• Title/Summary/Keyword: Secondary position

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Stress Analysis of Steam Generator Row-1 Tubes (증기발생기 제1열 전열관의 응력 해석)

  • Kim, Woo-Gon;Ryu, Woo-Seog;Lee, Ho-Jin;Kim, Sung-Chung
    • Proceedings of the KSME Conference
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    • 2000.04a
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    • pp.25-30
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    • 2000
  • Residual stresses induced in U-bending and tube-to-tubesheet joining processes of PWR's steam generator row-1 tube were measured by X-ray method and Hole-Drilling Method(HDM). The stresses resulting from the Internal pressure and the temperature gradient in the steam generator were also estimated theoretically. In U-bent lesions, the residual stresses at extrados were induced with compressive stress(-), and its maximum value reached -319 MPa in axial direction at ${\psi}=0^{\circ}$ in position. Maximum tensile residual stress of 170MPa was found to be at the flank side at Position of${\psi}=90^{\circ}$, i.e., at apex region. In tube-to-tubesheet fouling methods, the residual stresses induced by the explosive joint method were found to be lower than that by the mechanical roll method. The gradient of residual stress along the expanded tube was highest at the. transition region, and the residual stress in circumferential direction was found to be higher than the residual stress in axial direction. Hoop stress due to an internal pressure between primary and secondary side was analyzed to be 76 MPa and thermal stress was 45 MPa.

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Designing An Effective siRNA (효과적인 siRNA의 디자인)

  • Gu, Nam-Jin;Jo, Gwang-Hwi
    • Bioinformatics and Biosystems
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    • v.2 no.1
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    • pp.17-23
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    • 2007
  • Shot interfering RNA (siRNA) can be used to silence specific gene expression and have many potential therapeutic applications. However, how to design an effective siRNA is still not clear. Highly effective siRNA has sequence-specific properties which are low G/C content, low internal stability at the sense strand 3'-terminus, sense strand base bias(position 1 is G/C, position 19 is /AU). Recently, mRNA secondary structure playsan important role in RNAi. Target site of siRNA in high-ordered structure (i.e hairpin loop, multi loop) or base pair of many hydrogen bonds dramatically reduce function of siRNA mediated gene silencing. Possible off-target effects of siRNA is detecting from BLAST search.

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Relationship between Autonomy and Job Satisfaction of the Hospital Nurses (병원 간호사의 자율성과 직무만족도와의 관계)

  • Kang, Young-Sook;Cho, Gyoo-Yeong
    • The Korean Journal of Health Service Management
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    • v.6 no.2
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    • pp.45-56
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    • 2012
  • The purpose of this study was to investigates the Autonomy and Job Satisfaction of the Nurses. The data was collected by distributing structured questionnaires to 317 nurses in 4 secondary hospitals located in Pusan, from July 1 to 31, 2010 and analyzed by t-test, ANOVA, Pearson correlation coefficient. The average autonomy level of nursing professionals was $135.30{\pm}8.04$ points. The average nurse's job satisfaction was $3.12{\pm}.35$ points. There was significant difference according to age, career and position in autonomy level of nursing professionals. There was significant difference according to age, marital status, career, position and monthly income in nurse's job satisfaction. The correlation between autonomy and job satisfaction of the nurses showed to be positively correlated at r = .426. Therefore, It is necessary to research into the methods to enhance the autonomy levels of nursing professionals and nurse's job satisfaction. It is necessary to develop education and policy programs for nurse's autonomy and nurse's job satisfaction.

Augmentation of Heat Transfer for Circular Water Jet Impinging on a Cylindrical Inner Surface (충돌수분류(衝突水噴流)에 의한 원통내면(圓筒內面)에서의 열전달증진(熱傳達增進)에 관한 연구(硏究))

  • Ohm, K.C.;Woo, C.K.;Choi, G.G.;Seo, J.Y.
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.2 no.4
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    • pp.279-287
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    • 1990
  • An experimental study of the heat transfer characteristics between circular water jet and cylindrical inner surface is presented. The ratios of the semi-cylinder's inner diameter and the nozzle outlet diameter were varied parametrically, as were the Reynolds number and the supplementary water heights. The measurements showed that cirucmferential distribution of the heat transfer coefficient peaked at the stagnation point and, there occurred a kind of a secondary maximum of heat transfer that moved toward to stagnation point as the ratio d/D increased. The local heat transfer coefficient increases as the Reynolds number becomes larger, and the rate of increase is subjected to the influence of d/D & position of angle. Also, optimum heights of supplementary water which brings about the augmentation of heat transfer are S/D=1 for the stagnation point, the position of $15^{\circ}$ & $30^{\circ}$ angle, but for the positions of $45^{\circ}$ angle (d/D=10~11.67), $60^{\circ}$ & $75^{\circ}$ angle, the heat transfer coefficients in the case of using supplementary water are smaller than simple jet (S/D=0).

