A comparison of dispatching rules and genetic algorithms for job shop schedules of standard hydraulic cylinders

Hydraulic cylinders perform straight-line reciprocating movements, and they have been used widely in various forms in many different industries. In this paper, we select a sample of the various types of standard hydraulic cylinders. Each cylinder’s near-optimal processing time and the processing order of the cylinder’s parts are investigated using two different techniques. First, we study typical procedures, known as ‘Dispatching Rules’, which would be used in a job shop to resolve scheduling problems. Second, we investigate another kind of technique, called ‘Genetic Algorithms’. The goal of this paper, we show that efficient scheduling solutions are calculated by using dispatching rules and genetic algorithms for manufacturing standard hydraulic cylinders, and we propose that a way to use dispatching rules in association with genetic algorithms should be considered for resolving job shop scheduling problems.     

The significant other: the value of jewellery in the conception,design and experience of body focused digital devices

In this paper, we demonstrate how craft practice in contemporary jewellery opens up conceptions of ‘digital jewellery’ to possibilities beyond merely embedding pre-existing behaviours of digital systems in objects, which follow shallow interpretations of jewellery. We argue that a design approach that understands jewellery only in terms of location on the body is likely to lead to a world of ‘gadgets’, rather than anything that deserves the moniker ‘jewellery’. In contrast, by adopting a craft approach, we demonstrate that the space of digital jewellery can include objects where the digital functionality is integrated as one facet of an object that can be personally meaningful for the holder or wearer.     

A ‘smart house’ is not a home: The domestication of ICTs

This paper discusses the domestication of Information and Communication Technologies (ICTs), particularly their use, in UK households reporting on research undertaken between 1998 and 2004. Issues raised are linked to the dominant discourse of the ‘digital divide’, which in the UK means engaging with ICTs in a ‘meaningful’ way to ensure the economic and social well-being of UK plc (public limited company—in the UK this refers to companies whose shares can be sold to the public. The acronym is used here ironically to indicate the motivation of the government to brand and promote the UK as a whole.). Utilising a framework of understanding digital inequality and the ‘deepening divide’, domestication theory is applied to discuss motivational, material and physical, skills and usage access in the gendered household, critically contrasting this approach to ‘smart house’ research. This qualitative enquiry contributes to the neglected area of domestication studies in Information Systems research.     

Wiki-supported collaborative learning in primary education: How a dialogic space is created for thinking together

This paper explores how wikis may be used to support primary education students’ collaborative interaction and how such an interaction process can be characterised. The overall aim of this study is to analyse the collaborative processes of students working together in a wiki environment, in order to see how primary students can actively create a shared context for learning in the wiki. Educational literature has already reported that wikis may support collaborative knowledge-construction processes, but in our study we claim that a dialogic perspective is needed to accomplish this. Students must develop an intersubjective orientation towards each others’ perspectives, to co-construct knowledge about a topic. For this purpose, our project utilised a ‘Thinking Together’ approach to help students develop an intersubjective orientation towards one another and to support the creation of a ‘dialogic space’ to co-construct new understanding in a wiki science project. The students’ asynchronous interaction process in a primary classroom—which led to the creation of a science text in the wiki—was analysed and characterised, using a dialogic approach to the study of CSCL practices. Our results illustrate how the Thinking Together approach became embedded within the wiki environment and in the students’ collaborative processes. We argue that a dialogic approach for examining interaction can be used to help design more effective pedagogic approaches related to the use of wikis in education and to equip learners with the competences they need to participate in the global knowledge-construction era.     

