• Elastomers and Composites
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• v.34 no.2
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• pp.156-176
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• 1999

Rubber chemicals such as accelerators, antidegradants, vulcanizing agents, processing agents and retarders are very important to the production and protection of tires and rubber goods. The use of accelerators and antidegradants are evaluated in various tire components. This paper will focus on how to vulcanize tires economically and maintain the physical properties of each tire component without severe degradation due to oxygen, heat and ozone. Also, new non-nitrosoamine accelerators and non-staining antiozonants will be discussed. Lastly, the future requirements of antidegradants and accelerators in the tire industry will be reviewed. Tires have been vulcanized with Sulfenamides as primary accelerators and either Guamdine's or Thiurams as secondary accelerators to achieve proper properties at service conditions. However, interior components such as the carcass can be vulcanized with Thiazoles as a primary accelerator to cure faster than the external components. Using the combination of Sulfenamide with secondary accelerators in a tire tread compound and the combination of a Thiazole and Guanidine in a carcass compound will be presented with performance data. Uniroyal Chemical and another Rubber Chemical Manufacturer have developed, "Tetrabenzyl Thiuram Disulfide," (TBzTD) as a non-Nitrosoamine accelerator, which could replace Nitrosoamine generating Thiurams. This new accelerator has been evaluated in a tread compound as a secondary accelerator. Also, Flexsys has developed N-t-butyl-2-benzothiazole Sulfenamide (TBSI) as a non-Nitrosoamine accelerator which could replace 2-(Morpholinothio) -benzothiazole (MBS), a scorch delayed Sulfendamide accelerator. TBSI has been evaluated in a Natural Rubber (NR) belt skim compound vs. MBS. An optimum low rolling resistant cure system has been developed in a NR tread with Dithiomorpholine (DTDM). Also, future requirements for developing accelerators will be discussed such as the replacement of DTDM and other stable crosslink systems. Antidegradants are divided into two different types for use in tire compounds. Internal tire compounds such as apex, carcass, liner, wire breaker, cushion, base tread and bead compounds are protected by antioxidants against degradation from oxygen and heat due to mechanical shear. The external components such as sidewall, chafer and cap tread com-pounds are protected from ozone by antiozonants and waxes. Various kinds of staining and non-staining antioxidants have been evaluated in a tire carcass compound. Also, various para-phenylene diamine antiozonants have been evaluated in a tire sidewall compound to achieve the improved lifetime of the tire. New non-staining antiozonants such as 2, 4, 6-tris-(N-1, 4-dimethylpentyl-p-phenylene diamine) 1, 3, 5 Trizine (D-37) and un-saturated Acetal (AFS) will be discussed in the tire sidewall to achieve better appearance. The future requirements of antidegradants will be presented to improve tire performance such as durability, better appearance and longer lasting tires.

• Korean Journal of Community Nutrition
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• v.20 no.1
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• pp.61-72
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• 2015

Objectives: This study was performed to examine nutrition problems and causes/contributing risk factors. Methods: This study was conducted using data 1,863 adults visited Asan health screening & promotion center located in Seoul, Korea during May to June of 2013. We used Nutrition Care Process Model developed by the International Dietetics & Nutrition Terminology (IDNT). Results: The most frequent nutrition problem in male subjects was excessive alcohol intake. Men in fifties showed the highest rate of excessive alcohol intake among the age groups examined (22.4%). By comparison, the most frequent nutrition problem in women was inadequate protein intake. Women in fifties exhibited the highest rate of inadequate protein intake (22.5%). The most common contributing factors for these observations were a low preference for dairy products followed by high preference for alcohol and a deficit in food-and nutrition-related knowledge, regardless of the sex and age. The most common nutrition problem observed among the group diagnosed with hyperglycemia or hypertriglyceridemia or hyperuricemia or fatty liver was excessive alcohol intake (p < 0.001), whereas the group diagnosed with hyperglycemia or hypercholesterolemia showed significantly higher rate of inappropriate intake of carbohydrate (fructose) compared to the group not diagnosed with such disease conditions (p < 0.05). The group diagnosed with hypercholesterolemia, hyperuricemia and fatty liver showed significantly higher occurrence of inappropriate intake of fat (saturated fat) than the group free of such diseases (p < 0.001). The osteopenia group showed higher rate of inadequate protein intake (p < 0.001) and the fatty liver group with excessive energy intake (p < 0.001). Overall, the results suggest that there is a significant relationship between nutrition problems and health conditions found in groups diagnosed with a diverse array of medical conditions. Conclusions: Therefore, we strongly suggest that dieticians should implement nutrition interventions with people visiting health screening & promotion center based on nutrition problems and the contributing factors diagnosed by dietitions in order to prevent chronic diseases in this population.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.34-34
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• 2012

