bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abrupt transition due to non-local cascade propagation in multiplex systems
Authors: Artime Oriol , De Domenico Manlio 
Published: August 2020

Abstract
Multilayer systems are coupled networks characterized by different contexts (layers) of interaction and have gained much attention recently due to their suitability to describe a broad spectrum of empirical complex systems. They are very fragile to percolation and first-neighbor failure propagation, but little is known about how they respond to non-local disruptions, as it occurs in failures induced by flow redistribution, for example. Acknowledging that many socio-technical and biological systems sustain a flow of some physical quantity, such as energy or information, across the their components, it becomes crucial to understand when the flow redistribution can cause global cascades of failures in order to design robust systems, to increase their resilience or to learn how to efficiently dismantle them. In this paper we study the impact that different multiplex topological features have on the robustness of the system when subjected to non-local cascade propagation. We first numerically demonstrate that this dynamics has a critical value at which a small initial perturbation effectively dismantles the entire network, and that the transition appears abruptly. Then we identify that the excess of flow caused by a failure is, in general, more homogeneously distributed the networks in which the average distance between nodes is small. Using this information we find that aggregated versions of multiplex networks tend to overestimate robustness, even though to make the system more robust can be achieved by increasing the number of layers. Our predictions are confirmed by simulated cascading failures in a real multilayer system.
Controlled growth of Mo2C pyramids on liquid Cu surface
Authors: Fan Yixuan , Huang Le , Geng Dechao , Hu Wenping 
Published: August 2020

Abstract
Precise spatial control of 2D materials is the key capability of engineering their optical, electronic, and mechanical properties. However, growth of novel 2D Mo2C on Cu surface by chemical vapor deposition method was revealed to be seed-induced 2D growth, limiting further synthesis of complex Mo2C spatial structures. In this research, we demonstrate the controlled growth of Mo2C pyramids with numerous morphologies, which are characterized with clear terraces within the structures. The whole evolution for Mo2C pyramids in the coursed of CVD process has been detected, posing significant potential in probing growth mechanism. The formation of the Mo2C pyramids arises from the supersaturation-induced nucleation and concentration-gradient driven diffused growth of a new Mo2C layer on the edged areas of intrinsic ones, as supported by STEM imaging. This work provides a novel Mo2C-based pyramid structure and further reveals a sliding growth mechanism, which could offer impetus for the design of new 3D spatial structures of Mo2C and other 2D materials.
Photo-induced doping effect and dynamic process in monolayer MoSe2
Authors: Yang Qian , Xue Yongzhou , Chen Hao , Dou Xiuming , Sun Baoquan 
Published: August 2020

Abstract
Dynamic processes of electron transfer by optical doping in monolayer MoSe2 at 6 K are investigated via measuring time resolved photoluminescence (PL) traces under different excitation powers. Time-dependent electron transfer process can be analyzed by a power-law distribution of t
−α
with α = 0.1–0.24, depending on the laser excitation power. The average electron transfer time of approximately 27.65 s is obtained in the excitation power range of 0.5 to 100 μW. As the temperature increases from 20 to 44 K, the energy difference between the neutral and charged excitons is observed to decrease.
Numerical Investigation of Mixing Performance for a Vertical Turbulence Mixer
Authors: Ya MAO , Zhang Di , Xiong FAN , Lv Yinlei , Chen Zuobing 
Published: August 2020

Abstract
In this work, discrete element method (DEM) was employed to analyze mixing performance of a vertical turbulence mixer. The lacey mixing index was used to quantify mixing degree while a mixing rate was proposed to evaluate mixing speed. Several typical structural and operating parameters affecting mixing performance was investigated including initial loading pattern, rotational speed of stirring shaft and filling level. Results showed that mixing of top-bottom loading is faster than that of side-side loading. Comparing with another factor, stirring shaft rotating speed and filling level had more significant influence. A nearly linear growth and an almost linear decline relationships with mixing rate was found for the rotary speed and filling level respectively. A higher rotational speed or a lower filling level could help form a more intensive granular turbulent flow, resulting in faster mixing. Application of this work provides instruction to optimization of geometry and parameters of mixing systems to improve the quality of the mixing process.
Error Analysis of Distribution Curve
Authors: Zhang Xue-mei , Li Dong , Ma Qing-hua , Jing-yuan HAO 
Published: August 2020

