• The Journal of Korean Institute of Communications and Information Sciences
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• v.26 no.11C
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• pp.85-93
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• 2001

In this paper, a path restoration method independent of failure location in all-optical networks is proposed and its wavelength requirements are calculated. In the proposed method, since a single backup wavelength is used for any link failure, a node can consist of only fixed wavelength transmitters, resulting in the levels node cost. Hence, restoration process can be triggered just after the failure detection, if combined with edge-disjoint path restoration method. This feature and the parallel cross-connection message transfer technique proposed in this paper make the restoration process faster. Also, it is shown the wavelength requirements in the proposed method are similar to the ones in the method using tunable backup wavelength, resulting in little increment for transmission cost.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.50 no.12
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• pp.575-583
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• 2001

Dynamic Voltage Restorer(DVR) which is installed between the supply and a critical load can restore voltage disturbances in distribution system. The restoration is based on injecting the same voltages as voltage sags. The ideal restoration is compensation to make the load voltages be unchanged. But voltage restoration involves real power or energy injection and the capability of energy storage is limited. So it must be considered how injection energy can be minimized and voltages can be made close to the voltages before fault. This paper describes conventional restoration techniques, which draw minimum energy from the DVR in order to correct a given voltage sag or swell. And this paper proposes a new concept of restoration technique to inject minimum energy. The proposed method is based on the definition of voltage tolerance in load side. Hence using the proposed method a particular disturbance can be corrected with less amount of storage energy compared to those of conventional methods.

• Korean Journal of Remote Sensing
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• v.19 no.6
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• pp.479-490
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• 2003

This study proposed a modified anisotropic diffusion restoration for image classification. The anisotropic diffusion restoration uses a probabilistic model based on Markov random field, which represents geographical connectedness existing in many remotely sensed images, and restores them through an iterative diffusion processing. In every iteration, the bonding-strength coefficient associated with the spatial connectedness is adaptively estimated as a function of brightness gradient. The gradient function involves a constant called "temperature", which determines the amount of discontinuity and is continuously decreased in the iterations. In this study, the proposed method has been extensively evaluated using simulated images that were generated from various patterns. These patterns represent the types of natural and artificial land-use. The simulated images were restored by the modified anisotropic diffusion technique, and then classified by a multistage hierarchical clustering classification. The classification results were compared to them of the non-restored simulation images. The restoration with an appropriate temperature considerably reduces error in classification, especially for noisy images. This study made experiments on the satellite images remotely sensed on the Korean peninsula. The experimental results show that the proposed approach is also very effective on image classification in remote sensing.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.12 no.6
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• pp.76-85
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• 2009

This study was carried to select the proper vegetation base materials which improve soil quality in abandoned coal mine areas. Also, we aimed at the feasibility of the direct seeding method without soil molding for the ecological restoration in those areas. We set total eight plots within the study site established on an abandoned coal mine area near Taebaek city, Gangwon province in April 2006. The plots were classified as two groups(straw mats mulching and no mulching), and the four treatments (C; control, MI; microbial innoculation, WC; wood chip, OF; organic fertilizer) were applied in each two groups for the soil conditioning. The survival of Pinus densiflora was highest among other species(Betula platyphylla var. japonica, Amorpha fruticosa and Arundinella hirta). For the non straw mat, the survival rate of Pinus densiflora seedlings was highest in the WC treatment($1,756trees/m^2$). For the straw mat, survival rate of Pinus densiflora seedlings was also highest in the WC treatment ($1,622trees/m^2$). In addition, for the non straw mat, the height growth of Pinus densiflora seedling was highest in the OF treatment($12.4{\pm}3.9cm$). For the straw mat, the height growth of Pinus densiflora seedling was also highest in the OF treatment($18.7{\pm}5.3cm$). In general, organic fertilizer treatment with the straw mat was most effective for seedling growth. Also, we suggested that the direct seeding method without soil molding could be sufficiently possible for revegetating abandoned coal mine, Korea.

• Restorative Dentistry and Endodontics
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• v.44 no.3
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• pp.27.1-27.12
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• 2019

This case report describes a technique in which endodontic treatment and permanent indirect restoration were completed in the same clinical appointment with the aid of a computer-aided design/computer-aided manufacturing (CAD/CAM) system. Two patients were diagnosed with irreversible pulpitis of the mandibular first molar. After access preparation, root canals were located, irrigation was performed until bleeding ceased, and the coronal tooth structure was prepared for indirect restoration. Then, utilizing an interim 3-mm build-up of the endodontic access cavity, a hemi-arch digital scan was performed with an intraoral scanner. Subsequent to digital scanning, restoration design was performed simultaneously with the endodontic procedure. The root canals were shaped using the Race system under irrigation with 2.5% sodium hypochlorite followed by root canal filling. The pulp chamber was subsequently filled with a 3-mm-thick composite resin restoration mimicking the interim build-up previously utilized to facilitate block milling in the CAD/CAM system. Clinical try-in of the permanent onlay restoration was followed by acid etching, application of a 5th generation adhesive, and cementation of the indirect restoration. Once the restoration was cemented, rubber dam isolation was removed, followed by occlusal adjustment and polishing. After 2 years of follow-up, the restorations were esthetically and functionally satisfactory, without complications.

