• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.22 no.6
• /
• pp.1-16
• /
• 2023

Accurate traffic information prediction is considered to be one of the most important aspects of intelligent transport systems(ITS), as it can be used to guide users of transportation facilities to avoid congested routes. Various deep learning models have been developed for accurate traffic prediction. Recently, ensemble techniques have been utilized to combine the strengths and weaknesses of various models in various ways to improve prediction accuracy and stability. Therefore, in this study, we developed and evaluated a traffic information prediction model using various deep learning models, and evaluated the performance of the developed deep learning models as a stacking ensemble. The individual models showed error rates within 10% for traffic volume prediction and 3% for speed prediction. The ensemble model showed higher accuracy compared to other models when no cross-validation was performed, and when cross-validation was performed, it showed a uniform error rate in long-term forecasting.

• Journal of the Korean GEO-environmental Society
• /
• v.25 no.11
• /
• pp.45-53
• /
• 2024

In the current work, finite difference analysis was conducted by investigating the influence of dynamic analysis, considering effective stress, on the dynamic response of composite breakwaters. For comparison, the seismic behavior of breakwaters during the Kobe earthquake was analyzed, and performance-based seismic design was validated through centrifuge model test data, accompanied by a parametric study. The composite breakwaters damaged by the Kobe earthquake were verified through numerical analysis based on effective stress analysis, and validation of both centrifuge model tests and numerical analysis methods was conducted. The results of numerical analysis confirmed the seismic resistance based on the performance-based. And the results of analysis identified similar vertical displacement and liquefaction have confirmed through excess pore pressures. Also this study was conducted on the based on performance-based seismic deign, focusing on the results of acceleration, displacement, pore pressure, and liquefaction. Therefore the purpose of this study is to verify the results of pore pressure and liquefaction through the application and non-application of Finn model to compare the determination of liquefaction by the effective stress analysis.

• Journal of Energy Engineering
• /
• v.24 no.1
• /
• pp.149-163
• /
• 2015

In this study, we conducted study on the confirmation of thermal-hydraulic safety for Mast assembly with Computational Fluid Dynamics(CFD) analysis. Before performing the natural convection analysis for the Mast assembly by using CFD code, we validated the CFD code against two benchmark natural convection data for the evaluation of turbulence models and confirmation of its applicability to the natural convection flow. From the first benchmark test which was performed by Betts et al. in the simple rectangular channel, we selected standard k-omega turbulence model for natural convection. And then, calculation performance of CFD code was also investigated in the sub-channel of rod bundle by comparing with PNL(Pacific Northwest Laboratory) experimental data and prediction results by MATRA and Fluent 12.0 which were performed by Kwon et al.. Finally, we performed main natural convection analysis for fuel assembly inside the Mast assembly by using validated turbulence model. From the calculation, we observed stable natural circulation flow between the mast assembly and pool side and evaluated the thermal-hydraulic safety by calculating the departure from nucleate boiling ratio.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2006.05a
• /
• pp.688-692
• /
• 2006

산지 소하천 유역을 대상으로 물순환 과정을 규명하기란 대단히 어려운 실정이다. 1차적으로는 수문자료의 부재가 제일 크며, 자료가 있다 하더라도 홍수기 중심 및 단기간 자료의 축적에 불과하다. 이중 설마천 시험유역은 한국건설기술연구원의 11년간 운영경험을 바탕으로 비교적 장기간의 수문자료를 축적하고 있다. 최근 6년간은 신뢰할 만한 양질의 수문자료를 구축하였으며, 현재는 신뢰도의 완성을 높이는 연구가 활발히 진행 중에 있다. 설마천 시험유역의 유역의 물순환 구조는 자연계의 유입과 유출이 지배적이며, 이들의 수문성분을 규명하기 위해서는 각각의 수문성분들의 관측 및 해석이 필요하며, 각 수문성분들의 물수지 분석을 통하여 정량적인 합의 결과를 가시적으로 확보함이 매우 중요하다. 신뢰도와 정확성에 근거한 관측자료를 이용한 물수지 분석결과는 수문성분들의 총체적 표현이라 할 수 있는 모형(model)의 중요 입력자료이며, 모형의 분석결과를 검증할 수 있는 중요한 기준이 된다. 모형의 결과와의 비교 검토를 통해 산지 소하천 유역의 물순환 관계를 규명하는 기반을 확보하게 될 것이다. 본 연구에서는 신뢰성 있는 수문관측 자료를 이용하여 물수지 분석을 수행하였다. 물수지 분석의 대상유역인 설마천 시험유역의 신뢰할 만한 관측자료에는 강우량, 유출량, 지하수이용량이며, 증발산량 산정을 위한 기상관측 및 대형증발계를 통한 실제 증발량 관측은 이루어지나 유역을 대표하는 증발산량의 관측이 연속적으로 이루어지지 못하는 실정이다. 그러나, 설마천 시험유역은 소규모이며, 대체로 동질성 있는 유역이라고 가정하여 1개 기상관측소에서 운영하는 기상자료를 이용하여 증발산량을 산정하고 물수지에 적용하였다. 또한, 그 동안 관측하지 못했던 지하수위 관측을 실시함으로써 정확한 물순환 해석을 할 수 있는 기반을 확보 하였으며, 가용한 장 단기간의 관측자료와 물수지 분석 연산식의 추정치를 바탕으로 관측자료에 의한 물수지 분석을 수행하였다. 분석 결과로 산지 소하천 유역인 설마천 시험유역의 각 수문요소의 물이동간의 정량적인 값을 알 수가 있었으며, 앞으로 추가적이고 지속적인 수문모니터링이 운영되고 물순환 해석 모형에 의한 검증이 수행된다면 정량적인 물순환 관계를 규명할 수 있을 뿐만 아니라 이와 관련된 수문요소기술을 확보할 수 있을 것이다.

