Marginal multi-Bernoulli filters: RFS derivation of MHT, JIPDA and association-based MeMBer

Recent developments in random finite sets (RFSs) have yielded a variety of tracking methods that avoid data association. This paper derives a form of the full Bayes RFS filter and observes that data association is implicitly present, in a data structure similar to MHT. Subsequently, algorithms are obtained by approximating the distribution of associations. Two algorithms result: one nearly identical to JIPDA, and another related to the MeMBer filter. Both improve performance in challenging environments.Comment: Journal version at http://ieeexplore.ieee.org/document/7272821. Matlab code of simple implementation included with ancillary file

Hybrid Poisson and multi-Bernoulli filters

The probability hypothesis density (PHD) and multi-target multi-Bernoulli (MeMBer) filters are two leading algorithms that have emerged from random finite sets (RFS). In this paper we study a method which combines these two approaches. Our work is motivated by a sister paper, which proves that the full Bayes RFS filter naturally incorporates a Poisson component representing targets that have never been detected, and a linear combination of multi-Bernoulli components representing targets under track. Here we demonstrate the benefit (in speed of track initiation) that maintenance of a Poisson component of undetected targets provides. Subsequently, we propose a method of recycling, which projects Bernoulli components with a low probability of existence onto the Poisson component (as opposed to deleting them). We show that this allows us to achieve similar tracking performance using a fraction of the number of Bernoulli components (i.e., tracks).Comment: Submitted to 15th International Conference on Information Fusion (2012

Abstracting Asynchronous Multi-Valued Networks: An Initial Investigation

Multi-valued networks provide a simple yet expressive qualitative state based modelling approach for biological systems. In this paper we develop an abstraction theory for asynchronous multi-valued network models that allows the state space of a model to be reduced while preserving key properties of the model. The abstraction theory therefore provides a mechanism for coping with the state space explosion problem and supports the analysis and comparison of multi-valued networks. We take as our starting point the abstraction theory for synchronous multi-valued networks which is based on the finite set of traces that represent the behaviour of such a model. The problem with extending this approach to the asynchronous case is that we can now have an infinite set of traces associated with a model making a simple trace inclusion test infeasible. To address this we develop a decision procedure for checking asynchronous abstractions based on using the finite state graph of an asynchronous multi-valued network to reason about its trace semantics. We illustrate the abstraction techniques developed by considering a detailed case study based on a multi-valued network model of the regulation of tryptophan biosynthesis in Escherichia coli.Comment: Presented at MeCBIC 201

Comparison of intraoral and extraoral scanners on the accuracy of digital model articulation

Introduction: Orthodontists increasingly rely on digital models in clinical practice. The ability of modern scanners to articulate digital models must be scientifically evaluated. Methods:Twenty five digital articulated models were produced from four digital scanners in five experimental groups. The resulting inter-arch measurements were compared to the gold standard. An acceptable range of 0.5mm more or less than the gold standard was used for evaluation. Results: iTero® and iTero® Element yielded all acceptable inter-arch measurements. The 3M™ True Definition and Ortho Insight 3D® with Regisil® bite registration produced four of six acceptable inter-arch measurements. The Ortho Insight 3D® with Coprwax ™ bite registration yielded three of six acceptable inter-ach measurements. Conclusions: The iTero® and iTero® Element produced the most accurately articulated models. The 3M™ True Definition and Ortho Insight 3D® with Regisil® were the next most accurate. The Ortho Insight 3D® scanner with Coprwax ™ was the least accurate method tested

In situ recovery of secondary metabolites using adsorption resins : a thesis presented in partial fulfilment of the requirements for the degree of Master of Philosophy at Massey University, Palmerston North, New Zealand

Almost without exception a two to three fold increase in microbial secondary metabolite concentration was measured when adsorption resins were added in-situ during a submerged liquid fermentation. Anguidine was produced at a final concentration of 440 mg/L after five days in a shake flask that contained adsorption resin, compared to 300 mg/L without resin. Rapamcyin was produced at a final concentration of 87 mg/L after six days in a shake flask that had resin present, compared to 28 mg/L without resin. Ansamitocin P3 was produced at a final concentration of 24 mg/L after six days in a shake flask with resin, compared to 9.75 mg/L without resin. The increase in secondary metabolite concentration confirmed that the resins used provided a positive influence on secondary metabolite production. Adsorption resins for shake flask studies were selected based on their ability to achieve maximum adsorption of specific secondary metabolites in various fermentation systems. A library of adsorbed concentrations was collected for the three secondary metabolites studied. The lipophilicty of the metabolite, calculated by several software packages, was compared to the polarity of the adsorption resin to generate a relationship. By using the preceding set of data it is possible to select adsorption resins that improved the produced concentrations of the target organic secondary metabolites. The fermentation media compositions tested appeared to have no effect on the final product concentration when adsorption resins were added in situ during the fermentations. Based on the lipohilictiy of the secondary metabolite and the polarity of the resins, it is possible to select a resin that achieves a high adsorption concentration of the target organic secondary metabolite

The effect of welfare reform and technological change on unemployment

Unemployment has fallen to its lowest level in a generation. Some welcome this development because they believe it increases the average person's ability to achieve the American dream. Others view low unemployment as a precursor to dire economic consequences. Jason Saving examines the issue of unemployment and reaches three main conclusions. First, welfare reform can significantly reduce unemployment, and the empirical evidence to date suggests the recent American welfare reform effort has caused hundreds of thousands of Americans to leave the welfare rolls and enter the labor force. Second, welfare reform can increase the official unemployment rate, but it cannot increase the number of people who are out of work. Finally, technological change can help low-skilled or disabled individuals become productive members of the labor force, and there is reason to believe it has done so during the 1990s.

European economic integration: a conflict of visions

European Union