• Tunnel and Underground Space
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• v.20 no.5
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• pp.344-351
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• 2010

Slip along a frictional fracture can be approached as initiation and propagation of a mode II crack along its own plane. Fracture mechanics theories predict that under pure mode II loading initiation will occur when the energy release rate of the fracture attains a critical value ($G_{IIC}$), which is generally taken as a material property. For the past few years the rock mechanics group at Purdue University has investigated experimentally the dependence of $G_{IIC}$ on normal stress and on the frictional characteristics of a fracture. A number of experiments has been conducted first on acrylic, a material that, using photoelastic methods, allows visualization of the stress field ahead of the fracture tip; and later on gypsum, a rock model material with relatively low unconfined compression strength. The experimental investigation has been expanded to include other frictional materials with higher unconfined compression strength. Direct shear tests have been conducted on specimens made with cement paste. New observations together with previous experiments indicate that $G_{IIC}$ can only be considered a material property when the peak friction angle of the discontinuity is similar to the residual friction angle; otherwise the critical energy release rate increases with normal stress.

• Journal of KIISE:Computing Practices and Letters
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• v.11 no.5
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• pp.436-450
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• 2005

Existing B2B, B2C computer systems and applications that executed business trans-actions were the client- server based architecture which consists of heterogeneous hardware and software including personal computers and mainframes. Due to the active boom of electronic business, integration and compatibility of exchanged data, applications and hardwares have emerged as hot issue. This paper designs and implements a message transport system and a document transformation system in order to solve the interoperability problem of integrated logistics system in e-Business when doing electronic business. Message transport system integrated ebMS 2.0 which is standard business message exchange format of ebXML, the international standard electronic commerce framework, and JMS of J2EE enable to ensure reliable messaging. The document transformation system could convert non-standard XML documents into standard XML documents and provide the web services after integrating message system. Using suggested business scenario and various test data, our message oriented system preyed to be interoperable and stable. We participated ebXML messaging interoperability test organized by ebXML Asia Committee ITG in oder to evaluate and certify the suitability for message system.

• Journal of the Korean Child Neurology Society
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• v.26 no.4
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• pp.221-226
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• 2018

Purpose: Febrile seizures (FSs) are the most common type of seizure in the first 5 years of life and are frequently associated with viral infections. Influenza infection is associated with a variety of neurological conditions, including FSs. The purpose of this study was to evaluate the clinical implications of influenza infection in FSs. Methods: In total, 388 children with FS were divided into two groups: FS with influenza infection (n=75) and FSs without influenza infection (n=313). Their medical records, including seizure type, frequency, duration, and familial history of FSs or epilepsy, were retrospectively reviewed and the clinical characteristics of the two groups were compared. Results: In total, 75 of the 388 children (19.3%) had FSs associated with influenza infection; such children were significantly older than those with FSs without influenza infection ($34.9{\pm}22.3$ months vs. $24.4{\pm}14.2$ months; P<0.001). The children who had more than two febrile seizures episodes were more prevalent in children with FS with influenza infection [40/75 (53.3%) vs. 92/313 (29.4%); P<0.01]. Children older than 60 months were more likely to have influenza infection compared to those aged less than 60 months [11/22 (50%) vs. 64/366 (17.5%); P=0.001]. Conclusion: Influenza infection may be associated with FSs in older children, and with recurrence of FSs. Its role in the development of afebrile seizures or subsequent epilepsy requires further investigation with long-term follow-up.

• Journal of the Korea Society for Simulation
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• v.28 no.2
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• pp.35-48
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• 2019

Domestic hydraulic drifters till now have been developed by benchmarking products from overseas leading companies. However, they do not have excellent impact performance as they are not suitable for characteristics (large flow rate and low pressure) of Korean hydraulic drill power pack, and therefore, research on the optimum design has not made much headway. This study performs multi-objective function optimization for hydraulic drifters whose capacity has been redesigned to deal with the large flow rate, and also with the help of this function, it aims to improve impact power and reduce supply and surge pressure. A summary of the research study is as follows: First, we set goals for improving impact power, supply pressure, and surge pressure, and then perform multi-objective function optimization on them. After that, we secure the reliability of the optimized analytical model by comparing the test results of the prototype built by the optimized design with the analysis results of the analytical model. This study used SimulationX, that is the hydraulic system analysis software, and EasyDesign, which is a multi-objective function optimization program. Through this research, we have achieved the results that satisfy the goal of developing high power drifters suitable for Korean type hydraulic drills.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2014.10a
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• pp.79-81
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• 2014

Recently, It is built various information systems evolve IT skills. But When you build the information system, Difficult to determine whether the appropriate scale and problems that rely heavily on SI companies and professionals. To solve this problem, Korea Information Security Agency, etc., based on the primary objective was to develop H/W Capacity Equation formally to each system type. But the problems are to present H/W capacity equation by discussion of the expert group of suppliers and relatively long that it is difficult to formally apply in the situation now so it is no longer the limit. In this study, we proposes proper capacity planning techniques, which can guarantee the best performance compared to the budget invested. For this purpose, we derived the proper H/W capacity equation by regression analysis to gather performance metrics and cost of various cases by simulation of a virtual environment in the cloud. Through this study, when capacity planning, It is possible to reduce costs that It is possible to build an information system based on the digitized data and build information system in an environment that does not rely on the SI business or professional.

