Vibration characteristic analysis of sandwich cylindrical shells with MR elastomer

Jia-Yi Yeh 국제구조공학회 2016 Smart Structures and Systems, An International Jou Vol.18 No.2

The vibration characteristic analysis of sandwich cylindrical shells subjected with magnetorheological (MR) elastomer and constraining layer are considered in this study. And, the discrete finite element method is adopted to calculate the vibration and damping characteristics of the sandwich cylindrical shell system. The effects of thickness of the MR elastomer, constraining layer, applied magnetic fields on the vibration characteristics of the sandwich shell system are also studied in this paper. Additionally, the rheological properties of the MR elastomer can be changed by applying various magnetic fields and the properties of the MR elastomer are described by complex quantities. The natural frequencies and modal loss factor of the sandwich cylindrical shells are calculated for many designed parameters. The core layer of MR elastomer is found to have significant effects on the damping behavior of the sandwich cylindrical shells.

Axisymmetric dynamic instability of polar orthotropic sandwich annular plate with ER damping treatment

Yeh, Jia-Yi Techno-Press 2014 Smart Structures and Systems, An International Jou Vol.13 No.1

The axisymmetric dynamic instability of polar orthotropic sandwich annular plate combined with electrorheological (ER) fluid core layer and constraining layer are studied in this paper. And, the ER core layer and constraining layer are used to improve the stability of the annular plate system. The boundaries of instability regions for the polar orthotropic sandwich annular plate system are obtained by discrete layer annular finite element and the harmonic balance method. The rheological property of an electrorheological material, such as viscosity, plasticity, and elasticity can be controlled by applying different electric field strength. Thus, the damping characteristics of the sandwich system are more effective when the electric field is applied on the sandwich structure. Additionally, variations of the instability regions for the polar orthotropic sandwich annular plate with different applying electric field strength, thickness of ER layer and some designed parameters are investigated and discussed in this study.

Parametric resonance of axisymmetric sandwich annular plate with ER core layer and constraining layer

Yeh, Jia-Yi Techno-Press 2011 Smart Structures and Systems, An International Jou Vol.8 No.5

The parametric resonance problems of axisymmetric sandwich annular plate with an electrorheological (ER) fluid core and constraining layer are investigated. The annular plate is covered an electrorheological fluid core layer and a constraining layer to improve the stability of the system. The discrete layer annular finite element and the harmonic balance method are adopted to calculate the boundary of instability regions for the sandwich annular plate system. Besides, the rheological property of an electrorheological material, such as viscosity, plasticity, and elasticity can be changed when applying an electric field. When the electric field is applied on the sandwich structure, the damping of the sandwich system is more effective. Thus, variations of the instability regions for the sandwich annular plate with different applying electric fields, thickness of ER layer, and some designed parameters are presented and discussed in this study. The ER fluid core is found to have a significant effect on the location of the boundaries of the instability regions.

Parametric resonance of axisymmetric sandwich annular plate with ER core layer and constraining layer

Jia-Yi Yeh 국제구조공학회 2011 Smart Structures and Systems, An International Jou Vol.8 No.5

The parametric resonance problems of axisymmetric sandwich annular plate with an electrorheological (ER) fluid core and constraining layer are investigated. The annular plate is covered an electrorheological fluid core layer and a constraining layer to improve the stability of the system. The discrete layer annular finite element and the harmonic balance method are adopted to calculate the boundary of instability regions for the sandwich annular plate system. Besides, the rheological property of an electrorheological material, such as viscosity, plasticity, and elasticity can be changed when applying an electric field. When the electric field is applied on the sandwich structure, the damping of the sandwich system is more effective. Thus, variations of the instability regions for the sandwich annular plate with different applying electric fields, thickness of ER layer, and some designed parameters are presented and discussed in this study. The ER fluid core is found to have a significant effect on the location of the boundaries of the instability regions.

Axisymmetric dynamic instability of polar orthotropic sandwich annular plate with ER damping treatment

Jia-Yi Yeh 국제구조공학회 2014 Smart Structures and Systems, An International Jou Vol.13 No.1

The axisymmetric dynamic instability of polar orthotropic sandwich annular plate combinedwith electrorheological (ER) fluid core layer and constraining layer are studied in this paper. And, the ERcore layer and constraining layer are used to improve the stability of the annular plate system. Theboundaries of instability regions for the polar orthotropic sandwich annular plate system are obtained bydiscrete layer annular finite element and the harmonic balance method. The rheological property of anelectrorheological material, such as viscosity, plasticity, and elasticity can be controlled by applying differentelectric field strength. Thus, the damping characteristics of the sandwich system are more effective when theelectric field is applied on the sandwich structure. Additionally, variations of the instability regions for thepolar orthotropic sandwich annular plate with different applying electric field strength, thickness of ER layerand some designed parameters are investigated and discussed in this study.

