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111.
Ertugrul Yildirim Alper Aslan Ilhan Ozturk 《Renewable & Sustainable Energy Reviews》2012,16(8):6123-6127
The paper investigates the causality relationships among industrial production index, coal consumption and employment in industrial sector for the period of 1973:1–2011:10 in USA. After noticing that there are breaks in the regression model, the Hatemi-J test for cointegration is employed to the cases that take into account two possible regime shifts. It is concluded that there is a long run relationship between industrial production and industrial coal consumption with the breaks at 1983:4 and 1998:4. We found a negative relationship between coal consumption and industrial production for the period of 1973:1–1983:4 and positive relationship for 1983:5–1998:4 period. For the last period that covers 1983:5–2011:10, the cointegration relationship turned to negative. In addition, the results show that causal relationship between coal consumption and industrial production changes over time. 相似文献
112.
This paper examines the long run and causal relationship issues between economic growth, carbon emissions, energy consumption and employment ratio in Turkey by using autoregressive distributed lag bounds testing approach of cointegration. Empirical results for Turkey over the period 1968–2005 suggest an evidence of a long-run relationship between the variables at 5% significance level in Turkey. The estimated income elasticity of carbon emissions per capita is ?0.606 and the income elasticity of energy consumption per capita is 1.375. Results for the existence and direction of Granger causality show that neither carbon emissions per capita nor energy consumption per capita cause real GDP per capita, but employment ratio causes real GDP per capita in the short run. In addition, EKC hypothesis at causal framework by using a linear logarithmic model is not valid in Turkish case. The overall results indicates that energy conservation policies, such as rationing energy consumption and controlling carbon dioxide emissions, are likely to have no adverse effect on the real output growth of Turkey. 相似文献
113.
The main scope of this comprehensive study is to investigate the effects of poly(p-benzophenoneoxycarbonylphenyl acrylate), poly(BPOCPA), which presenting as only graft units or both graft and ungrafted units in the matrix, on the fundamental features of isotactic polypropylene (IPP). The graft copolymerization of BPOCPA onto IPP was performed with the aid of bulk melt polymerization at varying monomer content levels ranging from 5% to 40%. The thermal behavior, crystal quality, mechanical performance, and surface morphology of the samples were investigated by means of differential scanning calorimeter, X-ray diffractometer (XRD), universal mechanical test, and scanning electron microscope (SEM) techniques. Thermal analyses depicted that there existed the noteworthy enhancements in both crystalline melting temperatures and percent crystallinities of matrix polymers. Furthermore, according to XRD results, a and b parameters increased significantly at low percentages of the graft units, while the parameter c decreased in all products in consistence with the content. As for the mechanical characterization, the grafting led to remarkable improvements in modulus, tensile and impact strength of the products. SEM micrographs indicated that the samples were completely homogeneous without any phase separation and the products exhibited brittle nature with some ductility. 相似文献
114.
In this study, AA7075 aluminum matrix composites reinforced with the combination of SiC, Al2O3, and B4C particles were fabricated by the liquid metal infiltration method. The effects of the relative ratio of B4C and Al2O3 particles on the microstructural, wear, and corrosion features of the composite samples were analyzed using XRD, light metal microscopy, SEM, EDS, Brinell hardness, ball-on-disc type tribometer, and potentiodynamic polarization devices. It was determined that infiltration occurred more successfully, and homogenously distributed particles with reduced porosity were obtained as the amount of Al2O3 increased. Worn surface studies revealed that the specimens were predominantly worn by abrasion and adhesion. The increase in B4C/Al2O3 ratio caused a decrease in the hardness and wear strength, whereas it increased the corrosion resistance. 相似文献
115.
Tekin Ramazan Ertuğrul Ömer Faruk Kaya Yılmaz 《Multimedia Tools and Applications》2020,79(43-44):32541-32561
Multimedia Tools and Applications - In this paper, four novel, simple and robust approaches, which are left to right local binary patterns (LBPLL2R), top to down local binary patterns (LBPT2D),... 相似文献
116.
Food Science and Biotechnology - In the present study, variety of fruit vinegars were investigated in terms of their physicochemical, microbiological and bioactive properties. Total phenolic and... 相似文献
117.
118.
Güler Onur Çelebı Müslım Dalmış Ramazan Çanakçi Aykut Çuvalci Hamdullah 《Metallurgical and Materials Transactions A》2020,51(9):4632-4646
Metallurgical and Materials Transactions A - In this study, nanosized B4C and graphite-reinforced ZA27 matrix hybrid nanocomposites were produced with mechanical milling followed by hot pressing.... 相似文献
119.
Thermodynamics of inclusion formation in Fe-Cr-Ti-N alloys 总被引:7,自引:0,他引:7
The thermodynamics of titanium in Fe-Cr alloys and of inclusion formation in Fe-Cr-N-Ti alloys was investigated. A metal-nitride-gas
equilibration technique was used to measure the activity of titanium. The equilibrium titanium content of the metal that is
in equilibrium with pure solid titanium nitride and nitrogen gas at 1 atm was determined. The activity coefficients of titanium
it(fTi) relative to 1 wt pct standard state in Fe were calculated for Fe-Cr alloys from the experimental results. The first-order
interaction coefficient between titanium and chromium, e
Ti
Cr
, was determined to be 0.024 at 1873 K. The solubility of nitrogen in Fe-Cr alloys was measured and was found to increase
with chromium content, which is in agreement with previous work. Thermodynamic calculations were made in order to predict
under what conditions titanium nitride will form in 409 stainless steel and was compared with inclusions found in plant samples.
The inclusion stability diagrams for 304 stainless steel and Fe-18 pct Cr and Fe-9 pct Cr alloys were computed. 相似文献
120.
In this paper, an adaptive simulated annealing genetic algorithm is proposed to solve generation expansion planning of Turkey's power system. Least‐cost planning is a challenging optimization problem due to its large‐scale, long‐term, nonlinear, and discrete nature of power generation unit size. Genetic algorithms have been successfully applied during the past decade, but they show some limitations in large‐scale problems. In this study, simulated annealing is used instead of mutation operator to improve the genetic algorithm. The improved algorithm is applied to the power generation system with seven types of generating units and a 20‐year planning horizon. The planning horizon is divided into four equal periods. The new algorithm provides approximately 6.6 billion US$ (3.2%) cheaper solution than GA and also shows faster convergence. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献