检索结果-南通市图书馆

Multifunctional, Sustainable, and Biological Non-Ureolytic Self-Healing Systems for Cement-Based Materials

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Engineering 2022年第6期8卷 217-237页

作者： Mohammad Fahimizadeh Pooria Pasbakhsh Lee Sui Mae Joash Ban Lee Tan r.k.singh raman School of Engineering Monash University MalaysiaBandar Sunway 47500Malaysia School of Science Monash University MalaysiaBandar Sunway 47500Malaysia Tropical Medicine and Biology Multidisciplinary Platform Monash University MalaysiaBandar Sunway 47500Malaysia Department of Chemical Engineering&Department of Mechanical and Aerospace Engineering Monash UniversityClaytonVIC 3168Australia

Microbially induced calcium carbonate(CaCO_(3))precipitation(MICP)has been investigated as a sustain-able alternative to conventional concrete remediation methods for improving the mechanical properties and durability of concrete *** date,urea-dependent MICP is the most widely employed MICP pathway in biological self-healing concrete research as its use has resulted in efficient CaCO_(3) precipita-tion ***_(3) is a byproduct of ureolysis,and can be hazardous to cementitious structures and the health of various ***,non-ureolytic bacterial concrete self-healing systems have been developed as eco-friendly alternatives to urea-dependent self-healing ***-ureolytic pathways can improve the physical properties of concrete samples and incorporate the use of waste materials;they have the potential to be cost-effective and ***,they can be applied in terrestrial and marine *** date,research on non-ureolytic concrete self-healing systems has been scarce compared to that on ureolytic *** article discusses the advances and challenges in non-ureolytic bacterial concrete self-healing studies and highlights the directions for future research.

关键词： Self-healing concrete Mechanical properties Durability Non-ureolytic pathways Cement composite Sustainability

Graphene-calcium carbonate coating to improve the degradation resistance and mechanical integrity of a biodegradable implant

在线全文

学校读者我要写书评

暂无评论

Journal of Magnesium and Alloys 2024年第1期12卷 394-404页

作者： Lokesh Choudhary Parama Chakraborty Banerjee r.k.singh raman Derrek E.Lobo Christopher D.Easton Mainak Majumder Frank Witte Jörg F.Löffler Department of Mechanical and Aerospace Engineering Monash UniversityClayton CampusMelbourneVIC 3800Australia Department of Chemical and Biological Engineering Monash UniversityClayton CampusMelbourneVIC 3800Australia Nanoscale Science and Engineering Laboratory(NSEL) Bldg 37Monash UniversityClayton CampusMelbourneVIC 3800Australia CSIrO Materials Science and Engineering Bayview AvenueClaytonVIC 3168Australia Julius Wolff Institute and Berlin Brandenburg Center for regenerative Therapies Charité–Universitätsmedizin BerlinAugustenburger Platz 113353 BerlinGermany Laboratory of Metal Physics and Technology Department of MaterialsETH Zurich8093 ZurichSwitzerland

Biodegradable implants are critical for regenerative orthopaedic procedures,but they may suffer from too fast corrosion in human-body *** necessitates the synthesis of a suitable coating that may improve the corrosion resistance of these implants without compromising their mechanical *** this study,an AZ91 magnesium alloy,as a representative for a biodegradable Mg implant material,was modified with a thin reduced graphene oxide(rGO)-calcium carbonate(CaCO_(3))composite *** analytical and in-vitro electrochemical characterization reveals that this coating significantly improves the corrosion resistance and mechanical integrity,and thus has the potential to greatly extend the related application field.

关键词： Graphene coating Biodegradable implant Hydroxyapatite Corrosion Magnesium alloy

key Management Using Chebyshev Polynomials for Mobile Ad Hoc Networks

在线全文

学校读者我要写书评

暂无评论

China Communications 2017年第11期14卷 237-246页

作者： k.r.ramkumar raman singh Chitkara University Chandigarh - Patiala National Highways (NH 64)Patiala - 140401 Punjab India Thapar University Patiala- 147004 Punjab India

A dedicated key server cannot be instituted to manage keys for MANETs since they are dynamic and unstable. The Lagrange's polynomial and curve fitting are being used to implement hierarchical key management for Mobile Ad hoc Networks(MANETs). The polynomial interpolation by Lagrange and curve fitting requires high computational efforts for higher order polynomials and moreover they are susceptible to runge's phenomenon. The Chebyshev polynomials are secure, accurate, and stable and there is no limit to the degree of the polynomials. The distributed key management is a big challenge in these time varying networks. In this work, the Chebyshev polynomials are used to perform key management and tested in various conditions. The secret key shares generation, symmetric key construction and key distribution by using Chebyshev polynomials are the main elements of this projected work. The significance property of Chebyshev polynomials is its recursive nature. The mobile nodes usually have less computational power and less memory, the key management by using Chebyshev polynomials reduces the burden of mobile nodes to implement the overall system.

