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Exploring the Impact of Relational and Geographic Search on Firm Innovation
Get PDFThis paper explores the interplay between geographic and relational search behaviors and their impact on innovation generation within firms. Extending previous research, our study explores the dual influences of geographic proximity and relational dynamics on both the quantity and quality of innovations. We develop a conceptual framework to examine the combined effects of these factors, identifying four distinct types of firm knowledge search behaviors and analyzing their repercussions on innovation outcomes. The study highlights the necessity for managers to adopt a balanced approach in strategic knowledge search. By acknowledging the trade-offs between different search strategies, managers can more effectively navigate the complexities of innovation processes. This balanced approach is essential for optimizing innovation outcomes and achieving sustained success in a rapidly changing business environment. Our study emphasizes the importance of a nuanced understanding of geographic and relational searches. By integrating these insights into their strategic planning, firms can enhance their capability to generate both incremental and breakthrough innovations, thereby strengthening their competitive position in the market. This paper provides valuable guidelines for firms aiming to enhance their innovation portfolios through informed and strategic knowledge search behaviors
Six Stroke Engine Optimization for Mid to High Loads Using Genetic Algorithm
No full textThe development of new internal combustion (IC) engine technologies is essential as the automotive industry moves towards hybrid powertrains. Six-stroke (6S) gasoline compression ignition (GCI) engine is one such promising technology. It has the potential to improve performance and reduce emissions by introducing an additional power stroke (PS2) after the first power stroke (PS1). The aim of this study was to determine the optimal injection parameters for 6S GCI operation with one injection event in each power stroke. Parameters included the start of first (SOI1) and second injection (SOI2), and the fuel split ratio (SR) between PS1 and PS2. The study focused on mid (12, 15 bar) to high (18, 21 bar) engine loads, relevant for hybrid powertrains. Genetic algorithm technique was employed to optimize thermal efficiency while adhering to constraints on soot, NOx, maximum pressure rise rate (MPRR), and peak cylinder pressure (PCP). For 12 bar load, delaying the SOI1 timing to -4 CA ATDC led to PS1 misfire and kinetically-mixing controlled (K-MCM) combustion in PS2, minimizing overall heat loss thus giving the highest efficiency. SR of 60% was found to be optimal, constrained by MPRR. At 15 bar, there was close competition between PS2 kinetically-mixing controlled mode (K-MCM) ignition only and a combined PS1 KCM + PS2 MCM combustion mode. For higher loads of 18 and 21 bar, both power strokes needed ignition to meet the constraints, with KCM in PS1 and MCM in PS2 proving to be the most effective strategy. As the load increased from 15 to 21 bar, the SR had to be reduced to comply with MPRR constraints. The SOI2 timing was adjusted to balance thermal efficiency with NOx and MPRR limits
Lanthanum-based nanoparticles: A promising frontier in antimicrobial applications
Get PDFLanthanum-based nanoparticles have garnered significant attention for their potential in antimicrobial applications due to their unique properties and mechanisms of action. This review explores the antimicrobial efficacy of various lanthanum-based nanoparticles, including La2O3, La(OH)3, and LaF3, highlighting their mechanisms of action such as disruption of microbial cell walls, generation of reactive oxygen species (ROS), and interference with microbial DNA and protein synthesis. Despite their promising attributes, several challenges hinder their practical application, including limited understanding of their mechanisms, concerns over biocompatibility and toxicity, and difficulties in scaling up production. Emerging trends in nanoparticle research, such as surface functionalization, smart delivery systems, and green synthesis methods, present innovative approaches to enhance the efficacy and sustainability of lanthanum-based nanoparticles. Additionally, integrating these nanoparticles into advanced materials and exploring combination therapies offer new possibilities for expanding their applications. Future research should focus on elucidating the detailed mechanisms of antimicrobial action, conducting comprehensive biocompatibility and environmental impact studies, and developing scalable and cost-effective synthesis methods. Addressing these challenges and embracing emerging trends will be crucial for advancing the application of lanthanum-based nanoparticles and leveraging their benefits for improved antimicrobial solutions in both clinical and industrial contexts. This review provides a comprehensive overview of the current state of research on lanthanum-based nanoparticles, identifying key areas for further investigation and highlighting their potential to revolutionize antimicrobial technology
High-resolution temperature profiling in the Pi Chamber: variability of statistical properties of temperature fluctuations
No full textThis study delves into the small-scale temperature structure inside the turbulent convection Pi Chamber under three temperature differences (10, 15, and 20 K) at Rayleigh number Ra ~ 10^9 and Prandtl number Pr = 0.7. We performed high-frequency measurements (2 kHz) with the UltraFast Thermometer (UFT) at selected points along the vertical axis. The miniaturized design of the sensor with a resistive platinum-coated tungsten wire, 2.5 μm thick and 3 mm long, mounted on a miniature wire probe, allowed for vertically undisturbed temperatureprofiling through the chamber’s depth spanning from 8 cm above the bottom to 5 cm below the top. The collected data, consisting of 19 and 3 min time series, were used to investigate the variability of the temperature field within the chamber, aiming to better address scientific questions related to its primary objective: understanding small-scale aerosol–cloud interactions. The analyses reveal substantial variability in both variance and skewness of temperature distributions near the top and bottom plates and in the bulk (central) region, which were linked to local thermal plume dynamics. We also identified three spectral regimes termed “inertial range” (slopes of ~ –7/5), “transition range” (slopes of ~ –3), and “dissipative range”, characterized by slopes of ~ –7. Furthermore, the analysis showed a power law relationship between the periodicity of large-scale circulation (LSC) and the temperature difference. Notably, the experimental results are in good agreement with direct numerical simulation (DNS) conducted under similar thermodynamic conditions, illustrating a comparative analysis of this nature
