• Proceedings of the Korea Concrete Institute Conference
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• 1998.10a
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• pp.307-312
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• 1998

Recently the study on high flowing concrete which has high workability and Self-compacting is being proceeded actively in the university and corporative laboratory. There are some cases that has been applied to the field. This high flowing concrete has higher fluidity and segregation resistance than Plain of flowing concrete. And it is being focused as a remarkable know-how which can make high-quality concrete and reduction effect of labor force. This properties of high flowing concrete are influenced by the relationship of several factors; binder content, water binder ratio and unit water content. It is the aim of this study to propose reference data at mix design of high flowing concrete, after comparing and analyzing the fluidity and strength properties of high flowing concrete according to water binder content ratio and unit water content.

• Journal of Korean Society of Water and Wastewater
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• v.22 no.1
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• pp.169-174
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• 2008

In this study a trickling filter system was developed by using polypropylene media and polypropylene nylon media that has recently been developed. The experiment analyzed an ability of water purification of the two plastic media and the effects of biomass on the final effluent. As recycling ratio increases, polypropylene nylon suspender showed higher efficiency by 20%; and, when media height was lengthened twice, efficiency increased about 10%. EPS and biomass increased in proportion to the increase of recycling ratio, and bound-TOC showed a similar trend with bound-EPS (extra-cellular polymeric substances) concentration.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.04a
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• pp.261-266
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• 1998

The purpose of this study is to present the reference data on the development of undispersed underwater mortar for augered pile under various replacement ratio of fly-ash. According to the experimental results, when 10% of fly-ash is mixed under mix proportion of 1:1.5(c:s), as strength and shrinkage decrease slightly, whereas fluidity increase, high quality mortar for augered pile can be achieve in case above condition is applied.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.893-898
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• 2003

An experiment was conducted to characterize water droplet charging performance of an electrostatic spraying nozzle for an electrostatic wet scrubber. Charge-to-mass ratios, the nozzle currents divided by the mass flow rate of water were obtained with respect to the applied voltage to the ring-electrode for 2 different flow conditions. It was shown that the charge-to-mass ratio increased in proportion to the applied voltage and tended to saturate at a certain higher voltage.

• Journal of Surface Science and Engineering
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• v.29 no.3
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• pp.149-156
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• 1996

Conducting diamond-like carbon films are synthesized using Triode Magnetron Sputtering-Plasma Enhanced Chemical Vapor Deposition(TMS-PECVD), and are examined by four point probe, microhardeness tester, and scanning electron miscroscopy(SEM). As the target bias and Ar/CH$_4$, ratio increase, the electrical resitivity and microhardness of the films are found to decrease, and also, their surface morphologies tend to be rough. While the resistivities of the films are shown to increase in proportion to the increase of the substrate bias, the microhardness of the films is shown to be maximun value(1600kg/$\textrm{mm}^2$) at a certain substrate bias(-70V). We can obtain the conducting diamond-like carbon films with the microhardness of 1600(kg/$\textrm{mm}^2$) and electrical resitivity of 16($\Omega$cm) at the process condition such as target bias -400V, substrate bias -70V, and Ar/$CH_4$ ratio 20.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.04b
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• pp.731-736
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• 1998

The dynamics and Durability of Permanent Form Mortar were observed. The results were as the followings. To construct New permanent form, this study constructed permanent form with fiber mortar. In this course glass fiber and polymer, fine aggregate were substituted with river sand and crush sand. To understand material quality effect, flexible mortar and inflexible mortar were tested. According to the microstructure of polymermatrix test by SEM, higher density by Co-matrix effect from polymer addiction was observed. This is considered to increase acid-resistanc, impact proof strenght. In the test of durability of freezing and thawing, polymer mortar was proved to be water proof. It seems to be improved in its characteristics in proportion to increasing W/C ratio. When the W/C ratio is 30%, it is most effective.

• Proceedings of the KIEE Conference
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• 2006.07b
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• pp.753-754
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• 2006

In case of the synchronous reluctance motor, the torque is proportional to silency difference and the power factor is in proportion to silency ratio. This paper presents the rotor design variable that has a effect on silency difference and silency ratio for getting a maximum torque and a power factor in the synchronous reluctance motor. To carry through the object, a number of the analysis model is reduced by DOE (Design of Experiments) and the main effects are found by the FEM (Finite Element Analysis).

• Food Science and Preservation
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• v.7 no.1
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• pp.51-56
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• 2000

Quality characteristics of Satsuma mandarin (Citrus unshiu Marc.var.miyagawa) harvest on early December according to production areas and sea level altitude of Cheju were investigated. Soluble solids and flesh ratio were distributed 9.32∼12.50, 75.95%-81.3 in citrus fruits harvested in orchards located below 10m sea level altitude (lower area), and was 10.23-12.17 , 77.35%-80.29% on those over 150m sea level altitude )higher area), respectively. Acid content of citrus juice was 0.95%-1.26% in fruits harvested inlower area, and was 1.02%-1.39% in higher area. In proportion to late harvesting , Brix/acid ratio and fruits quality was improved. Soluble solids of fruits harvested in higher area were higher than those of fruits from higher area, but acid contents were on the contrary . In sensory evaluation on fruit appearance, the differences between two altitudes were not clear.

• The Journal of Fisheries Business Administration
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• v.7 no.1
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• pp.27-41
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• 1976

The results analyzed of the actual state of the stow net fisheries based on the cost expended in 1975 areas follows; The total cost of this fisheries will be 1, 672, 238 won; the production cost, 1, 588, 060 won (95%) ; the material cost in proportion to total cost (100%)408, 480won (24.4%);the labour cost, 1, 006, 480 won (60.2%) ; the expenses, 173, 100won(10.4%)and the commission and the interest payment, 84, 178won(5%). As above the commission and the interest payment doesn't need to be paid much, but only production cost should be paid in case of small scale inshore fisheries. The cost per unit of caches (per Kg) becomes 12 won, the ratio cost of sales (83.4%), the ratio of profit, 16.%. According to the adove, in case of the powered vessel; it shows a tendency of spending too much expenses owing to excessive payment of oil. And in case of nonpowered vessels, it shows a tendency of spending less expenses but still get much gains, due to the fact that the commission and the interest payment are less, and none is paid for fuel procurement.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05a
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• pp.375-378
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• 2005

In the mechanism of beam shear failure, beam action and arch action always exist simultaneously. According to a/d ratio, the proportion and contribution between these two actions to shear capacity are merely changed. Moreover, the current codes recommendations are founded on the experimental results with normal strength concrete, the applicable range of $f'_{c}$ must be extended. Based on this mechanism and new requirement, an analytical equation is proposed for shear capacity prediction of reinforced concrete beams without stirrups. To reflect contribution change of two actions, stress variation in longitudinal reinforcement along the span is considered with Jenq and Shah Model. Dowel action and shear friction are also taken into account. Size effect is included to derive more precise equation. It is shown that the proposed equation is more accurate than other empirical equations and codes. So, it can be possible that wide range of a/d ratio is considered by one equation.