• Journal of Power Electronics
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• v.11 no.1
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• pp.74-81
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• 2011

The cutoff frequency of the output LC filters of PWM inverters limits the control bandwidth of the converter system while it attenuates voltage ripples that are caused by inverter switching activities. For a selected cutoff frequency of an output LC filter, an infinite number of L-C combinations is possible. This paper analyses the characteristics of output LC filters for PWM inverters terms of the L-C combinations. Practical circuit conditions such as no-loads, full resistive-loads, and inductive-load conditions are considered in the analysis. This paper proposes a LC filter design method for PWM inverters considering both the voltage ynamics and he inverter stack size. An experimental PWM inverter system based on the proposed output LC lter design uideline is built and tested.

• Herbal Formula Science
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• v.19 no.2
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• pp.1-10
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• 2011

Objectives : Since its enactment in 1987, the 56 standard prescriptions covered by insurance have remained unchanged from its original version. In this study, we tried to discover most frequently used herbal combinations by analyzing prescriptions used in actual clinical settings. Methods : We have built Structured Query Language to analyze herbal combination and progressed this analysis through analyzing the frequencies of medicinal herb combinations in medical prescription slips. Results : We have found out that traditional Korean medical doctors use about 13 herbs in a prescriptions and usually use 253 kinds of herb. And We have found out the most frequently used herbal combination. Conclusions : In this study, We can suggest new method to decide what do we need on insurance prescriptions.

• MALSORI
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• no.47
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• pp.15-29
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• 2003

When intonation in French is analysed in terms of a multi-dimentional and hierarchical structure, each of the prosodic units such as accent phrases(having different combinations of the basic tonemes L and H), pre-sentencial and post-sentencial long pauses, intonation phrases(containing boundary intonation), as well as intermediate phrases can be considered being realized on a separate tier. Unlike on the tiers where accent phrases and intonation phrases occur, an intonation rhythm consisting of plateaus is realised on that of intermediate phrases. This intonation rhythm consisting of plateaus is one of the significant factors that lead a basic French metrical rhythm. This paper first shows the types of combinations of the basic tonemes L and H found in French accent phrases. Secondly, this paper examines the roles intermediate phrases and plateaus play in French. Finally, this paper argues that intermediate phrases are the metrical units actually adopted as real utterance units in French.

• Journal of the Korean Society of Tobacco Science
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• v.23 no.2
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• pp.95-102
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• 2001

This study was conducted to obtain the basic information for breeding of burley(N. tabacum cv. burley) and sun-cured tobacco(N. tabacum cv. sun-cured) variety. Two burley(Burley 21, KB 108), and T.I. 1068 and three sun-cured varieties(Yeonbyeon 3, Jaheungyeon and Jaraehong) were diallel crossed and 15 combinations of F$_1$generations were made in 1998, respectively. Six parental varieties, 15 F$_1$s were grown under the complete randomized block design with 3 replications at Chonju Experiment Station, Korea Ginseng & Tobacco Research Institute in 2000. The data of 12 quantitative characters were measured for degree of heterosis. The results obtained are as follows. Heterosis of F$_1$generation was positive in weight per leaf, plant height, stem diameter, yield, leaf length and total alkaloid content. Cross combinations between either Burley 21 or KB 108 and sun-cured varieties showed comparatively high heterosis in each characters.

• Journal of Welding and Joining
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• v.16 no.4
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• pp.63-72
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• 1998

In this study, the effects of the current pulsing conditions, on the spatter generation rate during the $CO_2$ gas metal arc welding (GMAW) were investigated. Normally using the inverter type power supply, of which the welding current waveform was regulated to reduce the spatter generation rate, but in this study pulsing was imposed on the welding current. Observation of the metal transfer phenomena during the pulsed current GMAS indicated that the droplet transfer from the electrode via the short circuit transfer and the repelling transfer mode could be minimized by selecting optimum combinations of pulsing parameters, which include base and peak current, base and pak duration. It was also demonstrated in this study that proper combinations of the pulsing parameters led to reduce generation of spatters during GMAW shielded by $CO_2$ gas.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2010.04a
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• pp.183-185
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• 2010

There are many error sources in GPS signal propagation because the signals do not propagate in vacuum. The GPS observations should be preprocessed before they are used for positioning. The cycle slip and outlier detection algorithms are tested in this study in RINEX level using various linear combinations of the observables. The elbourne-Wubbena (M-W) linear combination has an advantage of long wavelength with low noise, and the geometry-free and ionosphere-free linear combinations are used as well to clean the measurements.

• Journal of Korean Society for Geospatial Information Science
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• v.19 no.2
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• pp.75-83
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• 2011

After 1995, as a part of national geographic information system project, there are a lot of researches about combinations and connections of national geographic information system. However, systematic standard for combinations and connections of geographic information is uncertain, and each organization has different identification system which leads to difficulties in connection of geographic information system. This study suggests repeating method about geographic information objects to grant UFID based on national standards of geographic information system, and analyzes the repeating rate.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.05a
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• pp.126-127
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• 2016

In this research, the optimum combination of fly ash (FA) and blast furnace slag (BS) was deduced by analyzing the performance of high volume supplementary cementitious materials (SCMs) cement mortar depending on various combinations of cement, FA, and BS. As a result, increased workability was shown with increased the portion of FA, while air content, setting time, and compressive strength were decreased.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.21 no.47
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• pp.125-138
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• 1998

In this paper, we investigate the effect of re-entrance to the same work station in a job shop with multiple identical machines. System A is defined as the system in which re-entrance is not permitted, and system B is defined as the system in which re-entrance is permitted. By the analytical result of the queueing network, we find that the two systems have the same queue length distributions and utilizations under FIFO dispatching rule when all parameters are same. Simulation models are developed for various comparisons between the two systems, and simulation experiments are conducted for the combinations of five dispatching rules, two average workloads and two due date allowances. Five performance measures are selected for the comparison. The simulation results show that permitting re-entrance affects for some combinations of system environments.

• Mycobiology
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• v.29 no.3
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• pp.135-141
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• 2001

Differential display of reverse transcription(DDRT)-PCR was conducted to have a profile of the differentially expressed genes during the formation of fruiting body of Lentinus edodes. The lines of L. edodes(ImHyup-1) employed were cultivated in the artificial blocks of sawdust, and the fruiting body was induced from the mycelia or the mass protruded from the brown surface of the sawdust blocks. RNAs were prepared from the four different developmental stages; mycelial, primordial, and stipes and pileus of fruiting body. The fragments of cDNA were synthesized from the combinations of the arbitrary primers and 3' one anchored Oligo-dT primer. Twelve combinations using the primers have been tested, and among them nineteen bands were identified as differentially expressed. Those genes were further analyzed by DNA sequencing and followed by homology search. Characterization of one clone was conducted as a preliminary data and more are under investigation.