• 한국재난정보학회 논문집
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• 제6권1호
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• pp.28-43
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• 2010

This paper presents the field applications of polymer-modified warm asphalt mixture which can reduce the temperature during the production and field constructions. The amount of fuel consumptions and $CO_2$ diffusions can be reduced by much using the polymer-modified warm asphalt mixture instead of the conventional polymer-modified asphalt mixture. According to the research results, the polymer-modified warm asphalt mixture can be utilized without additional temperature increasement and performance sacrifice during the plant production and public service, respectively. As a result, it is considered that the application of the polymer-modified warm asphalt mixture has the potential of convenience in constructions management and reducing the environmental damages.

• 한국안전학회지
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• 제28권6호
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• pp.6-10
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• 2013

A numerical reproducibility of the backdraft phenomena in a compartment was investigated. The prediction performance of two combustion models, the mixture fraction and finite chemistry models, were tested for the backdraft phenomena using the FDS code developed by the NIST. The mixture fraction model could not predict the flame propagation in a fuel-air mixture as well as the backdraft phenomena. However, the finite chemistry model predicted the flame propagation in the mixture inside a tube reasonably. In addition, the finite chemistry model predicted well the backdraft phenomena in a compartment qualitatively. The flame propagation inside the compartment, fuel and oxygen distribution and explosive fire ball behavior were well simulated with the finite chemistry model. It showed that the FDS adopted with the finite chemistry model can be an effective simulation tool for the investigation of backdraft in a compartment.

• Mycobiology
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• 제34권4호
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• pp.191-195
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• 2006

This study was conducted to investigate the different effects of ectomycorrhizal fungal (ECMF) species on the growth of seedlings of Pinus densiflora, and the effects of ECMF diversity on plant productivity. A total of five species of ECMF were isolated from root tips of pine seedlings collected from Mt. Songni and used as inocula. Pots containing pine seedlings were inoculated with either a single ECMF species or a mixture of five ECMF species. All of the seedlings formed ECM on their roots except for the control plants. The pine seedlings' growth responses varied by the different ECMF species. Also, pine seedlings inoculated with a mixture of five ECMF species showed the highest growth response. The results of the study suggest that the colonization of diverse species of ECMF will increase plant productivity, and the selection of suitable ECMF species could be an important factor for plant growth.

• 식물병연구
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• 제14권3호
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• pp.182-186
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• 2008

최근 벼 유기재배에서 식물병 방제를 위한 친환경농자재가 없는 것이 주요한 제한요인으로 제기되고 있다. 식물병 방제를 위해 보르도액은 효과적인 예방 농자재로 사용되어져 왔다. 본 연구에서는 석회보르도액의 벼 잎도열병 방제효과를 조사하였다. 온실검정결과 6-6식 석회보르도액 100배액을 발병초에 살포한 결과 70.8%의 방제효과를 나타냈다. 포장검정에서는 4-8식과 6-6식 석회보르도액을 살포한 결과 잎도열병에 대한 방제효과가 73.6%와 71%를 나타냈다. 각각 조제한 석회보르도액의 30배와 50배 처리농도에서는 약해가 발생하였으나, 200배액 살포농도에서는 약해가 나타나지 않았다. 따라서 유기재배 및 무농약 재배포장에서 벼 잎도열병 방제를 위한 효과적인 친환경농자재로서 석회보르도액이 활용될 수 있을 것으로 사료된다.

