• Journal of Korean Society of Water and Wastewater
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• v.11 no.2
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• pp.112-127
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• 1997

The purpose of this study is to get optimum operating factors of Upflow Anaerobic Sludge Blanket (UASB) reactor by introducing methods that make it to reduce inhibition possible in each process wastewater treatment. The used substrates, concentrated corn starch liquid (CSL) wastewater, modified starch, filtering and decoloring wastewater, ion refining wastewater, and mixed wastewater including modified starch and not including modified starch, are generated from molasses process. The seeding sludge is the digested sludge that had been applied to molasses wastewater. Batch test to reduce the inhibition factors that might be existed in each wastewater was examined. Based on the this test, the optimum operating factors according to alkalinity and pH variation was studied through the continuous test using three 5.5 L UASB reactor. The first reactor added $NaHCO_3$ to control alkalinity. The hydraulic retention time (HRT) reduced to 8 hours and the organic loading rate increased gradually. The second reactor changed the pH of influent from 7.0 to 6.0 using NaOH. The third reactor was operated without changes to compare the above two reactors. As the result, the inhibition in concentrated CSL wastewater was removed by adding iron (II). When trace metals were added to mixed wastewater not including modified starch, the digestability by gas production rate increased to more fifty percentage than mixed wastewater that was not adding the trace metals. The reason that the inhibition did not decreased in spite of adding trace metals and nutrients was influenced by high concentration generated during the acid fermentation. The UASB reactors using the mixed wastewater with the most effective performance were operated as 500 mg/L as $CaCO_3$ alkalinity and 6.0 pH at steady state, and at this time, the gas production rates were 283 and 311mL gas/g $COD_{added}$. The COD removal rates were 84.7 and 86.3%, respectively.

• Journal of Environmental Health Sciences
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• v.40 no.2
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• pp.127-136
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• 2014

Objectives: This study was conducted to investigate the removal of high odor concentration from swine wastewater treatment facility by full scale biofilter using liquid with deodorant mixed with earthworm cast and distillery sludge. Methods: The supply of the culture liquid to the microorganism on the media in the biofilter increases the activity and growth of biomass. The experimental equipment was biofilter tower with treatment capacity of 90 m 3/min. The experimental conditions included gas flow of $60m^3/min$, retention time of 20 sec, and gas/liquid ratio of 67. Results: With changing season from winter to summer, the inlet odor concentration of ammonia increased from 2.5 ppm to 29 ppm, and of hydrogen sulfide from 21 ppm to 91 ppm, respectively. The odor treatment system with biofilter using the culture liquid was stable when the high loading rate increased and showed excellent removal grade with an average of 96.7% for ammonia, and an average of 93.7% for hydrogen sulfide. The pH and SCOD in the recirculating culture liquid near the bottom of the biofilter tower decreased with operation time, but its influence on the odor removal rate was negligible, because the organic matter (SCOD) was replaced by some culture liquid supplied 2-4 times per day. Conclusions: The biofilter using culture liquid could successfully remove high odor concentration which was generated from swine wastewater treatment facility.

• Journal of Electrochemical Science and Technology
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• v.2 no.2
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• pp.97-102
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• 2011

Different amounts of excess lithium in the range of x = 0~0.3 were added to $Li_{1+x}[Mn_{0.720}Ni_{0.175}Co_{0.105}]O_2$ cathode materials synthesized using the co-precipitation method to investigate its microstructure and electrochemical properties. Pure layered structure without impurities was confirmed in the XRD pattern analysis and increasing peak intensity of $Li_2MnO_3$ was observed along with the addition of over 0.2 mol Li. The initial discharge capacity of the stoichiometric composition was determined to be 246 mAh/g, while the discharge capacity of the addition of 0.1 mol Li was obtained to be 241 mAh/g, which was not significantly different from that of the stoichiometric composition. However, the discharge capacities decreased dramatically after the addition of 0.2 and 0.3 mol Li to 162 mAh/g and 146 mAh/g, respectively. In the rate capability test, the active $Li_{1+x}[Mn_{0.720}Ni_{0.175}Co_{0.105}]O_2$ cathode material of the stoichiometric composition showed a dramatic decrease in its discharge capacity with increasing C-rate, as evidenced by the result that the discharge capacity at 5C was 13% compared with 0.1C. On the other hand, the discharge capacity of compositions containing excess lithium was improved at higher current rates. The cycling test showed that the composition containing an excess of 0.1 mol Li had the most outstanding capacity retention.

