• Journal of the Korean Society of Marine Environment & Safety
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• v.18 no.3
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• pp.199-205
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• 2012

In this study, wave transformation by damping due to the permeable bed of finite depth is investigated. The relationship between wave damping rate and relative water depth are presented. The damping rate is used in the eigenfunction expansion method to calculate the wave dissipation over the permeable bed. For a permeable shoal, the eigenfunction expansion model result is compared with that of the integral equation method to show good agreement. The model is also used to examine the wave reflection over the permeable planar slope of various frequency. It has been found that in general relatively short waves are more influenced by the permeability of the permeable seabed than relatively long waves unless the water depth is so large that the influence of permeable bed on surface water waves disappears.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.39 no.4
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• pp.61-67
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• 2007

Paper sludges collected from three different paper mills were physico-chemically analyzed in order to use them as raw materials for making bed soils and seedling pots. The sludge from a fine paper mill contained lots of inorganic pigment particles used for coating, as those from a newsprint mill and a tissue mill had not. It was clearly through XRD analysis confirmed that all sludges included calcium carbonate. The paper sludge from the tissue mill contained the greatest amount of particles, which would contribute to water absorption and nutrient storage. The sludge from the fine paper mill had the highest density due to many inorganic elements. While the ash content and the total nitrogen content were the highest in the sludge from the fine paper mill, the C/N ratio was the lowest in the fine paper mill sludge. All sludges seemed to have insufficient contents of potassium. The sludges from the newsprint mill and the tissue mill showed more silicon contents than that from the fine paper mill. It was concluded that the sludge from the fine paper mill would be able to be the most efficient raw materials for making bed soils and seedling pots and the other two sludges would be more efficient for intensive culture for crops such as rice and grain with additional supplement of nitrogen and other nutrients.

• KEPCO Journal on Electric Power and Energy
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• v.1 no.1
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• pp.115-120
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• 2015

$K_2CO_3$-based dry regenerable sorbents were prepared by spray-drying techniques to improve mass produced $K_2CO_3-Al_2O_3$ sorbents (KEP-CO2P, hereafter), and then tested for their $CO_2$ sorption capacity by a $2,000Nm^3/h$ (0.5 MWe) $CO_2$ capture pilot plant built for Unit 3 of the Hadong thermal power station in 2010. Each of the sample sorbents contained 35 wt.% $K_2CO_3$ as the active materials with various support materials such as $TiO_2$, MgO, Zeolite 13X, $Al_2O_3$, $SiO_2$ and hydrotalcite (HTC). Their physical properties and reactivity were tested to evaluate their applicability to a fluidized-bed or fast transport-bed $CO_2$ capture process. The $CO_2$ sorption capacity and percentage utilization of $K_2CO_3$-MgO based sorbent, Sorb-KM2, was $8.6g-CO_2/100g$-sorbents and 90%, respectively, along with good mechanical strength for fluidized-bed application. Sorbs-KM2 and KT were almost completely regenerated at $140^{\circ}C$. No degradation of Sorb-KM by $SO_2$ added as a pollutant in flue gas was observed during a cycle test.

• Fire Science and Engineering
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• v.23 no.6
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• pp.10-15
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• 2009

Flame height calculation in a forest fire is a crucial part of predicting horizontal or vertical flame spread flared by radiation heat transfer. Flame height, which is one of the flame characteristics, can be estimated by the average height of luminous flame. This research relied on flame height observation test on P. densiflora surface fuel bed, which are surface combustibles in a forest, and calorimeter to measure Heat Release Rate, thus produced $H_f=0.027(\dot{Q'})^{2/3}$, flame height calculation equation for surface fuel. The research did not take into consideration such conditions as external velocity, slope and other variables that could affect flame height. According to comparison among experiment results, calculation results of the above formula and those of existing Heskestad formula (1998), it was found that standard error in fallen pine needles between experimental results and calculation results of the above formula amounts to 0.08, whereas standard error in same plant between experimental results and calculation results of existing Heskestad formula amounts to 0.23.

