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Relevant Problems (relevant + problem)
Selected AbstractsComposition cascade control for chemical reactorsINTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL, Issue 13 2002Jose Alvarez-Ramirez Abstract Eventhough the composition control of chemical reactors is an old, widely studied, and still relevant problem in chemical process control, it still presents some aspects that remain unexplored or unresolved. For instance, a unifying approach is needed to systematize the existing ad hoc controller constructions, to rigorously explain their remarkable robustness property, and to explore the possibility of improving their construction and functioning. In this paper, some aspects of these control problems are addressed by resorting to recently developed approaches in constructive non-linear control, yielding a systematic controller construction coupled to a simple tuning scheme that can be executed with standard tuning rules, a closed-loop stability criterion, and an explanation of the closed-loop dynamics behaviour. Specifically, a linear cascade (master/slave) control configuration is proposed, which leads to global internal stability of the controlled system with asymptotic regulation of the output-stream composition about a given desired setpoint. A simulation example is used to illustrate the results. Copyright © 2002 John Wiley & Sons, Ltd. [source] On peptide de novo sequencing: a new approach,JOURNAL OF PEPTIDE SCIENCE, Issue 4 2005Dr Renato Bruni Abstract A procedure is presented for the automatic determination of the amino acid sequence of peptides by processing data obtained from mass spectrometry analysis. This is a basic and relevant problem in the field of proteomics. Furthermore, it has an even higher conceptual and applicative interest in peptide research, as well as in other connected fields. The analysis does not rely on known protein databases, but on the computation of all amino acid sequences compatible with the given spectral data. By formulating a mathematical model for such combinatorial problems, the structural limitations of known methods are overcome, and efficient solution algorithms can be developed. The results are very encouraging both from the accuracy and computational points of view. Copyright © 2004 European Peptide Society and John Wiley & Sons, Ltd. [source] Dynamics of Foaming of Polystyrene ParticlesMACROMOLECULAR SYMPOSIA, Issue 1 2006Gabriela Salejova Abstract September 24, 2006 Summary: In this work, we address the industrially relevant problem of the foaming of expandable polystyrene (PS) impregnated by pentane as a traditional down-stream processing in the suspension polymerization of styrene. Once the polystyrene foam is formed by means of a proper foaming agent, e.g., pentane or fluoro- or chloro-hydrocarbons, the blowing agent diffuses out from the cellular structure. Environmental efforts call for the reduced consumption of blowing agents. The dynamics of foaming of polystyrene particles was recorded video-microscopically in our laboratory as the sequence of images of expanding particle located in the small pressure cell placed under the microscope with sufficient depth of focus. The amount of pentane sorbed in PS was controlled by the length of the impregnation period and was determined independently by gravimetric measurements. Strong dependence of the structure of the produced foam and of the foaming dynamics on the amount of sorbed pentane, temperature and particle size is reported and explanations for some observed foaming phenomena are provided. [source] A current overview of consumer neuroscienceJOURNAL OF CONSUMER BEHAVIOUR, Issue 4-5 2008Mirja Hubert The emerging discipline of neuroeconomics employs methods originally used in brain research for investigating economic problems, and furthers the advance of integrating neuroscientific findings into the economic sciences. Neuromarketing or consumer neuroscience is a sub-area of neuroeconomics that addresses marketing relevant problems with methods and insights from brain research. With the help of advanced techniques of neurology, which are applied in the field of consumer neuroscience, a more direct view into the "black box" of the organism should be feasible. Consumer neuroscience, still in its infancy, should not be seen as a challenge to traditional consumer research, but constitutes a complementing advancement for further investigation of specific decision-making behavior. The key contribution of this paper is to suggest a distinct definition of consumer neuroscience as the scientific proceeding, and neuromarketing as the application of these findings within the scope of managerial practice. Furthermore, we aim to develop a foundational understanding of the field, moving away from the derisory assumption that consumer neuroscience is about locating the "buy button" in the brain. Against this background the goal of this paper is to present specific results of selected studies from this emerging discipline, classified according to traditional marketing-mix instruments such as product, price, communication, and distribution policies, as well as brand research. The paper is completed by an overview of the most prominent brain structures relevant for consumer neuroscience, and a discussion