• Journal of the Earthquake Engineering Society of Korea
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• v.18 no.3
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• pp.133-140
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• 2014

The friction damper can be used for improving the seismic resistance of existing buildings. The damper is often installed in bracing members. The energy dissipation capacity of the damping systems depends on the type of the structure, the configuration of the bracing members, and the property of dampers. In Korea, there are numerous low- to mid-rise reinforced concrete moment frames that were constructed considering only gravity loads. Those frames may be vulnerable for future earthquakes. To resolve the problem, this study developed a toggle bracing system with a high density friction damper. To investigate the improvement of reinforced concrete frames after retrofit using the developed damped system, experimental tests were conducted on frame specimens with and without the damped system. The results showed that the maximum strength, initial stiffness and energy dissipation capacity of the framed with the damped system were much larger than those of the frame without the damped system.

• Korean Journal of Adult Nursing
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• v.23 no.1
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• pp.10-19
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• 2011

Purpose: The purpose of this study was to evaluate the impact of a protocol of cryotherapy and Tai Chi on women with Fibrolmyalgia Syndrome. Methods: The study design was a pretest and posttest quasi-experimental, nonrandom assignment. The subjects were 48 outpatients with a diagnosis of fibromyalgia based on the American College of Rheumatology Standards. The setting was a University Medical Center in S city. The protocol was self administered ten times a week, for a two week period resulting in twenty treatments. Results: A protocol of cryotherapy and Tai Chi self-help program showed significant improvement in the fibromyalgia impact as measured by reports of physical impairment, feeing good, number of missed work days, ability to perform work, reports of pain, fatigue, rest, stiffness, anxiety and depression as reported by the comparison group (p<.001). No significant differences between the two regarding in reports of the tender points (p=.062). Conclusion: The results suggested that a protocol of cryotherapy and Tai Chi self-help program may be a promising multidisciplinary strategy for fibromyalgia patients.

• Geomechanics and Engineering
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• v.12 no.5
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• pp.863-870
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• 2017

With the increasing interest in using bacterial biofilms in geo-engineering practices, such as soil improvement, sealing leakage in earth structures, and hydraulic barrier installation, understanding of the contribution of bacterial biofilm formation to mechanical and hydraulic behavior of soils is important. While mechanical properties of soft gel-like biofilms need to be identified for appropriate modeling and prediction of behaviors of biofilm-associated soils, elastic properties of biofilms remain poorly understood. Therefore, this study investigated the microscale Young's modulus of biofilms produced by Shewanella oneidensis MR-1 in a liquid phase. The indentation test was performed on a biofilm sample using the atomic force microscopy (AFM) with a spherical indentor, and the force-indentation responses were obtained during approach and retraction traces. Young's modulus of biofilms was estimated to be ~33-38 kPa from these force-indentation curves and Hertzian contact theory. It appears that the AFM indentation result captures the microscale local characteristics of biofilms and its stiffness is relatively large compared to the other methods, including rheometer and hydrodynamic shear tests, which reflect the average macro-scale behaviors. While modeling of mechanical behaviors of biofilm-associated soils requires the properties of each component, the obtained results provide information on the mechanical properties of biofilms that can be considered as cementing, gluing, or filling materials in soils.

• The Journal of Internal Korean Medicine
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• v.21 no.3
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• pp.515-519
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• 2000

Developing of antibiotic, bacterial meningitis is one of the disease of high mortality. Especially in case of gram negative, pneumococal meningitis, they have high mortality and neurological disorders after treatment. Main symptoms of bacterial meningitis are fever, headache, vomit, neck stiffness and coma etc. In oriental medicine, acute feverish infectious diseases have been treated as wenbing(溫病). We can divide wenbing into 8 kinds. Bacterial meningitis is included as Chunwen(春溫), fengwen(風溫) in the sight of similarity on the symptoms and falling ill. Comparing with CVA, we have too rare cases of treating bacterial meningitis with oriental medicine. A case of sequelae of bacterial meningitis patient diagnosed as Chunon, pungon showed prominent improvement by herb med and acupuncture treatment etc.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.45 no.5
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• pp.44-48
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• 2013

Ultrasonic treatment of KOCC was tried to explore the possibility for improvement of KOCC quality as a raw material for making industrial packaging paper and paperboard. The effect of pH, stock consistencies and treatment times on the ultrasonic response of KOCC were investigated. WRV, apparent density, tensile index and burst index were improved as pH of KOCC slurry is increased. However highest tear index and stiffness were obtained at pH 8. It was also found that the highest WRV and strength properties could be obtained at 0.5% of KOCC consistency during ultrasonic treatment. WRV and most strength properties were improved with ultrasonic treatment time. It was found that ultrasonic treatment can be used as a useful mean for KOCC modificaton.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.11a
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• pp.680-685
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• 2006

