• Membrane and Water Treatment
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• v.6 no.5
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• pp.393-409
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• 2015

Zinc and lead pollution are public environmental issues that have attracted lots of attention for a long time. Landfill leachate contains heavy metals, such as Zn(II) and Pb(II), which are usually related to the pollution of groundwater, especially in developing countries. Bentonite has been proven to be effective in enhancing the membrane property of clay, by which landfill liners can have better barrier performance towards the migration of contaminants. In this study, 5% sodium bentonite amended with locally available Fukakusa clay was utilized to evaluate the membrane behavior towards the heavy metals zinc and lead. The chemico-osmotic efficiency coefficient, ${\omega}$, was obtained through Zn(II) and Pb(II) solutions with different concentrations of 0.5, 1, 5, 10, and 50 mM. According to the results, ${\omega}$ continually decreased as the Zn(II) and Pb(II) concentrations increased, which is consistent with the Gouy-Chapman theory. Compared to normal inorganic ions, the membrane behavior towards heavy metal ions was lower. The migration of heavy metal ions was not observed based on experimental results, which can be attributed to the adsorption or ion exchange reaction. The mechanisms of the membrane performance change were discussed with the assistance of XRD patterns, free swelling results, XRF results, and SEM images.

• Women's Health Nursing
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• v.16 no.4
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• pp.390-398
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• 2010

Purpose: The purpose of this study was to analyze periodic screening behaviors for breast cancer and factors affecting the screening behaviors among hospital nurses. Methods: A total of 461 nurses were recruited from 15 hospitals located in two southern areas of Korea. The Champion's Health Beliefs Model Scale-Korean version and a structured study questionnaire were used for data collection. Data were collected during July and August 2008. Results: Nurses who performed periodic mammography accounted for 15.6% of the total, while 22.8% performed periodic breast self-examination (BSE). Among married nurses, the rates of periodic mammography and BSE were significantly different by age, menopausal status, delivery experience, family history of breast cancer, and experiences of cervical cancer screening. Significant factors affecting periodic mammography were family history of breast cancer, experiences of cervical cancer screening, age above 40, and performance of periodic BSE. For health beliefs, levels of severity, confidentiality and barrier were significant factors for periodic BSE. Conclusion: Nurses, who are role models for health promoting behaviors, did not adequately performing periodic BSE and mammography. A health promotion program for breast cancer designed for hospital nurses is needed to improve performance rates for periodic screening behaviors for breast cancer.

• Journal of Power System Engineering
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• v.17 no.5
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• pp.13-22
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• 2013

This paper reports the investigation of the physical and chemical characteristics of the prepared 3Pt-2MgO-$3ZrO_2$-$2CeO_2/Al_2O_3$ DOC, based on its hydrothermal aging. As a result of impregnating and reducing the $H_2PtCl_6$ $6H_2O$ precursor on a ${\gamma}-Al_2O_3$ basis, it was well dispersed into small particles with the range 2-3nm. This was because the $Al_2O_3$ acted as a barrier to prevent movement of the catalyst particles. For a hydrothermally aged catalyst for 9h at $700^{\circ}C$, its performance when purifying harmful gases decreased compared to a fresh catalyst, but its specific surface area was at the same level. This was because the performance of the catalyst was reduced by the sintering of the precious metal Pt, rather than by washcoat sintering and pore clogging. For an excessively hydrothermally aged catalyst for 9h at $850^{\circ}C$, Pt grew into an approximately 50nm class, formed a cluster compared to a fresh catalyst. The $CeO_2$ promoters also formed clusters among components of the same type, reducing their specific surface area to $114m^2/g$, which was 14% less than a fresh catalyst.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.10
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• pp.423-432
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• 2020

Increasing the tourism sector has a positive impact on a country. The Indonesian government has targeted to increase the number of tourists from year to year including the heritage tourism sector. However, the number of the heritage tourism sector increases slowly. To overcome this problem, this research is aimed to investigate the services performed by managements of that sector; the barrier and driver factors of heritage tourism supply chain quality management; and to identify strategies that can be implemented to improve the sector. This study used SERVQUAL method to analyze service performance of the sector. Furthermore, an in-depth interview was conducted to achieve completed objectives. The data obtained from questionnaires and interviews in several heritage tourism areas located in East Java Province of Indonesia. The results show that all SERVQUAL dimensions stay on the adequate value range. Visitors argue that the heritage tourism sector in East Java has interesting locations, collections and circumstances. However, the sector has several weaknesses compared to other tourism sectors. The strategy that can be done to improve the performance of this sector are to perform the area as an event venue, additional visiting hours, integration with other types of tourism sectors, making websites as a means of promotion.

