• Journal of the Korean earth science society
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• v.21 no.1
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• pp.59-66
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• 2000

In Kyeongsang basin, there were very dynamic magmatic activities, resulting to form volcanic and plutonic rocks. A plutonic recycle appeared in this region. Presumption of the pressure for hornblende-bearing granitic rock among the plutonic rocks, can support important informations for the emplacement depth of Cretaceous Bulgugsa granites in Kyeongsang basin. $Al^T$(Al total) contents of hornblende is related to the pressure, oxygen fugacity, and compositions of other minerals having the solid solution. So we apply the $Al^T$ content of hornblende to several empirical and experimental geobarometer systems to presume the pressure and to determine the emplacement depth of Cretaceous Bulgugsa granites in Kyeongsang basin from the inferred pressure. With the result that we applied the $Al^T$ contents of hornblende to the various geobarometers, there was a positive relationship between the pressure and $Al^T$. The minimum pressure value ranges from 0.73 to 1.70kbar in Kyeongju and the maximum value from 2.02 to 3.16kbar in Kimhae. And then the tectonic setting in Kyeongsang basin has no relation to the emplacement depth of Cretaceous granites and means variations with the movement of vertical component in each area. As we suppose that the density of earth's crust is $2.8g/cm^3$, the average values of the emplacement depth ranges in each area range from 2.6 to 11.4km. These data confirm the previous idea about the emplacement depth of Cretaceous granites in Kyeongsang basin, and these geobarometers using the $Al^T$ contents of hornblende is available though they have much limits. Therefore Cretaceous Bulgugsa granites in Kyeongsang basin was the shallow depth intrusive rut and the exposed granites was the shallow depth crust.

• Journal of the Korean Institute of Landscape Architecture
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• v.38 no.2
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• pp.1-8
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• 2010

The purpose of the study was to evaluate the influence of landscaping pavements on WBGT(Wet-Bulb Globe Temperature) of outdoor spaces that lack ventilation and shade at summer midday. The relative humidity(RH), dry-bulb temperature(DT) and globe temperature(GT) were recorded every minute from June to October 2009 at a height of 1.2m above ten experimental beds with different pavements, by a measuring system consisting of an electric humidity sensor(GHM-15), resistance temperature detector(RTD, Pt-100), standard black globe(${\phi} 150mm$) and data acquisition systems(National Instrument's Labview and Compact FieldPoint). Additionally, the surface dry-bulb temperatures also were recorded and compared. The area of each experimental bed was 1.5m(W)${\times}$2.0m(L) and ten different kinds of pavement were used including grass, grass+cubic stone, grass+porous brick, brick, stone panels, cubic stone, interlocking blocks, clay brick, naked soil, gravel and concrete. To prevent interference from ventilation, a 1.5m height cubic steel frame was established around each bed and each vertical side of the frame was covered with transparent polyethylene film. Based on the records of the hottest period from noon to 3 PM on 26 days with a peak dry-bulb temperature over $30^{\circ}C$ at natural condition, the wet-bulb temperature(WT) and WBGT were calculated and compared. The major findings were as follows: 1. The average surface DT was $40.1^{\circ}C$, which is $9^{\circ}C$ higher than that of the natural condition. The surface DT of the pavements with grass were higher than those of concrete and interlocking block. The peak DT of the surface almost every pavement rose to above $50^{\circ}C$ during the hottest time. 2. The averages of DT, WT and GT were $40.1^{\circ}C$, $27.5^{\circ}C$ and $49.1^{\circ}C$, and the peak values rose to $48.1^{\circ}C$, $45.8^{\circ}C$ and $59.5^{\circ}C$, respectively. In spite of slight differences that resulted according to pavements, no coherent differentiating factor could be found. 3. The average WBGT of grass was the highest at $34.3^{\circ}C$ while the others were similar in the range of around $33{\pm}1^{\circ}C$. Meanwhile, the peak WBGT was highest with stone panel at $47.9^{\circ}C$. Though there were some differences according to pavements, and while grass seemed to be worst in terms of WBGT, it seems difficult to say ablolutely that grass was the worst because the measurement was conducted without ventilation and shade during summer daytime hours only, which had temperatures that rose to a dangerous degree(above $45^{\circ}C$ WBGT), withering the grass during the hottest period. The average WBGT resulted also showed that the thermal environment of the pavement without ventilation and shade were at an intolerable level for humans regardless of the pavement type. In summary, the results of this study show that ventilation and shade are more important factor than pavement type in terms of outdoor thermal comfort in summer daylight hours.

