• Journal of Institute of Control, Robotics and Systems
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• v.19 no.2
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• pp.171-176
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• 2013

X-ray cross-sectional image-based inspection technique is one of the most useful methods to inspect the brazing joints of heat exchanger. Through X-ray cross-sectional image acquisition, image processing, and defect inspection, the defects of brazing joints can be detected. This paper presents a method to judge the type of detected defects automatically, and to display them three-dimensionally. The defect type is classified as unconnected defect, void, and so on, based on location, size, and shape information of defect. Three-dimensional display which is realized using OpenGL (Open Graphics Library) will be helpful to understand the overall situation including location, size, shape of the defects in a test object.

• Structural Monitoring and Maintenance
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• v.9 no.3
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• pp.221-235
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• 2022

Among nondestructive damage detection methods, impedance-based methods have been recognized as an effective technique for damage identification in many kinds of structures. This paper proposes a method to detect cracks in metal structures by combining electro-mechanical impedance (EMI) responses and artificial neural networks (ANN). Firstly, the theories of EMI responses and impedance-based damage detection methods are described. Secondly, the reliability of numerical simulations for impedance responses is demonstrated by comparing to pre-published results for an aluminum beam. Thirdly, the proposed method is used to detect cracks in the beam. The RMSD (root mean square deviation) index is used to alarm the occurrence of the cracks, and the multi-layer perceptron (MLP) ANN is employed to identify the location and size of the cracks. The selection of the effective frequency range is also investigated. The analysis results reveal that the proposed method accurately detects the cracks' occurrence, location, and size in metal structures.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.6 no.2
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• pp.9-16
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• 2007

The fatigue test of the fillet weldments were executed with different groove angles and porosity. The groove angles of $90^{\circ}$, $45^{\circ}$ and $55^{\circ}$ were compared with fatigue lives. After the fillet weldment failure, the porosity which found at the fractured surface were observed to account the effect on fatigue life. Finite element analysis were performed to correlate the fatigue strength and the size & the location of porosity. The stress-strain field were severely affected by the length of notch and the size & location of porosity. Based on the quantitative analysis of porosity effect, the total volume of porosity was key factor for fatigue strength of the fillet weldment.

• Journal of Agricultural Extension & Community Development
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• v.18 no.3
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• pp.435-483
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• 2011

This paper was to study characteristics of school types based on classification of rural areas. This study tried to provide basic data for implementing the development of rural education policy for the community unit by classifying and analyzing administrative districts. For the purpose, the researcher carried out literature reviews and selected three schools considering the gaps in size and location of rural community. The researcher interviewed teachers and parents, to gather information about rural education, and conducted participant observation on educational activities. As a result, this study showed each rural school has its own distinct characteristics by the school types corresponding to each rural community. Characteristics with school types were influenced by school location, possible migration into the cities, possible opportunities of private tutoring, school size, social class distribution, socio-economic status, dwelling pattern of school teachers. In conclusion, it is important that the educational policies for rural area consider the different characteristics of rural schools.

• Journal of Fisheries and Marine Sciences Education
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• v.17 no.1
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• pp.76-85
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• 2005

GIS (Geographic Information Systems) technology is a necessary function to support location based on service by using GPS in the mobile environment. These mobile systems have basic functional limitations such as a low rate of processing, limited memory capacity, and small screen size. Because of these limitations, most of the mobile systems require development of a reduced digital map to overcome problems with large-volume spatial data. In this paper, we suggest using the reduced digital map format in order to use location based on service in a PDA environment. The processing of the proposed data format consists of map generation, redefinition of layers, creating polygons, and format conversion. The proposed data format reduces the data size by about 98% comparing with DXF format based on the digital map of Busan.

• Structural Engineering and Mechanics
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• v.13 no.6
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• pp.653-670
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• 2002

In order to ensure the structural dynamic stability of moving liquid-storage containers, the flow motion of interior liquid should be appropriately suppressed by means of mechanical devices such as the disc-type elastic baffle. In practice, the design of a suitable baffle requires a priori the parametric dynamic characteristics of storage containers, with respect to the design parameters of baffle, such as the installation location and inner-hole size, the baffle number, and so on. In this paper, we intend to investigate the parametric effect of the baffle parameters on the transient dynamic behavior of a cylindrical fuel-storage tank in an abrupt vertical acceleration motion. For this goal, we employ the ALE (arbitrary Lagrangian-Eulerian) kinematic description method incorporated with the finite element method.