关键词： chebyshev polynomials interpolation secret sharing key management

Understanding the anti-corrosion characteristics of a newly synthesized Schiff's base: an experimental and computational approach

在线全文

学校读者我要写书评

暂无评论

Corrosion Communications 2022年第3期7卷 51-62页

作者： raman kumar Gurmeet singh Department of Chemistry University of Delhi Department of Chemical and Biomolecular Engineering Yonsei University Pondicherry University

This paper presents an economically viable and sustainable method to combat depletion of extensively used mild steel alloy in industries exposed to a stagnant 0.5 mol/L sulphuric acid（H2SO4） environment via a newly synthesized and characterized inhibitor namely 3-（2-amino-3-methylphenyl）imino)methyl)benzaldehyde（AMMB）. The fabrication of this additive was performed at room temperature（298 k） using eco-friendly solvents and reactants. The highest protection efficiency recorded was 98.73% at 298 k temperature. Comprehensive nature of the corrosion inhibition mechanism was ascertained using state of the art electrochemical（galvanostatic polarization, LPr, and EIS） and morphological（ATr, AFM, SEM-EDS） studies. These investigations also revealed the formation of complexes between metal and inhibitor molecules. The complexes formed on the metal substrate encase the entire surface, which accounts for the observed high inhibition efficiency. The quantum mechanical modeling of AMMB molecule and temperature kinetics study supplemented the predicted results from preceding techniques.

关键词： Polarization techniques Corrosion Density functional theory Impedance Atomic force microscopy Surface characterization

Prediction of Alzheimer’s Using random Forest with radiomic Features

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Computer Systems Science & Engineering 2023年第4期45卷 513-530页

作者： Anuj singh raman kumar Arvind kumar Tiwari kNIT Sultanpur Sultanpur228118India

Alzheimer’s disease is a non-reversible,non-curable,and progressive neurological disorder that induces the shrinkage and death of a specific neuronal population associated with memory formation and *** is a frequently occurring mental illness that occurs in about 60%–80%of cases of *** is usually observed between people in the age group of 60 years and *** upon the severity of symptoms the patients can be categorized in Cognitive Normal(CN),Mild Cognitive Impairment(MCI)and Alzheimer’s Disease(AD).Alzheimer’s disease is the last phase of the disease where the brain is severely damaged,and the patients are not able to live on their *** is an approach to extracting a huge number of features from medical images with the help of data characterization ***,105 number of radiomic features are extracted and used to predict the alzhimer’*** paper uses Support Vector Machine,k-Nearest Neighbour,Gaussian Naïve Bayes,eXtreme Gradient Boosting(XGBoost)and random Forest to predict Alzheimer’s *** proposed random forest-based approach with the radiomic features achieved an accuracy of 85%.This proposed approach also achieved 88%accuracy,88%recall,88%precision and 87%F1-score for AD ***,it achieved 72%accuracy,73%recall,72%precisionand 71%F1-score for AD *** and it achieved 69%accuracy,69%recall,68%precision and 69%F1-score for MCI *** comparative analysis shows that the proposed approach performs better than others approaches.

关键词： Alzheimer’s disease radiomic features cognitive normal support vector machine mild cognitive impairment extreme gradient boosting random forest

Oxide ancillary ligand-based europium β-diketonate complexes and their enhanced luminosity

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

rare Metals 2021年第10期40卷 2873-2881页

作者： Devender singh Shri Bhagwan Anuj Dalal kapeesha Nehra raman kumar Saini kapoor singh Anura Priyajith Simantilleke Sumit kumar Ishwar singh Department of Chemistry Maharshi Dayanand UniversityRohtak 124001India Centre de Fisica Universidade of MinhoBraga 4710057Portugal Department of Chemistry DCR University of Science and TechnologyMurthal 131039India

Ternary materials of europium complex with2,2,6,6-tetramethyl-3,5-heptanedione(tmhd) ligand and aqua ligand as ancillary ligands have been prepared and characterized for various optoelectronic *** of hydrated complex [Eu(tmhd)_(3)(H_(2)O)_(2)] proceeded with triphenylphosphine oxide(TPPO) and pyridine-N-oxide(PNO) ancillary ligands were studied to develop novel complexes. The prepared complexes show good thermal stability. A comparative investigation of preparedmaterials[Eu(tmhd)_(3)(H_(2)O)_(2)],[Eu(tmhd)_(3)(TPPO)_(2)] and [Eu(tmhd)_(3)(PNO)_(2)] was conducted for their luminescent behaviors in order to obtain the role of ancillary ligand in the enhancement of illumination amount generated from europium(Eu^(3+)) ion. Color coordinates of prepared ternary complexes such as[Eu(tmhd)_(3)(H_(2)O)_(2)]with(x = 0.54,y = 0.32),[Eu(tmhd)_(3)(TPPO)_(2)] with(x = 0.56, y = 0.32) and[Eu(tmhd)_(3)(PNO)_(2)] with(x = 0.57, y = 0.33) indicated that these materials exhibited bright red emission in visible region spectrum. The complexes show a proficient energy transport pathway from the ligands to the innermost Eu^(3+)by means of an ancillary ligand-sensitized luminescence process. Interaction between the metal and ligand results in a distinguished effect on quantum efficiency(η) as well as on Judd–Ofelt intensity factor(Ω_(2)) of the prepared materials.

