• Proceedings of the Korea Information Processing Society Conference
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• 2023.05a
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• pp.314-315
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• 2023

도시 나무는 환경적, 경제적, 사회적 혜택에 크게 기여하기 때문에 그 필요성이 널리 인식되어 왔다. 그러나 도시화와 도시 개발로 인해 녹지 공간이 부족해지면서 충분한 나무가 자라지 못하고 있다. 따라서 도시 녹지를 제공하기 위한 대안이 제시되고 있다. 그러한 방법 중 하나는 가로수를 대체할 수 있는 미세조류를 배양하기 위해 광생물반응기를 사용하는 것이다. 세르비아 국립대학교는 이를 위해 LIQUID 3 기술을 사용하여 새로운 광생물반응기 구조를 개발했다. 본 논문에서는 이 기술에 대한 연구와 국내 적용 가능성을 논의한다.

• The Korean Journal of Soil Zoology
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• v.1 no.2
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• pp.81-88
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• 1996

Entomopathogenic nematodes, Steinernema carpocapsae, was able to invade and kill the several lepidopteran pests including the beet armyworm, Spodeptera exigua Hubner, which was the most effective target host. The beet armyworms treated with the effective nematode concentrations were died within 48 hrs. The lethal effect of the nematode was varied among the developmental stages of the host. The fifth instar larvae of the beet armyworm was more vulnerable to the nematode than the third instar larvae. Pupae was, however, refractory to the nematode. All three bioessays (topical application, filter paper test, and soil treatment) showed the positive correlation between the number of the treated nematodes and the mortality of the host. Topical application was the most effective and fast-acting method so that it gave the lethal effect 2 days earlier than did filter paper test at the same number of the treated nematodes. Soil treatment required higher number of the nematodes to get the effective lethality than did filter paper test. The fifth instar larvae of the beet armyworm expressed the specific hemolymph proteins of 5 to 10 kDa in response to nematode infection.

• Journal of Science Education
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• v.40 no.3
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• pp.189-202
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• 2016

This study aimed to investigate pre-service science teachers' perceptions of significance and usefulness of evolution and genetics. To this end, 82 pre-service biology teachers and 159 non-biology science teachers answered the items to measure the perceptions of significance and usefulness of evolution and genetics. The validity and reliability were examined using Cronbach alpha, two-dimensional rating scale model Rasch analysis, and factor analysis. The finding illustrated that the test items met the benchmark to be valid and reliable test items. Second, pre-service teachers' perception of significance and usefulness of evolution was independent to that of genetics. The level of pre-service teachers' perception of significance and usefulness of evolution was lower than the level of genetics. Lastly, the levels of pre-service teachers' perceptions of significance and usefulness of evolution and genetics were not significantly different across academic years and majors (biology and non-biology). The findings of this study stressed the importance of teaching significance and usefulness of evolution and genetics in pre-service science teacher education program.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.396-396
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• 2022

생물전기화학적 혐기성소화(Bioelectrochemical anaerobic digestion; BEAD)는 소량의 전압공급을 통해 고농도 하·폐수의 효과적인 처리 및 에너지 회수가 가능한 처리방법으로, 기존 하·폐수처리공정(활성슬러지 및 그 변법)에서 벗어나기 위한 방법 중 하나로 연구되고 있지만, 내부저항 및 전극구조에 따른 물질전달저해로 인해 소규모 연구 위주로 진행되었다. 하지만 stainless steel(SS) 등 내부저항을 완화할 수 있는 전극재료 및 전극구조 개선 연구가 진행됨에 따라 BEAD 적용규모가 증가하는 추세이며, 본 연구에서는 100 L의 용량에서 전극재질 및 구조에 따른 적용적합성을 에너지효율 비교를 통해 평가하였다. 반응조는 비교를 위한 AD, 반응조 내부에 전극을 설치한 BEAD, 반응조 외부에 전극이 포함된 반응조를 추가한 ABEAD로 구성하였으며, AD 및 BEAD는 기계적 교반, ABEAD는 기계적 교반 및 펌프를 통한 bulk 용액 순환으로 물질전달이 이뤄졌다. 또한 BEAD는 탄소계 전극, ABEAD는 SS계 전극을 사용하였으며 두 반응조 모두 0.4 V의 전압을 공급하였다. 실험조건은 유효용량 100 L, 유기물부하율 3 kg/m³/d, HRT 20 days 및 중온소화(35℃)으로 운전하였다. 실험결과 AD, BEAD 및 ABEAD의 유기물제거율은 각각 평균 68.1 %, 68.9 %, 74.9 %로 전극 및 반응조의 분리를 통해 물질전달을 개선한 ABEAD에서 증가하였다. 에너지 생성량의 경우 AD에 비해 BEAD는 평균 229 kJ/d, ABEAD는 309 kJ/d가 추가 생성되었으며 유기물제거율이 높은 ABEAD에서 더 높은 에너지생산이 이뤄졌다. 마지막으로 전압공급으로 인한 에너지소비량은 BEAD는 평균 3.4 kJ/d, ABEAD는 평균 0.9 kJ/d로 전극의 낮은 생물적합성으로 인해 전극에서의 생화학반응이 적은 ABEAD가 에너지소비량이 낮았다. 따라서 본 연구에서는 SS 전극의 사용가능성 및 전극구조 개선에 따른 에너지효율성 향상을 확인할 수 있었으며, 추후 연구에 활용할 수 있을 것으로 기대된다.

