scholarly journals Probabilistic assessment of the role of the soil degradation main factors in Kuban rice fields

2020 ◽  
Vol 175 ◽  
pp. 09011
Author(s):  
Tatyana Safronova ◽  
Stanislav Vladimirov ◽  
Igor Prikhodko
Keyword(s):  
Soil Quality ◽  
Colloidal Particles ◽  
Irrigation System ◽  
Probability Distributions ◽  
Soil Formation ◽  
Soil Condition ◽  
Point Of View ◽  
Secondary Salinization ◽  
Average Value ◽  
Operational Activities

As a result of reclamation systems for rice cultivation construction, the conditions of genesis and landscapes soil formation were radically violated. This led to the leaching of active humus and calcium, colloidal particles, nutrients from arable layer to underlying horizons, as a result of which there is a tendency to secondary salinization and solonization of soils. The development of the eluvial glue process and physicochemical parameters change of soils causes a change in the morphological soil profile. Currently relevant are preventing land degradation problems, maintaining and restoring soil fertility. In the article, the authors propose to characterize the rice irrigation system functioning mode from probabilistic point of view. They offer to evaluate the consequences of anthropogenic load, considering operational activities by Poisson stream of a certain intensity. This approach allows to consider uncertainty in terms of probability distributions. The function, characterizing soil quality S(t) was introduced. The function S(t) assumed to be monotonously decreasing. The probability R(S) of achieving a certain soil quality was considered. In case of minimum amount of humus Sm the soil is degrading. In these assumptions the average value expression and probability density of particular soil condition onset duration was received.

Localized Irrigation System for Thuja Orientalis in Intensive Culture

2018 ◽  
Vol 20 (1) ◽  
pp. 119-126
Author(s):  
Mădălina Stănescu ◽  
Constantin Buta ◽  
Geanina Mihai ◽  
Lucica Roșu
Keyword(s):  
Irrigation System ◽  
Ornamental Plants ◽  
Point Of View ◽  
First Year ◽  
Intensive Culture ◽  
Technical Point ◽  
Production Factors ◽  
Thuja Orientalis ◽  
Agricultural Farm

Abstract In order to increase the competitiveness of an agricultural holding through the efficient use of the production factors, the modernization of an agricultural farm was carried out by exending the existing greenhouse with at least 700m2 for the intensive cultivation of ornamental plants - Thuja Orientalis. The material is produced by initiating crops in pots, with seedlings grown in pots or transplanting them in pots right after the first year of the multiplication and growing them in containers, appropriate to their size, until reaching their full value. From a technical point of view, reaching the objective will also be possible through a localized irrigation system.

scholarly journals Modeling and theoretical description of magnetic hybrid materials—bridging from meso- to macro-scales

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Andreas M. Menzel ◽  
Hartmut Löwen
Keyword(s):  
Colloidal Particles ◽  
Colloidal Particle ◽  
Theoretical Description ◽  
Point Of View ◽  
Material Behavior ◽  
Theoretical Point ◽  
Mechanical Stiffness ◽  
Theoretical Approaches ◽  
Theoretical Predictions ◽  
Particle Level

Abstract Magnetic gels and elastomers consist of magnetic or magnetizable colloidal particles embedded in an elastic polymeric matrix. Outstanding properties of these materials comprise reversible changes in their mechanical stiffness or magnetostrictive distortions under the influence of external magnetic fields. To understand such types of overall material behavior from a theoretical point of view, it is essential to characterize the substances starting from the discrete colloidal particle level. It turns out that the macroscopic material response depends sensitively on the mesoscopic particle arrangement. We have utilized and developed several theoretical approaches to this end, allowing us both to reproduce experimental observations and to make theoretical predictions. Our hope is that both these paths help to further stimulate the interest in these fascinating materials.

scholarly journals A Brief Review of Generalized Entropies

Entropy ◽  
2018 ◽  
Vol 20 (11) ◽  
pp. 813 ◽  
Author(s):  
José Amigó ◽  
Sámuel Balogh ◽  
Sergio Hernández
Keyword(s):  
Diffusion Processes ◽  
Complex Dynamics ◽  
Probability Distributions ◽  
Point Of View ◽  
Scaling Exponent ◽  
Scaling Exponents ◽  
Physical Systems ◽  
New Phenomena ◽  
Generalized Entropies

