• Journal of the Korea institute for structural maintenance and inspection
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• v.12 no.4
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• pp.79-86
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• 2008

Four RC shear wall specimens with a/d of 2.2 are designed. And a flexural retrofitting is performed for one specimen by both enlarging wall section and adding additional vertical reinforcements. Also the effectivity of jaketting wall sides is evaluated for the two methods using only steel plate or welded wire mesh with enlargement of section. Cyclic loads are applied to the retrofitted specimens according to the loading history proposed by ACI under constant axial force. Test result showed that the strength and ductility of specimen were improved where the section was enlarged after the installation of additional vertical reinforcements. Confining the ends of wall by U shape W.W.F. with enlargement of section showed most excellent structural capacity regarding to the strength and ductility. Retrofitting by using steel plate was much effective not only to protect the abrupt decrease of strength after yield but also to improve the deformation capacity.

• Korean Journal of Clinical Laboratory Science
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• v.37 no.2
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• pp.88-95
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• 2005

Even though the echocardiograph has been recognized as the method of choice among various diagnostic tools to detect congestive heart failure (CHF), there were some limitations in relation to the consumption of time, labor and process. We analyzed results of N-terminal probrain-type natriuretic peptide (NT-proBNP) and various parameters of the echocardiographic findings to clarify the diagnostic usefulness of NT-proBNP in detecting patients with CHF. We analyzed the sera from total of 242 cases from in-patients and out-patients, which were requested from the cardiovascular section of department of Internal Medicine at Chungnam National University Hospital from March 2003 to May 2004. The procedures were performed in order as shown below; sampling, NT-proBNP analysis, data acquisition and data analysis. All data including personal information and echocardiographic findings ware acquired by medical record review. When classifying the study population into six groups according to the degree of left ventricular ejection fraction (LVEF), the serum level of NT-proBNP was higher in the group with 51-60% of LVEF (P=0.023). There were low correlation between the serum level of NT-proBNP and various parameters of the echocardiographic findings with LVESD (r=0.1513), LVEDD (r=0.0831), LVEF (r=0.2035), IVST (r=0.03) and LVPWT (r=0.0728), respectively. When comparing NT-proBNP with atrial and/or ventricular enlargement, the patient group with both left atrial and left ventricular enlargement (p=0.186) or only left atrial (p=0.105) or only left ventricular enlargement (p=0.256) showed higher level of NT-proBNP without statistical significance than patient group with no enlargement. Searching the optimal cutoff of the serum level of NT-proBNP, the sensitivity (98.9%) and the specificity (100%) was highest at the cutoff of 300 pg/mL than any other cutoffs. These findings suggested that the analysis of NT-proBNP in serum might detect the patients with CHF earlier than with the echocardiograph, especially in patients with asymptomatic or mild symptomatic CHF. In conclusion, NT-proBNP test was proved to be clinically useful to diagnose CHF patients.

• Journal of Korean Society of Disaster and Security
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• v.12 no.2
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• pp.35-45
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• 2019

The enlargement and reduction of river channels can not only change the flow of water but also alter sedimentation patterns, thus hindering smooth flood conveyance. Accordingly, this study aims to analyze the effects of the sudden enlargement of river channels on changes in the riverbed and river flow. For this purpose, as part of the "Hometown River" Construction Project, this study examined the local river Kyungpo-cheon, which a section of the river channel was widened by at least two- to three-fold, using RMA-2 and SED-2D models to simulate the changes in flow characteristics and riverbed variation due to the widening of the channel. The results of the study indicated that widening the Kyungpo -cheon river channel secured its dimensional stability in comparison to before widening. however, due to a flood frequency of more than once per year, future maintenance and management will be costly and time-consuming.

• Journal of Korean Tunnelling and Underground Space Association
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• v.14 no.6
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• pp.637-652
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• 2012

The protector with the shape of '${\sqcap}$' in cross section can be set up in the tunnel, which can be constructed for enlargement of cross section, to keep traffic flow in the tunnel. It is impossible to install the rockbolt in the side wall of tunnel due to a limited space between the protector and cutting surface of side wall. The objective of this study is to suggest the optimum thickness of shotcrete lining without rockbolt on the side wall and to evaluate the stability of tunnel enlarged. Numerical analysis was performed to evaluate the displacement at the center of tunnel, the convergence of tunnel, and the stress in shotcrete lining in 4-lane NATM road tunnel enlarged from 3-lane NATM road tunnel. The vertical displacement at the center of tunnel and the convergence of crown in the tunnel with rockbolt in the side wall were almost similar to those in the tunnel without rockbolt in the side wall. The convergence of bench/invert and the stress in shotcrete lining without rockbolt on the side wall were greater maximum 0.57 mm and 1,300 kN/$m^2$ than those with rockbolt in the side wall. The increased convergence and the stress in shotcrete lining can be reduced in incerasing of thickness of shotcrete lining about 20% (5 cm) of standard thickness, 25 cm, of shotcrete lining.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.8
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• pp.120-125
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• 2000

