• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.1
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• pp.61-70
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• 2013

This paper presents the response calibration method based on quality control range, which is established from the concept and method of statistical quality control for natural frequency ratio and response ratio. To this end, statistical analysis including descriptive statistics analysis, normality test, ANOVA were performed for response characteristics obtained from loading tests and structural analysis for more than hundred and thirty well-conditioned bridges. Suggested method is based on real structural integrity evaluation case studies and statistical quality control approach, in this respect it is expected to provide scientific criteria and systematic procedure for response calibration and load carrying capacity assessment.

• Journal of computational fluids engineering
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• v.11 no.3 s.34
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• pp.8-13
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• 2006

The north panel of a geostationary satellite is used as one of the main radiators, on which communication equipment or bus equipment are installed. The thermal control of panel is designed by using embedded heat pipes and surface heat pipes (or external heat pipes) to spread out heat dissipated from equipment all over the radiator evenly and finally to reject the heat to the space through the radiator efficiently. This panel is also divided by several areas based on the operating temperature and dissipation of equipment in order to increase heat rejection capability of radiator. The thermal analysis is carried out for the hot case, Winter Solsitce EOL (End Of Life), in order to validate thermal design of the panel utilized 6 surface heat pipes and 8 embedded heat pipes. The sensitivity studies for the heat pipe failure case and no heat pipe case are performed and compared to its normal state. The heat transport capability of heat pipe is also obtained from these calculations.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.21
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• pp.9107-9112
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• 2014

Purpose: To investigate and study the relationship between the PLCE1 rs2274223 gene polymorphism and susceptibility to esophageal cancer by meta-analysis. Materials and Methods: The literature was searched in Wanfang, CNKI, PubMed, CBM, Web of Science, MEDLINE, EMBASE, Springer, Elsevier and Cochrane databases from the date of January $1^{st}$ 2004 to April $1^{st}$ 2014 to collect case-control studies on the PLCE1 polymorphism and susceptibility to esophageal cancer. For the population genotype distributions of both esophagus cancer and control groups, their odds ratios (ORs) and 95% confidence intervals (CIs) were taken as effect indexes. Disqualified studies were excluded. Odds ratios of PLCE1 rs2274223 genotype distributions in the group of patients with esophageal cancer and the group of healthy control were calculated. The metaanalysis software, RevMan5.0, was applied for heterogeneity test, pooled OR and 95% confidence intervals. Sensitivity analysis and publication bias were also explored. Results: A total of twelve case-control studies were included, covering a total of 9, 912 esophageal cancer cases and 13, 023 controls were included. The pooled odds ratio of PLCE1 rs2274223 genotype GA vs AA was 1.29 (95%CI=1.17~1.43), p<0.01, GG vs AA was 1.65 (95%CI=1.32~2.05), p<0.01, GG/GA vs AA was 1.30 (95%CI=1.16~1.46), p<0.01 and GG vs GA/AA was 1.48 (95%CI=1.22~1.80), p<0.01. The PLCE1 rs2274223 polymorphism was thus associated with risk of esophageal cancer in all genetic models. In the stratified analysis by ethnicity, and source of controls, no significantly increased risk was observed for white persons. There was no obvious publication bias detected. Conclusions: This meta-analysis showed there was a significantly association between PLCE1 rs2274223 polymorphism and esophageal cancer in yellow race populations. Due to some minor limitations, our findings should be confirmed in further studies.

• Journal of Welding and Joining
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• v.21 no.4
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• pp.80-86
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• 2003

Arc-spot welding is generally used in joining of precise parts such as case and core in electric compressor. It is important to control joining deformation in electric compressor because clearance control of micrometer order is needed for excellent airtightness and anti-nose. The countermeasures for this deformation in field have mainly been dependent on rule of try and error by operator's experience because of productivities. For control this deformation problem without influence on productivities, development of exact simulation model should be needed. In this study, on the basis of previous study, the analysis model io predict deformation of precise order in arc-spot welded structure with non-uniform stiffness is brought up through feedback and tuning between monitoring data and analysis results. For this, deformation monitoring system was built and boundary condition considering mechanical melting temperature was applied.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.53 no.1
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• pp.13-21
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• 2004

In the design of superconducting cable systems, quench analysis have to be advanced for applying to a real systems. It is necessary to calculate the current, voltage and resistance during the quench. Simulation program named EMTDC was used to analyze the quench state. Normal zone evaluation and quench development with EMTDC are one of the major features of quench analysis. This paper presents the two kinds of quench control models which are the Switch Control Type and the Fortran Control Type. In case of the quench developing area, the simplicity cable model consist of resistance, inductance and capacitance. The impedance of the pipe type superconducting cable is calculated by numerical analysis method. The resistance and inductance increased during quench. However the variation have an effect on the fault current. The voltage was also developed by resistance and inductance. This paper presents the relationship between the current. voltage, resistance and inductance during quench.

• Journal of Korean Society for Quality Management
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• v.22 no.4
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• pp.79-101
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• 1994

In modern manufacturing, a product consists of many components created by different processes. Variations in the individual component dimensions and in the processes may result in unacceptable final assemblies. Thus, engineers have increased pressure to properly set tolerance specifications for individual components and to control manufacturing processes. When a proper variation stack-up analysis is not performed for all of the components in a functional system, all component parts can be within specifications, but the final assembly may not be functional. Thus, in order to improve the performance of the final assembly, a proper variation stack-up analysis is essential for specifying dimensional tolerances and process control. This research provides a detailed case example of the use of variation stack-up analysis using a Monte Carlo simulation method to improve the defect rate of a complex process, which is the commutator brush track undercut process of an armature assembly of a small motor. Variations in individual component dimensions and process mean shifts cause high defect rate, Since some dimensional characteristics have non-normal distributions and the stack-up function is non-linear, the Monte Carlo simulation method is used.