Abstract
11 sets of microscopical data from one same briquette samples have been converted into the Pseudo Strength Index PSI curves, each curve is consisted of 37 points. PSI curves have been used to illustrate the procedures of analyzing and calculating the error. This study shown that even in each PSI curve, there always are same points with the point error greater than 3s, that it is, however, impossible to determine which curve is an “abnormal curve” based on the characteristic (number, size and location) of abnormal points. Because Euclid distance converts the error of a curve into the error of a point, it must first calculate the Euclid distance for the series sets of PSI curves. All 11 Euclid distances is less than the distance limit error of 3s. Therefore, there are no abnormal curves in 11 PSI curves evaluated.
Methane Hydrate Formation Behavior in the Presence of Selected Amino Acids
Authors: Shanker Pandey Jyoti , Jouljamal Daas Yousef , Paul Karcz Adam , Solms Nicolas von 
Published: August 2020

Abstract
Industrial-scale capture, storage, and transport of gases and gas mixtures, such as natural gas, CH4, and CO2 in the form of gas hydrate, is an attractive and feasible solution. However, low formation rate and low water-to-hydrate conversion make it challenging to adopt at commercial scale. Selection of an appropriate chemical as hydrate promoter is crucial to the success of such technologies. Amino acids are seen as potential chemicals to use in such applications due to their environmentally benign nature. However, there are uncertainties around their behavior and classification, since their thermodynamic and kinetic effects on gas hydrates are not well established. In this study, we have identified the kinetics of select amino acids (L-valine, L-methionine, L-histidine, and L-arginine) in methane hydrate formation. Results indicate that hydrophobicity of amino acids plays an important role in methane hydrate kinetics. L-methionine and L-valine show maximum normalized gas uptake and lowest induction time compared to L-histidine and L-arginine.
Preparation and characterization of hydroxyapatite powder and study of hydroxyapatite - alumina Composite
Authors: Saeed Ghazi K. , Essa Abbas F. , Said Saja Abdul-Ammer 
Published: August 2020

AbstractHydroxyapatite powder Ca10(PO4)6(OH)2was prepared locally from Iraqi beef bones, and characterization the powder as well as studied purity. A composite of hydroxyapatite-alumina was also prepared with a ratio of alumina 0,5,10,15,20,25% wt. Use polyethylene glycol as a binder with 1% wt by dissolving polyethylene glycol with ethanol (1g: 100ml) at 40 °C and using a magnetic stirrer to obtain a homogeneous solution for the material. Then drying the powder and pressing to prepare compound samples, after that heat treatment at 1350°C for three hours. The physical and mechanical properties studied such as density, porosity, water absorption ratio, hardness and compression resistance, as well as X-ray diffraction and X-ray florescence. X-ray diffraction analysis showed that the hydroxyapatite phase was stabilized for all prepared samples before and after heat treatment with chemical form Ca10(PO4)6(OH)2, the hydroxyapatite showed a stabilization in phase before and after heat treatment without decomposition into different components.
Synthesis and characterization of PVA-Graphene-Ag nanocomposite by using laser ablation technique
Authors: Mohammed Musaab Khudhur , Al-Dahash Ghaleb , Al-Nafiey Amer 
Published: August 2020

