• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.5
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• pp.943-951
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• 1992

The objectives of this study are to analyse the thermal response behavior occurring in the charring ablative material more realistically by considering ablation and char phenomena occurring in several material layers, and to increase the reliability of thermal analysis by being able to get stable solutions through using the finite analytic method. A program has been developed to predict the temperature distribution, ablation thickness, char thickness, ablation velocity and char velocity by solving non-linear one-dimensional heat conduction equation. Results of calculation were compared with results of published papers. From this compariosn this program was proved to be a very good tool for thermal design and analysis of charring ablative materials used in the rocket propulsion system.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.24 no.1
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• pp.43-48
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• 2015

Silver nanowire (AgNW) is a material that is increasingly being used for transparent electrodes, as a substitute for indium tin oxide (ITO), owing to its flexibility, high transmittance to sheet resistance ratio, and simple production process. This study involves manufacturing large-area organic photovoltaic cells (OPVs) deposited on AgNW electrodes. We compared the efficiency of OPVs with ITO and AgNW electrodes. The results verified that an OPV with an AgNW electrode performed better than that with an ITO electrode. Furthermore, by using the knife coating method, we successfully fabricated large-area OPVs without the loss of efficiency. Use of AgNW instead of ITO demonstrated that an OPV could be produced on various substrates by the solution process method, dropping the productions costs significantly. Additionally, by using the knife coating method, the process time and amount of wasted solution are reduced. This leads to an increase in the efficient fabrication of the OPV.

• Computers and Concrete
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• v.21 no.5
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• pp.495-504
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• 2018

The possibility of earthquakes in vulnerable regions indicates that efficient technique is required for seismic protection of buildings. During the recent decades, the concept is moving towards the insertion of base isolation on seismic prone buildings. So, investigation of structural behavior is a burning topic for buildings to be isolated in base level by bearing device. This study deals with the incorporation of base isolation system and focuses the changes of structural responses for different types of Lead Rubber Bearing (LRB) isolators. A number of sixteen model buildings have been simulated selecting twelve types of bearing systems as well as conventional fixed-base (FB) scheme. The superstructures of the high-rise buildings are represented by finite element assemblage adopting multi-degree of freedoms. Static and dynamic analyses are carried out for FB and base isolated (BI) buildings. The dynamic analysis in finite element package has been performed by the nonlinear time history analysis (THA) based on the site-specific seismic excitation and compared employing eminent earthquakes. The influence of the model type and the alteration in superstructure behavior of the isolated buildings have been duly assessed. The results of the 3D multistory structures show that the lateral forces, displacement, inertia and story accelerations of the superstructure of the seismic prone buildings are significantly reduced due to bearing insertion. The nonlinear dynamic analysis shows 12 to 40% lessening in base shear when LRB is incorporated leading to substantial allowance of horizontal displacement. It is revealed that the LRB isolators might be potential options to diminish the respective floor accelerations, inertia, displacements and base shear whatever the condition coincides. The isolators with lower force intercept but higher isolation period is found to be better for decreasing base shear, floor acceleration and inertia force leading to reduction of structural and non-structural damage. However, LRB with lower isolator period seems to be more effective in dropping displacement at bearing interface aimed at reducing horizontal shift of building structure.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.2
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• pp.725-729
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• 2014

Background: Having been known as a virulent disease in 1970s, cancer is now onsidered a chronic disease and 64% of cancer patients live for five years after diagnosis. Home care has gradually gained more importance and it is a great burden on the shoulders of caregivers. Caregivers have to undertake the responsibility of the cancer patient's home management, and organize care and arrange health care services according to the ever-changing condition of patients. Caregivers should be prepared for home care so they can provide accurate and complete care to patients. This descriptive study aims to investigate challenges that caregivers encounter in the home care of patients and the reasons for these challenges. Materials and Methods: The research group consisted of caregivers of outpatients in a daily treatment center in a university hospital. The research sampling consisted of 137 voluntary caregivers of patients who attended the Daily Treatment Center for control, chemotherapy or other supportive cares services between January-June, 2011. Data were collected with face-to-face interviews in the Daily Treatment Center. Ethics Committee approval was taken university hospital; caregivers and their patients were informed about the research and their approval was taken as well. Results: It was found that 54.01% of caregivers help patient's nutrition, 50.36% help medicine use, 26.28% help oral hygiene, 26.28% help to meet urinary needs and 51.82% help to change clothes, 69.34% of caregivers help to change bed sheets, 38.69% help the patient to communicate with their environment and 71.53% help to bring the patient to hospital or outside. Conclusions: This study, it was found that caregivers experience challenges due to following factors: patient nutrition, medicine use, oral and body hygiene, colostomy maintenance and stomach tube feeding, concern of dropping the patient, feeling incompetency in body temperature and fever control, fatigue, and lack of personal time.

• Journal of Korean Society for Geospatial Information Science
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• v.20 no.1
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• pp.101-107
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• 2012

Urban area is being continuously grown traffic volume due to diverse economic activities. Especially, the traffic noise, which occurs on the road of passing by residential district, is dropping quality of life as negative element of obstructing sleep at night. This study analyzed relationship between the officially notified land price and the traffic noise in residential district by using the estimating equation of traffic noise and GIS. As a result, the officially notified land price on a parcel of residential district along the road was indicated to be higher than a parcel where is located in other place. Even traffic noise was indicated to be higher. Accordingly, a plan is judged to be necessarily arranged that can be made appraisal of the officially notified land price, which is reflected the convenience of life and the quality of life at the same time in consideration even of traffic noise together as element of appraisal given evaluating the officially notified land price in residential district where is located in the downtown.

