• Title/Summary/Keyword: selection tube

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Investigation on the Selection of Capillary Tube for the Alternative Refrigerant R-407C

  • Kim, Chang-Nyeun;Park, Young-Moo
    • International Journal of Air-Conditioning and Refrigeration
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    • v.8 no.1
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    • pp.40-49
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    • 2000
  • The capillary tube performance for R-407C is experimentally investigated. The experimental setup is a real vapor-compression refrigerating system. Mass flow rate is measured for various diameter and length while inlet pressure and degree of subcooling are changed. These data are compared with the results of a numerical model. The mass flow rate of the numerical model is about 14% less than the measured mass flow rate. It is found that mass flow rate and length for R-407C are less than those for R-22 under the same condition. Based on this experimental study and the numerical model, a set of design charts for capillary tube of R-407C is proposed.

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The Trial Manufacturing of Inner Bulb of 200W High Pressure Mercurry Lamps (고압수은램프발광관의 시작연구)

  • Chol Kon Chee
    • 전기의세계
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    • v.19 no.2
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    • pp.18-20
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    • 1970
  • Research on the domestic production of arc tube of high pressure mercury lamp. This research is to solve the problem on the domestic manufacturing method for the arc tube of high pressure mercury lamp. (200W). The trial product is favorably compared with its foreign equivalents in its performances and quality. An advancement in manufacturing technology and the strict selection of raw materials will assure its domestification.

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Improvement of Plants by Biotechnology (세포공학을 이용한 식물개량)

  • 윤의수
    • Korean Journal of Plant Resources
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    • v.3 no.1
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    • pp.1-30
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    • 1990
  • The traditional plant imprownent methods consisted of pure line selection, cross breeding, heterosis breeding, polyploid breeding, mutati-onbreeding, ect.Biotechmoiogy is divided into gene spliclng , monocle-nal antibodies , protein engineering , agricultural research, and microbiological engineering. Of these , high plants deal with agricultural research, and the importent part of which is tissue culture and celLculture , Tissue .culture and cell culture are again divided into embryoculture, test tube fertilization, anther and pollen culture, somatichybridization , transformation, recombination, recombinant DNA moleculehybrid plasmid, ect For these haploid production, protoplast culture,protoplast fusion, selection and propagation, ect. , the technical sett-lement is needed.

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Numerical Analysis on Changes in Flowrate of Draft Water and Power by Changing Design Parameters of a Long-Distance Water Circulation (저층수 흡입식 광역 순환장치의 설계변수에 따른 배출량 및 소비동력 변화 특성에 대한 수치 해석 연구)

  • Song, Dong-Keun;Hong, Won-Seok;Kim, Young-Cheol;Park, Myong-Ha
    • The KSFM Journal of Fluid Machinery
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    • v.13 no.1
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    • pp.23-28
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    • 2010
  • A draft tube which has impeller to elevate bottom water and spread it over surface of lake water, induces convective circulation of lake water, a Long-Distance Circulation (LDC). Circulation of lake water make stratified water mixed and enhance DO (Dissolved Oxygen) of bottom water. Circulation rate of water is determined by draft rate of the tube, which is dependent on design parameters of the draft tube system, i. e. dimension of impeller and diffuser, inclined angle of impeller, impeller shape, and rotational speed. In this study, change in draft rate and power consumption of circulation equipment was investigated numerically with changing impeller dimension, angle and rotational speed. It was found that flowrate of draft water was increased as the dimensions of draft tube and impeller, and rotational speed and inclined angle of impeller increased. The power consumption was also elevated with increasing parameter values, and final selection of parameter values was made to satisfy target flowrates and power consumption.

Development of Nursing Practice Guidelines on Enteral Tube Feeding using the Guideline Adaptation Process (간호분야 실무지침의 수용개작 방법론에 따른 경장영양 실무지침의 개발)

  • Cho, Yong Ae;Eun, Young;Gu, Mee Ock;Cho, Myung Sook;Park, Myung Wha;Kim, Kyung Sook;Kim, Jeong Yeun
    • Journal of Korean Clinical Nursing Research
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    • v.20 no.2
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    • pp.147-161
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    • 2014
  • Purpose: This study was aimed to modify and adapt the previously developed, high-quality enteral tube feeding guidelines for the usage in clinical settings in Korea. Methods: Guideline adaptation process was undertaken according to the guideline adaptation manual version 2.0 developed by NECA (Kim, et al., 2011) and the standardized methodology for nursing practice guideline adaptation (Gu, et al. 2012). Results: The modified and adapted enteral tube feeding guidelines were consisted of 11 domains and 95 recommendations. The domains and numbers of recommendations in each domain were: 4 on general issues, 2 on enteral nutrition indication and discontinue, 6 on enteral nutrition device selection, 12 on enteral tube feeding device insertions, 3 on enteral nutrition formular and choices, 16 on enteral tube feeding start and progress, 20 on enteral tube feeding maintenance and management, 15 on monitoring enteral tube feeding administration, 10 on prevention of error, 5 on medication administration, and 2 on documentation and report. There were 16.1% of the recommendations marked as A grade, 17.8% of B grade, and 66.1% of C grade. Conclusion: The adapted enteral tube feeding nursing practice guideline is to be added to the evidence-based practice guidelines for fundamentals of nursing practice. The guideline is hoped to be disseminated to nurses nationwide in order to improve the efficiency of enteral tube feeding practice.

