• KSCE Journal of Civil and Environmental Engineering Research
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• v.39 no.3
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• pp.441-449
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• 2019

Recently, interest in the seismic safety of structures is rising in South Korea due to the occurrences of earthquakes of 5.0 or greater magnitudes such as Gyeongju earthquake (September 2016) and Pohang earthquake (November 2017). In particular, the importance of living facilities that cause human injuries and property losses is more emphasized. Representative living facilities include gas and oil storage facilities and water tanks. In this study, the seismic performance of liquid storage tanks is improved by applying the lead rubber bearing, which is a seismic isolation method. The lead rubber bearing was designed considering the foundation of liquid storage tanks, and the general properties of the lead rubber bearing were verified through compression and shear tests using fabricated specimens. Furthermore, the behaviors of liquid storage tanks according to seismic and non-seismic isolations were analyzed through durability test, shaking table test and finite element analysis using ANSYS.

• 한국정책학회보
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• v.21 no.1
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• pp.337-361
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• 2012

This study is conducted to provide empirical evidences which support that the problems of social isolation and loneliness of elderly can be alleviated by intervening the inter-generational relationship of the elderly by means of active ageing policy. The major empirical challenge to address this question is the possibility of selection bias caused by reversed causal relationship. To address this challenge, I constructed comparison group with 'Eligible Non-Participants' (ENP), and used instrumental variable method to estimate the empirical model. My findings indicate that inter-generational relationship, both in the aspects of economical solidarity and associational solidarity, is significantly improved as time use pattern of the elderly becomes more active. The improvement effect is intensively observed for the group of elderly who do not live with their adult children. The important policy implication of these findings is that the improvement of inter-generational relationship can be added as a new benefit of active ageing policy.

• Korean Journal of Social Welfare Studies
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• v.44 no.2
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• pp.409-436
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• 2013

The purpose of this study is to examine the residential institutions for the disabled in Korea on the base of welfare rights, and to propose some actual ways for improvement. For this, we analyzed the attributes of the residential institutions for the disabled in Korea. The results shows that the residential institutions for the disabled in Korea are characterized by massiveness, isolation, inequality in power, and no choice. For improvement we suggested that the residential institutions for the disabled should be run by the principles of supplement, normalization, inter-reliance, and individualization. In order to achieve these goals, the government has to invest the needs for de-institutionalization of the users, run the institutions on the smaller scale and replace them in communities, and systemize the person-centered support and service provision processes. In addition to them, the managers of the institutions should try to socialize the institutions, and to increase the participation of the users in management.

• KIEE International Transactions on Electrophysics and Applications
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• v.4C no.5
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• pp.241-246
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• 2004

In this paper, we present a novel integrated cell processor to handle individual embryos. Its functions are composed of transporting, isolation, orientation, and immobilization of cells. These functions are essential for biomanipulation of single cells, and have been typically carried out by a proficient operator. The purpose of this study is the automation of these functions for safe and effective cell manipulation using a MEMS based cell processor. This device is realized with a relatively simple design and fabrication process. Experimental results indicate that it can act as an efficient substitute for essential but very tiresome and repetitive manual work while contributing significantly to the improvement of speed and success rate of operation by facilitating cell manipulation. The cell viability test for the device is studied through the distribution of mitochondria in mice embryos and cultivation of cells for 86h.

• Smart Structures and Systems
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• v.16 no.4
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• pp.725-742
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• 2015

Tuned mass dampers (TMD) are devices employed in vibration control since the beginning of the twentieth century. However, their implementation for controlling the seismic response in civil structures is more recent. While the efficiency of TMD on structures under far-field earthquakes has been demonstrated, the convenience of its employment against near-fault earthquakes is still under discussion. In this context, the study of this type of device is raised, not as an alternative to the seismic isolation, which is clearly a better choice for new buildings, but rather as an improvement in the structural safety of existing buildings. Seismic records with an impulsive character have been registered in the vicinity of faults that cause seismic events. In this paper, the ability of TMD to control the response of structures that experience inelastic deformations and eventually reach collapse subject to the action of such earthquakes is studied. The results of a series of nonlinear dynamic analyses are presented. These analyses are performed on a numerical model of a structure under the action of near-fault earthquakes. The structure analyzed in this study is a steel frame which behaves as a single degree of freedom (SDOF) system. TMD with different mass values are added on the numerical model of the structure, and the TMD performance is evaluated by comparing the response of the structure with and without the control device.