Heavy storms rainfall has caused many landslides and slope failures especially in the mountainous area of the world. Landslides and slope failures are common geologic hazards and posed serious threats and globally cause billions in monetary losses and thousands of casualies each year so that studies on slope stability and its failure mechanism under rainfall are being increasing attention of these days. Rainfall-induced slope failures are generally caused by the rise in ground water level, and increase in pore water pressures and seepage forces during periods of intense rainfall. The effective stress in the soil will be decreased due to the increased pore pressure, which thus reduces the soil shear strength, eventually resulting in slope failure. During the rainfall, a wetting front goes downward into the slope, resulting in a gradual increase of the water content and a decrease of the negative pore-water pressure. This negative pore-water pressure is referred to as matric suction when referenced to the pore air pressure that contributes to the stability of unsaturated soil slopes. Therefore, the importance is the study of saturated unsaturated soil behaviors in evaluation of slope stability under heavy rainfall condition. In an actual field, a series of failures may occur in a slope due to a rainfall event. So, this study attempts to develop a numerical model to investigate this failure mechanism. A two-dimensional seepage flow model coupled with a one-dimensional surface flow and erosion/deposition model is used for seepage analysis. It is necessary to identify either there is surface runoff produced or not in a soil slope during a rainfall event, while analyzing the seepage and stability of such slopes. Runoff produced by rainfall may result erosion/deposition process on the surface of the slope. The depth of runoff has vital role in the seepage process within the soil domain so that surface flow and erosion/deposition model computes the surface water head of the runoff produced by the rainfall, and erosion/deposition on the surface of the model slope. Pore water pressure and moisture content data obtained by the seepage flow model are then used to analyze the stability of the slope. Spencer method of slope stability analysis is incorporated into dynamic programming to locate the critical slip surface of a general slope.

• Korean Journal of Soil Science and Fertilizer
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• v.41 no.2
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• pp.118-125
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• 2008

Diverse organic amendments available in local areas have been used to improve soil quality in red pepper field and so the need for investigating the soil chemical and biological properties changed by the organic amendments application is increasing. Soil microbial diversities were measured by phospholipid fatty acid (PLFA) and Biolog $EcoPlate^{TM}$. Compost was most effective for improving soil chemical properties including pH, EC, total nitrogen, P, K, and Ca, and bark increased soil organic matter significantly (P=0.05). Compost increased the fatty acids indicating actinomycetes and vascular arbuscular fungi, and ratio of cy19:0/18:1w7c and monounsaturated fatty acids/saturated fatty acids in soils in PLFA analysis. Bark increased soil fungal indicators in PLFA analysis (P=0.05). Principal component analysis of Biolog EcoPlate data and PLFA differentiated the compost- and bark-amended soils from other organic matteramended soils especially the soil incorporated with compost. More researches are needed to use bark for improving soil microbial properties because the soil chemical and microbiological properties caused by compost and bark are significantly different.

