• 제목/요약/키워드: Science and Technology University

검색결과 76,446건 처리시간 0.091초

VIBRATION SIGNAL ANALYSIS OF MAIN COOLANT PUMP FLYWHEEL BASED ON HILBERT-HUANG TRANSFORM

  • LIU, MEIRU;XIA, HONG;SUN, LIN;LI, BIN;YANG, YANG
    • Nuclear Engineering and Technology
    • /
    • 제47권2호
    • /
    • pp.219-225
    • /
    • 2015
  • In this paper, a three-dimensional model for the dynamic analysis of a flywheel based on the finite element method is presented. The static structure analysis for the model provides stress and strain distribution cloud charts. The modal analysis provides the basis of dynamic analysis due to its ability to obtain the natural frequencies and the vibration-made vectors of the first 10 orders. The results show the main faults are attrition and cracks, while also indicating the locations and patterns of faults. The harmonic response simulation was performed to gain the vibration response of the flywheel under operation. In this paper, we present a Hilbert-Huang transform (HHT) algorithm for flywheel vibration analysis. The simulation indicated that the proposed flywheel vibration signal analysis method performs well, which means that the method can lay the foundation for the detection and diagnosis in a reactor main coolant pump.

Highly Active Electrocatalyst based on Ultra-low Loading of Ruthenium Supported on Titanium Carbide for Alkaline Hydrogen Evolution Reaction

  • Junghwan, Kim;Sang-Mun, Jung;Kyu-Su, Kim;Sang-Hoon, You;Byung-Jo, Lee;Yong-Tae, Kim
    • Journal of Electrochemical Science and Technology
    • /
    • 제13권4호
    • /
    • pp.417-423
    • /
    • 2022
  • With the emerging importance of catalysts for water electrolysis, developing efficient and inexpensive electrocatalysts for water electrolysis plays a vital role in renewable hydrogen energy technology. In this study, a 1nm thickness of TiC-supported Ru catalyst for hydrogen evolution reaction (HER) has been successfully fabricated using an electron (E)-beam evaporator and thermal decomposition of gaseous CH4 in a furnace. The prepared Ru/TiC catalyst exhibited an outstanding performance for alkaline hydrogen evolution reaction with an overpotential of 55 mV at 10 mA cm-2. Furthermore, we demonstrated that the outstanding HER performance of Ru/TiC was attributed to the high surface area of the support and the metal-support interaction.

Intravenous administration of L-tryptophan stimulates gastrointestinal hormones and melatonin secretions: study on beef cattle

  • Lee, Sang-Bum;Lee, Kyung-Won;Wang, Tao;Lee, Jae-Sung;Jung, U-Suk;Nejad, Jalil Ghassemi;Oh, Young-Kyoon;Baek, Youl-Chang;Kim, Kyoung Hoon;Lee, Hong-Gu
    • Journal of Animal Science and Technology
    • /
    • 제61권4호
    • /
    • pp.239-244
    • /
    • 2019
  • This study aimed to determine the effective dose of intravenous administration of L-tryptophan (L-T) on gastrointestinal hormones (GIH) secretions and melatonin using Hanwoo cattle. Three steers ($362{\pm}23kg$) fitted with indwelling jugular vein catheters were assigned in a $3{\times}3$ Latin square design. Treatments were intravenous administration of saline (control), 28.9 mg L-T/kg body weight (BW; low) and 57.8 mg L-T/kg BW (high) L-T for 1 day with 7 days of adaptation. Samples were collected after adaptation period at -60, 0, 30, 60, 90, 120, 150, 180, 240, and 300 min of sampling day. The levels of serum cholecystokinin (CCK) and secretin were higher (p < 0.05) in the high L-T group than those in the other groups. Serum Melatonin (MEL) levels were increased upon L-T administration (p < 0.05) in the high L-T group. Taken together, the effective dose of L-T administration was defined at 57.8 mg L-T/kg BW in order to stimulate increase of GIH and MEL.

Applications of 5G and 6G in Smart Health Services

  • Al-Jawad, Fatimah;Alessa, Raghad;Alhammad, Sukainah;Ali, Batoola;Al-Qanbar, Majd;Rahman, Atta-ur
    • International Journal of Computer Science & Network Security
    • /
    • 제22권3호
    • /
    • pp.173-182
    • /
    • 2022
  • Healthcare organizations are overwhelmingly embracing smart value-based care strategies, which focuses on providing superior treatment at a significantly lower cost and quality of service (QoS). For these purposes, fifth generation (5G) of mobile service provides an innumerable improvement that clearly outperforms previous generations e.g., 3G and 4G. However, as with most advancements, 5G is projected to introduce new challenges, prompting the community to think about what comes next. This research was conducted to examine the most recent smart 5G technology applications and the solutions they provide to the healthcare industry. Finally, the paper discusses how the upcoming 6G technology has the potential to transform the future of healthcare sector even beyond the current 5G systems.

Synthesis and Characterization of Acrylic Polymer Containing Silk Protein

  • Zhongmin Chen;Kim, Mutsumi ura;Masahiro Suzuki;Yoshiyuki Kondo;Kenji Hanabusa;Hirofusa Shirai
    • 한국섬유공학회:학술대회논문집
    • /
    • 한국섬유공학회 2003년도 The Korea-Japan Joint Symposium
    • /
    • pp.87-87
    • /
    • 2003
  • Three kinds of acrylic polymers containing silk protein were synthesized, which are (1) blending of silk fibroin (SF) fiber and polyacrylonitrile (PAN); (2) graft-copolymer of PAN onto SFs; (3) random-copolymer synthesized by copolymerization of acrylonitrile (AN) and silk fibroin peptide (SFP) with vinyl groups, and their solubility, thermal property, and moisture absorption was investigated, respectively. These polymers have difference solubility and attributable to their structure. Their excellent thermal stabilities and better moisture absorptions were indicated.

  • PDF