Entropy appears in many contexts (thermodynamics, statistical mechanics, information theory, measure-preserving dynamical systems, topological dynamics, etc.) as a measure of different properties (energy that cannot produce work, disorder, uncertainty, randomness, complexity, etc.). In this review, we focus on the so-called generalized entropies, which from a mathematical point of view are nonnegative functions defined on probability distributions that satisfy the first three Shannon–Khinchin axioms: continuity, maximality and expansibility. While these three axioms are expected to be satisfied by all macroscopic physical systems, the fourth axiom (separability or strong additivity) is in general violated by non-ergodic systems with long range forces, this having been the main reason for exploring weaker axiomatic settings. Currently, non-additive generalized entropies are being used also to study new phenomena in complex dynamics (multifractality), quantum systems (entanglement), soft sciences, and more. Besides going through the axiomatic framework, we review the characterization of generalized entropies via two scaling exponents introduced by Hanel and Thurner. In turn, the first of these exponents is related to the diffusion scaling exponent of diffusion processes, as we also discuss. Applications are addressed as the description of the main generalized entropies advances.

scholarly journals PENERAPAN MODEL PEMBELAJARAN KOOPERATIF JIGSAW UNTUK MENINGKATKAN MOTIVASI PADA SISWA KELAS V SEKOLAH DASAR

2020 ◽  
Vol 7 (2) ◽  
pp. 56-63
Author(s):  
Bandi Usman ◽  
Khairil Akbar ◽  
Kurnia Dyah Anggorowati
Keyword(s):  
Physical Education ◽  
Student Learning ◽  
Learning Model ◽  
Point Of View ◽  
Learning Motivation ◽  
Fifth Grade ◽  
Motivation To Learn ◽  
Average Value ◽  
Fifth Grade Students ◽  
Using Data

Abstrak: This study aims to increase student learning motivation in the field of physical education, sports and health. The learning model used is the application of the learning model through cooperative jigsaw to increase learning motivation in the field of physical education, sports and healthfor fifth grade students. Classroom action research (PTK) is carriedout using data collection techniques, namely motivation tests and questionnaires. The results of this study showed that in cycle 1, the average value of student learning motivation was 73% in the motivated category but not yet complete. Then in cycle II obtained a percentage of learning motivation of 90% categorized as motivated according to the success criteria and seen from the point of view of the maximum completeness criteria (KKM) students are said to be complete. The percentage of increasing learning motivation from cycle I to cycle II was 17%. The jigsaw cooperative learning model can increase student motivation, especially in sports and health physical education subjects.Keywords: learning Model, motivation to learn physical education sports and health.Abstrak: Penelitian ini bertujuan untuk meningkatkan motivasi belajar siswa pada bidang studi Pendidikan Jasmani Olahraga dan Kesehatan. Model pembelajaran yang digunakan adalah penerapan model pembelajaran melalui kooperatif Jigsaw untuk meningkatkan motivasi belajar pada bidang studi Pendidikan Jasmani Olahraga dan Kesehatan pada siswa kelas V, dilakukan penelitian tindakan kelas (PTK) dengan teknik pengumpulan data yakni tes dan angket motivasi. Hasil penelitian ini diperoleh siklus I nilai rata-rata motivasi belajar siswa presentase sebesar 73% kategori termotivasi tetapi belum tuntas. Kemudian pada siklus II diperoleh presentase motivasi belajar sebesar 90% dikategorikan termotivasi sesuai kriteria keberhasilan dan dilihat dari sudut pandang kriteria ketuntasan maksimal (KKM) siswa sudah dikatakan tuntas. Presentase peningkatan motivasi belajar siklus I ke siklus II yaitu 17%. Model pembelajaran kooperatif jigsaw dapat meningkatkan motivasi belajar siswa, terutama pada mata pelajaran Pendidikan Jasmani Olahraga dan Kesehatan.Kata Kunci: Model Pembelajaran, Motivasi Belajar Pendidikan Jasmani Olahraga dan Kesehatan

scholarly journals MECHANICAL STRENGTH OF COAL: METHODS OF DETERMINATION AND FACTORS OF INFLUENCE (REVIEW)