• Proceedings of the KIPE Conference
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• 2018.07a
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• pp.536-538
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• 2018

This paper introduces an enhanced interleaved (IL) PFC (Power Factor Correction) boost converter typed 650V Intelligent Power Module (IPM), which is fully optimized hybrid IGBT converter modules; Silicon (Si) IGBT and Silicon Carbide (SiC) diode, for up to 10kW HVAC (Heating, Ventilation, and Air Conditioning) systems. It utilizes newly developed $4^{th}$ Generation Field Stop (FS) trench IGBTs, $EXTREMEFAST^{TM}$ anti-paralleled diodes, SiC Junction Barrier Schottky (JBS) diodes, Bridge rectifiers, Multi-function LVIC, and Built-in thermistor provide good reliable characteristics for the entire system. This module also takes technical advantage of DBC (Direct Bonded Copper) substrate for the better thermal performance. It is shown that the Si IGBT/SiC diode hybrid IL PFC module can achieve excellent EMI performance and greatly enhance the power handling capability or switching frequency of various applications compared to the Si IGBT/Diode. This paper provides an overall description of the newly developed 650V/50A Hybrid SiC IL PFC IPM product.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.8 no.3
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• pp.29-35
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• 2012

Geothermal heat pump system has been spotlighted as an efficient building energy system, because it has great potentials for reducing energy in building air conditioning and reducing $CO_2$ emissions. However, higher initial cost is a barrier to the promotion of its use. Energy-pile and energy-slab are known as low cost ground heat exchangers comparing with conventional ground heat exchangers, because they utilize building structures as ground heat exchangers. This paper presents the daily cooling performance of a geothermal heat pump system with energy-pile and energy-slab. The energy-piles and the energy-slabs are connected to heat pump units in parallel. The cooling capacity of the system was nearly constant due to the stability of the ground heat exchangers. The stability of the energy-pile was a little higher than that of the energy-stab as a heat sink.

• Membrane and Water Treatment
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• v.10 no.2
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• pp.105-112
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• 2019

On the purpose of conform the more stringent government regulation for turbid stormwater from construction sites, the feasibility and availability of synthetic fiber placing after the conventional protection barrier were tested in this study. Initially, comparative work on the filtering performance of fiber media and conventional gravel filter was carried out, 27% higher filtration capacity was obtained under the similar operational conditions. The filter efficiency was about 20 to 52% with a varying filter depth of 5 to 15cm, presuming at extreme storm flow conditions (800-1500 m/day of filtration rates). Fiber filter was found to have a similar filtration prosperity as grain media; namely, the separation efficiency is directly and inversely proportional to filter depth and rate, respectively. The effects of filter aid (polyaluminium chloride) on filter performance was also investigated, it greatly affected the turbidity reduction at the dosage of 2 mg/L. At the time of breakthrough, a simple filter washing was carried out, herein, the solid recovery achieved over than 88% and greatly determined by operational parameters. Based on the operational data, the empirical models aimed for predicting filtration efficiency were established, which can effectively determine the required filter depth and filtration area in field.

• Korean Journal of Materials Research
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• v.29 no.5
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• pp.317-321
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• 2019

We investigated the characteristics of nano crystalline silicon(nc-Si) thin-film solar cells on graphite substrates. Amorphous silicon(a-Si) thin-film solar cells on graphite plates show low conversion efficiency due to high surface roughness, and many recombination by dangling bonds. In previous studies, we deposited barrier films by plasma enhanced chemical vapor deposition(PECVD) on graphite plate to reduce surface roughness and achieved ~7.8 % cell efficiency. In this study, we fabricated nc-Si thin film solar cell on graphite in order to increase the efficiency of solar cells. We achieved 8.45 % efficiency on graphite plate and applied this to nc-Si on graphite sheet for flexible solar cell applications. The characterization of the cell is performed with external quantum efficiency(EQE) and current density-voltage measurements(J-V). As a result, we obtain ~8.42 % cell efficiency in a flexible solar cell fabricated on a graphite sheet, which performance is similar to that of cells fabricated on graphite plates.

• Journal of Animal Science and Technology
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• v.64 no.4
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• pp.640-653
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• 2022

Deoxynivalenol (DON) is the most common mycotoxin contaminant of cereal-based food and animal feed. The toxicity of DON is very low compared to that of other toxins; however, the most prominent signs of DON exposure include inappetence and body weight loss, which causes considerable economic losses in the livestock industry. This review summarizes critical studies on biological DON mycotoxin mitigation strategies and the respective in vitro and in vivo intestinal effects. Focus areas include growth performance, gut health in terms of intestinal histomorphology, epithelial barrier functions, the intestinal immune system and microflora, and short-chain fatty acid production in the intestines. In addition, DON detoxification and modulation of these parameters, through biological supplements, are discussed. Biological detoxification of DON using microorganisms can attenuate DON toxicity by modulating gut microbiota and improving gut health with or without influencing the growth performance of pigs. However, the use of microorganisms as feed additives to livestock for mycotoxins detoxification needs more research before commercial use.

• Journal of the Semiconductor & Display Technology
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• v.21 no.2
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• pp.7-10
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• 2022

A functional polyethylene terephthalate substrate to increase light extraction efficiency of organic light-emitting diodes is studied. We formed nano-structured PET surfaces by controlling the power, gas, and exposure time of the linear ion-beam. The haze of the polyethylene terephthalate can be controlled from 0.2% to 76.0% by changing the peak-to-valley roughness of nano structure by adjusting the exposure cycle. The treated polyethylene terephthalate shows average haze of 76.0%, average total transmittance of 86.6%. The functional PET increases the current efficiency of organic light-emitting diodes by 47% compared to that of organic light-emitting diode on bare polyethylene terephthalate. In addition to polyethylene terephthalate with light extraction performance, by conducting additional research on the development of functional PET with anti-reflection and barrier performance, it will be possible to develop flexible substrates suitable for organic light-emitting diodes lighting and transparent flexible displays.