Hierarchical control and optimisation of the Tennessee Eastman process

Based on integrated system optimisation and parameter estimation a method is described for on-line steady state optimisation which compensates for model-plant mismatch and solves a non-linear optimisation problem by iterating on a linear - quadratic representation. The method requires real process derivatives which are estimated using a dynamic identification technique. The utility of the method is demonstrated using a simulation of the Tennessee Eastman benchmark chemical process.

Autoregressive conditional kurtosis

This article proposes a new model for autoregressive conditional heteroscedasticity and kurtosis. Via a time-varying degrees of freedom parameter, the conditional variance and conditional kurtosis are permitted to evolve separately. The model uses only the standard Student’s t-density and consequently can be estimated simply using maximum likelihood. The method is applied to a set of four daily financial asset return series comprising U.S. and U.K. stocks and bonds, and significant evidence in favor of the presence of autoregressive conditional kurtosis is observed. Various extensions to the basic model are proposed, and we show that the response of kurtosis to good and bad news is not significantly asymmetric.

Aligning business and IT from multi-level learning perspectives

Business and IT alignment is increasingly acknowledged as a key for organisational performance. However, alignment research lack to mechanisms that enable for on-going process with multi-level effects. Multi-level learning allows on-going effectiveness through development of the organisation and improved quality of business and IT strategies. In particular, exploration and exploitation enable effective process of alignment across dynamic multi-level of learning. Hence, this paper proposes a conceptual framework that links multi-level learning and business-IT strategy through the concept of exploration and exploitation, which considers short-term and long-term alignment together to address the challenges of strategic alignment faced in sustaining organisational performance.

Winckelmann and the invention of antiquity: history and aesthetics in the age of Altertumswissenschaft

This volume provides a new perspective on the emergence of the modern study of antiquity, Altertumswissenschaft, in eighteenth-century Germany through an exploration of debates that arose over the work of the art historian Johann Joachim Winckelmann between his death in 1768 and the end of the century. This period has long been recognised as particularly formative for the development of modern classical studies, and over the past few decades has received increased attention from historians of scholarship and of ideas. Winckelmann's eloquent articulation of the cultural and aesthetic value of studying the ancient Greeks, his adumbration of a new method for studying ancient artworks, and his provision of a model of cultural-historical development in terms of a succession of period styles, influenced both the public and intra-disciplinary self-image of classics long into the twentieth century. Yet this area of Winckelmann's Nachleben has received relatively little attention compared with the proliferation of studies concerning his importance for late eighteenth-century German art and literature, for historians of sexuality, and his traditional status as a 'founder figure' within the academic disciplines of classical archaeology and the history of art. Harloe restores the figure of Winckelmann to classicists' understanding of the history of their own discipline and uses debates between important figures, such as Christian Gottlob Heyne, Friedrich August Wolf, and Johann Gottfried Herder, to cast fresh light upon the emergence of the modern paradigm of classics as Altertumswissenschaft: the multi-disciplinary, comprehensive, and historicizing study of the ancient world.

The contributions of domain-general and numerical factors to third-grade arithmetic skills and mathematical learning disability

Explanations of the marked individual differences in elementary school mathematical achievement and mathematical learning disability (MLD or dyscalculia) have involved domain-general factors (working memory, reasoning, processing speed and oral language) and numerical factors that include single-digit processing efficiency and multi-digit skills such as number system knowledge and estimation. This study of third graders (N = 258) finds both domain-general and numerical factors contribute independently to explaining variation in three significant arithmetic skills: basic calculation fluency, written multi-digit computation, and arithmetic word problems. Estimation accuracy and number system knowledge show the strongest associations with every skill and their contributions are both independent of each other and other factors. Different domain-general factors independently account for variation in each skill. Numeral comparison, a single digit processing skill, uniquely accounts for variation in basic calculation. Subsamples of children with MLD (at or below 10th percentile, n = 29) are compared with low achievement (LA, 11th to 25th percentiles, n = 42) and typical achievement (above 25th percentile, n = 187). Examination of these and subsets with persistent difficulties supports a multiple deficits view of number difficulties: most children with number difficulties exhibit deficits in both domain-general and numerical factors. The only factor deficit common to all persistent MLD children is in multi-digit skills. These findings indicate that many factors matter but multi-digit skills matter most in third grade mathematical achievement.

Parallel editing, multi-positionality and maximalism: cosmopolitan effects as explored in some art works by Melanie Jackson and Vivienne Dick

Garfield produces a critique of neo-minimalist art practice by demonstrating how the artist Melanie Jackson’s Some things you are not allowed to send around the world (2003 and 2006) and the experimental film-maker Vivienne Dick’s Liberty’s booty (1980) – neither of which can be said to be about feeling ‘at home’ in the world, be it as a resident or as a nomad – examine global humanity through multi-positionality, excess and contingency, and thereby begin to articulate a new cosmopolitan relationship with the local – or, rather, with many different localities – in one and the same maximalist sweep of the work. ‘Maximalism’ in Garfield’s coinage signifies an excessive overloading (through editing, collage, and the sheer density of the range of the material) that enables the viewer to insert themselves into the narrative of the work. In the art of both Jackson and Dick Garfield detects a refusal to know or to judge the world; instead, there is an attempt to incorporate the complexities of its full range into the singular vision of the work, challenging the viewer to identify what is at stake.

