• Clean Technology
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• v.12 no.3
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• pp.113-127
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• 2006

Waste lubricating oil(WLO)s have been recycled as energy source through direct fuel in cement kilns and fossil power plants, or as fuel oils, or re-refined lubricating base oils. In our country, they have been recycled as low grade fuel oil through chemical treatment process. In 2003, extended producer responsibility (EPR) system was adopted from deposit system on sale of lubricating oils in order to promote their recycleing rate. However, our recycling rate of WLOs have been stagnant(below 70%) for last 5 years. And there has been no research work on recycling of WLOs as re-refined base oil until now in this country. Stabilization technology of thermally cracked oils to reduce tar and malodor and to improve their color for production of high grade fuel oil, and a novel process production of high grade re-refined lubricating base oil from WLOs have been developed and commercialized recently in Canada and U.S.A., respectively. Several countries like Australia, Italy, Germany and U.S.A., etc. are encouraging recycling companies to recycle WLOs as re-refined lubricating oil by giving greater subsidies or benefits compared to other recycling methods. They also adopt a policy to purchase re-refined lubricating oil preferentially in the federal or local governments and to recommend consumers to purchase it willingly. Based on the facts that several advanced countries have adopted a policy to recycle WLOs as re-refined base oil for saving of petroleum resource and reduction of environmental pollution, it is right time to be considered that our present policy for recycling of WLOs should be reevaluated and the new policy of their environmental-friendly and sustainable recycling should be established.

• Journal of Ginseng Research
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• v.40 no.2
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• pp.127-134
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• 2016

Background: Rhizospheric fungi play an essential role in the plantesoil ecosystem, affecting plant growth and health. In this study, we evaluated the fungal diversity in the rhizosphere soil of 2-yr-old healthy Panax notoginseng cultivated in Wenshan, China. Methods: Culture-independent Illumina MiSeq and culture-dependent techniques, combining molecular and morphological characteristics, were used to analyze the rhizospheric fungal diversity. A diffusion test was used to challenge the phytopathogens of P. notoginseng. Results: A total of 16,130 paired-end reads of the nuclear ribosomal internal transcribed spacer 2 were generated and clustered into 860 operational taxonomic units at 97% sequence similarity. All the operational taxonomic units were assigned to five phyla and 79 genera. Zygomycota (46.2%) and Ascomycota (37.8%) were the dominant taxa; Mortierella and unclassified Mortierellales accounted for a large proportion (44.9%) at genus level. The relative abundance of Fusarium and Phoma sequenceswas high, accounting for 12.9% and 5.5%, respectively. In total,113 fungal isolates were isolated from rhizosphere soil. They were assigned to five classes, eight orders (except for an Incertae sedis), 26 genera, and 43 species based on morphological characteristics and phylogenetic analysis of the internal transcribed spacer. Fusarium was the most isolated genus with six species (24 isolates, 21.2%). The abundance of Phoma was also relatively high (8.0%). Thirteen isolates displayed antimicrobial activity against at least one test fungus. Conclusion: Our results suggest that diverse fungi including potential pathogenic ones exist in the rhizosphere soil of 2-yr-old P. notoginseng and that antagonistic isolates may be useful for biological control of pathogens.

• International Journal of Highway Engineering
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• v.3 no.4 s.10
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• pp.127-136
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• 2001

To increase the structural integrity of concrete box culvert good compaction by the dynamic compaction roller with bi9 capacity is as effective as good backfill materials. It is needed for effective compaction that a compaction roller closes to concrete structure with high frequency. However structural distress of the culvert could be occur due to the excessive earth pressure by great dynamic compaction load. To investigate the characteristics of Induced stress by compaction, a box culvert was constructed with changing cushion materials and compaction methods. Two types of cushion material such as tire rubber chip and EPS(Expanded Polystyrene) were used as cushion panels and they are set on the culverts before backfill construction. Laboratory test result of cushion material says that the value of dynamic elastic modulus of rubber is lesser than that of EPS. On the other hand, material damping of rubber material is greater than that of EPS. In most case, dynamic compaction rollers with 10.5 ton weights were used and vibration frequency was applied 30Hz for the great compaction energy. This paper presents the main results on the characteristics of dynamic earth pressures during compaction. The amounts of induced dynamic pressures$(\Delta\sigma\;h)$ by compaction are affected with construction condition such as compaction frequency, depth of pressure cell, distance between roller and the wall of culvert and roller direction. Based on the measured values dynamic lateral pressure on the culverts, it could be said that orthogonal direction of roller to the length of culvert is more effective to compaction efficiency than parallel direction.