2021 ◽  
Vol 6 ◽  
pp. 4-17
Author(s):  
V.V Koval ◽  
D.V. Miroshnichenko ◽  
O.V. Bogoyavlenska
Keyword(s):  
Mechanical Strength ◽  
Physical Properties ◽  
Physical And Mechanical Properties ◽  
Mechanical Tests ◽  
Point Of View ◽  
Statistical Characteristics ◽  
Measuring Instruments ◽  
Industrial Processing ◽  
Average Value ◽  
Advantages And Disadvantages

The article substantiates the importance and problems of determining of such an indicator of the quality of solid fossil fuels, as mechanical strength. The strength of coal depends on a large number of factors (viscosity, brittleness, properties of structural bonds, etc.), the change of which is impossible to take into account. Therefore, the strength of coal in the sample, piece, pack and formation must be represented by some integral index, which inevitably fluctuates around a certain average value and can be determined only approximately. The evaluation of the strength properties of coal should be carried out on the basis of mass tests using statistical methods that allow to calculate the average value and coefficient of variation. Since the strength dispersion is mainly due to the natural inhomogeneity of the coal, the excessive accuracy of the measuring instruments has almost no effect on the statistical characteristics. Laboratory methods of mechanical tests of mine samples, in comparison with full-scale, as a rule, are very accessible and, at qualitative performance of tests, are highly reliable. The properties of coal as an object of enrichment and use are largely related to its physical properties. The physical properties of coal and mineral impurities significantly affect the formation of the main parameters that characterize the particle size distribution and fractional composition, it`s changes during the mining, transportation and enrichment processes. The basic physical and mechanical properties of solid fuels from the point of view of their industrial processing have been listed, the review has been made of the most widespread methods of study of coals mechanical durability and the equipment used for these purposes. The main advantages and disadvantages have been summarized of these methods, as well as their relationship. The factors have been Indicated tinfluencing the mechanical strength of coal. The expediency of using existing methods from the point of view of informativeness for thesphere of its application has been estimated. The methods common in the coal processing industry are considered in more detail. Keywords: coal, solid fuel mining, mechanical strength, determination methods, influencing factors, grinding strength, crushing index. Corresponding author V.V. Koval, e-mail: [email protected]

Soils

2019 ◽  
pp. 67-90
Author(s):  
Nicola P. Randall ◽  
Barbara Smith
Keyword(s):  
Soil Erosion ◽  
Soil Quality ◽  
Agricultural Practices ◽  
Soil Formation ◽  
Soil Biology ◽  
Soil Processes ◽  
Soil Biodiversity ◽  
Productive Land ◽  
And Function ◽  
Agriculture And Food

This chapter gives a basic introduction to soil formation and fundamental soil processes in agroecosystems. The types of soils found in agroecosystems and their importance for agriculture is explored, with a principal focus on soil biodiversity, i.e. soil-dwelling organisms, their variety and function, and the interaction between soil biology, agriculture, and food production. The chapter describes some of the issues associated with soils in agroecosystems. These include interactions between agricultural practices and soil erosion and soil quality issues such as salinization and desertification. The major challenges to maintaining ‘healthy’ soils on productive land are outlined, and approaches and techniques for managing soils described.

Soil quality — soil condition — production stability

2006 ◽  
Vol 34 (1) ◽  
pp. 135-138 ◽  
Author(s):  
Márta Birkás ◽  
Anthony Dexter ◽  
Tibor Kalmár ◽  
László Bottlik
Keyword(s):  
Soil Quality ◽  
Soil Condition

Comparison of reduction efficiency of woven straw for entrained emissions of particulate matter with diameters less than 10 µm (PM10) and less than 2.5 µm (PM2.5) from exposed areas at construction sitesA paper submitted to the Journal of Environmental Engineering and Science.

