• Computers and Concrete
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• v.19 no.5
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• pp.443-449
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• 2017

Taking high geothermal tunnels as background, the deformation of concrete for shotcrete use was studied by simulating hot-humid and hot-dry environments in a laboratory. The research is made up by two parts, one is the influence of two kinds of high geothermal environments on the deformation of shotcrete, and the other is the shrinkage inhibited effect of fiber materials (steel fibers, polypropylene fibers, and the mixture of both) on the concrete in hot-dry environments. The research results show that: (1) in hot and humid environments, wet expansion and thermal expansion happened on concrete, but the deformation is smooth throughout the whole curing age. (2) In hot and dry environments, the concrete suffers from shrinkage. The deformation obeys linear relationship with the natural logarithm of curing age in the first 28 days, and it becomes stable after the $28^{th}$ day. (3) The shrinkage of concrete in a hot and dry environment can be inhibited by adding fiber materials especially steel fibers, and it also obeys linear relationship with the natural logarithm of curing age before it becomes stable. However, compared with no-fiber condition, it takes 14 days, half of 28 days, to make the shrinkage become stable, and the shrinkage ratio of concrete at 180-day age decreases by 63.2% as well. (4) According to submicroscopic and microscopic analysis, there is great bond strength at the interface between steel fiber and concrete. The fiber meshes are formed in concrete by disorderly distributed fibers, which not only can effectively restrain the shrinkage, but also prevent the micro and macro cracks from extending.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.6
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• pp.708-718
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• 2010

The objective of the current study was to determine seasonal changes in glucose, cholesterol, non-esterified fatty acids (NEFA), serum inorganic phosphorous (SIP), calcium, magnesium and iron concentrations in Nguni and crossbred cattle on the sweet and sour rangelands of the Eastern Cape Province of South Africa. Body weights, body condition scores (BCS) and serum concentrations of energy-related metabolites and mineral profiles were determined in late cool-dry, hot-dry, hot-wet, post-rainy and early cool-dry seasons in 100 cattle raised on communal rangelands from August 2007 to May 2008. Nguni cattle had lower (p<0.05) and higher (p<0.05) serum concentrations of glucose in the hot-wet and post-rainy seasons, respectively, compared to crossbreds in the same seasons. Serum cholesterol and NEFA concentrations in Nguni were lower (p<0.05) than in the crossbreds. Nguni and crossbred cattle had higher (p<0.05) serum NEFA concentrations on the sweet rangeland during the late cool-dry season than on sour rangeland. Nguni cattle had higher (p<0.05) SIP concentration in the hot-wet season than the crossbreds. Generally, both breeds had lowest SIP concentration during the hot-wet season on the sour rangeland. The lowest magnesium and highest iron concentrations were observed in the hot-wet and post-rainy seasons, respectively, compared to other seasons. Cattle on the sour rangeland had lower (p<0.05) iron concentrations than those on the sweet rangeland. It was concluded that Nguni cattle had lower cholesterol and NEFA, and higher SIP concentrations in the hot-wet season than crossbreds and energy deficits mostly occurred during the late cool-dry season on the sweet rangeland.

• Korean Journal of Materials Research
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• v.13 no.4
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• pp.266-270
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• 2003

We studied BCl$_3$ dry etching of GaAs in a planar inductively coupled plasma system. The investigated process parameters were planar ICP source power, chamber pressure, RIE chuck power and gas flow rate. The ICP source power was varied from 0 to 500 W. Chamber pressure, RIE chuck power and gas flow rate were controlled from 5 to 15 mTorr, 0 to 150 W and 10 to 40 sccm, respectively. We found that a process condition at 20 sccm $BCl_3$ 300 W ICP, 100 W RIE and 7.5 mTorr chamber pressure gave an excellent etch result. The etched GaAs feature depicted extremely smooth surface (RMS roughness < 1 nm), vertical sidewall, relatively fast etch rate (> $3000\AA$/min) and good selectivity to a photoresist (> 3 : 1). XPS study indicated a very clean surface of the material after dry etching of GaAs. We also noticed that our planar ICP source was successfully ignited both with and without RIE chuck power, which was generally not the case with a typical cylindrical ICP source, where assistance of RIE chuck power was required for turning on a plasma and maintaining it. It demonstrated that the planar ICP source could be a very versatile tool for advanced dry etching of damage-sensitive compound semiconductors.

