• Journal of Korean Library and Information Science Society
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• v.21
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• pp.253-289
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• 1994

The purpose of this study is about the search pattern of LINNET (Library Information Network System) OPAC users by transaction log, maintained by POSTECH(Pohang University of Science and Technology) Central Library, to provide feedback information of OPAC system design. The results of this study are as follows. First, for the period of this analysis, there were totally 11, 218 log-ins, 40, 627 transaction logs and 3.62 retrievals per a log-in. Title keyword was the most frequently used, but accession number, bibliographic control number or call number was very infrequently used. Second, 47.02% of OPAC, searches resulted in zero retrievals. Bibliographic control number was the least successful search. User displayed 2.01% full information and 64.27% local information per full information. Third, special or advanced retrieval features are very infrequently used. Only 22.67% of the searches used right truncation and 0.71% used the qualifier. Only 1 boolean operator was used in every 22 retrievals. The most frequently used operator is 'and (&)' with title keywords. But 'bibliographical control number (N) and accessionnumber (R) are not used at all with any operators. The causes of search failure are as follows. 1. The item was not used in the database. (15, 764 times : 79.42%). 2. The wrong search key was used. (3, 761 times : 18.95%) 3. The senseless string (garbage) was entered. (324 times : 1.63%) On the basis of these results, some recommendations are suggested to improve the search success rate as follows. First, a n.0, ppropriate user education and online help function let users retrieve LINNET OPAC more efficiently. Second, several corrections of retrieval software will decrease the search failure rate. Third, system offers right truncation by default to every search term. This methods will increase success rate but should considered carefully. By a n.0, pplying this method, the number of hit can be overnumbered, and system overhead can be occurred. Fourth, system offers special boolean operator by default to every keyword retrieval when user enters more than two words at a time. Fifth, system assists searchers to overcome the wrong typing of selecting key by automatic korean/english mode change.

• The Journal of the Acoustical Society of Korea
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• v.19 no.7
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• pp.42-47
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• 2000

This paper describes a real-time implementation of a GSM-EFR (Global System for Mobil communications Enhanced Full Rate) speech coder using OakDSP core; a 16bit fixed-point Digital Signal Processor (DSP) by DSP Group, Inc. The real-time implemented speech coder required about 24MIPS for computation and 7.06K words and 12.19K words for code and data memory, respectively. The implemented GSM-EFR speech coder passes all of test vectors provided by ETSI (European Telecommunication Standard Institute), and perceptual speech quality measurement using MNB algorithm shows that the quality of the GSM-EFR speech coder is similar to the one of 32kbps ADPCM. The real-time implemented GSM-EFR speech coder which is the highest bit-rate mode of the GSM-AMR speech coder will be used as the basic structure of the GSM-AMR speech coder which is embedded in MODEM ASIC of IMT2000 asynchronous mode mobile station.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 1999.05a
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• pp.389-393
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• 1999

The exact model of impact ionization events in which has influence on device efficiency, is to be necessary element for device simulation. Recently, a modified Keldysh formula with two set of power exponent of 7.8 and 5.6 is used to simulate carrier transport. This model is, however, not suitable as impact ionization model in low energy range since this ignore direction dependent properties of impact ionization. The impact ionization rate is highly anisotropic at low energy, while it becomes isotropic at higher energy range. Note that impact ionization events frequently occur in high energy range. For calculating impart ionization rate, we use full energy band structure derived from Fermi's golden rule and empirical pseudopotential method. We compare with calculated and experimental value, and investigate direction dependent conduction energy band structure along the direction of <100>, <110> and <111>. We know that the threshold energy of impact ionization is anisotropic and impact ionization rate is very deviated from modified Keldish formula, in relatively low energy range.