2010 ◽  
Vol 37 (5) ◽  
pp. 787-795 ◽  
Author(s):  
Kuo-Tung Su ◽  
Yu-Min Chang ◽  
Wei-Hsing Hu ◽  
Shiao-Shing Chen ◽  
Chao-Hsiung Wu ◽  
...  
Keyword(s):  
Particulate Matter ◽  
Engineering Application ◽  
Point Of View ◽  
Construction Sites ◽  
Coverage Ratio ◽  
Average Value ◽  
Wind Speeds ◽  
Particulate Matter Emissions ◽  
Approach Zero ◽  
Tunnel System

From an engineering application point of view in reducing fugitive particulate matter emissions, this paper presents experimental data comparing the efficiency of woven straw at reducing entrained emissions of particulate matter with diameters less than 10 µm (PM10) with that for particulate matter with diameters less than 2.5 µm (PM2.5) at construction sites. A series of field-analogous experiments were carried out to continuously measure PM10 and PM2.5 using laser particle monitors in an artificial wind tunnel system. It was found that the efficiency of woven straw at reducing either PM10 or PM2.5 is significantly dependent on the woven straw coverage ratio. The maximum reduction efficiencies for PM10 and PM2.5 are about 40% and 12%, respectively. Note that the reduction efficiencies approach zero as the coverage ratio is less than about 40%. Total elimination of PM2.5 and PM10 emissions is not possible, even using full-coverage woven straw. Reduction of PM2.5 emissions is less efficient than that of PM10 emissions using woven straw, and this trend is likely more obvious with an increase in the woven straw coverage ratio. The ratio of reduction efficiencies (R) between PM2.5 and PM10 for woven straw decreased slightly with an increase in the woven straw coverage ratio. Overall, for wind speeds of 0.5–3.0 m/s, silt contents of 4.8%–21.0%, and soil moisture contents of 10%–30% as used in this work, the average value of R is 0.31. The effects of wind velocity, silt content, and moisture content on the reduction efficiencies are also discussed.

scholarly journals Estimates of Soil Renewal Rates: Applications for Anti-Erosion Arrangement of the Agricultural Landscape

Geosciences ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 266 ◽  
Author(s):  
Fedor Lisetskii
Keyword(s):  
Organic Carbon ◽  
Soil Quality ◽  
Humus Horizon ◽  
Agricultural Landscape ◽  
Soil Formation ◽  
Agricultural Landscapes ◽  
Crimean Peninsula ◽  
History Of ◽  
T Values ◽  
Over Time

Engineering and geographic substantiation of the anti-erosion organization of agricultural landscapes requires not only differentiated estimations of erosion losses, but also commensurate (in terms of space–time scales) estimations of the soil loss tolerance. The main approaches for determining the participation of estimations of soil formation in the substantiation of erosion tolerance have been defined. This study is aimed at justifying the methods of incorporating the results of pedogenesis modeling into computational methods for organizing agricultural landscapes. This paper presents the results of a study of the process of formation of the humus horizon and the accumulation of organic carbon in soils, based on soils from archaeological sites in the Crimean Peninsula over a period from 25 to 2000 years ago, with differences in climate and parent rock, in a region with a thousand-year history of human activity. The patterns of variation in the thickness of the humus horizons over time and the accumulation of carbon were determined, and estimates for the rate of the pedogenesis were obtained. In connection with the slowing of the rate of pedogenesis over time, the chronofunction of the change in the thickness of soils (of both exponential and logistic types) may be applied and, on this basis, it is possible to calculate the rates of the formation of the humus horizon depending on the morphological status of the soils. During re-naturation of highly degraded soils, maximum renewal rates may take place only with a very high input of organic matter, which is crucial to take into account in the development and implementation of programs for the rehabilitation of degraded lands. Under the conditions of slope agriculture, the rationale for T-values should be linked to many factors of the input and consumption of organic carbon, which provides a logical mathematical model of the formation of soil quality. For soil quality management on agricultural lands, a formula for calculating T-values, using an equation where the rate of pedogenesis is associated with a variety of changes in soil organic carbon, is proposed in this article.

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