• Journal of the Korean Mathematical Society
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• v.54 no.2
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• pp.461-477
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• 2017

A dual substructuring method with a penalty term was introduced in the previous works by the authors, which is a variant of the FETI-DP method. The proposed method imposes the continuity not only by using Lagrange multipliers but also by adding a penalty term which consists of a positive penalty parameter ${\eta}$ and a measure of the jump across the interface. Due to the penalty term, the proposed iterative method has a better convergence property than the standard FETI-DP method in the sense that the condition number of the resulting dual problem is bounded by a constant independent of the subdomain size and the mesh size. In this paper, a further study for a dual iterative substructuring method with a penalty term is discussed in terms of its convergence analysis. We provide an improved estimate of the condition number which shows the relationship between the condition number and ${\eta}$ as well as a close spectral connection of the proposed method with the FETI-DP method. As a result, a choice of a moderately small penalty parameter is guaranteed.

• Archives of design research
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• v.12 no.3
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• pp.93-103
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• 1999

This study is investigated the formative characteristics of Rap Music and Hiphop fashion, and I try to comprehend about the fashion mind and fashion culture of teenager 1. Teenager's Hiphop Fashion is subcultures, the fashion culture of teenager reflects their unique identity. 2. The formative characters of Rap Music and Hiphop Fashion are the incompatibility ignored their body size and the popularity caused street fashion imitation, the unbalance ignored a principle of fashion design. 3. Hiphop Fashion is consist of jump-style jacket, hood -shirt, stripe T-shirt and drum pants, baggy pants, snowboard pants and so on. 4. The characters of Hiphop Fashion is the breaking of rule and the destruction. 5. They select something which they like, even though the price is high, so they is tendency to editing coordinate 6. Fashion business for teenager, it needs an ideal conversion not for 'company' but for 'individual' As this results, fashion culture of teenager came out to the surface of water, because of Hiphop Fashion.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.06a
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• pp.455-460
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• 2000

Impact occurs when the vibration amplitude of a mechanical component exceeds a given clearance size. Examples of these mechanical systems include impact dampers, gears, link mechanism, rotor rub, and so on. The vibration due to impact has strong non-linear characteristics, which cannot be predicted by usual linear analysis. The designs of mechanical systems with impacts should be done on the basis of overall dynamic characteristics of the systems. In this paper, the nonlinear behaviors of a beam with a periodically moving support and a rigid stop are investigated numerically and experimentally. The beam vibration with impact is modeled by the equations of motion containing piecewise linear restoring forces and by the coefficient of restitution, respectively. Experimental and numerical results show jump phenomena and higher-harmonic vibrations. The effects between the increase of stiffness during impact and the coefficient of restitution are investigated through the comparison of the experimental and numerical results.

• Journal of the Korean Statistical Society
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• v.32 no.4
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• pp.401-409
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• 2003

We consider a particle walking on the nonnegative integers and each unit of time it makes, given it is at site k, either a jump of size m distance units to the right with probability $p_{k}$ or it goes back (falls down) to its starting point 0, a retaining barrier, with probability $v_{k}\;=\;1\;-\;p_{k}$. This is a Markov chain on the integers $mZ^{+}$. We show that if $v_{k}$ has a nonzero limit, then the Markov chain is positive recurrent. However, if $v_{k}$ speeds to 0, then we may get transient Markov chain. A critical speeding rate to zero is identified to get transience, null recurrence, and positive recurrence. Another type of random walk on $Z^{+}$ is considered in which a particle moves m distance units to the right or 1 distance unit to left with probabilities $p_{k}\;and\;q_{k}\;=\;1\;-\;p_{k}$, respectively. A necessary condition to having a stationary distribution and positive recurrence is obtained.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.22 no.3
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• pp.137-154
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• 2018

We investigate the condensation transition of a zero range process with jump rate g given by $g(k)=\left\{\frac{M}{k^{\alpha}},\;if\;k{\leq}an\\{\frac{1}{k^{\alpha}}},\;if\;k>an,$ (0.1), where ${\alpha}$ > 0 and a(0 < a < 1/2) is a rational number. We show that for any ${\epsilon}$ > 0, there exists $M^*$ > 0 such that, for any 0<$M{\leq}M^*$, the maximum cluster size is between ($a-{\epsilon}$)n and ($a+{\epsilon}$)n for large n.

• Journal of the Korea Society of Computer and Information
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• v.17 no.10
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• pp.11-23
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• 2012

To achieve efficient code size reduction, this paper proposes a new compressed instruction set architecture for the OpenRISC architecture. The new instructions and their corresponding formats are designed by the profiling information of the existing instruction usage. New 16-bit instructions and 32-bit instructions are proposed to compressed the existing 32-bit instructions and instruction sequences, respectively. The proposed instructions can be classified into three types. The first is the new 16-bit instructions for the frequent normal 32-bit instructions such as add, load, store, branch, and jump instructions. The second type is the new 32-bit instructions for the consecutive two load instructions, two store instructions, and 32-bit data mov instructions. Finally, two new 32-bit instructions are proposed to compress function prolog and epilog code, respectively. OpenRISC hardware decoder is extended to support the new instructions. Experiments show that the efficiency of code size reduction improves by an average of 30.4% when compared to the OR1200 instruction set architecture without loss of execution performance.

