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Screening Smoke Compositions
Published in Ajoy K. Bose, Military Pyrotechnics, 2021
Visibility is related to the distance which a viewer can identify any object relative to the background and illumination. Attenuation (obscuration plus scattering plus reflection etc.) is the phenomenon causing degradation of the visibility. A battlefield requires that the enemy should not be successful in locating the position of the personnel and the firing tanks, equipment, trucks and other battlefield-related inventories. The options available for degrading visibility are:Hiding like concealing behind the treeBlending with nature like covering the truck with nets and tree branches and leaves, etc.Disguising
Motion Planning: Recent Developments
Published in Shuzhi Sam Ge, Frank L. Lewis, Autonomous Mobile Robots, 2018
Héctor H. González-Baños, David Hsu, Jean-Claude Latombe
Sensor placement is related to the classic art gallery problem [47], which asks for the minimum number of guards whose joint visibility region covers the interior of an art gallery. In its simplest form, the problem considers the art gallery to be a polygonal environment. It also assumes a simple line-of-sight visibility model, where two points are visible to each other if the line segment between them is unobstructed. The problem seems deceptively simple, but finding the minimum number of guards is actually NP-hard. In robotics, the visibility model is rarely as clean as that assumed in the art gallery problem. So the art gallery results are usually not directly applicable.
Testing the Workplace Environment
Published in Samuel G. Charlton, Thomas G. O’Brien, Handbook of Human Factors Testing and Evaluation, 2019
Visibility measurements should be made for vehicles and for other items where the user must view through windows, port holes, periscopes, and so forth; visually acquire and recognize components of the item; read displays and labels mounted in or on the item; and use optical devices associated with the item. Some of the factors that influence visibility include field of view (unobstructed), distance to and orientation of components requiring visibility, and viewing media (e.g., fog, rain, clear air, glass). Visibility test procedures are found in TECOM’s TOP 1–2–610 (1983b).
An SEM-Neural Network Approach for Predicting Antecedents of Online Grocery Shopping Acceptance
Published in International Journal of Human–Computer Interaction, 2022
Ashish Kumar Singh, Francisco Liébana-Cabanillas
The visibility of a given technology stems from Rogers’ diffusion of innovation theory (2010) and refers to the degree to which future adopters can see it as an innovation. Visibility is the degree to which a system is observable or apparent in an organisation (Thong et al., 2002). The term “visibility” refers to a person’s perception of the amount to which their system is noticed by others (Fisher & Price, 1992). Other authors (Bearden & Rose, 1990; Fisher & Price, 1992) found that users’ perceptions of visibility varied greatly due to the type of good or service, utilisation circumstance, actual consequences, commodity interactions, and personality factors. Before TAM, studies found that visibility is separate from the constructs of image and norms (Fisher & Price, 1992; Venkatesh & Bala, 2008; Venkatesh & Davis, 2000). Despite that, a picture depicts a user’s perception of how technology improves social status (Moore & Benbasat, 1991).
Employing visibility and agent-based accessibility analysis to enhance social interactions in older adult care facilities
Published in Architectural Science Review, 2020
By understanding and predicting the effects of spatial design parameters to social experience in care facilities, designers can search for design solutions to improve the quality of older adult living with enhanced social interactions. Evaluating possible behaviours enacted in each design alternative enables designers to improve their design while being aware of the effects of their design decisions on levels of visibility and accessibility. The evaluation framework of this study has potential applications for care providers in future research. Studies on the effects of substantive design alternatives, such as spatial layout changes of patient rooms, social gathering spaces and courtyard locations, on visibility and accessibility will follow. Another hidden attribute impacting the possibility of social interactions may be aspects of time, such as the time of stay in corridors and lounge areas, but further empirical studies will be required.
Gait analysis and avoidance mechanism of pedestrians under the quantitative control of visibility
Published in Transportmetrica A: Transport Science, 2022
Shuchao Cao, Yang Li, Jie Ni, Xiaohui Wu
Generally, environment luminance, light transparency of the atmosphere and observation target are the most important external factors that affect the visibility condition. Therefore, we implement our method from the following three aspects. Firstly, the light entering the eyes from the outside needs to be controlled. Here a goggle where the light membrane with a certain transmittance is attached is designed, as shown in Figure 1. When an individual wears the goggle, the emergent light is controlled by changing the light transmittance (LT) of the membrane. Secondly, the environment’s luminance needs to be controlled properly. If the brightness of the environment is too high, it is difficult to obtain low visibility conditions even if the LT of the membrane is very low. However, if the environmental illumination is too low, pedestrian behaviour cannot be identified clearly due to the low quality of the experimental video. Furthermore, pedestrians’ trajectories are difficult to be extracted and quantitative analysis at the microscopic level cannot be performed under this circumstance. Here the environmental luminance is fixed to 55 lux (Illumination is measured by the GM1020 digital lux meter) through a series of tests in this study. Thirdly, the visual object also has a significant influence on the visibility evaluation. Here the direction indicator on the evacuation sign widely used in buildings is selected as the observation target. As displayed in Figure 2, the evacuation sign with a size of 33.5 cm × 14.5 cm is hung at a height of 155 cm close to the eye height of adults. Briefly, this method aims to obtain a series of visibility conditions under a certain environmental luminance by measuring the visible distance of pedestrians under different light transmittances.