• KSCE Journal of Civil and Environmental Engineering Research
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• v.12 no.4_1
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• pp.9-21
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• 1992

The effectiveness of the isolation system installed at the base of the primary structure and at the support of the substructure mounted on the primary structure is evaluated for reducing of structural responses under different earthquakes in this paper. The structural responses are analyzed to identify its behavior due to the input motion characteristics such as various peak acceleration and frequency content. Three analytical models are used to evaluate the effectiveness of the isolation system in this study as follows: fixed-base primary structure with support-fixed substructure, base-isolated primary structure with support-fixed substructure, and fixed-base primary structure with support-isolated substruciure. A computer code (KBISAP) is used for numerical integration of equation of motion considering the interaction between the primary structure and the secondary structure. The matrix condensation technique and constant average acceleration method are utilized in this program. And also, the effective stiffness of the base-isolator on reducing the structural response are evaluated for various earthquakes through the relationship of the acceleration - displacement.

• Journal of the Korea institute for structural maintenance and inspection
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• v.11 no.5
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• pp.197-211
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• 2007

The deteriorated PSC Beam bridge is necessary improved reinforcement method. In the study, it is proposed the box reinforcing method which could make the stiffness of the PSC Beam bridges increase more stably through the secondary composition effect of open type PSC Beam bridge's girder which is converted into the consolidation box type and the half panel is formed between the lower flange of the PSC Beam about the deteriorated PSC Beam bridge suffering the capacity decline. In case the proposed reinforcement method combine with the existed external prestressed method, the close analysis depending on the time is conducted by the construction stage because of searching the effect of reinforcement quantitatively. The reinforcement method of the box type which is proposed an efficiency improvement in objective in application case, by a reinforcement method after proposing the whole and bend sectional reinforcement method, against a each reinforcement method evaluated the upward camber which it follows in secondary composite effect and a member stress characteristics. Also, the structural safety of PSC Beam bridge is evaluated quantitatively by examining of rating factor through load carrying capacity evaluation.

• Journal of muscle and joint health
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• v.22 no.2
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• pp.138-147
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• 2015

Purpose: The study was conducted to identify factors influence suicidal ideation among older adults with osteoarthritis. Methods: This study used a cross-sectional design with secondary analysis of the Korean National Health and Nutrition Examination Survey. Data for 174 men and 939 women who aged${\geq}65$, and were diagnosed osteoarthritis from the Korea National Health and Nutrition Examination Survey 2010~2012 were included. Suicidal idea, age, sex, education, marital status, living alone, income, body mass index, smoking and alcohol use, exercise, perceived health status, activity limitation, joint pain and stiffness, depressive mood, and perceived stress were measured. Influencing factors and odds ratios were analyzed using complex sample multivariate logistic regression. Results: In the results, 29.9% of the elderly with osteoporosis had suicidal idea. The adjusted odds ratios (ORs) of suicidal ideation were significantly higher among those over 80 years older (OR=2.88, 95% CI=1.49~5.58), those with depression (OR=4.01, 95% CI=2.66~6.04), and those with high levels of stress (OR=2.76, 95% CI=1.79~4.24). Conclusion: Therefore, older adults with osteoarthritis should be screened for depression and stress to decrease suicidal ideation and prevent suicide attempt.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2014.04a
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• pp.408-414
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• 2014

After drilling operations at the offshore plant to production to crude oil to high pressure. After that time the low pressured of pipe inside when the secondary produce so oil recovery is reduced. At that time injection sea water at the pipe inside through water injection pump that the device Increase recovery so to be research and development at many industry. So developing 3-stage water injection pump at the domestic company. A variety of mathematical analysis during the detailed design analysis was not made through the dynamics characteristic. In this paper, a 2D finite element analysis is performed through the dynamics of the present study was the validation of the model.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2003.04a
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• pp.193-200
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• 2003

This paper presents a hybrid (i.e., integrated passive-active) system for seismic response control of a cable-stayed bridge. Because multiple control devices are operating, a hybrid control system could alleviate some of the restrictions and limitations that exist when each system is acting alone. Lead rubber bearings are used as passive control devices to reduce the earthquake-induced forces in the bridge and hydraulic actuators are used as active control devices to further reduce the bridge responses, especially deck displacements. In the proposed hybrid control system, a linear quadratic Gaussian control algorithm is adopted as a primary controller. In addition, a secondary bang-bang type (i.e., on-off type) controller according to the responses of lead rubber bearings is considered to increase the controller robustness. Numerical simulation results show that control performances of the hybrid control system are superior to those of the passive control system and slightly better than those of the fully active control system. Furthermore, it is verified that the hybrid control system with a bang-bang type controller is more robust for stiffness perturbation than the active controller with μ-synthesis method and there are no signs of instability in the overall system whereas the active control system with linear quadratic Gaussian algorithm shows instabilities in the perturbed system. Therefore, the proposed hybrid protective system could effectively be used to seismically excited cable-stayed bridges.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.29 no.3
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• pp.227-232
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• 2007

The radial forearm fasciocutaneous flap(RFFF) is a well-known flap for the reconstruction of oral and maxillofacial defects. It was first described by Yang et al. in 1981 and Soutar et al. developed it for the reconstruction of intraoral defect. RFFF provides a reliable, thin, and pliable soft tissue/skin paddle that is amenable to sensate reconstruction. It also has a long vascular pedicle that can be anastomosed to any vessel in either the ipsilateral or contralateral neck. However, split thickness skin graft(STSG) is most commonly used to cover the donor site, and a variety of donor site complications have been reported, including delayed healing, swelling of the hand, persistent wrist stiffness, reduced hand strength, and partial loss of the graft with exposure of the forearm flexor tendon. Various methods for donor site repair in addition to STSG have been developed and practiced to minimize both functional and esthetic morbidity, such as direct closure, V-Y closure, full thickness skin graft, tissue expansion, acellular dermal graft. We got a good result of using artificial dermis($Terudermis^{(R)}$) and secondary STSG for the repair of RFFF donor site defect esthetically and report with a review of literature.

