• 한국지하수토양환경학회지:지하수토양환경
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• 제16권5호
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• pp.9-17
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• 2011

Positive effect of multiple-PGPR (Plan Growth Promoting Rhizobacteria), isolated from heavy metal contaminated soil, on the germination of Barnyard grass (Echinochloa crus-galli var. frumentacea) was quantitatively estimated in 5 heavy metal (Cd, As, Ni, Cu, and Pb) contaminated liquid medium. The $EC_{50}$ value for respective heavy metal was estimated by TSK (Trimmed Speraman-Karber) model based on germination rate. The results showed overall increase in $EC_{50}$ with PGPR inoculation. The $EC_{50}$ value increased 1.4% from 96.0 mg/L (control) to 97.4 mg/L (PGPR-treated) in As contaminated medium. In Ni contaminated medium, the $EC_{50}$ value increased 31.9% from 148.0 mg/L (control) to 195.2 mg/L (PGPR-treated), while the $EC_{50}$ showed 4.8% increase from 63.4 mg/L (control) to 66.5 mg/L (PGPR-treated) in Cu medium. Overall seedling growth was stronger in the PGPR treated seeds than that in the control, but positive effect on seedling growth was not conspicuous. At effective concentration of 100 mg/L, the average seedling length of the PGPR treatment in As, Cd, Cu, and Ni medium, respectively, was 1.13, 0.14, 0.40, and 0.06 cm longer than that in the control. However, the increase of seedling growth was statistically insignificant (p < 0.05). These results suggest that inoculation of the isolated-PGPR exerts positive effects on seed germination by reducing heavy metal toxicity and can be an effective tool for application of phytoremediation on heavy metal contaminated soils.

• 식물조직배양학회지
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• 제22권4호
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• pp.212-216
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• 1995

조직배양을 이용하여 시클라멘의 급속증식체계를 확립하기 위한 기초실험으로 자엽과 엽병을 auxin류와 cytokinin류가 혼용처리된 MS배지에 배양한 후 캘러스 발생 및 기관 재분화에 미치는 치상절편, 부위별, 생장조절제의 효과를 조사하였다. 절편부위별 효과는 자엽조직이 엽병조직보다 캘러스 및 캘러스로부터 shoot 분화에 좋은 반응을 보였다. 2,4-D와 kinetin 혼용처리구에서 자엽은 전혀 반응이 없었고 엽병절편에서는 2,4-D와 kinetin이 1.0 mg/L씩 혼용배지에서만 캘러스로부터 shoot가 재분화되었다. NAA와 BA 혼용배지의 경우 자엽절편에서는 모든 배지에서 캘러스가 유도되었으며 shoot 재분화는 0.2 mg/L NAA와 0.5 mg/L BA 혼용 배지에서 가장 양호하였고, 엽병조직은 0.2mg/L NAA와 2.0 mg/L BA 혼용배지에서 다수의 shoot가 재분화되어 가장 효과적이었다. Shoot로부터 발근에 적합한 NAA와 IAA의 효과를 조사하였던 바 NAA가 IAA보다 뿌리발생에 양호하였고 특히 1.0 mg/L NAA에서 다수의 뿌리가 발생되어 효과적이었다.

• 품질경영학회지
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• 제52권1호
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• pp.149-172
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• 2024

Purpose: By empirically analyzing factors that affect the intention to introduce RPA, we aim to increase understanding of RPA introduction in small and medium-sized businesses and contribute to establishing an effective introduction strategy. The aim is to improve the company's productivity, reduce costs, and strengthen its competitiveness. It also provides policy recommendations for the introduction of RPA. Methods: A survey was conducted to examine whether the technical, organizational, and environmental factors of the TOE framework had an impact on the intention to adopt RPA. We also used stepwise regression analysis to determine whether firm size moderates this relationship. Results: Technical factors, organizational factors, and environmental factors were all found to have a significant impact on small and medium-sized enterprises' intention to adopt RPA. It was confirmed that company size has a moderating effect affecting the intention to adopt RPA. In particular, customer pressure, relative advantage, competitive pressure, age, government support, and the perceived ease of use of RPA was a key determinant of its adoption by small and medium-sized enterprises. Conclusion: This suggests that small and medium-sized businesses should comprehensively consider technical, organizational, and environmental factors when introducing RPA. It is expected to increase understanding of RPA introduction in small and medium-sized businesses, contribute to establishing effective introduction strategies, and contribute to improving company productivity, reducing costs, and strengthening competitiveness.

• KIEAE Journal
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• 제15권3호
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• pp.93-99
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• 2015

Purpose: Various studies on the soil-based green roof systems have been conducted, and a lot of green roof systems were developed. A growing medium board is one of them which was developed for better application and maintenance, however the effect and performance of this material need to be verified. On this background, the purpose of this study is to prove cooling load reduction of green roof by monitoring experiment on the full-scale mock-ups. Method: To do this, Solid growing medium boards were installed on the mock-ups, and indoor temperature and humidity were monitored and analyzed. Result: As a results, the green roof with solid growing medium board were verified effective for controlling indoor temperature in summer.

