• Journal of Korean Port Research
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• v.12 no.1
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• pp.113-118
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• 1998

The Container crane is mainly used in the harbor. But in spite of this wide use, it is a fact that there are still areas for automation, concerning the operator and the control system. If the encoding function is enhanced, then control effect can be increased to some extent. Since the distance from the hoist to the trolley cam be measured, the moving distance from the loading and unloading can be minimized. If this is applied to the real system, hazard elements can be eliminated and in given time since more unloading can be done, congestion can be reduced.

• Bulletin of the Korean Mathematical Society
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• v.46 no.1
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• pp.135-146
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• 2009

In the present note we study the properties of weak Armendariz rings, and the connections among weak Armendariz rings, Armendariz rings, reduced rings and IFP rings. We prove that a right Ore ring R is weak Armendariz if and only if so is Q, where Q is the classical right quotient ring of R. With the help of this result we can show that a semiprime right Goldie ring R is weak Armendariz if and only if R is Armendariz if and only if R is reduced if and only if R is IFP if and only if Q is a finite direct product of division rings, obtaining a simpler proof of Lee and Wong's result. In the process we construct a semiprime ring extension that is infinite dimensional, from given any semi prime ring. We next find more examples of weak Armendariz rings.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.22 no.5
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• pp.501-509
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• 2011

Software defined radio(SDR) has a goal that places the analog-to-digital converter(ADC) as near the antenna as possible. But current technique actually can't do analog-to-digital converting about RF band signals. So one method is studying that samples RF band signals to IF band. One of the ways Sub-Sampling technique can convert signals from RF band to IF band without oscillator. If Sub-Sampling technique is used, over 2 bands can convert signals from RF band to IF band. But due to the filter performance in RF band, it is possible to generate interference between signals that is converted in low frequency band. The effect degrades performance. In this paper, we propose one method that uses time division multiplexing(TDM) method as a solution to avoid interference between signals. By doing TDM and Sub-Sampling at the same time that method can get signals without large changes of structures.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.39 no.4
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• pp.333-340
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• 1990

분산 송전송실정보에 의한 전력시스템의 경제운용=The transmission loss information produced in a line may be shared by both end buses connected to the line. Then, the loss may be seen as if it is discretely produced at both buses. Likewise, all transmission losses can be considered as if they are discretely produced at every bus distributed. The bus transmission loss equation can be defined, in which the loss information about connected lines are contained. This formulation can greatly enhance the computational efficiency for the economic control of both real powers and voltages. It requires solutions of two linear matrix equations, one for the calculation of incremental transmission losses and the other for the determination of voltage levels to be controlled. The Proposed approach is demonstrated through three sample systems and it is found that the solutions can be obtained after three iterations regardless of system sizes. This implies that only one-step search would be required for the solution if real informations would be available. Results are compared with those of optimal power flows.

• Journal of Astronomy and Space Sciences
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• v.35 no.4
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• pp.287-293
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• 2018

This paper presents a satellite relative navigation strategy for formation flying, which chooses an appropriate navigation algorithm according to the operating environment. Not only global positioning system (GPS) measurements, but laser measurements can also be utilized to determine the relative positions of satellites. Laser data is used solely or together with GPS measurements. Numerical simulations were conducted to compare the relative navigation algorithm using only laser data and laser data combined with GPS data. If an accurate direction of laser pointing is estimated, the relative position of satellites can be determined using only laser measurements. If not, the combined algorithm has better performance, and is irrelevant to the precision of the relative angle data between two satellites in spherical coordinates. Within 10 km relative distance between satellites, relative navigation using double difference GPS data makes more precise relative position estimation results. If the simulation results are applied to the relative navigation strategy, the proper algorithm can be chosen, and the relative position of satellites can be estimated precisely in changing mission environments.

• Journal of the Korean Institute of Intelligent Systems
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• v.18 no.5
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• pp.700-705
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• 2008

In this paper, a model to evaluate the sustainability management for small and middle enterprises was suggested. Also, the if-then rules and its decision tree for pattern analysis which is obtained by fuzzy ID3 from the data of sustainability management were shown. The suggested model can be used for the evaluation tool of competition increasement of enterprises. If the enterprise can recognize that the evaluation rule can be taken advantage of the sustainability management pattern analysis using fuzzy ID3, it is expected that they can use the rule effectively for self evaluation.