The latest trend in the automotive industry demands the development of high stiffness car bodies and the securement of inter-system performance for low vibration and noise vehicles. This demand, however, conflicts with need for light weight design and greater fuel efficiency, thus raising the importance of optimization design to satisfy both developmental goals. We chose two European medium sedans, which has gasoline engine and diesel one, to elucidate the noise characteristics of diesel passenger cars, whose sales have been increasing in both Korea and Europe. In the present study a systematic experiment was conducted to analyze the noise characteristics in diesel cars. we made it possible for differentiating car management according to customer demand while allowing for improved commercial feasibility. it was possible to improve interior noise by 2 dB(A) on average sound pressure level. As a result, by 4% higher on articulation index(AI).

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.11a
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• pp.464-473
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• 2006

This paper summarises theoretical and experimental work on the feedback control of sound radiation from honeycomb panels using piezoceramic actuators. It is motivated by the problem of sound transmission in aircraft, specifically the active control of trim panels. Trim panels are generally honeycomb structures designed to meet the design requirement of low weight and high stiffness. They are resiliently-mounted to the fuselage for the passive reduction of noise transmission. Local coupling of the closely-spaced sensor and actuator was observed experimentally and modelled using a single degree of freedom system. The effect of the local coupling was to roll-off the response between the actuator and sensor at high frequencies, so that a feedback control system can have high gain margins. Unfortunately, only relatively poor global performance is then achieved because of localisation of reduction around the actuator. This localisation prompts the investigation of a multichannel active control system. Globalised reduction was predicted using a model of 12 channel direct velocity feedback control. The multichannel system, however, does not appear to yield a significant improvement in the performance because of decreased gain margin.

• Journal of Korean Public Health Nursing
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• v.28 no.1
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• pp.32-45
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• 2014

Purpose: The purpose of this study was to test the effectiveness of an eight session integrated case management program for improvement of medication adherence, physical function, pain, and depression among medical aid beneficiaries with osteoarthritis. Method: A nonequivalent control group pre-posttest design was employed. Participants were 55 medical aid beneficiaries who agreed to participate in this study, and were assigned to an experimental group (n=28) or control group (n=27). The framework of this research derived from Cox's Interaction Model of Client Health Behavior guided the overall intervention and the components. The program led by a case manager with a medication calendar, motivating interviewing and coaching strategies and collaboration with a pharmacist. Analysis included change in scores, ${\chi}^2$-test, and t-test. Result: The results showed significant increase in medication adherence, physical function and decrease joint pain, joint stiffness and depression in the experimental group compared to the control group. Conclusion: The eight session integrated case management program indicated an effect on medication adherence, pain, physical function, and depression. Partnership with a pharmacist is recommended for medication adherence and conduct of further studies will be needed in order to determine the long-term effect of an extended integrated program on health outcomes.

• Journal of the Korea Concrete Institute
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• v.11 no.5
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• pp.3-10
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• 1999

Earthquake resistant R/C frame structures are generally designed to prevent the columns from plastic hinging. R/C columns under higher axial load or strong earthquake showed a brittle behavior due to the deterioration of strength and stiffness degradation. An experimental study was conducted to examine the behavior and to find the relationship between amounts of lateral reinforcements and compressive strength of ten R/C column specimens subjected to reversed cyclic lateral load and higher axial load. Test results are follows : An increase in the amount of lateral reinforcement results in a significant improvement in both ductility and energy dissipation capacities of columns. R/C columns with sub-tie provide the improved ductility capacity than those with closely spaced lateral reinforcement only. While the load resisting capacity of the high strength R/C columns is higher than the normal strength concrete columns under both an identical ratio of lateral reinforcement, however the ductility capacity of high strength R/C columns is decreased considerably. Therefore, the amounts of lateral reinforcement must be designed carefully to secure the sufficient ductility and economic design of HSC columns under higher axial load.

• Journal of the Korean Society for Precision Engineering
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• v.33 no.10
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• pp.851-856
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• 2016

Planetary gear systems have several advantages over traditional gearboxes with parallel axis gear shafts. The planetary gearbox arrangement also creates greater stability due to the even distribution of mass and increased rotational stiffness. However, gears in planetary gear systems occasionally have a short-life due to wear and breakage by repetitive load during operation time. In this study, we evaluated variables of the strength design for each part and conducted structural analysis of seven cases of the planetary gear system. The result of structural analysis was applied to shape optimization method and obtaining the weight lightening designed value. Subsequently, the planetary gear system was performed to ensure the durability of gears during operation time with miner's rule.