• 대한수학회논문집
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• 제35권4호
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• pp.1057-1073
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• 2020

In this paper, we study some of the factorization aspects of rational multicyclic monoids, that is, additive submonoids of the nonnegative rational numbers generated by multiple geometric sequences. In particular, we provide a complete description of the rational multicyclic monoids M that are hereditarily atomic (i.e., every submonoid of M is atomic). Additionally, we show that the sets of lengths of certain rational multicyclic monoids are finite unions of multidimensional arithmetic progressions, while their unions satisfy the Structure Theorem for Unions of Sets of Lengths. Finally, we realize arithmetic progressions as the sets of distances of some additive submonoids of the nonnegative rational numbers.

• Journal of the Optical Society of Korea
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• 제19권2호
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• pp.165-168
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• 2015

A simple method to determine the focal length of a lens using the Talbot image is presented. This method uses only one grating, requiring neither Moir$\acute{e}$ fringe analysis nor the angle between the gratings. The original Fourier transform was used to access the spectrum beyond the limitation set of the usual fast Fourier transform to determine the (de)magnification accurately enough to be used for the focal length. A set of Talbot images simulated numerically with the Fresnel diffraction integral was used to demonstrate the method. For focal lengths between 5550 mm and 5650 mm, the mean difference between the focal lengths determined from the Talbot images and the true values was 3.3 mm with the standard deviation of the difference being 3.8 mm. The true focal lengths can be recovered with an accuracy of 0.06%.

• 대한기계학회논문집A
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• 제30권10호
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• pp.1293-1297
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• 2006

In this paper, kinematic analysis of a double-action link-type die set for enclosed die forging is carried out. The structure of the die set and its operational principle during enclosed die forging are introduced in detail. A closed-form solution of the relative velocity of the middle plate with respect to the upper plate after the upper and lower dies are enclosed is given in terms of the link lengths and the distance from the lower pin to the upper pin of the link system. The effect of the link lengths on both strokes and velocities is investigated. It has been shown that the relative velocity of the middle plate with respect to the upper plate varies almost linearly with the stroke of the upper plate.

• 한국의류학회지
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• 제28권9_10호
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• pp.1320-1328
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• 2004

Purposes of the study were to find out the joint effects of two salient appearance cues-hair colors and hair lengths on males fashion images, using 729 university students in Daejon city and a Chungnam province. The study was a quasi experiment; the dependent variables were hair lengths(4 levels) and hair colors(4 levels)and the dependent variable was a set of semantic different of scales which was consisted of 40 hi-polar adjectives, The data were analyzed by a factor analysis, 3-way ANOVA, and the results were as follows. Hair lengths effected on the image of five dimensions, salient, social, potency, evaluate and dynamics while hair colors effected on salients, social and potency dimensions. The most significant interaction effect between hair color and lengths were existed on the salient image: For the longer haired males, the color effects became less evident then normal to shorten haired males and it can be concluded that when two salient cues were combined one cue's effect became discounted.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2000년도 추계학술대회논문집
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• pp.384-388
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• 2000

One-port acoustic characteristics of an in-duct source can be measured by the multi-load method using an overdetermined set of open pipes with different lengths as applied loads. The input data. viz. load pressure and load impedance, are usually contaminated by measurement error in the actual measurements, which result in errors in the calculated source parameters. In this paper, the effects of the errors in the input data on the results have been studied numerically, varying the number of loads and their impedances in order to determine what combination of the loads will yield the best result. An error analysis is applied to each case of possible loads, which consist of open pipes. It is noted that, frequently, only a set of open pipes is used when applying the multi-load method to the intake or exhaust sides of internal combustion engines. A set of pipe lengths which cause the calculated results to be least sensitive to the input data error can be found when using open pipe loads. The present work is intended to produce guidelines for preparing an appropriate load set in order to obtain accurate source properties of fluid machines.

• 대한수학회지
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• 제56권4호
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• pp.869-915
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• 2019

Let H be a Krull monoid with class group G such that every class contains a prime divisor. Then every nonunit $a{\in}H$ can be written as a finite product of irreducible elements. If $a=u_1{\cdot}\;{\ldots}\;{\cdot}u_k$ with irreducibles $u_1,{\ldots},u_k{\in}H$, then k is called the length of the factorization and the set L(a) of all possible k is the set of lengths of a. It is well-known that the system ${\mathcal{L}}(H)=\{{\mathcal{L}}(a){\mid}a{\in}H\}$ depends only on the class group G. We study the inverse question asking whether the system ${\mathcal{L}}(H)$ is characteristic for the class group. Let H' be a further Krull monoid with class group G' such that every class contains a prime divisor and suppose that ${\mathcal{L}}(H)={\mathcal{L}}(H^{\prime})$. We show that, if one of the groups G and G' is finite and has rank at most two, then G and G' are isomorphic (apart from two well-known exceptions).

• Bulletin of the Korean Chemical Society
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• 제12권2호
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• pp.211-213
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• 1991

The ground state of the oxygen molecule is calculated by various methods of coupled cluster approaches and many body perturbation theory using a double zeta plus polarization basis set and the UHF reference state. All the methods employed are capable of describing the oxygen molecule near the equilibrium bond length and the separated atom, but do not correctly depict the breaking of the multiple bond. For this basis set, including more correlations does not necessarily improve the agreement with experiment for molecular properties such as bond lengths and dissociation energies.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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• pp.1613-1616
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• 1997

In order to develop a human hand mechanism, a 5-bar finger with redundant actuation is designed and implemented. an optimal set of acutator locations and link lengths for the case of one redundant actuator is obtained by employing a composite design index which simulataneously consider several performance indices such as workspace, isotropic index, and force transmission ratio. Each joing is driven by an compact actuator mechanism having ultrasonic motor and a gear set with poeneiometer an controlled by VME Bus-based control system.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2006년도 춘계학술대회 논문집
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• pp.386-390
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• 2006

In this paper, kinematic analysis of a double-action link-type die set for the enclosed die forging is carried out. Operational principle of the die set in the enclosed die forging is introduced in detail. A closed form solution of the relative velocity of the middle plate with respect to the upper plate is given. The effect of link lengths on both strokes and velocities is investigated.

• 복식
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• 제57권5호
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• pp.151-165
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• 2007

Appearance matters in society today. Women want to feel good and look their best. They do make-up, wear garment and accessory for their good looking. Doing make-up, we have to know how we are look and to consider face shape. But it is difficult to recognize face shape. Because there is no standard face shape of adult women of quantitative analysis. The purpose of this study was to offer standard face shape of adult women in Korea. Furthermore, the study was to determine and differentiate face shape of each age group to set the basic data for the Korean beauty industry. In this study, photographs of 600 Korean women, age between $20{\sim}50's$, were indirectly measured in Venus face2D program. The measurements were analyzed by statistical methods. As a result of basic statistical data analysis, the average lengths of face were 196mm, lengths of forehead-hairline between eyebrows were 62mm, lengths of eyebrow between noses were 68mm, length of nose between chin were 66mm, and width of face were 150mm. By comparing to each age group's face using ANOVA, the statistically noticeable differences were found in measurements.