Technology enhanced assessment in complex collaborative settings Abstract Building upon discussions by the Assessment Working Group at EDUsummIT 2013, this article reviews recent developments in technology enabled assessments of collaborative problem solving in order to point out where computerised assessments are particularly useful (and where non-computerised assessments need to be retained or developed) while assuring that the purposes and designs are transparent and empowering for teachers and learners. Technology enabled assessments of higher order critical thinking in a collaborative social context can provide data about the actions, communications and products created by a learner in a designed task space. Principled assessment design is required in order for such a space to provide trustworthy evidence of learning, and the design must incorporate and take account of the engagement of the audiences for the assessment as well as vary with the purposes and contexts of the assessment. Technology enhanced assessment enables in-depth unobtrusive documentation or 'quiet assessment' of the many layers and dynamics of authentic performance and allows greater flexibility and dynamic interactions in and among the design features. Most important for assessment FOR learning, are interactive features that allow the learner to turn up or down the intensity, amount and sharpness of the information needed for self-absorption and adoption of the feedback. Most important in assessment OF learning, are features that compare the learner with external standards of performance. Most important in assessment AS learning, are features that allow multiple performances and a wide array of affordances for authentic action, communication and the production of artefacts. Our previous analysis (Webb et al. 2013 ) following discussions at EDUsummIT 2011, identified student and teacher involvement in assessment including digitally-enhanced assessment as critical for 21st century learning. Digitally-enhanced assessments were defined as those that integrate: 1) an authentic learning experience involving digital media with 2) embedded continuous unobtrusive measures of performance, learning and knowledge, which 3) creates a highly detailed, high resolution data record which can be computationally analyzed and displayed so that 4) learners and teachers can immediately utilize the information to improve learning. This unobtrusive measuring approach is a vision of 'quiet assessment' whose volume can be turned up by learners and teachers whenever they wish, in order to check their progress.. This article, developed following further discussions of the Assessment Working Group at EDUsummIT 2013, aims to build on our previous analysis by reviewing recent developments in technology enabled assessments of collaborative problem solving in order to identify examples, approaches and challenges. Furthermore we will point out where computerised assessments are particularly useful (and where noncomputerised assessments need to be retained or developed) while assuring that the purposes and designs are transparent and empowering for teachers and learners. In this article we have discussed recent developments in the assessment of complex knowledge and understanding through the analysis of the OECD PISA design for the assessment of collaborative problem solving in 2015. Our analysis shows that CPS requires a complex task setting with both higher order thinking and social relationships combining to impact learning. The OECD PISA design is a significant step forward in enabling comparative assessment of CPS skills across countries. As we have discussed, this assessment is achieved by simplifying the complexity of collaborative interaction through the use of simulated behaviour of groups and individuals to enable a controlled assessment of individual's CPS skills. Analysis, using ECD, of the domain, problem space and contexts of the PISA 2015 model together with a discussion of the application of the SAMR model of technology integration to assessment OF, FOR and AS learning in the context of CPS has provided a high level outline of the processes and challenges that would be involved in enabling quiet assessment of CPS in an authentic context. As we have seen, the main benefits of technology enhanced assessments would be achieved at the levels of modification and redefinition of the SAMR model where opportunities for combining assessment AS, FOR and OF learning exist. Technical and analytical challenges at these levels include how to segment time and events into metrics of collaboration, how to deal with causal influences with feedback effects and when to zoom in to high-resolution details in order to identify and characterise significant contributions from group members.. In order to achieve the learning benefits that should accrue from these quiet assessments teachers and students will need to be engaged not only in the production of new tools that visualize the information (e.g., to help shape how the new tools provide the most useful and understandable information), but also in the dynamic creation of meaning from the use of those tools in learning situations (e.g., to create personal insights from the experiences as well as the reflections made possible by the new tools). This implies that teachers will need to develop their assessment literacy but these tools in themselves can and should be designed to support teachers in this development. Furthermore, reconceptualising assessment design as a shared process involving teachers enables a focus on the purposes of assessment, with due consideration of validity, while at the same time considering the optimum ways of combining technology enhanced assessment with other methods in order to achieve those purposes. Thus our vision is for a future in which technology supports teachers and students working together with technologies to understand their learning needs, move their learning forward and develop evidence of their achievements. When the EDUsummIT Assessment Working Group met again in 2013 some of the challenges identified in 2011 remained, including uncertainty as to whether and how the following four perspectives on assessment: feedback information, improvement decisions, degree of engagement and understanding, and value judgments, can co-exist to the benefit of learners (Webb et al. 2013) . These perspectives incorporate a focus both on the process of assessment and on the results, as well as highlighting the different purposes of assessment. Even with the increased possibilities that IT provides we have not yet found a way to say confidently that the multiple purposes for which some assessments have been used (Mansell et al. 2009 ) can or should be supported through the same assessment systems. This is because the impacts of some purposes interact with the validation processes of others (Messick 1994) . Note that validation applies to the assessment-in-use not to a particular assessment task. Therefore in considering assessment design for multiple purposes, users need to examine impact factors carefully in order to minimise negative impacts on learning and learners (Webb et al. 2013) . For example, if students were being assessed through an online game, this may be engaging and motivating. If they were encouraged to try hard in order to demonstrate their skills and achieve a badge or some other reward, this may increase their motivation, thereby improving the validity of the assessment. However, if the school district then decided to use the results to make judgements about the school's performance, the assessment would then become high stakes for the school. Therefore the teacher may put pressure on students, thus increasing anxiety for some students and changing the degree of validity of the assessment.. In this review, we assert that integration can occur to meet the multiple purposes, because the affordances of technology can redefine the nature of an assessment task.. We provide a high level outline of the processes for engaging in those considerations in the design of assessments of collaboration, particularly collaborative problem-solving, as exemplified in the Organisation for Economic Co-operation and Development (OECD) draft for the Programme for International Student Assessment (PISA) assessment of the interaction of these two domains (PISA 2013) .. Discussions at EDUsummIT 2013 led to three main recommendations. First, researchers, policy-makers and practitioners agreed to examine and promote assessment of collaborative learning in problem solving environments as an important and complex problem space both for learning and for assessment. For example, significant challenges remain for developing validation approaches that can take account of the complexity of learning experiences for collaborative group tasks. Second, we saw a need to develop theory for big data in educational research (see the article BBig data in educational assessment^ (Gibson and Webb 2015) also in this journal's special edition). Third, we underscored the primacy of the need to engage teachers in the design of learning analytic tools for instructional practices and in interpreting and using results. Here, we will focus on the first recommendation and elements of the third. Specifically we will consider engaging teachers and students in the technology-enabled assessment of collaborative learning. In the related article, we discuss their engagement with big data.. Our reviews and group discussions of global ICT and assessment since 2009 (Webb et al. 2013 ) have combined research-based findings with classroom observations of assessment practices (Black and Wiliam 1998) and evidence-centered assessment design (ECD) (Mislevy et al. 1999) . We examined the ECD framework because it has become quite widely used among designers of computer-based assessment as it makes explicit the interrelationships and substantive arguments among the main elements of the design and implementation: domain models, validity, assessment designs and operational processes (Mislevy et al. 2003) . The framework has diagnostic capabilities and provides opportunities for stakeholders to view estimated competency levels, examine the evidence on which these judgements were based and to use this information for a variety of processes as appropriate (Shute 2011 P.9) . It is also the primary organizing theoretical framework for the PISA assessment of collaborative problem solving (Chauncey and Azevedo 2010) , which we present as an example of the principles under discussion.. The stages of the evidence-centered design process include:. & Domain analysis and modelling that defines the assessment problem space and shapes its affordances; & Using the conceptual assessment framework to define the assessment task, performance model and evidentiary rules that map from student performance to the domain model; & Developing the delivery and sampling plan that defines the media, range of problem space for tasks, and presentation issues.. We will argue that a technology-enabled collaborative learning environment can be a rich context for assessing higher order skills, as long as the purpose and design of the assessment is clear about its targets and the assessment tasks are constructed to include technology as part of the collaborative problem solving task and the assessment provides timely useful feedback to teachers and students.. In the sections that follow, we first review the issues concerning collaborative learning in problem-solving environments with a specific focus on science learning in compulsory education, where some important developments are taking place. Then we examine the broader contexts of technology-based assessment using, the Substitution Augmentation Modification Redefinition (SAMR) Model, that highlights the transformational nature of technology, with a view to considering the potential of technology-based assessments for assessing higher levels of knowledge and performance. Then we mention briefly the further challenges that will need to be addressed in order to utilise big data to assess such higher levels through quiet assessment. We expand our explanation of the significance of developments in big data research in another paper in this special issue (Gibson and Webb 2015) .