关键词： Ternary Eu^(3+)complexes red emissive materials Photoluminescence Quantum efficiency Judd-Ofelt intensity Optoelectronic devices

Driving Style recognition System Using Smartphone Sensors Based on Fuzzy Logic

在线全文

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2021年第11期69卷 1967-1978页

作者： Nidhi kalra raman kumar Goyal Anshu Parashar Jaskirat singh Gagan Singla Department of Computer Science and Engineering Thapar Institute of Engineering and TechnologyPatiala147001PunjabIndia Computer Science and Engineering University Institute of Engineering and TechnologyPanjab University160014ChandigarhIndia

Every 24 seconds,someone dies on the road due to road accidents and it is the 8th leading cause of death and the first among children aged 15–29 years.1.35 million people globally die every year due to road traffic *** additional 20–50 million suffer from non-fatal injuries,often resulting in longterm *** costs around 3%of Gross Domestic Product to most countries,and it is a considerable economic *** governments have taken various measures such as better road infrastructures and strict enforcement of motor-vehicle laws to reduce these ***,there is still no remarkable reduction in the number of *** ensure driver safety and achieve vision of zero accidents,there is a great need to monitor drivers’driving *** of the existing driving behavior monitoring solutions are based on expensive hardware *** most people are using smartphones in the modern era,a system based on mobile application is proposed,which can reduce the cost for developing intelligent transport systems(ITS)to a large *** this paper,we utilize the accelerometer sensor data and the global positioning system(GPS)sensor deployed in smartphones to recognize driving and speeding events.A driving style recognition system based on fuzzy logic is designed to classify different driving styles and control reckless driving by taking the longitudinal/lateral acceleration and speed as input ***,the proposed system uses fuzzy logic rather than taking the crisp values of the *** indicate that the proposed system can classify reckless driving based on fuzzy logic and,therefore,reduce the number of accidents.

关键词： Fuzzy logic accelerometer global positioning system driving style

Stimulated raman Scattering in a Weakly Polar Ⅲ-Ⅴ Semiconductor： Effect of dc Magnetic Field and Free Carrier Concentration

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 2007年第8期24卷 2245-2248页

作者： M. singh P. Aghamkar P. k. Sen Department of Applied Physics Guru Jambheshwar University of Science and Technology Hisar-125001 India Department of Applied Physics S.G.S. Institute of Technology and Science 23-Park Road Indore-452003 India

Using the hydrodynamic model of semiconductor plasmas, we perform an analytical investigation of stimulated raman scattering （SITS） of an electromagnetic pump wave in a transversely magnetized weakly polar semicon- ductor arising from electron-density perturbations and molecular vibrations of the medium both produced at the longitudinal optical phonon frequency. Assuming that the origin of SItS lies in the third-order susceptibility of the medium, we investigate the growth rate of Stokes mode. The dependence of stimulated raman gain on the external dc magnetic field strength and free carrier concentration is reported. The possibility of the occurrence of optical phase conjugation via SItS is also studied. The steady-state raman gain is found to be greatly enhanced by the presence of the strong external dc magnetic field.

关键词： Stimulated raman Scattering Weakly Polar Semiconductor

Obtaining Crisp Priorities for Triangular and Trapezoidal Fuzzy Judgments

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computer Systems Science & Engineering 2022年第4期41卷 157-170页

作者： raman kumar Goyal Jaskirat singh Nidhi kalra Anshu Parashar Gagan Singla Sakshi kaushal Computer Science and Engineering Department Thapar Institute of Engineering and TechnologyPatialaPunjabIndia Computer Science and Engineering University Institute of Engineering and TechnologyPanjab UniversityChandigarhIndia

This paper proposes anoptimal fuzzy-based model for obtaining crisp priorities for Fuzzy-AHP comparison *** judgments cannot be given for real-life situations,as most of these include some level of fuzziness and *** these situations,judgments are represented by the set of fuzzy *** of the fuzzy optimization models derive crisp priorities for judgments repre-sented with Triangular Fuzzy Numbers(TFNs)*** do not work for other types of Triangular Shaped Fuzzy Numbers(TSFNs)and Trapezoidal Fuzzy Numbers(TrFNs).To overcome this problem,a sum of squared error(SSE)based optimization model is *** some other methods,the proposed model derives crisp weights from all of the above-mentioned fuzzy judgments.A fuzzy number is simulated using the Monte Carlo method.A threshold-based constraint is also applied to minimize the deviation from the initial *** Algorithm(GA)is used to solve the optimization *** have also conducted casestudiesto show the proposed approach’s advantages over the *** show that the proposed model outperforms other models to minimize SSE and deviation from initial ***,the proposed model can be applied in various real time scenarios as it can reduce the SSE value upto 29%compared to the existing studies.

关键词： Analytic hierarchy process comparison matrices priority vectors fuzzy judgments triangular fuzzy numbers triangular-shaped fuzzy numbers trapezoidal fuzzy numbers