• Journal of Chest Surgery
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• 제47권3호
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• pp.220-224
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• 2014

Background: For the surgical management of anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA), there have been various techniques that reduce the tension and kinking of the coronary artery during reimplantation to the aorta. The aim of this study is to describe the results of our modified technique of coronary reimplantation for the treatment of ALCAPA. Methods: Between October 2003 and February 2011, seven patients underwent coronary reimplantation with the modified technique (tubing formation with the sinus wall of the pulmonary artery and trapdoor formation at the site of implantation in the aorta). The median follow-up duration was 52 months (range, 4 to 72 months). Clinical outcomes and serial echocardiographic data were reviewed. Results: There was no mortality. One patient had a small amount of cerebral hemorrhage postoperatively and improved without any sequelae. Another patient had left diaphragm palsy and underwent diaphragm plication. Follow-up echocardiogram showed that all patients had normal ventricular function without chamber enlargement. Conclusion: Our modified technique (tubing formation with the sinus wall of the pulmonary artery and trapdoor formation at the site of implantation in the aorta) demonstrated successful clinical outcomes. We conclude that this surgical technique can be a potential alternative for the treatment of ALCAPA.

• Nuclear Engineering and Technology
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• 제55권1호
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• pp.109-118
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• 2023

In this paper, the evaluation method of fluidelastic instability (FEI) of newly designed steam generator tubing in pressurized water reactor (PWR) nuclear power plants is discussed. To obtain the parameters for prediction of the critical velocity of FEI for steam generator tubes, experimental research is carried out, and the design parameters are determined. Using CFD numerical simulation, the tube array scale of the model experiment is determined, and the experimental device is designed. In this paper, 7 groups of experiments with void fractions of 0% (water), 10%, 20%, 50%, 75%, 85% and 95% were carried out. The critical damping ration, fundamental frequency and critical velocity of FEI of tubes in flowing water were measured. Through calculation, the total mass and instability constant of the immersed tube are obtained. The critical damping ration measured in the experiment mainly included two-phase damping and viscous damping, which changed with the change in void fraction from 1.56% to 4.34%. This value can be used in the steam generator design described in this paper and is conservative. By introducing the multiplier of frequency and square root of total mass per unit length, it is found that the difference between the experimental results and the calculated results is less than 1%, which proves the rationality and feasibility of the calculation method of frequency and total mass per unit length in engineering design. Through calculation, the instability constant is greater than 4 when the void fraction is less than 75%, less than 4 when the void fraction exceeds 75% and only 3.04 when the void fraction is 95%.

• 핵의학기술
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• 제14권1호
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• pp.8-12
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• 2010

$^{18}F$-FDG 자동합성장치에서 합성 후 자동분배장치까지는 자동모드로 delivery를 하게 되는데, delivery 후 자동분배장치에 있는 dose calibrator가 표시한 방사능으로 계산하여 수율이 계산되어진다. 그러나 자동합성장치와 자동분배장치의 거리가 증가하게 되면 튜빙에 $^{18}F$-FDG 잔류량이 발생하게 되어 $^{18}F$-FDG의 손실이 있다. 본 연구는 $^{18}F$-FDG 잔류량을 최소화하기 위한 방법의 유용성에 관하여 알아보았다. 싸이클로트론에서 생산된 $^{18}F$는 자동합성장치로 이동되고 자동합성장치에서 합성이 이루어지며, 합성 과정의 소요 시간은 25~26분이 소요된다. 그 후 dispenser로 $^{18}F$-FDG를 delivery하고 자동합성장치 자체 rinsing으로 모든 과정이 끝마쳐진다. 자동합성장치와 자동분배장치 사이의 튜빙의 구성은 거리 8 m, 내경 1/16 inch로 되어 있다. 그러나 delivery 후 튜빙 거리 증가에 따라 $^{18}F$-FDG 잔류량이 10-13%가 발생하게 되었다. 따라서 $^{18}F$-FDG 잔류량을 최소화하기 위하여 첫번째는 자동합성장치의 자동모드로 delivery, 두번째로 자동모드 delivery 후 push syringe 이용한 방법, 세번째로 자동모드 delivery후 push syringe와 질소가스를 병행한 방법을 시행하여 delivery 수율의 변화를 비교 분석하였다. 첫번째 방법에서 delivery 시에 QMA 기준으로 42.22%, 두번째 방법에서는 49.15%, 세번째 방법에서는 54.05%의 결과를 얻었다. Delivery 되어진 $^{18}F$-FDG 의 품질관리평가상에서도 정상의 결과를 얻었다. 합성장치와 자동합성장치의 거리는 최대한 단축시켜 튜빙거리로 인한 $^{18}F$-FDG 손실율을 낮추어야 한다. 그러나 시스템구조에 따라 자동합성장치와 자동분배장치의 거리가 증가되는 경우에 push syringe와 범용성 이동가스(질소 가스)를 병행하는 방법이 $^{18}F$-FDG 잔류량을 최소화하는 방법으로 유용하다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회B
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• pp.3187-3190
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• 2007

Elastin-Like polypeptide (ELP) composed of elastin-based repeating units is an artificial biomaterial which is biocompatible and non-immunogenic. ELP shows a characteristic inverse phase transition between hydrophobic and hydrophilic phase by external stimuli such as salt, pH and temperature. In this study, ELP coated PS (polystyrene) beads are packed in tubing and the thermo -responsive flow characteristics of the packed bed are investigated. Preliminary test results show that the control of the fluid flow can be achieved by using the temperature driven phase transition effect of the ELP coated beads in a microchannel.