• Korean Journal of Community Nutrition
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• v.7 no.6
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• pp.833-843
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• 2002

This study was carried out to investigate the effect of hygiene education on the microbiological changes of processing utensils and the environmental in the manufacture of cereals and to evaluate the Cd, Pb contents and nutrient compositions of 11 cereals. The result of microbiological evaluation was that fungi, coliforms and staphylococcus species were detected in employees, on equipment, utensils and environments in the first inspection. Fungi were detected in most of the cereals, staphylococcus species were detected in soybeans, perilla seeds and sea tangle How, and bacillus cereus was detected in sorghum and black sesame seeds. The water content of rice, barley, glutinous rice, brown rice and carrot flour in packaged products, and in carrot flour, angelica keiskei, carrot, sea mustard and potato in bulk products was in excess of 8.0%. The Pb content of cereals was 0.14-0.51 mg/kg and Cd was not found. The acid value of Job s tears flour and black sesame seed flour was higher than 5.0 mg/g oil. Cereals were manufactured from 41 different cereals and grains, legumes, seeds and nuts, vegetables, potatoes, seaweeds, fruits, glucose and salt. The average content of cereals and grains, legumes, and seeds and nuts in cereals was 75.75%, 16.19% and 4.93%, respectively. The mean nutrient content per 100 g of cereals was calories 365.8kcal, protein 13.3 g, fats 5.9 g, carbohydrates 63.4 g, Ca 91.8 mg, p 269.9 mg, Fe 3.15 mg, Na 76.2 g, K 421.8 mg, Zn 2.33 mg, Vit. A 12.5 R.E., Vit. B$_1$0.23 mg, Vit. $B_2$ 0.16 mg, Vit. $B_6$ 0.46 mg, Niacin 3.5 mg, Vit. C 1.36 mg, folic acid 62.3 $\mu$g and Vit. E 1.24 mg. When nutrients value of 48 g of cereals and 200 $m\ell$l of milk was compared to 1/3 of the RDA, the values were below than 60% of 1/3 of the RDA except Na, K, Vitamin $B_1$ and C contents. The average carbohydrate : protein : fat ratio of energy intake was 54.27 : 17.45 : 28.28, respectively. Therefore, a training program consisting of the education of the staff in surveillance and standard operating procedures, the elimination of dangerous procedures, sanitation checklist, the implementation of Preparation methods and standard recipes for cereals is required.

• Journal of Advanced Marine Engineering and Technology
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• v.39 no.7
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• pp.773-778
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• 2015

Global warming has recently become an issue that has resulted in a growing trend to minimize environmental pollution. The International Maritime Organization (IMO) has shown that the majority of marine atmospheric pollution occurs as a result of emissions from marine vessels. Therefore, the environmental regulations and emission standards regarding marine vessels have gradually become stricter, and the research and development in this area is experiencing significant progress. In this study, a nozzle for a fuel oil scrubber was investigated using computational fluid dynamics (CFD) and particle imaging velocimetry (PIV). Experiments were conducted on scaled-down model of the scrubber to determine its performance, which was then compared with CFD results. Based on the experimental results, it was found that at a spray angle of $66^{\circ}$, the spray velocity at the nozzle was 20.1 m/s. From this comparison, a full-scale scrubber model was analyzed using CFD, and the effect of the positioning of the nozzle was studied.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.10
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• pp.1660-1669
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• 2018

