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The book starts out with a motivating chapter to answer the question: Why is it worthwhile to develop system theory? To do so, we jump fearlessly in the very center of our methods, using a simple and straight example in optimization: optimal tracking. Although optimization is not our leading subject– which is system theory– it provides for one of the main application areas, namely the optimization of the performance of a dynamical system in a time-variant environment (for example, driving a car or sending a rocket to the moon). The chapter presents a recursive matrix algebra approach to the optimization problem, known as dynamic programming. Optimal tracking is based on a powerful principle called “dynamic programming,” which lies at the very basis of what ”dynamical” means.
Carbohydrate intake and key food sources of carbohydrates in early childhood are poorly understood. The present study described total carbohydrate intake and subtypes (i.e. starch, sugar), their primary food sources and their tracking among young Australian children. Data from children at ages 9 months (n 393), 18 months (n 284), 3·5 years (n 244) and 5 years (n 240) from the Melbourne InFANT Program were used. Three 24-hour recalls assessed dietary intakes. The 2007 AUSNUT Food Composition Database was used to calculate carbohydrates intake and food groups. Descriptive statistics summarised total carbohydrate and subtype intake and their main food sources. Tracking was examined using Pearson correlations of residualised scores between time points. Total carbohydrate, starch and sugar intakes (g/d) increased across early childhood. The percentage of energy from total carbohydrates (% E) remained stable overtime (48·4–50·5 %). From ages 9 months to 5 years, the %E from total sugar decreased from 29·4 % to 22·6 %, while the %E from starch increased from 16·7 % to 26·0 %. Sources of total carbohydrate intake changed from infant formula at 9 months to bread/cereals, fruits and milk/milk products at 18 months, 3·5 and 5 years. Across all time points, the primary sources of total sugar intake were fruit, milk/milk products and cakes/cookies, whereas main food groups for starch intake included bread/cereals, cakes/cookies and pasta. Weak to moderate tracking of total carbohydrates, total sugar and starch (g/d) was observed. These findings may have the potential to inform the refinement of carbohydrate intake recommendations and design of interventions to improve children’s carbohydrate intake.
Despite thousands of individuals entering the illegal wildlife trade each year, assessments of pangolin populations are largely non-existent, even in areas with high exploitation and limited personnel and field equipment. Although pangolins have unique keratin-based scales, there is no universal scale-marking method for individuals despite some pangolin conservation programmes utilizing marking for reference and cataloguing. Each programme currently establishes and manages its own system, resulting in inconsistencies and limiting data sharing. To facilitate pangolin monitoring and research, we developed a standardized method for assigning individual identification numbers, which we call the Pangolin Universal Notching System. This system is neither resource nor training intensive, which could facilitate its adoption and implementation globally. Its application could help to address knowledge gaps in pangolin ageing, reproduction, survivorship, migration and local trafficking patterns, and could be used in combination with other tagging techniques for research on pangolin biology.
During their northward migration, Red Knots Calidris canutus rufa stop at the Lagoa do Peixe National Park in the extreme south of Brazil to build up fat reserves for their journey to their Canadian breeding grounds. We tracked five Red Knots with PinPoint Argos-75 GPS transmitters to investigate differences in migration strategies from this stopover. Tracked birds used two different routes: the Central Brazil route and the Brazilian Atlantic Coast route. One bird flew 8,300 km straight from Lagoa do Peixe to the Delaware Bay (USA). Another bird stopped in Maranhão (north-east Brazil) and a third one used a yet unknown environment for the species, the mouth of the Amazon River at Baía Santa Rosa, Brazil. These two birds made short flights, covering stretches of 1,600 km to 3,600 km between stop-overs, where they stayed from 4 to 18 days. Our study highlights the occurrence of intrapopulation variation in migratory strategies and reveals the connectivity of environments that are essential for the viability of rufa Red Knot populations.
HPV is the world’s most common sexually transmitted infection: most of us have already acquired it by the time we become adults. While HPV is also the key source of cancer, in theory, it should pose little threat. Medical science already possesses a superior means of tracking, monitoring, and stopping this virus from becoming cervical cancer, and the body carries a natural ability to clear it. And yet, it’s society’s hang-ups about HPV – the stigma of acquiring it through sexual contact – that often get in the way of rationally addressing cervical cancer through widespread vaccination and screening. To encourage people to embrace these two highly effective means of prevention, we must dispel the mysteries of HPV and embrace its ubiquity. If we want to eliminate a cancer caused by a common viral infection, we need to take a closer look at the misguided notions associated with HPV – fears that only foster its spread – and be prepared to defuse them.
Providing all students with an opportunity to be successful is at the core of education. But is that motto truly carried out in the actions and practices of schools. This case study examines the practice of tracking as it relates to Gifted and Talented programs.
