scholarly journals Measurement of hydraulic conductivity under horizontal paths in granular soils

Respuestas ◽  
2019 ◽  
Vol 24 (3) ◽  
pp. 92-101
Author(s):  
Maria Fernanda García ◽  
Camilo Andres Aldana ◽  
Allex Fabrizio López ◽  
Juan Carlos Ruge C. ◽  
Eliana Martinez Rojas
Keyword(s):  
Hydraulic Conductivity ◽  
Permeability Coefficient ◽  
Point Of View ◽  
Granular Soils ◽  
Physical Point ◽  
Soil Layers ◽  
Coefficient Of Permeability ◽  
Geotechnical Structures ◽  
The Difference ◽  
Constant Head

In geotechnical structures, the permeability-dependent stability analysis is generally evaluated under vertical trajectories, because most permeameters are configured so that the water passes through the porous medium in this way. However, it is clear from the physical point of view that water can flow along different paths, including preferential ways that can include horizontal trajectories, parallel to the deposit of the stratum. The foregoing implies that both the vertical and horizontal component of the hydraulic conductivity or permeability coefficient must be estimated for a given stratum. The current research aims to explore possibilities for measuring the coefficient of permeability in horizontal trajectories, on granular soils, under a constant condition of relative density. For this purpose, a special chamber attached to a constant head permeameter was designed and constructed, which allows to measure the permeability in conditions of horizontal flow parallel to the soil layers. The proposed camera also admits the estimation of the permeability coefficient by combining stratifications of different granular soils, where the trajectories are not perfectly horizontal, but have diagonal paths. The results are compared with data obtained by conventional vertical flow permeameters, in order to check the difference in the measurements considering both situations in the samples. As a conclusion, it is important to report that there is evidently a difference in the permeability coefficients measured under different trajectories,

scholarly journals ANALISIS PERBANDINGAN NILAI KOEFISIEN PERMEABILITAS TANAH UJI LAPANGAN DAN UJI LABORATORIUM

2020 ◽  
Vol 3 (1) ◽  
pp. 97
Author(s):  
Philip Chen ◽  
Gregorius Sandjadja Sentosa
Keyword(s):  
Initial Data ◽  
Permeability Coefficient ◽  
Laboratory Tests ◽  
Pumping Test ◽  
Soil Permeability ◽  
Pumping Tests ◽  
Final Project ◽  
Coefficient Of Permeability ◽  
The Difference ◽  
Constant Head

The coefficient of permeability (k) results of pumping tests are used as initial data to determine the rate of water seepage in the soil, determining the permeability capability of the soil can be done by measurements in the laboratory and in the field. In reality the permeability coefficient value of field test is not the same as the test in the laboratory. This final project will analyze the difference in value (k) obtained from field and laboratory tests in order to enrich the data in determining the value of permeability coefficient (k). The analysis uses Thiem and Theis method in analyzing the results of pumping tests. And using constant head permeameter to determine the value of the coefficient of permeability (k) in laboratory. From the analysis results obtained by the Thiem method, the permeability coefficient (k) obtained is in the range of  6,8x cm/sec - 2,8x cm/sec, and Theis method is obtained in the range of  6,03x cm/sec - 6,03x cm/sec. Meanwhile the results of the coefficient of soil permeability (k) by the laboratory tests using the constant head permeameter is in the range 1,43x  cm/sec - 8,76x cm/sec. And for calculations using the Hazen method the result is in the range 8,71x cm/sec - 4,35x cm/sec.AbstrakNilai koefisien permeabilitas (k) hasil pumping test digunakan sebagai data awal untuk mengetahui kecepatan rembesan air di dalam tanah, penentuan kemampuan permeabilitas tanah dapat dilakukan dengan pengukuran di laboratorium dan di lapangan. Dalam kenyataannya nilai koefisien permeabilitas uji lapangan biasanya tidak sama dengan uji di laboratorium. Penelitian ini akan menganalisa perbedaan nilai (k) yang didapat dari uji lapangan dan uji laboratorium guna memperkaya data dalam menentukan nikai koefisien permeabilitas (k). Analisa pada penelitian ini menggunakan metode Thiem dan metode Theis dalam menganalisa hasil pumping test pada lapangan. Dan menggunakan constant head permeameter sebagai alat menentukan nilai koefisien permeabilitas (k) pada laboratorium. Serta menggunakan metode rumus empiris Hazen untuk menentukan nilai koefisien permeabilitas (k) berdasarkan ukuran butiran. Dari hasil analisis yang diperoleh dengan metode Thiem nilai koefisien permeabilitas (k) yang didapat berada pada rentang  6,8x m/detik - 2,8x cm/detik, dan dengan metode Theis didapat pada rentang 6,03x cm/detik - 6,03x cm/detik. Sedangkan hasil uji laboratorium menggunakan permeameter constant head mendapatkan hasil nilai koefisien permeabilitas tanah (k) pada rentang 1,43x  cm/detik  -   8,76x cm/detik. Dan didapat hasil 8,71x cm/detik - 4,35x cm/detik untuk perhitungan menggunakan metode Hazen.

