• Publications of The Korean Astronomical Society
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• v.22 no.3
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• pp.83-87
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• 2007

We designed the Intermediate Frequency(IF) distributor for multi beam backend system and manufactured Voltage to Frequency Converter(VFC) to measure the multi-beam receiver performance. Multi beam receiver has 15 channel receivers and can get 15 spectrums at once. The multi beam receiver has more observation efficiency than single beam receiver. We manufactured the 15 IF distributors to distribute IF signal for Autocorrelation spectrometer that is radio signal processor. Also, we manufactured the VF Converter to test the performance measurement of receiver for Korea VLBI Network(KVN) system which is under-construct in Seoul, Ulsan and Jeju. As a result of performance measurement, we could obtain linearity of 99.4% on the input power vs output frequency and measured the operating range of input frequency.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1993.06a
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• pp.802-805
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• 1993

A method of automatic learning of fuzzy if-then rules with certainty factors from the given input-output data is developed. A certainty factor expresses the degree to which a fuzzy if-then rule is fitting to the given data. Fuzzy if-then rules with certainty factors are generated without optimization techniques. The obtained fuzzy if-then rules can be regarded as an approximator of a non-linear function. This method is applied to GMDH (Group Method of Data Handling) to cope with difficulty in approximating multi-input functions with fuzzy if-then rules.

• Journal of the Korean Mathematical Society
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• v.50 no.5
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• pp.1083-1103
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• 2013

The concepts of reversible, right duo, and Armendariz rings are known to play important roles in ring theory and they are independent of one another. In this note we focus on a concept that can unify them, calling it a right Armendarizlike ring in the process. We first find a simple way to construct a right Armendarizlike ring but not Armendariz (reversible, or right duo). We show the difference between right Armendarizlike rings and strongly right McCoy rings by examining the structure of right annihilators. For a regular ring R, it is proved that R is right Armendarizlike if and only if R is strongly right McCoy if and only if R is Abelian (entailing that right Armendarizlike, Armendariz, reversible, right duo, and IFP properties are equivalent for regular rings). It is shown that a ring R is right Armendarizlike, if and only if so is the polynomial ring over R, if and only if so is the classical right quotient ring (if any). In the process necessary (counter)examples are found or constructed.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.1229-1232
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• 1996

This paper proposes the passive redundancy algorithm of multi-controller structure applicable to the steam generator level control system in the low power operating range. In the passive redundancy scheme of multi-controller structure, two suitable controllers exist if the plant is strongly stabilizable. One of the two controllers can be selected arbitrarily only if it is stable. In particular, this paper shows that the passive redundancy scheme can be efficiently used with PID and GPC control algorithms through simulation studies on the control of the steam generator.

• 한국데이터정보과학회:학술대회논문집
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• 2003.05a
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• pp.159-170
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• 2003

This Paper analyzed simultaneous activities of the time use survey by Korea National Statistical Office to use data mining‘s association rule. The survey of National Statistical Office in 1999 considered general analysis for simultaneous activities. But if we use the association rule, we can found the ratio of particular activities at the same time. And we found the probability that another activities practise if we act one particular activity. Using this association rule of data mining we can do more developed and analytical sociological study.

• 제어로봇시스템학회:학술대회논문집
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• 1991.10a
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• pp.476-481
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• 1991

This paper investigates the relationship between the two problems, supervisor reduction and observation function (projection) design, which arise in supervisory control of DEDS. It is shown through an example that a reduced supervisor of minimal size does not necessarily result in a maximal projection when a projection design method which uses the transition structure of a supervisor is applied. Also, if an L-realizable projection P is available and if a supervisor has a special structural feature, a cover C for supervisor reduction can be easily obtained. By investigating the control-compatibility of states of the reduced supervisor based on C, we can also check maximality of P in a simple manner.

• The Pure and Applied Mathematics
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• v.1 no.1
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• pp.7-11
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• 1994

Classically, valuation theory is closely related to the theory of divisors and conversely. If D is a Dedekined ring and K is its quotient field, then we can clearly construct the theory of divisors on D (or K), and then we can induce all the valuations on K ([3]). In particular, if K is a number field and A is the ring of algebraic integers, then since Z is Dedekind, A is a Dedekind rign and K is the field of fractions of A.(omitted)

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2004.11a
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• pp.111-116
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• 2004

This study is given that on the bridge construction in marine by GPS, specially, choice of station for footing construction of marine bridge. You can get positive datum in the checking of marine excavation, if you use together Total Station and GPS. In the result of comparision of upper surveying methods, Surveying datum is gotten error of less than 30mm(The depth of water 10～l5mm, station 7～10mm). This study show that hereafter if you use GPS in bridge construction in marine you can get accurateiy datum.

• Proceedings of the Korea Information Processing Society Conference
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• 2019.05a
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• pp.431-434
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• 2019

In the case of blur processing, it is common to use a tool such as Photoshop to perform processing manually. However, it can be considered very efficient if the blur is processed at one time in the object detection process. Based on this point, we can use the object detection model to blur the objects during the process. The object detection is performed by using the YOLO [3] model. If such blur processing is used, it may be additionally applied to streaming data of video or image.

• Bulletin of the Korean Mathematical Society
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• v.58 no.5
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• pp.1247-1260
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• 2021

We introduce the notion of barycentric transformation of Fano polytopes, from which we can assign a certain type to each Fano polytope. The type can be viewed as a measure of the extent to which the given Fano polytope is close to be Kähler-Einstein. In particular, we expect that every Kähler-Einstein Fano polytope is of type B_∞. We verify this expectation for some low dimensional cases. We emphasize that for a Fano polytope X of dimension 1, 3 or 5, X is Kähler-Einstein if and only if it is of type B_∞.