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LATITUDINAL DISTRIBUTION OF SUNSPOTS AND DURATION OF SOLAR CYCLES

  • CHANG, HEON-YOUNG
    • Journal of The Korean Astronomical Society
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    • v.48 no.6
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    • pp.325-331
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    • 2015
  • We study an association between the duration of solar activity and characteristics of the latitude distribution of sunspots by means of center-of-latitude (COL) of sunspots observed during the period from 1878 to 2008 spanning solar cycles 12 to 23. We first calculate COL by taking the area-weighted mean latitude of sunspots for each calendar month to determine the latitudinal distribution of COL of sunspots appearing in the long and short cycles separately. The data set for the long solar cycles consists of the solar cycles 12, 13, 14, 20, and 23. The short solar cycles include the solar cycles 15, 16, 17, 18, 19, 21, and 22. We then fit a double Gaussian function to compare properties of the latitudinal distribution resulting from the two data sets. Our main findings are as follows: (1) The main component of the double Gaussian function does not show any significant change in the central position and in the full-width-at-half-maximum (FWHM), except in the amplitude. They are all centered at ~ 11° with FWHM of ~ 5°. (2) The secondary component of the double Gaussian function at higher latitudes seems to differ in that even though their width remains fixed at ~ 4°, their central position peaks at ~ 22.1° for the short cycles and at ~ 20.7° for the long cycles with quite small errors. (3) No significant correlation could be established between the duration of an individual cycle and the parameters of the double Gaussian. Finally, we conclude by briefly discussing the implications of these findings on the issue of the cycle 4 concerning a lost cycle.

Development of Tomato Harvesting Robot - 3-D Detection Technique for identifiying Tomatoes - (토마토 수확로봇 개발 -토마토의 3차원 위치검출기술-)

  • 손재룡;강창호;한길수;정성림;권기영
    • Journal of Biosystems Engineering
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    • v.25 no.5
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    • pp.415-420
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    • 2000
  • It is very difficult to mechanize tomato harvesting because identifying a target tomato which is partly covered by leaves and stalks is not easy. This research was conducted to develop tomato harvesting robot which can identifying a target tomato, determining its dimensional position, and harvesting it in a limited time. Followings were major findings in this study. The first visual system of the robot was composed of two CCD cameras, however, which could not detect tomato not placed on the center of lens and partly covered by leaves or stalks. Secondary visual device, combined with two cameras and pan tilting was designed which could decreased the positioning errors within $\pm$10mm but still not enough for covered tomato by any obstacles. Finally, laser detector was added to the visual system that could reduce the position detecting errors within 10mm in X-Y direction and 5mm in Z direction for the covered tomatoes.

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Wig usage investigation which symbolizes the socio-economic status (Egypt$\sim$17C)

  • Jung, Hyun-Jin;Kim, Sung-Nam
    • Journal of Fashion Business
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    • v.9 no.6
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    • pp.56-70
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    • 2005
  • This study investigates historically difference by age of wig banishments that symbolize social-economic status from West Egypt era baroque age as qualitative study that use secondary bibliographic data, there is purpose. Conclusion of this study is as following. Because wig putting on that symbolize among several usages of wig putting on, socio-economic status until 17th century baroque age from ancient Egypt is been in fashion through privilege class lower classes as well as upper class wig putting on attain. Ancient wig putting on became measure that divide class because differ material of wig or one dimension, shape (style) and length became linear measure that it can aim wealth's emblem that putting on of long wave wig and whole wig that differ lust has many wig though was in fashion though whole wig and were in fashion arriving to Renaissance. That it becomes France clean fingernails' necessaries as Louis the 14th that ready crux of absolute authority establishment of France Court put wig from depilation to count 17 was clear socio-economic status etc. symbol measure inclination. Go without question status or position, wealth and churchman puts wig so that can know special sex of weapon of where the soldiers are belonged as well as put wig and wig putting on was parted according to job and lower classes participated in fashion of wig putting on. Wig putting on that become measure that symbolize job or status in this baroque age, position, wealth etc. gave absolute influence in wig fashion in 18th century.