of possible implications of these insights for economic theory and practice. Copyright © 2008 John Wiley & Sons, Ltd. [source] Information-centered research for large-scale analyses of new information sourcesJOURNAL OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE AND TECHNOLOGY, Issue 9 2008Mike Thelwall New mass publishing genres, such as blogs and personal home pages provide a rich source of social data that is yet to be fully exploited by the social sciences and humanities. Information-centered research (ICR) not only provides a genuinely new and useful information science research model for this type of data, but can also contribute to the emerging e-research infrastructure. Nevertheless, ICR should not be conducted on a purely abstract level, but should relate to potentially relevant problems. [source] Drug use investigation (DUI) and prescription-event monitoring in Japan (J-PEM),PHARMACOEPIDEMIOLOGY AND DRUG SAFETY, Issue 7 2001Katsutoshi Tanaka BSc Abstract Objective To present ethical issues and relevant problems in observational studies of drug safety in Japan. Methods The Pharmaceutical Affairs Law, associated ordinances, and notifications relevant to Drug Use Investigations (DUIs), and published documents for two pilot studies of prescription-event monitoring in Japan (J-PEM) were examined, particularly with regard to the protection of privacy. Information relevant to the proposed legislation intended to protect personal information and proposed guidelines on ethical issues in epidemiological studies were also collected. Results and Conclusion The formal studies inaugurated as the ,side-effect investigations' in the late 1960s and replaced by those of the DUI in 1980 have been conducted by drug manufacturers, in accordance with the Pharmaceutical Affairs Law. The first pilot study of J-PEM was started in 1997 and the second one is currently operated under a Health Sciences Research grant, supported by the Ministry of Health and Welfare. Those observational studies have been conducted while maintaining the confidentiality of personal data, but without requiring either approval by institutional ethics boards or informed consent from patients. However, according to the Pharmaceutical Affairs Law, those involved in postmarketing surveillance studies must protect the privacy of study subjects and those who break this rule may be subject to penalties. Ethical issues associated with pharmacoepidemiological studies will be clearly determined in Japan before the end of 2001 when the law designed to protect personal information will be introduced and official guidelines on ethical issues in epidemiological studies will have come into effect. Copyright © 2001 John Wiley & Sons, Ltd. [source] Health-related quality of life assessment after breast reconstruction,BRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 6 2009S. Potter Background: Health-related quality of life (HRQL) is an important outcome following breast reconstruction. This study evaluated current methods of HRQL assessment in patients undergoing latissimus dorsi breast reconstruction, hypothesizing that early surgical morbidity would be reflected by poorer HRQL scores. Methods: Patients completed the European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30 and breast module (QLQ-BR23), the Functional Assessment of Cancer Therapy (FACT) general measure, and breast module and arm subscale (FACT-B + 4), and the Body Image Scale and Hospital Anxiety and Depression Scale (HADS) 3 months after surgery. They also reported additional HRQL problems not included in the questionnaires. HRQL scores were compared between patients with and without early surgical morbidity. Results: Sixty women completed the questionnaires, of whom 25 (42 per cent) experienced complications. All EORTC and FACT subscale and HADS scores were similar in patients with or without morbidity. Women with complications were twice as likely to report feeling less feminine and dissatisfied with the appearance of their scar than those without problems. Thirty-two women (53 per cent) complained of problems not covered by the questionnaires, most commonly donor-site morbidity. Conclusion: Existing HRQL instruments are not sufficiently sensitive to detect clinically relevant problems following breast reconstruction. Copyright © 2009 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd. [source] Sequence Encoders Enable Large-Scale Lexical Modeling: Reply to Bowers and Davis (2009)COGNITIVE SCIENCE - A MULTIDISCIPLINARY JOURNAL, Issue 7 2009Daragh E. Sibley Abstract Sibley, Kello, Plaut, and Elman (2008) proposed the sequence encoder as a model that learns fixed-width distributed representations of variable-length sequences. In doing so, the sequence encoder overcomes problems that have restricted models of word reading and recognition to processing only monosyllabic words. Bowers and Davis (2009) recently claimed that the sequence encoder does not actually overcome the relevant problems, and hence it is not a useful component of large-scale word-reading models. In this reply, it is noted that the sequence encoder has facilitated the creation of large-scale word-reading models. The reasons for this success are explained and stand as counterarguments to claims made by Bowers and Davis. [source] | ||||||||||