The impact of a test method on the liquid limit of the selected cohesive soils

The research presented in this paper aimed at the determination of the impact of a test method on the liquid limit of the selected cohesive soils with diff erent content of clay fraction: loosely cohesive – clayey medium sand, moderately cohesive on the border of loosely cohesive – coarse silt and fi rmly cohesive – silty clay. Liquid limit was determined by the following methods: Casagrande, Vasiliev and the cone penetrometer. It was stated, that the values of the liquid limit of the tested soils determined by various methods were diff erent, which signifi cantly aff ected the assessment of their plasticity and consistency. According to the standard PKN-CEN ISO/TS 17892-2:2009, the liquid limit should be determined with the cone penetrometer, whereas the alternative is Casagrande’s method. The conducted tests showed, that in the case of cohesive soils containing up to 10–11% of clay fraction, the diff erences between the values of the liquid limit determined with the cone penetrometer and the Casagrande’s method were relatively small and equaled 1–2%, therefore both methods are correct. In the case of cohesive soils containing more than 20% of clay fraction, diff erences between the values of the liquid limit determined with the cone penetrometer and the Casagrande’s method were slightly higher than in the previous case, and equaled approximately 4%. In those cases, determination of the liquid limit can be performed both using the fi rst or the second method, though the above-cited standard recommends the cone penetrometer method.

A new Fokker-Planck approach for relaxation-driven evolution of galactic nuclei

We present an approach for simulating the collisional evolution of sphericalisotropic stellar systems based on the one-dimensional Fokker-Planck equation.A novel aspect is that we use the phase volume as the argument of thedistribution function, instead of the traditionally used energy, whichfacilitates the solution. The publicly available code, PhaseFlow, implements ahigh-accuracy finite-element method for the Fokker-Planck equation, and canhandle multiple-component systems, optionally with the central black hole andtaking into account loss-cone effects and star formation. We discuss the energybalance in the general setting, and in application to the Bahcall-Wolf cusparound a central black hole, for which we derive a perturbative solution. Westress that the cusp is not a steady-state structure, but rather evolves inamplitude while retaining an approximately $\rho\propto r^{-7/4}$ densityprofile. Finally, we apply the method to the nuclear star cluster of the MilkyWay, and illustrate a possible evolutionary scenario in which a two-componentsystem of lighter main-sequence stars and stellar-mass black holes develops aBahcall-Wolf cusp in the heavier component and a weaker $\rho\propto r^{-3/2}$cusp in the lighter, visible component, over the period of several Gyr. Thepresent-day density profile is consistent with the recently detected mild cuspinside the central parsec, and is weakly sensitive to initial conditions.

Lithofacies Reconstruction of the Lower-Middle Jurassic Sediments of the Yugansk Zone in Western Siberia

On the basis of litho-facial studies both lithofacies and depositional environments have been distinguished in the Lower-Middle Jurassic deposits of the Yugansk zone of the Western Siberia. Detailed analysis of core material showed that sedimentation occurred mainly in the conditions of alluvial plain in the extreme North-Western and Eastern parts of the territory turning to the upper delta plain occasionally flooded by the sea. High properties reservoirs are associated with facies point bars of straight channels, delta channels and сrevasse splays.

Lithogenetical Criteria of Reservoir Prediction in the Riphean Deposits of the Yurubcheno-Tokhomskoye Field, the East Siberia

On the basis of sedimentologycal, litho-petrographycal and facial studies both lithotypes, facies and depositional environments have been distinguished in the Riphean sedimentary sequences of the Yurubcheno-Tokhomskoye oil-gas field of the East Siberia. It has been established that the high property reservoirs relate to stromotolite buildups facies widely distributed in the Yurubchen, Kuyumbin and Dolgoktin Formations of the Upper Riphean.

Neutrino as Specific Magnetic ϒ-Quantum

In the present work, the consideration is being given to the possibility that neutrinos are specific magnetic γ-quanta (magnetic solitons), devoid electric components. It is shown that the creation of these magnetic γ-quanta in the empty space (in the ether) can be understood on the basis of standard Maxwell theory. As a rule, electrodynamics states that the electromagnetic waves are created by oscillations of dipoles. These waves have obligatorily electric and magnetic components. A magnetic γ-quantum radiates when a nuclear reaction creates a relativistic particle possessing a magnetic moment that the original particle does not have. Due to the lack of magnetic monopoles in nature, magnetic γ-quanta weakly interact with matter. This property allows to identify them with neutrinos. This concept finds confirmation in the fact that by following it we get a new insight into the nature of π-meson and μ-meson, and become able to calculate their masses with a good precision. It is supposed needed to repeat the Lederman’s experiment at low energy of neutrinos.

Black Holes or Dark Stars—What Follows from the General Relativity Theory

The paper is concerned with spherically symmetric static problem of the Classical Gravitation Theory (CGT) and the General Relativity Theory (GRT). First, the Dark Stars, i.e. the objects that are invisible because of high gravitation preventing the propagation of light discovered in the 18th century by J. Michel and P. Laplace are discussed. Second, the Schwarzchild solution which was obtained in the beginning of the 20th century for the internal and external spaces of the perfect fluid sphere is analyzed. This solution results in singular metric coefficients and provides the basis of the Black Holes. Third, the general metric form in spherical coordinates is introduced and the solution of GRT problem is obtained under the assumption that gravitation does not affect the sphere mass. The critical sphere radius similar to the Black Hole horizon of events is found. In contrast to the Schwarzchild solution, the radial metric coefficient for the sphere with the critical radius referred to as the Dark Star is not singular. For the sphere with radius which is less than the critical value, the GRT solution becomes imaginary. The problem is discussed within the framework of the phenomenological theory which does not take into account the actual microstructure of the gravitating objects and, though the term “star” is used, the analysis is concerned with a model fluid sphere rather than with a real astrophysical object.

Using parallel computing in modeling and optimization of mineral reserves extraction systems

Annotation . This article describes algorithm for solving ultimate pit limit problem (UPIT), or a maximum weight closure problem. There are several method for solving this problem. We provides new approach, forsolving ultimate pit limit problem using precedence model.Block model of open pit can be easily represented as an oriented graph. Then to solve ultimate pit limit problem it is required to find such a subgraph in a graph whose sum of weights will be maximal. One of the possible solutions of this problem is using genetic algorithms.We use a parallel genetic algorithm for accelerating of computational process. In this version of algorithm fitness function of each individual calculating in different thread. It allows reducing running time of algorithm.Details of implementation parallel genetic algorithm for searching open pit limitsare provided. Comparison with other methods and results of computational experiments provided.

Secondary positrons and electrons measured by PAMELA experiment

Technical Design Report for the Panda Forward Spectrometer Calorimeter

Theia: Faint objects in motion or the new astrometry frontier