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Minimizing Probing Cost and Achieving Identifiability in Probe-Based Network Link Monitoring Abstract-Continuously monitoring link performance is important to network diagnosis. In this paper, we address the problem of minimizing the probing cost and achieving identifiability in probe-based network link monitoring. Given a set of links to monitor, our objective is to select the minimum number of probing paths that can uniquely determine all identifiable links and cover all unidentifiable links. We propose an algorithm based on a linear system model to find out all irreducible sets of probing paths that can uniquely determine an identifiable link, and we extend the bipartite model to reflect the relationship between a set of probing paths and an identifiable link. Since our optimization problem is NP-hard, we propose a heuristic-based algorithm to greedily select probing paths. Our method eliminates two types of redundant probing paths, i.e., those that can be replaced by others and those without any contribution to achieving identifiability. Simulations based on real network topologies show that our approach can achieve identifiability with very low probing cost. Compared with prior work, our method is more general and has better performance. The basic idea of our algorithm is to determine the contribution of a probing path for achieving our objective, and then choose the most useful probing paths and avoid selecting redundant ones. Probing paths have different contributions to uniquely determine identifiable links and cover unidentifiable links. An identifiable link may have many solutions, and a probing path may be in the solutions to multiple identifiable links. Similarly, an unidentifiable link may be covered by several probing paths, and a probing path can cover multiple links.. The linear system model proposed in Section 2.2 can reflect the contribution of a probing path to covering unidentifiable links. For identifiable links, a natural method is to find out all solutions to each identifiable link, and thus we can know which probing paths are the most useful to achieving identifiability. We propose a method based on matrix decomposition and linear replacement to calculate all solutions to an identifiable link in Sections 3.2 and 3.3. Moreover, we develop an extended bipartite model to reflect the relationship between probing paths and target links in Section 3.4. Through this model, we introduce a heuristic-based algorithm in Section 3.5 which can efficiently select probing paths to achieve our objective. End-to-end probe has received considerable attention in network link monitoring. In this paper, we propose an approach to minimize the probing cost and achieve identifiability. Given a set of target links, the objective is to choose the minimum number of probing paths that can uniquely determine identifiable target links and cover unidentifiable target links. The basic idea is to select probing paths that are the most useful for achieving identifiability and covering unidentifiable target links, and prevent choosing redundant probing paths. Our method eliminates two types of redundant probing paths, i.e., those that can be replaced by others and those without any contribution to achieving identifiability. With our approach, the number of selected probing paths is proved to be bounded. Experiments based on ISP topologies demonstrate that our approach can achieve identifiability with very low probing cost. Compared with prior work, our method is more general and has better performance.. The algorithm proposed for calculating all solutions to an identifiable link may generate a large number of path sets when the network scale is large. It is possible that using only a small portion of these path sets can produce good enough results. As future work, we will investigate possible methods to effectively select the probing path sets that are most useful for reducing the overall probing cost. . For more information on this or any other computing topic, please visit our Digital Library at www.computer.org/publications/dlib. Minimizing the probing cost is usually achieved by carefully selecting probing paths. This problem has been studied without resource limitation [3] , [18] , [20] , and in scenarios with explicit operational requirement [9] and resource constraint [31] . Various kinds of probing costs and monitoring objectives have been studied. However, as pointed out in [8] , many network inference problems are ill-posed, because the number of measurements are not sufficient to uniquely determine the result. Our work jointly addresses the problem of minimizing the probing cost and achieving identifiability. Achieving identifiability in network link monitoring is also considered in [4] , [16] , [17] , [18] . However, our work is quite different from theirs. Zhao et al. [4] proposed a method for determining the shortest sequence of links whose properties can be uniquely identified by end-to-end probes. It is similar to differentiating the identifiable from unidentifiable links in our work. However, their method does not consider how to minimize the probing cost. The failure localization in [16] aims at accurately pinpointing a failed link, which in essence is to achieve identifiability. However, it only focuses on locating a single link. Our method is able to uniquely determine every identifiable link. Both [17] and [18] deal with the problem of selecting a minimum set of probing paths that can uniquely determine all identifiable links in the network. It is only a special case of what our algorithm can address, i.e., when all links are target links. Even for this special case, the performance of our solution is guaranteed to be better than or equal to theirs. Another major difference is the method we adopt. Their methods are based on eliminating replaceable paths; i.e., linearly dependent row vectors in the dependency matrix. We take a different approach, and only select probing paths that are the most useful to our objective. In addition to eliminating replaceable probing paths, we also try to avoid selecting probing paths without any contribution to achieving identifiability.. There are some other approaches to infer the delay and loss rate of network links. Nguyen and Thiran [8] exploited the second-order statistics for estimating the loss rate of links. It first infers the variance of the loss rate of links, and then uniquely determines the loss rate of some links with the highest variance. Based on this method, Ghita et al. [10] designed an algorithm to minimize the estimation error rate by carefully selecting links with the highest variance of loss rate. Both approaches focus on providing an estimation of loss rate for each link. However, they do not deal with minimizing the probing cost. Additionally, they do not differentiate identifiable links from unidentifiable links. As a result, the estimated loss rate of an identifiable link may be inaccurate. Compared with them, our approach can obtain the accurate loss rate of each identifiable link.

