This work focuses on the analysis of pilots’ performance during manual flight operations in different stages of training and their influence on gaze strategy. The secure and safe operation of air traffic is highly dependent on the individual performances of the pilots. Before becoming a pilot, he/she has to acquire a broad set of skills by training to pass all the necessary qualification and licensing standards. A basic skill for every pilot is manual control operations, which is a closed-loop control process with several cross-coupled variables. Even with increased automation in the cockpit, the manual control operations are essential for every pilot as a last resort in the event of automation failure. A key element in the analysis of manual flight operations is the development over time in relation to performance and visual perception. An experiment with 28 participants (including 11 certified pilots) was conducted in a Boeing 737 simulator. For defined flight phases, the dynamic time warping method was applied to evaluate the performance for selected criteria, and eye-tracking methodology was utilized to analyze the gaze-pattern development. The manipulation of workload and individual experience influences the performance and the gaze pattern at the same time. Findings suggest that the increase of workload has an increased influence on pilots depending on the flight phase. Gaze patterns from experienced pilots provide insights into the training requirements of both novices and experts. The connection between workload, performance and gaze pattern is complex and needs to be analyzed under as many differing conditions. The results imply the necessity to evaluate manual flight operations with respect to more flight phases and a detailed selection of performance indications.
High-alumina containing high-level waste (HLW) will be vitrified at the Waste Treatment Plant at the Hanford Site. The resulting glasses, high in alumina, will have distinct composition-structure-property (C-S-P) relationships compared to previously studied HLW glasses. These C-S-P relationships determine the processability and product durability of glasses and therefore must be understood. The main purpose of this study is to understand the detailed structural changes caused by Al:Si and (Al + Na):Si substitutions in a simplified nuclear waste model glass (ISG, international simple glass) by combining experimental structural characterizations and molecular dynamics (MD) simulations. The structures of these two series of glasses were characterized by neutron total scattering and 27Al, 23Na, 29Si, and 11B solid-state nuclear magnetic resonance (NMR) spectroscopy. Additionally, MD simulations were used to generate atomistic structural models of the borosilicate glasses and simulation results were validated by the experimental structural data. Short-range (eg, bond distance, coordination number, etc) and medium-range (eg, oxygen speciation, network connectivity, polyhedral linkages) structural features of the borosilicate glasses were systematically investigated as a function of the degree of substitution. The results show that bond distance and coordination number of the cation-oxygen pairs are relatively insensitive to Al:Si and (Al + Na):Si substitutions with the exception of the B-O pair. Additionally, the Al:Si substitution results in an increase in tri-bridging oxygen species, whereas (Al + Na):Si substitution creates nonbridging oxygen species. Charge compensator preferences were found for Si-[NBO] (Na+), [3]B-[NBO] (Na+), [4]B (mostly Ca2+), [4]Al (nearly equally split Na+ and Ca2+), and [6]Zr (mostly Ca2+). The network former-BO-network former linkages preferences were also tabulated; Si-O-Al and Al-O-Al were preferred at the expense of lower Si-O-[3]B and [3]B-O-[3]B linkages. These results provide insights on the structural origins of property changes such as glass-transition temperature caused by the substitutions, providing a basis for future improvements of theoretical and computer simulation models. 相似文献
Today’s time-of-flight (TOF) sensors measure full-range distance information by estimating the elapsed time between emission and receiving of active light in real-time. Such sensors are inexpensive, compact, and they have a high performance, which especially fits real-time applications, e.g. in the fields of automotive, robotics, 3D imaging, and visualization. The simulation of such sensors is an essential building block for hardware design and application development. Therefore, the simulation data must capture the major sensor characteristics.This paper introduces a simulation approach, which is motivated by physics, for the Photonic Mixing Device (PMD) sensor which is a specific type of time-of-flight sensor. Dynamic motion blurring and resolution artifacts such as flying pixels as well as the typical deviation error are prominent effects of real world systems. Flying pixels arise when an area of inhomogeneous depth is covered by a single PMD-pixel whereas the deviation error is based on the anharmonic properties of the optical signal. The modeling of these artifacts is essential for an authentic simulation approach. We present a detailed comparison between a real PMD-device and the simulation data regarding the sensor characteristics.The proposed algorithms are implemented in a hardware accelerated solution which makes use of the programmability of modern Graphics Processing Units (GPUs). This way, an interactive simulation feedback is provided for applications and further data processing. The simulation takes place in real-time and thus all required control mechanisms are accessible in real-time, too. 相似文献
