• Proceedings of the Korean Aquaculture Society Conference
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• 2003.10a
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• pp.76-77
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• 2003

Olive flounder Paralichthys olivaceus larvae and early juveniles were reared for 43 days after hatching in order to observe the effects of starvation during development and metamorphosis. Morphological, histological and biochemical measurements were made to assess the nutritional condition during growth and starvation from pre-matamorphic through post-metamorphic phases. Two groups of fish were compared ; one with sufficient food supply and one under continuous starvation until death. Among morphometric analyses, both ratios of body height at anus/head height and pre-/post-anal lengths appeared to be sensitive to starvation during which substantial reduction was observed within a day of food deprivation. Histological variables as intestinal and rectal epithelial heights and gall bladder volume changed significantly with onset of starvation. The gut epithelial heights of starving fish decreased with advances in starvation, although they fluctuated during mid-metamorphic phase. In contrast, gall bladder volume increased remarkably soon after starvation. Ontogenetic changes in both gut epithelial height and gall bladder volume were evident, those associated with settlement and/or completion of metamorphosis. Abrupt decrease in the RNA/DNA ratios of starving fish were found right after onset of starvation. Even in the fed fish marked fluctuations in its ratios during metamorphosis were observed, evident by decreasing from late-metamorphic to post-metamorphic stages. These findings suggest that a combination of morphologically and histologically sensitive characteristics, and biochemical measurement could be utilized as a measure to evaluate nutritional condition related to starvation in wild olive flounder larvae and juveniles.

• Journal of Magnetics
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• v.21 no.3
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• pp.450-459
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• 2016

Experimental results and data of numerical simulations are presented, concerning generation of wideband radio frequency (RF) oscillations in a nonlinear transmission line (NLTL) which contains a pre-magnetized core of ferrite material. Emphasis is made on the means for extracting the RF signal from the line, in order to radiate it into free space. Antennas of two types that can be used for the purpose are considered, both featuring a coaxial design. This permits availing of the principal advantages of coaxial systems, such as operation in the mode of a traveling TEM wave; wide range of the transmitted frequencies, and a reasonably simple design. The antennas studied, specifically a disc-cone dipole (DCD) and an impulse reflector antenna ('Half-IRA', or HIRA type) differ significantly in effective width of the radiated spectrum and in spatial characteristics of the radiated field in far region.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.05a
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• pp.129-131
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• 2011

An 6.4-Gb/s/channel 4-PAM transceiver is designed for a high speed memory application. The asymmetric 4-PAM signaling scheme is proposed to increase the voltage and time margins, and reduces the reference noise effect in a receiver by 33%. To reduce ISI in a channel, 1-tap pre-emphasis of a transmitter is used. The proposed asymmetric 4-PAM transceiver was implemented by using 0.13um 1-poly 6-metal CMOS process with 1.2V supply. The active area and power consumption of 1-charmel transceiver including a PLL are $0.294um^2$ and 6mW, respectively.

• Journal of Korean Elementary Science Education
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• v.31 no.2
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• pp.135-145
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• 2012

In this study, we developed an efficient in-service teachers training program, which could help the professional development of science gifted teachers. The characteristic feature of this in-service training program was to put great emphasis on interaction between fellow teachers. With this program, teachers could share their experiences and informations about gifted education. The program consisted of 4 interaction modules: 'the module of interaction at the pre-planning', 'the module of interaction in the small group', 'the module of interaction at the plan of application', 'the module of interaction at the practical exercise'. In this study, we analyzed the interaction between science gifted education teachers in 'the module of interaction at the pre-planning'. We analyzed the interaction between science gifted education teachers in 'the module of interaction at the pre-planning'. Each teachers got 17.2 correction opinions from peer teachers. They accepted 79.2% opinions among them and refused the other opinions (20.8% opinions). In the analysis of 'program process', the interactions for the improvement about 'the acquirements of knowledge and function' step were 41.9% and the interactions for the improvement about 'plan and exploration' step were 30.5%. In the analysis of 'program domain', the interactions about 'method of teaching and learning' were 41.9%. The interactions about 'program step' were 28.6% and the interactions about 'learning contentsh were 24.8%. With these results, we discussed the features of interaction between science gifted education teachers and proposed the improvement of in-service training program for elementary science gifted teachers.

• The Journal of the Acoustical Society of Korea
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• v.11 no.2
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• pp.73-84
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• 1992

This paper studies noise subtraction methods and distance measures for speech recognition in a noisy environment, and investigates noise robustness of the distance measures applied to the problem of isolated word recognition in white Gaussian and colored noise (vehicle noise) environments. Noise subtraction methods which can be used as a pre-processor for the speech recognition system, such as the spectral subtraction method, autocorrelation subtraction method, adaptive noise cancellation and acoustic beamforming are studied, and distance measures such and Log Likelihood Ratio ($d_{LLR}$), cepstral distance measure ($d_{CEP}$), weighted cepstral distance measure ($d_{WCEP}$), spectral slope distance measure ($d_{RPS}$) and cepstral projection distance measure ($d_{CP},\;d_{BCP},\;d_{WCP},\;d_{BWCP}$) are also investigated. Testing of the distance measures for speaker-dependent isolated word recognition in a noisy environment indicate that $d_{RPS}\;and\;d_{WCEP}$ which weigh higher order cepstral coefficients more heavily give considerable performance improvement over $d_{CEP}and\;d_{LLR}$. In addition, when no pre-emphasis is performed, the recognizer can maintain higher performance under high noise conditions.