• Korean Journal of Medicinal Crop Science
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• v.20 no.5
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• pp.320-330
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• 2012

This study was conducted to investigate the changes of chlorophyll contents, chlorophyll fluorescence, photosynthetic parameters, and leaf growth of Synurus deltoides under different shading treatments. S. deltoides was grown under non-treated (full sunlight) and three different shading conditions (Shaded 88~93%, 65~75%, and 45%~55%). Light compensation point ($L_{comp}$), dark respiration ($D_{resp}$), maximum photosynthesis rate ($Pn_{max}$), photo respiration rate ($P_{resp}$), carboxylation efficiency ($\Phi_{carb}$), and photochemical efficiency were decreased with increasing shading level; However, $CO_2$ compensation point ($CO_{2\;comp}$), total chlorophyll content, and specific leaf area (SLA) were shown the opposite trend. S. deltoides under 88~93% treatment showed the lowest photosynthetic activity such as maximum photosynthetic rate ($Pn_{max}$), photochemical efficiency, and $CO_2$ compensation point ($CO_{2\;comp}$). Therefore, photosynthetic activity will be sharply decreased with a long period of 8~12% of full sunlight. With the shading level decreased, carotenoid content and non-photochemical fluorescence quenching (NPQ) increased to prevent excessive light damage. This result suggested that growth and physiology of S. deltoides adapted to high light intensity through regulating its internal mechanism.

• Journal of the Korean Society of Propulsion Engineers
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• v.9 no.4
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• pp.1-8
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• 2005

An experimental investigation of a microthruster that uses hydrogen peroxide as a monopropellant is described. The study comprises of preparation method of silver as a catalyst and performance evaluation of a mesoscale reactor. Reduction of silver in $H_2\;at\;500^{\circ}C$ resulted in the best reactivity of all the treatment method tested. A mesoscale reactor was built to find the optimum configuration for full decomposition of propellant. The catalyst bed was made of a glass wafer substrate sputtered with silver and had a length of 20 mm. We measured the conversion rate with varying feed rate of $H_2O_2$ and preheating temperature. With the feed rate of $H_2O_2$, the space time within the reactor varies as well. For the bed length of 20 mm, space time more than 480 s was required for full conversion.

• JSTS:Journal of Semiconductor Technology and Science
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• v.13 no.4
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• pp.303-317
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• 2013

Two novel clocking strategies for a high-speed multi-channel serializer-deserializer (SERDES) are proposed in this paper. Both of the clocking strategies are based on groups, which facilitate flexibility and expansibility of the SERDES. One clocking strategy is applicable to moderate parallel I/O cases, such as high density, short distance, consistent media, high temperature variation, which is used for the serializer array. Each group within the strategy consists of a full-rate phase-locked loop (PLL), a full-rate delay-locked loop (DLL), and two fixed phase alignment (FPA) techniques. The other is applicable to more awful I/O cases such as higher speed, longer distance, inconsistent media, serious crosstalk, which is used for the deserializer array. Each group within the strategy is composed of a PLL and two DLLs. Moreover, a half-rate version is chosen to realize the desired function of 1:2 deserializer. Based on the proposed clocking strategies, two representative ICs for each group of SERDES are designed and fabricated in a standard $0.18{\mu}m$ CMOS technology. Measurement results indicate that the two SERDES ICs can work properly accompanied with their corresponding clocking strategies.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.20 no.2
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• pp.207-216
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• 2007

The flexural behavior of steel composite beam with built-up cross-section by bolt connection is presented in this paper. The composite effect due to bolt-connetion and friction between steel plate are considered to investigate the flexural behavior of steel composite beam. The displacement, bending stresses and shear stresses according to composite rate are calculated by F.E. analysis and these results are compared to the analytical values of non interaction beam and full interaction beam. As a result of analysis, the behavior of composite beam is more dependant on the composite rate than the friction of the steel plate. When the composite rate reaches $50{\sim}60%$, the behavior of composite beam is similar to that of fully composite beam.