• Applied Biological Chemistry
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• 제41권8호
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• pp.583-586
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• 1998

Porous ceramic cups are used for monitoring ion concentration in soil solutions in various time course and depth. A soil solution sampler was constructed in laboratory by inserting pliable perfluoroalkoxy(PFA) tubings into porous cup through holes in PVC rod segment which plugged top opening of the porous cup. The system was installed in drip irrigated soil in a vertical position, and nitrogen movement below the drip basin was monitored. To collect soil solution, vacuum in the cup was applied with a hand vacuum pump. The samples obtained were sufficient enough to run quantitative analyses for a number of chemicals. Nitrogen transformation and movement could be well defined, and the system seemed to be relevant to the other soil solution samplers in monitoring chemical movement in soil. Although this system has general deficiencies found in the other samplers using ceramic cup, it could be easily constructed at a low cost. Since the tubing was pliable, the cups could be installed in horizontal position, and this allows installations of the cups at more precise depth increments and also more precise samplings of soil solution at each depth.

• 한국세라믹학회지
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• 제29권12호
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• pp.919-925
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• 1992

Continuous synthesis process for monodispersed zirconia powders with ultrasonic wave mixing was developed. Reactant solutions were flowed through a T-tube with small diameter and then mixed in a microscale with ultrasonification. Reaction and aging were followed during the mixed solution of reactants is in plug flowing through a narrow long teflon tubing. Zr(n-OC4H9)4 in ethanol and H2O in ethanol were used as reactants. From this process monodispersed, spherical, non-agglomerated, singlet hydrated zirconia powders with 0.6 $\mu\textrm{m}$ average size were obtained. Geometrical standard deviation of the particle size distribution was less than 1.2 with ultrasonic mixing, and the geometrical standard deviation was not affected by the flow rate of the reactants.

• KSBB Journal
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• 제15권4호
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• pp.380-387
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• 2000

An extractive fermentation process using pervaporation was studied in a 7 liter fermentor. Pervaporation was performed using a silicone membrane module and a low-acid-producing strain Clostridium acetobutylicu, B18 was used to produce butanol. In batch culture without pervaporation pH 5.5 and initial glucose concentration of 60 g/L resulted in the highest butanol productivity (0.216 g/L$.$h) with butanol yield of 0.261 Butanol flux through the membrane was best at 2.0 L/min-tubing of air flow rate In batch and fed-batch fermentation glucose consumption rate increased by 1.3 times with pervaporation.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 추계학술대회 논문집
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• pp.60-63
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• 2004

An innovative in-core neutron flux mapping system has been developed and applied successfully for service in a commercial pressurized water reactor. With the benefit of double indexing path selector (Dip $s^{ⓡ}$) mechanism, the reliability of the detector drive system has been improved five times higher than that of conventional systems, and the problems caused by the serious friction generated between the detector cable and guide tubing has been solved completely because the Dip $s^{ⓡ}$ architecture allows the detector guide tubings to have larger curvature and shorter length in nature. The simple and fast maintenance is particularly emphasized in the detector drive system to secure minimum radiation exposure to the maintenance personnel by optimizing the number of components and providing easy access to the components. The programmable logic controller based digital controller with Window $s^{ⓡ}$ based operator s console provides fully automated and user friendly operation and maintenance support means.

• Environmental Analysis Health and Toxicology
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• 제16권4호
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• pp.171-179
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• 2001

A new passive sampler was developed, improving SPMD (Semipermeable Membrane Devices) that contained triolein in nonporous, low-density polyethylene layflat tubing. Experiments to measure PAHs concentration were carried out at four sites (Dukpo, Sochi, Sohwonggando, Yeonmok) on the southern coast of Korea that were contaminated by oil spills. Passive samplers were deployed at 4 and 8 week intervals at each site. Results showed that bioconcentration levels of PAHs were increased in proportion to exposure duration from all sample sites and accumulation in the passive sampler was much higher than in biota at the Dukpo site. Results of these tests suggest that new passive sampler is a useful tool for measuring bioconcentration organic compounds in aquatic environments.

• 환경위생공학
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• 제16권3호
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• pp.8-13
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• 2001

This study was carried out effect of red ginseng extract(1.0g/kg) on organotin compounds (10, 20 and 40 mg/kg) which poisons against some organs like thyroid gland, liver, kindey, testis, ovary, serum immuinty and sex hormone activity of rats were examinned by gastric tubing for 3 weeks. The weight of each organ in TBTO treated group were significantly increased other organs which excepted kinedy in males and only liver in females.(p<0.05, p<0.01). In case of Immunity activity of each sex, IgM level was small change comparsion with that of control group in all sex. but IgG level was significantly decreased females rather than males comparsion with that of control group.(p<0.05, p<0.01) In case of sex hormone activity, the testosterone activity of males and the estradiol activity of females were significantly decreased rather than the control group. on the other hand, red singsong treated group was only significantly increased estradiol activity.( p<0.05, p<0.01)