• Journal of the Korean Mathematical Society
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• v.50 no.6
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• pp.1271-1290
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• 2013

Let M be a fixed left R-module. For a left R-module X, we introduce the notion of M-prime (resp. M-semiprime) submodule of X such that in the case M=R, it coincides with prime (resp. semiprime) submodule of X. Other concepts encountered in the general theory are M-$m$-system sets, M-$n$-system sets, M-prime radical and M-Baer's lower nilradical of modules. Relationships between these concepts and basic properties are established. In particular, we identify certain submodules of M, called "primeM-ideals", that play a role analogous to that of prime (two-sided) ideals in the ring R. Using this definition, we show that if M satisfies condition H (defined later) and $Hom_R(M,X){\neq}0$ for all modules X in the category ${\sigma}[M]$, then there is a one-to-one correspondence between isomorphism classes of indecomposable M-injective modules in ${\sigma}[M]$ and prime M-ideals of M. Also, we investigate the prime M-ideals, M-prime submodules and M-prime radical of Artinian modules.

• Convergence Security Journal
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• v.11 no.3
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• pp.11-17
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• 2011

The acquisition of weapons systems test and evaluation in the early stages of the acquisition process as a source of data used for modeling and simulation are being actively encouraged. Thus, in the reliability of weapon systems acquisition can be called the most important part, and M&S to apply for this test reliability and accuracy of the assessment can provide, test time and cost savings, the pre-and post-test predictions and available data can provide. In this study, theoretical study of M&S to acquire weapon systems used for the importance of M&S, acquired the characteristics of the model, utilization for weapon systems acquisition, and weapon systems acquisition review for an effective utilization of M&S tries to find out.

• Journal of the Earthquake Engineering Society of Korea
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• v.10 no.2 s.48
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• pp.51-62
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• 2006

In the companion paper (I-Problem Statements of the Current Seismic Design Code), the current Korean seismic design code is required to be modified considering site characteristics in Korea for the reliable estimation of site amplification. In this paper, three site classification methods based on the mean shear wave velocity of the top 30m $V_{S30}$, fundamental site periods $(T_G)$ and bedrock depth were investigated and compared with each other to determine the best classification system. Not enough of a difference in the standard deviation of site coefficients $(F_a\;and\;F_v)$ to determine the best system, and neither is the difference between the average spectral accelerations and the design response spectrum of each system. However, the amplification range of RRS values based on $T_G$ were definitely concentrated on a narrow band than other classification system. It means that sites which have a similar behavior during earthquake will be classified as the same site category at the site classification system based on $T_G$. The regression curves between site coefficients and $T_G$ described the effect of soil non linearity well as the rock shaking intensity increases than the current method based on $V_{S30}$. Furthermore, it is unambiguous to determine sue category based on $T_G$ when the site investigation is performed to shallower depth less than 30m, whereas the current $V_{S30}$ is usually calculated fallaciously by extrapolating the $V_s$ of bedrock to 30m. From the results of this study, new site classification system based on $T_G$ was recommended for legions of shallow bedrock depth in Korea.

• Proceedings of the KIEE Conference
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• 1988.07a
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• pp.510-513
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• 1988

This paper describes an effective trunk loop signal processing method and analyzes execution time of program in the DTCP(Digital Trunk Circuit Processor) in the TDX-1A digital switching system. To predict a maximum trunk capacity, also analyzes to Z80A system clock(4Mbit/s, 2.5Mbit/s) and scanning period(8mS,5mS) respectively.

• Proceedings of the Korean Statistical Society Conference
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• 2002.05a
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• pp.61-66
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• 2002

We consider a generalized N-policy for an M/M/1 queueing system. The idle server starts to work with ordinary service rate when a customer arrives. If the number of customers in the system reaches N, the service rate gets faster and continues until the system becomes empty. Otherwise, the server finishes the busy period with ordinary service rate. We obtain the limiting distribution of the number of customers in the system. After assigning various operating costs to the system, we show that there exists a unique fast service rate minimizing the long-run average cost per unit time.

• The Journal of the Acoustical Society of Korea
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• v.22 no.4E
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• pp.176-182
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• 2003

As the needs for wireless Internet service is increasing, the needs for secure m-commerce is also increasing. Conventional security techniques are reinforced by biometric security technique. This paper utilized the voice as biometric security techniques. We developed speaker verification system for m-commerce (mobile commerce) via wireless internet and wireless application protocol (WAP). We named this system the mVprotek. We implemented the system as client-server architecture. The clients are mobile phone simulator and personal digital assistant (PDA). The verification results are obtained by integrating the mVprotek system with SK Telecom's code dimension multiple access (CDMA) system. Utilizing f-ratio weighting and virtual cohort model normalization showed much better performance than conventional background model normalization technique.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.4
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• pp.42-48
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• 2021

Recently, the defense industry has been improving high technology by developing convergence technology through the 4th industrial revolution. On the other hand, it is very difficult to guarantee the performance of high-tech weapon systems because the test for weapon systems has many risks and cannot perform in an actual operating environment. Therefore, M&S resources are needed to make sound weapon systems, but many people demand reliable M&S resources. Owing to the continuous demand and execution of the VV&A work, related rules have developed significantly, but tools and techniques for performing the work have not been developed. Hence, there are inefficient parts in the performance of work due to the absence of a systematic system. Accordingly, many risks may cause various safety accidents, such as security. This paper suggests a direction for the development of VV&A work procedures by improving efficiency and reducing risk.

• Proceedings of the KIEE Conference
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• 2006.10c
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• pp.491-493
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• 2006

We introduce Location PDA Program which is a mobile system to display current location on PDA. The current location is calculated based on collecting location through each fixed node. Each fixed node sends location information of mobile node to Cell Manager system. And then, Cell Manager calculates final location based on related information and sends it to every mobile system which is connected to server and displays current location.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1996.10a
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• pp.167-172
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• 1996

A Dual Mass Flywheel system is a evolution to the reduction of torsional vibration and impact noise occuring in powertrain when a vehicle is eit-her moving or idling. The name already explains what it is : The mass of the conventional single mass flywheel is divided. One section continues to belong to the mass moment of inertia of the engine-side. The ot-her section increass the mass moment of inertia of the transmission-side. The two masses are connected via a spring /damping system. This reduces the speed at which the dreaded resonance occurs to below idle speed. Since 1984 Dual Mass Flywheel has been de-veloped again and again. But the prosidures of de-velopment of D.M.F system didn't have had differe-nce from conventional clutch system's trial and err-or This paper presents the method for systematical design of D.M.F system with demensionless design variables of D.M.F system mass ratio between two flywheels λ. natual frequency rate of two flywheel s, ${\gamma}$and viscosity coefficient ζ. And experimental re-sults are used to prove these theoretical results.

• Proceedings of the Korea Information Processing Society Conference
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• 2022.11a
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• pp.758-760
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• 2022

본 연구는 머신러닝의 한 종류인 YOLOv5를 이용하여 기존 육안 선별작업을 자동화 하는 기계를 설계하는 것이다. 본 연구에서는 영상촬영과 선별작업을 진행하는 컨베이어 기구와 선별 프로그램을 제작하고, 모든 표면을 검사해 사과의 품질을 3단계로 구별하는 작업을 진행하였다. 결과적으로 투입된 사과의 품질을 성공적으로 분류 하였다.