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Science China Mathematics 1999年第3期42卷 225-237页

作者：周勇孙六全 Paul S.F.YIP Department of Statistics University of Hong Kong Hong Kong China

The local behavior of oscillation modulus of the product-limit (PL) process and the cumulative hazard process is investigated when the data are subjected to random censoring. Laws of the iterated logarithm of local oscillation modulus for the PL-process and the cumulative hazard process are established. Some of these results are applied to obtain the almost sure best rates of convergence for various types of density estimators as well as the Bahadur-Kiefer type process.

关键词： censorship oscillation modulus product-limit process cumulative hazard process law of the iterated logarithm (LIL).

STUDY ON THE FOUNDATION modulus OF ELASTIC TWO-LAYERED SYSTEM UNDER RIGID PAVEMENT SLAB

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Journal of Southeast University(English Edition) 1989年第2期6卷 81-87页

作者：赵■ 陈荣生 Communication Department of Jiangsu Province Department of Civil Engineering

Based on the hypothesis of elastic two-layered foundation system under in-finite slab with known values of thicknesses of various layers and slab modulus,a programADMODE for evaluating foundation modulus is worked out by putting the inverse com-putation idea for moduli of various layers of foundation into an optimization problem.The validities of the theory and program have been checked and verified by taboratorytest.Besides,the foundation modulus have also been computed with this program by usingthe data obtained from Tai-Zhou experimental road.Through regression analyses,theempirical formulas for computing the increasing multiples of the moduli of subgrade andbase course are presented.

关键词： rigid pavements optimization theory/fundation modulus

Enhancement of Elastic modulus of Epoxy Resin with Carbon Nanotubes

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World Journal of Nano Science and Engineering 2011年第1期1卷 1-6页

作者： Vijay Kumar Srivastava 不详

Nanocomposites consisting of multiwall carbon nanotubes (MWCNT) and epoxy resin were produced by a standard calendaring technique. In this study, 3% multiwall carbon nanotube particles were dispersed in epoxy resin by weight to produce the multiwall carbon nanotubes/epoxy composite. Nanohardness and Raman spectroscopy tests were used to obtain the modulus of elasticity and Raman intensity of MWCNTs/ epoxy resin composite. The results show that the Raman intensity increased with the increase of Raman shift and Raman intensity also affected with the reinforcement of multiwall carbon nanotubes and 1% exposure of laser power. Also, nanohardness increased with increase of modulus of elasticity, which indicated that the toughness of epoxy resin improved with the addition of multiwall carbon nanotubes.

关键词： Epoxy Resin Multiwall Carbon Nanotubes Nanohardness Raman Spectroscopy modulus of Elasticity

A Finite Element Study of Elastic-Plastic Hemispherical Contact Behavior against a Rigid Flat under Varying modulus of Elasticity and Sphere Radius

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Engineering（科研） 2010年第4期2卷 205-211页

作者： Prasanta Sahoo Biplab Chatterjee 不详

The present study considers a finite element analysis of elastic-plastic axi-symmetric hemispherical contact for a frictionless deformable sphere pressed by a rigid flat. The material of the sphere is modeled as elastic perfectly plastic. Analysis is carried out to study the effect of varying modulus of elasticity and sphere radius in wide range of dimensionless interference until the inception of plasticity as well as in plastic range. Results are compared with previous elastic-plastic models. It is found that materials with Young’s modulus to yield strength (E/Y) ratio less than and greater than 300 show strikingly different contact phenomena. The dependency of E on dimensionless interference at which the plastic region fully covers the surface is observed. However with different radius, finite element study exhibits similar elastic-plastic phenomena.

关键词： Elastic-plastic Contact Sphere against Flat ANSYS modulus of Elasticity Sphere Radius

Evaluating the Subgrade Reaction modulus Variations with Soil Grains Shape in Coarse-Grained Soils Using Genetic Algorithm

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Open Journal of Geology 2020年第2期10卷 111-123页

作者： Pouya Salari Naser Hafezi Moghaddas Gholam Reza Lashkaripour Mohammad Ghafoori Faculty of Science Ferdowsi University of Mashhad Mashhad Iran

Subgrade reaction modulus (Ks) is one of the main factors in evaluating engineering properties of soils for structural calculations and operations. So, many studies have been performed on the effect of other soil geotechnical parameters on it. One is the effect of soil grains shape on engineering properties of soils, especially Ks. The aim of the present research is to evaluate the effect of soil grains shape on Ks for coarse-grained soils of the west of Mashhad, Iran. For this purpose, 20 PLTs were performed on coarse-grained soils of the west of Mashhad and Ks amounts were determined. Then, flakiness and elongation of the samples measured and changes of Ks by soil grain shape were evaluated. The results showed the strength dependency of Ks to grain forms which an increase in flakiness and elongation indices leads to a decrease in Ks. Therefore, it is necessary to reduce Ks estimated form empirical relationships for flaky and elongated soils. So, by writing a genetic algorithm-based program to find the optimal relationship between the grain shape and the subgrade reaction coefficient, a valid equation for correcting the results from previous empirical equations was presented.

