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Performance evaluation of a novel rotational damper for structural reinforcement steel frames subjected to lateral excitations

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Earthquake Engineering and Engineering Vibration 2014年第1期13卷 75-84页

作者： M.sanati s.E.Khadem s.Mirzabagheri H.sanati M.Y.Khosravieh Faculty of Mechanical Engineering Tarbiat Modares University structural Engineering group Faculty of Civil and Environmental EngineeringTarbiat Modares University school of Mechanical Engineering College of engineeringUniversity of Tehran

In this study,a novel rotational damper called a Rotational Friction Viscoelastic Damper(RFVD) is *** viscoelastic pads are added to the Rotational Friction Damper(RFD) in addition to the friction discs used in this conventional ***,the amount of energy dissipated by the damper increases in low excitation *** fact,the input energy to the structure is simultaneously dissipated in the form of friction and heat by frictional discs and viscoelastic *** order to compare the performance of this novel damper with the earlier types,a set of experiments were carried *** to the test results,the RFVD showed a better performance in dissipating input energy to the structure when compared to the *** seismic behavior of steel frames equipped with these dampers was also numerically evaluated based on a nonlinear time history *** numerical results verifi ed the performance of the dampers in increasing the energy dissipation and decreasing the energy input to the structural *** order to achieve the maximum dissipated energy,the dampers need to be installed in certain places called critical points in the *** appropriate approach is presented to properly fi nd these ***,the performance of the RFVDs installed at these critical points was investigated in comparison to some other confi gurations and the validity of the suggested method in increasing the energy dissipation was confi rmed.

关键词： seismic excitations rotational friction-viscoelastic damper rotational damper friction pad viscoelastic material energy dissipation

Influence of Metallic substitutions on the Optical and Mechanical Properties of NLO Benzoyl glycine Crystals

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Journal of Materials science & Technology 2008年第6期24卷 891-894页

作者： T.Kishore Kumar s.Janarthanan s.M.Ravikumar s.Pandi M.Vimalan P.sagayaraj D.Prem Anand Department of Physics Presidency CollegeChennai-600005India Department of Physics Loyola CollegeChennai-600034India Department of Physics St.Xavier's CollegePalayamkottai-627002India

Benzoyl glycine （Bg） is a promising organic nonlinear optical （NLO） crystal, whose second harmonic generation （sHg） efficiency is much higher than that of KDP （potassium dihydrogen phosphate）. single crystals of pure, Cu2＋ and Cd2＋ doped Bg were grown by slow evaporation technique. Optically transparent and defect free single crystals of size up to 10 mm×15 mm×10 mm were harvested in a period of 40-60 days. The growth conditions of pure and doped crystals of Bg were optimized and the grown crystals were confirmed by single crystal XRD （X-ray diffraction）. The grown crystals were characterized by FTIR （Fourier transform infrared spectroscopy）, optical absorption and microhardness studies. The microhardness studies confirm that Bg has a moderate VHN （Vickers hardness number） value in comparison to *** organic NLO crystals. The efficiency of frequency doubling was measured for the using nd：YAg laser and the results were discussed.

关键词： Nonlinear optical crystal Crystal growth Doped single crystals FTIR VHN

Wide QRs complex tachycardia in a patient with wide QRs complex sinus rhythm due to left bundle branch block pattern

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Journal of geriatric Cardiology 2020年第8期17卷 530-532页

作者： András Vereckei Katalin Vadász András Zsáry 3^rd Department of Medicine Semmelweis UniversityBudapestHungary 2^nd Department of Medicine Semmelweis UniversityBudapestHungary

A 58-year-old man with hypertension and half a year ago documented left bundle branch block(LBBB)in his past history presented with progressive dyspnea.A pre-admission echocardiography showed severely depressed systolic left ventricular function[ejection fraction(EF)=27%],diffuse hypokinesis and dilated heart chambers consistent with dilated cardiomyopathy(DCM).

