• 한국환경과학회지
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• 제25권3호
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• pp.337-343
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• 2016

The present study aimed to determine the influence of various root restriction media on seedling quality and early growth of strawberry after transplanting. The root activity of the seedlings, measured 20 days after fixation, was considerably higher (0.096, 0.090, and $0.063mg{\cdot}g^{-1}{\cdot}h^{-1}$ at 420, 450, and 480 nm, respectively) in expanded rice hull (ERH) treatment than in the sandy loam and loamy sand treatments. The volumetric water content (VWC) of the root media tested across 3 irrigation regimes (15 d, 30 d, 45 d) in the nursery field was highest in sandy loam (65.0-66.8%), followed by 59.4-61.3% in loamy sand and 38.6-45.3% in ERH. When growth parameters of runner plantlets were compared, ERH treatment was found to result in the highest crown thickness and fresh weights of root and above-ground parts. This had a favorable influence on above-ground tissue growth after transplanting to plastic house soil. As mentioned above, ERH treatment resulted in the highest seedling quality and early growth after transplanting. The results of this study would serve as useful on-site data for the production of high-quality strawberry seedlings.

• 열처리공학회지
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• 제23권5호
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• pp.249-256
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• 2010

Water jet impingement cooling has been widely used in a various engineering applications; especially in cooling of hot steel plate of steelmaking processes and heat treatment in hot metals as an effective method of removing high heat flux. The effects of cooling water temperature on water jet impingement cooling are primarily investigated for hot steel plate cooling applications in this study. The local heat flux measurements are introduced by a novel experimental technique that has a function of high-temperature heat flux gauge in which test block assemblies are used to measure the heat flux distribution during water jet impingement cooling. The experiments are performed at fixed flow rate and fixed nozzle-to-target spacing. The results show that effects of cooling water temperature on the characteristics of jet impingement heat transfer are presented for five different water temperatures ranged from 5 to $45^{\circ}C$. The local heat flux curves and heat transfer coefficients are also provided with respect to different boiling regimes.

• Asian-Australasian Journal of Animal Sciences
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• 제24권8호
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• pp.1148-1156
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• 2011

Compensatory growth of juvenile olive flounder Paralichthys olivaceus fed different diets with different feeding regime was compared. Four hundred fifty fish (twenty five fish per tank) were randomly distributed into 18 of 180 L flow-through tanks. Six treatments were prepared: fish were hand-fed with the control (C) diet to satiation twice a day, six days a week, for 8 weeks (C-8W treatment); and other groups of fish were starved for 2 weeks and then fed with the C, high protein (HP), high carbohydrate (HC), high lipid (HL), and combined protein, carbohydrate and lipid (CPCL) diets to satiation twice a day, six days a week, for 6 weeks, referred to as C-6W, HP-6W, HC-6W, HL-6W, and CPCL-6W treatments, respectively. Final body weight of fish in HP-6W treatment was higher than that of fish in C-6W, but not different from that of fish in C-8W, HC-6W, HL-6W and CPCL-6W treatments. Specific growth rate of fish in HP-6W treatment was higher than that of fish in all other treatments except for fish in CPCL-6W treatment. Feeding rate of fish in C-8W treatment was higher than that of fish in HP-6W, HC-6W, HL-6W and CPCL-6W treatments, but not different from that of fish in C-6W treatment. In addition, feeding rate of fish in C-6W treatment was higher than that of fish in HP-6W, HL-6W and CPCL-6W treatments. Feed and protein efficiency ratios of fish in HP-6W, HC-6W, HL-6W and CPCL-6W treatments were higher than those of fish in C-6W treatment. None of moisture, crude protein and ash content of the whole body of fish excluding the liver was different among treatments. Dietary supplementation of protein, carbohydrate, lipid and their combination could improve compensatory growth of fish when fish were fed for 6 weeks after 2-week feed deprivation; especially, supplementation of dietary protein was the most effective to improve compensatory growth of fish.