Denitrification processes, inhibitors, and their implications in ground improvement
Get PDFUreolysis and denitrification are the two major microbial metabolic pathways commonly used in Microbially induced calcite precipitation (MICP) for geoengineering applications. Although ureolysis is generally the more efficient pathway, the denitrification pathway has gained more attention recently because a diverse group of bacteria can precipitate calcite via denitrification, and no harmful byproduct is generated provided that the reduction of nitrate to nitrogen gas is complete. There are, however, many environmental factors that could inhibit or reduce the efficiency of the denitrification process in soil. Some examples of these factors include salinity, pH, temperature, biodiversity (abundance and species of denitrifiers and competitors), water stress (extreme wet-dry conditions), degree of saturation (anaerobic vs. aerobic conditions), high heavy metal content (e.g., mine tailings), and shortage of dissolved carbon sources. In this paper, the denitrification process, the denitrification inhibitors, and the mechanisms involved in their inhibition of the denitrification process are discussed in detail. This investigation indicates that although general optimum conditions can be formulated for MICP through denitrification, significant adjustments may be necessary if inhibitory conditions are anticipated. It was also shown that when inhibitors are expected, it is crucial to investigate not only the amount of precipitated calcium carbonate but also the N2O/N2 role= presentation style= box-sizing: border-box; margin: 0px; padding: 0px; display: inline-block; line-height: normal; font-size: 14.4px; font-size-adjust: none; word-spacing: normal; overflow-wrap: normal; text-wrap-mode: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; position: relative; \u3e2/2 gase ratio to ensure the complete reduction of nitrate to nitrogen gas and prevent the release of byproducts (especially N2O role= presentation style= box-sizing: border-box; margin: 0px; padding: 0px; display: inline-block; line-height: normal; font-size: 14.4px; font-size-adjust: none; word-spacing: normal; overflow-wrap: normal; text-wrap-mode: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; position: relative; \u3e2) into the environment. Finally, the implications of the inhibitory factors on the field application of denitrification MICP treatment for different geotechnical projects are discussed
Are there problems with academic problems? Examining problem types in two statics engineering textbooks
No full textA common distinction in engineering problems is classifying them as well-structured or ill-structured. It is assumed that classroom problems are well-structured while workplace problems are ill-structured. However, we cannot find empirical data to confirm or deny the claim that the bulk of classroom problems are well-structured. This research characterised 3,387 end-of-chapter problems presented in two engineering statics textbooks. Our data revealed that 99% of all problems were algorithmic, requiring a solution that was either numeric or an expression 92% of the time. Additionally, our analysis of pictorial representations (useful for cognitive scaffolding) revealed mixed results: while modeling was frequently used and beneficial, affordances were inconsistently applied, and embodiments were rarely employed. Even in foundational statics courses, students could benefit from exposure to a greater variety of problem types and cognitive scaffolding, providing students with opportunities to become more familiar with and better prepared for the nature of workforce problems
Anachronisms in the History of Mathematics: Essays on the Historical Interpretation of Mathematical Texts Edited by Niccolò Guicciardini
No full textSearch for a diffuse flux of photons with energies above tens of PeV at the Pierre Auger Observatory
Get PDFDiffuse photons of energy above 0.1 PeV, produced through the interactions between cosmic rays and either interstellar matter or background radiation fields, are powerful tracers of the distribution of cosmic rays in the Galaxy. Furthermore, the measurement of a diffuse photon flux would be an important probe to test models of super-heavy dark matter decaying into gamma-rays. In this work, we search for a diffuse photon flux in the energy range between 50 PeV and 200 PeV using data from the Pierre Auger Observatory. For the first time, we combine the air-shower measurements from a 2 km2 surface array consisting of 19 water-Cherenkov surface detectors, spaced at 433 m, with the muon measurements from an array of buried scintillators placed in the same area. Using 15 months of data, collected while the array was still under construction, we derive upper limits to the integral photon flux ranging from 13.3 to 13.8 km-2 sr-1 yr-1 above tens of PeV. We extend the Pierre Auger Observatory photon search program towards lower energies, covering more than three decades of cosmic-ray energy. This work lays the foundation for future diffuse photon searches: with the data from the next 10 years of operation of the Observatory, this limit is expected to improve by a factor of ∼20
Understanding coalitions\u27 emotion-belief expressions and rural identity: An ACF study of Colorado\u27s “MeatOut”
No full textOver the past decade, the United States has experienced increasing political polarization and populism, often aligned with rural-urban divides. A notable example emerged in 2021, when Colorado Governor Jared Polis issued a proclamation declaring March 20th, 2021 as MeatOut Day, encouraging residents to abstain from eating meat for that day. This initiative sparked significant backlash from rural communities against the Denver-based Governor, resulting in an emotionally charged discourse between opposing groups. This study employs the Advocacy Coalition Framework to analyze this conflict, examining two key questions: How do coalitions, defined by rural-urban divisions, express emotions and beliefs in a policy conflict, and how do the attributes of these coalitions differ? The findings reveal that in policy conflicts that implicate rural life, distinct coalitions form along rural-urban divides, each characterized by unique emotional-belief expressions. The study identifies a “rural effect,” characterized by deep core beliefs rooted in rural identity and negative emotions, while urban actors\u27 policy discourse primarily draws upon policy core beliefs and positive emotions