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Visible–light driven photocatalytic degradation of bisphenol-A using ultrasonically synthesized polypyrrole/K-birnessite nanohybrids:Experimental and DFT studies

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Journal of Environmental Sciences 2019年第5期31卷 161-173页

作者： Jannatun Zia Mohamed Ajeer Ufana Riaz Materials Research Laboratory Department of ChemistryJamia Millia Islamia

Although manganese oxides are known for their semiconductor characteristics, the photocatalytic performance of conducting polymer intercalated K-Birnessite(K-Bi) has not been explored till date. With the view to design a visible light driven organic–inorganic hybrid photocatalyst for rapid degradation of Bisphenol A(BPA), the present work reports the ultrasound-assisted green synthesis of K-Bi/polypyrrole(Ppy) nanohybrids. The loading of Ppy in K-Bi was confirmed by thermogravimetric analysis while the formation of organic–inorganic hybrid was confirmed by infrared spectroscopy. K-Bi revealed a band gap of 2.8 e V while for the nanohybrids it was found to be ranging between 2.4 and 1.6 e V. X-ray diffraction studies confirmed partial intercalation of Ppy chains in the inter-layer space of K-Bi. High resolution transmission electron microscopy and scanning electron microscopy studies showed mixed morphology of K-Birnessite/Ppy nanohybrids. Rapid degradation of BPA was observed under visible irradiation in presence of K-Bi/Ppy nanohybrids and almost90% degradation of 20 mg/L BPA solution was achieved within 120 min. The degradation was found to follow pseudo-first order kinetics and the degraded fragments were identified using liquid chromatography-mass spectrometry. Degradation pathway was proposed based on density-functional theory calculations of fukui index predicting the radical easyattacking(f0) and(f-) sites in BPA.

关键词： Photocatalysis Degradation kinetics Manganese oxide Polypyrrole DFT calculations

Ground and Low-Lying Collective States of Rotating Three-Boson System

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Communications in Theoretical Physics 2016年第4期65卷 473-482页

作者： Mohd.Imran M.A.H.Ahsan Department of Physics Jamia Millia Islamia (Central University)

The ground and low-lying collective states of a rotating system of N=3 bosons harmonically confined in quasi-two-dimension and interacting via repulsive finite-range Gaussian potential is studied in weakly to moderately interacting *** N-body Hamiltonian matrix is diagonalized in subspaces of quantized total angular momenta 0 ≤ L ≤ 4N to obtain the ground and low-lying *** numerical results show that breathing modes with N-body eigenenergy spacing of 2hω⊥,known to exist in strictly 2D system with zero-range(δ-function) interaction potential,may as well exist in quasi-2D system with finite-range Gaussian interaction *** gain an insight into the many-body states,the von Neumann entropy is calculated as a measure of quantum correlation and the conditional probability distribution is analyzed for the internal structure of the *** the rapidly rotating regime the ground state in angular momentum subspaces L=(q/2)N(N-1) with q=2,4 is found to exhibit the anticorrelation structure suggesting that it may variationally be described by a Bose–Laughlin like *** further observe that the first breathing mode exhibits features similar to the Bose–Laughlin state in having eigenenergy,von Neumann entropy and internal structure independent of interaction for the three-boson system considered *** the contrary,for eigenstates lying between the Bose–Laughlin like ground state and the first breathing mode,values of eigenenergy,von Neumann entropy and internal structure are found to vary with interaction.

关键词： Bose–Einstein condensation exact diagonalization breathing mode Bose–Laughlin state von Neumann entropy conditional probability distribution

General Formalism for the BRST Symmetry

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Communications in Theoretical Physics 2013年第4期59卷 439-442页

作者： Suhail Ahmad Departmet of Physics Jamia Millia Islamia University

In this paper we will discuss Faddeev-Popov method for gauge theories with a general form of gauge symmetry in an abstract way. We will then develope a general formalism for dealing with the BRST symmetry. This formal... 详细信息

关键词： BRST symmetry Faddeev-Popov method

Evaluating effectiveness of frequency ratio, fuzzy logic and logistic regression models in assessing landslide susceptibility: a case from Rudraprayag district, India

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Journal of Mountain Science 2017年第11期14卷 2150-2167页

作者： Mehebub SAHANA Haroon SAJJAD Department of Geography Faculty of Natural Sciences Jamia Millia Islamia