• Journal of Korean Society of Transportation
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• v.30 no.6
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• pp.71-80
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• 2012

This research suggested a real-time traffic signal control algorithm using individual vehicle travel times on an isolated signal intersection. To collect IDs and passing times from individual vehicles, space-based surveillance systems such as DSRC were adopted. This research developed models to estimate arrival flow rates, delays, and the change rate in delay, by using individual vehicle's travel time data. This real-time signal control algorithm could determine optimal traffic signal timings that minimize intersection delay, based on a linear programming. A micro simulation analysis using CORSIM and RUN TIME EXTENSION verified saturated intersection conditions, and determined the optimal traffic signal timings that minimize intersection delay. In addition, the performance of algorithm varying according to market penetration was examined. In spite of limited results from a specific scenario, this algorithm turned out to be effective as long as the probe rate exceeds 40 percent. Recently, space-based traffic surveillance systems are being installed by various projects, such as Hi-pass, Advanced Transportation Management System (ATMS) and Urban Transportation Information System (UTIS) in Korea. This research has an important significance in that the propose algorithm is a new methodology that accepts the space-based traffic surveillance system in real-time signal operations.

• Journal of The Korean Society of Grassland and Forage Science
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• v.36 no.1
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• pp.29-33
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• 2016

In order to provide basic data to predict changes of milk components in milk yield, this study was conducted to compare nutritive values of diets collected from organic dairy farms (ODF) and conventional dairy farms (CDF) of Chungnam and Jeonbuk in Korea. The contents of crude fat, crude fiver, neutral detergent fiber, and acid detergent fiber in diets of ODF were significantly (p<0.05) higher compared to those of CDF. The contents of crude protein and crude ash in ODF were also higher (p<0.05) than those of CDF. The contents of calcium, ferrum, and phosphorus in diets of ODF were similar to those of CDF. The contents of potassium, magnesium, and iodine in diets of ODF were higher (p<0.05) than those of CDF. The contents of total saturated and unsaturated fatty acids in diets of ODF were higher (p<0.05) compared to those of CDF. The contents of oleic acid, linoleic acid, and linolenic acid in diets of ODF were higher (p<0.05) compared to those of CDF. However, the contents of myristic acid, palmitic acid, and stearic acid in diets of ODF were lower (p<0.05) compared to those of CDF.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.7
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• pp.891-896
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• 2006

The chemical components and antimicrobial effects were investigated to provide basic data that will predict the usefulness of Corni fructus as food materials. The carbohydrate, crude protein, lipid and ash contents of Corni fructus were 87.7, 3.2, 4.5 and 4.6% in dry basis, respectively. Total amino acid content of Corni fructus was 2,470 mg%. Major amino acids of Corni fructus were aspartic acid (523 mg%) and glutamic acid (247 mg%). The compositions of total saturated and unsaturated fatty acids of Corni fructus were 30.8% and 69.2%, respectively. Major fatty acids of Corni fructus were linolic acid (33.3%), palmitic acid (25.1%), linolenic acid (21.6%) and olcic acid (13.2%). The mineral contents of Corni fructus were 2067.5 mg% of K, 372.9 mg% of Ca and 98.4 mg% of Mg in dry basis. The organic acid contents of Corni fructus were 19,478 mg% of formic acid, 18,167 mg% of succinic acid, 14,487 mg% of malonic acid and 13,018 mg% of malic acid. Naengmyon yuksu (beef stock for cold noodles) were prepared with the addition of Corni fructus. Corni fructus added to Naengmyon yuksu inactivated microorganism and inhibited the growth of microorganism during storage at $10^{\circ}C$. Naengmyon yuksu added 1.5 g of Corni fructus showed the highest sensory scores.

