• Journal of Mushroom
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• v.13 no.3
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• pp.250-255
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• 2015

In this study spent mushroom substrate has ingredient raising rice bed soil. spent mushroom substrates are organic content is 60.72% were nitrogen - phosphoric acid - potassium is 1.39 - 0.89 - 0.81% of the chemical characteristics determine. Post-harvested mushroom substrates of the stabilization process, the temperature of the 20 days time progress in the pH of the rise and fall of temperature down were germination index also 77, as identified, Spent mushroom substrate bed soil for raising rice Ingredient to take advantage of the 20 days or more stabilization process needed to be investigated. Rice seed germination characteristic is in the common bed soil for raising rice ingredients manufactured control group and the comparison in spent mushroom substrate is 10% or less of a mixed experimental population of the germination rate is 82% was more than average days to germination and germination energy, even a statistical significant difference is or control group than good level was ok. Growth initial also spent mushroom substrate is 10% or less of a mixed experimental population of shoot dry matter (top) and grave less than control group higher as confirmed spent mushroom substrates are bed soil for raising rice ingredients are likely to take advantage of the high, as was the judge.

• Plant Journal
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• v.6 no.2
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• pp.70-77
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• 2010

This study investigated the characteristics of co-combustion of mixed anthracite (domestic and Vietnam) and bituminous coal (Sonoma, Australia) at circulating fluidized bed boiler in Donghae thermal power plant when mixing ratio of bituminous coal is variable. Co-combustion of bituminous coal contributes to improvement in general combustion characteristics such as moderately retaining temperature of furnace and recycle loop, reducing unburned carbon powder, and reducing discharge concentration of NOx and limestone supply owing to improvement in anthracite combustibility as the mixing ratio was increased. However, bed materials were needed to be added externally when the mixing ratio exceeded 40% because of reduction in generating bed materials based on reduction in ash production. When co-combustion was conducted in the section of 40 to 60% in the mixing ratio while the supplied particles of bituminous coal was increased from 6 mm to 10 mm, continuous operation was shown to be possible with upper differential pressure of 100 mmH2O (0.98 kPa) and more without addition of bed materials for the co-combustion of mixed anthracite and bituminous coal (to 50% or less of the ratio) and that of domestic coal and bituminous coal (to 60% of the ratio).

• Research in Plant Disease
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• v.24 no.4
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• pp.257-264
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• 2018

Hydroponic strawberry culture system is increasing annually. Most of strawberry farmers use mulched bed in hydroponic culture and strawberry plants were transplanted in early September. After transplanting, Fusarium wilt caused by Fusarium oxysporum f. sp. fragariae and twospotted spider mite (TSSM), Tetranychus urticae, can increase their occurrence under high temperature condition. Therefore, we conducted for comparison occurrence of Fusarium wilt and TSSM on mulched with green polyethylene film and non-mulched bed. Occurrence of Fusarium wilt on mulched bed was started from early October and more increase than non-mulched bed. Damage rate of TSSM on mulched bed was shown higher than non-mulched bed. Temperature of substrate in mulched bed increased than non-mulched bed, but relative humidity near plants was decreased. As a result, use of non-mulched bed should be effective for reducing of Fusarium wilt and TSSM on strawberry plants.

• Proceedings of the KIEE Conference
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• 1998.07b
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• pp.722-724
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• 1998

One of the major concerns of our time is the need to use energy economically and rationally while at the same time, protecting the environment. Circulating Fluidized Bed(CFB) Boilers represent a proven, very attractive clean coal technology, with the added advantage of an unusual fuel flexibility CFB boiler is the best available compromise between cost and environment for fossil fuel power plant. This paper briefly describes CFB process and 200MW CFB boiler for Tonghae power plant. Also, discussed are differences between the control process of fluidized bed and conventional boilers, and applied control process for Tonghae power plant.

• Journal of Ocean Engineering and Technology
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• v.17 no.2
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• pp.8-13
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• 2003

Soil, ground water, and sea bed are exposed to a continuous accumulation of polluted materials, causing serious environmental damage. It has been reported that such pollution causes a massive mortality of fish stock in rivers due to the resuspension of toxic chemicals, occurring during strong wind conditions. Therefore, it becomes apparent that there is an immediate demand for the restoration treatment of polluted river bed (or sea bed) sediment layers. Pollution levels of major rivers and ports, such as Paldang, Kyungan rivers, and Masan port, are becoming of great public concern, and are posing a serious environmental threat. In particular, the pollution of the Shi-hwa river has become a nation wide issue for the last few years. In spite of such public concern, the pollution levels of such rivers or ports are worsening everyday. In this study, an environmentally sound engineering package is introduced that helps to restore the polluted river bed or sea bed sediments. This engineering package consists of a suction facility, followed by a series of mechanical, chemical, and biological treatment units. The suction facility is designed to minimize secondary pollution that occurs from the resuspension of toxic materials during suction. The sea bed cleaning engineering package is designed to be installed on the top of a floating barge. Such a combination of environmental plant and shipbuilding technology provides a cost-effective solution, minimizing the transportation between suction and treatment facilities.

