Mechanical behavior of stud shear connectors embedded in HFRC

Yu-Liang He,Xu-Dong Wu,Yiqiang Xiang,Yu-Hang Wang,Li-Si Liu,Zhi-Hai He 국제구조공학회 2017 Steel and Composite Structures, An International J Vol.24 No.2

Hybrid-fiber reinforced concrete (HFRC) may provide much higher tensile and flexural strengths, tensile ductility, and flexural toughness than normal concrete (NC). HFRC slab has outstanding advantages for use as a composite bridge potential deck slab owing to higher tensile strength, ductility and crack resistance. However, there is little information on shear connector associated with HFRC slabs. To investigate the mechanical behavior of the stud shear connectors embedded in HFRC slab, 14 push-out tests (five batches) in HFRC and NC were conducted. It was found that the stud shear connector embedded in HFRC had a better ductility, higher stiffness and a slightly larger shear bearing capacity than those in NC. The experimentally obtained ultimate resistances of the stud shear connectors were also compared against the equations provided by GB50017 2003, ACI 318-112011, AISC 2011, AASHTO LRFD 2010, PCI 2004, and EN 1994-1-1 (2004), and an empirical equation to predict the ultimate shear connector resistance considering the effect of the HFRC slabs was proposed and validated by the experimental data. Curve fitting was performed to find fitting parameters for all tested specimens and idealized load-slip models were obtained for the specimens with HFRC slabs.

More precise determination of V_cb & V_ub and direct CP violation in charmless B decays

Yue-liang Wu,Yu-Feng Zhou,YWhen-Yu Wang 한국물리학회 2004 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.45 No.2

More precise extractions on the two important CKM matrix elements jVcbj and jVubj are presented up to 1=m2 Q corrections, based on the complete heavy-quark eective eld theory (HQEFT) of QCD. The HQEFT as a large component QCD provides us with a complete theoretical framework for correctly and systematically evaluating the subleading and higher-order contributions in 1=mQ expansion of heavy quarks. A global analysis on charmless B decays is made, based on the isospin and SU(3) avor symmetry. An isospin relation is found to be very useful for studying SU(3) symmetry-breaking eects of strong phases and exploring new types of electroweak penguin eects. The direct CP violation in charmless B decays is predicted, and its precise measurement is helpful either for testing SU(3) symmetry breaking eects of strong phases or for probing new physics beyond standard model.

Transitional Percentage of Minute Volume as a Novel Predictor of Weaning from Mechanical Ventilation in Patients with Chronic Respiratory Failure

Ya-Ru Liang,Mei-Chen Yang,Yao-Kuang Wu,I-Shiang Tzeng,Pei-Yi Wu,Shiang-Yu Huang,Chou-Chin Lan,Chin-Pyng Wu 한국간호과학회 2020 Asian Nursing Research Vol.14 No.1

Purpose: Some patients with respiratory failure fail initial weaning attempts and need prolonged mechanical ventilation (MV). Prolonged MV is associated with many complications and consumption of heathcare resources. Objective weaning indices help staffs to identify high-potential patients for weaning from the MV. Traditional weaning indices are not reliable in clinical practice. Transitional percentage of minute volume (TMV%) is a new index of the work of breathing. This study aimed to investigate the utility of TMV% in the prediction of weaning potential. Methods: This study was prospectively performed including all patients with prolonged MV. Researchers recorded their demographics, TMV%, respiratory parameters, Acute Physiology and Chronic Health Evaluation II score, and laboratory data upon arrival at the respiratory care center. The factors associated with successful weaning were analyzed. Results: Out of the 120 patients included, 84 (70.0%) were successfully weaned from MV. Traditional weaning indices such as rapid shallow breathing index could not predict the weaning outcome. TMV% was a valuable parameter as patients with a lower TMV%, higher tidal volume, higher hemoglobin, lower blood urea nitrogen, and lower Acute Physiology and Chronic Health Evaluation II scores had a higher rate of successful weaning. TMV%, tidal volume, and HCO3- levels were independent predictors of successful weaning, and the area under the curve was .79 in the logistic regression model. Conclusion: TMV% is a novel and effective predictor of successful weaning. Patients with lower TMV% had a higher MV weaning outcome. Once patients with a high potential for successful weaning are identified, they should be aggressively weaned from MV as soon as possible.

