State Estimation, Covariance Estimation, and Economic Optimization of Semi-Batch Bioprocesses

One of the most critical aspects of any chemical process engineer is the ability to gather, analyze, and trust incoming process data as it is often required in control and process monitoring applications. In real processes, online data can be unreliable due to factors such as poor tuning, calibration drift, or mechanical drift. Outside of these sources of noise, it may not be economically viable to directly measure all process states of interest (e.g., component concentrations). While process models can help validate incoming process data, models are often subject to plant-model mismatches, unmodeled disturbances, or lack enough detail to track all process states (e.g., dissolved oxygen in a bioprocess). As a result, directly utilizing the process data or the process model exclusively in these applications is often not possible or simply results in suboptimal performance. To address these challenges and achieve a higher level of confidence in the process states, estimation theory is used to blend online measurements and process models together to derive a series of state estimates. By utilizing both sources, it is possible to filter out the noise and derive a state estimate close to the true process conditions. This work deviates from the traditional state estimation field that mostly addresses continuous processes and examines how techniques such as extended Kalman Filter (EKF) and moving horizon estimation (MHE) can be applied to semi-batch processes. Additionally, this work considers how plant-model mismatches can be overcome through parameter-based estimation algorithms such as Dual EKF and a novel parameter-MHE (P-MHE) algorithm. A galacto-oligosaccharide (GOS) process is selected as the motivating example as some process states are unable to be independently measured online and require state estimation to be implemented. Moreover, this process is representative of the broader bioprocess field as it is subject to high amounts of noise, less rigorous models, and is traditionally operated using batch/semi-batch reactors. In conjunction with employing estimation approaches, this work also explores how to effectively tune these algorithms. The estimation algorithms selected in this work require careful tuning of the model and measurement covariance matrices to balance the uncertainties between the process models and the incoming measurements. Traditionally, this is done via ad-hoc manual tuning from process control engineers. This work modifies and employs techniques such as direct optimization (DO) and autocovariance least-squares (ALS) to accurately estimate the covariance values. Poor approximation of the covariances often results in poor estimation of the states or drives the estimation algorithm to failure. Finally, this work develops a semi-batch specific dynamic real-time optimization (DRTO) algorithm and poses a novel costing methodology for this specific type of problem. As part of this costing methodology, an enzyme specific cost scaling correlation is proposed to provide a realistic approximation of these costs in industrial contexts. This semi-batch DRTO is combined with the GOS process to provide an economic analysis using Kluyveromyces lactis (K. lactis) β-galactosidase enzyme. An extensive literature review is carried out to support the conclusions of the economic analysis and motivate application to other bioprocesses

Psychopathology In Adolescents With A History Of Foster Care

Despite the enormous cost of the foster care system, high rates of psychopathology and homelessness among young-adult foster care alumni provide a stark reminder of the challenges faced by this vulnerable population. This study characterizes the effect of a history of foster care on psychopathology in a group of 39 adolescents that had exited foster care and were reunified with their biological mothers. A history of foster care was defined as out-of-home placement by child welfare for at least one month; median foster stay was 1.5 years and median age at placement was 8.5 years. A control group of 78 adolescents was matched with the foster group using exact and logistic-regression nearest-neighbor methods. Matched variables included well-established, major childhood risk factors for the development of psychopathology: maternal substance abuse, maternal psychopathology, and childhood maltreatment (i.e. physical and sexual abuse, neglect and domestic violence). With the two groups matched in this way, recent research suggests that the two groups had comparable histories of adverse childhood events, and thus the major inter-group difference is a temporary separation from the biological mother, enforced by child welfare services (i.e foster care). Participants, and their mothers as second reporters, completed self-report, parent-report and structured interview assessments, providing data on major psychiatric diagnoses and symptom scales. The prevalence of externalizing diagnoses in the foster group was 41.0% (24.9% - 57.2%) compared with 19.2% (10.3% - 28.2%) in the control group (r = .25). Substance dependence prevalence was 25.6% (11.3% - 40.0%) compared with 5.1% (0.1% - 10.1%) in the control group (r = .30). The foster group also had more depression symptoms as measured by three assessments (p \u3c .05, r = .21 to .25); the foster group also had more overall externalizing symptoms (p = .015, r = .22), including conduct problems (p = .007, r = .25) and hyperactivity (p = .023, r = .21). For every comparison made, the foster group demonstrated more psychopathology than controls. Thus despite the protective goal of foster care, it may have detrimental effects on the child\u27s subsequent development. Further studies with larger sample sizes are needed to confirm these findings that have the potential to substantially alter child welfare policy by reducing the number of foster care placements in favor of other child and family support services

