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Effects of Curing Conditions on strength Development of high strength Concrete

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China Ocean Engineering 1997年第1期12卷 99-108页

作者： Cai, YB Kwan, kh UNIV hONG KONG DEPT CIVIL & STRUCT ENGNHONG KONGHONG KONG

This paper presents the results of a series of studies on the influence of curing conditions on the strength development of high strength concrete. The 1-, 3-, 7-, 14- and 28-day strengths of four different mixes of Grade 75 similar to 80 concrete, with or without pulverized fuel ash and/or condensed silica fume, under five different curing regimes were investigated. It is revealed that the curing conditions have significant influence on both the short term and long term strength development of the concrete and that concrete mixes of the same grade but containing different mineral admixtures show distinct favour for a curing regime. These results will be helpful for evaluating suitable curing methods for high strength concrete with different mix proportions.

关键词： curing condition high strength concrete strength development mineral admixture mix proportion

Optical properties and radiative rates of Nd^(3+) doped zinc-sodium phosphate glasses

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Journal of Rare Earths 2019年第3期37卷 253-259页

作者： A.A.El-Maaref shimaa Badr kh.s.shaaban E.A.Abdel Wahab M.M.ElOkr Physics Department Faculty of Science Al-Azhar University Modern Academy for Engineering & Technology Chemistry Department Faculty of Science Al-Azhar University

Preparation using melt quenching technique and optical characterizations of Nd^(3+) doped Zn-Na phosphate glasses are presented. The structure of the present glasses was studied using X-ray diffraction and FT-IR spectroscopy. UV-vis spectra of the present glasses were analyzed at different concentrations of Nd_2 O_3. The effect of neodymium concentration on the density and energy band gap was investigated. The density of the present glasses slightly increases with the increasing of Nd_2 O_3. A small variation of energy band gap with the increasing of neodymium content is observed as well, while E_g values decrease with the increase of Nd_2 O_3 content. The E_g values lie between 4.36 and 4.69 eV. Based on the measured optical spectra, Judd-Ofelt theory was used to determine the optical parameters such as line strengths, optical intensity parameters(Ω_t), transition probabilities, and transition lifetimes. hypersensitive transitions were identified in the absorption spectrum, the greatest line strengths are recorded at the transitions^2 G_(7/2)+ ~4 G_(5/2), ~4 s_(3/2) + ~4 F_(7/2) and ~4 D_(1/2) + ~4 D_(3/2)+ ~4 D_(5/2) + ~2 I_(11/2) with wavelengths of 580, 475 and 355 nm,respectively. Lifetimes of the important ~4 F_(3/2) laser-level were determined; which show decreasing trend with the increasing of Nd_2 O_3 content and are found to be between 0.838 and 1.595 ms. The uncertainty of the present results was estimated. The RMs deviations were determined, which show lower values than those in the literature.

关键词： Phosphate glass UV-vis spectroscopy Judd-Ofelt Radiative rates Rear earth ions

An Effective hybridization of Quantum-based Avian Navigation and Bonobo Optimizers to solve Numerical and Mechanical Engineering Problems

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Journal of Bionic Engineering 2023年第3期20卷 1361-1385页

作者： Mohammad h.Nadimi-shahraki Faculty of Computer Engineering Najafabad BranchIslamic Azad UniversityNajafabad***Iran Big Data Research Center Najafabad BranchIslamic Azad UniversityNajafabad***Iran

hybrid metaheuristic algorithms play a prominent role in improving algorithms' searchability by combining each algorithm's advantages and minimizing any substantial shortcomings. The Quantum-based Avian Navigation Optimizer Algorithm (QANA) is a recent metaheuristic algorithm inspired by the navigation behavior of migratory birds. Different experimental results show that QANA is a competitive and applicable algorithm in different optimization fields. however, it suffers from shortcomings such as low solution quality and premature convergence when tackling some complex problems. Therefore, instead of proposing a new algorithm to solve these weaknesses, we use the advantages of the bonobo optimizer to improve global search capability and mitigate premature convergence of the original QANA. The effectiveness of the proposed hybrid Quantum-based Avian Navigation Optimizer Algorithm (hQANA) is assessed on 29 test functions of the CEC 2018 benchmark test suite with different dimensions, 30, 50, and 100. The results are then statistically investigated by the Friedman test and compared with the results of eight well-known optimization algorithms, including PsO, kh, GWO, WOA, CsA, hOA, BO, and QANA. Ultimately, five constrained engineering optimization problems from the latest test suite, CEC 2020 are used to assess the applicability of hQANA to solve complex real-world engineering optimization problems. The experimental and statistical findings prove that the proposed hQANA algorithm is superior to the comparative algorithms.

