• Korean Journal of Environmental Biology
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• v.19 no.2
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• pp.159-171
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• 2001

Community structure, horizontal distribution, density, and ratio between nematodes and benthic harpacticoid copepods of the meiobenthos within the sediments of inner Sihwa Lake were investigated in May 1999 and May 2000. A total of 11 and 8 classes of meiobenthic animals were identified in 1999 and 2000, respectively, which were much lower than other coastal areas. The dominant animals during both sampling periods was the nematodes, followed by sarco-mastigophorans, nauplius of crustaceans, benthic harpacticoid copepods and polychaetes. These five classes of animals comprised more than 90% of total abundance of neiobenthos presented in the samples. In 2000, a lot of polychaete larvae were identified. The most abundant animal were the size that fits in 0.063 mm sieve size. Lower density was observed upper inner part of the Sihwa Lake during both sampling periods, and higher density was observed around the Sihwa floodgates. The average density between those two numbers were observed in the samples collected in the middle of the lake. Lower nematodes to betnhic harpacticoides (N/C) ratio, a relative indicator of environmental pollution, was observed to be lower around the floodgate but higher ratios were observed in the upper inner Sihwa Lake. The present study indicated that inner upper part of the lake becomes unsuitable for the meiobenthos, and the most inner upper lake was considered to be polluted.

• Applied Chemistry for Engineering
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• v.9 no.7
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• pp.1070-1078
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• 1998

Thermodynamic analysis on carbon dioxide reforming of methane was performed using a computer program which can handle condensed species in the products, and the reforming experiments were conducted over $Al_2O_3$, $La_2O_3$, ZSM-5, MCM-41, KIT-1 supported nickel catalysts, and a commercial ICI 46-1. It was estabished that a system which consists of $CH_4$, $CO_2$, CO, $H_2$, $H_2O$, and C is appropriate for theoretical equilibrium calculations and addition of water vapor or oxygen was found to diminish the contribution of carbon dioxide in reforming. Silicate molecular sieve-supported catalysts such as Ni/ZSM-5, Ni/MCM-41, Ni/KIT-1 were effective for high $CH_4$ and $CO_2$ conversions as well as for high CO yield. Coke formation was suppressed when CaO was added as a promoter. Ni/Ca/KIT-1 which contains 10% Ni with 3% Ca showed conversion approaching equilibrium levels above $650^{\circ}C$ and maintained constant activity over 20 h. Despite increased space velocity, relatively high conversion and CO yield were observed.

• Magazine of the Korean Society of Agricultural Engineers
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• v.17 no.4
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• pp.3931-3942
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• 1975

This study was conducted to investigate the strength of soil cement for varied curing temperatures (0,10,20,30,40,50,60$^{\circ}C$) and cement content (3,6,9,12%) in four cement-stabilized soils (KY: sand, MH: sand, SS: sandy loam, JJ:loam). The experimental results obtained from unconfined compressive strength tests were as follows: 1. According to increase of curing temperature as 30,40,50, and 60$^{\circ}C$, the unconfiened compressive strength of soil cement increased, the rate of increase in the early curing period was large, and around 120 hours was suifficient curing time to complete hardening. 2. The strength at 10$^{\circ}C$ decreased to the rate of 30 to 40 percent than that of 20$^{\circ}C$ while the strength at 0$^{\circ}C$ was very small, strength of soil cement increased in cold weather unless that the temperature was below 0$^{\circ}C$ 3. The average maximum temperature, about 30$^{\circ}C$ during July and August in Korea may be recommended for a optimum construction period to increase the strength of soil cement. 4. Accelerated curing time that strength was equivalent to 28-Day norma1 curing decreased in accordance with the increase of curing temperature, and also accelerated curing decreased the effect of cement content. Accelerated curing that strength was equivalent to 28-day normal curing for soil cement of cement content 9% and temperature 60$^{\circ}C$ was 45 hours; KY, 50 hours: MH, 40 hours; SS, 34 hours; JJ. 5. According to the increase of the percent passing of No. 200 sieve, accelerated curing times became shorter to become the required stength. 6. Relation between accelerated curing times and normal curing days was showeda linear of which slope decreased in accordance with the increase of curing temperature, it may be expressed as follows: (1). 30$^{\circ}C$ t=3.6d+6(r=0.97) (2). 40$^{\circ}C$ t=3.2d-5.1(r=0.95) (3). 50$^{\circ}C$ t=2.1d-4.0(r=0.93) (4). 60$^{\circ}C$ t=1.4d+4.0(r=0.90) in which t=accelerate curing time. d=normal curing day. 7. Accelerated curing time that the strength was equivalent to 35kg/$\textrm{cm}^2$ which was the strength of cement brick was 96 hours at temperature 30$^{\circ}C$ to SS 9%, and 120 hours at temperature 50$^{\circ}C$ to JJ 9%, Consequently, a economic soil cement brick may be made in future.

• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.4
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• pp.47-54
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• 2010

This study is progressed function ratio, it's trued taste by an experiment to present data for human work light weight aggregate development that use clink ash progressed liquid limit, small success limit, wear loss in quantity, sand equivalent, sieve cutting examination. 80:20's match of function rain examination is 1.4, and that use rubble aggregate as recyeled-panit lightweight aggregate's capacity ratio increases by 1.0 increase of function rain many. Also, examination multiplied delicate flavor gradually according to increase of the mixing rate, and absorption coefficient increased. This is judged by phenomenon that appear by special quality upper recycled-panit of polystyrene bid and porosity's increase between lightweight aggregate. It is case that use aggregate of wear loss in quantity is 13.5 in sand equivalent and a wear loss in quantity experiment and although case that mix 20% increases by 14.4, this phenomenon by weak tissue of lightweight aggergate be judged. When it's as a these experiment, the statue prevention floor of a street improvement specifications is prescribing so that satisfy by sand equivalent 20, CBR 10. This is showed result that this satisfies in quality standard all in match experiment ago that see.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.5
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• pp.700-705
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• 2012

$Prunus$ $mume$ was steamed for easier removal of the pulp. The steamed fruit pulp was vacuum dried and powdered. The steamed $Prunus$ $mume$ powder (SPP) was passed through a 250 ${\mu}m$ sieve, fluidized in a fluid-bed granulator, and then granulated by top-spraying with water (SPPGW) or the extract obtained from steam (SPPGE). Then the physicochemical and sensory properties of SPP, SPPGW, and SPPGE were evaluated. The flowability of powder (angle of repose $^{\circ}$) of SPP, SPPGW and SPPGE was $23.59^{\circ}$, $11.07^{\circ}$, and $13.94^{\circ}$, respectively. The water dispersibility of SPP, SPPGW, and SPPGE was 18.69, 10.04 and 6.00 sec, respectively. Also, the overall acceptance of SPP, SPPGW and SPPGE was 3.00, 3.44 and 6.56, respectively. In conclusion, SPPGE can be used as granular steamed whole fruit pulp with good powder flowability and dispersibility, and therefore consumer acceptance.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.6
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• pp.221-228
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• 2013

It is impossible directly to find a prime number p,q of a large semiprime n = pq using Trial Division method. So the most of the factorization algorithms use the indirection method which finds a prime number of p = GCD(a-b, n), q=GCD(a+b, n); get with a congruence of squares of $a^2{\equiv}b^2$ (mod n). It is just known the fact which the area that selects p and q about n=pq is between $10{\cdots}00$ < p < $\sqrt{n}$ and $\sqrt{n}$ < q < $99{\cdots}9$ based on $\sqrt{n}$ in the range, [$10{\cdots}01$, $99{\cdots}9$] of $l(p)=l(q)=l(\sqrt{n})=0.5l(n)$. This paper proposes the method that reduces the range of p using information obtained from n. The proposed method uses the method that sets to $p_{min}=n_{LR}$, $q_{min}=n_{RL}$; divide into $n=n_{LR}+n_{RL}$, $l(n_{LR})=l(n_{RL})=l(\sqrt{n})$. The proposed method is more effective from minimum 17.79% to maxmimum 90.17% than the method that reduces using $\sqrt{n}$ information.

