• Title/Summary/Keyword: top & down method

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Carbon Nanotube Reinforced Metal Matrix Nanocomposites via Equal Channel Angular Pressing

  • Quang, Pham;Jeong, Young-Gi;Yoon, Seung-Chae;Hong, Sun-Ig;Hong, Soon-Hyung;Kim, Hyoung-Seop
    • Proceedings of the Korean Powder Metallurgy Institute Conference
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    • 2006.09b
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    • pp.980-981
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    • 2006
  • In this study, bottom-up type powder processing and top-down type SPD (severe plastic deformation) approaches were combined in order to achieve full density of Carbon nanotube (CNT)/metal matrix composites with superior mechanical properties by improved particle bonding and least grain growth, which were considered as a bottle neck of the bottom-up method using the conventional powder metallurgy of compaction and sintering. ECAP (equal channel angular pressing), the most promising method in SPD, was used for the CNT/Cu powder consolidation. The powder ECAP processing with 1, 2, 4 and 8 route C passes was conducted at room temperature.

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Design of Self-Timed Standard Library and Interface Circuit

  • Jung, Hwi-Sung;Lee, Moon-Key
    • Proceedings of the IEEK Conference
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    • 2000.07a
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    • pp.379-382
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    • 2000
  • We designed a self-timed interface circuit for efficient communication in IP (Intellectual Property)-based system with high-speed self-timed FIFO and a set of self-timed event logic library with 0.25um CMOS technology. Optimized self-timed standard cell layouts and Verilog models are generated for top-down design methodology. A method for mitigating a design bottleneck when it comes to tolerate clock skew is described. With clock control method and FIFO, we implemented high-speed 32bit-interface chip for self-timed system, which generated maximum system clock is 2.2GHz. The size of the core is about 1.1mm x 1.1mm.

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A Concept on the M&S-based T&E for Ship Acoustics (M&S 기반 함정음향 시험평가 개념)

  • 조창봉
    • Journal of the Korea Institute of Military Science and Technology
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    • v.7 no.1
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    • pp.24-33
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    • 2004
  • Recently, ship acoustics takes more important role in acoustic stealth and classification of underwater targets. In this paper, a theoretical concept is proposed for M&S-based test and evaluation of ship acoustics. The concept is based on two different approaches: on Top-Down method which emphasizes the survivability of the ship and on Bottom-Up method which considers acoustic characteristics of the ship-equipments. In order to improve the effectiveness of M&S-based T&E for ship acoustics, it is recommended in this paper to compromise the two approaches as adequate.

Study on the Selection Method of the Focused Supporting Industries for the Maximization of SMEs' Technological Innovation (중소기업 기술혁신 극대화를 위한 중점지원분야 선정방안 연구)

  • Yoo, Hyoung Sun;Kim, Ji Hui;Jun, Seung-Pyo;Seo, Jinny;Yoo, Jae Young
    • Journal of Korea Technology Innovation Society
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    • v.16 no.1
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    • pp.41-62
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    • 2013
  • In order to facilitate the R&D of SMEs and foster innovative SMEs, the Small and Medium Business Administration is funding the SMEs in the focused supporting industries which are selected by a primary consideration of the political conformity. The correlations among the distribution of engaged SMEs, the distribution of SMEs which applied the fund, and the distribution of SMEs funded in the industries are analysed, in order to realize the effectiveness of the top-down method for selecting the focused supporting industries. As a result, there was a large deviation of both the number of the engaged SMEs and the number of the applied SMEs in the each industry, which means that the selected industries did not accurately reflect the needs for the technology development of SMEs. In addition, the distribution of the applied SMEs was strongly depended on the distribution of the engaged SMEs, which shows the trend that SMEs are trying to make R&D plans in their current industry rather than following the political drive. Moreover, because the distribution of the funded SMEs is strongly correlated with that of the applied SMEs, one could know that the selected industries were neither fostered strategically nor evenly but the fund was distributed simply according to the distribution of the applied SMEs. In this study, in order to complement the limitations of the top-down method, the bottom-up method which primarily consider the needs for the technology development of SMEs was suggested. It is desirable to consider in the order of the needs and the capabilities of SMEs, the technological perspective and marketability of the industry, and the political importance in the bottom-up method, and it is expected that the method could be flexibly used in the planning of the various programs.

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An Adaptive Information Hiding Technique of JPEG2000-based Image using Chaotic System (카오스 시스템을 이용한 JPEG2000-기반 영상의 적응적 정보 은닉 기술)

  • 김수민;서영호;김동욱
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.41 no.4
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    • pp.9-21
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    • 2004
  • In this paper, we proposed the image hiding method which decreases calculation amount by encrypt partial data using discrete wavelet transform and linear scale quantization which were adopted as the main technique for frequency transform in JPEG2000 standard. Also we used the chaotic system which has smaller calculation amount than other encryption algorithms and then dramatically decreased calculation amount. This method operates encryption process between quantization and entropy coding for preserving compression ratio of images and uses the subband selection method and the random changing method using the chaotic system. For ciphering the quantization index we use a novel image encryption algerian of cyclically shifted in the right or left direction and encrypts two quantization assignment method (Top-down/Reflection code), made change of data less. Also, suggested encryption method to JPEG2000 progressive transmission. The experiments have been performed with the proposed methods implemented in software for about 500 images. consequently, we are sure that the proposed are efficient image encryption methods to acquire the high encryption effect with small amount of encryption. It has been shown that there exits a relation of trade-off between the execution time and the effect of the encryption. It means that the proposed methods can be selectively used according to the application areas. Also, because the proposed methods are performed in the application layer, they are expected to be a good solution for the end-to-end security problem, which is appearing as one of the important problems in the networks with both wired and wireless sections.