• Communications for Statistical Applications and Methods
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• v.4 no.1
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• pp.229-241
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• 1997

We consider discrimination curve and minimum dwell time for Poisson distribution and Poisson-power function distribution. Let the random variable X has Poisson distribution with mean .lambda.. For the hypothesis testing H$\_$0/:.lambda. = t vs. H$\_$1/:.lambda. = d (d$\_$0/ if X.leq.c. Since a critical value c can not be determined to satisfy both types of errors .alpha. and .beta., we considered discrimination curve that gives the maximum d such that it can be discriminated from t for a given .alpha. and .beta.. We also considered an algorithm to compute the minimum dwell time which is needed to discriminate at the given .alpha. and .beta. for the Poisson counts and proved its convergence property. For the Poisson-power function distribution, we reject H$\_$0/ if X.leq..'{c}.. Since a critical value .'{c}. can not be determined to satisfy both .alpha. and .beta., similar to the Poisson case we considered discrimination curve and computation algorithm to find the minimum dwell time for the Poisson-power function distribution. We prosent this algorithm and an example of computation. It is found that the minimum dwell time algorithm fails for the Poisson-power function distribution if the aiming error variance .sigma.$\^$2/$\_$2/ is too large relative to the variance .sigma.$\^$2/$\_$1/ of the Gaussian distribution of intensity. In other words, if .ell. is too small, we can not find the minimum dwell time for a given .alpha. and .beta..

• CELLMED
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• v.12 no.4
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• pp.17.1-17.1
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• 2022

PoongLyuYak exists everywhere. If you read the poem and get inspired, it becomes poem Yak (詩藥, poem medicine). If you look at the picture and fall it, it becomes picture Yak. When you feel refreshed by travelling, it becomes travel Yak. Music, dance, movie, nature, etc. are very nice examples. Even a leisurely life of driving, eating out, and drinking coffee is good PoongLyuYak for the body. Whether you're alone or in a group, if you can enjoy it, it's good medicine. According to the logic of the windy and flowing world, anything that can transform one's emotions, whether happy, sad, or trivial, can be a PoongLyuYak. This PoongLyuYak may be more effective than oral medications, inhalants, ointments, or injections. Rather than simply watching, listening, or imitating others, the effect is enormous when participating directly and performing and creative activities. The pleasure of seeing Heung-min Son playing soccer is also a PoongLyuYak, but it can be more enjoyable and the medicinal effect is much greater if you enjoy soccer yourself. Here are some examples of PoongLyu medicines the authors took with the joy of creation.

• Journal of the Korean Mathematical Society
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• v.51 no.6
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• pp.1305-1319
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• 2014

A submodule N of a right R-module M is called coneat if for every simple right R-module S, any homomorphism $N{\rightarrow}S$ can be extended to a homomorphism $M{\rightarrow}S$. M is called coneat-flat if the kernel of any epimorphism $Y{\rightarrow}M{\rightarrow}0$ is coneat in Y. It is proven that (1) coneat submodules of any right R-module are coclosed if and only if R is right K-ring; (2) every right R-module is coneat-flat if and only if R is right V -ring; (3) coneat submodules of right injective modules are exactly the modules which have no maximal submodules if and only if R is right small ring. If R is commutative, then a module M is coneat-flat if and only if $M^+$ is m-injective. Every maximal left ideal of R is finitely generated if and only if every absolutely pure left R-module is m-injective. A commutative ring R is perfect if and only if every coneat-flat module is projective. We also study the rings over which coneat-flat and flat modules coincide.

• Journal of Research and Publication Ethics
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• v.1 no.1
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• pp.23-28
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• 2020

Purpose: Focusing on Supreme Court precedents, we intend to establish criteria for judging research misconduct. Research design, data and methodology: In addition, I would like to propose the criteria for judging research misconduct by the KODISA, which applies the court's standards well in practice, and guidelines for preventing research misconduct. Research design, data and methodology: After classifying the case of research misconduct into six cases, the court's judgment and practical application will be reviewed. Results: First, research misconduct that has passed the disciplinary prescription can be punished. This is because the state of illegality continues to this day. Second, even if there were no punishment regulations at the time of research misconduct, it can be retroactively punished with the current punishment regulations. This is because research ethics is a universal and common standard and does not change. Third, if there is a fact that infringes on intellectual property rights, it is presumed unwritten intentions. Therefore, the act of taking and using the work of another person without permission or proper citation procedure, even if it is unintentional and for the public interest, is a research misconduct. Fourth, if there is an inappropriate citation notation, the intention of research misconduct is presumed. It is the judgment of the court that even if a quotation is marked, if it is incomplete, it is recognized as plagiarism. Fifth, if the author uses the work of another person without proper source indication, it is plagiarism even if the other person who owns the copyright agrees to it. The understanding or consent of some parties does not justify research misconduct in violation of public trust. Sixth, it is a research misconduct to create a new work without citations for one's previous work. In addition, even if there is a citation, if the subsequent writing is not original, it is a research misconduct. Conclusions: Academia should clarify the scope of research misconduct by referring to the Research Ethics Regulations of KODISA, and deal with research results that lack the value as creative works similar to those of research misconduct.