• 제목/요약/키워드: Block variance

검색결과 143건 처리시간 0.029초

Comparing accuracy of denture bases fabricated by injection molding, CAD/CAM milling, and rapid prototyping method

  • Lee, Suji;Hong, Seoung-Jin;Paek, Janghyun;Pae, Ahran;Kwon, Kung-Rock;Noh, Kwantae
    • The Journal of Advanced Prosthodontics
    • /
    • 제11권1호
    • /
    • pp.55-64
    • /
    • 2019
  • PURPOSE. The accuracy of denture bases was compared among injection molding, milling, and rapid prototyping (RP) fabricating method. MATERIALS AND METHODS. The maxillary edentulous master cast was fabricated and round shaped four notches were formed. The cast was duplicated to ten casts and scanned. In the injection molding method, designed denture bases were milled from a wax block and fabricated using SR Ivocap injection system. Denture bases were milled from a pre-polymerized block in the milling method. In the RP method, denture bases were printed and post-cured. The intaglio surface of the base was scanned and surface matching software was used to measure inaccuracy. Measurements were performed between four notches and two points in the mid-palatal suture to evaluate inaccuracy. The palatine rugae resolution was evaluated. One-way analysis of variance was used for statistical analysis at ${\alpha}=.05$. RESULTS. No statistically significant differences in distances among four notches (P>.05). The accuracy of the injection molding method was lower than those of the other methods in two points of the mid-palatal suture significantly (P<.05). The degree of palatine rugae resolution was significantly higher in the injection molding method than that in other methods (P<.05). CONCLUSION. The overall accuracy of the denture base is higher in milling and RP method than the injection molding method. The degree of fine reproducibility is higher in the injection molding method than the milling or RP method.

소비자의 의복관여도와 패션잡지광고유형별 광고태도 및 구매의도에 관한 연구 -청 바지광고를 중심으로 (The Fashion Involvement and Attitudes of Consumers toward Advertising and Buying Intensions According to Types of Jeans Advertising in Fashion Magazines)

  • 박지영;정성지;김동건
    • 한국의류학회지
    • /
    • 제34권1호
    • /
    • pp.40-49
    • /
    • 2010
  • This study investigates the differences in: 1) attitudes toward the advertising ofjeans, buying intension, importance of merchandise selection factors, and utilization of information sources among groups according to the level of fashion involvement 2) attitudes toward advertising and buying intension among types of advertising 3) importance among merchandise selection factors 4) utilization among types of information source. Questionnaires were distributed to 300 men and women between 10 and 30 years of age. A sample of 286 men and women responded to the questionnaire. Using SPSS/PC version 12.0, factor analysis, reliability analysis, analysis of variance, and randomized block design are used for the data analysis. The results showed significant differences in: 1) attitudes toward the advertising of jeans, buying intension, importance of merchandise selection factors, and utilization of information source among groups according to levels of fashion involvement 2) attitudes toward advertising and buying intension among types of advertising 3) importance among merchandise selection factors 4) utilization among types of information sources.

연속 블록간의 화소차이 행렬을 이용한 워터마크 알고리즘 (Watermark Algorithm Using Difference Matrix between Successive Blocks)

  • 박기홍;김윤호
    • 한국항행학회논문지
    • /
    • 제12권3호
    • /
    • pp.273-279
    • /
    • 2008
  • 본 논문에서는 웨이블릿 기반 화소차이 행렬을 이용한 워터마킹 알고리즘을 제안하였다. 전처리과정으로 1-레벨 웨이블릿 변환을 수행한 후, 저주파 대역을 제외한 고주파 대역부분의 계수 블럭을 정규화하여 웨이블릿역변환을 거쳐 참조 영상을 만든다. 원 영상과 참조 영상의 인접블럭에 대한 분산을 계산하고 고주파 성분이 원 영상에 미치는 지역적 특성을 고려하여 워터마크를 삽입한다. 실험결과, 제안한 방법이 비가시성이 우수하고 외부공격(잡음첨가, 필터링, JPEG)의 영상처리에 강인함을 확인하였다.