Memory Consolidation and Forgetting During Sleep: A Neural Network Model

Experimental research with humans and animals suggests that sleep — particularly REM sleep — is, in some way, associated with learning. However, the nature of the association and the underlying mechanism remain unclear. A number of theoretical models have drawn inspiration from research into Artificial Neural Networks. Crick and Mitchinson's ‘unlearning’ and Robins and McCallum's ‘pseudo-rehearsal’ models suggest alternative mechanisms through which sleep could contribute to learning. In this paper we present simulations, suggesting a possible synthesis. Our simulations use a modified version of a Hopfield network to model the possible contribution of sleep to memory consolidation. Sleep is simulated by removing all sensory input to the network and by exposing it to a ‘noise’, intended as a highly abstract model of the signals generated by the Ponto-geniculate-occipital system during sleep. The results show that simulated sleep does indeed contribute to learning and that the relationship between the observed effect and the length of simulated sleep can be represented by a U-shaped curve. It is shown that while high-amplitude, low-frequency noise (reminiscent of NREM sleep) leads to a general reinforcement of memory, low-amplitude, high-frequency noise (as observed in REM sleep) leads to ‘forgetting’ of all but the strongest memory traces. This suggests that a combination of the two kinds of sleep might produce a stronger effect than either kind of sleep on its own and that effective consolidation of memory during sleep may depend not just on REM or NREM sleep but on the overall dynamics of the sleep cycle.     

Wearable Visual Robots

Research work reported in the literature in wearable visual computing has used exclusively static (or non-active) cameras, making the imagery and image measurements dependent on the wearer’s posture and motions. It is assumed that the camera is pointing in a good direction to view relevant parts of the scene at best by virtue of being mounted on the wearer’s head, or at worst wholly by chance. Even when pointing in roughly the correct direction, any visual processing relying on feature correspondence from a passive camera is made more difficult by the large, uncontrolled inter-image movements which occur when the wearer moves, or even breathes. This paper presents a wearable active visual sensor which is able to achieve a level of decoupling of camera movement from the wearer’s posture and motions by a combination of inertial and visual sensor feedback and active control. The issues of sensor placement, robot kinematics and their relation to wearability are discussed. The performance of the prototype robot is evaluated for some essential visual tasks. The paper also discusses potential applications for this kind of wearable robot.     

A new problem for rule following

Wittgenstein saw a problem with the idea that ‘rule following’ is a transparent process. Here I present an additional problem, based on recent ideas about non-Turing computing. I show that even the simplest algorithm—Frege’s successor function, i.e. counting—cannot by itself determine the ‘output’. Specification of a computing machine is also required.     

Tangibles for learning: a representational analysis of physical manipulation

Manipulatives—physical learning materials such as cubes or tiles—are prevalent in educational settings across cultures and have generated substantial research into how actions with physical objects may support children’s learning. The ability to integrate digital technology into physical objects—so-called ‘digital manipulatives’—has generated excitement over the potential to create new educational materials. However, without a clear understanding of how actions with physical materials lead to learning, it is difficult to evaluate or inform designs in this area. This paper is intended to contribute to the development of effective tangible technologies for children’s learning by summarising key debates about the representational advantages of manipulatives under two key headings: offloading cognition—where manipulatives may help children by freeing up valuable cognitive resources during problem solving, and conceptual metaphors—where perceptual information or actions with objects have a structural correspondence with more symbolic concepts. The review also indicates possible limitations of physical objects—most importantly that their symbolic significance is only granted by the context in which they are used. These arguments are then discussed in light of tangible designs drawing upon the authors’ current research into tangibles and young children’s understanding of number.     

Sound,paper and memorabilia: resources for a simpler digital photography

In this paper we reflect on a body of work to develop a simpler form of digital photography. We give three examples of ‘Less is More’ thinking in this area which are directed and inspired by naturalistic user behaviours and reactions to design ideas. Each example happens to review the place of an old technology in the new scheme of things, and challenges a technological trend in the industry. Hence, we consider the role of sound in photography to recommend audiophotographs rather than short video clips as a new media form. We look again at the role of paper in photo sharing and recommend its support and augmentation against the trend towards screen-based viewing. Finally, we consider the role of physical souvenirs and memorabilia alongside photographs, to recommend their use as story triggers and containers, in contrast to explicit multimedia presentations. The implications for simple computing are discussed. This paper originated from the International Forum ‘Less is More—Simple computing in an age of complexity’, 27–28 April 2005, Cambridge UK.     

