• Journal of Korean Society of Forest Science
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• v.83 no.2
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• pp.221-228
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• 1994

Respitation and growth rates of leaves, branches, stems and roots of 2 to 11-yr-old red pine trees(Pinus densiflora) were examined and applied to Thornley's growth equation, $$R=(\frac{1-Yg}{Yg})\frac{dW}{dt}+mW$$. The conversion efficiency of substrates(Yg), maintenance respiration coefficients(m), relative growth rates(${\mu}$) were estimated. The efficiency of conversion of substrates (Yg) was 0.3637g/g dw/yr and the maintenance respiration coefficient(m0 was 0.094g/g dw/yr. The relative growth rate(${\mu}$) was remarkably reduced with age from 0.90(2-year-old) to 0.33:11 year-old). The Ratio of gross respiration(R) per gross photosynthesis(Pg), R/Pg showed the range of 0.6~0.7 and annually 64% of Pg was spent for constructive respiration. The 3.4% of dry weight of whole tree was spent for maintenance respiration.

• Korean Journal of Food Science and Technology
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• v.31 no.3
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• pp.751-756
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• 1999

The inhibitory effect of antibiotics on growth of lactobacillus, streptococcus and bifidobacteria was examined to develop the selective media to isolate and enumerate bifidobacteria from the fermented foods containing various lactic bacteria. The growth of lactic bacteria was inhibited seriously but that of bifidobacteria was not inhibited by gentamycin or ripampicin at the concentration of more than $100\;{\mu}g/mL$. However lactic bacteria did not grow in MRS broth containing $50\;{\mu}g/mL$ of ampicillin and the growth inhibition of bifidobacteria occurred. The growth inhibition of bifidobacteria was more severe than lactic bacteria in $100\;{\mu}g/mL$ of fosfomycin. Therefore, the MRS medium containing $80\;{\mu}g/mL$ of neomycin sulfate, $50\;{\mu}g/mL$ of gentamycin, $50\;{\mu}g/mL$ of rifampicin, $15\;{\mu}g/mL$ of nalidixic acid and $3\;{\mu}g/mL$ of lithium chloride was concluded selective for bifidobacteria, but restrictive for the other lactic bacteria present in Kimchi and cheese.

• Journal of the Korean Applied Science and Technology
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• v.29 no.4
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• pp.585-593
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• 2012

The EO separation and quantitative determination of polysorbate 20, polysorbate 40, polysorbate 60 and polysorbate 80 was carried out by reversed phase HPLC. The water/acetonitrile was used for the mobile phase of gradient conditions. An YMC Pack Ph ($250mm{\times}4.6mm$ i.d., $5{\mu}m$) and Phenomenex C4 ($250mm{\times}4.6mm$ i.d., $5{\mu}m$) and the selected ELSD detector was applied. The analysis results of HPLC showed good linearity with correlation coefficient of $r^2$=0.997 in the rage of $180.2{\sim}980.5{\mu}g/mL$ and detection limit.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.11 no.4
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• pp.233-238
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• 1978

Rainbow trout were reared in a stainless steel aquarium from Nov. 11, 1977 to June 12, 1978, and the following results were obtained : 1. The volume of water was about $400\iota$ in a aquarium measuring $1m\;(Length)\times1m\;(Width)\times67cm(Height)$ and water depth 40 cm. Water was supplied for about 16 hours daily at a rate $3\iota/min$ and was drained through the conical settling part in the middle of the aquarium bottom. Filter tank was about $23cm(W)\times23cm(L)\times40cm(D)$ and contained pebbles 30 cm in depth. Water recirculation rate was at)out $1,030\iota/hr$, or 2.6 turn-over per hour. 2. During the first period (77 days), the trout grew from 88.3g to 229g in average, the total weight attaining 30.7kg. The food coefficient was 1.249, average daily increment 243.3g, average daily growth rate 1.245%, and the mortality was 2 smallest fish weighing 53 g, owing to unknown reason. During the second period (135 days), the trout grew from 239g to 555g in average, the total weight attaining 57.2 kg. The food coefficient was 1.447, average daily increment 279.8g, average daily growth rate $0.65\%$ and the mortality was 31 fish weighing 11,255 g, owing partly to miss-handling and partly to disease. 3. The feed consisting of fully domestic materials was prepared in this laboratory, and the feed conversion was not inferior to high protein commercial feed available in foreign countries. 4. The result of whole period for 212 days was 56.5 kg in gross increment, and based on this result, when $1\iota/min$ full day inflowing water available, the net production will become 28.25 kg. So, if a 5000kg production is planned, $180\iota/min$ or about $10.8m^3/hr$ be reauired, and the production in value frill become 15million won at local price at the expense of about 5.3 million won. From the result of this experiment, rainbow trout is feasible for commercial production in Korea with relatively small amount of well water and simplified water recirculation system.

