• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2008.03a
• /
• pp.35-38
• /
• 2008

This paper develops an aero engine LPV mathematical model to exactly describe aero engine dynamic process characteristics, eliminate the effect of modeling error. Design FDF with eigenstructure assignment. The simulation results of turbofan engine control system sensor fault show that this method has good performance in focusing discrimination in fault signal with modeling eror, enhancing the robustness to unknown input, detecting accuracy is high and satisfiying real-time requirement.

• Proceedings of the KSR Conference
• /
• 2009.05b
• /
• pp.465-470
• /
• 2009

This paper discusses the numerical study on the dynamics of the high-speed EMU by developing the 34 degrees-of-freedom (DOF) lumped parameter model including the effect of the creepage. In order to reflect the creepage, the Kalker's wheel-rail contact theory is introduced in the proposed model. The dynamic analysis using $Matlab^{(R)}$ software is conducted, and its results are compared with those from ADAMS/Rail to investigate the validity of the proposed 34-DOF lumped parameter model. It is demonstrated that the results from the numerical study are similar to those from ADAMS/Rail. In addition, the critical design parameters of high-speed EMU are examined, and the design guidelines for reducing vibration and enhancing ride quality are proposed.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.18 no.10
• /
• pp.811-818
• /
• 2006

Mixing vanes have been installed in the space grid of nuclear fuel rod bundle to improve turbulent heat transfer. Split mixing vanes induce the vortex flow in the cooling water to swirl in sub-channel of fuel assembly. But, The swirling flow decays rapidly so that the heat transfer enhancing effect limited to short length after the mixing vane. In the present study, the large scale vortex flow (LSVF) is generated by rearranging the mixing vanes to the coordinated directions. This LSVF mixing vanes generate the most strong secondary flow vortices which maintain about $35D_h$ after the spacer grid. The streamwise vorticity generated by LSVF sustain two times more than that split mixing vane.

• Proceedings of the SAREK Conference
• /
• 2006.06a
• /
• pp.1144-1149
• /
• 2006

Electric power is generated by Seeback Effect if there is thermal difference in pettier module. Peltier module is composed by alumina, Bi-Te semiconductor and insulation (or air). If load is increased in pettier module, the alumina of module will be destroyed. One of the preventing method of module destruction is using damper between module and heat source. But the electric Power is dropped because of decrease of thermal difference, if thermal conductivity of damper was tourer than other thermoelectric materials. We design, Polymer Pad for enhancing thermoelectric porter. As the result of these experiment, Polymer Pad is more superior than the Rubber in the stability and thermal conduction.

• Nuclear Engineering and Technology
• /
• v.40 no.1
• /
• pp.1-8
• /
• 2008

One of the major current challenges to nuclear energy lies in its competitiveness. To stay competitive the industry needs to reduce maintenance and fuel cycle costs, while enhancing safety features. Extended burnup is one of the methods applied to meet these objectives However, there are a number of potential fuel failure causes related to increased burnup, as follows: l) Corrosion of zirconium alloy cladding and the water chemistry parameters that enhance corrosion; 2) Dimensional changes of zirconium alloy components, 3) Stresses that challenge zirconium alloy ductility and the effect of hydrogen (H) pickup and redistribution as it affects ductility, 4) Fuel rod internal pressure, 5) Pellet-cladding interactions (PCI) and 6) pellet-cladding mechanical interactions (PCMI). This paper discusses current and potential failure mechanisms of these failure mechanisms.

