Fiber Optik Fabry-Perot Akustik Sensörler için Yeni Bir Diyafram Malzemesi Olarak 2D GaSe Benzetimi

Algılanacak akustik/basınç sinyalinin şiddet ve frekans değerine duyarlı uçlar üretmek diyafram tasarımının doğru yapılmasıyla sağlanır. Kullanılan diyafram malzemesinin hem geometrik boyutları hem de yapısal özellikleri (yoğunluk, Young modülü, Poisson oranı gibi) sensör performansını etkileyen unsurlardır. Bu durumdan ötürü literatürde farklı tipte diyafram malzemeleri araştırılmaktadır. Bu çalışmada diyafram tabanlı fiber optik Fabry-Perot (FP) akustik sensörlerde kilit rol oynayan diyafram performansı üzerine hesaplamalar verilmiştir. Hesaplamalarda diyafram olarak grafen benzeri iki boyutlu (2D) Galyum Selenit (GaSe) kullanılmıştır. 2D malzemeler sınıfına ait GaSe malzemesi fiber optik FP akustik sensör uç tasarımında diyafram olarak ilk defa hesaplanmış ve benzetim yoluyla sensör ucunun performansı teorik olarak elde edilmiştir. Teorik hesaplamalar ve benzetimler neticesinde 2D GaSe malzemesi fiber optik FP akustik sensör uç üretiminde diyafram olarak kullanılabileceği öngörülmüştür. Oluşturulan uçların frekans cevapları ve akustik basınca duyarlılığı teorik olarak hesaplanmış ve literatürde kullanılan diğer geleneksel malzemelerden elde edilen sonuçlar ile karşılaştırılarak verilmiştir. Sensör görünürlüğü ve frekansı açısından GaSe malzemesinin kullanım alanına göre alternatifler sunduğu görülmüştür

ULTRA WIDEBAND SMALL SIZE Y-SHAPED MICRO STRIP PATCH ANTENNA DESIGN

With the developing technology in recent years, wireless mobile devices that can performmultiple tasks at the same time are desired by users. But wireless devices; The problem of powerconsumption, dimensions, frequency spectrum constraint, and desire for high performance haveencouraged researchers to develop new technologies. Ultra-Wideband communicationtechnology can be considered as a short-range wireless mobile communication system with lowpower consumption and high data rate. Due to the broadband requirements in the field ofcommunication, broadband antennas have become popular today. Ultra-Wideband increasesthe need for broadband antennas with reduced dimensions in both military and commercialapplications. In this context, microstrip antennas come to the fore with their many remarkablefeatures such as their simple structure, small dimensions, applicability to smooth and inclinedsurfaces, and being durable when applied to hard surfaces.Within the scope of this study, a microstrip patch antenna with a Y-shaped structure operatingbetween 3.78 GHz and 13.56 GHz was designed for ultra-broadband applications. CSTMicrowave Studio program was used in designs. The antenna is designed on the RT Droid 5880base material with 1.57 mm thickness, 2.2 epsilon value, and 0.0009 tangent loss. An annealedcopper conductor with a thickness of 0.02 mm is used for the antenna part and the ground plane.The antenna has a very small and compact structure with dimensions of 20 mm × 21 mm × 1.57mm. In the simulations, the bandwidth, S11, and radiation pattern were examined and it wasevaluated that it could be used in wireless body area network applications due to the small sizeof the antenna.&nbsp; </p

The Temperature Effect on U and Coil Shaped POF Sensors to Detect Refractive Index Change

The effect of the temperature on refractive index (RI) sensors based on U and Coil-shaped plastic optical fiber (POF) was investigated. For this purpose, four POF-RI sensor probes were produced, and RI changes caused by ethanol changes in solutions were detected. Two of the produced probes were U-shaped, while the other two were Coil-shaped. For the first time in the literature, the effect of both the geometry of the U and Coil-shaped POF-RI sensors on the sensor parameters and the effect of the medium temperature have been analyzed together. As a result of the experiments conducted at 25°C, the best RI change detection sensitivity, linearity, and resolution values were determined as 821%/RIU, 0.9974 (R2), 5.18&nbsp;×&nbsp;10−4. In addition, temperature dependence loss (TDL) and temperature dependence RI deviation (TDR) were measured at different temperatures (25–40°C) in the 1.3346–1.45 RI range, and the effect of temperature change on POF-RI sensor probes was characterized.</p