• Journal of the Korean Magnetic Resonance Society
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• v.20 no.4
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• pp.121-128
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• 2016

Bean sprouts are often cultivated in the circumstances prevailing in the improper using of germicide and growth enhancer. The influence of ingestion those bean sprouts are unknown. The components of the bean sprouts are needed to evaluate for food safety. The extracts of the control, 0.5 g/L germicide, 1 g/L germicide, 12.5 mL/L growth enhancer and 25 mL/L growth enhancer were used to compare the components in the experiment. Nuclear Magnetic Resonance spectroscopy (NMR) was used to analyze the extracts. Statistical analysis of metabolomics showed significant changes between the control and head and the stem of the bean sprouts. Significant changes in metabolites were identified with the bean sprouts cultivated with germicide and growth enhancer by applying qualitative and quantitative analysis. Similar changes in the area of the bean sprouts were observed after treated to germicide and growth enhancer. Although treating germicide and growth enhancer showed no particular harmful metabolites changes to human, it made significant changes in the morphological and the metabolites of the bean sprouts. These changes indicate that the germicide and growth enhancer has substantially potential to influence the growth of the bean sprouts.

• Preventive Nutrition and Food Science
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• v.20 no.4
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• pp.266-275
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• 2015

Exposure to cadmium (Cd) has harmful effects on the liver and kidney. Resveratrol (RES) is an herbal substance that functions as a protective mediator. This study aimed to investigate the effects of RES on the histology of liver and kidney in Cd-exposed mice. Male mice were divided into 4 groups daily receiving normal saline (1 mL normal saline/d), Cd (1 mg/kg/d), RES (20 mg/kg/d), and Cd plus RES, respectively. After 4 weeks, the liver and kidney components were evaluated using stereological methods. The total volume and number of hepatocytes, and volume of fibrous tissue were respectively increased by 34%, 58%, and a 3-fold in the Cd-exposed mice in comparison to the control animals (P<0.03). On the other hand, the volume of the main vasculature (sinusoids and central veins) was decreased by 36% in the Cd group compared to the control mice (P<0.03). Considering the kidney, the results showed a 3-fold increase in the total glomeruli volume and a 7-fold increase in fibrous tissue in the Cd-treated group compared to the control mice (P<0.03). After Cd treatment, a 32% reduction was observed in the volume and length of the proximal and distal convoluted tubules. RES-treatment alone did not induce any structural changes. In comparison to the Cd group, an increase in the normal components of the liver and kidney and a decrease in the formation of the fibrous and degenerated tissues were observed in the Cd+RES-treated mice (P<0.03).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.3
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• pp.334-339
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• 1997

The feasibility of foam separation to remove solid produced from fish culture water was investigated. Performance characteristics of foam separator were highly dependent upon the operating parameters which were superficial air velocity, Hydraulic retention time (HRT), and foam height. About $50\%$ of the total protein contained in a sample of fish culture water could be removed by foam separator. The removal efficiencies of protein, T-N, TA, and solid components were increased with increasing superficial air velocity and HRT. The combined effects of these operational variables show that removal rates of TVS increase with increasing superficial air velocity and HRT, and decrease as foam height goes up. It could be confirmed that foam separator might offer good perspective for removal of harmful components such as TA and TVS in aquacultural recirculating water.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.4
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• pp.641-647
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• 2017

In order to meet the stricter emission regulations, the proportion of after-treatments for vehicles and vessels has been increasing gradually. The objective of this study is to investigate the physicochemical properties according to ash cleaning agents of CDPF for Diesel Engines. Penetrating agents with strong penetration into ash and a surfactant component to mix water and oil were prepared properly. The cleaning characteristics of S1 sample were good. Washcoat loss rate of S1 sample was lower by about 2.2% because of less KOH component and lower Na2SiO3 content. Washcoat loss rate of S4 sample with an added KOH and Na2SiO3 components by penetration agents was increased by about 13%. In terms of less than about 13% of CDPF's washcoat loss rate, it was able to reduce the harmful gas components.

• Journal of the Korea Convergence Society
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• v.12 no.4
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• pp.161-169
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• 2021

'Clean beauty' attracts attention with an increasing interest in cosmetics without harmful ingredients as people wear masks in the age of COVID-19. Thus, this study selected and analyzed clean beauty cosmetic brands circulated in Korea on/offline in 2020. This study extracted 36 clean beauty brands and selected 20 suitable brands through an experts' analysis. For an analysis of clean beauty cosmetic brand communication, components: naming, logo, color, package, and website were drawn to conduct a survey. Preferred were the words they come up with when they think of nature or health for naming; wordmarks in a simple form for logo; greenish or yellowish for color; the simple form aligned center on the container body for package; and the images of plants, animals, and humans for website. To sum up the components, utilizing natural, clean, and light images harmoniously, acted as a factor for preferring the clean beauty cosmetic brands.

