POMDPs are the models of choice for reinforcement learning (RL) tasks where the environment cannot be observed directly. In many applications we need to learn the POMDP structure and parameters from experience and this is considered to be a difficult problem. In this paper we address this issue by modeling the hidden environment with a novel class of models that are less expressive, but easier ...

This paper reports a detailed examination of three lesions of aseptic necrosis of bone occurring in a man who had worked in compressed air eleven years previously. Although two of the lesions were juxta-articular, in neither had the bone collapsed. Histology of only one similar lesion is reported in the literature (McCallum Ct a!. 1966). Necropsy material is considered, together with radiograph...

We describe the FAUST entry to the BioNLP 2011 shared task on biomolecular event extraction. The FAUST system explores several stacking models for combination using as base models the UMass dual decomposition (Riedel and McCallum, 2011) and Stanford event parsing (McClosky et al., 2011b) approaches. We show that using stacking is a straightforward way to improving performance for event extracti...

State abstraction is a useful tool for agents interacting with complex environments. Good state abstractions are compact, reuseable, and easy to learn from sample data. This paper combines and extends two existing classes of state abstraction methods to achieve these criteria. The first class of methods search for MDP homomorphisms (Ravindran 2004), which produce models of reward and transition...

majority rule has been a fundamental principle of corporate governance in the corporations and corporation laws of most countries including england and iran. according to it, shareholders who hold the majority of the corporate shares will take collective decisions in joint stock companies and once taken such decisions will bind the company and every company member even those who were in the min...

Background: Ankle injuries are one of the most common complaints of patients presenting to emergency departments (ED). The Ottawa ankle rules (OAR) was introduced to help physicians to decide who may require x-ray for blunt injuries. The present study aimed at validating the four steps weight-bearing rule of OAR as a sole criterion.    Methods: This prospective observational study wa...