• Journal of Bio-Environment Control
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• v.16 no.4
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• pp.395-406
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• 2007

The twenty seven wrap-up vegetables (13 Compositae, 14 Brassicaceae) and seven herbs (6 Labiatae, 1 Umbelliferae) were cultivated with a deep flow technique (DFT) hydroponic beds and treated with 3 levels of nutrient solution concentrations of 1.2, 2.4, and $3.6dS{\cdot}m^{-1}$ in summer and autumn season. The pH and electrical conductivity (EC) change of nutrient solution, fresh weight, and mineral contents of plants were investigated. The pH was maintained lower in high electrical conductivity (EC) treatment and in summer than autumn. EC of nutrient solution in EC $3.6dS{\cdot}m^{-1}$ treatment increased up to $4.8dS{\cdot}m^{-1}$ during the growing period in summer season. The growth of tested plants showed high variations by plant species and nutrient solution concentrations. The coefficient variation (CV) of the shoot fresh weight of plants was higher in summer than autumn. The growth of Compostiae and herbs was better at EC $1.2dS{\cdot}m^{-1}$, and 14 Brassicaceae was better at EC $2.4dS{\cdot}m^{-1}$ in summer. In autumn, the growth was better at EC $2.4dS{\cdot}m^{-1}$ in all plants except kale 'TBC F1' and red rape 'honchaetae'. In mineral contents, total nitrogen and potassium were higher in autumn than summer. Total nitrogen, potassium, calcium, magnesium were higher in Brassicaceae than others. Iron and manganese, however, were higher in Compositae. As the results, this study suggests that mixed planting of 27 wrap-up vegetables and 7 herbs in DFT hydroponics in two seasons was possible and EC $1.2dS{\cdot}m^{-1}$ in summer and EC $2.4dS{\cdot}m^{-1}$ in autumn be recommended as for the nutrient solution concentration to produce them safely year round.

• Journal of Bio-Environment Control
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• v.26 no.4
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• pp.317-323
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• 2017

In this study, the heating performance and the energy saving effect of the heat pump system using hot waste water(waste heat) of the thermal power plant discharged from a thermal power plant to the sea were analyzed. The greenhouse area was $5,280m^2$ and scale of the heat pump system was 120 RT(Refrigeration Ton), which was divided into 30 RT, 40 RT and 50 RT. The heat pump system consisted of the roll type heat exchangers, hot waste water transfer pipes, heat pumps(30, 40, 50 RT), a heat storage tank and fan coil units. The roll type heat exchangers was made of PE(Poly Ethylene) pipes in consideration of low cost and durability against corrosion, because hot waste water(sea water) is highly corrosive. And the heating period was 5 months from October to February. During the heating performance test(12 hours), the inlet water temperature of evaporator was changed from $32^{\circ}C$ to $26^{\circ}C$, and heat absorption of he evaporator was changed from 175 kW to 120 kW. The inlet water temperature of the condenser rose linearly from $15^{\circ}C$ to $50^{\circ}C$, and the heat release of condenser was reduced by 40 kW from 200 kW to 160 kW. And the power consumption of the heat pump system increased from 30 kW to 42 kW. When the inlet water temperature of condenser was $15^{\circ}C$, the heating COP(Coefficient Of Performance) was over 7.0. When it was $30^{\circ}C$, it dropped to 5.0, and when it was above $40^{\circ}C$, it decreased to less than 4.0. It was analyzed that the reduction of heating energy cost was 87% when compared to the duty free diesel that the carbon dioxide emission reduction effect was 62% by recycling the waste heat of the thermal power plant as a heat source of the heat pump system.

• Journal of the Korean Society of Radiology
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• v.10 no.5
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• pp.327-335
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• 2016

The study is enforce to study image quality evaluation of condition provide the IEC and combination of clinical conditions each quality of radiation that image quality to assess the conditions provided to IEC in the clinical environment to conduct image quality assessment of the digital radiography system in the detector have environmental limits. First, image quality evaluation was evaluated by measuring the MTF, NPS using four quality of radiation and Using MCNPX simulation lastly DQE make a image quality evaluation after calculating the particle fluence to analyze spectrum quality of radiation. Second, Using MCNPX simulation of four quality of radiation was evaluated absorbed dose rate about electronic 1 per unit air, water, muscle, bone by using Radiation flux density and energy, mass-energy absorption coefficient of matter. Results of evaluation of image quality, MTF of four quality of radiation was satisfied diagnosis frequency domain 1.0 ~ 3.0 lp/mm of general X-ray that indicated 1.13 ~ 2.91 lp/mm spatial frequency. The NPS has added filter, spatial frequency 0.5 lp/mm at standard NPS showed a tendency to decrease after increase. Unused added filter, spatial frequency 0.5 lp/mm at standard NPS showed a certain NPS result value after decrease. DQE in 70 kVp / unuesd added filter(21 mm Al) / SID 150 cm that patial frequency 1.5 lp/mm at standard showed a tendency to decrease after certain value showed. Patial frequency in the rest quality of radiation was showed a tendency to decrease after increase. Results of evaluation of absorbed dose, air < water < muscle < bone in the order showed a tendency to increase. Based on the results of this study provide to basic data that present for the image quality evaluation method of a digital radiation imaging system in various the clinical condition.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2003.04a
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• pp.363-368
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• 2003

