• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.3
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• pp.833-841
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• 2013

In the case of composite material, a variety of characteristics were expressed depending on the materials that were composed of. In this study, the materials showing non-linear shear behavior were investigated among FRP composite. Each specimen was designed and analyzed according to ASTM D4255 method: regulations on the 2-rail. The dependent variables included in this experiment were a variety of fiber, fiber volume ratio, fiber array direction, temperature, material homogeneity. For determination of characteristics based on the fiber array, fiber array direction of 0, 30, 45, and 60 degrees were selected for test specimen. Temperature of 25, 40, 60, and $80^{\circ}C$ were considered for investigation of FRP materials'shear behavior based on the external temperature. Nonlinear shear behavior was observed throughout the FRP composite material in this study. Also, using vinyl ester resins, high fiber volume ratio, and fiber array direction of 45 degree appeared to show the most prominent nonlinear shear behavior. As for the findings related to the temperature change, non-linear behavior was decreased as the external temperature increased. For factory manufactured product, non-linear behavior was relatively at parity in comparison to the behavior found in the hand lay-up FRP composite specimen.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.6
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• pp.767-775
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• 2019

Objective: The purpose of this study was to evaluate the effect of rapeseed and linseed oil supplementations on performance and meat quality of lambs. Methods: The experiment was conducted on 18 growing (100-day-old) lambs of $19.7{\pm}1.9kg$ live weight, assigned to 3 groups of 6 animals each. Control lambs were fed meadow hay and concentrate alone. Experimental animals additionally received rapeseed or linseed oils at a dose of 50 g/d. The lambs were slaughtered at an average body weight of $35.7{\pm}0.5kg$. Results: The dressing percentage was higher in lambs fed rapeseed oil. Total saturated fatty acids (SFA) and C15:0, C16:0, C17:0, C21:0, C24:0 were lower in longissimus dorsi muscle (MLD) in lambs fed linseed oil. Supplementation of diet with linseed oil decreased concentrations of total monounsaturated fatty acids and C16:1, C17:1, C18:1 cis-9 in MLD. The concentrations of n-3 polyunsaturated fatty acids (PUFA) and C18:3 n-3, C20:5 n-3 in MLD were higher in lambs fed linseed oil than in other groups. Oils supplementation to diets resulted in increased concentration of C22:6 n-3 in MLD. The inclusion of linseed oil into the diet increased the contents of total PUFA, n-3 PUFA and C18:3 n-3, C20:5 n-3, C22:6 n-3 in semitendinosus muscle in comparison to control. A tendency towards a lower n:6/n:3 ratio in MLD was observed when lambs were supplemented linseed oil. Conclusion: The supplementation of linseed oil to diets seems to reduce the concentration of SFA and increase the concentration of n-3 PUFA. The n-6/n-3 ratio is an important nutritional factor, and its value has been favorably decreased below 2, thereby achieving an important target related to human health. Due to these changes carcass fatty acid profile was improved, and so enhanced lamb meat healthy properties.

• Korean Chemical Engineering Research
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• v.50 no.3
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• pp.449-454
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• 2012

Economic feasibility of the process for a coal extraction under mild condition, which will produce ash-free coal at a temperature lower than that of coal softening, was analyzed. To this end, the plant of 6000 t/d in capacity was assumed to be constructed near a coal mine in Indonesia, and the IRR, NPV, B/C ratio, and DPP of the plant were calculated based on $96 million investment cost and 15 years service life. The IRR, NPV, B/C ratio, and DPP of the plant were calculated to be 31%, $87 million, 1.08, and 3.9 years, respectively, and which satisfied the evaluation criteria of investment. The economic feasibility of the plant was mainly dependent on the price of the coal initially fed and the residue coal remaining after the extraction, according to sensitivity analysis.

• Journal of the Korean Society of Tobacco Science
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• v.29 no.1
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• pp.14-22
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• 2007

This study was conducted to investigate the effect of the total sugar contents on chemical, smoke and sensory properties and to estimate the desirable chemical composition contents from sensory properties in flue-cured leaf tobacco. The leaves used in the study were in 2005 and in $1997{\sim}2006$ crop year. Nicotine and total nitrogen contents, filling value, impact, irritation and bitterness were reduced with increasing the total sugar contents of B2O(leaf) and C2L(cutters), whereas tar and CO contents and puff number were increased. The desirable sugar contents estimated from the best overall tobacco taste of smoke were 25.9% in B2O and 26.9% in C2L. All of regression equations among total sugar/nicotine ratio, total sugar, nicotine and total nitrogen contents were significant($p{\leqq}0.05$). There were no significant difference between the 4 grade(A2O, B2O, C2L, D2L) average and the whole plant(12 grade) average contents in total sugar, nicotine and total nitrogen contents. All of regression equations between the ratio of each grade content to the average content of twelve grades and stalk position[number ; from bottom(1) to top(12)] in total sugar, nicotine and total nitrogen contents were significant($p{\leqq}0.05$). The estimated desirable chemical properties which based on the best overall tobacco taste were 23.2% of total sugar, 2.39% of nicotine, 9.7 of total sugar/nicotine ratio, 2.57% of total nitrogen, 1.08 of total nitrogen/nicotine ratio in average of four grades. With decrease the total sugar content from 32.0% to 24.0%, filling value was enhanced by 14.1% in average of B2O and C2L, also tar and CO contents of smoke were decreased by 13.2% and 10.5%, respectively. These results suggest that the estimated desirable chemical composition contents may be useful to produce good leaf tobacco, and to enhance filling value and to reduce tar and CO contents of smoke in flue-cured leaf tobacco.

