Spatio-textual indexing for geographical search on the web

Many web documents refer to specific geographic localities and many people include geographic context in queries to web search engines. Standard web search engines treat the geographical terms in the same way as other terms. This can result in failure to find relevant documents that refer to the place of interest using alternative related names, such as those of included or nearby places. This can be overcome by associating text indexing with spatial indexing methods that exploit geo-tagging procedures to categorise documents with respect to geographic space. We describe three methods for spatio-textual indexing based on multiple spatially indexed text indexes, attaching spatial indexes to the document occurrences of a text index, and merging text index access results with results of access to a spatial index of documents. These schemes are compared experimentally with a conventional text index search engine, using a collection of geo-tagged web documents, and are shown to be able to compete in speed and storage performance with pure text indexing

An Approach to Splitting Atoms Safely Extended Abstract

AbstractThe intention of this paper is to make a contribution to (compositional) development methods for concurrent programs. The topics touched on include interference, atomicity, observability and granularity. The paper sets out some requirements for an approach to developing systems by “splitting atoms safely”

Fixing the Semantics of Some Concurrent Object-Oriented Concepts Extended Abstract

AbstractConcurrent object-oriented languages provide a suitable target for a compositional design process that copes with the interference inherent with concurrency. Fixing the semantics of an object-based design language has been undertaken using structured operational semantics and by a mapping to the pi-calculus. These two approaches are outlined and contrasted. In particular, the difficulties in the two approaches of justifying the proof rules of the proposed design method are explained

Mechanically coupled laminates with balanced plain weave

Definitive listings of laminate stacking sequences are derived for balanced plain weave laminated materials, assuming each layer is composed of the same material with constant thickness throughout and that standard ply angle orientations 0, 90, and ±45° are adopted; consistent with industrial design practice. A single layer of balanced plain weave material is shown to be immune to thermal distortion following a standard high temperature manufacturing process, which implies that all laminates constructed of this material possess what is commonly referred to as the hygro-thermally curvature-stable or warp-free condition, irrespective of the individual ply orientations used or the laminate stacking sequence definition. A single uncoupled parent laminate class is shown to contain sub-groups with extensionally isotropic and fully isotropic properties that are invariant with off-axis orientation of the principal material axes with respect to the system or structural axes. By contrast a single mechanically coupled parent laminate class is shown to give rise to seven unique forms of coupled laminate through judicious off-axis orientation. Invariant off-axis properties are also identified in coupled laminate designs. Finally, example calculations, abridged stacking sequence listings and design data are presented

Single and multigland disease in primary hyperparathyroidism: Clinical follow-up, histopathology, and flow cytometric DNA analysis

Two-hundred seventy-four patients with primary hyperparathyroidism had selective removal of enlarged parathyroid glands. Biopsies were taken from all parathyroid glands. Normal-size glands were not resected irrespective of their histological appearance. After a mean follow-up of 13.5 years the rates of persistent and recurrent hyperparathyroidism were, respectively, 3.6% and 0.7%. Transient and permanent hypoparathyroidism occurred in 24% and 2.5% of the patients. The microscopic appearance of enlarged glands and of biopsies taken from normal-size glands were reviewed by two pathologists. Normal parathyroid glands were distinguished from abnormal glands fairly accurately (sensitivity 93%, specificity 80%). Microscopic classification of abnormal parathyroid glands as adenomas or hyperplastic glands correlated poorly with the gross classification as single or multigland disease. Flow cytometric DNA analysis of paraffin embedded parathyroid tissue showed significant differences for DNA index, % S-phase and % G2M (p<0.001). Differentiating single from multigland disease by means of DNA analysis was not possible. In conclusion, removal of only enlarged parathyroid glands results in acceptable rates of persistent and recurrent hyperparathyroidism. Biopsies should only be taken sparingly to prevent transient and permanent hypoparathyroidism. Microscopic examination and flow cytometric DNA analysis can differentiate normal from abnormal parathyroid glands but are unable to differentiate abnormal glands into single or multigland disease

An event-based conceptual model for context-aware movement analysis

Current tracking technologies enable collection of data, describing movements of various kinds of objects, including people, animals, icebergs, vehicles, containers with goods and so on. Analysis of movement data is now a hot research topic. However, most of the suggested analysis methods deal with movement data alone. Little has been done to support the analysis of movement in its spatio-temporal context, which includes various spatial and temporal objects as well as diverse properties associated with spatial locations and time moments. Comprehensive analysis of movement requires detection and analysis of relations that occur between moving objects and elements of the context in the process of the movement. We suggest a conceptual model in which movement is considered as a combination of spatial events of diverse types and extents in space and time. Spatial and temporal relations occur between movement events and elements of the spatial and temporal contexts. The model gives a ground to a generic approach based on extraction of interesting events from trajectories and treating the events as independent objects. By means of a prototype implementation, we tested the approach on complex real data about movement of wild animals. The testing showed the validity of the approach

The composition of Event-B models

The transition from classical B [2] to the Event-B language and method [3] has seen the removal of some forms of model structuring and composition, with the intention of reinventing them in future. This work contributes to thatreinvention. Inspired by a proposed method for state-based decomposition and refinement [5] of an Event-B model, we propose a familiar parallel event composition (over disjoint state variable lists), and the less familiar event fusion (over intersecting state variable lists). A brief motivation is provided for these and other forms of composition of models, in terms of feature-based modelling. We show that model consistency is preserved under such compositions. More significantly we show that model composition preserves refinement

Patient Safety Culture: The Impact on Workplace Violence and Health Worker Burnout

Background: Patient and health care worker safety is an interconnected phenomenon. To date, few studies have examined the relationship between patient and worker safety, specifically with respect to work safety culture. Therefore, we examined patient safety culture, workplace violence (WPV), and burnout in health care workers to identify whether patient safety culture factors influence worker burnout and WPV. Methods: This cross-sectional study used secondary survey data sent to approximately 7,100 health care workers at a large academic medical center in the United States. Instruments included the Hospital Survey on Patient Safety Culture, a WPV scale measuring physical and verbal violence perpetrated by patients or visitors, and the Emotional Exhaustion scale from the Maslach Burnout Inventory. Findings: These analyses included 3,312 (47%) hospital staff who directly interacted with patients. Over half of nurse (62%), physician (53%), and allied health professional respondents (52%) reported experiencing verbal violence from a patient, and 39% of nurses and 14% of physicians reported experiencing physical violence from a patient. Burnout levels for nurses (2.67 ± 1.02) and physicians (2.65 ± 0.93) were higher than the overall average for all staff (2.61 ± 1.0). Higher levels of worker-reported patient safety culture were associated with lower odds of WPV (0.47) and lower burnout scores among workers (B = 1.02). Teamwork across units, handoffs, and transitions were dimensions of patient safety culture that also influenced WPV and burnout. Conclusions/Application to Practice: Our findings suggest that improvements in hospital strategies aimed at patient safety culture, including team cohesion with handoffs and transitions, could positively influence a reduction in WPV and burnout among health care workers