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This paper solves the modified-Duffing ordinary differential equation for large-amplitude vibration of imperfect angle-ply rectangular composite plate. Viscous damping is then introduced in the derivation and analyzed under four different boundary conditions (combining two out-of-plane boundary conditions with two in-plane boundary conditions). It has been shown that even a small viscous damping factor, for example 0.1 from an ordinary damped system can largely decrease the vibration amplitude within several periods. Yet at the same time, the vibration frequency only changes slightly. Furthermore, viscous damping is proved to significantly affect the vibration frequency and the vibration mode from nonlinear to much more linear. This effect is irrelevant to boundary conditions and geometric imperfections.

Studying hydrogen absorption/ desorption in metal-H₂ reactors is important for the usage and commercialization of hydrogen energy. In this article, we present a numerical method for simulating hydrogen absorption in a cylindrical LaNi₅-H₂ reactor. The method is obtained based on the modified heat and mass transfer model for the absorption of hydrogen, and its finite difference approximation in a staggered mesh. As a result, the numerical scheme is unconditionally stable and the solution is second-order accurate. Numerical results including gas and solid densities, gas velocity, gas and solid temperatures are obtained.

Owing to limit in transportation and production, the connection of FRP rebars is an unavoidable problem. A coaxial joining scheme for FRP rebars using winding wet fabrics and fiber bundle/belt composite is presented in this paper. The experimental results indicate that the connection method is effective. And it has the following characteristics: small size, light weight, high strength, corrosion resistance, easy to construction etc. Facing the development of the engineering application in the future, some works need further research are putting forward.

In the work, the comparative analysis geometrical model of a transitional site of thread in structure of a woven fabric of a plain wave is resulted. Key parameters of an arrangement of threads in structure of a woven fabric are determined in view of crumple deformation up to the ellipse form of cross-section of a thread. The technology of their calculation is offered. The work could be expanded to industrial fabrics. Suggestion of the technology calculating of the ground parameters of threads disposition in structure of woven fabric are original and have a major contribution to textile science and technology.

The aim of this study was to determine the effects of two popular web-forming technologies, viz., the Rando air-laid technology and the traditional carding and cross-laying technology, on properties of the hydroentangled nonwoven fabrics made therewith. A mill-like fiber processing study was conducted in a commercial-grade pilot plant using a variety of short staple fibers and their blends. The fibers used in the study were greige cotton, bleached cotton, cotton derivatives, and cut-staple polyester. The hydroentangled fabrics produced with the two systems were mainly evaluated for their physical and mechanical properties, absorbency, absorbency capacity, and whiteness. The study has shown that, with the exception of greige cotton linters, the greige cotton lint, greige cotton gin motes, and even greige cotton comber noils, either alone or in blend with the other fibers mentioned, can be mechanically processed into hydroentangled nonwoven fabric structures without any insurmountable difficulties. The drop test and sink time followed each other pretty closely, as the drop test time increased so did the sink times. The "whiteness" of fabric, which is significantly more dependent on the fabric's constituent fiber content than on the fabric's surface-based light reflection, obviously varied considerably. However, the whiteness index within the same fiber types and their blends shows no trend of significant difference between the fabric produced with carded fiber web and the fabric produced with random Rando fiber web. Incidentally, the Rando sample of bleached cotton was not available. Since the nonwoven fabrics of this discussion generally are disposable, the optional use of ‘brighteners’ to improve whiteness of certain whiteness-deficient fabrics may be considered as long as the brighteners do not easily bleed from the fabrics.

This paper solves the modified-Duffing ordinary differential equation for the largeamplitude vibration problem of imperfect angle-ply laminated rectangular plate. Two inplane and two out-of-plane constraints are considered to form four boundary conditions. The initial condition is chosen to be initial vibration amplitude. To solve this angle-ply laminated rectangular plate vibration problem, Lindstedt’s perturbation technique and Runge-Kutta method are applied. The solution from both methods are plotted and compared for a validity check. Lindstedt’s perturbation technique is proved to be accurate for a sufficiently small vibration amplitude especially when imperfection exists. The results from Runge-Kutta method are plotted to form the typical backbone curves.

This paper deals with the solution of modified-Duffing ordinary differential equation for large-amplitude vibration of imperfect angle-ply rectangular composite plates. The boundary condition is simply supported and in-plane movable. The initial condition for the vibration is an initial vibration amplitude. This vibration problem is solved numerically by Runge-Kutta method. The effect of plate imperfection is studied and proved that a typical backbone curve will show up in case of a relatively large imperfection. Three different composite materials are then chosen to reveal the influence of young’s modulus ratio. Four fiber volumes are assumed to study its effect on the vibration mode. It turns out that either increasing the fiber strength or increasing the fiber volume in a composite will lead to an increase of its overall strength. And this will further trigger the plate vibration to behave more nonlinearly.

This paper describes a new approach for the design of multilayer reinforcements of textile composite materials and products. We offer an alternative to multilayer complex fabrics for which the laminates of the composite reinforcement material consist of orthogonal woven fabrics with an original variable structure when each fabric layer is composed of alternating one‐ply (one warp and one weft) and one and‐ a‐half‐ply (one warp and two wefts) sections. Combination of these sections produces a “gearing” effect, preventing the delamination of textile composites in the process of their exploitation. An important aspect of the proposed method is a possibility to design woven fabrics in concurrence with the dimensions of the composite product and conditions of its exploitation; this leads to a substantial improvement of many properties of such composite product.

China looks set to become the fourth largest outbound tourist generating country in the world by 2020 (World Tourism Organisation, 1997). Tourists from Mainland China are the second most important source of tourist arrivals in Singapore. A better understanding of the Chinese tourists’ needs and expectations will be helpful in positioning the country to attract them. The data collected at Singapore Changi International Airport are segmented to different groups under various demographic factors. This study shows that there exist motivational differences among gender, income, age as well as travel frequencies. The findings are useful to the marketers to establish their strategic plans in targeting at different groups of Chinese visitors.

Polymeric nanocomposite films from PEDOT and MEH-PPV embedded with surface modified TiO₂ nanoparticles were prepared, respectively for the hole transport layer (HTL) and emission layer (EL) in Organic Light Emitting Diodes (OLED). The composite of MEH-PPV + nc-TiO₂ was used for Organic Solar Cells (OCS). The results from the characterization of the properties of the nanocomposites and devices showed that electrical (I-V characteristics) and spectroscopic (photoluminescent) properties of the conjugate polymers were enhanced due to the incorporation of nc-TiO₂ in the polymers. The OLEDs made from the nanocomposite films would exhibit a larger photonic efficiency and a longer lasting life. For the OSC made from MEH-PPV + nc-TiO₂ composite, the fill factor (FF) reached a value as high as 0.34. Under illumination of light with a power density of 50 mW/cm², the photoelectrical conversion efficiency (PEC) was found to be of 0.15% corresponding to an open circuit voltage V_OC = 1.15 V and a short-cut circuit current density J_SC = 0.125 mA/cm².