Recent Cases: Constitutional Law — Aliens — Right of Due Process in Exclusion Proceedings

An alien, who had resided in the United States for twenty-five years, had married an American citizen and had purchased a home in the United States, left this country to visit his dying mother in Roumania. Upon his return, he was excluded from the United States by order of the Attorney General for security reasons, without a hearing and without being advised of the reason for his exclusion. After detention on Ellis Island for twenty-five months, while attempts to deport him failed because other countries refused to accept him, he sought release by habeas corpus, alleging unlawful confinement. The District Court and the Court of Appeals sustained the writ. Upon certiorari to the United States Supreme Court, held: reversed, four justices dissenting. The alien\u27s prior residence in the United States was immaterial since his present status was that of an entering alien; so denial of a hearing was not violative of due process

Vannotea: A collaborative video indexing, annotation and discussion system for broadband networks

A number of research groups and software companies have developed digital annotation tools for textual documents, web pages, images, audio and video resources. By annotations we mean subjective comments, notes, explanations or external remarks that can be attached to a document or a selected part of a document without actually modifying the document. When a user retrieves a document, they can also download the annotations attached to it from an annotation server to view their peer’s opinions and perspectives on the particular document or to add, edit or update their own annotations. The ability to do this collaboratively and in real time during group discussions is of great interest to the educational, medical, scientific, cultural, defense and media communities. But it is extremely challenging technically and demands significant bandwidth, particularly for video documents. In this paper we describe a unique prototype application developed over the Australian GrangeNet broadband research network, which combines videoconferencing over access grid nodes with collaborative, real-time sharing of an application which enables the indexing, browsing, annotation and discussion of video content between multiple groups at remote locations

Annotating Relationships between Multiple Mixed-media Digital Objects by Extending Annotea

Annotea provides an annotation protocol to support collaborative Semantic Web-based annotation of digital resources accessible through the Web. It provides a model whereby a user may attach supplementary information to a resource or part of a resource in the form of: either a simple textual comment; a hyperlink to another web page; a local file; or a semantic tag extracted from a formal ontology and controlled vocabulary. Hence, annotations can be used to attach subjective notes, comments, rankings, queries or tags to enable semantic reasoning across web resources. More recently tabbed Browsers and specific annotation tools, allow users to view several resources (e.g., images, video, audio, text, HTML, PDF) simultaneously in order to carry out side-by-side comparisons. In such scenarios, users frequently want to be able to create and annotate a link or relationship between two or more objects or between segments within those objects. For example, a user might want to create a link between a scene in an original film and the corresponding scene in a remake and attach an annotation to that link. Based on past experiences gained from implementing Annotea within different communities in order to enable knowledge capture, this paper describes and compares alternative ways in which the Annotea Schema may be extended for the purpose of annotating links between multiple resources (or segments of resources). It concludes by identifying and recommending an optimum approach which will enhance the power, flexibility and applicability of Annotea in many domains

Using the Semantic Grid to Build Bridges between Museums and Indigenous Communities

In this paper we describe a Semantic Grid application designed to enable museums and indigenous communities in distributed locations, to collaboratively discuss, describe, annotate and define the rights associated with objects in museums that originally belonged to or are of cultural or historical significance to indigenous groups. By extending and refining an existing application, Vannotea, we enable users on access grid nodes to collaboratively attach descriptive, rights and tribal care metadata and annotations to digital images, video or 3D representations. The aim is to deploy the software within museums to enable the traditional owners to describe and contextualize museum content in their own words and from their own perspectives. This sharing and exchange of knowledge will hopefully revitalize cultures eroded through colonization and globalization and repair and strengthen relationships between museums and indigenous communities

A synchronous multimedia annotation system for secure collaboratories

In this paper, we describe the Vannotea system - an application designed to enable collaborating groups to discuss and annotate collections of high quality images, video, audio or 3D objects. The system has been designed specifically to capture and share scholarly discourse and annotations about multimedia research data by teams of trusted colleagues within a research or academic environment. As such, it provides: authenticated access to a web browser search interface for discovering and retrieving media objects; a media replay window that can incorporate a variety of embedded plug-ins to render different scientific media formats; an annotation authoring, editing, searching and browsing tool; and session logging and replay capabilities. Annotations are personal remarks, interpretations, questions or references that can be attached to whole files, segments or regions. Vannotea enables annotations to be attached either synchronously (using jabber message passing and audio/video conferencing) or asynchronously and stand-alone. The annotations are stored on an Annotea server, extended for multimedia content. Their access, retrieval and re-use is controlled via Shibboleth identity management and XACML access policies