关键词： Subgrade Reaction modulus (Ks) Flakiness Test Elongation Test Plate Load Test (PLT) Genetic Algorithm

Resilient modulus of Compacted Lateritic Soils from Senegal at OPM Conditions

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Geomaterials 2013年第4期3卷 165-171页

作者： Fatou Samb Meissa Fall Yves Berthaud Makhaly Ba Laboratoire d’ Alembert—Université Pierre et Marie Curie Paris France Laboratoire de Mécanique et Modélisation—UFR Sciences de l’ Ingénieur Université de Thiès Thiès Sénégal

Repeated load triaxial tests were performed on five compacted gravel lateritic soils collected from different locations in Senegal: Sébikotane, Dougar, Pa Lo, Mont-Rolland and Ngoundiane. The study revealed that resilient modulus decreases with the increase of the bulk and deviatoric stress in constant confining pressure. In addition, resilient modulus increases with the percentage of cement for appreciably equal contents of moisture. This effect tends to stop for higher stress. Besides, correlations were made with some models of resilient modulus such as the Uzan-Witczack model (Witczack and Uzan, 1988 [1]) and the National Highway Research Program (NCHRP) model (2004 [2]). The study confirms that both models give very good results with the best correlations being obtained with the Uzan-Witczack model.

关键词： Gravel Lateritic Soils Resilient modulus Mechanical Behaviour Pavement Cyclic Triaxial Test Mechanistic Design

Assessment of Rock Mass Quality and Deformation modulus by Empirical Methods along Kandiah River, KPK, Pakistan

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Open Journal of Geology 2018年第10期8卷 947-964页

作者： Mian Sohail Akram Kamran Mirza Muhammad Zeeshan Muhammad Asad Jabbar Institute of Geology University of the Punjab Lahore Pakistan

The pivotal aim of this study is to evaluate the rock mass characterization and deformation modulus. It is vital for rock mass classification to investigate important parameters of discontinuities. Therefore, Rock Mass Rating (RMR) and Tunneling quality index (Q) classification systems are applied to analyze 22 segments along proposed tunnel routes for hydropower in Kandiah valley, Khyber Pakhtunkhwa, Pakistan. RMR revealed the range of fair to good quality rocks, whereas Q yielded poor to fair quality rocks for investigated segments of the rock mass. Besides, Em values were acquired by empirical equations and computer-aided program RocLab, and both methods presented almost similar variation trend of their results. Hence, the correlations of Em with Q and RMR were carried out with higher values of the regression coefficient. This study has scientific significance to initially understand the rock mass conditions of Kandiah valley.

关键词： Rock Mass Classification RMR and Q Deformation modulus (Em) Empirical Equations RocLab Tunnel

Vibration of Gold Nano-Beam with Variable Young’s modulus Due to Thermal Shock

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World Journal of Nano Science and Engineering 2015年第4期5卷 194-203页

作者： Eman A. N. Al-Lehaibi Hamdy M. Youssef Mathematics Department College of Science and Arts-Sharoura Najran University Najran KSA Mechanics Department Faculty of Engineering Umm Al-Qura University Makkah KSA

In this paper, we will study the most important effects in the nano-scale resonator: the coupling effect of temperature and strain rate, and the non-Fourier effect in heat conduction. A solution for the generalized thermoelastic vibration of nano-resonator induced by thermal loading has been developed. The Young’s modulus is taken as a linear function of the reference temperature. The effects of the thermal loading and the reference temperature in all the studied fields have been studied and represented in graphs with some comparisons. The Young’s modulus makes significant effects on all the studied fields where the values of the temperature, the vibration of the deflection, stress, displacement, strain, stress-strain energy increase when the Young’s modulus has taken to be variable.

关键词： Thermoelasticity Euler-Bernoulli Equation Goldnano-Beam Young’s modulus

Analysis of Fatigue Strain, Fatigue modulus and Fatigue Damage for the Model Formulation of Concrete Based on Strain Life Approach

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Engineering（科研） 2019年第9期11卷 642-674页

作者： Indra Narayan Yadav Kamal Bahadur Thapa Department of Civil Engineering Institute of Engineering Tribhuvan University Pulchowk Campus Lalitpur Nepal

Analysis of fatigue strain, fatigue modulus and fatigue damage for the modeling of concrete plays a vital role in the evolution material behaviour which is heterogeneous and anisotropic in nature. The Level-S nonlinear fatigue strain curve, fatigue modulus curve, residual strain curve of concrete in compression, tension, flexure and torsional fatigue loading were proposed using strain life approach. The parameters such as physical meaning, the ranges, and the impact on the shape of the curve were discussed. Then, the evolution model of fatigue modulus was established based on the fatigue strain, fatigue modulus, residual strain and secondary strain evolution model. The hypothesis of fatigue modulus is inversely related with the fatigue strain amplitude. The fatigue evolution of concrete damages the bond between material grains, changed the orientation of structure of molecules and affects the elastic properties resulting in the reduction of material stiffness and modulus by formation of microcracking, macro cracking, cracking and finally damage. This paper presents the fatigue strain life model and analysis of fatigue strain, fatigue modulus and damage parameters of concrete which is capable of predicting stiffness degradation, inelastic deformation, and strength reduction under fatigue loading and experimental results were employed for the validation of the theoretical model.

关键词： Fatigue Strain Life Approach Fatigue Strain Evolution Model Fatigue modulus Evolution Model Fatigue Residual Strain Evolution Model Fatigue Secondary Strain Stiffness

THE modulus OF CONVEXITY AND THE EQUIVALENT CONDITIONS OF UNIFORMLY NON-SQUARE SPACES

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Journal of Southeast University(English Edition) 1989年第1期6卷 15-20页

作者：韩瑞珠 Department of Mathematics and Mechanics

This paper shows that X is uniformly non-square iff P(η_o)>0 for someη_o∈(0,2).Thus X is super-reflexive if and only if for X there exists an equivalent normwhich meets the above condition.By virtue of the before mentioned result,the author derives the necessary,and suffi-cient conditions for X and l^p(X_j)being uniformly non-square,respectively,and gives acharacterization of finite-dimensional spaces which are uniformly non-square.

关键词： modulus convexity/uniformly non-square space super-reflexive space