An Investigation on Separation Configurations in Compressor Cascades with Boundary Layer Suction(BLS)

  • Zhang, Hualiang;Tan, Chunqing;Zhang, Dongyang;Wang, Songtao;Wang, Zhongqi
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2008.03a
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    • pp.143-149
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    • 2008
  • A numerical study was performed for a vane of a compressor with a high-turning angle and meridional divergence. At first, the effect of the suction position was discussed. Then, the optimal suction position was applied to the cascades with the aspect ratio of 2.53 and 0.3, respectively, to get the knowledge of the effect of the endwall boundary layer removal on the secondary flow along the blade height. At last, using the critical principles of the three-dimensional separation, the topological structures of the flow patterns of the body surfaces and the separation configurations were discussed in detail. The results show that the largest reduction of the total loss can be achieved when the suction slot is near the suction side. The topological structure as well as the separation configuration varies due to boundary layer removal, which restrains the flow separation at the corner and delays or depresses the separation on the suction surface. Compared with the original cascade, the cascade with the endwall boundary layer removal has a higher blade loading along the most span. Furthermore the flow loss decreases and distributes uniformly along the span.

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Pulmonary Function Index Comparisons Depending on Various Postures of Stroke Patients

  • Lee, Kyung-Soo;Lee, Myung-Mo
    • Journal of the Korean Society of Physical Medicine
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    • v.14 no.1
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    • pp.43-51
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    • 2019
  • PURPOSE: To prevent secondary complications from decreased pulmonary functions and promote neurological recovery, identification of respiratory capacity change patterns depending on different postures of stroke patients and investigation of their properties are needed for active rehabilitation. Therefore, this study was conducted to investigate the changes in vital capacity in response to different positions and to implement the results as clinical data. METHODS: A respiratory function test was administered to 52 patients with stroke in the sitting, supine, paretic side lying, and non-paretic side lying positions. Pulmonary function indexes used for comparison were forced vital capacity (FVC), forced expiratory volume at 1 second (FEV1), forced expiratory flow 25-75% (FEF 25-75%), and maximum voluntary ventilation (MVV). One-way repeated ANOVA was used for analysis, and post hoc analysis was conducted using least significant difference (LSD). RESULTS: All pulmonary function indexes were measured in the order of sitting, paretic side lying, supine, and non-paretic side lying positions. Excluding the FEF25-75% and MVV of the supine compared with the paretic side lying position, all other pulmonary function indexes differed significantly (p<.05). CONCLUSION: There are differences in pulmonary function indexes depending on different postures of stroke patients, and the study showed that the non-paretic side lying position yielded the greatest effect on lung ventilation mechanisms. Based on these results, appropriate postures need to be considered during physical therapy interventions for stroke patients.

Aerodynamic analysis of cambered blade H-Darrieus rotor in low wind velocity using CFD

  • Sengupta, Anal Ranjan;Biswas, Agnimitra;Gupta, Rajat
    • Wind and Structures
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    • v.33 no.6
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    • pp.471-480
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    • 2021
  • This present paper leads to investigation of blade-fluid interactions of cambered blade H-Darrieus rotor having EN0005 airfoil blades using comprehensive Computational Fluid Dynamics (CFD) analysis to understand its performance in low wind streams. For several blade azimuthal angle positions, the effects of three different low wind speeds are studied regarding their influence on the blade-fluid interactions of the EN0005 blade rotor. In the prevailing studies by various researchers, such CFD analysis of H-Darrieus rotors are very less, hence it is needed to improve their steady-state performance in low wind velocities. Such a study is also important to obtain important performance insights of such thin cambered blade rotor in its complete rotational cycle. It has been seen that the vortex generated at the suction side of the EN0005 blade rolls back to its leading edge due to the camber of the blade and thus a peak velocity occurs near to the nose position of this blade at its leading edge, which leads to peak performance of this rotor. Again, in the returning phase of the blade, a secondary recirculating vortex is generated that acts on the pressure side of EN0005 blade rotor that increases the performance of this cambered EN0005 blade rotor in its downstream position as well. Here, the aerodynamic performances have been compared considering Standard k-ε and SST k-ω models to check the better suited turbulence model for the cambered EN0005 blade H-Darrieus rotor in low tip speed ratios.