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Design and Numerical Analysis of Ultra-High Negative Dispersion, Highly Birefringent Nonlinear Single Mode Core-Tune Photonic Crystal Fiber (CT-PCF) over Communication Bands

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Optics and Photonics Journal 2023年第10期13卷 227-242页

作者： Amit Halder Wahiduzzaman Emon md. Shamim Anower md. riyad tanshen md. Forkan md. Sharif Uddin Shajib Department of Electrical and Electronic Engineering World University of Bangladesh Dhaka Bangladesh Department of Electrical and Electronic Engineering Rajshahi University of Engineering and Technology (RUET) Rajshahi Bangladesh Department of Electrical and Electronic Engineering Ahsanullah University of Science and Technology (AUST) Dhaka Bangladesh

This paper presents the development of a highly efficient CT-PCF (Core-Tune Photonic Crystal Fiber) with substantial birefringence, tailored for applications in high-bit-rate communication and sensing while minimizing signal loss. The design incorporates a modified broadband dispersion compensating structure, optimized for operation across the E, S, C, and L communication bands within a wavelength range spanning 1360 nm to 1625 nm. Notably, the CT-PCF demonstrates a remarkable birefringence of 2.372 × 10-2 at 1550 nm, surpassing traditional PCF structures. Single-mode performance is evaluated using the Higher Order Mode Extinction Ratio (HOMER) method, revealing a peak HOMER value of 104 at 1550 nm. Furthermore, at 1550 nm, the CT-PCF exhibits exceptional nonlinear characteristics, featuring a high nonlinearity of 50.74 W-1⋅Km-1 for y polarization. In comparison to existing designs, the proposed CT-PCF exhibits superior performance metrics and optical characteristics. Additionally, the y polarization dispersion coefficient of the CT-PCF at 1550 nm is measured at -3534 ps/(nm⋅km). Overall, the CT-PCF represents a significant advancement, outperforming established systems in terms of performance metrics and optical properties.

关键词： Negative Dispersion Birefringence Confinement Loss HOMER Method Single-Mode Performance Optical Properties

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Pressure distribution inside oscillating heat pipe charged with aqueous Al_2O_3 nanoparticles,MWCNTs and their hybrid

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Journal of Central South University 2014年第6期21卷 2341-2348页

作者： md.riyad tanshen Sinil Lee Junhyo Kim Donghoon Kang Jungpil Noh HanShik Chung HyoMin Jeong Sunchul Huh Department of Energy and Mechanical Engineering Gyeongsang National UniversityCheondaegukchi-Gil 38TongyeongGyeongnam 650-160Korea Department of Marine Engineering Mokpo National Maritime UniversityHaeyangdaehak-ro 91Mokpo-siJeollanam-do 530-729Korea Department of Naval Architecture and Ocean Engineering Gyeongsang National UniversityInstitute of Marine IndustryCheondaegukchi-Gil 38TongyeongGyeongnam 650-160Korea Department of Energy and Mechanical Engineering Gyeongsang National UniversityInstitute of Marine IndustryCheondaegukchi-Gil 38TongyeongGyeongnam 650-160Korea

Effective thermal performance of oscillating heat pipe(OHP)is driven by inside pressure *** transfer phenomena were reported in terms of pressure and frequency of pressure fluctuation in multi loop OHP charged with aqueous Al2O3 and MWCNTs/Al2O3 *** influences on thermal resistance of aqueous Al2O3,MWCNTs as well as the hybrid of them in OHP having 3 mm in inner diameter were investigated at 60% filling *** results show that thermal characteristics are significantly inter-related with pressure distribution and strongly depend upon the number of pressure fluctuations with *** of pressure depends upon the power input in evaporative section.A little inclusion of MWCNTs into aqueous Al2O3 at 60% filling ratio achieves the highest fluctuation frequency and the lowest thermal resistance at any evaporator power input though different nanofluids cause different thermal performances of OHPs.

