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Coverless Image Steganography Based on Jigsaw Puzzle Image Generation

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Computers, Materials & Continua 2021年第5期67卷 2077-2091页

作者： Al Hussien Seddik saad M.S.Mohamed E.H.Hafez Department of Computer Science Faculty of ScienceMinia UniversityMinya61519Egypt Department of Mathematics College of ScienceTaif UniversityTaif21944Saudi Arabia Department of Mathematics Faculty of ScienceAl-Azher UniversityNasr City11884Egypt Department of Mathematics Faculty of ScienceHelwan UniversityCairoEgypt

Current image steganography methods are working by assigning an image as a cover file then embed the payload within it by modifying its pixels,creating the stego ***,the left traces that are caused by these modifications will make steganalysis algorithms easily detect the hidden payload.A coverless data hiding concept is proposed to solve this *** does not mean that cover is not required,or the payload can be transmitted without a ***,the payload is embedded by cover generation or a secret message mapping between the cover file and the *** this paper,a new coverless image steganography method has been proposed based on the jigsaw puzzle image generation driven by a secret ***,the image is divided into equal rows then further divided into equal columns,creating blocks(i.e.,sub-images).Then,according to secret message bits and a proposed mapping function,each block will have tabs/blanks to get the shape of a puzzle piece creating a fully shaped jigsaw puzzle *** that,the generated jigsaw puzzle image is sent to the *** results and analysis show a good performance in the hiding capacity,security,and robustness compared with existing coverless image steganography methods.

关键词： Coverless information hiding Jigsaw puzzle image image steganography data hiding

Catheter ablation for atrial fibrillation in heart failure:untying the Gordian knot

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Journal of Geriatric Cardiology 2021年第4期18卷 297-306页

作者： saad Javed Ioanna Koniari David Fox Chris Skene Gregory YH Lip Dhiraj Gupta Liverpool Centre for Cardiovascular Science University of LiverpoolLiverpool Heart and Chest HospitalLiverpoolUK Division of Cardiovascular Sciences University of ManchesterManchesterUK Cardiology Department University Hospital of ManchesterManchesterUK

Atrial fibrillation(AF) and heart failure(HF) are complex clinical entities that occur concomitantly in a significant population of patients, and their prevalence is rising in epidemic proportions. Traditionally, both rate and rhythm control strategies have been regarded as equivalent in the management of dysrhythmia in this AF-HF cohort with escalation of treatment largely guided by symptoms. Both disorders are involved in an elaborate pathophysiological interplay with shared cardiovascular risk factors that contribute to the development and sustenance of both AF and HF. Recent studies and continued development of evidence to support catheter ablation for AF has brought into question the traditional belief in equivalence between rate and rhythm control. Indeed, recent trials, in particular the CASTLE-AF(Catheter Ablation versus Standard Conventional Therapy in Patients with Left Ventricular Dysfunction and Atrial Fibrillation) study, suggest that catheter ablation for AF improves survival and rates of hospitalisation in patients with concomitant HF and AF, threatening a paradigm shift in the management of this patient cohort. The evident mortality benefit from clinical trials suggests that catheter ablation for AF should be considered as a therapeutic intervention in all suitable patients with the AF-HF syndrome as these patients may derive the greatest benefit from restoration of sinus rhythm. Further research is needed to refine the evidence base, especially to determine which subgroup of HF patients benefit most from catheter ablation and what is the optimal timing.

关键词： Catheter ablation for atrial fibrillation in heart failure:untying the Gordian knot

An efficient synthesis of bis(indolyl)methanes and N,N'-alkylidene bisamides by Silzic under solvent free conditions

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Chinese Chemical Letters 2016年第3期27卷 353-356页

作者： Hanan A.Soliman Ahmed Y.Mubarak saad S.Elmorsy Photochemistry Department National Research Centre Chemistry Department Faculty of ScienceMansoura University

An operationally simple and green method for the synthesis of a wide range of bis（indolyl）methanes,and N,N＇-alkylidene bisamides under mild conditions,with excellent yields using Silzic,has been *** improved method furnishes in good yields bis（indolyl）methanes derivatives starting from indole and aldehydes,or ketones,and N,N＇-alkylidene bisamides derivatives starting from acetamide and *** catalytic system was reused up to three times with the same efficiency.