• Asian-Australasian Journal of Animal Sciences
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• 제5권4호
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• pp.659-664
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• 1992

Twelve day old Pabna zebu calves of similar weights were assigned at random to 3 different calf starter-rations namely $T_0$, $T_1$ and $T_2$ to determine the effect of feeding regimes and growth pattern of calves upto 3 months of age. Calves allowed to intake starter 0.5 percent of body weight from 2nd week on to 7th weeks of age, while starter at 1 percent of body weight was allowed later on upto 13th weeks of age. Calves started to intake green grass after 2nd to 3rd weeks and average intake per day was limited to 1 kg upto the end of experiment, while calves started to take rice straw ad libitum after 6th weeks of age. Colostrum feeding was offered ad libitum and in addition calves suckled their dam's milk shortly before and after milking usually in the morning and evening. Growth of calves in different treatment groups was found statistically insignificant. The mean growth rate per head per day ranged from 196.43-375.0 g for $T_0$ group, 185.72-360.72 g for $T_1$ group and 180.1-385.72 g for $T_2$ group respectively between 1st to 7th weeks of age while the growth rate ranged from 309.53-328.57 g for $T_0$, 304.29-342.86 g for $T_1$ and 304.77-333.30 g for $T_2$ groups respectively from 9th weeks on to the end of the experiment.

• Ocean Systems Engineering
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• 제4권3호
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• pp.185-200
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• 2014

The objective of the present simulations is to evaluate the applicability of the standard $k-{\varepsilon}$ turbulence model in engineering practice in the subcritical to supercritical flow regimes. Two-dimensional numerical simulations of flow around a circular cylinder at $Re=1{\times}10^5$, $5{\times}10^5$ and $1{\times}10^6$, had been performed using Unsteady Reynolds-Averaged Navier Stokes (URANS) equations with the standard $k-{\varepsilon}$ turbulence model. Solution verification had been studied by evaluating grid and time step size convergence. For each Reynolds number, several meshes with different grid and time step size resolutions were chosen to calculate the hydrodynamic quantities such as the time-averaged drag coefficient, root-mean square value of lift coefficient, Strouhal number, the coefficient of pressure on the downstream point of the cylinder, the separation angle. By comparing the values of these quantities of adjacent grid or time step size resolutions, convergence study has been performed. Solution validation is obtained by comparing the converged results with published numerical and experimental data. The deviations of the values of present simulated quantities from those corresponding experimental data become smaller as Reynolds numbers increases from $1{\times}10^5$ to $1{\times}10^6$. This may show that the standard $k-{\varepsilon}$ model with enhanced wall treatment appears to be applicable for higher Reynolds number turbulence flow.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2019년도 추계학술대회
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• pp.44-44
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• 2019

Spring sowing of ginseng seeds often results in failure of seedling establishment. Storage condition during winter, sowing time, and seed treatment might effect on germination. Here we tested effects of temperature regimes of seed storage on spring sowing. Dehisced wet or dry ginseng seeds were stored at $2^{\circ}C$, $-2^{\circ}C$, $-3.5^{\circ}C$, or alternating temperature: at $2^{\circ}C$ until December, $-3.5^{\circ}C$ in January, and $2^{\circ}C$ in February, and sowed in March. In overall, emergence rate was dependent on storage temperature, and $-3.5^{\circ}C$ resulted poorest emergence than other conditions. Storage of wet seeds in alternating temperature resulted highest emergence rate. Seed dry also affected on emergence rate, while it was dependent on the storage temperature. In terms of growth, storage at $2^{\circ}C$ as wet seed resulted highest growth, and dried seeds resulted poorer growth than wet seeds. As a modification of alternating temperature, seeds were stored at $2^{\circ}C$ at first, then transferred to $-3.5^{\circ}C$ at Nov 30, Dec 20, and Jan 10, each. When transfer date was delayed, emergence rate was increased. We suggest that seed storage temperature for ginseng should not be decreased below $-2^{\circ}C$, and alternative temperature regime for successful spring sowing could be useful.

