A Reference GLL Implementation

The Generalised-LL (GLL) context-free parsing algorithmwas introduced at the 2009 LDTA workshop, and since then aseries of variant algorithms and implementations have beendescribed. There is a wide variety of optimisations that maybe applied to GLL, some of which were already present inthe originally published form.This paper presents a reference GLL implementation shornof all optimisations as a common baseline for the real-worldcomparison of performance across GLL variants. This baselineversion has particular value for non-specialists, sinceits simple form may be straightforwardly encoded in theimplementer’s preferred programming language.We also describe our approach to low level memory managementof GLL internal data structures. Our evaluation onlarge inputs shows a factor 3–4 speedup over a naïve implementationusing the standard Java APIs and a factor 4–5reduction in heap requirements. We conclude with noteson some algorithm-level optimisations that may be appliedindependently of the internal data representation

Analysing the SML97 Definition: Lexicalisation

The specification of the syntax and semantics for Standard ML have been designed to support the generation of a compiler front end, but actual implementations have required significant modification to the specification. Since the specification was written there have been major advances in the development of language analysis systems that can handle general syntax specifications. We are revisiting the SML specification to consider to what extent, using modern tooling, it can be implemented exactly as originally written. In this short paper we focus on the lexical specification

Context-Free Path Querying with Structural Representation of Result

Graph data model and graph databases are very popular in various areas such as bioinformatics, semantic web, and social networks. One specific problem in the area is a path querying with constraints formulated in terms of formal grammars. The query in this approach is written as grammar, and paths querying is graph parsing with respect to given grammar. There are several solutions to it, but how to provide structural representation of query result which is practical for answer processing and debugging is still an open problem. In this paper we propose a graph parsing technique which allows one to build such representation with respect to given grammar in polynomial time and space for arbitrary context-free grammar and graph. Proposed algorithm is based on generalized LL parsing algorithm, while previous solutions are based mostly on CYK or Earley algorithms, which reduces time complexity in some cases.Comment: Evaluation extende

Development and implementation of real time image analysis algorithms

This work concerns the development and implementation of real-time image processing algorithms. Such systems may be applied to industrial inspection problems, which typically require basic operations to be performed on 256 x 256 pixel images in 20 to 100ms using systems costing less than about &pound;20000.Building such systems is difficult because conventional processors executing at around 1MIPS with conventional algorithms are some 2 orders of magnitude too slow. A solution to this is to use a closely coupled array processor such as the DAP, or CLIP4 which is designed especially for image processing. However such a space-parallel architecture imposes its own structure on the problem, and this restricts the class of algorithms which may be efficiently executed to those exhibiting similar space parallelism, i.e. so-called 'parallel algorithms'. This thesis examines an alternative approach which uses a mix of conventional processors and high speed hardware processors. A special frame store has been built for the acquisition and display of images stored in memory on a multiprocessor backplane. Also described are an interface to a host mini-computer, a bus interface to the system and its use with some hardwired and microcoded processors. This system is compared to a single computer operating with a frame store optimised for image processing. The basic software and hardware system described in this thesis has been used in a factory environment for foodproduct inspection.<p

Hot Topic workshop report : Reshaping the food environment – Applying interdisciplinary perspectives in appetite research

Acknowledgments Both AJ and AB and contributed equally to the writing of this article and gratefully acknowledge financial support from the UKRI Medical Research Council (Award MC_PC_19018, £9975) for supporting this workshop. Alex Johnstone gratefully acknowledges financial support from the Scottish Government as part of the Strategic Research Programme at The Rowett Institute (April 2016–March 2022). Adrian Brown gratefully acknowledges funding though the University College London and National Institute for Health Research (NIHR) Biomedical Research funding.Peer reviewedPublisher PD

Changing patterns of human resource management in construction

Recent years have seen increased emphasis on the need for construction organizations to be more client and market oriented—a tantalizing vision of a new quality world driven by clients with an emphasis on best value. This is likely to have significant implications for the business model and management in the industry. However, while construction constitutes an important component of global economic activity, and the very nature of the work is labour intensive, there has been a lack of attention given to the study of human resource management issues. Yet it has long been recognized that the way employees are managed can have important implications for organizational performance, and can even be a differentiator between successful and unsuccessful organizations (Marchington and Wilkinson, 2012). Context-specific factors are believed to partly explain typical approaches to managing people in the sector. These include the nature of complex project-based environments, ingrained cultural norms, cyclical demand and structural flexibility. Delivery of construction projects often requires the coordination of a multiplicity of actors, within a largely fragmented, transient and heterogeneous workforce. The construction industry therefore offers a rich and distinctive context for the study of employment issues, and an interesting counterpoint to the employment models traditionally associated with many manufacturing or service contexts. Much of the existing research tends to paint a fairly bleak picture of employment practices and industrial relations in the construction sector, often depicted as an informal, casualized and even cavalier approach to the management of people with long working hours (Lingard et al., 2008; Townsend et al., 2011) and high rates of health and safety incidents (Loudoun, 2010). Though management styles clearly vary between firms and across countries, thus making it difficult to generalize, the construction industry has been beset by a poor image in relation to approaches to human resource management and workforce relations (International Labour Office, 2001). In contrast to the model of HRM developed by Storey (1995) which emphasizes an approach to people management concerned with developing and utilizing employees in pursuit of organizational objectives, people management in construction is often characterized as a ‘black hole’ or ‘hard HRM’. Perhaps it is a by-product of the gendered nature of the construction industry, but Ness and Green (2012) report hostility of project managers towards HRM as a concept, citing evidence from managers who described investment in HR as ‘a luxury’, ‘namby-pamby’ and viewed HR practitioners as ‘pen pushers’. Indeed the British government has published various reports exhorting the need for a review of traditional employment practices, for both economic and social reasons. Encouragingly, there is also some evidence of the existence of more ‘enlightened’ approaches to managing people. This special issue aims to take stock and evaluate such changes

Integrating products and services through life : an aerospace experience

Purpose - The purpose of this paper is to explore the evolution of "product-service" (P-S) strategies in the aerospace sector. Despite the widespread perception that aerospace organisations are advanced in terms of P-S integration, little is known about the realities of P-S provision in the sector. Much of the existing literature is normative and prescriptive, focusing upon what organisations aspire to do, but offers little insights into how attempts to integrate products and services occur or the challenges organisations encounter. Design/methodology/approach - This paper presents an in-depth case study of an international aerospace original equipment manufacturer, referred to as "JetCo". A total of 18 interviews were conducted with key actors involved in the operationalisation of P-S strategy within defence aerospace and civil aerospace divisions. In addition, analysis of internal company documentation was also undertaken. Findings - This paper reveals that current P-S strategy, which builds upon a long history of service offerings, initially evolved separately in each division in response to the particular markets in which they operate. However, there was evidence of a corporate-wide strategy for P-S provision being developed across divisions to improve co-ordination. This was founded on the recognition that P-S delivery requires the development of a stronger customer orientation, better knowledge and information management strategies and the engagement of employees. A key challenge concerned integrating the product and service parts of the business to ensure consistent delivery of a seamless value offering to customers. Originality/value - The paper offers fresh empirical evidence into the development of P-S in an organisation drawn from a sector often flagged as an exemplar of P-S provision, and provides insights into the complex realities of P-S implementation and delivery. Notably, it highlights the challenge of attempting to embed an organisation-wide "service culture" in pursuit of integrated P-S delivery, and questions the nostrums and overly simplistic models which pervade the current solutions discourse. Aerospace industry After sales service Product life cycle Product management