scholarly journals Derivation of a New Equation to Obtain the Permeability Coefficient of Clayey Soils

2011 ◽  
Vol 5 (1) ◽  
pp. 20
Author(s):  
Maysm Th. Al-Hadidy
Keyword(s):  
Permeability Coefficient ◽  
Clayey Soil ◽  
Point Of View ◽  
Clayey Soils ◽  
Coefficient Of Permeability ◽  
Long Time ◽  
Consolidation Rate ◽  
Degree Of Consolidation ◽  
New Equation ◽  
Short Time

The main objective of this research is to find the coefficient of permeability (k) of the soil and especially clayey soil by finding the degree of consolidation (rate of consolidation). New modify procedure is proposed by using the odometer (consolidation) device. The ordinary conventional permeability test usually takes a long time by preparing and by testing and this could cause some problems especially if there is a need to do a large number of this test and there were a limited number of technicians and/or apparatus. From this point of view the importance of this research is clear, since the modified procedure will require a time of 25 minute only. Derivation made to produce an equation which could be used to fined the permeability if the proposed procedure fallowed to find the permeability of soils and this done by specification the degree of consolidation at any loading stage. The results of permeability found by the proposed procedure and by ordinary test (directly by falling head method, and indirectly by accelerated consolidation method using the oedometer device). After that these results were found by proposed procedure compared with that results which found by ordinary test. it has been found that this equation give a very good results with (95.83) % accuracy and degree of correlation of (0.9988) comparing with ordinary methods and beside that it takes a very short time.

scholarly journals NAM–SCA: A Nonhydrostatic Anelastic Model with Segmentally Constant Approximations

2010 ◽  
Vol 138 (5) ◽  
pp. 1957-1974 ◽  
Author(s):  
Jun-Ichi Yano ◽  
Pierre Bénard ◽  
Fleur Couvreux ◽  
Alain Lahellec
Keyword(s):  
Point Of View ◽  
Prototype Model ◽  
Convective System ◽  
Convective Boundary ◽  
Physical Point ◽  
The Difference ◽  
Modeling Strategy ◽  
The Given ◽  
Number Of Segments ◽  
Vertical Level

Abstract An atmospheric convective system may be modeled as an ensemble of discrete plume elements. A representation of decomposited plumes provides the basis for mass-flux convective parameterization. A dry version of such a prototype model is constructed in a two-dimensional horizontally periodic domain. Each discrete plume element is approximated by a horizontally homogeneous segment such that the whole system is given by segmentally constant approximations (SCA) in the horizontal direction for each vertical level in a nonhydrostatic anelastic model (NAM). The distribution of constant segments is highly inhomogeneous in space and evolves with time in a highly adaptive manner. The basic modeling strategy from a physical point of view is to activate new segments vertically upward with time when a convective plume is growing and to deactivate segments when a plume event is over. The difference in physical values crossing segment interfaces is used as a criterion for numerically implementing this strategy. Whenever a large difference is found, the given interface is stretched vertically by subdividing an existing segment into two. In turn, when a segment interface difference is found below the threshold, the given interface is removed, thereby merging the two segments into one. This nonhydrostatic anelastic model with segmentally constant approximations (NAM–SCA) is tested on an idealized atmospheric convective boundary layer. It successfully simulates the evolution of convective plumes with a relatively limited number of segments (i.e., high compression) and with a much scarcer distribution of segments over nonplume environments (i.e., extremely inhomogeneous distribution of segments). Overall, this method compresses the size of the model up to 5 times compared to a standard NAM with homogeneous grid distribution without substantially sacrificing numerical accuracy.

