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This paper presents an instantaneous analysis shadow moire method for dynamic out-of-plane displacement measurement. The shadow moire method is widely applied to the measurement of the out-of-plane displacement, such as the deformation or warpage on the surface of the objects. Generally, the method of phase shifting is used to analyze the phases of the shadow moire fringes and to obtain the out-of-plane displacement. To generate accurate phase shifting, the grating must be moved step by step precisely. However, the step motion provided by the conventional mechanical device is neither accurate nor prompt. In this study, a novel stair-structured plate consisting of a series of 4-step-height sets is designed to produce shadow moire fringes with the quadrature phase. The quadrature-phase fringes are utilized to extract instantaneously the shadow moire phase for measurement of the dynamic out-of-plane displacement of an object. Experiments show that our method can effectively detect the dynamic out-of-plane displacement with a micrometric scale resolution and is capable of suppressing the discrepancy of displacement to 0.83 $$\%$$ . The proposed measurement method of the out-plane displacement is suitable for the pressure sensing or application of the tactile sensor.

A light-mixing module consisting of a compound parabolic concentrator (CPC) and a light-mixing tube is proposed herein to realize a uniform and efficient solar-lighting system. In this lighting system, the sunlight collected into a fiber and then guided to an indoor destination is the principal light source, while an auxiliary light source including multiple red, green, blue, and white (RGBW) light-emitting diodes (LEDs) is controlled by an auto-compensating module. To mix the principal and the auxiliary sources and to realize the uniform illumination, the light-mixing tube was coated with BaSO4 and optimized as a cylindrical tube. The design of the light-mixing tube is described and discussed in this article. According to the simulated results, the uniformity and the optical efficiency of the designed light-mixing tube are 82.9% and 85.7%, respectively, while from the experimental results, the uniformity of 85.9% and the optical efficiency of 83.3% have been obtained. In terms of the common indoor-lighting standards and the specifications of commercial components used in lighting systems, the proposed light-mixing module has demonstrated the high uniformity and acceptable optical efficiency. Additionally, since the main components of the light-mixing module can be designed as plastic optics, a cost-effective light-mixing module and a profitable lighting system can be realized. Thus, the performance and the price of the proposed light-mixing module fit the demands of the illumination market, while the proposed system shows the potential for indoor solar-lighting applications.

This paper proposes an optimal regional pole placement approach for sun tracking control of high-concentration photovoltaic systems. A static output feedback controller is designed to minimize an LQG cost function with a sector region pole constraint. The problem cannot be solved by LMI approach since it is a non-convex optimization problem. Based on the barrier method, we instead solve an auxiliary minimization problem to obtain an approximate solution. Simulation results show the benefit of our approach. Copyright © 2010 John Wiley & Sons, Ltd.

Biomimetic nanostructures have shown to enhance the optical absorption of Ga₀.₅In₀.₅P/GaAs/Ge triple junction solar cells due to excellent antireflective (AR) properties that, however, are highly dependent on their geometric dimensions. In practice, it is challenging to control fabrication conditions which produce nanostructures in ideal periodic arrangements and with tapered side-wall profiles, leading to sacrificed AR properties and solar cell performance. In this work, we introduce compound biomimetic nanostructures created by depositing a layer of silicon dioxide (SiO₂) on top of titanium dioxide (TiO₂) nanostructures for triple junction solar cells. The device exhibits photogenerated current and power conversion efficiency that are enhanced by ~8.9% and ~6.4%, respectively, after deposition due to their improved antireflection characteristics. We further investigate and verify the optical properties of compound structures via a rigorous coupled wave analysis model. The additional SiO₂ layer not only improves the geometric profile, but also serves as a double-layer dielectric coating. It is concluded that the compound biomimetic nanostructures exhibit superior AR properties that are relatively insensitive to fabrication constraints. Therefore, the compound approach can be widely adopted for versatile optoelectronic devices and applications.

A new name, Schismatoglottis kotoensis (Hayata) T. C. Huang, A. Hsiao et H. Y. Yeh,. (Araceae) is proposed for the Flora of Taiwan. Photos of its habitat in nature and detailed line drawings of the floral parts are provided in addition to the description.

In the present study, arsanical-based affinity chromatography for pyruvate kinase (PK) isolation was explored. p -Arsanilic acid (4-aminophenyl arsonic acid), which contains an arsonic acid moiety structurally similar to inorganic pentavalent arsenate, was conjugated to Sepharose 4B via its para -amino group to form an As(V)–Sepharose matrix. The cellular proteins from KB cells bound to arsonic acid moieties were eluted by 50 m M sodium arsenate in Tris–HCl buffer (50 m M , pH 7.6). A single protein band with a molecular mass of 58 kDa was shown on a sodium dodecyl sulfate–polyacrylamide gel. By immunoblotting, amino acid sequencing and enzymatic analysis, the sodium arsenate-eluted 58-kDa protein was demonstrated to be a human PK (type M2). By using this one-step As(V)–Sepharose chromatography, PK from KB cells was purified 35.4-fold with a specific activity of 153.15 U/mg protein in the presence of 6 m M fructose-1,6-biphosphate. Although PK was eluted from an As(V)–Sepharose column with sodium arsenate, PK activity was apparently inhibited by the used eluent system, but not by p -arsanilic acid, indicating a specific interaction of As(V) to PK. In summary, our results indicate that As(V)–Sepharose can serve as a simple and efficient chromatographic support for PK purification from KB cells.

A light-mixing module consisting of a compound parabolic concentrator (CPC) and a fiber for mixing light from red, green, blue, and white (RGBW) LEDs was proposed. The design principle was investigated and a design prototype was demonstrated in a simulation. The simulated results showed that the chromatic nonuniformity was reduced to 1/10 when the fiber length was 40 times the core width, and the module efficiencies were more than 80% and more than 60% when the fiber lengths were 350 mm and 5 m, respectively. The proposed module is suitable for solar lighting compensation or indoor lighting, such as plant-factory lighting.