• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1976.10a
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• pp.187.3-187
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• 1976

건조 유산균 starter (Lyophillized lactic sarter) 제조 과정 중 동결건조에 의한 viability의 저하를 방지하는 방법의 하나로서 유산균을 농축 (concentrate) 시켰다. 유산균을 농축시키기에 앞서 cell의 농도를 높여줄 필요가 있었으므로 Cell의 증식에 영향을 미치는 요인으로 agitation 및 aeration을 채택하여 그것이 cell의 증식 및 lactic acid producing ability에 미치는 영향을 조사한 결과 다음과 같은 사실을 알 수 있었다.(중략)

• Proceedings of the Korea Concrete Institute Conference
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• 1998.04a
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• pp.29-32
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• 1998

In this paper, the properties of the agitation noise of agitator truck when flowing concrete practice is applied in construction field of our country are investigated. According to the experimental results, the solution on the noise during the agitation in flowing concrete should be considered in order to apply flowing concrete into construction field without the problems such as a civil appeal.

• Applied Chemistry for Engineering
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• v.2 no.3
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• pp.209-215
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• 1991

The effect of agitation on the dispersion of organic phase was investigated in an immiscible liquid system (n-hexane/40 wt % p-TSA aqueous solution). Four different types of six-bladed turbine impellers were used : a flat blade type and three screen blade types. The experimental results showed that the extent of dispersion of organic phase at the same agitation speed was decreased in the order of flat blade, 60 mesh, 40 mesh, and 20 mesh screen blades. Otherwise, it was increased with increasing the concentration of TBA as a surfactant agent and with decreasing volume fraction of organic phase. Also, the minimum agitation speed for a complete dispersion was increased in the order of flat blade, 60 mesh, 40 mesh, and 20 mesh screen blades. However, the minimum power consumption did not vary significantly. In this condition, the relationship between Power number and Reynolds number was expressed as $N_p=a\;N_{Re}{^b}$, where the values of constant a and constant b were ranged 2200~4100 and -0.69~-0.63 respectively.

• Economic and Environmental Geology
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• v.34 no.4
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• pp.417-422
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• 2001

Sutfactants may be used in remediation of subsoil and aquifer contaminated with hydrophobic compounds. The objectives of this study were to select potentially suitable sUlfactants that solubilize toluene present as a contaminant and to determine the effectiveness of toluene removal from Ottawa sand by the selected surfactants. Material used as the model soil was Ottawa sand and the organic used as model contaminant was toluene. Used experimental methods were separatory funnel experiment and shaker table agitation/centrifugation experiments. Based on the experimental results, the following conclusions were drawn; t) In the surfactant selection, six different surfactants were chosen based on surfactant types, toxicity, and water solubility. These six were focused into two on the basis of HLB and surface tension study, separatory funnel experiment, shaker table and centrifugation experiments. The two most suitable surfactants were Sandopan JA36 (an anionic surfactant), and Pluronic L44 (a non-ionic surfactant). 2) In the shaker table agitation and centrifugation experiments, the highest recovery of the toluene was 96% which was obtained with one surfactant wash plus two water rinses using an anionic surfactant (Sandopan JA36).

• Korean Journal of Environmental Agriculture
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• v.17 no.4
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• pp.301-305
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• 1998

This study was conducted to evaluate the liquid composting efficiency using pig manure in different condition such as simple storage type reactor, continuous aeration reactor, anaerobic reactor and anaerobic agitation reactor. Continuous aeration reactor was the most efficiency method to BOD and malodors removal than other methods. While nitrogen loss in continuous aeration reactor was 47% of initial concentration, which was the higher amount than any other digestion methods. The digestion efficiency between anaerobic reactor and anaerobic agitation reactor were similar, but E. coli and malodor removal efficiency were a little higher in the anaerobic agitation reactor. Simple storage type reactor which was conventional digestion method in rural area gave lower efficiency than aerobic and anaerobic digestion methods in view of BOD, E. coli and malodor removal. The liquid composting efficiency which were evaluated by various indicators like pH, BOD, E, coli, malodor and nitrogen loss was high in the order of anaerobic agitation reactor>continuous aeration reactor>anaerobic reactor>simple storage type reactor.

• Journal of the Korea Organic Resources Recycling Association
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• v.9 no.4
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• pp.99-104
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• 2001

The influence of agitation speed on the yeast growth was investigated in the production of probiotic feed from pulverized liquified food wastes by aerobic fermentation. A yeast Kluyvermyces marxianus was selected through a preliminary screening. The yeast was cultured by 2liter jar fermenter. in 10% solid(w/v) substrate of liquified food waste at $35^{\circ}C$ with each different agitation speed of 500, 900 and 1200 rpm. For the acceleration of enzyme excretion mixed culture with Aspergillus oryzae was also attempted and the results were compared to those of single culture. As results the viable cell number was increased by increasing agitation speed. But it showed highest value in 900rpm and then decreased in 1200rpm. The mixed culture increased amylase activity and growth rate, but did not seem to enhance the highest viable cell count in the final fermentation stage.