• Journal of Korean Society of Steel Construction
• /
• v.18 no.5
• /
• pp.655-664
• /
• 2006

The purpose of thisanalytical study of an iTECH composite beam subjected to fire conditions is to determine the beam's fire resistance performance using its load ratio and fire protection as parameters. A composite structural system is expected to have a safer and more economical fire safety design than a mere collection of isolated members.heat transfer analysis was performed on the basis of the finite element program ANSYS 10.0 using an ISO834 standard fire, following the main guidelines proposed by EC1 Part 2.2 and EC4 Part 1.2. To validate the analytical simulation of the iTECH composite beam, comparison of the experimental tests was proposed.

• Culinary science and hospitality research
• /
• v.20 no.4
• /
• pp.239-252
• /
• 2014

This study aimed to identify the influence of a nutrition teacher's servant leadership on cooks' empowerment and organizational commitment in school organization. For this purpose, this study selected 288 cooks working in elementary, middle and high schools located in Daegu city, and conducted a survey toward them. The collected data were analyzed with the frequency analysis, the reliability verification, the correlation test, and the multi-regression analysis. As the results testing the hypotheses, the following 3 hypotheses were chosen as valid ones. First hypothesis: A nutrition teacher's servant leadership will positively(+) influence on cooks' empowerment. Second hypothesis: A nutrition teacher's servant leadership will positively(+) influence on cooks' organizational commitment. Third hypothesis: A cook's servant empowerment will positively(+) influence on his/her organizational commitment. Therefore, nutrition teachers should exercise their servant leadership so that cooks can be responsible for the quality of school meals and perform their work on the basis of autonomy and creativity. In order to perform the role of a servant leader, nutrition teachers will need to continually get various educational, training programs for enhancing their servant leadership.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2007.05a
• /
• pp.1493-1497
• /
• 2007