The southern giant petrel (Macronectes giganteus) is a widely distributed top predator of the Southern Ocean. To define the fine-scale foraging areas and habitat use of Antarctic breeding populations, 47 southern giant petrels from Nelson Island were GPS-tracked during the summers of 2019–2020 and 2021–2022. Step-selection analysis was applied to test the effects of environmental variables on habitat selection. Visual overlap with seal haul-out sites and fishing areas was also analysed. Birds primarily used waters to the south of the colony in the Weddell and Bellingshausen seas. Females showed a broader distribution, reaching up to -70°S to the west of Nelson Island, while males were mainly concentrated in waters off the northern Antarctic Peninsula. Habitat selection of both sexes was associated with water depth and proximity to penguin colonies. Both overlapped their foraging areas with fishing sites and females in particular overlapped with toothfish fishery blocks in Antarctica and with fishing areas in the Patagonian Shelf. Due to their habitat associations and overlap with fisheries, when harnessed with tracking devices and animal-borne cameras, giant petrels can act as platforms for monitoring the condition and occurrence of penguin colonies, haul-out sites and unregulated fisheries on various temporal and spatial scales in Antarctica.
In 2015 and 2016 four Lesser White-fronted Geese (Anser erythropus), a globally threatened species, were caught and tagged during spring migration representing nearly 10% of the entire Swedish breeding population at the time. Two of the birds were followed over more than one season. Tracking data revealed an unexpected wide network of migration corridors and staging sites. Autumn and spring migration differed by stepping-stone sites and migration speed. So far unknown key stopover sites were discovered in Denmark, northern Germany, and Sweden. By using dynamic Brownian bridge movement models, the potential areas that Lesser White-fronted Geese used during migration are described and conservation implications spotlighted. This study provides another important piece of the puzzle describing the migration of Lesser White-fronted Geese in Western Europe.
Our minds are severely limited in how much information they can extensively process, in spite of being massively parallel at the visual end. When people attempt to track moving objects, only a limited number can be tracked, which varies with display parameters. Associated experiments indicate that spatial selection and updating has higher capacity than selection and updating of features such as color and shape, and is mediated by processes specific to each cerebral hemisphere, such that each hemifield has its own spatial tracking limit. These spatial selection processes act as a bottleneck that gate subsequent processing. To improve our understanding of this bottleneck, future work should strive to avoid contamination of tracking tasks by high-level cognition. While we are far from fully understanding how attention keeps up with multiple moving objects, what we already know illuminates the architecture of visual processing and offers promising directions for new discoveries.
Equipping birds with tags (defined as any item externally attached to birds, including transmitters, loggers and flipper bands, or implanted devices, such as transponders) gives particular insights into animal biology, although researchers may not give systematic consideration of tag impact. We examined 357 papers published between 1986 and 2009 where tags (excluding rings attached to birds’ legs) were used on seabirds, to examine the extent to which researchers considered deleterious effects. Fifty-one (14.3%) papers considered instrumentation effects in their abstract, 31 (60.8%) of which showed statistically significant effects on seabird biology. Of the total data set, 302 (84.6%) articles were classified as ‘indirect’ (with no stated aim to assess the influence of the equipment used) and although most of these (237; 76.5%) did discuss instrumentation effects, this accounted for less than a mean of 2% of the total length of the text. Despite a clear increase in the number of papers based on tagging technology for seabird study over the previous 24 years, there has been no corresponding increase in documentation of the effects of devices on their bearers. We suggest mechanisms by which this issue might be addressed.
In 2019, a Rodent Eradication Project (REP) was implemented on World Heritage listed Lord Howe Island, Australia. Among the species expected to benefit was a burrow-nesting seabird, the Black-winged Petrel Pterodroma nigripennis. Prior to the REP, we assessed causes of Black-winged Petrel nest failure using surveillance cameras. We also measured breeding success before and after the REP and investigated emerging pressures on breeding success from other native species. In 2017, ship rats Rattus rattus were a major cause of Black-winged Petrel nest failure, and breeding success was as low as 2.5%, compared to 47.5% on rodent-free Phillip Island (Norfolk Island Group). In 2020, in the absence of rodents, breeding success on Lord Howe Island increased dramatically to 67% and remained high (50%) in 2021. This result suggests that reproductive output of small seabirds has been heavily supressed by rodents on Lord Howe Island for decades. A subsequent increase in the population of a predatory endemic rail, the Lord Howe Woodhen Hypotaenida sylvestris, combined with burrow competition from Little Shearwaters Puffinus assimilis, indicated that initial high breeding success may not be sustained. However, the surge in successful breeding of Black-winged Petrels is likely to result in a significant increase in fledgling numbers and the recruitment of hundreds of additional birds each year. Given the important role of petrels in global nutrient cycling, and their positive influence on island biodiversity, their expansion should benefit the ecological restoration of Lord Howe Island.
The principal objective of the paper is to show the importance of the Hamiltonian in control theory. Instead of using the Lagrangian formulation of electromechanical or robotic systems, our work is focused on robot dynamics by its Hamiltonian. Using the iterative Newton–Euler, we generate the local Hamiltonians and the derivative of the moments at each joint of the robot manipulator. Thus, we can apply decentralized controllers at each joint. We compare and discuss the efficiency of the controllers. We show that the performance of the sliding modes controller is more robust than that of the PD or Bang–Bang controllers.
