• Journal of agriculture & life science
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• 제50권5호
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• pp.217-224
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• 2016

In this study, performance of a developed automatic punching machine considering the planting density of soybeans was evaluated in the case of the operation speed of 0.18-0.28 m/s. The performance demonstrated a rate of 320-500 ㎡/h, 260-400 ㎡/h, and 210-330 ㎡/h for the 0.20 m, 0.25 m, and 0.30 m soybean planting density, respectively. One hundred percent punching capacity was confirmed in 30 mm distance between the ground and the blade. Additionally, in the 50 mm distance condition, the performance of round, square, and hexagonal blades were observed in the range of 16.7-25.2%, 33.0-42.3%, and 54.5-100.0%, respectively. Above all, the hexagonal blade with a 60° edge angle had the most superior cutting quality demonstrating a smooth and soft cutting plane of the plastic.

• Journal of Ecology and Environment
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• 제33권3호
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• pp.187-193
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• 2010

Seed germination is a biological process that is affected by a variety of genetic and environmental factors. The cardinal temperature and thermal time are required for germination. The principal objective of this study was to identify and characterize variations in the base, optimum, and maximum germination temperatures of Haloxylon aphyllum L. from two seed sources, in order to establish models for use in predicting seeding dates. Mature H. aphyllum seeds were germinated at temperatures between 5 and $35^{\circ}C$. The germination behavior of H. aphyllum seeds to different temperature regimens in light was evaluated over a temperature range of $5-35^{\circ}C$ at intervals of $5^{\circ}C$. The rate of germination increased between base and optimum thermal conditions, and decreased between optimum and maximum thermal conditions; the germination rate varied in a linear fashion at both sub-optimal and supra-optimal temperatures. The linear regression fit the range of germination rates at $5^{\circ}C$ to $25^{\circ}C$ and $25^{\circ}C$ to $30^{\circ}C$, and thus the base temperature, optimum temperature, and maximum temperature for the germination of H. aphyllum were measured to be $0.6^{\circ}C$, $25.69^{\circ}C$, $37.90^{\circ}C$, and $1.76^{\circ}C$, $21.56^{\circ}C$, $37.90^{\circ}C$ for Qom and the Fars dune desert respectively.

• Journal of Korean Society of Environmental Engineers
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• 제33권7호
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• pp.511-515
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• 2011

The aim of this study was to investigate the efficiency of temperature, light intensity and pH on the growth rate of Chlorella vulgaris (C. vulgaris). The size of C. vulgaris (FC-16) was $3-8{\mu}m$, having round in shape. The cells of C. vulgaris (FC-16) was cultured in the Jaworski's Medium with deionized water. To evaluate the efficiency of temperature, light intensity and pH on the growth rate of C. vulgaris, six different fractions of temperature ($10^{\circ}C$, $15^{\circ}C$, $20^{\circ}C$, $25^{\circ}C$, $30^{\circ}C$, $35^{\circ}C$), various light intensities ($100-800{\mu}Em^{-2}s^{-1}$) and seven different fractions of pH (3, 4, 5, 6, 7, 7.5, 9) were prepared. The growth rate of C. vulgaris cultivation was approximately 5.2 to 5.5 times faster, the concentration of Chlorophyll a was also 5 to 5.5 times higher, and cell volume per unit area was 14% higher at $25^{\circ}C$ to $30^{\circ}C$ than those at $10^{\circ}C$. Therefore, the optimal temperature for cultivation of C. vulgaris was estimated $25^{\circ}C$ to $30^{\circ}C$. The growth rate of C. vulgaris increased slowly up to 5 days, exploded after 5 days until 15 days, and then stoped after that. The optimum cultivation period of C. vulgaris was estimated as 15 days. The optimum pH for the growth rate of C. vulgaris was determined pH 7 to 7.5.

