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Using the Hg_xMg_(1-x)Te ternary compound as a room temperature photodetector: The electronic structure, charge transport, and response function of the energetic electromagnetic radiation

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Chinese Physics B 2018年第5期27卷 143-149页

作者： Ghasemi hasan Mokhtari Ali Department of Physics Faculty of SciencesShahrekord University

In the present work, firstly, a first-principles study of the structural, electronic, and electron transport properties of the HgxMg1-xTe（HMT） ternary compound is performed using the ABINIT package and the results are compared with Cd0.9Zn0.1 Te（CZT） as a current room-temperature photodetector. Next, the response functions of Hg0.6Mg0.4Te and Cd0.9Zn0.1Te under electromagnetic irradiation with 0.05 Me V, 0.2 MeV, 0.661 MeV and 1.33 MeV energies are simulated by using the MCNP code. According to these simulations, the Hg0.6Mg0.4Te ternary compound is suggested as a good semiconductor photodetector for use at room temperature.

关键词： band gap charge-carrier transport photodetector density functional theory

Cooperative Sensor Anomaly Detection Using Global Information

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Tsinghua Science and Technology 2013年第3期18卷 209-219页

作者： Rui Zhang Ping Ji Dinkar Mylaraswamy Mani Srivastava sadaf Zahedi Intel-GE CareInnovations CAUS the Computer Science Department City University of New YorkNYUS Honeywell Aerospace Advanced Technology MNUS University of California Los AngelesCAUS

Sensor networks are deployed in many application areas nowadays ranging from environment monitoring, industrial monitoring, and agriculture monitoring to military battlefield sensing. The accuracy of sensor readings is without a doubt one of the most important measures to evaluate the quality of a sensor and its network. Therefore, this work is motivated to propose approaches that can detect and repair erroneous （i.e., dirty） data caused by inevitable system problems involving various hardware and software components of sensor networks. As information about a single event of interest in a sensor network is usually reflected in multiple measurement points, the inconsistency among multiple sensor measurements serves as an indicator for data quality problem. The focus of this paper is thus to study methods that can effectively detect and identify erroneous data among inconsistent observations based on the inherent structure of various sensor measurement series from a group of sensors. Particularly, we present three models to characterize the inherent data structures among sensor measurement traces and then apply these models individually to guide the error detection of a sensor network. First, we propose a multivariate Gaussian model which explores the correlated data changes of a group of sensors. Second, we present a Principal Component Analysis （PCA） model which captures the sparse geometric relationship among sensors in a network. The PCA model is motivated by the fact that not all sensor networks have clustered sensor deployment and clear data correlation structure. Further, if the sensor data show non-linear characteristic, a traditional PCA model can not capture the data attributes properly. Therefore, we propose a third model which utilizes kernel functions to map the original data into a high dimensional feature space and then apply PCA model on the mapped linearized data. All these three models serve the purpose of capturing the underlying phenomenon of a sen

关键词： wireless sensor network faulty detection kernel Principal Component Analysis (PCA)

An efficient deep learning-assisted person re-identification solution for intelligent video surveillance in smart cities

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Frontiers of Computer Science 2023年第4期17卷 83-96页

作者： Muazzam MAQSOOD sadaf YASMIN Saira GILLANI Maryam BUKHARI Seungmin RHO Sang-Soo YEO Department of Computer Science COMSATS University IslamabadAttock CampusAttock 43600Pakistan Department of Computer Science Bahria UniversityLahore 54600Pakistan Department of Industrial Security Chung-Ang UniversitySeoul 06974Republic of Korea Department of Computer Engineering Mokwon UniversityDaejeon 35349Republic of Korea

Innovations on the Internet of Everything(IoE)enabled systems are driving a change in the settings where we interact in smart units,recognized globally as smart city ***,intelligent video-surveillance systems are critical to increasing the security of these smart *** precisely,in today’s world of smart video surveillance,person re-identification(Re-ID)has gained increased consideration by *** researchers have designed deep learningbased algorithms for person Re-ID because they have achieved substantial breakthroughs in computer vision *** this line of research,we designed an adaptive feature refinementbased deep learning architecture to conduct person *** the proposed architecture,the inter-channel and inter-spatial relationship of features between the images of the same individual taken from nonidentical camera viewpoints are focused on learning spatial and channel *** addition,the spatial pyramid pooling layer is inserted to extract the multiscale and fixed-dimension feature vectors irrespective of the size of the feature ***,the model’s effectiveness is validated on the CUHK01 and CUHK02 *** compared with existing approaches,the approach presented in this paper achieves encouraging Rank 1 and 5 scores of 24.6% and 54.8%,respectively.

