Dahai Liu

Embry-Riddle Aeronautical University · Department of Human Factors and Systems

This study applied a backpropagation artificial neural network approach to investigate both the Human Factors Analysis and Classification System (HFACS)-related unsafe act tiers of factors and other non-HFACS factors in an attempt to recognize patterns for general aviation accident fatalities. Data were obtained from the HFACS database and extracte...

The effect of adaptive display on pilot performance was assessed using objective and subjective measures from a sequence of 2 experiments. Combat aircraft advances have led to dramatic increases in the operational tempo facing the pilot, increasing the likelihood for situation awareness (SA) failures, biases, and information overload. Prior researc...

Advances in aircraft operational capabilities have led to a dramatic increase in the operational tempo facing air combat aviators, which has in turn led to SA failures, particularly with respect to secondary information. For example, when engaging an air threat, aviators will often overlook key information such as geopolitical boundaries, resulting...

This study investigated the effects of synthetic vision system (SVS) concepts and advanced flight controls on the performance of pilots flying a light, single-engine general-aviation airplane. We evaluated the effects and interactions of 2 levels of terrain portrayal, guidance symbology, and flight control response type on pilot performance during...

It has been documented that the military intends to increase the number of Unmanned Aerial Vehicles (UAVs) in service while at the same time reducing the number of operators (Dixon et al. 2004). To meet this demand, many of the current UAV operator function will need to be automated. Levels of automation exist along a continuum from fully manual to...

The present study explored how individuals perceive actions in gaming that contain ethical components, whether they have ever engaged in those behaviors and how judgments of ethical actions in gaming relate to participant personality. Participants completed a 16-item survey, which measured their perception of the ethics of gaming behaviors, such as...

Autonomous unmanned aircraft systems (UAS) are being utilized at an increasing rate for a number of military applications. The role of a human operator differs from that of a pilot in a manned aircraft, and this new role creates a need for a shift in interface and task design in order to take advantage of the full potential of these systems. This s...

This study used queuing networks and discrete event simulation (DES) to investigate the effects of baggage volume and alarm rate at the security screening checkpoint (SSCP) of a small origin and destination airport. A queuing network was applied for theoretical modeling of the SSCP performance, and a DES model using Arena Version 12 was used for an...

Humans are remarkably complex and unpredictable; however, while predicting human behavior can be problematic, there are methods such as modeling and simulation that can be used to predict probable futures of human decisions. The present study analyzes the possibility of replacing human subjects with data resulting from pure models. Decisions made b...

A series of 50 responses regarding reasons for cheating behavior in video games were provided by undergraduate students. These responses were sorted into a series of 13 categories by raters to investigate the most common reasons provided for cheating. An analysis of inter-rater agreement as well as frequency of category representation is provided....

We conducted this study to investigate the effect of smart parking systems on parking search times in large parking lots. Smart parking systems are systems that provide real-time parking spot availability information to drivers. We used discrete event simulation to model a university parking lot and estimate how much time could be saved without phy...

Vehicle collisions amount to a significant loss of life in America. Upward of 30,000 lives are lost each year in the United States alone. Hundreds of millions of dollars are spent each year on vehicle safety and roadway design in the United States, and many studies have been conducted on the causal factors for vehicle collisions. This study used ar...

This study examined the effects of system reliability and task uncertainty on unmanned aerial vehicle (UAV) operator performance for the patrol and target recognition tasks. The primary task was image processing that entailed differentiating between targets and distracters, making necessary changes to the identifications provided by the automation,...

Interface designs native to handheld control and feedback devices (e.g., smartphones and tablets) are becoming more accessible within the small unmanned aerial system (sUAS) community due to increased usage in remote control (R/C) model aircraft platforms [33], improved processing to cost [4], and increased interoperability supporting custom develo...

This study presented a resource scheduling model of the Flight Training Department at Embry Riddle Aeronautical University's Daytona Beach Campus built using Discrete Event Simulation, to assess the effect of changes in the resources available to students in Flight Training Device (FTD) course modules on Flight Training effectiveness. Historical da...