Benchmarks and the accuracy of GARCH model estimation

This paper reviews nine software packages with particular reference to their GARCH model estimation accuracy when judged against a respected benchmark. We consider the numerical consistency of GARCH and EGARCH estimation and forecasting. Our results have a number of implications for published research and future software development. Finally, we argue that the establishment of benchmarks for other standard non-linear models is long overdue.

An integrated multi-stage model of knowledge management in international joint ventures: identifying a trigger for knowledge exploration and knowledge harvest

This paper examines the evolution of knowledge management from the initial knowledge migration stage, through adaptation and creation, to the reverse knowledge migration stage in international joint ventures (IJVs). While many studies have analyzed these stages (mostly focusing on knowledge transfer), we investigated the path-dependent nature of knowledge flow in IJVs. The results from the empirical analysis based on a survey of 136 Korean parent companies of IJVs reveal that knowledge management in IJVs follows a sequential, multi-stage process, and that the knowledge transferred from parents to IJVs must first be adapted within its new environment before it reaches the creation stage. We also found that only created knowledge is transferred back to parents.

Rapid qualitative and quantitative analysis of proanthocyanidin oligomers and polymers by UPLC-MS/MS.

This paper presents the development of a rapid method with ultraperformance liquid chromatography–tandem mass spectrometry (UPLC-MS/MS) for the qualitative and quantitative analyses of plant proanthocyanidins directly from crude plant extracts. The method utilizes a range of cone voltages to achieve the depolymerization step in the ion source of both smaller oligomers and larger polymers. The formed depolymerization products are further fragmented in the collision cell to enable their selective detection. This UPLC-MS/MS method is able to separately quantitate the terminal and extension units of the most common proanthocyanidin subclasses, that is, procyanidins and prodelphinidins. The resulting data enable (1) quantitation of the total proanthocyanidin content, (2) quantitation of total procyanidins and prodelphinidins including the procyanidin/prodelphinidin ratio, (3) estimation of the mean degree of polymerization for the oligomers and polymers, and (4) estimation of how the different procyanidin and prodelphinidin types are distributed along the chromatographic hump typically produced by large proanthocyanidins. All of this is achieved within the 10 min period of analysis, which makes the presented method a significant addition to the chemistry tools currently available for the qualitative and quantitative analyses of complex proanthocyanidin mixtures from plant extracts.

Complex-valued B-spline neural networks for modeling and inverting Hammerstein systems

Many communication signal processing applications involve modelling and inverting complex-valued (CV) Hammerstein systems. We develops a new CV B-spline neural network approach for efficient identification of the CV Hammerstein system and effective inversion of the estimated CV Hammerstein model. Specifically, the CV nonlinear static function in the Hammerstein system is represented using the tensor product from two univariate B-spline neural networks. An efficient alternating least squares estimation method is adopted for identifying the CV linear dynamic model’s coefficients and the CV B-spline neural network’s weights, which yields the closed-form solutions for both the linear dynamic model’s coefficients and the B-spline neural network’s weights, and this estimation process is guaranteed to converge very fast to a unique minimum solution. Furthermore, an accurate inversion of the CV Hammerstein system can readily be obtained using the estimated model. In particular, the inversion of the CV nonlinear static function in the Hammerstein system can be calculated effectively using a Gaussian-Newton algorithm, which naturally incorporates the efficient De Boor algorithm with both the B-spline curve and first order derivative recursions. The effectiveness of our approach is demonstrated using the application to equalisation of Hammerstein channels.

The late Roman field army in Northern Britain? Mobility, material culture and multi-isotope analysis at Scorton (N. Yorks)

At Hollow Banks Quarry, Scorton, located just north of Catterick (N Yorks.), a highly unusual group of 15 late Roman burials was excavated between 1998 and 2000. The small cemetery consists of almost exclusively male burials, dated to the fourth century. An unusually large proportion of these individuals was buried with crossbow brooches and belt fittings, suggesting that they may have been serving in the late Roman army or administration and may have come to Scorton from the Continent. Multi-isotope analyses (carbon, nitrogen, oxygen and strontium) of nine sufficiently well-preserved individuals indicate that seven males, all equipped with crossbow brooches and/or belt fittings, were not local to the Catterick area and that at least six of them probably came from the European mainland. Dietary (carbon and nitrogen isotope) analysis only of a tenth individual also suggests a non-local origin. At Scorton it appears that the presence of crossbow brooches and belts in the grave was more important for suggesting non-British origins than whether or not they were worn. This paper argues that cultural and social factors played a crucial part in the creation of funerary identities and highlights the need for both multi-proxy analyses and the careful contextual study of artefacts.

