Fuzzy mathematical model for estimating wind erosion based on wind tunnel data, comparison of results with laboratory measured and SWEEP model results

2021 ◽  
Author(s):  
Károly Tatárvári ◽  
Attila Piros
Keyword(s):  
Mathematical Model ◽  
Wind Speed ◽  
Wind Tunnel ◽  
Fuzzy System ◽  
Soil Loss ◽  
Evaluation System ◽  
Wind Erosion ◽  
Fuzzy Evaluation ◽  
Triangle Diagram ◽  
The Mathematical Model

<p>Fuzzy logic is often used for calculation and simulation of real environmental situations. Wind erosion can often be complex, and from various erosion situations it is one of the hardest to be calculated and exactly described. In our research, we based the structure of the fuzzy system on the soil loss of six soils with different mechanical compositions measured in wind channels. Measurement of soil loss in four wind speed ranges during soil channel testing of soils. During the wind tunnel analysis of the soils, the topsoil loss was measured in four wind speed ranges (I. 11,2-11,6 m/s; II. 12.5-13.3 m/s, III. 14.4-14.7 m/s, IV. 15.5-15.7 m/s) on six soils with different mechanical compositions (four sand and two clayey sand soil). The mathematical model programmed and built up in MATLAB, this mamdani type fuzzy evaluation system uses two input parameters wind speed and ErosionFactor. The mathematical model requests the soils mechanical composition and identifies it based on the USDA triangle diagram. Many mathematical methods applicable to fine tune a fuzzy system. We have chosen the method of exhaustive design to cover the whole parameter space. The mathematical model calculated the soil loss. Model runs were also performed with the SWEEP model according to the soils examined in the wind tunnel. Based on our results, we found that using our fuzzy mathematical model, we obtained estimated soil loss values similar to the SWEEP model compared to the soil loss measured in the wind tunnel. However, it should be noted that the USDA SWEEP model requires a much larger amount of data to estimate the extent of soil loss caused by a wind erosion damage event.</p>

A model to predict the effects of prostrate ground cover on wind erosion

Soil Research ◽  
1990 ◽  
Vol 28 (4) ◽  
pp. 609 ◽  
Author(s):  
PA Findlater ◽  
DJ Carter ◽  
WD Scott
Keyword(s):  
Wind Speed ◽  
Wind Tunnel ◽  
Physical Model ◽  
Soil Loss ◽  
Wind Erosion ◽  
Ground Cover ◽  
Threshold Level ◽  
Simple Physical Model ◽  
Aerodynamic Roughness ◽  
Soil Flux

This paper presents a simple physical model which assumes that the loss of soil is proportional to the fraction of the uncovered ground, when the aerodynamic roughness is small. Integration shows that the total soil loss decreases exponentially with the fraction of ground covered. The model is compared with the soil flux generated in a portable wind tunnel over prostrate lupin residues and results from other studies. The data are well described by the model. Unexpectedly, the same data seem to predict soil fluxes that are not necessarily proportional to the cube of the excess wind speed above the threshold level.

Mathematical Modeling of Steppe Fires

2020 ◽  
pp. 48-62 ◽  
Author(s):  
Valeriy Afanasievich Perminov
Keyword(s):  
Mathematical Modeling ◽  
Mathematical Model ◽  
Wind Speed ◽  
Vegetation Cover ◽  
Meteorological Conditions ◽  
Condensed Phases ◽  
Pyrolysis Products ◽  
Rate Of Spread ◽  
The Mathematical Model ◽  
Steppe Fires

The chapter presents a mathematical model of the initiation and spread of the steppe fire. The mathematical model is based on the laws of mechanics of multiphase reacting media. The main physicochemical processes describing the drying, pyrolysis, and combustion of gaseous and condensed pyrolysis products are taken into account. As a result of the numerical solution, the distributions of the velocity, temperature, and concentration fields of the components of the gas and condensed phases were determined. The dependence of the rate of spread of the steppe fire on the main parameters of the state of vegetation cover and wind speed was studied. The mathematical model presented in the chapter can be used to predict the spread of steppe fires for various types of steppe vegetation and meteorological conditions, as well as for preventive measures.

Artificial intelligence with fuzzy logic system for learning management evaluation in higher educational systems

2020 ◽  
pp. 1-11
Author(s):  
ZhiYuan Lv ◽  
Hengyun Shen
Keyword(s):  
Artificial Intelligence ◽  
Mathematical Model ◽  
Fuzzy Logic ◽  
Evaluation System ◽  
Learning Experience ◽  
Training Model ◽  
Colleges And Universities ◽  
Teaching Evaluation ◽  
Higher Learning ◽  
The Mathematical Model

In this paper, the mathematical model and algorithm based on knowledge forgetting curve are studied. Through the analysis of the current mathematical modeling and application of “knowledge forgetting curve”, the artificial intelligence method of fuzzy mathematics knowledge and differential modeling is adopted. This paper puts forward the mathematical model and algorithm design of the new “knowledge forgetting curve”, which aims to improve the intelligence of the software and bring a new learning experience for the teaching evaluation of the education system in colleges and universities. The fuzzy logic theory is applied to the teaching evaluation system of higher learning pedagogy, according to pedagogy and other related theories, combined with the current teaching evaluation indicators of colleges and universities, the teaching evaluation indicators of higher learning education are set according to certain requirements. The sample wood data is divided into two parts by using the fuzzy logic principle, and the training model is obtained by training the sample data in the evaluation system, and the training model is used to intelligently evaluate and analyze the prediction data.