Rudraprayag in Garhwal Himalayan division is one of the most vulnerable districts to landslides in India. Heavy rainfall, steep slope and developmental activities are important factors for the occurrence of landslides in the district. Therefore, specific assessment of landslide susceptibility and its accuracy at regional level is essential for disaster management and proper land use planning. The article evaluates effectiveness of frequency ratio, fuzzy logic and logistic regression models for assessing landslide susceptibility in Rudraprayag district of Uttarakhand state, India. A landslide inventory map was prepared and verified by field data. Fourteen landslide parameters and generated inventory map were utilized to prepare landslide susceptibility maps through frequency ratio, fuzzy logic and logistic regression models. Landslide susceptibility maps generated through these models were classified into very high, high, medium, low and very low categories using natural breaks classification. Receiver operating characteristics(ROC) curve, spatially agreed area approach and seed cell area index(SCAI) method were used to validate the landslide models. Validation results revealed that fuzzy logic model was found to be more effective in assessing landslide susceptibility in the study area. The landslide susceptibility map generated through fuzzy logic model can be best utilized for landslide disaster management and effective land use planning.

关键词： Landslide susceptibility Frequency ratio Logistic regression Natural breaks classification Remote sensing Geographic information system

Deep image retrieval using artificial neural network interpolation and indexing based on similarity measurement

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CAAI Transactions on Intelligence Technology 2022年第2期7卷 200-218页

作者： Faiyaz Ahmad Department of Computer Engineering Jamia Millia IslamiaNew DelhiIndia

In content-based image retrieval(CBIR),primitive image signatures are critical because they represent the visual *** signatures,which are algorithmically descriptive and accurately recognized visual components,are used to appropriately index and retrieve comparable *** differentiate an image in the category of qualifying contender,feature vectors must have image information's like colour,objects,shape,spatial *** methods such as sketch-based image retrieval by salient contour(SBIR)and greedy learning of deep Boltzmann machine(GDBM)used spatial information to distinguish between image *** requires interest points and also feature analysis emerged image detection ***,a proposed model to overcome this issue and predict the repeating pattern as well as series of pixels that conclude similarity has been *** this study,a technique called CBIR-similarity measure via artificial neural network interpolation(CBIR-SMANN)has been *** collecting datasets,the images are resized then subject to Gaussian filtering in the pre-processing stage,then by permitting them to the Hessian detector,the interesting points are *** on Skewness,mean,kurtosis and standard deviation features were extracted then given to ANN for *** results are stored in a database for *** the testing stage,the query image was inputted that is subjected to pre-processing,and feature extraction was then fed to the similarity measurement ***,ANN helps to get similar images from the ***-SMANN have been implemented in the python tool and then evaluated for its *** show that CBIR-SMANN exhibited a high recall value of 78%with a minimum retrieval time of 980 *** showed the supremacy of the proposed model was comparatively greater than the previous ones.

关键词： Gaussian filtering Hessian detector image retrieval interpolation and similarity measurement repeating pattern

Computational Fluid Dynamics Approach for Predicting Pipeline Response to Various Blast Scenarios: A Numerical Modeling Study

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Computer Modeling in Engineering & Sciences 2024年第9期140卷 2747-2777页

作者： Farman Saifi Mohd Javaid Abid Haleem S.M.Anas Department of Mechanical Engineering Jamia Millia Islamia(A Central University)New Delhi110025India Department of Civil Engineering Jamia Millia Islamia(A Central University)New Delhi110025India

Recent industrial explosions globally have intensified the focus in mechanical engineering on designing infras-tructure systems and networks capable of withstanding blast *** centered on high-profile facilities such as embassies and petrochemical plants,this concern now extends to a wider array of infrastructures and *** and scholars increasingly prioritize structural safety against explosions,particularly to prevent disproportionate collapse and damage to nearby *** has further amplified the reliance on oil and gas pipelines,making them vital for urban life and prime targets for terrorist ***,there is a growing imperative for computational engineering solutions to tackle blast loading on pipelines and mitigate associated risks to avert *** this study,an empty pipe model was successfully validated under contact blast conditions using Abaqus software,a powerful tool in mechanical engineering for simulating blast effects on buried *** a Eulerian-Lagrangian computational fluid dynamics approach,the investigation extended to above-surface and below-surface blasts at standoff distances of 25 and 50 *** descriptions in the numerical model relied on Abaqus’default mechanical *** analysis revealed varying pipe performance,with deformation decreasing as explosion-to-pipe distance *** explosion’s location relative to the pipe surface notably influenced deformation levels,a key finding highlighted in the ***,quantitative findings indicated varying ratios of plastic dissipation energy(PDE)for different blast scenarios compared to the contact blast(P0).Specifically,P1(25 mm subsurface blast)and P2(50 mm subsurface blast)showed approximately 24.07%and 14.77%of P0’s PDE,respectively,while P3(25 mm above-surface blast)and P4(50 mm above-surface blast)exhibited lower PDE values,accounting for about 18.08%and 9.67%of P0’s PDE,***