This paper proposes a tilt sensor made by MEMS technology. The sensor consists of an electrode glass a small mercury drop a circular channel and a cover glass. The mercury drop is used as medium of a current flow and in contact with two circular chromel electrodes used as an angular-motion resistance When this sensor inclines the mercury drop inside the circular channel moves into the bottom under the influence of gravity. A tilt angle can be measured by changed resistance as tilting this sensor, This sensor has a linear section between +50.$^{\circ}$ and -50.$^{\circ}$ with the accuracy of 2.$^{\circ}$. We are also studying about the enlargement of the linear section and the effect of the size of the mercury drop.

• Journal of Veterinary Clinics
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• v.33 no.6
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• pp.368-371
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• 2016

A four month-old intact female Maltese (weighing 1.8 kg) was present with major complaints of severe coughing and dyspnea. Diagnostic imaging studies revealed abnormally elongated chordae tendineae attached to anterior leaflet and shortened chordae tendineae attached to posterior leaflet of mitral valve causing mitral insufficiency and regurgitant blood flow into left atrium, indicating congenital mitral valve dysplasia. Therapy was directed to control existing clinical signs and to prevent further deterioration of cardiac enlargement using conventional cardiac medications. The dog is currently survived and being monitored at regular interval. This is the first case report describing mitral valve dysplasia causing mitral insufficiency of dog in Korea.

• Tunnel and Underground Space
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• v.27 no.4
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• pp.195-204
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• 2017

This case study introduces the construction of large cross section tunnel for underground ventilation system in Sillim-Bongcheon Tunnel Project. In order to grant the safety and efficiency in connecting the ventilation shaft (7.8 m of width, and 6.6 m of height) to a tunnel for axial fan facility (20.8 m of width, and 12.3 m of height), gradual enlargement of tunnel cross section was employed between those and temporary support method was determined based on Q system. In addition, some original designs were revised during construction stage to improve the efficiency of excavation in large cross section tunnel. The advance length was optimized and top heading of the tunnel was excavated without partition in accordance with ground condition and numerical stability analysis results. It is believed that some experiences and considerations in this case study will be useful for the future design and construction in similar large cross section tunnel such as large underground ventilation system or road tunnel with four lanes.

• Proceeding of KASS Symposium
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• 2008.05a
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• pp.43-48
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• 2008

The object of this paper is to evaluate on constructability of modular steel frame with the hollow structural steel section to LEB C-shape. A modular building is built with factory-manufacture and site-construction. The advantage of a Modular building presents that enhanced building quality, shortened construction period and easy at an expansion and enlargement for buildings but also has demerits such as size restriction of the modular units according to the Road Traffic Law and Inflexibility of the unit composition. So in this study we use light-weighted structure members with bolted joint for easy Knock-down and traffic, also we evaluated the constructability of this bolted joints type modular buildings.

• Journal of Korean Association for Spatial Structures
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• v.8 no.4
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• pp.65-71
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• 2008

The object of this paper is to evaluate on constructability of modular steel frame with the hollow structural steel section to LEB C-shape. A modular building is built with factory-manufacture and site-construction. The advantage of a Modular building presents that enhanced building quality, shortened construction period and easy at an expansion and enlargement for buildings but also has demerits such as size restriction of the modular units according to the Road Traffic Law and Inflexibility of the unit composition. So in this study we use light-weighted structure members with bolted joint for easy Knock-down and traffic, also we evaluated the constructability of this bolted joints type modular buildings.

• Journal of Veterinary Clinics
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• v.25 no.2
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• pp.106-111
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• 2008

A 3-year-old intact female Maltese dog (2.5 kg of body weight) with the primary complaint of sudden onset of heart murmur, depression and anorexia was referred to the Veterinary Teaching Hospital of Kangwon National University. The dog was febrile with marked leukocytosis and left apical VI/VI holosystolic murmurs. The electrocardiogram implied the left ventricular enlargement. Diagnostic imaging studies revealed left atrial and ventricular dilation, severe vegetations on mitral valvular cusps with concurrent mitral regurgitation. Based on findings from clinical and diagnostic investigation, the case was diagnosed as vegetative mitral valvular regurgitation caused by infective endocarditis. The dog was successfully treated with broad spectrum antibiotics, diuretics, angiotensin converting enzyme inhibitor and antithrombotics.