We have successfully developed a more effective algorithm to extract the lineament in the area covered by wide alluvial deposits characterized by a relatively narrow range of brightness in the Landsat TM image, while the currently used algorithm is limited to the mountainous areas. In the new algorithm, flat areas mainly consisting of alluvial deposits were selected using the Local Enhancement from the Digital Elevation Model (DEM). The aspect values were obtained by 3${\times}$3 moving windowing of Zevenbergen & Thorno's Method, and then the slopes of the study area were determined using the aspect values. After the lineament factors in the alluvial deposits were revealed by comparing the threshold values, the first rank lineament under the alluvial deposits were extracted using the Hough transform In order to extract the final lineament, the lowest points under the alluvial deposits in a given topographic section perpendicular to the first rank lineament were determined through the spline interpolation, and then the final lineament were chosen through Hough transform using the lowest points. The algorithm developed in this study enables us to observe a clearer lineament in the areas covered by much larger alluvial deposits compared with the results extracted using the conventional existing algorithm. There exists, however, some differences between the first rank lineament, obtained using the aspect and the slope, and the final lineament. This study shows that the new algorithm more effectively extracts the lineament in the area covered with wide alluvlal deposits than in the areas of converging slope, areas with narrow alluvial deposits or valleys.

• Journal of Food Hygiene and Safety
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• v.30 no.2
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• pp.189-195
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• 2015

To determine the contents of sodium (Na) and potassium (K) for restaurant dishes, 194 cases classified 26 kinds of restaurant dishes were collected from restaurants in Seoul and were analysed using the atomic absorption spectroscopy. Average contents of Na and K in Kimchi among restaurant dishes were highest as $554.9{\pm}155.5mg/100g$, $225.1{\pm}69.1mg/100g$, while average contents of Na and K were lowest in Seolleongtang as $24.2{\pm}5.8mg/100g$, $12.7{\pm}3.9mg/100g$ respectively. The contents between Na and K in restaurant dishes had a strong correlation of positive linear judging from 0.782 (p-value < 0.01) of the correlation coefficient. The Na/K ratio of Bulgogi was appropriate as $1.17{\pm}0.44$, while those of Udon, banquet noodles, Kalguksu were very high as shown more than 10. The contents of Na and K were examined 5 dish groups as Gook/Tang, Jjigae/Jeongol, stir-fried dish, noodle and Kimchi. Average contents of Na and K classified by dish groups were significantly difference (p-value < 0.001). Average content of Na among dish groups was highest in Kimchi as $554.9{\pm}155.5mg/100g$ followed by Jjigae/Jeongol, Gook/Tang, stir-fried dish and noodle. Similar to Na content, average content of K was highest in Kimchi as $225.1{\pm}69.1mg/100g$ followed by stir-fried dish, Jjigae/Jeongol, Gook/Tang and noodle. The ratio of Na/K by classified groups of dishes was shown as significantly difference (p-value < 0.001). Stir-fried dish was $1.18{\pm}0.44$ close to 1 followed by Kimchi, Jjigae/Jeongol, Gook/Tang, and noodle.

• Journal of The Korean Society of Grassland and Forage Science
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• v.22 no.1
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• pp.69-76
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• 2002

This pot experiment was conducted to find out the forage productivity and contents of mineral nutrients in an orchardgrass sward as affected by the compost lime, and phosphorus applications on the newly reclaimed and arable pasture soils. This 1st part was concerned with the effect of compost application. The results obtained are summarized as follows: 1. There were considerable differences between the newly reclaimed and arable pasture soils in the soil chemical properties as fellows(newly reclaimed soil ↔ arable pasture soil): poor ↔common in pH and contents of Ca and Mg; Poor ↔ good in content of available P$_2$O$_{5}$, base saturation, and mutual balance of Ca : Mg : K; common ↔ good in K content; good ↔ good in absorption coefficient of P$_2$O$_{5}$; poor ↔ somewhat poor in CEC. The contents of available P$_2$O$_{5}$ in both soils after experiment were relatively higher in the compost block than non-compost block. It was recognized that the compost application was resulted in the CEC increase in the newly reclaimed soil. 2. The vigour at early growth of orchardgrass was better in the arable pasture soil then newly reclaimed soil. In the newly reclaimed soil, the vigour at early growth of orchardgrass was remarkedly enhanced by compost application. 3. Under the non-compost application, the orchardgrass yield was higher in the arable pasture soil by 50.9% than newly reclaimed soil. Compared with the non-compost application, the orchardgrass yields were increased in the newly reclaimed soil by 17.1% and the arable pasture soil by 7.6% by the compost application. 4. The concentrations of Ca, Mg, and P in orchardgrass were relatively higher in the arable pasture soil than the newly reclaimed soil, whereas there was no difference in the K concentration. It was recognized that the concentrations of Mg and P in orchardgrass were higher in the compost block than the non-compost block.block.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.2
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• pp.272-277
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• 1998

