• Journal of Microbiology and Biotechnology
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• 제3권4호
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• pp.292-297
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• 1993

Aspergillus niger No. PFST-38 was grown on complex media in 30L agitated fermentors at various aeration rates and stirrer speeds. We could correlate the mixing time as a function of the Reynolds number and the apparent viscosity, as follows. ${\theta}_M=2.95\;\NRe^{-0.52},\;{\theta}_M=1.88\;{\eta_a}^{0.57}$ Also, the effects of the apparent viscosity (${\theta}_a$), the impeller rotational speed (N), the air flow rate ($V_s$), and the mixing time (${\theta}_M$) on the oxygen transfer coefficient, $K_L a$ were determined experimentally, and equated as follows. $K_La=12.04N^{0.88}Vs^{0.71}{n_a}^{-0.83},\;K_La=30.2N^{0.88}Vs^{0.71}{\theta_M}^{-1.45}$ $K_La$ increased as the agitation speed and the air flow rate increased. The rate of $K_La$ increase was dependent more on the rotational speed of impeller than on the air flow rate. The glucoamylase production increased with the increase of the agitation speed upto at 500 rpm and increased with the increase of air flow rate upto at 1.0 vvm. The values calculated from the above equation confirmed that the experimental maximum production of glucoamylase was achieved when the $K_La$ and the apparent viscosity of the broth were $260\;hr^{-1}$ and 1800 cps, respectively.

• Restorative Dentistry and Endodontics
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• 제39권2호
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• pp.104-108
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• 2014

Objectives: To evaluate the effect of passive ultrasonic agitation on the cleaning capacity of a hybrid instrumentation technique. Materials and Methods: Twenty mandibular incisors with mesiodistal-flattened root shape had their crowns sectioned at 1 mm from the cementoenamel junction. Instrumentation was initiated by catheterization with K-type files (Denstply Maillefer) #10, #15, and #20 at 3 mm from the working length. Cervical preparation was performed with Largo bur #1 (Dentsply Maillefer) followed by apical instrumentation with K-type files #15, #20 and #25, and finishing with ProTaper F2 file (Denstply Maillefer). All files were used up to the working length under irrigation with 1 mL of 2.5% sodium hypochlorite (Biodyn$\hat{a}$mica) at each instrument change. At the end of instrumentation, the roots were randomly separated into 2 groups (n = 10). All specimens received final irrigation with 1 mL of 2.5% sodium hypochlorite. The solution remained in the root canals in Group 1 for one minute; and ultrasonic agitation was performed in Group 2 for one minute using a straight tip inserted at 1 mm from working length. The specimens were processed histologically and the sections were analyzed under optic microscope (x64) to quantify debris present in the root canal. Results: The samples submitted to ultrasonic agitation (Group 2) presented significant decrease in the amount of debris in comparison with those of Group 1 (p < 0.05). Conclusions: The hybrid instrumentation technique associated with passive ultrasonic agitation promoted greater debris removal in the apical third of the root canals.

• 한국항공우주학회지
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• 제34권3호
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• pp.51-59
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• 2006

교반기 내에서의 교반속도 변화에 따라 제조된 자가치료용 마이크로캡슐의 물리적 특성을 입도분석기와 광학현미경을 통해 실험적으로 관찰하였다. 또한 자가치료용 마이크로캡슐의 제조공정을 이해하기 위해 3차원 수치해석의 수행을 통해 교반기 내에서의 유동 특성을 조사하였다. 연구결과에 따르면, 교반기 내에서의 교반속도는 마이크로캡슐의 크기를 결정하는 주요 인자임을 확인하였다. 액체가 혼합된 교반기 내에서는 회전하는 임펠러에 의해 제트와 끝단 와류 성분이 발생하였으며 임펠러의 블레이드 주위에 형성되는 와도는 교반속도가 높아질 때 증가함을 알 수 있었다. 또한 자가치료용 마이크로캡슐의 크기는 끝단 와류와 같은 작은 크기의 혼합 패턴 유동에 큰 영향을 받았다.