Many sophisticated techniques for the visualization of volumetric data such as medical data have been published. While existing techniques are mature from a technical point of view, managing the complexity of visual parameters is still difficult for non-expert users. To this end, this paper presents new ideas to facilitate the specification of optical properties for direct volume rendering. We introduce an additional level of abstraction for parametric models of transfer functions. The proposed framework allows visualization experts to design high-level transfer function models which can intuitively be used by non-expert users. The results are user interfaces which provide semantic information for specialized visualization problems. The proposed method is based on principal component analysis as well as on concepts borrowed from computer animation. 相似文献
The rapid increase of renewable energy sources made coordinated control of the distributed and intermittent generation units a more demanded task. Matching demand and supply is particularly challenging in islanded microgrids. In this study, we have demonstrated a mixed‐integer quadratic programming (MIQP) method to achieve efficient use of sources within an islanded microgrid. A unique objective function involving fuel consumption of diesel generator, degradation in a lithium‐ion battery energy storage system, carbon emissions, load shifting, and curtailment of the renewable sources is constructed, and an optimal operating point is pursued using the MIQP approach. A systematic and extensive methodology for building the objective function is given in a sequential and explicit manner with an emphasis on a novel model‐based battery aging formulation. Performance of the designed system and a sensitivity analysis of resulting battery dispatch, diesel generator usage, and storage aging against a range of optimization parameters are presented by considering real‐world specifications of the Semakau Island, an island in the vicinity of Singapore. 相似文献
Retail banking has undergone a massive transformation in the last few years. A major aspect is changing consumer behavior. The aim of the paper is to better understand retail banking consumers regarding the impact of digitalization. Consequently, we acquired online consumer review data from Germany, the UK and US. We analyzed the data using coding techniques of grounded theory, supported by interdisciplinary literature to identify and categorize the relevant influence factors. The outcome of the paper is an integrated model of consumer decision-making in today’s retail banking along with four detailed partial models of the respective decision stages. 相似文献
The use of patterned media is a new approach proposed to extend the recording densities of hard disk drives beyond 1 Tb/in.2. Bit-patterned media (BPM) overcome the thermal stability problems of conventional media by using single-domain islands for
each bit of recorded information, thereby eliminating the magnetic transition noise (Albrecht et al., Magnetic Recording on
Patterned Media, 2003). Considering steady state conditions, we have transferred the pattern from the disk surface onto the
slider surface and have investigated the pressure generation due to the bit pattern. To reduce the numerical complexity, we
have generated the bit pattern only in the areas of the slider near the trailing edge, where the spacing is small. Cylindrical
protrusions were modeled using very small mesh size on the order of nanometers to obtain the flying characteristics for the
entire slider air bearing surface (ABS) using the “CMRR” finite element Reynolds equation simulator (Duwensee et al., Microsyst
Technol, 2006; Wahl et al., STLE Tribol Trans, 39(1), 1996). The effect of pattern height, pattern diameter, slider skew angle,
and slider pitch angle on flying height of a typical slider is investigated. Numerical results show that the flying height
decreases for a patterned slider and the change in flying height is a function of the pattern height and ratio of the pattern
diameter to the pattern pitch. In comparison to discrete track media, the flying height loss is larger for a patterned slider
disk interface for the same recessed area of pattern. 相似文献