• Steel and Composite Structures
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• v.24 no.5
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• pp.561-568
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• 2017

Steel frames are widely used in steel structures. Exiting steel structures may be needed to strengthen for various reasons. Carbon Fiber Reinforced Polymers (CFRP) is one of the materials that are used to strengthen steel structures. Most studies on strengthening steel structures have been done on beams and steel columns. No independent study, to the researcher's knowledge, has studied the effect of CFRP strengthening on steel frames. This study explored the use of CFRP composite on retrofitting square hollow section (SHS) steel frames, using numerical investigations. Ten Finite Element (FE) models, which were strengthened with CFRP sheets, were analyzed under different coverage length, number of layers, and location of CFRP composite. One FE model without strengthening was analyzed as a control FE model to determine the increase of the ultimate load in the strengthened steel frames. ANSYS software was used to analyze the SHS steel frames. The results showed that the coverage length and the number of layers of CFRP composite have a significant effect on increasing the ultimate load of the SHS steel frames. The results also showed that the location of CFRP composite had no similar effect on increasing the ultimate load and the amount of mid span deflection of the SHS steel frames.

• Structural Engineering and Mechanics
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• v.74 no.5
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• pp.589-600
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• 2020

The bonding interface of the concrete slab track and cement-asphalt mortar layer plays an important role in transferring load and restraining the track slab's deformation for slab track structures without concrete bollards in high-speed railway. However, the interfacial bond-slip behavior is seldom considered in the structural analysis; no credible constitutive model has been presented until now. Elaborating the field tests of concrete to cement-asphalt mortar interface subjected to longitudinal and transverse shear loads, this paper revealed its bond capacity and failure characteristics. Interfacial fractures all happen on the contact surface of the concrete track slab and mortar-layer in the experiments. Aiming at this failure mechanism, an interfacial mechanical model that employed the bilinear local bond-slip law was established. Then, the interfacial shear stresses of different loading stages and the load-displacement response were derived. By ensuring that the theoretical load-displacement curve is consistent with the experiment result, an interfacial bond-slip constitutive model including its the corresponding parameters was proposed in this paper. Additionally, a finite element model was used to validate this constitutive model further. The constitutive model presented in this paper can be used to describe the real interfacial bonding effect of slab track structures with similar materials under shear loads.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.11
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• pp.6985-6989
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• 2013

Background: This study aimed to examine out-of-pocket expenditure for cancer treatments of hospitalized patients and to analyze changing patterns over time. Materials and Methods: This study examined data of all cancer patients receiving inpatient care from two tertiary hospitals from January 2003 to December 2010. Medical expenditures per admission were calculated and classified into those covered and uncovered by the Korean National Health Insurance (NHI) and co-payment. Results: The medical expenditure per admission increased slowly from 3,455 thousand Korean won (KRW) to 4,068 thousand KRW. While expenditures covered by the NHI have increased annually, co-payments have generally decreased. The out-of-pocket expenditure ratio, which means the proportion of uncovered expenditure and co-payment among total medical expenditure dropped sharply from 2005 to 2007 and was maintained at a similar level after 2007. Medical expenditures, NHI coverage, and the out-of-pocket expenditure ratio differed across cancer types. Conclusions: It is necessary to continually monitor the expenditure of uncovered services by the NHI, and to provide policies to reduce this economic burden. In addition, an individual approach considering cancer type-specific characteristics and medical utilization should be provided.

• The Research Journal of the Costume Culture
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• v.18 no.6
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• pp.1112-1128
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• 2010

This study aims to know the trace of Korean musical, consider musical depending on its type, arrange characteristic of musical costume and find out the developmental direction of Korean musical costume with potentials as a culture industry. For study method, the data were collected from thesis, academic journal, book and internet web-site concerning musical costume, literatures were considered and performance costume photos, which were captured via musical performance site, were analyzed. The history of Korean modern-day musical is regarded as starting with (1966) in the full scale. Although foreign musical was imitated in 1970s~1980s, it may be called the growth period of Korean musical because the period showed the commercial possibility. Since 1990s, large-scaled musical securing good work and popularity was popular. In 2000s, musical industry was abundant quantitatively and qualitatively as investment or popularity was significantly expanded. The type of Korean musical are divided to opera musical of European, Broadway musical of American and creative musical of Korean. The costumes used in opera musical of European and Broadway musical of American are borrowed from original works through license or were manufactured in Korea by referring to the costumes of original works and using similar materials or fabrics. The costumes used in creative musical of Korea are designed by either domestic or foreign designers and produced in Korea.

• IEMEK Journal of Embedded Systems and Applications
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• v.11 no.5
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• pp.305-312
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• 2016

Modern embedded systems are typically operated by the rechargeable batteries in our daily life. Since charge of batteries is considered as an time consuming task, there have been extensive efforts to manage the charge time from the perspective of materials, circuits, and systems. Estimation of battery charge time is one of the essential information to design the charge circuitry. A compact macro model for the constant-current and constant-voltage charge protocol was recently introduced, which gives us a quick estimation of charge time with similar shape to the famous Peukert's law for discharge time estimation. The CC-CV charging protocol is widely used for Lithium-based batteries and Lead-acid batteries. In this paper, we characterize the lead-acid battery by measurement to extract the model coefficients, which was not covered by the previous studies. By our proposed model, the key coefficient Kcc results in 1.18-1.31, which is little bit higher than that of Lithium batteries. The accuracy of our model is within the range of ${\pm}10%$ error, which is compatible with the other studies such as Peukert's law.