• Journal of Korean Society of Forest Science
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• v.110 no.3
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• pp.393-405
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• 2021

With increasing anthropogenic emission sources, air pollutants are emerging as a severe environmental problem worldwide. Accordingly, the importance of landscape trees is emerging as a potential solution to reduce air pollutants, especially in urban areas. This study quantified and compared NO₂ and SO₂ reduction abilities of ten major landscape tree species and analyzed the relationship between reduction ability and physiological and morphological characteristics. The results showed NO₂ reduction per leaf area was greatest in Cornus officinalis (19.81 ± 3.84 ng cm^-2 hr^-1) and lowest in Pinus strobus (1.51 ± 0.81 ng cm^-2 hr^-1). In addition, NO₂ reduction by broadleaf species (14.72 ± 1.32 ng cm^-2 hr^-1) was 3.1-times greater than needleleaf species (4.68 ± 1.26 ng cm^-2hr^-1; P < 0.001). Further, SO₂ reduction per leaf area was greatest in Zelkova serrata (70.04 ± 7.74 ng cm^-2 hr^-1) and lowest in Pinus strobus (4.79 ± 1.02 ng cm^-2 hr^-1). Similarly, SO₂ reduction by broadleaf species (44.21 ± 5.01 ng cm^-2 hr^-1) was 3.9-times greater than needleleaf species (11.47 ± 3.03 ng cm^-2 hr^-1; P < 0.001). Correlation analysis revealed differences in NO₂ reduction was best explained by chlorophyll b content (R² = 0.671, P = 0.003) and SO₂ reduction was best described by SLA and length of margin per leaf area (R² = 0.456, P = 0.032 and R² = 0.437, P = 0.001, R² = 0.872, P < 0.001, respectively). In summary, the ability of trees to reduce air pollutants was related to photosynthesis, evapotranspiration, stomatal conductance, and leaf thickness. These findings highlight effective reduction of air pollutants by landscaping trees requires comprehensively analyzing physiological and morphological species characteristics.

• Food Engineering Progress
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• v.13 no.3
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• pp.183-189
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• 2009

Lactobacillus sakei B2-16 producing high level of $\gamma$-amino butyric acid (GABA) was previously isolated from Korean traditional fermented food, Kimchi. L. sakei B2-16 converted 99.3% of mono sodium glutamate (MSG) to GABA in Lactobacilli MRS broth supplemented with 1% MSG. In order to enhance the production of GABA by L. sakei B2-16, growth parameters such as media components and concentrations of major components were evaluated. The maximum GABA concentration was obtained by a modified rice germ extract broth containing 4%(w/v) sucrose and 1%(w/v) yeast extract. L. sakei B2-16 converted 100% of MSG to GABA in modified rice germ extract broth supplemented with 7% MSG.