산지 소하천 유역을 대상으로 물순환 과정을 규명하기란 대단히 어려운 실정이다. 1차적으로는 수문자료의 부재가 제일 크며, 자료가 있다 하더라도 홍수기 중심 및 단기간 자료의 축적에 불과하다. 이중 설마천 시험유역은 한국건설기술연구원의 12년간 운영경험을 바탕으로 비교적 장기간의 수문자료를 축적하고 있다. 최근 7년간은 신뢰할 만한 양질의 수문자료를 구축하였으며, 현재는 신뢰도의 완성을 높이는 연구가 활발히 진행 중에 있다. 설마천 시험유역의 유역의 물순환 구조는 자연계의 유입과 유출이 지배적이며, 이들의 수문성분을 규명하기 위해서는 각각의 수문성분들의 관측 및 해석이 필요하며, 각 수문성분들의 물수지 분석을 통하여 정량적인 합의 결과를 가시적으로 확보함이 매우 중요하다. 신뢰도와 정확성에 근거한 관측자료를 이용한 물수지 분석결과는 수문성분들의 총체적 표현이라 할 수 있는 모형(model)의 중요 입력자료이며, 모형의 분석결과를 검증할 수 있는 중요한 기준이 된다. 모형의 결과와의 비교 검토를 통해 산지 소하천 유역의 물순환 관계를 규명하는 기반을 확보하게 될 것이다. 본 연구에서는 신뢰성 있는 수문관측 자료를 이용하여 물수지 분석을 수행하였다. 물수지 분석의 대상유역인 설마천 시험유역의 신뢰할 만한 관측자료에는 강우량, 유출량, 지하수이용량이며, 증발산량 산정을 위한 기상관측 및 대형증발계를 통한 실제 증발량 관측은 이루어지나 유역을 대표하는 증발산량의 관측이 연속적으로 이루어지지 못하는 실정이다. 그러나, 설마천 시험유역은 소규모이며, 대체로 동질성 있는 유역이라고 가정하여 1개 기상관측소에서 운영하는 기상자료를 이용하여 증발산량을 산정하고 물수지에 적용하였다. 또한, 그 동안 관측하지 못했던 지하수위 관측을 실시함으로써 정확한 물순환 해석을 할 수 있는 기반을 확보 하였으며, 가용한 장 단기간의 관측자료와 물수지 분석 연산식의 추정치를 바탕으로 관측자료에 의한 물수지 분석을 수행하였다. 분석 결과로 산지 소하천 유역인 설마천 시험유역의 각 수문요소의 물이동간의 정량적인 값을 알 수가 있었으며, 앞으로 추가적이고 지속적인 수문모니터링이 운영되고 물순환 해석 모형에 의한 검증이 수행된다면 정량적인 물순환 관계를 규명할 수 있을 뿐만 아니라 이와 관련된 수문요소기술을 확보할 수 있을 것이다.

• Journal of the Korean Society for Library and Information Science
• /
• v.54 no.3
• /
• pp.209-236
• /
• 2020

This study describes a set of user experience indicators developed for the evaluation of knowledge and information resource systems. The user experience perspectives had emerged as a new analysis standard in the field of information media and information service research. The study included a survey conducted to verify the derived experience factors and developed them as indicators. The survey data was gathered from 158 participants in the preliminary and 480 participants in the main study. The applied analysis techniques were descriptive statistics, the exploratory factor analysis, the confirmatory factor analysis, the correlation analysis, and the path analysis. The results introduced seven user experience factors, 37 detailed user experience factors, and 105 system perception factors as the final user experience indicators. The developed and verified indicators should measure the degree of user experience perceived by users of the knowledge and information resource system and conduct effective evaluations that reflect correlation rather than a simple comparison of each experience factor.

• The Journal of the Convergence on Culture Technology
• /
• v.6 no.2
• /
• pp.139-143
• /
• 2020

Purpose: This study was conducted to examine the effects of a strength coaching program on nursing students' clinical competence, self esteem, and practice satisfaction. The study was designed using a nonequivalent control group pretest-post test design, and data were collected between January 7 and February 1, 2019. The participants consisted of 41, 3-year nursing students in G City who were assigned to an experimental group (n=21) or a control group (n=20). The data were analyzed using descriptive analysis, a t-test, χ² test, and paired t-test with the SPSS/WIN 21.0 program. After receiving the strength coaching program, a difference was observed in self esteem(t=5.53, p<0.038), and practice satisfaction (t=7.66, p<0.019) of the experimental group. The results of this study indicate that the strength coaching program was effective at increasing self esteem and practice satisfaction in nursing students.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.9 no.6
• /
• pp.681-687
• /
• 2014

Nuclear industries have faced unfavorable circumstances such as an obsolescence of the instrumentation and control system, and therefore nuclear society is striving to resolve this issue fundamentally. IEC and IAEA judge that FPGA technology is a good replacement for Programmable Logic Controller (PLC) of Nuclear Instrumentation and Control System. FPGAs are currently highlighted as an alternative means for obsolete control systems. Because the main function inside an FPGA is initially developed as software, good software quality can impact the reliability of an FPGA-based controller. Therefore, it is necessary to establish a software development aspect strategy that enhances the reliability of an FPGA-based controller. In terms of software development, HDL-Programmed Device (HPD) Development Life Cycle is applied into FPGA-based Controller. The burn-in test and environmental(temperature) test should be performed in order to apply into nuclear instrumentation and control system. Therefore it is ensured that the developed FPGA-based controller are normally operated for 352 hours and 92 hours in test chamber of Korea Institute of Machinery and Materials (KIMM).