• Korean Journal of Soil Science and Fertilizer
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• v.9 no.1
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• pp.1-8
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• 1976

1. Under an asumption that Ficks diffusion equation could be applicable in soil systems, the diffusivities of NaCl in several flooded soil systems were measured to range from $0.4{\times}10^{-5}cm^2sec^{-1}$ to $0.83{\times}10^{-5}cm^2sec^{-1}$ 2. It was discussed that, when a polder soil with a uniform initial salt content through the profile is desalinated only by diffusion to flooding water, the salt content in profile is a function of soil depth, diffusion time, and diffusivity as following $$C=C^{\circ}erf\frac{x}{\sqrt[2]{Dt}}$$ 3. On the basis of Kirkham, et al's integration of complementary erra function, the speed of desalting was discussed to be inversely proportional to the square root of time as following $$dq/dt=C^{\circ}{\sqrt{D/{\pi}t}}$$ 4. It was estimated enough to exchange the flooding water once or twice, even when desalination of polder soil is carried out only by diffusion, if the desalination begins in June, the used flooding water is fresh water, and flooding depth is 10cm. 5. Desalination of polder soil by diffusion requires 2 month for good standing of planted rice.

• Korean Journal of Soil Science and Fertilizer
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• v.22 no.1
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• pp.61-66
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• 1989

Plants were exposed to different sub-optimal growth temperature regimes for hardening or sprayed with abscisic acid (ABA) before being placed at $10^{\circ}C$ for three days. Comparisons were made with non-treated plants for plant survival, photosynthetic activities and fatty acids composition of phospholipids. The level of endogenous ABA of the hardened seedlings was compared with that in control and ABA sprayed-seedlings. The results of the above experiment were summarized as follows: 1. Compared to non-treated plants, the hardening and ABA treatment resulted in higher plant survival rate and better seedling growth following earlier transplanting. The low temperature hardening which gradually increased the duration of the low temperature treatment at 2-day intervals was more effective than the controled temperature hardening which gradually decreased the temperature from $25^{\circ}C$ to $20^{\circ}C$ and $15^{\circ}C$. 2. The photosynthetic activities of rice leaves after 3-day exposure to $10^{\circ}C$ were higher in hardened and ABA sprayed seedlings than in non-treated plants. The root activities after low temperature treatment were also higher in hardened and ABA sprayed seedlings than in control. 3. Fatty acids of phospholipids in rice plants such as stearic acid and oleic acid were decreased and the highly unsaturated fatty acids, linoleic acid and lenolenic acid were increased by hardening or ABA treatments. It is assumed that the increase of cold tolerance in these plants was due to the higher ratio of unsaturated to saturated fatty acids. Respectively, the ratio was 1.86, 1.97 and 1.80 in plants given controled temperature hardening, the low temperature hardening and ABA treatments. While in control plants, it was 1.17. 4. ABA content in rice seedling given the low temperature hardening treatment was 67.2 ng/g F.W which was approximately twice that of non-treated control, which was 33.9 ng/f F. W., in contrast, the ABA content of the ABA treated seedlings was 91.7 ng/g F. W.

• Korean Journal of Soil Science and Fertilizer
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• v.38 no.2
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• pp.101-107
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• 2005

To investigate the effect of pyroligneous acid liquor (PAL) on the maturity of pig manure compost, PAL was treated to the compost piles. The treatments included applications of 100 and 300 times diluted PAL in addition to the control. The compost piles were stirred in three times at the 1st, 10th, and 25th day of composting. Temperature in the compost pile of control treatment increased from 28 to $60^{\circ}C$ within 10 days and remained nearly at the level until 30th day, then it began to decrease. On the other hand, temperature of the PAL-100 and PAL-300 treatments reached 65 to $70^{\circ}C$ within 8 days and became stabilized until 30th day, then the temperature decreased to about $28^{\circ}C$. However, the temperature of control was stabilized approximately at the 40th day. Initially, the pH of control treatment dropped from 8.2 to slightly above pH 8.0 during 4th day, but that of the PAL-100 treatment declined to 7.8. Among treatments, pH value of PAL-100 treatment was the lowest, which was about 7.3 after becoming stabilization. Also the germination index (GI) was increased at all treatments. The C/N ratio range of PAL-100 treatment was better balanced than others and was at 24.3. Moreover the round paper chromatogram of extracted solution of compost of PAL-100 treatment was the sharpest and clearest among treatments. The GI values of control, PAL-100, and PAL-300 in 60 days of composting were about 108, 120, and 118 in germination test using chinese cabbage, respectively. It can be concluded that the addition of diluted PAL solution is effective in composting of pig manure.

