A Generalized LMI Formulation for Input-Output Analysis of Linear Systems of ODEs Coupled with PDEs

In this paper, we consider input-output properties of linear systems consisting of PDEs on a finite domain coupled with ODEs through the boundary conditions of the PDE. This framework can be used to represent e.g. a lumped mass fixed to a beam or a system with delay. This work generalizes the sufficiency proof of the KYP Lemma for ODEs to coupled ODE-PDE systems using a recently developed concept of fundamental state and the associated boundary-condition-free representation. The conditions of the generalized KYP are tested using the PQRS positive matrix parameterization of operators resulting in a finite-dimensional LMI, feasibility of which implies prima facie provable passivity or L2-gain of the system. No discretization or approximation is involved at any step and we use numerical examples to demonstrate that the bounds obtained are not conservative in any significant sense and that computational complexity is lower than existing methods involving finite-dimensional projection of PDEs

Short Books: Context and Case

The digital transformation of higher education invites rethinking of all elements of academic work. That now includes the form of the scholarly book, including the appearance of short ones, seen by authors and publishers as opportunities for altering expectations and practices. Writing about short books reveals their intentions and utility. And experience with a new series of short books displays their timeliness, if with problems of professional recognition

Professional Learning and Inbetween Publishing: The Tasks of the Charleston Briefings

Should the book and the journal article remain the primary forms of scholarly production in the digital age? That is a question asked by publishing scholar Kathleen Fitzpatrick. She proposes a role for “inbetween” work. Indeed, there is a history of “grey literature” in many fields and of the short book. And academic publishers are experimenting with the form. In this context, an explanation of the rationale for and origins of the Charleston Briefings illustrates the possibilities for experimenting with inbetween publishing featuring subjects of interest to librarians and professionals in allied fields. There follows an account of the genesis, planning, and composition of a forthcoming Briefing on the scholarly workflow. While the length of the Briefings may appear to be its defining element, how it manages its scholarly and educational tasks is the key to meeting its goals and the needs of readers. In this case “inbetweenness” can be an advantage for representing the subject’s timeliness and utility while managing the rapidly growing literature on its different dimensions, including what the digital evolution of the scholarly workflow means for library services

Extension of the Partial Integral Equation Representation to GPDE Input-Output Systems

Partial Integral Equations (PIEs) are an alternative way to model systems governed by Partial Differential Equations (PDEs). PIEs have certain advantages over PDEs in that they are defined by integral (not differential) operators and do not include boundary conditions or continuity constraints on the solution -- a convenience when computing system properties, designing controllers, or performing simulation. In prior work, PIE representations were proposed for a limited class of $2^{nd}$-order PDEs in a single spatial variable. In this paper, we extend the PIE representation to a more general class of PDE systems including, e.g., higher-order spatial derivatives ($N^{th}$-order), PDEs with inputs and outputs, PDEs coupled with ODEs, PDEs with distributed input and boundary effects, and boundary conditions which combine boundary values with inputs and integrals of the state. These extensions are presented in a unified way by first proposing a unified parameterization of PDE systems, which we refer to as a Generalized PDE (GPDE). Given a PDE system in GPDE form, we next propose formulae that takes the GPDE parameters and constructs the Partial Integral (PI) operators that are used to define a PIE system. This formula includes a unitary (and hence invertible) map that converts solutions of the PIE to solutions of the GPDE. This unitary map is then used to show that the original GPDE and PIE have equivalent system properties, including well-posedness and stability. These representations, conversions, and mappings are illustrated through several diverse examples, including beams, mixing problems, entropy modeling, wave equations, etc. Finally, we illustrate the significance of the PIE representation by solving analysis, simulation, and control problems for several representative PDE systems

Duality and H∞H_{\infty}-Optimal Control Of Coupled ODE-PDE Systems

In this paper, we present a convex formulation of $H_{\infty}$-optimal control problem for coupled linear ODE-PDE systems with one spatial dimension. First, we reformulate the coupled ODE-PDE system as a Partial Integral Equation (PIE) system and show that stability and $H_{\infty}$ performance of the PIE system implies that of the ODE-PDE system. We then construct a dual PIE system and show that asymptotic stability and $H_{\infty}$ performance of the dual system is equivalent to that of the primal PIE system. Next, we pose a convex dual formulation of the stability and $H_{\infty}$-performance problems using the Linear PI Inequality (LPI) framework. LPIs are a generalization of LMIs to Partial Integral (PI) operators and can be solved using PIETOOLS, a MATLAB toolbox. Next, we use our duality results to formulate the stabilization and $H_{\infty}$-optimal state-feedback control problems as LPIs. Finally, we illustrate the accuracy and scalability of the algorithms by constructing controllers for several numerical examples