• 한국자원식물학회지
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• 제7권2호
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• pp.171-175
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• 1994

The effects of medium, hormones, and PFP on the proliferation of red callus in leaf tissue cultures of Garden orach(Atriplex hortensis L.) was investigated. As a result,88% of leaf tissues formed eallus on MS nledium containing 2mg/$\ell$ 2,4-D. Fresh weight of callus was higher on MS medium than on Bsand NN media. It was also found that 2, 4-D was more effective than Dicamba and Picloram. The op-timum concentrations of hormones for callus proliferation depended on culture media. Isolated red cal-lus grew markedly both on MS medium supplemented with 1-2mg/$\ell$ 2, 4-D and Bs medium contain-ing 2-4111g/$\ell$ 2,4D. Callus proliferated on B5 and NN media containing Dicabma Img/$\ell$ as well as onthe same media containing 2mg/$\ell$ Picioram. The addition of PFP concentrations of 2, 5, and 40mg/ $\ell$rcspectiely to culture medium caused increase of callus fresh weight, especially under light condition.

• 한국미생물·생명공학회지
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• 제22권5호
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• pp.561-563
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• 1994

For the more effective isolation of soil actinomycetes, we have developed HHV (Hair hydrolysate-vitamin) agar medium, containing hair as the sole source of carbon and nitrogen. The HHV agar medium was superior to other media such as colloidal chintin agar, glycerol-arginine agar and starch-casein-nitrate agar, and HV (humic acid-vitamin) agar. The maximum effect of this medium has been shown in hair dry weight 0.4 g/l medium. Of each soil sample, the greatestest number of actinomycetes was isolated from the potato annual planted soil among the tested samp- les. The genus of actinomycetes isolated from the potato annual planted soil sample was identified such 5 group as Stretomyces, Micromonospora, Microbispora, Nocardia and Saccharopolyspora.

• Biotechnology and Bioprocess Engineering:BBE
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• 제5권5호
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• pp.350-354
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• 2000

The growth promotion of a Taxus brevifolia cell suspension culture was investigated using conditioning factors. The conditioning factors produced and secreted from cultured cells usually stimulate cell division and the production of secondary metabolites. Therefore, the effective incubation time for the optimal secretion of conditioning factors was firstly determined for the promotion of cell growth. Conditioned media obtained by cultivating for 2 and 5 days showed the promotion of initial cell growth during the early cell growth period. However, the positive effect of the conditioning factors on the initial cell growth did not continue because of the depletion of the medium nutrients. Accordingly, the addition of a carbon source to the conditioned medium prolonged the positive effect on the cell growth. The addition of sucrose to the conditioned medium resulted in the maximum cell density being reached 4 days earlier compared to the control group and an increased substrate yield.

• 한국식품저장유통학회지
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• 제7권1호
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• pp.63-67
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• 2000

Changes in the compressive strength of four typical corrugating mediums (K$_2$A, AS and S) as affected by relative humidity conditions were compared and their relative cost effectiveness was analysed. All mediums lost their compressive strength as relative humidity increased. at the relative humidity of 93% , As medium lost 58% of its initial strength while S medium did about 40%. Calculations of compress factor and compress factor by price indicated that $K_2$ medium was the most cost effective and maintained the highest compressive strength among the mediums tested. It was recommended that $K_2$ medium could be effectively used to make corrugated fiberboard especially for fresh agricultural product packaging .

• Steel and Composite Structures
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• 제23권6호
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• pp.623-631
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• 2017

Present paper deals with the temperature-dependent buckling analysis of sandwich nanocomposite plates resting on elastic medium subjected to magnetic field. The lamina layers are reinforced with carbon nanotubes (CNTs) as uniform and functionally graded (FG). The elastic medium is considered as orthotropic Pasternak foundation with considering the effects of thermal loading on the spring and shear constants of medium. Mixture rule is utilized for obtaining the effective material properties of each layer. Adopting the Reddy shear deformation plate theory, the governing equations are derived based on energy method and Hamilton's principle. The buckling load of the structure is calculated with the Navier's method for the simply supported sandwich nanocomposite plates. Parametric study is conducted on the combined effects of the volume percent and distribution types of the CNTs, temperature change, elastic medium, magnetic field and geometrical parameters of the plates on the buckling load of the sandwich structure. The results show that FGX distribution of the CNTs leads to higher stiffness and consequently higher buckling load. In addition, considering the magnetic field increases the buckling load of the sandwich nanocomposite plate.

• 에너지공학
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• 제28권1호
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• pp.30-36
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• 2019

군에서는 다양한 전술차량들을 개발하여 운용하고 있다. 그 중 중형전술차량은 기존 군용트럭을 대체하면서 병력수송에 적합한 차량으로 개발되어 보병부대의 전투력에 중요한 영향을 끼친다. 이런 중요한 무기체계인 중형전술차량에 연료 효율을 높이는 기술을 적용한다면 항속거리가 증가되어 효과적인 작전수행과 유류비를 감소시킬 수 있다. 본 연구에서는 연료 효율을 높이기 위해 오일 온도 제어 전략을 적용하여 중형전술차량의 항속거리를 향상시키기 위한 방안에 대해 연구하였다.