877 research outputs found

    Proceedings of the 1st Standardized Knowledge Representation and Ontologies for Robotics and Automation Workshop

    Get PDF
    Welcome to IEEE-ORA (Ontologies for Robotics and Automation) IROS workshop. This is the 1st edition of the workshop on! Standardized Knowledge Representation and Ontologies for Robotics and Automation. The IEEE-ORA 2014 workshop was held on the 18th September, 2014 in Chicago, Illinois, USA. In!the IEEE-ORA IROS workshop, 10 contributions were presented from 7 countries in North and South America, Asia and Europe. The presentations took place in the afternoon, from 1:30 PM to 5:00 PM. The first session was dedicated to “Standards for Knowledge Representation in Robotics”, where presentations were made from the IEEE working group standards for robotics and automation, and also from the ISO TC 184/SC2/WH7. The second session was dedicated to “Core and Application Ontologies”, where presentations were made for core robotics ontologies, and also for industrial and robot assisted surgery ontologies. Three posters were presented in emergent applications of ontologies in robotics. We would like to express our thanks to all participants. First of all to the authors, whose quality work is the essence of this workshop. Next, to all the members of the international program committee, who helped us with their expertise and valuable time. We would also like to deeply thank the IEEE-IROS 2014 organizers for hosting this workshop. Our deep gratitude goes to the IEEE Robotics and Automation Society, that sponsors! the IEEE-ORA group activities, and also to the scientific organizations that kindly agreed to sponsor all the workshop authors work

    LIMITS, CHALLENGES, AND OPPORTUNITIES FOR MODERN COUNTERINSURGENCY

    Get PDF
    The overall goal of this thesis is to draw some conclusions about the kinds of strategies and tactics that those engaging in irregular warfare should employ. Given the increasing number of intrastate conflicts and future U.S. involvement in counterinsurgency, it is important for policy makers and strategists to be clear-eyed about viable ways to engage in irregular war. Thus, this paper’s analysis of previous counterinsurgency and stability operations, and estimate of the U.S. military’s institutional capacity to adapt to irregular warfare could serve as a useful guide for future force planning. The first and second chapters of this thesis examine divergent strategies in counterinsurgency and stability operations. Chapter One assesses whether indiscriminate force is strategically effective in national counterinsurgency campaigns. The findings of this chapter indicate that while indiscriminate force may be tactically effective in the near-term, indiscriminate force alone does not produce long-term success. Chapter Two assesses conditions for conflict and stability in Iraq, and why, despite similarly low levels of development and proximity to violence, some areas of Iraq are more stable than others. My research found the examined Shi’a and Kurdish communities in Iraq maintained stability as a result of ethnic homogenization and a capable local security force, rather than COIN and international development efforts. Chapter Three examines U.S. strategic culture and the U.S. military’s ability to adapt to irregular warfare during Operation Iraqi Freedom (OIF). U.S. strategic culture can generally be defined as the historical tendency to focus on high intensity combat operations and conventional capabilities. I analyzed the capacity to adapt on the operational learning level and the institutional level. I concluded that although there is evidence that the U.S. military was adapting to irregular warfare, real institutional adaptation to counterinsurgency was limited by deep-rooted norms characteristic of the American way of war. The purpose of this study is not to argue against the value of conventional military excellence. Tactical successes are important, but many non-lethal efforts and dynamics should be heavily accounted for when engaging in irregular war. The findings of this study offer insights to various limits, challenges, and opportunities for modern counterinsurgency

    EFFECTS OF SHELL DAMAGE ON MORTALITY OF THE EASTERN OYSTER (CRASSOSTREA VIRGINICA) IN NORMOXIC AND ANOXIC CONDITIONS

    Get PDF
    Deoxygenation is increasingly problematic in coastal waters globally, with many costal estuaries subject to zones of hypoxia (< 2 mg/L dissolved oxygen) or anoxia (< 0.5 mg/L dissolved oxygen). The presence of hypoxic and anoxic zones can place a unique physiological burden on marine fauna and flora, potentially leading to mass mortality and resulting in dead zones. Anthropogenic stressors, such as increased nutrient input (primarily Nitrogen and Phosphorus), have led to long-term increases of hypoxia in the Chesapeake Bay over the 20th century. Although environmental management policies for the Bay have mitigated hypoxia trends, hypoxia continues to be prevalent through many parts of the Bay. While motile aquatic organisms can change locations to avoid seasonal or long-term bouts of deoxygenation, organisms with sessile adult life stages cannot move to avoid this ecological stressor. The Eastern Oyster (Crassostrea virginica) is a foundational species in the Chesapeake Bay’s ecosystem, performing many ecosystem services such as water filtration, nutrient cycling, and fostering benthic-pelagic connectivity while also serving as an economic resource for commercial fishing. However, long-term trends in hypoxia and anoxia, combined with other anthropogenic stressors, have contributed to a decline in Eastern Oyster in the Bay, leaving populations at a fraction of historical levels, fostering a need for research to better understand the physiological and biomechanical responses of C. virginica to depletion of dissolved oxygen. While the Eastern Oyster has been termed a champion of hypoxic tolerance, and studies have been published exploring the impacts of low DO on oyster mortality and sublethal responses, research is still in search of answers to whether the response of the oyster comes from shell-based behavioral resilience to isolate the animal from environmental conditions, or physiological adaptions from the tissue of the oyster. By drilling holes of three different sizes into one valve of the oyster and exposing it to anoxic external conditions, this study aims to bridge the gap in knowledge of whether anoxic tolerance is a behavioral or physiological response. Oysters with a hole drilled in the shell of any size experienced much faster mortality in anoxic environments than oysters with no hole in the shell (χ2= 8, p = 0.005), while the size of the hole drilled did not impact time to death. These results shed new light on the behavioral response of the Eastern Oyster to depleted dissolved oxygen and the importance of clamping to ostracize internal tissue from environmental deviations