• Transactions of the Korean Society of Automotive Engineers
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• v.15 no.6
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• pp.159-164
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• 2007

The purpose of this study is to reduce harmful emission gases in the range of stable combustion without loss of a thermal efficiency. Therefore, effects of both exhaust gas recirculation(EGR) and synthetic gas addition on engine performance and emission were investigated in a gasoline engine. Synthetic gas(syngas), which is in general prepared from reforming gasoline, was utilized in order to promote stable combustion. The major components of syngas are H2, CO and $N_2$ gases. The percentage of syngas addition was changed from 0 to 30% in energy fraction and EGR rate was varied up to 30%. As a result, $COV_{IMEP}$ as a parameter of combustion stability was decreased and THC/$NO_X$ emissions were reduced with the increase of syngas addition. And $COV_{IMEP}$ was increased with the increase of EGR but $NO_X$ emission was greatly reduced. In addition, under the region where the EGR rate is around 20%, thermal efficiency was improved.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.12 no.10
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• pp.749-757
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• 2002

Excessive vibration in flexible structures is a problem encountered in many different fields, causing fatigue of structural components. Passive techniques, though sometimes limited in their capabilities, have been used in the past to attenuate vibrations. Recently active techniques have been developed to enhance vibration control performance beyond that provided by their passive counterparts. Most often, the focus of active control methods has been to suppress structure displacements. In cases where vibration results in structure failures, displacement suppression may not be the best choice of control approaches (it can, in fact, increase dynamic loads which would be even more harmful to supports) . This paper presents two optimal control methods for attenuating steady state vibrations in flexible structures. One method minimizes shaft displacements while another minimizes dynamic reaction forces. The two methods are applied to a model of a typical flexible structure system and their results are compared. It is found that displacement minimization can increase loads, while load minimization decreases loads.

• Korean Journal of Materials Research
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• v.24 no.4
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• pp.175-179
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• 2014

Ti and Ti alloys have been extensively used in the medical and dental fields because of their good corrosion resistance, high strength to density ratio and especially, their low elastic modulus compared to other metallic materials. Recent trends in biomaterials research have focused on development of metallic alloys with elastic modulus similar to natural bone, however, many candidate materials also contain toxic elements that would be biologically harmful. In this study, new Ti based alloys which do not contain the toxic metallic components were developed using a theoretical method (DV-$X{\alpha}$). In addition, alloys were developed with improved mechanical properties and corrosion resistance. Ternary Ti-Ag-Zr alloys consisting of biocompatible alloying elements were produced to investigate the alloying effect on microstructure, corrosion resistance, mechanical properties and biocompatibility. The effects of various contents of Zr on the mechanical properties and biocompatibility were compared. The alloys exhibited higher strength and corrosion resistance than pure Ti, had antibacterial properties, and were not observed to be cytotoxic. Of the designed alloys' mechanical properties and biocompatibility, the Ti-3Ag-0.5Zr alloy had the best results.

• Journal of ILASS-Korea
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• v.21 no.2
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• pp.71-77
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• 2016

Air pollutants nitrogen oxides are inevitably generated in the combustion reaction. Its amount trend is steadily increasing because the rapid modern industrialization and population growth. For this reason, NOx is controlled to reducing the harmful components in the exhaust gas. So Marine Environment Protection Committee (MEPC) take effect 'Tier I', 'Tier II' of air pollution regulation in 2005 and 2011 respectively. According to NOx emissions are strictly regulated management of the vessel through them. In addition, since 2016 the regulation enter into force in the next step 'Tier III' was confirmed by MEPC 66th committee. It's 80% enhanced emissions limits than the 'Tier I' Alternatively these emission regulation, research is actively being carried out about exhaust gas after-treatment methods through the vessel application of Selective Catalytic Reduction(SCR). Therefore depending on the basic specification of cell density according to the Area velocity, Space velocity, Linear velocity is studied the effects of NOx removal efficiency

• Journal of Advanced Marine Engineering and Technology
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• v.33 no.7
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• pp.1034-1043
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• 2009

Hydrogen energy is becoming popular day by day due to its renewability and pollutaaant free natures. Hydrogen gas pressure which is after passing through reciprocating compressor part has high pulsation wave form. A unit, snubber is used as compressor components to reduce the harmful pulsation waveform and to remove the impurities in the hydrogen gas. An experiment has been conducted to investigate the pulsation reduction performance of different arrangement of snubber i.e. snubber array used in reciprocating compression system. Analyzing the snubber array experimental data, it is found that the pressure fluctuations are reduced from 90.1977% ~ 92.6336% with pressure loss 1.5013% ~ 4.9034% for compressor operation at different speed which ensure the good performance of snubber-array as pulsation damper in hydrogen compressing system.