• Journal of the Korea Organic Resources Recycling Association
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• v.10 no.2
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• pp.65-70
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• 2002

The previous studies showed that rumen microorganisms had an enhanced waste-degrading capability and controlling the dilution rate was very effective in improving acidification efficiency. Generally the composition of food waste has a small deviation value, but one of the waste components (grains, vegetables or meats) can be increased dramatically depending on a seasonal variation. Thus, it is important to evaluate the efficiency of acidogenic fermentation in this case. Each component was spiked to be 80% of the total waste in R1 (grains), R2(vegetables), and R3 (meats). In Rl, rapid degradation occurred during the initial two days. R2 showed similar performance to that of general food waste. In R3, degradation retarded in the initial stage and then increased after controlling the dilution rate. The acidification efficiencies of the reactors were 88.7 (R1), 73.5 (R2), and 62.1% (R3), respectively. Therefore, the fermentation efficiency was kept over 62% regardless of waste components, indicating that it was stable to acidify food waste by employing rumen microorganisms and controlling the dilution rate.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.455-456
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• 2000

Characteristics of $CO_2$ fixation by Chlorella sp. HA-1 were studied in a semi-continuous mode in a series operation. A high $CO_2$ fixation rate for a long time was obtained, when the method of semi-continuous mode was employed, in which the controlling parameter was the dilution ratio. A constant $CO_2$ fixation rate was maintained even when the dilution ratio was increased with the increment of 0.1 at the initial value of 0.5. The method of series operation was used to improve the efficiency of $CO_2$ fixation. The total amount of $CO_2$ fixation was proportion to the number of reactor in series operation.

• Journal of Welding and Joining
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• v.35 no.3
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• pp.28-34
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• 2017

The authors derived the criteria on the process parameters of laser depositions with metal powers(SUS316L & IN718) by evaluating the surface and cross-section properties of the deposition layers. The surface characteristics of the deposition layer are investigated through optical microscopy by controlling the process parameters of laser output, powder feeding rate and gas feeding rate. The cross-section characteristics were also analyzed after polishing and chemical etching process. As the gas feeding rate increased, the amount of powder loss increased and the difference in the dilution ratio and heat affected zone depending on laser outputs was observed. In addition, the powder feeding rate used in the experiment did not interfere with the energy absorption of the base material.

• Journal of the Korea Organic Resources Recycling Association
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• v.8 no.3
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• pp.118-123
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• 2000

Food waste results in various problems such as decay, odors and leachate in collection, transportation and landfill due to the high volatile solids and moisture content. Acidogenic fermentation of food waste is influenced by the environmental conditions such as pH, retention time, etc. Each component of food waste is degraded under the different environmental conditions. Starch, cellulose and protein have their own optimum pHs and retention times for degradation. The degradation of starch increases at low pH, cellulose with increasing retention time, and protein with increasing retention time as well as approaching neutral pH. These mean that the degradation of food waste can be enhanced by adjusting the environmental conditions of acidogenic fermentation. The efficiency of acidification increased from 71.2 to 81.1% by controlling dilution(D) rate from 3.0 to $1.0d^{-1}$ depending on the state of the fermentation. The main component of the acidified product was shifted from butyric to acetic acid, indicating that the increase of acidification was mainly caused by the enhanced degradation of vegetables and meats.

• Journal of Biosystems Engineering
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• v.38 no.4
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• pp.228-239
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• 2013

Purpose: The objectives of this study were to develop an automated disinfectant dilution system, and an automated data management system for spraying amount for resolving uncertainty problem. Methods: Proper diluting rate was made by a controlled volume pump for liquid disinfectant and a screw conveyer pump for solid disinfectant. The water capacity of disinfecting system of 400 L was controlled by two water level sensors. The water quantity of water tank was controlled by the signals which were produced by the water level sensors. Signals were processed by Labview Programming, and ON/OFF of solenoid valve that was used for controlling water supplying to water tank, was controlled by SSR. The operating time of pumps for disinfectant was controlled quantitatively. A turbine flowmeter was used for development of automated measurement system for spraying amount of disinfectant. In order to save the flowmeter data and to control the spraying system, a multi-function data logger was used, and it was processed and saved in Excel file by a program developed in this study. Results: Labview 2010 was used for programming to control the automated measurement system for spraying amount of disinfectant. Results showed that the relationship between flowmeter value and time had a significant linear relationship such as 0.99 of $R^2$. Generally, 6.74 L/s of diluted disinfectant is sprayed for a vehicle passing through the disinfection system (about 15 seconds). Test results showed that average error between the measured spraying amount and the flowmeter data was 50 mL, and the range of error was 1.3%. Since the amount and time of spraying could be saved in real-time by using the spreadsheet files which could not be modified arbitrarily, it made possible to judge objectively whether the disinfection spraying was performed or not. Test results of spraying liquid and solid disinfectant showed that the errors between the measured discharge rate and the theoretical one were ranged within 3-4% for various dilution rates. Conclusions: The disinfection system developed would be working accurately. The automated spraying data base management system satisfied the purpose of this study. The automated dilution process system developed in this study could discharge liquid and solid disinfectant with accurate dilution rate, relatively.