Qualitative effects of knowledge rules and user feedback in probabilistic data integration

In data integration efforts, portal development in particular, much development time is devoted to entity resolution. Often advanced similarity measurement techniques are used to remove semantic duplicates or solve other semantic conflicts. It proves impossible, however, to automatically get rid of all semantic problems. An often-used rule of thumb states that about 90% of the development effort is devoted to semi-automatically resolving the remaining 10% hard cases. In an attempt to significantly decrease human effort at data integration time, we have proposed an approach that strives for a ‘good enough’ initial integration which stores any remaining semantic uncertainty and conflicts in a probabilistic database. The remaining cases are to be resolved with user feedback during query time. The main contribution of this paper is an experimental investigation of the effects and sensitivity of rule definition, threshold tuning, and user feedback on the integration quality. We claim that our approach indeed reduces development effort—and not merely shifts the effort—by showing that setting rough safe thresholds and defining only a few rules suffices to produce a ‘good enough’ initial integration that can be meaningfully used, and that user feedback is effective in gradually improving the integration quality.     

Introducing contextual laddering to evaluate the likeability of games with children

It becomes more and more recognized that children should be involved in a product’s design and evaluation process. Many findings report on the methodology for usability research with children. However, there has been relatively little analysis of likeability research with children. In this paper, we propose the laddering method—traditionally a marketing method among adults—for likeability research in the domain of child–computer interaction. Three exploratory cases will be described. The cases report on the use of the laddering method with children aged between 7 and 16 to evaluate the likeability of two games. The lessons learnt about the use of the laddering method will be discussed in great detail. In order to adapt the laddering method to work with children, we recommend a variation of this method and call it the ‘contextual laddering method’.     

Crafts praxis for critical wearables design

This paper treats contemporary craft as an under-researched resource for wearable computing, and presents some of the alternative values and experiences that contemporary craft may be able to contribute to the design of personal technological products. Through design and implementation of a suite of wirelessly networked ‘Speckled’ jewellery, it considers contemporary craft for its potential as a critical design resource with especial relevance to wearable computing and the broad development of this paradigm into the everyday. ‘Critical design’ is given a working definition for the purposes of the argument, and a friendship group of five women of retirement age introduced as the user group for this research. Current practice in the contemporary craft genre of jewellery is analysed for its potential as a resource for a critical approach to wearable computing, and based on a set of semi-structured interviews with contemporary jewellery practitioners, the paper presents a set of propositions for a critical craft approach to wearables design.     

Building Urban Narratives: Collaborative Site-Seeing and Envisioning in the MR Tent

The focus of this paper is on studying mixed teams of urban planners, citizens and other stakeholders co-constructing their vision for the future of a site. The MR Tent provides a very specific collaborative setting: an assembly of technologies brought outdoors onto the site of an urban project, which offers vistas onto the site as well as a multiplicity of representations of the site to work with, in different media and taken from different perspectives. The prime focus of this paper is on the complex narratives participants co-constructed in three participatory workshops, with the aim to understand how the core aspects of the MR Tent—spatiality, representation and haptic engagement—shape these narratives. Main findings of this research concern: how the design of the multi-layered space of the MR-Tent supports spatial story-telling; how the different representations of the site of an urban project offer the opportunity to choreograph a ‘site-seeing’ that helps participants understand the site and plan interventions; how the ‘tangibles’ in the MR-Tent encourage a different way of contributing to a shared project and ‘building a vision’.     