关键词： Internet of Everything(IoE) visual surveillance systems big data security systems person re-identification(Re-ID) deep learning

A Hybrid System for Customer Churn Prediction and Retention Analysis via Supervised Learning

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Computers, Materials & Continua 2022年第9期72卷 4283-4301页

作者： Soban Arshad Khalid Iqbal Sheneela Naz sadaf Yasmin Zobia Rehman Department of Computer Science COMSATS UniversityIslamabadAttock CampusPakistan Department of Computer Science COMSATS UniversityIslamabadIslamabad CampusPakistan

Telecom industry relies on churn prediction models to retain their *** prediction models help in precise and right time recognition of future switching by a group of customers to other service *** not only contributes to the profit of an organization,but it is also important for upholding a position in the competitive *** the past,numerous churn prediction models have been proposed,but the current models have a number of flaws that prevent them from being used in real-world largescale telecom *** schemes,fail to incorporate frequently changing *** sparsity,noisy data,and the imbalanced nature of the dataset are the other main challenges for an accurate *** this paper,we propose a hybrid model,name as“A Hybrid System for Customer Churn Prediction and Retention Analysis via Supervised Learning(HCPRs)”that used Synthetic Minority Over-Sampling Technique(SMOTE)and Particle Swarm Optimization(PSO)to address the issue of imbalance class data and feature *** cleaning and normalization has been done on big Orange dataset contains 15000 features along with 50000 *** experiments are performed to test and validate the model on Random Forest(RF),Linear Regression(LR),Naïve Bayes(NB)and *** show that the proposed model when used with XGBoost classifier,has greater Accuracy Under Curve(AUC)of 98%as compared with other methods.

关键词： Telecom churn prediction data sparsity class imbalance big data particle swarm optimization

Mechanical properties of directionally solidified lead-antimony alloys

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International Journal of Minerals,Metallurgy and Materials 2011年第5期18卷 582-588页

作者： MevlüSahin hasan Kaya Department of Physics Faculty of Arts and SciencesNigde UniversityNigde 51200Turkey Department of Science Education Faculty of EducationErciyes UniversityKayseri 38039Turkey

The Pb-17wt% Sb alloy was directionally solidified under two solidification conditions：with different temperature gradients （G=0.93-3.67 K/mm） at a constant growth rate （V=17.50 λm/s） and with different growth rates （V=8.3-497 μm/s） at a constant temperature gradient （G=3.67 K/mm） in a Bridgman *** parameters,such as primary dendrite arm spacing （λ1）,secondary dendrite arm spacing （σ2）,and dendrite tip radius （R）,were *** microhardness （Hv） and ultimate tensile strength （λ） of the directional so-lidification samples were also *** influences of solidification and microstructure parameters on Hv and σwere *** results obtained in this work were compared with similar experimental researches in *** is shown that the Hv and σvalues increase with the increase of G and V,but decrease with the increase of λ1,λ2,and R.

关键词： lead-antimony alloy directional solidification microstructure mechanical properties

A Hybrid Circuit Breaker Based on Current Commutation Approach for Multi-feeder DC Railway Substations

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CSEE Journal of Power and Energy Systems 2019年第2期5卷 234-239页

作者： Saady hasan Department of Electrical Machine and Power Engineering Faculty of Engineering at Helwan Helwan UniversityEgypt

The paper presents an economic hybrid circuit breaker for limiting and interrupting the faults in DC railways substations. For fast fault current interruption, the hybrid breaker incorporates high speed mechanical contacts actuated by power semiconductor devices. Additionally, to avoid formation of electric arc, a commutation circuit is used to inject a counter current during fault interruption. In a real railway substation, each feeder is connected to the main DC bus through an expensive air magnetic DC circuit breaker and to an auxiliary DC bus through another expensive breaker. This leads to high cost especially in railway substation with multi feeders which are used to energize the vehicle transmission lines. In this paper, all DC breakers in DC railway substations are replaced by the suggested circuit breaker, which consists of a high speed mechanical contact with two semiconductor devices in each feeder and only one commutation circuit for injecting the counter current in all faulted feeders. The fault diagnosis is designed to detect the abnormal condition (current or voltage) in all feeders and direct the injected current from the commutation circuit to the faulted feeder only when the abnormal reaches a predetermine level. The suggested breaker is able to detect and interrupt any cascading of faults.

