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Nano-Micro Letters 2017年第2期9卷 58-67页

作者： prasenjit Kar Tuhin Kumar Maji Ramesh Nandi Peter Lemmens Samir Kumar Pal Department of Chemical Biological and Macromolecular Sciences S.N.Bose National Centre for Basic SciencesBlock JDSector ⅢSaltLakeKolkata 700106India Institute for Condensed Matter Physics TU BraunschweigMendelssohnstraße 338106 BrunswickGermany Laboratory for Emerging Nanometrology TU BraunschweigBrunswickGermany

Bismuth containing nanomaterials recently received increasing attention with respect to environmental applications because of their low cost, high stability and nontoxicity. In this work, Bi–Bi_2O_2CO_3 heterojunctions were fabricated by in-situ decoration of Bi nanoparticles on Bi_2O_2CO_3 nanosheets via a simple hydrothermal synthesis approach. X-ray diffraction(XRD), scanning electron microscopy(SEM), transmission electron microscopy(TEM) and high-resolution TEM(HRTEM) were used to confirm the morphology of the nanosheet-like heterostructure of the Bi–Bi_2O_2CO_3 composite. Detailed ultrafast electronic spectroscopy reveals that the in-situ decoration of Bi nanoparticles on Bi_2O_2CO_3 nanosheets exhibit a dramatically enhanced electron-hole pair separation rate, which results in an extraordinarily high photocatalytic activity for the degradation of a model organic dye, methylene blue(MB) under visible light illumination. Cycling experiments revealed a good photochemical stability of the Bi–Bi_2O_2CO_3 heterojunction under repeated irradiation. Photocurrent measurements further indicated that the heterojunction incredibly enhanced the charge generation and suppressed the charge recombination of photogenerated electron-hole pairs.

关键词： Bi nanoparticles Bi–Bi2O2CO3 nanosheets Heterojunction Hydrothermal method Charge separation Visible light photocatalytic activity

Biodiversity effects and transgressive overyielding

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Journal of Plant Ecology 2008年第2期1卷 95-102页

作者： Bernhard Schmid Andy Hector prasenjit Saha Michel Loreau Institute of Environmental Sciences University of ZurichWinterthurerstrasse 190CH-8057 ZurichSwitzerland Physics Institute University of ZurichWinterthurerstrasse 190CH-8057 ZurichSwitzerland Department of Biology McGill University1205 ave Docteur PenfieldMontrealQuebecCanada H3A 1B1

Aims The potential for mixtures of plant species to produce more biomass than every one of their constituent species in monoculture is still controversially discussed in the *** we tested how this socalled transgressive overyielding is affected by variation between and within species in monoculture yields in biodiversity *** We use basic statistical principles to calculate expected maximum monoculture yield in a species pool used for a biodiversity *** a real example we show how between-and withinspecies variance components in monoculture yields can be *** the two components we estimate the importance of sampling bias in transgressive overyielding *** Findings The net biodiversity effect(difference between mixture and average monoculture yield)needed to achieve transgressive overyielding increases with the number of species in a mixture and with the variation between constituent species in monoculture *** there is no significant variation between species,transgressive overyielding should not be calculated using the best monoculture,because in this case the difference between this species and the other species could exclusively reflect a sampling *** sampling bias decreases with increasing variation between *** for transgressive overyielding require replicated species’***,it can be doubted whether such an emphasis on monocultures in biodiversity experiments is justified if an analysis of transgressive overyielding is not the major goal.