• Korean Journal of Medicinal Crop Science
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• v.21 no.5
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• pp.394-400
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• 2013

This study was carried out in order to examine the germination characteristics of Atractylodes japonica seeds, and it was to develop the more efficient pre-treatment and production system of the seeds. Experiment was performed by two ways-temperature control (10, 15, 20, $25^{\circ}C$) and shading treatment (full sunlight, 35, 50, 75, 95% of full sunlight). Seed pre-treatment before the each experiment was carried out by temperature (with low temperature and wetting treatment (LTW) for 0, 15, 30, 45 and 60 days) and shading treatment (with drying at room temperature (DRT), drying at low temperature (DLT) and water soaking (WS) for 48 hours). Seeds of A. japonica were germinated well under temperature control (overall 85.3~100%), especially high temperature. And, the seeds pre-treated with LTW for 45 days germinated with a 100% success rate. Under the surveying shading treatment, the highest germination rate was 95.8% with DRT and overall 63.2~95.8%. Germination rate under seeds with WS was 63.2~7.8%. As a result of surveying the whole experiment, A. japonica seeds don't need to pre-treat cause of high germination, but if it is performed with LTW for a certain period of time, it would be more productive.

• Journal of the Korean Dietetic Association
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• v.14 no.4
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• pp.361-370
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• 2008

The purpose of this study is to provide basic data for the medical nutrition therapy of premature infants. The general characteristics, presence of metabolic disorders, hematological profile and feeding methods were compared between the premature infant group (<37 weeks, n=61) and the full-term infant group (37$\sim$42 weeks, n=165). Birth weight (p<0.0001), birth length (p<0.005), head circumference (p<0.0001), chest circumference (p<0.0001), and Apgar scores (p<0.0001) of the neonates were all statistically lower in the premature infant group. Jaundice cases (p<0.0001) were statistically higher in the premature infant group. White blood cell counts (WBC: p<0.005), mean corpuscular volume (MCV: p<0001), mean corpuscular hemoglobin (MCH: p<0.005), mean corpuscular hemoglobin concentration (MCHC: p<0.005), and mean platelet volume (MPV: p<0.05) were statistically lower in the premature infant group. The premature infant group were fed a higher rate of premature formula than breast milk and the full-term infant group were fed a high rate of human milk at a higher rate, showing differences in kinds of feeding methods (p<0.0001) between the two groups. An infant's birth weight showed a significantly positive correlation with the infant's birth length (p<0.0001), head circumference (p<0.0001), chest circumference (p<0.0001), and Apgar scores(p<0.0001). The birth length also showed a significantly positive correlation with both head circumference (p<0.05) and chest circumference (p<0.05). Head circumference showed a significantly positive correlation with chest circumference (p<0.0001) and Apgar scores (p<0.0001). Chest circumference showed a significantly positive correlation with Apgar scores (p<0.0001). In addition, the Apgar Score at of 1 minute after birth showed a significantly positive correlation with the Apgar score at of 5 minute after birth (p<0.0001).

• Plant Biotechnology Reports
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• v.3 no.3
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• pp.259-266
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• 2009

A plantlet regeneration protocol was developed on pot-grown mature plants of Elaeocarpus robustus Roxb. cv. Dwarf from nodal and leaf explants. The best yield of adventitious shoots was achieved from the leaf-derived calli in a modified MS ($MMS_1$, half strength of major salts, full strength of minor salts, and vitamins) medium containing $4.0{\mu}M$ BA + $4.0{\mu}M$ Kn + $0.5{\mu}M$ NAA + 15% coconut water (CW). The shoot multiplication rate was amplified about twofold per culture after the addition of 15% CW to the medium. The rate of shoot multiplication reached maximum at the 5th subculture, and it maintained this rate throughout the 3 subsequent subcultures. The best rooting in vitro was investigated by subculturing the microcuttings in an $MMS_2$ (half strength of both major salts and minor salts and full strength of vitamins) medium containing $1.0{\mu}M$ IBA in the dark for one initial week at $30^{\circ}C$, followed by subculturing them in a plant-growth regulator (PGR)-free medium in the light. The plantlets raised in vitro were successfully established under ex vitro conditions.