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Multilayer Markov Random Field models for change detection in optical remote sensing images In this paper, we give a comparative study on three Multilayer Markov Random Field (MRF) based solutions proposed for change detection in optical remote sensing images, called Multicue MRF, Conditional Mixed Markov model, and Fusion MRF. Our purposes are twofold. On one hand, we highlight the significance of the focused model family and we set them against various state-of-the-art approaches through a thematic analysis and quantitative tests. We discuss the advantages and drawbacks of class comparison vs. direct approaches, usage of training data, various targeted application fields and different ways of ground truth generation, meantime informing the Reader in which roles the Multilayer MRFs can be efficiently applied. On the other hand we also emphasize the differences between the three focused models at various levels, considering the model structures, feature extraction, layer interpretation, change concept definition, parameter tuning and performance. We provide qualitative and quantitative comparison results using principally a publicly available change detection database which contains aerial image pairs and Ground Truth change masks. We conclude that the discussed models are competitive against alternative state-of-the-art solutions, if one uses them as pre-processing filters in multitemporal optical image analysis. In addition, they cover together a large range of applications, considering the different usage options of the three approaches. Automatic evaluation of aerial image repositories is an important field of research, since periodically repeated manual processing is time-consuming and cumbersome in cases of high number of images and dynamically changing content. Change detection is an important part of many remote-sensing applications. Some country areas are scanned frequently (e.g. yearby-year) to spot relevant changes, and several repositories contain multitemporal image samples for the same area. Through the extraction of changes, the regions of interest in the images can be significantly decreased in several cases, helping applications of urban development analysis, disaster protection, agricultural monitoring, detection of illegal garbage heaps or wood cuttings. Beside being used as a general preliminary filter, the obtained change map can also provide useful information about size, shape or quantity of the changed areas, which could be applied directly by higher level event detector and object analyzer modules.. However, the definition of "relevant change" is highly taskspecific, leading to a large number of change detection methods with significantly different goals, assumptions and applied tools. Even for a given specific problem the data comparison may be notably challenging, considering that due to the large time lag between two consecutive image samples, one must expect seasonal changes, differences in the obtained data quality and resolution, 3D geometric distortion effects, various viewpoints, different illumination, or results of irrelevant human intervention (such as crop rotation in the arboreous lands). In this paper we gave a comparative survey on three different multilayer MRF solutions, whose main properties are summarized in Table 1 . We have observed that with appropriate feature selection and parametrization we may obtain quite similarly efficient change masks with all the three models, and the results are also competitive with other MRF solutions proposed earlier in the literature. The differences should be often evaluated based on the exact needs of the focused applications: PCC methods are preferred if the changes can be interpreted at the level of well defined segmentation classes, while direct approaches can be trained simply by a batch of positive and negative change examples. Since multilayer MRFs offer flexible model structures, all the three models can be completed with additional features or accommodated to different types of remote sensing data. The paper has shown that although the definition of image clusters and the focused change prototypes are critical tasks in the detection, the different approaches may lead to different, but effective models with established mathematical background. The change detection algorithms in the literature can be grouped based on various aspects. First, they may follow either the Post-Classification Comparison (PCC) or the direct approach. Second, depending on the availability of training data, they can be supervised or unsupervised. Third, they may realize region based (e.g. detecting new forest regions), or object based (e.g. searching for changed buildings) scene interpretation. Szada data set Tiszadob data set Archieve data set (Wiemker, 1997) 4.51 1.70 6.21 3.26 3.39 6.65 2.30 6.76 9.06 Hopfield 4.32 1.98 6.30 4.17 3.16 7.33 8.26 5.86 14.12 Parzen (Bruzzone and Fernandez-Prieto, 2002)

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High finite-sample efficiency and robustness based on distance-constrained maximum likelihood Good robust estimators can be tuned to combine a high breakdown point and a specified asymptotic efficiency at a central model. This happens in regression with MM-and τ -estimators among others. However, the finite-sample efficiency of these estimators can be much lower than the asymptotic one. To overcome this drawback, an approach is proposed for parametric models, which is based on a distance between parameters. Given a robust estimator, the proposed one is obtained by maximizing the likelihood under the constraint that the distance is less than a given threshold. For the linear model with normal errors and using the MM estimator and the distance induced by the Kullback-Leibler divergence, simulations show that the proposed estimator attains a finite-sample efficiency close to one, while its maximum mean squared error is smaller than that of the MM estimator. The same approach also shows good results in the estimation of multivariate location and scatter. Since the seminal work of Huber (1964) and Hampel (1971) , one of the main concerns of the research in robust statistics has been to derive statistical procedures that are simultaneously highly robust and highly efficient under the assumed model.. The efficiency of an estimator is usually measured by the asymptotic efficiency, that is, by the ratio between the asymptotic variances of the maximum likelihood estimator (henceforth MLE) and of the robust estimator. However if the sample size n is not very large, this asymptotic efficiency may be quite different from the finite sample size one, defined as the ratio between the mean squared errors (MSE) of the MLE and of the robust estimator, for samples of size n. However, it is obvious that for practical purposes only the finite sample size efficiency matters.. Consider for example the case of a linear model with normal errors. In this case the MLE of the regression coefficients is the least squares estimator (LSE). It is well known that this estimator is very sensitive to outliers, and in particular its breakdown point is zero. To overcome this problem, several estimators combining high asymptotic breakdown point and high efficiency have been proposed. Yohai (1987) proposed MM-estimators, which have 50% breakdown point and asymptotic efficiency as close to one as desired. Yohai and Zamar (1988) proposed τ −estimates, which combine the same two properties as MM-estimators. Gervini and Yohai (2002) proposed regression estimators which simultaneously have 50% breakdown point and asymptotic efficiency equal to one.. However, as will be seen in Section 2.1, when n is not very large the finite sample efficiency of these estimators may be much smaller than the asymptotic one. On the other hand, a 50% breakdown point does not guarantee that the estimator is highly robust. In fact, this only guarantees that given ε < 0.5 there exists K(ε) such that if the data are contaminated with a fraction of outliers smaller than ε, the norm of the difference between the estimator and the true value is smaller than K(ε). However K(ε) may be very large, which makes the estimator unstable under outlier contamination of size ε. Bondell and Stefanski (2013) proposed a regression estimator with maximum breakdown point and high finite-sample efficiency. However, as it will be seen in Section 2.1, the price for this efficiency is a serious loss of robustness.. The purpose of this paper is to present estimators which have a high finite sample size efficiency and robustness even for small n. Besides, these estimators are highly robust using a robustness criterion better than the breakdown point, namely, the maximum MSE for a given contamination rate ε.. The procedure to define the proposed estimators is very general and may be applied to any parametric or semiparametric model. However in this paper the details are given only to estimate the regression coefficients in a linear model and the multivariate location and scatter of a random vector.. To define the proposed estimators we need an initial robust estimator, not necessarily with high finite sample efficiency. Then the estimators are defined by maximizing the likelihood function subject to the estimate being sufficiently close to the initial one. Doing so we can expect that the resulting estimator will have the maximum possible finite sample efficiency under the assumed model compatible with proximity to the initial robust estimator. This proximity guarantees the robustness of the new estimator.. The formulation of our proposal is as follows. Let D be a distance or discrepancy measure between densities. As a general notation, given a family of distributions with observation vector z, parameter vector θ and density f (z, θ) ,

