• Journal of Fisheries and Marine Sciences Education
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• v.18 no.2
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• pp.137-149
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• 2006

The typhoon, heavy rain, blizzard, storm and heavy snowfall had the main caused of natural disasters occurred in Korea from 1993 to 2002. Among them, typhoon has responsible for biggest disaster, recording about 47.4% of total economic damage. Typhoons concentrated mostly in the months from June to October. The average occurrence number in those months ranged from 3.9 to 5.5 based on 30 years of record(1971-2000). However, the numbers increased from 4.0 to 6.2 during the most recent 10 years(1991-2000). Jeju province, among others in Korea, was most frequently affected by typhoon which occurred 23 times during the period of 1991-2000. Typhoons which occurred from July to early August have passed mostly through the west of Jeju, whereas, those of late August to September have passed through the center and eastern sea area of Jeju. The typhoons 'Ramasun' and 'Rusa' caused severe damage in Jeju area in September 2003 and the surge heights were +39cm and +77cm, respectively. The main cause of the damage was surge height which was highly associated with the tidal phase at the time of typhoon passage. The damage caused by typhoon on the aquaculture, fishing boat and harbor cosatline wall around Jeju Island which was amounted to be 417 billion won(\) during the recent 3 years(2002-2004)

• Journal of the Korean housing association
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• v.27 no.4
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• pp.13-22
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• 2016

The long term plan for apartment housing has a important role to make a decision making whether a repair work should be done or not. But, items for repair works are so various that field workers could not understand the context or plan the repair cost and time. These difficulties are drawn from the number of repair items, duplicated application and meaning, new material application and technology time-gap. Therefore, it needs to change or coordinate the repair items to improve the repair condition, reflecting the current material level or repair technologies. In this paper, it aimed at coordination of the repair items through the repair recording sheet which was surveyed in 22 metropolitan areas of Seoul, conducted between 2011 and 2014. The surveyed data are classified into six categories such as building exterior, building interior and so on, according to long term repair plan and the number of data are 1,918. It analyzed the appearing word for repair-concerned and compared the existing items of the long term plan. Items of building exterior are proposed as roof, exterior wall and painting. Building interior has a little meaning to propose the repair items. The water supply facilities are proper to keep the existing repair items. Items of the outdoor facilities could not need a sign board, drainage root and PVC sheath. Through this study, we can coordinate the repair items in apartment and provide the repair item and cost level.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.444-444
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• 2011

Recently, patterned magnetic films and elements attract a wide interest due to their technological potentials in ultrahigh-density magnetic recording and spintronic devices. Among those patterned magnetic structures, magnetic anti-dot patterning induces a strong shape anisotropy in the film, which can control the magnetic properties such as coercivity, permeability, magnetization reversal process, and magneto-resistance. While majority of the previous works have been concentrated on anti-dot arrays with a single magnetic layer, there has been little work on multilayered anti-dot arrays. In this work, we report on study of the magnetic properties of bilayered anti-dot system consisting of upper perforated Co layer of 40 nm and lower continuous Ni layer of 5 nm thick, fabricated by photolithography and wet-etching processes. The magnetic hysteresis (M-H) loops were measured with a superconducting-quantum-interference-device (SQUID) magnetometer (Quantum Design: MPMS). For comparison, investigations on continuous Co thin film and single-layer Co anti-dot arrays were also performed. The magnetic-domain configuration has been measured by using a magnetic force microscope (PSIA: XE-100) equipped with magnetic tips (Nanosensors). An external electromagnet was employed while obtaining the MFM images. The MFM images revealed well-defined periodic domain networks which arise owing to the anisotropies such as magnetic uniaxial anisotropy, configurational anisotropy, etc. The inclusion of holes in a uniform magnetic film and the insertion of a uniform thin Ni layer, drastically affected the coercivity as compared with single Co anti-dot array, without severely affecting the saturation magnetization ($M_s$). The observed changes in the magnetic properties are closely related to the patterning that hinders the domain-wall motion as well as to the magneto-anisotropic bilayer structure.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.10 no.3
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• pp.324-333
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• 1998

