A Puzzle about Knowing Conditionals

We present a puzzle about knowledge, probability and conditionals. We show that in certain cases some basic and plausible principles governing our reasoning come into conflict. In particular, we show that there is a simple argument that a person may be in a position to know a conditional the consequent of which has a low probability conditional on its antecedent, contra Adams’ Thesis. We suggest that the puzzle motivates a very strong restriction on the inference of a conditional from a disjunction

improving path planning of unmanned aerial vehicles in an immersive environment using meta-paths and terrain information

Effective command and control of unmanned aerial vehicles (UAVs) is an issue under investigation as the military pushes toward more automation and incorporation of technology into their operational strategy. UAVs require the intelligence to maneuver safely along a path to an intended target while avoiding obstacles such as other aircraft or enemy threats. To date, path-planning algorithms (designed to aid the operator in the control of semi-autonomous UAVs) have been limited to providing only a single solution (alternate path) without utilizing input or feedback from the UAV operator. The work presented in this thesis builds off of and improves an existing path planner. The original path planner presents a unique platform for decision making in a three-dimensional environment where multiple solution paths are generated using Particle Swarm Optimization (PSO) and returned to the operator for evaluation. The paths are optimized to minimize risk due to enemy threats, to minimize fuel consumption incurred by deviating from the original path, and to maximize reconnaissance over predefined targets. The work presented in this thesis focuses on improving the mathematical models of these objectives. Terrain data is also incorporated into the path planner to ensure that the generated alternate paths are feasible and at a safe height above ground. An effective interface is needed to evaluate the alternate paths returned by PSO. A meta-path is a new concept presented in this thesis to address this issue. Meta-paths allow an operator to explore paths in an efficient and organized manner by displaying multiple alternate paths as a single path cloud. The interface was augmented with more detailed information on these paths to allow the operator to make a more informed decision. Two other interaction techniques were investigated to allow the operator more interactive control over the results displayed by the path planner. Viewing the paths in an immersive environment enhances the operator\u27s understanding of the situation and the options while facilitating better decision making. The problem formulation and solution implementation are described along with the results from several simulated scenarios. Preliminary assessments using simulated scenarios show the usefulness of these features in improving command and control of UAVs. Finally, a user study was conducted to gauge how different visualization capabilities affect operator performance when using an interactive path planning tool. The study demonstrates that viewing alternate paths in 3D instead of 2D takes more time because the operator switches between multiple views of the paths but also suggests that 3D is better for allowing the operator to understand more complex situations

Utilization of LiDAR Technology to Assess Vertical Clearances of Civil Infrastructure

The issue of vertical clearances along highway systems impact the functionality of the road network. Extracting current routing clearances for each structure can be a challenging and hazardous task. Pavement changes and roadway rehabilitation projects can alter roadway geometry, complicating efforts to maintain accurate clearance databases. Vertical clearance measurements may vary from one lane to another beneath overhead structures and are often difficult to obtain due to high traffic volumes. Inherently, traditional methods that are used to obtain the measurements routinely impede the flow of traffic and subject workers to dangerous environments. This study will examine the use of a Mobile LiDAR system and its applicability and accuracy to obtain vertical clearances on bridge structures. Further, the study will investigate the impact of utilizing a Mobile LiDAR system on traffic disruption and worker safety. The measurements extracted from LiDAR point clouds are compared to measurements obtained from traditional techniques using a laser tape meter and total station. Results will be analyzed to assist in quantifying the potential error between field and LiDAR measurements. Furthermore, the impact on work zone safety and traffic disruption is investigated. The results obtained from this study can be used to help identify the most effective method to extract infrastructure clearances and aid in future assessments

Understanding Tourism at Heritage Religious Sites

unDersTanDing Tourism aT heriTage religious siTe

The Cross-Dressing Case for Bathroom Equality

While transgender rights advocates have won many battles in the fight for equality, bathroom discrimination remains a significant obstacle to transgender people’s full participation in society. This Article discusses the reasoning behind the cases that have rejected transgender people’s discrimination claims based on bathroom exclusion. The Article then demonstrates how these arguments mirror the rationales offered by supporters of long-dead, unconstitutional cross-dressing laws. Synthesizing the two bodies of case law, Levi and Redman offer a new way forward for transgender advocates seeking bathroom equality