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One of the most important research topics in the area of Intelligent Manufacture Systems (IMS) is the automatic detection of tool breakage, wear of chipping during the cutting process. Sensor-based techniques are available for cutting force measurements, but there are drawbacks in this approach in cost and idle times. This work proposes a sensorless monitoring system for tool monitoring in order to detect breakage and chipping by exploiting the wavelet transform and a neural network. Previous works have made use of these tools for monitoring several machining parameters, but we propose an integrated low-cost approach to detect quickly the changes in the tool integrity for monitoring. The system output produces an accurate detection of the tool integrity that enables the system to prevent damage due to tool breakage. This approach allows for an industrial solution to be developed.  相似文献   
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The catalytic activity of different heterogeneous sulfonic acid-modified catalysts has been assayed in the simultaneous esterification of FFA and transesterification of triglycerides of crude palm oil (FFA content of 5.6 wt%) with methanol, demonstrating the applicability of this kind of acid solids to the one-step production of biodiesel from FFA-containing vegetable oils. The yield towards fatty acid methyl esters (FAMEs) obtained over these acid materials is enhanced when increasing the acid strength of the catalytic site. Likewise, the use of mesostructured supports has been shown as a factor improving the catalytic performance as compared with macroporous sulfonic acid-based resins, likely due to an enhancement of the mass transfer rates of large molecules, such as triglycerides, within the catalyst structure. Thus, the combination of the open mesoporous structure of a SBA-15 silica support with relatively strong arenesulfonic acid sites leads to a material able to yield high conversion of triglycerides and free fatty acids. Furthermore, a study on the transesterification reaction of crude palm oil with methanol through a surface response analysis has provided as optimal conditions the following: temperature 160 °C, catalyst loading 5.1 wt% referred to the amount of palm oil, and methanol to oil molar ratio 30. Under these conditions, almost 90% of the starting oil is converted to FAME after reacting for just 2 h of reaction. Likewise, surface response analysis has evidenced a strong interaction between temperature and methanol to oil ratio.  相似文献   
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Among the different types of stimuli‐responsive polymers, conjugated polymers reveal unique multiresponsive behavior. In this work, the synthesis and characterization of new functional poly(3,4‐ethylenedioxythiophenes) (PEDOT) bearing imidazolium ionic‐liquid moieties (PEDOT‐Im) is reported. PEDOT‐Im polymers show multiresponsive properties to a variety of stimuli, such as temperature, pH, oxidative doping, and presence of anions. These stimuli provoke different changes in PEDOT‐Im, such as changes in color, oxidation state, and, wetting behavior. In all cases, a reversible effect is observed, and the polymers reveal responsive properties in solution as well as in the form of thin films. Whereas sensitiveness to pH and oxidative doping are known phenomena for other PEDOT derivatives, responsiveness to temperature and to anions is a unique property of PEDOT‐Im. The anion exchange is further investigated by means of the Quartz Crystal Microbalance with dissipation. Anion exchanges induce fast, adjustable, and reversible contact angle changes between 24° and 107°. As a potential application, surfaces with switchable wettability triggered by anion solutions are prepared by spin‐coating PEDOT‐Im films onto different substrates.  相似文献   
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Most of the studies about the macroeconomic consequences of oil price shocks have been focused on US aggregate data. In contrast to these studies, this paper empirically assesses the dynamic effect of oil price shocks on the output of the main manufacturing industries in six OECD countries. The pattern of responses to an oil price shock by industrial output is diverse across the four European Monetary Union (EMU) countries under consideration (France, Germany, Italy, and Spain), but broadly similar in the UK and the US. Moreover, evidence on cross-industry heterogeneity of oil shock effects within the EMU countries is also reported.  相似文献   
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Interactive Digital TV opens new learning possibilities where new forms of education are needed. On the one hand, the combination of education and entertainment is essential to boost the participation of viewers in TV learning (t-learning), overcoming their typical passiveness. On the other hand, researchers broadly agree that in order to prevent the learner from abandoning the learning experience, it is necessary to take into account his/her particular needs and preferences by means of a personalized experience. Bearing this in mind, this paper introduces a new approach to the conception of personalized t-learning: edutainment and entercation experiences. These experiences combine TV programs and learning contents in a personalized way, with the aim of using the playful nature of TV to make learning more attractive and to engage TV viewers in learning. This paper brings together our work in constructing edutainment/entercation experiences by relating TV and learning contents. Taking personalization one step further, we propose the adaptation of learning contents by defining A-SCORM (Adaptive-SCORM), an extension of the ADL SCORM standard. Over and above the adaptive add-ons, this paper focuses on two fundamental entities for the proposal: (1) an Intelligent Tutoring System, called T-MAESTRO, which constructs the t-learning experiences by applying semantic knowledge about the t-learners; and (2) the authoring tool which allow teachers to create adaptive courses with a minimal technical background.