• 한국환경과학회지
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• 제23권2호
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• pp.303-312
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• 2014

As for chemical characteristics of cultivated media waste, the total content of nitrogen, phosphoric acid, and potassium was 6.93%; organic matter content was 67.78%; pH and EC were 7.20 and 1.46 ds/m, respectively. Organic acids identified during stabilization included citric acid, oxalic acid, fumaric acid, and acetic acid, which was highest. During the stabilization of cultivated media waste, temperature decreased and pH increased on the 15th day, and the germination index was 88 after the period, indicating that at least 15 days of stabilization is needed when cultivated media waste is used for growth material of crop. As for germination characteristics, when the mixture rate of cultivated media waste was 20% and under, germination of cucumber and oriental melon was favorable without difference compared to the control plots. For lettuce and Chinese cabbage, no statistically significant difference was found when the rate was 10% and under compared to the control plots. As for seedling quality after 20 days of sowing, cucumber, oriental melon, and Chinese cabbage showed favorable growth only when the mixture rate of cultivated media waste was 10% and under; lettuce showed lower growth characteristics regardless of mixture rate when compared to the control plots. Cultivated media waste may be significantly useful for cucumber and oriental melon, but not for Chinese cabbage and lettuce.

• 생물환경조절학회지
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• 제16권2호
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• pp.142-145
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• 2007

몇 수종을 대상으로 한 용기 양묘에서 폐암면 혼합 배지 이용 시 폐암면과 다른 배지의 혼합 비율에 따른 생육 특성을 조사하였다. 폐암면 혼합 비율에 따른 소나무의 생육 특성에서 생체중, 건물중 및 수고는 50% 와 70% 혼합배지에서 기장 좋았지만 원줄기 직경은 차이를 나타내지 않았다. 비자나무에서 생체중과 수고는 70% 혼합배지에서 가장 많이 증가하였고 원줄기 직경과 신초수는 50% 와 70% 혼합배지에서 많이 증가하였다. 상수리나무에서 생체중, 수고 및 원줄기 직경은 50%와 70% 혼합배 지에서 좋았고, 건물중은 혼합배지와 대조구간 차이를 나타났으나 혼합 비율간에는 차이를 나타내지 않았다. 잎의 엽록소 함량도 70% 혼합배지에서 높게 나타났으며 이에 광합성도 가장 활발하였다. 들메나무에서 생체 중은 70% 혼합배지에서 월등히 많이 증가하였지만, 수고와 원줄기 직경은 폐암면 혼합배지와 대조구 간 차이만 나타나고 혼합 비율간에는 차이를 나타내지 않았다. 잎의 엽록소 함량은 처리 간 차이를 나타내지 않았지만 혼합 배지에서 다소 높은 경향을 나타내었지만, 광합성은 70% 혼합배지에서 아주 활발하였다.

• Plant Biotechnology Reports
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• 제5권1호
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• pp.1-7
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• 2011

Secondary walls have recently drawn research interest as a primary source of sugars for liquid biofuel production. Secondary walls are composed of a complex mixture of the structural polymers cellulose, hemicellulose, and lignin. A matrix of hemicellulose and lignin surrounds the cellulose component of the plant's cell wall in order to protect the cell from enzymatic attacks. Such resistance, along with the variability seen in the proportions of the major components of the mixture, presents process design and operating challenges to the bioconversion of lignocellulosic biomass to fuel. Expanding bioenergy production to the commercial scale will require a significant improvement in the growth of feedstock as well as in its quality. Plant biotechnology offers an efficient means to create "targeted" changes in the chemical and physical properties of the resulting biomass through pathway-specific manipulation of metabolisms. The successful use of the genetic engineering approach largely depends on the development of two enabling tools: (1) the discovery of regulatory genes involved in key pathways that determine the quantity and quality of the biomass, and (2) utility promoters that can drive the expression of the introduced genes in a highly controlled manner spatially and/or temporally. In this review, we summarize the current understanding of the transcriptional regulatory network that controls secondary wall biosynthesis and discuss experimental approaches to developing-xylem-specific utility promoters.

