• Atmosphere
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• v.24 no.1
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• pp.1-15
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• 2014

This study compared ensemble mean and probability forecasts of snow depth amount associated with winter storm over South Korea on 28 December 2012 at five operational forecast centers (CMA, ECMWF, NCEP, KMA, and UMKO). And cause of difference in predicted snow depth at each Ensemble Prediction System (EPS) was investigated by using THe Observing system Research and Predictability EXperiment (THORPEX) Interactive Grand Global Ensemble (TIGGE) data. This snowfall event occurred due to low pressure passing through South Sea of Korea. Amount of 6 hr accumulated snow depth was more than 10 cm over southern region of South Korea In this case study, ECMWF showed best prediction skill for the spatio-temporal distribution of snow depth. At first, ECMWF EPS has been consistently enhancing the indications present in ensemble mean snow depth forecasts from 7-day lead time. Secondly, its ensemble probabilities in excess of 2~5 cm/6 hour have been coincided with observation frequencies. And this snowfall case could be predicted from 5-day lead time by using 10-day lag ensemble mean 6 hr accumulated snow depth distribution. In addition, the cause of good performances at ECMWF EPS in predicted snow depth amounts was due to outstanding prediction ability of forming inversion layer with below $0^{\circ}C$ temperature in low level (below 850 hPa) according to $35^{\circ}N$ at 1-day lead time.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.29 no.5 s.236
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• pp.643-652
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• 2005

Saturated nucleate pool boiling experiments for binary mixtures, which are consisted of refrigerant R11 and R113, were performed with constant wall temperature condition. Results for binary mixtures were also compared with pure fluids. A microscale heater array and Wheatstone bridge circuits were used to maintain the constant temperature of the heating surface and to obtain heat flow rate measurements with high temporal and spatial resolutions. Bubble growth images were captured using a high speed CCD camera synchronized with the heat flow rate measurements. The departure time for binary mixtures was longer than that for pure fluids, and binary mixtures had a higher onset of nucleate boiling (ONB) temperature than pure fluids. In the asymptotic growth region, the bubble growth rate was proportional to a value between $t^{\frac{1}{6}}$ and $t^{\frac{1}{4}}$. The bubble growth behavior was analyzed to permit comparisons with binary mixtures and pure fluids at the same scale using dimensionless parameters. There was no discernable difference in the bubble growth behavior between binary mixtures and pure fluids for a given ONB temperature. And the departure radius and time were well predicted within a ${\pm}30{\%}$ error. The minimum heat transfer coefficient of binary mixtures occurred near the maximum ${\mid}y-x{\mid}$ value, and the average required heat flux during bubble growth did not depend on the mass fraction of R11 as more volatile component in binary mixtures. Finally, the results showed that for binary mixtures, a higher ONB temperature had the greatest effect on reducing the heat transfer coefficient.

• Korean Journal of Ecology and Environment
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• v.46 no.2
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• pp.205-214
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• 2013

In Yeongsan River estuary, located in the southern West Coast, a dike was constructed in December 1981. After the construction of a dike, discharge mechanism of fresh water has been changed, the water quality and chlorophyll-a are expected to be influenced by fresh water discharge. We investigated temporal and spatial variations and long-term trend of phytoplankton biomass (chlorophyll-a) and environmental factors. The concentrations of nutrient and chlorophyll-a were generally high in summer and the concentrations were increased toward downstream. Surface/bottom salinity difference was negatively correlated with salinity in surface water but positively with nutrient and chlorophyll-a. TN, TP and DIN concentrations were generally increased over 10 years. This study can provide information for better management of water quality for Youngsan River estuary.

