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In this paper, $H_\infty $ control problem is investigated by off-policy integral reinforcement learning (IRL) method for the nonlinear systems with completely unknown dynamics, disturbances, and constrained-input. Firstly, according to a model-based policy iteration (PI) algorithm, a model-free algorithm is proposed based on the derived iterative equation, and the equivalence of model-based PI algorithm and model-free algorithm is proven. Then, the model-free algorithm is implemented by off-policy IRL technology to solve the Hamilton-Jacobi-Isaacs (HJI) equation with the collected system data by the least-square approach, where three neural networks (NNs) are constructed to approximate the value function, control and the disturbance. Finally, our proposed methods are applied to stabilize an autonomous third-order Chua’s chaotic circuit system and a non-autonomous second-order memristive chaotic circuit system to illustrate the efficiency of the proposed method. [ABSTRACT FROM AUTHOR]

Anguillicoloides crassus is an invasive nematode parasite of the critically endangered European eel, Anguilla anguilla, and possibly one of the primary drivers of eel population collapse, impacting many features of eel physiology and life history. Early detection of the parasite is vital to limit the spread of A. crassus, to assess its potential impact on spawning biomass. However accurate diagnosis of infection could only be achieved via necropsy. To support eel fisheries management we developed a rapid, non-lethal, minimally invasive and in situ DNA-based method to infer the presence of the parasite in the swim bladder. Screening of 131 wild eels was undertaken between 2017 and 2019 in Ireland and UK to validate the procedure. DNA extractions and PCR were conducted using both a Qiagen Stool kit and in situ using Whatman qualitative filter paper No1 and a miniPCR DNA Discovery-System™. Primers were specifically designed to target the cytochrome oxidase mtDNA gene region and in situ extraction and amplification takes approximately 3 h for up to 16 individuals. Our in-situ diagnostic procedure demonstrated positive predictive values at 96% and negative predictive values at 87% by comparison to necropsy data. Our method could be a valuable tool in the hands of fisheries managers to enable infection control and help protect this iconic but critically endangered species. [ABSTRACT FROM AUTHOR]

• A surrogate model based on IRL is suggested, which applies the max-margin method to approximate the reward function. • Under different dynamic environments, IRL learns the reward function and helps accelerate the convergence of the algorithm. • On the basis of learned reward function, IRL-DMOEA generates promising non-dominated solutions during the evolutionary process. Due to the widespread interest in dynamic multiobjective optimization in real-world applications, more and more approaches exploiting machine learning are deployed to tackle this type of problems. Unfortunately, recent works do not make full use of the data obtained during the optimization process, which could be benefit for model training thereby mining the dynamic characteristics of the underlying problem. To address this issue, this paper proposes a dynamic multiobjective evolutionary algorithm driven by inverse reinforcement learning to solve the dynamic multiobjective optimization problems. IRL is widely used to recover the unknown reward function, making it possible to perform at an expert level. The notable features of the proposed algorithm mainly consist of data-driven evolutionary technique, which uses inverse reinforcement learning as a surrogate-assisted model for model training. This design makes full use of the surrogate management strategy based on inverse reinforcement learning to optimize the reward function within a reinforcement learning framework. At the same time, the algorithm can generate a promising policy based on limited training data during the optimization process to achieve better algorithm evolution and guide the search. The experimental results on the benchmark problems validate that the proposed algorithm is effective in dealing with dynamic multiobjective optimization. [ABSTRACT FROM AUTHOR]

In inverse reinforcement learning (IRL), a reward function is learnt to generalize experts' behavior. This paper proposes a model-free IRL algorithm based on an ensemble method, where the reward function is regarded as a parametric function of expected features. In other words, the parameters are updated based on a weak classification method. The IRL is formulated as a problem of a boosting classifier, akin to the renowned Adaboost algorithm for classification, feature expectations from experts' demonstration, and the trajectory induced by an agent's current policy. The proposed approach takes individual feature expectation as attractor or expeller, depending on the sign of the residuals of the state trajectories between expert's demonstration and the one induced by RL with the currently approximated reward function, so as to tackle its central challenges of accurate inference, generalizability, and correctness of prior knowledge. Then, the proposed method is applied further to approximate an abstract reward function from observations of more complex behavior composed of several basic actions. The results of the simulations in a labyrinth are shown to validate the proposed algorithm. Furthermore, behaviors composed of a set of primitive actions on a soccer robot field are examined for the applicability of the proposed method. [ABSTRACT FROM AUTHOR]