关键词： biodiversity experiments mixtures monocultures overyielding analysis sampling bias

Predicting Resource Availability in Local Mobile Crowd Computing Using Convolutional GRU

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Computers, Materials & Continua 2022年第3期70卷 5199-5212页

作者： Pijush Kanti Dutta Pramanik Nilanjan Sinhababu Anand Nayyar Mehedi Masud prasenjit Choudhury Department of Computer Science&Engineering National Institute of TechnologyDurgapurIndia Reliability Engineering Centre Indian Institute of Technology KharagpurIndia Graduate School Duy Tan UniversityDa Nang550000Vietnam Faculty of Information Technology Duy Tan UniversityDa Nang550000Vietnam Department of Computer Science College of Computers and Information TechnologyTaif UniversityTaif21944Saudi Arabia

In mobile crowd computing(MCC),people’s smart mobile devices(SMDs)are utilized as computing *** the ever-growing computing capabilities of today’s SMDs,a collection of them can offer significantly high-performance computing *** a localMCC,the SMDs are typically connected to a local Wi-Fi *** and institutions can leverage the SMDs available within the campus to form local MCCs to cater to their computing needs without any financial and operational *** it offers an economical and sustainable computing solution,users’mobility poses a serious issue in the QoS of *** address this,before submitting a job to an SMD,we suggest estimating that particular SMD’s availability in the network until the job is *** this,we propose a convolutional GRU-based prediction model to assess how long an SMD is likely to be available in the network from any given point of *** experimental purposes,we collected real users’mobility data(in-time and outtime)with respect to a Wi-Fi access *** build the prediction model,we presented a novel feature extraction method to be applied to the time-series *** experimental results prove that the proposed convolutional GRU model outperforms the conventional GRU model.

关键词： Resource selection resource availability mobile grid mobile cloud ad-hoc cloud crowd computing deep learning GRU CNN RNN

A Novel Feature Aggregation Approach for Image Retrieval Using Local and Global Features

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Computer Modeling in Engineering & Sciences 2022年第4期131卷 239-262页

作者： Yuhua Li Zhiqiang He Junxia Ma Zhifeng Zhang Wangwei Zhang prasenjit Chatterjee Dragan Pamucar Software Engineering College Zhengzhou University of Light IndustryZhengzhou450001China China Mobile Group Henan Company Limited Xinxiang453000China Department of Mechanical Engineering MCKV Institute of EngineeringHowrah711204India Department of Logistics University of Defence in BelgradeBelgrade11000Serbia

The current deep convolution features based on retrievalmethods cannot fully use the characteristics of the salient image ***,they cannot effectively suppress the background noises,so it is a challenging task to retrieve objects in cluttered *** solve the problem,we propose a new image retrieval method that employs a novel feature aggregation approach with an attention mechanism and utilizes a combination of local and global *** method first extracts global and local features of the input image and then selects keypoints from local features by using the attention *** that,the feature aggregation mechanism aggregates the keypoints to a compact vector representation according to the scores evaluated by the attention *** core of the aggregation mechanism is to allow features with high scores to participate in residual operations of all cluster ***,we get the improved image representation by fusing aggregated feature descriptor and global feature of the input *** effectively evaluate the proposedmethod,we have carried out a series of experiments on large-scale image datasets and compared them with other state-of-the-art *** show that this method greatly improves the precision of image retrieval and computational efficiency.

关键词： Attention mechanism image retrieval descriptor aggregation convolutional neural network

Prevalence of Argulus sp. in Indian Major Carps from Bhangore Block of South 24 Parganas District, West Bengal, India

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Journal of Fisheries Science 2020年第1期2卷 5-8页

作者： Ratul Chakraborty Debapriyo mukherjee Avishek Bardhan prasenjit Mali Koel Bhattacharya Sanyal Gadadhar Dash Department of Aquatic Animal Health Faculty of Fishery SciencesWest Bengal University of Animal and Fishery Sciences(WBUAFS)5-Budherhat RoadChakgaria CampusP.O.PanchasayarKolkata-700094West BengalIndia

The study was carried out to find the prevalence and severity of Argulus *** Indian Major Carps(IMCs)collected from Bhangore block of South 24 Parganas district of West Bengal during November 2018 to August ***(2019)recorded the highest parasitic prevalence(PFI,83.33%)and the month of August(2019)recorded the lowest parasitic prevalence(PFI,9%).The identities of selected parasites were further confirmed by molecular identification through 18S rDNA *** study revealed that Argulus *** had great economic implications especially in the winter months and is one of the most prevalent problems in fresh water aquaculture systems.

