• Journal of Ecology and Environment
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• v.42 no.4
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• pp.174-182
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• 2018

Background: In this study, we observed their growth and physiological responses using a variety of duty ratio under the mixed light using red, blue, and white lights. The red+blue mixed light was treated with 95%, 90%, 85%, 80%, and 75% duty ratios and red+blue+white mixed light with 85% and 70% duty ratios. We examined the width and length of leaves, total number of leaves, and number of shoots to examine their growth responses. The physiological responses were studied by measuring their photosynthetic rate, transpiration rate, stomatal conductance, water use efficiency, chlorophyll content, and fluorescence ($F_o$, $F_m$, and $F_v/F_m$). Results: We found that lower duty ratio caused the length and width of the leaves to grow longer under red+blue mixed light but that it did not cause any difference in the red+blue+white mixed light condition. In addition, there was no difference in the number of leaves and shoots among all treatments. In the red+blue mixed light condition, the photosynthetic rate was no difference, but both transpiration rate and stomatal conductance were the highest at 95% duty ratio than in other ratios. Water use efficiency pattern was similar to that of photosynthetic rate; water use efficiency was no difference. Chlorophyll content was the highest at 95% duty ratios, and it was the least at 90%, 85%, and 75% duty ratio. $F_o$ and $F_m$ values were relatively high at 85% and 80% duty ratio and low at 90% duty ratio while $F_v/F_m$ showed no difference. Conclusions: Under the red+blue+white mixed light, all physiological items showed no difference between 70 and 85% treatments. But, photosynthetic rate, water use efficiency, chlorophyll content, and $F_v/F_m$ were relatively greater in the red+blue+white mixed light than in the red+blue mixed light. Therefore, red+blue+white mixed light treated with 70% duty ratio could lessen the environmental stress and save more power when cultivating Silene capitata in a plant factory.

• Journal of agricultural medicine and community health
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• v.6 no.1
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• pp.13-24
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• 1981

This study was conducted with 478 farm households located in Pyongtaek Gun of Gyonggi Do, Chongju City and Chongwon Gun of Chung Buk Do, and Hongchon Gun of Gangwon Do for the period of 10, September through 20, October 1980. It dealt with general features of the farmhouseholds, their practices of handling and using pescides, and relationship between safe use of pesticides and poisoning experiences. The results of the study are summarized as follows: 1. Of the total, 63.2% purchased pesticides mainly through the Agricultural Coops, and 95.4% transported them home separately from other goods. 2 Pesticides were sold contained mainly in glass bottles and paper bags. 3. Mixing of the respodents (87.5%) stored pesticides in sheds, warehouses and boxes. 4. Mixing containers and measuring tools were not used by the majority of the group studied. This indicates that there exist serious problems of safety and accuracy with regard to use of pesticides. 5. As to pesticide protective devices, gloves, respirators, goggles and boots were not used in general. Even in case of using them, their quality was not satisfactory. 6. Among the interviewees, 4.2% did not read pesticide label, 33.9% did not wash immediately when pesticide was spilled on the skin, 48.4% did not care the wind direction during pesticide application, and 17.0% did not wash hands when smoking a cigarette while pesticide is being handled. 7. Of the total, 40.4% were found to harvest vegetables within 10 days from the date of pesticide application, which indicates their unawareness of possible hazards by pesticide residues. 8. Empty pesticide containers or bags were not properly disposed of by majority of the respondents. Furthermore, impacts on the environment by the misuse or abuse of pesticides were not understood by 67.6% 9. Of the interviewees, 48.7% were found to have not received instructions on safe use of pesticides. 10. The rate of pesticidal poisoning experience was about 28.0% if minor symptoms excluded, and it rose to about 44.0% if included. Meanwhile, the rate of pesticidal poisoning tends to increase with the size of farm. 11. The study failed to show a statistically significant relationship between the rate of pesticidal poisoning and use of mixing container and/or measuring tools. However, use of gloves showed a statistical significance on the rate of pesticidal poisoning. 12. Among the poisoned cases, 19.0% were cared for in either hospitals or clinics.

