Consistent numerical methods for state and control constrained trajectory optimisation with parameter dependency

The article of record as published may be found at https://doi.org/10.1080/00207179.2020.1717633This paper describes and proves the consistency of a flexible numerical method for producing solutions to state and control constrained control problems with parameter dependencies. This method allows for the use of a variety of underlying discretisation schemes, which can be catered to differing numerical chal- lenges of specific problems, such as rapid convergence or large parameter spaces. The paper first provides a broad formulation for optimal control problems with parameter dependencies which includes multiple types of state, control, and end time constraints to enable a wide scope of application. For this formula- tion, the consistency of these methods for state and control constrained problems is then proved. Finally, a numerical example of an optimal search problem with constraints is demonstrated.This work was supported by Office of Naval Research [N001415WX01451, N001417WX01098, N001418WX01204].This work was supported by Office of Naval Research [N001415WX01451, N001417WX01098, N001418WX01204]

Modeling and Control of Large-Scale Adversarial Swarm Engagements

We theoretically and numerically study the problem of optimal control of large-scale autonomous systems under explicitly adversarial conditions, including probabilistic destruction of agents during the simulation. Large-scale autonomous systems often include an adver sarial component, where different agents or groups of agents explicitly compete with one another. An important component of these systems that is not included in current theory or modeling frameworks is random destruction of agents in time. In this case, the modeling and optimal control framework should consider the attrition of agents as well as their position. We propose and test three numerical modeling schemes, where survival probabilities of all agents are smoothly and continuously decreased in time, based on the relative positions of all agents during the simulation. In particular, we apply these schemes to the case of agents defending a high-value unit from an attacking swarm. We show that these models can be successfully used to model this situation, provided that attrition and spatial dynamics are coupled. Our results have relevance to an entire class of adversarial autonomy situations, where the positions of agents and their survival probabilities are both important.ONR SoA programNPS CRUSER progra

Bernstein Polynomial-Based Method for Solving Optimal Trajectory Generation Problems

The article of record as published may be found at http://dx.doi.org/10.3390/s22051869This paper presents a method for the generation of trajectories for autonomous system operations. The proposed method is based on the use of Bernstein polynomial approximations to transcribe infinite dimensional optimization problems into nonlinear programming problems. These, in turn, can be solved using off-the-shelf optimization solvers. The main motivation for this approach is that Bernstein polynomials possess favorable geometric properties and yield computationally efficient algorithms that enable a trajectory planner to efficiently evaluate and enforce constraints along the vehicles� trajectories, including maximum speed and angular rates as well as minimum distance between trajectories and between the vehicles and obstacles. By virtue of these properties and algorithms, feasibility and safety constraints typically imposed on autonomous vehicle operations can be enforced and guaranteed independently of the order of the polynomials. To support the use of the proposed method we introduce BeBOT (Bernstein/B�zier Optimal Trajectories), an open-source toolbox that implements the operations and algorithms for Bernstein polynomials. We show that BeBOT can be used to efficiently generate feasible and collision-free trajectories for single and multiple vehicles, and can be deployed for real-time safety critical applications in complex environments.This research was supported by the Office of Naval Research, grants N000141912106, N000142112091 and N0001419WX00155. Antonio Pascoal was supported by H2020-EU.1.2.2-FET Proactive RAMONES, under Grant GA 101017808 and LARSyS-FCT under Grant UIDB/50009/2020. Isaac Kaminer was supported by the Office of Naval Research grant N0001421WX01974.This research was supported by the Office of Naval Research, grants N000141912106, N000142112091 and N0001419WX00155. Antonio Pascoal was supported by H2020-EU.1.2.2-FET Proactive RAMONES, under Grant GA 101017808 and LARSyS-FCT under Grant UIDB/50009/2020. Isaac Kaminer was supported by the Office of Naval Research grant N0001421WX01974

Representation of Aging Women in Fashion and Non-fashion Advertisements

The purpose of this study was to investigate how older women are represented in fashion media compared to non-fashion media, based on the social comparison theory

Comparison of a web-based 24-h dietary recall tool (Foodbook24) to an interviewer-led 24-h dietary recall

Web-based tools have the potential to reduce the cost of dietary assessment; however, it is necessary to establish their performance compared to traditional dietary assessment methods. This study aims to compare nutrient and food intakes derived from Foodbook24 to those obtained from an interview-led 24-h dietary recall (24HDR). Seventy-nine adult participants completed one self-administered 24HDR using Foodbook24 and one interviewer-led 24HDR on the same day. Following a 10 days wash-out period the same process was completed again in opposite order to the previous study visit. Statistical analysis including Spearman’s rank order correlation, Mann-Whitney U tests, cross-classification analysis, and “Match”, “Omission”, and “Intrusion” rates were used to investigate the relationship between both methods. Strong, positive correlations of nutrient intake estimated using both methods was observed (rs = 0.6–1.0; p < 0.001). The percentage of participants classified into the same tertile of nutrient intake distribution using both methods ranged from 58% (energy) to 82% (vitamin D). The overall match rate for food intake between both methods was 85%, while rates for omissions and intrusions were 11.5% and 3.5%, respectively. These results, alongside the reduced cost and participant burden associated with Foodbook24, highlight the tool’s potential as a viable alternative to the interviewer-led 24HDR

