• Journal of the Korea Concrete Institute
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• v.12 no.5
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• pp.25-34
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• 2000

When concrete is placed underwater, it is diluted with separating cementitious material and as a result the quality of concrete becomes poor. To solve this problem, antiwashout underwater concrete is increasingly used for the construction and repair of the concrete structure underwater. The objective of this study is to investigate the characteristics of antiwashout underwater concrete as to the mix proportion, casting and curing water through experimental researches. The unit weight of water and cement, water-cement ratio, fine aggregate ratio, unit weight of antiwashout underwater agent and superplasticizer, and casting and curing water were chosen to measure the suspended solids, pH, air contents, slump flow, unit weight of hardened concrete, and compressive strength. From this study, the incremental modulus at mix proportion design and unit weight of antiwashout underwater agent were increased more than fresh water, and it is a optimum mix proportion that the unit weight of water(and cement) is 230kg/$\textrm{m}^3$(460kg/$\textrm{m}^3$), waterOcement ratio is 50%, fine aggregate ratio is 40%, unit weight of antiwashout underwater agent is 1.2% of water contents per unit weight of concrete, and unit weight of supeplasticizer is 2.5% of cement contents per unit weight of concrete when the antiwashout underwater concrete is used for the underwater work of ocean.

• Journal of the Korean Solar Energy Society
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• v.38 no.6
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• pp.37-49
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• 2018

In this paper a new kind of unit-prefabricated building is shown. The unit-prefabricated buildings are made up living unit, energy unit, water unit. The design trend implemented the energy insulation, solar PV panels, energy storage system which are maintained for zero energy buildings. We made a prototype for zero energy flexible residential unit. The first step, we was evaluated the physical performance, insulation, airtightness. The second step, we was evaluated energy performance building to design heating and cooling system to combined PV system. As a results, the insulation performance wall was $0.18W/(m^2{\cdot}K)$. The results of air-tightness was 12.13 ACH@50 (1/h). The building energy demand ratings and solar energy generation has the possible to be ballanced.

• Journal of Aquaculture
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• v.19 no.2
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• pp.125-132
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• 2006

Black rockfish larvae and juveniles were reared for 95 days after parturition (DAP) in order to determine four enzyme activities (trypsin, pepsine-like enzyme, lipase, amylase) during ontogeny. Larvae were fed rotifers Brachionus plicatilis from 1 to 25 DAP, Artemia nauplii from 10 to 78 DAP and then gradually changed to pelleted feed from 30 DAP. Temperature was kept between $13.5{\sim}14.9^{\circ}C$. Trypsin and lipase activities were found in 2 DAP larvae ($7.0{\pm}1.5$ unit and $4.5{\pm}1.4$ unit, $mean{\pm}SD$, respectively). The evolution of both enzymes activities showed a profile marked by drastic increases between postflexion and juvenile stage. There is an increment on specific trypsin activity at 10 DAP, corresponding with the beginning of Artemia feeding. Pepsin-like enzyme activity was found at 11 DAP and increased drastically from 56 DAP, cor-responding with the initiation of juvenile stage. Amylase activity was also found at 11 DAP and maintained at a low level up to 38 DAP followed by a drastic increase from 39 DAP to 50 DAP. Considering our results of both trypsin and pepsin-like enzyme activities, it might be concluded that higher somatic growth of Sebastes inermis could be possible with the initiation juvenile of stage and the early juvenile stage is a suit-able period for feeding an artificial diet for fish.

• Journal of Korean Society of Forest Science
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• v.109 no.3
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• pp.249-258
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• 2020