Granular soils in rigid-wall permeameters: method for determining the degree of saturation

1989 ◽  
Vol 26 (1) ◽  
pp. 71-79 ◽  
Author(s):  
Robert P. Chapuis ◽  
Karsten Baass ◽  
Luc Davenne
Keyword(s):  
Hydraulic Conductivity ◽  
Test Procedure ◽  
Rigid Wall ◽  
Standard Test ◽  
Test Method ◽  
Degree Of Saturation ◽  
Granular Soils ◽  
Test Results ◽  
Constant Head

The standard test method used to determine the hydraulic conductivity of a clean granular soil (rigid-wall permeameter –constant head difference) requires that the specimen be saturated with an air-vacuum pump. However, no method is provided to verify whether the sample is fully (100%) saturated. This paper proposes such a method and establishes its accuracy. The method allows for quality control of the rigid-wall permeameter itself: it can detect if it is watertight but not airtight, according to the achieved degree of saturation. A detailed example is given on a proposed data sheet. The reasons for partial saturation and the problems related to air bubbles are examined. The result of this examination is a simplified test to check a permeameter, based on the fact that for unsaturated conditions the hydraulic conductivity depends on which of two ways the water seeps in a given direction. A few modifications in the preparation of the specimen and the test procedure are suggested so as to improve the quality of test results. Key words: permeability, laboratory, granular soils, rigid-wall permeameter, saturation.

Pleasure as a Sign of Efficacy of Mental Activity

1997 ◽  
Vol 2 (3) ◽  
pp. 226-234 ◽  
Author(s):  
Michel Cabanac ◽  
Chantal Pouliot ◽  
James Everett
Keyword(s):  
Evolutionary Psychology ◽  
Magnitude Estimation ◽  
Mental Activity ◽  
Point Of View ◽  
Macintosh Computer ◽  
Science Students ◽  
Cognitive Efficiency ◽  
Sensory Pleasure ◽  
The Difference ◽  
Mental Tasks

Previous work has shown that sensory pleasure is both the motor and the sign of optimal behaviors aimed at physiological ends. From an evolutionary psychology point of view it may be postulated that mental pleasure evolved from sensory pleasure. Accordingly, the present work tested empirically the hypothesis that pleasure signals efficacious mental activity. In Experiment 1, ten subjects played video-golf on a Macintosh computer. After each hole they were invited to rate their pleasure or displeasure on a magnitude estimation scale. Their ratings of pleasure correlated negatively with the difference par minus performance, i.e., the better the performance the greater the pleasure reported. In Experiments 2 and 3, the pleasure of reading poems was correlated with comprehension, both rated by two groups of subjects, science students and arts students. In the majority of science students pleasure was significantly correlated with comprehension. Only one arts student showed this relationship; this result suggests that the proposed relationship between pleasure and cognitive efficiency is not tautological. Globally, the results support the hypothesis that pleasure is aroused by the same mechanisms, and follows the same laws, in physiological and cognitive mental tasks and also leads to the optimization of performance.

COMBINATORIAL POLYNOMIALLY COMPUTABLE CHARACTERISTICS OF SUBSTITUTIONS AND THEIR PROPERTIES

2020 ◽  
Vol 7 (2) ◽  
pp. 34-41
Author(s):  
VLADIMIR NIKONOV ◽  
◽  
ANTON ZOBOV ◽  
Keyword(s):  
Mathematical Expectation ◽  
Point Of View ◽  
Small Range ◽  
Computational Point ◽  
Wide Range ◽  
Bijective Function ◽  
The Difference ◽  
Element Base ◽  
Selection Of

The construction and selection of a suitable bijective function, that is, substitution, is now becoming an important applied task, particularly for building block encryption systems. Many articles have suggested using different approaches to determining the quality of substitution, but most of them are highly computationally complex. The solution of this problem will significantly expand the range of methods for constructing and analyzing scheme in information protection systems. The purpose of research is to find easily measurable characteristics of substitutions, allowing to evaluate their quality, and also measures of the proximity of a particular substitutions to a random one, or its distance from it. For this purpose, several characteristics were proposed in this work: difference and polynomial, and their mathematical expectation was found, as well as variance for the difference characteristic. This allows us to make a conclusion about its quality by comparing the result of calculating the characteristic for a particular substitution with the calculated mathematical expectation. From a computational point of view, the thesises of the article are of exceptional interest due to the simplicity of the algorithm for quantifying the quality of bijective function substitutions. By its nature, the operation of calculating the difference characteristic carries out a simple summation of integer terms in a fixed and small range. Such an operation, both in the modern and in the prospective element base, is embedded in the logic of a wide range of functional elements, especially when implementing computational actions in the optical range, or on other carriers related to the field of nanotechnology.

