• Clinics in Shoulder and Elbow
• /
• v.2 no.1
• /
• pp.8-13
• /
• 1999

The results of the operative treatment of the Grade III acromioclavicular joint injury is defined by the durability of the reduced joint and free of exertional pain. Several surgical techniques have been applied to reduce and stabilize the joints effectively. Resection of clavicular lateral end and subacromial decompression also could be applied to prevent post-operative arthritic change. Biomechanical studies reveals the role of clavicular elevation and rotation to achieve more than 90 degrees of elevation. It also serves as a attachment site of deltoid and trapezius muscle. The stability and mobility of the both acromioclavicular and coracoclavicular joint are important to get full functional recovery. We modified the methods of coracoacromial ligament transfer described by Weaver-Dunn and by Shoji et a!. to pre­vent pullout of the transferred ligament and to get more improved functional results. Main technical point was harvesting full thickness bone block and fix it through the key-hole to reduce pull out angle.

• Korean Journal of Applied Biomechanics
• /
• v.13 no.3
• /
• pp.15-26
• /
• 2003

This study was conducted to investigate the performance times, CM position and CM speed, pole chord length and pole chord angle, whole body angular momentum(X axis), and grip width in pole vault event according to the event and phase; touch down, pole plant, take-off, maximum pole bending pole straight, pole release, peak height, and foot contact, pole contact, free flight. The pole vaulting of four male elite vaulters including six trial were filmed using two video digital cameras at 60 Hz at 56th national athletic match, and data were collected through the DLT method of three dimensional cinematography. In general the better jumper is, the longer the performance time is. And the greater CM speed is, and the better his transformation ability of CM horizontal speed into vertical speed is. As he uses a longer pole, his grip is higher, and it is a enough for him to rock back his body, so that he pulls and pushes the pole well keeping his hips close to. An greater maximum angular momentum and early positioning of the hips parallel to the bar makes his body far side of the bar and his bar clearance easier. Specially our national jumper needs to have more powerful braking force during foot contact phase, and take his body on the pole after maximum pole bending, and pull and push the pole strongly keeping his hips close to. Also he needs to have stronger muscular strength in order to control the longer pole and use the pole of proper tension more efficiently.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2001.11a
• /
• pp.117-122
• /
• 2001

Recently, epoxy-coated re-bar used to the structure partly and put to practical use step, but not economical and appeared to the defect of deterioration of long term bond strength between concrete. The method for complement the defect of epoxy coated re-bar, study of polymer cement slurry coated re-bar started and basic properties appeared to excellent, but study of bond properties embedded in concrete specimens insufficient until now. This study attempts to examination of using possibility for bond strength of polymer cement slurry coated re-bar between concrete specimens compare to ACI Code and KS Code through pull-out test of 15cm$\times$15cm$\times$15cm specimens with polymer cement slurry coated re-bar as polymer cement ratio 50%, 100%, 150%, coating thickness 250${\mu}{\textrm}{m}$, 440${\mu}{\textrm}{m}$ and curing age. In the results of this study, the bond strength of polymer cement slurry coated re-bar compare to plain re-bar, epoxy coated re-bar decreased St/BA-modified polymer cement slurry coated re-bar, but bond strength of PA-modified polymer cement slurry coated re-bar appeared to excellent results. The bond properties of polymer cement slurry coated re-bar between concrete will be obtain more precise results according to compressive strength change of concrete and re-bar diameter size.

• International Journal of Highway Engineering
• /
• v.20 no.3
• /
• pp.19-26
• /
• 2018

PURPOSES : The main purpose of this study is suggest of field bond strength evaluation method for more objective evaluation method through Evaluation of Bond Strength Properties with changing aspect ratio and temperature. METHODS : The evaluation is laboratory bond strength test. Using the core machine, the pull-off test method ; the bond strength test of interface layer the universal testing machine. RESULTS : As a result of the laboratory bond strength evaluation, it was verified that the bond strength by aspect ratio decreases linearly with increasing aspect ratio and the bond strength properties by temperature change existed at high and low temperature condition relative to odinary temperature condition. CONCLUSIONS : According to the results of laboratory bond strength evaluation, the field bond strength evaluation results suggest applying the proposed correction factor (0.8, 1.0, 1.4, 1.9) according to aspect ratio(0.5, 0.1, 1.5, 2.0), For more objective evaluation of the bond strength, it is analyzed that the evaluation value is within $6{\sim}32^{\circ}C$ and the result can be obtained within 5% of the coefficient of variation.

• Computers and Concrete
• /
• v.26 no.2
• /
• pp.115-125
• /
• 2020

To reduce the damage of concrete in fire, a new type of lightweight cinder aggregate concrete was developed due to the excellent fire resistance of cinder. To further enhance its fire resistance, Polypropylene (PP) Fibers which can enhance the fire resistance of concrete were also used in this type of concrete. However, the bond behavior of this new type of concrete after fire exposure is still unknown. To investigate its bond behavior, 185 specimens were heated up to 22, 200, 400, 600 or 800℃ for 2 h duration respectively, which is followed by subsequent compressive and tensile tests at room temperature. The concrete-rebar bond strength of C30 PP fiber-reinforced cinder concrete was subsequently investigated through pull-out tests after fire exposure. The microstructures of the PP fiber-reinforced cinder concrete and the status of the PP fibre at different temperature were inspected using an advanced scanning electron microscopy, aiming to understand the mechanism of the bonding deterioration under high temperature. The effects of rebar diameter and bond length on the bond strength of PP fiber-reinforced cinder concrete were investigated based on the test results. The bond-slip relation of PP fiber-reinforced cinder concrete after exposure at different temperature was derived based on the test results.