• Resources Recycling
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• v.14 no.2
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• pp.56-61
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• 2005

Economic feasibility for retrofitting the wet bottom ash handling system to the dry system in a existing 500MW${\times}$2 units pulverized coal thermal power plant in Korea was studied. Replacing to the dry system requires the initial capital costs of 13,415,127,000\, and saves the operating costs of 935,345,000\ per year. Economic analyses based on these results showed that the initial capital cost would not be recovered within the service life of the facilities at the interest rate of 10%, and the internal rate of return of 5.6% were obtained. Thus, the retrofitting to the dry system was not economically favorable in the current condition. However, the retrofitting would be profitable when the ash disposal cost and ash selling price were increased over 15,000\/MT or 17,000\/MT, respectively.

• Journal of The Korean Society of Grassland and Forage Science
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• v.4 no.2
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• pp.122-126
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• 1983

The allocation of the dry-matter yield in Miscanthus sineusis grasslands on soils of different water contents was investigated. The results obtained in this study can be summarized as follows; 1. The standing crops of Miscanthus sineusis grassland A (soil water content; 22.54%) and B (soil water content; 9.22%) were 2,267.12 and 943.44 g/m$^{2}$, respectively. 2. The productivity curves of the Miscanthus sineusis grassland A and B were the bell-shape and the productivity peak values were showed in September. 3. In Miscanthus sineusis grassland A and B, the reproductive allocation was represented by characteristics of production structure and dry-matter yields. 4. Allocation rates of dry-matter yields to panicle and rhizomes in Miscanthus sineusis grassland A and B were 0.6 and 1.4% and 35.4 and 46.6% respectively. 5. In these results, allocation of dry-matter yield to reproductive organs was increased in the condition of water-stress.

• Medical Lasers
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• v.8 no.2
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• pp.50-58
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• 2019

Background and Objectives Low-level light therapy (LLLT) is an application of low-power light for various purposes such as promoting tissue repair, reducing inflammation, causing analgesia, etc. A previous study suggested the effect of light emitting diode (LED) light with the wavelength of 740 nm for promoting wound healing of corneal epithelial cells. This current study aimed to confirm the effect of LLLT for managing inflammation of a dry eye disease (DED) mouse model. Materials and Methods A total of 50C57BL/6 female mice were randomly grouped into 5 groups to compare the effect of LLLT:1) Control group, 2) Only LLLT group, 3) Dry eye group, 4) LLLT in dry eye group, and 5) Early treatment group. DED was induced with 4 daily injections of scopolamine hydrobromide and desiccation stress for 17 days, and LLLT at 740 nm was conducted once every 3 days. To analyze the effect of LLLT on the DED mouse model, tear volume, corneal surface irregularities, and fluorescence in stained cores were measured, and the level of inflammation was assessed with immunohistochemistry. Results The DED mouse model showed significant deterioration in the overall eye condition. After LLLT, the amount of tear volume was increased, and corneal surface irregularities were restored. Also, the number of neutrophils and the level of inflammatory cytokines significantly decreased as well. Conclusion This study showed that LLLT at 740 nm was effective in controlling the corneal conditions and the degree of inflammation in DED. Such findings may suggest therapeutic effects of LLLT at 740 nm on DED.

• International Journal of Computer Science & Network Security
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• v.24 no.1
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• pp.163-177
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• 2024

The fingerprint image quality relies on the clearness of separated ridges by valleys and the uniformity of the separation. The condition of skin still dominate the overall quality of the fingerprint. However, the identification performance of such system is very sensitive to the quality of the captured fingerprint image. Fingerprint image quality analysis and enhancement are useful in improving the performance of fingerprint identification systems. A fuzzy technique is introduced in this paper for both fingerprint image quality analysis and enhancement. First, the quality analysis is performed by extracting four features from a fingerprint image which are the local clarity score (LCS), global clarity score (GCS), ridge_valley thickness ratio (RVTR), and the Global Contrast Factor (GCF). A fuzzy logic technique that uses Mamdani fuzzy rule model is designed. The fuzzy inference system is able to analyse and determinate the fingerprint image type (oily, dry or neutral) based on the extracted feature values and the fuzzy inference rules. The percentages of the test fuzzy inference system for each type is as follow: For dry fingerprint the percentage is 81.33, for oily the percentage is 54.75, and for neutral the percentage is 68.48. Secondly, a fuzzy morphology is applied to enhance the dry and oily fingerprint images. The fuzzy morphology method improves the quality of a fingerprint image, thus improving the performance of the fingerprint identification system significantly. All experimental work which was done for both quality analysis and image enhancement was done using the DB_ITS_2009 database which is a private database collected by the department of electrical engineering, institute of technology Sepuluh Nopember Surabaya, Indonesia. The performance evaluation was done using the Feature Similarity index (FSIM). Where the FSIM is an image quality assessment (IQA) metric, which uses computational models to measure the image quality consistently with subjective evaluations. The new proposed system outperformed the classical system by 900% for the dry fingerprint images and 14% for the oily fingerprint images.

