• Title/Summary/Keyword: General bubbles

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Effect of Micro Bubble on Growth of Ginseng in the shaded plastic houses and Possibility of High Quality Ginseng processing (하우스 종묘삼 재배에서 마이크로 버블(Micro bubble) 사용이 생육에 미치는 영향과 고품질 인삼 가공의 가능성)

  • Ahn, C.H.
    • Journal of Practical Agriculture & Fisheries Research
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    • v.19 no.1
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    • pp.109-117
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    • 2017
  • In the production of organic Panax ginseng, the morphological changes were confirmed by providing general water and microbubble water, respectively. Analysis of seedling ginseng treated with general water and bubbles water revealed that many seedlings were formed in the seedling treated with bubble water, and about 15% weight increase occurred in the growing period. The growth rate of stem, leaf, and root was about 15% higher than that of all. Taken together, the growth of seedling cultivation using bubble water was about 15% overall. In order to process ginseng, the dried ginseng was higher in dry weight than the general water seedling seedlings grown in bubble water. This suggests that more processed products will be produced per unit weight at the time of producing the processed products at the farm, which can directly increase the farm income.

Cool-down test of cryogenic cooling system for superconducting fault current limiter

  • Hong, Yong-Ju;In, Sehwan;Yeom, Han-Kil;Kim, Heesun;Kim, Hye-Rim
    • Progress in Superconductivity and Cryogenics
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    • v.17 no.3
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    • pp.57-61
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    • 2015
  • A Superconducting Fault Current Limiter is an electric power device which limits the fault current immediately in a power grid. The SFCL must be cooled to below the critical temperature of high temperature superconductor modules. In general, they are submerged in sub-cooled liquid nitrogen for their stable thermal characteristics. To cool and maintain the target temperature and pressure of the sub-cooled liquid nitrogen, the cryogenic cooling system should be designed well with a cryocooler and coolant circulation devices. The pressure of the cryostat for the SFCL should be pressurized to suppress the generation of nitrogen bubbles in quench mode of the SFCL. In this study, we tested the performance of the cooling system for the prototype 154 kV SFCL, which consist of a Stirling cryocooler, a subcooling cryostat, a pressure builder and a main cryostat for the SFCL module, to verify the design of the cooling system and the electric performance of the SFCL. The normal operation condition of the main cryostat is 71 K and 500 kPa. This paper presents tests results of the overall cooling system.

A Study on Dynamic Strength Analysis of Submarine Considering Underwater Explosion (내충격 성능을 고려한 수중함 동적 강도 설계에 관한 연구)

  • Son, Sung-Wan;Choi, Su-Hyun;Kim, Kuk-Su
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2000.06a
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    • pp.1185-1191
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    • 2000
  • In general, the strength of hull structures can be estimated from stress evaluation considering static and hydro-dynamic load due to sea-wave. However, war ships such as submarine, have frequently experienced the underwater explosion and local structures of ship as well as hull girder can be damaged by the dynamic response excited from underwater non-contact explosion. When explosion happens at underwater, shock wave is radiated In early short time, then gas bubbles are generated, and expansion and contraction are repeated as they float to the surface. The shock wave causes the damage of equipment and its supporting structures, on the other hand, the hull girder strength can be lost by resonance between bubble pulsation and lowest ship natural vibration period. In this paper, the hydro-Impulse force due to bubble was calculated. Based on these results the hull girder strength of submarine was estimated from transient response analysis by using NASTRAN. Also, shock analysis for some equipment supporting structures was carried out by using DDAM. In order to evaluate the strength of these local structures due to shock wave.

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Solid Separation and Flotation Characteristics of Livestock Wastewater Using DAF Process (DAF 공정을 이용한 축산폐수의 고형물 분리와 부상특성)

