• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.10a
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• pp.773-775
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• 2013

In this paper, we consider the problem for finding a vertex sequence of the directed cycle graph from the individual neighborhood information on a reconfigurable mesh(in short, RMESH). This problem can be solved in linear time using a sequential algorithm. However, it is difficult to develop a sublinear time parallel algorithm for the problem because of its sequential nature. All kinds of polygons can be represented by directed cycles, hence a solution of the problem may be used to solving problems in which a polygon should be constructed from the adjacency information for each vertex. In this paper, we present a constant time $n{\times}n^2$ RMESH algorithm for the problem with n vertices.

• Geomechanics and Engineering
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• v.13 no.5
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• pp.809-823
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• 2017

This paper describes lab test results of artificial rock-like material samples having a plane joint. Cyclic shear tests were performed under different normal loads and different shear displacement amplitudes. For this purpose, multi-stage normal loading tests (30 kN, 60 kN, 90 kN, 180 kN, 360 kN and 480 kN) with cyclic excitation at frequency of 1.0 Hz and different shear displacement amplitudes (0.5 mm, 1.0 mm, 2.0 mm, 4.0 mm, 5.0 mm, and 8.0 mm) were conducted using the big shear box device GS-1000. Experimental results show, that shear forces increase with the increase of normal forces and quasi-static friction coefficient is larger than dynamic one. With the increase of normal loads, approaching the peak value of shear forces needs larger shear displacements. During each cycle the normal displacements increase and decrease (rotational behavior in every cycle). Peak angle of inclination increases with the increase of normal load. A phase shift between maximum shear displacement and maximum shear force is observed. The corresponding time shift decreases with increasing normal load and increases with increasing shear displacement amplitudes.

• Journal of the Institute of Electronics Engineers of Korea TE
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• v.39 no.1
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• pp.16-21
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• 2002

In this paper, a dual type PFD(Phase Frequency Detector) for high speed PLL to improve output characteristics using TSPC(True Single Phase Clocking) circuit is proposed. The conventional 3-state PFD has problems with large dead-zone and long delay time. Therefore, it is not applicable to high-speed PLL(Phase-Locked Loop). A dynamic PFD with dynamic CMOS logic circuit is proposed to improve these problems. But, it has the disadvantage of jitter noise due to the variation of the duty cycle. In order to solve the problems of previous PFD, the proposed PFD improves not only the dead zone and duty cycle but also jitter noise and response characteristics by the TSPC circuit and dual structured PFD circuit. The PFD is consists of a P-PFD(Positive edge triggered PFD) and a N-PFD(Negative edge triggered PFD) and improves response characteristics to increase PFD gain. The Hspice simulation is performed to evaluate the performance of proposed PFD. From the experimental results, it has the better dead zone, duty cycle and response characteristics than conventional PFDs.

• Journal of the Korean Society of Clothing and Textiles
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• v.13 no.4
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• pp.319-329
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• 1989

The present paper mainly cocerns, in social aspect of the cultural change, with how cholik was introduced and accepted in $Kory\v{o}$ dynasty. It was through cultural transmission in political relations with Won dynasty that $ch\v{o}$ lik was first listed on our own costume system in later $Kory\v{o}$ dynasty. The acceptance by $Kory\v{o}$ society can be interpreted as the twofold effects; positively, it enriched our costume system and, negatively, it brought about various conflicts, which in turn caused some unwelcome reactions. Once it had permeated into $Kory\v{o}$ culture. it could not avoid being changed by social conditions. The changing process can be defined as the dual cycles of fashion. The first one startd at mid peroid of $Kory\v{o}$ when King $Chung-ry\v{o}$l provided a law to wear the $W\v{o}n$ costume and. ended at larter $Kory\v{o}$ of King Kong-min's reign. The second cycle rose in the period between King Sejong's reign and late $Chos\v{o}n$. Each of the two cycles appeared to have its own characteristics; 1. The first cycle. 1) In spite of the long period of a century, the cycle was very abrupt both in development and decline. 2) The abrupt pattern of the cycle can be attributed to the nation-wide law provided by the ruler. 2. The second cycle. 1) Compared with the first cycle, the curve was rather slow. 2) The fashion originated from the hyperimitation of the government officials, since the costume was the royal gift by Chinese Emperor. 3) The main cause of the development of the fastion was the wars, rather than the public preference. 4) The main cause of the decline of the fashion was that it could no more differentiate the social status, that the wearer was laughed at by the Chinese, and that the long period of wearing the same dress stimulated the fashion psychology. 5) The increasing size of the costume rather decreased the very function of the costume.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.14 no.4
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• pp.316-322
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• 2001