• Clinical and Experimental Pediatrics
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• v.49 no.12
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• pp.1308-1314
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• 2006

Purpose : This study aimed to evaluate the usefulness of auditory evoked potential (AEP) in clarifying neuronal development in premature small for gestational age (SGA), and appropriate for gestational age (AGA) infants. Methods : A total of 183 premature infants who were born from August 2002 to July 2005, were examined with AEP. They were divided into three groups; AGA, symmetric-SGA and asymmetric-SGA group. Results : Statistically significant differences in the head circumference were observed in three groups. Among the risk factors, prevalence of hypoglycemia and hypoalbuminemia between AGA and asymmetric SGA infants were significantly different. V absolute peak latency (APL) in the right side of AGA infants was delayed were than that of asymmetric SGA infants. III-V interpeak latency (IPL) of asymmetric SGA infants was delayed more than that of symmetric SGA infants. Moreover, I-V IPL on both sides of symmetric SGA infants was shortened more than that of AGA infants. However, all the results of AEP were within the reference range, according to gestational age. Birth weight of, only asymmetric SGA, was related to the III APL on both sides and the III-V IPL on right side. Conclusion : This study shows that the values of APL and IPL of premature SGA infants are different than that of premature AGA infants. These data could be an indicator in evaluating the neurologic functions of small for gestational age infants.

• Clinical and Experimental Pediatrics
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• v.52 no.8
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• pp.869-874
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• 2009

Purpose : Short attacks of headache are present in the pediatric age group. Short-lasting headaches (SLH) have been infrequently reported in children and adolescents. This study aims to assess the prevalence, clinical characteristics, treatment, and prognosis of short-lasting headaches in children and adolescents. Methods : One hundred twenty-three consecutive patients attended the Chosun University Hospital Headache Center between March 2006 and July 2007. Among 123 headache patients, 44 patients with one key criterion, namely, recurrent headaches episodes of a few seconds to less than 30 minutes, were selected. Results : Of the 123 headache patients, 44 (35.8%, males 18, females 26) had SLH. The mean age was 9.24 years (range 2.3-14.2). The mean headache frequency was $11.50{\pm}10.30$ per month, mean severity was $4.86{\pm}1.36$ out of 10, and the mean PedMIDAS score was $7.97{\pm}17.51$. SLH was significantly more common in children <6 years old (10/22, 45.5%) than in ${\geq}6$ years old (34/101, 33.7%) (P=0.015). The nature of pain was pressure in 30.2%, stabbing in 27.9%, throbbing in 18.6%, and dull in 11.7%. In 52.4% patients, the pain occurred in the front, one side of the temple in 28.5%, both sides of the temple in 7.1%, and back in 4.8% patients. The duration of attacks was <6 minutes in 38% and ${\geq}6$ minutes in 61.4%. The intensity of the pain was 4-6 out of 10 in 75.0%, in 13.6% 1-3, and in 11.4% 7-10. Treatment was significantly effective in reducing the frequency, duration, and severity of headaches and the PedMIDAS score after 3 months (P<0.05). Conclusion : Short attacks of headache are common (35.8%) in children and adolescents. These are difficult to classify according to International Headache Society criteria. The outcome, after a period of 3 months to 2 years, was favorable in most patients. Further studies are needed to gather more data and to obtain a better description of these forms of headache in the pediatric group.

