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Insect Science 2015年第4期22卷 569-577页

作者： Pankaj Yadav Deepak choudhury Madhumala K. Sadanandappa Vijay Kumar Sharma Chronobiology Laboratory Evolutionary and Organismal Biology Unit Jawaharlal Nehru Centre for Advanced Scientific Research Bangalore 560064 Kamataka India

Circadian clocks time developmental stages of fruit flies Drosophila melanogaster, while light/dark （LD） cycles delimit emergence of adults, conceding only during the ＂allowed gate.＂ Previous studies have revealed that time-to-emergence can be altered by mutations in the core clock gene period （per）, or by altering the length of LD cycles. Since this evidence came from studies on genetically manipulated flies, or on flies maintained under LD cycles with limited range of periods, inferences that can be drawn are limited. Moreover, the extent of shortening or lengthening of time-to-emergence re- mains yet unknown. In order to pursue this further, we assayed time-to-emergence of D. rnelanogaster under 12 different LD cycles as well as in constant light （LL） and constant dark conditions （DD）. time-to-emergence in flies occurred earlier under LL than in LD cycles and DD. Among the LD cycles, time-to-emergence occurred earlier under T4-T8, followed by T36-T48, and then T12-T32, suggesting that egg-to-emergence duration in flies becomes shorter when the length of LD cycles deviates from 24 h, bearing a strong positive and a marginally negative correlation with day length, for values shorter and longer than 24 h, respectively. These results suggest that the extent of mismatch between the period of circadian clocks and environmental cycles determines the time-to-emergence in Drosophila.

关键词： circadian Drosophila light/dark regimes period time-to-emergence

UNIFORM CONVERGENCE AND SEQUENCE OF MAPS ON A COMPACT METRIC SPACE WITH SOME CHAOtiC PROPERtiES

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Analysis in Theory and Applications 2010年第1期26卷 53-58页

作者： Indranil Bhaumik Binayak S. choudhury Bengal Engineering and Science University India

Recently, C. Tain and G. Chen introduced a new concept of sequence of time invariant function. In this paper we try to investigate the chaotic behavior of the uniform limit function f ： X →X of a sequence of continuous topologically transitive （in strongly successive way） functions fn ： X →X, where X is a compact interval. Surprisingly, we find that the uniform limit function is chaotic in the sense of Devaney. Lastly, we give an example to show that the denseness property of Devaney＇s definition is lost on the limit function.

关键词： uniform convergence chaos in the sense of Devaney topological transitivity in strongly successive way

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

Effect of Cerium Doping on Microstructure and Dielectric Properties of BatiO_3 Ceramics

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Journal of Materials Science & Technology 2011年第8期27卷 759-763页

作者： Sabina Yasmin Shamima choudhury M.A. Hakim A.H. Bhuiyan M.J. Rahman Department of Physics University of Dhaka Materials Science Division Atomic Energy Centre Department of Physics Bangladesh University of Engineering and Technology

A solid state reaction method was used to synthesize barium titanate （BT） and barium cerium titanate （BCT） ceramics at sintering temperature of 1473 K for 4 h. The effect of cerium （Ce） on the structure, microstructure and dielectric properties of BCT was investigated. The scanning electron microscopy （SEM） investigations revealed that the grain size increases with increasing Ce content. The X-ray diffraction （XI^D） patterns showed mostly the BT phase, where the lattice parameter decreased with the addition of Ce. The temperature dependence of dielectric constant showed decrease in the phase transition temperature with higher Ce content. The dielectric constant decreased slightly with increasing frequency. The direct current （dc） density-voltage characteristics of the ceramics showed ohmic behavior for both the BT and BCT. As the temperature increased, the dc resistivity of the ceramics decreased. The activation energy increased with increasing Ce content.

关键词： Cerium doped Ba1-xCextiO3 Dielectric constant Current density

A SIMPLE PROOF OF THE CHAOtiCITY OF SHIFT MAP UNDER A NEW DEFINItiON OF CHAOS

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Analysis in Theory and Applications 2011年第4期27卷 332-339页

作者： Indranil Bhaumik Binayak S.choudhury Basudeb Mukhopadhyay Bengal Engineering and Science University India

Recently, Du has given a new strong definition of chaos by using the shift map. In this paper, we give a proof of the main theorem by constructing a dense uncountable invariant subset of the symbol space E2 containing transitive points in a simpler way with the help of a different metric. We also provide two examples, which support this new definition.