• Journal of the Korean Recycled Construction Resources Institute
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• v.1 no.1
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• pp.98-107
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• 2005

In other to recycle the waste concrete produced in stiu on the construction and management in highway, the recycled aggregates were experimentally examined in a practical application for anti-freezing layer and lean concrete base course. From the results, the mobile impact crusher and the eccentric-mounted cone and jaw were superior to the others for the graded aggregates. In the case of anti-freezing layer, the recycled one was easily controlled since the dry densities, contrary to natural one, were not largely changed with the moisture contents. It was found that the 7days compressive strengths of lean concrete were above the 10MPa regardless of the crushing types. From the result of testing the bearing capacity of anti-freezing layer, it was found that when the recycled aggregates mixed with natural sand would be within the required gradations, the layer meets the requirements of limitation and the percentage to passing 2-20mm sieve increased by 5~13% because the flimsy mortars on aggregate were re-crushed by vibrated-roller compactor. Although the compressive strength of lean concrete was 71~85% of the natural coarse aggregate, the recycled aggregates are applicable to the lean concrete because they largely exceeded the required strength, 5.8MPa.

• Journal of the Korean Electrochemical Society
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• v.19 no.3
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• pp.63-68
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• 2016

$Li_4Ti_5O_{12}$ is prepared through a solid-state reaction between anatase $TiO_2$ and $Li_2CO_3$ for the negative electrode active materials in quick-charging lithium-ion batteries. The small amount of carbon black (0, 0.5, 1.0, and 3.0 wt%) is added for the reduction of powder agglomeration during heat-treatment. As the amount of the added carbon black increases, the tap density of $Li_4Ti_5O_{12}$ powder gradually decreases. Furthermore, the $Li_4Ti_5O_{12}$ powder prepared with 1.0 wt% of carbon black shows the highest sieved fraction at the powder classification by 325 mesh standard sieve. The $Li_4Ti_5O_{12}$ powders with various contents of carbon black are almost same at the rate capability for the negative electrode materials in lithium-ion batteries.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.3 no.3
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• pp.107-116
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• 1983

This paper is concerned with the permeability through a decomposed granite soil layer which is influnced by change of grain sizes and crushed soils made by varied compaction energy. The change in the content of crushed soils can be described in terms of the ratio of surface area ($S_w{^{\prime}}/S_w $). The experiments were carried out to obtain the relationships of the coefficient of permeability(K) versus the optimum moisture content($w_{opt}$) by the variable head permeability test with the samples that were preapared by compaction test. The results are found as follows; (1) By the change in compaction energy, the crush ratio increased whereas the void ratio decreased with a larger maximum dry density running in parallel with the zero air void curve. (2) The ratio of surface area was $0.33(P)^{0.96}$ in $S_w{^{\prime}}/S_w $ with no relation to the compaction energy. (3) The grain size which produced the largest crush of soil particles ranged from 0.5 to 1 millimetre (4) The relationship of K versus $e^3$/1+e appeared as a straight line on the full-log-scale paper under the optimum moisture state. (5) As the compaction energy was larger, the passing percentage of #200-sieve grains increased linearly. The increment in the surface area ratio was deemed to have been caused by the decreased in the permeability.

• Korean Journal of Food Science and Technology
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• v.38 no.4
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• pp.483-487
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• 2006

In this study we investigated the effect of soybean germination on protein solubility, water and oil absorption and foaming and emulsion Properties. The soybeans were at germinated at $20^{\circ}C$ for 12 and 24 hr and then ground fine enough to Pass through a 60 mesh sieve. The germinated whole soy flour (GWSF) was relatively low in oil absorption capacity and protein solubility at pH 2 and 10 and high in water absorption capacity compared to ungerminated soy flour. Relatively low foaming capacities were measured for GWSF at pH 2 and 12 while the stabilities of GWSF were higher than that of ungerminated soy flour at pH 2-12 and setting time of 30-120 min. Emulsion capacity and stability were improved by germination at pH 10-12.