关键词： Arc-less circuit breaker operation fault current limiting and interruption hybrid DC circuit breaker railway substation

A Novel Cryptocurrency Prediction Method Using Optimum CNN

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Computers, Materials & Continua 2022年第4期71卷 1051-1063页

作者： Syed H.hasan Syeda Huyam hasan Mohammed Salih Ahmed Syed Hamid hasan Iowa State University AmesUSA University of Texas at Arlington USA Department of Computer Engineering College of Computer Science and Information TechnologyImam Abdulrahman Bin Faisal UniversityDammamSaudi Arabia Department of Information Systems Faculty of Computing and Information TechnologyKing Abdulaziz UniversityJeddahSaudi Arabia

In recent years,cryptocurrency has become gradually more significant in economic regions *** cryptocurrencies,records are stored using a cryptographic *** main aim of this research was to develop an optimal solution for predicting the price of cryptocurrencies based on user opinions from social *** is used as a marketing tool for cryptoanalysis owing to the unrestricted conversations on cryptocurrencies that take place on social media ***,this work focuses on extracting Tweets and gathering data from different sources to classify them into positive,negative,and neutral categories,and further examining the correlations between cryptocurrency movements and Tweet *** paper proposes an optimized method using a deep learning algorithm and convolution neural network for cryptocurrency prediction;this method is used to predict the prices of four cryptocurrencies,namely,Litecoin,Monero,Bitcoin,and *** results of analyses demonstrate that the proposed method forecasts prices with a high accuracy of about 98.75%.The method is validated by comparison with existing methods using visualization tools.

关键词： Cryptocurrency litecoin monero bitcoin ethereum twitter optimal CNN price prediction sentiment analysis

Breakage of drops and bubbles in a stirred tank： A review ofexperimental studies

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Chinese Journal of Chemical Engineering 2017年第6期25卷 698-711页

作者： Basim O. hasan Department of Chemical Engineering Technical University of Berlin 6ermany Department of Chemical Engineering AI-Nahrain University lraq

The rate of breakage of drops and bubbles(fluid particles) in stirred systems is of great consequence on mass,heat, and momentum transport phenomena. Therefore, over the years, the topic has gained a considerable attention from the researchers to study and characterize this phenomenon. In present work, the experimental studies of breakage phenomenon in a stirred tank in the last four decades were reviewed. The review highlighted the investigated experimental conditions and the major findings concerning the breakage mechanism and the effect of operating conditions. The discrepancy and contradictions of the outcomes of those studies were specified and discussed. Experimental observations and conclusions concerning the breakage characterization parameters,such as deformation, breakage probability, breakage time, and breakage location were presented and commented on. Possible future refinements and prospective were recommended. The review indicated that there are clear discrepancies and contradictions between previous studies regarding the effect of some operating parameters and the values of breakage time, breakage probability, number of daughter particles, and breakage location relative to the impeller. In addition, there are still many scientific gaps that need to be studied and characterized in future by overcoming specific experimental difficulties and uncertainties.

关键词： Drop Bubble Breakage Stirred tank Review Breakage rate

Cranial differences in three-toed jerboas(Dipodinae,Dipodidae,Rodentia)according to recent taxonomic revisions

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Current Zoology 2023年第4期69卷 475-490页

作者： Bader H.Alhajeri Zahraa hasan hasan Alhaddad Department of Biological Sciences Kuwait UniversitySafat13060Kuwait

Recent phylogenetic studies amended the taxonomy of three-toed jerboas(subfamily Dipodinae),including raising subspecies to full ***,we use geometric morphometrics to compare scaled-shape differences in dipodine crania while considering their revised *** sampled Dipus deasyi,*** halli,***,Jaculus blanfordi blanfordi,***,***,***,*** gerboa,***,and Stylodipus *** were not sexually *** allometry explained some of the shape variation,for example,reduced braincases in larger *** operational taxonomic unit pairs differed in both size and *** and Stylodipus clustered together based on their cranial *** differed from the aforementioned genera by its larger tympanic bulla,broader braincase,larger infraorbital foramen,along with reduced molars and *** orientalis differed from other Jaculus by its broader face versus reduced cranial *** blanfordi(subgenus Haltomys)resembles members of the subgenus Jaculus more than its consubgener(***).Jaculus loftusi,previously considered a synonym of ***,clearly differed from the latter by its shorter rostrum,smaller infraorbital foramen,and more caudolaterally expanded tympanic *** hirtipes,another recent synonym of ***,resembled *** more in scaled cranial shape than it did *** sagitta halli and *** were indistinguishable,but they clearly differed from ***(recently raised to full species)with the latter having a larger molar row,more inflated tympanic bulla,and shorter,slenderer *** explanations for detected cranial shape differences are considered,including diet and habitat(particularly substrate).

关键词： crania Dipus deasyi Jaculus hirtipes Jaculus loftusi jerboa Stylodipus andrewsi