• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.3
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• pp.257-266
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• 2022

This study was conducted to prepare hamburg steak (HS), cooked rice with vegetables (CRV), and white stew (WS) using Pacific anchovies Engraulis japonicus with different physical and nutritional properties as senior-friendly seafoods (SFS) and investigate their quality characteristics. The hardness values of HS, CRV, and WS were 319.5×10³, 20.4×10³and 2.1×10³ N/m², respectively. The viscosity of the WS was 12,514 mPa·s. The nutritional properties of HS, CRV, and WS were 19.7, 6.2, and 7.5 g/100 g of protein, respectively; 12.50, 83.97, and 15.96 ㎍RAE/100 g vitamin A; 1.53, 1.51, and 0.35 ㎍/100 g vitamin D; 16.96, 2.82, and 4.13 mg/100 g vitamin C; 0.40, 0.07, and 0.19 mg/100 g riboflavin; 6.68, 0.34, and 2.30 mg NE/100 g niacin; 93.6, 35.4, and 82.1 mg/100 g Ca; 290.1, 103.9, and 158.6 mg/100 g K; and 0.11, 0.02, and 0.04 mg/100 g of dietary fiber. Escherichia coli was not detected in any of the products. These results suggest that HS be classified as step 1, CRV as step 2, and WS as step 3, according to the SFS standards of the KS. Overall, the nutritional and physical properties of the products were improved.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.6
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• pp.599-605
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• 2013

The effects of water-saving irrigation on the emissions of greenhouse gases and the prokaryotic communities in rice paddy soils were investigated through a field experiment. In the Water-Saving (WS) irrigation, the water layer was kept at 2~3 cm while it was kept at 6 cm in the Continuousiy Flooding (CF) irrigation. A plot was treated with Intermittently Drainage (ID) that is drained as fine cracks on the floor were seen after transplanting. GHGs emission amounts from WS plots were reduced by 78.1% compared to that from CF plot and by 70.7% compared to that from ID plot, meaning that WS could help contribute to mitigation of the greenhouse gas accumulation in the atmosphere.

• Transactions of the Korean Society of Automotive Engineers
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• v.8 no.6
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• pp.142-155
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• 2000

A MIMO model reference control scheme incorporating the variable structure theory for a vehicle four wheel steering system(4WS) is proposed and evaluated for a class of continuous-time nonlinear dynamics with known or unknown uncertainties. The scheme employs an neural network to identify the plant systems, where the neural network estimates the nonlinear dynamics of the plant. By the Lyapunov direct method, the algorithm is proven to be globally stable, with tracking errors converging to the neighborhood of zero. The merits of this scheme is that the global system stability is guaranteed and it is not necessary to know the exact structure of the system. With the resulting identification model which contains the neural networks, it does not need higher degrees of freedom vehicle model than 3 degree of freedom model. Th proposed scheme is applied to the active four wheel system and shows the validity is used to investigate vehicle handing performances. In simulation of the J-turn maneuver, the reduction of yaw rate overshoot of a typical mid-size car improved by 30% compared to a two wheel steering system(2WS) case, resulting that the proposed scheme gives faster yaw rate response and smaller side angle than the 2WS case.

• Journal of Radiation Protection and Research
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• v.48 no.4
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• pp.184-196
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• 2023

Background: Radiation protection is crucial in various fields due to the harmful effects of radiation. Shielding is used to reduce radiation exposure, but gamma radiation poses challenges due to its high energy and penetration capabilities. Materials and Methods: This work investigates the radiation shielding properties of polyvinylidene fluoride (PVDF) samples containing different weight fraction of tungsten carbide (WC), tungsten trioxide (WO₃), and tungsten disulfide (WS₂). Parameters such as the mass attenuation coefficient (MAC), half-value layer (HVL), mean free path (MFP), effective atomic number (Z_eff), and macroscopic effective removal cross-section for fast neutrons (Σ_R) were calculated using the Phy-X/PSD software. EpiXS simulations were conducted for MAC validation. Results and Discussion: Increasing the weight fraction of the additives resulted in higher MAC values, indicating improved radiation shielding. PVDF-xWC showed the highest percentage increase in MAC values. MFP results indicated that PVDF-0.20WC has the lowest values, suggesting superior shielding properties compared to PVDF-0.20WO₃ and PVDF-0.20WS₂. PVDF-0.20WC also exhibited the highest Z_eff values, while PVDF-0.20WS₂ showed a slightly higher increase in Z_eff at energies of 0.662 and 1.333 MeV. PVDF-0.20WC has demonstrated the highest Σ_R value, indicating effective shielding against fast neutrons, while PVDF-0.20WS₂ had the lowest Σ_R value. The Monte Carlo N-Particle Transport version 5 (MCNP5) simulations showed that PVDF-xWC attenuates gamma radiation more than pure PVDF, significantly decreasing the dose equivalent rate. Conclusion: Overall, this research provides insights into the radiation shielding properties of PVDF mixtures, with PVDF-xWC showing the most promising results.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.4B
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• pp.332-345
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• 2011

As weapon systems are evolving into more advanced and complex ones, the role of the software is becoming heavily significant in their developments. Particularly in the war field of today as represented by the network centric warfare(NCW), the reliability of weapon systems is definitely crucial. In this context, it is inevitable to develop software reliably enough to make the weapon systems operate robustly in the combat field. The reliability engineering activities performed to develop software in the domestic area seem to be limited to the software reliability estimations for some projects. To ensure that the target reliability of software be maintained through the system's development period, a more systematic approach to performing software reliability engineering activities are necessary from the beginning of the development period. In this paper, we consider the software reliability in terms of the development of a weapon system as a whole. Thus, from the systems engineering point of view, we analyze the models and methods that are related to software reliability and a variety of associated activities. As a result, a process is developed, which can be called the software reliability engineering process for weapon systems (SREP-WS), The developed SREP-WS can be used in the development of a weapon system to meet a target reliability throughout its life-cycle. Based on the SREP-WS, the software reliability could also be managed quantitatively.

