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GDM： A New Graph Based Data Model Using Functional Abstractionx

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Journal of Computer Science & Technology 2006年第3期21卷 430-438页

作者： Sankhayan choudhury Nabendu Chaki Swapan Bhattacharya Department of Computer Science and Engineering University of Calcutta India Department of Computer Science and Engineering Jadavpur University India

In this paper, a Graph-based semantic Data Model （GDM） is proposed with the primary objective of bridging the gap between the human perception of an enterprise and the needs of computing infrastructure to organize information in some particular manner for efficient storage and retrieval. The Graph Data Model （GDM） has been proposed as an alternative data model to combine the advantages of the relational model with the positive features of semantic data models. The proposed GDM offers a structural representation for interacting to the designer, making it always easy to comprehend the complex relations amongst basic data items. GDM allows an entire database to be viewed as a Graph （V, E） in a layered organization. Here, a graph is created in a bottom up fashion where V represents the basic instances of data or a functionally abstracted module, called primary semantic group （PSG） and secondary semantic group （SSG）. An edge in the model implies the relationship among the secondary semantic groups. The contents of the lowest layer are the semantically grouped data values in the form of primary semantic groups. The SSGs are nothing but the higher-level abstraction and are created by the method of encapsulation of various PSGs, SSGs and basic data elements. This encapsulation methodology to provide a higher-level abstraction continues generating various secondary semantic groups until the designer thinks that it is sufficient to declare the actual problem domain. GDM, thus, uses standard abstractions available in a semantic data model with a structural representation in terms of a graph. The operations on the data model are formalized in the proposed graph algebra. A Graph Query Language （GQL） is also developed, maintaining similarity with the widely accepted user-friendly SQL. Finally, the paper also presents the methodology to make this GDM compatible with the distributed environment, and a corresponding query processing technique for distributed environment is also sugg

关键词： graph data model semantic group semantic data model distributed database fragmentation and allocation schema

Neoproterozoic highly fractionated Ⅰ-type granitoids of Shillong Plateau, Meghalaya, Northeast India: geochemical constraints on their petrogenesis

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Acta Geochimica 2021年第1期40卷 51-66页

作者： Debjani choudhury M.Faruque Hussain Department of Earth Science Assam UniversitySilchar 788011India

There are several Pan-African granitoid plutons widely distributed in Shillong Plateau,NE ***(506.7±7 Ma)and Mylliem(480-430 Ma)plutons were chosen for the petrological and geochemical study to constrain their *** pluton consists of coarse-grained porphyritic quartz-monzogranite(NQM)and Mylliem pluton consists of medium to coarse-grained porphyritic granite(MG).The constituent minerals are K-feldspar,plagioclase,quartz,and biotite in both granitoids with accessory minerals of hornblende,zircon,sphene,and *** NQM and MG are metaluminous to weakly peraluminous(A/CNK=0.82-1.06),exhibit varied ranges of SiO2(NQM:58.4-64.9 wt%;MG:66.9-69.9 wt%),and display a clear compositional gap in the Harker variation *** contains higher abundances of CaO,MgO and Fe2O3t and similar K2O and total alkali contents compared to *** have distinctive geochemical features typical of highly fractionated I-type granitoids such as higher abundances of K2O,Al2O3,MgO,CaO,Al2O3+CaO>15 wt%and A/CNKtion in HFSE and HREE and highly fractionated REE patterns with moderate Eu anomalies,implying magma generation in a post-collisional extension setting and thinning induced asthenosphere upwelling,accompanied by the partial melting of the overlying enriched lithospheric *** multi-element diagram of both NQM and MG shows pronounced negative anomalies at Ba,Nb,Sr,P,Zr,and ti which implies a major role of crystal fractionation in their *** concentrations of Th,U,and Pb in the granitoid types point to additional involvement of crustal components in their ***,MGs with more pronounced positive spikes at U,Th,and Pb compared to NQM in multi-element diagram suggests the involvement of more felsic crustal *** observed geochemical features of the granitoid types thus suggest that they are genetically unrelated to each other and their parental magmas were modified during magmati

关键词： Ⅰ-type granitoids Shillong plateau Geochemistry Petrogenesis

An Exact l_(1) Exponential Penalty Function Method for Multiobjective Optimization Problems with Exponential-Type Invexity

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Journal of the Operations Research Society of China 2014年第1期2卷 75-91页

作者： Anurag Jayswal Sarita choudhury Department of Applied Mathematics Indian School of MinesDhanbad 826004JharkhandIndia

The purpose of this paper is to devise exact l_(1) exponential penalty function method to solve multiobjective optimization problems with exponentialtype *** conditions governing the equivalence of the(weak)efficient solutions to the vector optimization problem and the(weak)efficient solutions to associated unconstrained exponential penalized multiobjective optimization problem are *** are given to illustrate the obtained results.