• Korean Journal of Remote Sensing
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• v.34 no.2_1
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• pp.237-248
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• 2018

The vertical distribution of hydrometeor before precipitation near the cloud base has been analyzed using a scanning lidar, rawinsonde data, and Cloud-Resolving Storm Simulator (CReSS). This study mostly focuses on 13 Desember 2016 only. The typical synoptic pattern of lake-effect snowstorm induced easterly in the Yeongdong region. Clouds generated due to high temperature difference between 850 hPa and sea surface (SST) penentrated in the Yeongdong region along with northerly and northeasterly, which eventually resulted precipitation. The cloud base height before the precipitation changed from 750 m to 1,280 m, which was in agreement with that from ceilometer at Sokcho. However, ceilometer tended to detect the cloud base 50 m ~ 100 m below strong signal of lidar backscattering coefficient. As a result, the depolarization ratio increased vertically while the backscattering coefficient decreased about 1,010 m~1,200 m above the ground. Lidar signal might be interpreted to be attenuated with the penetration depth of the cloud layer with of nonspherical hydrometeor (snow, ice cloud). An increase in backscattering signal and a decrease in depolarization ratio occured in the layer of 800 to 1,010 m, probably being associated with an increase in non-spherical particles. There seemed to be a shallow liquid layer with a low depolarization ratio (<0.1) in the layer of 850~900 m. As the altitude increases in the 680 m~850 m, the backscattering coefficient and depolarization ratio increase at the same time. In this range of height, the maximum value (0.6) is displayed. Such a result can be inferred that the nonspherical hydrometeor are distributed by a low density. At this time, the depolarization ratio and the backscattering coefficient did not increase under observed melting layer of 680 m. The lidar has a disadvantage that it is difficult for its beam to penetrate deep into clouds due to attenuation problem. However it is promising to distinguish hydrometeor morphology by utilizing the depolarization ratio and the backscattering coefficient, since its vertical high resolution (2.5 m) enable us to analyze detailed cloud microphysics. It would contribute to understanding cloud microphysics of cold clouds and snowfall when remote sensings including lidar, radar, and in-situ measurements could be timely utilized altogether.

• Progress in Medical Physics
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• v.9 no.3
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• pp.127-136
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• 1998

On-line geometrical quality assurance system has been developed using electronic portal imaging system(OQuE). EPID system is networked into Pentium PC in order to transmit the acquisited images to analysis PC. Geometrical QA parameters, including light-radiation field congruence, collimator rotation axis, and gantry rotation axis can be easily analyzed with the help of graphic user interface(GUI) software. Equipped with the EPID (Portal Vision, Varian, USA), geometrical quality assurance of a linear accelerator (CL/2100/CD, Varian, USA), which is networked into OQuE, was performed to evaluate this system. Light-radiation field congruence tests by center of gravity analysis shows 0.2～0.3mm differences for various field sizes. Collimator (or Gantry) rotation axis for various angles could be obtained by superposing 4 shots of angles. The radius of collimator rotation axis is measured to 0.2mm for upper jaw collimator, and 0.1mm for lower jaw. Acquisited images for various gantry angles were rotated according to the gantry angle and actual center of image point obtained from collimator axis test. The rotated images are superpositioned and analyzed as the same method as collimator rotation axis. The radius of gantry rotation axis is calculated 0.3mm for anterior/posterior direction (gantry 0$^{\circ}$ and 170$^{\circ}$) and 0.7mm for right/left direction(gantry 90$^{\circ}$ and 260$^{\circ}$). Image acquisition for data analysis is faster than conventional method and the results turn out to be excellent for the development goal and accurate within a milimeter range. The OQuE system is proven to be a good tool for the geometrical quality assurance of linear accelerator using EPID.