Abstract
The PVA-G-Ag nanocomposite have been synthesized effectively by pulsed laser ablation liquid (PLAL) as a considered to be environmentally friendly and free of residues from chemical reactions. The high excellence silver plate (99.99%) and graphite plate (99.99%) was immersed in the polyvinyl alcohol (PVA) solution and irradiated with the Nd-YAG laser at wavelength 1064 nm, power 160 mJ for the silver plate and 80mJ for graphite plate, reiteration rate 6 Hz, 10 ns pulse width and 300 pules for graphite plate and 700 pulse for silver plate. The pure of PVA, PVA-Graphene and PVA-Graphene-Ag nanocomposite were investigated using UV-VIS spectroscopy, FTIR and SEM. The absorption spectra of PVA-Graphene-Ag nanocomposite show the presence of two peaks one 0.4 at 272 and second 0.47 at 403 nm. The optical energy gap (Eg) decreased from 5eV of a pure PVA to 4.6eV of a PVA-G-Ag for indirect allowed transition and therefore, decreased from 4.4eV of a pure PVA to 4.1eV of a PVA-G-Ag for indirect forbidden transition. The transmittance and absorption coefficient have been determined. The SEM images confirmed that homogenous composite without aggregation of the components. The average size of nanoparticles of GNPs and AgNPs for PVA-G and PVA-G-Ag nanocomposite was 130 and 115 nm respectively. The FTIR has demonstrated that the connection between the graphene, silver and polymer network was enough to have stable nanocomposite. This investigation demonstrates that the pulse laser ablation decent instrument to decorated metals on the graphene with the presence of the polymer.
Study the Structural and Optical Properties Pure Copper Sulfide (CuS) Films Prepared by Pulsed Laser Deposition (PLD)
Authors: Chloob Meriam K , Hussain Saleem A 
Published: August 2020

Abstract
In this research, thin film copper sulfide (CuS) were prepared by the pulse laser deposition (PLD) on glass substrate with different thicknesses. The structural and optical properties of copper sulfide thin films were studied and the results of X-ray diffraction (XRD) were analysis. It was found that CuS films have a polycrystalline structure with hexagonal system. The optical properties of the CuS films were studied by measuring and calculating Transmittance and absorbance spectrum respectively within the wavelength range (300-1100) nm. The results of the absorbance spectrum showed that absorbance of the films increase with an increase in the number of pulses (increasing thickness) and that the type of the electronic transition are allowed direct type. The energy gap values between (2.2-2.9) eV, and the it decrease with an increasing of thickness.
Preparation and characterization of (WO3:Co3O4) nano catalyst for fuel cell application
Authors: Mohammed Haleemah J. 
Published: August 2020

Abstract
This research focused on preparing the (WO3: Co3O4) nano catalyst by an electrochemical deposition technique, the electrochemical deposition cell consists of (WO3: Co3O4) electrode as an anode, mesh stainless steel electrode as a cathode and an aqueous solution as an electrolyte. (WO3: Co3O4) were grown on mesh stainless steel electrode, and XRD was used for characterization of nano catalyst, the topography properties were studied by atomic force microscopy (AFM), study the characterization of the electrochemical parameters. For this cell in terms of the impact of hydrogen volume on current, voltage, As well as the study of the effective results of the different concentration electrolyte arrangements extending from 0.14 M to 0.28 M KOH.
Encryption and Steganography a secret data using circle shapes in colored images
Authors: Al-Kateeb Zeena N. , Al-Shamdeen Muna Jaffer , Al-Mukhtar Farah Saad 
Published: August 2020

Abstract
Since the earliest times, people have used the encryption and hiding data to achieve a safe and reliable transfer of important data. This paper propesed a new method for encrypting important data based on the circular shapes information that extracted from the cover image, The encryption process is done using an update of a well known traditional method with simple calculations taking advantage of the coordinates of the center of the main circle as keys extracted from the cover image to reduce the number of keys exchanged between the sender and the recipient and to increase the level of security and confidentiality. The hiding process of the encrypted data is done in pixels that located in the circular areas of the cover image and in three forms of concealment, which providing second encryption, choosing the hiding form depending on the appearing sequence of the character in the text, which makes decode the secure data will be so difficult, the experiments showed that the proposed method was achieved excellent encryption and hiding depending on the coefficients Peak Signal to Noise Ratio analyses (PNSR), Mean Square Error (MSE), and other measurements. The proposed method achieves a complete data recovery ratio where it was Bit Error Rate BER=0.
Review of Different Combinations of Facial Expression Recognition System
Authors: Abd_Almuhsen F. Almudhafer , Khalaf Zainab A. 
Published: August 2020