Objective: This study was conducted to evaluate the effect of probiotics (Bacillus subtilis and Enterococcus faecium) and xylo-oligosaccharide (XOS) supplementation on growth performance, nutrient digestibility, serum profiles, intestinal health, fecal microbiota and noxious gas emission in weanling pigs. Methods: A total of 240 weanling pigs ([Yorkshire${\times}$Landrace]${\times}$Duroc) with an average body weight (BW) of $6.3{\pm}0.15kg$ were used in this 28-day trial. Pigs were randomly allocated in 1 of the following 4 dietary treatments in a $2{\times}2$ factorial arrangement with 2 levels of probiotics (0 and 500 mg/kg probiotics) and XOS (0 and 200 mg/kg XOS) based on the BW and sex. Results: Administration of probiotics or XOS improved average daily gain (p<0.05) during 0 to 14 d and the overall period, while pigs that were treated with XOS had a greater average daily gain and feed efficiency (p<0.05) compared with unsupplemented treatments throughout 15 to 28 d and the whole experiment. Either probiotics or XOS treatments increased the apparent total tract digestibility of nutrients (p<0.05) during 0 to 14 d. No effects on serum profiles were observed among treatments. The XOS increased villus height: crypt depth ratio in jejunum (p<0.05). The supplementation of probiotics (500 mg/kg) or XOS (200 mg/kg) alone improved the apparent total tract digestibility of dry matter, nitrogen and gross energy on d 14, the activity of trypsin and decreased fecal NH3 concentration (p<0.05). Administration of XOS decreased fecal Escherichia coli counts (p<0.05), while increased lactobacilli (p<0.05) on d 14. There was no interaction between dietary supplementation of probiotics and XOS. Conclusion: Inclusion of XOS at 200 mg/kg or probiotics (Bacillus subtilis and Enterococcus faecium) at 500 mg/kg in diets containing no antibiotics significantly improved the growth performance of weanling pigs. Once XOS is supplemented, further providing of probiotics is not needed since it exerts little additional effects.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.37
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• pp.34.1-34.14
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• 2015

Background: Over the past 30-40 years, various carbon implant materials have become more interesting, because they are well accepted by the biological environment. The traditional carbon-based polymers give rise to many complications. The polymer complication may be eliminated through carbon fibres bound by pyrocarbon (carbon/carbon). The aim of this study is to present the long-term clinical results of carbon/carbon implants, and the results of the scanning electron microscope and energy dispersive spectrometer investigation of an implant retrieved from the human body after 8 years. Methods: Mandibular reconstruction (8-10 years ago) was performed with pure (99.99 %) carbon implants in 16 patients (10 malignant tumours, 4 large cystic lesions and 2 augmentative processes). The long-term effect of the human body on the carbon/carbon implant was investigated by comparing the structure, the surface morphology and the composition of an implant retrieved after 8 years to a sterilized, but not implanted one. Results: Of the 16 patients, the implants had to be removed earlier in 5 patients because of the defect that arose on the oral mucosa above the carbon plates. During the long-term follow-up, plate fracture, loosening of the screws, infection or inflammations around the carbon/carbon implants were not observed. The thickness of the carbon fibres constituting the implants did not change during the 8-year period, the surface of the implant retrieved was covered with a thin surface layer not present on the unimplanted implant. The composition of this layer is identical to the composition of the underlying carbon fibres. Residual soft tissue penetrating the bulk material between the carbon fibre bunches was found on the retrieved implant indicating the importance of the surface morphology in tissue growth and adhering implants. Conclusions: The surface morphology and the structure were not changed after 8 years. The two main components of the implant retrieved from the human body are still carbon and oxygen, but the amount of oxygen is 3-4 times higher than on the surface of the reference implant, which can be attributed to the oxidative effect of the human body, consequently in the integration and biocompatibility of the implant. The clinical conclusion is that if the soft part cover is appropriate, the carbon implants are cosmetically and functionally more suitable than titanium plates.

