• Tunnel and Underground Space
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• v.26 no.5
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• pp.409-417
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• 2016

The shale gas is emerging as one of the oil and gas resources which can replace the traditional oil and gas resources. As the shale layer where the shale gas is deposited has low permeability, the hydrofracturing method is required to improve the productivity. This study is designed to conduct the laboratory hydrofracturing test on the samples which are modeled after the drilling hole having the general drilling hole and spiral groove. And compare the initial fracturing pressure and fluid contact between them in order to the result of the hydrofracturing depending on the shape of the drilling hole. In addition, the results were compared with the numerical modeling values from 3DEC and they were also compared with the data from the advance researches. It was found from the study that rather than the contact area of the high pressures water, the force concentration depending on the form of guide hole was more effective in the hydrofracturing.

• Journal of The Korean Society of Grassland and Forage Science
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• v.15 no.4
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• pp.238-244
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• 1995

The objective of this study is to obtain the basic data for investigating the effects of organic reserves on winter survial or regrowth yield. Forage rape(Brassica napus L.) was sown on Sep. 1, 1994. Experimental plots were divided into three replicates under 6 different cutting dates(l0 days interval from Oct. 15 to Dec. 4). Field-grown palnts were sampled on the each cutting date and on the wintering period (Jan. 16) to analyze the nitrogen and non-structural cahohydrate reserves. The rate of winter survival and regrowth yield were also measured in the spring of next year. On the before wintering, dry matter yields were 152, 274, 500, 718, 776 and 981 kg/lOa, respectively, from the cutting date on Oct. 15, Oct. 25, Nov. 4, Nov. 14, Nov. 24, and Dec. 4. Cmde protein yield significantly increased as cutting date was later until Nov. 14, thereafter a significant increase did not occured. Nitrogen and starch contents per plant significnatly increased as the cutting date was later. The increasing rate of starch was greatly higher than that of nitrogen. On the wintering period, nitrogen reserves in mts were 85.3, 68.8, 47.6, 28.3, 44.3, and 55.3 mglplant, and starch reserve were 11 1.3, 75.3, 39.3, 19.6, 26.4 and 34.6 mglplant, respectively, in the plots cut on Oct. 15, Oct. 25, Nov. 4, Nov. 14, Nov. 24, and Dec. 4. It showed that carbohydrate reserves were much highly utilized than nitrogen reserves during wintering period. The rates of winter survival were 91, 83, 46, 22, 35 and 43% and regrowth yields were 692, 545, 316, 84, 127 and 140 kgD.M/lOa, respectively, in each plots. The highly significant correlation (p<0.01) between the level of organic reserves and the rate of winter survival or regrowth yield were obtained.

• Parasites, Hosts and Diseases
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• v.24 no.2
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• pp.201-204
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• 1986

A study on the effect of diethylcarbamazine (DEC) (Supatonin) against Brugia malayi infection was conducted on Cheju Island in September 1965. A total of 182 persons living in a village of Aiwol Myun, Bukcheju-Gun was examined for microfilaraemia. Microscopic examination of smears of $20{\mu}l$ of blood revealed a microfilaria positivity rate of 28.5%. At the end of September 1965, 34 confirmed microfilaria positive cases were treated with DEC at a daily dosage of 5mg/kg body weight. A full course of 12 days of drug administration divided of two rounds for 6 days each was used. The first round of treatment was given under a strict supervision of the author in order to observe carefully side-effects of the drug. The second round of treatment was given in January 1966. The microfilaria density in $20{\mu}l$ of blood of those who received the drug was checked four times; before the treatment, during the first round of the treatment, 2 weeks and 4 months after the completion of the first round. The pre-treatment mean microfilaria density of 104.6 diminished to nearly zero (only two cases with one microfilaria respectively) 2 weeks after the first round and again slightly rose up to 0.5 four months after the first round. These results indicate that DEC (Supatonin) is highly effective to eliminate the microfilaria of B. malayi. However, severe side-effects, e.g. fever (average $38.6^{\circ}C$, maximum $39.7^{\circ}C$), headache, backache and seldom abdominal discomfort etc. were observed. There were two cases of withdrawal from the scheme due to refusal.