Measurements of the local heat transfer coefficients on a hemispherically concave surface with a round oblique impinging jet were made. The liquid crystal transient method was used for these measurements. This method, which is a variation of the transient method, suddenly exposes a preheated wall to an impinging jet while video recording the response of liquid crystal for the surface temperature measurements. The Reynolds number used was 23,000 and the nozzle -to -jet distance was L/d=2, 4, 6, 8 and 10 and the jet angle was $\alpha$=0$^{\circ}$, 15$^{\circ}$, 30$^{\circ}$and 40$^{\circ}$. In the experiment, the maximum Nusselt number at all region occurred at L/d(equation omitted)6 and Nusselt number decreases as the inclined jet angle increases. For the normal jet the contours of constant Nusselt number are circular and as the jet is inclined closer and closer to the surface the contours become elliptical shape. The decreasing rate of the Nusselt number at X/d＞ 0(upstream) on a surface curvature are higher than those on a flate plate and the decreasing rate of the Nusselt number at X/d ＜0(downstream) on a surface curvature are lower than those on a flate plate. And also, the decreasing rate of local Nusselt number distribution at X/d ＜0(upstream) exhibit lower than with X/d ＜0(downstream) as jet angle increases. The second maximum Nusselt number occurred at long distance from stagnation point as jet angle increases.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.11 no.6
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• pp.846-854
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• 1999

Measurements of the local heat transfer coefficients were made on a hemispherically convex surface with a round oblique impinging jet. The liquid crystal transient method was used for these measurements. This method, which is a variation on the transient method, suddenly exposes a preheated wall to an impinging jet while video recording the response of liquid crystal for the surface temperature measurements. The Reynolds number used was 23000 and the nozzle-to-surface distance was L/d=2, 4, 6, 8, and 10 and the jet angle was $\alpha$=$0^{\circ}\; 15^{\circ}\;30^{\circ}C\; and \;40^{\circ}C$. In the experiment, the Nusselt number at the stagnation point decreases as the jet angle increases and has the maximum value for L/d=6. The X-axis Nusselt number distributions exhibit Secondary maxima at $0^{\circ}C\re $\alpha$\re 15^{\circ}C, L/d\le6$ for X/d＜0(upstream) and at $0^{\circ}C\re $\alpha$40^{\circ}C,\;L/d\le4\;and\; at\; 30^{\circ}C\re $\alpha$$\leq$40^{\circ}C,\;L/d\le 6 $for X/d＞0(downstream). The secondary maxima occurs at long distance from the stagnation point as the jet angle increases or the nozzle-to-surface distance decreases. The Y-axis Nusselt number distributions exhibit secondary maxima at Y/d=$\pm$2 for $0^{\circ}C\le a\le30^{\circ}C\; and\; L/d\le4, and \;for\;$\alpha$=40^{\circ}C$and L/d=2. The displacement of the maximum Nusselt number from the stagnation point increases as the jet angle increases or the nozzle-to-surface distance decreases and the maximum distance is about 0.67 times of the nozzle diameter. The ratio of the maximum Nusselt number to the stagnation Nusselt number increases as the jet angle increases.

• The Journal of Korean Medicine
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• v.40 no.1
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• pp.99-113
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• 2019

Objectives: This study is designed to identify the responses of autonomic nervous system and gastrointestinal function which are induced by acupuncture at abdominal anterior cutaneous nerve. Methods: This study is one group before and after pilot study. Subjects were treated once, after having been fasting six hours. They had before tests, labeling points for acupuncture, acupuncture, and after tests in order. The points of acupuncture were motor points of rectus abdominis where the abdominal anterior cutaneous nerve came to the skin from abdominal wall. Before and after tests were consisted of three things: Digital Infrared Thermographic Imaging(D.I.T.I.), Heart Rate Variability(HRV), and Recording of bowel sounds. Results: There were significant differences on the skin temperature of upper body and the frequency of bowel sounds(p<0.001, p<0.001). The HRV parameters and volume of bowel sounds had no significant differences(p>0.05, p>0.05). Conclusion: Even though no significant differences in HRV parameters, the significant differences of skin temperature of upper body and frequency of bowel sounds could mean acupuncture at abdominal anterior cutaneous nerve could affect the autonomic nervous system and gastrointestinal function. However, this study had no group to compare with. Future randomized project should address this issue.

