Background: Schools provide a big opportunity for promoting the student's health, life skill, and behavior. Teachers play a fundamental role in the promotion and successful implementation of school health services. This study aimed to assess the level of involvement in the Health Promoting School program and its associated factors and to explore the benefits and barriers to involvement among high school teachers in Myanmar.
View Article and Find Full Text PDFWe report a highly sensitive twist sensor based on a Sagnac interferometer constructed with a new type of optical fiber which contains an elliptical core and two large semicircular-holes, where the slow axis of the core orthogonal to the air-holes has a large sensitivity towards twist-induced birefringent changes. The novel fiber structure results in a highest twist sensitivity of 5.01 nm/° at a chosen dip over the range from 370°-400°.
View Article and Find Full Text PDFA simple, compact, and highly sensitive gas pressure sensor based on a Fabry-Perot interferometer (FPI) with a silicone rubber (SR) diaphragm is demonstrated. The SR diaphragm is fabricated on the tip of a silica tube using capillary action followed by spin coating. This process ensures uniformity of its inner surface along with reproducibility.
View Article and Find Full Text PDFIn this paper, we present a novel accelerometer based on the Sagnac interferometer configuration using a polarization-maintaining photonic crystal fiber (PM-PCF), which has a sensitivity of ~8 pm/G, and a resonant frequency exceeding 2.5 kHz. The proposed accelerometer is capable of functioning with a constant sensitivity in a large frequency range from 0 to 1 kHz which is much wider than many FBG-based accelerometers.
View Article and Find Full Text PDFWe present a novel optical fiber composed of a suspended core, a supporting ring and an outer ring. To establish a large holey region, a germanium-doped core is suspended by a silica ring and the entire structure is enclosed by another silica ring. By monitoring the Bragg wavelength shift of an FBG written in such a fiber with an air filling fraction of 65%, a hydrostatic pressure sensitivity of -43.
View Article and Find Full Text PDFThis paper presents a sensitive and large dynamic range pressure sensor based on a novel birefringence microstructured optical fiber (MOF) deployed in a Sagnac interferometer configuration. The MOF has two large semicircle holes in the cladding and a rectangular strut with germanium-doped core in the center. The fiber structure permits surrounding pressure to induce large effective index difference between the two polarized modes.
View Article and Find Full Text PDFIn this paper, we present a miniature fluidic flow sensor based on a short fiber Bragg grating inscribed in a single mode fiber and heated by Co-doped multimode fibers. The proposed flow sensor was employed to measure the flow rates of oil and water, showing good sensitivity of 0.339 nm/(m/s) and 0.
View Article and Find Full Text PDFWe have developed a cost-effective, high-capacity Er-doped fiber amplifier based on the high-power white LED and a large-core Er-doped fiber. Er ions of the fiber with absorption bands at 453, 488, 523, and 654 nm were simultaneously excited by LED pumping and amplification with optical gain over 12 dB at 1550 nm was obtained.
View Article and Find Full Text PDFWe present a simple and reliable method based on the spectral splice loss measurement to determine the cutoff wavelength of bend insensitive fiber.
View Article and Find Full Text PDF