A fiber Bragg grating (FBG) was written in a novel "quasi-rectangle" high birefringence by the phase-mask method. Two wavelengths corresponding to fast-axis mode and slow-axis are observed this grating, wavelength splitting as large 0.765 nm obtained. The changes proportionally temperature, but remains same strain increases. This FBG can be used measure temperature simultaneously.

In this paper, a novel hollow-core ring photonic crystal fiber (HR-PCF) is proposed based on As <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> S xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> . It supports the transmission of up to 38 orbital angular momentum (OAM) modes. composed concentric cladding air holes gradually increasing in diameter. addition, center also has large circular hole. A numerical simulation accomplished using...

This article proposes an efficient thermoelectric temperature control system based on improved proportional integral differential (PID) algorithm in which energy feedback technology is used to enhance cooling. In the proposed power management system, two groups of batteries are efficiently and alternatingly charged discharged such that information circuit can be monitored real time. The PID by using idea a state machine coolers (TEC) through H-bridge with pulsewidth modulation. Finally,...

The thermoelectric generator (TEG) is typically used as a clean power supply to harvest waste heat energy in applications involving large thermal gradient, such industrial removal and electronic equipment systems. However, it often difficult achieve the optimal output loop of array system TEG owing different loads. This article proposes an improved fast terminal sliding-mode variable-structure control algorithm (FTSMC) maximize point tracking. function nonlinear surface allows us obtain...

There exists the transient thermoelectric supercooling effect that can be enhanced by keeping on increasing Peltier cooling to compensate for Joule heating and Fourier heat conduction arriving at cold junction, in which a spike produced superimposing an additional shaped current pulse of large magnitude original steady-state optimum value. Most previous work mainly focused minimum temperature achievable separately analyzed beneficial or detrimental effects performance, was not clarified...

A microelectromechanical system (MEMS) mirror based endoscopic swept-source optical coherence tomography (SS-OCT) that can perform three-dimensional (3-D) imaging at high speed is reported. The key component enabling 3-D a two-axis MEMS scanning which has 0.8×0.8 mm 2 plate and 1.6×1.4 device footprint. diameter of the probe only 3.5 mm. rate SS-OCT 50 frames/s . OCT images both human suspicious oral leukoplakia tissue normal buccal mucosa were taken in vivo compared. result agrees well with...

We firstly propose a PCF structure with semicircular air holes. focus on investigating the properties of based silica. It can support 66 OAM modes from wavelength 1.1μm to 1.7μm most modes' confinement losses keeping as low 10-9dB/m. The eigenmodes effective refractive index seperation (Δneff) between HEm+1, 1 mode and EHm-1, are above 10-3. All nonlinear coefficients less than 4w-1/km minimum value is 1.4w-1/km. chromatic dispersion 31.8ps/(nmkm) at 1.55μm. Meanwhile, we also investigate...

Thermoelectric coolers (TECs) are widely used in state-of-the-art thermal management systems. Recently, there is a big trend to power TECs using thermoelectric generators (TEGs). Mainstream research efforts focus on attaining higher figure of merit (ZT) material, which now faces great challenge. Alternatively, this article proposes different approach improve the performance TEC, that is, integration TEG with TEC. The converts collected heat energy into electric current, reduces consumption...

Based on the characteristics of phase change concentrated heat, this article proposes a photovoltaic/phase change/thermoelectric (PV-PCM-TE) self-supply system with sidewall integrated TE. In system, an intelligent control circuit for time is designed to intelligently switch TE working mode using real-time temperature tracking. Therefore, material (PCM) delayed enhanced heat absorption and storage capacity, resulting in greater suppression PV rise. constant difference during change, more...

Abstract Annular thermoelectric generators (ATEGs) have attracted attention in the waste heat recovery field due to their shape similarity automotive exhaust pipes and industrial pipes. To further improve performance of ATEGs, we propose an ATEG with staggered V-shaped fin rings (V-ATEG). An adjustable 3D physical model modifiable pipe length module dimensions is established accommodate various pipeline configurations. Energy conservation equations mutually coupled electric thermal fields...

A two-axis scanning microelectromechanical (MEMS) mirror enables an optical coherence tomography (OCT) system to perform three-dimensional endoscopic imaging due its fast scan speed and small size. However, the radial from MEMS causes various distortions in OCT images, namely spherical, fan-shaped keystone distortions. In this paper, a new method is proposed correct all of three presented systems based on mirrors. The spherical distortion corrected first by directly manipulating original...

In this article, a comprehensive and efficient thermal management system is proposed to harvest reuse the waste of high-power light-emitting diodes (HP-LEDs) for first time. Besides conventional cooling system, including thermoelectric (TE) cooler (TEC), heatsink, fan, also employs TE generator (TEG), temperature sensor, voltage boost converter, microcontroller recycling. some released by HP-LED harvested TEG converted into electrical energy. With help power used sensor monitoring surface...

In this paper, a new double-photonic crystal fibre (D-PCF) is proposed and numerically investigated, result shows that can support angular momentum (OAM) mode transmission up to 26. Based on As2S3 substrate, the D-PCF composed of three well-ordered air-hole rings in cladding another several at centre. Due large effective index difference greater than 10−4 between eigenmodes, OAM be well separated with D-PCF. addition, confinement loss less 7 × 10−9 dB/m for all eigenmodes obtained...

We propose a novel four-ring hollow-core silicon photonic crystal fiber (PCF), and we systematically theoretically investigate the properties of their vector modes. Our PCF can stably support 30 OAM states from wavelength 1.5 μm to 2.4 μm, with large effective refractive index separation above 1×10−4. The confinement loss is less than 1×10−9 dB/m at 1.55 average 1×10−8 1.2 μm. Moreover, curve dispersion tends flatten as increases. In addition, comparably PCFs different hole spacing. This...

Graphene provides a new opportunity for thermoelectric study based on its unique heat transfer behavior controllable by gate voltage. In this paper, an effective thermal conductivity model of graphene cooling is proposed. The double-voltage-control mechanism. According to the law Fourier conduction, proposed device derived taking tunable external voltage into account. Then, used which can change graphene's characteristics. To verify correctness and effectiveness model, circuit simulation...

As an electronically controlled glass whose transmittance varies with voltage, polymer dispersed liquid crystal (PDLC) has the advantages of good privacy, high transmittance, fast response speed, and heat shielding performance. It can be applied to building windows. However, PDLC needs consume extra power, not yet been integrated intelligent home environment control. In this article, we propose adaptive variable voltage step-size control algorithm in field programmable gate array...

A novel method is presented for rapid measurement of optical rotatory dispersion (ORD). Light passes through a polarizer, sample and analyzer, to transmission grating that disperses the collimated light beam. step-motor rotating stage controlled by digital signal processor changes analyzer orientation. The power measured charge-coupled device (CCD) after each rotating-stage step. rotation angle wavelength determined from shift between two Malus curves obtained CCD pixel. ORD spectrum...

Ring-core optical fibre has been successfully demonstrated to have good performance for lifting mode degeneracy, and maintaining orbital angular momentum (OAM) modes in the first radial order, making it promising applications of OAM multiplexing generation cylindrical vector beams. The degeneracy lift can be intensified using a hollow ring-core fibre, i.e. when innermost layer waveguide is air. cut-off ring thickness supporting lowest order are obtained under various refractive index...