• The Journal of the Korea institute of electronic communication sciences
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• v.5 no.4
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• pp.412-417
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• 2010

In this paper, we analyze the properties of nonlinear sequence generated by the shrinking generator. Also we propose a method for recovering the original sequence from intercepted bits by analyzing phase shifts of the output sequence using the properties of sequences generated from control register.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.11
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• pp.2507-2513
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• 2010

In this paper, we show that the shrinking generator with two LFSR whose characteristic polynomials are primitive is an interleaving generator and analyze phase shifts in shrunken sequence. Also for a given intercepted sequence of shrunken sequence, we propose. the method of reconstructing some deterministic bits of the shrunken sequence using phase shifts.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.10
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• pp.2283-2291
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• 2010

The shrinking generator which is one of clock-controlled generator is a very simple generator with good cryptographic properties. A nonlinear sequence generator based on two 90/150 maximum length cellular automata can generate pseudorandom sequences at each cell of cellular automata whose characteristic polynomials are same. The nonlinear sequence generated by cellular automata has a larger period and a higher linear complexity than shrunken sequence generated by LFSRs. In this paper we analyze shrunken-interleaved sequence based on 90/150 maximum length cellular automata. We show that the sequence generated by nonlinear sequence generator based on cellular automata belongs to the class of interleaved sequence. And we give an effective algorithm for reconstructing unknown bits of output sequence based on intercepted keystream bits.

• The Journal of the Korea institute of electronic communication sciences
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• v.11 no.9
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• pp.885-892
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• 2016

The nonlinear sequence generator called the shrinking generator was designed as nonlinear keystream generator composed by two maximum-length LFSRs. The shrunken sequences generated by the shrinking generator are included in the class of interleaved sequences and can be modelled as one of the output sequences of cellular automata (CA). In this paper, we propose a method for synthesizing a 90/150 CA-based sequence generator to generate a family of sequences with the same characteristic polynomial as the shrunken sequences.

• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.1
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• pp.179-184
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• 2020

Cellular automata (CA), which is known as a pseudo random number generator due to its excellent randomness, has various applications. Cho et al. designed a CA-based shrinking generator to generate a long period of nonlinear sequence. In addition, chaotic cat maps have been studied by many researchers as the complex nonlinear dynamics systems with sensitivity in initial conditions and unpredictable characteristics. In this paper, we propose a new image encryption method using nonlinear sequence generated by CA-based shrinking generator with maximum period and 3D chaotic cat map for high security.

• Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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• 2002.11a
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• pp.88-91
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• 2002

자기 수축 발생기(self-shrinking generator)는 Meier와 Staffelbach에 의해 제안되었으며[4], 구조가 간단하고 키수열을 생성하는 속도가 빠르기 때문에 스트림 암호시스템으로 각광받고 있다 [5]. 본 논문에서는 자기 수축 발생기의 새로운 구성방법을 제안한다. 제안된 자기 수축 발생기는 하나의 선형귀환회로와 주어진 짝수 m에 의하여 정의되며 일반적으로 선형귀환회로의 귀환다항식으로 원시다항식을 사용한다. 이 경우 키수열은 균형성을 만족하며, 선형귀환회로의 귀환다항식의 차수를 $d_{Y}$ 라고 하면 주기는 $d_{Y-2}$ 이다. m을 $2^{η}$ζ로 표현하면 선형복잡도 Lz는 $d_{Y}$ ＋η-3/$\leq$ $L_{Z}$ $\leq$m/2($d_{Y}$ -1 - ($d_{Y}$ -2))이다. 따라서 제안된 자기 수축 발생기는 기존의 자기 수축 발생기에 비하여 암호학적으로 우수한 성질을 갖는다.다.

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.345-346
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• 2003

폴리아크릴로니트릴을 NaOH로 가수분해시키면 carboxylate anion과 carboxamide기가 생성되며, 물을 흡수할 경우 sodium carboxylate기의 해리로 팽윤이 크게 일어나므로 고흡수성을 지니게 된다[l]. 일반적으로 섬유가 팽윤을 하면 수축하며, 가수분해된 폴리아크릴로니트릴 섬유는 흡수되는 물 속의 염의 농도 또는 pH에 따라 팽윤도가 다르기 때문에 가수분해된 시간과 pH조건 변화에 따라서 수축하는 정도가 다르다. 과거의 연구결과에 의하면 아크릴 섬유는 2M HCI에서 최소의 길이로 수축하며, 2M NaOH에서 최대의 길이가 나타난다고 하였다[2]. (중략)

• Journal of Industrial Convergence
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• v.20 no.7
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• pp.131-137
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• 2022

In the study, we endeavored to assess the convergence effect of Silybum marianum-derived silymarin and epidemiologically-correlated alcohol intake on vascular contractility and to determine the mechanism involved. There were few reports addressing the question whether thin or thick filament modulation is included in ethanol and silymarin-induced regulation. We hypothesized that ethanol at a low concentration and silymarin play a role in agonist-dependent regulation of vascular contractility. Denuded arterial muscles of Sprague-Dawley male rats were suspended in organ baths and isometric tensions were transduced and recorded using isometric transducers and an automatic data acquisition system. Interestingly, both silymarin and ethanol didn't encourage silymarin alone-induced inhibition in agonists-induced contraction suggesting that endothelial nitric oxide synthesis might be involved in ethanol or silymarin-induced modulation of vascular contractility and additional pathways besides endothelial nitric oxide synthesis such as ROCK inactivation might be involved in the silymarin-induced modulation of vascular contractility.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.5A
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• pp.909-915
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• 2006

To predict autogenous shrinkage of concrete, unsaturated pore compensation factor could be calculated by experiments of autogenous shrinkage of cement paste on the assumption that the differences between degree of hydration and strain rate of autogenous shrinkage are unsaturated pore formation rate. Applying unsaturated pore compensation factor on modified Pickket model considering contribution factor and non-contribution factor to autogenous shrinkage of concrete, experimental data and existing model were compared. From the results modified Pickket model was verified to present similar tendency between Tazawa model and experimental data, but CEB-FIP model might be corrected because this model uses ultimate autogenous shrinkage underestimated and the same autogenous time function of concrete material properties considering only compressive strength.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.10a
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• pp.97-98
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• 2001

순환기계 질병의 원인이 되는 동시에 뇌출혈, 심장병 및 신장병 등과 합병증으로 나타날 경우 치사율이 매우 높은 만성 퇴행성 질환인 고혈압의 90％ 이상을 차지하는 본태성 고혈압은 정상적인 혈압을 유지하는 기구들이 천천히 붕괴되어 진행되는 질병이다(Frohlich, 1982). 이러한 본태성 고혈압의 원인 중에서 reninㆍangiotensin계가 혈압조절에 매우 중요한 역할을 한다고 알려지고 있다(Saxena, 1992). 즉, angiotensinogen이 renin의 분해를 받아서 angiotensin I을 생성하는데, 이는 angiotensin converting enzyme(ACE)에 의하여 COOH 말단의 dipeptide가 절단되어 강력한 혈관수축작용을 하는 angiotensin II를 생성한다. (중략)