Manuel Ramos-CabrerEmail:

Marta Rey-López   is an assistant professor and a Ph.D. student in the Department of Telematics Engineering at the University of Vigo, where she received her degree in Telecommunication Engineering in 2004. Since 2004 she belongs to the Interactive Digital TV Lab, her research interests focus on the combination of TV programs and interactive applications for TV to provide distance education through this medium. Her more recent research deals with the application of Web 2.0 technologies to establish the relationships between those two different types of contents. Rebeca P. Díaz-Redondo   is an associate professor in the Department of Telematics Engineering at the University of Vigo, where she received her Ph.D. in Computer Science in 2002, in the field of Software Engineering. She is a member of the Interactive Digital TV Lab, and her major research interests are interactive applications for TV as well as how they interact with the smart home environment. Ana Fernández-Vilas   received her Ph.D. in Computer Science from the University of Vigo in 2002, in the field of Software Engineering. Since 1997, she is an associate professor in the Department of Telematics Engineering (University of Vigo). She is engaged in web services technologies and ubiquitous computing environments, being a member of the Interactive Digital TV Lab. José J. Pazos-Arias   received his Ph.D. in Computer Science from the Department of Telematics Engineering the Polytechnic University of Madrid in 1995 in the field of Software Engineering. He is currently the head of the Networking and Software Engineering Group at the University of Vigo, which is currently involved with projects on middleware and applications for Interactive Digital TV that include learning through TV, recommendation of TV programmes, personalised advertising and t-government. Martín López-Nores   is an assistant professor in the Department of Telematics Engineering of the University of Vigo since 2003, where he received his Ph.D. in Computer Science in 2006 in the field of Software Engineering techniques and its application to the field of Interactive Digital TV. He is a member of the Interactive Digital TV Lab, where he is especially interested in personalization of advertising and education. Jorge García-Duque   is an associate professor in the Department of Telematics Engineering at the University of Vigo, where he received his Ph.D. in Computer Science in 2000, in the field of Software Engineering. His major research interests are related to the development of new software methodologies and services for Interactive Digital TV. Alberto Gil-Solla   is an associate professor in the Department of Telematics Engineering at the University of Vigo, and a member of the Software Engineering Research Group. He received his Ph.D. in Computer Science from the University of Vigo in 2000, in the field of Software Engineering. He is involved with different aspects of middleware design and interactive multimedia services. Manuel Ramos-Cabrer   received his Ph.D. in Telematics from the University of Vigo in 2000, in the field of Software Engineering, where he is an associate professor in Telematics Engineering since 2001. His research topics are Interactive Digital TV concentrating on recommender systems, integration with smart home environments and interactive applications design and development.   相似文献   
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Due to the increase of XML-based applications, XML schema design has become an important task. One approach is to consider conceptual schemas as a basis for generating XML documents compliant to consensual information of specific domains. However, the conversion of conceptual schemas to XML schemas is not a straightforward process and inconvenient design decisions can lead to a poor query processing on XML documents generated. This paper presents a conversion approach which considers data and query workload estimated for XML applications, in order to generate an XML schema from a conceptual schema. Load information is used to produce XML schemas which can respond well to the main queries of an XML application. We evaluate our approach through a case study carried out on a native XML database. The experimental results demonstrate that the XML schemas generated by our methodology contribute to a better query performance than related approaches.
Ronaldo dos Santos MelloEmail:
  相似文献   
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