• Nutrition Research and Practice
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• v.9 no.6
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• pp.619-627
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• 2015

BACKGROUND/OBJECTIVES: Colitis is a serious health problem, and chronic obesity is associated with the progression of colitis. The aim of this study was to determine the effects of natural raw meal (NRM) on high-fat diet (HFD, 45%) and dextran sulfate sodium (DSS, 2% w/v)-induced colitis in C57BL/6J mice. MATERIALS/METHODS: Body weight, colon length, and colon weight-to-length ratio, were measured directly. Serum levels of obesity-related biomarkers, triglyceride (TG), total cholesterol (TC), low density lipoprotein (LDL), high density lipoprotein (HDL), insulin, leptin, and adiponectin were determined using commercial kits. Serum levels of pro-inflammatory cytokines including tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), interleukin (IL)-$1{\beta}$, and IL-6 were detected using a commercial ELISA kit. Histological study was performed using a hematoxylin and eosin (H&E) staining assay. Colonic mRNA expressions of TNF-${\alpha}$, IL-$1{\beta}$, IL-6, inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2) were determined by RT-PCR assay. RESULTS: Body weight and obesity-related biomarkers (TG, TC, LDL, HDL, insulin, leptin, and adiponectin) were regulated and obesity was prevented in NRM treated mice. NRM significantly suppressed colon shortening and reduced colon weight-to-length ratio in HFD+DSS induced colitis in C57BL/6J mice (P < 0.05). Histological observations suggested that NRM reduced edema, mucosal damage, and the loss of crypts induced by HFD and DSS. In addition, NRM decreased the serum levels of pro-inflammatory cytokines, TNF-${\alpha}$, IL-$1{\beta}$, and IL-6 and inhibited the mRNA expressions of these cytokines, and iNOS and COX-2 in colon mucosa (P < 0.05). CONCLUSION: The results suggest that NRM has an anti-inflammatory effect against HFD and DSS-induced colitis in mice, and that these effects are due to the amelioration of HFD and/or DSS-induced inflammatory reactions.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.43 no.4 s.346
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• pp.1-7
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• 2006

AlN thin films have been fabricated by using RF magnetron sputtering method and their crystal orientations, microstructures and piezoelectric properties have been investigated with variation of the $Ar/N_2$ gas ratio and the substrate temperature. Particularly, when the $Ar/N_2$ gas ratio and the substrate temperature are 10/10 (sccm) and $400^{\circ}C$, respectively, the AlN thin film exhibits the highest (002) orientation. The result of the surface roughness measurement by using AFM shows that the surface roughness becomes better as the partial pressure of $N_2$ increases at the substrate temperature of $400^{\circ}C$ and it becomes the smallest value of 2.1 nm when $Ar/N_2$ is 0/20 (sccm). The AFM measurement also shows that when $Ar/N_2$ is 10/10 (sccm) shows that surface roughness becomes better as the substrate temperature increases from room temperature up to $300^{\circ}C$ and then it becomes worse as the substrate temperature goes up from $300^{\circ}C$. At the substrate temperature of $300^{\circ}C$ and $Ar/N_2$=10/10 (sccm), the surface roughness is 3.036 nm. The piezoelectric constant ($d_{33}$) of AlN thin film is measured by Pneumatic probe method. The measurement shows that the AlN thin film with the highest (002) orientation, fabricated at $Ar/N_2$=10/10 (sccm) and the substrate temperature of $400^{\circ}C$, has the best Piezoelectric constant ($d_{33}$) of 6.01 pC/N.