Research on the Construction of Physical Education Curriculum Evaluation System Based on Information Technology

2014 ◽  
Vol 998-999 ◽  
pp. 1705-1708
Author(s):  
Jing Chao Xu ◽  
Jun Qing Wang ◽  
Jing Li
Keyword(s):  
Mathematical Model ◽  
Physical Education ◽  
Evaluation System ◽  
Curriculum Evaluation ◽  
Fuzzy Evaluation ◽  
Education Curriculum ◽  
Evaluation Theory ◽  
Computer Evaluation ◽  
Comprehensive Fuzzy Evaluation ◽  
Evaluation Matrix

This paper analyzed and researched physical education curriculum evaluation system according to the principle of computer evaluation technique. The first part introduced the physical education curriculum evaluation system this thesis designed the function of the system. The second part of the paper established the mathematical model of the teaching model of physical education through a comprehensive fuzzy evaluation theory and introduced comprehensive fuzzy evaluation matrix form. The third part designed B/S and C/S joint framework model of computer evaluation of PE curriculum combined with comprehensive fuzzy evaluation mathematical model. Finally, this paper designed the Java programming language taking the evaluation of the students about physical education course for example and concluded the implementation form of the data structure table and designed the physical training computer evaluation system.

scholarly journals Windbreak and airflow performance of different synthetic shrub designs based on wind tunnel experiments

PLoS ONE ◽  
2020 ◽  
Vol 15 (12) ◽  
pp. e0244213
Author(s):  
Xia Pan ◽  
Zhenyi Wang ◽  
Yong Gao ◽  
Zhengcai Zhang ◽  
Zhongjv Meng ◽  
...  
Keyword(s):  
Wind Speed ◽  
Wind Tunnel ◽  
Wind Erosion ◽  
Protective Effects ◽  
Wind Tunnel Experiments ◽  
Speed Reduction ◽  
Environmental Threats ◽  
Wind Speeds ◽  
Airflow Field ◽  
Reduction Effect

Wind erosion has gained increasing attention as one of the most serious global ecological and environmental threats. Windbreaks are effective at decreasing wind erosion by reducing wind speed to protect crops, livestock, and farmsteads, while providing wildlife habitats. Synthetic shrubs can act as novel windbreaks; however, there is limited knowledge on how their design affects wind speed. This study determined the protective effects (airflow field and sheltering efficiency) based on the design of synthetic shrubs in a wind tunnel. Broom-shaped synthetic shrubs weakened the wind speeds mainly at the middle and upper parts of the shrubs (5–14 cm), while for hemisphere-shaped shrubs this effect was greatest near their bases (below 4 cm) and least in the middle and upper parts (7–14 cm). Spindle-shaped synthetic shrubs provided the best reduction effect in wind range and strength. Moreover, the wind speed reduction ratio decreased with improved wind speeds and ranged from 26.25 cm (between the second and third rows) to 52.5 cm (after the third row). These results provide strong evidence that synthetic shrubs should be considered to decrease wind speed and prevent wind erosion.

scholarly journals Simulated Experiment on Wind Erosion Resistance of Salix Residual in the Agro-Pastoral Ecotone

2021 ◽  
Vol 9 ◽  
Author(s):  
Qiang Li ◽  
Furen Kang ◽  
Zheng Zhang ◽  
Chunyan Ma ◽  
Weige Nan
Keyword(s):  
Wind Tunnel ◽  
Soil Loss ◽  
Wind Erosion ◽  
Erosion Resistance ◽  
Field Surveys ◽  
Residual Biomass ◽  
Soil Wind Erosion ◽  
Simulated Experiment ◽  
Residual Thickness ◽  
Simulated Wind

Plant residual is of great importance in retarding soil wind erosion in the agro-pastoral ecotone. However, few studies have determined the effects of sand plant residual on wind erosion resistance. Based on field surveys, the influences of Salix residual biomass of 200, 400, 600, and 800 g m−2, soil incorporated with a residual thickness of 0.5, 1.0, and 2.0 cm, and typical proportion of residual branches and leaves (2:1, 1:1, and 1:2) on wind erosion resistance were investigated using a simulated wind tunnel. The results showed the following: 1) The soil loss amount ranged from 1.56 to 40.8 kg m−2 as Salix residual biomass decreased from 800 to 0 g m−2, with a critical residual biomass value of 400 g m−2. 2) As the thickness of soil-incorporated residual increased, the soil loss amount reduced rapidly, especially for 0–9 cm above the surface accounting for 84.6% of the total. 3) Salix branch residual is more important in resisting soil wind erosion as compared with its leaves. This kind of study may provide theoretical explanations for the optimal reconstruction of sandy vegetation in the northern wind-sand regions.