• Journal of Animal Science and Technology
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• v.61 no.2
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• pp.69-76
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• 2019

Maize which has very high omega-6 fatty acid content has been used as a main feed grain for Hanwoo beef production to increase marbling, and thus omega-6 to omega-3 fatty acids ratio in Hanwoo beef is expected to be biased. To elucidate the current status of omega fatty acids ratio in Hanwoo beef, fatty acid profiles of neutral lipid and phospholipid fraction were analyzed separately using 55 Hanwoo steers' longissimus dorsi muscle slaughtered at Pyeongchang, Korea from Oct. to Nov. 2015. In addition, an association study was conducted to evaluate associations between single nucleotide polymorphism (SNP) markers from references and omega fatty acid profiles in phospholipid of Hanwoo beef samples using analysis of variance (ANOVA). In neutral lipid fraction, composition of saturated and monounsaturated fatty acids was higher and polyunsaturated fatty acids was lower compared to those in phospholipid fraction. The mean n-6/n-3 ratios of Hanwoo were $56.059{\pm}16.180$ and $26.811{\pm}6.668$ in phospholipid and neutral lipid, respectively. There were three SNPs showing statistically significant associations with omega fatty acid content. GA type of rs41919985 in fatty acid synthase (FASN) was significantly associated with the highest amount of C20:5 n-3 (p = 0.031). CC type of rs41729173 in fatty acid-binding protein 4 (FABP4) was significantly associated with the lowest amount of C22:2n-6 (p = 0.047). AG type of rs42187261 in FADS1 was significantly linked to the lowest concentration of C20:4 n-6 (p = 0.044). The total n-6/n-3 ratio of the steer which has all four SNP types in above loci (27.905) was much lower than the mean value of the total n-6/n-3 ratio in phospholipid of the 55 Hanwoo steers ($56.059{\pm}16.180$). It was found that phospholipid and neutral lipid of Hanwoo have very high n-6/n-3 ratios compared to the reported data from different cow breeds. Four SNPs in genes related with fatty acid metabolism showed significant associations with the fatty acid profile of phospholipid and may have potential as SNP markers to select Hanwoo steers in terms of n-6/n-3 balance in the future.

• Journal of Digital Convergence
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• v.17 no.8
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• pp.283-291
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• 2019

The aim of investigated the role of FABP5 in the hepatic lipogenesis and lipid metabolisms. Mice were overexpressed and silenced liver FABP5 using virus particles. Mice were fed a Western-type diet or regular chow for 1week and then sacrificed mouse after 24hr fasted. Liver homogenates were used for protein analysis by Western blot and mRNA levels by RT-PCR. Hepatic and serum lipids were analysed by thin-layer chromatography. Mice fed a Western-type or high saturated fat diet revealed large increases in FABP5 expression. However, FABP5 mRNA levels were drastically reduced under fasted. Hepatic TG was significantly increased FABP5-OEAV mice, but a significantly decreased hepatic free cholesterol under fed. The discovered a substantial decrease in hepatic TG mass with FABP5 silencing. In these data, presented evidence for an important role of FABP5 in hepatic lipogenesis and hepatic TG storage. FABP5 may also be a potential target in the treatment of NAFLD, metabolic syndrome, and obesity. Furthermore, studies to which transcription factors are involved in FABP5 expression and regulation.

• The Journal of Engineering Geology
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• v.31 no.3
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• pp.381-393
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• 2021

Physical, mechanical, hydraulic, and geophysical tests were applied to validate methods of inspecting the effectiveness of grouting on an agricultural reservoir dam. Data obtained from series of in situ and laboratory tests considered four stages: before grouting; during grouting; immediately after grouting; and after aging the grouting for 28 days. The results of SPT and triaxial tests, including the unit weight, compressive strength, friction angle, cohesion, and N-value, indicated the extent of ground improvement with respect to grout injection. However, they sometimes contained errors caused by ground heterogeneity. Hydraulic conductivity obtained from in situ variable head permeability testing is most suitable for identifying the effectiveness of grouting because the impermeability of the ground increased immediately after grouting. Electric resistivity surveying is useful for finding a saturated zone and a seepage pathway, and multichannel analysis of surface waves (MASW) is suitable for analyzing the effectiveness of grouting, as elastic velocity increases distinctly after grouting injection. MASW also allows calculation from the P- and S- wave velocities of dynamic properties (e.g., dynamic elastic modulus and dynamic Poisson's ratio), which can be used in the seismic design of dam structures.