• Proceedings of the Computational Structural Engineering Institute Conference
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• 1995.10a
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• pp.1-8
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• 1995

This work presents a new method to deal with buckling constraints. The mathematical optimization process of truss structures proposed earlier by the author has been proved to be the most rigorous method. The inclusion of buckling constraints, however, gives rise to a new problem The allowable compression stress of a member changes from one design iteration to another. This changing stress limit creates a good deal of noise in selecting active constraints and makes the solution process unstable. This problem can be overcome by introducing relaxation parameters. This work, however, aims at establishing a more rigorous method by containing the allowable compression stress in the left hand side of the associated constraint.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.25 no.5
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• pp.433-438
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• 2012

This paper is the second paper among two papers which constitute the paper about the structural design of a dental implant. This paper completed the test drafting for the structural model of the new dental implant whose structural performance was confirmed and verified through the comparative structural analysis carried out in the first paper. This paper finished the structural design of a dental implant by manufacturing the dental implant using CNC machines and so forth on the basis of the completed draft and finally by evaluating the machining condition of the dental implant. The drafting work was performed using MDT(Mechanical Desk Top). The manufacturing work was carried out using CNC machines, general purpose milling machine, and Wire EDM. The manufactured surface condition of the dental implant was evaluated and confirmed finally using an electron microscope. As a result of evaluation, a testing dental implant with very good condition was designed and manufactured.

• Journal of the Korea institute for structural maintenance and inspection
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• v.4 no.4
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• pp.129-140
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• 2000

Retaining wall is a constructed structure in order to construct road, rail, building for effective use and obtainments of the limited ground. Recently, many kinds of research have been actively developed for a standardization and information to the maintenance and management of bridge, tunnel, road. With the works of database construction of that, many kinds of data with respect to statistics is cumulated. Database work of retaining wall is wholly lacking and lagged behind in the works of database construction. This paper suggests classification system on inspection data. On the basis of that, code work with classification system was practised and DB program of inspection data of retaining wall was developed. And input work for a data of maintenance and management was practised. The purpose of this paper is to suggest a kind of statistics data and investigate a characteristics of inspection using statistic data on retaining wall.

• Journal of the Korean Society of Safety
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• v.24 no.6
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• pp.124-131
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• 2009

In any form of construction work, it is essential that accidents be prevented at every stage, from foundation preparation to build completion. For this, it is necessary to use models that can assess risk and provide instructions for safe work processes so that the risk of accidents is reduced. Currently, however, very few models can perform these tasks. In this paper, we present a model that assesses risk quantitatively by analyzing the risk factors involved in each stage of construction, such as foundation work, temporary work, structural work, equipment work, and finishing work. The model performs assessment based on examples of accidents and by investigating actual conditions during construction. In addition, we present in this paper a safety management system developed to assess risk during construction and to effectively train laborers.

• International Journal of Aerospace System Engineering
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• v.2 no.1
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• pp.38-42
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• 2015

This work is to propose a structural design and analysis procedure for development of the low noise 1kW class small wind turbine system which will be applicable to relatively low speed region like Korea and for the domestic use. The proposed structural configuration has a sandwich composite structure with the E-glass/Epoxy face sheets and the Urethane foam core for lightness, structural stability, low manufacturing cost and easy manufacturing process. Structural analysis including load cases, stress, deformation, buckling, vibration and fatigue life was performed using the Finite Element Method, the load spectrum analysis and Miner rule. In order to evaluate the designed structure, the structural test was carried out and its test results were compared with the estimated results. Moreover Investigation on structural safety of tower was verified through structural analysis by FEM.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2004.11a
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• pp.552-555
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• 2004

As the scale of building construction is larger and more complex, accident is increasing on the steel structure work process. But Safety-Inspection has been carried out through many other checklists in the workplace, it hasn't been used actively. Because checklist wasn't written at the level of specific work and applied scope is Insufficient. So, we must grasp accidental cause about detailed work for making safety management checklist accurately. For this study, we are confining a range to steel structure work of all the building construction. We will classify steel structure process into the detailed work for preventing accident. And we will grasp accidental cause about detailed work for developing the checklist in the future.

• The Journal of the Korea institute of electronic communication sciences
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• v.19 no.2
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• pp.427-436
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• 2024

Recently, the importance of information security (IS) has been socially recognized, leading organizations to adopt IS policies, secure specialized personnel, and demand IS compliance from employees. However, the implementation of these policies can disrupt existing work processes, causing resistance among employees. This study aims to elucidate the mechanism linking work stress, caused by IS policies that do not consider the work system, to individual job burnout and IS policy resistance. We established a research model and hypotheses based on previous studies and utilized structural equation modeling with data collected from organization members of companies that have implemented IS policies. The results of the structural equation modeling confirmed that work ambiguity and work impediment are linked to IS policy resistance through job burnout, characterized by emotional exhaustion and disengagement. Our findings suggest that the swift implementation of IS policies can provoke a backlash from employees, with stress being the primary cause. This paradoxically indicates the need for the development of organization-specific IS policies.

• Journal of Cardiovascular Imaging
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• v.31 no.4
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• pp.191-199
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• 2023

BACKGROUND: Assessment of left ventricular (LV) function plays a pivotal role in the management of patients with valvular heart disease, including those caused by rheumatic heart disease. Noninvasive LV pressure-strain loop analysis is emerging as a new echocardiographic method to evaluate global LV systolic function, integrating longitudinal strain by speckle-tracking analysis and noninvasively measured blood pressure to estimate myocardial work. The aim of this study was to characterize global LV myocardial work efficiency in patients with severe rheumatic mitral stenosis (MS) with preserved ejection fraction (EF). METHODS: We retrospectively included adult patients with severe rheumatic MS with preserved EF (> 50%) and sinus rhythm. Healthy individuals without structural heart disease were included as a control group. Global LV myocardial work efficiency was estimated with a proprietary algorithm from speckle-tracking strain analyses, as well as noninvasive blood pressure measurements. RESULTS: A total of 45 individuals with isolated severe rheumatic MS with sinus rhythm and 45 healthy individuals were included. In healthy individuals without structural heart disease, the mean global LV myocardial work efficiency was 96% (standard deviation [SD], 2), Compared with healthy individuals, median global LV myocardial work efficiency was significantly worse in MS patients (89%; SD, 4; p < 0.001) although the LVEF was similar. CONCLUSIONS: Individuals with isolated severe rheumatic MS and preserved EF, had global LV myocardial work efficiencies lower than normal controls.

• Magazine of the Korea Institute for Structural Maintenance and Inspection
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• v.18 no.4
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• pp.31-36
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• 2014

• Magazine of the Korea Institute for Structural Maintenance and Inspection
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• v.17 no.2
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• pp.77-87
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• 2013