关键词： Bis(indolyl)methanes N N'-alkylidenebisamides Acetamide Mild conditions Silzic

Modern comprehensive study of the W UMa system TY Boo

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Research in Astronomy and Astrophysics 2015年第4期15卷 501-516页

作者： Magdy M.Elkhateeb Mohamed Ibrahim Nouh Abdel-Naby S.saad Astronomy Department National Research Institute of Astronomy and Geophysics Physics Department College of ScienceNorthern Border University Mathematics Department Preparatory YearQassim University

New three color light curves of TY Boo were acquired during five nights from February to May 2006 in the BVR bandpass using a 50-cm F/8.4 Ritchey- Chr6tien telescope （Ba50） at the Baja Astronomical Observatory （Hungary）, with a 512×512 Apogee AP-7 CCD camera. A photometric solution of these light curves was obtained by means of the Wilson-Devinney code. The results showed that the less massive component is hotter than the more massive one, and the temperature difference between the components is △T -249 K. Long term investigation of the system based on all available data shows two stages of increase and a similar trend for decrease, which appears to be periodic behavior. A set of new light elements yields a new period （P = 0.3171506d） and shows a periodic decrease with the rate dP/dE -- 5.858×10^-12 d cycle-1, 6.742×10^-9 d yr-1 or 0.058 s century-1. The evolutionary status of the system is discussed.

关键词： binaries: eclipsing -- stars: evolution

Development of a Smart Technique for Mobile Web Services Discovery

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Computers, Materials & Continua 2021年第11期69卷 1483-1501页

作者： Mohamed Eb-saad Yunyoung Nam Hazem M.El-bakry samir Abdelrazek Department of Information Systems Faculty of Computers and InformationMansoura UniversityMansoura35516Egypt Department of Computer Science and Engineering Soonchunhyang UniversityAsan31538Korea

Web service(WS)presents a good solution to the interoperability of different types of systems that aims to reduce the overhead of high processing in a resource-limited *** the increasing demand for mobile WS(MWS),the WS discovery process has become a significant challenging point in the WS lifecycle that aims to identify the relevant MWSs that best match the service *** discovery process is a resource-consuming task that cannot be performed efficiently in a mobile computing environment due to the limitations of mobile ***,a cloud computing can provide rich computing resources for mobile environments given its unlimited and easily scalable *** paper proposes a semantic WS discovery and invocation framework in mobile environments based on cloud and a relationship-aware matchmaking *** discovery algorithm enriches MWS and user requests semantically with the functional and non-functional properties of Ontology Web Language for Services,such as Quality of Web Service,device context,and user *** WS repository is filtered based on logical reasoning and a parameter-based matching algorithm to minimize the matching space and improve runtime *** cosine similarity between the user request and services repository is then assessed to generate the most relevant *** relationships among concepts in the ontology are considered to improve the recall and precision *** the WS discovery process,users can invoke and test these services in a mobile environment through a dynamic user *** interface of the invocation process is changed according to the WS description *** application prototype is also developed to evaluate the framework based on a Cordova cross-mobile development framework.

关键词： Cloud web service web service discovery semantic matching mobile web service discovery

Signature of the 27-day variation in hemispheric sunspot activity and asymmetry during 2010-2015

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Research in Astronomy and Astrophysics 2021年第4期21卷 331-340页

作者： Prithvi Raj Singh Ahmad Islam saad Farid Tarun Kumar Pant Abhay Kumar Singh Department of Physics Banaras Hindu UniversityVaranasi-221005India Physics and Chemistry Department Faculty of EducationAlexandria UniversityAlexandria-21526Egypt Space Physics Laboratory VSSCThiruvananthapuram-695022India

In the present work,we study the time evolution,significance of the N-S asymmetry excesses presented as a function of the solar cycle and prominent rotational periods(~27 d)separately for the northern and southern *** have investigated short-term variations of the hemispheric solar activity(sunspot numbers and sunspot areas)during the time period 2010-2015,which covers the ascending and the maximum phase of solar cycle *** have implemented the Lomb-Scargle periodogram and continuous wavelet transform power spectrum techniques to study the time evolution and dominant rotational periods separately for the northern and southern hemispheres,and whole solar *** results showed that the northern hemisphere exhibited longer solar synodic periods than the southern hemisphere,indicating that the northern hemisphere has a lower rotation ***,the northern hemisphere was found to be dominant before transferring to the southern hemisphere during ***,the sunspot areas clearly demonstrated a two-peak structure of solar activity in the northern and southern hemispheres respectively during 2012 and *** statistical significance of the southern hemisphere affirmed enhanced excess during the maximum phase of solar cycle 24.

关键词： Sunspots Sunspot Area Asymmetry Solar Cycle

Wolbachia pipientis:A potential candidate for combating and eradicating dengue epidemics in Pakistan

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Asian Pacific Journal of Tropical Medicine 2015年第12期8卷 963-973页

作者： Uruj Tahir Umair Hassan Khan Muhammad saad Zubair Bahar-e-Mustafa Department of Environmental Sciences Fatima Jinnah Women University Department of Microbiology.University of Agriculture Faisalabad Department of Microbiology.Government College University Faisalabad

Dengue virus syndrome is an emerging global health challenge which is endemic in tropical countries like *** recent years dengue incidences have increased considerably in different areas of Pakistan with more sever impacts on urban and peri-urban *** review is an effort to highlight the changing epidemiology of dengue fever,role of Government of Pakistan in disease management and control using preventive and community based approaches in the ***,there is an emphasis on application of Wolbachia as novel,inexpeasive and environmentally benign candidate for control and eradication of dengue transmitting vectors.

