• Geophysics and Geophysical Exploration
• /
• v.23 no.4
• /
• pp.230-242
• /
• 2020

We performed a magnetotelluric (MT) survey to delineate the geological structures below the depth of 20 km in the Gyeongju area where an earthquake with a magnitude of 5.8 occurred in September 2016. The measured MT data were severely distorted by electrical noise caused by subways, power lines, factories, houses, and farmlands, and by vehicle noise from passing trains and large trucks. Using machine-learning methods, we classified the MT time series data obtained near the railway and highway into two groups according to the inclusion of traffic noise. We applied three schemes, stochastic gradient descent, support vector machine, and random forest, to the time series data for the highspeed train noise. We formulated three datasets, Hx, Hy, and Hx & Hy, for the time series data of the large truck noise and applied the random forest method to each dataset. To evaluate the effect of removing the traffic noise, we compared the time series data, amplitude spectra, and apparent resistivity curves before and after removing the traffic noise from the time series data. We also examined the frequency range affected by traffic noise and whether artifact noise occurred during the traffic noise removal process as a result of the residual difference.

• Asian-Australasian Journal of Animal Sciences
• /
• v.23 no.11
• /
• pp.1510-1518
• /
• 2010

The study was conducted to evaluate the effect of lighting schedule and nutrient density on growth performance, carcass traits and meat quality of broiler chickens. A total of 576 day old Arbor Acre male chickens was used with a $4{\times}2$ factorial arrangement. The four lighting schedules were continuous (23 L:1 D, CL), 20 L:4 D (12 L:2 D:8 L:2 D), 16 L:8 D (12 L:3 D:2 L:3 D: 2 L:2 D) and 12 L:12 D (9 L:3 D:1 L:3 D:1 L:3 D:1 L:3 D) and provided by incandescent bulbs. The two nutrient densities were high (H, starter diet: 13.39 MJ/kg apparent metabolisable energy (AME), 23.00% crude protein (CP); finisher diet: 13.39 MJ AME/kg, 19.70% CP) and low energy and protein level (L, starter diet: 12.03 MJ AME/kg, 20.80% CP; finisher diet: 12.14 MJ AME/kg, 18.30% CP). Houses with dark curtains and solid sidewalls were used. Chickens were randomly allocated to the 8 treatments with each treatment comprising 6 replicates of 12 chickens. Feed and water were available ad libitum. Lighting schedules showed no difference (p>0.05) in growth performance at the end of the experiment. 12 L:12 D significantly reduced (p<0.05) the concentration of malondialdehyde (MDA) compared to 23 L:1 D treatment. Intermittent lighting (IL) schedules produced higher protein content (p<0.001) in breast meat. Birds on high density diets had higher body weight (BW), feed intake (FI) (p<0.001), and feed conversion ratio (FCR) (p<0.001) throughout the experiment with the exception of 36 to 42 d. High nutrient density increased (p<0.05) abdominal fat, decreased (p<0.05) the moisture loss of meat, and reduced percentage of wings and legs. There was a significant lighting schedule${\times}$diet interaction (p<0.001) on FCR for days 8 to 14 and 15 to 21. Results indicated that IL can give similar growth performance in comparison with CL, meanwhile with positive effects on meat quality by increasing protein content and decreasing the concentration of MDA. High nutrient density resulted in greater growth performance.

• Journal of Electrical Engineering and Technology
• /
• v.6 no.4
• /
• pp.543-550
• /
• 2011