• Journal of Korean Society of Water and Wastewater
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• v.9 no.2
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• pp.97-107
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• 1995

Today a conventional water treatment system has many problems. The ozone/GAC process, sometimes termed Biological Activated Carbon(BAC), appeared to be effective for the removal of soluble organic matters in the drinking water. The water quality of Nak-dong river in Pusan, generally shows BDOC 30-40% and NBDOC 60-70%. The pilot plant installed at the Duk-san water works that was been largest treatability(1,650,000ton/day) in Pusan. A experimental water in the pilot plant made use of the water after sand-filteration. Following results are drawn from this study. Initial adsorption velocity($DOC/DOC_o/T$) in the pure adsorption of GAG had a 0.0225, it's velocity changed to 0.006 after ozone added and the optimum ozone dose ranged of $1.4-2.0mgO_3/L$. A experimental water in the pilot plant composed with humic material(78%). Humic material composed with humic acid(20%) and fulvic acid(56%), and it's rate changed to 18 and 50% respectively after ozone added. DOC constantly decreased in the EBCTs and removal efficieny in the 15min of EBCT was 45-50%. It showed the largest removal rate of BDOC in the EBCT 5 and among the season, characteristics of removal varied. The HPC distributed over $10^6-10^7CFU/cm^3$ in the bed depth and among the season, distribution of HPC were differential.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.2
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• pp.145-149
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• 2001

This study was performed to evaluate the growth and nodulation characters of hypernodulating soy-bean mutant, SS2-2, and to know the growth and yield performance of the mutant in infertile soil. Soil fertility was adjusted by mixing the different ratios of soil components including clay, river sand, and horticultural bed, which resulted in fertile and infertile soil. Dry weight, nitrogen concentration, and leaf nitrate reductase of each plant were measured around V6 stage (47 days after planting) and around R3 stage (82 days after planting). There were significant effects of soil fertility and soybean genotype on the total dry weights including root, nodule, stem, leaf, and pod dry weight at V6 and R3 stages. Total dry weight of hypernodulating mutant, SS2-2, was clearly less than that of its wild type, Sinpaldalkong 2. However, nodule development on the roots of SS2-2 was much greater than that of Sinpaldalkong 2, regardless of soil fertility. Though SS2-2 was smaller in plant size than Sinpaldalkong 2, genotypic difference in total nitrogen content was not significant at both V6 and R3 stages because SS2-2 fixed more nitrogen biologically than its wild type in the root nodule. The SS2-2 mutant showed lower plant yield in both infertile and fertile soil. The SS2-2 contained more crude seed protein than Sinpaldalkong 2, and was characterized with reduced top and root growth.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.2
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• pp.272-279
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• 2012

In order to effectively treat livestock wastewater in constructed wetlands by natural purification method, removal velocities of pollutants under different injection methods in constructed wetlands were investigated. The removal velocities of chemical oxygen demand (COD), suspended solid (SS), T-N and T-P by continuous injection method were slightly rapid than those by intermittent injection method in full-scale livestock wastewater treatment plant. The removal velocity (K; $day^{-1}$) of COD by continuous injection method was $0.38\;d^{-1}$ for $1^{st}$ bed, $0.13\;d^{-1}$ for $2^{nd}$ bed, $0.17\;d^{-1}$ for $3^{rd}$ bed, $0.05\;d^{-1}$ for $4^{th}$ bed and $0.17\;d^{-1}$ for $5^{th}$ bed. The removal velocities (K; $day^{-1}$) of COD in $1^{st}$, $2^{nd}$, $3^{rd}$, $4^{th}$ and $5^{th}$ beds by intermittent injection method were $0.210\;d^{-1}$, $0.086\;d^{-1}$, $0.222\;d^{-1}$, $0.053\;d^{-1}$ and $0.137\;d^{-1}$, respectively. The removal velocity (K; $day^{-1}$) of SS by continuous injection method was $0.750\;d^{-1}$ for $1^{st}$ bed, $0.108\;d^{-1}$ for $2^{nd}$ bed, $0.120\;d^{-1}$ for $3^{rd}$ bed, $0.086\;d^{-1}$ for $4^{th}$ bed and $0.292\;d^{-1}$ for $5^{th}$ bed. The removal velocities (K; $day^{-1}$) of SS in $1^{st}$, $2^{nd}$, $3^{rd}$, $4^{th}$ and $5^{th}$ beds by intermittent injection method were $0.485\;d^{-1}$, $0.056\;d^{-1}$, $0.174\;d^{-1}$, $0.081\;d^{-1}$ and $0.227\;d^{-1}$, respectively. The removal velocity (K; $day^{-1}$) of T-N by continuous injection method was $0.361\;d^{-1}$ for $1^{st}$ bed, $0.121\;d^{-1}$ for $2^{nd}$ bed, $109\;d^{-1}$ for $3^{rd}$ bed, $0.047\;d^{-1}$ for $4^{th}$ bed and $0.155\;d^{-1}$ for $5^{th}$ bed. The removal velocities (K; $day^{-1}$) of T-N in $1^{st}$, $2^{nd}$, $3^{rd}$, $4^{th}$ and $5^{th}$ beds by intermittent injection method were $0.235\;d^{-1}$, $0.071\;d^{-1}$, $0.171\;d^{-1}$, $0.058\;d^{-1}$ and $0.126\;d^{-1}$, respectively. The removal velocity (K; $day^{-1}$) of T-P by continuous injection method was $0.803\;d^{-1}$ for $1^{st}$ bed, $0.084\;d^{-1}$ for $2^{nd}$ bed, $0.076\;d^{-1}$ for $3^{rd}$ bed, $0.118\;d^{-1}$ for $4^{th}$ bed and $0.301\;d^{-1}$ for $5^{th}$ bed. The removal velocities (K; $day^{-1}$) of T-P in $1^{st}$, $2^{nd}$, $3^{rd}$, $4^{th}$ and $5^{th}$ beds by intermittent injection method were $0.572\;d^{-1}$, $0.049\;d^{-1}$, $0.090\;d^{-1}$, $0.112\;d^{-1}$ and $0.222\;d^{-1}$, respectively.

