• Journal of the Korean Geotechnical Society
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• v.27 no.3
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• pp.41-54
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• 2011

The present study analyzes the stability of waterfront quay wall under the combined action of earthquake and tsunami. Adopting the limit equilibrium method, the stability of waterfront quay wall is checked for both the sliding and overturning. Forces due to tsunami are compared with the proposed formula and the 3-D one-field Model for immiscible TWO-Phase flows (TWOPM-3D). Variations of the stability of wall are also proposed by the parametric study including tsunami water height, horizontal seismic acceleration coefficient, internal friction angle of soil, friction angle between the wall and the soil and the pore water pressure ratio. The present study about the stability of wall is also compared with the case when earthquake and tsunami are not considered. As a result, the result of numerical analysis about the tsunami force is similar to that of proposed formula. When earthquake and tsunami are simultaneously considered, the stability of wall in passive case significantly decreases and tsunami forces in active case are affected as a resistance force on the wall and so the stability of wall increases.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.7
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• pp.1003-1009
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• 2000

Four young swamp buffalo cows of similar age ranging in body weight (W) between 280 to 380 kg and trained for doing physical exercise were used in two consecutive experiments, each using a latin square design, to determine energy expenditure for draught. The experiments consisted of field trials using 4 levels of work load, i.e. no work as control and loads amounting 450 to 500 Newton (N) continuous traction for respectively 1, 2 and 3 h daily for 14 consecutive days for experiment 1, and no work, traction loads equaling 5, 10 and 15% of W for 3 h daily for 14 days for experiment 2. Heart rate during rest and exercise was monitored using PE-3000 HR monitor. Cows were fed only king grass (Penisetum purpuroides) ad libitum and were subjected to balance trials. Body composition was estimated in vivo by the body density method and daily energy expenditure (EE) was calculated from ME minus RE. RE was calculated from the changes in body-protein and -fat measured before and immediately after the 14 d experimental period assuming an energy equivalent of 39.32 MJ/kg fat and 20.07 MJ/kg protein. $E_{exercise}$ ($EE_{work}\;-\;EE_{resting}$), which was the energy spent for doing the traction during 1, 2 and 3 h was 7.13, 15.45 and 19.90 MJ, respectively. $EE_{work}$ for the 1 h treatment group was 39.75 MJ/d equivalent to 1.30 times $EE_{resting}$. The values for the 2 and 3 h treatment groups were 1.75 and 1.86 times resting energy requirement, respectively. Absolute efficiency of work in all exercise trials of experiment 2 was around 27.28%. The increases of daily $E_{exercise}$ values were correlated to elevation of heart rate (HR) according to the equation $E_{exercise}=(0.270HR^{0.363}\;-\;1)$ MJ, while draught force related to heart rate according to the equation DF (N)=6.66 HR - 361.62. Blood glucose and triglyceride levels were gradually elevated with time during the course of exercise. Mean values of blood glucose were 91.7, 115.0 and 116.2 mg/dl for cows after 1, 2 and 3 h pulling loads at 15% W respectively as compared to 88.2 mg/dl prior to work. In the same order and treatment, mean blood triglyceride concentrations were 13.5, 13.3 and 14.8 mg/dl, and 11.5 mg/dl for control. For blood lactate, the values were 1.68, 1.63 and 1.66 mM, and 0.80 mM for control. Glucose was used as the major source of energy during the initial phase of exercise, but for prolonged work, fat will replace carbohydrate as the main substrate. Accumulation of lactate persisted for some time at the end of the exercise trials.

