• International Journal of Advanced Culture Technology
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• v.3 no.1
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• pp.161-168
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• 2015

This article aims to apply a friction stir spot welding for producing a lap joint of AA1100 aluminum alloy and SGACD zinc coated steel. The experiment was designed by MINITAB and then investigated the relation among the friction spot joint parameters. The experimental results are as follows. The friction spot joining could successively produce the lap joint of AA1100 aluminum alloy and SGACD zinc coated steel. Interaction between the rotate speed, the hold time and the tool insert speed affected to vary the tensile shear strength of the lap joint. The prediction of the optimized welding parameters that indicated the tensile shear strength of 1966 N was the rotated speed of 4000 rpm, the pin hold time of 6 sec, the pin insert rate of 6 mm/min with the S/N ratio of 66.56 that was higher than that of the total mean S/N ratio. The practical experiment of the predicted welding parameters indicated the tensile shear strength of 2165 N and had the S/N ratio of 66.70 that was higher than the predicted tensile shear strength.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.207-210
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• 2000

Pseudomonas oleovorans was cultivated to produce medium chain length polyhydroxyalkanoates (MCL-PHA) fram octanoic acid and ammonium nitrate as carbon and nitrogen source, respectively, by a pH-stat fed-batch culture technique. The octanoate concentration of the culture broth was maintained below 4 g/L by feeding the mixture of octanoic acid and ammonium nitrate when the culture pH rose above high limit. The effect of the ratio of octanoic acid to ammonium nitrate (C/N ratio) in the feed on the PHA production was examined. The final cell concentrations of 62.5, 54.7, and 9.5 g/L, PHA contents of 62.9, 75.1, and 67.6% of dry cell weight, and productivities of 1.03, 0.632, and 0.161 g/L/h were obtained when the C/N ratio in the feed were 10, 20, and 100 g octanoic acid/g ammonium nitrate, respectively.

• The Korean Journal of Nuclear Medicine Technology
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• v.14 no.2
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• pp.155-158
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• 2010

Purpose: $^{99m}Tc$-macroaggregated albumin (MAA) hepatic arterial perfusion scintigraphy was known for useful method to evaluate patients receiving intraarterial chemotherapy for liver cancer. This study evaluate about usefulness of normal liver on hepatocellular carcinoma (HCC) from HCC patients. This study is to see the usefullness of Hepatic Arterial Perfusion Scintigraphy (HAPS) by measuring mass size, shape, lung shunting and tumor to normal ratio (T/N ratio) in relative blood stream of HCC patients compared with HCC on normal liver. Materials and Methods: From June 2009 to September 2009, HAPS studies were performed on 7 patients (men 6, women 1, mean 64) who were diagnosed HCC. HAPS was performed after proper hepatic artery $^{99m}Tc$-MAA of 5 mCi (185 MBq) injection by catheter. We performed anterior, posterior, both lateral view, SPECT of chest and abdomen. Then we set up ROI and calculated lung shunting, T/N ratio for each count, count/pixel (mean value). Results: Tumor and liver size analyzed by ROI of anterior, posterior view are 2.0-10.8 cm (mean 3.75 cm), 8.8-18.5 cm (mean 14.6 cm). T/N ratio analyzed by total tumor and total normal mean value are 2.41-5.76 (mean 3.8). lung shunting analyzed by total liver count is 3.14-13.92% (mean 6.77%). Conclusion: HAPS with $^{99m}Tc$-MAA can evaluate mass size, location, quantitative analysis through T/N ratio. also HAPS can evaluate detection of arteriovenous shunt through lung uptake before radioisotope therapy. Therefore HAPS with $^{99m}Tc$-MAA can be useful method in aspect of evaluation and treatment of HCC.

• Journal of Korean Society on Water Environment
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• v.22 no.1
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• pp.74-82
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• 2006

In this study, development of M2-Dephanox and M3-Dephanox process has been tried to enhance the nitrogen removal of M-Dephanox process on the basis of previous study about M-Dephanox. The results showed that T-N removal efficiency of M3-Dephanox process was 8.9% or 11.3% higher than M-Dephanox or M2-Dephanox processes, respectively. This result is due to the lower $NO_3{^-}-N$ concentration in the effluent of M3-Dephanox than of M-Dephanox and M2-Dephanox processes. This results were recurrenced by PASS simulator. As result of simulation by PASS program, effluent $NO_3{^-}-N$ concentration of M3-Dephanox process was 1.4 mg/L and 3.6 mg/L lower than M-Dephanox and M2-Dephanox processes. In the study about optimization of M3-Dephanox processes by PASS program, SRT greatly affected T-N removal of M3-Dephanox process, whereas, the recycle rate and recirculation rate did little affect T-N removal efficiency of M3-Dephanox. In the study about optimization of reactors following the nitrification reactor of M3-Dephanox process, it was shown that the best optimum volume ratio of denitrification reactor, intermittently aerated reactor and anoxic reactor for the T-N removal were 29.1(%) : 32.7(%) : 38.2(%). T-N removal efficiency at this volume ratio was similar to T-N removal efficiency at the volume ratio of 36.3(%) : 36.3(%) : 27.4(%) designed for the lab-scale M3-Dephanox.