• Journal of Plant Biotechnology
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• 제50권
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• pp.108-114
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• 2023

In vitro conservation is one of the most effective strategies for rare plant protection, especially for orchid species. To maximize the success rates of in vitro explant establishment (stage I) in conservation programs, the application of tissue culture additives such as Plant Preservative Mixture^TM (PPM^TM) should be emphasized. In this study, we used Dendrobium thyrsiflorum Rchb.f. (1875) seeds and seedlings as a model for the evaluation of PPM^TM's phytotoxicity in the meristematic tissues of epiphytic orchids. PPM^TM had no observable inhibitory effect on protocorm, shoot, or root development when it was supplemented at 0.1%. PPM^TM supplementation caused adverse effects on D. thyrsiflorum explants at concentrations > 0.2%. At high concentrations, young in vitro seedlings showed damage, especially at the root tissue level. Based on this model, supplementation of 0.1-0.2% PPM^TM to culture media was successfully implemented to establish in vitro cultures of other rare orchid species in our conservation program.

• 한국도로학회논문집
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• 제19권2호
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• pp.67-74
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• 2017

PURPOSES : The objective of this study is to ascertain the curing period of cementless cold central plant recycled asphalt base-layer, using mechanical analyses and specimen quality tests on the field. METHODS : Cold central plant recycled asphalt base-layer mixture was produced in the plant from reclaimed asphalt, natural aggregate, filler for the cold mix, and the modified emulsion AP using asphalt mix design and plant mix design. In order to examine the applicability of the curing period during the field test, the international standards for the possibility of core extraction and the degree of compaction and LFWD deflection were analyzed. Moreover, Marshall stability test, porosity test, and indirect tensile strength test were performed on the specimens of asphalt mix and plant mix design. RESULTS : The plant production process and compaction method of cementless cold central plant recycled asphalt base-layer were established, and the applicability of the optical moisture content for producing the mixture was verified through the field test. In addition, it was determined that the core extraction method of the conventional international curing standard was insufficient to ensure performance, and the LFWD test demonstrated that the deflection converges after a two-day curing. However, the back-calculation analysis reveals that a three-day curing is satisfactory, resulting in a general level of performance of dense asphalt base-layer. Moreover, from the result of the specimen quality test of the asphalt mix design and plant mix design according to the curing period, it was determined that the qualities satisfied both domestic and international standards, after a two-day curing. However, it was determined that the strength and stiffness after three-day curing are higher than those after a two-day curing by approximately 3.5 % and 20 %, respectively. CONCLUSIONS:A three-day curing period is proposed for the cementless cold central plant recycled asphalt base-layer; this curing period can be demonstrated to retain the modulus of asphalt-base layer in the field and ensure stable quality characteristics.

• 한국산학기술학회논문지
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• 제6권4호
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• pp.296-301
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• 2005

본 연구는 암비탈면 녹화시 음식물퇴비가 식생기반재료로 활용될 수 있는지에 대한 기초자료를 얻기 위해 실시되었다. 녹화용 식생으로 외래초종 Creeping red fescue(Festuca rubra), Perennial ryegrass(Lolium perenne) 2종을, 재래 초목본 쪽제비싸리(Amorpha fruticosa), 낭아초(Indigofera pseudo-tinctoria) 2종을 선정하여, 염분농도와 퇴비 사용량에 따른 종자별 발아특성 및 인공비탈면에서의 혼파실험을 통한 생육특성을 조사하였다. 염분농도에 따른 발아특성은 쪽제비싸리, 낭아초, Perennial ryegrass의 경우 $0.4\%$ 이상 NaCl 농도에서 발아율과 유아 및 유근길이가 급격히 감소하였으며, Creeping red fescue는 $0.2\%$ 이상 NaCl 농도에서 매우 급격한 생육저해가 일어났다. 퇴비 시용량에 따른 발아특성은 쪽제비싸리와 낭아초의 경우 모든 실험구에서 $45\%$ 내외의 발아를 보였으며, Perennial ryegrass는 퇴비시용량이 많을수록 초장의 성장이 증가하는 경향을 보였다. 피복률은 Mixture III가 $89.3\%$로 가장 높았으며, Mixture III > Mixture IV > Mixture II > Mixture I순이었다. Mixture I은 30일 후 $47.0\%$를 보였으나 45일 후에는 $64.1\%$로 높아졌다. 외래초종의 생육이 활발한 실험구 일수록 피복률이 높은 관계를 보였다.