O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O


Provision of supplementary materials in library and information science scholarly journals Purpose -This study analyses the policies of Library and Information Science (LIS) journals regarding the publication of supplementary materials, the number of journals and articles that include this feature, the kind of supplementary materials published with regard to their function in the article, the formats employed and the access provided to readers.Design/methodology/approach -We analysed the instructions for authors of LIS journals indexed in the ISI Journal Citation Reports, as well as the supplementary materials attached to the articles published in their 2011 online volumes.Findings -Large publishers are more likely to have a policy regarding the publication of supplementary materials, and policies are usually homogeneous across all the journals of a given publisher. Most policies state the acceptance of supplementary materials, and even journals without a policy also publish supplementary materials. The majority of supplementary materials provided in LIS articles are extended methodological explanations and additional results in the form of textual information in PDF or Word files. Some toll-access journals provide open access to any reader to these files.Originality/value -This study provides new insights into the characteristics of supplementary materials in LIS journals. The results may be used by journal publishers to establish a policy on the publication of supplementary materials and, more broadly, to develop data sharing initiatives in academic settings. Primary data are the basis of scientific research. Over the last few years the volume of and speed at which data are obtained and shared have increased enormously due to improved measurement instruments and the use by researchers of the internet for communication. As a result, scholarly communication is going beyond the publication of research reports in the form of journal articles, conference proceedings, monographs, etc. to include the capture, description and reuse of data.. The OECD (2007) defines research data as "factual records (numerical scores, textual records, images and sounds) used as primary sources for scientific research, and that are commonly accepted in the scientific community as necessary to validate research findings". Reflecting the diversity of scientific disciplines, research data can take many forms and may come from many different sources, such as laboratory data, observational data, or public and private records, to name but a few.. In an extensive review of the topic, Borgman (2012) identifies four rationales for sharing research data: 1) to reproduce or verify research (this being the most problematic aim since rarely is enough information provided to reproduce the results, and observations are often associated with specific times and places); 2) to make results of publicly funded research available to the public (which is driving funding agencies to require data release to varying degrees); 3) to enable others to ask new questions in relation to extant data (thereby encouraging meta-analysis, i.e. the combination of data from multiples sources, times and places); and 4) to advance the state of research and innovation (so that researchers can more readily draw upon each other's data). In addition to these rationales, another incentive that could prompt researchers to share their data is a possible increase in the number of citations received (Piwowar, Day & Fridsma, 2007) , an argument that reminds us of the 'citation advantage' commonly attributed to open access articles.. In some sciences, data are managed by disciplinary or national infrastructures that are responsible for collecting, storing, preserving and providing data to researchers. In fields such as astronomy or physics there are standard data practices and sharing research data is unavoidable. However, in 'small science' disciplines, data are collected in order to provide an answer to a specific research question. In these fields, researchers themselves collect the evidence that supports the research process, and the sharing of research data remains a limited activity (Cragin et al., 2010) .. Researchers willing to release their data may choose among three different options: they may deposit data in public repositories, post datasets on public websites, or provide data in journals in the form of supplementary material to articles. The present study focuses on a 'small science' field, namely Library and Information Science (LIS), the aim being to analyse the policies of disciplinary journals regarding the provision of supplementary materials and the characteristics of the materials released.. A growing number of scholarly journals now provide supplementary materials with their articles. According to a survey conducted among publishers (PARSE.Insight, 2009), 71% of large publishers (i.e. those publishing more than 50 journals) and 58% of small publishers (those publishing fewer than 50 journals) allow authors to submit underlying research data with their manuscripts, mainly accepting Office documents, images and plain text. In a note announcing the introduction of a supplementary data feature, the editor of the Journal of Geotechnical and Geoenvironmental Engineering (Stewart, 2010) explained the main rationale for this decision: it would help to address the problem of restrictions in the length of manuscripts and would enable the publication of materials better suited to electronic media than a paper format, such as movies, audios, animations, colour figures, etc. According to this note, these supplementary data would be subject to the same peer review criteria as the manuscript.. The supplementary materials feature seems to be widely employed in scholarly journals. A longitudinal study based on a sample of 28 medical journals (Schriger, 2011) showed that the percentage of journals offering supplementary material in their web version had increased from 32% in 2003 to 64% in 2009, whereas the percentage of articles including this information had increased from 7% to 25%. However, the increase in the amount of supplementary material in journals has not been welcomed by all. Marcus, in an editorial for Cell (2009), enumerated the drawbacks of supplementary materials for authors (who feel impelled to submit increasingly large amounts of supplementary materials), reviewers (who feel responsible for assessing them with the same attention and standards as the main body of the article) and readers (who find it difficult to navigate through large supplements and are unsure about how carefully they have been evaluated). As a result, Cell decided to establish new guidelines in which each item of supplemental data would be specifically associated with This is a postprint (final draft post-refereeing) of an article accepted for publication in Aslib Proceedings 65 (5), 503-514, 2013 a figure or table in the article. In 2010, after seven years of accepting supplementary data, the Journal of Neuroscience decided to stop doing so within journal articles. The reason adduced by the editor (Maunsell, 2010) was, once again, the exponential growth of supplementary materials, which was undermining the peer review process. A year later, it was the turn of the Journal of Experimental Medicine (Borowski, 2011) to announce that, due to the overabundance of supplementary materials, they would limit them "to essential supporting information". Nature Neuroscience has also recently announced changes to its supplementary information guidelines, moderating supplementary materials while expanding the space allowed for methods in the body of the article (Moderating…, 2012).. The changes in the policies of these journals highlight the lack of standards regarding the management of these materials in the publication process: whether they should be edited or reviewed, how to cite them, or how to preserve them (Carpenter, 2010) . As a response to these challenges, the National Information Standards Organization (NISO) and the National Federation of Advanced Information Services (NFAIS) are working to develop recommended practice guidelines for supplemental materials (NISO/NFAIS, 2012).. The value of research data and other supplementary materials varies from discipline to discipline. In fact, it is not clear whether supplementary materials have any use at all, especially in disciplines where data are obtained ad hoc to answer specific research questions and have limited use for other purposes. This variability calls for individual analysis of the characteristics of supplementary material in different fields so as to assess its worth. In this regard, the present article focuses on the analysis of supplementary materials in a set of a 'small science' disciplinary journals. The results will be useful to inform both LIS journal policies regarding the provision of supplemental material and, more broadly, the development of data sharing initiatives, thereby helping to establish standards for the organization and reuse of data. Specifically, the study is underpinned by the following research questions: policy was analysed in order to determine whether or not the journal accepts these materials, and if so, what type of materials does it publish and how are they reviewed.. The next step involved examining the 2011 online volumes of each journal and listing the articles that provided supplementary materials. The characteristics of the supplementary materials were then recorded in terms of their function in the article (additional information on the topic under investigation, methodological details, additional results or additional references), their format (textual, numerical, audio-visual, etc.) , the file formats used, and the availability of the materials to non-subscribers of the journal.. For the purposes of this study, supplementary materials were defined as those considered as such by the journal. In the case of Emerald, six of their journals included 'appendixes' after the references. These appendixes were considered as supplementary materials. Despite the increasing number of journals offering supplementary material features, few of them seem to have considered all the implications. Most policies regarding the publication of these materials are vague and focus mainly on file formats. However, further decisions need to be reached in order to avoid future problems regarding the management and preservation of these data. Indeed, in light of its interest to readers and its future usability by other researchers, journals must establish a policy on whether or not they will publish supplemental material. In establishing such a policy they should consider the typology of materials accepted for publication, the amount of supplementary materials accepted and the review or, at least, the editorial process these materials will be subject to. Journal publishers should also consider whether a link to a public website or, ideally, to a repository providing a stable website would be a better solution.. From the point of view of their utility in LIS, additional methodological explanations seem to be one of the most useful additional resources that can be offered to readers. Methodological details not only increase the credibility of results but also allow other researchers to replicate studies in new contexts.