• Korean Journal of Plant Resources
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• v.34 no.5
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• pp.470-477
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• 2021

Amsonia ellipotica (Thumb.) Roem. & Schult. has less than 10 native places nationwide and is evaluated as an endangered species (EN) on the Korean Red List, so systematic breeding and cultivation methods are required. This study was carried out to establish an effective method for seedling production in A. elliopotica that can be developed as a genetic resource conservation and new ornamental material. This experiment was performed by varying the seedling production container (72, 105 and 128 cell trays), number of seeds sown in a cell (1, 2, and 4 per cell), soil type [horticultural soil and neutralized peat-moss: perlite mixed in 3:1, 4:1 (v:v)], additional fertilizer concentrations (0, 250, 500 and 1000 mg/L) and shading degrees (0, 55 and 75%). As a result of the study, growth increased with the increased in measuring capacity per cell of sowing container. According to number of seeding growth, sowing one seed per cell was the best. Seedling growth increased as the treatment concentrations increased, higher growth was in 1000 mg/L. On the other hand, during the shading treatment, growth significantly decreased regardless of shading degrees.

• Clean Technology
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• v.27 no.3
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• pp.255-260
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• 2021

A drawback in the CO₂ capture process using an aqueous amine solution is the high energy requirement for the regeneration process. In order to overcome this disadvantage, this study investigated CO₂ capture characteristics using a biphasic absorbent in which isopropanol (IPA) was introduced into an aqueous solution of diethylenetriamine (DETA). When the IPA composition exceeded 20 wt% in 20 wt% DETA aqueous solution, the absorbent phase was liquid-liquid separated into a CO₂-rich phase and a CO₂-lean phase because of the low solubility of the salt formed by the reaction of CO₂ with DETA in isopropanol. When the isopropanol composition in the DETA aqueous solution increased, the phase volume ratio of the CO₂-rich phase to the volume of the CO₂-lean phase increased; and, accordingly, the CO₂ in the CO₂-rich phase was more concentrated. The results of absorbing CO₂ in a packed tower using 20 wt% DETA + IPA + water absorbent confirmed that both the CO₂ absorption capacity and the absorption rate were higher than that of the 20 wt% DETA aqueous solution. When a biphasic absorbent composed of DETA + IPA + water is applied to CO₂ capture, it can be expected to concentrate CO₂ because of phase separation and thereby reduce regeneration energy owing to volume reduction of the CO₂-rich phase.

• Food Engineering Progress
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• v.15 no.2
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• pp.182-187
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• 2011

A proteolytic lactic acid bacterium was isolated from Korean traditional fermented foods. The isolate BV-26, which had a protease activity (24 U/mg-crude protein), was identified as Lactobacillus plantarum by the API 50CHL kit and 16S rDNA analysis (99.9% of homology), and named as L. plantarum BV-26. Cell growth and protease activity of L. plantarum BV-26 was determined in MRS broth using 5L jar fermentor at $30^{\circ}C$. The maximum growth of L. plantarum BV-26 was reached at 18 hr in MRS broth, while protease activity of BV-26 was detectable at 12 hr and the highest activity was obtained after 16 hr cultivation. Therefore, we expect that the proteolytic lactic acid bacteria, L. plantarum BV-26, may be used as a starter for the fermentation of animal feed. Especially, the fermentation of soybean meal with the strain can be applied for improving feed utilization.

• Applied Chemistry for Engineering
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• v.22 no.6
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• pp.599-604
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• 2011

In this study, we investigated the efficacy of ${\beta}$-cyclodextrin (${\beta}CD$) hydrorogel containing silk fibroin (SF) on healing burnt wound. Tosyl ${\beta}CD$ was conjugated to polyethyleneimine (PEI) using epichlorohydrin (EPI) as a cross-linker. The ${\beta}CD/PEI/SF$ hydrogel was applied on the back of mouse and then the efficacy of hydrogel was compared with both positive control group and negative control group. There was no wound healing efficacy showed neither in the drug loaded ${\beta}CD/PEI/SF$ hydrogel group nor in the drug unloaded ${\beta}CD/PEI/SF$ hydrogel group. On the other hand, in the positive control group, a significant reduction of the wound size after the usage of OTC hydrorogel was obtained. The burn-healing histological result showed a similar phenomenon. After hematoxylin-eosin staining the skin induced by burning, and the epithelial growth observed in the dermis, the efficacy of ${\beta}CD/PEI/SF$ hydrogel in healing burnt wound could not be clearly identified.