• Title/Summary/Keyword: Seed structure

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VLSI Design of Cryptographic Processor for SEED and Triple DES Encryption Algorithm (SEED 와 TDES 암호 알고리즘을 구현하는 암호 프로세서의 VLSI 설계)

  • 정진욱;최병윤
    • Proceedings of the IEEK Conference
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    • 2000.06b
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    • pp.169-172
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    • 2000
  • This paper describes design of cryptographic processor which can execute SEED, DES, and triple DES encryption algorithm. To satisfy flexible architecture and area-efficient structure, the processor has I unrolled loop structure with hardware sharing and can support four standard mode, such as ECB, CBC, CFB, and OFB modes. To reduce overhead of key computation, the precomputation technique is used. Also to eliminate increase of processing time due to data input and output time, background I/O technique is used which data input and output operation execute in parallel with encryption operation of cryptographic processor. The cryptographic processor is designed using 2.5V 0.25 $\mu\textrm{m}$ CMOS technology and consists of about 34.8K gates. Its peak performances is about 250 Mbps under 100 Mhz ECB SEED mode and 125 Mbps under 100 Mhz triple DES mode.

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A White-box Implementation of SEED

  • Kim, Jinsu
    • Journal of Advanced Information Technology and Convergence
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    • v.9 no.2
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    • pp.115-123
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    • 2019
  • White-box cryptography is an implementation technique in order to protect secret keys of cryptographic algorithms in the white-box attack model, which is the setting that an adversary has full access to the implementation of the cryptographic algorithm and full control over their execution. This concept was introduced in 2002 by Chow et al., and since then, there have been many proposals for secure implementations. While there have been many approaches to construct a secure white-box implementation for the ciphers with SPN structures, there was no notable result about the white-box implementation for the block ciphers with Feistel structure after white-box DES implementation was broken. In this paper, we propose a secure white-box implementation for a block cipher SEED with Feistel structure, which can prevent the previous known attacks for white-box implementations. Our proposal is simple and practical: it is performed by only 3,376 table lookups during each execution and the total size of tables is 762.5 KB.

Soil salinity shifts the community structure and diversity of seed bacterial endophytes of salt-sensitive and tolerant rice cultivars

  • Walitang, Denver I.;Ahmed, Shamim;Jeon, Sunyoung;Pyo, Chaeeun;Sa, Tongmin
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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    • pp.244-244
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    • 2017
  • Soil salinity due to accumulation of salts particularly sodium chloride affects agricultural lands and their vegetation. Generally, rice is a moderately sensitive plant with some cultivars with varying tolerance to salinity. Though there are physiological differences between salt-sensitive and salt-tolerant rice cultivars, both are still affected especially during high salinity and prolonged exposure. This also ultimately affects their indigenous bacterial endophytes particularly those that inhabit the rice seed endosphere. This study investigates the dynamic structure of seed bacterial endophytes of salt-sensitive and tolerant rice cultivars grown in different levels of soil salinity. Endophytic bacterial diversity was studied Terminal-Restriction Fragment Length Polymorphism (T-RFLP) analysis. Results revealed a very interesting pattern of diversity and shifts in community structure of bacterial endophytes in the rice seeds. There is a general decrease in diversity for the salt-sensitive rice cultivar, IR29 as soil salinity increases. For the salt-tolerant cultivars, IC32 and IC37, diversity interestingly increased at moderate salinity then decreased at high soil salinity. The patterns of community structure is also strikingly different for the salt-sensitive and salt-tolerant rice cultivars. IR29 has a more even distribution of abundance, but under soil salinity, the community shifted where Curtobacterium, Pantoea, Flavobacterium and Microbacterium become the more dominant bacterial communities. For IC32 and IC37, the dominant bacterial groups under normal stress conditions were also the dominant bacterial groups during salt stress conditions. Their seed bacterial community is dominated by endophytes belonging to Microbacterium, Flavobacterium, Pantoea, Kosakonia and Enterobacter. Stenotrophomonas and Xanthomonas have not changed in terms of abundance under different salinity stress level in the salt-sensitive and salt-tolerant rice cultivars. This study showed that soil salinity greatly influenced the seed bacterial communities of rice seeds irrespective of their physiological tolerance to salinity.