Conductive SiC-$ZrB_2$ composites were produced by subjecting a 40:60 (vol%) mixture of zirconium diboride (ZrB2) powder and ${\beta}$-silicon carbide (SiC) matrix to spark plasma sintering (SPS). Sintering was carried out for 5 min in an argon atmosphere at a uniaxial pressure and temperature of 50 MPa and $1500^{\circ}C$, respectively. The composite sintered at a heating speed of $25^{\circ}C$/min and an on/off pulse sequence of 12:2 was denoted as SZ12L. Composites SZ12H, SZ48H, and SZ10H were obtained by sintering at a heating speed of $100^{\circ}C$/min and at on/off pulse sequences of 12:2, 48:8, and 10:9, respectively. The physical, electrical, and mechanical properties of the SiC-$ZrB_2$ composites were examined and thermal image analysis of the composites was performed. The apparent porosities of SZ12L, SZ12H, SZ48H, and SZ10H were 13.35%, 0.60%, 12.28%, and 9.75%, respectively. At room temperature, SZ12L had the lowest flexural strength (286.90 MPa), whereas SZ12H had the highest flexural strength (1011.34 MPa). Between room temperature and $500^{\circ}C$, the SiC-$ZrB_2$ composites had a positive temperature coefficient of resistance (PTCR) and linear V-I characteristics. SZ12H had the lowest PTCR and highest electrical resistivity among all the composites. The optimum SPS conditions for the production of energy-friendly SiC-$ZrB_2$ composites are as follows: 1) an argon atmosphere, 2) a constant pressure of 50 MPa throughout the sintering process, 3) an on/off pulse sequence of 12:2 (pulse duration: 2.78 ms), and 4) a final sintering temperature of $1500^{\circ}C$ at a speed of $100^{\circ}C$/min and sintering for 5 min at $1500^{\circ}C$.

• Asian-Australasian Journal of Animal Sciences
• /
• v.25 no.7
• /
• pp.1003-1008
• /
• 2012

One hundred and twenty weanling pigs in experiment 1 (Exp. 1) ($6.91{\pm}0.99kg$; 21 d of age) and Exp. 2 ($10.20{\pm}1.09kg$; 28 d of age) were used in two 42-d and 35-d experiments to evaluate the effect of medium-chain-triglyceride (MCT) on growth performance, apparent total tract digestibility (ATTD) of nutrients and blood profile. In both of Exp. 1 and Exp. 2, the same dietary treatments were utilized as follows : i) negative control (NC), ii) positive control (PC), NC+antibiotics (40 mg/kg Tiamulin, 110 mg/kg Tylosin, and 10 mg/kg Enramycin, iii) MCT3, NC+0.32% (phase 1, 2 and 3) MCT, and iv) MCT5, NC+0.55% (phase 1), 0.32% (phase 2 and 3) MCT. In Exp. 1, the pigs fed MCT5 diets had higher (p<0.05) ADG compared to NC treatment during the first 2 wk. From d 15 to 28, the ATTD of energy was improved (p<0.05) by MCT3 compared to the PC treatment. No effect has been observed on the blood profiles [red blood cell (RBC), white blood cell (WBC), immunoglobulin-G (IgG), lymphocyte concentration] measured in this study. In Exp. 2, the ADG were increased (p<0.05) by the MCT5 treatment than the PC treatment from d 0 to 14. Pigs fed PC treatment diet had lower ADFI (p<0.05) and better FCR (p<0.05) than NC treatment, whereas no differences were shown between MCT treatments and NC or PC treatment from d 15 to 35 and overall phase. The ATTD of DM and nitrogen were improved (p<0.05) by the effect of MCT5 related to the NC and PC treatment at the end of 2nd and 5th wk. The pigs fed MCT3 had higher (p<0.05) energy digestibility than PC treatment. No effects were seen in the blood profiles we measured (WBC, RBC, lymphocyte and immunoglobulin-G). In conclusion, the addition of MCT in the weanling pigs diet can improve the ADG and digestibility during the earlier period (first 2 wks), but had little effect on the blood characteristics.

• Korean Journal of Materials Research
• /
• v.10 no.1
• /
• pp.55-61
• /
• 2000

The sintering characteristics of PVA-Al(III) complex added $UO_2$ pellet and AlOOH added $UO_2$pellet were compared. The major phase of PVA-Al(III) complex and AlOOH decomposed at $1000^{\circ}C$ in $H_2$atmosphere was $\theta-Al_2O_3$. Compared with the apparent density of pure $UO_2$, that of AlOOH added $UO_2$ powder was higher but that of PVA-Al(III) complex was lower. the densification of AlOOH added $UO_2$ pellet was initiated at about $800^{\circ}C$, the densification of PVA-Al(III) complex added $UO_2$ pellet was initiated at about $900^{\circ}C$ respectively. In a view of pore size distribution, the PVA-Al(III) complex added $UO_2$ pellet appeared as monomodal type, whereas the AlOOH added $UO_2$ pellet appeared as bimodal type. The grain size of AlOOH added $UO_2$ pellet was about $13\mu\textrm{m}$ but the grain size of PVA-Al(III) complex added $UO_2$ pellet was increased up to about $36\mu\textrm{m}$.

