the industrialization of study area resulted from the birth, relocation and establishment of branches of the firms originated from the other regions, the relocation of small outer-oriented firms from the central city was the most important factor among them. (2) The main locational factors which induced the decentralizing manufacturing from the central city into Jangyu-Myun are closely related to land, transportation, personal factor, raw material suppliers and market. (3) The differences of important locational factors by the size and organizational type of firms are relevant to the characteristics of manufacturing location. (4) The changes of linkages attendant upon locational changes of firms were not so great and were localized in labor supply and marketing. (5) The strength of linkages is strong in the procurement of materials, in the subcontraction and in the marketing, but not in the ordering. (6) The main factors influencing on the formation of linkages are different by the types of linkages: monopolistic and oligopolistic supply are important in procurement linkages; characteristics of products and production capacity in the subcontraction and ordering; characteristics of products and the subsequent difficulties, in the marketing. (7) With the exception of procurement linkages, the strength of linkages with the outside of the study area are stronger than the linkages with the inside. The strength of linkages with the outside has distance-decay-function and strong linkages with the central city. (8) These spatial characteristics of linkages are different by products type, firm size and organizational type of firms: the spatial ranges of linkages are wider in the multi-location firms than in the single-location firms; the larger the firm size, the wider the spatial range of linkages: there is no consistent trend by products type. In conclusion, some facts described above were proved to be consistent with the results of proceeding studies in the other areas: influence of central city manufacturing relocation on industrialization in the suburb: different decentralization by products type, firm size and organizational types of firms: different locational factors by products type, firm size and organizational types of firms; linkage changes attendant upon locational changes of firms; spatial differences of linkages by products type, firm size and organizational type of firms. Some other factors were proved to be partly consistent: locational factors and spatial characteristics of linkages. Accordingly I think that the results of previous studies on the other areas can be applicable to the explanation of the location and linkage of manufacturing in Jangyu-Myun. For the better explanation on the characteristics of manufacturing decentralization from the central city, more empirical case studies on the location and linkage of manufacturing in the suburb areas are necessary.

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