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The decay dynamics of the α-group ( 2D →4S transition) of N atoms stabilized in the collection of N2–Ne nanoclusters were studied at a temperature of 1.3 K. The variation of the N2/Ne ratio in nanoclusters results in substantial changes in the luminescence spectra of the α-group and in the characteristic decay times for the components of these spectra. In all obtained α-group spectra, the narrow component at λ = 519.9 nm was observed. The spectroscopic results provide information about the structure of the nitrogen–neon nanoclusters. At elevated temperatures ( ≈ 15–36 K), enhanced oxygen β-group luminescence is observed in N2–Ne nanoclusters, with a smaller intensity enhancement than those observed within pure N2 and mixed N2–Kr nanoclusters. These results confirm the energy transfer mechanism, in which excited nitrogen molecules formed on the nanocluster surface transfer energy to the stabilized oxygen atoms through the chain of N2 molecules in a solid matrix. 

Entry guidance has played a vital role in planetary landing missions from the Apollo era to now. Modern techniques that directly utilize highly nonlinear entry dynamics, unlike the Apollo reentry guidance, are gaining attention. This study demonstrates that numerical predictor-corrector guidance can generate a trajectory that closely resembles the historic Apollo final reentry path. Secondly, it compares a conventional bank reversal algorithm with a prediction-based lateral guidance algorithm. Finally, the study proposes a predictive no-fly zone avoidance guidance algorithm that can effectively address geographic constraints for hypersonic gliding vehicles. 

The numerical predictor-corrector guidance method with a linear bank angle parameterization has been widely applied to various atmospheric entry guidance problems. However, it has been found that the linear bank angle approach has limitations in satisfying the final state requirement of a specific type of atmospheric entry mission. In response, this paper proposes a novel bank angle parameterization based on a logistic function, which improves the energy preservation capability and increases the potential final altitude at the end of the entry phase. The paper also suggests a guideline to determine a guidance law activation point for better entry performance. Numerical simulations demonstrate that the proposed guidance scheme outperforms the linear bank profile approach and is suitable for future human Mars landing missions. 

The X-ray absorption spectroscopy including Extended X ray Absorption Fine Structure (EXAFS) , X ray Absorption Near Edge Structure (XANES) and X-ray absorption near edge and pre edge feature is used to analyze the nature and concentration of iron in plants, spinach and parsley. Primary data was collected at Cornell High Energy Synchrotron Source. Data analyses were done by community college students. EXAFS data analysis process include edge normalization, background subtraction, transformation to k space from energy, Fourier transformation, back transform of selected peaks, and curve fitting to identify type and number of near neighbor atoms. X-ray absorption pre=edge feature, which appears as very small absorption peak before the main peak, is used to study ironoxygen bonding and asymmetry of iron compounds. Pre edge data analysis include extraction of the pre-edge from main absorption spectrum, normalization to main edge height, and Lorentzian fit to back ground subtracted data. X-ray absorption data from spinach and parsley, as well as several iron supplements and the soil of which plants were grown was analyzed. The preliminary data analysis pre edge feature yields two forms of iron in both plants. One form has oxygen as near neighbor atoms and the other without oxygen. 

The numerical predictor-corrector guidance with a bank angle parameterization has been employed in various entry examples where only a final range constraint is present. However, a future human Mars landing mission requires an accurate final location and a precise final altitude and velocity at the end of the entry trajectory. This paper proposes to use a quadratic bank parameterization to generate an entry trajectory that satisfies the multi-constraints. A solution space analysis confirms the numerical feasibility of the given entry problem. Monte Carlo simulation results demonstrate the potential applicability of the proposed method for future Human Mars landing missions. 

Habituation to signals that warn of a potential danger in high-risk work environments is a critical causal factor of workplace accidents. Such habituation is hard to measure in a real-world setting, and no existing intervention can effectively curb it. Here, we present a protocol to enhance workers’ sensory responses to frequently encountered warnings at workplaces using a virtual-reality-based behavioral intervention. We describe steps for performing a virtual reality experiment and an electroencephalography (EEG) experiment with human participants. 

The interaction between a pair of tandem in-line oscillating hydrofoils is presented. The hydrofoils undergo sinusoidal pitching about their leading edges with a fixed Strouhal number of [Formula: see text] and a Reynolds number of 10,000. The streamwise spacing, spanwise spacing, and phase offset between the hydrofoils are varied. Force measurements are employed to investigate changes in thrust, lift, spanwise force, power consumption, and propulsive efficiency. A method to mitigate confounding factors from connecting rod drag is employed using streamlined fairings. Near and far streamwise spacing regions are identified with a transition occurring near 0.875 chord lengths downstream. Decreasing streamwise spacing in the far region causes a rise in the maximum power consumption of the follower hydrofoil. Decreasing streamwise spacing in the near region results in an opposite trend, with a sharp drop in maximum average power consumption by the follower. An empirical model for power consumption of the follower is developed. Increased spanwise spacing is found to weaken the interaction between the hydrofoils, driving them toward their isolated performance. This phenomenon is related to the spanwise contraction of the wake shed by the leader and is a function of the overlap of the wake region impacting the follower.