Abstract
The facial expression recognition (FER) system is a classifier system that attempts to recognize facial expressions based on the analysis of emotion behaviour on the face. The FER system can be implemented by using one classifier or combining multi feature extraction and/or multi classifiers. In general, FER is used with one classifier system to find the best label. Although a classification system is commonly used to find the most likely facial expression, it still produces substantial numbers of errors due to several factors that influence the FER result, such as data quantity, and environmental conditions (i.e. illumination and noise). Therefore, combined multi feature extraction methods and/or multi classifier systems are useful to avoid the single classifier errors. Multi feature extraction or a multi classifier system combination are used to take advantage of different system hypotheses to find an accurate result. This paper is a survey of the latest system combination techniques being used to enhance the classification performance in the FER system; the most recent studies are presented.
Image Classification based on CBIR
Authors: Ali Shaker K. , Sadoon Salah A. 
Published: August 2020

Abstract
In this paper, we present a new way to classify four types of images (Car accidents, Fire, Abnormal objects in street and Digs) which will be sent to four government places; Civil Defence, police station and Municipal. The classification method depends on the Content-Based Image Retrieval (CBIR), where we use a new method. In this method, we use a combination of three methods to extract features from an image; Single Value Decomposition (SVD), Edge Histogram Descriptor (EHD) and Color Auto-Correlogram for Extraction Features. You will use these features to find the closest similarities to the query image from the database images by selecting the closest 3 images, then choosing the class to which the closest two images belong to the retrieved. The combined method showed 100% accuracy in training phase and 100% test phase accuracy.
Performance analysis of Google’s Quick UDP Internet Connection Protocol under Software Simulator
Authors: Albasrawi Saif Talib 
Published: August 2020

Abstract
The QUIC protocol (Quick UDP Internet Connection) is a transport based over UDP Protocol (User Datagram Protocol) that provides safe, reliable and fast service on the Internet. Google proposed it to solve the problem of network delay. It is efficient, fast, and takes up fewer resources. The QUIC gathers the advantages of both TCP and UDP. QUIC is a user-level protocol running on top of UDP, which considered by IETF (Internet Engineering Task Force). Google assumes the response time of page load was short so that end-user performance was better. In this paper, the results presented on a local test using NS-3 (network simulator version 3) that allows QUIC output to test and design choices and possible limitations present the description of the functionalities and the main assumptions of the internet QUIC.
A Prediction of Grain Yield Based on Hybrid Intelligent Algorithm
Authors: Saleh Ibrahim Ahmed , Alawsi Wasan Abdallah , Alsaif Omar Ibrahim , Alsaif Khalil 
Published: August 2020

Abstract
The prediction is most important goals in economic quantitative studies, it basis in design and plan future economic policies properly process over forecasting accuracy. This paper is aiming at the problem salp swarm algorithm (SSA) for predicting grain yield is prone to fall into the local optimal problem. An improved SSA is proposed with combine with back propagation neural network. Using the different advantages of SSA algorithm in global search capabilities, combining the two for further optimize the weight, improve the accuracy and robustness of the grain yield prediction model. The specific implementation is selected from 1963 to 2013.
These methods are used to define agricultural datasets that supports crop growth decision for grain product and its influencing factors were tested as a data set.
The results show that, the improved salp swarm optimization can be classified as a good predict tool for the domestic food production trend in recent years compared with the SSA. This paper briefly introduces three artificial methods BP neural networks, SSA and improved SSA optimization algorithm. The natural behavior of salp, barrel-shaped plankton that are mostly water by weight optimization and combined with mixed-group of intelligent algorithm are simulated. The simulation results of grain production prediction illustrate that the predict precision of the improved SSA is much higher than of both conventional BPNN and SSA techniques and it’s very efficient and practicable.
Feature Extraction Methods: A Review
Authors: Mutlag Wamidh K. , Ali Shaker K. , Aydam Zahoor M. , Taher Bahaa H. 
Published: August 2020

