• 대한수학회지
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• 제56권2호
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• pp.539-558
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• 2019

An ideal of a commutative ring is called a d-ideal if it contains the annihilator of the annihilator of each of its elements. Denote by DId(A) the lattice of d-ideals of a ring A. We prove that, as in the case of f-rings, DId(A) is an algebraic frame. Call a ring homomorphism "compatible" if it maps equally annihilated elements in its domain to equally annihilated elements in the codomain. Denote by $SdRng_c$ the category whose objects are rings in which the sum of two d-ideals is a d-ideal, and whose morphisms are compatible ring homomorphisms. We show that $DId:\;SdRng_c{\rightarrow}CohFrm$ is a functor (CohFrm is the category of coherent frames with coherent maps), and we construct a natural transformation $RId{\rightarrow}DId$, in a most natural way, where RId is the functor that sends a ring to its frame of radical ideals. We prove that a ring A is a Baer ring if and only if it belongs to the category $SdRng_c$ and DId(A) is isomorphic to the frame of ideals of the Boolean algebra of idempotents of A. We end by showing that the category $SdRng_c$ has finite products.

• 대한화학회지
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• 제13권2호
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• pp.141-147
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• 1969

Organophosphorous compounds can be reduced by zinc metal in acidic solution after alkaline hydrolysis. Although phosphates and phosphonates did not evolve any gas, dithioates did evolve hydrogen sulfide and phosphine, thionates and thiolates did evolve only hydrogen sulfide. The evolved gases were qualitatively detected by means of lead acetate and silver nitrate or mercuric bromide papers and determined by spectrophotometrically. The reduction mechanism and analytical method of dithioates were proposed.

• 한국환경보건학회지
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• 제18권2호
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• pp.117-124
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• 1992

Pretreatment with low concentration of Bleomycin and Cadmium rendered Chinese Hamster Ovary Cells more resistant to the induction of chromosome aberration by subsequent high concentration of same agent, however Mitomycin C did not function in that way. The cells pre-exposed to low dose of Cadmitim did not show cross-resistance to challenge dose of Mitomycin C for the induction of chromosome aberration, but cells pre-exposed to Bleomycin showed cross resistance. And the cells pre-exposed to low dose of Mitomycin C showed cross resistance to challenge of Bleomycin, but Cadmium did not.

• 대한가정학회지
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• 제42권2호
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• pp.177-193
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• 2004

Using data from the 2001 Computer and Internet Use Survey by the National Statistical Office, this study investigated digital divide among women aged between 20 and 55. Following were the major findings. first, two-thirds of women did not use Internet even though many of these had Internet access at home. Second, those who did not have Internet access at home, those with a lower level of educational attainment, those with blue color or service occupations, and those with higher age were less likely to use Internet than their counterparts in these socio-economic variables. Third, expanding Internet infrastructure would not improve Internet use of the Elderly. Forth, the majority of those who did not use Internet did not recognize the Internet itself. Based on the result the policy implications for digital divide were suggested.

• 한국멀티미디어학회논문지
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• 제24권6호
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• pp.760-767
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• 2021

The identity verification is one of the most important technologies in online services. Many services in society are provided online, and the service is provided after confirming the user's identity. Users can do a lot of things online, but they also have side effects. Online digital information is easily manipulated and it is difficult to verify its authenticity, causing social confusion. Accordingly, there has been a movement for individuals to directly manage their identity information using DID. In this paper, we propose a system that can authenticate identity by directly adding own personal information and issuing an identifier using DID technology based on a private blockchain. Then, to verify the proposed system, the scenario is executed and verified.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2020년도 춘계학술발표대회
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• pp.417-419
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• 2020

