Advances in simulation technology have brought about many improvements to the way we train tasks, as well as how we perform tasks in the operational field. Augmented reality (AR) is an example of how to enhance the user's experience in the real world with computer generated information and graphics. Visual search tasks are known to be capacity demanding and therefore may be improved by training in an AR environment. During the experimental task, participants searched for enemies (while cued from visual, auditory, tactile, combinations of two, or all three modality cues) and tried to shoot them while avoiding shooting the civilians (fratricide) for two 2-minute low-workload scenarios, and two 2-minute high-workload scenarios. The results showed significant benefits of attentional cuing on visual search task performance as revealed by benefits in reaction time and accuracy from the presence of the haptic cues and auditory cues when displayed alone and the combination of the visual and haptic cues together. Fratricide occurrence was shown to be amplified by the presence of the audio cues. The two levels of workload produced differences within individual's task performance for accuracy and reaction time. Accuracy and reaction time were significantly better with the medium cues than all the others and the control condition during low workload and marginally better during high workload. Cue specificity resulted in a non-linear function in terms of performance in the low workload condition. These results are in support of Posner's (1978) theory that, in general, cueing can benefit locating targets in the environment by aligning the attentional system with the visual input pathways. The cue modality does not have to match the target modality. This research is relevant to potential applications of AR technology. Furthermore, the results identify and describe perceptual and/or cognitive issues with the use of displaying computer generated augmented objects and information overlaid upon the real world. The results also serve as a basis for providing a variety of training and design recommendations to direct attention during military operations. Such recommendations include cueing the Soldier to the location of hazards, and mitigating the effects of stress and workload.

The current dismounted soldier and the soldier of the future will be "loaded" with more information processing tasks while they perform shooting tasks. It is conceivable that some increased level of cognitive tasking may be performed simultaneously with required shooting tasks. The effect of cognitive load on shooting performance has been previously examined (Scribner and Harper, 2001). This study concentrated on the effect of various cognitive workload demands on a friend-foe discrimination shooting task in a single- and dual-task scenario. In light of this, it is imperative that the soldier not be overburdened mentally, which may result in decreased survivability and lethality. Specifically, this study was designed to examine the ability of the soldier to perform friend-foe target discrimination and shooting accuracy, with varying target exposure times, friendly target signatures, and varying cognitive load demands (working memory recall task). Using the Small Arms Simulator Testbed (SAST) we examined the effects of manipulations of working memory load and sustained information transfer, on shooting performance (as measured by target acquisition and friend/foe discrimination indices). Additionally, we investigated subjective measures of workload and stress. A secondary task, administered aurally, was given to subjects to attend to while they performed shooting (friend/foe discrimination task) scenarios: working memory recall task. Each type of task consisted of three levels of difficulty. Analysis of variance revealed significant differences for the memory recall task during shooting and non-shooting conditions. Furthermore, results showed that workload increased as a function of task demand, with associated decreases in shooting performance.

As the beneficial aspects of computers become more apparent to the elderly population and the baby boom generation moves into later adulthood there is opportunity to increase performance for older computer users. Performance decrements that occur naturally to the motor skills of older adults have shown to have a negative effect on interactions with indirect-manipulation devices, such as computer mice (Murata & Iwase, 2005). Although, a mouse will always have the traits of an indirect-manipulation interaction, the inclusion of additional sensory feedback likely increases the saliency of the task to the real world resulting in increases in performance (Biocca et al., 2002). There is strong evidence for a bimodal advantage that is present in people of all ages; additionally there is also very strong evidence that older adults are a group that uses extra sensory information to increase their everyday interactions with the environment (Cienkowski & Carney, 2002; Thompson & Malloy, 2004). This study examined the effects of having multimodal feedback (i.e., visual cues, auditory cues, and tactile cues) present during a target acquisition mouse task for young, middle-aged, and older experienced computer users. This research examined the performance and subjective attitudes when performing a mouse based pointing task when different combinations of the modalities were present. The inclusion of audio or tactile cues during the task had the largest positive effect on performance, resulting in significantly quicker task completion for all of the computer users. The presence of audio or tactile cues increased performance for all of the age groups; however the performance of the older adults tended to be positively influenced more than the other age groups due the inclusion of these modalities. Additionally, the presence of visual cues did not have as strong of an effect on overall performance in comparison to the other modalities. Although the presence of audio and tactile feedback both increased performance there was evidence of a speed accuracy trade-off. Both the audio and tactile conditions resulted in a significantly higher number of misses in comparison to having no additional cues or visual cues present. So, while the presence of audio and tactile feedback improved the speed at which the task could be completed this occurred due to a sacrifice in accuracy. Additionally, this study shows strong evidence that audio and tactile cues are undesirable to computer users. The findings of this research are important to consider prior to adding extra sensory modalities to any type of user interface. The idea that additional feedback is always better may not always hold true if the feedback is found to be distracting, annoying, or negatively affects accuracy, as was found in this study with audio and tactile cues.

