• Journal of the Earthquake Engineering Society of Korea
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• v.9 no.4 s.44
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• pp.55-66
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• 2005

The effectiveness of fuzzy supervisory control technique for the control of seismic responses of smart base isolation system is investigated in this study. To this end, first generation base isolated building benchmark problem is employed for the numerical simulation. The benchmark structure under consideration is an eight-story base isolated building having irregular plan and is equipped with low-damping elastometric bearings and magnetorheological (MR) dampers for seismic protection. Lower level fuzzy logic controllers (FLC) for far-fault or near-fault earthquakes are developed in order to effectively control base isolated building using multi-objective genetic algorithm. Four objectives, i.e. reduction of peak structural acceleration, peak base drift, RMS structural acceleration and RMS base drift, are used in multi-objective optimization process. When earthquakes are applied to benchmark building, each of low level FLCs provides different command voltage and supervisory fuzzy controller combines two command voltages io one based on fuzzy inference system in real time. Results from the numerical simulations demonstrate that base drift as well as superstructure responses can be effectively reduced using the proposed supervisory fuzzy control technique.

• Smart Structures and Systems
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• v.10 no.3
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• pp.271-298
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• 2012

Researchers have made significant progress in recent years towards realizing effective structural health monitoring (SHM) utilizing wireless smart sensor networks (WSSNs). These efforts have focused on improving the performance and robustness of such networks to achieve high quality data acquisition and distributed, in-network processing. One of the primary challenges still facing the use of smart sensors for long-term monitoring deployments is their limited power resources. Periodically accessing the sensor nodes to change batteries is not feasible or economical in many deployment cases. While energy harvesting techniques show promise for prolonging unattended network life, low power design and operation are still critically important. This research presents the WiSeMote: a new, fully integrated ultra-low power wireless smart sensor node and a flexible base station, both designed for long-term SHM deployments. The power consumption of the sensor nodes and base station has been minimized through careful hardware selection and the implementation of power-aware network software, without sacrificing flexibility and functionality.

• International Journal of Internet, Broadcasting and Communication
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• v.5 no.2
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• pp.15-17
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• 2013

The web service companies develop the App support technique of the HTML5 base in the smart media system and smart TV competitively while the Web platform of the HTML5 base is legislated with the next generation national standard. It is essential to the web kernel, which is the common library of the operating system including the file, window, resource and network management is provided in order to support the various app developments of the HTML5 base effectually. Additionally, the web application program can support UI/UX function of the desktop user using the web browser and JavaScript drive and administration, window management function, and etc. is needed.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2005.03a
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• pp.544-551
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• 2005

This paper investigates the effectiveness of the MR damper-based control systems for seismic protection of base isolated building sturcutres employing some semiactive control algorithms, such as the modified clipped-optimal control, the maximum energy dissipation, and the modulated homogeneous friction, by examining the Phase I smart base isolated benchmark building problem. The results of the numerical simulations showed that most of the control systems considered herein could be beneficial in reducing seismic responses, especially base displacement or isolator deformation, of base isolated building structures. It is also verified that another version of the modified clipped-optimal control algorithm proposed in this study and the modulated homogeneous friction algorithm are more effective than other semiactive control algorithms.

• Journal of Korean Association for Spatial Structures
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• v.12 no.2
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• pp.99-108
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• 2012

Microvibration problem of high-technology facilities, such as semi-conductor plants and TFT-LCD plants, has been considered as important factors that affects the performance of products and thus it is regarded as important in facilities with high precision equipments. In this paper, various base isolation control systems are used to investigate their microvibration control performance. To this end, train-induced ground acceleration is used for time history analysis and three-story example building structure is employed. Microvibration control performance of passive and smart base isolation systems have been investigated in this study. Based on numerical simulation results, it has been verified that smart base isolation system can control microvibration of a high-technology facility subjected to train-induced excitation.