데이터 3법 시대에 접어들면서 기업들에는 가명화된 개인정보를 활용할 수 있는 길이 열렸다. 하지만 현 데이터 3법은 데이터를 생성하고 유통하며 활용할 기업들의 책임과 혜택에 내용이 맞춰져 있어 아쉬운 감이 있다. 개인의 기본권을 보장하면서도 마이데이터 유통 및 활용을 도울 방법은 없을까? 본 논문에서는 데이터의 주체인 개인이 데이터 주권을 행사하고 실질적인 혜택을 받는 마이데이터 서비스의 활성화를 위한 ID 관리 기술로 블록체인 기반 분산 ID(Decentralized Identification, DID)를 제안하고, DID 수용의도에 영향을 마치는 요인을 연구함으로써 마이데이터 서비스 개발 활성화를 위한 정책적, 실무적 시사점을 도출하고자 한다.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2021년도 추계학술발표대회
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• pp.322-325
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• 2021

자율주행 자동차는 최근 들어 비약적인 발전을 거듭하고 있지만, 동시에 V2V, V2I 등 차량의 네트워킹에 따른 보안 문제에 대한 중요도 또한 함께 올라가고 있다. 이에 대비책으로 SCMS 를 중심으로 보안 기술이 발전하고 있지만, 중앙 데이터베이스에 대한 의존도는 여전히 높아 한 번의 보안 사고에도 심각한 피해가 우려되는 상황이다. 본 논문은 이러한 상황을 방지하기 위해 블록체인의 DID(Decentralized Identify, 탈중앙화 신원증명) 기술을 적용하는 방안을 설명하고, 그 예시로 긴급 차량에서의 DID 활용 방안을 제안한다.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 1999년도 춘계학술대회 논문집
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• pp.298-299
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• 1999

• Archives of Pharmacal Research
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• 제23권1호
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• pp.72-78
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• 2000

The general pharmacological properties of YJA20379-1 2-dimethylamino-4,5-dihydrothiazolo[4,5:3,4]pyridol[1,2-a]benzoimidazole, a novel proton pump inhibitor with antiulcer activities were investigated in mice, rats, guinea pigs and rabbits. YJA20379-2 at oral doses of 50, 100 and 200 mg/kg did not affect the general behaviour, hexobarbital hypnosis and motor coordination in mice. The drug did not have analgesic or anticonvulsant action at 200 mg/kg. Locomotor activity and body temperature were not influenced at 100 mg/kg. At a concentration up to 2{\times}10^{-4} g/ml$, YJA20379-2 did not produce any contraction or relaxation of isolated preparations, such as the rat fundus, the guinea pig ileum and the rat uterus, and did not antagonize the contractile response to several spasmogens, such as histamine, acetylcholine, serotonin and oxytocin. At dosages up to 200 mg/kg p.o. YJA20379-2 did not affect the pupil size of mice. Intestinal propulsion of mice was not affected up to 200 mg/kg p.o. and the drug did not affect urinary excretion at 100 mg/kg p.o. These results indicate that at dosages up to 100 gm/kg p.o. YJA20379-2 was found not to affect this pharmacological profile. However, at 200 mg/kg the drug lowered body temperature and showed decreased in locomotor activity and urine volume.

• 벤처혁신연구
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• 제2권2호
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• pp.21-29
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• 2019

한국에서 흔히 사용하는 공인인증서 기술에서 사용자들은 그 비밀번호를 기억하지 못했을때 항상 다시 설정해야하는 번거로운 문제점을 지니고 있다. 본 논문에서는 이 문제점에 대한 해결책으로 분산저장을 위한 블록체인과 PKI, DID를 활용하여 안전한 공인인증서 암호 복구 프로토콜을 제안한다. DID는 블록체인 시스템에서 블록 ID를 보호하기 위한 스키마이다. PKI에서 사용되는 개인키를 사용자의 생체인식, 예를 들어 지문으로 하여 복잡한 개인키를 기억하는 것을 완벽히 대체할 수 있도록 구성한다. 이를 위해, 현재 대부분의 사용자들이 이용하는 스마트폰에 탑재된 FIDO 인증 기술을 기반으로 블록 내부 데이터에 접근하기 위해 사용자를 인증하는 과정을 거쳐 공격자가 데이터를 탈취하는 위험성을 최소화 한다.