In Ireland, policies destined to create a reconfigured binary higher education system are evolving; in the coming years institutes of technology may be redesignated as "technological universities" following a process of voluntary amalgamations and independent reviews against stringent criteria. This overhaul of the sector would satisfy institutions' ambitions to have their status upgraded, and would underpin national policy to address fragmentation and sustainability issues. Drawing on international literature on mergers in higher education, this paper proposes a distinction between push and pull factors as the drivers for exploration and decision making. These two categories of drivers are reviewed in the context of Irish policy development and are applied to an example of a merger that was effected after the publication of the new National Strategy for Higher Education. [ABSTRACT FROM AUTHOR]

The complex effects of the global financial crisis (GFC) have affected countries differently. The concept of stimulus packages to enable economies to withstand its full effects was widespread, as were decisions by several countries to invest in higher education as a means of stimulating the economy while placing workforce development and research on a firmer footing. While the GFC increased awareness of the need to invest in the knowledge economy, governments adopted approaches reflecting their different fundamental priorities. Arguably Ireland was left with little leeway, whereas Australia's far better economic position might have provided an opportunity to invest in higher education through its stimulus packages. This paper examines the policy choices that Australian and Irish governments made both before, and in response to, the GFC to assess how these decisions have prepared higher education for the future. [ABSTRACT FROM AUTHOR]

The article features Dublin, Ireland-based Ntera Ltd.'s NanoChromics display (NCD), which is touted as a beneficial alternative to liquid crystal displays (LCD). NCD exhibits razor sharpness, with nearly black images on an almost luminous and paper-white background. Text is easy to read in most lighting conditions, with contrast ratio of 6:1, and a brightness of at least four times that of an LCD. In terms of power consumption, NCD are power-frugal due to two factors: elimination of the need for any kind of separate lighting system through the high contrast ratio, and absence of a requirement to constantly refresh NCD.

The article reports on the goal of the New Hanseatic League alliance of Denmark, Estonia, Finland, Ireland, Latvia, Lithuania, the Netherlands and Sweden to create reforms to the European Union (EU). Topics discussed include the impact of Brexit on the alliance, France and Germany's common economic position forming the basis for the package of reforms in the EU and the alliance's recruitment of Slovakia to sign its paper on the sovereign bail-out fund.

Focuses on works included in the exhibition, `The Barry Joule Archive: Works on Paper Attributed to Francis Bacon,' at the Irish Museum of Modern Art in Dublin through August 2000. Joule's relationship to Bacon and acquisition of the previously unseen works; Authenticity; Assessment.

The article looks at a 2012 investigation into British involvement in the 1989 assassination of Catholic solicitor Pat Finucane by the loyalist gang Ulster Defence Association (UDA). Topics include papers that detail how British intelligence officers helped plan and British agents in the UDA helped commit Finucane's assassination, British Prime Minister David Cameron's adroitness in admitting British wrongs against Ireland, and how the situation in Ireland has improved since 1989.

The article discusses the role of Irish politicians such as Gerry Adams, the leader of Sinn Fein, in the peace process in Northern Ireland. Adams is busy writing memoirs: life in the modest streets of Catholic west Belfast, occasionally fictionalized and with some immodest use of recycled speeches. There is no mention of his years at the top of the IRA--an organization that he now hints should be disbanded. His fellow republican Martin McGuinness used to be the IRA's chief of staff. Now he looks forward to the day when it devotes itself solely to tending graves. The best-known republican writer is Danny Morrison. He once urged the rank and file to drive the British out of Ireland with the "Armalite and the ballot-box". Now his weapon is the pen. On the other side of the divide, Ian Paisley, the leader of the hard-line Democratic Unionist Party (DUP), has no discernible leisure interests apart from hell and damnation. His party has gone from fire-breathing outsider to the main representative of the province's Unionist majority. It's exchanging papers with the British government about negotiations next month on restoring devolved government. It is the party's ambitious deputy leader, Peter Robinson, who really wants a deal. That would mean less time to indulge his enthusiasm for 1970s-style clothes, and his passionate interest in breeding Koi carp in heated pools in his garden.

Presents updates on environmentalism as of February 2003. Information on a program for reducing plastic bags in Ireland; Location of the largest rooftop solar-power system in the U.S.; Launch of the Better World Travelers Club.