The purpose of this study is to determine under what conditions multiple minimally intrusive physiological sensors can be used together and validly applied for use in areas which rely on adaptive systems including adaptive automation and augmented cognition. Specifically, this dissertation investigated the physiological transitions of operator state caused by changes in the level of taskload. Three questions were evaluated including (1) Do differences exist between physiological indicators when examined between levels of difficulty? (2) Are differences of physiological indicators (which may exist) between difficulty levels affected by spatial ability? (3) Which physiological indicators (if any) account for variation in performance on a spatial task with varying difficulty levels? The Modular Cognitive State Gauge model was presented and used to determine which basic physiological sensors (EEG, ECG, EDR and eye-tracking) could validly assess changes in the utilization of two-dimensional spatial resources required to perform a spatial ability dependent task. Thirty-six volunteers (20 female, 16 male) wore minimally invasive physiological sensing devices while executing a challenging computer based puzzle task. Specifically, participants were tested with two measures of spatial ability, received training, a practice session, an experimental trial and completed a subjective workload survey. The results of this experiment confirmed that participants with low spatial ability reported higher subjective workload and performed poorer when compared to those with high spatial ability. Additionally, there were significant changes for a majority of the physiological indicators between two difficulty levels and most importantly three measures (EEG, ECG and eye-tracking) were shown to account for variability in performance on the spatial task.

Requirements tracing is crucial for software engineering practices including change analysis, regression testing, and reverse engineering. The requirements tracing process produces a requirements traceability matrix(TM) which links high- and low-level document elements. Manually generating a TM is laborious, time consuming, and error-prone. Due to these challenges TMs are often neglected. Automated information retrieval(IR) techniques are used with some efficiency. However, in mission- or safety-critical systems a human analyst is required to vet the candidate TM. This introduces semi-automated requirements tracing, where IR methods present a candidate TM and a human analyst validates it, producing a final TM. In semi-automated tracing the focus becomes the quality of the final TM. This thesis expands upon the research of Cuddeback et al. by examining how human analysts interact with candidate TMs. We conduct two experiments, one using an automated tracing tool and the other using manual validation. We conduct formal statistical analysis to determine the key factors impacting the analyst’s tracing performance. Additionally, we conduct a pilot study investigating how analysts interact with TMs generated by automated IR methods. Our research statistically confirms the finding of Cuddeback et al. that the strongest impact on analyst performance is the initial TM quality. Finally we show evidence that applying local filters to IR results produce the best candidate TMs.

The role of a software engineer is often misconceived as an isolated task, needing nointerpersonal communication skills. Contrary to this perception there is a growingrecognition of the importance of soft skills in the field, with a lot of research, includingthis paper, pointing at the importance of the human factors.This thesis aims to highlight the significance of soft skills, specifically social skillssuch as communication, in the field of software engineering. It continues exploringthe impact on factors such as team performance and productivity.The research was conducted in two parts, with an initial literature study in orderto enhance the following parts. A survey distributed to industry professionals andvarious social media sites. The survey was then supplemented by five semi-structuredinterviews with both developers and managers in the field, allowing for more nuancedand detailed answers.The study shows the necessity of human factors, such as social skills and respectin successful software engineering practices. In software engineering teamwork isinherent, thus having qualities contributing to good team work is key. Notably, thestudy’s results indicate the importance of effective communication and a positivework environment for successful team work. However, the findings do not show acorrelation between a team’s social dynamics and its productivity, provided thatessential work communication is maintained in both high and low social interactionteams.The findings of this research can benefit both individuals striving to improveas software engineers, as well as companies seeking to improve team performance.A deeper understanding of the importance of soft skills can enable the formation ofmore effective, cohesive teams. More significantly, it could contribute to an improvedquality of life for software engineers, as interpersonal relations and communicationskills are key focal points in while working as a software engineer.