• Korean Journal of Environmental Biology
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• v.22 no.4
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• pp.501-506
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• 2004

In organic agriculture, choose of effective and cheap bio-pesticide is very important. The authors developed an insecticidal extract from neem cake, waste of neem oil from kernel, and applied as a bio-pesticide. Bio-pesticide neem cake extracts experiment on cabbage pest was carried out at Wonju Agricultural Technology and Extension Center from 11 March to 30 May 2003. There were six treatments with three replications, using completely randomized design. Treatments involved three and six sprays of synthetic pyrethroid pesticide cypermethrin 10 EC at the dilution rate of 2.2 mL $L^{-1}$ of distilled water and four, five and six sprays of bio-pesticide neem at the dilution rate of 13.3 mL $L^{-1}$ of distilled water, and untreated control. For each treatment, designated sprayings were done at 7 days interval. Pre-spray data showed that the plants in all the experimental plots were already infested with aphid (Aphis gossypii), and diamondback moth (Pluetella xylostella). The results indicated that all neem pesticide treatments were more effective in insecticidal activity than the untreated control and the chemical treatments in controlling aphids and diamondback moth. Among the three neem treatments, there were no significant differences between them.

• KSBB Journal
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• v.14 no.6
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• pp.742-746
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• 1999

The microalgal, Chlorella sp. HA-1, had good $CO_2$ fixation efficiency compared to other algal strains at the same operating condition. In this study, Chorella sp. HA-1 showed similar tolerance both 10% and 20% $CO_2$ concentration. By optimization of the major operation variables such as pH, initial cell concentration, light intensity, the $CO_2$ fixation rate could be raised to a reasonably high value, 372 $gCO_2/m^2{\cdot}day$ in a 3 L internally illuminated photobioreactor. In order to maintain the $CO_2$ fixation rate for a long time, the method of semi-continuous operation was employed, in which dilution ratio was the controlling parameter. Starting with the dilution ratio of 0.5 with the increased increment of 0.1, the constant $CO_2$ fixation rate was obtained.

• The Korean Journal of Pesticide Science
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• v.14 no.1
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• pp.49-53
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• 2010

Disease control efficacy was evaluated with use of Bacillus subtilis KB-401 against cucumber powdery mildew in a greenhouse and fields. B. subtilis KB-401 showing inhibitory effect on mycelial growth of various phytopathogenic fungi was formulated for the evaluation. The formulated biofungicide of B. subtilis KB-401 was less effective at 1,000 times dilution rate than that at 250 or 500 times dilution rate. The powdery mildew was successfully controlled by the biofungicide at the early stage of disease development. The field performance of the biofungicde was conducted in Asan and Cheonan city. Three or four consecutive applications of the biofungicide at 500 dilution rate with 10-day intervals resulted in considerable efficacy of disease control as high as 83.3%.

• Microbiology and Biotechnology Letters
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• v.17 no.1
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• pp.19-23
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• 1989

A sequential system composed of hydroxylapatite chromatography and gel permeation chromatography was developed to purify the IgM type monoclonal antibody against the colon cancer cell SC-1 from the ascitic fluid of mice injected with the murine hybridoma CH07E02. In the hydroxylapatite chromatographic step the band dilution could be reduced by controlling the gradient and flow rate of the eluent, the sodium phospate buffer, the optimum values for these variables being 5.82$\times$10$^{-3}$M/cm and 0.2$m\ell/\textrm{cm}^2$/min, respectively. A degree of purity better than 99.99% as judged from silverstaining of the SDS-PAGE bands, was obtained by adding the gel permeation chromatographic step in tandem.

• Research in Plant Disease
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• v.12 no.3
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• pp.240-248
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• 2006

Control of white rot which is one of the most serious apple diseases in Korea has mainly relied on periodical spray of protective fungicides. As the main inoculum source of the disease is pycnidiospores produced in the warts formed on affected stems of apple tree, it can be conceivable that inhibition of spore production might be an effective means for controlling the disease. Inhibitory efficacy of eight selected fungicides against sporulation of the fungus was assessed by counting the number of spores produced at detached warts treated with the fungicides of recommended dilution. They showed diverse effect on sporulation. Carbendazim and azoxystrobin suppressed sporulation almost completely, the former irreversively. Thiram and folpet promoted sporulation as producing much more number of spores than untreated control. Others showed almost no effect on sporulation. Effects of suppression and promotion in the sporulation shown by the fungicides on the control of white rot were examined by incidences of disease and infection at the plots adopted the spray programs of which the fungicide at late May was substituted by carbendazim, azoxystrobin, folpet and thiram, respectively. Disease incidence and infection frequency at the plots sprayed former two chemicals which suppressed sporulation were much lower than those of the plots adopted latter two chemicals and untreated plot at which the fungicide spray was skipped at that time. These facts were reconfirmed in the experiments conducted with carbendazim and thiram, in which 100 fruits were bagged just prior to each spray from late May to late July for elucidating the effect of the two fungicides on the action of subsequent ones. Disease incidence and infection frequency on the fruit bagged just prior to each spray were gradually increased as the seasons going on. The increase rate at the carbendazim plot was much lower than that of thiram. Especially, the fruit infected till late July at the carbendazim plot were almost completely cured by the three fungicides, iminoctadine-triacetate, tebuconazole and samzinwang, a combined formular of iminoctadine-triacetate and difenoconazole, sprayed at late July and hence. In thiram plot, infected fruit were also cured by the 3 fungicides but not remarkable. From these results, it can be concluded that control efficiency of white rot can be greatly enhanced by selecting the fungicide capable of suppress the sporulation of white rot fungus at the season when the mass dispersal of spores is not initiated.