• Journal of Biomedical Engineering Research
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• v.23 no.6
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• pp.451-458
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• 2002

Osteoporosis is a systemic skeletal disease caused by low bone mass and the decrease of bone density in the microstructure of trabecular bone. Drug therapy(PTH Parathyroid hormone) may increase the trabecular thickness and thus bone strength. Vertebroplasty is a minimally invasive surgery foy the treatment of osteoporotic vertebral compression fracture. This Procedure includes Puncturing vertebrae and filling with Polymethylmethacrylate(PMMA). Although altering recommended monomer-to-Powder ratio affects material properties of bone cement, clinicians commonly alter the mixture ratio to decrease viscosity and increase the working time. The Purposes of this study were to analyze the effect of 4he monomer-to-powder ratio on the mechanical characteristics of trabecular. In this paper, the finite element model of human vertebral trabecualr bone was developed by modified Voronoi diagram, to analyze the relative effect of hormone therapy and vertebroplasty at the treatment of osteoporotic vertebrae. Trabeuclar bone models for vertebroplasty with varied monomer-to-Powder ratio(0.40∼1.07 ㎖/g) were analyzed. Effective modulus and strength of bone cement-treated models were approximately 60% of those of intact models and these are almost twice the values of hormone-treated models. The bone cement models with the ratio of 0.53㎖/g have the maximum modulus and strength. For the ratio of 1.07㎖/g, the modulus and strength were minimum(42% and 49% respectively) but these were greater than those for drug therapy. This study shows that bone cement treatment is more effective than drug therapy. It is found that in vertebroplasty, using a monomer-to-powder ratio different from that recommended by manufacturer nay significantly not only reduce the cement's material Properties but also deteriorate the mechanical characteristics of osteoporotic vertebrae.

• KSBB Journal
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• v.4 no.1
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• pp.21-30
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• 1989

Lauryl alcohol was used as extracting solvent of ethanol, and its toxicity on the free cells or immobilized cells was tested. To increase ethanol productivity, extractive fermentation method combined with ethanol fermentation and ethanol recovery was applied to the immobilized batch and continuous fermenter. As the concentration of LaOH was increased, the lag phase became longer, but specific growth rate did not change greatly. And a cell entrapment technique could protect the yeast cells against both substrate inhibition and solvent toxicity. When the glucose concentration was 400 g/l and the LaOH/fermentation medium ratio was 4, total ethanol productivity increased with the enhancement of LaOH volume, and maximum productivity was 2.75 g/l.hr in the immobilized batch fermentation.

• Journal of Sensor Science and Technology
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• v.6 no.5
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• pp.385-391
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• 1997

An objection of this study is to develop a measuring circuit of a gauge using radioisotope for compaction control. The gauge developed in this study makes use of radioisotope with the activity exempted from domestic atomic law and consists of measuring circuits for gamma-rays and thermal neutrons, a high voltage supply unit, and a microprocessor. To obtain meaningful numbers of pulse counts, parallel five and two circuits are provided for gamma-rays and thermal neutrons, respectively. Being simple in electrical characteristics of G-M detector for gamma-rays, pulses are counted through only a shaping circuit. Very small pulses generated from He- 3 proportional detector for thermal neutrons are amplified to the maximum of 50 [dB] and a window comparator accepts only pulses with meaning. To minimize effects of natural environmental radiation and electrical noise, circuits are electrostatically shielded and pulses made by ripples are eliminated by taking frequency of high voltage supplied to the circuit and pulse height of ripples into consideration. One-chip microprocessor is applied to process various counts, results are stored and the gauage is made capable to communicate with PC. Enough and meaningful numbers of pulses are counted with the prototype gauage for compaction control.

