• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.8
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• pp.4790-4795
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• 2014

The machine tool is used widely to manufacture and trial manufactured goods in many machinery industries. Blast-induced ground vibration may have an environmental impact, such as damage to the adjacent structures and facilities. This study examined the influence of blast vibration on the accuracy of machine tools. The blast vibration and vibration of machine tools was measured to evaluate the influence of blast vibration on machine tools. Based on the evaluation of the vibration limit of machine tools, the vibration criteria for machine tools in this study were SLIGHTLY ROUGH~ROUGH. By repeated blast vibration, machine tools are more likely show reduced accuracy.

• Journal of the Korean Society of Radiology
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• v.82 no.2
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• pp.298-314
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• 2021

Owing to the anatomic complexity of the hepatic hilum, it has been considered difficult to diagnose and treat peri-hilar cholangiocarcinoma. Currently, imaging studies, including contrast-enhanced CT and MRI, play a crucial role in the detection, characterization, staging, and resectability assessment of peri-hilar cholangiocarcinoma. In this review, the classification of perihilar cholangiocarcinoma and proposed imaging protocol for the evaluation will be discussed. The typical imaging finding of peri-hilar cholangiocarcinoma, evaluation of longitudinal tumor extent, adjacent vascular invasion, and distant metastasis will also be mentioned. Finally, traditional concepts and recent updates for the resectability assessment of peri-hilar cholangiocarcinoma will be introduced.

• Composites Research
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• v.35 no.6
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• pp.439-446
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• 2022

In this study, fiber-reinforced composite coil springs for automobiles were manufactured using the braiding method, and mechanical tests and damage evaluation were performed to confirm their safety. Through the analysis of the load-displacement behavior, the stiffness of the springs was evaluated to meet the specifications. In addition, the distribution of voids and the impregnation rate on the spring wire section were analyzed to clearly understand the criteria for the mechanical properties of the composite material. Moreover, the tested springs were visually inspected to confirm the damaged parts, and the failure mode was analyzed by observing crack initiation and propagation behavior of cross-sectional samples taken from the crack and failure adjacent areas of springs using SEM.

• Journal of the korean academy of Pediatric Dentistry
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• v.45 no.2
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• pp.203-214
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• 2018

Root resorption of the permanent maxillary incisors can occur due to ectopic eruption of the permanent canines. Severe root resorption threatens the long-term survival of the affected incisors. The aim of the present study was to identify risk factors for root resorption of the maxillary incisors associated with impacted maxillary canines. In the present study, we retrospectively analyzed the Cone-Beam Computed Tomography (CBCT) scans of 65 children and adolescents with ectopically erupting maxillary canines (total of 88 impacted canines). Root resorption of central incisors was significantly associated with the mesiodistal position and root development of the adjacent canine. Root resorption of lateral incisors was significantly associated with sex, age, and the buccolingual and vertical position of the adjacent canine. However, enlargement of the dental follicle was not significantly associated with root resorption of adjacent incisors. Although incisor resorption is difficult to diagnose and predict, our findings suggest that changes in the dental follicles of the erupting maxillary canines do not cause resorption of the adjacent permanent incisors. CBCT should be utilized to ensure early diagnosis of impacted canines and precise evaluation of incisor root resorption.

• The Journal of the Convergence on Culture Technology
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• v.6 no.4
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• pp.669-675
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• 2020

In this study, 3D analysis was compared in evaluating the track deformation of subway structures during adjacent excavation. For the 3D analysis model, the boundary conditions of the tunnel model and the application level of the ground water were analyzed as variables. As the result of the effects of track irregularity using the 3D model, the analysis model considering the site ground water level instead of the design values and changing the constraint of the boundary condition is more reasonable. In addition, the influence of track irregularity due to the boundary condition and load condition of the analytical model is more obvious in the factors directly affected by the longitudinal relative displacement of the rail, such as alignment, cross level and gauge irregularity. Therefore, the evaluation on track stability according to adjacent excavation work was appropriate to analysed the longitudinal deformation of the track by using 3D model that could be investigate the deformation of rail. In addition, the boundary condition and load condition(ground water level) of the numerical model was important for accurate analysis results.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.1
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• pp.310-315
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• 2017

Although studies evaluating the effects of the blasting vibration on the adjacent structures from various angles have continued, cases of securing the safety of the adjacent buildings and researching the proper blasting method for the field condition by analyzing the vibration waveform of the measuring field while performing the open pit blasting are poor. Therefore, it is necessary to present a remedy for blasting pattern selection through test blasting that is appropriate for field conditions, and is economical and efficient. In this study, open pit blasting work was conducted based on the separation distance applied according to the standard blasting method by test blasting and the vibration regulation standard in the road expansion construction site to measure the blasting vibration value, and the vibration prediction equation by blasting methods was examined using a regression analysis computer program to calculate K, N, and R of the confidence level 95%. By setting the blasting allowed vibration standard of the test blasting target area to 0.3cm/sec, and the charring weight and blasting method by the separation distances according to the blasting vibration estimation equation of the open pit blasting guideline and the blasting vibration estimation equation of the test blasting were compared/analyzed, it was possible to identify the factors that increased the working expenses. In addition, the measurement and analysis of the adjacent structures during open pit blasting and the blasting vibration were performed after selecting the most adjacent structure to the open pit blasting spot to analyze the problems on the test blasting procedure and analysis method in the open pit blasting design/construction guidelines, which appeared in the process of completing open pit blasting construction, and a remedy is presented.