TO THE PROBLEMS OF COMBATING CORRUPTION IN MODERN RUSSIA AND INTERNATIONAL COOPERATION IN THE FIELD OF ANTI-CORRUPTION

2020 ◽  
Author(s):  
Angela Dranishnikova
Keyword(s):  
Large Scale ◽  
The State ◽  
Point Of View ◽  
Modern Life ◽  
Existing Problems ◽  
Moral Point ◽  
Material Goods ◽  
The Russian Federation ◽  
The Difference ◽  
The Government

In the article, the author reflects the existing problems of the fight against corruption in the Russian Federation. He focuses on the opacity of the work of state bodies, leading to an increase in bribery and corruption. The topic we have chosen is socially exciting in our days, since its significance is growing on a large scale at all levels of the investigated aspect of our modern life. Democratic institutions are being jeopardized, the difference in the position of social strata of society in society’s access to material goods is growing, and the state of society is suffering from the moral point of view, citizens are losing confidence in the government, and in the top officials of the state.

ЕКАТЕРИНА ВЕЛИКАЯ И ДИАЛЕКТИКА ПРОСВЕЩЕННОЙ МОНАРХИИ

2020 ◽  
Vol 15 (1) ◽  
pp. 39
Author(s):  
С. И. Дудник ◽  
И. Д. Осипов
Keyword(s):  
Cultural Policy ◽  
Separation Of Powers ◽  
Point Of View ◽  
Human Sciences ◽  
The Rule Of Law ◽  
Political Ideas ◽  
The People ◽  
Specific Interpretation ◽  
The Difference ◽  
Conservative Values

The article discusses the problems of evolution and the formation of the ideology of an enlightened monarchy in Russia. In this regard, the philosophical and political ideas of Catherine the Great, as well as their theoretical and ideological premises, are analyzed. It is noted that the philosophy of education in Russia was closely connected with the concepts of Voltaire, Didro, Montesquieu, Beccaria, Bentham, their views on natural law and human freedom, humanism and the rule of law. These concepts in the philosophy of Catherine received a specific interpretation, due to the sociocultural conditions of Russia. This was manifested in the famous work of Catherine the Great “The Nakaz”, which recognized Montesquieu's argument in favor of the autocracy, but at the same time, his point of view on the separation of powers was rejected. The specificity of the doctrine of enlightened monarchy lies in the combination of liberal and conservative values, which form eclectic forms. This was the dialectic of the supreme power, the difference between the enlightened monarchy and the ideology of absolutism. The article also notes that education in Russia is associated with fundamental socio-political reforms, processes of secularization of culture. At this time, the natural and human sciences are developing. The changes positively influenced the development of medicine, beautification of towns and public education. Also considered are the views on the autocracy of the opposition nobility intelligentsia: A. N. Radishchev and noted that his criticism of the autocracy was determined by an alternative cultural policy, proceeding from the protection of the interests of the people. The doctrine of enlightened monarchy is characterized by internal worldview inconsistency and political inconsistency, which did not allow solving the pressing social problems of the establishment of legal state, democratization of society and the abolition of serfdom.

GROUNDWATER TIME SERIES

1970 ◽  
Vol 1 (3) ◽  
pp. 181-205 ◽  
Author(s):  
ERIK ERIKSSON
Keyword(s):  
Time Series ◽  
Point Of View ◽  
Hydrologic Models ◽  
Physical Point ◽  
Run Off ◽  
Fort Collins ◽  
Statistical Sense ◽  
Full Benefit ◽  
Future Work ◽  
Prediction Problems

The term “stochastic hydrology” implies a statistical approach to hydrologic problems as opposed to classic hydrology which can be considered deterministic in its approach. During the International Hydrology Symposium, held 6-8 September 1967 at Fort Collins, a number of hydrology papers were presented consisting to a large extent of studies on long records of hydrological elements such as river run-off, these being treated as time series in the statistical sense. This approach is, no doubt, of importance for future work especially in relation to prediction problems, and there seems to be no fundamental difficulty for introducing the stochastic concepts into various hydrologic models. There is, however, some developmental work required – not to speak of educational in respect to hydrologists – before the full benefit of the technique is obtained. The present paper is to some extent an exercise in the statistical study of hydrological time series – far from complete – and to some extent an effort to interpret certain features of such time series from a physical point of view. The material used is 30 years of groundwater level observations in an esker south of Uppsala, the observations being discussed recently by Hallgren & Sands-borg (1968).

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