• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.8
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• pp.857-863
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• 2012

In this study, tailor-welded blanks(TWB) were formed between high-strength steel(SABC1470) and cold rolled steels(SPFH590 and SPFC980) to improve passenger safety and reduce the weight of cars. Multi-material TWB specimens were highly strengthened through the heat treatment of SABC1470. The change in tensile strength caused by the stand-by time until water cooling after stamping and the deformation behavior of high-speed bending in a statically indeterminate condition such as in the center-pillar were evaluated. Multi-material TWB specimens that were heat-treated at the same temperature tended to show a decrease in tensile and yield strength, depending on the stand-by time until water cooling. On the other hand, Multi-material TWB specimens(SABC1470+SPFH590) that were heat treated at $850^{\circ}C$ showed good properties that were suitable for ensuring passenger safety in car accidents. From the viewpoint of passenger safety, it is best to use SABC1470 and SPFH590 in the upper and lower area of the center-pillar, respectively.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.38 no.12
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• pp.1367-1372
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• 2014

As the awareness of the environmental crisis has recently increased around the world, numerous studies in the transport industry have been conducted to solve this problem through lightweight car bodies. The hot-stamping process has been presented as solution to achieve a light weight. Hot-stamping is a method that is used to obtain ultra-high strength steel (1,500 MPa or greater) by simultaneously forming and cooling boron steel in a press die after heating it to a temperature of $900^{\circ}C$ or above. This study involved a, fundamental examination of laser parameters to investigate the laser weldability of boron steel. As a result, the following optimum parameters for the shielding gas were found: Q = 20 l/min, ${\alpha}=40^{\circ}$, d = 20mm, and l = 0 mm. The hardness of butt weldment increasesed sharply as a result of martensite formation at the fusion zone.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.10
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• pp.547-557
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• 2020

In this study, damping control devices were applied to the suspension system of a capsule train, and the effects were investigated to improve the ride comfort. The superconductor electrodynamic suspension (SC-EDS) method is used for the capsule train levitation. This method has advantages such as no gap control and a large gap. However, the SC-EDS method has disadvantages such as large gap variation and small damping characteristics against outer vibration, which causes degradation of the ride comfort. In this study, the damping control devices in the primary and secondary suspension were considered to improve the ride comfort in the capsule train. Damping control devices in the primary and secondary suspension can reduce the vibration transmission from outer disturbances to the bogie and from the bogie to the car body, respectively. Simulations for dynamic characteristics analyses were conducted based on the capsule train dynamic model to investigate the effects of the damping control devices on the ride comfort. As a result, it was confirmed that the ride comfort requirements according to the ISO standard can be satisfied by applying the damping control in the capsule train suspension.

• Land and Housing Review
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• v.7 no.3
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• pp.131-136
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• 2016

The aim of this study was to improve the performance of hybrid energy harvesting block merge the vibrations and the pressure developed in the previous study. The power generation performance of the energy block improved in this manner was measured and compared with the energy performance of the products previously developed. In previous models, the center has placed a piezoelectric, the two sides had arranged a vibration applying electromagnetic inducing type. Improved model was disposed three in a row of three unit modules for one block. We change the design in the following way. That is, a unit module has been placed the upper piezoelectric body, the lower portion were arranged three electron donation. In laboratory conditions, the power generation performance evaluation results of the improved energy block is as follows. Once when the vibration, power generation was determined to 1.066W. When compared with previous studies, and power generation performance is improved up to 235%. When the vibration in a row 5, power generation was determined to 1.830W. When compared with previous studies, the performance is improved to 177%. The purpose of developing a hybrid energy block is intended to produce electricity by the pressure and vibration when a vehicle passes through the energy block installed in the car park the mouth portion. Electricity produced will try to take advantage of for the purpose of operating a guiding beacon and LED signage in the parking lot entrance. Therefore, it is determined that there is a need in the experiment to compare the performance of the power generation in the field.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.10
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• pp.4536-4542
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• 2011

RFID technology uses communication through the use of radio waves to transfer data between a reader and an electronic tag attached to an object for the purpose of identification and tracking. RFID technology can be applied to the various service areas such as, position determination technology, remote processing management and information exchange between objects by collecting, storing, processing, and tracing their informations from the tag attached to the objects using electronic wave by recognizing the information and environment of those objects. However, to revitalize these various services, it is important to test the RFID tag performance. But There are few instructions which have and hold the RFID emulator technology for organizing the RFID international test environment. Also there are not many manufacturing companies which recognize about the exact RFID test standard and requirements for the International Standards. In this paper, a construction of Tag Performance test environments and test methods are suggested which are required by EPCglobal or ISO/IEC. Details about RFID Tag performance test items proposed by ISO/IEC FDIS 18046-3 are explained, performed RFID Tag performance test through the performing test against each measured item, and draw a result for the RFID Tag performance of International Standards.

