• KSCE Journal of Civil and Environmental Engineering Research
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• v.14 no.5
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• pp.1055-1067
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• 1994

This paper is presented to perform linear dynamic analysis of bridges due to vehicle moving on bridges. The road surface roughness and bridge/vehicle interaction are also considered. The bridge and vehicle are modeled as 3-D bridge and vehicle model, respectively. The road surface roughness of the roadway and bridge decks are generated from power spectral density(PSD) function for good road. The PSD function proposed by C.J. Dodds and J.D. Robson is used to describe the road surface roughness for good road condition. The vehicles are modeled as two nonlinear vehicle model with 7-D.O.F of truck and 12-D.O.F of tractor-trailer and the equations of motion of the vehicles are derived using Lagrange's equation. The main girder and concrete deck are modeled as beam and shell element, respectively and rigid link is used between main girder and concrete deck. The equations of motion of the vehicles are solved by Newmark ${\beta}$ method and the equations of the motion of the bridges are solved by mode-superposition procedures. The validity of the proposed procedure is demonstrated by comparing the results with the experimental data reported by the AASHO Road Test. The comparison shows that the agreement between experiment and theory is quite satisfactory.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.5
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• pp.715-722
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• 2013

Gas insulated switchgear is large-sized electric equipment for providing a reliable supply of electric power. Recently, seismic tests of electric equipment using a shaking table have been mandated because seismic performance has become an increasingly important issue. However, basic analysis methods continue to be used because some electric equipment is too large for shaking table facilities. Thus, a reliable analysis method should be developed for large-scale electric equipment. This study aims to evaluate the seismic qualification of a 245kV GIS in accordance with IEEE-693 and to validate the analysis method by comparing it with test results. Both the test and the analysis showed that the 245kV GIS has proper seismic safety. Furthermore, the differences between the analysis and the test results are less than 10% for an accurately given mass, stiffness, and input acceleration. It is expected that this study can be used for the seismic qualification of large-scale electrical structures.

• Archives of Reconstructive Microsurgery
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• v.6 no.1
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• pp.73-79
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• 1997

Complete denervation after severe brachial plexus injury make significant muscle atrophy with loss of proper function. It is much helpful to reconstruct the essential function of the elbow flexion movement in patient with total loss of elbow flexion motion after brachial plexus lesion which was not recovered with nerve surgery or long term conservative treatment from onset. In whole arm type brachial plexus injury, if there were no response to neurotization or neglected from injury, the volume of the denervated muscle is significantely reduced month by month. About 18 months most of the muscle fibers change to fibrous tissues and markedly atrophied irreversibly, further waiting is no more meaningful from that period. Authors performed 14 cases of functioning gracilis muscle transfer from 1981 to 1995 with microneurovascular technique, neuromusculocutaneous free flaps were performed for reconstruction of lost elbow flexion function. Average follow-up period was 5 years and 6 months. We used couple of intercostal nerves as a recipient nerve which were anastomosed to muscular nerve from obturator nerve in all cases. Recipient vessels were three deep brachial artery and eleven brachial artery which were anastomosed to medial femoral circumflex artery with end to end or end to side fashion. Average resting length of the transplanted gracilis were 24 cm. We can get average 54 degree flexion range of elbow with fair muscle power from flail elbow. There were one case of muscle necrosis with lately developed thrombosis of microvascular anastomosed site which comes from insufficient recipient arterial condition, 3 cases of partial marginal necrosis of distal skin of the transplanted part which were not significant problem with spontaneously solved with time goes by gracilis muscle has constant neurovascular pattern with relatively easy harvesting donor with minimal donor morbidity. Especially it has similar length and shape with biceps brachii muscle of upper arm and longer nerve pedicle which can neurorrhaphy with intercostal nerve without nerve graft if sufficient mobilization of the nerves from both sides of gracilis and intercostal region. Authors can propose gracilis muscle transplantation with intercostal nerves neurotization is helpful method with minimal donor morbidity for neglected brachial plexus palsy patients.