• Journal of Korean Academy of Nursing
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• v.47 no.1
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• pp.98-109
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• 2017

Purpose: This aim of this phenomenological study was to describe and understand the experience of spiritual conflict in hospice nurses by identifying the meanings and structures of the experience. Methods: Participants were 12 nurses working for one year or more at hospice units of general hospitals in a metropolitan city and experiencing of spiritual conflict as hospice nurses. Over six months data were collected using individual in-depth interviews and analyzed with the method suggested by Colaizzi. Results: The experience of spiritual conflict in participants was organized into three categories, six theme-clusters, and 13 themes. The participants felt existential anxiety on death and a fear of death which is out of human control and skepticism for real facts of human beings facing death. They also experienced agitation of fundamental beliefs about life with agitation of the philosophy of life guiding themselves and mental distress due to fundamental questions that are difficult to answer. Also they had distress about poor spiritual care with guilty feelings from neglecting patients' spiritual needs and difficulties in spiritual care due to lack of practical competencies. Conclusion: Findings indicate the experience of spiritual conflict in hospice nurses is mainly associated with frequent experience of death in hospice patients. The experience of spiritual conflict consisted of existential anxiety, agitation of fundamental beliefs and distress over poor spiritual care. So, programs to help relieve anxiety, agitation and distress are necessary to prevent spiritual conflict and then spiritual burnout in hospice nurses.

• Biotechnology and Bioprocess Engineering:BBE
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• v.9 no.3
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• pp.184-190
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• 2004

The influences of impeller types on morphology and protein expression were investigated in a submerged culture of Aspergillus oryzae. The impeller types strongly affected mycelial morphology and protein production in batch and fed-batch fermentations. Cells that were cultured by propeller agitation grew in the form of a pellet, whereas cells that were cultured by turbine agitation grew in a freely dispersed-hyphal manner and in a clumped form. Pellet-grown cells showed high levels of protein production for both the intracellularly heterologous protein (${\beta}$-glucuronidase) and the extracellularly homologous protein (${\alpha}$-amylase). The feeding mode of the carbon source also influenced the morphological distribution and protein expression in fed-batch fermentation of A. oryzae. Pulsed-feeding mainly showed high protein expression and homogeneous distribution of pellet whereas continuous feeding resulted in less protein expression and heterogeneous distribution with pellet and dispersed-hyphae. The pellet growth with propeller agitation paralleling with the pulsed-feeding of carbon source showed a high level of protein production in the submerged fed-batch fermentation of recombinant A. oryzae.

• Korean Journal of Soil Science and Fertilizer
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• v.50 no.5
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• pp.325-335
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• 2017

This study was carried out for 30 days in aeration type and agitation type reactor to characterize organic matter decomposition and ammonia volatilization during the liquid composting of pig slurry, and organic matter and nitrogen removal rate through mass balance analysis was analyzed. In the aeration type reactor, the pH increased from 7.0 to 9.13, and TS 34.5%, VS 33.4%, $BOD_5$ 71.2%, $COD_{Cr}$ 62.3% and TOC 83.2% were removed. In addition, 44.6% of TN and 65.0% of ${NH_4}^+-N$ were removed. In the agitation type reactor, the pH increased from 7.0 to 8.10, and the removal rates of TS 0.9%, VS 0.5%, $COD_{Cr}$ 27.5%, $BOD_5$ 28.9% and TOC 41.3% were obtained. And TN and ${NH_4}^+-N$ showed removal rate of 25.3% and 29.2%, respectively. The first order kinetics constant related to $BOD_5$ degradation was $-0.039day^{-1}$ for aerobic liquid composting and $-0.013day^{-1}$ for agitated reactor. Nitrogen loss in aerobic liquid composting was about 2.3 times higher than that of agitated reactor, whereas FAN/TAN in aerobic liquid composting was about 7.9 times higher than that of agitation type reactor. Therefore, despite the low FAN/TAN in the agitation type reactor, the nitrogen loss rate was relatively high.

• Journal of the Korean Society of Industry Convergence
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• v.23 no.4_2
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• pp.617-626
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• 2020

The drilling mud is essentially used in oil and gas development. There are several roles of using the drilling mud, such as cleaning the bottomhole, cooling and lubricating the drill bit and string, transporting the cuttings to the surface, keeping and adjusting the wellbore pressure, and preventing the collapse of the wellbore. The fragments from rocks and micro-sized bubbles generated by the high pressure are mixed in the drilling mud. The systems to separate those mixtures and to keep the uniformly maintained quality of drilling mud are required. In this study, the simulation is conducted to verify the performance of the mud tank's agitation capacity. The primary role of the mud tank is the mixing of mud at the surface with controlling the mud condition. The container type is chosen as a mud tank pursuing efficient transport and better management of equipment. The single- and two-phase simulations about the agitation in the mud tank are performed to analyze and identify the inner flow behavior. The convergence of results is obtained for the vertical- and axis-direction velocity vector fields based on the grid-dependency tests. The mixing time analysis depending on the multiphase flow conditions indicates that the utilization of a two-stepped impeller with a smaller size provides less time for mixing. This study's results are expected to be utilized as the preliminary data to develop the mixing and integrating equipment of the onshore drilling mud system.