• Archives of Plastic Surgery
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• v.35 no.1
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• pp.92-95
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• 2008

Purpose: Heterotopic ossification in pressure sore patients is reported to rarely develop, but once it occurs, it frequently causes joint stiffness and mobilization restriction. The aim of this article is to report our experience of atypical bone growing at femur neck fracture site with chronic, extensive pressure sore in patient with paraplegia secondary to spinal injury. Methods: A 28-year-old male patient presented with atypical bone growth at femur neck fracture site with pressure sore. He had undergone atypical growth bone removal and separation of united iliac bone and femur, and then pressure sore was covered by advanced rotation flap. Results: The patient mobilized hip joint and rode in a wheelchair. Complications such as dehiscence, infection, hematoma and flap necrosis did not occur. Conclusion: We experienced successful correction of atypical bone growth removal and recovery of pressure sore. We report our experience of atypical bone growth of fracture site and the related literature was reviewed.

• Transactions of the Korean Society of Automotive Engineers
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• v.20 no.2
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• pp.47-55
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• 2012

This work deals with dynamic analysis of a monorail system with magnetic caterpillar where magnets are embedded inside each articulated element of the caterpillar, augmenting traction force of main rubber wheels to climb up slope up to 15 degree grade. Considerations are first given to determine stiffness of the primary and secondary suspension springs in order for the natural frequencies of car body and bogie associated with vertical, pitch, roll and yaw motion to be within generally accepted range of 1-2 Hz. Equations for calculating magnetic force needed to climb up given slope are derived, and a magnetic caterpillar system for 1/6 scale monorail is designed based on the derivation. To assess the hill climbing ability and cornering stability, and make sure smooth operation of the side and vertical guiding wheels which is critical for safety, a multibody model that takes into account of every component level design characteristics of car, bogie, and caterpillar is set up. Through hill climbing simulation and comparison with measurement of the limit slope, the validity of the analysis and design of the magnetic caterpillar system are demonstrated. Also by studying the curving behavior, maximum curving speed without rollover, functioning of lateral motion constraint system, the effects of geometry of guiding rails are studied.

• Steel and Composite Structures
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• v.47 no.3
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• pp.315-337
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• 2023

The steel structure is an assembly of individual structural members joined together by connections. The connections are the focal point to transfer the forces which is susceptible to damage easily. It is challenging to replace the affected connection parts after an earthquake. Hence, steel plates are utilised as a structural fuse that absorbs connection forces and fails first. The objective of the present research is to develop a beam-column end plate connection with single and dual fuse and study the effect of single fuse, dual fuse and combined action of fuse and damper. In this research, seismic resilient beam-column end plate connection is developed in the form of structural fuse. The novel connection consists of one main fuse was placed horizontally and secondary fuse was placed vertically over main fuse. The specimens are fabricated with the variation in number of fuse (single and dual) and position of fuse (beam flange top and bottom). From the fabricated ten specimens five specimens were loaded monotonically and five cyclically. The experimental results are compared with Finite Element Analysis results of Arunkumar and Umamaheswari (2022). The results are critically assessed in the aspect of moment-rotation behaviour, strain in connection components, connection stiffness, energy dissipation characteristics and ductility. While comparing the performance of total five specimens, the connection with fuse exhibited superior performance than the conventional connection. An equation is proposed for the moment of resistance of end-plate connection without and with structural fuse.

• Journal of the Korean Arthroscopy Society
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• v.12 no.1
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• pp.53-57
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• 2008

Purpose: We analyzed the clinical results after arthroscopic treatment in acute pyogenic arthritis of the knee. Materials and Methods: From July 2000 to January 2005, we reviewed 16 cases(15 patients) of acute pyogenic arthritis of the knee on which arthroscopic treatment was done. The mean age was 61.9 years and the mean follow-up period was 30.5 months. There were 8 cases with diabetes or degenerative osteoarthritis and 14 cases with acupuncture or intraarticular injection history. Results: Causative organisms were identified in 7 cases. The average postoperative antibiotics were used intravenously for 25.5 days and per orally for 22.5 days. There were 11 complications; 5 cases of partial ankylosis, 2 cases of secondary arthritis, 1 case of chronic osteomyelitis and 3 cases of death. Patients with over 3 week immobilization had higher rate of stiffness of knee joint(p=0.032) but there was no significant difference between the symptom to treatment duration and the incidence rate of complications(p=0.293). The cases of which the causative organism was detected had higher incidences of complications(p=0.034). Conclusion: The incidence of joint stiffness was higher in the patients of longer immobilization. More complications were detected in the cases of which the causative organism is detected.