• Proceedings of the Korea Contents Association Conference
• /
• 2007.11a
• /
• pp.777-780
• /
• 2007

In these days, tourism contents development has been continuously increases due to the appearance of online contents generation, development of cultural contents industry and the spreads of leisure life among the ordinary people's life and it needs more significant research and development for the tourism product's varieties. Story telling means that the explanation or interpretation of tour guide or guide book of the tourist spots, they role as important pull factor which can determine the image of tourism destination. And it make tourist discover the identification its own specific contents. The purpose of this study is on to examine methods tourism contents development through storytelling.

• Wind and Structures
• /
• v.18 no.6
• /
• pp.669-691
• /
• 2014

Since low-rise residential buildings are the most common and vulnerable structures in coastal areas, a reliable prediction of their performance under hurricanes is necessary. The present study focuses on developing a refined finite element model that is able to more rigorously represent the load distributions or redistributions when the building behaves as a unit or any portion is overloaded. A typical 5:12 sloped low-rise residential building is chosen as the prototype and analyzed under wind pressures measured in the wind tunnel. The structural connections, including the frame-to-frame connections and sheathing-to-frame connections, are modeled extensively to represent the critical structural details that secure the load paths for the entire building system as well as the boundary conditions provided to the building envelope. The nail withdrawal, the excessive displacement of sheathing, the nail head pull-through, the sheathing in-plane shear, and the nail load-slip are found to be responsible for the building envelope damage. The uses of the nail type with a high withdrawal capacity, a thicker sheathing panel, and an optimized nail edge distance are observed to efficiently enhance the building envelope performance based on the present numerical damage predictions.

• International Journal of Human Ecology
• /
• v.12 no.1
• /
• pp.75-85
• /
• 2011

This study aims to understand the experiences as consumers of Thai students studying in Korea. "Study Korea Project" which is a drive to globalize local universities by attracting more oversea students as a pull factor, and economic growth, values on education and Hallyu as push factors contribute to the increase the number of Thai students in Korea. In order to understand the experiences of Thai students as consumers studying in Korea, individual interviews were conducted. A total of 5 participants were asked about meaning of consumption in everyday life in Korea or any changes in consumption behavior compared to living in Thai. Three themes were identified through wholistic and selective approaches. First, all participants in the study said that they were surprised because of high living expense in Korea. Consequently, survival itself is too much for them and they have become more conscious of prices of goods. Secondly, since most participants in this study can control their own budget, they feel some degree of freedom and power of control of their own lives. This experience may help them to accomplish their developmental tasks during the transition to adulthood. Thirdly, they are easily imbued with Korean consumer culture. It causes various conflicts between buying and not-buying or friends gathering and saving money. Sometimes it makes them in stuck excessive consumption and financial problems. For a deeper understanding of oversea students' lives in Korea as consumers, further studies should take into consideration of not only their culture of origins, but also misconceptions that have accumulated around these students.

• Journal of Mechanical Science and Technology
• /
• v.20 no.7
• /
• pp.1030-1042
• /
• 2006

An experimental study has been performed to investigate the off-take phenomena at the header-feeder systems (horizontal header pipe with multiple feeder branch pipes) in a CANDU (CANadian Deuterium Uranium) reactor with the branch orientation varies ${\pm}36^{\circ}\;or\;{\pm}72^{\circ}$. In order to evaluate the applicability of the conventional correlations used in the safety analysis code, RELAP5-Mod3, the test facility is designed with the 1/2 scale of the. CANDU 6. It was found that the data set for the top, bottom and side branches are in a good agreement with the correlations used. However, for the specific angled branches, ${\pm}36^{\circ}\;and\;{\pm}72^{\circ}$, the onsets of off-take data and quality data showed large deviation with the conventional model inside RELAP5-MOD3. Furthermore, based on the uncertainty analysis, the conventional 2.5 power law needs to be modified. The present experimental data set can be useful for the construction of the general correlation considering the arbitrary branch orientation.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1997.04a
• /
• pp.794-798
• /
• 1997

We provide a set of information on technologies to draw meaningful action plans for the inter- nationalization of National R&D activities. In this study, we employed a modified Delphi method to evaluate level od our technological capabilities and developed countries' as well. We investigated technology acquistion methodologies,technology characteristics and various aspects of international cooperation in terms of technology. Then we analyzed final responses of participants (i.e, the third round results of Delphi method) to see the correlation among various factors in developing tehnologies through international R&D cooperation. The technology classification used in this research was developed by STEPI (Science and Technology Policy Institute). In conclusion, levels of our technologies were investigated to be between the stage of imitating/absorbing advanced technologies and the stage of digesting acquired technologies. Especially, comparing with other technologies, mechanical engineering was evaluated to be almost near the stage of digesting acquired technology (the middle level stage of technology). Out overal technological capabilites were evaluated to be 40~60% of top level countries'.