• Korean Parent-Child Health Journal
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• v.4 no.1
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• pp.35-55
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• 2001

Recently attention has been focused on the effects of early intervention, or its lack, on both normal and preterm infants. Particularly numerous studies suggest that premature infants are not necessarily understimulated but instead are subjected to inappropriate stimulation. Developmental support and sensory stimulation have become clinical opportunities in which nursing practice can impact on the neurobehavioral outcome of premature infants. Developmental care has been widely accepted and implemented in neonatal intensive care units across the country. Increasingly, attention and concern in caring for low-birth-weight infants and premature infants has led clinicians in the field to explore the effects of a complex of interventions designed to create and maintain a developmentally supportive environment; to provide age-appropriate sensory input; and to protect the infant from inappropriate, excessive and stressful stimulation. The components of developmental care include modifications of the macro-environment to reduce NICU light and sound levels, care clustering, nonnutritive sucking, and containment strategies, such as flexed positioning or swaddling. Sensory stimulation of the premature infants is presented to standardize the modification of a developmental intervention based on physiologic and behavioral cues. The most appropriate type of stimuli are those that are sensitive to infant cues. Evaluation of infant physiological and behavioral responds to specific intervention stimuli may help to identify more appropriate interventions based on infants' cues. A critical question confronting the clinician is that of determining when the evidence supporting a change in practice is sufficient to justify making that change. There are acknowledged limitations in the current studies. Many of the studies examined had small sample sizes; used nonprobability sampling; and used a phase lag design, which introduces the possibility of threats to internal validity and limits the generalizability of the results. Although many issues regarding the effects of developmental interventions remain unresolved, the available research base documents significant benefits of developmental care for LBW infants in consistent outcomes, without significant adverse effects. Particularly, although the individual studies vary somewhat in the definition of specific outcomes measured, instrumentation used, time and method of data collection, and preparaion of the care providers, in all studies, infants receiving the full protocol of individualized developmentally supportive care had improvements in some aspect of four areas of infant functioning: level of respiratory or oxygen support, the establishment of oral feeding; length of hospital stay, and infant behavioral regulation. In summary, based on the available literature, individualized developmental intervention should be incorporated into standard practice in neonatal intensive care. And this implementation needs to be coupled with ongoing research to evaluate the impact of an individualized developmental care programs on the short- and long-tenn health outcomes of LBW infants.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.362-362
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• 2014

Atomic layer deposition (ALD) can be regarded as a special variation of the chemical vapor deposition method for reducing film thickness. ALD is based on sequential self-limiting reactions from the gas phase to produce thin films and over-layers in the nanometer scale with perfect conformality and process controllability. These characteristics make ALD an important film deposition technique for nanoelectronics. Tantalum pentoxide ($Ta_2O_5$) has a number of applications in optics and electronics due to its superior properties, such as thermal and chemical stability, high refractive index (>2.0), low absorption in near-UV to IR regions, and high-k. In particular, the dielectric constant of amorphous $Ta_2O_5$ is typically close to 25. Accordingly, $Ta_2O_5$ has been extensively studied in various electronics such as metal oxide semiconductor field-effect transistors (FET), organic FET, dynamic random access memories (RAM), resistance RAM, etc. In this experiment, the variations of chemical and interfacial state during the growth of $Ta_2O_5$ films on the Si substrate by ALD was investigated using in-situ synchrotron radiation photoemission spectroscopy. A newly synthesized liquid precursor $Ta(N^tBu)(dmamp)_2$ Me was used as the metal precursor, with Ar as a purging gas and $H_2O$ as the oxidant source. The core-level spectra of Si 2p, Ta 4f, and O 1s revealed that Ta suboxide and Si dioxide were formed at the initial stages of $Ta_2O_5$ growth. However, the Ta suboxide states almost disappeared as the ALD cycles progressed. Consequently, the $Ta^{5+}$ state, which corresponds with the stoichiometric $Ta_2O_5$, only appeared after 4.0 cycles. Additionally, tantalum silicide was not detected at the interfacial states between $Ta_2O_5$ and Si. The measured valence band offset value between $Ta_2O_5$ and the Si substrate was 3.08 eV after 2.5 cycles.