关键词： Exact l_(1)exponential penalty method Exponential penalized vector optimization problems (p,r)-invexity

An Analysis of the Proton Structure Function and the Gluon Distributions at Small x

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Communications in Theoretical Physics 2019年第1期71卷 56-66页

作者： Luxmi Machahari D.K.choudhury Department of Physics Gauhati University Physics Academy of North-East

Recently, we reported an analysis of Proton structure function at small x based on Taylor approximated DGLAP equations assuming a plausible relationship between the singlet and the gluon distributions. In this paper, we report a generalised version of the previous work. A corresponding study of the suggested gluon distribution is also *** present generalised version of the model for the structure function results in a wider x range of phenomenological validity than the earlier one. A comparison of both the models of the proton structure function and the gluon distribution is made with exact result as well as with the Froissart saturated models of Block, Durand and Mckay.

关键词： small x DGLAP equations proton structure function gluon distribution

A New Contraction Principle in Menger Spaces

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Acta Mathematica Sinica,English Series 2008年第8期24卷 1379-1386页

作者： Binayak S.choudhury Krishnapada DAS Department of Mathematics Bengal Engineering and Science UniversityShibpurP.O.- B.GardenShibpurHowrah- 711103West BengalINDIA

In the present work we introduce a new type of contraction mapping by using a specific function and obtain certain fixed point results in Menger spaces. The work is in line with the research for generalizing the Banach＇s contraction principle. We extend the notion of altering distance function to Menger Spaces and obtain fixed point results.

关键词： Menger space φ-contraction fixed point

An Improved Singularity Free Self-Similar Model of Proton Structure Function

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Communications in Theoretical Physics 2017年第1期67卷 61-70页

作者： Baishali Saikia D.K.choudhury Department of Physics Gauhati UniversityGuwahati 781 014AssamIndia Physics Academy of North-East Guwahati 781 014AssamIndia

In this paper we make re-analysis of a self-similarity based model of the proton structure function pursued in recent years. The additional assumption is that it should be singularity free in the entire kinematic range of x:0 < x < 1. We also suggest a plausible singularity free form of the model, which has a wider phenomenological range of validity in Q^2 than the earlier ones.

关键词： self-similarity quark gluon

Infrared Spectra of PH3 and NF_(3): An Algebraic Approach

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Chinese Physics Letters 2013年第7期30卷 9-12页

作者： Joydeep choudhury Nirmal Kumar Sarkar Ramendu Bhattacharjee Department of Physics Assam UniversitySilchar-788011India Department of Physics Karimganj CollegeKarimganj-788710India

Molecular spectroscopy is a branch of physics which deals with the interaction of electromagnetic radiation with *** the new theoretical approach,i.e.,Lie algebraic approach,we calculate the infrared spectra of phosphine in the range from 3000 cm^(-1) to 9500 cm^(-1) and nitrogen trifluoride in the range from 900 cm^(-1) to 4500 cm^(-1).The model Hamiltonian constructed seems to describe the P–H and N–F stretching modes accurately with only four numbers of *** present calculation not only predicts the higher overtones but also shows good agreement with the few observed data.

关键词： parameters. Infrared stretching

Muskingum equation based downstream sediment flow simulation models for a river system

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International Journal of Sediment Research 2016年第2期31卷 139-148页

作者： Briti Sundar Sil Parthasarathi choudhury Department of Civil Engineering Tezpur University Department of Civil Engineering NIT Silchar

Applications of sediment transport and water flow characteristics based sediment transport simulation models for a river system are presented in this *** existing water-sediment model and a new sediment-water model are used to formulate the simulation models representing water and sediment movement in a river *** sediment-water model parameters account for water flow characteristics embodying sediment transport properties of a *** models are revised formulations of the multiple water inflows model describing water movement through a river system as given by the Muskingum *** models are applied to a river system in Mississippi River basin to estimate downstream sediment concentration,sediment discharge,and water *** system and the river section parameters are estimated using a revised and the original multiple water inflows models by applying the genetic *** models estimate downstream sediment transport rates on the basis of upstream sediment/water flow rates to a *** performance is evaluated by using standard statistical criteria;downstream water discharge resulting from the original multiple water inflows model using the estimated river system parameters indicate that the revised models satisfactorily describe water movement through a river *** obtained in the study demonstrate the applicability of the sediment transport and water flow characteristics-based simulation models in predicting downstream sediment transport and water flow rates in a river system.

关键词： Multiple rivers Sediment transport Modeling Estimation Muskingum model

A Lower Bound on Longitudinal Structure Function at Small x from a Self-Similarity Based Model of Proton

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Communications in Theoretical Physics 2014年第5期61卷 654-658页

作者： Akbari Jahan D.K.choudhury Department of Physics Gauhati University

Self-similarity based model of proton structure function at small x was reported in the literature sometime back. The phenomenological validity of the model is in the kinematical region 6.2 × 10-7 ≤ x ≤ 10-2 and 0.045 ≤ Q2 ≤ 120 GeV2. We use momentum sum rule to pin down the corresponding self-similarity-based gluon distribution function valid in the same kinematical region. The model is then used to compute bound on the longitudinal structure function FL（X, Q2） for A1tarelli-Martinelli equation in QCD and is compared with the recent HERA data.

关键词： self-similarity small x longitudinal structure function QCD