• Journal of the Korean Institute of Landscape Architecture
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• v.47 no.1
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• pp.49-56
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• 2019

Urban green spaces have been contributing to the improvement of environmental, mental, and physical health for humans. In addition, recent studies showed the potential role of vegetation in reducing the amount of crime in inner-city neighborhoods at the micro-scale level. However, little is known about the positive role of urban green areas in improving urban safety at the regional level. The purpose of this study is to examine the relationship between urban green areas and actual outdoor crime rates, while also considering socio-demographic factors. The study area is the city of Austin, Texas, USA, which consists of 506 block groups. This study utilized socio-demographic factors based on U.S. Census data and vegetation-related factors utilizing GIS and ENVI software. For analyses, the analysis of variance (ANOVA) and an ordinary least square (OLS) regression were utilized. The results from ANOVA showed that yearly crime rates per acre for areas having 0%~25% trees in their neighborhoods were 0.46% and 1.05% higher than those of having 25%~50% and >50% trees in the neighborhoods, respectively. The results from the OLS regression represented that income, NDVI and park rates in neighborhoods were negatively associated with the crime rate per acre, whereas the percentage of minorities and the percentage of teenage school dropouts were positively associated with the crime rate per acre. This study implies that urban green areas may help to improve the safety of urban areas.

• Journal of Dental Rehabilitation and Applied Science
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• v.36 no.4
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• pp.232-241
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• 2020

Purpose: This study investigated the complications and patterns of implants that confronted with the extruded natural teeth. Materials and Methods: Among patients who received implant treatment between 2006 and 2018 at Chosun University Dental Hospital, only implants that had a maintenance period of at least 5 years and that both implants and confronting natural teeth could be measured and compared on a radiograph were selected. They were divided into two groups. Group 1, experimental group consisted of Implants confronting the extruded natural posterior teeth (n = 167: maxilla (Group 1max) = 92, mandible (Group 1man) = 75) and Group 2, control group consisted of Implants confronting the normal natural posterior teeth (n = 656: maxilla (Group 2max) = 272, mandible (Group 2man) = 384). Results: The incidence of complications between Group 1 and Group 2 was statistically significant. In particular, there was a statistically significant difference between the frequency of marginal bone loss and the amount of marginal bone loss. Conclusion: The extruded natural tooth may cause more frequent complications including bone resorption in the opposing implant.

• Journal of Food Hygiene and Safety
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• v.35 no.6
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• pp.607-617
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• 2020

Human bio-monitoring (HBM) data is a very important resource for tracking total exposure and concentrations of a parent chemical or its metabolites in human biomarkers. However, until now, it was difficult to execute the integration of different types of HBM data due to incompatibility problems caused by gaps in study design, chemical description and coding system between different sources in Korea. In this study, we presented a standardized code system and HBM knowledge model (KM) based on relational database modeling methodology. For this purpose, we used 11 raw datasets collected from the Ministry of Food and Drug Safety (MFDS) between 2006 and 2018. We then constructed the HBM database (DB) using a total of 205,491 concentration-related data points for 18,870 participants and 86 chemicals. In addition, we developed a summary report-type statistical analysis program to verify the inputted HBM datasets. This study will contribute to promoting the sustainable creation and versatile utilization of big-data for HBM results at the MFDS.

• Journal of Naturopathy
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• v.11 no.1
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• pp.1-8
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• 2022

Background: A validation study is needed to make domestic applications of German Kneipp therapy. Purpose: The study aims to test the effect of a Kneipp therapeutic program in a domestic forest environment on the autonomic nervous system. Methods: The program was made considering the 4 key elements ('exercise', 'regulative therapy', 'nutrition', and 'phytotherapy') of the Kneipp therapy. Total 3 sessions (once a week for 5 hours in each session) were performed to 40 domestic adults divided into four groups (10 in each group). HRV was measured on the subjects before and after the intervention, and its 6 characteristic parameters (TP, VLF, LF, HF, LF/HF, CSI: Cumulative Stress Index) were compared for statistical analysis. Results: For 33 subjects excluding 7 who were disturbed by interrupt factors during measurements, significant improvements after the intervention, were observed in TP(8.64%, p < ..001), VLF(6.96%, p < .05), LF(15.86%, p < .001), HF(8.46%, p < .01), LF/HF(5.77%, p < .05) and CSI(-16.06%, p < ..001). Conclusions: The Kneipp therapy performed in the forest environment was shown to activate the autonomic nervous system and in particular the sympathetic and parasympatheric nervous to promote heart activity, and was also shown to most significantly reduce cumulative stress. The present observations would be the first preliminary evidence that the Kneipp therapeutic interventation in a domestic forest environment results in positive responses of the autonomic nervous system including stress relief.

• Journal of Naturopathy
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• v.10 no.1
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• pp.1-9
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• 2021

Purpose: This study has proved the intervention effects of the proposed logotherapy-based music imagery (LBMI) program on the self-worth of the personal assistants for the disabled. The program, in the image activities and at the stage of postlude after listening to music, unites logodrama of logotherapy, paradoxical intention and dereflected techniques. The intervention effects of the LBMI program were tested for the 28 personal assistants for the disabled who found themselves without the value and meaning of life and were randomly equally divided into the experimental and control groups. This intervention was carried out for the six different terms, each of which was alloted 60 minutes. To evaluate the intervention effects, the self-worth scale were examined before and after the intervention for both experimental and control group. The result shows that the self-worth improved significantly in the experimental group(p < 0.001), whereas it remained unchanged in the control group(p > 0.459). This finding proves that the proposed LBMI program ameliorates the self-worth of the personal assistants for the disabled.