O O B I O B I I I O B O O O O O O O B I I I O B O O O O B I O O O B O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O B O O O O O O O O O O B I O O B O O O O O B I O O O B I O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O B I O O B O O O O O O O O O O O O O O O O B I O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O B I I I O O O O O O O O O O B O O O O B I O O O O O O O O O O O O B O O B I O O O O O O O O O O O O O O O O O O B O O O B O O O O O O B O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O B O O O O O O O O O O B O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O B O O O O O O O O O O B I O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O


Differential influence of blogs across different stages of decision making: the case of venture capitalists In this work, we followed the sentiment analysis literature, and used supervised learning methods, which take manually classified data (corpus) as input and automatically extract features (combination of words and parts of speech of words) for sentiment analysis (Dave et al. 2003; Ghose and Ipeirotis 2011; Pang et al. 2002; Shanahan et al. 2006) . These supervised methods do not rely on manually or semi-manually constructed discriminant-word lexicons. Prior research has shown that supervised methods perform better than lexicon-based approaches for sentiment analysis (Chaovalit and Zhou 2005; Pang et al. 2002) . We used two dimensions across which we developed in total four classifiers. One dimension used is the venture category provided by VCs, and the two categories provided are software and IT services. The second dimension used is the media type, and the two media types are blog posts and media and press releases. Next, taking an example of classifier for blog posts under venture category software, we provide details about how we constructed a classifier. We randomly picked 600 blog posts for ventures under the category software. Three raters (graduate students) then manually classified posts into one of the following three categories: positive, negative, and neutral. Each post was categorized by two randomly assigned raters out of three raters. In the case of disagreement, the third rater's judgment was considered as final. To check for inter-rater reliability, we calculated Cohen's kappa between each two pairs (Cohen 1960). Cohen's kappa is a statistical measure for examining the reliability of agreement between two raters when categorizing items. Cohen's kappa came out to be 0.807, 0.812, and 0.818, which connotes almost perfect agreement among raters (Landis and Koch 1977). The manually classified corpus was then used to construct a classifier using a language-based model, namely, the dynamic language model (Carpenter 2005), using LingPipe. Typically past studies use n-gram (specifically, n = 8) based character language model with a generalized form of Witten-Bell smoothing to create a classifier from the manually classified corpus (Ghose and Ipeirotis 2011). Using this approach, the accuracy of our classifier was 70.12 percent, which is quite good. However, in this study, we needed to classify posts into three categories, and previous research on sentiment analysis has shown that in such situations, pair-wise coupling with stacking gives better results than a single multivariate classifier (Koppel and Schler 2006) . The basic idea of pair-wise coupling is to convert c-class problem into series of binary classification problems by learning one classifier for each pair. This is accomplished by using training data of the pair alone and ignoring rest of the data. The predictions from these classifiers are then combined via a framework referred to as stacking-mapping of each of 2 c possible outcomes to a particular class c (Wolpert 1992). This approach requires us to built three binary classifiers-positive/negative, negative/neutral,A1

O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O


Design of Competitive Web Services Using QFD for Satisfaction of QoS Requirements It is the key concern for service providers that how a web service stands out among functionally similar services. QoS is a distinct and decisive factor in service selection among functionally similar services. Therefore, how to design services to meet customers' QoS requirements is an urgent problem for service providers. This paper proposes an approach using QFD (Quality Function Deployment) which is a quality methodology to transfer services' QoS requirements into services' design attribute characteristics. Fuzzy set is utilized to deal with subjective and vague assessments such as importance of QoS properties. TCI (Technical Competitive Index) is defined to compare the technical competitive capacity of a web service with those of other functionally similar services in the aspect of QoS. Optimization solutions of target values of service design attributes is determined by GA (Genetic Algorithm) in order to make the technical performance of the improved service higher than those of any other rival service products with the lowest improvement efforts. Finally, we evaluate candidate improvement solutions on cost-effectiveness. As the output of QFD process, the optimization targets and order of priority of service design attributes can be used as an important basis for developing and improving service products. SOC (Service Oriented Computing), as a new computing paradigm, is changing the way of developing the information system. It can loosely couple web services provided by different providers so that enterprises response quickly to changes in business processes. Web services as a basic technology for SOC have become more frequently used.. QoS is an important aspect of web services. It is crucial to the success of a web service, especially in the situation of more than one web services with similar functions on the market. How to design a web service is a challenge for service providers to meet customers' QoS requirements and make the web service more competitive than other services with similar functions in terms of QoS.. QFD (Quality Function Deployment) is one of the major quality methodologies, which transfers customers' requirements into product characteristics during the design process. QFD, proposed in Japan [1] , has now become an important quality design technology worldwide. It is an effective technology to meet customer requirements and win the market competition. So we use QFD to design web services and trace customers' QoS requirements into design attributes of web services. It can make the designed web services reflect QoS requirements by using QFD. The targets and order of priority of design attributes of web services are the output of QFD. Because the QFD process involves subjective and vague assessment, caused by the cognitive limit, fuzzy logic has been used for expressing degrees in linguistic terms. Fuzzy assessment with these terms is frequently intuitive and effective for decision-makers. During the process of determining the targets of design attributes of web services, we use GA (Genetic Algorithm), which can solve global optimization problems rapidly, to find the optimization target solutions. The solutions can make the designed web services more competitive than other services with similar functions in terms of QoS within the lowest efforts for the web service providers, such as on development cost.. The remainder of this paper is organized as follows. Section 2 discusses some related works about QoS of web services and QFD. Section 3 describes our approach to design web services using Fuzzy QFD to meet QoS requirements, including the determination of importance and technical targets of web service design attributes. Section 4 presents a web service system example to illustrate our approach and proposes a ROI decision analysis diagram to analyze the output solutions on cost-effectiveness. Finally, Sect. 5 concludes the paper. This paper applies QFD to web service design, which traces customers' QoS requirements into targets of web service design attributes and fulfills requirement driven web service design. It transfers the priority of necessity of QoS requirements into the priority of improvement of design specifications. Fuzzy set theory is used to deal with ambiguity and imprecision of subjective evaluation in the process of QFD. During the competitive evaluation and decision analysis of improvement target solutions, we introduce TCI to measure technical performance of web services and to compare them. Improvement target solutions with different goals are provided to make improved web service more competitive than any other similar web services on the market within the fewest efforts. ROI decision analysis diagram are provided to compare the efficiency of investments on different solutions. The optimization solutions and their comparison provide web service providers basis and support for decisionmaking of development and improvement of their web service products to win the market according to their technological and financial limitations. We use a web service system as an example to illustrate the approach and analyze the output of the approach to demonstrate its effectiveness, and the approach can be easily applied to practical situations. QoS is an important aspect of web service systems. With the increasing number of web services available on the Internet, web services with the same or similar function emerges inevitably. QoS becomes a decisive factor to distinguish the functionally same or similar web services. It affects the customers' selection and the success of service providers. To facilitate customers' service selection from functionally same or similar web services, QoS-based/aware web service selection approaches have been proposed. The web service selection approaches/algorithms rank the functionally same or similar services based on QoS requirements of the customers and returns the service with the highest rank to the customers as stated by [2] . The QoS-based service selection approaches can be generally classified into two categories according to the number of tasks. One is the service selection for a single task whereas the other is the service selection for each constituent task of the composite process Copyright c 2013 The Institute of Electronics, Information and Communication Engineers and search of an optimization combination of web services. Currently there are various QoS-based web service selection approaches. The comprehensive reviews of QoS-based web service selection techniques can be found in the surveys [2] - [4] .. However, as the paper [5] pointed out, current research on QoS of web services focuses on service users and the implementation stage, which means focusing on how to find the optimal services satisfying QoS requirements among existing web services on the network from the customer's perspective. It is also importance to how to design a web service to guarantee QoS requirements before making it available to the customers, especially for service providers. The paper [6] proposed a methodology WSMoD (Web Services Modeling Design), extending MDA (Model Driven Architecture) to address the QoS-based web service design explicitly. It adds a specific methodological step and extends PIM (Platform Independent Model) to define QoS/non-functional requirements. The research [5] incorporates QoS into the web service design at the development stage. It introduces a QoS meta-model by extending UML QoS profile to support QoS descriptions, and extends WSDL (Web Service Description Language) to include the proposed QoS metamodel. These approaches could assist web service providers to better understand what QoS of web services represents including QoS properties, their descriptions and dimensions, and they could ease web service providers to specify QoS. But how to design web services according to QoS metrics and how to determine service design specifications to meet QoS requirements are not addressed in these papers.. There are few web service design methods about how to determine target values of web service design attributes so that designed services have the ability to meet QoS requirements. Service design attributes are technical characteristics of services such as programming languages, data access protocols and database capacity which affect QoS. Only some design attributes of web services about network and communication e.g. bandwidth are analyzed in several papers [7] - [9] . They are not systematic to transfer QoS requirements into design attributes explicitly and quantitatively.. QFD, a quality methodology to transfer user demands into design quality, has been widely used in industries such as construction and aviation [1] , [10] , and also used in software engineering [11] , [12] , [24] . But researches on using QFD for developing emerging SOC systems are few [13] . Fuzzy theory has been applied to QFD to deal with a variety of qualitative and fuzzy input [14] , [15] . GA has been applied to optimization of technical characteristics in QFD [16] .. So we propose an approach to develop SOC-based web service systems using QFD. Based on technical information on competitive products, the approach searches optimal solutions of target values of web service design attributes in order to improved web services more competitive than any other service products within the lowest improvement efforts such as on cost. The solutions provide web service providers basis and support for development and improvement of their web service products.