关键词： oscillating heat pipe pressure fluctuation thermal resistance nanofluids

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Characterizing pressure fluctuation into single-loop oscillating heat pipe

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Journal of Central South University 2012年第9期19卷 2578-2583页

作者： PARK Yong-ho md.riyad tanshen md.J.Nine CHUNG Han-shik JEONG Hyo-min Department of Mechanical Engineering Koje CollegeJangseungpoKojeGyeongnamKorea Department of Mechanical and Precision Engineering Gyeongsang National University 445 Inpyeong-dongTongyeongGyeongnam650-160Korea Department of Energy and Mechanical Engineering Institute of Marine IndustryGyeongsang National UniversityCheondaegukchi-Gil 38TongyeongGyeongnam650-160Korea

The pressure characteristics inside single loop oscillating heat pipe （OHP） having 4.5 mm inner diameter copper tube with the loop height of 440 mm were addressed. Distilled water was used as working fluid inside the OHP with different filling ratios of 40%, 60% and 80% of total inside volume. Experimental results show that the thermal characteristics are significantly inter-related with pressure fluctuations as well as pressure frequency. And the pressure frequency also depends upon the evaporator temperature that is maintained in the range of 60-96 ℃. Piezoresistive absolute pressure sensor （Model-Kistler 4045A5） was used to take data. The investigation shows that the filling ratio of 60% gives the highest inside pressure magnitude at maximum number of pressure frequency at any of set evaporator temperature and the lowest heat flow resistance is achieved at 60% filling ratio.

关键词： oscillating heat pipe pressure fluctuation heat flow resistance filling ratio

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Automatic Real-Time Medical Mask Detection Using Deep Learning to Fight COVID-19

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Computer Systems Science & Engineering 2022年第9期42卷 1181-1198页

作者： Mohammad Khalid Imam Rahmani Fahmina Taranum Reshma Nikhat md.Rashid Farooqi Mohammed Arshad Khan College of Computing and Informatics Saudi Electronic UniversityRiyadhSaudi Arabia Computer Science and Engineering Department Muffakham Jah College of Engineering and TechnologyOsmania UniversityHyderabadTelanganaIndia Department of Commerce and Business Management Maulana Azad National Urdu UniversityHyderabadTelanganaIndia Department of Accountancy College of Administrative and Financial SciencesSaudi Electronic UniversityRiyadSaudi Arabia

The COVID-19 pandemic is a virus that has disastrous effects onhuman lives globally;still spreading like wildfire causing huge losses to humanityand economies. There is a need to follow few constraints like social distancingnorms, personal hygiene, and masking up to effectively control the virus *** proposal is to detect the face frame and confirm the faces are properly covered with masks. By applying the concepts of Deep learning, the results obtainedfor mask detection are found to be effective. The system is trained using4500 images to accurately judge and justify its accuracy. The aim is to developan algorithm to automatically detect a mask, but the approach does not facilitatethe percentage of improper usage. Accuracy levels are as low as 50% if the maskis improperly covered and an alert is raised for improper placement. It can be usedat traffic places and social gatherings for the prevention of virus transmission. Itworks by first locating the region of interest by creating a frame boundary, thenfacial points are picked up to detect and concentrate on specific features. Thetraining on the input images is performed using different epochs until the artificialface mask detection dataset is created. The system is implemented using TensorFlow with OpenCV and Python using a Jupyter Notebook simulation environment. The training dataset used is collected from a set of diverse open-sourcedatasets with filtered images available at Kaggle Medical Mask Dataset by Mikolaj Witkowski, Kera, and Prajna Bhandary. To simulate MobilNetV2 classifier isused to load and pre-process the image dataset for building a fully connectedhead. The objective is to assess the accuracy of the identification, measuringthe efficiency and effectiveness of algorithms for precision, recall, and F1 score.

关键词： COVID-19 pandemic convolution neural network deep learning face detection facemask detection global health machine learning

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