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Design of the Content Packager for DRM-based Distribution System (DRM 기반 유통시스템을 위한 컨텐츠 패키저 설계)

  • Park, Ji-Hyun;Yoon, Ki-Song;Park, Chang-Soon
    • Proceedings of the Korea Information Processing Society Conference
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    • 2002.11c
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    • pp.2325-2328
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    • 2002
  • DRM 을 통한 저작권 보호는 대부분 컨텐츠를 암호화하여 보호하고, 요금을 지불한 사용자에게 컨텐츠를 부호화할 수 있는 암호화키를 포함한 라이센스를 발급하여 컨텐츠를 사용할 수 있도록 하는 방법을 사용한다. 암호화된 컨텐츠는 내부 정보를 보호할 수 있도록 설계된 secure container 라는 구조체에 컨텐츠에 대한 메타데이터 및 컨텐츠 사용에 관한 비즈니스 룰과 함께 패키징되어 구매자에게 배포된다. 현재 개발된 DRM 시스템들은 컨텐츠 유통업자와 구매자 사이의 단순한 유통 모델을 지원하도록 설계되어 있으므로 패키징 작업 또한 유통업자에서만 수행된다. DRM 을 통한 컨텐츠 유통이 활성화되면 컨텐츠 제작자에서부터 제공자, 유통업자, 구매자에 이르는 모든 컨텐츠 유통 채널에서 컨텐츠가 보호되어야 하며, 이런 경우 각 유통주체에서 컨텐츠의 패키징이 발생할 수 있다. 이처럼 다양한 유통 모델에서의 컨텐츠 보호를 위해서는 각 유통 모델을 지원할 수 있도록 유연한 구조로 secure container를 설계하고 이를 지원하는 도구로써 컨텐츠 패키저를 설계하여야 한다. 본 논문에서는 유연성 있는 컨텐츠 패키저의 구조를 기술하고 컨텐츠 창조자, 유통업자, 구매자가 참여하는 유통모델에서 이를 적용하여 보고자 한다.

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Prediction of fracture in Hub-hole Expansion Process Using Ductile fracture Criteria (연성파괴기준을 이용한 허브홀 확장과정에서의 파단 예측)

  • Ko, Y. K.;Lee, J. S.;Huh, H.;Kim, H. K.;Park, S. H.
    • Transactions of Materials Processing
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    • v.14 no.7 s.79
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    • pp.601-606
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    • 2005
  • A hole expansion process is an important process in producing a hub-hole in a wheel disc of a vehicle. In this process, the main parameter is the formability of a material that is expressed as the hole expansion ratio. In the process, a crack is occurred in the upper edge of a hole as the hole is expanded. Since prediction of the forming limit by hole expansion experiment needs tremendous time and effort, an appropriate fracture criterion has to be developed for finite element analysis to define forming limit of the material. In this paper, the hole expansion process of a hub-hole is studied by finite element analysis with ABAQUS/standard considering several ductile fracture criteria. The fracture mode and hole expansion ratio are compared with respect to the various fracture criteria. These criteria do not predict its fracture mode or hole expansion ratio adequately and show deviation from experimental results of hole expansion. A modified ductile fracture criterion is newly proposed to consider the deformation characteristics of a material accurately in a hole expansion process. A fracture propagation analysis at the hub-hole edge is also performed for high accuracy of prediction using the new fracture criterion proposed.

Design of Electric Transformer Supply Chain System using Metal Surface Mountable RFID Tag (금속 표면 실장용 RFID 태그를 이용한 변압기 자재 관리 시스템 설계)

  • Park, Chong-Ryol;Yun, Kee-Bang;Eom, Ki-Hwan
    • 전자공학회논문지 IE
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    • v.48 no.4
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    • pp.7-12
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    • 2011
  • This paper described a metal mount RFID tag that works reliably on metallic surface. The proposed method is to use commercial RFID tags, Styrofoam103.7 material is attached on back side of RFID tag. Styrofoam103.7 material which has 2.5 mm thickness and 1.03 relative permittivity, was attached on back side of RFID tag. In order to verify the performance of proposed method, we evaluated the experiment on the supply chain system of electric transformers using RFID. The experimental results on supply chain of electric transformers show that the proposed tags can communicate with readers from a distance of 2 m. The results of recognition rates are comparable to commercial metallic mountable tags.