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Taxonomic Implications of Seed Coat in the Subtribe Calthinae (Ranunculaceae) (미나리아재비과 동의나물아족의 종피형태와 분류학적 검토)

  • Heo, Kweon;Suh, Youngbae
    • Korean Journal of Plant Taxonomy
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    • v.38 no.1
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    • pp.1-16
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    • 2008
  • Anatomical features of seed coat were examined on Trollius, Calathodes, and Caltha of Ranunculaceae to evaluate the taxonomic circumscription of Megaleranthis saniculifolia, which is monotypic and endemic in Korea. Megaleranthis saniculifolia showed the exotestal type of seed coat exhibiting a well-developed palisade structure in exotesta and its external surface of exotesta cells was concave. On the other hand, the shape of exotesta cells in Caltha was cuboidal and the outer surface was smooth. The exotesta of Calathodes seeds was formed of the palisade structure like M. saniculifolia, but the outer surface of exotesta cells was smooth. The palisade structure was much better developed in the exotesta of Calathodes as well as Megaleranthis seeds than in the exotesta of Trollius seeds. The outer surface of exotesta cells in Trollius was either convex or concave according to the species examined. Since the genera of the subtribe Calthinae of the family display differences in seed sculpturing and the anaotmy of seed coat, these characteristics are useful to access taxonomic relationships among them. The morphological and anatomical features of seed coat suggest that Megaleranthis be possibly allied with Trollius rather than Caltha or Calathodes. Concave surface of seed coat cells and well-developed palisade structure of exotesta are shared by M. saniculifolia and some species of Trollius in common.

Y2BaCuO4 Segregarion , a Possibility of Multi-Seeding and the Origin of Diagonal Line in YBa2Cu3O7-$\delta$ Superconductor Single Crystal (YBa_{2}Cu_{3}O_{7-\delta} 고온초전도체 단결정에서의 Y_{2}BaCuO_{5} 편석과 Multi-Seeding의 가능성, 대각선 흔적의 형성 원인)

  • 성현태
    • Progress in Superconductivity and Cryogenics
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    • v.1 no.1
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    • pp.1-6
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    • 1999
  • The microstructures of top seed mult processde $\textrm{YBa}_2\textrm{Cu}_3\textrm{O}_7$.$\delta$ single crystal were studied. Although shape of the seed was not faceted. the growth shape of Y123 single crystal was faceted. It was observed that Y211 phases were trapped in specific spaces of the faceted region. From the microstructural investigation. it was suggested that the segregation of Y211 is due to the difference of growth rates in crystal direction. When a single crystal was grown by the single seed with stepped multi surfaces. a microstrue was grown from multi-seed. The microstructure show the possibility of multi-seed growth. Corn kernel like structure without Y211 phase was observed and seemed to be formed by the diffusion reaction between Y211 phase in crystal and liquid wetted on the crystal. the diagonal line on Y123 crystal was observed that it was formed by the corn kernel like structure.

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Characterization of Poly-Si TFT's using Amorphous-$Si_xGe_y$ for Seed Layer (Amorphous-$Si_xGe_y$을 seed layer로 이용한 Poly-Si TFT의 특성)

  • Jung, Myung-Ho;Jung, Jong-Wan;Cho, Won-Ju
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2007.06a
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    • pp.125-126
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    • 2007
  • Polycrystalline silicon thin-film-transistors (Poly-Si TFT's) with a amorphous-$Si_xGe_y$ seed layer have been fabricated to improve the performance of TFT. The dependence of crystal structure and electrical characteristics on the the Ge fractions in $Si_xGe_y$ seed layer were investigated. As a result, the increase of grain size and enhancement of electrical characteristics were obtained from the poly-Si TFT's with amorphous-SixGey seed layer.

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Effects of Plasma Pretreatment of the Cu Seed Layer on Cu Electroplating (Cu seed layer 표면의 플라즈마 전처리가 Cu 전기도금 공정에 미치는 효과에 관한 연구)

  • O, Jun-Hwan;Lee, Seong-Uk;Lee, Jong-Mu
    • Korean Journal of Materials Research
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    • v.11 no.9
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    • pp.802-809
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    • 2001
  • Electroplating is an attractive alternative deposition method for copper with the need for a conformal and conductive seed layer In addition, the Cu seed layer should be highly pure so as not to compromise the effective resistivity of the filled copper interconnect structure. This seed layer requires low electrical resistivity, low levels of impurities, smooth interface, good adhesion to the barrier metal and low thickness concurrent with coherence for ensuring void-free fill. The electrical conductivity of the surface plays an important role in formation of initial Cu nuclei, Cu nucleation is much easier on the substrate with higher electrical conductivities. It is also known that the nucleation processes of Cu are very sensitive to surface condition. In this study, copper seed layers deposited by magnetron sputtering onto a tantalum nitride barrier layer were used for electroplating copper in the forward pulsed mode. Prior to electroplating a copper film, the Cu seed layer was cleaned by plasma H$_2$ and $N_2$. In the plasma treatment exposure tome was varied from 1 to 20 min and plasma power from 20 to 140W. Effects of plasma pretreatment to Cu seed/Tantalum nitride (TaN)/borophosphosilicate glass (BPSG) samples on electroplating of copper (Cu) films were investigated.