• Journal of Sericultural and Entomological Science
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• v.50 no.2
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• pp.133-139
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• 2012

The Aims of this study are to investigate ecological environments and indoor-rearing conditions of Eurema hecabe for artificial rearing. Two different nesting site, a open area nearby small river(A area; Daejin-ri, Gonyang-myeon, Sachun-si, Gyoungsangnam-do) and a foot of a hill area(B area; Noryang-ri, Seolcheon-myeon, Namhae-gun, Kyoungsangnam-do), selected for investigation of ecological habitat environment, and investigated two times per month, during six month, from June to November in 2010. In result, the number of butterflies, Eurema hecabe, at the hill area(B area) was 6 times more than the open area(A area). We observed the number of eggs, larvae and puapae in the B area more times compared to those in the A area. In the B area, Lespedeza cuneata was higher preference than the other host plant, Lespedeza pilosa and Albizia julibrissin. For development of indoor-rearing conditions, common grass yellow butterfly, Eurema hecabe, was reared in a room condition. As a result of oviposition preference experiment, 100-mated-female laid significantly higher number of eggs $104.9{\pm}19.6$ on Lespedeza cuneata plant, whereas the number of eggs was $12.7{\pm}4.5$ on Cassia obtusifolia plant. Moreover, the eggs hatched within $5.1{\pm}0.9$ days from the day of oviposition and procent of egg hatchability was 53.7% on host plant. The headwidth of each developmental larval stage were $0.36{\pm}0.02$(1st), $0.61{\pm}0.02$(2nd), $0.93{\pm}0.05$(3rd), $1.46{\pm}0.08$(4th), $2.25{\pm}0.11$(5th). The larval period was $12.1{\pm}0.9$ days under high temperature, long day condition($25^{\circ}C$, 16L : 8D), showing 81.0% pupal ratio. The pupal period was $6.9{\pm}0.7$ days, and the emergence rate was 79.6%. Based on above experiment, artificial rearing system of common grass yellow butterfly, Eurema hecabe was completed in indoor condition.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.6
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• pp.447-453
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• 2007

With a broad objective for the development of microbial based fertilizers, a total of 373 strains were isolated from rhizoplane and rhizosphere of pepper, tomato, lettuce, pasture, and grass. The efficacy of the isolates to augument overall plant growth was evaluated. After screening for their plant growth promotion and antagonistic properties in vitro efficient strains were further selected. The most efficient strains was characterized by 16S rRNA gene sequences and biochemical techniques and was designated as Bacillus subtilis S37-2. The strains facilitated plant growth and inhibited the plant phathogenic fungi such as Fusarium oxysporum (KACC 40037, Rhizoctonia solani (KACC 40140), and Sclerotinia sclerotiorum (KACC 40457). Pot based bioassay using lettuce as test plant was conducted by inoculating suspension ($10^5$ to $10^8cells\;mL^{-1}$) of B. subtilis S37-2 to the rhizosphere of lettuce cultivated in soil pots. Compared with non-inoculated pots, marked increase in leaf (42.3%) and root mass (48.7%) was observed in the inoculation group where the 50ml of cell mixture ($8.7{\times}10^8cells\;ml^{-1}$) was applied to the rhizosphere of letuce either once or twice. Antagonistic effects of B. subtilis S37-2 strain on S. sclerotiorum (KACC 40457) were tested. All the tested lettuce plants perished after 9 days in treatment containing only S. sclerotiorum, but only 17% of lettuce was perished in the inoculation plot. B. subtilis grew well in the TSB culture medium. The isolates grew better in yeast extracts than peptone and tryptone as nitrogen source. The growth rate was 2~4 times greater at $37^{\circ}C$ as compared with $30^{\circ}C$ incubation temperature. B. subitlis S37-2 produced $0.1{\mu}g\;ml^{-1}$ of IAA (indole 3-acetic acid) in the TSB medium containing L-tryptophan($20mg\;L^{-1}$) in 24 hours.