关键词： Argulus Bhangore Indian major carps Parasites Prevalence Severity

Using DEMATEL for Contextual Learner Modeling in Personalized and Ubiquitous Learning

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Computers, Materials & Continua 2021年第12期69卷 3981-4001页

作者： Saurabh Pal Pijush Kanti Dutta Pramanik Musleh Alsulami Anand Nayyar Mohammad Zarour prasenjit Choudhury Department of Computer Science and Engineering National Institute of TechnologyDurgapurIndia Department of Information Systems Umm Al-Qura UniversityMakkahKSA Graduate School Duy Tan UniversityDa NangVietnam Prince Sultan University RiyadhSaudi Arabia

With the popularity of e-learning,personalization and ubiquity have become important aspects of online *** make learning more personalized and ubiquitous,we propose a learner model for a query-based personalized learning recommendation *** contextual attributes characterize a learner,but considering all of them is costly for a ubiquitous learning *** this paper,a set of optimal intrinsic and extrinsic contexts of a learner are identified for learner modeling.A total of 208 students are ***(Decision Making Trial and Evaluation Laboratory)technique is used to establish the validity and importance of the identified contexts and find the interdependency among *** acquiring methods of these contexts are also *** the basis of these contexts,the learner model is designed.A layered architecture is presented for interfacing the learner model with a query-based personalized learning recommendation *** a ubiquitous learning scenario,the necessary adaptive decisions are identified to make a personalized recommendation to a learner.

关键词： Personalized e-learning DEMATEL learner model ontology learner context personalized recommendation adaptive decisions

Generating A New Shilling Attack for Recommendation Systems

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Computers, Materials & Continua 2022年第5期71卷 2827-2846页

作者： Pradeep Kumar Singh Pijush Kanti Dutta Pramanik Madhumita Sardar Anand Nayyar Mehedi Masud prasenjit Choudhury Department of Computer Science&Engineering National Institute of TechnologyDurgapurIndia Graduate School Duy Tan UniversityDa NangVietnam Faculty of Information Technology Duy Tan UniversityDa NangVietnam Department of Computer Science College of Computers and Information TechnologyTaif UniversityTaif21944Saudi Arabia

A collaborative filtering-based recommendation system has been an integral part of e-commerce and *** keep the recommendation systems reliable,authentic,and superior,the security of these systems is very *** the existing shilling attack detection methods in collaborative filtering are able to detect the standard attacks,in this paper,we prove that they fail to detect a new or unknown *** develop a new attack model,named Obscure attack,with unknown features and observed that it has been successful in biasing the overall top-N list of the target users as *** Obscure attack is able to push target items to the top-N list as well as remove the actual rated items from the *** proposed attack is more effective at a smaller number of k in top-k similar user as compared to other existing *** effectivity of the proposed attack model is tested on the MovieLens dataset,where various classifiers like SVM,J48,random forest,and naïve Bayes are utilized.

关键词： Shilling attack recommendation system collaborative filtering top-N recommendation biasing shuffling hit ratio

Coal-derived humic acid for application in acid mine drainage(AMD)water treatment and electrochemical devices

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International Journal of Coal Science & Technology 2021年第6期8卷 1479-1490页

作者： Tonkeswar Das Mousumi Bora Joyshil Tamuly Santhi Maria Benoy Bimala PBaruah prasenjit Saikia Binoy K.Saikia Coal and Energy Group Materials Science and Technology DivisionCSIR-North East Institute of Science and TechnologyJorhat 785006India Academy of Scientific and Innovative Research(AcSIR) Ghaziabad 201002India

In this research work,isolation of humic acid from coal of Northeastern region of India is *** study is also targeted for application of the coal-derived humic acid in acid mine drainage(AMD)water treatment and electrochemical *** the obtained results are compared with the standard humic acid and examined the formation of humic acid from the *** isolated coal-derived humic acid is found to be high degree of humifications and relatively stable up to about 200℃.The FTIR study indicates the formation of metal-humic acid *** treatment with acidic water(AMD),the coal-derived humic acid was found to have the ability to remove toxic metal such as(in order)Pb>Cu>Zn>*** addition,the preliminary electrochemical properties of the isolated humic acid are also discussed in the *** specific capacitance of the isolated coal-derived humic acid via cyclic voltammetry and charge-discharge analysis is found to be 7 mF/g at scan rate 10 mV/s and 22 mF/g within the potential window 0.4 V,*** charge-discharge cycles are stable for more than 1000 cycles within the potential window 0.4 *** study will create a new pathway for the further research in this field.