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A Study on Improvement Direction of G-SEED for Existing Buildings (기존 건축물의 녹색건축인증 개선방향에 대한 연구)

  • Hyun, Eun-Mi;Lee, Jae-Eun;An, Kwang-Ho
    • Journal of the Architectural Institute of Korea Structure & Construction
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    • v.34 no.5
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    • pp.59-67
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    • 2018
  • G-SEED's evaluation of existing buildings is an important point because the energy consumption and CO2 emissions of existing buildings are continuously increasing due to the aging of buildings over time. However, as G-SEED certification is concentrated on new buildings and the standards are not yet available, we will make improvements to evaluate the existing buildings of G-SEED. In order to improve G-SEED for EB, two research procedures were carried out. First, LEED EBOM and LEED for NC compare and analyze evaluation items and methods, and LEED EBOM focuses on evaluation of existing buildings. Second, we analyzed the certification evaluation contents of eight domestic LEED EBOM accredited buildings and obtained items that can be applied or need to be applied when revising G-SEED for EB. LEED EBOM is focused on improving the performance and utilization of data that track and manage the energy and environmental effects of building operations. As a result of the case analysis, the evaluation of G-SEED for EB requires quantitative evaluation items such as environmental management of buildings, energy performance status of building, improvement plan and improvement of performance according to tracking value. Although G-SEED for EB is not structured yet and there are few cases of certification, it is expected that quantitative evaluation of existing buildings will be made through continuous research.

An Encryption Algorithm Based on Light-Weight SEED for Accessing Multiple Objects in RFID System (RFID 시스템에서 다중 객체를 지원하기 위한 경량화된 SEED 기반의 암호화 알고리즘)

  • Kim, Ji-Yeon;Jung, Jong-Jin
    • Journal of Korea Society of Industrial Information Systems
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    • v.15 no.3
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    • pp.41-49
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    • 2010
  • Recently, RFID systems are spreading in various industrial areas faster but cause some serious problems of information security because of its unstable wireless communication. Moreover, traditional RFID systems have a restriction that one tag per each application object. This restriction deteriorates their usability because it is difficult to distinguish many tags without some kind of effort. Therefore, efficient information sharing of objects based on information security has to be studied for more spreading of RFID technologies. In this paper, we design a new RFID tag structure for supporting multiple objects which can be shared by many different RFID applications. We also design an encryption/decryption algorithm to protect the identifying information of objects stored in our tag structure. This algorithm is a light revision of the existing SEED algorithm which can be operated in RFID tag environment. To evaluate the performance of our algorithm, we measure the encryption and decryption times of this algorithm and compare the results with those of the original SEED algorithm.

Seed-dependent Accelerated Fibrillation of ${\alpha}$-Synuclein Induced by Periodic Ultrasonication Treatment

  • Kim, Hyun-Jin;Chatani, Eri;Goto, Yuji;Paik, Seung-R.
    • Journal of Microbiology and Biotechnology
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    • v.17 no.12
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    • pp.2027-2032
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    • 2007
  • [ ${\alpha}$ ]-Synuclein is the major component of Lewy bodies and responsible for the amyloid deposits observed in Parkinson's disease. Ordered filamentous aggregate formation of the natively unfolded ${\alpha}$-synuclein was investigated in vitro with the periodic ultrasonication. The ultrasonication induced the fibrillation of ${\alpha}$-synuclein, as the random structure gradually converted into a ${\beta}$-sheet structure. The resulting fibrils obtained at the stationary phase appeared heterogeneous in their size distribution, with the average length and height of $0.28\;{\mu}m{\pm}0.21\;{\mu}m$ and $5.6\;nm{\pm}1.9\;nm$, respectively. After additional extensive ultrasonication in the absence of monomeric ${\alpha}$-synuclein, the equilibrium between the fibril formation and its breakdown shifted to the disintegration of the preexisting fibrils. The resulting fragments served as nucleation centers for the subsequent seed-dependent accelerated fibrillation under a quiescent incubation condition. This self-seeding amplification process depended on the seed formation and subsequent alterations in their properties by the ultrasonication to a state that accretes the monomeric soluble protein more effectively than their reassociation of the seeds back to the original fibrils. Since many neurodegenerative disorders have been considered to be propagated via the seed-dependent amyloidosis, this study would provide a novel aspect of the significance of the seed structure and its properties leading to the acce]erated amyloid formation.