• 대한간호학회지
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• 제54권1호
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• pp.32-43
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• 2024

Purpose: This study aimed to determine the impact of an intervention using voice recording of family members on pain, anxiety, and agitation in patients undergoing weaning from mechanical ventilation. Methods: A randomized control pre-post experimental design was implemented to 53 participants, with 27 and 26 participants in the experimental and control groups, respectively. A 70-second voice recording of a family member, repeated three times at 10-minute intervals was used as an intervention for the experimental group. Meanwhile, participants in the control group used headset for 30 minutes. Structured instruments were utilized to measure pain, anxiety, agitation, and the weaning process. Wilcoxon Signed Ranks test and the Mann-Whitney U test, or χ² test, were used for data analysis. Results: The experimental group exhibited significant decrease in pain (Z = - 3.53, p < .001), anxiety (t = 5.45, p < .001), and agitation (Z = - 2.99, p = .003) scores compared with those of the control group. However, there was no significant difference between groups in the weaning process' simplification (χ² = 0.63, p = .727). Conclusion: Intervention using family members' voice recording effectively reduces pain, anxiety, and agitation in patients undergoing weaning from mechanical ventilation. This can be actively utilized to provide a more comfortable process for patients.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2001년도 추계학술발표대회
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• pp.382-385
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• 2001

The effect of agitation speed on the production of mycelial growth and exo-biopolymer in bioreaetor culture was investigated. The maximum production of mycelia and exo-biopolymer was obtained at 350 rpm, where the maximum concentrations of mycelial growth and exo-biopolymer were 62 g/L and 23 g/L, respectively. The effect of agitation speed on the hyphal length and the number of tips was examined. The hyphal length and the number of tips of Cordyceps sinensis 16 in bioreaetor culture at 350 rpm were increased up to 660 ${\mu}m$ and 14/ml, respectively.

• Journal of Mechanical Science and Technology
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• 제19권3호
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• pp.860-869
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• 2005

Local pool boiling on the outside and inside surfaces of a 51 mm diameter tube in horizontal direction has been studied experimentally in saturated water at atmospheric pressure. Much variation in local heat transfer coefficients was observed along the tube periphery. On the outside surface the maximum and the minimum are observed at ${\theta}=45^{\circ}$ and $180^{\circ}$, respectively. However, on the inside surface only the minimum was observed at ${\theta}=0^{\circ}$. Major mechanisms on the outside surface are liquid agitation and bubble coalescence while those on the inside surface are micro layer evaporation and liquid agitation. As the heat flux increases liquid agitation gets effective both on outside and inside surfaces. The local coefficients measured at ${\theta}=90^{\circ}$ can be recommended as the representative values of both outside and inside surfaces.

• 한국산업융합학회 논문집
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• 제14권2호
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• pp.73-78
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• 2011

Power consumption for wire gauge impeller in cylindrical agitated vessel was measured over a wide range of Reynolds number from laminar to turbulent flow regions. The power correlation were obtained agitation power input of WM4 at gassing condition in turbulent region, at gassing condition in transient region and at gassing condition in laminar region. Also the compared with effect of impeller diameter and blade width on agitation power input at gassing condition in turbulent region, at gassing condition in transient region and at gassing condition in laminar region.

• Corrosion Science and Technology
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• 제2권4호
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• pp.197-201
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• 2003

In this study, Ni-P layers were electroplated on the surface of stainless steel in order to investigate the effects of an additive and agitation on their mechanical properties and microstructure. The concentration of the additive in the plating solution increased, the pores formed in the layer decreased, while the residual stress developed in the layers during electroplating increased. Agitation of the solution during electroplating was observed to force to increase local pores in the layer, which lowers its tensile properties. Grain growth was suppressed due to very fine $Ni_3P$ precipitates formed at its grain boundaries during heat treatment at $343^{\circ}C$ for 1 hr in air.

• Journal of Korean Neurosurgical Society
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• 제43권5호
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• pp.242-245
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• 2008

A 64-year-old man with TBI was admitted to our institute. In following days, he showed unusual behavior of agitation, restlessness, emotional instability and inattention. Post-traumatic delirium was tentatively diagnosed, and donepezil was given for his cognitive dysfunction. Although there was partial relief of agitation, he sustained back pain despite medication. Lumbar magnetic resonance image revealed SDH along the whole lumbar spine, and surgical drainage was followed. Postoperatively, his agitation disappeared and further medication was discontinued. We report a unique case of post-traumatic delirium in a patient with concomitant TBI and spinal subdural hemorrhage (SDH) that resolved with operative drainage of spinal hemorrhage.

• 생명과학회지
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• 제6권2호
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• pp.129-134
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• 1996

The development of fish feed is essential to aquaculture. Recently, yeast, dhlorella and plankton have been studied and development as the feed of the fry fishes, But, these biological feeds cause the nutritional unbalance to fry fishes, rotifer or artemia. Therefore, to solve these problems, microcapsules with micron sizes were prepared for enhancing the nutritional values of artemia and rotifer which are used as the feed of fry fishes. Microparticle oil capsules were prepared by the complex coacervation technique. The method to make the optimal size of microcapsule which the artemia and rotifer can be easily taken was wvaluated. The size of oil microcapsule in the range of 5-70$\mu$m was obtained by the agitation conditions during coacervation. Capsule size and size distribution were dependent on the agitation speed and agitation time, respectively.