• 대한수학회지
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• 제57권3호
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• pp.793-807
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• 2020

Stable range of rings is a unifying concept for problems related to the substitution and cancellation of modules. The newly appeared element-wise setting for the simplest case of stable range one is tempting to study the lifting property modulo ideals. We study the lifting of elements having (idempotent) stable range one from a quotient of a ring R modulo a two-sided ideal I by providing several examples and investigating the relations with other lifting properties, including lifting idempotents, lifting units, and lifting of von Neumann regular elements. In the case where the ring R is a left or a right duo ring, we show that stable range one elements lift modulo every two-sided ideal if and only if R is a ring with stable range one. Under a mild assumption, we further prove that the lifting of elements having idempotent stable range one implies the lifting of von Neumann regular elements.

• 대한수학회지
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• 제44권4호
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• pp.903-913
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• 2007

A ring R has weakly stable range one provided that aR+bR=R implies that there exists a $y{\in}R$ such that $a+by{\in}R$ is right or left invertible. We prove, in this paper, that every regular element in an exchange ring having weakly stable range one is the sum of an idempotent and a weak unit. This generalize the corresponding result of one-sided unit-regular ring. Extensions of power comparability and power cancellation are also studied.

• 대한수학회논문집
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• 제32권2호
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• pp.267-276
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• 2017

In this paper we introduce rings that satisfy regular 1-stable range. These rings are left-right symmetric and are generalizations of unit 1-stable range. We investigate characterizations of these kind of rings and show that these rings are closed under matrix rings and Morita Context rings.

• 대한수학회보
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• 제47권3호
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• pp.653-661
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• 2010

Let R be a ring, and let $\Psi$(R) be the ideal generated by the set {x $\in$R | 1 + sxt $\in$ R is unit-regular for all s, t $\in$ R}. We show that $\Psi$(R) has "radical-like" property. It is proven that $\Psi$(R) has stable range one. Thus, diagonal reduction of matrices over such ideal is reduced.

• 한국정밀공학회지
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• 제21권2호
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• pp.203-209
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• 2004

Compliant bi-stable mechanism allows two stable states within its operation range staying at one of the local minimum states of the potential energy. Energy storage characteristics of the bi-stable mechanism offer two distinct and repeatable stable states, which require no power input to maintain it at each stable state. This paper suggests an equivalent model of the chevron-type bi-stable microactuator using the equivalent spring stiffness in the rectilinear and the rotational directions. From this model the range of spring stiffness where the bi-stable mechanism can be operated is analyzed and compared with the results of the FEA (Finite Element Analysis) using ANSYS for the buckling analysis, both of which show a good agreement. Based on the analysis, a newly designed chevron-type bi-stable MEMS actuator using hinges is suggested for the latch-up operation. It is found that the experimental response characteristics of around 36V for the bi-stable actuation for the 60$mu extrm{m}$ stroke correspond very well to the results of the equivalent model analysis after the change in cross-sectional area by the fabrication process is taken into account. Together with the resonance frequency experiment where 1760Hz is measured, it is shown that the chevron-type bi-stable MEMS actuator using hinges is applicable to the optical switch as an actuator.

• 한국실내디자인학회논문집
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• 제21권6호
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• pp.137-146
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• 2012

This study introduced the concept of Primacy Effect for the analysis of the observation characters by time so as to analyze the characters of information which the users observing the lobby in a public space get when they encounter the space. From the viewpoint that the first impression on any space can motivate the judgement of space and continuous activities, the time range with the observation characters which can be regarded as Primacy Effect was analyzed in the aspects of continuity and saccade. First, with the case of alignment by time on three times of continuous observation, the perception attributes of subjects were shown to be very different among one another depending on which time range was applied for alignment. Second, the subjects with low average value of continuous observation times were found to be relatively stable in "ii~iii time ranges" and the time range of "0~5.10 seconds" was known to be the time range of relatively stable analysis for the characters of subjects' primacy effect to be analyzed. Third, the change of the amount of acquired information could be examined concretely through the analysis of observation attributes by time range, and the time range of "iii time range" showed more stable changing characters than other time ranges. Fourth, in the "iii time range" set up as a proper time range for the analysis of primacy effect had higher average value of 3.9 times of observation frequency compared with 6 times of continuous observation. As a grand average, 6 times(19.3) of average observation value was between 3 times(21.3) and 9 times(16.9), which enabled to set up 6 times of continuous observation as the number of observation times for stable analysis of primacy effect.