• Economic and Environmental Geology
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• v.40 no.5
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• pp.563-574
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• 2007

Laser induced breakdown spectroscopy (LIBS) is a recently developed analytical technique that is based upon the measurement of emission lines generated by atomic species close to the surface of the sample, thus allowing their chemical detection, identification and quantification. With powerful advantages of LIBS compared to the conventional analytical methodology, this technique can be applied in the detection of heavy metals in the field. LIBS allows the rapid analysis by avoiding laborious chemical steps. LES have already been applied for the determination of element concentration in a wide range of materials in the solid, liquid and gaseous phase with simplicity of the instrument and diversity of the analytical application. These feasibility of rapid multi elemental analysis are appealing proprieties for the in-situ analytical technique in geochemical investigation, exploration and environmental analysis. There remain still some limitations to be solved for LIBS to be applied in soil environment as an in-situ analytical technology. We would like to provide the basic principle related to the plasma formation and laser-induced breakdown of sample materials. In addition, the matrix effect, laser properties and the various factors affecting on the analytical signal of LIBS was dealt with to enhance understanding of LIBS through literature review. Ultimately, it was investigated the feasibility of LIBS application in soil environment monitoring by considering the basic idea to enhance the data quality of LIBS including the calibration method for the various effects on the analytical signal of LIBS.

• Journal of Biomedical Engineering Research
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• v.23 no.4
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• pp.269-279
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• 2002

When we inject a current into an electrically conducting subject such as a human body, voltage and current density distributions are formed inside the subject. The current density within the subject and injection current in the lead wires generate a magnetic field. This magnetic flux density within the subject distorts phase of spin-echo magnetic resonance images. In Magnetic Resonance Current Density Imaging (MRCDI) technique, we obtain internal magnetic flux density images and produce current density images from $\bigtriangledown{\times}B/\mu_\theta$. This internal information is used in Magnetic Resonance Electrical Impedance Tomography (MREIT) where we try to reconstruct a cross-sectional resistivity image of a subject. This paper describes numerical techniques of computing voltage. current density, and magnetic flux density within a subject due to an injection current. We use the Finite Element Method (FEM) and Biot-Savart law to calculate these variables from three-dimensional models with different internal resistivity distributions. The numerical analysis techniques described in this paper are used in the design of MRCDI experiments and also image reconstruction a1gorithms for MREIT.

• Journal of the Korean Magnetics Society
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• v.19 no.6
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• pp.209-215
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• 2009

M-type barium ferrite (BaFe12O19) powders were synthesized through the co-precipitation method. Starting material composition $Fe^{3+}:\;Ba^{2+}$ mole ratio was fixed as 8 and the relative amount of $Fe^{3+}$ and $Ba^{2+}$ was controlled. Structure and magnetic properties and powder morphology were investigated using XRD, SEM, VSM. Powder showing high coercivity and small magnetization was obtained at pH8 and $Fe_{3+}:\;Ba_{2+}$ of 12 : 1.5. Small magnetization value was originated from the existence of ${\alpha}-Fe_2O_3$. Single-phase Mtype barium ferrite were obtained regardless of the heat treatment condition and the amount of $Fe_{3+}\;and\;Ba_{2+}$ at pH$\approx$10. The largest value of magnetization (55.7 emu/g) under investigation were obtained when $Fe_{3+}:\;Ba_{2+}$ of 13.6 : 1.7 and furnace cooled powder in $O_2$. Particle size of powder was in the range of 50~200 nm.