• The Journal of Korean Academy of Prosthodontics
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• v.29 no.3
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• pp.87-99
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• 1991

The effect of oven firing on the color stability and surface texture of extrinsic stains used characterization and color modification of metal cermic restoration were studied by comparing different temperatures and techniques. They were autoglaze technique, applied glaze technique, two step low-fusing glaze technique and one step low-fusing glaze technique. Autoglaze technique and applied glaze technique were air-fired to manufacturer's recommended temperature. Two step low-fusing glaze technique is separated staining and overglazing. Thin slurry of stain powder were air-fired to $1500^{\circ}F$, Overglaze powder powder was then mixed with seam medium and air-fired to $170^{\circ}F$. One step low-fusing glaze technique is combined staining and overglazing. Thin slurry of stain and glaze powder were air-fired to $170^{\circ}F$. The obtained results were as fellows. 1. Slightly significant color differences by colorimeter were found between different stain application and fusion techniques(P<0.05). 2. Two step low-fusing glaze method showed the most rough surface, especially ceramco orage stain(P<0.05). 3. Surface roughness increased gradually in order of autoglaze, applied glaze, one step low-fusing glaze but they were not significantly different(P<0.05). 4. When two step low-fusing glaze was applied, both color measurement and surface texture were sinificantly different from other groups(P<0.05).

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.3
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• pp.1367-1372
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• 2011

This paper designed 3D animation in consideration of human characteristics to stimulate their interest and to be more understandable to them. It was also confirmed that, using the 3D animation contents, general people came to recognize the problem of environment pollution and developed desirable attitude and behavior for protecting the environment. Furthermore, this paper suggested the ruins original form restoration technique of the residential environment and the natural environment of Hanyang in the Joseon Dynasty period using the 3D virtual reality digital recovery techniques.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2009.01a
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• pp.684-688
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• 2009

In this paper, it proposes the technique to restore from a binary image in the color image. The color image is composed of three element images of red, green and blue. Therefore, the color image is first divided into a red, green, and blue element, and the Inverse Halftoning[2]$\sim$[4] is processed to each element images. Finally, each element images is collectively displayed. In that case, the Kalman filter was applied to the Inverse Halftoning for the restoration accuracy improvement of the image. As a result, it was possible to restore it in the color image as well as the time of a monochrome image. Moreover, the result that the restoration accuracy had improved even when which combining with the technique by using the Kalman filter for the Inverse Halftoning so far came out.

• Journal of the korean academy of Pediatric Dentistry
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• v.25 no.3
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• pp.627-634
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• 1998

Children who have severely destructive anterior primary dentition, as in nursing-bottle caries, in trauma, in rampant caries and in developmental defects, present the dentist with one of the most perplexing situations in dentistry. Especially, children with managed behavor difficultly is very severly situations. This paper reported a new technique for the utilization of resin post and strip crown to indirect methods on severely destructive primary anterior teeth. We name it "indirect short resin post crown" in this paper. Indirect technique be considered to be a simple, a retentive, intensive, color-stable and esthetic restoration.

• Proceedings of the Korean Society of Computer Information Conference
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• 2011.06a
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• pp.207-211
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• 2011

기업들의 비자금 수사를 받기 전에 압수수색 대상 회계 파일의 삭제, 파손 및 은닉하고 있다. 2010년 H 그룹 비자금 조성 사건에서도 삭제된 파일에서 회계처리, 비자금 문제를 발견하였다. 최근에는 Smart Phone의 활성화와 함께 주요 증거물을 Smart Phone에 저장하고 업무를 진행하고 있다. 본 논문에서는 압수수색된 Smart Phone에서 기업의 회계장부를 찾아내고, 삭제한 회계장부를 복원하는 포렌식 수사기술에 관한 연구이다. 기업에 대한 압수수색 준비와 압수 수색, 획득 증거 분석 등의 절차와 포렌식 도구들을 분석한다. Smart Phone 압수수색 후 포렌식 증거 자료 추출 과정과 포렌식 도구를 이용하여 실험하고 포렌식 증거자료를 추출한다. 본 논문을 통해서 Smart Phone 포렌식 기술발전에 기여 하고자 한다.