Jadavpur University

About: Jadavpur University is a education organization based out in Kolkata, India. It is known for research contribution in the topics: Population & Schiff base. The organization has 10856 authors who have published 27678 publications receiving 422069 citations. The organization is also known as: JU & Jadabpur University.

Understanding Deep Learning Techniques for Image Segmentation

Abstract: The machine learning community has been overwhelmed by a plethora of deep learning--based approaches. Many challenging computer vision tasks, such as detection, localization, recognition, and segmentation of objects in an unconstrained environment, are being efficiently addressed by various types of deep neural networks, such as convolutional neural networks, recurrent networks, adversarial networks, and autoencoders. Although there have been plenty of analytical studies regarding the object detection or recognition domain, many new deep learning techniques have surfaced with respect to image segmentation techniques. This article approaches these various deep learning techniques of image segmentation from an analytical perspective. The main goal of this work is to provide an intuitive understanding of the major techniques that have made a significant contribution to the image segmentation domain. Starting from some of the traditional image segmentation approaches, the article progresses by describing the effect that deep learning has had on the image segmentation domain. Thereafter, most of the major segmentation algorithms have been logically categorized with paragraphs dedicated to their unique contribution. With an ample amount of intuitive explanations, the reader is expected to have an improved ability to visualize the internal dynamics of these processes.

ZnO–SnO2 based composite type gas sensor for selective hydrogen sensing

Abstract: This work reports the synthesis and detailed investigation on ZnO–SnO 2 composite type hydrogen sensor prototype. The sensor material was structurally and morphologically characterized by X-ray diffraction technique and scanning electron microscopy, respectively. The gas sensing behaviour of the fabricated sensor prototype was investigated for varied concentration of test gases at different temperature. The cross-response of this sensor to other gases, viz. methane and carbon mono-oxide was also investigated, which showed good selectivity, excellent response and reproducibility to hydrogen at 150 °C.

Luminescent S-doped carbon dots: an emergent architecture for multimodal applications

Abstract: A facile route has been developed to synthesise and isolate sulphur doped fluorescent carbon dots for the first time. Such carbogenic quantum dots exhibit a wide band gap of 4.43 eV with a high open circuit voltage (VOC) of 617 mV along with a fill factor (FF) as high as 37%, using phenyl-C60-butyric acid methyl ester (PCBM) as the electron transporting layer. Besides the wide band gap, which is useful in the fabrication of solar cells, sulphur modified carbon dots also exhibit a high fluorescence quantum yield of 11.8% without any additional surface passivation, producing a unique fluorescent probe for further applications. In addition, the particles have a strong tendency to interact with the surface of gold nanoparticles and produce a thin fluorescent layer over their surfaces. Moreover, as they are completely biocompatible in nature, the highly fluorescent S-doped carbon dots have a strong potential for use in bioimaging applications. Interestingly, owing to the presence of oxygen and sulphur functionality, the highly negatively charged particles can easily bind with positively charged DNA–PEI complexes, simply by mixing them, and after interaction with DNA, bright blue fluorescence has been observed under an excitation wavelength of 405 nm .

An EOQ Model for Deteriorating Items with Linear Time-dependent Demand Rate and Shortages Under Inflation and Time Discounting

Abstract: An economic order quantity (EOQ) inventory model for deteriorating goods is developed with a linear, positive trend in demand allowing inventory shortages and backlogging. The effects of inflation and the time-value of money are incorporated into the model, considering two separate inflation rates: namely, the internal (company) inflation rate and the external (general economy) inflation rate. It is assumed that the goods in the inventory deteriorate over time at a constant rate θ. The inventory policy is discussed over a finite time-horizon with several reorder points. The results are discussed with a numerical example and a sensitivity analysis of the optimal solution with respect to the parameters of the system is carried out. Several particular cases of the model are discussed in brief.

Determination of Dielectric Constant of Fabric Materials and Their Use as Substrates for Design and Development of Antennas for Wearable Applications

Abstract: A novel approach to measure the dielectric constant of fabric substrate materials used for the development of wearable antennas (also called textile antennas) is presented in this paper. The technique reported here is based on the resonance method and focused on the use of microstrip patch radiator, which contains fabric material as its substrate. The accurate value of the dielectric constant of the fabric material can easily be extracted from the measured resonant frequency of the patch radiator. The dielectric constant values of six fabric materials, including jeans cotton, polyester combined cotton, and polyester, have been determined by this way. As an extended objective of this paper, initial investigations are done to study the performance/behavioral characteristics of wearable antennas in the Bluetooth industrial, scientific, and medical band. Two of the six textile antenna structures, developed to meet out the primary objective of determining the dielectric constant of fabrics, are tested, and their performance characteristics, such as impedance bandwidth, gain, efficiency, etc., are measured. In addition, another Bluetooth antenna employing polyester fabric substrate is designed considering its measured accurate value of dielectric constant and subjected to radiation pattern measurements. In general, all the measured antennas yield very good results, fulfilling the requirements for practical applications, and in particular, the third fabric antenna utilizing the accurate value of the dielectric constant determined shows superior performance characteristics compared to others, indicating the correctness of our approach. Thus, the suitability of fabric substrate materials for the development of textile antennas with microstrip patch configuration is also well demonstrated.