Abstrucr-This paper proposes a new direct adaptive control algorithm which is robust with respect to additive and multiplicative plant unmodeled dynamics. The algorithm is designed based on the reducedorder plant, which is assumed to be minimum phase and of known order and relative degree, but is analyzed with respect to the overall plant which, due to the unmodeled dynamics, may be nonminimum phase and of unknown order and relative degree. It is shown that if the unmodeled dynamics are sufficiently small in the low-frequency range, then the algorithm guarantees boundedness of all signals in the adaptive loop and "small" residual tracking errors for any bounded initial conditions. In the absence of unmodeled dynamics, the residual tracking error is shown to be zero.

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Dysglycemia, in this survey defined as impaired glucose tolerance (IGT) or type 2 diabetes, is common in patients with coronary artery disease (CAD) and associated with an unfavorable prognosis. This European survey investigated dysglycemia screening and risk factor management of patients with CAD in relation to standards of European guidelines for cardiovascular subjects. RESEARCH DESIGN AND METHODS The European Society of Cardiology's European Observational Research Programme (ESC EORP) European Action on Secondary and Primary Prevention by Intervention to Reduce Events (EUROASPIRE) V (2016-2017) included 8,261 CAD patients, aged 18-80 years, from 27 countries. If the glycemic state was unknown, patients underwent an oral glucose tolerance test (OGTT) and measurement of glycated hemoglobin A 1c. Lifestyle, risk factors, and pharmacological management were investigated. RESULTS A total of 2,452 patients (29.7%) had known diabetes. OGTT was performed in 4,440 patients with unknown glycemic state, of whom 41.1% were dysglycemic. Without the OGTT, 30% of patients with type 2 diabetes and 70% of those with IGT would not have been detected. The presence of dysglycemia almost doubled from that selfreported to the true proportion after screening. Only approximately one-third of all coronary patients had completely normal glucose metabolism. Of patients with known diabetes, 31% had been advised to attend a diabetes clinic, and only 24% attended. Only 58% of dysglycemic patients were prescribed all cardioprotective drugs, and use of sodium-glucose cotransporter 2 inhibitors (3%) or glucagon-like peptide 1 receptor agonists (1%) was small. CONCLUSIONS Urgent action is required for both screening and management of patients with CAD and dysglycemia, in the expectation of a substantial reduction in risk of further cardiovascular events and in complications of diabetes, as well as longer life expectancy.

In an effort to understand basic functional mechanisms that can produce epileptic seizures, some key features are introduced in coupled lumped-parameter neural population models that produce "seizure"-like events and dynamics similar to the ones during the route of the epileptic brain towards seizures. In these models, modified from existing ones in the literature, internal feedback mechanisms are incorporated to maintain the normal low level of synchronous behavior in the presence of coupling variations. While the internal feedback is developed using basic feedback systems principles, it is also functionally equivalent to actual neurophysiological mechanisms such as homeostasis that act to maintain normal activity in neural systems that are subject to extrinsic and intrinsic perturbations. Here it is hypothesized that a plausible cause of seizures is a pathology in the internal feedback action; normal internal feedback quickly regulates an abnormally high coupling between the neural populations, whereas pathological internal feedback can lead to "seizure"-like high amplitude oscillations. Several external seizure-control paradigms, that act to achieve the operational objective of maintaining normal levels of synchronous behavior, are also developed and tested in this paper. In particular, closed-loop "modulating" control with predefined stimuli, and closed-loop feedback decoupling control are considered. Among these, feedback decoupling control is the consistently successful and robust seizure-control strategy. The proposed model and remedies are consistent with a variety of recent observations in the human and animal epileptic brain, and with theories from nonlinear systems, adaptive systems, optimization, and neurophysiology. The results from the analysis of these models have two key implications, namely, developing a basic theory for epilepsy and other brain disorders, and the development of a robust seizure-control device through electrical stimulation and/or drug intervention modalities.

The developed framework is expected to assist with the accurate epileptogenic focus localization, reduce hospital stay and healthcare cost, and provide guidance to treatment of epilepsy via resective surgery or neuromodulation.

UDC 519.6To understand basic functional mechanisms that cause epileptic seizures, the paper discusses some key features of theoretical brain functioning models. The hypothesis is put forward that a plausible reason for seizures is pathological feedback in brain circuitry. The analysis of such circuitry has an interesting physical interpretation and may be used to cure epilepsy.

Recent papers have shown advantages of robust controllers compared to controllers based on classical control theory. Further improvements in performance and stable operating range may be realized through the use of multiple robust controllers, but these are typically complicated to synthesize and implement. The complexity is somewhat relaxed for bumpless-transfer controllers, which have appeared in the literature as an ad-hoc gain-scheduling control scheme. The approach is less conservative, easier to synthesize, and easier to implement than a gain scheduled polytopic controller or other interpolation scheme, and has a larger operating range than a nominal controller. In this paper an inverter connected to a microgrid is modeled as a linear parameter varying (LPV) system and bumpless controllers are scheduled using polytopic coordinates and applied to inverters in a microgrid.