• Title/Summary/Keyword: Block variance

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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
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    • v.11 no.1
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    • pp.55-64
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    • 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.

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

  • Park, Ji-Young;Chung, Sung-Jee;Kim, Dong-Geon
    • Journal of the Korean Society of Clothing and Textiles
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    • v.34 no.1
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    • pp.40-49
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    • 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.

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

  • Park, Ki-Hong;Kim, Yoon-Ho
    • Journal of Advanced Navigation Technology
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    • v.12 no.3
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    • pp.273-279
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    • 2008
  • In this paper, we proposed a watermarking algorithm by using difference matrix between successive blocks in the transform domain. In the preprocessing, original image is decomposed with 1-level sub-bands by DWT. Then, all sub-bands which are excepted the low-frequency bands are set to normalize and make a reference image after transforming inverse DWT. The statistic variance of successive blocks between the original image and the reference image are calculated and finally, watermark is embedded considering the local characteristic with respect to the high-frequence components. Experimental results showed that the proposed approach is robust and better invisible in such attacks as filtering, JPEG and noise addition.

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

  • Kim, Chong-Yun;Chang, Tae-Gyu
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.39 no.4
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    • pp.470-476
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    • 2002
  • This paper presents an analysis of the performance degradation of coefficient approximation and frequency deviation in phase measurement algorithm based on Sliding-DFT. The analytic derivation is based on the statistics of the error dynamic equation that describes the error propagation of the recursion. The analysis result is intended to obtain a closed-form equation of error variance in terms of the number of bits used in coefficient approximation, the length of the DFT data block, and noise. It is verified with data obtained from the computer simulations.

Implementation of Timing Synchronization in Vehicle Communication System

  • Lee, Sang-Yub;Lee, Chul-Dong;Kwak, Jae-Min
    • Journal of information and communication convergence engineering
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    • v.8 no.3
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    • pp.289-294
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    • 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.

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

  • Kim, Daehak
    • Journal of the Korean Data and Information Science Society
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    • v.24 no.6
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    • pp.1439-1448
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    • 2013
  • The analysis of variance for randomized block design or two way classification data is well known. In this paper, particularly, we considered two stage nested design in which the levels of one factor is not identical for different levels of another factor. We investigate the structural properties of two stage nested design and the properties of error sum of squares for random effect model. For the application of two way nested design, we consider two-period crossover design which is used commonly for the equivalence test to bio-similar product. The confidence interval estimation of the difference of two population means in the crossover design is discussed based on statistical package SPSS.

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
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    • v.3 no.3
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    • pp.177-182
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    • 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
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    • v.37
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    • pp.27.1-27.7
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    • 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)
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    • v.7 no.3
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    • pp.539-557
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    • 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.

KOHONEN NETWORK FOR ADAPTIVE IMAGE COMPRESSION (영상압축을 위한 코넨네트워크)

  • 손형경;이영식;배철수
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2001.10a
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    • pp.571-574
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    • 2001
  • In our paper, We propose an efficient adaptive coding method using kohonen neural network. An efficient adaptive encoding method using Kohonen net work is discribed through the analysis of those compression methods with the application of the neural network. In order to increase the compression ratio, a image is first divided into 8*8 subimages, then all subimages are transformed by DCT. These DCT sub-blocks are divided into N(4) classes by Kohonen network. Hits are distributed according to the variance of the DCT sub-block. Thus we get N(4)bit allocation matrices. Excellent performance is shown by the computer simulation. so we found that our proposed method is better then classifing subimages by AC energy.

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