Cathode materials $LiMn_{2-y}$$M_{y}$ $O_4$(M=Zn and Mg) were obtained by reacting the mixture of LiOH.$H_2O$, Mn $O_2$ and MgO ar ZnO at 80$0^{\circ}C$ for 36h in an air atmosphere. These materials showed an extended cycle life in lithium-anode cells working at room temperatue in a 3.0 to 4.3V potential window. Among these materials, LiM $n_{1.9}$M $g_{0.1}$ $O_4$ showed the best cycle performance in terms of the capacity and cycle life. The discharge capacities of the cathode for the Li/LiM $n_{1.9}$ $M_{0.1}$ $O_4$ cell at the 1st cycle and at the 70th cycle were about 120 and 105mAh/g, respectively. This cell capacity is retained by 88% after 70th cycle. In cyclic voltammetry measurement, all cells revealed tow oxidation peaks and reduction peaks. However, Li/$LiMn_{2-y}$$M_{y}$ $O_4$ cell substituted with Zn and Mg showed new reaction peak during reduction reaction.eaction.ion.ion.

• Journal of the Chungcheong Mathematical Society
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• v.29 no.4
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• pp.573-584
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• 2016

Invertible transformations over n-bit words are essential ingredients in many cryptographic constructions. Such invertible transformations are usually represented as a composition of simpler operations such as linear functions, S-P networks, Feistel structures and T-functions. Among them T-functions are probably invertible transformations and are very useful in stream ciphers. In this paper we will characterize a secure trinomial on ${\mathbb{Z}}_{2^n}$ which generates an n-bit word sequence without consecutive elements of period $2^n$.

• Communications of the Korean Mathematical Society
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• v.32 no.4
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• pp.805-810
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• 2017

Let $C_n$ be the cycle graph of order n on the vertices $v_0,v_1,{\ldots},v_n$ and $C^k_n$ be the k-th power of $C_n$. In this article we determine the hull-number of $C^k_n$.

• Journal of applied mathematics & informatics
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• v.29 no.1_2
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• pp.247-255
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• 2011

Invertible functions with a single cycle property have many cryptographic applications. The main context in which we study them in this paper is pseudo random generation and stream ciphers. In some cryptographic applications we need a generator which generates binary sequences of period long enough. A common way to increase the size of the state and extend the period of a generator is to run in parallel and combine the outputs of several generators with different period. In this paper we will characterize a secure quadratic polynomial on $\mathbb{Z}_{2^n}$, which generates a binary sequence of period long enough and without consecutive elements.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.4
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• pp.158-164
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• 2003

The air circuit breaker (ACB) with the spring-actuated mechanism was studied to improve the fatigue-proof characteristics of its link. The low-cycle fatigue fracture phenomenon occurred on the critical link, called h-link, of ACB from the repeated rapid closing and opening operations. To analyze the cause of failure, dynamic FE-analysis on the b-link part of ACB was performed considering tile velocity and acceleration of the links per time as boundary conditions, which were obtained by using ADAMS. Also, the S-N curve obtained by experiments was used to investigate requirement on the fatigue-proof characteristics. Then, to reduce the maximum tensile stress on the h-link, three types of h-link were examined and one of them was selected.

• Magazine of the Korean Society of Agricultural Engineers
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• v.41 no.4
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• pp.92-103
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• 1999

Recently structural damage has been frequently observed in reinforced concrete brdiges due to repeated loads such as vehicular traffic an due to continual overloads by heavy duty trucks. Therefore, the purpose of this experimental stduy is to investigate the damage mechanism due to fatigue behavior of high-strength reinforced concrete beams under repeated loads. From the test results, the relation of cycle loading to deflection is on the mid-span , the crack growth and the modes of failure according to cycle number, fatigue life and S-N curve were observed through the fatigue test. Based on the fatigue test results , high-strength reinforced concrete beams failed to 57 ∼66 percent of the static ultimate strength . Fatigue strength aobut two million cycles from S-N curves was certified by 60 percent of static ultimate strength.