• Korean Journal of Soil Science and Fertilizer
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• v.20 no.4
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• pp.359-367
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• 1987

A method for evaluating bacterial chemotactic responses toward several single of combined sugars and sterile mucilage from the different rice cultivars had been tested. Bacterial genus of Azospirillum, Pseudomonas and Agrobacterium were specially identified from the histosphere of different rice cultivars and graminea grasses in saline and reclaimed saline paddy soil. To evaluate chemotaxis of these strains a modification of Fendrik channel method was used. Under this condition Azospirillum lipoferum Ecc 3-1 reacted stereoisomerically fomulating the single migration ring while Agrobacterium radiobacter Ecc 1-1 and Pseudomonas sp Ecc 4-1 did not. Strains specificities of chemotaxis to the single sugar such as D(+)-glucose and D(+)-fructose were less prominent than malic and citric acid. Chemotactic responses to the combined sugar such as D-galacturonic acid and the L-aspartate were found high attracting reaction than other combined sugars. Chemotaxis of associative $N_2$-fixing bacteria to the root exudates of different rice cultivars were differed among bacterial strains and rice cultivars.

• Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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• 2002.11a
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• pp.306-310
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• 2002

이동 통신의 급격한 발달로 다양한 부가가치서비스가 등장하고, 이러한 서비스를 좀더 편리하고 안전하게 사용하고 싶어하는 사용자와 부가가치서비스를 제공하는 VASP(Value -Added Service Provider) 사이의 보안이 필수적인 것이 되었다. 이를 위하여 이동 통신 환경의 한계인 제한된 자원과 제한된 계산력을 극복할 수 있도록 적은키 길이를 가지고 보다 안전한 서비스를 제공할 수 있는 타원곡선 암호시스템(ECC)를 기반으로 하여 부가가치서비스에 효율적인 인증 및 키 합의 프로토콜을 제안하고, 차세대 이동통신시스템에 적용해본다.

• Proceedings of the Korea Multimedia Society Conference
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• 2002.11b
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• pp.163-166
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• 2002

무선 인터넷 사용의 증가와 함께 PDA 또는 무선단말기와 같은 제한된 시스템 환경에 적합한 보안 서비스의 필요성이 증가되고 있다. 무선환경을 위해 제공되어야 할 다양한 보안 서비스 중 인증 및 키 합의를 위한 과정은 보안상 매우 민감한 부분이다. 안전한 프로토콜 설계에서 통신에 참여하는 개체들에 대한 인증 및 이후 진행되는 해당 세션의 안전성 확보를 위한 세션키 설정, 서비스 사용자에 대한 익명성 보장 등이 고려되어야 한다. 본 논문에서는 무선 인터넷의 한정된 시스템 환경을 고려한 타원 곡선 암호시스템(ECC) 기반의 인증 및 키 합의 프로토콜을 제안한다.

• Proceedings of the IEEK Conference
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• 2001.06b
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• pp.305-308
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• 2001

This paper describes the design of elliptic curve cryptographic (ECC) coprocessor over binary fields for the If card. This coprocessor is implemented by the shift-and-add algorithm for the field multiplication algorithm. And the modified almost inverse algorithm(MAIA) is selected for the inverse multiplication algorithm. These two algorithms is merged to minimize the hardware size. Scalar multiplication is performed by the binary Non Adjacent Format(NAF) method. The ECC we have implemented is defined over the field GF(2$^{163}$), which is a SEC-2 recommendation［7］..

• Information and Communications Magazine
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• v.32 no.6
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• pp.16-22
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• 2015

NAND flash 메모리의 집적도를 높이기 위한 주요 기술로, 데이터가 저장되는 cell 자체의 크기를 줄여주는 미세 공정화와 cell 당 저장되는 정보량을 늘려주는 멀티-레벨(multi-level)화가 사용되고 있다. 이러한 기술의 적용은 NAND flash 메모리 자체의 오류를 증가시키게 되므로, NAND flash 메모리 기반 데이터 저장 장치의 신뢰성을 높은 수준으로 유지하기 위해서는 우수한 정정 능력을 갖는 ECC(error control code) 를 사용하는 것이 필수적이다. 본고에서는 NAND flash 메모리의 신뢰성 특성과 함께 NAND flash 메모리를 사용하는 데이터 저장 장치에서의 ECC의 응용에 대해서 살펴보고자 한다.

