The nylon 66/nano-CaCO3 composites were prepared by melt blending on a twin-screw extruder. Scanning electron microscopy (SEM), polarized light microscopy (PLM), thermal loss (TGA) and differential scanning calorimetry (DSC) The effects of nanometer calcium carbonate on the polycrystalline behavior and thermal properties of nylon 66/nano CaCO3 composites were investigated. The results show that the nanometer calcium carbonate particles are dispersed in the nylon 66 matrix and exist in the form of aggregates. The nanometer calcium carbonate has the effect of heterogeneous nucleation, which can reduce the size of the spherules. The decomposition temperature of the nylon 66 is 400 ℃, the addition of nano-CaCO3 to reduce the decomposition temperature. At the same time, DSC test showed that the β-crystalline form in the material reduced the melting temperature of the material. The addition of nano-CaCO3 in the nylon 66 matrix resulted in the decrease of the crystallization temperature and the increase of the half-height width of the endothermic peak. The lower the crystallization temperature, the wider the crystallization temperature range.
This study introduces a novel Groundwater Flooding Risk Assessment (GFRA) model to evaluate risks associated with groundwater flooding (GF), a globally significant hazard often overshadowed by surface water flooding. GFRA utilizes a conditional probability function considering critical factors, including topography, ground slope, and land use-recharge to generate a risk assessment map. Additionally, the study evaluates the return period of GF events (GFRP) by fitting annual maxima of groundwater levels to probability distribution functions (PDFs). Approximately 57% of the pilot area falls within high and critical GF risk categories, encompassing residential and recreational areas. Urban sectors in the north and east, containing private buildings, public centers, and industrial structures, exhibit high risk, while developing areas and agricultural lands show low to moderate risk. This serves as an early warning for urban development policies. The Generalized Extreme Value (GEV) distribution effectively captures groundwater level fluctuations. According to the GFRP model, about 21% of the area, predominantly in the city's northeast, has over 50% probability of GF exceedance (1 to 2-year return period). Urban outskirts show higher return values (> 10 years). The model's predictions align with recorded flood events (90% correspondence). This approach offers valuable insights into GF threats for vulnerable locations and aids proactive planning and management to enhance urban resilience and sustainability.
The present study demonstrates the effect of direct solar drying (DSD) and hot air drying (HAD) on the quality attributes of Fuji apple slices. DSD samples took a longer time (150–180 min) to dry and simultaneously reached higher equilibrium moisture content at the end of rehydration than HAD samples. DSD samples have higher rehydration ability, dry matter holding capacity, and water absorption capacity than HAD samples. Among several empirical models, the Weibull model is the best fit with higher R2 (0.9977), lower root mean square (0.0029), and chi-square error (0.0031) for describing the rehydration kinetics. Rehydrated HAD samples showed better color characteristics than DSD in terms of overall color change, chroma, and hue angle values. Whereas the hardness and chewiness of rehydrated DSD samples were better than HAD samples because of higher dry matter holding capacity in DSD. Apart from color retention, the DSD samples showed better rehydration capacity and a good texture upon rehydration than HAD slices.
This work was carried out with the purpose of generating ecological and silvicultural information oriented to sustainable management. The horizontal structure was evaluated using the importance value index of Curtis and Macintosh, the vertical structure using Finol’s methodology. Through the sociological position index, the percentage natural regeneration and the extended importance value index were estimated in order to infer the permanence of the forest ecosystem. The floristic composition was represented by species of the families Anacardiaceae, Apocynaceae, Fabaceae, Santalaceae, Rhamnaceae, Sapotaceae, Simarubaceae, Ulmaceae, Zygophyllaceae, Capparidaceae, Borraginaceae and Achatocarpaceae. In the horizontal structure, the species with the highest rank was Acacia praecox, followed in order of importance by Schinopsis balansae, Aspidosperma quebracho blanco and Prosopis kuntzei. According to sociological position, Acacia praecox was the most representative species, followed by Patagonula americana, Schinus longifolius, Proposis kuntzei and Aspidosperma quebracho blanco. The species with the best regeneration values were Achatocarpus nigricans and Acacia praecox in the shrub layer and Patagonula americana in the tree layer. The extended importance index consolidated the category of Acacia praecox in the community and gave a better category to Schinopsis balansae, Aspidosperma quebracho blanco, Prosopis kuntzei and Patagonula americana.
Implementing green retrofitting can save 50–90% of energy use in buildings built worldwide. Government policies in several developed countries have begun to increase the implementation of green retrofitting buildings in those countries, which must rise by up to 2.5% of the lifespan of buildings by 2030. By 2050, it is hoped that more than 85% of all buildings will have been retrofitted. The high costs of implementing green retrofitting amounting to 20% of the total initial construction costs, as well as the uncertainty of costs due to cost overruns are one of the main problems in achieving the implementation target in 2050. Therefore, increasing the accuracy of the costs of implementing green retrofitting is the best solution to overcome this. This research is limited to analyzing the factors that influence increasing the accuracy of green retrofitting costs based on WBS, BIM, and Information Systems. The results show that there are 10 factors affecting the cost accuracy of retrofitting or customizing high-rise office buildings, namely Energy Use Efficiency, Water Use Efficiency, Use of Environmentally Friendly Materials, Maintenance of Green Building Performance during the Use Period, Initial Survey, Project Information Documents, Cost Estimation Process, Resources, Legal, and Quantity Extraction applied. These factors are shown to increase the accuracy of green retrofitting costs.
This research was conducted with the aim of developing indexes for diagnosis of balanced personnel levels in Korean Public Offices through Analytic Hierachy Process (AHP). The research found that 62.3% of ‘structural improvement’ and 37.7% of ‘inclusive organizational culture’ were weighted in large classification items. In the middle classification items, it was found weights of 27.5% for ‘gender equality’, 23.5% for ‘disabled’, 16.2% for ‘science and engineering’, 17.7% for ‘regional talent’, and 15.2% for ‘social integrated type’. In the small classification items, 9.4% of ‘employment rate of social integrated talent’, 5.3% of ‘the percentage of grade 7 and 9 selection of regional talent’ and 5% of ‘the percentage of women at the head of a department level’ were shown as important evaluation indicators. In addition, the ‘inclusive organizational culture’ was derived by allocating weights of 9.45% each for four areas: fairness, disclosure, cooperation and support. As above, this research constructs items of the balanced personnel index through prior research and designs detailed indexes. However, it is meaningful that surveys and others have confirmed the usefulness of the balanced personnel index, which will contribute to the achievement of balanced personnel objectives in public offices.
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