• Title/Summary/Keyword: Culture efficiency

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Characterization of degradation of fish wastes using mixed microorganisms (복합미생물을 이용한 수산폐기물의 분해특성)

  • 정해윤;정해윤;김중균
    • Journal of Life Science
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    • v.11 no.1
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    • pp.76-82
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    • 2001
  • Fifteen species of microorganisms were isolate form the intestines of fishes, fish feed, and ferment. Eleven microorganisms except HY4, HY8, HY12, and HY13 were Gram-positive, and HY1, HY2, HY3, HY5, HY6, and HY7 produced lactic acid. The species of HY1, HY2, HY3, HY4, HY5, HY6, HY13, and HY14 showed some growth in the medium containing 1% of NaCl. Except HY6, HY7, HY8, HY12 and HY5, 10 isolates had proteolytic activity, whereas only HY13 and HY14 had lipase activity. From all the results four isolates (HY3, HY4, HY13 and HY14) were chosen for the degradation of fish wastes. There was no mutual inhibition among the microorganisms, and the optimum temperature and pH for the growth of the mixed culture were found to be 3 2$\^{C}$ and 7, respectively. Under the optimum growth conditions the maximum optical density and the maximum specific growth rate were estimated to be 2.35 and {TEX}$0.46h^{-1}${/TEX}, respectively. Major microorganisms in the mixed culture at the log-phase were HY3 and HY4, which occupied 70%. The degrading efficiency of fish waste by the mixed microorganisms was 2.3 times higher, compared to control. The total amount of free amino acids in the degraded products from fish wastes was 39g/100g protein and little odor was produced by the mixed microorganisms after 48 hours.

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Use of Androgenesis in Haploid Breeding

  • Yi, Gihwan;Kim, Kyung-Min;Sohn, Jae-Keun
    • Current Research on Agriculture and Life Sciences
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    • v.31 no.2
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    • pp.75-82
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    • 2013
  • Haploids are plants with a gametophytic number of chromosomes in their sporophytes. Androgenesis occurs from asymmetric division of pollen grains into generative cells and vegetative cells, followed by re-entry of the vegetative cell during S-phase, which causes microspores progress into G2/M transition in culture. One of the most interesting features of haploids is the possibility to produce doubled haploid (DH) individuals. Doubled haploidy is extremely useful to plant breeders because it enables shortened breeding periods and efficiency in selection of useful recessive agronomic traits. Doubled-haploid technology is not only applicable to breeding, but also to transformation programs of desired genes. In addition to practical breeding programs, DH lines provide useful materials of fundamental genetics including exploitation of QTLs and genes conferred with various agronomic traits by establishing DH populations. This paper provides historical overviews on androgenesis and describes several mechanisms associated with pollen embryogenesis, including mode of actions in pollen embryogenesis, mechanisms of chromosome doubling and factors affecting androgenesis. We also discuss recent progress in application of haploids to breeding, genes associated with in vitro response and drawbacks to anther culture for application of doubled haploids in crop breeding.

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The Case Study on the Performance between SCM Adopted Textile.Fashion Firms and Unadopted Firms in a Viewpoint of BSC (BSC 관점에서 SCM 도입 섬유.패션 기업과 미도입 기업의 성과에 대한 사례 연구)

  • Shin, Sang-Moo;Yoon, Jae-Chun
    • The Research Journal of the Costume Culture
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    • v.17 no.1
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    • pp.177-188
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    • 2009
  • SCM as the important marketing strategy enhance the firm's efficiency and compatibility in global market environment such as global outsourcing. Firms adopted SCM realized the need to evaluate precisely the performance of SCM. In spite of importance of SCM, there was not much intention and research to measure SCM performance in textile fashion industry. Therefore, the purpose of this case study was to measure performance of supply chain management in textile fashion business using BSC(Balanced Score Card) to measure not only financial perspective but also non-financial perspectives such as customer perspective, internal business perspectives, financial perspective, and innovation & learning perspective. The questionnaire developed by the reviews of the literature was adopted for this study. The results of this study showed that SCM performance was enhanced from the point of customer perspective(cost, quality, time, service), financial perspective(cash cycle time, inventory turn over, inventory obsolescence, return on asset, return on investment, capacity utilization), and innovation & learning perspective(cost for human resource management, service for human resources). But there was same performance level regarding internal business perspective(lead time, cost for manufacturing process, product quality control, productive flexibility for time, quantity, and variety). Therefore, we should keep close relationship and two way communication among supply chain members to promote better SCM performance.