• Journal of the Korean Ceramic Society
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• v.50 no.6
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• pp.353-358
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• 2013

The hot corrosion behavior of plasma sprayed 4 mol% $Y_2O_3-ZrO_2$ (YSZ) thermal barrier coatings (TBCs) with volcanic ash is investigated. Volcanic ash that deposited on the TBCs in gas-turbine engines can attack the surface of TBCs itself as a form of corrosive melt. YSZ coating specimens with a thickness of 430-440 ${\mu}m$ are prepared using a plasma spray method. These specimens are subjected to hot corrosion environment at $1200^{\circ}C$ with five different duration time, from 10 mins to 100 h in the presence of corrosive melt from volcanic ash. The microstructure, composition, and phase analysis are performed using Field emission scanning electron microscopy, including Energy dispersive spectroscopy and X-ray diffraction. After the heat treatment, hematite ($Fe_2O_3-TiO_2$) and monoclinic YSZ phases are found in TBCs. Furthermore the interface area between the molten volcanic ash layers and YSZ coatings becomes porous with increases in the heat treatment time as the YSZ coatings dissolved into molten volcanic ash. The maximum thickness of this a porous reaction zone is 25 ${\mu}m$ after 100 h of heat treatment.

• Journal of the Korean Society of Costume
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• v.55 no.1 s.91
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• pp.25-42
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• 2005

Costume is a formative art expressed by active human unlike the field of other living formativeness, and an expression of social actions based on a style of culture in a period. Therefore, costume has a deep connection with a mode of living and is recognized as a 'culture for living', and is more characteristic culture than all metaphysical cultures including architecture, craft, painting, and sculpture. Therefore, it expresses wearer's status or social standing, and furthermore, ideas and values of the times with aesthetic features in their form, color, materials, and pattern, so it is expressed as a mirror reflecting the phases of the times as. Korean costume had been dressed until the period of the Joseon Dynasty without a great change and started to be simplified in a simple style on the grounds of inconvenience in behaviors with the opening of an interchange of Western culture in the civilized period. And, this movement had been continued and Korean costume had been applied as an everyday dress under the name of 'Reformed Korean Costume'. Since the middle phase of 1980s, it aroused many people's interests with the introduction of designs focused on activity and convenience. In 1990's, many people had taken a growing interest in Korean costume with development of various designs keeping pace with the internationalization period and Korean Costume had been revitalized under the name of 'The Modernized Korean Costume'. And, since the 21st century, the advanced communication and full-scaled import of Western fashion have made the introduction of many fashion information in the world into Korea, affected greatly the fashion market, led consumers' sensitivity on a trend to be increased. Therefore, a design accepting a trend 'The Modernized Korean Costume' with fashions has risen. Second, this study is an attempt to suggest a revitalization method of domestic casual Korean costume brands by developing and suggesting competitive and highly value-added products with connection of practicality, variety, and highly sensitive fashion styles. For theoretical study, domestic and foreign literatures, academic journals, professional monthly magazines, and newspapers were examined. And, a process of change and features of the Korean fashion since the civilization period, and concept, features and images of casual Korean costume were analyzed, On the basis of analyzing image, features, and consumers' preference of the modernized Korean costume, a design development plan was established and 10 suits of costume were designed and made.

• Journal of the Korean Magnetics Society
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• v.19 no.3
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• pp.113-119
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• 2009

$^{57}Fe_xCu_{1-x}O$(x = 0.0, 0.02) powders were prepared by sol-gel method and their crystallographic and magnetic hyperfine properties have been studied using X-ray diffraction and $M{\ddot{o}}ssbauer$ spectroscopy (MS). The crystal structure of the samples is found to be monoclinic without any secondary phases and their lattice parameters increase with increasing annealing temperature ($T_A$), which is attributed to an increase in oxygen-vacancy content. MS measurements at room temperature indicate that $Fe^{3+}$ ions substitute $Cu^{2+}$ sites and ferromagnetic phase grow with increasing $T_A$. Magnetic hyperfine and quadrupole interactions of $^{57}Fe_{0.02}Cu_{0.98}O$ ($T_A=500^{\circ}C$) in the antiferromagnetic state at 17 K have been studied, yielding the following results: $H_{hf}=426.94\;kOe$, ${\Delta}E_Q=-3.67\;mm/s$, I.S.=0.32 mm/s, ${\theta}=65^{\circ}$, ${\phi}=0^{\circ}$, and ${\eta}=0.6$.