The control of an aircraft relies on sensory feedback. It follows that any aspect that could create a situation where that feedback is faulty can lead to unintended outcomes. The size of very large jet aircraft can result in kinematic effects that impact the perceptions of the flight crew. Due to the large amount of inertia involved, coupled with a...

This study utilized the discrete-event simulation (DES) approach to optimize the daily tutor cost for the Unified Tutoring Center, located at the Daytona Beach campus of Embry-Riddle Aeronautical University. The simulation model was built using Arena version 12, and the objective of the study was to determine an optimum tutor staffing schedule to r...

The demand for Unmanned Aircraft Systems (UASs) capabilities is rapidly increasing in the civilian sector. UAS operations, however, will not be carried out in the National Airspace System until safety concerns are alleviated. Among these concerns is determining the appropriate level of automation in conjunction with a suitable pilot who exhibits th...

This study used a logistic regression model to investigate the relationship between several predicting factors and burglary occurrence probability with regard to the epicenter. These factors include day of the week, time of the day, repeated victimization, connectors and barriers. Data was collected from a local police report on 2010 burglary incid...

Research related to game-based and technology-enhanced learning lacks a focused experimental method. The present paper articulates a well-defined experimental method for studying game-based learning from pre-learning interventions to post-testing assessment of retention and transfer.

We propose to model learning of optimal decision rules using a mathematically rigorous descriptive model given by a modified set of Cohen-Grossberg neural network equations with reaction-diffusion processes in an environment of uncertainty. Our theory, which we call Neurohydrodynamics, naturally arises within the framework of neural networks while...

Vehicle collisions amount to a significant loss of life in America. This study used artificial neural networks as a means to predict the occurrence of injury of a vehicle collision. Using Neural Ware’s Predict software a neural network structure was trained, tested, and validated using data from the 2006 and 2007 Florida Traffic Crash Database. The...

Systems engineering plays a vital role in project and production development. The complete life cycle of a project incorporates systems engineering throughout. Systems are involved from the beginning, involving the conceptual design and planning processes, to the very end with testing procedures and production finalization. The topic involves subje...

The effect of testing location on usability test elements such as stress levels and user experience is not clear. A comparison between traditional lab testing and synchronous remote testing was conducted. The present study investigated two groups of users in remote and traditional settings. Within each group participants completed two tasks, a simp...

The demands for Unmanned Vehicles are rapidly increasing in the civilian sector. However, operations will not be carried out in the National Air Space (NAS) until safety concerns are alleviated. Among these concerns is determining the appropriate level of automation in conjunction with a suitable pilot who exhibits the necessary knowledge, skills,...

It is very important that designers recognize the benefits and limitations of different usability inspection methods. This is because the quality of the usability evaluation is dependent on the method used. Two of the most popular usability evaluation techniques are user testing and heuristic analysis. The main objective of this study was to compar...

Commercial aviation and the military have long reaped the rewards provided by the use of flight simulation to train pilots. Using simulators for training maximizes the use of operational systems for revenue producing activities, and minimizes the use of operational systems for non-revenue producing activities such as training. It also eliminates th...

Historically, the aviation industry expends significant amounts of time and resources training and retraining its workforce to perform psychomotor and cognitive maintenance tasks necessary to keep aircraft safely flying (Ott, 1995). The industry continues to dedicate a substantial amount of its effort and capital ensuring that its workforce is prep...

Existing research on human skills acquisition studies has shown that learning follows a non-linear pattern, but the exact form remains unknown due to the limitation of traditional experimental methods and lack of systematic modeling of tasks. We applied a non-linear fractal analysis on the time series data produced by human subjects on target-track...

Continuous quality improvement through process refinement is a must for survival of all industries in the contemporary market place. This is true for both manufacturing and service sectors. While manufacturing has spearheaded quality efforts, the service sector has lagged behind primarily because of inherent difficulties. Customer satisfaction is p...

Inspired by De Broglie's pilot wave interpretation of Quantum Mechanics and the subsequent development of Bohm's Quantum Hydrodynamics, we propose a model for the dynamics of a neural network with reaction-diffusion processes described by a modified set of Cohen-Grossberg equations, which we call Neurohydrodynamics. In this approach, a pilot wave i...