O O O O O O B O O O B O O O O O O O O O O O O B I O O O O O O B O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O B O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O B I O O O O O O O O O O O B O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O B O O O O B I O O O O O O O O O O O B B O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O B O O O O O O O O O O O O O O O B O O O B O O O O O O O O O O O O O O O O B O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O B O O O O B O O O O O O O O O O O B O O B O O O O O O O O O O B I O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O B I O O O O B O O O O B I O O O O O O B I O O O O O O O O B O O O O O O O O O B I I O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O B I O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O B I O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O B I O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O B I O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O B O O B I O O O O O O O O B O O O O B O O O B O O O O B I O O O O O O B O O O O O B I O O O O O B O O O O O B O O O O O O O O O B I O O O B O O O O O O O O B O O O O O O O O O O B O O O O O O O O O O B I O O O O O O O O O B I O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O B O O O O O O O O O B O O O O O O O O O O B I O O B O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O B I O


RORSIM: a warship collision avoidance 3D simulation designed to complement existing Junior Warfare Officer training Abstract Royal Navy Junior Warfare Officers (JWO) undergo a comprehensive training package in order to prepare them to be officers of the watch. One aspect of this training relates to their knowledge of the 'Rules of the Road' or 'COLREGS'; the rules for the manoeuvring and signalling that approaching vessels make in order to avoid collision. The training and assessment exercises undertaken predominantly use non-interactive static materials. These do not exercise the required skill in reconciling information from maritime charts, radar displays and 'out-of-the-window' monitoring. Consequently, performance during assessment on the VR-based bridge simulator falls short. This paper describes The Rules of the Road SIMulator (RORSIM)-a proof of concept interactive 3D (i3D) simulator developed to bridge the training gap between classroom teaching and VR bridge simulator assessment. RORSIM's differentiation and its key functionality in terms of visualisaton, physics/interaction and game mechanics are influenced by the consideration of pedagogical learning models during requirements capture. This capture is formalised by a 'Training Gap Use Case'-a graphical viewpoint using the Universal Modelling Language which can assist developers in requirements capture and development of i3D tools for existing training programmes. Key functionality, initial JWO feedback and a planned pilot study design are reported. Interactive 3D (i3D) simulations are playing an increasingly important role in the training of Royal Navy (RN) personnel, from close-range weapons handling and vessel safety training (Stone and Rees 2002; Stone et al. 2010) to the bridge activities of Junior, or 'Initial' Warfare Officers (J/IWOs). A key challenge is to ensure that i3D simulations effectively complement and/or replace existing training tools and methods. For example, the RN's Close-Range Weapons Simulator (CRWS) demonstrated its value in bridging the training gap between classroom theory and field training through the use of inert weapons as the user interface (Stone and Rees 2002) . In contrast, mixed results in using speech recognition and synthesis technologies to command vessels were reported in the evaluation of the U.S. Navy's VESUB submarine deck trainer (Vincenzi et al. 2003) . Simulation design choices such as fidelity of visual presentation, control surfaces, artificial intelligence and physics must support and not hinder the aim of bridging the training gap between performance required and that achieved.. JWO's undertake a three year training programme. A key part prepares them for the role of Officer Of the Watch (OOW)-an officer situated on a warship bridge who contributes to control and navigation tasks. An important OOW task is to avoid collisions with other vessels-that is-develop the necessary situational awareness to enable the assessment of potential threats and to make and justify courses of action regarding the threats, through the safe manoeuvring of their own ship, the communication of their intentions to other vessels and, where appropriate, the issuing of warning signals via horn and/or light. This paper describes the development of the 'Rules Of the Road SIMulator' (RORSIM) which bridges the training gap between existing paper and computer-based methods. Desktop games-based trainers are seen in many military spheres as a cost-effective solution to enhance training quality and supplement more elaborate and expensive multi-screen VR simulator-based trainers. We argue that, to justify their existence, i3D desktop trainers should afford learning methods and assessment which differentiate them from mainstream mission or whole-system simulators in addition to replicating their function in a cost-effective manner. Precedently, to ensure a rapid development cycle, differentiation between training tools should be made explicit during the requirements capture phase. To develop RORSIM, we present a methodology for requirements capture which emphasises analysis of the training gap-the 'Training Gap Use Case'. This explicitly considers learning styles and existing training methods, which in turn assists the designer in developing system function and helps to speed up the iterative development cycle so that a fit-forpurpose design evolves.. While it is known that i3D can be effective training tools (e.g. Karadogan and Williams 2013; Harrington 2012; Smith and Ericson 2009) , such training will be most helpful when the tools are appropriately tailored to meet needs in the curriculum; the 'Training Gap Use Case' can be applied generally to both desktop and immersive 3D training applications. We also describe technical aspects of the system design and rationale to benefit the design of other similar systems, namely visualisation, interaction/physics and the use of game mechanics. Assessments of the tool's effectiveness are ongoing and beyond the scope of the present work.. In Sect. 2, the background to this project is discussed. Section 3 describes requirements capture process and introduces the Training Gap Use Case. Section 4 provides an overview of RORSIM and how the use case has influenced key functional aspects. Section 5 reports initial JWO trial feedback and outlines the planned pilot study design. Section 6 concludes the lessons learned and future work planned. The RORSIM concept capability research demonstrator is a desktop i3D part-task trainer which has been developed to address a specific training gap in applying COLREGS during RN JWO training. In this paper, we have detailed the methodology used to elicit requirements and thus beneficially influence functionality based around the extended UML use case which considers learning activities, styles and assessment methods-the Training Gap Use Case. This will benefit those seeking to formalise the value of introducing i3D desktop and immersive trainers into existing training programmes and can be applied retrospectively to existing training tools. We have outlined some technical details around simulation mechanics with specific focus on how the collision threat derived from radar data is quantified and fed back to students. This has potential to be used in the behaviour of autonomous vessels with a requirement to follow COLREGS.. Initial usability feedback gained from JWOs indicated broad acceptance of introducing RORSIM into training. The simulation also has potential for extension to support submarine fin-based navigation training at the RN Submarine School at HMS Raleigh and to train rules of engagement in theatre. We aim to measure the success and usage patterns of RORSIM across these different domains. Lessons learned during evaluation will also address fidelity appropriation to ensure successful training outcomes and will be reported in future studies.. RORSIM serves as an example in using rapid prototyping of an i3D simulation to plug a training gap in an existing training programme. By careful and formal consideration of the learning afforded by the simulation and how it complements existing teaching tools, its value to JWO training is better justified. Bespoke functionality inspired from the analysis can be rapidly realised by using open source game engine technology giving a high degree of control over levels of visual, task, logic and physics fidelity.