A tale of two Montreal communities: parental perspectives on their children's multi-lingual and multi-literate development

This comparative inquiry examines the multi-/bilingual nature and cultural diversity of two distinctly different linguistic and ethnic communities in Montreal – English speakers and Chinese speakers – with a focus on the multi/bilingual and multi/biliterate development of children from these two communities who attend French-language schools, by choice in one case and by law in the other. In both of these communities, children traditionally achieve academic success. The authors approach this investigation from the perspective of the parents’ aspirations and expectations for, and their support of and involvement in, their children’s education. These two communities share key similarities and differences that, when considered together, help to clarify a number of issues involving multi/biliteracy development, socio-economic and linguistic capital, minority/majority language status, mother-tongue support, home–school continuities, and linguistic identity.

Multi-sensory treatment for children with developmental motor speech disorders

What this paper adds? What is already known on the subject? Multi-sensory treatment approaches have been shown to impact outcome measures positively, such as accuracy of speech movement patterns and speech intelligibility in adults with motor speech disorders, as well as in children with apraxia of speech, autism and cerebral palsy. However, there has been no empirical study using multi-sensory treatment for children with speech sound disorders (SSDs) who demonstrate motor control issues in the jaw and orofacial structures (e.g. jaw sliding, jaw over extension, inadequate lip rounding/retraction and decreased integration of speech movements). What this paper adds? Findings from this study indicate that, for speech production disorders where both the planning and production of spatiotemporal parameters of movement sequences for speech are disrupted, multi-sensory treatment programmes that integrate auditory, visual and tactile–kinesthetic information improve auditory and visual accuracy of speech production. The training (practised in treatment) and test words (not practised in treatment) both demonstrated positive change in most participants, indicating generalization of target features to untrained words. It is inferred that treatment that focuses on integrating multi-sensory information and normalizing parameters of speech movements is an effective method for treating children with SSDs who demonstrate speech motor control issues.

Efficiency of wear and decalcification technique for estimating the age of estuarine dolphin Sotalia guianensis

Most techniques used for estimating the age of Sotalia guianensis (van B,n,den, 1864) (Cetacea; Delphinidae) are very expensive, and require sophisticated equipment for preparing histological sections of teeth. The objective of this study was to test a more affordable and much simpler method, involving of the manual wear of teeth followed by decalcification and observation under a stereomicroscope. This technique has been employed successfully with larger species of Odontoceti. Twenty-six specimens were selected, and one tooth of each specimen was worn and demineralized for growth layers reading. Growth layers were evidenced in all specimens; however, in 4 of the 26 teeth, not all the layers could be clearly observed. In these teeth, there was a significant decrease of growth layer group thickness, thus hindering the layers count. The juxtaposition of layers hindered the reading of larger numbers of layers by the wear and decalcification technique. Analysis of more than 17 layers in a single tooth proved inconclusive. The method applied here proved to be efficient in estimating the age of Sotalia guianensis individuals younger than 18 years. This method could simplify the study of the age structure of the overall population, and allows the use of the more expensive methodologies to be confined to more specific studies of older specimens. It also enables the classification of the calf, young and adult classes, which is important for general population studies.

A Robust, Fully Adaptive Hybrid Level-Set/Front-Tracking Method for Two-Phase Flows with an Accurate Surface Tension Computation

We present a variable time step, fully adaptive in space, hybrid method for the accurate simulation of incompressible two-phase flows in the presence of surface tension in two dimensions. The method is based on the hybrid level set/front-tracking approach proposed in [H. D. Ceniceros and A. M. Roma, J. Comput. Phys., 205, 391400, 2005]. Geometric, interfacial quantities are computed from front-tracking via the immersed-boundary setting while the signed distance (level set) function, which is evaluated fast and to machine precision, is used as a fluid indicator. The surface tension force is obtained by employing the mixed Eulerian/Lagrangian representation introduced in [S. Shin, S. I. Abdel-Khalik, V. Daru and D. Juric, J. Comput. Phys., 203, 493-516, 2005] whose success for greatly reducing parasitic currents has been demonstrated. The use of our accurate fluid indicator together with effective Lagrangian marker control enhance this parasitic current reduction by several orders of magnitude. To resolve accurately and efficiently sharp gradients and salient flow features we employ dynamic, adaptive mesh refinements. This spatial adaption is used in concert with a dynamic control of the distribution of the Lagrangian nodes along the fluid interface and a variable time step, linearly implicit time integration scheme. We present numerical examples designed to test the capabilities and performance of the proposed approach as well as three applications: the long-time evolution of a fluid interface undergoing Rayleigh-Taylor instability, an example of bubble ascending dynamics, and a drop impacting on a free interface whose dynamics we compare with both existing numerical and experimental data.