• Title/Summary/Keyword: Block

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A Strategy of a Gap Block Design in the CFRP Double Roller to Minimize Defects during the Product Conveyance (제품 이송 시 결함 최소화를 위한 CFRP 이중 롤러의 Gap block 설계 전략)

  • Seung-Ji Yang;Young-june Park;Sung-Eun Kim;Jun-Geol Ahn;Hyun-Ik Yang
    • Composites Research
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    • v.37 no.1
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    • pp.7-14
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    • 2024
  • Due to the structural characteristic of a double roller, the double roller can have various deformation behaviors depending on a gap block design, even if dimensions and loading conditions for the double roller are the same. Based on this feature, we propose a strategy for designing the gap block of the carbon-fiber reinforced plastic (CFRP) double roller to minimize defects (e.g., sagging and wrinkling), which can be raised during the product conveying process, with the pursue of the lightweight design. In the suggested strategy, analysis cases are first selected by considering main design parameters and engineering tolerances of the gap block, and then deformation behaviors of these selected cases are extracted using the finite element method (FEM). Here, to obtain the optimal gap block parameters that satisfy the purpose of this study, deformation deviations in the contact area are calculated and compared using the extracted deformation behaviors. Note that the contact area in this work is located between the product and the roller. As a result, through the design method of the gap block proposed in this work, it is possible to construct the CFRP double roller that can significantly decrease the defects without changing the overall sizes of the roller. A detailed method is suggested herein, and the results are evaluated in a numerical way.

Synthesizing Intermediate Images Using Stereoscopic Images

  • Kwak, Ji-Hyun;Komar, V.S.V.;Kim, Kyung-Tae
    • Journal of the Optical Society of Korea
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    • v.6 no.4
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    • pp.143-149
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    • 2002
  • In this paper, we present an algorithm for synthesizing intermediate views from a stereoscopic pair of images. Syntheses of intermediate images allows one to realize a more comfortable the 3D display system. The proposed method is based on block matching, which is not ordinarily used. The contour information is used for a block decision. In order to find an equivalent (or corresponding) block, there are two steps: "matching of contour-to-original image" and "matching of contour-to-contour image" methods. "Matching of contour-to-contour image" uses both left and right contour images. This block matching method allows us to find the corresponding block in spite of different block sizes. Experimental results illustrate the performance of the proposed technique and we obtained a high quality image of more than 31 dB PSNR.image of more than 31 dB PSNR.

A Memory-Efficient Block-wise MAP Decoder Architecture

  • Kim, Sik;Hwang, Sun-Young;Kang, Moon-Jun
    • ETRI Journal
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    • v.26 no.6
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    • pp.615-621
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    • 2004
  • Next generation mobile communication system, such as IMT-2000, adopts Turbo codes due to their powerful error correction capability. This paper presents a block-wise maximum a posteriori (MAP) Turbo decoding structure with a low memory requirement. During this research, it has been observed that the training size and block size determine the amount of required memory and bit-error rate (BER) performance of the block-wise MAP decoder, and that comparable BER performance can be obtained with much shorter blocks when the training size is sufficient. Based on this observation, a new decoding structure is proposed and presented in this paper. The proposed block-wise decoder employs a decoding scheme for reducing the memory requirement by setting the training size to be N times the block size. The memory requirement for storing the branch and state metrics can be reduced 30% to 45%, and synthesis results show that the overall memory area can be reduced by 5.27% to 7.29%, when compared to previous MAP decoders. The decoder throughput can be maintained in the proposed scheme without degrading the BER performance.

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Experimental Study on Performance Characteristics with Various Spacings between Automobile Cooling Fan and Engine Block (차량용 냉각 팬과 엔진 블럭의 간격 변화에 따른 성능 특성 연구)

  • Yu, Byoung-Min;Ryu, Ki-Wahn;Jang, Jea-Kyung;Ih, Kang-Duck;Hong, Sung-Kyu
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2009.10a
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    • pp.143-149
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    • 2009
  • Recently, according to the tendency to the more comfortable automobile, the improvement of performance of the cooling fan is required. The performance of cooling fan is affected by many peripheral parts, such as radiator, condenser, engine block and etc. Therefore, it is important to consider the effect of peripheral components on the fan performance in design and analysis stages. In this paper, the performance of automobile cooling fan is investigated experimentally by using the large capacity fan tester based on the ASHRAE and the AMCA standards. In particular, the various spacing between cooling fan and engine block are considered to obtain the effect of engine block. An empirical relation between the fan flow rate and the spacing was proposed.

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Content Based Image Retrieval Based on A Novel Image Block Technique Combining Color and Edge Features

  • Kwon, Goo-Rak;Haoming, Zou;Park, Sei-Seung
    • Journal of information and communication convergence engineering
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    • v.8 no.2
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    • pp.185-190
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    • 2010
  • In this paper we propose the CBIR algorithm which is based on a novel image block method that combined both color and edge feature. The main drawback of global histogram representation is dependent of the color without spatial or shape information, a new image block method that divided the image to 8 related blocks which contained more information of the image is utilized to extract image feature. Based on these 8 blocks, histogram equalization and edge detection techniques are also used for image retrieval. The experimental results show that the proposed image block method has better ability of characterizing the image contents than traditional block method and can perform the retrieval system efficiently.

