• Asian-Australasian Journal of Animal Sciences
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• v.31 no.9
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• pp.1491-1499
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• 2018

Objective: This study was designed to investigate the effects of an Aspergillus sulphureus xylanase expressed in Pichia pastoris on the growth performance, nutrient digestibility and gut microbes in weanling pigs. Methods: A total of 180 weanling pigs (initial body weights were $8.47{\pm}1.40kg$) were assigned randomly to 5 dietary treatments. Each treatment had 6 replicates with 6 pigs per replicate. The experimental diets were wheat based with supplementation of 0, 500, 1,000, 2,000, and 4,000 U xylanase/kg. The experiment lasted 28 days (early phase, d 0 to 14; late phase, d 15 to 28). Results: In the early phase, compared to the control, average daily gain (ADG) was higher for pigs fed diets supplemented with xylanase and there was a quadratic response in ADG (p<0.05). In the entire phase, ADG was higher for the pigs fed 1,000 or 2,000 U/kg xylanase compared to the control (p<0.05). The gain to feed ratio was higher for pigs fed diets supplemented with 1,000 or 2,000 U/kg xylanase compared to the control (p<0.05). Increasing the amount of xylanase improved the apparent total tract digestibility of dry matter, crude protein, neutral detergent fiber, calcium, and phosphorus during both periods (p<0.05). Xylanase supplementation (2,000 U/kg) decreased the proportion of Lachnospiraceae (by 50%) in Firmicutes, but increased Prevotellaceae (by 175%) in Bacteroidetes and almost diminished Enterobacteriaceae (Escherichia-Shigella) in Proteobacteria. Conclusion: Xylanase supplementation increased growth performance and nutrient digestibility up to 2,000 U/kg. Supplementation of xylanase (2,000 U/kg) decreased the richness of gut bacteria but diminished the growth of harmful pathogenic bacteria, such as Escherichia-Shigella, in the colon.

• Clinical and Experimental Reproductive Medicine
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• v.11 no.2
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• pp.5-15
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• 1984

본 연구는 황체기 단축현상(Short luteal phase, SLP) 을 가진 한국여성의 월경주기내 Prolactin 호르몬의 농도변화를 정상월경주기 (Normal luteal phase, NLP)와 비교하고져 하였다. 한편, Circadian rhythm 내 PRL 농도의 변화를 비교하고 임신기간중 PRL의 농도변화를 방사면역측정법(RIA) 으로 조사하였다. SLP여성의 PRL 농도는 후기의 여포성숙기(Late follicular phase) 및 초기황체형성기(Early IuteaI phase) 정상에 비하여 현저히 낮았다. 정상 월경주기에서는 PRL/Progesterone(mU/1/mg/ml)의 비율이 후기 여포성숙기까지 증가한 후 LH Peak day 이후 감소하는데 반하여 SLP여성의 비율은 조기 여포성숙기부터 계속적인 감소현상을 보였다. 또한 취침전 (04:00시) PRL의 농도는 SLP여성에게는 현저히 낮았다. 임신주기중 PRL의 농도는 4개월째 1,077mU/l 에서부터 9개월째 4,462mU/l까지 점진적인 증가를 하였다. 위의 결과로 보아 황체기단축현상은 PRL의 분비이상이 하나의 주요요인이 될 수 있으며, 특히 PRL/Progesterone의 농도비율이 SLP의 판정에 한 지표가 될 수 있을 것으로 사료된다.

• The Transactions of the Korean Institute of Power Electronics
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• v.8 no.2
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• pp.128-136
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• 2003

This paper investigates the application of the anti-windup scheme to control U voltage of the three-phase four-wire active power filter, installed in a three-phase four-wire power system. In order to reduce efficiently the harmonic currents caused by the switching loads and to improve the whole performance of the flower system, the DC voltage of the three-phase four-wire active power filter should be properly controlled. PI controller can be applied to the U voltage controller of the three-phase four-wire active power filter. However, a large error input to PI controller leads to a windup phenomenon which deteriorate the dynamic characteristics of the U voltage controller Therefore, the application of the anti-windup scheme for the DC voltage controller is proposed and the improved performances of the anti-windup U voltage controller are proved through the computer simulation study.

• Journal of the Korean Ceramic Society
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• v.44 no.9
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• pp.471-476
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• 2007

The hydration mechanism of the $3CaO{\cdot}Al_2O_3-CaSO_4{\cdot}2H_2O$ system in the presence of alkali sulfates has been investigated. The early hydration rate of $3CaO{\cdot}Al_2O_3$ was accelerated by the addition of $Na_2SO_4$ and $K_2SO_4$. This is closely related to the formation of syngenite $(CaSO_4{\cdot}K_2SO_4{\cdot}H_2O)$, and the U-phase added $K_2SO_4$ and $Na_SO_4$ in the $3CaO{\cdot}Al_2O_3-CaSO_4{\cdot}2H_2O$ system, respectively. The formation of the rigid syngenite and U-phase structure led to rapid setting and decreases the sulfate content in the liquid phase of the hydrating cement to the extent that it cannot adequately retard the hydration of $3CaO{\cdot}Al_2O_3$. In case of the alkali sulfate not added to the $3CaO{\cdot}Al_2O_3-CaSO_4{\cdot}2H_2O$ system, the ettringite was transformed to monosulfoaluminate immediately after the consumption of gypsum. However, when the alkali sulfates were added to this system, the ettringite did not transform to monosulfoaluminate immediately even though the gypsum was completely consumed. There was a stagnation period to transform to the monosufoaluminate after the consumption of gypsum because the syngenite and U-phase remained as the sulfate source.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.1
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• pp.200-214
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• 1993