关键词： symbol space shift map δ-scrambled set chaos transitive points

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

Statistical analysis of dynamic fibrils observed from NST/BBSO observations

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Research in Astronomy and Astrophysics 2018年第2期18卷 43-52页

作者： Thambaje Gopalan Priya Jiang-Tao Su Jie Chen Yuan-Yong Deng Debi Prasad choudhury Key Laboratory of Solar Activity National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China University of Chinese Academy of Sciences Beijing 100049 China State Key Laboratory for Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100190 China California State University Northridge CA 91330 USA

We present the results obtained from the analysis of dynamic fibrils in NOAA active region （AR） 12132, using high resolution Ha observations from the New Solar Telescope operating at Big Bear Solar Observatory. The dynamic fibrils are seen to be moving up and down, and most of these dynamic fibrils are periodic and have a jet-like appearance. We found from our observations that the fibrils follow almost perfect parabolic paths in many cases. A statistical analysis on the properties of the parabolic paths showing an analysis on deceleration, maximum velocity, duration and kinetic energy of these fibrils is presented here. We found the average maximum velocity to be around 15 km s-1 and mean deceleration to be around 100 m s-2. The observed deceleration appears to be a fraction of gravity of the Sun and is not compatible with the path of ballistic motion due to gravity of the Sun. We found a positive correlation between deceleration and maximum velocity. This correlation is consistent with simulations done earlier on magnetoacoustic shock waves propagating upward.

关键词： Sun: sunspots-oscillation -- Sun: magnetic fields -- Sun: chromosphere

Aggressive restenosis after percutaneous intervention in two coronary loci in a patient with human immunodeficiency virus infection

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World Journal of Clinical Cases 2017年第2期5卷 40-45页

作者： Mohammad Alkhalil Christopher P Conlon Houman Ashrafian Robin P choudhury Division of Cardiovascular Medicine Radcliffe Department of Medicine University of Oxford John Radcliffe Hospital Department of Infectious Diseases Churchill Hospital Department of Cardiology John Radcliffe Oxford Acute Vascular Imaging Centre (AVIC) Radcliffe Department of Medicine University of OxfordJohn Radcliffe Hospital

A 54-year-old black African woman, 22 years human immunodeficiency virus(HIV)-positive, presented with an acute coronary syndrome. She was taking two nucleoside reverse transcriptase inhibitors and two protease inhibitors. Viral load and CD4 count were stable. Angiography revealed a right coronary artery lesion, which was treated with everolimus eluting stent. She also underwent balloon angioplasty to the first diagonal. She re-presented on three different occasions and technically successful coronary intervention was performed. The patient has reported satisfactory compliance with dual anti platelet therapy throughout. She was successfully treated with surgical revascularisation. The patient did not experience any clinical recurrence on follow up. This case demonstrates exceptionally aggressive multifocal and recurrent instent restenosis in a patient treated for HIV infection, raising the possibility of an association with HIV infection or potentially components of retro viral therapy.

关键词： Coronary artery disease Restenosis Human immunodeficiency virus

Genetic Characterization of Indigenous Rice Varieties in Eastern Himalayan Region of Northeast India

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Rice science 2014年第2期21卷 90-98页

作者： Baharul Islam choudhury Mohammed Latif KHAN Selvadurai DAYANANDAN Forest and Evolutionary Genomics Laboratory and Centre for Structural and Functional GenomicsBiology DepartmentConcordia University Québec Centre for Biodiversity Sciences 1205 Dr.Penfield Avenue MontréalQC Department of Forestry North Eastern Regional Institute of Science & Technology Department of Botany Dr.Harisingh Gour Central University

The eastern Himalayan region of Northeast （NE） India is home to a large number of indigenous rice varieties, which are traditionally classified as Oryza sativa subspecies indica, japonica or intermediate types. The classification based on traditional Cheng’s index is often inconclusive due to phenotypic plasticity of morphological characters, which are influenced by environmental conditions. We used molecular markers specific for indica and japonica subspecies to assess the degree of genetic relatedness of indigenous rice varieties in NE India. The results revealed that majority of upland （jum） and glutinous rice varieties, traditionally considered as japonica, were genetically close to the subspecies indica. All varieties of boro ecotype were found to be indica type, and only a few varieties cultivated in lowland and upland areas were japonica type. Some of the lowland varieties of the sali ecotype were intermediate between indica and japonica, and they showed a closer genetic affinity to O. rufipogon.

关键词： classification genetic characterization insertion and deletion marker indica japonica O. sativa

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