This paper outlines a mathematical description of the stress dilatancy behaviour of granular materials which accounts for stress level and void ratio dependencies. The consideration of these aspects has important implications in the modelling of granular material behaviour. In fact, granular material mechanical response is largely dominated by the evolution of dilatancy, fabric and void ratio histories. The starting point in this study is the well established Rowe's theory which is revisited and ultimately modified by introducing a factor linked to governing state parameters in order to describe the complete behaviour of granular materials during deformation. Numerical simulations of triaxial tests on granular materials at different void ratios and stress levels are herein presented to illustrate the model.

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The main objective of this paper is to compare safety factors obtained from Morgenstern-Price, Janbu and Spencer methods with the factors calculated from the modified variational approach (Leshchinsky and Huang, 1992a). Such comparison is essential since there is no mathematical proof that the variational analysis indeed yields a minimum and thus, physically produce significant results. The safety factors compared well, indicating the variational analysis is on a par with acceptable existing rigorous methods. Availability of a user-friendly computer code may make the variational analysis useful to practicing engineers. However, its greatest potential at the moment is in 3-D applications; i.., unlike other methods, its extension to 3-D is straightforward.

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The design implication of stress-confinement effect of nonwoven geotextile is addressed. The unconfined and confined strengths of a selected needle-punched nonwoven geotextile are used to conduct a comparative design of a granular soil retaining wall based on a limit equilibrium approach. A higher wall may be allowed when considering the confined strength as compared to the unconfined strength. For a selected wall height, confined strength allows for fewer geotextile layers when compared to that designed using unconfined strength. It is recommended that stress-confinement test procedure should be standardized so that confinement effect of some nonwoven geotextiles may be incorporated into an individual wall design procedure.

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Circuit techniques to enhance the linearity of input-voltage-to-current (V/I) conversion and to increase the output impedance of a current source by compensating for the low intrinsic gain of a transistor were introduced to realize a high-frequency operational transconductance amplifier (OTA) for a low supply voltage using sub-100-nm CMOS processes. Applying these techniques, a MOS 7th-order Gm- linear-phase low-pass filter (LPF) was realized using a 65nm CMOS process. A simplified biquad LPF that can serve as a component of a 7th-order LPF was newly developed by replacing OTAs with resistors. As a result, the -3dB frequency bandwidth, group delay ripple, 3rd-order distortion, and 3rd-order input intercept point (IIP3) were 200MHz, 2.2%, ≤ -55dB with a 100MHz input, and +10.3dBm, respectively, all with a ±.Vp-p input signal at each input terminal in the pseudodifferential configuration. The LPF including an output buffer dissipated 60mW in the case of a .2V supply. Wide spurious-free dynamic range (SFDR) characteristics were confirmed up to high frequencies.

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[] The purpose of this reserch is to make clear what type of design can give good effects to win the high readership score. At the begining I had to know what factors decide the readership score, and how to change the quality of the desing into numerical value. I have used the method of multi-dimentional analysis with the help of a computer, and got the estimation formula, with 7 kinds of factors, as follows ; A^^〜=B++D+K+aE++cG. A^^〜=estimated values of the readership score. ) B, , D, K : these four factors are given as category values (so we call them); each factor is classified into several categories. B=week day, classified into 7 categories. =pages of a newspaper, which are characterized by the kinds of articles, news, and the other reading matters, classified into categories. D=kinds of goods and trades of the advertizement, classified into 14 catedories. K=constants, given to each 13 surveys. 2) , F, G : these factors are given as numerical values. G=area of advertizement, measured by the unit of column in the whole page length, being classified into kinds of area (2., 3., , 7, 10, 15) and 15 column means a whole page, about 2,000cm^2. , F are the marks obtained in the design of advertizements. =sum of the marks obtained in each design element on the advertizement. F=the marks obtained on the whole effect of the design. 3) a, b, : coefficients Using the above formula with the category values and the coefficients, we can obtain the naked design effect from the actual value A of readership score: aE+=A-(B++D+K+cG). In this research, I used ,829 data of readership score from 1960 to 1968, being obtained by 13 survevs, spring and autumn twice a year. The sample of size each survey was 3,541, 2,251, or 200 in the other 11 surveys. Multiple correlation coefficient between the estimated value A^^〜 and the actual value A is .951. The table 2^* shows the contribution indexes of each factor by 3 kinds of expression-() Range : the absolute difference between the maximum and the minimum category values, (2) Standard deviations of the category values, (3) Partial correlation coefficient : the relationship between the actual values A and each factors. *see the table 2 in the thesis in Japanese. [2] The important point was in the determination of the values of , F. is the sum of the marks obtained in each design element, classified into four kinds : =_+_2+_3+_. design elements [table] _, _2, _3, _, these values have the grades, as , , 2, 3, and is given to the design that has no attractive effect or no applicable element. And obtain the marks of to grades as the sum of them. The values of F have also grades, to . The principles to determine the values of , F are as follows : a) The marks obtained of , F must be the relative values among the each survey, and at the same time, they must have constancy within the same survey-the same elements of design must win the same marks obtained. b) They must be determined as to win the highest multiple correlation coefficient, when they are put into the estimation formula. ) They must be reasonable. In order to justify them, we must carry many researches on the actual condition. The frequency of accurence of each grade of , F values, as the table -, and - in the thesis in Japanese.