Frequent and effective design evaluation is foundational to the success of any product development effort. Products used, installed, or otherwise handled by humans would benefit from an evaluation of the product while formally considering both the physical embodiment of the technology, termed technology, and the steps a user should take to use that technology, termed tactics. Formal and simultaneous evaluations of both technology and tactics are not widespread in the product design literature. Although informal evaluation methods have advantages, formal methods are also known to be effective. In this paper we propose a formal method for evaluating tactics and technology simultaneously. Unlike the published literature, this evaluation involves explicitly defined tactics in the form of a written description of the actor, environment, and series of steps. It also involves the use of stage-appropriate, explicitly defined tactics-dependent criteria, which include criteria from a broad range of impact categories, such as impacts on the user, environment, project, and technology.

Previous research has highlighted key taxonomic factors that have been found to influence human performance on vigilance tasks. However, previous literature has focused on research conducted in laboratory settings but has not examined vigilance tasks in remote environments. The present dissertation addresses this gap in the literature by examining human performance on a remote vigilance task, as well as workload and stress associated with the task. Qualitative data were collected to further understand the environment and distractions that participants experienced. Across three experiments, 372 participants were asked to complete a vigilance task and answer surveys pertaining to stress, workload, and ambient distractions. Experiment one manipulated the taxonomic factors of event rate and signal discrimination. Next, experiment two manipulated the taxonomic factors of event rate and source complexity. Finally, experiment three manipulated the taxonomic factors of event rate and task type. Across all three experiments, results identified significant differences in performance for the low and high event rate conditions, which are consistent with previous findings. Furthermore, signal discrimination type, source complexity, and task type (i.e., sensory vs. cognitive) resulted in significant differences between groups on measures of performance. All three experiments reported changes in perceived stress and increases in perceived workload. Ambient distractions, when they occurred, did impact performance, but only for experiment two. Overall, this study provides further support for several facets of the vigilance taxonomy and attempts to understand the impact of remote environments and ambient distractions on vigilance performance. Thus, these findings are advancing our understanding of the vigilance taxonomy and how environmental effects may influence human performance.

Past research has shown that there is a relationship between body posture and cognitive processes. However, postures used with technological devices has not been studied more extensively. The purpose of this study was to examine posture effects when using a mobile device on interpretation bias, mood, and physical tension. Each participant was randomly assigned one of three conditions: sitting slumped, sitting upright, or lying down. Participants were asked to complete the Scrambled Sentences Task (SST), a task of unscrambling emotional and neutral sentences, to measure their interpretation bias. Additional questions were asked to measure the participant's physical tension and mood. Results suggested no significant differences in interpretation bias depending on posture. There was no significant difference in the performance of unscrambling emotional sentences compared to neutral ones for sitting slumped and sitting upright. When lying down, participants unscrambled fewer neutral sentences compared to emotional ones. Physical tension was found to be a mediator for the relationship between posture (slumped and upright) and mood. The results of this study provide insight of possible confounding variables influencing the relationship between posture and mood.It additionally showed that emotional content is processed differently compared to neutral content when lying down. Further research is needed to understand how physical tension caused by posture being altered when using mobile device affects psychological well-being.

The present study empirically examined the effects of four fatiguing task domains on executive function through participants' reaction time, accuracy, and brain activity in prefrontal cortex (PFC). Forty college-age participants were collected (16 males and 24 females), of which eleven were examined using a functional near-infrared spectroscopy (fNIRS) imaging system. The present study used a 4×2 mixed factorial design consisting of fatiguing task (arm contractions task, vigilance task, distance-manipulated Fitts' task, size-manipulated Fitts' task) as a between-participant variable and n-back testing period (pre-test versus post-test 3-back task) as a within-participant variable. Results indicated significant increases in 3-back performance after the fatiguing tasks, and significant increases in 3-back compensatory brain activity in dorsomedial and dorsolateral prefrontal cortex (dmPFC and dlPFC) after the fatiguing tasks. Furthermore, results showed an interaction between 3-back target type and fatiguing task on standardized changes in reaction time, and an interaction between fatiguing task and testing period on brain activity in dmPFC. Theoretical and practical implications are discussed. Findings from this study may be used to help draw the boundaries on different domains of fatigue and their effects on the brain and body.