• Resources Recycling
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• v.20 no.1
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• pp.54-60
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• 2011

The spherical artificial aggregates (AAs) with a diameter of 8 mm, which contains fly ashes discharged from the fluidized bed combustion in a thermal power plant and clay were manufactured by direct sintering method at $1050{\sim}1250^{\circ}C$ for 10 minutes. The effect of fly ash contents on the bloating phenomenon in the AAs was analyzed. The AAs containing fly ash of the amount under 50 wt% showed the black-coring and bloating phenomena. The AAs containing fly ash of the amount over 5Owt%, however, the specific gravity was increased and the color of specimens fully changed to black. These color change phenomena were caused from the formation of FeO by the reduction reaction of almost $Fe_2O_3$ component by the excessive reducing atmosphere formed simultaneously with the rapid emission of the gases generated from the high contents of unburned carbon of with increasing the added fly ash amount. Specific gravity was decreased as fly ash contents increased in the case of sintering at the same temperature condition. Water absorption of all specimens except of the specimens containing 10 wt% fly ashes decreased with increasing sintering temperature. These were because a liquid phase was formed as the increasing the sintering temperature. In the case of the specimens manufactured in this study containing fly ashes discharged from the fluidized bed combustor in a the thermal power plant and 10~90 wt% of clay, the specific gravity was 0.9~1.8 and the water absorptivity was 8~60%, therefore it is considered that those results can be applied to the light or heavy aggregates.

• Korean Journal of Plant Resources
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• v.9 no.1
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• pp.1-9
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• 1996

The effects of multipore spawn inoculation of Lentinus edodes on the mycelial growth stage and on the quantitative and qualitative yields of fruit-bodies for 5 years were investigated at natural environmental conditions. The spawn inoculation quantity did not affect the mycelial rooting at a range of 3.0kg-6.0kg per $m^3$ of bed-logs while the increase of spawn quantity by multipore inoculation increased the mycelial growth and the inner erosion of bed-logs, resulting in the increased yields of total fruit-bodies of L. edodes per $m^3$ of bed-logs for 5 years but resulting in the shortened major production period of fruit-bodies to the the first three years. Major production of fruit-bodies occurred during May-June and August-September, which was not affected by the spawn inoculation quantity. No significant differences in dry weight of a fruit-body were observed as increasing the spawn quantity by multipore inoculation; however the heaviest dry weight of a fruit-body was 1.63g at the spawn inoculation of 4.0kg per $m^3$/TEX> of bed-logs.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.9
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• pp.917-922
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• 2005

The wastewaters from textile and dyeing industries are difficult to treat due to its high pH, temperature, color intensity and non-biodegradable organic contents. This study investigated the removal of recalcitrant organics in a dyeing wastewater by using a packed bed reactor (PBR) that contained cell-immobilized pellets. The feed, obtained from an effluent of a biological treatment plant, had $SCOD_{Cr}$ of 330 mg/L and $SBOD_5$ of 20 mg/L on average. In immobilizing the cells to a Polyethylene Glycol(PEG) based medium, activated sludges from either a sewage treatment plant or an industrial wastewater treatment plant were used. When the empty bed contact time (EBCT) was above 8 hrs in the PBR, the $COD_{Cr}$ removal efficiency was over 50% and the $COD_{Mn}$ concentration was 72 mg/L or lower on average, which was substantially lower than the discharge standard of 90 mg/L. The results indicated that the optimum EBCT in the PBR was 8 hrs. The PBR with cell-immobilized pellets was effective as an advanced treatment process after an activated sludge process for treating dyeing wastewaters.