• Korean Journal of Child Studies
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• v.7 no.1
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• pp.67-84
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• 1986

The purpose of the present research was to investigate cross-modal transfer, especially tactual-to-visual transfer in infancy and to study the relation between failure of cross-modal transfer performance and length of familiarization period. The subjects of this study were 60 infants, 10 boys and 10 girls at each level: six, nine, and twelve months of age. All were normal, healthy, full-term babies. The mothers' educational achievement was controlled at more than 12 years of schooling. There were two separate experimental conditions, one 30-sec and one 60-sec familiarization period. Each experimental condition consisted of a tactual familiarization and a visual recognition memory test. Each child was presented with these 2 sets of cross-modal stimuli in one of the 2 experimental conditions. Infants' visual responses in the visual recognition memory test were videotaped for 20 seconds. Visual fixation time to novel and familiar stimuli was observed throughout the test. The data was analyzed with t-test, percentage of total fixation time to novel stimuli, and ANOVA. The results showed that: 1) Significant differences were found in the cross-modal transfer performance from touch to vision between the 3 age groups. This is, 6 and 9 month old infants didn't show cross-modal transfer in the 30-sec condition, but 12 month old infants did show cross-modal transfer in the 30-second. 2) In all 3 age groups, no significant differences were found in cross-modal transfer performance between the two conditions.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1997.06a
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• pp.174-182
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• 1997

The technology of Semi-Solid Forging (SSF) has been actively developed to fabricate near-net-shape products using light and hardly formable materials. Generally, the SSF process is composed of slug heating, forming, compression -holding and ejecting step. After forming step in SSF, the slug is compressed during a certain holding time in order to be completely filled in the die cavity and be accelerated in solidification rate. The compression holding time that can affect microstructural characteristics and shape of products is important to make decision, where it is necessary to find overall heat transfer coefficient properly which has large effect on heat transfer between slug and die. This paper presents the procedure to predict compression holding time of obtaining the final shaped part with information of temperature and solid fraction for a cylindrical slug at compression holding step in closed-die compression process using heat transfer analysis considering latent heat by means of finite element method. The influence of the predicted compression holding time on microstructural characteristics of products is finally investigated by experiment.

• Bulletin of the Korean Chemical Society
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• v.24 no.11
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• pp.1675-1679
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• 2003

The photodynamics of excited-state intramolecular proton transfer reaction of 1-hydroxyanthraquinone (1-HAQ) and 1-deuterioanthraquinone was investigated in toluene with time-resolved emission and femtosecond transient transmittance techniques at room temperature. The temporal profiles of transient transmittance of 1-HAQ could be well described with multi-decaying time constants. The ultrafast time constant within ca. 260 fs reflects the dynamics of proton transfer. The decay component of 2 ps is assigned to an additional proton translocation process induced by the intramolecular vibrational relaxation, whereas the decay component of 18 ps is assigned to the vibrational cooling process, while the long component (200 ps) can be explained in terms of the relaxation from excited-state keto-tautomer to its ground state. Time-resolved anisotropy decay dynamics and isotope effects on the photodynamics reveals that the ESIPT from enol-tautomer to keto-one of 1-HAQ is barrierless reaction and coupled to a vibrational relaxation process.

• International Journal of Korean Welding Society
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• v.4 no.1
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• pp.15-22
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• 2004

Metal transfer behavior of three shielded metal arc welding electrodes, AWS El1018, E6013 and E6010, were investigated through the characterization of size distribution of droplets and measurement of arc voltage signals. Of the three electrodes, Ell018 electrode showed the largest droplet size with the smallest amount of spatter, while E6010 electrode showed the smallest droplet size with the largest amount of spatter. Even though Ell0l8 electrode showed a good agreement between the frequencies of voltage drop in FFT processed voltage signals and the transfer rate of droplets, E6013 and E6010 electrodes showed weaker correlation because of their dominant explosive transfer behavior. The type of cathode used and electrode baking time also influenced the metal transfer behavior. Compared to bead-on-plate welding using steel plate as a cathode, welding on a water-cooled copper pipe showed less short-circuiting and higher melting rate in all electrodes because of higher arc potential and/or anode drop. When baked for a long time, E6010 electrode showed much more stable arc with less short-circuiting and explosion due to the loss of gas formation ingredients.

• Journal of Electrical Engineering and Technology
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• v.7 no.6
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• pp.876-883
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• 2012

The paper investigates three types of transfer function methods for detecting displacements of winding in a model transformer. To acquire these transfer functions, the measuring method of input voltage, current and its response is used in impulse method. The applied impulse voltages had three rising times, which were short rising time (less than 0.6 ${\mu}s$), medium rising time (about 0.8 ${\mu}s$) and long rising time (about 1 ${\mu}s$) in front waves. Every 10 measurements of voltage and current waves were averaged from 50 measurements of voltage and current waves. These transfer functions were tested in normal, 24mm elevated and 48mm elevated windings conditions and were analyzed with correlation coefficients and spectrum deviations. In the analysis, the results depend on the types of transfer functions and the rising times of input voltages.