This paper presents the results of fluidelastic instability analysis performed for the U-tube bundle of a Westinghouse model 51 steam generator, one of the recirculating types designed at an early stage, in which the principal region of external cross-flow is associated with the U-bend portion of tube. The prerequisites for this analysis are detailed informations of the secondary side flow conditions in the steam generator and the free vibration behaviours of the U-tubes. In this study, the three-dimensional two-phase flow field in the steam generator has been calculated employing the ATHOS3 steam generator two-phase flow code and the ANSYS engineering analysis code has been used to calculate the free vibration responses of specific U tubes under consideration. The assessment of the potential instability for the suspect U-tubes, which is the final analysis process of the present work, has been accomplished by combining the secondary side velocity and density distributions obtained from the ATHOS3 prediction with the relative modal displacement and natural frequency data calculated using the ANSYS code. The damping of tubes in two-phase flow has been deduced from the existing experimental data by taking into account the secondary side void fraction effect. In operation of the steam generator, the tube support conditions at the tube-to-tube support plate intersections due to either tube denting degradation or deposition of tube support plate corrosion products or ingression of dregs. Thus, various hypothetical cases regarding the tube support conditions at the tube-to-tube support plate intersections have been considered to investigate the clamped support effects on the forced vibration response of the tube. Also, the effect of anti-vibration bars support in the curved portion of tube has been examined.

• Journal of Society of Preventive Korean Medicine
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• v.13 no.3
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• pp.87-99
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• 2009

Objectives : The study was to examine the empirical evidence concerning the effects of massage intervention for the laboring women and to investigate the effect sizes related to the characteristics of intervention. Methods : Meta analysis was performed. A total of 11 trials related to massage intervention between 2000 and 2007 were reviewed. Results : Massage intervention showed a beneficial effect on length of labor(1st stage : U=46.75, p=0.00, 2nd stage : U=6.13, p=0.01), perception of childbirth experience(U=12.57, p=0.00), intensity of uterine contraction at the active(U=6.34, p=0.01) and the transition phases(U=24.83, p=0.00), and interval of uterine contraction at the active phase(U=4.83, p=0.03). Massage decreased systolic(U=10.81, p=0.00) and diastolic blood pressure at the transition phase(U=10.60, p=0.00). However, massage had no effect on subjective and objective labor pain and anxiety. No differences were found in effectiveness of massage according to characteristics of intervention(massage material, massager, and massage site) except for anxiety(QB=4.82, p=0.03) and diastolic blood pressure at the active phase by massage site(QB=4.52, p=0.03). Conclusions :We found that massage intervention for the laboring women had an empirical evidence on improving perception of childbirth experience and shortening length of labor. These results should be interpreted with caution due to the lack of studies. More full-scale randomized clinical trials with reliable designs are recommended to further warrant the effectiveness of massage.

• Journal of Physiology & Pathology in Korean Medicine
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• v.25 no.2
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• pp.189-194
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• 2011

Nardostachys chinensis (N. Chinensis) belonging to the family Valerianaceae have been used in traditional medicine to elicit stomachic and sedative effects. The present study investigated the effects of water extract of N. Chinensis in human lymphoma U937 cells. The proliferation of U937 cells was decreased by N. Chinensis. Anti-proliferative effect of N. Chinensis on U937 cells was associated with G0/G1 phase arrest, which was mediated by regulating the expression of p21 and p27 protein. In addition, the levels of CDK2, CDK4, CDK6, Cyclin D3, and Cyclin A were decreased, but Cyclin D1, Cyclin D2 and Cyclin E were essentially undetectable. N. Chinensis induced the differentiation of U937 as shown by increased expression of differentiation surface antigen CD11b, but not CD14. Taken together, these results demonstrated that N. Chinensis potently inhibits the proliferation of U937 cells via the G0/G1 phase cell cycle arrest in association with p21 and p27, and induces granulocytic differentiation.

• Proceedings of the KIEE Conference
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• 1997.07a
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• pp.41-43
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• 1997

This paper represents the comparison of harmonic loss characteristics of the inverter-driven 3-phase squirrel cage induction motor with slit and U-iron bridge slots of rotor. Two-dimensional time-stepped finite element method is used for electromagenetic field analysis. And spectrums of bar current, phase current, and torque are compared in each case.

• Proceedings of the Materials Research Society of Korea Conference
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• 2008.05a
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• pp.43.1-43.1
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• 2008

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.49 no.8
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• pp.536-543
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• 2000

The photovoltaic power generation system has a great future as clean energy instead of fossil fuel which has many environmental problems such as exhausted gas or air pollution. In a utility interactive photovoltaic generation system, a three-phase inverter is used for the connection between the photovoltaic array and the utility. This paper present a three phase inverter for photovoltaic power system with current controller, voltage controller, PLL Control system and the Phase detector of Interactive Voltage by using dq transformation. The proposed inverter system provides a sinusoidal ac current for domestic loads and the utility line with unity power factor.