• Journal of Conservation Science
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• v.30 no.1
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• pp.95-101
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• 2014

Silver objects tarnish with black from reaction with sulfurous acid or hydrogen sulfide of atmospheric. Blackening of silver objects results from formation of silver sulfide($Ag_2O$) on the surface. Silver sulfide usually is usually removed by conservation treatment. There are several cleaning methods such as chemical, electrochemical and micro-abrasion cleaning, but all of them consume silver. This study investigated the safe and effective parameter of laser cleaning by test on silver coupons. Laser cleaning is a selective process for the removal of specific substances. At first, laser cleaning applied to plain silver coupons, which were not corroded, to find out the safe range of laser energy density. From results, plain silver coupons were not changed at 1064nm below $4.00J/cm^2$ and at 532nm below $2.39J/cm^2$. The corrosion layer(silver sulfide) of artifical corroded silver coupons was removed at 1064nm with $2.39J/cm^2$ by 5~10 pulses and at 532nm with $1.19J/cm^2$ by 5~10 pulses. The removal thickness of corrosion layer was about 13-25nm per a laser pulse using AES analysis. In addition, laser cleaning tested the tarnish silver rings based on the results of silver coupons. As a result of test, the black surface were clean successfully and gave luster of silver, which showed the application possibility of laser cleaning for silver objects.

• Journal of Biosystems Engineering
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• v.39 no.3
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• pp.227-234
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• 2014

Purpose: The aim of this research was to develop and evaluate natural hydroxyapatite (HA) ceramics produced from the heat treatment of pig bones. Methods: The properties of natural HA ceramics produced from pig bones were assessed in two parts. Firstly, the raw materials were characterized. A temperature of $1,200^{\circ}C$ was chosen as the calcination temperature. Fine bone powders (BPs) were produced via calcinations and a milling process. Sintered BPs were then characterized using field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), X-ray fluorescence spectroscopy (XRF), energy dispersive X-ray spectroscopy (EDX), Fourier transform infrared (FTIR) spectroscopy, and a 2-year in vitro degradability test. Secondly, an indirect cytotoxicity test was conducted on human osteoblast-like cells, MG63, treated with the BPs. Results: The average particle size of the BPs was $20{\pm}5{\mu}m$. FE-SEM showed a non-uniform distribution of the particle size. The phase obtained from XRD analysis confirmed the structure of HA. Elemental analysis using XRF detected phosphorus (P) and calcium (Ca) with the Ca/P ratio of 1.6. Functional groups examined by FTIR detected phosphate ($PO{_4}^{3-}$), hydroxyl ($OH^-$), and carbonate ($CO{_3}^{2-}$). The EDX, XRF, and FTIR analysis of BPs indicated the absence of organic compounds, which were completely removed after annealing at $1,200^{\circ}C$. The BPs were mostly stable in a simulated body fluid (SBF) solution for 2 years. An indirect cytotoxicity test on natural HA ceramics showed no threat to the cells. Conclusions: In conclusion, the sintering temperature of $1,200^{\circ}C$ affected the microstructure, phase, and biological characteristics of natural HA ceramics consisting of calcium phosphate. The Ca-P-based natural ceramics are bioactive materials with good biocompatibility; our results indicate that the prepared HA ceramics have great potential for agricultural and biological applications.

• Information Systems Review
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• v.18 no.2
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• pp.127-149
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• 2016

Based on a comprehensive literature review on Theory of Planned Behavior and Social Cognitive Theory, this study proposes and empirically examines a structural model consisting of factors affecting voluntary information security compliance behavior. To test the proposed research model, the study analyzes survey results from employees of a major Korean energy company, which employs an enterprise compliance support system. Results indicate three factors: compliance behavioral belief and compliance knowledge affect compliance behavior; compliance knowledge works as a mediator in the relationship between compliance behavioral belief and compliance behavior; and the more relevant the compliance is to an employee's job, the more the employee prioritizes compliance knowledge. This study suggests methods for encouraging employees to embrace voluntary, positive information security compliance standards. By doing so, this article aims to promote a more effective corporate compliance system for information security and enhance sustainable management practices.