A review of the design and validation of web- and computer-based 24-h dietary recall tools

Technology-based dietary assessment offers solutions to many of the limitations of traditional dietary assessment methodologies including cost, participation rates and the accuracy of data collected. The 24-h dietary recall (24HDR) method is currently the most utilised method for the collection of dietary intake data at a national level. Recently there have been many developments using web-based platforms to collect food intake data using the principles of the 24HDR method. This review identifies web- and computer-based 24HDR tools that have been developed for both children and adult population groups, and examines common design features and the methods used to investigate the performance and validity of these tools. Overall, there is generally good to strong agreement between web-based 24HDR and respective reference measures for intakes of macro- and micronutrients

The development, validation, and user evaluation of foodbook24: A web-based dietary assessment tool developed for the Irish adult population

Background: The application of technology in the area of dietary assessment has resulted in the development of an array of tools, which are often specifically designed for a particular country or region. Objective: The aim of this study was to describe the development, validation, and user evaluation of a Web-based dietary assessment tool “Foodbook24.” Methods: Foodbook24 is a Web-based, dietary assessment tool consisting of a 24-hour dietary recall (24HDR) and food frequency questionnaire (FFQ) alongside supplementary questionnaires. Validity of the 24HDR component was assessed by 40 participants, who completed 3 nonconsecutive, self-administered 24HDR using Foodbook24 and a 4-day semi-weighed food diary at separate time points. Participants also provided fasted blood samples and 24-hour urine collections for the identification of biomarkers of nutrient and food group intake during each recording period. Statistical analyses on the nutrient and food group intake data derived from each method were performed in SPSS version 20.0 (SPSS Inc). Mean nutrient intakes (and standard deviations) recorded using each method of dietary assessment were calculated. Spearman and Pearson correlations, Wilcoxon Signed Rank and Paired t test were used to investigate the agreement and differences between the nutritional output from Foodbook24 (test method) and the 4-day semi-weighed food diary (reference method). Urinary and plasma biomarkers of nutrient intake were used as an objective validation of Foodbook24. To investigate the user acceptability of Foodbook24, participants from different studies involved with Foodbook24 were asked to complete an evaluation questionnaire. Results: For nutrient intake, correlations between the dietary assessment methods were acceptable to very good in strength and statistically significant (range r=.32 to .75). There were some significant differences between reported mean intakes of micronutrients recorded by both methods; however, with the exception of protein (P=.03), there were no significant differences in the reporting of energy or macronutrient intake. Of the 19 food groups investigated in this analysis, there were significant differences between 6 food groups reported by both methods. Spearman correlations for biomarkers of nutrient and food group intake and reported intake were similar for both methods. A total of 118 participants evaluated the acceptability of Foodbook24. The tool was well-received and the majority, 67.8% (80/118), opted for Foodbook24 as the preferred method for future dietary intake assessment when compared against a traditional interviewer led recall and semi-weighed food diary. Conclusions: The results of this study demonstrate the validity and user acceptability of Foodbook24. The results also highlight the potential of Foodbook24, a Web-based dietary assessment method, and present a viable alternative to nutritional surveillance in Ireland

Linguistic Features of Uzbek

This poster provides a preliminary description of the linguistic features of Uzbek, the official language of Uzbekistan. Uzbek is characterized as an Eastern Turkic language within the Altaic language family and, although it is spoken by over 18 million people around the world, it is highly under-documented in linguistic literature. Over the course of a semester, our group met with a native speaker of Uzbek to document the phonological, morphological, and syntactic features of the language. This analysis, along with recordings made by our group, serves the greater linguistic community by providing theoretical linguists with new language data to support their research

DNA from Fingerprints: Attempting Dual Recovery

DNA and Fingerprints are highly prioritised evidence types as they are considered reliable when distinguishing between individuals within a population. Attempts have been documented on recovering both forms of evidence from a single source, but were met with varying success. These studies have however highlighted issues concerning interferences resulting from the methods used to either recover or visualise, with a significant issue lying with contamination or destruction of the DNA by fingerprint enhancement techniques. The aim of the research was to recover DNA prior to enhancement to determine the extent of recovery and damage of both the ridge detail and DNA. Fingerprints were deposited on textured plastic, carrier bags, glass, stainless steel and paper. DNA was recovered by the use of nylon flocked swabs (CopanTM), minitapes (ScenesafeTM) or gelatine lifts (Crime Scene Investigation LimitedTM). Extraction was conducted with QIAmp DNA micro kitTM (QIAGEN®), with Qubit® fluorometry being used for DNA quantification and NGM SelectTM (AmpFISTR®) determining the quality. For fingerprint enhancement; cyanoacrylate, aluminium powder and DFO were used to visualise the prints which were scored using the Centre of Applied Science and Technology (CAST) grading scheme. The gelatine lifts displayed higher detectable levels of DNA along with recovering more donor alleles. The lifts also resulted in the least amount of damage to ridge detail. Minitapes followed in both DNA levels and ridge damage. The nylons swabs displayed a low affinity for collecting DNA while removing all traces of the fingerprints