A Method for Migration of Legacy System into Web Service (레거시 시스템의 웹서비스화를 위한 마이그레이션 기법)

  • Park, Oak-Cha;Choi, Si-Won;Kim, Soo-Dong
    • The KIPS Transactions:PartD
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    • v.16D no.4
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    • pp.583-594
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    • 2009
  • Most of the SOA solutions applicable to businesses and organizations are taking a top-down methodology. It starts with an analysis of an organization's requirements, followed by definition of business models and identification of candidate services and ends with finding or developing required services. Challenges in adopting SOA while abandoning legacy systems involve time and cost required during the process. Many businesses and organizations want to gradually migrate into SOA while making the most of the existing system. In this paper, we propose A Method for Migration of Legacy System into Web Service(M-LSWS); it allows legacy system to be migrated into web service accessible by SOA and be used as data repositories. M-LSWS defines procedures for migration into reusable web services through analysis of business processes and identification of candidate services based on design specification and code of legacy system. M-LSWS aims to migrate of legacy system into web service appropriate for SOA. The proposed method consists of four steps: analysis of legacy system, elicitation of reusable service and its specification, service wrapping and service registration. Each step has its own process and guideline. The eligibility of the proposed method will be tested by applying the method to book management system.

A Study on the Outside Waterproof Method of Ground using Wire-mesh and Non-hardening Viscosity WaterproofBusiness (비경화성 점착 방수제와 보강메쉬를 이용한 지하 외방수 공법에 관한 연구)

  • Moon, You-Seok;Lee, Sin-Chun;Gwon, Gi-Ju;Oh, Sang-Keun
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2009.05b
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    • pp.213-217
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    • 2009
  • Underground structures are built into concrete like a architecture and public works. Concrete has watertightness as such, But buildings are leaking from the cracks. Recently, construction method do a lot of close construction in the downtown area. So architects are using the method for the outer layer of a two-layer wall to save spaces. They have been using Top-down method and waterproof agent method and others to outer layer of a two-layer wall method. But, There are many leakage in underground structure from lack on requirements performance of materials. Therefore, I hope to test the outside Waterproof Method of Ground using Wire-mesh and Non-hardening Viscosity Waterproof. In addition to, I wish to apply as outside waterproof method for the section for the outer layer of a two-layer wall in underground structure.

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The Extraction of Objects between Levels by the boundary Adjustment Algorithm (경계조정 알고리즘에 의한 레벨간의 물체 추출)

  • 최성진;강준길;나극환
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.15 no.2
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    • pp.137-146
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    • 1990
  • A series of images whose sized and resolutions differ by a constant factor are called an image pyramid. Because the images at high levels are small, large object can be detected on high levels of the pyramid at low cost, But in this way, the boundaries of objects are not accurately localized. Therefore the pyramid algorithms extracte the objects by segmentation the constructed image using bottom-up method and description it in an original resolution using inverse bottom-up method. In this paper, we can project an object down to the next lower level of the pyramid and apply to the boundary adjustment algorithm at that level to localize it more precisely. We repeat the process at successively lower levels. In this paper, we present a method of boundary adjustment using an image pyramid to obtain optimal boundary. The performance of the proposed algorithm is compared to those of the conventional method in term of subjective quality of object boundary.

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Optical flow of heart images by image-flow conservation equation and functional expansion (영상유체보존식과 함수전개법에 의한 심장영상의 광류)

  • Kim, Jin-Woo
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.11 no.7
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    • pp.1341-1347
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    • 2007
  • The displacement field (Optical flow) has been calculated by bottom-up approaches based on local processing. In contrast with them, in this paper, a top-down approach based on expanding in turn from the lowest order mode the whole motion in an image pair of sequential images is proposed. The intensity of medical images usually represents a quantity which is conserved during the motion. Hence sequential images are ideally related by a coordinate transformation. The displacement field can be determined from the generalized moments of the two images. The equations which transform arbitrary generalized moments from a source image to a target image are expressed as a function of the displacement field. The appareent displacement field is then computed iteratively by a projection method which utilizes the functional derivatives of the linearized moment equations. This method is demonstrated using a pair of sequential heart images. For comparative evaluation, we applied Horn and Schunck's method, a standard multigrid method, and our proposed algorithm to sequential image.

An Experimental Study on Improvement in Waterproofing Performance of Ground Structures applied to Synthetic Polymeric Sheet of monolithic adhesion Type (일체부착형 합성고분자 시트를 이용한 지하구조물 방수 성능향상에 관한 실험적 연구)

  • Kang, Hyo-Jin;Song, Jei-Young;Kwon, Shi-Won;Oh, Sang-Keun
    • Journal of the Korea Institute of Building Construction
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    • v.5 no.3 s.17
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    • pp.125-129
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    • 2005
  • The waterproofing in slab and wall of underground structure, have a couple of construction methods which are inside waterproofing methods for inner surface, and outside waterproofing methods for out wall and slab surface waterproofing. In resent years, however, it has been adapted the inside waterproofing construction method, as increasing of construction expenses cost and low workability and technology, nevertheless, outside waterproofing has set a most high value construction method. In inside waterproofing construction method, it is difficult to repair and assure durability and safety for concrete which has direct water-press. So, It is necessary for adopt the outside waterproofing method. For that reasons, this study based on the application for outside waterproofing method on the under ground structure, to more increase durability, to introduce mono adhesive sheet waterproofing materials. as considering chemical, physical properties.