  • Kang, Byong-Jun;Yoo, Seung-Joon;Lee, Se-il;Kwak, Dong-Heui
    • Journal of Korean Society of Water and Wastewater
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    • v.22 no.3
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    • pp.359-366
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    • 2008
  • The series of experiments under the various conditions were carried out to evaluate the feasibility of dissolved air flotation (DAF) as an alternative of conventional gravity sedimentation (CGS) and to investigate the decrease of the loadings following to biological wastewater treatment processes in livestock wastewater system. On the basis of the experiment result between CGS and DAF processes, for the other water quality criteria as well as suspended solid the removal efficiency of DAF process was about 20~25 % better than CGS process on average. In addition, the particle removal efficiency of DAF process became higher in proportion as the increase of air to solid (A/S) ratio and the general wastewater treatment efficiency of DAF process was enough to meet the requirement of loading decrease to following biological process even at low A/S ratio range. Though DAF process is widely known as an solid separation unit, there was not the notable relationship between particle separation efficiency and several pollutant removal efficiencies like $COD_{Cr}$ and nutrients (T-N, T-P). Assume that the $COD_{Cr}$ was removed as the fraction of particle separation in this experiment, the removal efficiency of T-N and T-P were sensitive to removal efficiency of $COD_{Cr}$, especially.

Effect of Fine Bubble Treatment on the Growth of Two-year-old Ginseng (2년 근 인삼재배 시 파인버블(Fine bubble)처리가 생육에 미치는 영향)

  • Ahn, Chul-Hyun
    • Korean Journal of Plant Resources
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    • v.30 no.5
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    • pp.549-555
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    • 2017
  • The production of ginseng cultivation is decreasing due to shortage of cultivated land and climate change, so additional methods are needed. Therefore, the physiological and morphological characteristics of finebubble were analyzed by applying them to ginseng cultivation which is the representative crop of Korea. The application of fine bubble water to 2 year old ginseng showed that stem length and leaf were increased, and weight increased as main root increased in root. In particular, it is shown that the weight of roots increases with the increase of leaf size. This is because the total chlorophyll content is high and it is judged to be related to the increase of photosynthesis efficiency. When the results of this study were confirmed, it was confirmed that ginseng cultivation using fine bubbles showed no inhibition of growth of ginseng. According to the results of physiological characteristics and subdividing results, It was confirmed that the growth of about 10% to 15% of the growth was increased and that the growth of ginseng was increased by applying the fine bubble when growing ginseng.

IN-LINE NIR SPECTROSCOPY AS A TOOL FOR THE CONTROL OF FERMENTATION PROCESSES IN THE FERMENTED MEATS INDUSTRY

  • Tamburini, Elena;Vaccari, Giuseppe;Tosi, Simona;Trilli, Antonio
    • Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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    • 2001.06a
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    • pp.3104-3104
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    • 2001
  • The research described here was undertaken with the aim of monitoring, optimizing and ultimately controlling the production of heterofermentative microbes used as starters in the salami industry. The use of starter cultures in the fermented meats industry is a well-established technique used to shorten and standardize the ripening process, and to improve and control the organoleptic quality of the final product. Starter cultures are obtained by the submerged cultivation of suitable microorganisms in stirred, and sometimes aerated, fermenters where monitoring of key physiological parameters such as the concentration of biomass, substrates and metabolites suffers from the general lack of real-time measurement techniques applicable to aseptic processes. In this respect, the results of the present work are relevant to all submerged fermentation processes. Previous work on the application of on-line NIR spectroscopy to the lactic acid fermentation (Dosi et al. - Monreal NIR1995) had successfully used a system based on a measuring cell included in a circulation loop external to the fermenter. The fluid handling and sterility problems inherent in an external circulation system prompted us to explore the use of an in-line system where the NIR probe is immersed in the culture and is thus exposed to the hydrodynamic conditions of the stirred and aerated fluid. Aeration was expected to be a potential source of problems in view of the possible interference of air bubbles with the measurement device. The experimental set-up was based on an in-situ sterilizable NIR probe connected to the instrument by means of an optical fiber bundle. Preliminary work was carried out to identify and control potential interferences with the measurement, in particular the varying hydrodynamic conditions prevailing at the probe tip. We were successful in defining the operating conditions of the fermenter and the geometrical parameters of the probe (flow path, positioning, etc.) were the NIR readings were reliable and reproducible. The system thus defined was then used to construct and validate calibration curves for tile concentration of biomass, carbon source and major metabolites of two different microorganisms used as salami starters. Real-time measurement of such parameters coupled with the direct interfacing of the NIR instrument with the PC-based measurement and control system of the fermenter enabled the development of automated strategies for the interactive optimization of the starter production process.

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