• Transactions of the Korean Society of Machine Tool Engineers
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• v.15 no.1
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• pp.102-107
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• 2006

This study investigates the properties as the difference friction welding area on SM25C steel rod. The tensile and bending strength and of welded joints, the hardness distribution of welds, the microstructure of welds and the tensile fracture surfaces were mainly investigated through this experiment. The fixed friction welding conditions were revolution 2000rpm, friction pressure 70Mpa, friction time 1.5sec, upset pressure 100Mpa, upset time 2.0sec, upset length 2.8mm and changeable friction welding parameter was friction welding area.

• Journal of the Korean Society for Precision Engineering
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• v.26 no.8
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• pp.104-111
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• 2009

In this paper, the gear design program is presented. The profile of gears is created using classical mathematic formulations. In each gear, a kinematic joint is applied and one can define the 20 contact condition between gear pairs. Initial and boundary conditions such as force, torque, velocity, acceleration, etc. can be set. Thus, it is possible to analyze dynamic characteristics of gear pairs such as reaction moment and the variation of angular velocity. In order to find the optimal profile of gear pairs, two optimization methods based on design of experiments are inserted in the program; One is the Taguchi method and the other is the response surface analysis method. To verify the program, the rack & pinion gear is created and analyzed. Simulation results show that the developed program is useful and result data is reliable.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2005.05a
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• pp.179-183
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• 2005

In apply roof waterproof system using of synthetic high polymer sheet for rooftop measure physical performance (tension$\cdot$tearing ability, temperature relativity, heating stretch performance, junction performance, wind resistance test) by various test environment condition waterproof test of structure and performance of construction work aspect, present suitable form of construction work under these environment. Also, wish to improve durability of concrete structure as that examine in priority about adhesion method and joint junction method with waterproof out surface, and present new direction about roof system application of waterproofing method for rooftop.

• Journal of Biomedical Engineering Research
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• v.30 no.5
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• pp.381-392
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• 2009

Due to the aging effect, older people have relatively weaker muscular performance, less range of motion in the joint articulation, and the lower sense of equilibrium than younger people. These factors attribute to their slow and clumsy ingress/egress motion. In order to analyze ingress/egress motion strategy of the elderly, healthy thirty 65 or more years old volunteers were recruited. The health condition of the each volunteer was verified by the medical checkup and also their physical capabilities were quantified by six fitness tests. Through the video analysis, older driver's ingress/egress motion strategies were classified and statistically investigated. For a comparison purpose, another thirty young volunteers also participated in the same test protocol and their ingress/egress motion strategies were also included in the statistical analysis.

• The Journal of the Korean bone and joint tumor society
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• v.1 no.2
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• pp.249-253
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• 1995

The fibrous dysplasia is a progressive and disabling condition that lead to deformity, especially weight bearing bones. The morbidity that is associated with the polyostotic fibrous dysplasia is the recurrent fracture and deformity. Various methods of treatment had been failed to control this problem. We used osteotomy and reconstruction nailing for polyostotic fibrous dysplasia occured in the proximal part of right femur with varus deformity and reconstruction nailing in left femur without osteotomy, and interlocking intramedullary nailing in right tibia to prevent pathologic fracture. These methods brought a good result of bone union and full weight bearing ambulation after 1 year and 6 month follow up. We think these methods are useful methods to control refracture and deformity, so we reported this case with bibliographic reviews.

• Proceedings of the Korea Concrete Institute Conference
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• 1994.10a
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• pp.291-300
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• 1994

The influence of elevated temperatures on the mechanical properties of concrete is important for fire-resistance studies and also for understanding the behavior of containment vessel, such as nuclear reactor pressure vessels, during service and ultimate condition. The present study is to clarify the damage/deterioration of concrete structures that are subjected to high temperature exposure. To this end, comprehensive experiments are conducted. The major test variables are the peak temperatures, rate of temperature increase, and sustained duration at peak temperature. The results include weight loss residual compressive strength and stress-strain curve. From those results, residua compressive strength formula and stress-strain relationship are proposed.

• Natural Product Sciences
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• v.20 no.1
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• pp.17-21
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• 2014

The combined new phytoformula (CAS), a mixture (5 : 3 : 2, w/w/w) of the ethanol extracts of the roots of C. officinalis and A. japonica, and the n-butanol fraction of the S. subprostrata strongly inhibited arthritic severity score as well as IL-6 production in serum of collagen-induced arthritic mice. Histological observation also indicated that the CAS-treated group showed less breakdown of joint cartilage of the collagen-treated mice. In contrast, C. officinalis alone or a combination of A. japonica and S. subprostrata did not show significant inhibitory action on the same animal model. Thus, it is thought that CAS possesses a synergistic inhibitory action on arthritic condition. All these results strongly suggest that CAS may be a potential anti-arthritic agent.

• Journal of the Korean Society of Safety
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• v.13 no.2
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• pp.13-21
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• 1998

This is a study on the natural vibration characteristics of Vehicle frame. Nowadays, many trucks freight the over-load, do the car designers consider the over-load about 200% in the design. It's necessary to make the model of a vehicle and simulate it for the test of driving condition, durability and vibration behavior before the vehicle is manufactured. If it is possible to make a simulation using the static and dynamic analysis, this is very useful in accomplishing an optimal design of the vehicle. In this paper, we studied the vibration characteristics of a truck body frame. The automobile body frame model for experiment is made smaller than real size frame with the ratio of 1/10. The vibration characteristics of a frame is considered as one of main factors in analyzing and improving the problem for ride comfort, noise and vibration reduction. Therefore, we experimented two method to neglect the nonlinearity. First is bolting and second is welding at the joint section. We compared computer simulation results and experimental data.

• The Korean Journal of Pain
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• v.29 no.4
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• pp.274-276
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• 2016

Chronic pelvic pain in women is a very annoying condition that is responsible for substantial suffering and medical expense. But dealing with this pain can be tough, because there are numerous possible causes for the pelvic pain such as urologic, gynecologic, gastrointestinal, neurologic, or musculoskeletal problems. Of these, musculoskeletal problem may be a primary cause of chronic pelvic pain in patients with a preceding trauma to the low back, pelvis, or lower extremities. Here, we report the case of a 54-year-old female patient with severe chronic pelvic pain after a transcutaneous electrical nerve stimulation (TENS) accident that was successfully managed with image-guided trigger point injections on several pelvic stabilizing muscles.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.05a
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• pp.48.1-48.1
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• 2011

In this presentation, We monitored weather data, such as global irradiance, ambient temperature, temperature of PV module, relative humidity and windspeed for 2 years, for determining accelerated test condition. then, we determined the temperature limit of accelerated test through weather data and FEM analysis. Detailed procedures will be summarized in this work. After analysing outdoor stress such as thermal stress, we decided main failure modes and mechanisms of PV module, especially solder joint of ribbon wire. we carried out the measurement of material properties such as thermal expansion coefficient for planning of accelerated test. we designed accelerated test based on FEM analysis results. we carried out thermal cycling test with 1 cell mini module for 3 months. We monitored the change of electrical performance every 1 week such as Voc, Isc, Pmax, etc. and then, we analized the ribbon wire/electrode intefaces. Detailed results will be summarized in this work.