• Journal of the Korean Society of Safety
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• v.5 no.1
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• pp.31-39
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• 1990

In this paper, the influence of the table speed, metal removal rate and grinding fluid on long wheel workpiece contact zone at high effect grinding was investigated by theoretical analyses and measuring the temperature, and discussed by the temperature distribution in grinding surface layer. Main results obtained are as follows, 1) Rega.dless of the table speed, the temperature gap of the workpiece(heat influx) is about 6-8 times as high in dry condition as in wet condition. 2) Good grinding condition can be obtained owing to the effect of grinding fluid without any burning defect under the condition of the metal removal rate(1.0mm$^3$/mm.s) in case of wet grinding. 3) When the depth from the surface layer is about 1.25-1.5mm under the condition of the slow table speed, surface temperature goes up higher as the table speed slows down, because long contact time is laked at the surface layer. 4) In case of the same metal removal rate, the lower the table speed becomes, the higher the surface temperature is, because grinding depth has a far more influence on wheel workpiece contact zone than the table speed.

• Korean Journal of Soil Science and Fertilizer
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• v.32 no.3
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• pp.304-311
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• 1999

This experiment was conducted to find out the optimum condition of aeration rates for removal of malodor and to improve the compost quality. The aspect of ammonia emission and amounts of volatilization were investigated in the enclosed composting reactor of 242 liters piled with mixed materials of dairy manure and rice straw, which adjusted to 65% of initial moisture content and controlled by four different aeration rates. Mature temperature increased suddenly in initial composting time and decreased with Increasing aeration rates. The treatment of $1.79l\;min^{-1}kg\;dry-solids^{-1}$ results in overcooling and rapid drying of composting materials because of too much aeration. The average concentration of ammonia emitted from composting for 24 days was the range of 25.3 to $239.8mg\;l^{-1}$ and was highest in the treatment of $0.09l\;min^{-1}kg\;dry-solids^{-1}$, followed by 0.90. 0.18 and $1.79l\;min^{-1}kg\;dry-solids^{-1}$. The range of maximum concentration by different aeration rates was $335{\sim}2279mg\;l^{-1}$ and it wan highest in the treatment of $0.09l\;min^{-1}kg\;dry-solids^{-1}$, followed by 0.18, 0.09 and $1.79l\;min^{-1}kg\;dry-solids^{-1}$. Relationship between the ammonia concentration emitted and temperature matured under different aeration rates showed an exponential positive correlation with 1% significance and had a trend of clear increase in ammonia concentration with increasing temperature over $50^{\circ}C$. Most of ammonia volatilized within plays after composting. The volatilization rate of ammonia ranged from 0.056 to 0.453 per dry solids of materials and it was highest in the treatment of $0.09l\;min^{-1}kg\;dry-solids^{-1}$, followed by 0.18, 0.09 and $1.79l\;min^{-1}kg\;dry-solids^{-1}$. Amounts of ammonia volatilized under composting condition of this experiment was estimated to be highest in the aeration range of 0.9 to $1.0l\;min^{-1}kg\;dry-solids^{-1}$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.6
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• pp.920-926
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• 1998

To investigate the effects of yellow loess on the microbial community after applying into C. polykrikoides as a red tide centrol method during decomposition process, we conducted this study using microcosm experiments, which consisted of sediment collected from Jinhae and Masan bay. The composition, number of bacteria and respiratory electron transport system activity (ETSA) were analyzed. The number of heterotrophic bacteria examined in the samples of both stations reached maximum value within 12 hrs with $10^7$ cells/dry g, independent with the yellow loess applied. In addition, a differenee in the variation of heterotrophic bacterial composition was not observed by adding the yellow loess, and Vibrio spp. always appeared during the culture periods, However, in day 8 culture, the sulfate reducing bacteria was $3.8\times10^7$ cells/dry g in Masan bay and $5.5\times10^6$ cells/dry g in Jinhae bay samples without yellow loess, and these were 120, 350 fold-and 160, 420 fold-increased when yellow loess was added (1 : 1, 1 : 2). The average ETSA was 6.8$\~$7.6 $\mu$g formazan $h^{-1}$ dry $g^{-1}$ independently with yellow loess in aerobic condition for both samples, but activity was decreased by addition of yellow loess in anaerobic. Thus the addition of yellow loess to marine sediment seems to have an effect to inhibit the anaerobic decomposition process and growth of sulfate reducing bacteria which lead to the bad condition of marine environments.