• Journal of the Korean Ceramic Society
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• v.48 no.6
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• pp.525-530
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• 2011

We investigated the electrical properties the starting material and sintering condition on the laminated PTC thermistor for micro circuit protection. The influences of $BaTiO_3$ powder with the 0.3 and 0.45 ${\mu}m$ size and the electrical characteristics (Ba,Sr)$TiO_3$ sintered at 1350~1400$^{\circ}C$ for 2 h in a reducing atmosphere (1% $H_2/N_2$). The sintered (Ba,Sr)$TiO_3$ was increased pore and the grain size was decreased according to increasing Sr additions. In relative permittivity, the phase transition temperature of (Ba,Sr)$TiO_3$ was decreased for 2.5$^{\circ}C$ according to increasing 0.01 mole Sr additions, and the phase transition dose not appeared about 0.3 mole Sr addition. The (Ba,Sr)$TiO_3$ was show the low resistance from 0.01 mole to 0.05 mole by Sr addition, regardless of sintering temperature. The (Ba,Sr)$TiO_3$ was show $10^2$ jump order at 0.1 and 0.2 mole Sr addition, and PTCR of the sintered $(Ba_{0.7}Sr_{0.3})TiO_3$ does not appeared about 0.3 mole Sr addition, regardless of the sintering temperature and starting material size.

• Proceedings of the Korean Magnestics Society Conference
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• 2003.06a
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• pp.260-261
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• 2003

It is recognized that the magnetization reverses with a sequence of discrete and jerky jumps, known as the Barkhausen effect. Recently, interest in the Barkhausen effect has grown as it is a good example of dynamical critical behavior, evidenced by experimental observation of a power law distribution of the Barkhausen jump size. So far, most experimental studies have been carried out on bulk samples using a classical inductive technique, which is difficult to apply to thin film samples mainly due to the ]ow signal intensity. For this reason, very few experiments have been done on two-dimensional ferromagnetic thin films. In this talk, we report a direct domain observation of Barkhausen avalanche at criticality in Co and MnAs thin films investigated by means of a magnetooptical microscope magnetometer (MOMM), capable of time-resolved domain observation with an image grabbing rate of 30 frames/s in real time. In Fig. 1, we demonstrate a series of six representative domain-evolution patterns of 25-nm Co film observed successively by means of the MOMM, where one can directly witness Barkhausen avalanche.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.3
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• pp.217-221
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• 2008

In this study, We have been investigated the effect of calcination temperature and high-energy ball-milling of powder influences the $BaTiO_3$-based PTCR(Positive Temperature coefficient Resistance) characteristics and microstructure. The mixed powder was obtained from $BaCO_3$, $TiO_2$, $CeO_2$ ball-milled in attrition mill. The mixed powder was calcine from 1000 $^{\circ}C$ to 1200 $^{\circ}C$ in air and then it was sintered in reduction- re-oxidation atmosphere. As a result, The room-temperature electrical resistivity decreased and increased with increasing calcination temperature. specially, Attrition milled powder could have low room-temperature resistivity and high PTC jump order at 1100 $^{\circ}C$. attrition milling had lower room-temperature resistivity than ball milling. Particle size decreased by Attrition milling of powder influences in calcination temperature and room-temperature resistivity.

• Fashion & Textile Research Journal
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• v.8 no.6
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• pp.618-626
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• 2006

This research explored the actual conditions, problems and design preferences of dementia inpatient clothing. Data were collected by surveying 21 dementia hospitals and nursing care facilities and 87 caregivers and nurses of dementia hospitals. The collected data were analysed through frequency analysis, descriptive analysis and factor analysis. The results were as follows, First, the inpatient clothes of dementia hospitals were two-piece styles, the shirts of front opening with buttons and pants of no opening with elastic band. Those of dementia care facilities were two piece styles of shirts and pants, training suits or private plain clothes not uniform. Severe dementia inpatient dressed uniforms of the jump suits or two piece styles in some dementia care facilities. Second, the problems of dementia inpatient clothing were composed of suitability of raw and subsidiary clothing material, diversity of design and size, durability and form stability of clothes and elastic bands. Third, the design elements similar to those of existing inpatient clothing were preferred with regard to improving dementia inpatient clothing. That is, the design preferences of shirts showed front opening style with buttons, round neckline and a three-quarter-length sleeves. Those of pants came out no opening style with elastic band and full length. Also, pink color and natural patterns were preferred, and the private plain clothing of inpatient and fusion Han-bok style were somewhat preferred.