• Journal of the Korean Society of Groundwater Environment
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• v.6 no.4
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• pp.194-205
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• 1999

Hydrogeochemical variation and environmental isotope at the some abandoned metal mine (Sanggok, Keumsil, Jangpung and Samdeok) creeks of the Hwanggangri mining district were carried out based upon the physicochemical properties for surface water collected of February in 1998. Hydrogeochemical composition of the all water samples are characterized by the relatively significant enrichment of Ca$^{2}$, alkaline ions, N $O_3$$^{－}$ and Cl$^{－}$ in normal surface water, whereas the surface waters near the mining area are relatively enriched in Ca$^{2+$, Mg$^{2＋}$, heavy metals. HC $O_3$$^{－}$ and S $O_4$$^{2－}$. Surface waters of the mining creek have low pH, high EC and extremely high concentrations of TDS compared with surface water of the non-mining creeks. The range of $\delta$D and $\delta$$^{18}$O values (SMOW) in the waters are shown in －65.0 to－71.2$\textperthousand$ and －9.1 to－10.2$\textperthousand$. The d($\delta$D－$\delta$$^{18}$O) value with those of water samples ranged from 7.3 to 10.9. These $\delta$D and $\delta$$^{18/}$ of the acid mine water are more heavy values than those of surface water. The values have revealed the positive correlation between isotopic compositions and major elements, because those $\delta$D and $\delta$$^{18}$O values increase with increasing TDS. HC $O_3$$^{－}$ , S $O_4$$^{2－}$ and Ca$^{2＋}$ concentration. Using WATEQ4F, saturation index of albite calcite, dolomite and mostly clay minerals in water of the mining area show undersaturated and progressively evolved toward the equilibrium condition due to fresh water mixing, however, surface waters of the non-mining area are nearly saturated and/or supersaturated. Geochemical modeling showed that mostly toxic heavy metals within water in the mining creek may exist largely in the from of metal-sulfate (MS $O_4$$^{2－}$), free metal (M$^{2＋}$/), C $O_3$$^{－}$ and/or OH$^{－}$ complex ions. Based on the geology, water chemistry and environmental istopic data the water compositions from the Sanggok and Keumsil mine creek (consist mainly of Cambro-Ordovician carbonate rocks of the Cho-seon Supergroup) show higher PH, Ca$^{2＋}$, Mg$^{2＋}$ , HC $O_3$$^{－}$ and more heavy $\delta$D and $\delta$$^{18}$O values than those from the Jangpung and Samdeok mine creek (consist of age -unknown metasedimentary rocks of the Ogcheon Supergroup and/or Jurassic grani-toids), but each of these waters represents a similar hydrogeochemical evolution path by the mine water mixing.

• Journal of Chest Surgery
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• v.32 no.8
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• pp.715-721
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• 1999

Background:The number of old patients receiving coronary artery bypass grafting(CABG) is increasing. With the more recent advances in operative techniques, the age at which CABG is indicated has also increased. This study evaluated the risk factors associated with the hospital mortality and the morbidity following CABG in elderly patients. Material and Method: Between March 1991 and June 1998, we retrospectively reviewed 45 consecutive patients aged 65 years or older who underwent CABG. We compared the data with the results of 179 patients under the age 65 years operated during the same period. Result: Mean age was 68${\pm}$1.41 years(range 65 to 74 years). Emergency surgery was required in 4, and elective surgery in 41 patients. The mean number of distal anastomosis per patient was 3.62 ${\pm}$0.81 and mean aortic cross-cramp time was 69.84${\pm}$18.5 minutes. Thirty patients had Canadian class III or IV preoperatively, but 43 patients had class I or II postoperatively. The left ventricular ejection fraction increased significantly from 54.23${\pm}$10.62% preoperatively to 58.14${\pm}$9.88% postoperatively(p<0.05). Postoperative complication was pneumonia in 2 patients, acute renal failure in 2 patients, sternal wound infection in 1 patient, and postoperative myocardial infarction in 1 patient. There were two postoperative deaths. The causes of deaths were low output syndrome in one patient, and sepsis due to pneumonia in the other patient. The hospital mortality was higher in the elderly group(4.4 versus 2.86%) but was not statistically significant(p>0.05). Incremental risk factors for hospital deaths in the elderly were emergent operation, preoperative PTCA, postoperative use of IABP and postoperative ARF(p<0.05). The duration of hospital stay after operation was significantly longer for the elderly group than the younger group(19.27${\pm}$12.51 vs 15.55${\pm}$6.99 days; p＜ 0.05). Follow-up was complete for 34 of the hospital survivors and ranged from 1 to 73 months(mean: 23.58${\pm}$19.56 months). There was no late mortality of cardiac origin. Conclusion: Age is an important factor in selecting optimal management for elderly patients with coronary compromise, but age alone should not dictate the choice of therapy. Coronary artery bypass surgery in the elderly is associated with acceptable early mortality and excellent long-term results.

