The Unreasonable Success of Local Search: Geometric Optimization

What is the effectiveness of local search algorithms for geometric problems in the plane? We prove that local search with neighborhoods of magnitude $1/\epsilon^c$ is an approximation scheme for the following problems in the Euclidian plane: TSP with random inputs, Steiner tree with random inputs, facility location (with worst case inputs), and bicriteria $k$-median (also with worst case inputs). The randomness assumption is necessary for TSP

Energy-efficient algorithms for non-preemptive speed-scaling

We improve complexity bounds for energy-efficient speed scheduling problems for both the single processor and multi-processor cases. Energy conservation has become a major concern, so revisiting traditional scheduling problems to take into account the energy consumption has been part of the agenda of the scheduling community for the past few years. We consider the energy minimizing speed scaling problem introduced by Yao et al. where we wish to schedule a set of jobs, each with a release date, deadline and work volume, on a set of identical processors. The processors may change speed as a function of time and the energy they consume is the $\alpha$th power of its speed. The objective is then to find a feasible schedule which minimizes the total energy used. We show that in the setting with an arbitrary number of processors where all work volumes are equal, there is a $2(1+\varepsilon)(5(1+\varepsilon))^{\alpha -1}\tilde{B}_{\alpha}=O_{\alpha}(1)$ approximation algorithm, where $\tilde{B}_{\alpha}$ is the generalized Bell number. This is the first constant factor algorithm for this problem. This algorithm extends to general unequal processor-dependent work volumes, up to losing a factor of $(\frac{(1+r)r}{2})^{\alpha}$ in the approximation, where $r$ is the maximum ratio between two work volumes. We then show this latter problem is APX-hard, even in the special case when all release dates and deadlines are equal and $r$ is 4. In the single processor case, we introduce a new linear programming formulation of speed scaling and prove that its integrality gap is at most $12^{\alpha -1}$. As a corollary, we obtain a $(12(1+\varepsilon))^{\alpha -1}$ approximation algorithm where there is a single processor, improving on the previous best bound of $2^{\alpha-1}(1+\varepsilon)^{\alpha}\tilde{B}_{\alpha}$ when $\alpha \ge 25$

Using Objective Structured Clinical Examinations (OSCEs) in speech and language therapy pre-registration clinical education

Objective Structured Clinical Examinations (OSCEs) are planned and structured assessments of clinical competence and established practice in medicine and nursing (Alinier, 2003). As performance assessments, they focus on what students can do rather than on theoretical knowledge (Harden, 1988). Students are expected to practice relevant clinical skills throughout placement, and are subsequently assessed on these in designated ‘stations’ demonstrating clinical competence in a specified time. This paper describes our approach to OSCEs in the assessment of clinical skills in pre-registration speech and language therapy (SLT) education

Effectiveness of Local Search for Geometric Optimization

What is the effectiveness of local search algorithms for geometric problems in the plane? We prove that local search with neighborhoods of magnitude 1/epsilon^c is an approximation scheme for the following problems in the Euclidean plane: TSP with random inputs, Steiner tree with random inputs, uniform facility location (with worst case inputs), and bicriteria k-median (also with worst case inputs). The randomness assumption is necessary for TSP

Existing in-between two worlds: supporting asylum seeking women living in temporary accommodation through a creative movement and art intervention

In this reflective article we introduce Moving Space, a creative movement and art project supporting female Asylum Seekers as they move through the transient space of temporary accommodation. We explore how this cross-modal approach supports women to anchor experiences of displacement, loss and trauma through the use of embodied and visual creative process. Moreover, we argue that the transient nature of the therapeutic space brings into focus women’s resourcefulness and resilience despite the adversity and uncertainty they are experiencing

Twilight of the Anthropocene idols

Following on from Theory and the Disappearing Future, Cohen, Colebrook and Miller turn their attention to the eco-critical and environmental humanities’ newest and most fashionable of concepts, the Anthropocene. The question that has escaped focus, as “tipping points” are acknowledged as passed, is how language, mnemo-technologies, and the epistemology of tropes appear to guide the accelerating ecocide, and how that implies a mutation within reading itself—from the era of extinction events.Only in this moment of seeming finality, the authors argue, does there arise an opportunity to be done with mourning and begin reading. Drawing freely on Paul de Man’s theory of reading, anthropomorphism and the sublime, Twilight of the Anthropocene Idols argues for a mode of critical activism liberated from all-too-human joys and anxieties regarding the future. It was quite a few decades ago (1983) that Jurgen Habermas declared that ‘master thinkers had fallen on hard times.’ His pronouncement of hard times was premature. For master thinkers it is the best of times. Not only is the world, supposedly, falling into a complete absence of care, thought and frugality, a few hyper-masters have emerged to tell us that these hard times should be the best of times. It is precisely because we face the end that we should embrace our power to geo-engineer, stage the revolution, return to profound thinking, reinvent the subject, and recognize ourselves fully as one global humanity. Enter anthropos

Split and Rephrase

We propose a new sentence simplification task (Split-and-Rephrase) where the aim is to split a complex sentence into a meaning preserving sequence of shorter sentences. Like sentence simplification, splitting-and-rephrasing has the potential of benefiting both natural language processing and societal applications. Because shorter sentences are generally better processed by NLP systems, it could be used as a preprocessing step which facilitates and improves the performance of parsers, semantic role labellers and machine translation systems. It should also be of use for people with reading disabilities because it allows the conversion of longer sentences into shorter ones. This paper makes two contributions towards this new task. First, we create and make available a benchmark consisting of 1,066,115 tuples mapping a single complex sentence to a sequence of sentences expressing the same meaning. Second, we propose five models (vanilla sequence-to-sequence to semantically-motivated models) to understand the difficulty of the proposed task.Comment: 11 pages, EMNLP 201