• Journal of the Korean Ceramic Society
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• v.24 no.1
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• pp.23-32
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• 1987

Synthesis of high purity ultrafine Si3N4 and ${\beta}$-Sialon powders was investigated via the simultaneous reduction and nitriding of amorphous SiO2, SiO2-Al2O3 system prepaerd by hydrolysis of alkoxides, using carbonablack as a reducing agent. In Si(OC2H5)4-C2H5 OH-H2 O-NH4OH system, hydrolysis rate increased with increasing reaction temperature and pH. Pure ${\alpha}$-Si3N4 was formed at 1350$^{\circ}C$ for 5 hrs in N2 atmosphere. In Si(OC2H5)4-Al(OC3H7)3-C6H6-H2 O-NH4OH system, weight loss increased as Si/Al ratio decreased. Single phase ${\beta}$-Sialon consisted of Si/Al=2 was formed at 1350$^{\circ}C$ in N2 and minor phases of ${\alpha}$-Si3N4, AIN, and X-phase were existed besides theSialon phase at other Si/Al ratios. The Si3N4 and Sialon powders synthesized from alkoxides consisted of uniform find particles of 0.05-0.2$\mu\textrm{m}$ in diameter, respectively.

• Journal of Chest Surgery
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• v.36 no.11
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• pp.846-851
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• 2003

Background: To clarify the clinical significance of the aortic nodes in resected non-small cell lung cancer of the left upper lobe. Material and Method: One hundred fifty six patients with resected non-small cell lung cancer of the left upper lobe were studied. Patients who received preoperative induction therapy, non-curative operation or defined as operative mortality were excluded from this study. Result: In N2 left upper lobe tumors, aortic nodes comprised 52.7% of the metastatic mediastinal lymph nodes. In single station N2 disease, a frequently metastasized station was aortic node (64.3%). 5-year actuarial survival according to the N status was 65.0% in N0, 30.4% in N1, and 17.9% in N2. There was no statistically significant difference in survival between N1 and N2 diseases (p=0.06). The patients with metastasis to aortic node alone had a comparatively good prognosis (5-year survival: 35.6%) than other N2 diseases (5-year survival: 4.6%) (p=0.01) and had a similar survival outcome as N1 diseases (p=0.97). Considering the aortic node as N1 node, 5-year survival according to the N status was 65.0% in N0, 31.2% in N1, 4.6% in N2 and significant survival difference was observed between N1 and N2 disease (p=0.00). In multivariate analysis, the male sex (hazard ratio 6.892, p=0.011) and the involvement to the aortic node alone (hazards ratio 2.799, p=0.009) were the significant factors affecting postoperative survival. Conclusion: According to the our data, involvement to the aortic node alone in left upper lobe tumors should be grouped with N1 disease because this combined category reflects the surgical outcome more accurately.

• Journal of the Korean institute of surface engineering
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• v.41 no.3
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• pp.83-87
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• 2008

This study described the effects of RF power, DC bias voltage, chamber pressure and gas mixing ratio on the etch rates of TiN thin film and selectivity of TiN thin film to $SiO_2$ with $BCl_3$/Ar gas mixture. When the gas mixing ratio was $BCl_3$(20%)/Ar(80%) with other conditions were fixed, the maximum etch rate of TiN thin film was 170.6 nm/min. When the DC bias voltage increased from -50 V to -200 V, the etch rate of TiN thin film increased from 15 nm/min to 452 nm/min. As the RF power increased and chamber pressure decreased, the etch rate of TiN thin film showed an increasing tendency. When the gas mixing ratio was $BCl_3$(20%)/Ar(80%) under others conditions were fixed, the intensity of optical emission spectra from radical or ion such as Ar(750.4 nm), $Cl^+$(481.9 nm) and $Cl^{2+}$(460.8 nm) was highest. The TiN thin film was effectively removed by the chemically assisted physical etching in $BCl_3$/Ar ICP plasma.

