• Journal of the Institute of Electronics Engineers of Korea TC
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• v.37 no.1
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• pp.12-22
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• 2000

This paper presents the window-based permit distribution scheme for efficient medium access control to support multiclass traffic in APON(ATM over passive optical network). The proposed MAC protocol considers the characteristics of QoS(Quality of Service) for various traffic classes. A periodic RAU(request access unit) in upstream direction, includes dedicative request fields for each traffic category within the request slot. The transmission of upstream cell is permitted by the proposed window-based spacing scheme which distributes the requested traffic into several segments in the unit of one spacing window. The delay sensitive traffic source such as CBR or VBR with the stringent requirements on CDV and delay, is allocated prior to any other class. In order to reduce the CDV, so that the permit arrival rate close to the cell arrival rate, Running-Window algorithm is applied to permit distribution processing for these classes. The ABR traffic, which has not-strict CDV or delay criteria, is allocated flexibly to the residual bandwidth in FIFO manner. UBR traffic is allocated with the lowest priority for the remaining capacity. The performance of proposed protocol is evaluated in terms of transfer delay and 1-point CDV according to various offered load. The simulation results show that our protocol has the prominent improvement on CDV and delay performance with compared to the previous protocol.

• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.313-316
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• 1998

Inspired by the principle of the open market, a future network service model is forced to permit a much greater degree of flexibility, reconfigurability, programmability, protability and maintainability in telecommunication infrastructure. In this paper, one of standardization activities for the open programmable network model, IEEE standardization project P1520 (Application Programming Interfaces for Networks), is discussed.

• Cement Symposium
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• no.1
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• pp.56-63
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• 1973

In cement industry in which three or more raw materials are used, the proportioning of raw materials is an essential step. When the materials are proportioned, each should be as nearly homogeneous chemically and physically as conditions permit. Most of th

• Proceedings of the KOR-KST Conference
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• 1993.02a
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• pp.70-83
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• 1993

• Journal of the Korean Mathematical Society
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• v.33 no.1
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• pp.57-68
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• 1996

In the classical analysis there are various theorems which permit us to interchange limits and infinite sums, limits and integrals, integrals and infinite sums, etc. The infinite products as well as the infinite series play an important role in different branches of mathematics.

• Proceedings of KOSOMES biannual meeting
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• 2017.04a
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• pp.47-48
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• 2017

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.05a
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• pp.189-190
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• 2012

• Journal of the Korean Institute of Rural Architecture
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• v.15 no.4
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• pp.1-8
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• 2013

The Rural Housing Standard Plans for improving the quality of life and housing stability in rural areas has been developed 87 types from 1994 to 2012. However, some types of Plans do not satisfy the current legal standard in accordance with social and legal changes. Standard plans has the same effect as a building permit, and replace it, so legal suitability of Plans is an important. Therefore, it is required the suitability analysis on the legal standards of Rural Housing Standard Plans. The Purpose of this study is to derive improper types and items of the Rural Housing Standard Plans on the legal standards. In this study, we analyzed its suitability on the legal standards(law on fire-fighting system installation and safety management, energy saving design criteria for buildings, structural checklist for small buildings, the types of drawing for building permit) in accordance with "rules for the operation of standard plans". And we analyzed the utilization of the Rural Housing Standard Plans through downloads from welchon portal.

• Journal of Advanced Marine Engineering and Technology
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• v.13 no.1
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• pp.57-68
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• 1989

This paper treats the analytical and experimental studies on the improvement of commutating circuit for the speed control of DC motor. A simple circuit composed of R, L and C elements is proposed here for switching off power SCR carrying the load current. The real important in this chopper circuit is to determine the reasonable values of commutating circuit constants. In this paper, the reasonable values of the commutating circuit constants are basically determined on a view point of commutating performances in the given circuit model and must satisfy the following conditions. The first, the peak commutating current should be larger than the anticipated maximum load current. The second, the circuit turn-off time (tc) must be longer than the SCR turn-off time (tq). The third, the resistor should be enough large to permit the current to be neglected in the analysis of the commutation circuit, as well as be enough small to permit to charge the capacity voltage (Ec) to the half the value of source voltage (E) before the next communication cycle is initiated. The last, the period of chopping signal must be the least possible multiple of the damping vibration period of commutating circuit. The improved chopper circuit used in the experiment under unloaded condition was composed to meet the reasonable conditions mentioned above, and a successful commuting performance was achieved without failure. Several types of microprocessor having a different value of CPU speed individually have been applied to the experiment under the loaded conditions. Also it shows that the faster the speed of CPU is, the more stable the commutation turns out.

• Journal of Environmental Health Sciences
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• v.32 no.2 s.89
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• pp.126-131
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• 2006

The objective of this study was monitoring of genetically modified soybean by PCR and ELISA. We collected 60 soybean samples from the open markets located in Western Gyeongnam (Sacheon, Hamyang, Hadong, Sanchung, Uiryung, Geochang, and Hapcheon). A total of 60 soybeans was examined and 14 genetical modified soybean (GMS) were detected by PCR. The GMS rate of selling soybean in Uiryung, Hadong, Sacheon, and Hapcheon was 50.0%, 37.5%, 33.3% and 25%, respectively. The 7 of 14 GMSs were positive by ELISA and most of positive samples were below 3% GMS but 1 (Uiryung 1) of the positive samples was over the 3% which is maximum permit limit in Korea. These results mean that merchants of open market did not express for selling soybean mixed with GMS, so consumers did not recognize GMO. Therefore, we thought that education of GMO for merchant of open market need to recognize about GMO maximum permit limit.