关键词： Blast loading computational fluid dynamics computer modeling pipe networks response prediction structural safety

Multiple Object Tracking through Background Learning

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Computer Systems Science & Engineering 2023年第1期44卷 191-204页

作者： Deependra Sharma Zainul Abdin Jaffery jamia millia islamia Department of Electrical EngineeringNew-Delhi110025India

This paper discusses about the new approach of multiple object track-ing relative to background *** concept of multiple object tracking through background learning is based upon the theory of relativity,that involves a frame of reference in spatial domain to localize and/or track any *** of multiple object tracking has seen a lot of research,but researchers have considered the background as ***,in object tracking,the back-ground plays a vital role and leads to definite improvement in the overall process of *** the present work an algorithm is proposed for the multiple object tracking through background *** learning framework is based on graph embedding approach for localizing multiple *** graph utilizes the inher-ent capabilities of depth modelling that assist in prior to track occlusion avoidance among multiple *** proposed algorithm has been compared with the recent work available in literature on numerous performance evaluation *** is observed that our proposed algorithm gives better performance.

关键词： Object tracking image processing background learning graph embedding algorithm computer vision

Fuzzy User Access Trust Model for Cloud Access Control

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Computer Systems Science & Engineering 2023年第1期44卷 113-128页

作者： Aakib Jawed Khan Shabana Mehfuz Department of Electrical Engineering Jamia Millia IslamiaNew Delhi110025India

Cloud computing belongs to a set of policies,protocols,technologies through which one can access shared resources such as storage,applications,net-works,and services at relatively low *** the tremendous advantages of cloud computing,one big threat which must be taken care of is data security in the *** are a dozen of threats that we are being exposed to while avail-ing cloud *** identity and access management,insecure inter-faces and Applications interfaces(APIs),hijacking,advanced persistent threats,data threats,and many more are certain security issues with the cloud *** and service providers face a huge challenge to ensure the security and integ-rity of both network and *** overcome these challenges access control mechanisms are *** access control mechanisms fail to monitor the user operations on the cloud platform and are prone to attacks like IP spoofing and other attacks that impact the integrity of the *** ensuring data integrity on cloud platforms,access control mechanisms should go beyond authentication,identification,and ***,in this work,a trust-based access control mechanism is proposed that analyzes the data of the user behavior,network beha-vior,demand behavior,and security behavior for computing trust value before granting user *** method that computes thefinal trust value makes use of the fuzzy logic *** trust value-based policies are defined for the access control mechanism and based on the trust value outcome the access control is granted or denied.

关键词： Cloud architecture fuzzy logic trust-based access mechanism

An approach to Iocational marginal price based zonal congestion management in deregulated electricity market

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Frontiers in Energy 2016年第2期10卷 240-248页

作者： Md SARWAR Anwar Shahzad SIDDIQUI Department of Electrical Engineering Jamia Millia Islamia (A Central University) New Delhi 110025 India

Congestion of transmission line is a vital issue and its management pose a technical challenge in power system deregulation. Congestion occurs in deregulated electricity market when transmission capacity is not sufficient to simultaneously accommodate all constraints of power transmission through a line. Therefore, to manage congestion, a locational marginal price （LMP） based zonal congestion management approach in a deregulated elec- tricity market has been proposed in this paper. As LMP is an economic indicator and its difference between two buses across a transmission line provides the measure of the degree of congestion, therefore, it is efficiently and reliably used in deregulated electricity market for conges- tion management. This paper utilizes the difference of LMP across a transmission line to categorize various congestion zones in the system. After the identification of congestion zones, distributed generation is optimally placed in most congestion sensitive zones using LMP difference in order to manage congestion. The performance of the proposed methodology has been tested on the IEEE 14-bus system and IEEE 57-bus system.

关键词： locational marginal price (LMP) distributed generation pool market deregulated electricity market,congestion management