• Fire Science and Engineering
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• v.30 no.6
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• pp.48-56
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• 2016

A crude oil leakage from a large atmospheric storage tank occurred on 4 April 2014 at 14:50 in Ulsan City, while storing the crude oil in the tank. Emergency Rescue Control Group was deployed in the scene. The company, Fire Service Headquarters and associated agencies got together in Command Post (CP) for discussing an effective corresponding strategy. Many solution plans were drafted in the debate such as power down, stopping the facilities, checking the density of inflammable gas, suppressing oil evaporation, moving the leaked crude oil to a nearby tank and a processing plant and avoiding marine pollution. All the solutions were carried out in cooperation with several agencies and partners. The oil leakage accident was successfully settled up within the process of responding, The Fire Service Headquarters and the company thought that the most important thing was the suppression of oil evaporation and the elimination of ignition source. With Fire Service Headquarters and several agencies' every effort, an explosion and a fire didn't occurred in the scene. This study suggest the improvement of the operating system in Emergency Rescue Control Group in case of petroleum leakage, explosion and fire accidents of atmospheric storage tank, different from a ordinary disaster. Assuming that petroleum leakage in atmospheric storage tank develop the explosion and fire accidents, the spreading speed of the flame and the burning time was experimented and compared with each other. Furthermore, this study concentrates on the effective field response plan prepared for the afterward explosion and fire accidents from petroleum leak in a storage tank, with the database experimented and analyzed in accordance with the angle of radiation in the foam nozzle and the pressure of pumping in a fire engine.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.26 no.6
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• pp.439-445
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• 2013

The soil-structure interaction(SSI) effect should be considered to accurately assess the seismic response of structure constructed on soft soil site other than the hard bedrock. Recently, the demand of SSI analysis has increased due to strengthening of the regulatory guidelines of nuclear power plant such as the USNRC SRP 3.7.2. In this study an accuracy and running time of the KIESSI-3D program for large-scale 3D SSI analysis were investigated. The seismic SSI analysis using the KIESSI-3D program was performed for several examples of large-scale three-dimensional soil-structure interaction system. The analysis results were compared with those of the ACS/SASSI program. Good agreements in transfer functions at selected locations showd that KIESSI-3D yields accurate solution for large-scale SSI problem. Moreover, it was found that running speed of the KIESSI-3D for large-scale 3D SSI analysis is much faster than that of the ACS/SASSI about 30~2000 times.

• Korean Journal of Optics and Photonics
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• v.5 no.3
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• pp.423-430
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• 1994

We designed and fabricated the single mode fiber pigtailed DFB-LD module for 2.5 Gbps optical communication system. In the design of the DFB-LD module, we made the module divided into two parts of inner sub-module and outer 14-pin butterfly package and cylindrical shaped sub-module contain quasi confocal 2 lens system including optical isolator and electrical connection between these parts via hybrid substrate of bias T circuit. Laser welding was used to assemble the sub-module which requires accurate fixing between optical elements. The fabricated DFB-LD module showed optical coupling efficiency of 20% and - 3 dB small signal response of more than 2.6 GHz. We confirmed mechanical reliability of the module by temperature cycle test where the tested module exhibit optical power fluctuation of less than 10%. Finally we evaluated the performance of the fabricated DFB-LD module as light source of 2.5 Gbps optical communication system, sensitivity of - 30.2 dBm was obtained through 47 km optical fiber transmission under the criterion of $1\times10^{-10}$ BER and transmission penalties were 1.5 dB caused by extinction ratio and 1.0 dB caused by chromatic dispersion of normal single mode fiber. fiber.

• Journal of Korean Society of Steel Construction
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• v.22 no.4
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• pp.325-334
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• 2010

In this study, an unbraced five-story steel-framed structure was designed in accordance with KBC2005 to understand the features of structural behavior for the arrangement of semi-rigid connections. A pushover analysis of the structural models was performed, wherein all the connections were idealized as fully rigid and semi-rigid. Additionally, horizontal and vertical arrangements of the semi-rigid connection were adopted for the models. A fiber model was utilized for the moment-curvature relationship of the steel beam and the column, and a three-parameter power model was adopted for the moment-rotation angle of the semi-rigid connection. The top displacement, base-shear force, required ductility for the connection, sequence of the plastic hinge, and design factors such as the overstrength factor, ductility factor, and response modification coefficient were investigated using the pushover analysis of a 2D structure subjected to the equivalent static lateral force of KBC2005. The partial arrangement of the semi-rigid connection was found to have secured higher strength and lateral stiffness than that of the A-Semi frame, and greater ductility than the A-Rigid frame. The TSD connection was found suitable for use for economy and safety in the sample structure.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.40 no.4
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• pp.311-318
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• 2004

It is very important for the safe navigation and fishing operation to ensure the hull response of a fishing vessel in rough seas. This is an experimental study on the dynamical characteristics of ship's motion during operating job and sailing in the real sea. The experiments were carried out on the small stern trawler in operating job and sailing, and then the ship's roll and pitch motion were simultaneously recorded by P/C according to the wave directions. From these data, the statistical properties and power spectra were obtained and the analysis of ship's motions in the both case were made. The results obtained are summarized follows : (1) The amplitudes of pitch motion don't appear a big different between trawl job and sailing, but at bow seas, its in sailing have a tendency to increase more than in trawl job. The amplitudes of roll motion appear a bog different between trawl job and sailing, but at beam sea, that slightly decreasing tendency. (2) The peak period of pitch motion in trawl job and sailing change, but that of roll motion don't change according to the direction of waves. (3) The warp tention cause the motion of hull to be reduce, if the tention of each side have a ballance.