• Economic and Environmental Geology
• /
• v.24 no.4
• /
• pp.399-408
• /
• 1991

There are several tuff cones and tuff rings, now only apparent on the western shoreline in Cheju Island. The observation of their landform, bedform, particle size and sorting reveals that these deposits are mainly emplaced by base surges and/or slurries originating from Surtseyan eruption which is attributed to explosive hydrovolcanism influenced by interaction of magma with external water. These are subdivided into two groups based on the plateau basalt. It is recognized that the distal limb of early tuff cones and ring at Dangsanbong, Dansan, Sanbangsan and Hwasun (lower group) are overlain by plateau basalt, on which later tuff rigns at Suwolbong and Songaksan(upper group) further extend the distal limb from each vent. The tuff cones and tuff rings are closely associated with the evidences which shelly fragments are comprised within them, and reworked tuffs, raised beach deposits, Sinyangri formation and littoral cones are deposited around them. The evidences suggest that the Surtseyan eruption resulted from direct or indirect interaction of magma with sea water.

• Journal of Food Hygiene and Safety
• /
• v.15 no.2
• /
• pp.114-121
• /
• 2000

A study was carried out to establish a detection method for irradiated black and white pepper. Samples were packed in polyethylene bags and irradiated with 2.5, 5, 7.5, 10 and 15 kGy using a Co-60 irradiator. The samples were suspended in water, and alkalized with sodium hydroxide solution. Apparent viscosity was determined after heat gelatinization using a Brookfield DV-III rotation viscometer at 30。C with 30, 60, 90, 120, 150, 180, and 210 rpm. Means and standard deviations of the viscosities of all samples decreased by increasing the stirring speeds. The viscosities increased in all samples by increasing the concentration. Regression expressions and coefficients of viscosity which decreased with increasing irradiation dose of 10% and 13% black pepper, and 7% and 10% white pepper were 0.9531 (y=-131.29x+1,769.0), 0.9725 (y=-351.33x+4,036.0), 0.9731 (y=2,208.0e${^-0.3546X}$), and 0.9959 (y=5,116.0e${^-0.2887X}$), respectively, at 120 rpm. This trend was similar fur all stirring speeds. These results suggest that the detection of irradiated black and white pepper at various doses is possible by the viscometric method.

• Asian-Australasian Journal of Animal Sciences
• /
• v.14 no.11
• /
• pp.1598-1604
• /
• 2001

Eight $12.4{\pm}0.6kg$ initial body weight crossbred barrows were used to determine the effect of soybean galactooligosaccharides on nutrient and energy digestibility, and digesta transit time. Four dietary treatments were utilized in this trial. Treatment one was a corn-soybean meal based diet (SBM) containing raffinose and stachyose at the levels of 0.16% and 0.75%, respectively. Treatment two (control) was a corn-HP300 (soybean concentrate protein) diet. In treatments three and four, 1.1% and 2.2% commercial stachyose was added to the control diet to provide total dietary stachyose at the levels of 1% and 2%, respectively. The soybean galactooligosaccharides (raffinose + stachyose) level in treatment one was slightly lower compared to that in treatment three. Three collection periods were run with two pigs for each treatment/period. There was a 4 d adjustment period followed by a 3 d collection period. The results showed that the nitrogen retention (86.79%) of pigs fed treatment two diet was higher than that of pigs fed treatment one by 5.2% (p<0.05). The nitrogen retention of treatment three was intermediate 83.09%. The apparent fecal digestibility of all amino acids in treatment two was numerically highest, followed by treatments three and four. However, there were no significant difference among groups (p>0.05). The dry matter (DM), organic matter (OM), crude protein (CP), and crude fiber (CF) digestibility numerically decreased as the soybean galactooligosaccharides level increased, but were not significantly different (p>0.05). Chromium content in feces (from the inclusion of 0.3% chromic oxide in the diets) differed among treatments (p<0.05) at 15 h, 18 h, and 21 h after eating. This showed that the digesta transit time was differed significantly among treatments. Treatment four was the shortest, followed by treatment three, SBM and control. The results demonstrated that in the absence of antinutritional factors and soybean antigen protein, inclusion of 1% and 2% stachyose in corn-HP300 diet has no significant effect on the digestibility of DM, OM, CP, CF and amino acids. When the soybean galactooligosaccharide level in diet one and diet three were adjusted to be almost the same, antinutritional factors such as trypsin inhibitor and soybean antigen protein could decrease the nutrient digestibility and nitrogen retention rate of diet. High levels of soybean galactooligosaccharides shortened the digesta transit time in the intestinal tract. This trial suggested that the total level of soybean galactooligosaccharides (stachyose+raffinose) in the weanling piglet diet is better not to exceed 1% when common soybean meal is used as main protein source.