• Journal of the Society of Naval Architects of Korea
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• v.38 no.1
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• pp.1-8
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• 2001

The computations of the turbulent flow around the ship models with the free-surface effects were carried out. Incompressible Reynolds-Averaged Navier-Stokes equations were solved by using an explicit finite-difference method with the nonstaggered grid system. The method employed second-order finite differences for the spatial discretization and a four-stage Runge-Kutta scheme for the temporal integration. For the turbulence closure, a modified Baldwin-Lomax model was exploited. The location of the free surface was determined by solving the equation of the kinematic free-surface condition using the Lax-Wendroff scheme and a free-surface conforming grid was generated at each time step so that one of the grid boundary surfaces always coincides with the free surface. An inviscid approximation of the dynamic free-surface boundary condition was applied as the boundary conditions for the velocity and pressure on the free surface. To validate the computational method developed in the present study, the computations were carried out for beth Wigley and Series 60 $C_B=0.6$ ship model and the computational results showed good agreements with the experimental data.

• Economic and Environmental Geology
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• v.29 no.5
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• pp.561-573
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• 1996

The igneous rocks in the Goseong area, the southwestern part of the Gyeongsang basin, are composed of the volcanic rocks, Bulgugsa granites and intrusive andesites. The volcanic rocks are andesitic lapilli tuff, dacite and rhyolite. The granites are mainly of hornblende-biotite granite and intruded into the sedimentary basement and the volcanic rocks. The intrusion of andesitic dyke is thought to be the latest igneous activity in the area. In the variation diagrams of the major oxides, the three igneous rock types show different variational trends, indicating that they were from the different magmatic pulses. K-Ar radiometric ages suggest that the igneous activity in the Goseong area had occurred during late Cretaceous period. The ages of the volcanic rocks seem likely to have become younger due to the thermal effect by the granitic intrusion. The major element compositoinal variation of the granites from the Goseong area are compared with those from the Jindong, Geoje and Masan areas. By the comparison, it is easily understood that the Jindong granites are fairly different from the other three granites. On the other hand, the Goseong, Geoje and Masan granites generally show similar variational trends with each other, suggesting that they are of similar genetic origin. Combining the similarity of the geochemical features and the difference of the intruding ages between the Goseong and Masan granites, it seems like that the magma generation from the same source materials had occurred at a temporal interval.

• Korean Journal of Environmental Biology
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• v.22 no.1
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• pp.43-56
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• 2004

The seasonal distribution pattern of zooplankton were studied on the basis of the zooplankton samples collected from 9 stations in Jinhae Bay in May, August, November and February, 2001 to 2002. A total of 31 species in 37 taxa was occurred in Jinhae Bay. Copepods were pyedominant through fall to spring and cladecerans in summer. There aye high spatio-temporal fluctuations in the zooplankton abundance in a range of 27 to 28,221 indiv. $m^{-3}$. Of these, an neritic species, Acartia omorri and Oentropages abdominals were predominent in february; Palaealanus parvus s. 1 in November; Penilia avirostris in August. Species diversity was low in the northwestern regims where anoxia layer is occurred in summer, while in the other seasons there was no a great difference between stations. It indicates that the distribution pattern of zooplankton may be seasonally strongly affected by a mechanism of hypoxia formation in Jinhae Bay.

• The Journal of Korean Physical Therapy
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• v.21 no.3
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• pp.95-102
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• 2009

Purpose: This study evaluates MCP-1 expression in the dorsal horn of a rat model of lumbar disc herniation by an autograft of the nucleus pulposus to the spinal nerve. Methods: After a coccygeal nucleus pulposus graft to the left $5^{th}$ lumbar spinal nerve, proximal to dorsal root ganglion, mechanical allodynia and thermal hyperalgesia were assessed 1 day before surgery, and 1, 10, 20, 30 days after surgery. The mRNA of MCP-1 in the dorsal horn was assessed by real time PCR to compare the temporal pattern of neuropathic pain of the lumbar disc herniation model. Results: In the ipsilateral side of the lumbar disc herniation models, mechanical allodynia and thermal hyperalgesia reached a maximum at 10 days after surgery with significant difference from the control group. Pain was also provoked in the contralateral side of the lumbar disc herniation models with less intensity than the ipsilateral side. The level of MCP-1 mRNA expression in the dorsal horn reached a peak at 20 days after surgery. Conclusion: Mechanical allodynia and thermal hyperalgesia was induced by nucleus pulposus in a rat lumbar disc herniation model, similar to a previously reported peripheral nerve injury model. The level of MCP-1 expression was higher in the dorsal horn of the ipsilateral and contralateral sides. These results suggest that MCP-1 might play a role in the maintenance of neuropathic pain.

