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551.
Roy Somasis Mitra Anirban Roy Sudipta Setua Sanjit Kumar 《Multimedia Tools and Applications》2019,78(24):34839-34865
Multimedia Tools and Applications - The appearance and structure of blood vessels in retinal fundus image is a fundamental part of diagnosing different issues related with such as diabetes and... 相似文献
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Madhumita Sahoo Aman Kasot Anirban Dhar Amlanjyoti Kar 《Water Resources Management》2018,32(4):1225-1244
Management of groundwater resources needs continuous and efficient monitoring networks. Sparsity of in situ measurements both spatially and temporally creates hindrance in framing groundwater management policies. Remotely sensed data can be a possible alternative. GRACE satellites can trace groundwater changes globally. Moreover, gridded rainfall (RF) and soil moisture (SM) data can shed some light on the hydrologic system. The present study attempts to use GRACE, RF and SM data at a local scale to predict groundwater level. Ground referencing of satellite data were done by using three machine learning techniques- Support Vector Regression (SVR), Random Forest Method (RFM) and Gradient Boosting Mechanism (GBM). The performance of the developed methodology was tested on a part of the Indo-Gangetic basin. The analyses were carried out for nine GRACE pixels to identify relationship between individual well measurements and satellite-derived data. These nine pixels are classified on the basis of presence or absence of hydrological features. Pixels with the presence of perennial streams showed reasonably good results. However, pixels with wells located mostly near the stream gave relatively poorer predictions. These results help in identifying wells which can reasonably represent the regional shallow groundwater dynamics. 相似文献
554.
Rishideo Kumar Atiar Rahaman Molla Anirban Chakrabarti Anal Tarafder 《Journal of the European Ceramic Society》2018,38(6):2639-2648
The preparation of Eu3+-doped novel K2O-La2O3-Al2O3-SiO2 (KLAS)-based glass and transparent KLS (KLaSiO4) glass–ceramic (GC) nanocomposites is reported. Nanostructures of the transparent GCs were analyzed by FE-SEM, H(R)-TEM and SAED techniques. The average size of the crystallites is calculated using XRD data and found to be in the range 13–19?nm which is matched well with the average particle size observed from TEM images in the range 5–18?nm. Photoluminescence spectra of Eu3+ ions exhibit emission transitions of 5D0?→?7Fj (j?=?0 and 1–4) under the excitation at 394?nm. The emission spectra reveals up to 3-fold enhancement of luminescence performance of the KLS GC nanocomposites compared to as-prepared glass. This enhancement is caused due to entering of Eu3+ ions into the KLS crystal sites by replacing the La3+ ions. Such luminescence properties of KLS glass-ceramic nanocomposites could be a promising candidate as laser host for many laser devices. 相似文献
555.
Mondal Sanjoy Mitra Sukanta Mukherjee Anirban Ghosh Saurav Khatua Sunirmal Das Abhishek Das Rajib K. 《Microsystem Technologies》2022,28(12):2641-2657
Microsystem Technologies - Mobile crowd sensing (MCS) is an emerging sensing platform that concedes mobile users to efficiently collect data and share information with the MCS service providers.... 相似文献
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In this research paper, an optimized 2 × 2 MIMO UWB antenna (antenna‐E) with half circled radiators as well as 50 Ω step fed has been introduced. The proposed UWB MIMO antenna has been evolved from recent peer published papers that provide WLAN notch (5.15‐5.85GHz), ultra wide band width (3.1‐10.6 GHz) and again a very good isolation (?20 dB) also maintained. In this paper the evolutions have been derived from antenna‐A to antenna‐E. The Ultra wide band is achieved by using step feed line, cutting a metal strip on a partial ground plane, a rectangular slot underneath the feed line of each radiator in antenna‐E. A high isolation (?20 dB) is obtained by introducing two inverted Г shaped stubs in the ground plane. Both antenna‐D and antenna‐E maintain high isolation (?20 dB). But antenna‐E performs better isolation compared to antenna‐D. The notch at WLAN band (5.15‐5.85GHz) is achieved by etching rectangular C‐shaped slot on the both the radiators. In antenna‐E two radiators are placed horizontally where as in antenna‐D two radiators placed orthogonally. It has been observed that the dimension of final outcome (antenna‐E) is reduced by 33% compared to antenna‐D without compromising the overall performance of the antenna. 相似文献
558.
The aim of this study is to investigate structure and electrical response of mixed di-tri valent cation containing Ce1-xHo0.1SrxO2-δ (x = 0.02–0.1) ionic conductor. The Rietveld analysis of X-ray diffraction profiles confirms the solubility limit of Sr2+ ions into ceria lattice upto x = 0.06 and the co-existence of secondary phase SrCeO3 afterwards. With the increase of Sr2+ ions into ceria, formation of defect cluster increases and concentration of free oxygen vacancies decreases. The composition x = 0.06 shows lowest conductivity due the highest association energy of defect clusters. The dielectric constant plays a crucial role for the formation of defect clusters and conductivities of the compositions. The presence of SrCeO3 and depletion of oxygen vacancies at grain boundary region enhance the grain boundary resistances. The dielectric constant of grain boundary region affects the grain boundary conductivity. 相似文献
559.
Engineering with Computers - Computing the adjoint for a transient non-linear hyperbolic PDE, like the Savage–Hutter equation for modeling dry granular mass flows, is a challenge with often... 相似文献
560.
Koenen JM Jung S Patra A Helfer A Scherf U 《Advanced materials (Deerfield Beach, Fla.)》2012,24(5):681-686
Novel dye-terminated, hyperbranched polytruxenes and polytruxene-block-polythiophene multiblock copolymers have been synthesized in a simple "AB(2) + A" approach. Photoexcitation into the higher energy polytruxene absorption band results in an efficient excitation energy transfer to the peripheral dye or polythiophene blocks. 相似文献