• Journal of Practical Agriculture & Fisheries Research
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• v.4 no.1
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• pp.128-137
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• 2002

This study was conducted to develop the heat exchanger by utilizing the heat energy of underground water(15℃), which might be used for cooling and heating system of the agricultural facilities. We developed the heat exchanger by using the parallel type plat fin tube made of Aluminum(Al 6063), which was named Aloo-Heat(No. 0247164, offered by Korean Intellectual property Office). The trial manufactures were made from Aloo-heat which was 600mm, 700mm length respectively, and It were welded to the end "U" type in order to direct flow of the underground water. The performance test was carried out under the condition of open space and room temperature with the change of flow rate of the underground water and air. The results are as follows. 1. The trial manufactures had convection heat value from 33 to 156 W/m²℃, and It was coincided with design assumption. 2. The amount of energy transfer was increased with the increment of the area of heat transfer, the air flow, the gap of temperature inlet & outlet the underground water and the air. 3. The heat value was 6,825W when the air flow was 6,000m³/h and the gap of temperature between inlet and outlet of the underground water was 6℃, and It dropped from 25.8℃ to 23.2℃(-2.6℃ difference). The convection heat value was 88.5W/m²℃. 4. The heat value was 2.625W when the air flow was 4,000m³/h and the gap of temperature between inlet and outlet the underground water was 2℃, and It dropped from 27℃ to 22.5℃(-4.5℃ difference). The convection heat value was 33.6W/m²℃. 5. Correlation values(R²) of the testing heat values of the trial manufacture type I, II, and III were 0.9141, 0.8935, and 0.9323 respectively, and correlation values(R²) of the amount of the air flow 6,000m³/h, 5,000m³/h, 4,000m³/h were 0.9513, 0.9414, and 0.9003 respectively.

• Journal of Bio-Environment Control
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• v.18 no.3
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• pp.253-257
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• 2009

To analysis effect of environment factors on productivity of sweet pepper according to greenhouse covering material (glass, plastic film), this was investigated. In glasshouse, outside light was positively correlated with yield as that $100MJ{\cdot}m^{-2}$ of outside light increased $300{\sim}500g{\cdot}m^{-2}$, also cumulative temperature was same tendency. On possibility of model development for yield estimate cumulative temperature was high than outside light. According to covering material, leaf photosynthesis, productivity per out-side light and term in glasshouse was more high 13%, 46%, and 47% compared with plastic film house, respectively. Result of analysis of effect of light, temperature, and $CO_2$ on yield, relative yield coefficient, yield increment coefficient, and yield reduction coefficient in glasshouse were more high 25%, 73%, and 34% compared with plastic film house, respectively. Hence, sweet pepper's growing in glasshouse compare with plastic film house had more productivity, but that had more sensitivity to charge of environment factors.

• Exercise Science
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• v.21 no.2
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• pp.183-190
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• 2012

This study is to evaluate the availability of cardiorespiratory fitness measurement by 20 m shuttle run test based upon energy contribution rates of elite athletes in different sports type. Sixty-seven elite athletes attending K national university participated in this study. They were divided by three groups based upon sports type, composed of Anaerobic Group (sprint, jumps, weightlifting, throw; n=35), Aerobic Group (medium-long distance; n=9), and Combat Sport Group (judo; n=23). 20 m shuttle run test was conducted by Leger et al.(1982) method and calculating acceleration using measured shuttle run repetitions was conducted by Brewer et al.(1988) method. To test the usefulness of VO₂max, graded exercise treadmill test was conducted and standing long jump and 50 m run were measured as power fitness factors. Z-jump was used for measuring power, agility, and muscular endurance. Standing long jump and 50 m run of Anaerobic Group (AnG) was significantly higher than that of Aerobic Group (AeG) and Combat Sport Group (CG) (p<0.05). However, Z-jump of CG was significantly higher than that of AnG and AeG(p<.05). There was a higher correlation of 20 m shuttle run test and VO₂max in AnG(r= 0.577, p<.0001) and CG(r= 0.760, p<.0001). Otherwise, there was a low correlation of 20 m shuttle run test and VO₂max in AeG. There was no significant group difference to test the availability of 20 m shuttle run test and there was a reduced error when converting 20 m shuttle run results into VO₂max. This study examined the usefulness of 20 m shuttle run test by converting 20 m shuttle run repetition results into VO₂max calculation, which showed reduced error. Therefore, this study confirmed that it would be needed to convert 20 m shuttle run results into VO₂max for universal and practical use in the field without dividing sports type.