• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.3 no.4
• /
• pp.133-142
• /
• 1983

A new dynamic pile-driving formula derived by the writer, in which the mechanics of stress waves and the effect of residual stresses were considered for more accurate prediction of the load carrying capacity of piles, was compared with other representative formulas through statistical analysis using the load test results. As the result, the new formula was estimated as highly accurate and reliable, with its safety factor less than 3.

• Journal of the Korean Society of Combustion
• /
• v.19 no.2
• /
• pp.28-36
• /
• 2014

Bio fuel oil combustion experiments were successfully demonstrated at the 75 MWe oil-fired power plant without major equipment retrofit and 100% bio-fuel oil combustion was possible without big problems. The experimental data error correction was conducted and numerical model-based analysis technique was applied for the evaluation of the results. Incase of bio fuel oil combustion, heat absorption of radiative heat transfer section was reduced while convection section has opposite trend. The furnace exit gas temperature tends to rise slightly. Environment emissions such as NOx and SOx concentrations showed a tendency to decrease during the bio fuel oil combustion period. On the other hand, boiler efficiency was slightly underestimated.

• International Journal of Safety
• /
• v.2 no.1
• /
• pp.23-27
• /
• 2003

Recently, continuous fiber reinforced ceramic composite(CFCC) has attracted attention to a number of engineers because of its significant benefit for several industrial area. This work was conducted to provide a basic characteristic of CFCC for tensile loading condition. The numerical analysis by general purpose finite element program was accomplished and compared with an experimental tensile test. The stress strain curves were expressed well by the numerical analysis and the first matrix cracking stress was in accordance with that of the experimental result. Moreover, fracture pattern was shown by kill command graphically.

• Journal of the Korean Society for Railway
• /
• v.3 no.4
• /
• pp.203-212
• /
• 2000

In order to evaluate the stability of railway embankment under rainfall, explanatory variables and subordinate variables were selected for multivariate analysis. Furthermore the site which had occurred failure due to rainfall was investigated, and by executing multivariate analysis for 121 cases, critical rainfall was defined by the case that had high value of correlation factor The maximum hourly rainfall during 24 hours before failure caused the collapse of railway embankment and could be used estimate the stability of railway embankment. From the result of application to a collapse example, the evaluaton method by critical rainfall curve is satisfactory.

• Proceedings of the KSR Conference
• /
• 2004.06a
• /
• pp.675-678
• /
• 2004

Comparative analysis it did the interior noise of the KTX vehicle and the P-P Semaeul vehicle from the conventional line Homan Seodaejeon-Hanam section from the research which it sees. The test result KTX vehicle appeared when the P-P Semaeul vehicle compared to 20 - 25 KM/H speed up operating commerce operation speed even, the standard values 66 dBA the lowers 55 - 62 dBA. P-P Semaeul vehicle interior noise of the identical test section 63 dBA it will compare and there is a possibility the KTX vehicle knowing from the existing line operating hour interior noise.

• Proceedings of the KWS Conference
• /
• 2006.10a
• /
• pp.178-180
• /
• 2006

The present article aims to develop a numerical method for numerical analysis of fusible filler behavior for self-interconnection process. The CIP(Cubic Interpolated Propagation) method is used for determination of interfaces and the CSF(Continuum Surface Force) model is adopted for evaluation of curvature. To validate these models, first, the present study performs the numerical simulation for a droplet formation and it simulates the interactions among fusible fillers inside resin under the operating condition. As a result, similar tendency is found compared to the experimental observation. This study would be a first step towards finding the optimum condition for self-interconnection process.

• The Journal of Information Systems
• /
• v.25 no.3
• /
• pp.217-245
• /
• 2016

Purpose With the increasing number of foreign travelers visiting Korea, it is a heavy question to evaluate service quality of typical domestic hotel companies. Our research aims to evaluate service quality of domestic hotels in Korea from the perspective of foreign travelers in order to provide the quality improvements that call attention for the hotel management. Design/Methodology/Approach In this paper, topics of sentiment followed Lodging Quality Index(LQI) dimensions classifying lodging service quality appropriately. Also, we employed word2vec algorithm which calculates similarity and affinity among the vocabularies accurately. To calculate sentiment of each dimension, we adopted scores from SentiWordNet. Findings From the result, we found the number of foreign travelers particularly satisfied with cleanliness, politeness, and problem solving skills. In contrast, it has also been found out that both promptness of services and efficiency of communication do not fulfill the requirements of travelers.

• Journal of the Korea Society of Computer and Information
• /
• v.23 no.7
• /
• pp.121-129
• /
• 2018

Since 2005, POSCO has been conducting continuous innovation activities using its own innovation methodology, QSS + (Quick Six Sigma Plus). Recently, the effectiveness of QSS + has been decreased owing to the different needs and purposes for each group. The purpose of this study is to compare the weights of the QSS + factors using AHP analysis. QSS + factors consist of two levels. The high level consists of 7 items : 'Master Plan, Waste Zero Activity, Daily Improvement Activity, Talent Development, Project Activity, Initiative/Encouragement activity'. The low level consists of 3 items '5S, My Machine, My M&S' for Daily Improvement Activity. As a result, we found that there was a difference between the weights of the four groups. We suggest the effective QSS + directions to improve the quality of POSCO.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2010.03a
• /
• pp.1051-1060
• /
• 2010

In this study, the pressuremeter test (PMT) and the standard penetration test (SPT) were performed on the lateral pile loading tests site to evaluate the coefficient of subgrade reaction, which is used for load-deformation behavior analysis of laterally loaded piles by elastic subgrade reaction method. As a result, widely used empirical formulas of the coefficient of subgrade reaction by N values of SPT is evaluated conservatively lateral behavior of piles. While the method of directly used PMT results and evaluation method of the coefficient of subgrade reaction considering deformation moduli of soil and a pile diameter that is able to estimate very similar to actual load-deformation behavior of laterally loaded piles in deformation range of 0.5%-1.0% of a pile diameter.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.10 no.5
• /
• pp.38-43
• /
• 2011

This study was carried out to evaluate the structural stability of hybrid type fan heater. The evaluation of structural safety of hybrid fan heater was conducted by using Ansys Workbench and CFX-11 under the design condition. The hybrid fan heater was operated by heat transfer for heat source supplied from electric heater and combustion gas. According to result of structural analysis, the maximum equivalent stress of hybrid fan heater was 150MPa when the temperature of heat transfer fluids was $150^{\circ}C$. It was found that the hybrid fan was structurally safe because the value of maximum equivalent stress was smaller than that of yield stress of the material.