• The Journal of the Korean bone and joint tumor society
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• v.3 no.1
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• pp.18-25
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• 1997

Prosthetic replacement is one of the most common methods of reconstruction after resection of malignant tumor around the knee. Gait analysis provides a relative objective data about the gait function of patients with prosthesis. The purpose of this study was to compare the gait pattern of the patients who underwent limb salvage surgery with prosthesis for distal femur and that of patients with prosthesis for proximal tibia. This study included ten patients (4 males, 6 females, mean age 22.7 years, range 14-36) who underwent a wide resection and Kotz hinged modular reconstruction prosthesis replacement and six normal adult(Control). The site of bone tumor was the distal femur (Group 1) in six patients and proximal tibia (Group 2) in 4 patients. The follow-up period ranged from 15 to 82 months (mean : 33 months). The evaluation consisted of clinical assessment, radiographic assessment, gait analysis using VICON 370 Motion Analysis System. The gait analysis included the linear parameters such as, walking velocity, cadence, step length, stride length, stance time, swing time, single support and double support time and the three-dimensional kinematics (joint rotation angle, velocity of joint rotation) of ankle, knee, hip and pelvis in sagittal, coronal and transverse plane. For the kinetic evaluation, the moment of force (unit: Nm/kg) and power (unit: Watt/kg) of ankle, knee and hip joint in sagittal, coronal and transverse plane. In the linear parameters, cadence, velocity, step time and single support were decreased in both group 1 and group 2 compared with control. Double support decreased in group 2 compared with control significantly(p<.05). In contrast to our hypothesis, there was no significant difference between group 1 and group 2. In Kinematics, we observed significant difference (p<.05) of decreased knee flexion in loading response (G2

• The Korean Journal of Emergency Medical Services
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• v.8 no.1
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• pp.117-126
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• 2004

In general, the patients who transferred to the hospital by 119 rescue service at night go to the emergency room(ER) of general hospital rather than that of their nearby the 1st(clinic) and 2nd(local hospital) hospital. And the hospital is mainly selected not by 119 EMST but by patients or his/her conservators. Therefore we had studied retrospectively with emergency situation diary and medical chart for 697 patients of being transferred to one emergency medical center for 6 months since January 2004, and results are as follows. 1. The 280 patients(42.5%) of being transferred hospital at night by 119 rescue service were not emergency case and their average staying time in hospital was about $7.15{\pm}10.06$ minutes. 2. Transfer time was distributed in each time intervals of 1819, 2021, 2223, and 2401 and patients ratio in each intervals were 15.1%, 17.8%, 16.4%, and 15.2%. 3. In response of ambulance, the average time from the spot to the hospital was $14.53{\pm}9.27min$. and average distance of that was $7.95{\pm}9.21km$. 4. Diseases rather than traffic accidents or traumatic injury were main causes of ambulance calling and its value was 533(76.5%), and accidents were mainly occurred in patients' house and its value was 479(68.7%). 5. In time of transfer by 119 rescue service, hospital was mainly selected by patient/conservator and its value was 648(93.0%). In result. the hospital was selected not by EMST but by patient/conservator. 6. The case that the 1st grade EMT was rode in ambulance was 161(23.1%), and the case that 2nd EMT and emergency team member who educated for emergency were rode in ambulance were 504(72.3%). So the number of the 1st grade EMT was short in fire station of Kwangju metropolitan city than other city. 7. The first aids for patients before reaching hospital were limited to oxygen inhalation, airway control, and BLS for maintaining limbs and spine. So it seems to be a simple patients transfer. Consequently, to establish an efficient emergency medical system, it has been thought that it should be advanced a moderate education and public information about the appropriate use of emergency medical system toward citizen, and also need the hospital selection by the patients categorizing standards for 119 rescue service member, securing the 1st grade EMT, appropriate first-aids education, and securing professional human power in emergency room of the Ist(clinic) and 2nd(local hospital) hospital at night.