• Journal of the Korean Wood Science and Technology
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• 제51권2호
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• pp.109-132
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• 2023

The objective of this study was to reveal the impact of thinning and pruning regimes on the physical and mechanical properties of clonal teak wood planted in Java. In this study, a 15-year-old clonal teak plantation was carried out and the obtained data were evaluated with analysis of variance (ANOVA). The results showed that different thinning intensities had a significant impact on the alteration of heartwood volume development (F = 25.63; p < 0.0001). Meanwhile, the impact of different thinning treatments in several physical properties depends on the pruning treatment levels [moisture content (F= 12.18, p < 0.0001); tangential shrinkage (F = 15.60, p < 0.0001); T/R ratio (F = 7.17, p < 0.0001); and volumetric shrinkage (F = 10.81, p < 0.0001)]. However, different thinning intensities had no significant impact on wood basic density alteration (F = 0.72, p = 0.486), while pruning intensities affect the differences between radial (F = 3.52, p = 0.030) and volumetric shrinkage (F = 3.13, p = 0.044). In mechanical properties, thinning intensity levels did not promote any significant differences [modulus of elasticity (F = 1.41, p = 0.248); modulus of rupture (F = 0.94, p = 0.392); compressive strength parallel to grain (F = 0.21, p = 0.813); and compressive strength perpendicular to the grain (F = 0.41, p = 0.669)]. Meanwhile, different pruning treatments and combination treatments were not significantly altered all mechanical properties. These results indicated that the thinning and pruning regimes can enhance the mechanical properties without having a serious alteration in the physical properties of clonal teak wood.

• 환경영향평가
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• 제8권2호
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• pp.83-93
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• 1999

ASPEN PLUS, a steady-state simulator, was used in this study for predicting emissions of VOCs and tracing the fate of all compounds in biodegradation processes. Mathematical models for the processes such as volatilization, reaction and clarification were adopted from literatures. Unlike most previous simulations that various pollutants were considered as a single component, COD or BOD, four components of water, biomass, VOCs and COD were included in this simulation. Sensitivity analysis of several physical parameters on the performance of the WWTP was conducted. Model predictions of VOCs emissions agreed well with the plant data. The simulator could provide design conditions for a future WWTP as well as monitoring/control regimes to an existing WWTP.

• East Asian Economic Review
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• 제20권1호
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• pp.3-35
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• 2016

This paper analyses the new discipline on state-owned enterprises contained in the recently concluded Trans Pacific Partnership Agreement, and evaluates various factors that influenced the shaping of its specific rules. The new discipline consolidates and strengthens related provisions in current trade regimes, reflects various aspects of trade disputes between China and the US, and adopts, as its general underlying rationale, the principle of competitive neutrality. The new discipline contains elements that may challenge the multilateral trade regime, and may serve as a role model in regulating state-owned enterprises, including subsidies in services trade in other on-going trade negotiations. The new regime makes us think hard about fundamental issues regarding enforcement of competition policy against state-owned enterprises, treatment of non-market economies, and how to deal with effects of subsidies in international trade, bringing competition issues back on the trade agenda.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2006년도 추계 학술대회논문집
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• pp.106-109
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• 2006

A large eddy simulation with explicit filters on unstructured mesh is presented. Two explicit filters are adopted for reducing the aliasing error of the nonlinear convective term and measuring the level of subgrid scale velocity fluctuation, respectively. The developed subgrid scale model is basically eddy viscosity model which depends on the explicitly filtered fields and needs no additional ad hoc wall treatment such as van Driest damping function. As a validation problem, the flows around a sphere at several Reynolds numbers, including laminar and turbulent regimes, are calculated and compared to experimental data and numerical results in the literature.