• Fire Science and Engineering
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• v.34 no.2
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• pp.14-21
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• 2020

This paper presents the study of a fire risk to the backside of two miniatures of ISO 9705 2/5 using a lightweight partition for indoor space division and reproduction of the ISO 9705 test. An SGP partition, stud partition, glass wool panel, urethane foam panel, sandwich panel, and glass partition were selected as the test specimens, which are frequently used in construction. According to the ISO 9705 test standard, stabilization was achieved using a measuring device that recorded data before the ignition of a burner and continued recording for 120 s thereafter. After ignition was achieved, the power was increased to 300 kW for 600 s and then reduced to 100 kW for 600 s. The specimens were subsequently observed for 180 s, and the fire risk to the backside and the fire pattern of the wall unit were analyzed. Owing to the amount of heat generated by the ignition source, the maximum temperature of the backside was observed to be 67.7 ℃ for the SGP partition, 55.1 ℃ for the stud partition, 52.4 ℃ for the glass wool panel, 727.4 ℃ for the sandwich panel, 561 ℃ for the urethane foam panel, and 630.5 ℃ for the glass partition. In the cases of the sandwich and urethane foam panels, the explosion of flammable gas occurred by virtue of fusion of the interior materials. The reinforced glass was fractured owing to the temperature difference between the heat- and nonheat-responsive parts. Ultimately, the fire risk to the nearby section room was deemed to be high.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.22 no.2
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• pp.191-205
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• 2000

The purpose of this study was undertaken to determine the effects of orthognathic surgery on speech. The hyposis stated herein is that functional behaviors of the dentofacial complex, such as speech production, may be adversely affected by deviations of a structural nature(especially, Class III malocclusion). Twenty adults with Class III malocclusion(13 female and 7 male) were studied preoperative, immediate postoperative and either 6 or 12 months postoperative lateral cephalograms. They had mandibular prognathism and had undergone mandible setback operation. The position of tongue, soft palate(Uvula), hyoid bone, respiratory track width, and pharyngeal depth were assessed on lateral cephalograms with 23 cephalometric variables, ANOVA, Paired t-tests and Pearson's product-moment correlation coefficient tests were used to evalute the operative changes in all cephalometric parameters. A experienced speech and language pathologists performed narrow phonetic transcriptions of tape-recorded words and sentences produced by each of the ninth patients and the recording tapes were analyzed by phonetic computer program(Computerized Speech Lab(CSL) Model 4300BI(U.S.A.)) These judges also recorded their ratings of each patient's overall consonants, hypernasality, hyponasality, and articulation proficiency. The results obtained are as follows; 1. There were significant changes in distance of posterior pharyngeal wall to tongue (TI-TW2, TS-TW3) after the surgery at 6 months postoperatively(each p<0.01 p<0.05). 2. The posterior tongue point(TI, TS, PPT) moved posteriorly after surgery and remained to its changed position at 6 months postoperatively(p<0.05). The displacement of tongue was correlated with the movement of mandibular setback amount(p<0.05). The hyoid bone moved posteriorly superiorly after immediate postoperative period. There was significant changes in hyoid bone movement after immediated postoperative period(p<0.05), but returned to its original position during the follow-up period(p>0.05) 3. The soft palate was displaced posteriorly superiorly after immediated operative period and remained to its changed position at 6 months postoperatively(p<0.05). ANS-PNS-SPT angle increasing, PPU-PPPo distance narrowing was showed after surgery, and remained its appearance 6 months postoperatively(p<0.05). 4. There were significant changes in formant value and squre diagram of vowel sound after the orthognathic surgery and the follow-up period. There were significant changes in /ㅅ/sound and posterior tongue sound. 5. The posterior movement of tongue and the posteriosuperior movement of soft palate was correlated with mandibular setback amount after orthognathic surgery. On the vowel squre diagram, the author found that the place of articulation after operation moved downward, backward, upward. 6. In assessing speech abnormalities, dental occlusion should be considered as a contributing factor. The vast majority of subjects with preoperative misarticulations eliminated or reduced their errors following orthognathic surgery. There was significant difference in speech impovement between pre- and postoperation.