• Journal of Microbiology and Biotechnology
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• v.16 no.3
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• pp.414-422
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• 2006

Before applying PVA bio-beads to practical biological treatment of nitrate-containing wastewater, their characteristics were examined. PVA bio-beads could steadily produce nitrogen gas from nitrate for 28 batches with 0.04 ml/l/h of the maximum gas production rate; however, the maximum gas production rate dropped remarkably thereafter with apparent deformation of beads. Addition of 2.2% solution containing 1% casamino acid, 1% yeast extract, 0.1% mineral solution, and 0.1% vitamin solution to the culture medium resulted in not only recovery of activity of deactivated beads, but also a higher rate of gas production. Calculation of economic benefit for the use of bio-beads in a long-run operation indicated that reactivation of bio-beads by chemicals had economical advantages over packing new bio-beads in the system. The continuously stirred bioreactor exhibited a satisfactory performance at HRT of 20.0 h. With a 9.5 mg $NO_{3}^{-}N/l/h$ nitrate removal rate, nitrate could completely be removed without nitrite accumulation. The use of PVA bio-beads in nitrate removal appears very promising.

• Korean Journal of Animal Reproduction
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• v.20 no.1
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• pp.9-17
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• 1996

This study was conducted to investigate freezability of in vitro and in vitro matured rabbit oocytes, possibility of NT using frozen-thawed unfertilized oocytes, and NT efficiency by zona-slit micromanipulation. After freezing of in vitro matured oocytes, 33 to 49% of oocytes appeared normal morphology and 1.0M DMSO and 1.5M glycerol showed slightly high survival rate, but there was no difference in survival between two cryoprotectants. Freezability of in vitro matured oocytes was low in 1.5M glycerol and more sensitive to freezing. Efficiency of enucleation and fusion rate in method B was higher than that in method A and no difference in this efficiency was between 3 groups of oocytes in method B. Cleavage rate and developmental capacity to M＋B stage of fused embryos derived from frozen oocytes was greatly lower than that from fresh oocytes, respectively(39.1% : 79.5% ; 3.1% : 19.3%) and there was no difference in cleavage rate between DC voltages in two group oocytes. Additional incubation in cytochalasin B after electrical stimulation did not affect embryo development. In conclusion, it is suggested that enucleation and nucelar transfer by slitting of zona is more effective method in rabbit and that further study on optimum freezing conditions for in vitro matured oocytes is necessary to use as recipient oocytes.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.11a
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• pp.274-278
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• 2011

We present an innovative method of multi-physics application involving energetic materials. We use an Eulerian methodology to address these problems. We have devised a new level set based tracking framework that can elegantly handle large gradients typically found in energetic response of high explosive and metals. Proper constitutive relations are employed to model the transient phases of gas, lliquid, and solid in the high strain rate regime. We use the confined and unconfined rate stick results to validate against the experimental data.

• Journal of Korean Neurosurgical Society
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• v.53 no.3
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• pp.150-154
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• 2013

Objective : To evaluate the effect of electromagnetic (EM) navigation system on ventriculoperitoneal (VP) shunt failure rate through comparing the result of standard shunt placement. Methods : All patients undergoing VP shunt from October 2007 to September 2010 were included in this retrospective study. The first group received shunt surgery using EM navigation. The second group had catheters inserted using manual method with anatomical landmark. The relationship between proximal catheter position and shunt revision rate was evaluated using postoperative computed tomography by a 3-point scale. 1) Grade I; optimal position free-floating in cerebrospinal fluid, 2) Grade II; touching choroid or ventricular wall, 3) Grade III; tip within parenchyma. Results : A total of 72 patients were participated, 27 with EM navigated shunts and 45 with standard shunts. Grade I was found in 25 patients from group 1 and 32 patients from group 2. Only 2 patients without use of navigation belonged to grade III. Proximal obstruction took place 7% in grade I, 15% in grade II and 100% in grade III. Shunt revision occurred in 11% of group 1 and 31% of group 2. Compared in terms of proximal catheter position, there was growing trend of revision rate according to increase of grade on each group. Although infection rate was similar between both groups, the result had no statistical meaning (p=0.905, chi-square test). Conclusion : The use of EM navigation in routine shunt surgery can eliminate poor shunt placement resulting in a dramatic reduction in failure rates.