关键词： Value addition of coal Indian coal Humic acid AMD water treatment Electrochemical devices

Chronic hepatitis E–an emerging disease in an immunocompromised host

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Gastroenterology Report 2018年第2期6卷 152-155,I0003页

作者： Amitabh Singh Rachna Seth Anand Gupta Shalimar Baibaswata Nayak Subrat kumar Acharya prasenjit Das Department of Paediatrics All India Institute of Medical SciencesNew DelhiIndia Department of Gastroenterology All India Institute of Medical SciencesNew DelhiIndia Department of Pathology All India Institute of Medical SciencesNew DelhiIndia

Chronic hepatitis E virus(HEV)infection is increasingly being reported in immunosuppressed individuals with HIV,patients with haematological malignancy and transplant *** diagnosis of cirrhosis and liver failure post chronic HEV is controversial due to lack of standard diagnostic *** treatment benefits of ribavirin in chronic HEV of genotype 1 are not well *** report a case of chronic HEV infection of genotype 1 leading to chronic liver disease in a child cured of acute *** report also highlights the successful use of ribavirin for eradicating chronic HEV infection and its subsequent survival *** hepatitis E may be an emerging disease of immunosuppressed patients and should be suspected in the presence of cryptogenic *** is an effective therapy for controlling HEV.

关键词： chronic hepatitis E immunosuppression chronic liver disease ribavirin

Differentiating Crohn's disease from intestinal tuberculosis

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World Journal of Gastroenterology 2019年第4期25卷 418-432页

作者： Saurabh Kedia prasenjit Das Kumble Seetharama Madhusudhan Siddhartha Dattagupta Raju Sharma Peush Sahni Govind Makharia Vineet Ahuja Department of Gastroenterology All India Institute of Medical Sciences Department of Pathology All India Institute of Medical Sciences Department of Radiology All India Institute of Medical Sciences Department of GI Surgery All India Institute of Medical Sciences

Differentiating Crohn's disease(CD) and intestinal tuberculosis(ITB) has remained a dilemma for most of the clinicians in the developing world, which are endemic for ITB, and where the disease burden of inflammatory bowel disease is on the rise. Although, there are certain clinical(diarrhea/hematochezia/perianal disease common in CD; fever/night sweats common in ITB), endoscopic(longitudinal/aphthous ulcers common in CD; transverse ulcers/patulous ileocaecal valve common in ITB), histologic(caseating/confluent/large granuloma common in ITB; microgranuloma common in CD), microbiologic(positive stain/culture for acid fast-bacillus in ITB), radiologic(long segment involvement/comb sign/skip lesions common in CD; necrotic lymph node/contiguous ileocaecal involvement common in ITB), and serologic differences between CD and ITB, the only exclusive features are caseation necrosis on biopsy, positive smear for acid-fast bacillus(AFB) and/or AFB culture, and necrotic lymph node on cross-sectional imaging in ITB. However,these exclusive features are limited by poor sensitivity, and this has led to the development of multiple multi-parametric predictive models. These models are also limited by complex formulae, small sample size and lack of validation across other populations. Several new parameters have come up including the latest Bayesian meta-analysis, enumeration of peripheral blood T-regulatory cells, and updated computed tomography based predictive score. However, therapeutic anti-tubercular therapy(ATT) trial, and subsequent clinical and endoscopic response to ATT is still required in a significant proportion of patients to establish the diagnosis. Therapeutic ATT trial is associated with a delay in the diagnosis of CD, and there is a need for better modalities for improved differentiation and reduction in the need for ATT trial.

关键词： Crohn's disease Intestinal tuberculosis Endoscopy Computed tomographic enterography Granuloma