• 한국정밀공학회지
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• 제19권7호
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• pp.125-132
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• 2002

This paper shows an experimental magnetic levitation table using one degree-of-freedom active control. The magnetic levitation table using repulsions of permanent magnets was theoretically presented already. Thus the objective of this paper is to prove stable levitation with only one degree-of-freedom active control experimentally. For the design of the system, at first, permanent magnets are selected. Secondly, the spring constants of the virtual spring are obtained by simulation. Thirdly, the moving magnets are arranged using a stable layout relation. Fourthly, a linear voice coil motor is designed. Finally, the magnetic levitation system is manufactured. The phenomenon of stable levitation in the manufactured table is proven by means of dynamic time and frequency responses. The differences between the theoretical natural frequencies and experimental ones are analyzed. Also, stable range in the control direction is shown experimentally.

• 약학회지
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• 제39권1호
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• pp.24-30
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• 1995

Lectin from mistletoe(Viscum coloratum) fermented by Lactobacillus plantarum was compared with the lectin from unfermented mistletoe. Agglunating activity of fermented mistletoe was stable at pH 3.77~8.71, at temperature range of $0~40^{\circ}C$ and in the presence of 9 mental ions, which results are similar to unfermented one, but less stable at pH 2.03~3.00 and more stable at temperature $60~80^{\circ}C$ than lectin from unfermented one. Agglunating activity of lectin from mistletoe fermented for 1 or 2 days and from fraction number 42~54 was not inhibited by all sugars used except for lectin from fraction number 21~34. Mitogenic activity to murine lymphpocytes of lectin from mistletoe was decreased by fermentation process.

• Journal of Microbiology
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• 제39권3호
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• pp.177-180
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• 2001

Glycinecin A, a bacteriocin produced by Xanthomonas campestris pv. glycines, inhibits the growth of X. c. pv. vesicatoria. We have reported that purified glycinecin A is composed of two polypeptides, is active over a wide range of pH (6 to 9), and is stable at temperatures up to 60$\^{C}$. Glycinecin A is a heterodimer consisting of 39- and 14-kDa subunits; the two encoding genes, glyA and glyB, respectively, have been cloned (Heu et al. 2001. Appl. Environ. Microbiol. 67, 4105-4110). Co-expression of glyA and glyB in the same cell is essential for bacteriocin activity. We constructed and produced a chimeric glycinecin A connecting glyA and glyB in one open reading frame. The chimeric glycinecin A has the same bactericidal activity as the wild-type glycinecin A. However, the chimeric glycinecin A is more stable in a wider range of pH and temperature.

• 한국광학회지
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• 제16권6호
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• pp.527-534
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• 2005

하나의 DFB 영역, 위상 조정 영역과 이득 영역으로 구성된 다중 전극 DFB 레이저의 pulsation 동작 특성을 살펴본다. Anti-phase (AP) complex-coupled (CC) DFB 구조를 사용한 경우가 in-phase CC DFB 구조나 index-coupled DFB 구조를 사용한 경우에 비하여 안정된 pulsation 동작이 발생하는 이득 영역과 위상 조정 영역의 전류 범위가 큼을 알 수 있다. AP CC DFB 구조를 사용한 경우 결합 세기가 커질수록, 이득 결합 계수가 커질수록 안정된 pulsation 동작이 발생하는 이득 영역의 전류 범위가 증가하고 pulsation 주파수의 튜닝 영역이 커짐을 볼 수 있다. 또한 위상 조정 영역의 위상 변화에 의한 pulsation주파수의 튜닝 영역도 커짐을 볼 수 있다. 고정된 결합 세기에서 DFB 영역의 길이가 증가할수록 pulsation 동작이 발생하는 위상 조정 영역과 이득 영역의 전류 범위가 증가하여 pulsation 주파수 튜닝 영역이 넓어짐을 볼 수 있다.