scholarly journals Effect of Tillage Method on the Change of Physical Properties of Soil. 1. Characteristics of the Change of Penetration Resistance and Change of Three-Phase Distribution.

1991 ◽  
Vol 26 (2) ◽  
pp. 118-126
Author(s):  
Tadasi KOBAYASHI
Keyword(s):  
Physical Properties ◽  
Phase Distribution ◽  
Penetration Resistance ◽  
Three Phase ◽  
Tillage Method ◽  
Properties Of Soil

scholarly journals Evaluation of selected physical properties of soil in the vineyard

2011 ◽  
Vol 59 (1) ◽  
pp. 269-276
Author(s):  
Pavel Zemánek ◽  
Milan Michálek
Keyword(s):  
Czech Republic ◽  
Physical Properties ◽  
Penetration Resistance ◽  
Critical Limit ◽  
Soil Cultivation ◽  
Production Processes ◽  
Undisturbed Sample ◽  
Soil Compression ◽  
South Moravia ◽  
Properties Of Soil

There is registered approximately 18 000 ha of intensive vineyards in this time in Czech Republic. The intensive viticulture production is represented by high amount of working operations which are practised by using of mechanization. Frequency of passages by mechanization in interrow of descent is different by single variants of production processes. Their currently number varies about 20–25 per season. The soil compression is the highest in wheels tracked lines and middle of the interrow. If the compaction reaches over the critical limit, it can be this state escorted by weighty incidence (decrease of decree, increasing by power severity by soil cultivation and other). These contributions deal with analysis of soil compression in different areas in the region of the South Moravia. The used methods were undisturbed sample and penetration resistance with using of penetrometer.

scholarly journals Optimal Selection of Conductors in Three-Phase Distribution Networks Using a Discrete Version of the Vortex Search Algorithm

Computation ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 80
Author(s):  
John Fernando Martínez-Gil ◽  
Nicolas Alejandro Moyano-García ◽  
Oscar Danilo Montoya ◽  
Jorge Alexander Alarcon-Villamil
Keyword(s):  
Objective Function ◽  
Power Flow ◽  
Phase Distribution ◽  
Search Algorithm ◽  
Distribution Networks ◽  
Discrete Version ◽  
Optimal Selection ◽  
Flow Method ◽  
Three Phase ◽  
Selection Of

In this study, a new methodology is proposed to perform optimal selection of conductors in three-phase distribution networks through a discrete version of the metaheuristic method of vortex search. To represent the problem, a single-objective mathematical model with a mixed-integer nonlinear programming (MINLP) structure is used. As an objective function, minimization of the investment costs in conductors together with the technical losses of the network for a study period of one year is considered. Additionally, the model will be implemented in balanced and unbalanced test systems and with variations in the connection of their loads, i.e., Δ− and Y−connections. To evaluate the costs of the energy losses, a classical backward/forward three-phase power-flow method is implemented. Two test systems used in the specialized literature were employed, which comprise 8 and 27 nodes with radial structures in medium voltage levels. All computational implementations were developed in the MATLAB programming environment, and all results were evaluated in DigSILENT software to verify the effectiveness and the proposed three-phase unbalanced power-flow method. Comparative analyses with classical and Chu & Beasley genetic algorithms, tabu search algorithm, and exact MINLP approaches demonstrate the efficiency of the proposed optimization approach regarding the final value of the objective function.

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