• Proceedings of the Optical Society of Korea Conference
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• 2001.02a
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• pp.64-65
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• 2001

HDDS(Holographic Digital Data Storage) 시스템에서 저장밀도가 증가함에 따라서 기록/재생된 데이터는 중첩된 페이지 사이의 간섭과 인접 픽셀간의 간섭에서 기인하는 ISI (Intersymbol Interference) 및 Speckle 잡음을 포함하는 Random Noise와 광학 수차, 광학정렬 오차 및 Laser 광원의 비균일 광강도 분포 등에서 기인하는 Non- random Noise 등 다양한 시스템 잡음에 의해서 BER 이 급격히 저하되는 문제가 발생된다. 113 이러한 문제점을 해소하고 시스템의 기록/재생 데이터 신뢰도를 확보하기 위해서는 적절한 광신호처리 기법과 coding 기법이 도입되어야만 한다. (중략)

• ETRI Journal
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• v.32 no.3
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• pp.362-369
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• 2010

While the elliptic curve cryptosystem (ECC) is getting more popular in securing numerous systems, implementations without consideration for side-channel attacks are susceptible to critical information leakage. This paper proposes new power attack countermeasures for ECC over Koblitz curves. Based on some special properties of Koblitz curves, the proposed methods randomize the involved elliptic curve points in a highly regular manner so the resulting scalar multiplication algorithms can defeat the simple power analysis attack and the differential power analysis attack simultaneously. Compared with the previous countermeasures, the new methods are also noticeable in terms of computational cost.

• Journal of Radiation Protection and Research
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• v.20 no.1
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• pp.53-64
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• 1995

The radiation fields following the large loss of coolant accident (LOCA) have been assessed for the vital areas in the service building of Wolsong 2, 3, and 4 nuclear power plants. The ORIGEN2 code was used in calculating the fission product inventories in the fuel. The source terms were based upon the activity released following the dual failure accident scenario, i.e., a LOCA followed by impaired emergency core cooling (ECC). Configurations of the reactor building, the service building, and the ECC system were constructed for the QAD-CG calculations. The dose rates and the time-integrated doses were calculated for the time period of upto 90 days after the accident. The results showed that the radiation fields in the vital access areas were found to be sufficiently low. Some areas however showed relatively high radiation fields that may require limited access.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2008.11a
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• pp.199-203
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• 2008

With recent trend in domestic and global market requiring architectures' conversion into skyscrapers seasoned with the features of landmarks, structural problems in relation with explosive spatting during fire emergencies are arising as controversial issues. Accordingly, many productive researches have been made in relation to the reinforcement techniques for improving fire resistance and the number of applications in the field is gradually increasing. In this study, a ductile outline form using ECC (Engineered Cementations Composites) was made with improvements on the structure and fire resistance to examine its applicability. Also, currently in Japan, the number of studies and applications is increasing focusing on reduction of construction time and improvement of workability with application of Half-PCa method. However, using such method of construction, large structural members decrease the utilization of space and architecture-wise, there is a disadvantage of the weight increase. Therefore, in such context, it would be worth reducing the weight of the structural members by reducing the size using ECC. In addition, its excellent pseudo strain-hardening due to fiber may have great effects on seismic designs. In the mean time, this study planned 3 equal conditions for mix water, PVA fiber and additives excluding binder and refractory to evaluate the mechanical properties of resistance against pressure and internal force. Finally, an evaluation was executed on the fire resistance of the newly made ductile outline form. As a result, from ECC-I to ECC-III, all showed excellent mechanical properties due to pseudo strain-hardening and in the fire resistance test conducted with ISO 834 heating curve, most of them tended to be in the range of the reference temperature (538℃-180min), so there was no occurrence of any explosive spatting.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.5C
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• pp.726-736
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• 2004

In this paper, we proposed a new scalar multiplier structure needed for an elliptic curve cryptosystem(ECC) over the standard basis in GF(2$^{163}$ ). It consists of a bit-serial multiplier and a divider with control logics, and the divider consumes most of the processing time. To speed up the division processing, we developed a new division algorithm based on the extended Euclid algorithm. Dynamic data dependency of the Euclid algorithm has been transformed to static and fixed data flow by a localization technique, to make it independent of the input and field polynomial. Compared to other existing scalar multipliers, the new scalar multiplier requires smaller gate counts with improved processor performance. It has been synthesized using Samsung 0.18 um CMOS technology, and the maximum operating frequency is estimated 250 MHz. The resulting performance is 148 kbps, that is, it takes 1.1 msec to process a 163-bit data frame. We assure that this performance is enough to be used for digital signature, encryption/decryption, and key exchanges in real time environments.