Evaluation of Role Flangeability of Steel Sheet with respect to the Role Processing Condition (가공조건에 따른 강판의 구멍확장성 평가)

  • Lee, J.S.;Kim, Y.K.;Huh, H.;Kim, H.K.;Park, S.H.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2006.05a
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    • pp.359-362
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    • 2006
  • In this paper, hole expanding tests are carried out in order to identify the effect of the hole process condition on the hole expanding ratio. Specimens with two different hole conditions are prepared: one is produced with punching process; and the other is reamed after punching to get smoother hole surface. The experimental results show that the facture mechanism and the hole expanding ratio are quite different with respect to the hole condition. The hole expanding ratio of a punched specimen is much smaller than that of a reamed one due to the difference of surface roughness and internal defects. For the thorough investigation of those effects, tensile tests of a specimen with a hole are performed. The fracture strain is obtained with different hole conditions and a finite element analysis of the hole flanging process carried out. The experimental results are confirmed and reevaluated by finite element analysis of the hole flanging process with ductile fracture criterion proposed.

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Implementing an ERP Customizing Using Process Models and Business Components (프로세스 모델과 비즈니스 컴포넌트를 이용한 ERP 커스터마이징 구현)

  • 박지현;윤기송
    • The Journal of Society for e-Business Studies
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    • v.7 no.1
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    • pp.129-140
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    • 2002
  • To succeed in ERP construction, the purpose of ERP setup must be completed. To accomplish this end, it is required to analysis business process completely and make a plan in detail. For ERP providers', they must support a characterized ERP construction methodology and lower the construction cost by improving an ERP package by making it easy to customize. But, because imported EHP products that are supplied currently are designed for the standard and the rationality, they have a limit to support custom processes of domestic companies. On the contrary, ERP products by domestic companies are unable to support a consistent methodology of constructing ERP system. This is a main reason why much time and costs are consumed than that of an original plan. For solving the problems, ERP packages should provide a consistent process modeling methodology and a modeling tool which can support this methodology. Furthermore, customizing cost must be lowered by implementing reusable components from the process models. This Paper describes a component-based ERP Package system which has peculiar modeling tools and development tools. We describe the modeling methodology and the business component definition of the ERP system. Finally, we describe its customizing process based on these process designs and business components.

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Correlation between Protein Methylation and Hepatotoxicity (단백질메칠화 반응과 간독성간의 상관관계)

  • 김재현;박창원;이주한;백윤기;문화회;홍성렬;이향우
    • Biomolecules & Therapeutics
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    • v.2 no.1
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    • pp.47-53
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    • 1994
  • The methylation response as well as the level of methyl donor substance, 5-adenosyl-L-methionine (SAM) has been suggested to be related to hepatotoxicity including hepatocarcinogenesis. But direct correlation between protein methylation and hepatotoxicity has not been established to the present. To observe relationship between protein methylation and short-term hepatotoxicity induced by chemical substances, the activities of protein methylase I and II (PM I, PM II) were examined in cytosolic fraction of SD rat treated orally with acetaminophen(AA), $\alpha$-naphtyl-isothiocyanate (ANIT) and tetracycline (TC) that was known to produce necrosis, cholestasis and steatosis respectively. To evaluate the degree of hepatotoxicity induced by each chemicals, we observed the serum levels of indicative parameters and histopathological alteration. In AA treated group, the activities of PM I were increased at 6, 12 hours after administration, prior to the appearance of the hepatotoxicity by clinical parameters. It was suggested that the levels of PM I were related with the initial stage of hepatotoxic mechanism induced by AA. In ANIT treated group, though most of clinical parameters were significantly increased at 24, 48 hours after administration, the activity of PM I was not changed, indicating that ANIT induced hepatotoxicity was not coupled to protein methylation.