关键词： Optimization Metaheuristic algorithms Evolutionary algorithm Quantum-based avian navigation optimizer algorithm Engineering optimization problems,Bionic algorithm

A survey on the Metaheuristics for Cryptanalysis of substitution and Transposition Ciphers

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Computer systems science & Engineering 2021年第10期39卷 87-106页

作者： Arkan kh shakr sabonchi Bahriye Akay Computer Engineering Department Erciyes UniversityKayseri38039MelikgaziTurkey

This paper presents state-of-art cryptanalysis studies on attacks of the substitution and transposition ciphers using various metaheuristic *** cryptanalysis methods employ an exhaustive search,which is computationally ***,metaheuristics have attracted the interest of researchers in the cryptanalysis *** algorithms are known for improving the search for the optimum solution and include Genetic Algorithm,simulated Annealing,Tabu search,Particle swarm Optimization,Differential Evolution,Ant Colony,the Artificial Bee Colony,Cuckoo search,and Firefly *** most important part of these various applications is deciding the fitness function to guide the *** review presents how these algorithms have been implemented for cryptanalysis *** paper highlights the results and findings of the studies and determines the gaps in the literature.

关键词： Cryptanalysis metaheuristic algorithms substitution cipher transposition cipher

PARTICULATE sUsPENsION FLOW INDUCED BY sINUsOIDAL PERIsTALTIC WAVEs ThROUGh ECCENTRIC CYLINDERs： ThREAD ANNULAR

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International Journal of Biomathematics 2013年第4期6卷 113-137页

作者： kh. s. MEkhEIMER Y. ABD ELMABOUD A. I. ABDELLATEEF Mathematics Department Faculty of Science Al-Azhar University Nasr City 11448 Cairo Egypt Mathematics Department Faculty of Science Tail University Hawia (888) Tail Saudi Arabia Mathematics Department Faculty of Science and Arts Khulais King Abdulaziz University (KAU) Saudi Arabia Mathematics Department Faculty of Science Al-Azhar University (Assiut Branch) Assiut Egypt Basic science Department Higher Institute of Engineering Shorouk City Cairo Egypt

This paper describes a new model for obtaining analytical solutions of peristaltic flow through eccentric annuli. A mathematical model of peristaltic pumping of a fluid mixture （as blood model） in a circular eccentric cylinders is presented and it is motivated due to the fact that thread injection is a promising method for placing medical implants within the human body with minimum surgical trauma. For the eccentric annuli, the inner cylinder is rigid and moving with a constant velocity V, and the outer one is hollow flexible cylinder that has a sinusoidal wave traveling down its wall. The coupled differential equations for both the fluid and the particle phases have been solved by using two methods and the expressions for the velocity distribution of fluid and particle phase, flow rate, pressure drop, friction forces at the inner and outer cylinders have been derived. The results obtained are discussed in brief. The significance of the particle concentration and the eccentricity parameter as well as the nature of the basic flow has been well explained.

关键词： Eccentric annulus flows particle fluid suspension peristalsis endoscope

hump nosed viper bite in sri Lanka-descriptive observational study of 1543 cases

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Asian Pacific Journal of Tropical Medicine 2010年第11期3卷 902-905页

作者： Wijewantha hs sellahewa kh National hospital of sri Lanka Colombo 10Sri Lanka

Objective:To identify the clinical manifestations of hump nosed viper envenomation and to recognize the available treatment methods to prevent ***:Descriptive observational study involving a series of 1 543 patients admitted with hump nosed viper bite to 5 major hospitals in sri Lanka was *** collection was done consecutively during February 1990 and February *** hypnale,identification of the biting snake was made by the corresponding author after visual examination of the dead or live snakes,which were brought to ***:sixty seven(4.34%) patients developed systemic effects and two (0.1%) patients died due to effects of envenomation or complications of *** effects varied from coagulopathy,nephropathy to some neurological *** nine (3.8%) patients had only coagulopathy and they received either,intravenous isotonic saline to ensure adequate urine out put i.e.0.5 mL/kg /hour or 15 mL/kg of fresh frozen plasma(FFP). None of the patients that had coagulopathy developed renal *** of the sample by mildly venomous species of hypnale may have contributed to the low incidence of systemic ***:It is likely that early hydration with normal saline or FFP can prevent acute renal *** showed a tendency for early correction of *** of FFP in hump nosed viper envenomation is worth studying in randomized double blind controlled clinical trials.