• The Journal of Churna Manual Medicine for Spine and Nerves
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• v.8 no.1
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• pp.27-38
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• 2013

Objectives : The purpose of this study is to investigate the latest trends of korean Medicine treatments on traffic accident for recent 5 years. Methods : We investigated the studies on korean Medicine treatments for traffic accident via searching 6 Korean web databases. As a result, 65 research papers were found to be analyzed according to their published year, the titles of journals, the types of study, the number of cases, the sites of injury, the types of treatments the instruments for assessment and ethics approvals. Results : 65 articles were published since 2008. The studies on korean Medicine treatments about traffic accident were mainly published in Journal of Oriental Rehabilitation Medicine. 10 case studies, 14 case series, 11 non randomized controlled trials, 21 randomized controlled trials and 9 systemic reviews had been under research. The most frequently occurred symptoms were neck pain and low back pain. In most studies, various korean Medicine treatments were used to treat the symptoms. Visual analogue scale(VAS) and neck disability index(NDI) were used as primary assessments. In most clinical studies, there were no mention about approval of institutional review board(IRB). Conclusion : In this study, we analyzed the trends of korean Medicine treatments on traffic accident from 2008 to 2012. Reviewing the domestic trends of studies on korean Medicine treatments for traffic accident and examining the strong and weak points of those treatments are essential for the future studies. It is needed to adopt the qualitative methods of evaluation in order to develop a level of evidence.

• Journal of the Korea Organic Resources Recycling Association
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• v.4 no.2
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• pp.55-62
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• 1996

The purpose of this study is the evaluation of adsorption capacity of casts for heavy metals comparing with the activated carbon. The casts was obtained from vermicomposting of the mixed organic sludges which were generated from the treatment facilities for leather wastewater and cattle wastewater. The physico-chemical characteristics of cast was investigated. Also, the batch adsorption experiments of cast and activated carbon for heavy metals were carried out, and the results were analyzed by Freundlich isotherm. The buffering capacity to the acidic wastewater was founded in the cast, and the cation exchange capacity of cast impling adsorption capacity for soluble substances was evaluated as about 55me/100g. Those were implied that the cast have a large potential as a good adsorbent for soluble pollutants in wastewater. From the results of batch experiments, the removal efficiencies of tested various heavy metals including Pb, Cu, Cd, and Cr were very high value as 89-98% for the activated car-bon, and 80~95% for the casts except for Zn. The adsorption equilibriums for the two materials were achieved within 90 minutes. The order of preferable metals in the adsorption was found to be Pb>Cu>Cd>Cr>Zn on the cast and to be Pb>Cd>Cu>Cr>Zn on the activated carbon, respectively. From the above results, it might be con-cluded that cast is effectively available as a good adsorbent to treating the heavy metal bearing wastewater.

• Journal of Korean Society of Transportation
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• v.33 no.4
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• pp.323-336
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• 2015

Estimating the risks on the roadway using surrogate safety measures (SSM) has an advantage in that it focuses on the vehicle trajectory directly involved in conflicts. On the other hand, there is a restriction on estimating the risks of continuous segments due to the limited data collected from a location. To overcome the restriction, this study presents the scheme of acquiring the vehicular trajectory using real time kinematics-differential global positioning system (RTK-DGPS) and develops a methodology which contains the considerations of the problems to calculate the SSM such as time-to-collision (TTC), deceleration rate to avoid collision (DRAC) and acceleration noise (AN). By using the methodology, this study shows a result from an experiment executed in a section where the variation of vehicular movement can be observed from several continuous flow roadway sections near Seoul and Gyeonggi Province in Korea. The result illustrated the risks on the roadway by the SSM metrics in certain situations like merging and diverging, stop-and-go, and weaving. This study would be applied to relate the dangers with characteristics of drivers and roadway sections, and prevenst accidents or conflicts by detecting dangerous roadway sections and drivers' behaviors. This study contributes to improving roadway safety and reducing car-accidents.

• Radiation Oncology Journal
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• v.8 no.1
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• pp.1-6
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• 1990

In the present study, a perfluorchemical emulsion (Fluosol-DA $20\%$) did not alter $D_o\;and\;D_q$ values on cell survival curve, indicating that the lack of a direct effect of Fluosol-DA $20\%$ on cellular radiosensitivity in vitro. The effect of Fluosol-DA $20\%$ injection in combination with carbogen breathing was determined on the hypoxic cell fraction in SCK tumors. The hypoxic cell fraction in control SCK tumors was 0.39. This value decreased to 0.05 when the mice were i.v. injected with 12 ml/kg of Fluosol-DA $20\%$ in a carbogen atomosphere. The measured mean and median $PO_2$ values with a microelectrode in the control tumors was 9 mmHg and 4 mmHg, respectively. The treatment of the SCK tumors in the host mice with injected Fluosol-DA $20\%$ in combination with carbogen breathing increased the mean and median $PO_2$ values to 67 mmHg and 62 mmHg, respectively. Using carbogen breathing alone caused a moderate increase of tumor $PO_2$. But Fluosol-DA $20\%$ injection alone caused little change $PO_2$ in the tumor. It was concluded that the combination of Fluosol-DA injection and carbogen breathing is an effective means to improve oxygenation of tumors.

• Journal of Chest Surgery
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• v.43 no.1
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• pp.104-107
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• 2010

Acute respiratory distress syndrome (ARDS) is difficult to treat and it is often fatal. If the medical treatment for ARDS is not effective, then extracorporeal membrane oxygenation (ECMO) can be applied to the patient. A 22-year-old female who suffered multiple traumatic injuries due to a car accident presented with acute respiratory distress syndrome. Veinarterial extracorporeal membrane oxygenation (VA ECMO) was started to treat her respiratory failure. With the VA ECMO, the systemic oxygen saturation remained at only 84%, and so the ECMO system was switched to V-VA ECMO via an additional venous outflow through the right jugular vein to increase both the systemic and pulmonary oxygen saturation. After conversion to the V-VA type ECMO, the systemic oxygen saturation increased to 94% and the partial pressure of oxygen ($PaO_2$) increased to 65 mmHg. We report here on a successful case of ECMO conversion from the VA type to the V-VA type in a patient with severely hypoxic respiratory failure.