    Effects of the Human Presence among Robots in the ARIAC 2023 Industrial Automation Competition

    Get PDF
    Acknowledgements The authors thank all NIST employees and interns involved in running ARIAC 2023 and, most importantly, to the teams that took part in the competition.Peer reviewe

    Compact Saloplastic Poly(Acrylic Acid)/Poly(Allylamine) Complexes: Kinetic Control Over Composition, Microstructure, and Mechanical Properties

    Get PDF
    Durable compact polyelectrolyte complexes (CoPECs) with controlled porosity and mechanical properties are prepared by ultracentrifugation. Because thestarting materials, poly(allylamine hydrochloride) (PAH) and poly(acrylic acidsodium salt) (PAA), are weak acids/bases, both composition and morphology are controlled by solution pH. In addition, the nonequilibrium nature of polyelectrolyte complexation can be exploited to provide a range of compositions and porosities under the infl uence of polyelectrolyte addition order and speed, and concentration. Confocal microscopy shows these “saloplastic” materials to be highly porous, where pore formation is attributed to a combination of deswelling of the polyelectrolyte matrix and expansion of small inhomogenities by osmotic pressure. The porosity (15–70%) and the pore size ( &lt; 5 ÎŒ m to &gt; 70 ÎŒ m) of these materials can be tuned by adjusting the PAA to PAH ratio, the salt concentration, and the pH. The modulus of these CoPECs depends on the ratio of the two polyelectrolytes, with stoichiometric complexes being the stiffest due to optimized charge pairing, which correlates with maximized crosslinking density. Mechanical properties, pore sizes, and pore density of these materials make them well suited to three dimensional supports for tissue engineering applications

    SWARMs Ontology: A Common Information Model for the Cooperation of Underwater Robots

    Get PDF
    In order to facilitate cooperation between underwater robots, it is a must for robots to exchange information with unambiguous meaning. However, heterogeneity, existing in information pertaining to different robots, is a major obstruction. Therefore, this paper presents a networked ontology, named the Smart and Networking Underwater Robots in Cooperation Meshes (SWARMs) ontology, to address information heterogeneity and enable robots to have the same understanding of exchanged information. The SWARMs ontology uses a core ontology to interrelate a set of domain-specific ontologies, including the mission and planning, the robotic vehicle, the communication and networking, and the environment recognition and sensing ontology. In addition, the SWARMs ontology utilizes ontology constructs defined in the PR-OWL ontology to annotate context uncertainty based on the Multi-Entity Bayesian Network (MEBN) theory. Thus, the SWARMs ontology can provide both a formal specification for information that is necessarily exchanged between robots and a command and control entity, and also support for uncertainty reasoning. A scenario on chemical pollution monitoring is described and used to showcase how the SWARMs ontology can be instantiated, be extended, represent context uncertainty, and support uncertainty reasoning.Eurpean Commission, H2020, 66210

    Irreversible Adsorption from Dilute Polymer Solutions

    Full text link
    We study irreversible polymer adsorption from dilute solutions theoretically. Universal features of the resultant non-equilibrium layers are predicted. Two cases are considered, distinguished by the value of the local monomer-surface sticking rate Q: chemisorption (very small Q) and physisorption (large Q). Early stages of layer formation entail single chain adsorption. While single chain physisorption times tau_ads are typically microsecs, for chemisorbing chains of N units we find experimentally accessible times tau_ads = Q^{-1} N^{3/5}, ranging from secs to hrs. We establish 3 chemisorption universality classes, determined by a critical contact exponent: zipping, accelerated zipping and homogeneous collapse. For dilute solutions, the mechanism is accelerated zipping: zipping propagates outwards from the first attachment, accelerated by occasional formation of large loops which nucleate further zipping. This leads to a transient distribution omega(s) \sim s^{-7/5} of loop lengths s up to a size s_max \approx (Q t)^{5/3} after time t. By tau_ads the entire chain is adsorbed. The outcome of the single chain adsorption episode is a monolayer of fully collapsed chains. Having only a few vacant sites to adsorb onto, late arriving chains form a diffuse outer layer. In a simple picture we find for both chemisorption and physisorption a final loop distribution Omega(s) \sim s^{-11/5} and density profile c(z) \sim z^{-4/3} whose forms are the same as for equilibrium layers. In contrast to equilibrium layers, however, the statistical properties of a given chain depend on its adsorption time; the outer layer contains many classes of chain, each characterized by different fraction of adsorbed monomers f. Consistent with strong physisorption experiments, we find the f values follow a distribution P(f) \sim f^{-4/5}.Comment: 18 pages, submitted to Eur. Phys. J. E, expanded discussion sectio
    • 

    corecore