• Transactions of the Korean hydrogen and new energy society
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• 제25권4호
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• pp.337-343
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• 2014

This study was conducted to evaluate the characteristics of dark fermentative $H_2$ production from microalgae (Chlorella vulgaris) using batch reactors under mesophilic (25, $35^{\circ}C$) and thermophilic (45, $55^{\circ}C$) conditions. The $H_2$ yield and $H_2$ production rate increased with increasing temperature. The maximum $H_2$ yield and $H_2$ production rate were 56.77 mL $H_2/g$ dcw, 3.33 mL $H_2/g\;dcw{\cdot}h$ at $55^{\circ}C$, respectively. The activation energy calculated using Arrhenius equation was 36.24 kcal/mol, which was higher than that of dark $H_2$ fermentation of glucose by anaerobic mixed culture. Although the concentration of butyrate was maintained, the concentrations of lactate and acetate increased with increasing temperature. The $H_2$ yield was linearly proportional to acetate/ butyrate ratio.

• Parasites, Hosts and Diseases
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• 제22권2호
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• pp.171-180
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• 1984

In order to provide some clues for differential diagnosis of trematode infections in fecal examination, the comparative morphology of eggs of 5 kinds of heterophyid flukes (Metagonimus yokogawai, Heterophyes heterophyes nocens, Heterophyopsis continua, Stellantchasmus falcatus and Pygidiopsis summa) and Clonorchis sinensis was studied. The eggs were obtained from distal portion of uteri of worms which were recovered from men after treatment. The characteristic shape and appearance of each kind of eggs were observed in detail under light microscope, and their length and width measured and compared one another. The results are as follows: 1. Eggs of C. sinensis are elongated ovoidal in shape with attenuated anterior end, 25.3~33. 2 (28. 3 in average) ${\mu}m$ long and 14.2~17.4(5.9) ${\mu}m$ wide with length/width ratio of 1.60~2.00 (1.78). They differ from all heterophyid eggs in that they have prominent wrinkling (muskmelon pattern) at their shell surface. 2. P. summa eggs are ovoid to pyriform in shape and characterized by the smallest size of all kinds examined, 19.8~22.9 (21.6) ${\mu}m$ long and 11.1~13.4 (12.1) ${\mu}m$ wide and the ratio 1.63~1.99 (1.78). 3. Eggs of S. falcatus are elongated ovoidal and most slender form, 25.3~29.2 (27.2) ${\mu}m$ long and 11.1~13.4 (12.5) ${\mu}m$ wide with the ratio of 2.00~2.57 (2.17). 4. Eggs of M. yokogawai are ellipsoid to elliptical in shape with round both ends, 26.9~31.6 (28.5) ${\mu}m$ long and 14.2~18.2 (16.8)${\mu}m$ wide with the ratio of 1.48~2.11 (1.70). 5. H. continua eggs are oval in shape, sometimes similar to M. yokogawai or H. h. nocen$ eggs, however, the relative breadth is broadest among all kinds, with maximum width at posterior half portion. They are 23.7~27.7 (25.0) ${\mu}m$ long, 15.8~18.9 (16.4) ${\mu}m$ wide with the ratio of 1. 33~1.75 (1.53). 6. Eggs of H. h. nocens are ellipsoid to ovoid in shape but sometimes more slender than M. yokogawai and have slightly pointed both ends. They are 23.7~29.2 (25.7) p.m long, 14.2~15.8 (15.4) ${\mu}m$ wide, and the ratio 1.50~2.06 (1.67). From the results, it is concluded that eggs, of 5 kinds of heterophyids and C. sinensis can be morphologically differentiated one another, however, careful observation and measurement on sufficient number of eggs are needed.

• Journal of the Korean Applied Science and Technology
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• 제38권5호
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• pp.1292-1301
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• 2021

The purpose of this study was to investigate the anti-pruritic activities such as cell viability and pruritus-related factor using seomaeyakssuk (Artemisia argyi H.; Seomaeyakssuk) extract on MC/9 (mouse mast cell line). Seomaeyakssuk was extracted from hot distilled water. Cell viability was assessed using MTT assay on MC/9 cells. Anti-pruritic activities were measured through changes in the levels of transcription factor (IL4 and IL31) on MC/9 cells. In addition, the expression of linked proteins and histamine was measured. The results confirmed that significant cytotoxicity does not appear in the concentration range of 25, 50, and 100 ㎍/㎖. The levels of IL4 was reduced to 12% (25 ㎍/㎖), 26% (50 ㎍/㎖) and 61% (100 ㎍/㎖). Also, level of IL31 was decreased 33% (50 ㎍/㎖) and 36% (100 ㎍/㎖). In the case of proteins levels decreased significantly IL-4 34%/69% and IL-31 36%/37% at 50 ㎍/㎖ and 100 ㎍/㎖. Histamine decreased by 22, 58% and 61%, respectively, at concentrations of 25, 50, and 100 ㎍/㎖. This results shows possibility of ADD as raw material in anti-pruritic products.