• Journal of The Korean Association For Science Education
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• v.41 no.6
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• pp.471-481
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• 2021

The importance of science education for cultivating the competencies required by an intelligent information society is gradually being strengthened. The government's roles and responsibilities for science education are stipulated by laws and policies in Korea. In order to systematically support science education, continuous monitoring of related policies is essential. This study aims to develop indicators that can be used to systematically and continuously monitor the national policies on science education in Korea. To achieve this goal, we first derive the framework for the indicators that has two dimensions (learner and science education context) and three categories (input, process, and outcome) from literature reviews. In order to derive the components and subcomponents of the indicators, the contents of science education-related indicators developed in Korea or abroad were reviewed. In order to verify the suitability and validity of the framework and components of the initial indicators, a two-round Delphi method was conducted with 25 expert participants with five different professions in science education. Finally, three components of the 'input' category (student characteristics, teacher characteristics, and educational infrastructure), three components of the 'process' category (science curriculum implementation, science educational contents and programs implementation, and teacher professional development program implementation), and five components of the 'outcome' category (science competency, participation and action, affective achievement, cognitive achievement, and satisfaction) were derived. An instrument to collect data from students, teachers, and institutions was developed based on the components and subcomponents, and content validity and internal consistency of the instrument were analyzed. Korea's Science Education Indicators developed in this study can comprehensively measure the current status of science education and is expected to contribute to a more efficient and effective science education policy planning and implementation.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.14 no.5
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• pp.394-402
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• 2021

The entry of an aging society and the extension of human life expectancy, the increasing interest in women's social advancement and men's appearance, and the natural interest in K-culture through media media, while receiving worldwide attention, Focus on K-Bueaty. Recently, looking at the occupation of the medical tourism field, in the case of aesthetic medicine tourism such as molding and dermatology, it has gained popularity not only in Asia such as China and Japan, but also in North America and Europe. The first external confirmation of human aging is the wrinkles on the skin of the face. Clean, wrinkle-free, elastic and healthy skin is a desire of most people. Skin condition and condition such as focused ultrasonic stimulation (HIFU: High Intensity Focused Utrasound) and low frequency, high frequency (RF: Radio Frequency), galvanic therapy using microcurrent, cryotherapy using rapid cooling, etc. Depending on the method of management, the effect of the treatment differs depending on the output and the stimulation site, etc., even in the treatment of medical equipment and beauty equipment using the same mechanism. In this research, in order to develop invasive high-frequency dermatological devices using a large number of beauty medical devices and microneedles of beauty devices, the international standards IEC 60601-2 (standards for individual medical devices) and MFDS (Ministry of) We designed and developed a high-frequency output device in compliance with the high-frequency stimulation standard announced in the Food and Drug Safety (Ministry of Food and Drug Safety). The circuit design consists of an amplifier (AMP: Amplifier) using Class-A Topology and a power supply device using Half-Bridge Topology. As a result of measuring the developed high-frequency output device, an average efficiency of 63.86% was obtained, and the maximum output was measured at 116.7W and 50.67dBm.

• The Journal of Korean Academy of Sensory Integration
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• v.19 no.2
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• pp.12-25
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• 2021

Objective : This study explored the effects of family-centered coaching using a sensory integration-based approach on the levels of performance and satisfaction for children with autism spectrum disorder (ASD). Methods : From April 16, 2020 to August 6, 2020, participants included 10 children with ASD, between the ages of three to six who met the inclusion criteria, and their guardians. I used the Canadian Occupational Performance Measure (COPM) to evaluate the children's levels of performance and satisfaction and the Goal Attainment Scaling (GAS) to evaluate their occupational performance. The experimental group (n=5) continued the sensory integration therapy while receiving their personalized family-centered coaching training for 60 minutes per week. This continued for four weeks via home visits and video calls. The control group (n=5) also continued to receive the sensory integration therapy while receiving sensory integration-based general counseling in relation to activity objectives. Results : Statistically significant differences were found in the scores of COPM performance and satisfaction and the GAS scores between the experimental group and the control group, before and after the intervention (p<.05). Statistically significant differences were found in score changes in COPM and GAS, between the two groups (p<.05). Cohen's d also showed a big effect size on the scores of COPM satisfaction (d=2.768) and the GAS scores (d=2.786). Conclusion : This study demonstrated that the sensory integration-based, family-centered coaching had more positive effects on the level of performance and satisfaction of children with ASD, than general counseling.