  • PDF

순환 DFT 기반의 동기 위상 측정에 있어서 계수 근사에 따른 성능 열화 분석 (Performance degradation caused by coefficient approximation in Sliding-DFT based phasor measurement)

  • 김종윤;장태규
    • 대한전자공학회논문지SP
    • /
    • 제39권4호
    • /
    • pp.470-476
    • /
    • 2002
  • 본 논문에서는 순환 DFT 기반의 위상 측정 알고리즘을 구현함에 있어서 계수 근사 및 주파수 변이에 따른 성능 열화를 해석하였다. 오차의 영향을 해석하기 위해서 근사 순환 DFT식을 이용하여 오차 방정식(error dynamics)을 정의하고 이의 통계적 특성을 이용하여 오차의 특성을 분석한다. 오차 전력은 오차파급의 주요 영향 요소인 근사 bit수, DFT 구간 길이와 잡음에 관한 closed-form으로 유도되어 진다. 해석적으로 유도한 식과 시뮬레이션 실험을 통해 얻을 결과를 비교하여 타당성을 확인하였다.

Implementation of Timing Synchronization in Vehicle Communication System

  • Lee, Sang-Yub;Lee, Chul-Dong;Kwak, Jae-Min
    • Journal of information and communication convergence engineering
    • /
    • 제8권3호
    • /
    • pp.289-294
    • /
    • 2010
  • In the vehicle communication system, transferred information is needed to be detected as possible as fast in order to inform car status located in front and rear side. Through the moving vehicle information, we can avoid the crash caused by sudden break of front one or acquire to real time traffic data to check the detour road. To be connecting the wireless communication between the vehicles, fast timing synchronization can be a key factor. Finding out the sync point fast is able to have more marginal time to compensate the distorted signals caused by channel variance. Thus, we introduce the combination method which helps find out the start of frame quickly. It is executed by auto-correlation and cross-correlation simultaneously using only short preambles. With taking the absolute value at the implemented synch block output, the proposed method shows much better system performance to us.

이단계 지분계획법의 오차제곱합 유도와 그 활용 (Derivation of error sum of squares of two stage nested designs and its application)

  • 김대학
    • Journal of the Korean Data and Information Science Society
    • /
    • 제24권6호
    • /
    • pp.1439-1448
    • /
    • 2013
  • 확률화 블록계획법이나 교차된 이원분류표에 대한 분산분석과 오차제곱합의 성질은 널리 알려져있다. 본 논문에서는 인자에 따른 수준에 또 다른 인자들이 내포되어 있는 지분계획 특히 이단계 지분계획에 대하여 구조적 특징을 설명하고 오차제곱합의 성질에 대하여 살펴보았다. 또한 이단계 지분계획의 활용으로 크로스오버 계획을 소개하고 생물학이나 약학 등의 분야에서 많이 사용되는 동등성 검정의 신뢰구간 구축에 대하여 설명하였고 실제자료와 SPSS 통계 페키지를 이용하여 분석함으로서 응용성을 부각시켰다.

STUDY OF REPRODUCTIVE POTENTIAL OF BALUCHI SHEEP ON RANGES IN BALUCHISTAN

  • Rafiq, Mohammed;Sultani, M.I.;Munir, M.;Arshad, A.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • 제3권3호
    • /
    • pp.177-182
    • /
    • 1990
  • A reproductive potential trial using randomized complete block design with $3{\times}3{\times}2$ factorial, was conducted on 84 Baluchi yearling ewes. Ewes grazed on rangeland dominated by Artemisia maritime and Holoxylon grifthii with or without flushing and supplementation of barley grain (BG) and cotton-seed-cake (CSC) during premating, late pregnancy and lactation of 90 days. Analysis of variance revealed that conception rate which ranged 64.28 to 85.71, was significantly greater (p<.05) in ewes flushed with CSC followed by ewes under BG or control feeding regimes. During the gestation period, liveweight of ewes changed from 31.24 to 21.2 kg. A loss of 32% of initial body weight was observed at lambing. Losses in live weight of ewes, regardless the supplementation, were uniform and non-significantly different. Live weight of ewes at lambing and weaning were also similar. Birth weight of lambs was significantly different at p<.05. Lambs born to larger ewes seemed to be heavier than lighter ones. Lambs suckling to ewes with losses in body weight during lactation gained more weight which was significantly different at p<.05. In the paper, factors affecting the conception rate, changes in liveweight of ewes during gestation and lactation and subsequently growth of lambs are discussed.