• Economic and Environmental Geology
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• v.39 no.4 s.179
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• pp.441-450
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• 2006

The on-land seismic survey in Korea was begun in mid-1960s. Kim et al.(1967) of Korea Geological Survey reported on the result of gravity and seismic reflection surveys conducted in the Pohang area for the period of 1963-64 to assess its possibility of oil entrapment. Hyun and Kim (1966) carried out a refraction survey on the tunnel wall. Since then, the KGS geophysicists had conducted seismic surveys on Kyungsang sedimentary basin as a main project for several years. In 1970s, on-land seismic surveys had been conducted for various purposes such as site investigation for the nuclear power plants and industrial complex, exploration for ground water, mineral resources and underground tunnel. The first reflection survey with CMP acquisition was attempted in 1978 by using a digital recording system. But most of on-land seismic surveys had employed the refraction method until 1980s. In 1990s, high resolution reflection and various borehole seismic surveys such as tomography, uphole, downhole, cross-hole methods have been attempted by universities and engineering companies. The applications of on-land seismic surveys have been enlarged for both academic and industrial purposes such as investigation of geologic structure of the fault and tidal flat area, construction of highway, railroad and dam, geothermal energy and mineral resource exploration, environmental assessment for waste disposal sites and archaeological investigations. In 2002, the first crustal seismic survey was carried out on the profile of 294km length across the whole peninsular. It is expected that the advanced technology and experience acquired through offshore seismic surveys, which have been conducted in continental shelf of Korea and foreign oil fields, will stimulate the more active on-land seismic explorations.

• The Korean Journal of Physiology
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• v.4 no.1
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• pp.59-67
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• 1970

In recent observations on vestibular eye movements in mammals, reported by several different workers, it was indicated that the pattern of reflex eye movement from semicircular canal nerve stimulation in rabbits was different from that observed in the other species such as cats and dogs. Observing the different anatomical features of the extraocular muscles of rabbits, Kim ascribed the different pattern of eye movement of rabbits to the functional difference of inferior and superior oblique muscles from those of other species. Present experiment was carried out to elucidate a physiological mechanism underlying in such particular pattern of reflex eye movement in rabbits. An individual canal nerve was selectively stimulated, under a dissecting microscope, by a fine electrode induced into an ampulla through a hole provided on the wall of corresponding osseous canal, and responses of the extraocular muscles were checked by recording the isotonic changes of muscle length. Following results were obtained. 1. Direct stimulation of the superior or inferior oblique muscles Produced upward or downward movement of the eye turning toward medial side respectively. 2. Stimulation of the unilateral canal nerve Produced a marked contraction of a main contracting ocular muscle and simultaneous relaxation of an antagonistic muscle in both eyes. Less potent contraction of an additional ocular muscle was observed and it appeared to augment the function of the main contracting muscle in the ipsilateral eye. 3. Stimulation of superior semicircular canal nerve caused a primary contraction of superior rectus, synergic contraction of superior oblique and relaxation of inferior rectus in ipsilateral eye. Contraction of inferior oblique and relaxation of superior oblique were observed in the contralateral eye. 4. Stimulation of lateral semicircular canal nerve produced a primary contraction of medial rectus, synergic contraction of superior oblique and relaxation of lateral rectus in the ipsilateral eye. Contraction of lateral rectus and relaxation of medial rectus were observed in the contralateral eye. 5. Stimulation of inferior semicircular canal nerve produced a primary contraction of superior oblique, synergic contraction of superior rectus and relaxation of inferior oblique in the ipsilateral eye. Contraction of. inferior rectus and relaxation of superior rectus were observed in the contralateral eye. 6. Upon stimulation of individual canal nerve, the pattern of eye movement in rabbits is different from those of cats, however, the responses of the extraocular muscles appear to be similar in two species. Therefore, it is concluded that the different Pattern of eye movement in both species are not due to the possible difference of vestibule-ocular reflex pathways but to the functional difference of superior and inferior oblique muslces.