Study of nonlinear behaviors of geological materials

2011 ◽  
Vol 6 (5) ◽  
pp. 1613-1620
Author(s):  
Tsun-Hui Huang ◽  
Shyue-Cheng Yang ◽  
Chiou-Fen Shieh
Keyword(s):  
Geological Materials ◽  
Nonlinear Behaviors

COPPER (Cu2+) REMOVAL FROM WATER USING NATURAL ZEOLITE FROM GEDANGSARI, GUNUNGKIDUL, YOGYAKARTA

2015 ◽  
Vol 2 (2) ◽  
Author(s):  
Wahyu Wilopo ◽  
Septiawan Nur Haryono ◽  
Doni Prakasa Eka Putra ◽  
I Wayan Warmada ◽  
Tsuyoshi Hirajima
Keyword(s):  
Waste Water ◽  
Economic Growth ◽  
Heavy Metals ◽  
Natural Zeolite ◽  
Adsorption Equilibrium ◽  
Waste Water Treatment ◽  
Batch Test ◽  
Maximum Capacity ◽  
Geological Materials ◽  
Langmuir Adsorption

Development of indusrialization and urbanization not only increase economic growth but also contribute to the environmental degradation, especially contamination of heavy metals in water. In other side, there are many geological materials have capability to immobilize heavy metals. Therefore, the objective of this research is to know the maximum capacity of natural zeolite from Trembono area, Gunung Kidul regency to immobilize copper (Cu2+) from water and to understand their mechanism. This experiment was carry out by a batch test. The result showed that the maximum capacity of zeolite to immobilize Cu (qmax) is 63,69 mmolCu/kg Zeolite according to Langmuir adsorption equilibrium model. In addition, the capability to immobilize Cu will increases due to decreasing the grain size. The result of this research can be used as an alternative for waste water treatment, especially Cu. Keywords: Removal, copper (Cu2+), natural zeolite, Langmuir isotherm

Convergence in per capita carbon footprint and ecological footprint for G7 countries: Evidence from panel Fourier threshold unit root test

2021 ◽  
pp. 0958305X2110114
Author(s):  
Veli Yilanci ◽  
Muhammed Sehid Gorus ◽  
Sakiru Adebola Solarin
Keyword(s):  
Unit Root ◽  
Structural Breaks ◽  
Structural Changes ◽  
Unit Root Test ◽  
G7 Countries ◽  
Convergence Hypothesis ◽  
International Climate ◽  
Per Capita ◽  
Nonlinear Behaviors ◽  
Nonlinear Unit Root Tests

This paper aims to explore the convergence of per capita carbon and ecological footprints in G7 countries during 1961–2016. For this purpose, we propose a new unit root test in the panel setting–the panel Fourier threshold unit root test. This test takes into consideration both multiple smooth structural changes and nonlinearity. According to the literature, the power of the nonlinear unit root tests is reduced in the case of ignoring structural breaks. Therefore, we expect to get more reliable empirical findings by utilizing this methodology. The empirical results of this paper show that these series have nonlinear behaviors for the period 1961–2016. Furthermore, they demonstrate that the absolute convergence hypothesis is valid in G7 countries for both regimes. Thus, governments can conduct common environmental policies, including international climate summits and agreements, instead of national-based policies to mitigate environmental deterioration in their countries.

scholarly journals STED nanoscopy – A novel way to image the pore space of geological materials

2021 ◽  
Author(s):  
Karl‐Heinz Hellmuth ◽  
Juuso Sammaljärvi ◽  
Marja Siitari‐Kauppi ◽  
Jean‐Charles Robinet ◽  
Paul Sardini
Keyword(s):  
Pore Space ◽  
Geological Materials

scholarly journals Period-doubling bifurcation analysis and chaos control for load torque using FLC

2021 ◽  
Author(s):  
Eman Moustafa ◽  
Abdel-Azem Sobaih ◽  
Belal Abozalam ◽  
Amged Sayed A. Mahmoud
Keyword(s):  
Floquet Theory ◽  
Chaos Control ◽  
Fuzzy Logic Controller ◽  
Chaotic Behavior ◽  
Period Doubling ◽  
Parameter Variation ◽  
Period Doubling Bifurcation ◽  
Load Torque ◽  
Nonlinear Behaviors ◽  
Scientific Fields

AbstractChaotic phenomena are observed in several practical and scientific fields; however, the chaos is harmful to systems as they can lead them to be unstable. Consequently, the purpose of this study is to analyze the bifurcation of permanent magnet direct current (PMDC) motor and develop a controller that can suppress chaotic behavior resulted from parameter variation such as the loading effect. The nonlinear behaviors of PMDC motors were investigated by time-domain waveform, phase portrait, and Floquet theory. By varying the load torque, a period-doubling bifurcation appeared which in turn led to chaotic behavior in the system. So, a fuzzy logic controller and developing the Floquet theory techniques are applied to eliminate the bifurcation and the chaos effects. The controller is used to enhance the performance of the system by getting a faster response without overshoot or oscillation, moreover, tends to reduce the steady-state error while maintaining its stability. The simulation results emphasize that fuzzy control provides better performance than that obtained from the other controller.

Standoff femtosecond filament-induced breakdown spectroscopy for classification of geological materials

2020 ◽  
Vol 35 (12) ◽  
pp. 3007-3020
Author(s):  
S. Abdul Kalam ◽  
S. V. Balaji Manasa Rao ◽  
M. Jayananda ◽  
S. Venugopal Rao
Keyword(s):  
Geological Materials ◽  
Breakdown Spectroscopy ◽  
Remote Locations

Femtosecond (fs) filaments delivering substantial peak intensities at remote locations are exploited in classification of geological materials together with in situ /standoff investigations.

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