• Journal of the Korean Institute of Landscape Architecture
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• v.29 no.1
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• pp.67-79
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• 2001

The purpose of this research is to evaluate the biotope value in a metropolitan area after constructing the biotope evaluation model to develop biotope networking in the light of ecological landscape planning. In addition this study is to provide a basic frame of constructing the biotope networking system in the future with the evaluation results. The scope of this research is limited to high density residential area including some part of the forest adjacent to urban boundary. The results of the classified biotope in the research area have been turned out to be 24 patterns. According to the result of estimated nature value having the forth grade, three were forests combined with urban natural parks, schools near forests, and grasslands. There is a little place having first grade. We an deduce this fact that we have surveyed biotopes, having the minimum nature value and wider than children's park. As for the result of evaluated the structure, there were the forests of Seong-Dong, Meaho-Dong, and Kumho river, which is the forth grade. As for the evaluation of connection-function, the followings area were evaluated as the third grade-linear biotopes having highly valued and sustainable similarity - Seoul-Pusan Railroad, Dong-Daegu St., Kumho river, river basins. Bum대 park and a botanic park near Suesung lake, As for the evaluated the buffer-function, higly valued production biotopes, existing at a transition belt between he residential density areas, are Sawol-Dong, Meaho-Dong and Kumho river. When each of the indexes was evaluated, the core of the biotop contained most of natural biotopes. Large artificial biotopes were evaluated as an important biotopes, while small artificial biotopes were classified as a dot biotope. The future research on the concrete biotope networking construction, based upon performed evaluation in this research, should be conducted.

• Journal of the Korean Institute of Rural Architecture
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• v.25 no.4
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• pp.37-44
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• 2023

As a basic study to analyze the relative importance of external space in urban development projects, this study selects evaluation indicators for external space planning and then analyzes systematic external space planning through expert surveys. The scope of the study is to examine the criteria of evaluation items for external space derived from existing studies and to suggest the importance and priority of evaluation items. As a research method, we reviewed the legal and research literature on landscape planning and external space-related guidelines, and conducted a primary review of external space planning evaluation items analyzed by questionnaire. The reviewed items were again reviewed and selected through expert group discussions (FGI). The selected evaluation items were surveyed by expert groups and analyzed in depth using the hierarchical analysis method (AHP). Looking at the relative importance of the calculated sub-items, among the 17 sub-items, 'planning open space' (.096) is the largest, followed by 'pedestrianization' (.082), 'linking with adjacent buildings, streets, parks, and green areas' (.077), 'securing public space through various planning techniques such as linking with pedestrian paths' (.066), 'Plan the placement, form, and scale of buildings in consideration of the identity of the destination' (.065), 'Plan buildings, streets, parks, and green spaces in an integrated and holistic manner' (.065), 'Harmonize with the surrounding environment (landscape)' (.063), 'Harmonize with surrounding buildings and apply landscape planning in urban planning' (.063), 'Entrances and lower floors of buildings are planned as parks for users and pedestrians' (.060), 'Preserve and expand green areas and establish maintenance plans for urban greening' (.054), 'Form the basis for a comfortable life for urban residents by providing long-term development directions' (.047), 'Activate community activities and plan pedestrian environments and streetscapes considering human scale' (.047), 'Establish and propose basic directions for urban greening' (.046), 'Plan buildings, streets, parks, and green areas considering the hierarchy and characteristics of the landscape structure' (.045), 'Plan for integrated land use' (.045), 'Create green axes in connection without cutting them due to development activities' (.044), and 'Apply barrier free design' (.034).

• Journal of the Korean Arthroscopy Society
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• v.2 no.2
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• pp.124-128
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• 1998

From Feb. 1996 to Feb. 1997. among sixty-four patients of anterior cruciate ligament(ACL) reconstruction using multi-stranded hamstring tendon and EndoButton fixation, twenty-five patients of volunteer, 15 men and 10 women, from 16 to 50 years of age(mean 27.6 years) underwent arthroscopic evaluation. Arthroscopic evaluation was routinely performed one year after surgery along with an examination of stability. The purpose of this study was to arthroscopically evaluate the morphological changes that occurred in hamstring tendon autograft one year after ACL reconstruction. Both of the tendon graft and the adjacent fibrous tissues were observed for gross appearance and physical properties with probing and response to passive anterior translation. Biopsy samples were taken from the surrounding fibrous tissue and the tendon graft. Grossly, we found a well-defined ligamentous structure with good tension tested with a probe. A common finding was that the reconstructed ligaments were embedded in a layer of the synovium, and blood vessels could be seen on the anterior surface of the ligament. The biopsy tissue was placed in formalin solution and subjected to histological preparation by hematoxylin and eosin staining method. The hamstring tendon graft appeared histologically normal under light microscopic finding. There were a few vessels located between existing collagen bundles, and the vessels had an orderly pattern. The surrounding fibrous tissue envelope was covered with synovium. We pleased with preliminary findings in our evaluation.

• Convergence Security Journal
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• v.19 no.2
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• pp.129-136
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• 2019

The main tasks of commander and staffs in ground operations are a continuation performing the process of making decisions in various situations. Since the current decision-making process is largely dependent on qualitative methods, it is difficult to integrate with the decision-making tools associated with the 4th Industrial Revolution. The purpose of this study is to suggest the process of deriving the relative importance of the evaluation factors using the AHP with focusing on assessing the avenues of approach in IPB related to the ground operation plan. The most important aspect of IPB is the evaluation of the avenues of approach. Evaluation factors include target accessibility, observation and seasons, concealment and cover-up, ease of maneuverability, and ease of transition to adjacent access roads. The existing methods are the comparison method with evaluation factors and the analysis with the advantages and disadvantages. However, it has been criticized that they regard evaluation factors as equal importance. The results show that target accessibility has the highest score related with priority when considering the criteria.