• Smart Structures and Systems
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• v.23 no.1
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• pp.91-106
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• 2019

Adopting sloped rolling-type isolation devices underneath a raised floor system has been proved as one of the most effective approaches to mitigate seismic responses of the protected equipment installed above. However, pounding against surrounding walls or other obstructions may occur if such a base-isolated raised floor system is subjected to long-period excitation, leading to adverse effects or even more severe damage. In this study, real-time hybrid simulation (RTHS) is adopted to assess the control performance of a smart base-isolated raised floor system as it is an efficient and cost-effective experimental method. It is composed of multiple sloped rolling-type isolation devices, a rigid steel platen, four magnetorheological (MR) dampers, and protected high-tech equipment. One of the MR dampers is physically tested in the laboratory while the remainders are numerically simulated. In order to consider the effect of input excitation characteristics on the isolation performance, the smart base-isolated raised floor system is assumed to be located at the roof of a building and the ground level. Four control algorithms are designed for the MR dampers including passive-on, switching, modified switching, and fuzzy logic control. Six artificial spectrum-compatible input excitations and three slope angles of the isolation devices are considered in the RTHS. Experimental results demonstrate that the incorporation of semi-active control into a base-isolated raised floor system is effective and feasible in practice for high-tech industry.

• Review of Korea Contents Association
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• v.18 no.2
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• pp.12-17
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• 2020

• Journal of Korean Association for Spatial Structures
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• v.12 no.4
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• pp.71-80
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• 2012

Because a smart isolation system cannot be used as a base isolation system for tall buildings, top-story or mid-story isolation systems are required. In this study, adaptability of a smart top-story isolation system for reduction of seismic responses of tall buildings in regions of low-to-moderate seismicity has been investigated. To this end, 20-story example building structure was selected and an MR damper and low damping elastomeric bearings were used to compose a smart base isolation system. Artificial earthquakes generated based on design spectrum of low-to-moderate seismicity regions are used for structural analyses. Based on numerical simulation results, it has been shown that a smart top-story isolation system can effectively reduce both structural responses and isolation story drifts of the building structure in low-to-moderate seismicity regions in comparison with a passive top-story isolation system.

• International Journal of Internet, Broadcasting and Communication
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• v.13 no.2
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• pp.179-186
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• 2021

We have been developed the smart tourism app and the Instagram and YouTube contents to provide personalized tourism information and travel product information to individual tourists. In this paper, we develop a rule-based smart tourism chatbot with the khaiii (Kakao Hangul Analyzer III) morphological analyzer and Neo4J graph database. In the proposed chatbot system, we use a morpheme analyzer, a proper noun dictionary including tourist destination names, and a general noun dictionary including containing frequently used words in tourist information search to understand the intention of the user's question. The tourism knowledge base built using the Neo4J graph database provides adequate answers to tourists' questions. In this paper, the nodes of Neo4J are Area based on tourist destination address, Contents with property of tourist information, and Service including service attribute data frequently used for search. A Neo4J query is created based on the result of analyzing the intention of a tourist's question with the property of nodes and relationships in Neo4J database. An answer to the question is made by searching in the tourism knowledge base. In this paper, we create the tourism knowledge base using more than 1300 Jeju tourism information used in the smart tourism app. We plan to develop a multilingual smart tour chatbot using the named entity recognition (NER), intention classification using conditional random field(CRF), and transfer learning using the pretrained language models.

• Journal of the Korean Society of Clothing and Textiles
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• v.41 no.5
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• pp.872-882
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• 2017

There are no specific guidelines on how to control the heat input for the heat generating smart base layer. This study investigated the mode of actuating heat pad attached to the base layer by performing a human wear test in a cold environment. Subjects participating in the test wore T-shirts, jumper and pants on the base layer with heating pads. Skin temperature, total time of heating and the number of switching for the heating mode were observed as the subject controlled the heating mode voluntarily. The comfortable range of skin temperature on the abdomen was larger than on the lower back. The subject felt hot and turned off the switch when the mean skin temperature of the abdomen was $48.8^{\circ}C$ and the lower back was $40.1^{\circ}C$. The total heating time and the number of actuating switching were larger for women than men. The voluntary action of heating for men with high cold sensitivity was significantly different from men with low cold sensitivity. Therefore, it is necessary (depending on gender and cold sensitivity) to set the heating mode differently for the automatic heat control of a future smart base layer.