• Asian-Australasian Journal of Animal Sciences
• /
• v.29 no.12
• /
• pp.1710-1718
• /
• 2016

The objective of this study was to evaluate the effects of supplements with different crude protein (CP) contents on grazing cattle intake, digestibility, ruminal fermentation pattern, and nitrogen (N) metabolism characteristics during the rainy season. Five ruminal and abomasal cannulated Holstein${\times}$Zebu steers (296 kg body weight, BW) were used in a $5{\times}5$ Latin square design. The animals grazed five signal grass paddocks (0.34 ha). The five treatments evaluated were: Control (no supplement) and 1.0 g of supplement/kg BW with 0, 330, 660, and 1,000 g of CP/kg as-fed. The supplement was composed of starch, soybean meal, urea, and ammonium sulphate. There was a positive linear effect ($p{\leq}0.033$) of the CP content in the supplements on the organic matter (OM), CP, and digested OM intakes. The provision of supplements did not increase ($p{\geq}0.158$), on average, total and ruminal digestibilities of OM and CP. However, the increase in CP content in the supplements caused a positive linear effect ($p{\leq}0.018$) on ruminal digestibilities of OM and CP. Additionally, a quadratic effect of the CP contents of the supplements were observed (p = 0.041) for the ruminal digestibility of neutral detergent fiber corrected for ash and protein, with the highest estimate obtained with the CP content of 670 g/kg. The supply of supplements increased (p<0.001) the ruminal ammonia N concentration, which also changed linearly and positively (p<0.001) according to increase in CP content in the supplements. The apparent N balance and relative N balance (g/g N intake) were not, on average, changed ($p{\geq}0.164$) by the supplements supply. However, both showed a tendency of a linear increase ($p{\leq}0.099$) with increasing supplement CP content. The supplements increased (p = 0.007) microbial N production in the rumen, which also changed linearly and positively (p = 0.016) with increasing supplement CP content. In conclusion, protein supplementation in grazing cattle during the rainy season, while stimulating voluntary forage intake, results in higher efficiency of N utilization when compared to energy supplementation. This is a possible response to increased microbial protein synthesis in the rumen and improved N status in the animal body.

• Fisheries and Aquatic Sciences
• /
• v.19 no.5
• /
• pp.24.1-24.6
• /
• 2016

We determined the optimum dietary protein level in juvenile barred knifejaw Oplegnathus fasciatus in cages. Five semi-purified isocaloric diets were formulated with white fish meal and casein-based diets to contain 35, 40, 45, 50, and 60 % crude protein (CP). Fish with an initial body weight of $7.1{\pm}0.06g$ ($mean{\pm}SD$) were randomly distributed into 15 net cages (each size: $60cm{\times}40cm{\times}90cm$, $W{\times}L{\times}H$) as groups of 20 fish in triplicates. The fish were fed at apparent satiation level twice a day. After 8 weeks of feeding, the weight gain (WG) of fish fed 45, 50, and 60 % CP diets were significantly higher than those of fish fed 35 and 40 % CP diets. However, there were no significant differences in WG among fish fed 45, 50, and 60 % CP diets. Generally, feed efficiency (FE) and specific growth rate (SGR) showed a similar trend as WG. However, the protein efficiency ratio (PER) was inversely related to dietary protein levels. Energy retention efficiency increased with the increase of dietary protein levels by protein sparing from non-protein energy sources. Blood hematocrit content was not affected by dietary protein levels. However, a significantly lower amount of hemoglobin was found in fish fed 35 % CP than in fish fed 40, 45, 50, and 60 % CP diets. Fish fed 60 % CP showed the lowest survival rate than the fish fed 35, 40, 45, and 50 % CP diets. Broken-line analysis of WG showed the optimum dietary protein level was 45.2 % with 18.8 kJ/g diet for juvenile barred knifejaw. This study has potential implication for the successful cage culture of barred knifejaw.