Applied Mechanics and Materials Vols. 84-85

Abstract: The manufacturing engineering of bamboo fiber reinforced friction material was introduced in this paper. ANSYS was used to do adaptive meshing and establish the contact, impose constraints load and solve, then the temperature field of bamboo fiber reinforced friction material was obtained. The results showed that under the coupling effect of friction heat and pressure, Brake blocks and brake discs in the contact area showed local changes in temperature and stress characteristics. The thermal stress of coupled parts contact surface showed a inhomogeneous distribution. Contact pressure distribution and temperature distribution interact each other, the contact pressure distribution of the coupled parts affects the temperature distribution, and the local feature of temperature distribution of the coupled parts conversely affects the contact pressure distribution. It will provide an important theoretical basis for devising friction brake and selecting material of the friction pair.

Abstract: The magnetic hysteresis loops of Nd₂Fe₁₄B/α-Fe/Nd₂Fe₁₄B exchange-coupling trilayer film are simulated by micromagnetic theory, and the relationship between remanence, coercivity, energy products and soft magnetic thickness are discussed in detail. The results show that the hysteresis loops is rectangle and the trilayer films are in complete exchange-coupling region when the soft magnetic thickness is below the critical point(5nm); With the increase of the soft magnetic thickness, the coercivity of the trilayer films decreases monotonically. Maximum energy products are obtained when the soft magnetic thickness is 5nm.

Abstract: Paper has been removed due to double publication.

Abstract: On the basis of brief analysis of the deficiencies of the existing traffic light control system. According to the actual needs of the traffic light, a traffic light control system with remote monitoring by using GPRS wireless module is designed. ForceControl configuration software is used as the monitoring software in the control center. To achieve traffic light control and running test, it exchanges information with each intersection of the field control system through GPRS wireless and communication network. The system realizes wireless remote monitoring of traffic lights, retrenches monitoring cost, improves the system stability and reliability, and facilitates the transformation of the system and the increase of traffic intersections.

Abstract: In this paper, measurement method for the refractive index of chemical substances based on fiber Bragg grating (FBG) sensor was proposed. The relation between Bragg wavelength shift and surrounding refractive index (SRI) was analyzed theoretically and experimentally. The SRI sensitivity of the chemical sensor could be enhanced by reducing the cladding thickness of the FBG using hydrofluoric acid (HF) solution etching process. The experimental results indicated that the variation of Bragg wavelength increased as the SRI increased. In the low SRI region, the relationship between the Bragg wavelength shift and the change of the SRI was approximately linear.

Abstract: The low refractive index sensing principle of the fiber Bragg grating (FBG) was analyzed theoretically, the temperature compensation scheme corresponding to the theoretical model was established. A single-end etched FBG was designed and fabricated for simultaneous measurement of temperature and refractive index. The experimental results demonstrated that the Bragg wavelength shift exhibits a nonlinear behavior with the temperature and yeast refractive index changes. The temperature change to the influence of the sensor was eliminated by numerical analysis, and then the relationship between the Bragg wavelength shift and the yeast refractive index is linear, the sensor yeast refractive index sensitivity of 5.42nm/riu was obtained.

Abstract: According to the principle of carrier diffusion, aluminum nitride (AlN) coating, and RIE deep etching technology are implemented, 1064 nm broad area distribution electrode lasers have been obtained exhibiting near single lobe near and far field. We report electrode pattern lasers emitting at 1064 nm with the minimal full width at half maximum (FWHM) horizontal angle of 2.7° while the maximum continuous-wave output power up to 3.65 W and slope efficiencies as high as 0.85 W/A.

Abstract: High-performance 785 nm wavelength super-luminescent diodes (SLDs) with ring cavity were fabricated. The maximum output power of 100 mW was obtained in continuous wave (CW) mode under room temperature. The full width at half maximum (FWHM) of the emission spectrum was 24 nm.

Abstract: Integrated 808 nm wavelength super-luminescent diodes (SLDs) with a ring seed source and a tapered amplifier were fabricated tilted at 8° from the facet normal. Max-output power of 700 mW was obtained in continuous wave (CW) mode under room temperature, and the full width at half maximum (FWHM) of the emission spectrum is 36 nm.

Abstract: We implement the concept of the distributed electrode, which allows to improve the modal behavior of lasers and to reduce spatial-hole burning effects by preferentially localizing current injection in the center of the structure, hence discriminating the optical mode. We report the first realization of distributed electrode lasers emitting at 808 nm with the measured full width at half maximum (FWHM) angle of the minimal horizontal angle as 3.8° while the maximum continuous-wave output power is up to 4 W and high slope efficiencies as high as 0.95 W/A.