• Journal of Biosystems Engineering
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• v.37 no.3
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• pp.155-165
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• 2012

This study was performed to offer the data for design of the seedling bed transfer equipment to make the automation of working process in a plant factory. The seedling bed transfer equipment pushing the seedling bed with bearing wheels on the rail for interconnecting each working process by a pneumatic cylinder was made and examined. The examined transfer force to push the seedling bed with a weight of 178.9 N by the pneumatic cylinder with length of 60 cm and section area of 5 $cm^2$ was measured by experiments. The examined transfer forces was compared with theoretical ones calculated by the theoretical formula derived from dynamic system analysis according to the number of the seedling bed and pushing speed of the pneumatic cylinder head at no load. The transfer function of the equipment with the input variable as the pushing speed $V_{h0}$(m/s) and the output variable as the transfer force f(t)(N) was represented as $F(s)=(V_{h0}/k)(s+B/M)/(s(s^2+Bs/M+1/(kM))$ where M(kg), k(m/N) and B(Ns/m) are the mass of the bed, the compression coefficient of the pneumatic cylinder and the dynamic friction coefficient between the seedling bed and the rail, respectively. The examined transfer force curves and the theoretical ones were represented similar wave forms as to use the theoretical formular to design the device for the seedling bed transfer. The condition of no vibration of the transfer force curve was $kB^2>4M$. The condition of transferring the bed by the repeatable impact and vibration force according to difference of transfer distance of the pneumatic cylinder head from that of the bed was as $Ce^{-\frac{3{\pi}D}{2\omega}}<-1$, where ${\omega}=\sqrt{\frac{1}{kM}-\frac{B^2}{4M^2}}$, $C=\{\frac{\frac{B}{2M}-\frac{1}{kB}}{\omega}\}$, $D=\frac{B}{2M}$. The examined mean peak transfer force represented 4 times of the stead state transfer force. Therefore it seemed that the transfer force of the pneumatic cylinder required for design of the push device was 4Bv where v is the pushing speed.

• Journal of Korean Society of Water and Wastewater
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• v.26 no.3
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• pp.409-421
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• 2012

Ethanolamine (ETA) is mainly used to prevent corrosion of pipe in secondary cooling system of nuclear power plant. Condensed ETA in wastewater could increase COD and T-N when it was emitted to natural water system. Compared to conventional treatments, electrochemical oxidation process using packed bed bipolar electrodes was adopted to treat COD and T-N. According to arrangement of feeder electrode, single packed bed bipolar electrode reactor and multi-paired packed bed bipolar reactor were developed and conventional zero-valent iron (ZVI) was selected as conducting bipolar electrode. Bipolar electrodes were coordinated three-dimensionally in the reactor. The experimental results showed that COD and T-N was little removed in unit system at different pH condition (pH 8 and 11) on 100V. However, in multi-paired system that applied 600V, COD was eliminated 80.85% (anode-cathode-anode, A-C-A) and 85.11% (cathode-anode-cathode, C-A-C), respectively. T-N was also removed 96.88% (A-C-A) and 90.63% (C-A-C), simultaneously. Current efficiency was estimated both single and multi-paired system. At unit bipolar packed bed reactor, current efficiency was almost zero, however in multi-paired system, current efficiency was 300~500% at A-C-A and 250~350% at C-A-C. Current efficiency was over 100% hence it was confirmed that this system is more effective than conventional electrochemical oxidation system.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2002.11b
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• pp.8-8
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• 2002

• KOREAN JOURNAL OF CROP SCIENCE
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• v.13
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• pp.77-81
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• 1973

The experiment was carried out to make clear the root characters and relationships among some quantitative characters of soybeans. The results obtained are summarized as follows: 1. Stem diameter was shown the greater growing in thickness after one month from sowing than the earlier stage, and the greater growing was shown in fertile bed soil than in sand soil. 2. The elongation of plant top in soybean plant was also shown the greater rate in bed soil than in sand soil 3. The length of plant root was longer than the length of plant top in the earlier stage of growing, and the length of root was much greater in sand soil than in fertile bed soil. 4. Weight of plant top was shown more in bed soil than in sand soil, but this tendency was shown more greater rate in the length of plant top than in weight of plant top. 5. Weight of root was more compared with weight of plant top in the earlier stage of growth, and also more greater rate was shown in sand soil than in fertile bed soil. 6. Highly significant correlations were shown among five quantitative characters, namely stem diameter, length of top, weight of top, length of root and weight of root, etc.

• Membrane and Water Treatment
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• v.11 no.4
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• pp.247-255
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• 2020

Sand filter is a key unit process for particle removal in water purification treatments. Its long-standing use is due to on-site customized retrofit. Proper selection of filter media is one of the retrofit approaches to improve filter performance. This study described a series of controlled laboratory column tests and examined the effects of media property on filtration and backwash. When sand media of 0.51 mm in effective size was replaced by sand of 0.60 mm, the filter run increased up to 5 times in the given bed depth. The change of media property required an increase of backwash rate by 0.05 m/min to satisfy the requirement of bed expansion, more than 20%. When the anthracite was changed with lower effective size and uniformity coefficient, correlation with sand in the filter bed could be satisfied within the permissible error between media and bulk characteristics. Besides, this selection resulted in a well-stratified configuration of media layers after bed expansion. The column study showed that the correlation of property between the dual media had a significant effect on the filter productivity and backwash interval.