This paper proposes a hexagonal photonic crystal fiber （H-PCF） structure with high relative sensitivity for liquid sensing; in which both core and cladding are microstructures. Numerical ...investigation is carried out by employing the full vectorial finite element method （FEM）. The analysis has been done in four stages of the proposed structure. The investigation shows that the proposed structure achieves higher relative sensitivity by increasing the diameter of the innermost ring air holes in the cladding. Moreover, placing a single channel instead of using a group of tiny channels increases the relative sensitivity effectively. Investigating the effects of different parameters, the optimized structure shows significantly higher relative sensitivity with a low confinement loss.
•The open-channels SPR-based PCF sensor is offered in a gold-coated plasmonic material.•The proposed PCF-SPR sensor accomplishes the highest WS of 7000 nm/RIU and an AS of 593.61 RIU-1 within RI ...1.39.•The sensor acquires resolution of 1.43 x 10-5 RIU and maximum Y-axis peak loss is 302.78 (dB/cm) with RI from 1.33 to 1.40.
The control of light in photonic crystal fiber (PCF) is a special characteristic that is obtained due to the relations between material and light. In this paper, a surface plasmon resonance (SPR) based PCF sensor is introduced with two open-channel which cover an extensive field of bio-detection applications. Gold (Au) is considered as an effective plasmonic ingredient. The transformation of light through the fiber core is coupled with the gold and stimulates SPR. The proposed PCF-SPR sensor reports the highest wavelength sensitivity (WS) of 7000 nm/RIU (refractive index unit) as well as an amplitude sensitivity (AS) of 593.61 RIU−1. It also acquires an increased sensor resolution of 1.43 × 10−5 RIU and a decent figure of merit (FOM) is 94.97 RIU−1. Additionally, the operating constraints of the sensor such as corresponding air-holes diameter, the pitch, gold layer (Au) thickness and open-channel radius are revised to improve detection performance. The overall measurement is carried out over a broad range of variations in refractive index (RI) from 1.33 to 1.40. The sensor's appreciable performance makes it suitable for bio-sensing applications.
This paper proposes the design and optimization of microstructure optical fiber for liquid sensing applications. A number of propagation characteristics have been compared between two formations of ...hexagonal cladding of our proposed PCF structure. The core of the proposed PCF structure is designed with two rows of supplementary elliptical air holes. We investigate the performance of the designed PCFs for Ethanol as a liquid sample to be sensed. Numerical analysis is carried out by employing the full vectorial Finite Element Method (FEM) to examine the modal birefringence, confinement loss, relative sensitivity and nonlinear coefficient of the proposed PCF structure. Keywords: Liquid sensor, Fiber optics sensor, Photonic crystal fiber, Rotated hexagonal cladding, Nonlinear optics
This paper presents an optimum design for highly sensitive square-cored octagonal photonic crystal fiber (S-OPCF) based liquid sensor. Full vectorial finite element method (FEM) with perfectly ...matched layer (PML) circular boundary has been applied to investigate propagation characteristics of proposed structure, in which both core and cladding are microstructured. Ring numbers, air filling ratios both in core and cladding area and structural shapes in core region are varied to examine sensitivity and confinement loss. According to simulation, five-ring S-OPCF structure is designed and optimized different parameters. The proposed S-OPCF significantly enhances sensitivity and reduces confinement loss for the optimized parameters. Finally the S-OPCF structure improves the sensitivity 1.16, 1.21 and 1.24 times for water, Ethanol and Benzyne analytes respectively compare to prior structure. In addition to this, the proposed structure operates for a wide range of wavelength from 0.6μm to 2.2μm with larger effective area and also suitable for nonlinear applications.