• Journal of Korea Multimedia Society
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• v.7 no.7
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• pp.905-912
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• 2004

It is a study LVMPD to solve the fairness problem of inter-session shared bandwidth. Whenever congestion occurs in one session, the highest layer is dropped. Also the highest layer of other sessions in non-congestion is dropped by iner-session fairness. While there is spare bandwidth, receivers of session in non-congestion can't use bandwidth efficiently. In this paper, we proposed a distribution method to use efficiently spare bandwidth that occurred by inter-session fairness. In our method, we considered the highest layer those receivers receiving and the higher layer those receivers requesting. The sender assigns the packet-deleting priority to packets when congestion occurs in receivers, and sets layer add/drop flag when receivers of session in non-congestion request the higher layer. The switch deletes packets with packet-deleting priority and transfers packets with layer add/drop flag for session in non-congestion. Therefore receivers of session in non-congestion can add the higher layer. In experimental results, it was known that proposed algorithm use the inter-session shared bandwidth more effectively compared with already known method.

• KSBB Journal
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• v.23 no.1
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• pp.59-64
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• 2008

Optimum conditions for production of casein phosphopeptides (CPP) from sodium casenate by immobilized cell culture of Streptococcus faecalis var. liquefaciens were investigated. Immobilized cells were made by mixing 60% sodium alginate solution with an equal volume of culture broth at the end of exponential phase and subsequently dropping the mixture into $CaCl_{2}$ solution. Optimum conditions for CPP production by the immobilized cells were the same as those ($50^{\circ}C$, pH 7.0, and 10% substrate concentration) by the crude enzyme solution from the supernatant of culture broth. Optimum loading volume of the immobilized cells into a batch reactor was 30% (w/v). Using a continuous reactor loaded by the immobilized cells under the identified optimal conditions, we were able to produce CPP continuously up to 30 days with a maximum CPP conversion efficiency of 20%.

• Korean Chemical Engineering Research
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• v.58 no.2
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• pp.286-292
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• 2020

This study presents an angular-based measurement on three-dimensional paper-based analytical devices (3D-PADs) for quantitative detection of albumin without using an image analyzer. We demonstrate a simple quantitative and straightforward approach based on the angle of the discolored area as detection criteria. 3D-PADs are rapidly fabricated by the wax-printing and laminating process. The 3D-PADs are treated with citrate buffer and tetrabromophenol blue to react with albumin in a sample solution. Dropping sample solution into sample pad in the 3D-PAD, fluid flows toward the assay zone laterally and vertically by capillary action. We find that the change of angle of the discolored area correctly reflects the concentration of albumin and is reliable determinant for the measurement of the albumin concentration. It is the first demonstration of angular-based detection as a simple, inexpensive, and equipment-free approach for point-of-care diagnosis.

• Advances in Traditional Medicine
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• v.7 no.5
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• pp.556-563
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• 2008

Peripheral nerve injuries are a commonly encountered clinical problem and often result in a chronic pain and severe functional deficits. The expression of c-Fos is sometimes used as a marker of increased neuronal activity. We have prepared the aqueous extract of amygdalin from Armeniacae semen for pain control. In the present study, we investigated the effects of amygdalin on the recovery rate of the locomotor function and on the expression of c-Fos in the ventrolateral periaqueductal gray (vlPAG) region following sciatic crushed nerve injury in rats. Walking track analysis for the evaluation of functional recovery and immunohistochemistry for the c-Fos expression were used in this study. In the present results, characteristic gait change with dropping of the sciatic function index (SFI) was observed and c-Fos expression in the vlPAG was suppressed following sciatic crushed nerve injury in rats. Amygdalin enhanced SFI value and restored c-Fos expression in the vlPAG to the control value. The present our study indicated that amygdalin activates neurons in the vlPAG, and it facilitates functional recovery following peripheral nerve injury.

• The Korean Journal of Physiology and Pharmacology
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• v.12 no.6
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• pp.299-306
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• 2008

Sometimes, spinal cord injury (SCI) results in various chronic neuropathic pain syndromes that occur diffusely below the level of the injury. It has been reported that behavioral signs of neuropathic pain are expressed in the animal models of contusive SCI. However, the observation period is relatively short considering the natural course of pain in human SCI patients. Therefore, this study was undertaken to examine the time course of mechanical and cold allodynia in the hindpaw after a spinal cord contusion in rats for a long period of time (30 weeks). The hindpaw withdrawal threshold to mechanical stimulation was applied to the plantar surface of the hindpaw, and the withdrawal frequency to the application of acetone was measured before and after a spinal contusion. The spinal cord contusion was produced by dropping a 10 g weight from a 6.25 and 12.5 mm height using a NYU impactor. After the injury, rats showed a decreased withdrawal threshold to von Frey stimulation, indicating the development of mechanical allodynia which persisted for 30 weeks. The withdrawal threshold between the two experimental groups was similar. The response frequencies to acetone increased after the SCI, but they were developed slowly. Cold allodynia persisted for 30 weeks in 12.5 mm group. The sham animals did not show any significant behavioral changes. These results provide behavioral evidence to indicate that the below-level pain was well developed and maintained in the contusion model for a long time, suggesting a model suitable for pain research, especially in the late stage of SCI or for long term effects of analgesic intervention.