The purpose of this study examined the succession by vegetation type after forest ecosystem restoration in the Baramjae area. Vegetation of the Baramjae area was classified using a survey of 81 sites from May to October 2019. The vegetation type was classified as Pinus densiflora community group with both Quercus mongolica community and P. densiflora typical community. The group unit was further classified as the Quercus dentata typical subgroup, Salix koreensis subgroup, and Q. mongolica typical subgroup. Such as Q. mongolica, Quercus variavilis in vegetation unit 1, Q. mongolica, Q. dentata in vegetation unit 2, P. densiflora in vegetation unit 3 and S. koreensis in vegetation unit 4 were shown a high importance value. The difference in species by vertical layer is explained by sere. Based on the vegetation type classification system, Detrended Correspondence Analysis was conducted to observe the trend of succession. Since restoration, vegetation unit 1 and vegetation unit 2 were considered to have developed the most extensive vegetation. In vegetation unit 2 and vegetation unit 4, many of the species found were in the early vegetation development in S. koreensis subgroup. Accordingly, vegetation in the Baramjae area can be categorized as a stepwise succession.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.38 no.1
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• pp.27-34
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• 2001

The multiplication algorithm using the primitive irreducible trinomial $x^m+x+1$ over $GF(2^m)$ was proposed by Mastrovito. The multiplier proposed in this paper consisted of the multiplicative operation unit, the primitive irreducible operation unit and mod operation unit. Among three units mentioned above, the Primitive irreducible operation was modified to primitive irreducible trinomial $x^m+x+1$ that satisfies the range of 1$x^m,{\cdots},x^{2m-2}\;to\;x^{m-1},{\cdots},x^0$ is reduced. In this paper, the primitive irreducible polynomial was reduced to the primitive irreducible trinomial proposed. As a result of this reduction, the primitive irreducible trinomial reduced the size of circuit. In addition, the proposed design of multiplier was suitable for VLSI implementation because the circuit became regular and modular in structure, and required simple control signal.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.17 no.1
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• pp.107-120
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• 2019

The decommissioning of one nuclear power plant in a multi-unit nuclear power plant (multi-unit NPP) site may pose radiation exposure risk to decommissioning workers. Thus, it is essentially required to evaluate the exposure dose of decommissioning workers of operating multi-unit NPPs nearby. The ENDOS program is a dose evaluation code developed by the Korea Atomic Energy Research Institute (KAERI). As two sub-programs of ENDOS, ENDOS-ATM to anticipate atmospheric transport and ENDOS-G to calculate exposure dose by gaseous radioactive effluents are used in this study. As a result, the annual maximum individual dose for decommissioning workers is estimated to be $2.31{\times}10^{-3}mSv{\cdot}y^{-1}$, which is insignificant compared with the effective dose limit of $1mSv{\cdot}y^{-1}$ for the public. Although it is revealed that the exposure dose of operating multi-unit NPPs does not result in a significant impact on decommissioning workers, closer examination of the effect of additional exposure due to actual demolition work is required. The calculation method of this study is expected to be utilized in the future for planned decommissioning projects in Korea. Because domestic NPPs are located in multi-unit sites, similar situations may occur.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.7
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• pp.3131-3138
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• 2016

Several studies have addressed the possible role of hepatitis C virus genotype-4 (HCV GT4) in apoptosis. However, this still not fully understood. In the current study a re-constructed clone of E1/E2 polyprotein region of the HCV GT4 was transfected into the Huh7 cell line and a human apoptotic PCR array of 84 genes was used to investigate its possible significance for apoptosis. Out of the 84 genes, only 35 showed significant differential expression, 12 genes being up-regulated and 23 down-regulated. The highest-up regulated genes were APAF1 (apoptotic peptidase-activating factor 1), BID (BH3 interacting domain death agonist) and BCL 10 (B-cell CLL/lymphoma protein 10) with fold regulation of 33.2, 30.1 and 18.9, respectively. The most down-regulated were FAS (TNF receptor super family), TNFRSF10B (tumor necrosis factor receptor super-family member 10b) and FADD (FAS-associated death domain) with fold regulation of -30.2, -27.7 and -14.9, respectively. These results suggest that the E1/E2 proteins may be involved in HCV-induced pathogenesis by modulating apoptosis through the induction of the intrinsic apoptosis pathway and disruption of the BCL2 gene family.