• Proceedings of the Ginseng society Conference
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• 1993.09a
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• pp.155-163
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• 1993

An American ginseng(Panax quillquefolium L) industry has emerged in British Columbia, Canada over the past ten years. Interest has grown very rapidly and with this development, attention is now moving away from field production issues and emphasis is being directed to enhancements in ginseng storage, drying and processing. There is a dearth of knowledge on these aspects even though they are crucial to international competitiveness. Enhancement dicatates the application of a systems approach to optimizing the harvest and post - harvest production system(crop digging, pre - washing cold storage. washing, drying and post - drying storage). Research in British Columbia to date has focussed on drying and storage issues and has resulted in the design of an enhanced commercial drying system. The role of dryer management, loading rates, airflow rates and pre - drying cold storage on American ginseng root drying rates and root quality were examined. From the dryer management experiments, there are distinct advantages to size sorting root to yield optimum drying rates. If unsorted root is used, efficiency is increased if the trays are systematically rotated. Loading rate experiments illustrate that increasing rates above those currently used in commercial dryers are possible without any sacrifice in quality. This has significant implications for commercial drying. Pre - drying cold storage is a most significant tool for managing drying operations. Over a period of six weeks, no discernable decrease in quality was found as a consequence of cold storage. Further, the moisture loss and the associated root surface changes(loss of surface soil in storage for example) provide new challenges for root quality management. Continued research and technological innovation will be crucial in addressing the demanding challenges of the future.

• PNF and Movement
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• v.3 no.1
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• pp.1-15
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• 2005

Objective : The purpose of this study was to evaluate the influence of a community based group exercise intervention on motor functional capacity. To evaluate the immediate(post-treatment) effects after 6-weeks exercise program on the group exercise intervention(PNF and Circuit exercise). Methods : Subjects-Included persons with stroke who were living in the community. Thirty-seven subjects were randomly assigned to the PNF, Circuit exercise and control group participated in a repeated measures design that evaluated the subjects with pre-treatment, post-treatment(6 weeks). Functional ability outcome measures assessed the motor assessment scale(MAS) and EMG. Both treatment groups participated in exercise cJass three times a week for 6 weeks. Group programs focused on balance, functional motor capacity and walking ability. The PNF program was modified PNF pattem and techniques with emphasis on functional tasks when possible, as well as stretching of the more affected limb particularly in the more affected shoulder. The Circuit program with subjects completing practice at a selies of work station as well as participating in walking races and relay with other members of the group. Results : Compared with the control group, the treatment group had larger improvements in the motor function ability after 6 weeks treatment and Post-treatment test scores were more significant than the pre-treatment score. 1. Motor function were assessed by using MAS, sit to stand, walking and upper function were assessed pre-treatment versus post-treatment measures revealed a statically significant(p<.05). There were significant differences between the groups. Compared with the control group, the treatment group had larger improvements. 2. In the treatment groups, demonstrated difference in the electromyographic activation of biceps, triceps, quadriceps and tibialis anterior muscles on the paretic side in the response to the reaching arm movement and stepping motion in stance. The difference in muscle activation improvement were not statically significant. Conclusion : The results of this study showed that the PNF and Circuit group exercise intervention can improve motor functional ability. This study suggests that the PNF and Circuit exercise programs is appropriate for community-based group exercise principles. It leads to gain and maintain potential function for disabled persons after stroke in the community.

• Proceedings of the IEEK Conference
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• 2000.11d
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• pp.203-206
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• 2000

Since the amplitude of voiced fall off at about -20dB/decade, dynamic range is often compressed prior to spectral analysis so that details at weak, high frequencies may be visible. Preemphasizing the speech, either by differentiating the analog speech s$\sub$a(t) prior to A/D conversion or by differencing the discrete-time s(n)=s$\sub$a(nT), compensating for falloff at high frequencies. The most common form of preemphasis is y(n)=s(n)-As(n-1), where A typically lies between 0.9 and 1.0 and reflects the degree of pre-emphasis. In This paper, we proposed that A is adjusted at each time by measuring the slope of envelope in frequency domain.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.9 no.1
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• pp.60-67
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• 2000

An improved disturbance rejection control scheme is presented for minimizing the position error due to the repeatable runout disturbances in high density disk drive systems The proposed control algorithm is capable of attenuating repeatable disturbances which is one of the major detractors to hard disk drive quality and performance. This is achieved by a sys-tematic combination of an optimal feedback component and a feedforward preview component. The feedback component is designed where the emphasis is placed on robustness. The feedforward component is on the basis of a preview control comprised of a measured disturbance signals which leads to better disturbance rejection capabilites. The designed con-troller is applied as a plug-in module to a high density hard disk drive with a pre-existing conventional servo controller. Simulations have been carried out to demonstrate the effectiveness of this control scheme in the reduction of the periodic disturbances.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.644-644
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• 2013

Graphene is a two-dimensional sp2 layer material. Despite the short history in the empirical synthesis of the graphene layers, the academic/industrial unique features have brought highly significant interest in research and development related to graphene-related materials. In particular, the electrical and optical performances have been targeted towards pre-existing microelectronicand emerging nanoelectronic applications. The graphene synthesis relies on a variety of processing factors, such as temperature, pressure, and gas ratios involving H2, CH4, and Ar, in addition to the inherent selection of copper substrates. The current work places its emphasis on the role of experimental factors in growing graphene thin films. The thermally-grown graphene layers are characterized using physical/chemical analyses, i.e., four point resistance measurements, Raman spectroscopy, and UV-Visible spectrophotometry. Ultimately, an optimization strategy is proposed in growing high-quality graphene layers well-controlled through empirical factors.