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Influence on overfitting and reliability due to change in training data

  • Kim, Sung-Hyeock;Oh, Sang-Jin;Yoon, Geun-Young;Jung, Yong-Gyu;Kang, Min-Soo
    • International Journal of Advanced Culture Technology
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    • v.5 no.2
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    • pp.82-89
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    • 2017
  • The range of problems that can be handled by the activation of big data and the development of hardware has been rapidly expanded and machine learning such as deep learning has become a very versatile technology. In this paper, mnist data set is used as experimental data, and the Cross Entropy function is used as a loss model for evaluating the efficiency of machine learning, and the value of the loss function in the steepest descent method is We applied the GradientDescentOptimize algorithm to minimize and updated weight and bias via backpropagation. In this way we analyze optimal reliability value corresponding to the number of exercises and optimal reliability value without overfitting. And comparing the overfitting time according to the number of data changes based on the number of training times, when the training frequency was 1110 times, we obtained the result of 92%, which is the optimal reliability value without overfitting.

The Efficacy of Zoom Technology as an Educational Tool for English Reading Comprehension Achievement in EFL Classroom

  • Kim, HyeJeong
    • International Journal of Advanced Culture Technology
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    • v.8 no.3
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    • pp.198-205
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    • 2020
  • The purpose of this study is to investigate the effect of real-time remote video instruction using zoom on learners' English reading achievement. The study also sought to identify the efficiency of zoom video lectures and consider supplementing them by surveying learners' opinions and satisfaction regarding zoom video lectures. To this end, control and experimental groups were set up, and two achievement tests and a questionnaire were conducted. The study's results demonstrated that zoom video lectures have a positive effect on learners' English reading achievement. The questionnaire found that learners are satisfied with zoom video lectures for the following reasons: 'increased interest in and motivation towards learning', 'self-directed learning', 'active interaction', 'ease of access', 'ease of information retrieval'. At the same time, the questionnaire also found that some learners are dissatisfied with zoom video lectures due to 'mechanical errors or defects', 'poor audio quality', and 'the need to add customized functions for efficient classes'. In practice, zoom video lectures must be supplemented with automatic attendance processing, convenient data upload and download, and more efficient video screen management. Given the recent increase in online classes, we, as instructors, must develop teaching activities and/or strategies for video lectures that can encourage active participation by learners.

Study on Priorities of Regional Climate Change Policy (기후변화정책 우선순위 연구)

  • Hwang, Eunjoo;Choi, Yun Hyeok;Kim, Jong Dae
    • Journal of Environmental Science International
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    • v.25 no.4
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    • pp.589-601
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    • 2016
  • This study aims to analyze the priority of regional climate change policy utilizing AHP (analytic hierarchy process) at the area of Metropolitan City of Incheon. It derives four factors at first hierarchical level, at which level the analysis of pair-wise comparison indicates that industrial sector, energy sector, climate change response, and green culture policy are considered important in that order. It also ends up with sixteen factors at second level. The result of comparison analysis between all factors reveals that investment promotion in green technology R&D is considered the most significant factor of all, followed by establishment of green enterprise support system, electricity-efficiency enhancement support project and build-up of green culture policy governance. The result implies that diverse promotional policies have to incorporate business, institutional, and cultural aspects for sustainable climate change policy of regions. The contribution of this study is that it highlights the need to include regional characteristics in deciding priority among policy options for them to be effective.

Adaptive method for selecting Cluster Head according to the energy of the sensor node

  • Kim, Yong Min;LEE, WooSuk;Kwon, Oh Seok;Jung, Kyedong;Lee, Jong-Yong
    • International Journal of Advanced Culture Technology
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    • v.4 no.2
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    • pp.19-26
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    • 2016
  • The most important factor in the wireless sensor network is the use of effective energy and increase in lifetime of the individual nodes in order to operate the wireless network more efficiently. For this purpose, various routing protocols have been developed. The LEACH such a protocol, well known among typical cluster routing protocols. However, when a cluster head is selected, the energy consumption may not be equal because it does not take into account the energy of the nodes. In this paper, we seek to improve the cluster head selection method according to residual energy of each sensor node. This method then adaptively applies the LEACH algorithm and the cluster head section algorithm with consideration of node energy in accordance with the energy of the whole sensor field. Through the simulation, it was found that this proposed algorithm was effective.