• Journal of international Conference on Electrical Machines and Systems
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• v.2 no.1
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• pp.57-64
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• 2013

The functional characteristic of LISN circuit, which is used for measurements of conductive noise in mains power line, is basically related to frequency characteristics of passive elements like inductors used in the circuit as well as the frequency response of inductors is highly related to the resins used in the varnishing process. The significant problem in determination of an inductor's frequency characteristic is the intrinsic resistance, inductance and parasitic capacitance. In this triplet, the parasitic capacitance is the major limiting factor of inductor's frequency range. This capacitance depends on inductor design parameters and materials filling the spaces of coil like resin and its coherency after curing process. In this paper, two similar inductors were designed and built. The first inductor was not varnished while the second one was varnished with VPI technology. VPI, or Vacuum, Pressure, Impregnation technology is one of the most reliable methods performing good insulating conditions for electrical circuits and windings based on resins. The measured results show that implying varnishing technology does not significantly affect the frequency response. However, due to mechanical solidity aspects and improved environmental protection, it is better to varnish the inductors.

• Bulletin of the Korean Chemical Society
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• v.32 no.7
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• pp.2217-2221
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• 2011

We investigated the selective deoxyribonucleic acid (DNA) adsorption on layered double hydroxide (LDH) nanoparticles via studying the interaction between positively charged LDH nanoparticle as adsorbent and negatively charged adsorbates such as methyl orange (MO), fluorescein (FL), and DNA strands. The size controlled LDH $(Mg_{0.78}Al_{0.22}(OH)_2(CO_3)_{0.11}{\cdot}mH_2O)$ was prepared by conventional coprecipitation method, followed by the hydrothermal treatment. According to the adsorption isotherms, the adsorbed amounts of MO and FL were similar, however, that of DNA were much larger. The adsorption behaviors were well fitted to Freundlich adsorption model. The concentration dependent adsorption behavior on LDH surface was described in order to verify the selective DNA separation ability. The result showed that the LDH has advantages in selective adsorption of DNA competing with single molecular anions.

• Korean Journal of Agricultural Science
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• v.47 no.1
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• pp.29-41
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• 2020

Biodiesel is a clean energy resource that can replace diesel as fuel, which can be used without any structural changes to the engine. Vegetable oil accounts for 95 percent of the raw materials used to produce biodiesel. Thus, many problems can arise, such as rising prices of food resources and an imbalance between supply and demand. Most of the previous studies using waste cooking oil used waste cooking oil from a single material. However, the waste cooking oil that is actually collected is a mixture of various types of waste cooking oil. Therefore, in this study, biodiesel produced with mixed waste cooking oil was supplied to an agricultural single-cylinder diesel engine to assess its potential as an alternative fuel. Based on the results, the brake specific fuel consumption (BSFC) increased compared to diesel, and the axis power decreased to between 70 and 99% compared to the diesel. For emissions, NO_x and CO₂ were increased, but CO and HC were decreased by up to 1 to 7% and 16 to 48%, respectively, compared to diesel. The emission characteristics of the mixed waste cooking oil biodiesel used in this study were shown to be similar to those of conventional vegetable biodiesel, confirming its potential as a fuel for mixed waste cooking oil biodiesel.

• Korean Journal of Human Ecology
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• v.9 no.3
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• pp.23-36
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• 2006

The present study purposed to examine how the knowledge, consciousness and attitude affect life resources use of the subjects, first-year middle school students and their mothers, and ultimately, to provide basic materials for maximizing the effect of the education consciousness and attitude on environment-friendly life resource management in everyday living. The followings are the results of the analysis of the collected data. First, in the aspects of analysis of valiance in the general home environment factors of this research, there were some significance according to fathers and mothers' educational level, fathers' job, the type of a house about students and mothers' life resources use. Second, knowledge about middle school students' life resources use had negative correlations with attitude. But consciousness had positive correlations with attitude. Knowledge about their mothers' life resources use had negative correlations with attitude, but consciousness had positive correlations with attitude. The results of mothers were similar to those of middle school students. Mothers' consciousness and attitude had positive correlations with middle school students' consciousness and attitude.

• Korean Journal of Bronchoesophagology
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• v.7 no.2
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• pp.146-151
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• 2001

Background and Objectives： Primary benign masses in subglottis and trachea are rare. Symptoms of tracheal obstruction are similar to those of bronchial asthma, chronic bronchitis, as well as malignant lesions. Materials and Methods： Eight patients with benign tracheal masses from April 1992 through June 2001, at otolaryngology-head and neck surgery. department of Seoul national university hospital were studied by retrospective medical record review. Results : They were 3 females and 5 males aged from 0 to 57 years. The pathologies of the intratracheal masses were lipoma. tuberculosis, pleomorphic adenoma, hemangioma(two case), reparative giant cell granuloma, epithelial inclusion cyst and nonspecific lymphadenopathy, respectively. The most characteristic symptoms were dyspnea and stridor, both inspiratory and expiratory. Five of them had been treated as bronchial asthma. Conclusion： For the management of patients with the subglottis and tracheal masses, it is important to establish secure airway. regardless of pathology of the masses. The diagnosis should be considered in any patient with asthma-like manifestation, especially who fails to respond to medical treatment. It is necessary to examine the airway thoroughly, and chest and simple cervical X-ray may contribute to the diagnosis of possible intratracheal mass.