• Korean Journal of Environmental Biology
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• v.34 no.3
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• pp.177-182
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• 2016

Malodor emitted while producing fertilizer from hatchery egg waste treated with microorganism is an important limiting factor. To reduce this problem, we attempted to use two yeast strains, Saccharomyces cerevisiae, KACC 30008 and KACC 30068. Both yeast strains reduce ammonia gas emission 35.4% than only treated with bacterium, Bacillus amyloliquefaciens. When both strains were used together, that was reduced as 57.1%. KACC 30008 and 30068 strains reduced hydrogen sulfide 42 and 90.4%, respectively. Both strains together reduced hydrogen sulfide gas as 98.5%. KACC 30008 did not decrease methyl mercaptan emission. However KACC 30068 decreased 40% and both strains together decreased the gas emission as 66.7%. Overall, this study showed that yeast treatment could enhance the effect of B. amyloliquefaciens treatment in the reduction of malodorous gas emission.

• Journal of agriculture & life science
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• v.46 no.4
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• pp.119-127
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• 2012

To investigate the influence of multi-probiotic, fermented ginseng byproduct and fermented sulfone on the performance, intestinal microflora and immunity of broiler, a five weeks trial was conducted with 340, 1-d-old $Ross{\times}Ross$ broiler. All broilers were divided into five different groups having 68 birds in each treatment, and they were assigned as control, antibiotic avilamycin (AB), multi-probiotic (MP), fermented sulfone (FS) and fermented ginseng byproduct (FGB). Each artificial or naturally derived probiotic was inoculated 0.1% level with the basal diet, and all diets were provided to birds for five weeks. Weight gain and feed intake were measured weekly basis, and blood, spleen and feces were collectedand used for the physiological properties of broiler chickens. All performances and cholesterol profiles were not significantly differed but numerically lower level of neutral fat and LDL was found in multi-probiotics and FGB treatments respectively. The salmonella spp and E. coli numbers in the ileum were high in control in relation to those of other treatments and were significantly decreased in antibiotics treatments (p<0.05). In addition, Lactobacillus spp. showed significantly higher proliferation in MP as compared to that of others (p<0.05). Fecal ammonia and $CO_2$ gas emission was significantly decreased in MP, FGB and FS, respectively (p<0.05), but significantly increased proliferation of spleen was determined in MP group in comparison of other treatments (p<0.05). Therefore, the results indicates that multi-probiotics would be valuable feed additives to improve the salmonella, E. coli and Lactobacillus proliferation, and manure gas emission of broiler chickens, but further study related to the production of manure gas emission of MP is necessary.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.3
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• pp.483-490
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• 2019

Assessing the effect of forest fires and measuring the gas concentration around a fire has received little attention. Therefore, the concentrations of various gases in areas surrounding a fire need to be measured by the development of a suitable device. Unlike conventional portable devices, the AQS (Air Quality System) proposed in this paper is a portable instrument that measures five types of gases simultaneously, including CO, CO2, NOx, VOCs, and NH3, and has high durability through sensor protection algorithms. A PC-based program with an AQS connection was developed to monitor the real-time changes in the gas concentration. The reliability of the developed device was proven through a comparison of the results with other commercial gas analyzers. Measurements of the concentration due to indoor and outdoor fires were performed around a fire area to review the applicability and the predicted results were obtained.

• Journal of Environmental Science International
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• v.11 no.6
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• pp.577-582
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• 2002

Selective catalytic reduction and selective non-catalytic reduction processes are mainly used to treat nitrogen oxidants generated from fossil-fuel combustion. Especially, the selective non-catalytic reduction process can be operated more economical and designed more simply than the selective catalytic reduction. For this reason, many researchers carried out to increase the removal efficiency of nitrogen oxidants in the condition of low oxygen concentration by using the selective non-catalytic reduction process. However, this study was flue gas contained high oxygen concentration of 20(v/v%) with ammonia as a reducing agent. Moreover, it carried out experiment with many factors that are reaction temperature, retention time, initial NO concentration, NSR(normalized stoichiometric ratio). It was determined optimal operating conditions to improve NO removal efficiency with SNCR process. The De-NOx efficiency was increased with NSR, initial NO concentration and retention time increasement. This study has NO removal efficiency over 80% in the high oxygen concentration as well as low oxygen concentration. The injection of reducing agent may be considered for SNCR process and facility operation in 850$\^{C}$ of optimal condition.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.26 no.6
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• pp.446-450
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• 2013

Growth mechanism of GS-MBE(Gas source-Molecular Beam Epitaxy) has been investigated. We observed that the growth rate of GaN films is changing from 520 nm/h to 440 nm/h by the variation of V/III ratio under nitrogen-rich growth condition. It was explained that the amount of hydrogen on the growth front varies by the ammonia flow, and gallium hydrides are generated on the surface by a reaction of hydrogen and gallium, resultantly the amount of gallium supplying is changing along with the $NH_3$ flow. Reflection high energy electron diffraction (RHEED) observation was used to confirm the N-rich condition. The crystal quality of GaN was estimated by photoluminescence (PL) and X-ray diffraction (XRD).