• Journal of Biosystems Engineering
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• v.30 no.6 s.113
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• pp.321-326
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• 2005

Tractor performance was analyzed using the data from 226 Korean-made and 107 imported tractors tested at the National Institute of Agricultural Engineering for the 25-year period from 1980 through 2004. The performance analysis included the specific volumetric fuel consumption (svfc), power per unit weight and traction coefficient evaluated from the viewpoint of PTO power level. No significant performance improvement has been made for the Korean-made tractors over the last 25 years. The average svfc for the maximum PTO power has increased by only $2.1\%$ from 1980 to 2004, resulting in 2.86 kW${\cdot}$h/L in 2004. The average maximum PTO and drawbar power per unit weight of ballasted tractors were 1.38 and 1.19 kW/kN in 2000-2004, indicating $14.0\%$ and $5.9\%$ decreases respectively from 1980 to 2004. The traction coefficient has increased by $23.1\%$ over the 25 years, resulting in 0.68 in the 2000-2004 period. Poor performance improvement was also observed from the imported tractors. In the 2000-2004 period, average svfc for the maximum PTO power, PTO power per unit ballasted weight, drawbar power per unit ballasted weight and traction coefficient of the imported tractors were respectively 3.0 kW${\cdot}$h/L, 1.34 kW/kN, 1.13 kW/kN and 0.68. PTO and drawbar power per unit weight were lower in imported tractors than the Korean-made tractors. Comparing the test results with those of tractors less than 37 kW tested at the Nebraska Tractor Test Laboratory from 1981 to 2002, the Korean-made tractors have exhibited better performance in terms of power per unit weight. However, poor performance in the svfc and traction coefficient was observed. The average svfc and traction coefficient of the Korean-made tractors were respectively $86.4\%$ and $83.7\%$ of the tractors tested at the NTTL over the same period.

• Magazine of the Korean Society of Agricultural Engineers
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• v.26 no.4
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• pp.37-51
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• 1984

The purpose of this study is to find out the determination method of designed duty of water in the rice fields through the comparison of the net unit duty of water at the late reduction division to heading stage with that at the planting stage. The data used for analysing this problem are the data of precipitation and gauge evaporation observed by Cheong-ju Meterological Center, the coefficient of evapotranspiration by College of Agriculture, Chung Buk University and the data of transplanting progressing in Boun area. The results obtained from this analysis are summarized as follows. 1.The occurring year of 1/10 probability value for available precipitation, gauge evaporation and mean maximum daily evapotranspiration during growing season is the year of 1977. 2.The 1/10 probability values of mean maximum evapotranspiration per day under the production rate of 1, 400kg/l0a and 1, 500kg/10a based on the weight of dry matters are 9. 2mm/day and 9. 6mm/day, respectively. 3.The net unit duty of water required in the fields that the maximum planting rate exists is more than the one in the fields that the planting rate is uniform in the planting stage. 4.The determination of net unit duty of water in the late reduction division to heading stage or the planting stage depends upon the daily evapotranspiration and percolation rate in the late reduction division to heading stage or the water depth required for planting and daily consumptive use of water after planting at the planting stage. Therefore the use of figure 5-(1) to figure 5-(6) can easily make the determination of the designed net unit duty of water out of above two kinds of net unit duty of water.

• Journal of Environmental Science International
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• v.30 no.1
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• pp.69-76
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• 2021

The purposes of this study were to evaluate the removal characteristics of COD, Ni, and P and to derive appropriate operating conditions for the plating wastewater according to NaOCl reaction time and pH operating conditions in the BPC unit process during the plating wastewater treatment process. As a results of evaluating the removal characteristics for raw wastewater by each BPC unit process, the removal efficiencies of COD, Ni and P in BPC 1-1 unit process were 72.8%, 99.1%, and 100.0%. Therefore, the proper reaction time of NaOCl was derived as 21.1 minutes. In order to maintain the +800 mV ORP and the reaction time of 20 minutes, the temporary injection and continuous injection of NaOCl in the BPC unit process were 13.7 mL and 18.7 mL, respectively. It was found that the temporary injection method of NaOCl reduced the chemical cost by 36.5% compared to the continuous injection method. Also, Ni showed the highest removal efficiency of 97.8% at pH 10.5. On the other hand, P showed a removal efficiency of 57.4% at pH 10.0.