Prediction and Monitoring of the Construction Vibration Effect on an Adjacent Old Long Span Double-Convex Arch Bridge

Yu-xiong Liang,Qing-song Feng,Mei-zhen Fu,Bi-tao Wu,Jian-fei Lu,Guo-xi Tang 대한토목학회 2022 KSCE JOURNAL OF CIVIL ENGINEERING Vol.26 No.5

Ground vibrations caused by the construction of impact drilling piles may affect adjacent bridges, so corresponding prediction and monitoring are necessary to ensure the safety of bridges. In this study, the construction near an existing long-span double-convex arch bridge is taken as a case study to investigate different layouts of construction machines emanating harmful ground vibrations to the existing adjacent bridge by numerical simulations and monitoring. The peak acceleration and velocity acquired from numerical simulations, and monitoring were successfully used to implement impact drilling pile construction near the existing bridge. The results show that there are good consistencies between the monitoring and numerical simulation results, and the vibration acceleration of the foundation of abutments and piers are mainly derived from the vibration caused by the construction within a distance of 50 m, while the construction beyond 50 m has little effect on the old bridge. The numbers and locations of machines near the same foundation may have a weakening or strengthening effect on the peak acceleration and velocity due to destructive and constructive interference of waves, which can help to control the effects of the vibrations of the existing adjacent bridge.

Pretreatment Thrombocytosis as a Prognostic Factor in Women with Gynecologic Malignancies: a Meta-analysis

Yu, Min,Liu, Lei,Zhang, Bing-Lan,Chen, Qi,Ma, Xue-Lei,Wu, Yu-Ke,Liang, Chun-Shui,Niu, Zhi-Min,Qin, Xin,Niu, Ting Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.12

Background: This study was performed to analyze the prognostic implications of pretreatment or preoperative thrombocytosis in women with gynecologic malignancies. Material and Methods: We surveyed 2 medical databases, PubMed and EMBASE, to identified all relevant studies. A total of 14 (n=3,490) that evaluated the link between thrombocytosis and 5-year survival were included. REVMAN version 5.1 was used for our analysis and publication bias was evaluated using the Begg's funnel plot and tested by STATA 11.0. Risk ratios (RRs) with 95% confidence intervals (CIs) generated by the random effect model were used to assess the strength of any association. Results: 709(20.3%) of the 3,490 patients exhibited thrombocytosis (platelet counts > $400{\times}10^9/L$) at primary diagnosis, and their mortality was 1.62-fold higher compared with the others (RR=1.62, 95%CI=[1.28-2.05], p<0.0001). Thrombocytosis failed to have a stronger effect on the survival of advanced patients of stages III to IV in our study (n=478, RR=1.29, 95% CI=[1.13-1.48], p=0.0003), nor in women with cervical cancer in stage IB (n=1371, RR=1.73, 95% CI=[1.71-2.58], p=0.007). In addition, when adjusted for different carcinoma, it was associated with worse prognosis for all except the ones with vulvar cancer (n=201, RR=0.43, 95% CI=[0.14-1.29], p=0.13). Conclusions: This meta-analysis indicated that thrombocytosis might be associated with a worse prognosis for patients with gynecologic malignancies but without specificity or sensitivity for the ones in advanced stage. When adjusted for different gynecologic malignancies, it showed a significant effect on survival of all except vulvar cancers.

