• Structural Engineering and Mechanics
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• v.73 no.3
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• pp.303-317
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• 2020

In this study an innovative rocking zipper braced frame (RZBF) is proposed to overcome the deficiencies of common concentrically braced frames. RZBF is an improved rocking concentrically braced frame which is based on combination of rocking behavior and zipper columns. The base rocking joints and post-tensioned bars provide rocking response and restoring force, respectively. Also, zipper columns distribute the unbalance force over the frame height and reduce the damage concentration. To evaluate seismic performance of RZBF, a comparison study is carried out considering concentrically braced frame, zipper braced frame, rocking concentrically braced frame and RZBF. Thereby, a suite of non-linear time history analyses had been performed on four different types of archetypes with four, six, eight, ten and twelve stories. Frames were designed and non-linear time history analyses were conducted in OpenSees. To compare the seismic behavior of the archetypes, roof drifts, residual roof drifts, story drifts, the forces of first and top story braces, PT bars forces, column uplift and base shears were taken in to consideration. Results illustrate that using RZBF, can reduce the damage due to reduced residual drifts. Zipper columns enhance the seismic performance of rocking systems. As the number of stories increase in the RZBF systems, larger top story braces were needed. So the RZBF system is applicable on low and midrise buildings.

• International Journal of Advanced Culture Technology
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• v.9 no.3
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• pp.152-159
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• 2021

Small local businesses such as corner shops and street markets have been severely impacted by the COVID-19 pandemic and declining consumption. A community currency is a local currency that can be used to exchange for one of the local currencies within an online community. Community currencies can be effective not only in supporting small businesses, but also in helping the local economy more vibrant, benefiting consumers in the community. An important goal of Community Currency is to foster a vibrant local economy by building mutually beneficial relationships between local business owners and customers. The purpose of this study was to identify how the existing community currencies of participating SMEs and self-employed in Seoul and Gyeonggi-do metropolitan areas contributed to commercial revitalization by category and to suggest a new or better approach to community currency operation. It also focused on presenting the best solutions for the future direction of mobile community currencies, measures that are better than current currency operations, revitalize the community and develop the economy.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.11
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• pp.191-204
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• 2018

In the era of diversity and creativity, autonomous regional regeneration is being emphasized. Local regeneration effects through local heritage utilization and the value of regional properties are rising. It is very meaningful to find a way to revitalize the urban regeneration system that can transform the facilities, spaces and industries in underdeveloped regions into opportune properties. This study explores the possibility of self-sustaining development by establishing an endogenous self-reliance system through the localization of industrial heritage. Competitive advantage strategies of regional properties are more important than regional comparative advantages. In the future, more attention should be paid to the intangible value of the city. A genuine city revival should be created as a place with cultural identity through artistic ecology, tradition, community, and aesthetics centering on people.

• Steel and Composite Structures
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• v.21 no.4
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• pp.863-882
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• 2016

This study aims to introduce a new bracing system by which even super-wide frames with large openings can be braced. The proposed system, hereafter called Cable-Pulley Brace (CPB), is a tension-only bracing system with a rectilinear configuration. In CPB, a wire rope passes through a rectilinear path around the opening(s) and connects the lower corner of the frame to its opposite upper one. CPB is a secondary load resisting system with a nonlinear-elastic hysteretic behavior due to its initial pre-tension load. As a result, the required energy dissipation would be provided by the MRF itself, and the main intention of using CPB is to contribute to the initial and post-yield stiffness of the whole system. Using a stiffness calibration technique, optimum placement of the CPBs is discussed to yield a uniform displacement demand along the height of the structure. A displacement-based design procedure is proposed by which the MRF with CPB can be designed to achieve a uniform distribution of inter-story drifts with predefined values. Obtained results indicated that CPB leads to significant reductions in maximum and residual deformations of the MRF at the expense of minor increase in the maximum base shear and developed axial force demands in the columns. In the case of a typical 5-story residential building, compared to SMRF system, CPB system reduces maximum amounts of inter-story and residual drifts by 35% and 70%, respectively. Moreover, openings of the frame are not interrupted by the CPB. This is the most appealing feature of the proposed bracing system from architectural point of view.

• The Korean Journal of Health Service Management
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• v.5 no.3
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• pp.101-110
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• 2011

This study analyzed affecting factors of employees working at dental hospitals to the organizational commitment and service quality, and then tried to utilize it as a basic data in executing personnel training policies for dental hospital's practitioners. The survey was conducted from July 1st to July 30th, 2010, and used 193 copies for this research analysis. As a hypothetical verification result through regression analysis, means and capabilities among empowerment factors influenced significant positive (+) effects, and self-determination and influences did not make significant effects. Also, organization commitment was displayed as influencing significant positive (+) effects to the service quality. When considering this research's results as a basement, an alternative for the managerial innovation shall be established for promoting mutual developments of individuals and organization in midst of promptly changing economic environments. That is, a personal training system has to be set up in which more decision-making rights on given assignments of dental hospital's employments are endowed, and then responsibilities are directed to be charged so much by introducing the empowerment concept instead of the managerial technique centering on controls.

