• Communications of the Korean Mathematical Society
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• v.23 no.4
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• pp.479-485
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• 2008

In this note, we study arithmetic properties for the exponents of modular forms on ${\Gamma}_0(p)$ for primes p. Our aim is to refine the result of [4] by using the geometric property of the modular curve of ${\Gamma}_0(p)$.

• Communications for Statistical Applications and Methods
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• v.21 no.3
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• pp.201-212
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• 2014

We provide a simple basic method to find bounds for higher order moments of unimodal distributions in terms of lower order moments when the random variable takes value in a given finite real interval. The bounds for moments in terms of the geometric mean of the distribution are also derived. Both continuous and discrete cases are considered. The bounds for the ratio and difference of moments are obtained. The special cases provide refinements of several well-known inequalities, such as Kantorovich inequality and Krasnosel'skii and Krein inequality.

• 제어로봇시스템학회:학술대회논문집
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• 1993.10a
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• pp.1213-1218
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• 1993

Variable structure control is applied to the robust output tracking control problem of general nonlinear multi-input multi-output (MIMO) systems. Using the concept of relative degree and minimum phase, input/output(I/O) linearization is undertaken. For I/O the linearized system, a new sliding hyperplanes design method is proposed. In this procedure, we can construct very robust and efficient sliding mode controller for general nonlinear systems of relative degree higher than two. The control results are illustrated by adopting a numerical example.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.643-646
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• 1997

Gear trains are used in many machinery for variable speed ratios. Typical shapes of gear trains are tivo categories : simple gear trains and planetary gear trains. This paper presents the kinematic ctraracteristics for planetary gear trains. The characteristics are the constraints of geometric relationships, number of gears, speed of each gear. and speed ratio of the train. The objective goal of this paper provides the CAI) software, which is the academic tool for understanding the kinematics of the planetary gear trains.

• Journal of the Chungcheong Mathematical Society
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• v.22 no.1
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• pp.7-10
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• 2009

With the introduction of a new parameter $n{\geq}1$, Kim generalized an upper bound for the exponential function that implies the inequality between the arithmetic and geometric means. By a change of variable, this generalization is equivalent to exp $(\frac{n(x-1)}{n+x-1})\;\leq\;\frac{n-1+x^n}{n}$ for real ${n}\;{\geq}\;1$ and x > 0. In this paper, we show that this inequality is true for real x > 1 - n provided that n is an even integer.

• Proceedings of the KSRS Conference
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• 2002.10a
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• pp.216-221
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• 2002

A spherical Earth surface is used fur realistic analysis of the geometrical performance characteristics about the variation of satellite altitude and 2-dimensional line-of-sight(LOS) tilt angle in a satellite imager using Time Delay and Integration(TDI) technique with fixed integration time. In the spherical Earth surface model TDI synchronization using LOS tilt is investigated as a solution to compensate geometric performance degradation due to altitude decrease. This result can be used fur a TDI CCD imager with variable integration time in a certain as well.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.6
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• pp.355-364
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• 2018

The objective of this study is to conduct basic research for the development of programs for improving university students' communication competence. As such, it seeks to determine if positive psychological capital can mediate the relationship between the geometric psychology type and communication competence. To that end, 321 Korean university students were surveyed using a questionnaire, and the data underwent scale reliability analysis, regression analysis, and path analysis. Regression analysis revealed the consistent regression results of variables, including geometric psychology type, positive psychological capital, and communication competence. Path analysis confirmed that positive psychological capital mediated the relationship between the geometric psychology type and communication competence, and the results suggested different patterns according to type of geometric psychology. The circle type mediated the sub-variable resilience vis-a-vis communication competence, and directly influenced the latter. The triangle type mediated the sub-factors of positive psychological capital - self-efficacy and resilience -vis-a-vis communication competence, and thus influencing the latter. The square type mediated the sub-factor of positive psychological capital - self-efficacy - vis-a-vis communication competence, and directly influenced the latter. The S type did not mediate positive psychological capital vis-a-vis communication competence, but directly influenced the latter. Thus, considering the above findings, in order to develop university students communication improvement programs, programs should be developed with the application of positive psychological capital considering geometric psychology type.

• Journal of Power System Engineering
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• v.2 no.2
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• pp.73-80
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• 1998

The identification of drilling joint dynamics which consists of drilling and structural dynamics and the on-line time series detection of malfunction process is substantial not only for the investigation of the static and dynamic characteristics but also for the analytic realization of diagnostic and control systems in drilling. Therefore, We have discussed on the comparative assessment of two recursive time series modeling algorithms that can represent the drilling operation and detect the abnormal geometric behaviors in precision roundshape machining such as turning, drilling and boring in precision diemaking. For this purpose, simulation and experimental work were performed to show the malfunctional behaviors for drilling operation. For this purpose, a new two recursive approach (Recursive Extended Instrument Variable Method : REIVM, Recursive Least Square Method : RLSM) may be adopted for the on-line system identification and monitoring of a malfunction behavior of drilling process, such as chipping, wear, chatter and hole lobe waviness.

• Proceedings of the KSME Conference
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• 2000.04a
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• pp.315-320
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• 2000

The optimal design for the shape of metal ring obturator under the high pressure using parameter study on the stress analysis considering effects of design variable is presented and is compared to experimental results. The design variables are such as thickness, taper, radius of shape of the obturation ring. For optimization of the obturation ring, the weight is maximized subject to maximum stress of the obturator within allowable stress. The design constraints are geometric elements of design variables. The trends of parametric study are in good agreement with the experimental results.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1994.10a
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• pp.504-509
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• 1994

Recently SMT is used widely to place the SMD on bare board which is very small and highly integrated. And that is one of the issue directly in the electric products assembly process and especiallly in the field of optimizing electric product's performance, automatically tuning method which is highly demanded in the electronics industry. To tune product's performance, variable resistances's resistivity should be changed until it has good performance characteristics. In this paper to automatically regulate the 8mm camcoder's performance, it is proposed variable resistence's center position and orientation detection algorithm by image processing, which has very precise and accurate result. And we found optimal conditions which can have effects on image acquisition process. And real time processing is done by DSP to detect vr's center and orientation. This results make it possible to utilize proposed image processing algorithm and system directly in electronics industry.