The design of a low-cost, flexible, miniaturized, and a high code density chipless radio-frequency identification (RFID) tag is presented as a solution for tracking the transportation of biomass fuel pellets. The performance of the tag is presented and demonstrates the applicability of the design for different material systems, while maintaining a compact size of 5.06 cm2. The tag consists of nested concentric hexagonal elements and a central spiral resonator suitable for ID encoding. The tag presented demonstrates code density of 3.6-bits/cm2, possesses angular stability up to 60°, and high radar cross section (RCS). The tag performance was also observed for tracking 5 kg of fly-ash biomass. Additionally, as the tag mass mostly consists of FR4, PET, or Taconic TLX-0 with a minute mass of either copper, gold, or silver, the tag can be easily combusted and disposed of during biomass combustion. The novel features of this tag are the combination of hexagonal and spiral shape slots for maximum space utilization thereby achieving high RCS signatures along with high code density. All these properties of the proposed chipless RFID tag provide a pioneering pathway for a real-time biomass tracking application.
To address the shortcomings of existing methods for rotorcraft searching, positioning, tracking and landing on a ship at sea, a dual-channel LIDAR searching, positioning, tracking and landing system (DCLSPTLS) is proposed in this paper, which utilises the multi-pulse laser echoes accumulation method and the physical phenomenon that the laser reflectivity of the ship deck in the near-infrared band is four orders of magnitude higher than that of the sea surface. The DCLSPTLS searching and positioning model, tracking model and landing model are established, respectively. The searching and positioning model can provide estimates of the azimuth angle, the distance of the ship relative to the rotorcraft and the ship's course. With the above parameters as inputs, the total tracking time and the direction of the rotorcraft tracking speed can be obtained by using the tracking model. The landing model can calculate the pitch and the roll angles of the ship's deck relative to the rotorcraft by using the least squares method and the laser irradiation coordinates. The simulation shows that the DCLSPTLS can realise the functions of rotorcraft searching, positioning, tracking and landing by using the above parameters. To verify the effectiveness of the DCLSPTLS, a functional test is performed using a rotorcraft and a model ship on a lake. The test results are consistent with the results of the simulation.
Augmented reality (AR) combines digitally generated 3D content with real-world objects that users are looking at. The “virtual” computer-generated 3D content is overlaid on a view of the real world through a specialized display. All augmented reality technologies involve some form of display technology that combines real and virtual content – including headset devices, camera-enabled smartphones and tablets, computer-based webcams, and projectors displaying interactive images on a physical surface. These technologies support real-time tracking of hands, 3D objects, and bodies as they push on or touch virtual objects. This enables a more-natural interaction between the learner and the virtual content. AR technologies support learning by allowing learners to interact with 3D representations; they enable embedded assessments; they support groups of learners engaging with shared virtual objects; and they tap into a child’s natural inclination to play and experiment by moving around and touching and manipulating objects.
This chapter explains how corporate surveillance works on a technical level: how individual users can be tracked across their use of web and mobile services, for example through stateful tracking with cookies or stateless tracking with fingerprinting; how information collected through tracking is consolidated in comprehensive user profiles; how analytics services contribute to tracking and profiling; and how advertising technology works, including ad targeting and ad sales.
This chapter examines findings from transparency research that shed light on the methods used for corporate surveillance, including tracking, profiling, analytics, and advertising. The chapter focuses on key results obtained for the research questions described in chapter 4 and explains the experimental designs used to achieve them.
A behavioral-based strategy for cooperative hunting using drones is proposed in this paper. In this decentralized scheme, each drone acts as an individual agent computing its guidance strategy toward the target based on the relative position of its neighbors without the use of direct communication. The algorithm is based on the deviated pure pursuit methodology, and the emerged behavior mimics a natural hunting formation. Simulations and real-time experiments with varying conditions were carried out to validate the effectiveness of the proposed hunting scheme. Videos of the system in action can be seen on: https://youtu.be/g2dODbd6ZLA.
Community-engaged research (CEnR) is now an established research approach. The current research seeks to pilot the systematic and automated identification and categorization of CEnR to facilitate longitudinal tracking using administrative data. We inductively analyzed and manually coded a sample of Institutional Review Board (IRB) protocols. Comparing the variety of partnered relationships in practice with established conceptual classification systems, we developed five categories of partnership: Non-CEnR, Instrumental, Academic-led, Cooperative, and Reciprocal. The coded protocols were used to train a deep-learning algorithm using natural language processing to categorize research. We compared the results to data from three questions added to the IRB application to identify whether studies had a community partner and the type of engagement planned. The preliminary results show that the algorithm is potentially more likely to categorize studies as CEnR compared to investigator-recorded data and to categorize studies at a higher level of engagement. With this approach, universities could use administrative data to inform strategic planning, address progress in meeting community needs, and coordinate efforts across programs and departments. As scholars and technical experts improve the algorithm’s accuracy, universities and research institutions could implement standardized reporting features to track broader trends and accomplishments.
Can we trust the judgement of machines that see? Computer vision is being entrusted with ever more critical tasks: from access control by face recognition, to diagnosis of disease from medical scans and hand-eye coordination for surgical and nuclear decommissioning robots, and now to taking control of motor vehicles.