• Journal of the Korean Society for Library and Information Science
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• v.47 no.2
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• pp.5-24
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• 2013

Many students with disabilities at the university face difficulties in educational inequity, cultural isolation, information illiteracy, and discrimination in the broad range of campus activities. The biggest barrier is the lack or difficulty of access to knowledge and information needed for learning. Libraries, therefore, must not discriminate against students with disabilities and should ensure equal access to and use of information resources and services. This paper analyzed the satisfaction and requirements on facility and space services, direct and indirect services, total library service of students with disabilities based on the results of the survey and interview. This paper suggested ways to improve service satisfaction of students with disabilities in a university library.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2008.11a
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• pp.237-242
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• 2008

This paper presents vibration control of an active hybrid engine mount featuring magneto-rheological (MR) fluid and a piezostack actuator. On the basis of the conventional passive rubber mount, MR fluid is adopted to improve isolation performance at resonant frequencies, whereas the piezostack actuator is adopted for performance improvement at non-resonant frequencies, especially at high frequencies. Based on some particular practical requirements of engine mounts, the proposed mount is designed and manufactured. The characteristics of rubber element, piezostack actuator and MR fluid are verified for system analysis and controller synthesis. The model of the proposed mount with a supported mass (engine) is established. In this work, a sliding mode controller is synthesized for the mount system to reduce vibrations transmitted from the engine in a wide frequency range. Computer simulations are performed to evaluate the performances of the proposed active engine mount in time and frequency domains.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.30 no.3
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• pp.170-174
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• 2017

In 3 electrode reflective displays using a plastic substrate, unstable packaging induces particle clumping and optical degradation due to external air inflow and electronic ink evaporation. In this work, we fabricate 3 electrode electronic paper using glass wafer, ITO/plastic film, and ITO/glass/gas barrier film as an upper substrate after injecting electronic ink onto the lower substrate. Then, we studied its properties. After operating under stress conditions for 336 hours at $85^{\circ}C$ and 75% humidity, the reflectivity of driven e-paper panels with white color was 25.5% for the panels using glass wafer, 22.5% for plastic film including a gas barrier layer, and 16% for plastic film only. From these optical properties, we conclude that gas barrier film improves upper film isolation as a desirable packaging method.

• Transactions of the Korean Society of Automotive Engineers
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• v.2 no.3
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• pp.21-32
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• 1994

The Problem of mechanical vibration is investigated for an automotive exhaust system. The vibrational reduction effect is systematically evaluated according to the attachment of the exhaust system. Moreover, the optimal attachment position of bellows is determined from the viewpoint of vibration isolation. The structure is analysed by the finite element technique where the geometry, the mass, the stiffness and the damping properties of the exhaust pipe are modeled. The validity of the developed model is verified by comparing with the experimental results. An optimization is carried out by the quadratic approximation algorithm. The reaction transferred to an automobile body by the hanger is considered ad the objective function. It is shown that the exhaust system which has the bellows at the optimal position is more effective for the vibrational characteristics than the others. It is also proved that this analytical method is quite useful in the design stage of the exhaust system.

• Microbiology and Biotechnology Letters
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• v.16 no.3
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• pp.182-186
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• 1988

The possibility of strain improvement of cellulolytic fungus, Penicillium verruculosum via protoplast fusion was investigated. The cellulolytic activities of the six fusants, finally selected for their hyper-cellulolytics were 2 times of those of wild type and 1.2 to 4.4 times of those parental auxotrophs. It was confirmed that the nuclear fusion occurred in fusants by their DNA contents and nuclear staining with Giemsa. It was also found that the fusants were aneuploids, and their genetic stability was demonstrated from the subculture for four months.