关键词： Dilated cardiomyopathy Electrocardiogram supraventricular tachycardia Ventricular tachycardia Wide QRs complex tachycardia

An Efficient Numerical scheme for Biological Models in the Frame of Bernoulli Wavelets

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Computer Modeling in Engineering & sciences 2023年第12期137卷 2381-2408页

作者： Fei Li Haci Mehmet Baskonus s.Kumbinarasaiah g.Manohara Wei gao Esin Ilhan Department of scientific Research Yunnan Normal UniversityKunming650500China Department of Mathematics and science Education Harran UniversitySanliurfa63050Türkiye Department of Mathematics Bangalore UniversityBengaluru560056India school of Information science and Technology Yunnan Normal UniversityKunming650500China Faculty of Engineering and Architecture Kirsehir Ahi Evran UniversityKırsehir40500Türkiye

This article considers three types of biological systems:the dengue fever disease model,the COVID-19 virus model,and the transmission of Tuberculosis *** new technique of creating the integration matrix for the Bernoulli wavelets is ***,the novel method proposed in this paper is called the Bernoulli wavelet collocation scheme(BWCM).All three models are in the form system of coupled ordinary differential equations without an exact *** systems are converted into a system of algebraic equations using the Bernoulli wavelet collocation *** numerical wave distributions of these governing models are obtained by solving the algebraic equations via the Newton-Raphson *** results obtained from the developed strategy are compared to several schemes such as the Runge Kutta method,and nd solver in mathematical *** convergence analyses are discussed through *** newly implemented Bernoulli wavelet method improves the accuracy and converges when it is compared with the existing methods in the literature.

关键词： Biological systems system of coupled ODEs bernoulli wavelets functional matrix collocation technique

Cretaceous volcanic-intrusive magmatism in western guangdong and its geological significance

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science China Earth sciences 2006年第7期49卷 696-713页

作者： s. Y. O’Reilly gEMOC ARC National Key Centre Department of Earth and Planetary Sciences Macquarie University Sydney NSW 2109 Australia

systematic zircon LA-ICPMs U-Pb dating reveals that Cretaceous volcanic-intrusive activities developed in western guangdong. Representative volcanic rocks, i.e. Maanshan and Zhougongding rhyodacites, have zircon U-Pb isotopic ages of 100±1 Ma, and the intrusive ones in-cluding the Deqing monzonitic granite body and the Xinghua granodiorite body in the shidong com-plex, as well as the Tiaocun granodiorite body in the guangping complex yield ages of 99±2 Ma, ca. 100 Ma, and 104±3 Ma respectively. The biotite-granites of the shidong complex main body (461±35 Ma) and that of the guangping complex (444±6 Ma) are Caledonian. In spite of the big time interval between Cretaceous volcanic-intrusive magmatisms and Caledonian intrusive ones, both of them are characterized by enrichment in Rb, Th, Ce, Zr, Hf, sm, depletion in Ba, Nb, Ta, P, Ti, Eu, and weakly REE tetrad effect. Eu negative anomalies are: Cretaceous volcanic rocks (Eu/Eu*=0.74), Cretaceous intrusive rocks (Eu/Eu*=0.35―0.58), Caledonian biotite granites (Eu/Eu*=0.31―0.34). studies of sr-nd isotope data show that all these igneous rocks have high initial 87sr/86sr ratios (0.7105―0.7518), and low εnd(t) values (?7.23―?11.39) with their nd two-stage model ages ranging from 1.6―2.0 ga, which suggest that they all derived from the Proterozoic crustal basement of southeast China. The occurrence of Cretaceous volcanic-intrusive magmatisms in western guangdong is related with the important lithospheric extension event in southeast China (including Nanling region) at ca. 100 Ma. The “volcanic line” defined by the large scale Mesozoic intermediate-acidic volcanic magmatisms in southeast China may further extend to the southwest margin of Nanling region.