• Asian-Australasian Journal of Animal Sciences
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• v.4 no.4
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• pp.333-339
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• 1991

Eighty-two ewes of Balochi breed, two to four years of age were used in a completely randomized design to study the effect of winter supplementation on their performance in Kalat area of Balochistan and randomly divided into two groups of 40 and 42 animals. Two treatments (T1 and T2) studied were : 250 gm/animal/day of a 50 : 50 mixture of cottonseed cake and barley grain fed from Oct. 20 to Dec. 18, 1988 plus grazing and 500 gm/animal/day of the same feed mixture fed from Oct. 9 to Dec. 18, 1988 in addition to grazing. Lucerne hay and wheat straw in a 50 : 50 ratio were provided to all the ewes for a period of one month from Jan. 6, 1989 @ 320 gm/animal/day to sustain them in severe winter. Same feeding levels to the same ewe groups were again fed from Mar. 1 to May 27, 1989. Three breeding rams stayed with the flock from Nov. 1 to Dec. 13, 1988. Lambing took place from Apr. 2 to May 12, 1989. Conception, lambing and mortality percentage was found different (P<.05) between T1 and T2 (12.5 vs 14.8 kg). The ewes on T2 maintained higher body weights throughout winter than the ewes on T1. The results are suggestive of improvement in conception rate with winter supplementation (flushing) and decrease in ewe mortality. Late-gestation and early-lactation supplemental feeding of ewes results in increases in weaning weights of their lambs.

• Tunnel and Underground Space
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• v.29 no.5
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• pp.318-331
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• 2019

A three-dimensional(3D) equivalent continuum modeling was performed to analyze hydraulic behavior of rock mass considering discontinuities by using DFN model and smeared fracture model. DFN model was generated by FLAC3D and smeared fracture model was applied by using FISH functions, which is built-in functions in FLAC3D, for equivalent continuum model of fractured rock mass. Comparative analysis with 3DEC, which is for discontinuum analysis, was conducted to verify reliability of equivalent continuum analysis by using FLAC3D. Similar results of hydraulic analysis under the same conditions could be achieved. Equivalent continuum analysis of fractured rock mass by using DFN model was implemented to compare with existing analytical methods for inflow into the tunnel.

• Journal of Electrochemical Science and Technology
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• v.14 no.1
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• pp.96-104
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• 2023

Synergistically increased oxygen evolution reaction (OER) of manganese oxide (MnO₂) catalyst is introduced with surface-modified halloysite nanotube (Fe₃O₄-HNTs) structure. The flake shaped MnO₂ catalyst is attached on the nanotube template (Fe₃O₄-HNTs) by series of wet chemical and hydrothermal method. The strong interaction between MnO₂ and Fe₃O₄-HNTs maximized active surface area and inter-connectivity for festinate charge transfer reaction for OER. The synergistical effect between Fe₃O₄ layer and MnO₂ catalyst enhance the Mn³⁺/Mn⁴⁺ ratio by partial replacement of Mn ions with Fe. The relatively increased Mn³⁺/Mn⁴⁺ ratio on MnO₂@FHNTs induced 𝜎^* orbital (e_g) occupation close to single electron, improving the OER performances. The MnO₂@FHNTs catalyst exhibited the reduced overpotential of 0.42 V (E vs. RHE) at 10 mA/cm² and Tafel slope of (99 mV/dec), compared with that of MnO₂ with unmodified HNTs (0.65 V, 219 mV/dec) and pristine MnO₂ (0.53 V, 205 mV/dec). The present study provides simple and innovative method to fabricate nano fiberized OER catalyst for a broad application of energy conversion and storage systems.

• Journal of Fisheries and Marine Sciences Education
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• v.9 no.2
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• pp.149-166
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• 1997

This thesis is studied by means of operation diary of the factory ship GAECHEOG in the Sea of Okhotsk and the Sea of Bering from Jul. 1993 to Dec. 1996, We summarize these results as follows : 1. The factory ship GAECHEOG equipped trawl winch able to haul raw fish 700M/T per day and cargo winch able to unload manufactured goods 900M/T. The crews consist of 290~330 persons. 2. Factory machineries equipped surimi making plant able to process about 150M/T per day and fish meal plant able to manufacture about 70M/T per day. 3. The fishing ground from June to Nov. was the western Bering sea lying in the eastern Kamchaka peninsula and from Dec. to May, the fishing period to gather roe of a Pollack, was the Sea of Ohotsk lying in the western Kamchaka peninsula. 4. The buying catch of fish per each voyage from Dec. to May, the fishing period gathering Pollack-roe, was about 17,000~33,000M/T and from Jul. to Oct., the fishing period gathering non Pollack-roe, was about 10,000~21,000 M/T. 5. Raw fish was the most about 33,000M/T of the 2nd voyage in 1994 and was the least about 8,300M/T of the 1st voyage in 1993. Other voyages were about 13,000~18,000M/T. 6. The Pollack buying from Jul. to Nov. in the Bering sea was 5~7 fishes for one row in pan and body length about 40~50cm, and from Dec. to May in the Sea of Ohotsk was 6~8 fishes for one row in pan and body length about 37~45cm. 7. Surimi production in the 2nd voyage in 1994 was the most about 7,300 M/T, in the 1st voyage in 1993 was the least 1,900M/T and in other voyages was about 2,500~3,800M/T. The extraction rate of surimi goods for raw fish was about 17.4~26.5%. 8. Fish meal production in the 2nd voyage in 1994 was the most about 2,300 M/T, in the 1st voyage in 1993 was the least about 780M/T and in other voyages was about 1,100~1,700M/T. The extraction rate of fish meal goods for raw fish was about 7.3~10.7%. 9. Pollack-roe production was very much from Jan. to Apr. and was about 380~700M/T per each voyage. The extraction rate of Pollack-roe for raw fish was about 1.2~4.9%.

