• 제목/요약/키워드: restoration techniques

검색결과 474건 처리시간 0.022초

두 성분을 이용한 전력품질 신호의 압축 및 복구 (Power Quality Signal Compression and Restoration based on Two Component)

  • 정영식;김철
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2006년도 제37회 하계학술대회 논문집 A
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    • pp.125-126
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    • 2006
  • Data storage and data communication currently pose a major problems for all parties involved with power quality and power system monitoring. The Problem aries from the tremendous amount of data involved. There is a common desire in the power industry to find new techniques for high-accuracy data compression and data storage. This paper introduces a data compression technique that is very suitable for application to power quality waveforms. The proposed technique is applied in splitting the monitored signal into two components. Those are stationary and nonstationary components. Each component is compressed and encoded.

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INDIRECT BONDING TECHNIQUE에 대한 고찰 (CLINICAL CONSIDERATION OF INDIRECT BONDING TECHNIQUE)

  • 이경환;김상철
    • 대한치과교정학회지
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    • 제19권2호
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    • pp.155-163
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    • 1989
  • Indirect bonding is done by placing the brackets on a model in the laboratory and using a template or tray to transfer the laboratory positioning to the teeth. The advantages of this technique are 1. decreased chair time 2. less patient discomfort 3. accuracy of a attachment placement 4. good adaptation of attachment to tooth contour 5. occlusal relationship of brackets and opposing teeth can be checked The disadvantages of the technique are 1. complex laboratory procedure 2. sometimes difficult on very short clinical crowns 3. teeth with crowns, large buccal restoration will not bond 4. may not be fitted close, if poor adaptation 5. likely to be disturbed setting Several indirect bonding techniques have proved reliable in clinical practice. However, they differ in the way the brackets are attached temporarily to the model, the type of transfer tray or other mechanism used, the adhesive or sealant employed, whether segmented or full bonding used, and the way the transfer is removed so as not to exert excessive force on a still maturing bond.

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배전 계통에서의 고장점 진단 전문가 시스템 개발 (An Exper System for Dignosis of Fault Location on Electric Power Distribution System)

  • 진보건;이덕수;이승재;강상희;최면송;안복신;윤남선
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 춘계학술대회 논문집 전력기술부문
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    • pp.319-321
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    • 2001
  • When the fault occurred at distribution system, the restoration was late. There are 2 reasons The one is the error of fault location the other is multiple possible candidates of fault location. This paper presents two of new techniques for diagnosing fault regions. The proposed diagnosis scheme is capable of accurately identifying the location of fault upon its occurrence. based on the integration of information available from protective devices and measured load current change at the substation. In this paper expert system for real fault region is presented using these facts. Testing of the developed system using EMTP Simulation Model has demonstrated.

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음질 개선을 위한 돌발잡음 제거와 음성복원 (Abrupt Noise Cancellation and Speech Restoration for Speech Enhancement)

  • 손백권;한민수
    • 대한음성학회:학술대회논문집
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    • 대한음성학회 2003년도 10월 학술대회지
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    • pp.101-104
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    • 2003
  • In this paper, speech quality is improved by removing abrupt noise intervals and then substituting the gaps with estimates of the previous speech waveform. An abrupt noise detection signal has been proposed as a prediction error signal by utilizing LP coefficients of the previous frame. Abrupt noise intervals are estimated by using spectral energy. After removing estimated noise intervals, we applied several waveform substitution techniques such as zero substitution, previous frame repetition, pattern matching, and pitch waveform replication. To prove the validity of our algorithm, the LPC spectral distortion test and the recognition test are executed and, the results show that the speech quality is fairly well improved.

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정지영상의 Blocking Artifact를 제거하기 위한 후처리 알고리즘 (Postprocessing Algorithm for Reduction of Blocking Artifact in Still Images)

  • 장동식;유헌우;손용준;채경호
    • 제어로봇시스템학회논문지
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    • 제8권6호
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    • pp.462-467
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    • 2002
  • A new approach for reducing the blocking artifact is proposed in this paper. This method can be applied to conventional transform coding, without introducing additional information or significant blurring. Main drawbacks of the Discrete Cosine Transform(DCT) are visible block boundaries due to coarse quantization of the coefficients. Therefore, restoration techniques result in unnecessary blurring of the image. The proposed deblocking algorithm is based on the heuristic approach for edge detection. All edges of the standard still images are categorized, and the best edges are selected. Several images are used fer experiments, and several other previous algorithms are compared with the proposed approach. The results show that the proposed algorithm works better than those of other previous researches. This algorithm can be used for JPEG, MPEG, and H.261 standard images.