关键词： Dengue Pakistan Antiviral agents Chemical methods

Threefold Optimized Forecasting of Electricity Consumption in Higher Education Institutions

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Computers, Materials & Continua 2022年第11期73卷 2351-2370页

作者： Majida Kazmi Hashim Raza Khan Lubaba Mohammad Hashir Bin Khalid saad Ahmed Qazi Faculty of Electrical and Computer Engineering NED University of Engineering and TechnologyKarachi75270Pakistan Neurocomputation Lab National Center of Artificial IntelligenceKarachi75270Pakistan

Energy management benefits both consumers and utility companiesalike. Utility companies remain interested in identifying and reducing energywaste and theft, whereas consumers’ interest remain in lowering their energyexpenses. A large supply-demand gap of over 6 GW exists in Pakistan asreported in 2018. Reducing this gap from the supply side is an expensiveand complex task. However, efficient energy management and distributionon demand side has potential to reduce this gap economically. Electricityload forecasting models are increasingly used by energy managers in takingreal-time tactical decisions to ensure efficient use of resources. Advancementin Machine-learning (ML) technology has enabled accurate forecasting ofelectricity consumption. However, the impact of computation cost affordedby these ML models is often ignored in favour of accuracy. This studyconsiders both accuracy and computation cost as concurrently significantfactors because together they shape the technology environment as well ascreate economic impact. Thus, a three-fold optimized load forecasting modelis proposed which includes (1) application specific parameters selection, (2)impact of different dataset granularities and (3) implementation of specificdata preparation. It deploys and compares the widely used back-propagationArtificial Neural Network (ANN) and Random Forest (RF) models for theprediction of electricity consumption of buildings within a university. In addition to the temporal and historical power consumption date as input parameters, the study also embeds weather data as well as university operationalcalendars resulting in improved performance. The outcomes are indicativethat the granularity i.e. the scale of details in data, and set of reduced and fullinput parameters impact performance accuracies differently for ANN and RFmodels. Experimental results show that overall RF model performed betterboth in terms of accuracy as well as computational time for a 1-min, 15-minand 1-h dataset

关键词： Electricity forecasting short term higher educational institution artificial neural network random forest accuracy computational time

Influences of processing parameters and heat treatment on microstructure and mechanical behavior of Ti-6Al-4V fabricated using selective laser melting

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Advances in Manufacturing 2022年第4期10卷 520-540页

作者： Qi-Dong Sun Jie Sun Kai Guo saad Waqar Jiang-Wei Liu Lei-Shuo Wang Key Laboratory of High Efficiency and Clean Mechanical Manufacture National Demonstration Center for Experimental Mechanical Engineering EducationSchool of Mechanical EngineeringShandong UniversityJinan250061People’s Republic of China Research Centre for Aeronautical Component Manufacturing Technology and Equipment Shandong UniversityJinan250061People’s Republic of China School of Energy and Power Engineering Shandong UniversityJinan250061People’s Republic of China School of Mechanical and Power Engineering Zhengzhou UniversityZhengzhou450001People’s Republic of China

Selective laser melting(SLM)has provided an alternative to the conventional fabrication techniques for Ti-6Al-4V alloy parts because of its flexibility and ease in creating complex ***,this study investigated the effects of the process parameters and heat treatment on the microstructure and mechanical properties of Ti-6Al-4V fabricated using *** influences of various process parameters on the relative density,tensile properties,impact toughness,and hardness of Ti-6Al-4V alloy parts were *** employing parameter optimization,a high-density high-strength Ti-6Al-4V alloy was fabricated by SLM.A relative density of 99.45%,a tensile strength of 1188 MPa,and an elongation to failure of 9.5%were achieved for the SLM-fabricated Ti-6Al-4V alloy with optimized *** effects of annealing and solution aging heat treatment on the mechanical properties,phase composition,and microstructure of the SLM-fabricated Ti-6Al-4V alloy were also *** ductility of the heat-treated Ti-6Al-4V alloy was *** applying a heat treatment at 850℃ for 2 h,followed by furnace cooling,the elongation to failure and impact toughness were found to be increased from 9.5%to 12.5%,and from 24.13 J/cm^(2)to 47.51 J/cm^(2),respectively.

关键词： Selective laser melting(SLM) Ti-6Al-4V alloy Heat treatment Microstructure Mechanical properties