• Journal of Korean Neurosurgical Society
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• v.45 no.4
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• pp.213-218
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• 2009

Objective : This study is a retrospective clinical study over more than 4 years of follow up to understand the mechanism of load sharing across the graft-bone interface in the static locking plate (SLP) fixation compared with non-locking plate (NLP). Methods : Orion locking plates and Top non-locking plates were used for SLP fixation in 29 patients and NLP fixation in 24 patients, respectively. Successful interbody fusion was estimated by dynamic X-ray films. The checking parameters were as follows : screw angle (SA) between upper and lower screw, anterior and posterior height of fusion segment between upper and lower endplate (AH & PH), and upper and lower distance from vertebral endplate to the end of plate (UD & LD). Each follow-up value of AH and PH were compared to initial values. Contributions of upper and lower collapse to whole segment collapse were estimated. Results : Successful intervertebral bone fusion rate was 100% in the SLP group and 92% in the NLP group. The follow-up mean value of SA in SLP group was not significantly changed compared with initial value, but follow-up mean value of SA in NLP group decreased more than those in SLP group (p=0.0067). Statistical analysis did not show a significant difference in the change in AH and PH between SLP and NLP groups (p>0.05). Follow-up AH of NLP group showed more collapse than PH of same group (p=0.04). The upper portion of the vertebral body collapsed more than the lower portion in the SLP fixation (p=0.00058). Conclusion : The fused segments with SLP had successful bone fusion without change in initial screw angle, which was not observed in NLP fixation. It suggests that there was enough load sharing across bone-graft interface in SLP fixation.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.9 no.3
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• pp.111-118
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• 2004

An ocean buoy was deployed 10 km off Donghae city, Korea at a depth of 130 m to measure meteorological (air pressure, air temperature, wind speed, wind gust, wind direction, relative humidity) and oceanographic data (water properties and currents in the whole column) in real-time. The buoy recorded a maximum wind gust of 25 m/s (10 minutes' average speed of 20 m/s) and a minimum air pressure of 980 hPa when the eye of typhoon Maemi passed by near the Uljin city, Korea at 03:00 on 13 September 2003. The wave height reached maximum of 9 m with the significant wave height of 4 m at 04:00 (1 hour after the passage of Maemi). The currents measured near the surface reached up to about 100 cm/s at 13:00 (10 hours after the passage of Maemi). The mixed layer (high temperature and low salinity) thickness, which was accompanied by strong southward current, gradually increased from 20 m to 40 m during the 10 hours. A simple two layer model for the response to an impulsive alongshore wind over an uniformly sloping bottom developed by Csanady (1984) showed reasonable estimates of alongshore and offshore currents and interface displacement for the condition of typhoon Maemi at the buoy position (x=8.15 km) during the 10 hours.

• Journal of Chest Surgery
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• v.29 no.10
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• pp.1143-1147
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• 1996

Video-assisted thoracic surgery(VATS) is emerging as a potentially less invasive means of managing a wide variety of thoracic disorders. VATS was performed in 46 cases, in the Department of Thoracic & Cardiovascular Surgery of Chonbuk national University Hospital from August 1992 to July 1995. There were 20 men and 26 women, whose age ranged from 14 to 56 years. They were diagnosed hyperhidrosis in 21 cases, mediastinal tumor in 12 cases, pneumothorax in· 10 cases, and one case each of lelomyoma of the esophagus, Raynaud's syndrome, Burger's disease. Operation time averaged 89.7 minutes, and no patient was converted to d thoracotomy. The number of troche used, period of chest tube drainage, and postoperative hospitalization were 3, 1.8 days, and 4.B days, respectively. The postoperative complication ocurred in 5 cases (remnant pneumothorax 1 case, phrenic nerve aralysis 1 case, persistant air leakage 2 cases, compensatory hyperhidrosis 1 case). One patient with persistent air leak was managed by thoracotomy on postoperative) days, and the other patient by chemical pleurodesis. One patient diagnosed pathologically as thymic carcinoma, was managed by radiation therapy. There was no postoperative death. VATS has the benefits of reduced postoperative pain and postoperative hospitalization, and good cutsmetic effect.