Abstract
Feature extraction is the main core in diagnosis, classification, clustering, recognition, and detection. Many researchers may by interesting in choosing suitable features that used in the applications. In this paper, the most important features methods are collected, and explained each one. The features in this paper are divided into four groups; Geometric features, Statistical features, Texture features, and Color features. It explains the methodology of each method, its equations, and application. In this paper, we made acomparison among them by using two types of image, one type for face images (163 images divided into 113 for training and 50 for testing) and the other for plant images(130 images divided into 100 for training and 30 for testing) to test the features in geometric and textures. Each type of image group shows that each type of images may be used suitable features may differ from other types.
Three terms of derivative free projection technique for solving nonlinear monotone equations
Authors: Mahdi M M , Shiker M A K 
Published: August 2020

Abstract
The derivative-free projection technique is one of the efficient methods for solving nonlinear monotone equations. In this study, three terms of the derivative-free projection method with a monotone line search technique is presented. This method based on extension of a conjugate gradient descent and a developed gradient projection method to solve the nonlinear system of monotone equations. The proposed method can be used for large scale equations due to limited memory requirement. We investigated the global convergence of the suggested approach without requiring differentiability and also the equation is Lipschitz continuous. The numerical results showed that the new algorithm is efficient and promised.
Rényi Entropy for Mixture Model of Multivariate Skew Laplace distributions
Authors: Abid Salah H. , Quaez Uday J. 
Published: August 2020

Abstract
Rényi entropy is an important concept developed by Rényi in information theory. In this paper, we study in detail this measure of information in cases multivariate skew Laplace distributions then we extend this study to the class of mixture model of multivariate skew Laplace distributions. The upper and lower bounds of Rényi entropy of mixture model are determined. In addition, an asymptotic expression for Rényi entropy is given by the approximation. Finally, we give a real data example to illustrate the behavior of entropy of the mixture model under consideration.
Laguerre and Touchard Polynomials for Linear Volterra Integral and Integro Differential Equations
Authors: Abdullah Jalil T. , Ali Haleema S. 
Published: August 2020

Abstract
In this paper, efficient numerical methods are given to solve linear Volterra integral (VI) equations and Volterra Integro differential (VID) equations of the first and second types with exponential, singular, regular and convolution kernels. These methods based on Laguerre polynomials (LPs) and Touchard polynomials (TPs) that convert these equations into a system of linear algebraic equations. The results are compared with one another method and with each other. The results show that these methods are applicable and efficient. In addition, the accuracy of solution is presented and also the calculations and Graphs are done by using matlab2018 program.
Using Modified Conjugate Gradient Method to Improve SCA
Authors: Khalaf Ayad Hamad , Mitras Ban Ahmed 
Published: August 2020

Abstract
This research is to improve Sine - Cosine Algorithm (SCA) that is like any other intelligent techniques that encounter some problem such as slow convergence and the dropping in local solution. To overcome these problems. SCA has been developed and improved through three directions, First: Hybrid of SCA with Modified conjugate gradient method (MCG) that has improved through that derivation of parameter of new conjugate factor (βnew) and attest its characteristic such as descent and global to construct improve algorithm called SCA-MCG. The second direction was a hybrid of SCA with classic optimization methods such as conjugate gradient (CG) algorithm to construct SCA-CG, and parallel Tangent (PT) algorithm to construct SCA-PT. Third combining both previous methods, using the Hybrid value with SCA to construct SCA-CG-PT Algorithm of high quality accounts in all directions mentioned above. To improve the initial population which randomly generated by using excellent characteristics of MCG-CG-PT as well as using this improvement as initial population for SCA. Numerical results have proved the efficiency of improved Algorithm and the results was excellent if we compared with SCA. In addition, we got optimum global values for most functions by achieving functions minimum.
Qualitative Analysis and Traveling wave Solutions for the Nonlinear Convection Equations with Absorption
Authors: Abed Bashayir N. , Majeed Salam J. , Aal-Rkhais Habeeb A. 
Published: August 2020

AbstractWe discuss qualitative behavior of the solutions for the nonlinear parabolic equation which modeling nonlinear convection equation with absorption. This model represents the movement of growing population that is ruled by convection process. In this paper, we concentrate on proving the existence of traveling wave solutions for the nonlinear convection-reaction equations. In addition, we consider the model when the speed of advective wave may breakdown and the problem has a shock wave solution. The mathematical interesting of the waves comes from the behaviors of singular differential equation and discussing the stability of the solution.