• Journal of Institute of Control, Robotics and Systems
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• v.5 no.8
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• pp.889-897
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• 1999

This paper deals with a problem searching a target transfer function to meet the time-domain specifications for feedback system with given plant transfer function. For the Type I system, we first define three forms of transient response to unit step input, which are named by F, M, S-type. These are charaacterized as follows ; F-type has fast initial response and slow approach to the steady sate after reaching at 90% of the steady state value, S-type has slow initial response but fast approach to the steady state, and M-type is denoted by highly smooth response between F-type and S-type. Three prototypes corresponding to each form are proposed, time. For the order $n{\geq}4$, after determining admissible root structures of target characteristic polynomials empirically and expressing such polynomial coefficients by using special parameters ${\gamma}_i$ and $\epsilon$, the optimal prototypes that minimize the integral of the squared of the modified errors(ISME) have been obtained. Since the step responses of these prototypes have almost same wave forms irrespective to the order, the desired settling time or the rise time can be converted into the equibalent time constant $\tau$ and thus it is easy to obtain a target transfer function. It is shown through a design example that the present prototype is very useful for meeting the time-domain specifications and has been compared with different methods with a viewpoint of pertinence.

• Korean Management Science Review
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• v.26 no.1
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• pp.93-112
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• 2009

In this paper, a model is presented to estimate a cycle time for completing an operation in a new type of AS/RS which can handle very heavy loads by separating the mechnisms for vertical and horizontal movements. Considering loading/unloading time between devices, we generalize the previous work, Hu et al. [9], which neglected the transfer time. Through the numerical experiments for various situations, we find that the difference of the cycle times between two models is fairly large and conclude that the transfer time between devices cannot be neglected at all.

• Journal of Embryo Transfer
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• v.20 no.1
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• pp.9-15
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• 2005

This study was conducted to investigate the effects of various factors of practitioner's techniques such as skill, difficulty, consumed time, implantation depth, bleeding and altering of implant location, on pregnancy and abortion after transfer of in vitro produced Korean Native Cow embryos. The pregnancy rate of skilled transfer $(54.2\%)$ was significantly higher than that of unskilled transfer $(37.9\%)$, of 2/3 $(46.9\%)$ location in uterus was significantly higher than in 1/2 $(39.5\%)$ or 4/5 $(38.0\%)$ uterus, and of altering implantation location $(52.9\%)$ was significantly increased. There were no difference in pregnancy among the groups of difficulty of transfer, consumed time and bleeding of uterus. The abortion rates from skill, difficulty of transfer, implantation depth, consumed time, bleeding of uterus and altering of location were not differ.

• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.3
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• pp.487-494
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• 2020

In this paper, we propose a current memory circuit design that reduces static power consumption and maximizes the advantages of current mode signal processing. The proposed current memory circuit minimizes the problem in which the current transfer error increases as the data transfer time increases due to clock-feedthrough and charge-injection of the existing current memory circuit. The proposed circuit is designed to insert a support MOS capacitor that maximizes the Miller effect in the current transfer structure capable of low-power operation. As a result, it shows the improved current transfer error according to the memory time. From the experimental results of the chip, manufactured with MagnaChip / SK Hynix 0.35 process, it was verified that the current transfer error, according to the memory time, reduced to 5% or less.

• Journal of Trauma and Injury
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• v.26 no.4
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• pp.261-265
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• 2013

Purpose: The aim of this study is to evaluate the transfer pattern of multiple trauma patients after acute phase management and to determine whether the time between the surgeon's decision and the actual transfer correlates with the patient's insurance type. Methods: Three hundred ninety-two(392) multiple trauma patients visited the emergency room from January 2011 to April 2013. Among the 143 patients who were admitted by a trauma surgeon, 47 were transferred to another hospital after acute phase management. The age, gender, trauma mechanism, Revised trauma score (RTS), Injury severity score (ISS), insurance type, length of ICU stay and hospital stay were analyzed through a retrospective chart review. Results: The mean age was 47.7 years, and traffic accident was the most common mechanism(26, 55.3%). The mean RTS and ISS were 6.93 and 22.7, respectively. Twenty-five patients(53%) were covered by National health insurance, and 20 patients(42.6%) were covered by automobile insurance. Patients were transferred to primary (4.3%), secondary(80.9%), tertiary(4.3%) and care(10.6%) hospitals. The mean time from transfer decision to actual transfer was significantly longer for patients who were covered by automobile insurance than it was for patients who were covered by national health insurance (p=0.038). Conclusion: An appropriate transfer system at the end of acute phase care is essential for managing trauma centers with limited staffing and facilities. In addition, the mean time from transfer decision to actual transfer seemed to be definitely related to the type of insurance covering the patient.