O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O


A novel numerical flux for the 3D Euler equations with general equation of state Please cite this article in press as: E. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. Here we extend the flux vector splitting approach recently proposed in (E F Toro and M E Vázquez-Cendón. Flux splitting schemes for the Euler equations. Computers and Fluids. Vol. 70, Pages 1-12, 2012). The scheme was originally presented for the 1D Euler equations for ideal gases and its extension presented in this paper is threefold: (i) we solve the three-dimensional Euler equations on general meshes; (ii) we use a general equation of state; and (iii) we achieve high order of accuracy in both space and time through application of the semi-discrete ADER methodology on general meshes. The resulting methods are systematically assessed for accuracy, robustness and efficiency on a carefully selected suite of test problems. Formal high accuracy is assessed through convergence rates studies for schemes of up to 4th order of accuracy in both space and time on unstructured meshes. Advanced computational methods for compressible flow rely on a first-order, monotone (for the scalar case) scheme as the building block. Though there seems to be an endless proliferation of publications aiming at the ultimate numerical flux, identifying a single scheme that is optimal for all cases of practical interest seems to be an impossible task. And hence the labouring goes on. Proposed methods fall essentially into two classes: upwind methods and centred or symmetric methods. In spite of their increased complexity, upwind methods tend to be preferred when having to resolve fine features, particularly those associated with intermediate characteristic fields. Then two possible choices are the Godunov approach [19] and associated Riemann solvers [38] , and the Flux Vector Splitting (FVS) approach. FVS schemes provide upwinding for fast waves at a lower computational effort and algorithm complexity than the Godunov approach with a good Riemann solver. Intermediate fields may also be well represented in the FVS approach if one adopts the more recent versions, such as that of Liou and Steffen [26] . Earlier FVS schemes, such as those reported in [34] , [43] and [45] , suffered from excessive numerical dissipation for contacts, shear waves and shear layers. For a review of FVS schemes see Chapter 8 of [38] . For background and reviews on the various classes of methods available see, for example, [18] , [38] and [25] .. In this paper we extend the flux vector splitting method recently proposed by Toro and Vázquez [42] . The scheme, called the TV flux here after, was first presented for the one-dimensional Euler equations, for ideal gases. A distinctive feature of the TV flux is that it separates completely advection terms from pressure terms, thus providing the possibility of taking advantage of their diverse speeds of propagation. Toro and Vázquez [42] also proposed a numerical approach that emerges from two separate systems produced by their flux vector splitting, the advection system and the pressure system. It turns out that the pressure system is hyperbolic and a very simple solution of the associated Riemann problem provides all the items required for flux evaluation. The resulting scheme proved to be simple and very robust, two ingredients that are usually difficult to reconcile.. Here we present a threefold extension of the TV flux: (i) we solve the threedimensional Euler equations on general meshes; (ii) we use a general equation of state (EOS); and (iii) we achieve high order of accuracy in both space and time through application of the fully-discrete ADER methodology in its finite volume setting. The resulting methods are systematically assessed for accuracy, robustness and efficiency on a carefully selected suit of test problems. Formal high accuracy is assessed through convergence rates studies. Schemes of up to 4th order of accuracy in both space and time on unstructured meshes are implemented and assessed.. The rest of this paper is structured as follows: Background material is briefly reviewed in Section 2. In Section 3 we extend the TV flux to the 3D Euler equations for general equations of state. In Section 4 we extend the methods to high order of accuracy on general meshes. Numerical results are shown in Section 5 and a summary and concluding remarks are found in Section 6. In this paper we have extended the TV flux of Toro and Vázquez, first present for the 1D Euler equations for ideal gases [42] , to the three-dimensional Euler equations with general equation of state. We have also extended their numerical method that relies entirely on the pressure system to find the numerical flux. Moreover, we have set the entire framework as the building block for the higherorder ADER methodology to compute high-order approximations in space and time on unstructured meshes. The schemes have been assessed on several carefully chosen test problems to demonstrate robustness, accuracy and efficiency, three key features of numerical methods. Formal high-order of accuracy on a problem with smooth solution has been demonstrated through a convergence rates study for schemes of up to fourth-order of accuracy in space and time on two-dimensional unstructured meshes. The approach can be implemented for any desired order of accuracy.. The TV flux offers a viable and attractive approach for computing solutions to the equations of compressible media. The scheme reconciles simplicity and efficiency with accurate resolution of fast and slow waves. The extensions presented here are set in the finite volume framework, but the whole building block can also be used in the ADER discontinuous Galerkin framework, in which the solution of the generalised Riemann problem allows arbitrary time and space accuracy. An attractive, potential extension of the TV flux concerns the full use of the total separation of advection from the pressure terms. This means separating slow advection waves from fast pressure waves, so that the former could be treated explicitly with CFL coefficient close to unity and the latter could be dealt with implicitly. Encouraging results in this direction are reported in the very recent work [8] , in which use is made of a staggered-mesh approach. The design of more sophisticated methods for implicit treatment of the pressure terms remains an open problem. Two approximate methods are compared against an exact Riemann solver: the present TV splitting scheme and the DOT scheme. It is seen that for the same Error = 0.02 the present TV scheme is 15 times faster than the DOT scheme and 9 times faster than the exact solver. Here we briefly review the background strictly necessary to present the scheme for the three-dimensional Euler equations.