关键词： snake bites hump nosed viper Clinical manifestations Prevention of complications Fresh frozen plasma

Orange dye polyaniline composite based impedance humidity sensors

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Chinese Physics B 2013年第1期22卷 161-166页

作者： Muhammad Tariq saeed Chani kh. s. Karimov F. A. khalid s. Z. Abbas M. B. Bhatty GIK Institute of Engineering sciences and Technology Topi 23640 Khyber Pakhtunkhwa Pakistan Center of Excellence for Advanced Materials Research (CEAMR) King Abdulaziz University Jeddah 21589 P.O. Box 80203 Saudi Arabia Physical Technical Institute Aini St. 299/1 Dushanbe 734063 Tajikistan

This study presents the fabrication and investigation （PANI） composite films. A blend of 3 wt.% OD with 1 of humidity sensors based on orange dye （OD） and polyaniline wt.% PANI was prepared in 1 ml water. The composite films were deposited on glass substrates between pre-deposited silver electrodes. The gap between the electrodes was 45 um. The sensing mechanism was based on the impedance and capacitance variations due to the absorption/desorption of water vapor. It was observed that with the increase in relative humidity （Rh） from 30% to 90%, the impedance decreases by 5.2 × 10^4 and 8.8 × 10^3 times for the frequencies of 120 hz and 1 khz, respectively. The impedance-humidity relationship showed a more uniform change compared to the capacitance-humidity relationship in the Rh range of 30% to 90%. The consequence of annealing, measuring frequency, response and recovery time, and absorption-desorption behavior of the humidity sensor were also discussed in detail. The annealing resulted in an increase in sensitivity of up to 2.5 times, while the measured response time and recovery time were 34 s and 450 s, respectively. The impedance-humidity relationship was simulated.

关键词： organic-organic composite humidity sensor polyaniline orange dye

Drawing insights from pion parton distributions

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Chinese Physics C 2020年第3期44卷 12-17页

作者： Minghui Ding khépani Raya Daniele Binosi Lei Chang C.D.Roberts s.M.schmidt school of Physics Nankai UniversityTianjin 300071China European Centre for Theoretical studies in Nuclear Physics and Related Areas(ECT^*)and Fondazione Bruno Kessler Villa Tambosi Strada delle Tabarelle 286I-38123 Villazzano(TN)Italy school of Physics Nanjing UniversityNanjingJiangsu 210093China Institute for Nonperturbative Physics Nanjing UniversityNanjingJiangsu 210093China Institute for Advanced simulation Forschungszentrum Jülich and JARAD-52425 JülichGermany

A symmetry-preserving continuum approach to the two valence-body bound-state problem is used to calculate the valence, glue and sea distributions within the pion; unifying them with, inter alia, electromagnetic pion elastic and transition form factors. The analysis reveals the following momentum fractions at the scale ζ2:= 2GeV :〈xvalence〉 = 0.48（3）, 〈xglue〉 = 0.41（2）, 〈xsea〉 = 0.11（2）;and despite hardening induced by the emergent phenomenon of dynamical chiral symmetry breaking, the valence-quark distribution function, qπ（x）, exhibits the x ≈ 1 behaviour predicted by quantum chromodynamics（QCD）. After evolution to o ζ = 5.2 GeV, the prediction for qπ（x） matches that obtained using lattice-regularised QCD. This confluence should both stimulate improved analyses of existing data and aid in planning efforts to obtain new data on the pion distribution functions.

关键词： pion parton distribution bound state Dyson-schwinger equations

ThE　sTRUCTURAL　ELUCIDATION　AND　ABsOLUTE　CONFIGURATIONs　OF　TWO　NEW　POLYOXYGENATED　CYCLOhEXENEs　FROM　UVARIA　GRANDIFLORA　ROXB．

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Chinese Chemical Letters 1996年第3期7卷 241-244页

作者： Pan, XP Yu, DQ Lee, kh BEIJING UNION MED COLL BEIJING 100050PEOPLES R CHINA UNIV N CAROLINA SCH PHARMNAT PROD LABDIV MED CHEM & NAT PRODCHAPEL HILLNC 27599 ChINEsE ACAD MED sCI INST MAT MEDBEIJING 100050PEOPLES R CHINA

Two new polyoxygenated cyclohexenes,named uvarigranol E (I) andF(VII),were isolated from the rhizome of Uvaria grandiflora. On the basis ofspectral analysis and chemical derivatizations, including preparation of Mosheresters,the structures of I and VII were established as IR-acetoxymethyl-l,2sdihydroxy-3 R,6s-dibenzoyloxy-cyclohex-4-ene and IR-hydroxymethyl-l,2sdihydroxy-3R,6s-dibenzoyloxy cyclohex-4-ene.

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