• Journal of the Korean Electrochemical Society
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• v.3 no.4
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• pp.224-231
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• 2000

The exfoliation of graphite (layer) was progressed due to the irreversible insertion of PC molecules between graphene layers, when propylene carbonate (PC) solvent was used as the organic solvents. The problem could be mitigated by the replacement of PC by ethylene carbonate (EC). But, the freezing point of EC-based electrolyte increased due to the high freezing point of $EC(36.2^{\circ}C)$. Therefore, EC+PC mixed electrolyte is expected as a good organic electrolyte for lithium ion battery. The EC-based organic electrolyte containing PC within pertinent quantity can be expected to have high molar conductivity and reduced exfoliation of graphite layer. The dielectric constant and molar conductivity of $LiPF_6/PC+EC+DEC$ electrolyte was investigated with a variation in the PC content. The electrochemical properties of carbon electrode in the electrolyte were also investigated. Molar conductivity and dielectric constant increased linearly by increasing the PC volume fraction in the electrolyte. The results of charge-discharge test for carbon/electrolyte/Li cell indicated that the initial irreversible specific capacity(IIC) of MCMB-6-28s and MPCF3000 decreased by the addition of $0.83 vol\%$ of PC, but increased with PC content over than $0.83 vol\%$. In the case of MPCF3000 and PCG100 having less than $10 vol\%$ PC, IIC was lower than 50 mAh/g. The discharge specific capacities varied with carbon material, but did not vary with PC content in the electrolyte.

• Resources Recycling
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• v.27 no.4
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• pp.29-35
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• 2018

In this study, the electrochemical redox behavior of neodymium in non-aqueous electrolytes was investigated to confirm the possibility of neodymium metallurgy at room temperature. The non-aqueous electrolytes include ionic liquids such as $[C_4mim]PF_6$, $[C_4mim]Cl$, and $[P_{66614}]PF_6$, ethanol which are highly soluble in neodymium salts, and mixed electrolytes based on carbonate with highly electrochemical stability. The electrochemical redox properties of neodymium were better than those of other electrolytes in the case of the mixed electrolyte based on ethylene carbonate (EC)/di-ethylene carbonate (DEC). Ethanol was added to improve the physical properties of the mixed electrolyte. Thorough the analysis about ionic conductivity of EC/DEC ratio, ethanol content and $NdCl_3$ concentration, the best electrolyte composition was 50 vol% content of ethanol and 0.5 M of $NdCl_3$. Using cyclic voltametry and linear sweep voltametry, a current peak estimated at -3.8 V (vs. Pt-QRE) was observed as a limiting current of neodymium reduction. Potentiostatic electrolysis for 18 hours at room temperature at -6 V (vs. Pt-QRE) confirmed that metallic neodymium was electrodeposited.

• Nuclear Engineering and Technology
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• v.53 no.10
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• pp.3367-3378
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• 2021

The design phase and safety assessment of Generation IV liquid metal-cooled fast reactors calls for the improvement of fuel pin performance codes, in particular the enhancement of their predictive capabilities towards uranium-plutonium mixed oxide fuels and stainless-steel cladding under irradiation in fast reactor environments. To this end, the current capabilities of fuel performance codes must be critically assessed against experimental data from available irradiation experiments. This work is devoted to the assessment of three European fuel performance codes, namely GERMINAL, MACROS and TRANSURANUS, against the irradiation of two fuel pins selected from the SUPERFACT-1 experimental campaign. The pins are characterized by a low enrichment (~ 2 wt.%) of minor actinides (neptunium and americium) in the fuel, and by plutonium content and cladding material in line with design choices envisaged for liquid metal-cooled Generation IV reactor fuels. The predictions of the codes are compared to several experimental measurements, allowing the identification of the current code capabilities in predicting fuel restructuring, cladding deformation, redistribution of actinides and volatile fission products. The integral assessment against experimental data is complemented by a code-to-code benchmark focused on the evolution of quantities of engineering interest over time. The benchmark analysis points out the differences in the code predictions of fuel central temperature, fuel-cladding gap width, cladding outer radius, pin internal pressure and fission gas release and suggests potential modelling development paths towards an improved description of the fuel pin behaviour in fast reactor irradiation conditions.