• Korean Journal of Remote Sensing
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• v.37 no.6_2
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• pp.1859-1867
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• 2021

This study investigated seasonal characteristics of the particulate matter (PM) in the atmosphere and rainwater quality in Busan, South Korea, and evaluated the seasonal effect of PM₁₀ concentration in the atmosphere on the rainwater quality using multivariate statistical analysis. The concentration of PM in the atmosphere and meteorological observations(daily precipitation amount and rainfall intensity) are obtained from automatic weather systems (AWS) by the Korea Meteorological Administration (KMA) from March 2020 to August 2020. Rainwater samples (n = 216, 13 rain events) were continuously collected from the beginning of the precipitation using the rainwater collecting device at Pukyong National University. The samples were analyzed for pH, EC (electrical conductivity), water-soluble cations(Na⁺, Mg²⁺, K⁺, Ca²⁺, and NH₄⁺), and anions(Cl^-, NO₃^-, and SO₄^2-). The concentration of PM₁₀ in the atmosphere was steadily measured before and after the precipitation with a custom-built PM sensor node. The measured data were analyzed using principal component analysis (PCA) and Pearson correlation analysis to identify relationships between the concentration of PM₁₀ in the atmosphere and rainwater quality. In spring, the daily average concentration of PM₁₀ (34.11 ㎍/m³) and PM_2.5 (19.23 ㎍/m³) in the atmosphere were relatively high, while the value of daily precipitation amount and rainfall intensity were relatively low. In addition, the concentration of PM₁₀ in the atmosphere showed a significant positive correlation with the concentration of water-soluble ions (r = 0.99) and EC (r = 0.95) and a negative correlation with the pH (r = -0.84) of rainwater samples. In summer, the daily average concentration of PM₁₀ (27.79 ㎍/m³) and PM_2.5 (17.41 ㎍/m³) in the atmosphere were relatively low, and the maximum rainfall intensity was 81.6 mm/h, recording a large amount of rain for a long time. The results indicated that there was no statistically significant correlation between the concentration of PM₁₀ in the atmosphere and rainwater quality in summer.

• Korean journal of applied entomology
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• v.60 no.4
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• pp.403-415
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• 2021

Seasonal development of Parthenolecanium corni was observed from 4 Jun. 2019 (nymph) - 25 Jun. 2020 (1^st Gen. nymph) in blueberry shrub in Sacheon city, Gyeongsangnam-do. To investigate their development, more than 5 twigs sprouted in 2018 were taken from the farm nearly weekly basis. The development of each scale were examined under the stereomicroscope and chemical control was conducted in the blueberry shrub with available three insecticides. The results on the development period and Centigrade Degree-Days accumulation (DDC) obtained are as follows: egg-laying period (peak): 12 -26 May 2020 (24 May)(DDC, 110.0-188.5 (173.6)); egg-hatching period (peak): 9 - 23 June 2020 (19 June)(DDC, 325.2-480.8(435.6); egg period: 26 days; nymph movement from overwintered adult to new leaves 16-25 June 2020 (DDC, 410,5-500.4); nymph movement from leaf to twig (peak) to become adult: 4-18 Feb. 2020 (8 Feb.). Eggs no. /adult (range): 956.8 ± 73.4 (13 - 3497). Size (mm) of egg, 0.29 ± 0.020(L), 0.15 ± 0.013(W); of egg-hatched nymph, 0.35 ± 0.018(L), 0.18 ± 0.007(W), 0.09 ± 0.007(eye distance); and of adult, 4.30 ± 0.893(L), 2.64 ± 0.520(W). The egg-hatched nymphs from the overwintered adult moved to the backside leaf of new shoot in which they found about 95% until leaf is falling by early February in next year. They overwintered as 2^nd instar and occurred univoltine. For the control of the 1^st instar crawler, three insecticides treated on 16 and 30 July at the registered dose for Ceroplastes japonicus. Acetamiprid 8WP showed 96.9% mortality at 21 days after 1^st treatment.