• KSBB Journal
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• v.18 no.2
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• pp.111-116
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• 2003

Hydrogen producing acidogenic microorganisms were self-immobilized using organic-inorganic hybrid polymer within 5 minutes. During the continuous tratment of synthetic wastewater at a hydraulic retention time of 20 hours, at 37$^{\circ}C$, pH 5.0, the self-immobillized granules were maintained in a stirred tank reactor. The black colored granules gradually became milky. Image analysis showed that the mean diameter of the milky colored granules ranged from 1.5 to 20. mm. The maximum bio-gas procuction rate was 380 ml/L/hy and the concentration of H$_2$was around 50%, while no methane was detected. Granular ECP was extracted and its content was measured to elucidate the role of the organic-inorganic hybrid polymer. Further increases of granule concentration are expected to increase the hydrogen production rate.

• Carbon letters
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• v.15 no.3
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• pp.171-179
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• 2014

An attempt was made to investigate the effect of the preparation temperature on the electrocapacitive performance of polypyrrole (PPY)/graphene oxide (GO) nanocomposites (PNCs). For this purpose, a series of PNCs were prepared at various temperatures by the cetyltrimethylammonium bromide-assisted dilute-solution polymerization of pyrrole in presence of GO (wt%) ranging from 1.0 to 4.0 with ferric chloride as an oxidant. The formation of the PNCs was ascertained through Fourier-transform infrared spectrometry, X-ray diffraction spectra, scanning electron microscopy and simultaneous thermogravimetric-differential scanning calorimetry. The electrocapacitive performance of the electrodes derived from sulphonated polysulphone-bound PNCs was evaluated through cyclic voltammetry with reference to Ag/AgCl at a scan rate (V/s) ranging from 0.2 and 0.001 in potassium hydroxide (1.0 M). The incorporation of GO into the PPY matrix at a reduced temperature has a pronounced effect on the electrocapacitive performance of PNCs. Under identical scan rates (0.001 V/s), PNCs prepared at $10{\pm}1^{\circ}C$ render improved specific conductivity (526.33 F/g) and power density (731.19 W/Kg) values compared to those prepared at $30{\pm}1^{\circ}C$ (217.69 F/g, 279.43 W/Kg). PNCs prepared at $10{\pm}1^{\circ}C$ rendered a capacitive retention rate of ~96% during the first 500 cycles. This indicates the excellent cyclic stability of the PNCs prepared at reduced temperatures for supercapacitor applications.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.8 no.4
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• pp.59-67
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• 1988

Anaerobic digestion at the temperature of $35-55^{\circ}C$ was conducted using an artificial sludge of uniform composition. The hydraulic retention time of 5 days was chosen because the temperature effect was effectively shown at a high loading. Inhibition of the methane fermentation decreased as the temperature increased. Acid fermentation was prevalent at the mesophilic and intermediate temperatures, while active methane fermentation took place at $55^{\circ}C$. Temperature not only affects activity of the microorganisms, but also affects physical and chemical properties of the sludge, Digestion inhibition was much reduced when the feed sludge was diluted, and active methane fermentation was possible at all temperatures. The digestion efficiency was governed by the organic loading rate as well as the hydraulic 10ading rate. No reduction of the digestion efficiency at $40-45^{\circ}C$, which had been referred to a critical temperature range, was observed. The digestion efficiency increased monotonically from mesophilic to thermophilic range. Improved settling properties of digested sludge was also recorded at higher temperatures.

• Fisheries and Aquatic Sciences
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• v.12 no.4
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• pp.311-316
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• 2009

A 10-week feeding trial with four dietary protein levels (22%, 32%, 42% and 52%) and two dietary lipid levels (8% and 17%) was conducted to investigate the optimum dietary protein and lipid levels for growth of long-nosed barbel fingerlings. Survival rate of fish was not affected by either the dietary protein or the dietary lipid level. Weight gain and feed efficiency were affected by the dietary protein level (P<0.01), but not by the lipid level, and increased with the dietary protein level at the both lipid levels. Weight gain and feed efficiency of fish fed the 52% protein diets with 8-17% dietary lipids were not significantly different from those of fish fed the 42% protein diets with 8-17% dietary lipids and 32% protein diet with 17% dietary lipid. Daily feed intake of fish was not affected by either dietary protein or dietary lipid level. Protein efficiency ratio and protein retention rate of fish fed the 32% protein diet with 17% dietary lipid were significantly higher than those of fish fed the 52% protein diets with 8-17% dietary lipids. Moisture content of fish fed the diets containing 8% lipid were higher than those of fish fed the diets containing 17% dietary lipid at each protein level. Crude lipid content of fish fed the diets containing 17% dietary lipid were higher than that of fish the fed the diet containing 8% dietary lipid at each protein level. The results of this study indicated that 32% protein and 17% lipid could be the optimum dietary level for growth of juvenile long-nosed barbel.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.1
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• pp.11-15
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• 2002