• Journal of KIBIM
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• v.5 no.1
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• pp.44-53
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• 2015

Recently, BIM has been widely applying in civil engineering projects centering on the private construction industry in order to establish self guidelines for spreading in practice. However, most BIM technologies and software are based on the architectural projects. In these environments, it is not easy to apply the BIM to a infrastructure field. Even BIM standards with IFC (Industry Foundation Classes) are also focusing on architectural projects. Especially, both private and public sectors do not know about how BIM delivery system should be performed, and how such deliverable should be submitted to the government yet. Thus, we need to analyze an application level of BIM S/W (Software) in real projects and verify their interoperability. Besides, since there are not any common standards that can exchange IFC models for civil engineering projects, we have many issues in converting as-built infrastructure models into IFC and delivering their design documents to the government. Accordingly, this study aims to perform a BIM process with commercial software for real road project after a detailed design process is finished and verify interoperability between diverse BIM software for securing BIM data reliability.

• Journal of the Korean Institute of Navigation
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• v.10 no.1
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• pp.81-100
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• 1986

Self-contained portable remote-indicating magnetic compass was designed and tested. Its sensing part consists of main scale disk of rotary encoder with photo-etched 180, oopaque slits and three pairs of light sources and detectors seperated by a transparent index scale, so that any angular deflection of main scale disk against the bowl may be detected optically. The outputs from the sensing part are transformed into digital ship's course indication by electronics unit which consists of operational amplifier, phase discriminator, up-down counter and counting starter circuit. The results from testign the above compass with turntable at variable rate of turn are as following : 1) The main scale disk deflection against the bowl can be detected without any disturbing influence to the freedom of its north-seeking function. 2) The digital indication resolution is found to be $\circ \pm$1 degree. 3) Misrepresenting indication can be avoided by ensuring dimension uniformity and arrangement accuracy of slits on main and index scale disks and by centering pivot in the encoder disk. 4) Indication resolution should be improved by modifying the signal processing and by doubling the number of slits on compass card. 5) Further study should be made on developing non-conductive compass liquid, analogue repeater driving system and more compact processing element.

• Structural Engineering and Mechanics
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• v.73 no.4
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• pp.447-454
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• 2020

Seismic isolation technology has a wide application to protect bridges from earthquake damage, a new designed bridge pier with seismic isolation are provided for railways in seismic regions of China. The pier with rocking isolation is a self-centering system under small and moderate earthquakes, and the unbonded prestressed tendons are used to prevent overturning under strong earthquakes. A numerical model based on pseudo-static testing results is presented to evaluate the seismic performance of isolation bridge piers, and is validated by the shaking table test. It is found that the rocking response and the loss of prestressing for the bridge pier increase with the increase of earthquake intensity. Besides, the intensity and spectral characteristics of input ground motion have great influence on displacement of the top and bottom of the bridge pier, while have less influence on the bending moment of the pier bottom. Experimental and numerical results show that the rocking-isolated piers presented in this study have good seismic performance, and it provides an alternative way for the railway bridge in the regions with high occurrence of earthquakes. Therefore, we provide the detailed procedures for seismic design of the rocking-isolated bridge pier, and a case study of the seismic isolation design with rocking piers is carried out to popularize the seismic isolation methods.

• Earthquakes and Structures
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• v.16 no.2
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• pp.209-219
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• 2019

Unbonded Post-Tensioned (UPT) precast concrete systems have been shown to provide excellent seismic resistance. In order to improve understanding of the dynamic response of UPT systems, a series of snap back tests on four UPT systems was undertaken consisting of one Single Rocking Wall (SRW) and three Precast Wall with End Columns (PreWEC) systems. The snap back tests provided both a static pushover and a nonlinear free vibration response of a system. As expected the SRW exhibited an approximate bi-linear inertia force-drift response during the free vibration decay and the PreWEC walls showed an inertia force-drift response with increased strength and energy dissipation due to the addition of steel O-connectors. All walls exhibited negligible residual drifts regardless of the number of O-connectors or the post-tensioning force. When PreWEC systems of the same strength were compared the inclusion of further energy dissipating O-connectors was found to decrease the measured peak wall acceleration. Both the local and global wall parameters measured at pseudo-static and dynamic loading rates showed similar behaviour, which demonstrates that the dynamic behaviour of UPT walls is well represented by pseudo-static tests. The SRW was found to have Equivalent Viscous Damping (EVD) between 0.9-3.8% and the three PreWEC walls were found to have maximum EVD of between 14.7-25.8%.

• The Journal of Korean Medicine
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• v.18 no.1
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• pp.101-125
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• 1997

Man pursues health as his basic right. Therefore, the government should try to preserve the right of the people's health and carry out the policy of medical treatment for that. But the system of our medical care is advantageous to the medical institutions, which produce medical goods each people buys and sells freely, more than to the maintenance and improvement of their health. That is to say, the first aim of the institution is not the healthy preservation of the people but their accumulation of riches. The medical conflicts are the social situation which is happening between those who produce medical treatment and the patients who consume it. Its behinning comes from the lack of belief by the inhuman relationship between patients and doctors. According to thelatest investigation, the patients of oriental clinics look more content than those who go to common hospitals. The reasons are as follows; fitness to one's physical constitution, the kind altitude of doctors and the view of oriental medicine toward human body. Though the content degreee is higher than western medicine, such conclusions result from the present condition the number of the patients is less. In short, the first, since the right of patients is higher and the fields make more variors and popular, the conflicts and mistakes go on increasing. The second, in their activity of treatment, the legal importance of atlention and explanatory obligation should be considered seriously so as not to break out medical mistakes. The third, in the center of technical books which are accepted by the academic world, the clinical exertion doing treatment is needful. The fourth, as the direct order of medical justification the self-determination of patients should be respected. The fifth, because the process and record of treatment become important in the time of emergency legally, the conversations and movements as well as the details of treatment must be recorded. The sixth, the academic effort about the settlement institution or the legal system is necessary.