This paper presents a nonlinear Photonic Crystal Fiber (PCF) based sensor to detect liquid analytes. An extensive analysis has been presented at wide range of wavelength (0.6 μm−1.6 μm) in order to ...investigate the impact of some design parameters. The numerical investigation has been done using the full vector Finite Element Method (FEM). The proposed model provides an outstanding nonlinear coefficient value with high birefringence, high sensitivity, and low confinement loss. The designed model can be used in sensing and bio-sensing research and their applications. Keywords: Photonic Crystal Fiber, Nonlinearity, Birefringence, Sensitivity, Confinement loss, Effective Area
Logistics planners often need to estimate length of a path through
n
random points. The problem has connections to geographical surveys, Steiner tree problems, traveling salesman problems, Amazon.com ...and Alibaba.cn drone aircraft multi-package outbound delivery paths, and aircraft sorties. In this effort, we utilize two applied probability tenets in concert to derive a closed form model for the expected distance between
orderly pairs
of randomly distributed delivery locations across some region. Indeed, by themselves each of the two tenets offer little help but when utilized simultaneously they elucidate the problem. Then, this expected distance is multiplied by (
n
− 1) to estimate the total length of the associated
orderly path
(albeit not the
optimal path
) through the
n
points. This total path length estimate, in turn, provides decision makers with a better information for distribution and logistics planning.
Highly sensitive photonic crystal fiber (PCF) sensors based on the spectacle of surface plasmonic resonance (SPR) are analyzed numerically and demonstrated. The finite element method (FEM) technique ...is used to examine detection performance. This study, an SPR-based PCF structure, has been proposed which achieved a maximum amplitude sensitivity of 573.83 RIU
−1
and wavelength sensitivity of 6000 nm/RIU at refractive index (RI) of 1.39. Plasmonic materials such as gold (Au) and titanium dioxide (TiO
2
) have been implied inside the open channels of the PCF as a thin layer. The study explores different types of effects of detecting variation of gold thickness. The work also uses the simple appearance of air holes and pitch variation to achieve the best level detection performance. Moreover, a simplified geometry of SPR-based PCF has been proposed to trim the complexity of the manufacturing process. With an improved sensitivity performance, the benefit of the sensor will also make promising progress towards the detection of unknown biological analyte.
In this article, we demonstrate a unique hexagonal lattice structure of Photonic Crystal Fiber for liquid sensing applications. Relative sensitivity, confinement loss and birefringence of the ...structure have been investigated theoretically. The numerical inquiry has been taken place using the full vectorial Finite Element Method (FEM). We have shown a comparative performance analysis between two lattice structures of the proposed Photonic Crystal Fiber. It is found that the presence of elliptic air holes instead of circular air holes in the core region and the innermost ring of the cladding bring higher birefringence with high sensitivity and low confinement loss. According to the simulated results, at 1.33μm operating wavelength, the birefringence, confinement loss, and relative sensitivity of the suggested PCF are 2.825×10−3, 2.07×10−6dB/m and 43.84% respectively for Ethanol filled core.
Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has induced a sense of panic around the world as the disease is highly contagious and has ...been spreading in full swing during last 5 months causing millions of COVID-19 patients and hundreds of thousands of deaths. Bangladesh, a country of 170 million people, is not an exception regarding COVID-19; it has reported several thousand COVID-19 patients with several hundred of deaths. This observational study has been planned to assess the scope and limitation of management strategy against COVID-19 patients in a medical college hospital of Bangladesh with available drugs in a real-life situation.
All patients in this cohort (
: 33) were positive for SARS-CoV-2 by polymerase chain reaction (PCR) and they attended the hospital with variable presenting symptoms those ranged from cough and fever to respiratory distress and pneumonia. As per the protocol, the patients were regularly evaluated for several parameters of COVID-19-related pathology. Before discharge, they were checked for SARS-CoV-2 for 2 consecutive times. The management strategy included standard of care (SoC) and administration of hydroxychloroquine and azythromycin, available in Bangladesh.
Out of total 33 patients, 1 patient died at day 4 day after admission. Two patients developed severe complications and were referred to tertiary hospital in Dhaka (2 and 3 days after admission), the capital of Bangladesh, where they recovered and were discharged from hospital after being SARS-CoV-2 negative. The rest 30 patients were discharged from the medical college hospital after being negative for SARS-CoV-2 in two subsequent assessments and improvement of their COVID-related symptoms. The average hospital stay of these patients was 14.5 days with a range of 10-24 days.
It seems that most of the COVID-19 patients may be adequately managed by standard of care management with drug support. However, early diagnosis and hospitalization with adequate care may be important variables for better survival. These factors may be properly ensured if the patient burden remains at a palatable level in forthcoming days in Bangladesh.
Bhuyan MAR, Al Mahtab M, Ashab E,
Treatment of COVID-19 Patients at a Medical College Hospital in Bangladesh. Euroasian J Hepato-Gastroenterol 2020;10(1):27-30.
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