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Effect of Support in HI Decomposition Reaction using Pt Catalyst (Pt 촉매를 이용한 HI분해반응에서 지지체에 따른 영향)

  • Ko, Yun-Ki;Park, Chu-Sik;Kang, Kyoung-Soo;Bae, Ki-Kwang;Kim, Young-Ho
    • Transactions of the Korean hydrogen and new energy society
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    • v.22 no.4
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    • pp.415-423
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    • 2011
  • HI decomposition step certainly demand catalytic reaction for efficient production of hydrogen in SI process. Platinum catalyst can apply to HI decomposition reaction as well as hydrogenation or dehydrogenation. Generally, noble metal is used as catalyst which is loaded form for getting high dispersion and wide active area. In this study, Pt was loaded onto zirconia, ceria, alumina, and silica by impregnation method. HI decomposition reaction was carried out under the condition of $450^{\circ}C$, 1atm, and $167.76h^{-1}$ (WHSV) in a fixed bed reactor for measuring catalytic activity. And property of a catalyst was observed by BET, TEM, XRD and chemisoption analysis. On the basis of experimental results, we discussed about conversion of HI according to physical properties of the loaded Pt catalyst onto each support.

Prediction of fracture in hub-hole expansion process using ductile fracture criteria (연성 파괴 기준을 이용한 허브 홀 확장 과정에서의 파단 예측)

  • Ko Y. K.;Lee J. S.;Huh H.;Kim H. K.;Park S. H.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2004.10a
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    • pp.160-163
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    • 2004
  • The hub hole in a wheel of vehicles usually formed with hole expansion process. Formability of material, especially the hole expansion ratio, is important to produce a fine hub hole. The hub hole expansion process is different from general forming process or bore expansion process in the viewpoint of forming a thick plate. In the hole expansion process of the plate with a hole, as the hole being expanded, the crack is occurred to outward direction at the boundary of a hole. Therefore, it is need to apply the fracture criterion in the hub hole expansion process. In this paper, the hub hole expansion process is simulated with commercial elasto-plastic finite element code, LS-DYNA3D considering some ductile fracture criteria. Fracture mode and hole expansion ratio is compared with respect to the fracture criteria. Analysis results demonstrate that only the effective plastic strain is not adequate to predict the fracture mode in the hub hole. And the analysis results also indicate that the ductile fracture criteria properly predict the fracture mode but hole expansion ratio is different with the result of each other because of their different characteristics.

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A Study on Hardware Implementation of 128-bit LEA Encryption Block (128비트 LEA 암호화 블록 하드웨어 구현 연구)

  • Yoon, Gi Ha;Park, Seong Mo
    • Smart Media Journal
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    • v.4 no.4
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    • pp.39-46
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    • 2015
  • This paper describes hardware implementation of the encryption block of the '128 bit block cipher LEA' among various lightweight encryption algorithms for IoT (Internet of Things) security. Round function blocks and key-schedule blocks are designed by parallel circuits for high throughput. The encryption blocks support secret-key of 128 bits, and are designed by FSM method and 24/n stage(n=1, 2, 3, 4, 8, 12) pipeline methods. The LEA-128 encryption blocks are modeled using Verilog-HDL and implemented on FPGA, and according to the synthesis results, minimum area and maximum throughput are provided.

PAPR Reduction using Partial Transmit Sequences with Side Information of feedback Type (궤환형 부가정보를 사용하는 PTS 기법의 PAPR 감소)

  • 윤기후;이준서;유흥균;박진수
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.14 no.4
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    • pp.330-335
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    • 2003
  • PTS(partial transmit sequences) has been widely studied for reducing the PAPR of OFDM signal, since it is flexible and any spectral regrowth may not occurred. A drawback of this PTS method should transmit the side information of the optimized phase factor for correct OFDM symbol recovery. A new idea of this paper is to insert the feedback type side information in the conventional PTS method. The simulation results show that the proposed scheme has the same PAPR reduction performance as the conventional PTS without side information and OFDM data are correctly recovered to get the required BER. Also, this method is independent of the channel characteristics and can be easily realized.