An application of quantitative feedback theory in a 3D active vibration isolation platform

Yu-Liang Chung,Meng Shiun Tsai,Jen-Hua Wu 한국소음진동공학회 2003 한국소음진동공학회 국제학술대회논문집 Vol.2003 No.8

Proposals for flexural capacity prediction method of externally prestressed concrete beam

Wu-Tong Yan,Liang-Jiang Chen,Bing Han,Feng Wei,Hui-Bing Xie,Jia-Ping Yu 국제구조공학회 2022 Structural Engineering and Mechanics, An Int'l Jou Vol.83 No.3

Flexural capacity prediction is a challenging problem for externally prestressed concrete beams (EPCBs) due to the unbonded phenomenon between the concrete beam and external tendons. Many prediction equations have been provided in previous research but typically ignored the differences in deformation mode between internal and external unbonded tendons. The availability of these equations for EPCBs is controversial due to the inconsistent deformation modes and ignored secondorder effects. In this study, the deformation characteristics and collapse mechanism of EPCB are carefully considered, and the ultimate deflected shape curves are derived based on the simplified curvature distribution. With the compatible relation between external tendons and the concrete beam, the equations of tendon elongation and eccentricity loss at ultimate states are derived, and the geometric interpretation is clearly presented. Combined with the sectional equilibrium equations, a rational and simplified flexural capacity prediction method for EPCBs is proposed. The key parameter, plastic hinge length, is emphatically discussed and determined by the sensitivity analysis of 324 FE analysis results. With 94 collected laboratory-tested results, the effectiveness of the proposed method is confirmed, and comparisons with the previous formulas are made. The results show the better prediction accuracy of the proposed method for both stress increments and flexural capacity of EPCBs and the main reasons are discussed.

Study of the Optimal Film Structure by Using Conventional Elipsometry

Liang-Yao Chen,Ming-Yu Sheng,Yun-Hua Wu,Yuan Zhao,Yue-Rui Chen,Yu-Xiang Zheng 한국물리학회 2008 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.53 No.2

The optimal film structure affected by the space effect has been studied for SiO2 film samples deposited onto Si wafers by using the e-beam evaporation method. The ellipsometric data were measured at different incidence angles and in the 300-800-nm wavelength range. In the range where the phase delay δ is close to π, the film thickness deduced from the conventional ellipsometry model varied with the phase delay. The optimal SiO2 film-thickness was achieved with a modified ellipsometric model, including the space effect. The results given in this work can generally be applied to other optical measurement methods used to study film structures.

Transformation of Wheat Immature Embryos by Particle Bombardment

Wu Li-Min,Wei Yu-Ming,Zheng You-Liang The Korean Society of Plant Biotechnology 2005 Plant molecular biology and biotechnology research Vol.7 No.2

The objective of this study was to identify the major parameters controlling DNA delivery by particle bombardment to immature embryos of Chinese spring wheat (Triticum aestivum L.). Efficiency of DNA (uidA gene) delivery was assessed by transient GUS (${\beta}$-glucuronidase) expression in bombarded tissues. Of the parameters analyzed, acceleration pressure, bombardment distance, chamber vacuum pressure, bombardment times, osmotic conditioning of culture had a remarkable influence on transient gene expression. A bombardment procedure suitable for Chinese spring wheat cultivars was developed which allowed high-efficiency DNA delivery combined with reduced damage to target tissues. The high efficiency made the system practical for wheat genetic transformation research and accelerating wheat breeding programs.

Design and Implementation of a Photovoltaic Grid-Connected Micro-Inverter with Power Factor Correction Technology

Yu-Kun Chen,Tsorng-Juu Liang,Wei-Chia Wu 전력전자학회 2015 ICPE(ISPE)논문집 Vol.2015 No.6

In this paper, a photovoltaic (PV) girdconnected micro-inverter controlled by power factor correction (PFC) controller is implemented. The PFC controller is adopted to control the inverter output current sinusoidally. Besides, the maximum power point tracking control circuit can get the maximum power form PV modules. The duality between the PFC circuit and the inverter circuit is presented first. Then, the PFC design rules is applied in the inverter circuit. However, the flyback inverter controlled by boundary conduction mode (BCM) PFC IC will cause a high third harmonic component from the analysis. Hence, the third harmonic injection method is estimated and analyzed to improve the output current total harmonic distortion. Finally, a 300W grid-connected flyback micro-inverter with BCM control based on L6561 PFC controller is implemented to verify the feasibility. Input voltage is 20V to 40V and the peak power is 300 W from PV simulator, and the output voltage is 220Vac/60Hz. The highest efficiency of the micro-inverter is 92.8%.