• 연구논문집
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• s.23
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• pp.93-107
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• 1993

The chemistry and performance characteristics of the EBDS process have been introduced, in which experimental results from laboratory, test plant, and pilot plant studies agree very well and can be understood from detailed kinetic models. The parametric dependencies of the NOx and $SO_2$, removal yields on the input conditions have been discussed and formulated quantitatively. The process is best suited for flue gas with high $SO_2$, loadings. The operation conditions, such as dose, ammonia, and water additions, can be adjusted fast upon load changes. The process works waste water free and the major product is a mixture of ammonium nitrate and sulfate that can be used as fertilizer. The up-date results show that the EBDS technology is safe and competitive with other already well-established technologies. Due to these interesting features, the electron beam process has gained much international recognition. Demonstration units of 100MW have been proposed in the United States and Japan. Further pilot plants are under construction in Poland and China, countries that make abundant use of highsulfur coal. Additional research activities are under way to further improve the energy efficiency of process, and accelerator prices have been decreasing during the past 10 years. So the EBDS process has a good chance to start a new generation of emission-control technology.

• Special Issue of the Society of Naval Architects of Korea
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• 2017.10a
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• pp.93-104
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• 2017

IMO type C independent tank is one of the cargo containment system specified on IGC code. It is normally adopted for small and medium size liquefied gas carrier's cargo containment system and it can be applied to fuel tank of LNG fueled vessel. This study focuses on rule scantling process and evaluation methods in early design stage of type C independent tank. Actual design results of 22K LPG/Ammonia/VCM carrier's No.2 cargo tank are demonstrated. This paper presents the calculation methods of design acceleration and liquid height for internal design pressure as defined on IGC code. And this paper shows the applied results of classification rules about shell thickness requirement and buckling strength. Additionally this paper deals with evaluation methods of structural strength and cumulative fatigue damage using FE analysis.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.6
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• pp.797-805
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• 2014

The effect of concentrate mixtures with crude protein (CP) levels 10%, 13%, 16%, and 19% and diets with roughage to concentrate ratios 80:20, 60:40, 40:60, and 20:80 (w/w) were determined on dry matter (DM) and organic matter (OM) digestibility, and fermentation metabolites using an in vitro fermentation technique. In vitro fermented attributes were measured after 4, 24, and 48 h of incubation respectively. The digestibility of DM and OM, and total volatile fatty acid (VFA) increased whereas pH decreased with the increased amount of concentrate in the diet (p<0.001), however CP levels of concentrate did not have any influence on these attributes. Gas production reduced with increased CP levels, while it increased with increasing concentrate levels. Ammonia nitrogen ($NH_3$-N) concentration and microbial CP production increased significantly (p<0.05) by increasing CP levels and with increasing concentrate levels in diet as well, however, no significant difference was found between 16% and 19% CP levels. Therefore, 16% CP in concentrate and increasing proportion of concentrate up to 80% in diet all had improved digestibility of DM and organic matter, and higher microbial protein production, with improved fermentation characteristics.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.293-293
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• 2010

Carbon nanotubes (CNTs) have attracted considerable attention as possible routes to device miniaturization due to their excellent mechanical, thermal, and electronic properties. These properties show great potential for devices such as field emission displays, CNT based transistors, and bio-sensors. The metals such as nickel, cobalt, gold, iron, platinum, and palladium are used as the catalysts for the CNT growth. In this study, diamond-like carbon (DLC) was used for CNT growth as a nonmetallic catalyst layer. DLC films were deposited by a radio frequency (RF) plasma-enhanced chemical vapor deposition (RF-PECVD) method with a mixture of methane and hydrogen gases. CNTs were synthesized by a hot filament plasma-enhanced chemical vapor deposition (HF-PECVD) method with ammonia (NH3) as a pretreatment gas and acetylene (C2H2) as a carbon source gas. The grown CNTs and the pretreated DLC filmswere observed using field emission scanning electron microscopy (FE-SEM) measurement, and the structure of the grown CNTs was analyzed by high resolution transmission scanning electron microscopy (HR-TEM). Also, using energy dispersive spectroscopy (EDS) measurement, we confirmed that only the carbon component remained on the substrate.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.662-665
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• 2002

The growth of carbon nanotubes (CNTs) was carried out using ratio frequency plasma enhanced chemical vapor deposition (rf PECVD) system equipped with dc bias for the directional growth. Acetylene and ammonia gas were used as the carbon source and a catalyst. The relation between gas flow rate and dc bias on the growth of CNTs was investigated. We studied the relation between emission properties and the directionality of CNTs grown under different dc bias voltage.