• Korean Journal of Environmental Agriculture
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• v.22 no.2
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• pp.166-171
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• 2003

A total of 498 agricultural reservoirs ranging from $164{\times}10^3\;m^3$ to $253{\times}10^6\;m^3$ in storage volume were investigated from 1990 to 2001 with respect to Chl-${\alpha}$, COD concentration and pollutant loading of BOD, TN, and TP. The lakes and reservoirs could be classified to 4 types using the relationships between the ratio of storage volume per water surface area(ST/WS) and Chl-${\alpha}$ concentration. It is recommended that the improvement of polluted lakes should be performed in the order of integrated consolidation type ${\rightarrow}$ watershed consolidation type ${\rightarrow}$ in-lake consolidation type ${\rightarrow}$ Management type and reservoir should be constructed to be over $5{\sim}6\;m$ in depth(ST/WS ratio) for preventing the eutrophication of agricultural reservoirs. We propose that water quality criteria for agricultural water is changed from less than 8 mg/L to less than 6 mg/L for safety value, $6{\sim}10\;mg/L$ for concern value, and more than 10 mg/L for countermeasure value in COD concentration, respectively.

• Journal of the Korean Society of Marine Environment & Safety
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• v.13 no.1 s.28
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• pp.29-37
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• 2007

The effect of meteorological factors such as air temperature (AT), wind speed (WS), precipitation (Pre) on the variation of water temperature (WT) and salinity (Sal) in the West Sea of Korea for the period 1971 to 2001 was illustrated. As a result of this study, WT-AT, WT-Pre, and Sal-WS had positive correlation, reversely WT-WS, Sal-AT and Sal- Pre had negative correlation. In the surface layer, time lag between atmospheric factors and oceanographic factors was 0 to 4 months, on the other hand in the bottom layer, it was delayed 0 to 4 months compared to the surface. WT was affected by AT in the same year, but Sal was affected by precipitation in the previous year. The variation of WT and Sal was in harmony with change of wind speed.

• YAKHAK HOEJI
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• v.19 no.1
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• pp.16-20
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• 1975

A polyacetylenic compound ws isolated from the subterranean parts of Bupleurum falcatum L. (Umbelliferae) and its structure was elucidated as pentadecadiene-(2, 9)-diyn-(4, 6)-ol(1) acetate.

• Korean Journal of Poultry Science
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• v.34 no.3
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• pp.173-180
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• 2007

This study was conducted to evaluate conjugated linoleic acid (CLA) precursor and produce supplementation on egg production, egg quality and blood immunological parameters in laying hens. The total of 252 (32-wk) Hy-line brown commercial hens were used for 5 weeks. Dietary treatments included 1) CON (basal diet + oat 1% + soybean oil 1%), 2) WOS (basal diet + whey 0.5% + oat 0.5% + soybean oil 1%), 3) WS (basal diet+ whey 1% + soybean oil 1%), 4) WOCLA (basal diet + whey 0.5% + oat 0.5% + CLA produce 1%), 5) WCLA (basal diet + whey 1% + CLA produce 1%) and 6) FOCLA (basal diet + Fish oil 0.5% + oat 1% + CLA produce 0.5%). For 4 weeks egg shell thickness was higher in WOS and FOCLA treatments than WOCLA and WCLA treatments (P<0.05). Egg weight was significantly increased (P<0.05) in WOS and FOCLA treatments compared to WS and WCLA treatments for 4 weeks. From 4 to 5 weeks yolk high, yolk color and haugh unit were significantly higher in FOCLA treatment than CON treatment (P<0.05). IgG concentration of blood was increased in WOS and FOCLA treatments compared to CON, WS and WOCLA treatments(P<0.05). In conclusion, fish oil, CLA produce and oat supplementation in laying hens diet improve egg shell thickness, yolk high, yolk color and haugh unit, also, CLA precursor supplementaion in laying hens diet improve IgG concentration of blood higher than CON treatment.

• Atmosphere
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• v.23 no.4
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• pp.443-452
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• 2013

The original Fog Stability Index (FSI) is formulated as FSI=$2(T-T_d)+2(T-T_{850})+WS_{850}$, where $T-T_d$ is dew point deficit (temperature-dew point temperature), $T-T_{850}$ is atmospheric stability measure (temperature-temperature at 850 hPa altitude) and $WS_{850}$ is wind speed at 850 hPa altitude. As a way to improve fog prediction at Incheon International Airport (IIA), we develop the modified FSI for IIA, using the meteorological data at IIA for two years from June 2011 to May 2013, the first one year for development and the second one year for validation. The relative contribution of the three parameters of the modified FSI is 9: 1: 0, indicating that $WS_{850}$ is found to be a non-contributing factor for fog formation at IIA. The critical success index (CSI) of the modified FSI is 0.68. Further development is made to consider the fact that fogs at IIA are highly influenced by advection of moisture from the Yellow Sea. One added parameter after statistical evaluation of the several candidate parameters is the dew point deficit at a buoy over the Yellow Sea. The relative contribution of the four parameters (including the new one) of the newly developed FSI is 10: 2: 0.5: 6.4. The CSI of the new FSI is 0.50. Since the developmental period of one year is too short, the FSI should be refined more as the data are accumulated more.