• Microbiology and Biotechnology Letters
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• 제25권3호
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• pp.328-334
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• 1997

A bioflocculant producing bacterium for wastewater treatment was isolated and identified as Lactobacillus jensenii. The bioflocculant was supposed as a polysaccharide. Lactobacillus jensenii YW-33 produced the flocculant with highest activity in the medium composed of 2% sucrose, 0.05% tryptone, 0.5% yeast extract, 0.01% K$_{2}$HPO$_{4}$, 0.01% KH$_{2}$PO$_{4}$, 0.01% NaCl, 0.005% MnSO$_{4}$, 5H$_{2}$O and 0.2% Tween 80. The optimal culture pH and temperature were 7.0 and 25$\circ$C, respectively. In the time course of production with jar fermentor, the productivity of the flocculant was increased in proportion to the cell growth and the cultivation time for maximum production was 24 hrs, showing flocculating activity of 1,130 units per ml.

• Journal of Food Hygiene and Safety
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• 제28권2호
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• pp.174-180
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• 2013

This study investigated the microbiological contamination of tomato in cultivation and distribution stage. Growth of Escherichia coli O157:H7 and Listeria monocytogens examined in tomato extracts (0.1, 1.0, and 10.0%) and incubation temperatures (5, 15, 25, and $35^{\circ}C$). In cultivation stage of tomato, total aerobic bacteria were 7.77 log CFU/g in gloves of APC (Agricultural Products Processing Center) worker and Bacillus cereus were 0.33 log CFU/g at nutrient tank, respectively. And Staphylococcus aureus, Salmonella spp., were not detected. After APC stage, total aerobic bacteria were significantly higher compared with before-APC stage. Among of general, pesticide-free and organic produce in tomato were no significant difference in microbial contamination. Coliforms of tomato in small vinyl package were significantly higher when compared to tomato in whole boxes package. There was no significant difference in bacteria count between unwashed tomato and washed tomato using tap water for one minute. The growth of E. coli O157:H7 and L. monocytogens in tomato extracts were decreased significantly as the concentration increased, and the microbial population was reached the lowest point during storage in 10% tomato extracts concentration for 72h at $5^{\circ}C$. However, the population of E. coli O157:H7 and L. monocytogens were gradually increased at 7.33~8.51 and 7.73~8.60 log CFU/ml during storage at $15{\sim}35^{\circ}C$ for 72h, respectively.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• 제25권1호
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• pp.33-36
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• 2012

In this study, the thickness effects of $Al_2O_3$ layer on the sensing properties of $SiO_2/Al_2O_3$ (OA) stacked membrane were investigated using electrolyte-insulator-semiconductor (EIS) structure for high quality pH sensor. The $Al_2O_3$ layers with a respective thickness of 5 nm, 15 nm, 23 nm, 50 nm, and 100 nm were deposited on the 5-nm-thick $SiO_2$ layers. The electrical characteristics and sensing properties of each OA membranes were investigated using metal-insulator-semiconductor (MIS) and EIS devices, respectively. As a result, the OA stacked membrane with 23-nm-thick $Al_2O_3$ layer shows the excellent characteristics as a sensing membrane of EIS sensor, which can enhance the signal to noise ratio.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• 제13권2호
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• pp.33-39
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• 2013

In this paper, X/Ku band waveguide diplexers with H-plane T-junction for satellite communication systems is proposed and its characteristics is cinfirmed. Two frequency bands such as X(7.25 ~ 8.4 GHz) and Ku(12.25 ~ 14.5 GHz) can be separated by the proposed waveguide diplexers. A diplexers is normally including low pass filter, high pass filter and junction waveguide. To simplify the structure of the proposed diplexers, the proposed waveguide diplexers is using impedance matching technique on H-plane of the high pass filter without low pass filter. To use vertical and horizontal polarization, the proposed diplexers with orthomode transducer(OMT) characteristics is also designed. Therefore, it is confirmed that the proposed waveguide diplexers can be used as dual-band and dual-polarization diplexers for satellite communication feed systems.