Recently Arrested Adolescents are at High Risk for Sexually Transmitted Diseases

Adolescent offenders may be at high risk for sexually transmitted diseases (STDs). With previous research and interventions focused on incarcerated adolescents, data are needed on STD prevalence and risk factors among newly arrested youth released to the community, a far larger subgroup.Participants were recruited from all arrested youth processed at the Hillsborough County, Florida Juvenile Assessment Center during the last half of 2006 (506 males, 442 females). Participants voluntarily providing urine samples for drug testing as part of standard protocol were also consented to having their specimens split and tested for chlamydia and gonorrhea, using an FDA-approved nucleic acid amplification test.STD prevalence was similar to those previously reported among incarcerated adolescents: 11.5% tested positive for chlamydia, 4.2% for gonorrhea, and 13.2% for either or both infections. Prevalence was significantly higher among females: 19.2% of females had either or both infections compared with 10.5% of males. Prevalence was higher for 17 to 18 year olds (15.2% of males, 25.5% of females), blacks, detained youths, drug users, and those engaged in sexual risk behaviors. Previous STD testing experience was limited.The study indicated that a voluntary STD screening protocol is feasible for arrested youth entering the juvenile justice system, and these offenders are at high risk for STDs. Because most arrested youths are released back to the community, routine testing and treatment of recently arrested youths, and expanded access to risk reduction and prevention programs, can yield substantial public health benefits

Emerging biomarkers in psoriatic arthritis

Psoriasis is an immuneâ mediated skin disease which affects 2â 4% of the worldwide population. Approximately 20â 30% of patients with psoriasis develop psoriatic arthritis (PsA), a frequently destructive and disabling condition. As skin manifestations precede joint symptoms in nearly all patients with PsA, identification of biomarkers for early prediction of joint damage is an important clinical need. Because not all patients with PsA respond to treatment in the same fashion, identification of biomarkers capable of predicting therapeutic response is also imperative. Here, we review existing literature and discuss current investigations to identify potential biomarkers for PsA disease activity, with particular emphasis on microRNAs as novel markers of interest. Serum (soluble) biomarkers, peripheral osteoclast precursor as cellular biomarkers, and genetic loci associated with skin and joint disease are also reviewed. © 2015 IUBMB Life, 67(12):923â 927, 2015Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/136299/1/iub1453.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/136299/2/iub1453_am.pd

Enriched biodiversity data as a resource and service

Background: Recent years have seen a surge in projects that produce large volumes of structured, machine-readable biodiversity data. To make these data amenable to processing by generic, open source “data enrichment” workflows, they are increasingly being represented in a variety of standards-compliant interchange formats. Here, we report on an initiative in which software developers and taxonomists came together to address the challenges and highlight the opportunities in the enrichment of such biodiversity data by engaging in intensive, collaborative software development: The Biodiversity Data Enrichment Hackathon. Results: The hackathon brought together 37 participants (including developers and taxonomists, i.e. scientific professionals that gather, identify, name and classify species) from 10 countries: Belgium, Bulgaria, Canada, Finland, Germany, Italy, the Netherlands, New Zealand, the UK, and the US. The participants brought expertise in processing structured data, text mining, development of ontologies, digital identification keys, geographic information systems, niche modeling, natural language processing, provenance annotation, semantic integration, taxonomic name resolution, web service interfaces, workflow tools and visualisation. Most use cases and exemplar data were provided by taxonomists. One goal of the meeting was to facilitate re-use and enhancement of biodiversity knowledge by a broad range of stakeholders, such as taxonomists, systematists, ecologists, niche modelers, informaticians and ontologists. The suggested use cases resulted in nine breakout groups addressing three main themes: i) mobilising heritage biodiversity knowledge; ii) formalising and linking concepts; and iii) addressing interoperability between service platforms. Another goal was to further foster a community of experts in biodiversity informatics and to build human links between research projects and institutions, in response to recent calls to further such integration in this research domain. Conclusions: Beyond deriving prototype solutions for each use case, areas of inadequacy were discussed and are being pursued further. It was striking how many possible applications for biodiversity data there were and how quickly solutions could be put together when the normal constraints to collaboration were broken down for a week. Conversely, mobilising biodiversity knowledge from their silos in heritage literature and natural history collections will continue to require formalisation of the concepts (and the links between them) that define the research domain, as well as increased interoperability between the software platforms that operate on these concepts