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It has been shown after mathematical and mechanical investigation that Limit Equilibrium Method (LEM) can be considered as a method to obtain the necessary condition of Slip Line Method (SLM), and that the solution can be obtained under the condition that F_s= and ∂F_s/∂θ=O, where F_s is the safety factor and θ is the inclination of the plane on which the safety factor is defined. Next, the generalized LEM (GLEM) is proposed, dealing with the following points : () Triangular or quadrangular blocks can be treated; (2) Safety factors are defined also on interblock planes; and (3) All types of plastic problems, slope stability, bearing capacity, and earth pressure are identically formulated. Two situations regarding treatment of the moment equilibrium condition are discussed. GLEM is applied to well-known problems. The results agree well with those obtained by theoretical methods. GLEM can be used to obtain the distribution of earth pressure or bearing capacity. GLEM, Iike ordinary LEM, is very effective for the practical problems, but GLEM is more theoretical and it can result in more accurate solutions.

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A procedure for limit equilibrium slope analysis based on a realistic consideration of the mobilized interslice shear forces is presented in this paper. This new approach ensures that solutions are kinematically admissible and the possibility of convergence problems, often associated with numerical solutions, is minimized. The proposed approach recognizes the importance of slip surface geometry in estimating interslice shear forces whether vertical or non-vertical slices are used in a limit equilibrium analysis. Illustrative examples are presented and the results shown to be reasonable. The calculated factors of safety based on the new method compare very well with values based on recognized methods of analysis. Yet the method is more direct and enables a proper visualization of the transfer of mobilized normal and shear forces through a sloping soil mass above a potential slip surface. The method also gives consistent results with non-vertical slices even if the shape of non-vertical slices is varied.

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The small strain stiffness and anisotropic nature of two sands with different geological origin have been determined via laboratory seismic tests performed in a triaxial cell. Dry triaxial reconstituted specimens of Ticino river silica sand (TS) and of Kenya carbonatic sand (KS) were subjected to isotropic and anisotropic states of effective stress ; then both shear and constrained compression waves were propagated in vertical, horizontal and oblique directions by means of five couples of piezoelectric transducers especially arranged in the specimens. The propagated compression and shear waves allow the assessment of the constrained and shear moduli respectively, at very small strains where, as a first approximation many soils can be assumed, from an engineering point of view, to behave as an elastic cross-anisotropic medium with a vertical axis of symmetry. This paper, after a brief description of the novel measuring technique adopted and of the tested materials, summarises the test results and their interpretation in order to separate the effects of the fabric anisotropy from those produced by the state of effective stresses on soil stiffness. The stiffness and anisotropic response of the two tested sands are compared. Finally the results enable us to establish five independent constants of the cross-anisotropic elasticity model, which appears to be appropriate to reproduce the behaviour at small strain of the two sands.

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Repetitive liquefactions in angular and subangular gravels from an alluvial fan, in the case of two earthquakes with accelerations lower than that of a former which had caused liquefaction some months before, are described. The liquefaction took place from the surface, down to a depth of approximately 10 m. Water laden with sediments spouted out for some tens of minutes after the strong motion ceased. Knowledge of the grain size distribution of the sediments inside the body of the alluvial fan roughly defines the areas of the fan prone to future liquefaction. Non-repetitive liquefaction in overconsolidated fine fluvio-lacustrine sand of glacial origin at the unusual depth of 14 m to 16 m is also described. From the observation of sand lifted up for 10 m inside a large diameter well, and of that which spouted out from several microvents, it was estimated that extra-pore pressure was close to lithostatic conditions. Nevertheless, modeling of intrinsic pore pressure buildup on the DESRA2 programme gives lower values than the experimental one. Geotechnical characteristics of the 12 m-thick sandy stratum indicate that the upper part is unusually soft, either due to water circulation or past repetitive liquefactions which prevented reconsolidation. It is suggested that excess pore pressure generated by the earthquake was also due to redistribution of pressure from adjacent sediments.

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A new analytical method is proposed for determining the inextensible grid reinforcement pullout resistance and pullout force/pullout displacement curve by using basic backfill soil and grid reinforcement properties. The pullout skin friction resistance/pullout displacement relationship is simulated by linear elastic-perfectly plastic model. A hyperbolic model has been proposed to represent the pullout bearing resistance/pullout displacement relationship in which the maximum bearing resistance of a single bearing member is determined using a new bearing capacity equation proposed in this paper. The influences of the grid bearing member spacing ratio, S/D, the bearing member deflection rigidity, and the pullout softening behavior on the mobilization of pullout bearing resistance are explicitly included in the proposed model. Good agreement has been obtained between calculated values and laboratory test results.

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A monoclonal antibody, established from mice injected with dolphin peripheral blood lymphocytes (PBLs) was characterized. In addition to its reactivity against 89.% of dolphin PBLs, reacted with 33.% of bovine PBLs of which % were CD ⁺, 11.% were -. recognized a 34 kD protein on the surface of dolphin and bovine PBLs. Analysis of the protein's N-terminal amino acid sequence indicated that recognizes bovine major histocompatibility complex (MHC) class II antigens. These results suggested that recognized MHC class II antigens on bovine PBLs. As we have already produced an anti-dolphin MHC class I monoclonal antibody, analysis of immune system using these monoclonal antibodies will advance our understanding of the evolution of the mammalian immune system.

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