The present investigation was undertaken to study the effects of non-genetic factors and association among replacement and lifetime production traits. The data on 542 Holstein Friesian cows maintained during 1975-98 at State Cattle Breeding Project, Sector III, Hisar, were utilized. The average sex-ratio, abnormal births, mortality, culling and replacement rates on total calf born and total female calf born basis were 51.62, 8.50, 17.52, 31.05, 22.78 and 51.41 per cent, respectively. The study revealed that a minimum of 4 to 5 progenies are required per cow over its lifetime to replace itself. It indicated that each cow should produce a minimum of 2 female calves during its life so as to replace herself before being lost. The least-squares means for productive herd life, longevity and lifetime production were $1439.32{\pm}87.64$ and $2419.18{\pm}8.25$ days and $11317.95{\pm}913.15kg$, respectively. The heritability estimates for all replacement traits were very low indicating that sire selection may bring no desirable change in these traits. Heritability estimates were $0.178{\pm}0.157$, $0.288{\pm}0.184$ and $0.096{\pm}0.195$ for corresponding lifetime production traits. Breeding values and ranking of sires were generated for replacement and lifetime production traits to estimate the rank correlations between these traits. Moderate desirable rank correlations were obtained between replacement rate and lifetime production traits indicating that sires proven on the basis of milk production are also expected to have better replacement rate.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.18
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• pp.7805-7809
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• 2014

Objective: To explore the clinical efficacy and prognostic factors of chemoreduction combined with topical treatment of advanced intraocular retinoblastoma (RB). Materials and Methods: A total of 22 eyes from 17 children with RB were selected for the study and treated with chemoreduction combined with topical cryotherapy, transpupillary thermotherapy (TTT) or episcleral plaque brachytherapy. Clinical and follow-up data were retrospectively analyzed. Results: All children received 2~6 courses of chemoreduction treatment, ($4.5{\pm}0.8$ courses on average); 17 eyes from 13 children were treated by chemoreduction combined with cryotherapy or TTT and 5 eyes from 4 children with chemoreduction combined with $^{125}I$ episcleral plaque brachytherapy. The eye retention rate was 81.8% (18/22), among which 38.9% (7/18) featured restored or maintained good vision. Postoperative follow-up period was 7 to 34 months, ($18.6{\pm}5.2$ months on average). The recurrence rate was 41.2% (7/17), among which 57.1% (4/7) were controlled by supplementing or appending cryotherapy or TTT treatment during the follow-up period. The tumor basal diameter and thickness were significantly reduced (P<0.05 or P<0.01) after treatment. All children demonstrated different degrees of hair loss, 70.6% (12/17) with different degrees of gastrointestinal reactions, 5.88% (1/17) with neutropenia and 11.8% (2/17) being seriously infected during the chemotherapeutic treatment. Univariate and logistic regression analysis showed that tumor basal diameter before treatment had a significant effect on the prognosis (P<0.01). Conclusions: Chemoreduction combined with topical therapy can effectively control RB in the short term, and tumor basal diameter before treatment is an independent risk factor for prognosis.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.3
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• pp.67-74
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• 2015

BTC (Block Truncation Coding) image compression is simple to implement by hardware and has excellent edge retention capability of image, image compression techniques are widely used in LCD overdrive. In this paper, to maintain high visual quality and has high compression rate, Multi-Mode BTC (MM-BTC) algorithm is proposed. The MM-BTC has high compression rate using advanced Y-based BTC method and has high visual quality using improved 2-level and 4-level BTC method in this paper. As shown in simulation results, MM-BTC improves still image PSNR (Peak Signal to Noise Ratio) up to 2.34 dB as compared with other algorithms. When the MM-BTC is applied to LCD overdrive, MM-BTC improves moving picture PSNR up to 2.33 dB as compared with other algorithms in literature.