Various autogenous fresh demineralized tooth forms for alveolar socket preservation in anterior tooth extraction sites: a series of 4 cases

  • Kim, Eun-Suk;Lee, In-Kyung;Kang, Ji-Yeon;Lee, Eun-Young
    • Maxillofacial Plastic and Reconstructive Surgery
    • /
    • 제37권
    • /
    • pp.27.1-27.7
    • /
    • 2015
  • The aim of this study was to evaluate the clinical relevance of autogenous fresh demineralized tooth (Auto-FDT) prepared at chairside immediately after extraction for socket preservation. Teeth were processed to graft materials in block, chip, or powder types immediately after extraction. Extraction sockets were filled with these materials and dental implants were installed immediately or after a delay. A panoramic radiograph and a conebeam CT were taken. In two cases, tissue samples were taken for histologic examination. Vertical and horizontal maintenance of alveolar sockets showed some variance depending on the Auto-FDT and barrier membrane types used. Radiographs showed good bony healing. Histologic sections showed that it guided good new bone formation and resorption pattern of the Auto-FDT. This case series shows that Auto-FDT prepared at chairside could be a good material for the preservation of extraction sockets. This study will suggest the possibility of recycling autogenous tooth after immediate extraction.

A Novel Multifocus Image Fusion Algorithm Based on Nonsubsampled Contourlet Transform

  • Liu, Cuiyin;Cheng, Peng;Chen, Shu-Qing;Wang, Cuiwei;Xiang, Fenghong
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • 제7권3호
    • /
    • pp.539-557
    • /
    • 2013
  • A novel multifocus image fusion algorithm based on NSCT is proposed in this paper. In order to not only attain the image focusing properties and more visual information in the fused image, but also sensitive to the human visual perception, a local multidirection variance (LEOV) fusion rule is proposed for lowpass subband coefficient. In order to introduce more visual saliency, a modified local contrast is defined. In addition, according to the feature of distribution of highpass subband coefficients, a direction vector is proposed to constrain the modified local contrast and construct the new fusion rule for highpass subband coefficients selection The NSCT is a flexible multiscale, multidirection, and shift-invariant tool for image decomposition, which can be implemented via the atrous algorithm. The proposed fusion algorithm based on NSCT not only can prevent artifacts and erroneous from introducing into the fused image, but also can eliminate 'block effect' and 'frequency aliasing' phenomenon. Experimental results show that the proposed method achieved better fusion results than wavelet-based and CT-based fusion method in contrast and clarity.

영상압축을 위한 코넨네트워크 (KOHONEN NETWORK FOR ADAPTIVE IMAGE COMPRESSION)

  • 손형경;이영식;배철수
    • 한국정보통신학회:학술대회논문집
    • /
    • 한국해양정보통신학회 2001년도 추계종합학술대회
    • /
    • pp.571-574
    • /
    • 2001
  • 본 논문에서는 코호넨 네트워크를 이용한 효과적인 적응 코딩 방법을 제안한다. 신경망을 응용한 압축법 분석을 통해 설명되는 코딩방법은 압축률을 높이기 위해서 우선 영상을 8$\times$8 부영상으로 나누고, 나눠진 모든 부영상은 DCT로 변형한다. 이들 DCT 부블럭들은 코호넨 네트워크로 N(4) 등급으로 나누어지게 되고, 비트들은 DCT 부블럭의 변수에 따라 분류된다. 그래서 N(4)비트 할당 행렬을 얻었다. 실험 결과는 시뮬레이션으로 나타내었고, 제안한 방법이 신경네트워크에서의 AC 에너지에 의해 부영상을 분류하는 것보다 우수하다는 결론을 얻을 수 있었다.

  • PDF