关键词： Cretaceous, volcanic-intrusive rocks, zircon U-Pb dating, sr-nd isotope, western guangdong.

Feature Extraction and Classification of Plant Leaf Diseases Using Deep Learning Techniques

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Computers, Materials & Continua 2022年第10期73卷 233-247页

作者： K.Anitha s.srinivasan Department of Electronics and Communication Engineering Saveetha School of EngineeringSaveetha Institute of Medical and Technical Sciences(SIMATS)Saveetha UniversityThandalamChennai602105India Instituteof Bio-Medical Engineering Saveetha School of EngineeringSaveetha Institute of Medical and Technical Sciences(SIMATS)Saveetha UniversityThandalamChennai602105India

In India’s economy, agriculture has been the most significantcontributor. Despite the fact that agriculture’s contribution is decreasing asthe world’s population grows, it continues to be the most important sourceof employment with a little margin of difference. As a result, there is apressing need to pick up the pace in order to achieve competitive, productive,diverse, and long-term agriculture. Plant disease misinterpretations can resultin the incorrect application of pesticides, causing crop harm. As a result,early detection of infections is critical as well as cost-effective for *** diagnose the disease at an earlier stage, appropriate segmentation of thediseased component from the leaf in an accurate manner is critical. However,due to the existence of noise in the digitally captured image, as well asvariations in backdrop, shape, and brightness in sick photographs, effectiverecognition has become a difficult task. Leaf smut, Bacterial blight andBrown spot diseases are segmented and classified using diseased Apple (20),Cercospora (60), Rice (100), grape (140), and wheat (180) leaf photos in thesuggested work. In addition, a superior segmentation technique for the ROIfrom sick leaves with living backdrop is presented here. Textural features of thesegmented ROI, such as 1st and 2nd order WPCA Features, are discoveredafter segmentation. This comprises 1st order textural features like kurtosis,skewness, mean and variance as well as 2nd procedure textural features likesmoothness, energy, correlation, homogeneity, contrast, and entropy. Finally,the segmented region of interest’s textural features is fed into four differentclassifiers, with the Enhanced Deep Convolutional Neural Network provingto be the most precise, with a 96.1% accuracy.

关键词： Convolutional neural network wavelet based pca features leaf disease detection agriculture disease remedies bat algorithm

In situ magnesium calcium phosphate cements formation: From one pot powders precursors synthesis to in vitro investigations

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Bioactive Materials 2020年第3期5卷 644-658页

作者： M.A.goldberg P.A.Krohicheva A.s.Fomin D.R.Khairutdinova O.s.Antonova A.s.Baikin V.V.smirnov A.A.Fomina A.V.Leonov I.V.Mikheev N.s.sergeeva s.A.Akhmedova s.M.Barinov V.s.Komlev A.A.Baikov Institute of Metallurgy and Materials science Russian Academy of Sciences119334Leninsky av49MoscowRussian Federation M.V.Lomonosov Moscow state University Department of Chemistry119991Leninskie Gory1MoscowRussian Federation Federal state Budgetary Institution National Medical Research Radiological Center of the Ministry of Health of the Russian Federation 1252842nd Botkinsky pass.3MoscowRussian Federation

Calcium phosphate cements are of great interest for researchers and their applications in medical practice ***,they have a number of drawbacks including the insufficient level of mechanical properties and low degradation ***(MgNH4PO4)-based cements,which grew in popularity in recent years,despite their neutral pH and acceptable mechanical performance,release undesirable NH4+ions during their *** issue could be avoided by replacement of ammonia ions in the cement liquid with sodium,however,such cements have a pH values of 9–10,leading to ***,the main goal of this investigation is to optimize the composition of cements to achieve the combination of desirable properties:neutral pH,sufficient mechanical properties,and the absence of cytotoxicity,applying Na2HPO4-based cement *** this purpose,cement powders precursors in the CaO-MgO-P2O5 system were synthesized by one-pot process in a wide composition range,and their properties were *** optimal performance was observed for the cements with(Ca+Mg)/P ratio of 1.67,which are characterized by newberyite phase formation during setting reaction,pH values close to 7,sufficient compressive strength up to 22±3 MPa(for 20 mol.%of Mg),dense microstructure and adequate matrix properties of the *** set of features make those materials promising candidates for medical applications.