• Journal of the Korean Operations Research and Management Science Society
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• v.13 no.2
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• pp.25-33
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• 1988

An efficient heuristic solution procedure is developed for the minimum location problems. The gradient direction method and modified gradient approach are developed due to the differentiability of the objective functions. Suboptimal step size is obtained analytically. A Modified Gradient Procedure (NGP) is presented and compared with the hyperboloid approximation procedure (HAP) which is one of the best known methods.

• The Korean Journal of Health Service Management
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• v.8 no.2
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• pp.1-10
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• 2014

This study examined nonpatient revenues of university hospitals in korea. The data source for this study was 22 university hospitals over the period 2010-2012. In this study, patient revenues, patient expenses, operating profit, nonpatient revenues, total revenues, operating margin, normal profit to gross revenues, ratio of the nonpatient revenues in the total revenues were analysed by the annual and three-year average. The analysis of nonpatient revenue differences by hospital type, bed size, location, management performance was performed by T-test and oneway ANOVA. The results were as follows. First, nonpatient revenues of university hospitals were increased during the period 2010-2012. Second, nonpatient revenues according to hospital type, bed size, location in the university hospitals had significant difference. Third, hospital type was significantly associated with normal profit to gross revenues which was profitability index about nonpatient revenues. Based on these results, this study suggests implications to diversify for management performance in hospitals.

• Journal of Veterinary Clinics
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• v.20 no.4
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• pp.508-515
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• 2003

A 4-month-old 5.7 kg male Golden retriever with history of seizure, depression, lethargy and anorexia was referred to Veterinary Medical Teaching Hospital, Chungbuk National University. Hematologic examination revealed microcytosis and nonregenerative anemia. Serum chemical values showed increased serum ammonia (423 $\mu$mol/L), ALP (1101 U/L), r-GTP (13.9 U/L) and CPK (1454 U/L), and decreased total protein (4.9 g/dl) and BUN (1.6 mg/dl). Microhepatia was shown in survey abdominal radiographs. Color doppler ultrasonographic examination revealed dilated tortuous vein with turbulent flow within liver parenchyma. Intraoperative jejunoportography and intraoperative ultrasonography confirmed the location and size of single intrahepatic shunt vessel in the left medial liver lobe. Also, the anomalous vessel entering the caudal vena cava was identified beneath the diaphragm. The shunting vessel was ligated with using an Ameroid constrictor. General conditions, hematologic and serum chemical values resolved gradually after surgery. One month after surgery abdominal radiograph showed normal gastric axis and it was consistent whit the normal size liver. Normal echogenecity of liver and enlargement of portal vein were shown in ultrasonography. It is assumed that survey radiography and ultrasonography are useful for diagnosis of single intrahepatic shunt in a dog and especially jejunoportography vein portography and intraoperative ultrasonography are suitable for confirmation of the anatomic location and size of the shunting vessels.

• Korean Management Science Review
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• v.34 no.1
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• pp.15-25
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• 2017

We evaluated industry growth and employment effects of every possible pairs of 22 manufacturing sectors and 16 regions (i.e, 352 region-sectors). We used annual data of manufacturing sectors from 2008 to 2014 for the evaluation. The evaluation comprises of two steps; We first find several region-sectors that outperform others with respect to the effects of industry growth and employment, which are measured by location quotient analysis, shift share method, employment to GDP ratio and employment elasticity. In addition, cross-efficiency analysis follows to classify region-sector pairs into two sub-categories : efficient region-sectors that deserve to hold the current level of investments and inefficient region-sectors where we should consider efficiency improvements. To examine the efficiency, R&D investment, employment size, and capital investment were used as input factors and production volume, added value, changes in employment size, changes in annual salary per capita were used as output factors. For region-sector pairs that have outstanding growth and employment effects but are inefficient, we employed a CCR DEA model and analyzed how much to adjust the values of input and output factors to improve the efficiency scores. The analysis results showed that inefficiency is mainly due to several factors such as R&D investment, changes in employment size and changes in annual salary per capita.