• International Journal of Highway Engineering
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• v.16 no.6
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• pp.181-189
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• 2014

PURPOSES : Ambiguous decision on whether rural or urban area for road design can increase the construction cost and restrict the land use of surrounding area. However, administrative classification on rural and urban area is not directly related to road design because of this classification is not based on the engineering viewpoint, so method which can explain the road design context is required. METHODS : Method which enables to identify the area for road design is suggested based on the deceleration expected to be experienced by drivers who use the road section concerned. Deceleration rate corresponding to the area such as rural or urban suggested in Road Design Guideline is used as the criteria to identify the area by comparing this value with the estimated deceleration rate at the road section concerned. Speed profile method is utilized to derive the deceleration rate, and speed estimation way for reflecting both road geometry and intersection is suggested using stopping sight distance concept. RESULTS : The procedure of the method application is suggested, and the design example utilizing the method is provided. CONCLUSIONS : The method is expected to be used to identify the area for road design with engineering viewpoint, and design consistency among the roads with similar driving environment can be made.

• Journal of Forest and Environmental Science
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• v.32 no.3
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• pp.253-261
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• 2016

Xanthoceras sorbifolia seed coat (XSSC) is a processing residue of the bioenergy crop. This work aimed to evaluate the applicability of using the steam explosion to modify the residue for dye biosorption from aqueous solutions by using methylene blue as a model cationic dye. Equilibrium, kinetic and thermodynamic parameters for the biosorption of methylene blue on the steam-exploded XSSC (SE-XSSC) were evaluated. The kinetic data followed the pseudo-second-order model, and the rate-limiting step was the chemical adsorption. Intraparticle diffusion was one of the rate-controlling factors. The equilibrium data agreed well with the Langmuir isotherm, and the biosorption was favorable. The steam-explosion pretreatment strongly affected the biosorption in some respects. It reduced the adsorption rate constant and the initial sorption rate of the pseudo-second-order model. It enhanced the adsorption capacity of methylene blue at higher temperatures while reduced the capacity at lower ones. It changed the biosorption from an exothermic process driven by both the enthalpy and the entropy to an endothermic one driven by entropy only. It increased the surface area and decreased the pH point of zero charge of the biomass. Compared with the native XSSC, SE-XSSC is preferable to MB biosorption from warmer dye effluents.

• International Journal of Industrial Entomology and Biomaterials
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• v.7 no.2
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• pp.175-180
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• 2003

Changes in biochemical constituents and physiological alteration were studied in various intensities (1-5%, 6-15%, 16-30%, 31-50% and ＞ 50%) of leaf spot (Myrothecium roridum) on mulberry leaves and compared with healthy leaves. Chlorophyll, total soluble sugar and total protein were decreased (P ＜ 0.01), but total phenol increased due to pathogen infection. Changes in biochemical constituents showed significant correlation with intensity of disease. Chlorophyll ($r^2$= 0.92), and protein (($r^2$= 0.83) possessed negative while phenol (($r^2$= 0.61) possessed positive correlation. Photosynthetic rate, transpiration rate, stomatal conductance, moisture content (%) and physiological water use efficiency (pWUE) were decreased, but stomatal resistance increased in the infected leaves. Physiological parameters also possessed significant (P ＜ 0.01) correlation with disease intensity. Photosynthetic rate (($r^2$= 0.96), transpiration rate ($r^2$=0.88), stomatal conductance (($r^2$= = 0.65), physiological water use efficiency (($r^2$= 0.88) and moisture content (r = 0.85) were negatively but stomatal resistance (($r^2$= 0.75) was positively correlated to disease intensities.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.28 no.3
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• pp.26-35
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• 2005

This paper is intended to compare the hazard rate estimations from Bayesian approach and maximum likelihood estimate(MLE) method. Hazard rate frequently involves unknown parameters and it is common that those parameters are estimated from observed data by using MLE method. Such estimated parameters are appropriate as long as there are sufficient data. Due to various reasons, however, we frequently cannot obtain sufficient data so that the result of MLE method may be unreliable. In order to resolve such a problem we need to rely on the judgement about the unknown parameters. We do this by adopting the Bayesian approach. The first one is to use a predictive distribution and the second one is a method called Bayesian estimate. In addition, in the Bayesian approach, the prior distribution has a critical effect on the result of analysis, so we introduce the method using computerized-simulation to elicit an effective prior distribution. For the simplicity, we use exponential and gamma distributions as a likelihood distribution and its natural conjugate prior distribution, respectively. Finally, numerical examples are given to illustrate the potential benefits of the Bayesian approach.