关键词： Magnesium calcium phosphate cement stanfieldite Whitlockite Newberyite Brushite In vitro investigations

A study of Making Iron Aluminide Alloy Powders with New Rotating Electrode Technology

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厦门大学学报（自然科学版） 2002年第S1期41卷 107-108页

作者： s s LIAN M L sHI Department of Materials science & Engineering National Taiwan UniversityDepartment of Materials Science & Engineering National Taiwan University Taipei ChinaTaipei China

A new process was used for producing FeAl alloy pow de rs with double consumable rotating electrodes and the powders made in this appar atus were analyzed. In this new technology, tungsten rod serves as a cathode ele ctrode, while the alloy rod as an anode electrode. The conventional rotating ele ctrode process must have an anode with pre-melting alloys; however, in this new process, using pure iron as cathode electrode and pure aluminum as anode electr ode can eliminate the step of pre-melting. The effects of process variables, which include electrode rotational speed, a nd electrode diameter of the mean particle diameter were determined. Results showed that both the rotational speed and diameter of electrodes would a ffect the mean diameter of particles. There are three kinds of powders with diff erent composition produced in this study and the possible mechanisms are discuss ed. The process parameters and volume mean diameter of the powders have been cor related to find an experimental equation. The results show that when the rotational speed and the diameter of the anode el ectrode are increased, the powders size will decrease. However, the powders size will increase with cathode electrode.

关键词： A study of Making Iron Aluminide Alloy Powders with New Rotating Electrode Technology

Basin geomorphology and Drainage Morphometry Parameters Used as Indicators for groundwater Prospect: Insight from geographical Information system(gIs) Technique

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Journal of Earth science 2014年第6期25卷 1018-1032页

作者： Kumar Avinash B Deepika K s Jayappa National Centre for Antarctic & Ocean Research Department of Marine geology Mangalore University

Influence of structural and lithological controls of various drainage patterns and their stream orientations（for 2nd, 3rd and 4th order steams） were identified to evaluate the direction and controlling factors of drainage network. To investigate the prospect of groundwater, hydrogeomorphological features of river basin viz. Mulki-Pavanje were identified and mapped. To evaluate the characteristics of the basin, different morphometric parameters（linear, areal and relief） were computed in sub-basin wise（sB-I to-VII）. The linear parameters suggest drainage network is controlled by geomorphology. The form factor（Ff）, elongation ratio（Re） and circularity ratio（Rc） suggest that the basin is in an elongated shape. The drainage density（Dd） indicates resistant/permeable strata under medium-dense vegetation with moderate relief. The areal parameters of the sub-basins（except sBI and Ⅲ） indicates moderate ground-slopes associated with moderately permeable rocks, which promote moderate run-off and infiltration. Drainage texture（T） of the whole basin indicates coarse texture while the sB-I, and Ⅲ showing an intermediate texture. The relief parameters namely ruggedness number（Rn） infers low basin relief and poor drainage density. To identify the most deficit/surplus zones of groundwater suitable weightages were assigned to the hydrogeomorphological units and morphometric parameters. The study reveal that the basin manifest that sB-Ⅲ shall be most deficit zone of groundwater, whereas sB-VII, VI and V are found to show increase in groundwater potentiality. groundwater prospect area in this basin is estimated to be 7% area under poor, 44% area under moderate and 49% area under good to excellent. This paper demonstrated the potential application of geographical information system（gIs） techniques to evaluate the groundwater prospect in absence of traditional groundwater monitoring data.

关键词： hydrogeomorphology drainage morphometry prioritization groundwater prospect Mulki-Pavanje River Basin remote sensing