High-Performance Bottom-Contact Organic Thin-Film Transistors Based on Benzo[<i>d</i>,<i>d</i>′]thieno[3,2-<i>b</i>;4,5-<i>b</i>′]dithiophenes (BTDTs) Derivatives

Huang, Peng-Yi,Chen, Liang-Hsiang,Kim, Choongik,Chang, Hsiu-Chieh,Liang, You-jhih,Feng, Chieh-Yuan,Yeh, Chia-Ming,Ho, Jia-Chong,Lee, Cheng-Chung,Chen, Ming-Chou American Chemical Society 2012 ACS APPLIED MATERIALS & INTERFACES Vol.4 No.12

<P>Three benzo[<I>d</I>,<I>d</I>′]thieno[3,2-<I>b</I>;4,5-<I>b</I>′]dithiophene (<B>BTDT</B>) derivatives, end-functionalized with benzothiophenyl (<B>BT-BTDT</B>; <B>2</B>), benzothieno[3,2-b]thiophenyl (<B>BTT-BTDT</B>; 3), and benzo[<I>d</I>,<I>d</I>′]thieno[3,2-<I>b</I>;4,5-<I>b</I>′]dithiophenyl (<B>BBTDT</B>; <B>4</B>), were prepared for bottom-contact/bottom-gate organic thin-film transistors (OTFTs). An improved one-pot [2 + 1 + 1] synthetic method of <B>BTDT</B> with improved synthetic yield was achieved, which enabled the efficient realization of new <B>BTDT</B>-based semiconductors. All of the <B>BTDT</B> compounds exhibited high performance p-channel characteristics with carrier mobilities as high as 0.34 cm<SUP>2</SUP>/(V s) and a current on/off ratio of 1 × 10<SUP>7</SUP>, as well as enhanced ambient stability. The device characteristics have been correlated with the film morphologies and microstructures of the corresponding compounds.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/aamick/2012/aamick.2012.4.issue-12/am3022448/production/images/medium/am-2012-022448_0010.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/am3022448'>ACS Electronic Supporting Info</A></P>

Comedications and potential drug-drug interactions with direct-acting antivirals in hepatitis C patients on hemodialysis

( Po-yao Hsu ),( Yu-ju Wei ),( Jia-jung Lee ),( Sheng-wen Niu ),( Jiun-chi Huang ),( Cheng-ting Hsu ),( Tyng-yuan Jang ),( Ming-lun Yeh ),( Ching-i Huang ),( Po-cheng Liang ),( Yi-hung Lin ),( Ming-ye 대한간학회 2021 Clinical and Molecular Hepatology(대한간학회지) Vol.27 No.1

Background/Aims: Direct-acting antivirals (DAAs) have been approved for hepatitis C virus (HCV) treatment in patients with end-stage renal disease (ESRD) on hemodialysis. Nevertheless, the complicated comedications and their potential drug-drug interactions (DDIs) with DAAs might limit clinical practice in this special population. Methods: The number, class, and characteristics of comedications and their potential DDIs with five DAA regimens were analyzed among HCV-viremic patients from 23 hemodialysis centers in Taiwan. Results: Of 2,015 hemodialysis patients screened in 2019, 169 patients seropositive for HCV RNA were enrolled (mean age, 65.6 years; median duration of hemodialysis, 5.8 years). All patients received at least one comedication (median number, 6; mean class number, 3.4). The most common comedication classes were ESRD-associated medications (94.1%), cardiovascular drugs (69.8%) and antidiabetic drugs (43.2%). ESRD-associated medications were excluded from DDI analysis. Sofosbuvir/velpatasvir/voxilaprevir had the highest frequency of potential contraindicated DDIs (red, 5.6%), followed by glecaprevir/pibrentasvir (4.0%), sofosbuvir/ledipasvir (1.3%), sofosbuvir/velpatasvir (1.3%), and elbasvir/grazoprevir (0.3%). For potentially significant DDIs (orange, requiring close monitoring or dose adjustments), sofosbuvir/velpatasvir/voxilaprevir had the highest frequency (19.9%), followed by sofosbuvir/ledipasvir (18.2%), glecaprevir/pibrentasvir (12.6%), sofosbuvir/velpatasvir (12.6%), and elbasvir/grazoprevir (7.3%). Overall, lipid-lowering agents were the most common comedication class with red-category DDIs to all DAA regimens (n=62), followed by cardiovascular agents (n=15), and central nervous system agents (n=10). Conclusions: HCV-viremic patients on hemodialysis had a very high prevalence of comedications with a broad spectrum, which had varied DDIs with currently available DAA regimens. Elbasvir/grazoprevir had the fewest potential DDIs, and sofosbuvir/velpatasvir/voxilaprevir had the most potential DDIs. (Clin Mol Hepatol 2021;27:186-196)