Agent-Based Markov Modeling for Improved COVID-19 Mitigation Policies

The year 2020 saw the covid-19 virus lead to one of the worst global pandemics in history. As a result, governments around the world have been faced with the challenge of protecting public health while keeping the economy running to the greatest extent possible. Epidemiological models provide insight into the spread of these types of diseases and predict the e_ects of possible intervention policies. However, to date, even the most data-driven intervention policies rely on heuristics. In this paper, we study how reinforcement learning (RL) and Bayesian inference can be used to optimize mitigation policies that minimize economic impact without overwhelming hospital capacity. Our main contributions are (1) a novel agent-based pandemic simulator which, unlike traditional models, is able to model _ne-grained interactions among people at speci_c locations in a community; (2) an RL- based methodology for optimizing _ne-grained mitigation policies within this simulator; and (3) a Hidden Markov Model for predicting infected individuals based on partial observations regarding test results, presence of symptoms, and past physical contacts

Some Economics of Market-Based Distributed Scheduling

Market mechanisms solve distributed scheduling problems by allocating the scheduled resources according to market prices. We model distributed scheduling as a discrete resource allocation problem, and demonstrate the applicability of economic analysis to this framework. Drawing on results from the literature, we discuss the existence of equilibrium prices for some general classes of scheduling problems, and the quality of equilibrium solutions. We then present two protocols for implementing market solutions, and analyze their computational and economic properties.http://deepblue.lib.umich.edu/bitstream/2027.42/60422/1/mb-scheduling-extended.pd

Auction Protocols for Decentralized Scheduling

Scheduling is the problem of allocating resources to alternate possible uses over designated periods of time. Several have proposed (and some have tried) market-based approaches to decentralized versions of the problem, where the competing uses are represented by autonomous agents. Market mechanisms use prices derived through distributed bidding protocols to determine an allocation, and thus solve the scheduling problem. To analyze the behavior of market schemes, we formalize decentralized scheduling as a discrete resource allocation problem, and bring to bear some relevant economic concepts. Drawing on results from the literature, we discuss the existence of equilibrium prices for some general classes of scheduling problems, and the quality of equilibrium solutions. To remedy the potential nonexistence of price equilibria due to complementarity in preference, we introduce additional markets in combinations of basic goods. We present some auction mechanisms and bidding protocols corresponding to the two market structures, and analyze their computational and economic properties. Finally, we consider direct revelation mechanisms, and compare to the market-based approach.http://deepblue.lib.umich.edu/bitstream/2027.42/50443/1/gebfinal.pd

The Use of Software Agents for Autonomous Control of a DC Space Power System

In order to enable manned deep-space missions, the spacecraft must be controlled autonomously using on-board algorithms. A control architecture is proposed to enable this autonomous operation for an spacecraft electric power system and then implemented using a highly distributed network of software agents. These agents collaborate and compete with each other in order to implement each of the control functions. A subset of this control architecture is tested against a steadystate power system simulation and found to be able to solve a constrained optimization problem with competing objectives using only local information

Designing a fashion driving forces website as an educational resource

Electronic educational resources support search activities and manipulate information effectively in learning environments, thus enhancing education. This paper discusses the development of an electronic timeline database that classifies design and fashion details; technological developments; socio-economical influences; availability and popularity within fashion trends; marketing and distribution; and influential people including designers, in a manner that facilitates ease of cross referencing events at the same point in time for a rich analysis of fashion. The study focuses on the driving forces of fashion during the 1920s as a starting point for a much larger database. The data is presented in the form of a website allowing students to better understand fashion trends with macro-environmental and marketing strategies. The electronic resource is a useful tool for fashion, textile and marketing students as an educational interface providing design, production and marketing data for fashion-related products particularly useful for the analysis of fashion trends

An even pattern of xylan substitution is critical for interaction with cellulose in plant cell walls

Xylan and cellulose are abundant polysaccharides in vascular plants and essential for secondary cell wall strength. Acetate or glucuronic acid decorations are exclusively found on even-numbered residues in most of the glucuronoxylan polymer. It has been proposed that this even-specific positioning of the decorations might permit docking of xylan onto the hydrophilic face of a cellulose microfibril. Consequently, xylan adopts a flattened ribbon-like twofold helical screw conformation when bound to cellulose in the cell wall. Here we show that ESKIMO1/XOAT1/TBL29, a xylan-specific O-acetyltransferase, is necessary for generation of the even pattern of acetyl esters on xylan in Arabidopsis. The reduced acetylation in the esk1 mutant deregulates the position-specific activity of the xylan glucuronosyltransferase GUX1, and so the even pattern of glucuronic acid on the xylan is lost. Solid-state NMR of intact cell walls shows that, without the even-patterned xylan decorations, xylan does not interact normally with cellulose fibrils. We conclude that the even pattern of xylan substitutions seen across vascular plants therefore enables the interaction of xylan with hydrophilic faces of cellulose fibrils, and is essential for development of normal plant secondary cell walls.This work was part supported by the Leverhulme Trust grant for the Centre for Natural Material Innovation. J.W.-R., J.J.L. and O.M.T. are supported by studentships from Conicyt Chile and the Cambridge Trusts, the BBSRC Doctoral Training Partnership BB/J014540/1, and a BBSRC Novozymes iCASE award (BB/M015432/1) respectively. We thank K. B. Krogh for co-supervision of O.M.T. The UK 850 MHz solid-state NMR Facility used in this research was funded by EPSRC and BBSRC (Contract reference PR140003), as well as the University of Warwick including via part funding through Birmingham Science City Advanced Materials Projects 1 and 2 supported by Advantage West Midlands (AWM) and the European Regional Development Fund (ERDF)