Emergence and refinement

Emergent behaviour—system behaviour not determined by the behaviours of system components when considered in isolation—is commonplace in multi-agent systems, particularly when agents adapt to environmental change. This article considers the manner in which Formal Methods may be used to authenticate the trustworthiness of such systems. Techniques are considered for capturing emergent behaviour in the system specification and then the incremental refinement method is applied to justify design decisions embodied in an implementation. To demonstrate the approach, one and two-dimensional cellular automata are studied. In particular an incremental refinement of the ‘glider’ in Conway’s Game of Life is given from its specification.     

Analyzing the semantic content and persuasive composition of extremist media: A case study of texts produced during the Gaza conflict

While terrorism informatics research has examined the technical composition of extremist media, there is less work examining the content and intent behind such media. We propose that the arguments and issues presented in extremist media provide insights into authors’ intent, which in turn may provide an evidence-base for detecting and assessing risk. We explore this possibility by applying two quantitative text-analysis methods to 50 online texts that incite violence as a result of the 2008/2009 Israeli military action in Gaza and the West Bank territories. The first method—a content coding system that identifies the occurrence of persuasive devices—revealed a predominance of moral proof arguments within the texts, and evidence for distinguishable ‘profiles’ of persuasion use across different authors and different group affiliations. The second method—a corpus-linguistic technique that identifies the core concepts and narratives that authors use—confirmed the use of moral proof to create an in-group/out-group divide, while also demonstrating a movement from general expressions of discontent to more direct audience-orientated expressions of violence as conflict heightened. We conclude that multi-method analyses are a valuable approach to building both an evidence-based understanding of terrorist media use and a valid set of applications within terrorist informatics.     

Aligning Text and Phonemes for Speech Technology Applications Using an EM-Like Algorithm

A common requirement in speech technology is to align two different symbolic representations of the same linguistic ‘message’. For instance, we often need to align letters of words listed in a dictionary with the corresponding phonemes specifying their pronunciation. As dictionaries become ever bigger, manual alignment becomes less and less tenable yet automatic alignment is a hard problem for a language like English. In this paper, we describe the use of a form of the expectation-maximization (EM) algorithm to learn alignments of English text and phonemes, starting from a variety of initializations. We use the British English Example Pronunciation (BEEP) dictionary of almost 200,000 words in this work. The quality of alignment is difficult to determine quantitatively since no ‘gold standard’ correct alignment exists. We evaluate the success of our algorithm indirectly from the performance of a pronunciation by analogy system using the aligned dictionary data as a knowledge base for inferring pronunciations. We find excellent performance—the best so far reported in the literature. There is very little dependence on the start point for alignment, indicating that the EM search space is strongly convex. Since the aligned BEEP dictionary is a potentially valuable resource, it is made freely available for research use.     

Unconventional complexity measures for unconventional computers

Unconventional computers—which may, for example, exploit chemical/analogue/quantum phenomena in order to compute, rather than electronically implementing discrete logic gates—are widely studied in both theoretical and practical contexts. One particular motivation behind unconventional computation is the desire efficiently to solve classically difficult problems—we recall chemical-computer attempts at solving NP -complete problems such as the Travelling Salesperson Problem—, with computational complexity theory offering the criteria for judging this efficiency. However, care must be taken here; conventional (Turing-machine-style) complexity analysis is not always appropriate for unconventional computers: new, non-standard computational resources, with correspondingly new complexity measures, are often required. Accordingly, we discuss in the present paper various resources beyond merely time and space (and, indeed, discuss various interpretations of the term ‘resource’ itself), advocating such resources’ consideration when analysing the complexity of unconventional computers. We hope that this acts as a useful starting point for practitioners of unconventional computing and computational complexity.     

Watermark location via back-lighting and recto removal

We consider the problem of locating a watermark in pages of archaic documents that have been both scanned and back-lit: the problem is of interest to codicologists in identifying and tracking paper materials. Commonly, documents of interest are worn or damaged, and all information is victim to very unfavourable signal-to-noise ratios—this is especially true of ‘hidden’ data such as watermarks and chain lines. We present an approach to recto removal, followed by highlighting of such ‘hidden’ data. The result is still of very low signal quality, and we also present a statistical approach to locate watermarks from a known lexicon of fragments. Results are presented from a comprehensively scanned nineteenth century copy of the Qur’ān. The approach has lent itself to immediate exploitation in improving known watermarks, and distinguishing between twin copies. Mr Hiary was supported by the University of Jordan in pursuing this work.     