• Resources Recycling
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• v.18 no.4
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• pp.62-69
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• 2009

We researched separation of mixed waste acids with HF, $CH_3COOH$, $HNO_3$ that were produced during a semiconductor wafer process to recycle these acids. At first, we manufactured the fluoride compound in form of $Na_2SiF_6$ by precipitating HF using $NaNO_3$ and Si powder. The concentration of HF was reduced from the initial concentration of 127 g/L to 0.5 g/L with an HF recovery ratio of 99.5%. After the manufacture of $Na_2SiF_6$, the concentration of $HNO_3$ and $CH_3COOH$ demonstrated 502 g/L and 117 g/L respectively. Following these findings we added NaOH in this $CH_3COOH/HNO_3$ mixed acid in order to obtain pH=4. Next we separated the $CH_3COOH$ and recoverd it through the use of vaccum evaporation at -440 mmHg, $95^{\circ}C$. The concentration of the recovered $CH_3COOH$ was approximately 15% and the recovery ratio of $CH_3COOH$ was over 85%. We precipitated the $NaNO_3$ by cooling the concentrated solution to $20^{\circ}C$ with a $HNO_3$ recovery ratio of over 93%. We confirmed that only $Na_2SiF_6$ and $NaNO_3$ were manufactured by XRD analysis after drying these precipitants at $90^{\circ}C$. The precipitants demonstrated a purity of approximately 97% and 98% respectively. Therefore, the purity of the precipitants proved to be similar to that of commercial products.

• Journal of Food Hygiene and Safety
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• v.22 no.4
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• pp.243-247
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• 2007

A selective analytical method of headspace-GC/MS has been applied to determine levels of benzene in beverages. Food samples were 85 including 2 fruit juices, 6 fruit beverages, 11 carbonated beverages, 55 mixed beverages, and 4 beverage concentrations, and 7 extracted beverages. For phase equilibration of headspace, sample was stirred at $40^{\circ}C$ for 30 min. The oven temperature was $60^{\circ}C$ and elevated to $180^{\circ}C$ at $15^{\circ}C/min$. The internal standard was benzene-d6. The identification was done by the selected target ions such as m/z 51, 77, and 78 and the confirmation was done by the response ratio of m/z 77 to m/z 78 between sample and standard. The overall recoveries were ranged from 91% to 101% and the limit of quantification was $1{\mu}g/kg$. The average level of benzene were $5{\mu}g/kg$ for fruit beverages, $2{\mu}g/kg$ for carbonated beverages, $7{\mu}g/kg$ for mixed beverages and $7{\mu}g/kg$ for extracted beverages.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.3
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• pp.611-618
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• 2016

A $3{\times}2$ factorial experiment was conducted to investigate effects of water temperature and feeding rate on growth and body composition of olive flounder. Triplicate groups of fish (initial body weight of 118 g) fed a extruded pellet (55% protein and 4708 cal/g) to satiation and at restricted feeding rates of 0.25 and 0.4% body weight per day (BW/d) at the different water temperatures (13 and $18^{\circ}C$) for 9 weeks. Weight gain increased significantly with increase in feeding rates at each temperature. Weight gain of fish fed to satiation was significantly higher at 18 than $13^{\circ}C$, whereas, that of fish fed at 0.25 and 0.4% BW/d were significantly or slightly lower at 18 than $13^{\circ}C$. Feed efficiency and protein efficiency ratio of fish fed to satiation were not significantly different between 13 and $18^{\circ}C$, but those of fish fed at 0.25 and 0.4% BW/d were significantly higher at 13 than $18^{\circ}C$. The major finding of this study is that satiation feeding is efficient for optimal growth and feed efficiency of grower oliver flounder (116-164 g) in suboptimal water temperatures. The maintenance feeding ration which is zero growth performance, were 0.30 and 0.41% BW/day at 13 and $18^{\circ}C$, respectively. In the restricted feeding regime, compromised growth of fish were worsen in higher water temperature ($18^{\circ}C$ vs. $13^{\circ}C$). It might be related to high metabolic rate of fish that spend more energy for maintenance metabolism. Based on these results, we suggest that a satiation feeding regime is recommended for a productive growth of grower olive flounder in the suboptimal temperature.

• Bulletin of the Society of Naval Architects of Korea
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• v.27 no.4
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• pp.58-66
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• 1990

A series of test was performed measuring the failure strength and failure mode of Gr/Pi, $[0^{\circ}/45^{\circ}/90^{\circ}/-45^{\circ}]_s$ laminate containing a single pin loaded hole. The finite element method is applied to calculate the stress distribution in the laminates, then the failure load and the failure mode were predicted by means of the characteristic length. 12 different geometric variations were developed to analyze the effects of the ratio of specimen width to hole diameter (W/d) and ratio of edge distance to hole diameter (L/d). X-Ray of NDE methods were utilized in finding out the initial defects, damage and the fracture mechanism, and SEM(Scanning Electron Microscopes) was used the evaluation of the fracture mechanism and crack propagation around hole under tension pin loading. $[0^{\circ}/45^{\circ}/90^{\circ}/-45^{\circ}]_s$ laminate are found to be most sensitive to W/d but not so influenced by L/d. The failure mode and tensile strength predicted by the model show agreement with experiment data for pin loading bolted jointed test except range of $L/d{\leqq}3$.