Filtering rates of two farming ascidians Styela clava and S. plicata, and of a farming mussel Mytilus edulis were experimentally investigated with reference to effects of water temperature and size. Absorptiometric determinations of filtering rates were carried out in a closed system with experimental animals being decreased indicate dyes neutral red. Optical density (OD) of 440 nm in path length 22 mm cell used as the indication of food particles absorption was appeared directly in proportion with the concentration of neutral red dyes. The filtering rate F is calculated by Kim's equation $F\;=\;V(1-e^{-z})$, where V is the water volume ($\ell$) in the experimental jar, and Z is the decreasing coefficient of OD as meaning of instantaneous removal speed as In $C_t\;=\;In\;C_{o}-Z{\cdot}t$, in this formula $C_t$ is OD at the time t. Filtering rate of S. clava increased as exponential function with increasing temperature while not over critical limit, and the critical temperature for filtering rate was assumed to be between $28^{\circ}C$ and $29^{\circ}C$. In case of S. plicata, the critical temperature was to be below $13^{\circ}C$, and through the temperature range $15\~25^{\circ}C$ appeared a little difference in level even though with significant. M. edulis was not appear any significant effects by water temperature less than $29^{\circ}C$. The model formula derived from the results is as below, where F is filtering rate (${\ell}/hr/animal$), T is water temperature ($^{\circ}C$), and DW is dry meat weight (g) of experimental animal. $$S.\;Clava;\;F\;=\;e xp\;(0.119\;T-4.540)\;(DW)^{0.6745},\;T<29^{\circ}C$$) $$S.\;plicata;\;F\;=\;e xp\;(A_t)\;(DW)^{0.5675},\;(13^{\circ}C $$[A_t =-8.56+0.6805\;T-0.0153\;T^2]$$ $$M.\;edulis;\;F\;=\;0.3844\;(DW)^{0.4952},\;<29^{\circ}C$$)

• Korean Chemical Engineering Research
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• v.56 no.1
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• pp.85-95
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• 2018

In this research, a biofilter system equipped with a biofilter process and a humidifier composed of a fluidized aerobic and an anoxic reactor, was constructed to treat odorous waste air containing hydrogen sulfide, ammonia and VOC, frequently generated from pig and poultry housing facilities, compost manufacturing factories and publicly owned facilities. Its optimum operating condition was revealed and discussed. In the experiment of complex feed, the ammonia of fed-waste air was removed by ca. 75% and more than 20% at the stage of the humidifier and the biofilter, respectively. The toluene of the fed-waste air was removed by ca. 20% and more than 70% at the stage of the humidifier and the biofilter, respectively. Therefore the water-soluble ammonia and the water-insoluble toluene were treated mainly at the stage of the humidifier and the biofilter, respectively. In addition, hydrogen sulfide was almost absorbed at the stage of the humidifier so that it was not detected at the biofilter process. In the experiment of ammonia-containing feed, the ammonia of fed-waste air was removed by ca. 65% and 35% at the stage of the humidifier and the biofilter, respectively. Its removal efficiency of ammonia at the stage of the humidifier was 10% less than that in the experiment of complex feed, due to no supply of such carbon source as toluene required in the process of denitrification. In the experiments of complex feed, ammonia-containing feed with and without (instead, glucose) the addition of yeast extract, the absorption rates of ammonia-nitrogen were ca. 0.28 mg/min, 0.23 mg/min and 0.27 mg/min, respectively. The corresponding denitrification rates in the anoxic reactor were 0.42 mg/min, 0.55 mg/min and 0.27 mg/min, respectively. In addition, in the modeling of bubble column(the fluidized aerobic reactor of the humidifier) process, the value of specific surface area(a) of bubbles multiplied by enhanced mass transfer coefficient (E $K_y$) was evaluated to be 0.12/hr.