Shoot Proliferation of Populus euramericana(Populus deltoides X P. nigra) through in vitro Tissue Culture

  • Kang, Ho-Duck;Moon, Heung-Kyu
    • Plant Resources
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    • v.4 no.3
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    • pp.111-120
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    • 2001
  • The efficiency of in vitro regeneration of four clones of Populus euramericana, Canada blanc, Eugenii, I-45/51, and Wisconsin #5, was examined. Cytokinins and the combinations with auxins affected the rate of regeneration from the explants of root segments, stem internodes, and leaf discs. Overall, BA and the combination with auxins were effective in root segments and leaf discs of the Canada blanc clone, whereas zeatin and the combination with auxins were important in stem internodes of the Wisconsin #5 clone. The highest number of shoots averaging 17.6 $\pm$ 0.47 from root segments in the Canada blanc clone,18.2 $\pm$ 3.0 from stem internodes in the Wisconsin #5 clone, and 17.8 $\pm$ 1.92 from leaf discs in the Canada blanc clone were obtained with 2.0 mg/1 BA, 2.0 mg/l zeatin combined with 0.2 mg/l IAA, and 0.5 mg/l BA combined with 0.05 mg/l 2,4-D, respectively. In particular, the addition of 2,4-D into cytokinin medium promoted shoot proliferation.

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Effect of Light/dark Cycles on Wastewater Treatments by Microalgae

  • Lee, Kwangyong;Lee, Choul-Gyun
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.6 no.3
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    • pp.194-199
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    • 2001
  • Chlorella kessleri cultivated in artificial wastewater using diurnal illumination of 12h light/12h dark (L/D) cycles. The inoculum density was 10(sup)5 cells/mL and the irradiance in light cycle was 45$\mu$mol㎡s(sup)-1 at the culture surface. As a control culture, another set of flasks was cultivated under continuous illumination. Regardless of the illumination scheme, the total organic carbon (TOC) and chemical oxygen demand (COD) was reduced below 20% of the initial concentration within a day. However, cell concentration under the L/D lighting scheme was lower tan that under the continuous illuminating scheme. Thus the specific removal rate of organic carbon under L/D cycles was higher than that under continuous illumination. This result suggested that C. kessleri grew chemoorganotrophically in the dark periods. After 3 days, nitrate was reduced to 136.5 and 154.1mg NO$_3$-N/L from 168.1mg NO$_3$-N/L under continuous illumination and under diurnal cycles, respectively. These results indicate nitrate removal efficiency under continuous light was better than that under diurnal cycles. High-density algal cultures using optimized photobioreactors with diurnal cycles will save energy and improve organic carbon sources removal.

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미세조류의 Methane 발효특성

  • 강창민;최명락
    • Microbiology and Biotechnology Letters
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    • v.24 no.5
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    • pp.597-603
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    • 1996
  • This study was carried out to examine degradation characteristics of microalgae Chlorella vulgaris in methane fermentation. We measured COD and VS reduction, gas and methane productivity, VFA (volatile fatty acid), respectively. Then we calculated material balance and hydrolysis rates in soluble and solid material. The substrate concentration was controlled from 14 gCOD$_{cr}$/l to 64 gCOD$_{cr}$/l in batch cultures, and HRT (hydraulic retention time) controlled from 2 days to 30 days in continuous experi- ments. The results were as follows. In batch culture, accumulated gas productivity increased with the increase of the substrate concentration. The SS and VSS was removed all about 30% increase of substrate concentration and the most of the degradable material removed during the first 10 days. The curve of gas and methane production rate straightly increased until substrate concentration is 26 gCOD$_{cr}$/l. In continuous culture experiments, the removal rates at HRT 10days were 20% for total COD and TOC, respectively. At longer HRT, there was no increase in the removal efficiency. At HRT 15 days, the removal rates were 30% for SS and VSS, respectively. Soluble organic materials were rapidly degraded, and so there was no accumulated. Soluble COD concentration was not increase regardless of HRT-increasing. That meaned the hydrolysis was one of the rate-limiting stage of methane fermentation. The first-order rate constants of hydrolysis were 0.23-0.28 day$^{-1}$ for VSS, and 0.07-0.08 day$^{-1}$ for COD.

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