Antisedentary Beigeless Computing

Conclusion Four decades of sporadic invention and experimentation of and with non-traditional human-computer interface schemes have congealed (somewhat abruptly though not without a few clear-sighted antecedents) into a new field of information system design, here calledAntisedentary Beigeless Computing, that consciously rejects the traditional conception of isolated tete-a-tete between the human and the box-CRT-keyboardmouse. ABC systems instead favour the complementary directions away from this notion of an immobile info-shrine: more personal, intimate, and portable information access; and more diffuse, environmentally-integrated information access. Consideration of ABC projects to date seems to suggest that no single instance can alone express the full generality required of a ‘working’ information system, so that (on the one hand) system design must acknowledge that a complex set of trade-offs involving capabilities, universality, specificity, personalization, and generality is inescapable; while (on the other hand) an ideal, eventual ‘information environment’ will inevitably comprise the careful interweaving of some number of individual ABC systems. Taxonomies and classification schema can rarely hope to be found complete or flawless before the collection of items that they purport to describe have themselves reached the evolutionary stasis of ‘adulthood’ — that is, there is typically some threshold of development or growth beyond which few enough surprises lurk that an encompassing taxonomy can be constructed and observed to reliably encompass, in the longer term. The domain of ABC thought is still quite nascent, and so we would be foolish to assume that all its extremities of form and connotation are now visible, but to the extent that we can already see the outlines of a ‘field’ it is reasonable to make a first run at an analytic taxonomy. The ‘independent character axes’ approach presented here seems broad and loose enough to accommodate any number of additions to the basic stable of ABC systems. It is, further, a taxonomy amenable to significant revision as may be found necessary: axes can be added, deleted, reconstrued, etc. as time and consideration clarify our understanding of ABC. However, it should also be anticipated that the field will eventually coalesce around a much smaller number of better-defined ‘axes’ and thus permit taxonomic reversion to the more hierarchical (and finally more satisfying) ‘Linnean’ scheme we'd originally imagined establishing.     

Cloud Resource Usage—Heavy Tailed Distributions Invalidating Traditional Capacity Planning Models

For years Capacity Planning professionals knew or suspected that various characteristics of computer usage have non-normal distribution. At the same time much of the traditional workload modeling and forecasting is based on mathematical techniques assuming some sort of normality of underlying distributions. If the dissonance between the existing and assumed distribution exists, then resulting capacity models are of lower quality, with possibly erroneous forecasts—and confidence intervals much wider than expected. This paper analyzes distribution of daily resource usage on three storage clusters for 478 days. For each day we consider the distribution of resource usage by customer accounts for five different resources: storage used, storage transactions executed, internal network transfer, egress transfer and inter-data-center transfer—7170 sample distributions in total. All distributions were highly imbalanced and most distribution samples have tails heavier than log-normal, exponential, or normal distributions. These findings spell significant problems for most models assuming normality. Mathematically: Central Limit Theorem does not apply to power-law distributions—so the ‘averaging’ effect cannot be counted on to help with modeling using traditional approach. Operationally: very high volatility found means that the ‘capacity buffers’ need to be large, leading to wasted capacity. Other, administrative, means need to be applied to reduce that. Overall the distributions of resource usage in cloud storage are so far from normal, even after usual transformations, that traditional approach to forecasting and capacity planning needs to be reconsidered. The distributions of log-returns of time series describing resource usage are much more heavy-tailed than similar distributions for stock indexes. Since no financial professional would use linear regression for stock market analysis and forecasting—it stands to reason that capacity planning should move toward employing tools accounting for heavy-tailed distributions, too.