• International Journal of Advanced Culture Technology
• /
• v.9 no.3
• /
• pp.74-80
• /
• 2021

This study is to examine the determinants of tourists' revisit intention focusing on behavioral and psychological factors. Many studies have found physical conditions affecting tourists' intention to revisit. The study examines the determinants of tourist's revisit intention in terms of tourists' psychological and behavioral elements such as satisfaction and motivation. The data used for the statistical analyses were from a survey targeting people living in Daegu and Pusan metropolitan cities and some cities of Gyeongsangbuk-do and Gyeongsangnam-do provinces in Korea. The study employs regression analysis to investigate the effect of satisfaction and motivations on tourists' revisit intention. As the results of OLS regression analysis, satisfaction, push and pull motivation are predictors of tourists' revisit intention. It shows that tourists' psychological and behavioral factors have a significant impact on tourists' revisit intention. The study suggests the implications for enhancing tourists' revisit intention by motivating tourists' psychological and behavioral needs.

• International Journal of Internet, Broadcasting and Communication
• /
• v.13 no.2
• /
• pp.1-6
• /
• 2021

For competitive hotel business, the hotel must have a sound prediction capability to balance the demand and supply of hospitality products. To have a sound prediction capability in the hotel, it should be prepared to be equipped with a new technology such as quantum computing. The quantum computing is a brand new cutting-edge technology. It will change hotel business and even the whole world too. Therefore, we study the impact of quantum computing on supply chain management (SCM) and hotel performance. Toward the goal we have developed the research model including six constructs: quantum (computing) prediction, communication, supplier relationship, service quality, non-financial performance, and financial performance. The result of the study shows a significant influence of quantum (computing) prediction on hotel performance through the mediating role of SCM in the hotel. Quantum prediction is highly significant in enhancing the SCM in the hotel. However, the direct effect between the quantum prediction and hotel performance is not significant. The finding indicates that hotels which would install the quantum computing technology and utilize the quantum prediction could hugely benefit from the performance improvement.

• Journal of muscle and joint health
• /
• v.28 no.3
• /
• pp.275-282
• /
• 2021

Purpose: This descriptive study investigated the impacts of ego-resilience and academic stress on depression among nursing students. Methods: We recruited a total of 191 nursing students at C University located in C city through convenience sampling. Online data collection was conducted from August 22 to September 4, 2021. Data were analyzed using multiple regression analysis. Results: The results showed academic stress (β=.45, p<.001) and ego-resilience (β=-.14, p=.029) significantly affected on depression and explained 32.7% of depression of nursing student. Conclusion: To control nursing students' depression, it may need to develop programs enhancing ego-resilience and controlling academic stress and test the effect.

• Journal of Internet Computing and Services
• /
• v.19 no.6
• /
• pp.113-123
• /
• 2018

This study was conducted to empirically verify the effect of the technological entrepreneurship, network capability and technological innovation capability on the innovative performance of technology-based start-ups with the aim of determining the success factors of technology-based start-ups by defining the success of technology-based start-ups as the innovative performance through technology innovation activities. For the significance of this study, it suggested the importance of technology innovation as a survival strategy of technology-based start-ups, verified the dimensions, relationship and roles of technological entrepreneurship, network capability and technology innovation capability, thereby proving the theoretical expansion. This study has determined the success factors of technology-based start-ups and thereby suggested the strategic directions for enhancing the competitiveness of technology-based start-ups.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.45 no.5
• /
• pp.866-880
• /
• 2021

This study aimed to ex situ colorize laccase-entrapped bacterial cellulose (BC) with natural phenolic dyes, namely,madder, turmeric, and cochineal, and to determine the effect of laccase entrapment on the dyeability of BC using color strength (K/S) analysis. Results showed that laccase entrapment improved the dyeability of BC and that pre-entrapment was the most effective method, compared with meta-entrapment and post-entrapment methods. In addition, surface characterizations confirmed the successful entrapment of laccase inside the BC nanostructure and retention of the cellulosic and crystalline structures of BC. The washing durability test confirmed that the K/S value of BC had improved after laccase entrapment. Furthermore, laccase-entrapped BC colorized with cochineal dye had the highest washing durability due to the high molecular weight of cochineal dyerelative to the other dyes. This study suggests a novel method for enhancing the dyeability and washing durability of BC colorized ex situ with natural phenolic dyes by laccase entrapment.