• Journal of Preventive Medicine and Public Health
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• v.28 no.4 s.51
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• pp.863-873
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• 1995

This report describes a preperation and characterization of canine blood lead(Pb) standard reference material(SRM). Three adult beagle dogs(A, B, and C)were orally dosed with gelatin capsules containing $Pb(NO_3)_2$, equivalent to $10\sim80mg$ Pb/kg body weight. Blood was drawn 24 hours after the dose from the cephalic vein into lead free 500ml Pyrex beaker in which EDTA.K was contained as an anticoagulant. The amount of lead given to individual dog was varied arbitrarily. Three month later, 3 canine animals were orally dosed with lead secondarily to make mixed SRM(D1) which was mixed different concentrations of lead in bloods with A1, B1, and C1 in vitro. The SRMs for A, B, C, A1, B1, C1, and D1 were distributed 2ml each into more than 300 lead free bottles, and were stored in refregerator at $4^{\circ}C$. The amount of lead in canine whole blood samples were determined using a Varian 30A atomic absorption spectrophotometer(AAS) with a model GTA-96 graphite tube atomizer with D2 background correction and a Hitachi Z-8100 AAS with Zeeman background correction. The sensitivity and detection limits for lead determination of Varian 30A were $0.46{\mu}g/L,\;0.34{\mu}g/L,\;and\;0.56{\mu}g/L,\;0.14{\mu}g/L$ of Hitachi Z-8100, respectively. Day to day variations in determination of blood lead concentration in a certain sample were $31.11{\pm}1.36{\mu}g/100ml$ by Varian 30A, and $33.08{\pm}0.82{\mu}g/100ml$ by Hitachi Z-8100, showing the difference of 3% between the two results. At the blood lead concentrations of $56.31{\pm}1.98{\mu}g/100ml(A),\;40.89{\pm}0.80{\mu}g/100ml(B),\;59.01{\pm}1.38{\mu}g/100ml(C)$, the precisions of replicated measurements by AAS were 3.52%, 1.96%, and 2.34%, respectively. Coefficient variation(CV) of SRMs(A, B, and C) within a standard sample were ranged from 0.92% to 7.50%, and those between 5 standard samples were 1.21%, 2.64%, and 1.11%, respectively, showing inter-vial variation of $1{\mu}g/100ml$. Lead levels in SRMs during one month storage were unchanged. The overall recoveries were $89.6\sim100.4%,\;91.6\sim101.9%,\;90.3\sim100.0%$ for A, B, and C SRMs, means were $56.46{\pm}2.69{\mu}g/100ml,\;39.35{\pm}1.89{\mu}g/100ml,\;57.40{\pm}2.31{\mu}g/100ml$, and measurement ranges were$52.88{\pm}59.26{\mu}g/100ml,\;37.47{\pm}41.68{\mu}g/100ml,\;54.80{\pm}60.69{\mu}g/100ml$, respectively. Those results were laid within confidence limits values. The lead concentrations in the mixed sample(D1) stored over one month period were ranged from $32.76{\mu}g/100ml\;to\;33.54{\mu}g/100ml$, with CV ranging from 1.2% to 2.7%. The results were similiar to each of single samples(A1, B1, and C1) in respect of homogeneity and stability. Results of the mixed blood sample analysed after 1 month storage at $4^{\circ}C$ by four other laboratories(L1, L2, L3, L4) were similar with those of our laboratory($L5;31.18{\pm}0.24{\mu}g/100ml$, acceptable range by $CDC;25.18\sim37.18{\mu}g/100ml$), showing the concentrations of $25.91{\pm}1.19{\mu}g/100ml(L1),\;34.16{\pm}0.22{\mu}g/100ml(L2),\;35.68{\pm}0.85{\mu}g/100ml(L3),\;30.95{\pm}0.46{\mu}g/100ml(L4)$ in a each samples.

• Korean Journal of Soil Science and Fertilizer
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• v.8 no.4
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• pp.189-194
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• 1975

On a newly reclaimed acidic soil, investigation was made to find out the influence of lime and P application at a largeg uantity on the uptake of Zn by corn and its distribution among the leaves, under afactorial combination with two levels of Zn, lime, and P. The results are summarized as following. 1. The application of lime for neutralization of soil significantly reduced the uptake of Zn by corn. 2. Liberal doses of P (5% of P absorption coefficient of soil; 500ppm) applied before sowing did not influence the uptake of Zn. 3. The concentration of Zn in bottom leaves better reflected the Zn uptake status of corn than the upper leaves. The concentration of Zn in bottom leaves responded clearly to the treatments of lime and Zn, while those of upper leaves tended to be constant unresponding to application of lime and Zn. 4. On the present experimental condition, the yield of corn was increased with the increase of P application. But the concentration of P in plant tissue remained constant under different P levels. 5. Application of lime (calcium hydroxide) on low P plots, depressed the yield of corn significantly. It was speculated that the lime applied at large dose made the applied P less available to corn.