• Investigative Magnetic Resonance Imaging
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• v.18 no.2
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• pp.144-150
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• 2014

Purpose : Intramedullary spinal lesions in the conus medullaris (CM), including tumors and vascular lesion, are rarely reported. We reported various MR features of intramedullary spinal cord lesions involving the CM including ependymoma, hemangioblastomas, dermoid cyst, ventriculus terminalis and spinal AVF and tried to discuss them for differential diagnosis. Materials and Methods: Six patients (male: female = 4:2, mean age = 44.3 year old) were enrolled from the clinical database of our institute from 2004 to 2010 and their radiological images and clinical symptoms were reviewed retrospectively. All patients had taken initial and postoperative MRI with contrast enhancement using gadopentate dimeglumine (Gd-DTPA). These images were analyzed by tumor size, location, signal intensity relative to the spinal cord, vascular flow voids, syrinx or cyst, edema and enhancement pattern. Results: Contrast enhancement was seen in all intramedullary masses. An eccentric enhancing nodule was noted in two hemangioblastomas and unusual peripheral rim enhancement with septation was seen in ventriculus terminalis. Patchy enhancement of the CM was observed in spinal arteriovenous fistula (AVF). Extensive cord edema adjacent to the intramedullary lesions was seen in four cases and syrinx was noted in three cases. Vascular signal voids were found in two hemangioblastomas and one spinal AVF. Conclusion: In evaluation of intramedullary spinal lesions in the CM, it is necessary to consider these unusual MR findings and discriminate various pathologies with prudence and caution.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.4 no.3
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• pp.170-179
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• 1999

The SUS (Signal, Underwater Sound)-OAT experiment was carried out in the Ulleung Basin of the East Sea on 3 June 1997. The SUS-OAT system consisted of aircraft deployed shots as sources and a vertical line array (VLA) tethered by a receiver ship was used to survey a large area where a mesoscale warm eddy appears frequently. The experiment was carried out such that explosive charges set to detonate at 800 ft depth were dropped in a rectangular ($120{\times}120$ km). Sources were a rapidly deployable SUS charge (MK 61 MOD 0), and receiver is a fixed VLA, 90 m in length (150-240 m in receiver depth), composed of 10 elements equally spaced. The reference ray paths are computed by range-dependent acoustic model in canonical ocean based on the historical data. The singular value decomposition (SVD) method is used to obtain the horizontal perturbation of the temperature fields. Horizontal distributions of temperature fields at 150 m and 200 m depth show a weak warm eddy observed by AXBT and the inversely estimated temperature shows similar patterns in terms of the location of the warm eddy. In conclusion, the SUS-OAT experiment has been successful to estimate the position of warm eddy and its temperature field in the East Sea of Korea.

• Journal of Advanced Navigation Technology
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• v.21 no.3
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• pp.230-242
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• 2017

A significant rise in product-liability cost is expected due to the newly passed product liability amendment Bill approved during the assembly plenary session on March 30, 2017. Korean government legal service(KGLS) filed a damage suit against Korea aerospace industries, Ltd.(KAI) and Hanwha Techwin Co., Ltd., the manufactures of the KUH-1 Surion helicopter crashed. KGLS alleged claims under the product liability Act, the warrant liability Act and the non-performance of contract act. The accountability limits of military aircraft manufacturers was a highly divisive issue among related scholars and legal practitioners. The bottom line was that military aircraft manufacturers had no product-liability insurance available. The United States courts have, therefore, developed the government contractor defense(GCD) and it was recognized by the U.S. Supreme Court in Boyle v. United Technologies corporation(1988). product liability insurances for military aircraft manufacturers are excessively expensive and it cannot be added onto the military procurement cost accounting. However, having an aircraft accident without one can be ruinously expensive. Therefore, the manufacturers should promptly set up appropriate risk management measures. This thesis will first review the advance GCD theory, and then find a way to either reform government contract related regulations.

• Journal of Korean Neurosurgical Society
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• v.46 no.4
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• pp.322-327
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• 2009

Objective : Posterior lumbar interbody fusion (PLIF) is considered to have the best theoretical potential in promoting bony fusion of unstable vertebral segments by way of a load sharing effect of the anterior column. This study was undertaken to investigate the efficacy of PLIF with cages in chronic degenerative disc disease with Modic degeneration (changes of vertebral end plate). Methods : A total of 597 patients underwent a PLIF with threaded fusion cages (TFC) from 1993 to 2000. Three-hundred-fifty-one patients, who could be followed for more than 3 years, were enrolled in this study. Patients were grouped into 4 categories according to Modic classification (no degeneration : 259, type 1 : 26, type 2 : 55, type 3 : 11). Clinical and radiographic data were evaluated retrospectively. Results : The clinical success rate according to the Prolo's functional and economic outcome scale was 86% in patients without degeneration and 83% in patients with Modic degeneration. The clinical outcomes in each group were 88% in type 1, 84% in type 2, and 73% in type 3. The bony fusion rate was 97% in patients without degeneration and 83% in patients with Modic degeneration. The bony fusion rate in each group was 81% in type 1, 84% in type 2, and 55% in type 3. The clinical success and fusion rates were significantly lower in patients with type 3 degeneration. Conclusion : The PLIF with TFC has been found to be an effective procedure for lumbar spine fusion. But, the clinical outcome and bony fusion rates were significantly low in the patients with Modic type 3. The authors suggest that PLIF combined with pedicle screw fixation would be the better for them.