• Journal of the Korean Society for Precision Engineering
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• v.12 no.11
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• pp.82-90
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• 1995

This paper pressents a condition-based maintenance (CBM) method through bibration analysis. The well known frequency analysis is employed for performing machine fault diagnosis. The statistical control chart is also applied for analyzing the trend of the bearing wear. Vibration sensors are attached to prototype machine and signals are continuously monitored. The sampled data are utilized to evaluate how well the fast fourier transform(FFT) and the statistical control chart techniques could be used to identify defects of machine and to analyze the machine degradation. Experimental results show that the propowed approach could classify every mal-function and could be utilized for real machine diagnosis system.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.6
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• pp.1470-1479
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• 2009

The purpose of this study was to investigate the relationship of Dampness-phlegm to blood lipid level and second reason of hyperlipidemia in acute stroke patients by case-control study. This study was done over 348 patients hospitalized in the Oriental Medical Hospital of Daejeon University of November 2006 to July 2008. Patients had been interviewed by residents and medical specialists who studied standard operation procedures in Fundamental Study for Syndrome of Oriental Medicine for Stroke. Study subjects consisted of 86 patients who distributed to Dampness-phlegm by medical specialist and discriminating program as the case I group, 157 patients who distributed to Dampness-phlegm by medical specialist or discriminating program as the case II group and 191 patients who distributed to Non-Dampness-phlegm by medical specialist and discriminating program as the control group. For the purpose of obtaining suitable result we analyzed blood lipid level of each group by univariate and multivariate logistic analysis. Dampness-phlegm was not significant correlated with increasing of Total cholesterol, Triglyceride and decreasing of HDL cholesterol. Dampness-phlegm was significant correlated with increasing LDL cholesterol and the independent predictors of hyperlipoproteinemia by multivariate logistic analysis. Dampness-phlegm was not significant correlated with diabetes melitus, liver disease, kidney disease, obesity and abdominal obesity. In this study, we demonstrated new relationship between Dampness-phlegm and LDL cholesterol. Based on these results, it is suggested that Dampness-phlegm would be the independent predictors of hyperlipoproteinemia. And more prospective studies are to be done with more clinical data.

• The Journal of Korean Academy of Prosthodontics
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• v.46 no.4
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• pp.381-395
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• 2008

Purpoose: For decades dental implants have been used widely in the field of prosthetic dentistry. However there is confusion when establishing treatment plans in cases where some teeth are remained but an insufficient number of implants can be used due to limited anatomical status and ecomomical problems. Many clinicians have tried to connect natural teeth and implants, and it still has controversy. But, there have been few studies on mechanical analysis of connecting natural teeth and implants with konus telescopic removable partial dentures. The purpose of this study was to analyze the stress distribution of prosthesis, abutment and alveolar bone when teeth and implants were connected with the konus telescopic denture, by means of 3-dimensional finite element analysis. Material and methods: The assumption of this study was that there were 2 mandibular canine (11 mm in length, 4 mm in diameter) and 2 implants(10 mm in length, 4 mm in diameter) which are located in the second premolar region. The mandible, teeth, implants, abutments, and connectors are modeled, and analyzed with the commercial software, ANSYS Version 8.1(Swanson, Inc., USA). The control group used implants instead of natural teeth. 21038 elements, 23544 nodes were used in experimental group and 107595 elements, 21963 nodes were used in control group, Stress distribution was evaluated under 150 N vertical load on 3 experimental conditions - between teeth and implants (Load case 1), posterior to implants (Load case 2), between natural teeth (Load case 3). Results: 1. In all load cases, higher von mises stress value was observed in the experimental group. 2. Maximum von miss stress observed in all load cases and all locations were as follows ; a. 929.44 Mpa in the experimental group, 640.044 Mpa in the control group in outer crown and connector - The experimental group showed 1.45 times high value compared with the control group. b. 145,051 Mpa in the experimental group, 142.338 Mpa in the control group in abutment - The experimental group showed 1.02times high value compared with the control group. c. 32.489 Mpa in the experimental group, 25.765 Mpa in the control group in alveolar bone - The experimental group showed 1.26times higher value compared with the control group. 3. All maximum von mises stress was observed in load case 2, and maxim von mises stress in alveolar bone was 32.489 Mpa at which implant failure cannot occur. 4. If maximum von mises stress is compared between two groups, the value of the experimental group is 1.02 times higher than the control group in abutment, 1.26 times higher than the control group in alveolar bone. Conclusion: If natural teeth and implants are connected with the konus telescopic denture, maximum stress will be similar in abutment, 1.26 times higher in alveolar bone than the control group. With this result, there may be possible to make to avoid konus telescopic dentures where natural teeth and implants exist together.

• 제어로봇시스템학회:학술대회논문집
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• 1993.10a
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• pp.168-172
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• 1993

As the worst-case analysis for interval plants, a conjecture whether the supremum of the integral of square error(ISE) is attained at the extreme point such as vertices, Kharitonov vertices, CB segment, and edges is suggested. We present a sufficient condition for which the worst performance index occurs at one ofvertices of uncertain parameter space. Numerical examples are also given.