총의치의 자연스러운 치은형성법에 관한 연구 (A Study on Improving Techniques of Festooning for Denture Base)

  • 신무학;김연수;최운재;정희선
    • 대한치과기공학회지
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    • 제25권1호
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    • pp.103-109
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    • 2003
  • The purpose of this study is to ensure natural restoration of gingiva's form by making effective use of materials in a bid to improve the technique of festooning for denture base. 1. The improved technique is expected to prevent the degradation and deformation of cavity structure and restore it. 2. The improved technique is expected to prevent the change of facial appearance from esthetic viewpoint and restore it. 3. The improved technique is expected to impress again the deformed part on wax denture for additional festooning.

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A Study on the Reliability of the Distribution Automation System for the Lightning Effect

  • Shin, Jung-Jin;Lee, Hee-Tae;Kim, Jae-Chul
    • 조명전기설비학회논문지
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    • 제23권11호
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    • pp.76-83
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    • 2009
  • In today's competitive power market, electric power utilities have strived to provide energy at an acceptable level of quality due to increased expectations from customers. For this reason, electric power utilities have invested in electric equipment and new techniques. That is the Distribution Automation System (DAS). A merit of DAS is the ability to reduce outage time because of fast service restoration. However, DAS is usually installed in outdoor environments. Therefore, their efficiency is affected by the external conditions. Lightning creates varying degrees of physical stress on DAS. This paper focuses on the reliability of DAS for lightning. Four application studies were performed to compare the reliability indices.

프렌치 후드 제작에 관한 고찰 I (A Study on the Restoration of Frenchhood)

  • 김경희;문윤경
    • 복식문화연구
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    • 제11권2호
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    • pp.243-252
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    • 2003
  • The study was designed to review the changes in designs and the manufacturing methods of french hood, one of the headdresses which play an important role in showing the appearance of costume, to understand design expression techniques through manufacturing of the head dress of the western costumes, and to provide materials to exert creativity for new designs. Based on literature review and portrait study, 1 manufactured a frenchhood. I set the study cope as from the late 15 century when frenchhood was used for the first time, to the mid 16 century. For the frenchhood selected, 1 examined the hair style, the characteristics of the french hood, and the pattern first, and proceeded to manufacturing. 1 used velvet and silk for the textile as explained in the literature. And, 1 purchased such similar ornaments as shown in the pictures, making the color so similar to the original to the most. Dimensions in manufacturing were those In the literature, since the study is focusing on the reproduction of the features of the portraits. Dimensions of detailed decoration were measured using the ratio of the headdress in the portraits.

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Digital Image Enhancement Algorithm

  • Yoo, Suk Won
    • International Journal of Advanced Culture Technology
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    • 제4권3호
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    • pp.48-55
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    • 2016
  • Conventional techniques for solving the noise problem have problems to generate different results, depending on the image size and weight values of the used masks, and they require many operations by using a complex formula. In this paper, we propose an image enhancement algorithm to solve the noise problem in a simple, yet easy-to-use way. For this purpose, we determined the difference between the noise of the two adjacent pixels for the horizontal and vertical, and for the two diagonal directions that each of the noise problem occurred, and then we got the average value of these pixel values. Then, we solve the noise problem by using the optimal average value in accordance with occurrence of the noise in the horizontal and vertical, and two adjacent pixels in a diagonal direction. As a result, we got the result that the noise solution in a simple, yet easy-to-use method to obtain a resultant image.

Tooth-colored Adhesive Restoration for Posterior Teeth

  • Krejci, I.
    • 대한치과보존학회:학술대회논문집
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    • 대한치과보존학회 2001년도 추계학술대회(제116회) 및 13회 Workshop 제3회 한ㆍ일 치과보존학회 공동학술대회 초록집
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    • pp.579-579
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    • 2001
  • One of the most important factors for the clinical success of adhesive posterior restorations is marginal adaptation. This property is very closely related to mechanical properties and to the shrinkage behavior of composite materials. Most of modem composite materials are light-cured. This is why the first part of this lecture will be confined to our recent research on light curing, such as plasma polymerization, LED polymerization and the power of modem halogen lamps. In the second part of the lecture the shrinkage properties such as dimensional shrinkage and shrinkage forces of different light curing materials and during different curing procedures will be discussed. Finally, in the third part of the lecture, marginal adaptation before and after loading in different cavity classes and by using different restorative techniques and curing procedures will be presented. Data will also be given on wear resistance, abrasiveness against opposing cusps and postcuring of composite materials.(omitted)

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