Smart Device Based Localization for Ship Block Logistics

  • Song, Kwon-Soo;Lee, Sangdon;Cho, Doo-Yeoun
    • Journal of Korea Multimedia Society
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    • v.15 no.12
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    • pp.1506-1516
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    • 2012
  • In a ship block logistics application, acquisition of locations is required in order to identify location of the ship blocks. A Smart device equipped with a GPS sensor can be used as a mobile client for a ship block logistics application. However the precision of GPS components on a commercial smart device is not high enough. Therefore, using the GPS for localization may produce significant positioning errors in a ship block logistics system. This paper proposes a method to reduce errors in measuring locations using a smart device. Based on the knowledge of how the location information is used in a ship block logistics application, and the predictability of the client's moving line based on geographical layout of a shipyard area, our proposed technique enables a better prediction of the ship blocks location. Performance evaluation shows that the proposed technique can significantly reduce the positional error.

Updates on the Inferior Alveolar Nerve Block Anesthesia (하치조신경전달마취의 최신지견)

  • Paeng, Jun-Young
    • Journal of The Korean Dental Society of Anesthesiology
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    • v.14 no.1
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    • pp.3-10
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    • 2014
  • The inferior alveolar nerve (IAN) block is the most frequently used mandibular injection technique for achieving local anesthesia for restorative and surgical procedures. However, The IAN block does not always result in successful anesthesia, especially pulpal anesthesia. Lidocaine is used as a "standard" local anesthetic for the inferior alveolar nerve. Articaine recently joined Korean market as a form of dental cartridge. It has an advantage of superior diffusion through bony tissue. A variety of trial was performed to improve the success rate of inferior alveolar nerve block. In this review, the recent update related with inferior alveolar nerve block anesthesia will be discussed on the anatomical consideration, anesthetic agent, technique, and complications.

A Fundamental Study on the Shape Development of Planting Concrete Block Using Recycled Aggregates (재생골재를 이용한 식재용 콘크리트 블록의 형태개발에 관한 기초적 연구)

  • 김경민;백명숙;이상태;최청각;김기철;한천구
    • Proceedings of the Korea Concrete Institute Conference
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    • 2002.10a
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    • pp.261-264
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    • 2002
  • This study is intended to develop the new concrete block for planting through investigating weight and basic physical properties, varying the shapes of concrete block for planting. According to the results, unit weight, void ratio and absorption water ratio of concrete block show 1625kg/$m^3M$ 30%, and 7.7% respectively, and pH is small, compared with non neutralization and pH is below 8.5 after 7 days elapses. The compressive strength of concrete block for planting shows 38kgf/$cm^2$ at the age of 7 days, and 50kgf/$cm^2$ at the age of 28 days respectively. As the number of the hole is many and the area of hollow is large, weight of developed concrete block for planting grow light. Weight of optimum scheme with 2 hollow is reduced by 25%.

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An Intermediate Image Generation Method using Multiresolution-based Hierarchical Disparity Map (다해상도 기반 계층적 변이맵을 이용한 중간영상 생성 방법)

  • 허경무;유재민
    • Journal of Institute of Control, Robotics and Systems
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    • v.9 no.11
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    • pp.899-905
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    • 2003
  • An intermediate images generation method using multi-resolution based hierarchical block matching disparity map is proposed. This method is composed of a disparity estimation, an occlusion detection and intermediate image synthesis. For the disparity estimation, which is one of the important processes in intermediate image synthesis, we use the multi-resolution based hierarchical block matching algorithm to overcome the imperfect ness of block matching algorithm. The proposed method makes disparity maps more accurate and dense by multi-resolution based hierarchical block matching, and the estimated disparity maps are used to generate intermediate images of stereo images. Generated intermediate images show 0.1∼1.4 ㏈ higher PSNR than the images obtained by block matching algorithm.

Counter Chain: A New Block Cipher Mode of Operation

  • El-Semary, Aly Mohamed;Azim, Mohamed Mostafa A.
    • Journal of Information Processing Systems
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    • v.11 no.2
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    • pp.266-279
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    • 2015
  • In this paper, we propose a novel block cipher mode of operation, which is known as the counter chain (CC) mode. The proposed CC mode integrates the cipher block chaining (CBC) block cipher mode of operation with the counter (CTR) mode in a consistent fashion. In the CC mode, the confidentiality and authenticity of data are assured by the CBC mode, while speed is achieved through the CTR mode. The proposed mode of operation overcomes the parallelization deficiency of the CBC mode and the chaining dependency of the counter mode. Experimental results indicate that the proposed CC mode achieves the encryption speed of the CTR mode, which is exceptionally faster than the encryption speed of the CBC mode. Moreover, our proposed CC mode provides better security over the CBC mode. In summary, the proposed CC block cipher mode of operation takes the advantages of both the Counter mode and the CBC mode, while avoiding their shortcomings.