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NGC 6860, Mrk 915, and MCG -01-24-012
No full textWe present a study of the cold molecular gas kinematics in the inner ∼4–7 kpc (projected sizes) of three nearby Seyfert galaxies with active galactic nucleus (AGN) luminosities of ∼1044 erg s−1 using observations of the CO(2–1) emission line obtained with the Atacama Large Millimeter/submillimeter Array (ALMA) at ∼0.5–0.8″ (∼150–400 pc) spatial resolutions. After modeling the CO profiles with multiple Gaussian components, we detected regions with double-peak profiles that exhibit kinematics distinct from the dominant rotational motion. In NGC 6860, a molecular outflow surrounding the bipolar emission of the [O II
Research on the Influence of Technological Parameters and the Physicochemical Properties of the C
No full textThis article presents the results of a study on the influence of technological parameters on the physicochemical properties of the EDTA-4Na - FeCl3 - H2O system within a wide range of selected technological parameters. Specifically, the effect of the concentration of FeCl3 solutions and their ratio relative to EDTA-4Na was investigated. It was found that with an increase in the EDTA-4Na ratio, the system's pH increases from 1.271 - 1.608 to 2.938 - 4.117 and 6.426 - 7.795. Furthermore, with an increase in FeCl3 concentration at a constant ratio, a slight decrease in pH is observed up to 30%, followed by a sharp increase at 40%. Further increase in FeCl3 concentration leads to a slight decrease. This pattern is consistent across all ratios. The pH difference of the system when using 30% and 10% FeCl3 solutions is 0.216, 2.89, and 1.327 at ratios of 50, 100, and 150%, respectively
Soil response and behavior to megathrust earthquakes using the deterministic seismic hazard analysis (DSHA) method in Yogyakarta City
No full textNatural disasters are events caused by natural phenomena, one of which is earthquakes. Earthquakes are among the natural disasters that may occur due to tectonic movements as well as volcanic activities such as volcanic eruptions. Tectonic earthquakes occur as a result of the movement of tectonic plates, where the Earth is seeking its point of stability. Yogyakarta City, located on the island of Java, is highly vulnerable to earthquakes because it lies within the Ring of Fire and is traversed by many fault zones that have the potential to generate earthquakes. Based on the results of seismic data processing, it was found that the soil in Yogyakarta City is classified as stiff soil, which is relatively soft and prone to liquefaction. The vibrations felt in Yogyakarta City are twice as strong compared to those at the earthquake source, and this is caused by differences in the resistance of the rock formations that make up Yogyakarta City and the earthquake source. The resonance effects on buildings are strongly perceived in structures with heights ranging from two to five stories compared to those on the ground surface
Exploring the nexus between renewable energy, climate and disaster risk reduction, and land use planning: The case of Paete, Laguna, Philippines
No full textRenewable energy presents a plausible strategy for empowering communities by achieving energy self-reliance and security while ensuring balanced economic growth and environmental protection amidst global climate change, such is the case in the Philippines, as iterated in the Renewable Energy Act of 2008. However, such an option creates debate concerning food security, environmental protection, and sustainable development. The study delves into scrutinizing the policy guidelines on balancing wind energy development and protection of the natural landscape through the zoning ordinance of Paete, Laguna, linked with land use planning efforts in lieu of climate and disaster risk reduction and management, and renewable energy production. Results show that dialogues, participatory mapping, land use planning efforts, including Climate and Disaster Risk Assessment and Environmental Impact Assessment and community-led zoning, may allow the proper mix of policy regulations and stakeholder participation and accountability, all towards achieving sustainable development. It exemplifies the interconnectedness and challenges of linking renewable energy and sustainable energy through the sustainable development planner triangle lens, where community conflicts and challenges arising from development may present solutions towards sustainable development. All these are integrated into the study recommendations aligned to the local zoning that other local governments may adopt
Performance evaluation of steam and membrane curing on geopolymer mortar with fly ash and carbide waste
No full textThis study evaluates the performance of steam and membrane curing methods on the compressive strength of geopolymer mortar incorporating fly ash and carbide waste. Cube specimens measuring 5×5×5 cm were prepared with fly ash proportions of 100%, 80%, 60%, and 40%, combined with carbide waste at 0%, 20%, 40%, and 60%. After casting, the specimens were cured using two methods: (1) membrane curing by wrapping in impermeable plastic, and (2) steam curing at ±70 °C for approximately 2 hours, followed by cooling and wrapping. Compressive strength tests were conducted at 7, 14, and 28 in accordance with SNI 6882:2014. The results show that steam curing consistently produced higher compressive strength compared to membrane curing across all mixture variations. At 28 days, the highest compressive strength under steam curing reached 52.66 MPa for the 100% fly ash mixture. For the 40% fly ash and 60% carbide waste mixture, steam curing achieved 25.76 MPa. These findings confirm that steam curing accelerates geopolymerization, resulting in a denser matrix and higher strength development. This study highlights steam curing as an effective approach to enhance the performance of geopolymer mortar incorporating industrial waste materials
Motivational drivers for green manufacturing: The interplay of knowledge, public concern, and regulatory factors in the sugar industry