A wind tunnel experiment to explore the feasibility of using beryllium-7 measurements to estimate soil loss by wind erosion

2013 ◽  
Vol 114 ◽  
pp. 81-93 ◽  
Author(s):  
Ming-Yi Yang ◽  
Des E. Walling ◽  
Xi-Jun Sun ◽  
Feng-Bao Zhang ◽  
Bo Zhang
Keyword(s):  
Wind Tunnel ◽  
Soil Loss ◽  
Wind Erosion ◽  
Wind Tunnel Experiment

scholarly journals APPROACH TO DETERMINING BOUNDARY CONDITIONS ON THE EXTERNAL SURFACE OF THE HEIGHT CASE OF THE ADMINISTRATIVE BUILDING

2021 ◽  
pp. 73-79
Author(s):  
N.О. ORLOVA
Keyword(s):  
Heat Transfer ◽  
Mathematical Model ◽  
Wind Speed ◽  
Air Temperature ◽  
Thermal Regime ◽  
Energy System ◽  
Building Envelope ◽  
Transfer Coefficients ◽  
Heat Transfer Coefficients ◽  
The Mathematical Model

Problem statement. The influence of the external climate on the thermal regime of the enclosures of premises and buildings is complex. The calculated values and combinations of parameters are determined, as a rule, taking into account the security factor of the calculated conditions. The main indicators of the cold season are the outdoor temperature and wind speed. As you know, an increase in wind speed with a constant outside air temperature causes an increase in pressure on the windward facade of the building, as a result of which the heat loss of the room, associated with heating of the incoming air, increases. Wind speed and direction have a stronger influence on the distribution of air flows in the ventilation system and on the infiltration costs than the outside temperature. A change in the outside air temperature from −15 to −30 °С leads to the same increase in air exchange in the apartment as an increase in wind speed from 3 to 6 m/s. The purpose of the article is to determine the heat transfer coefficients on the outside of an office building. Results. The basic principles of calculating heat transfer coefficients are presented. The zoning of the premises of the Institute is proposed, taking into account their thermal regime and boundary conditions on external surfaces. Scientific novelty and practical significance. The original values of the heat transfer coefficients, which are considered on the example of the climatic conditions of the city of Kharkov for the IP Mash complex of the NAS of Ukraine. On the basis of the presented methodology for determining the heat transfer coefficients, it is planned to present this building as a single energy system with three main energetically interconnected subsystems: the energy effect of the external climate on the building envelope; energy that is contained in the building envelope, that is, in the external building envelope; energy, which is contained within the volume of the building, that is, in the internal air, internal equipment, internal structures, etc. Then the mathematical model of the building as a unified energy system will consist of three submodels: the mathematical model of the influence of the external climate on the building envelope; mathematical model of heat transfer through the building envelope; mathematical model of radiant and convective heat transfer in the premises of the building.

PV Array Mathematical Model Optimization Considering Wind Speed and Based on Real-Time Monitoring Data

2013 ◽  
Vol 368-370 ◽  
pp. 1266-1269
Author(s):  
Qian Wen Zhong ◽  
Yi Ze Sun ◽  
Jie Yang ◽  
Yang Xu
Keyword(s):  
Mathematical Model ◽  
Wind Speed ◽  
Real Time ◽  
Detection System ◽  
Model Optimization ◽  
Time Data ◽  
Pv Array ◽  
Optimized Model ◽  
The Mathematical Model ◽  
Generating System

Real-time data acquired by real-time detection system -Sunny Sensor Box-for Donghua University power generating system is utilized, and the mathematical model of the PV array for engineering is optimized by considering the effect of the wind speed upon the module temperature. Furthermore, the optimized model has been proved with higher accuracy.

Study on Soil Erosion by Wind Tunnel Experiment of Semi-Arid Steppe in Inner Mongolia

2012 ◽  
Vol 518-523 ◽  
pp. 4766-4770
Author(s):  
Lan Gao ◽  
Yu Jun Qiu ◽  
Xue Yong Zou ◽  
Ren De Wang ◽  
Na Zhou
Keyword(s):  
Particle Size ◽  
Wind Speed ◽  
Wind Tunnel ◽  
Soil Erosion ◽  
Moisture Content ◽  
Inner Mongolia ◽  
Erosion Rate ◽  
Wind Erosion ◽  
Sand Transport ◽  
Average Particle

The characteristics of soil erosion of steppe in Inner Mongolia were studied in wind-tunnel tests. The results indicated that the soil in this region consists primarily of sand and coarse silt, with particle sizes mainly between 0.02 and 1mm, and it is defined as erodible sandy soil. The eroded sediments are mainly concentrated at heights of 0~24cm, and the extreme value of particle size is clearly in the range 100~300μm. Average particle size increased with increasing wind speed, and it decreased exponentially in the vertical direction, reflecting the characteristics of sand transport by wind. The relationship between wind erosion rate and wind speed assumes a power function with correlation coefficients greater than 0.9. A wind speed of 15m/s is a significance point above which wind erosion in this region becomes very large. Soil erosion rate decreases logarithmically as soil moisture content and vegetation coverage increase, and the 5% level of moisture content is a turning point.

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