Optimal Design of Compact Heat Exchanger (Louver Fin-tube Heat Exchanger for High Heat Transfer and Low Pressure Drop)

  • Kang, Hie-Chan
    • Journal of Advanced Marine Engineering and Technology
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    • v.35 no.7
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    • pp.891-898
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    • 2011
  • The present work was conducted to get the best geometric information for the optimum design of the complex heat exchanger. The objective function for optimal design was expressed as a combination of pressure drop and heat transfer rate. The geometric parameters for the variables of louver pitch and height, tube width, etc., were limited to ranges set by manufacturing conditions. The optimum geometric parameters were calculated by using empirical correlations and theory. The sensitivity of the parameters and optimum values are shown and discussed. The weighting factor in the objective function is important in the selection of the louver fin-tube heat exchanger.

Anesthetic management of a patient with chromosome 6p duplication: a case report

  • Morinaga, Saori;Tsukamoto, Masanori;Yokoyama, Takeshi
    • Journal of Dental Anesthesia and Pain Medicine
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    • v.17 no.2
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    • pp.139-141
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    • 2017
  • Chromosome 6p duplication is very rare and clinically characterized by short stature, mental retardation, and congenital heart diseases. Patients with mental retardation may present with poor oral health conditions. Dental treatment may need to be performed under general anesthesia in such patients. Our case report deals with induction of general anesthesia to a patient with chromosome 6p duplication, for dental treatment. The selection of a nasotracheal tube of an appropriate size, because of the patient's short stature, was especially important for airway management. In the present case, the patient with chromosome 6p duplication was intubated with a nasotracheal tube, which was not age-matched but adapted to the height and physique of the patient.

Tracheoesophageal Fistula Associated with Endotracheal Intubation (기관삽관과 관련된 경부 기관의 기관식도루)

  • Hah, J. Hun
    • Korean Journal of Bronchoesophagology
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    • v.18 no.2
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    • pp.41-44
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    • 2012
  • Acquired tracheoesophageal fistula (TEF) can occur rarely from various causes. Recently, cuff-related tracheal injury after endotracheal intubation with the orotracheal tube and tracheostomy cannula is the most common etiology of nonmalignant TEF. Since cuff-related TEF is usually preventable with proper selection of the cuffed tube and close monitoring of cuff pressure. Although most patients present increased secretions, recurrent pneumonia, or coughing after swallowing, a high index of suspicion is required in patients at risk for developing a TEF. Surgical correction for the defectis required. In most cases, primary closure of the esophageal defect and tracheal resection and end-to-end anastomosis give the best results.

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A Study of Effects of Wang's Tube in Semen Preparation (정자 준비에서의 Wang's Tube 효과에 관한 연구)

  • Kim, Young-Tae;Kim, Yong-Ook;Kim, Hae-Jung;Kim, Sun-Haeng;Rha, Joong-Yol;Ku, Pyong-Sahm
    • Clinical and Experimental Reproductive Medicine
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    • v.18 no.1
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    • pp.95-99
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    • 1991
  • Swim-up and Wang's tube system are known methods of motile sperm selection and aerobic bacterial removal from the raw semen. This study was designed to evaluate the recovery rate of motile sperm, % normal morphology of sperm, the efficiency of bacterial removal after sperm preparation by the above two methods. The results were as follows. 1. There was more significant increase of sperm concentration in preparation by swim-up than Wang's tube (p<0.05). The concentration of sperm by swim up was changed from $82.5{\times}10^6/ml$ to $6836{\times}10^6/ml$, and Wang's tube was changed from $82.5{\times}10^6/ml$ to $36.0{\times}10^6/ml$. 2. There was significant increase in sperm motility after preparation by two methods in comparison with initial sperm motility (p<0.05), but no statistical difference between two methods was noted. The % motility of sperm by swim-up was increased from 66.1% to 95.7% and Wang's tube from 66.1% to 98.1%. 3. There was significant increase of % normal morphology of sperm in the samples prepared by two methods (p<0.05), from 49.2% to 85.3% in swim-up and from 49.2% to 92.1% in Wang's tube, but there was no statistical significance between them. 4. There was no bacterial growth in aerobic culture after preparation by two methods.

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Selection of Capillary Tubes for HCFC-22 Alternative Fluids (HCFC-22 대체냉매의 모세관 선정)

  • Jung, D.S.;Kim, C.B.
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.7 no.3
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    • pp.435-449
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    • 1995
  • In this paper, pressure drop through a capillary tube is modeled to determine the length of a capillary tube for a given set of conditions. HCFC-22 and its alternatives, HFC-134a, R407B, and R410A are used as working fluids. The conditions on which the model is tested are as follows : condensing temperature; 40.0, 45.0, 50.0, $55.0^{\circ}C$, degree of subcooling;0.0, 2.5, $5.0^{\circ}C$, capillary tube exit condition;choked flow, capillary tube diameter;1.2~2.4mm, mass flow rate;5.0~50.0g/sec. The results justify the use of Stoecker's model which yields the results very close to the values in ASHRAE handbook. While McAdams' method yields much better results than Duckler's in calculating the viscosity of the fluid in 2-phase, the friction factor suggested by Stoecker seems to be the best for capillary tubes of large diameter used in residential air conditioners. For each refrigerant, 372 data with various variables are calculated by the model. The results show that capillary tube length varies very uniformly with changes in condensing temperature and degree of subcooling. Based on this fact, regression analysis is performed to determine the dependence of mass flow rate on the length and diameter of a capillary tube, condensing temperature, and degree of subcooling. Thus determined correlation yields a mean deviation of 2.36% for 1,488 data, showing an excellent agreement.

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