No full textThe sugar industry is one of the sectors with significant environmental challenges, particularly related to high resource consumption and waste generation. Addressing these issues requires the adoption of green manufacturing practices as part of sustainable industrial transformation. However, the motivation to implement such practices is often influenced by various internal and external factors. This study investigates the motivational drivers behind green manufacturing at Wringin Anom Sugar Factory, Situbondo, focusing on the interplay of knowledge, public concern, and regulatory factors. Primary data were obtained from 30 respondents, with data collection conducted through questionnaires distributed directly to factory employees. Multiple Regression Analysis was employed to examine the extent to which these variables influence motivation. The results reveal that knowledge has a regression coefficient of 0.346 with a significance level of 0.080 (>0.05), indicating no partial effect on motivation. Public concern shows a regression coefficient of 0.473 with a significance level of 0.020 (<0.05), suggesting a significant positive influence. Similarly, regulation demonstrates a regression coefficient of 0.436 with a significance level of 0.011 (<0.05), confirming its significant contribution. These findings highlight that while knowledge alone may not directly motivate the adoption of green manufacturing, public concern and regulatory enforcement serve as key drivers
Influence of blast design parameters and geological discontinuities on ground vibration: A multivariate regression approach
No full textBlast-induced vibration waves can only propagate when a transmission medium is present. In surface coal mining, this medium is represented by bedding planes. This highlights that vibration analysis cannot rely solely on scale distance but must also consider geological conditions such as bedding orientation. This study analyses the influence of blast hole diameter, number of holes, scale distance, and bedding planes on Peak Particle Velocity (PPV). The bedding plane parameter is defined as the angular difference between the bedding orientation and the blast wave propagation direction, or the angle between the blast boundary and the vibration monitoring point. In other words, the orientation of bedding planes relative to the propagation direction significantly affects the transmission pattern, with vibrations tending to be stronger when aligned with the bedding strike and more attenuated when perpendicular. This study confirms that accurate vibration prediction can only be achieved by integrating both blast design parameters and geological structures. The developed model has the potential to support safer, more efficient, and environmentally responsible blast design in surface mining operations
Integral representations of the solutions to the homogenized transport equations
No full textThis paper provides two general representations of the weak limit u(t,x) of the solution uε(t,x) for (t,x) ∈ (0,T)×Rd, to the linear transport equation with an oscillating regular velocity b(x/ε), an initial datum u0ε(x) and a right-hand side fε(t,x). Our main assumption is the existence of a function w ∈ C1(Rd) such that b · ∇w is bounded from below by a positive constant. As a consequence, the dynamic flow Φ(t,y) associated with the vector field b(y) induces a one-to-one mapping from R×Σ onto Rd, where Σ is the equipotential hypersurface {w = 0}. This assumption allows us to finely characterize the kernel of the differential operator b(y) · ∇y(·) thanks to some quotient set Σb/R, where Σb is a suitable compact subset of Σ. Then, using a two-scale procedure we establish two integral formulas of the limit u(t,x), one over the quotient set and the other one over the d-dimensional torus Td, which involve the two-scales limits of the sequences of data and the projection of b onto the kernel of b(y) · ∇y(·). Finally, we also derive two alternative expressions of the asymptotics of the flow lim∞ Φ(t,y)/t for a.e. y ∈ Td
A review of outdoor and indoor air temperature dynamics and their influence on clothing insulation in dwellings
No full textOutdoor air temperature fluctuates throughout the year and significantly affects indoor temperature, which in turn influences thermal comfort in dwellings. As indoor conditions change, occupants tend to adjust their clothing to maintain comfort. While many studies have examined air temperature variation and its effect on clothing insulation, limited research has explored the connection between indoor and outdoor temperatures across various building operation modes and climates. This review investigates how outdoor air temperature impacts indoor environments in different regions and how this influences clothing insulation, providing insights into thermal comfort behaviour. The Scopus database was used for this review and only relevant articles were selected for this study. The findings show that indoor temperature correlates with outdoor temperature. In free-running buildings, the slope of the indoor and outdoor air temperature regression is 0.64, compared to 0.45 in cooling, heating, or mixed modes, indicating greater sensitivity in non-conditioned spaces. Clothing insulation also decreases with rising indoor and outdoor temperatures, suggesting adaptive clothing behaviour. These results underscore the importance of HVAC systems and appropriate clothing in achieving thermal comfort across varying climatic and operational contexts
Emotional alterations under attentional loads during sustained heat exposure
No full textThe globally escalating heatwaves are threatening people’s well-being by imposing more intensive and longer heat exposures. The emotion is one important aspect frequently affected by heat exposure, especially under mental workload. However, the gap always exists that no quantitative approach/model could facilitate the emotional evaluation. To address this gap, a 150-min heat exposure was conducted at 31℃, 33℃, and 35 ℃, with the relative humidity of 50 ± 3%. The within-subject design was followed among 14 participants. During the heat exposure, four kinds of attentional tasks were administered continuously to simulate the mental workloads, and the skin temperature was continuously recorded with the 4-point method. Besides, the Brunel Mood Scale (BRUMS) was completed to acquire the emotional changes. Results showed that ‘depression’ and ‘fatigue’ subscale of the BRUMS increased with both the environmental temperature and exposure time, which indicated that the emotion had been negatively affected. Meanwhile, the mean skin temperature rose with the temperature and exposure time by almost 1.2 ℃. Based on that, correlation analysis was conducted. Results indicated that the emotion ‘depression’ was significantly correlated with mean skin temperature, with the Spearman’s ρ of 0.65 (p<0.05). Thereafter, a linear regression was carried out considering the effective size, and a quantitative model based on the mean skin temperature for the quantitative evaluation of emotions under cognitive-demanding scenarios and in the heat was obtained. Findings of this study provided a potential solution for the objective emotion evaluation of mental-demanding workers who have to work in the heat