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Environment psychologically affects individuals. According to the base of cognitive psychology, there is a direct relationship between human behavior, environment, and emotional process. Assuming that pleasantness and unpleasantness are associated with peripheral nervous system activation, the current study aims to explore if the pleasant or unpleasant architectural places can stimulate the brain regions engaged in emotions or not. As the main contribution, we used functional magnetic resonance imaging (fMRI) measuring blood oxygenation level-dependent (BOLD) changes to effectively detect the brain's region that mainly responds to the emotional-perceptual processes. Based on the results of examining the emotional assessment model of “Pleasure-Arousal” applied to 140 students, 30 most-rated images representing 15 pleasant and 15 unpleasant places were shown to 32 participants in a 1.5-T MRI scanner. After applying standard preprocessing steps (re-alignment, slice-timing, co-registration, segmentation, normalization, and smoothing) to functional MR images, first-level analysis was applied to each subject. The results were evaluated using statistical corrections at different levels for female and male participants with the second-level analysis. In conclusion, it has been shown that there is a significant linkage between environmental experience and brain activation so that the architectural qualities can change blood flow in specific brain regions.  相似文献   
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Testing safety-critical systems is crucial since a failure or malfunction may result in death or serious injuries to people, equipment, or environment. An important challenge in testing is the derivation of test cases that can identify the potential faults. Model-based testing adopts models of a system under test and/or its environment to derive test artifacts. This paper aims to provide a systematic mapping study to identify, analyze, and describe the state-of-the-art advances in model-based testing for software safety. The systematic mapping study is conducted as a multi-phase study selection process using the published literature in major software engineering journals and conference proceedings. We reviewed 751 papers and 36 of them have been selected as primary studies to answer our research questions. Based on the analysis of the data extraction process, we discuss the primary trends and approaches and present the identified obstacles. This study shows that model-based testing can provide important benefits for software safety testing. Several solution directions have been identified, but further research is critical for reliable model-based testing approach for safety.  相似文献   
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The objective of this work is to produce Al2O3-ZrO2 composite from nano-sized powders processed by coprecipitation method. Al2O3 and mixture of Al2O3 + 10 wt.% ZrO2 precipitated successfully by chemical route from aluminum sulfate and zirconium sulfate were pressed under uniaxial compression of 170 MPa and sintered at 1600 °C for 1 h. SEM investigations revealed that, pure alumina sample has a microstructure with coarse grains which anisotropically grown up to 30-40 μm in size. In alumina-zirconia composite, the structure consists of very fine equiaxed grains of typically 2 μm in which zirconia precipitates were uniformly dispersed. By adding zirconia to alumina, hardness and indentation fracture toughness were increased from 11.6 GPa to 16.8 GPa and from 3.2 MPa m1/2 to 4.9 MPa m1/2, respectively. Improvement in fracture toughness was attributed to bridging effects of zirconia particles as well as transformation toughening.  相似文献   
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The amount of retained austenite in the quenched cold work tool steel sample is 17.7%, in the condition of sub-zero heat treated and double tempered samples following by quenching is 1.9% determined by XRD analysis. The types of carbides (MC, M7C3, M23C6) present in the structure was determined by XRD and SEM-EDS analysis. The hardness of test samples were 865 HV(0.1) for quenched sample and 785 HV(0.1) forth sample subjected to sub-zero treatment and double tempered after the quenching.  相似文献   
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 Heat treatment methods were applied to white cast iron for improving the impact and wear resistance. Additionally, chemical composition optimization was made. Furthermore, the effect of boron addition on such applications was investigated. Samples were investigated by using optical and electron microscope methods. Hardness, wear and impact tests were conducted. The results showed that the secondary carbides in the standard alloy were iron-enriched, needle-like carbides M3C when the boron-added alloy contained Fe23(C,B)6 type, globular secondary carbides. It was concluded that heat treatment B provided higher wear and hardness properties, compared to the standard heat treatment. Optimum mechanical properties were obtained by lower destabilisation temperatures and increasing temperature reduced the wear resistance and hardness.  相似文献   
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 It is known that dual phase (DP) heat treatments and alloying elements have a strong effect on martensitic transformations and mechanical properties. In the present work, the effects of some intercritical annealing parameters (heating rate, soaking temperature, soaking time, and quench media) on the microstructure and mechanical properties of cold rolled DP steel were studied. The microstructure of specimens quenched after each annealing stage, was analyzed using optical microscopy. The tensile properties, determined for specimens submitted to complete annealing cycles, are influenced by the volume fractions of multi phases (originated from martensite, bainite and retained austenite), which depend on annealing processing parameters. The results obtained showed that the yield strength (YS) and the ultimate tensile strength (UTS) increase with the increasing intercritical temperature and cooling rate. This can be explained by higher martensite volume ratio with the increased volume fraction of austenite formed at the higher temperatures and cooling rates. The experimental data also showed that, for the annealing cycles carried out, higher UTS values than ~ 800 MPa could be obtained with the S3 steel grade.  相似文献   
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Hydrogen is considered in many countries to be an important alternative energy vector and a bridge to a sustainable energy future. Hydrogen is not an energy source. It is not primary energy existing freely in nature. Hydrogen is a secondary form of energy that has to be manufactured like electricity. It is an energy carrier. Hydrogen can be produced from a wide variety of primary energy sources and different production technologies. About half of all the hydrogen as currently produced is obtained from thermo catalytic and gasification processes using natural gas as a starting material, heavy oils and naphtha make up the next largest source, followed by coal. Currently, much research has been focused on sustainable and environmental friendly energy from biomass to replace conventional fossil fuels. Biomass can be considered as the best option and has the largest potential, which meets energy requirements and could insure fuel supply in the future. Biomass and biomass-derived fuels can be used to produce hydrogen sustainably. Biomass gasification offers the earliest and most economical route for the production of renewable hydrogen.  相似文献   
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