O O O O O O O B I O B I I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O B I O O O O O O O B I I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O B I I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O B I O B I I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I


A biologically constrained model of the whole basal ganglia addressing the paradoxes of connections and selection Abstract The basal ganglia nuclei form a complex network of nuclei often assumed to perform selection, yet their individual roles and how they influence each other is still largely unclear. In particular, the ties between the external and internal parts of the globus pallidus are paradoxical, as anatomical data suggest a potent inhibitory projection between them while electrophysiological recordings indicate that they have similar activities. Here we introduce a theoretical study that reconciles both views on the intra-pallidal projection, by providing a plausible characterization of the relationship between the external and internal globus pallidus. Specifically, we developed a mean-field model of the whole basal ganglia, whose parameterization is optimized to respect best a collection of numerous anatomical and electrophysiological data. We first obtained models respecting all our constraints, hence anatomical and electrophysiological data on the intrapallidal projection are globally consistent. This model furthermore predicts that both aforementioned views about the intra-pallidal projection may be reconciled when this projection is weakly inhibitory, thus making it possible to support similar neural activity in both nuclei and for the entire basal ganglia to select between actions. Second, we predicts that afferent projections are substantially unbalanced towards the external segment, as it receives the strongest excitation from STN and the weakest inhibition from the striatum. Finally, our study strongly suggest that the intrapallidal connection pattern is not focused but diffuse, as this latter pattern is more efficient for the overall selection performed in the basal ganglia. The basal ganglia, a fundamental component of the learning and decision processes of the vertebrate brain, comprises several nuclei which are interconnected through a complex connectivity pattern whose corresponding functionalities are not deciphered yet and still a subject of intense studies. We conducted a computational study through a model of the whole basal ganglia in primate, realized with population coding (with mean-field models) and integrating detailed anatomical data like the size of dendritic fields, the respective number of neurons in the nuclei and the number of axonal varicosities. Such a large model requires the adjustment of more than 50 parameters, which we achieved using stochastic optimization heavily constrained by experimental data.. The main aim of this computational study is to investigate the relations between the external and internal parts of the globus pallidus inside the whole basal ganglia (BG). One key issue in BG understanding is the conciliation of anatomical data indicating that the external part of the globus pallidus exerts a direct inhibitory influence on its internal part, with electrophys-iological data showing that these nuclei have apparently similar activities (Mink 1996; Nambu 2008) . By studying this connection both from the anatomical and from the functional point of view, we aim to provide a further understanding of its place and role in the BG.. The second aim is to study more globally the physiology of the whole primate BG, which differs by several points from the rodent. An up-to-date view of the BG connections graph show that, in primate, nearly all the possible connections are present (Figure 1 ). Our goal is to provide a rigorous quantification of the strength of all the connections, that is consistent with as much data as possible from the literature.. The third and final aim is to contribute to the understanding of the function performed by the BG. The now classical theory that a selection is being performed in the BG (Mink 1996; Redgrave et al. 1999) has been illustrated by several computational models (e.g. Berns and Sejnowski (1994) ; Gurney et al. (2001) ; Frank (2006) ; Leblois et al. (2006) ; Humphries et al. (2006) ; Girard et al. (2008) ). The behavior of these models is highly dependent of their parameterizations, which have been obtained through fine-tuning under various arbitrary assumptions. By exploring the search space of plausible model parameterizations while making as few simplifications as possible, we aim to determine the extent to which the selection theory is effectively supported by an extensive collection of data on the primate BG. While we are using population level coding of the BG, our work aims at including detailed anatomical data that are usually used in modeling with spiking neurons, while still being able to respect electrophysiological data acquired in several monkey in vivo experiments. Moreover, our work aims to respect the different confidence ranges up to which the data are known. To do so, we formalize the modeling problem in terms of optimizing model fit to biological data, and to solve it we have developed an original methodology based on multi-objective optimization algorithms.. The objectives are dual in our approach. First, we want the design of our model to match detailed quantitative data concerning the anatomy and structure of the BG, in other words, we want it to be plausible by construction. Yet this objective is not sufficient by itself, as there is no telling how realistic a model will behave when simulated, no matter how good it looks on the paper. So, our second objective is that the model should exhibit a behavior in simulation as close as possible to the real BG. Considering that our level of modeling permits mainly to monitor firing rates of the nuclei, this second objective translates as the capability to fit to rates recorded in electrophysiological studies. These two objectives are similar to the construct and face validity concepts that have long been employed when discussing the validity of animal models in neuropathology (e.g. Willner 1984; Geyer and Markou 1995; Nestler and Hyman 2010) , which explains why we dubbed our objectives with these terms.. Finally, our level of modeling rests on data whose availability varies widely among the species. Given the wide amount of axonal tracing studies done in the monkey, we choose this species to gather our data. When not specified, the references of this paper concerns the macaque, and we explicitly mention it when we cite works on other primate genus or on other species. We studied the physiology and function of the BG through the design of models respecting as much as possible anatomical data (the construct objective) and electrophysiological data (the face objective). We focused in particular on the GPe and GPi/SNr, as their parameters were the most constrained by the electrophysiological data fitted (Kita et al. 2004; Tachibana et al. 2008) . The main outcomes of our study are as follow:. • Available anatomical and electrophysiological data on the GPe → GPi/SNr connection are consistent. The strength of this connection does not support opposed activities in the GPe and GPi/SNr, and a diffuse projection pattern is more efficient for the overall selection operated in BG. Fig. 10 For all optimized models, plot of difference of contrast values c i between diffuse and focused connectivity for the GPe → GPi/SNr connection for all directions. Positive values denote better selections in the diffuse case compared to the focused case, whereas negative values denote better deselections. This graph shows that for all models, a diffuse GPe → GPi/SNr projection leads both to a better selection of directions close to the preferred directions, and a better deselection of directions close to the opposite directions. See methods for the mathematical formulation of the indicator.. • Symmetry is not the rule in the strengths of the BG connections. In particular, both STN and MSN target more the GPe than the GPi/SNr. • Selection arises from the structure of the BG, without properly segregated direct and indirect pathways and without specific inputs from pyramidal tract neurons of the cortex.

O O O O O O O B I O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O B I O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O