• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.56-59
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• 1997

The recent machine tools are requested so high-quality processing and productivity increasing. Therefore it is so necessary to develop technology for high-speed and high-precision. This thesis touches on the development of high speed and intellectual line center. At first, the line center is necessary that strong structure, compact structure an light weight design for high-speed processing and transfer. So. It is necessary that examination of new materials and structures for light-weight and control devices for precision processing. So. it si going to make mention of the process of 1st model production for the above-mentioned base on test model production and evaluation.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.107-112
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• 2003

The recent machine tools are requested so high-quality processing and productivity increasing. Therefore, it is so necessary to develop technology for high-speed and high-precision. This thesis touches on the development of high speed and intellectual line center. At first, the line center is necessary that strong structure, compact structure and light weight design for high-speed processing and transfer. So, it is necessary that examination of new materials and structures for light-weight and control devices for precision processing. So, it is going to make mention of the process of 1st model production for the above-mentioned based on test model production and evaluation.

• Journal of the Korean Society of Safety
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• v.30 no.2
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• pp.27-34
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• 2015

Nowadays, remodeling cases for some apartment like Hyundai through the support of government are reported. Conventionally, balcony and aisle are extended for additional private area or balcony which is supported by new frame is extended. In extension work at site, dowel bar is conventionally inserted in old concrete slab for connection with old and new slab, however, an examination for structural safety is rarely performed prior to construction, if ever, vertical load is only considered for structural analysis. When conventionally connected structures are exposed to earthquake, the old and new structures have individual earthquake behavior with different mode, which may lead the elimination of resistance to earthquake in new structures. As of this reason, new detailing connection system which can have light weight and sufficient ductility performance is developed for application to domestic extension works. Additionally, user manual and specification are also developed for fertilization of application for the developed technology.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1998.04a
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• pp.365-372
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• 1998

Recently, constructions of large and slender structures have been increased owing to the advancement of the structural technologies and that of the new light-weight and high-strength construction materials. Consequently, vibration problems of those slender structures have become a new issue in the area of structural engineering. Active control for those structures is the method that keeps the structures safe from the external loads, especially dynamic loads, by enforcing active forces derived from control devices. In this paper, a procedure for the instantaneous optimal control for structural vibration is presented. Numerical method and experiment are performed for evaluating the effectiveness of active control for reducing vibration of structures.

• Journal of KSNVE
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• v.10 no.1
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• pp.82-96
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• 2000

The purpose of this study is to figure out the relationship between the mini-laboratory and the reverberation room for the domestic floor structures which are practically constructed in apartment houses. For this purpose, seven specimen which were varied in structures and thicknesses were tested in Chonnam National University reverberation room and in the artificial mini-laboratory which is the $\farc{1}{3}$ scale model of the former. From the result of this study, it was proved that there is a good correlation between the mini-laboratory and the reverberation room for the apartment floor structures as well as floorcovering PVC. The result of this study could save the labor and the time, etc.

• Steel and Composite Structures
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• v.44 no.2
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• pp.211-224
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• 2022

Multi-objective optimization was conducted to obtain the optimal configuration of a composite sandwich structure with honeycomb-foam hybrid core subjected to underwater shock waves, which can fulfill the demand for light weight and energy efficient design of structures against underwater blast. Effects of structural parameters on the dynamic response of the sandwich structures subjected to underwater shock waves were analyzed numerically, from which the correlations of different parameters to the dynamic response were determined. Multi-objective optimization of the structure subjected to underwater shock waves of which the initial pressure is 30 MPa was conducted based on surrogate modelling method and genetic algorithm. Moreover, optimization results of the sandwich structure subjected to underwater shock waves with different initial pressures were compared. The research can guide the optimal design of composite sandwich structures subjected to underwater shock waves.

• International conference on construction engineering and project management
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• 2011.02a
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• pp.304-310
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• 2011

The populations of major cities in Australia are increasing rapidly and facing an acute housing shortage. Traditional apartment procurement techniques involve lengthy lead-times and factory-based, or offsite manufactured (OSM) multi-storey apartment buildings may offer the opportunity to help fulfill the need by significantly reducing build times. Other advantages of OSM may include superior quality, low weight ratios, economies of scale achieved through repetition of prefabricated units, use on infill sites, sustainable design standards and better occupational health and safety. There are also positive labour and training implications, which may help to alleviate an industry-wide shortage of skills through use of semi-skilled labour. Previous uncertainties about the adoption of offsite due to the high capital costs and perception issues were generally based on pre-cast concrete structures, which are quite a different building type in terms of flexibility, construction, delivery and finishes. Identification of drivers and constraints assists in the determination of current industry status, allows for a benchmark to be established and future opportunities and directions for OSM to be determined.

• Journal of the Korean housing association
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• v.13 no.5
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• pp.9-20
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• 2002

The purpose of this study are to evaluate the dwelling quality of rural houses constructed with industrialized wall structures(ALC; Autoclaved Light weight Concrete, SRC; Steel Fiber Reinforced Concrete, ST'L; Steel Framed Insulating Panel), and to establish a method of dwelling quality evaluation. The questionnaire survey by mail was done, for investigating the residents' responses to indoor environment, durability, and economic aspect. The respondents are 118 residents living in rural houses constructed with industrialized wall structures. Physical elements of indoor environment(temperature, humidity, air quality, and noise level) were measured in three sample houses, which were selected considering of architectural characteristics. The findings are as follows; 1) As a result of questionnaire survey, residents' responses to dwelling quality are generally positive. 2) As a result of measurement, indoor environments of sample houses are in relatively comfortable condition. 3) As a summary of research, ALC and ST'L are evaluated as recommendable structures for a rural house.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1998.03a
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• pp.71-74
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• 1998

In recent years, advances in construction techniques and materials have given rese to flexible light-weight structures like high-rise buildings and long-span bridges. Because these structures extremely susceptible to environmental loads, such as earthquakes and strong winds, these random loadings usually produce large deflection and acceleration on these structures. Vibration control system of structures are becoming an integral part of the structural system of the next generation of tall building. The proposed control system is applied to single degree of structure with mass damping and compared with conventional PID and neural network PID control system.

• Journal of Aerospace System Engineering
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• v.15 no.2
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• pp.16-25
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• 2021

Reliability of fatigue strength on Aircraft Composites(GFRP) Structures was assessed in this paper. Fatigue strength of GFRP was used through the existing fatigue test data with Monte Carlo method. The S_a-N_f curve of composites fatigue strength was assumed as normal distribution and reliability was analyzed using SSIT model. Fatigue stress was designed IAW ASTM F3114-15 with special safety factor of S_sf=1.2~2.0. Reliability was calculated by analytic method and FORM. Sensitivity for the effect of mean and standard deviation of fatigue strength as well as fatigue stability was evaluated. This result can be usefully applied to reliability and fatigue design for composite structures of light weight aircraft.