• Journal of the Korean Society of Physical Medicine
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• v.8 no.1
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• pp.49-58
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• 2013

PURPOSE: The purpose of this study was to determine if auditory cues velocity has a greater effect on the gait pattern of patients with Parkinson's disease (PD) than the cues applied individually. METHODS: The subjects were 15 elderly patients diagnosed with PD, 15 healthy elderly persons. Patients were measured of three conditions performed in random order: slow, general, fast. The auditory cue velocity consisted of a metronome beat ${\pm}20%$ than the subject's general gait speed. Using a motion analysis and a force platform measurement system, changes in spatiotemporal variables, kinetic and kinematic variables were compared to gait analysis. RESULTS: Comparison between the auditory cues velocity, there was a significant difference in the spatiotemporal variables with regard to the cadence, stride length, support time, step length, double support time (p<.05). Comparison between the auditory cues velocity, there was a significant increase general and fast velocity gait than slow velocity gait in the maximum flexion in swing phase of knee joint (p<.05). There appears to be the aspect of an increasing ground reaction force (GRF) on the first peak in the vertical axis (p<.05). CONCLUSION: Auditory cues velocity improved of spatio-temporal factors, kinematic and kinetic factors depending on the velocity of the faster. Therefore at the rehabilitation training of PD patients auditory cues velocity would be used for recovery and gait reeducation, may arise through the patients functional ability.

• Korean Journal of Applied Biomechanics
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• v.21 no.5
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• pp.653-660
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• 2011

The purpose of this study was to compare selected kinematic variables between male medalists and a Korean male javelin thrower at the IAAF World Championships, Daegu 2011. The three medalists and one Korean javelin thrower that participated in the Championships were videotaped using three high-speed cameras (300 frames/s, EX-F1 Exilim, Casio, Japan). The results showed that the release and attitude angles of the Korean male javelin thrower (KMJT) were greater than that of the medalists, whereas the attack angle of the KMJT was smaller than that of the medalists. This study also found that the KMJT clearly had a lower release height than the medalists. As a possible adaptation of his physique to the skill, the KMJT used a small trunk inclination angle and produced greater inclination angles at his upper extremities. These results may be linked to an increase in the release angle of the KMJT. There were some difference between the KMJT and the medalists in terms of the length and duration of the delivery phase. In harmony with the shorter length of the delivery phase, its duration was shorter for the KMJT in comparison to the medalists. Because the delivery stride is considered to be a primary generator of endpoint speed, this decrease in the delivery phase time would decrease the javelin velocity at release. The amount of time taken in the delivery phase may be a critical factor to enhance a javelin thrower's performance. Thus, rhythmic movement training specifically designed for the KMJT will help him attain an optimal throwing position.

• Journal of architectural history
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• v.13 no.3
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• pp.97-117
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• 2004

The tradition of architecture in the East and the West are different in many ways. One of the basic cause of such difference, however, is the different ways of perception of space and time. This paper aims to identify the attitude of perception of space and time in the cultures of the East and the West, and its influence on architecture. Degrees of importance placed on either space or time, as well as the modes of perception of space and time are discussed in relation to architecture. Basically, the architecture of the West seems to be more spatially oriented than the East, and this have much to do with the fact that the tradition of Western architecture is visually oriented. On the other hand, East Asian architecture have been more conscious on bodily feeling and its movement in architecture. Spatial units of traditional Eastern architecture, are arranged in such a way in which man can experience the change of space that is supposed to be organized to form a sequential message. Thus, in the East, temporal dimension is more deliberately included in the course of architectural experience compared to the cases of the West. Although it is not easy to attempt any kind of value judgment on such aspects, it is necessary to understand how the different perception of space and time influenced architectural outcome, especially when one wants to understand the cultural cause that have made the architectures of the East and the West very different. Such understanding is particularly important in East Asia where their future of architecture depends much on how they harmonize the Eastern and Western background which are already built up as two cultural structure in their consciousness to be able to create more desirable architecture for themselves.