• Animal Bioscience
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• v.34 no.5
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• pp.895-903
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• 2021

Objective: The objective of this study was to investigate the effects of various dietary unsaturated to saturated fatty acids ratios (UFA to SFA ratios) on growth performance, carcass traits, blood lipid parameters, tissue fatty acid (FA) composition, and meat quality of finishing pigs. Methods: A total of 45 crossbred pigs ([Duroc×Landrace]×Yorkshire), with an average initial body weight of 60.3±2.4 kg, were randomly allocated to three treatment groups of 1:1, 2:1, and 3:1 dietary UFA to SFA ratios. Results: Both average daily gain and average daily feed intake of pigs were decreased linearly (p<0.05), whereas backfat thickness was decreased linearly (p<0.05) with increasing of dietary UFA to SFA ratio. Serum triglyceride and low density lipoprotein cholesterol were decreased quadratically or linearly (p<0.05) respectively, whereas high density lipoprotein cholesterol was increased quadratically (p<0.05) with increasing dietary UFA to SFA ratio. In M. longissimus thoracis, the proportion of C18:1 and monounsaturated FA was decreased linearly (p<0.05), whereas the proportion of C18:2n-6, C20:4n-6 and polyunsaturated FA (PUFA) were increased linearly (p<0.05) as dietary UFA to SFA ratio increased. In the subcutaneous adipose tissue, the proportion of SFA was decreased linearly (p<0.05), whereas the proportion of n-6 PUFA, n-3 PUFA, and the UFA to SFA ratios were increased linearly (p<0.05) with increasing of dietary UFA to SFA ratio. Meat color scores and shear force of pigs were decreased linearly (p<0.05), whereas drip loss and cooking loss were increased linearly (p<0.05) with increasing of dietary UFA to SFA ratio. Conclusion: Appropriately boosted dietary UFA to SFA ratio could be conductive to optimize blood lipid parameters and tissue FA composition. However, when the ratio is too high or too low it tends to have negative effects on growth performance and meat quality.

• Journal of Environmental Health Sciences
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• v.25 no.3
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• pp.77-82
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• 1999

This study was carried to investigate the characteristics of chloramination as a disinfection in drinking water distribution system. The raw water comes from midstream of Han river. In the range of pH 6~8, preformed chloramine of $Cl_2/NH_3-N$ ratio 5:1 had the HPC inactivation of more than 99% with lower pH and shorter contact time and available chloramine residual was decreased a little. In the chloramines of $Cl_2/NH_3-N$ ratio 3:1~5:1, the higher $Cl_2/NH_3-N$ ratio, the much inactivation of HPC was increased, but as contact time was longer, HPC inactivation of $Cl_2/NH_3-N$ ratio 3:1~5:1 were equaled. Bactericidal activity of three chlorine and postammoniation was influenced by free available chlorine completely and that of preammoniation was as follows : free chlorine ${\fallingdotseq}$ postammoniation>preammoniation>preformed chloramine.

• Journal of Nutrition and Health
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• v.30 no.3
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• pp.286-298
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• 1997

This study was aimed at examining the pattern of dietary fat intake of 120 university female students living in Kongju city in order to provide baseic data for establishing the dietary grideline of desirable fat intake. The subjects were divided into three groups according to living arrangenment ; family home(FH), or dormitory(DM), or self-boarding house(SB). Fat consumption of subjects was surveyed by two-day food records, and profiles of fatty acid and cholesterol taken were calculated based upon the data reported their contents of foods. The result was that mean daily fat intake was 42$\pm$2g for FH, 48$\pm$4g for DM and 41$\pm$3g for SB. The calorie intake by fat was 20.8, 21.5, and 20.4% respectively. The ratio of P/M/S was 1.3/1.7/1 for FH, 1.3/1.6/1 for DM and 1, .5/1.5/1 for SB. And the ratio of n-6/n-3 fatty acid was 5.2/1 for FH, 8.3/1 for DM and 7.2/1 for SB. Daily cholesterol intake was 208$\pm$20mg for FH, 223$\pm$29mg for DM and 251$\pm$27mg for SB. In addition, intake of n-3 fatty acid was 1.2$\pm$0.2g for FH, 0.9$\pm$0.1g for DM and 1.2$\pm$0.2g for DB. Considering the food source of fatty acids, saturated fatty acid and monounsaturated fatty acid were taken primarily from animal foods, especially milk and milk products, and n-6 polyunsaturated fatty acid was taken from vegetable oils and fats. As a major source of n-3 fatty acid, linolenic acid was obtained through vegetable oils and fats, and eicosapentaenoic acid and docosahexaenoic acid were provided by fishes and their products. There patterns of fatty acid intakes did not differ according to living arrangement. The above results showed that intakes of fat and cholesterol, and ratios of P/M/S and n-6/n-3 fatty acid were overall desirable in all groups. However, intake of n-3 fatty acid was low in all groups. Therefore, consumption of perilla oil, legumes and fishes as a source of n-3 fatty acid should be increased by substituting other food source which provide fats and oils because calorie intake by fat was enough in these subject.