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991.
Agnes Romero Inmaculada Aguado Marta Yebra 《International journal of remote sensing》2013,34(2):396-414
This work applies remote sensing techniques to estimate dry matter (DM) content in tree leaves. Two methods were used to estimate DM content: a normalized index obtained from the radiative transfer model (RTM) leaf optical properties spectra (PROSPECT) in direct mode and the inversion of the PROSPECT model. The data were obtained from the Leaf Optical Properties Experiment 93 (LOPEX93) database, and only 11 species were used in this study. The species selection was based mainly on the availability of data on fresh and dry samples. The estimation of DM content was obtained from an exponential function that correlated the values of the index proposed, (R2305???R1495)/(R2305?+?R1495), against the DM content of fresh and dry leaf samples. The determination coefficient obtained (r 2?=?0.672) was higher than the coefficient obtained from the inversion of the PROSPECT model (r 2?=?0.507). The data set used to validate the normalized index was provided by the Accelerated Canopy Chemistry Program (ACCP). The determination coefficient between the values obtained from ACCP data and the values estimated for the normalized index was r 2?=?0.767. 相似文献
992.
Kevin Doolin Robert Mullins Rafael Morón Abad Marta García Moreno Telma Mota Babak A. Farshchian Miguel Gómez 《Journal of Network and Systems Management》2008,16(1):92-112
Natural communication among people happens in flexible ways and is strongly affected by the users’ situation (such as communication
tools available, user’s location, and user’s preferences). This situation or context information is seldom used to initiate
communication sessions among users. Current communication systems are indifferent about users’ context, often require time
consuming manual configurations and often result in conferencing tools not being easily accessible when needed. This leads
to lower adoption of innovative communications services. IMS SIP (IP Multimedia Subsystem, Session Initiation Protocol) sessions
allow users to access the session from different points of contact (home, office, etc.), however, IMS still requires a prior
knowledge of all SIP components that might be used in a SIP session. Furthermore, IMS makes limited use of context information
(mainly user-defined availability). To address these issues our research approach combines techniques from pervasive computing
with IMS networking principles to facilitate compositions of communication sessions based on users’ context. We propose a
platform and APIs for pervasive application development support to allow greater intelligence in IMS applications. We additionally
provide mechanisms for IMS applications to apply their intelligence to the configuration of physical devices and web resources
used to set up a conference. The innovations proposed in this paper are: (1) A new standard for intelligent IMS-based conferencing
applications. (2) Application Development Interfaces (APIs) for a platform for pervasive computing. (3) An architecture for
a pervasive IMS platform.
相似文献
Kevin DoolinEmail: |
993.
T-MAESTRO and its authoring tool: using adaptation to integrate entertainment into personalized t-learning 总被引:1,自引:1,他引:0
Marta Rey-López Rebeca P. Díaz-Redondo Ana Fernández-Vilas José J. Pazos-Arias Martín López-Nores Jorge García-Duque Alberto Gil-Solla Manuel Ramos-Cabrer 《Multimedia Tools and Applications》2008,40(3):409-451
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.
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
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
994.
995.
Marta Kwiatkowska Gethin Norman David Parker Jeremy Sproston 《Formal Methods in System Design》2006,29(1):33-78
Probabilistic timed automata, a variant of timed automata extended with discrete probability distributions, is a modelling formalism suitable for describing formally both nondeterministic and probabilistic aspects of real-time systems, and is amenable to model checking against probabilistic timed temporal logic properties. However, the previously developed verification algorithms either suffer from high complexity, give only approximate results, or are restricted to a limited class of properties. In the case of classical (non-probabilistic) timed automata it has been shown that for a large class of real-time verification problems correctness can be established using an integral model of time (digital clocks) as opposed to a dense model of time. Based on these results we address the question of under what conditions digital clocks are sufficient for the performance analysis of probabilistic timed automata and show that this reduction is possible for an important class of systems and properties including probabilistic reachability and expected reachability. We demonstrate the utility of this approach by applying the method to the performance analysis of three probabilistic real-time protocols: the dynamic configuration protocol for IPv4 link-local addresses, the IEEE 802.11 wireless local area network protocol and the IEEE 1394 FireWire root contention protocol.
相似文献
Jeremy SprostonEmail: |
996.
Apriori算法在红外光谱数据挖掘中的应用 总被引:1,自引:0,他引:1
简要地介绍了在大规模数据库中挖掘关联规则的Apriori算法 ,给出了红外光谱数据库知识发现的空间表示方法 ,并根据红外光谱数据挖掘的特点改进了Apriori算法中支持度的计算与频繁集的确定过程 ,运用统计方法把挖掘结果形成可视的特征谱带 -化学基团规则式 ,通过具体的挖掘事例对挖掘结果进行分析与评价。挖掘出的规则式和波谱分析理论比较结果证明了挖掘结果的正确性 ,说明改进过的Apriori算法挖掘红外光谱数据库的有效性 相似文献
997.
Dragan Bošnački Edith Elkind Blaise Genest Doron Peled 《Annals of Mathematics and Artificial Intelligence》2009,56(2):187-210
The problem of state space search is fundamental to many areas of computer science, such as, e.g., AI and formal methods. Often, the state space to be searched
is huge, so optimizing the search is an important issue. In this paper, we consider the problem of visiting all states in
the setting where transitions between states are generated by actions, and the (reachable) states are not known in advance.
Some of the actions may commute, i.e., they result in the same state for every order in which they are taken. We show how
to use commutativity to achieve full coverage of the states, while traversing a relatively small number of edges. 相似文献
998.
Improved sensor network lifetime with multiple mobile sinks 总被引:4,自引:0,他引:4
A critical issue for data gathering in wireless sensor networks is the formation of energy holes near the sinks. Sensors near the sinks have to participate in relaying data on behalf of other sensors and thus will deplete their energy very quickly, resulting in network partitioning and limitation of the network lifetime. The solution that we propose in this paper is to use mobile sinks that change their location when the nearby sensors’ energy becomes low. In this way the sensors located near sinks change over time. In deciding a new location, a sink searches for zones with richer sensor energy.First, we study the improvement in network lifetime when sinks move on a predetermined path, along the perimeter of a hexagonal tiling. Two cases are considered for data gathering when sinks stop in the hexagon’s corners and when the sinks stop on multiple locations on the hexagon perimeter. This study shows an improvement of up to 4.86 times in network lifetime. Second, we design a distributed and localized algorithm used by the sinks to decide their next movement location such that the virtual backbone formed by the sinks remains interconnected at all times. Two extensions of the distributed algorithm, coverage requirement and limitation of the time-delivery requirement, are also addressed. Simulation results are presented to verify our approaches. 相似文献
999.
Summary The objective of the paper is to propose a simple method of formulation of 2D-theories for composite thin plates made of an arbitrary inhomogeneous linear-elastic material. The effect of inhomogeneity on the plate stiffness will be described by means of extra unknowns, called correctors, which have to satisfy a system of linear algebraic equations. The elimination of correctors can be performed in explicit form and leads to the formulas for effective stiffnesses of the plates under consideration. 相似文献
1000.