A semantics and implementation of a causal logic programming language

The increasingly widespread availability of multicore and manycore computers demands new programming languages that make parallel programming dramatically easier and less error prone. This paper describes a semantics for a new class of declarative programming languages that support massive amounts of implicit parallelism

Datalog as a parallel general purpose programming language

The increasing available parallelism of computers demands new programming languages that make parallel programming dramatically easier and less error prone. It is proposed that datalog with negation and timestamps is a suitable basis for a general purpose programming language for sequential, parallel and distributed computers. This paper develops a fully incremental bottom-up interpreter for datalog that supports a wide range of execution strategies, with trade-offs affecting efficiency, parallelism and control of resource usage. Examples show how the language can accept real-time external inputs and outputs, and mimic assignment, all without departing from its pure logical semantics

A Parallel semantics for normal logic programs plus time

It is proposed that Normal Logic Programs with an explicit time ordering are a suitable basis for a general purpose parallel programming language. Examples show that such a language can accept real-time external inputs and outputs, and mimic assignment, all without departing from its pure logical semantics. This paper describes a fully incremental bottom-up interpreter that supports a wide range of parallel execution strategies and can extract significant potential parallelism from programs with complex dependencies

Ability of modal analysis to detect osseointegration of implants in transfemoral amputees : a physical model study

Owing to the successful use of non-invasive vibration analysis to monitor the progression of dental implant healing and stabilization, it is now being considered as a method to monitor femoral implants in transfemoral amputees. This study uses composite femur-implant physical models to investigate the ability of modal analysis to detect changes at the interface between the implant and bone simulating those that occur during osseointegration. Using electromagnetic shaker excitation, differences were detected in the resonant frequencies and mode shapes of the model when the implant fit in the bone was altered to simulate the two interface cases considered: firm and loose fixation. The study showed that it is beneficial to examine higher resonant frequencies and their mode shapes (rather than the fundamental frequency only) when assessing fixation. The influence of the model boundary conditions on the modal parameters was also demonstrated. Further work is required to more accurately model the mechanical changes occurring at the bone-implant interface in vivo, as well as further refinement of the model boundary conditions to appropriately represent the in vivo conditions. Nevertheless the ability to detect changes in the model dynamic properties demonstrates the potential of modal analysis in this application and warrants further investigation

MAZI Deliverable Report D2.5: – Design, progress and evaluation of the Deptford CreekNet pilot (version 2)

In this deliverable, the second in a series of three, we report on progress in the Creeknet pilot. We describe progress towards tasks identified in the Description of Work (DoW) for Task 2.2, focusing on activities in Year 2 (2017: months 13-24) and look forward to Year 3. The Creeknet pilot consists of four phases. This year, our focus has been on consolidating initial contacts made in Year 1 (Phase 1), and continuing community engagement activities alongside carrying out an initial deployment of the MAZI toolkit with a number of engaged community groups and individuals (Phase 2). In the second half of the year, as the toolkit was developed and an integrated set of tool established these groups and others were invited to engage in further trials, and feedback was gathered to further inform onward development (Phase 3). We have continued with our efforts to build upon existing relationships in Deptford Creek and further afield to help us explore the different ways in which DIY networking in the broadest sense and the use of the MAZI toolkit in particular might help address local challenges. We have reassessed some of our foci through seeking out new opportunities for engagement and trialling the MAZI toolkit. A major activity was planning and running the two day MAZI London Cross-fertilisation symposium. This created the opportunity for Creeknet participants to share their experiences and engage with the other MAZI pilots, bringing together existing community contacts in Deptford Creek, and MAZI partners, and attracted new contributors. Through our activities, working with the emerging MAZI toolkit that evolved through several iterations during the year, we have better understood local circumstances and the complexity involved in the conceptualisation of ‘DIY networking’ - it cannot be assumed to be a single notion. We have identified that both social and technological concerns can restrict its uptake, and consider routes to overcoming these challenges. We provide analysis of work carried out so far, and look towards the future activities

Was There a Structural Break in Barry Bonds’ Bat?

We utilize time series tests to investigate if Barry Bonds’ batting has a deterministic or stochastic trend and to test if structural breaks occur. Bonds’ monthly on base percentage plus slugging percentage (OPS) is examined from 1986 to 2007. We find that Bonds’ OPS is stationary around two level and trend breaks. We find that Bonds’ OPS initially follows a positive trend to the age of 28.9 (June 1993), which coincides roughly with the expected peak performance age (27.6) for a MLB batter as identified by Fair (2008). Following this break, we find that Bonds’ OPS was on a plateau until a second break in September 2000. At this point, at the age of 36.1, Bonds’ OPS jumps up unexpectedly and declines slowly thereafter until his retirement in September 2007 at age 43. Key Words: age-effects, peak performance, baseball, OPS, structural break

Needed skills versus available skills: an assessment tool is launched

Economic development often founders on a mismatch between available workforce skills and companies’ needs. A tool that analyzes critical sets of labor market data not previously considered in tandem can help local governments improve planning.Labor market ; Labor market - Massachusetts ; Occupational training ; Occupational training - Massachusetts

Development of a biaxial compression device for biological samples: preliminary experimental results for a closed cell foam

Biological tissues are subjected to complex loading states in vivo and in order to define constitutive equations that effectively simulate their mechanical behaviour under these loads, it is necessary to obtain data on the tissue's response to multiaxial loading. Single axis and shear testing of biological tissues is often carried out, but biaxial testing is less common. We sought to design and commission a biaxial compression testing device, capable of obtaining repeatable data for biological samples. The apparatus comprised a sealed stainless steel pressure vessel specifically designed such that a state of hydrostatic compression could be created on the test specimen while simultaneously unloading the sample along one axis with an equilibrating tensile pressure. Thus a state of equibiaxial compression was created perpendicular to the long axis of a rectangular sample. For the purpose of calibration and commissioning of the vessel, rectangular samples of closed cell ethylene vinyl acetate (EVA) foam were tested. Each sample was subjected to repeated loading, and nine separate biaxial experiments were carried out to a maximum pressure of 204 kPa (30 psi), with a relaxation time of two hours between them. Calibration testing demonstrated the force applied to the samples had a maximum error of 0.026 N (0.423% of maximum applied force). Under repeated loading, the foam sample demonstrated lower stiffness during the first load cycle. Following this cycle, an increased stiffness, repeatable response was observed with successive loading. While the experimental protocol was developed for EVA foam, preliminary results on this material suggest that this device may be capable of providing test data for biological tissue samples. The load response of the foam was characteristic of closed cell foams, with consolidation during the early loading cycles, then a repeatable load-displacement response upon repeated loading. The repeatability of the test results demonstrated the ability of the test device to provide reproducible test data and the low experimental error in the force demonstrated the reliability of the test data