• Journal of Chest Surgery
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• v.29 no.7
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• pp.769-776
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• 1996

The application of video-assisted thoracic surgery (VATS) in the examination of the thoracic cavity can be a new option in patients with mediastinal tumor because it provides outstanding visibility of the structures of the mediastinum. By clear viewing through the thoracoscope, a mediastinal tumor can be biopsied or resected, depending on the findings during an operation. We reviewed all patients who underwent curative or diagnostic operations from March 1990 to August 1995 under the impression of a mediastinal mass. The total number of patients were 113 with 59 males and 54 females. Group A underwent resection of tu or by thoracotomy(38 patients: 18 males, 20 females), and group B underwent resection of tumor by VATS (36 patients : 20 males and 16 females). Seven patients in group B were excluded because they underwent thoracotomy due to pleural adhesion or intra-operative bleeding ; therefore, the true VATS group numbered 29 cases. Group C underwent Iymph node biopsy by VATS(33 patients'16 males, 17 females), and group D(6 patients: 5 males, 1 female) underwent Iymph node biopsy through anterior mediastinotomy. The mean age in group A was 36.2 years compared to 41.3 years In group B. We compared operation time, frequency of injection for pain control, duration of chest tube insertion, postoperative hospital stay, and diagnostic yield. In group A, they were 164 minutes, 3.4 times, 5.2 days, and 11.3 days, respectively, in comparison to 152 minutes, 2 times, 4.7 days, and 8.3 days, respectively, in group B. These data revealed that the day of discharge was significantly shorter in group B (p valu : 0.03). In group C, the mean age was 45.8 years (range 1 ∼70). The operation time was from 30 to 335 minutes (mean 105), pain control was required from 0 to 15 times(mean 3.2), and a chest tube was needed for 1 to 36 days (mean 6.1). In group D, mean age was 53.3 years, operation time 121 minutes, pall control injec- tion frequency 2.6 times, and mean chest tube duration 10.5 days. The diagnostic yield in group C was 8 oyo compared to 100 oyo in group D although the number of patients in group D is small.

• Journal of Chest Surgery
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• v.42 no.2
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• pp.238-243
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• 2009

Background: Radiofrequency obliteration and endovenous laser therapy of the greater saphenous vein have recently been introduced as alternative, minimally invasive techniques for the treatment of saphenous vein incompetence. The 7 Fr. VNUS $ClosureFAST^{(R)}$ radiofrequency obliteration system was introduced in Gwang-Ju Veterans hospital. The purpose of this study is to evaluate the efficacy and complications of radiofrequency obliteration using the 7 Fr. VNUS $ClosureFAST^{(R)}$ system. Material and Method: Between May 2, 2007 and May 31, 2008, we performed radiofrequency obliteration on 90 patients. The number of males was 67 and their mean age was $57.9{\pm}11.0$ (range: $23{\sim}78$) years old. The patients underwent follow up exams at 3 weeks after the procedures and then every 3 months. The effects of treatment and the complications were reviewed. Result: The postoperative complications were ecchymosis (94.4%), pain (27.8%), paresthesia (25.6%), bullous formation (8.9%), edema (6.7%) and phlebitis (2.2%). One patient showed good blood flow after 3 weeks and one patient showed good blood flow after 3 months. The one-year success rate of radiofrequency obliteration in varicose veins was 97.6%. Conclusion: Our data showed acceptable operative results and short-term clinical results for treating varicose veins with radio frequency obliteration. Long-term follow-up and comparison of radio frequency obliteration with high ligation and stripping, previous radiofrequency ablation and endovenous laser therapy are needed in the future.