• Atmosphere
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• v.16 no.3
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• pp.247-257
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• 2006

The Yeong-dong heavy snowfall forecast supporting system has been developed during the last several years. In order to construct the conceptual model, we have examined the characteristics of heavy snowfalls in the Yeong-dong region classified into three precipitation patterns. This system is divided into two parts: forecast and observation. The main purpose of the forecast part is to produce value-added data and to display the geography based features reprocessing the numerical model results associated with a heavy snowfall. The forecast part consists of four submenus: synoptic fields, regional fields, precipitation and snowfall, and verification. Each offers guidance tips and data related with the prediction of heavy snowfalls, which helps weather forecasters understand better their meteorological conditions. The observation portion shows data of wind profiler and snow monitoring for application to nowcasting. The heavy snowfall forecast supporting system was applied and tested to the heavy snowfall event on 28 February 2006. In the beginning stage, this event showed the characteristics of warm precipitation pattern in the wind and surface pressure fields. However, we expected later on the weak warm precipitation pattern because the center of low pressure passing through the Straits of Korea was becoming weak. It was appeared that Gangwon Short Range Prediction System simulated a small amount of precipitation in the Yeong-dong region and this result generally agrees with the observations.

• 한국해양학회지
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• v.18 no.1
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• pp.64-72
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• 1983

A series of sheps-of-opportunity sea sryface temperature (SST) measurement beween Jeju and Wando during a period from December 1979 through June 1981 produced following results. 1. A sihnificantly warm water appeared south of Chuja Island and Cheongsan Island during Island. It is suggested that this water represents a current entering the Jeju Strait from the west. Direction of this currint in other seasons is not certain. 2. Coastal waters were found north of the Cheongsan Island and Bogil Islhnd throughout the measurement period. In February these waters sometimes reached as far as Chuja Island to south. 3. Frequently thermal fronts were observed near the Chuja Island and the Cheongsan Island. 4. In summer cold waters appeared north of the Chuja Island and Changsu Island. Intrusion of cold bottom water from offshore and its subsequent vertical mixing due to strong tidal current are probably reponsible for this appearance. 5. Cold waters also appeared locally around islands and in ghe Jeju Harbor in spring and summer. 6. North-south SST difference reached 8-9$^{\circ}C$ in winter which is the annual maximum. 7. Annual range of SST varies from 12-14$^{\circ}C$ in the central part of the Jeju Strait to 16-20$^{\circ}C$ in coastal waters to north. The highest SST appeared everywhere in September but the lowest one did not appesr in the same month of year.

• Journal of The Korean Society of Grassland and Forage Science
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• v.35 no.1
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• pp.31-35
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• 2015

This experiment was carried out to breed a very early-maturing variety of Italian ryegrass (Lolium multiflorum Lam.) in the Grassland and Forage Crops Division, National Institute of Animal Science, RDA, Cheonan, Korea from 2012 to 2014. New variety "Greenfarm3ho" is a diploid variety with a green leaf color, a semi-erect growth habit in late autumn/fall, and an erect growth habit in early spring. With a heading date of April 27, Greenfarm3ho was categorized as an early-maturing variety. Compared with the "Greenfarm" control variety, Greenfarm3ho's flag-leaf width was narrower by 0.5 mm, its flag-leaf length was longer by 4.4 cm, and its plant length was longer by 3 cm; additionally, Greenfarm3ho's stem thickness was 0.1 mm thicker and it showed winter hardiness. The dry matter (DM) yield (8,976 kg/ha) of Greenfarm3ho was similar to that of Greenfarm. The in vitro dry matter digestibility (IVDMD), total digestible nutrient (TDN), and crude protein (CP) of Greenfarm3ho were 70.0%, 64.1%, and 1.0%, respectively, which are higher than those of Greenfarm by 2.9%, 2.0%, and 1.4%, respectively. The acid detergent fiber (ADF) and neutral detergent fiber (NDF) content of Greenfarm3ho were 31.4% and 53.3%, respectively, which are lower than those of Greenfarm by 2.5% and 3.0%, respectively.