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51.
52.
Inclusion between XML types is important but expensive, and is much more expensive when unordered types are considered. We prove here that inclusion for XML types with interleaving and counting can be decided in polynomial time in the presence of two important restrictions: no element appears twice in the same content model, and Kleene star is only applied to disjunctions of single elements. 相似文献
53.
In the 21st century, all the major countries around the world are coming together to reduce the impact of energy generation and consumption on the global environment. Energy conservation and its efficient usage has become a top agenda on the desks of many governments. In the last decade, the drive to make homes automated and to deliver a better assisted living picked pace and the research into home automation systems accelerated, usually based on a centralized residential gateway. However most devised solutions fail to provide users with information about power consumption of different house appliances. The ability to collect power consumption information can lead us to have a more energy efficient society. The goal addressed in this paper is to enable residential gateways to provide the energy consumption information, in a machine understandable format, to support third party applications and services. To reach this goal, we propose a Semantic Energy Information Publishing Framework. The proposed framework publishes, for different appliances in the house, their power consumption information and other properties, in a machine understandable format. Appliance properties are exposed according to the existing semantic modeling supported by residential gateways, while instantaneous power consumption is modeled through a new modular Energy Profile ontology. 相似文献
54.
Anna Giovanna Sciancalepore Elisa Mele Valentina Arcadio Francesco Reddavide Francesco Grieco Giuseppe Spano Patrick Lucas Giovanni Mita Dario Pisignano 《Food microbiology》2013
The development of fast, reliable and culture-independent molecular tools to detect bacteria producing biogenic amines deserves the attention of research and ultimately of the food industry in order to protect consumers' health. Here we present the application of a simple, low-cost, fast and sensitive method to perform microdroplet-based multiplex PCR, directly on a food matrix, for the simultaneous detection of bacterial genes involved in biogenic amine biosynthesis. After inoculating wine with Lactobacillus brevis IOEB 9809, cell lysis and DNA amplification are performed in one single step, without preliminary nucleic acid extraction or purification treatments. The assay is performed in about 30 min, requiring 150 nL of starting sample and it enables the detection of down to 15 bacterial cells. With respect to traditional culture techniques, the speed, the simplicity and the cheapness of this procedure allow an effective monitoring of microbial cells during food-making and processing. 相似文献
55.
M. Cianchetti A. Arienti M. Follador B. Mazzolai P. Dario C. Laschi 《Materials science & engineering. C, Materials for biological applications》2011,31(6):1230-1239
The octopus is an invertebrate sea animal, considered as an interesting model of inspiration in robotics, due to its high dexterity, variable stiffness, and very complex behaviours, if compared with its position in the evolutionary scale. This paper reports the design of an artificial muscular hydrostat for developing an octopus-like robot. The experimental study consists of the fabrication of a set of mock-ups demonstrating some of the key features and patterns of movement of the octopus arm.The experimental trials performed with the different mock-ups demonstrated the suitability of the silicone materials used and the patterns of actuators activation to replicate the typical octopus movements of elongation, shortening, bending, and reaching. They also confirm that control is simplified by the arrangement of muscles as well as by the mechanical properties of the muscular hydrostat. 相似文献
56.
We consider a continuous time linear multi-inventory system with unknown demands bounded within ellipsoids and controls bounded within ellipsoids or polytopes. We address the problem of ε-stabilising the inventory since this implies some reduction of the inventory costs. The main results are certain conditions under which ε-stabilisability is possible through a saturated linear state feedback control. All the results are based on a linear matrix inequalities approach and on some recent techniques for the modelling and analysis of polytopic systems with saturations. Numerical simulations are provided. 相似文献
57.
In the last years Home Automation systems gained new momentum, permeating many human-related environments, from homes to hospitals. The rapid evolution of such systems showed several interoperability pitfalls and a generally insufficient support for advanced user–home interaction. To tackle these emerging issues, recent research works defined the concept of Intelligent Domotic Environments (IDEs) where different automation systems, appliances and devices are integrated into a single powerful environment, capable of providing Ambient Intelligence (AmI) functionalities. IDEs represent one of the first attempts to define a framework for AmI environments based on off-the-shelf domotic systems. This paper contributes to extend IDE capabilities by supporting basic intelligence requirements through a rule-based reasoning mechanism. Starting from a formal model of IDE elements (DogOnt), rules are defined to evaluate environment properties. Property checking is done both off-line, for structural properties, i.e., properties involving the physical structure and configuration of the IDE, and on-line for properties dependent on current IDE states. Two rule languages, SWRL and JenaRules, are considered for rule formalization and their reasoning performance is evaluated by comparing two different rule engines, namely Jess and Jena. Results show that rule-based reasoning can deal with quite complex property checking, effectively addressing basic intelligence for IDEs and providing the basis for more advanced behaviors such as user adaptation and proactive interaction. 相似文献
58.
3D graphene from CO2 and K as an excellent counter electrode for dye‐sensitized solar cells 下载免费PDF全文
3D graphene, which was synthesized directly from CO2 via its exothermic reaction with liquid K, exhibited excellent performance as a counter electrode for a dye‐sensitized solar cell (DSSC). The DSSC has achieved a high power conversion efficiency of 8.25%, which is 10 times larger than that (0.74%) of a DSSC with a counter electrode of the regular graphene synthesized via chemical exfoliation of graphite. The efficiency is even higher than that (7.73%) of a dye‐sensitized solar cell with an expensive standard Pt counter electrode. This work provides a novel approach to utilize a greenhouse gas for DSSCs. 相似文献
59.
Bradley T. Vander Zanden Richard Halterman Brad A. Myers Rob Miller Pedro Szekely Dario A. Giuse David Kosbie Rich McDaniel 《Software》2005,35(13):1275-1298
One‐way constraints have been incorporated in many graphical user interface toolkits because they are simple to learn, easy to write, and can express many types of useful graphical relationships. This paper is an evaluative paper that examines users' experience with one‐way constraints in two user interface development toolkits, Garnet and Amulet, over a 15‐year time span. The lessons gained from this examination can help guide the design of future constraint systems. The most important lessons are that (1) constraints should be allowed to contain arbitrary code that is written in the underlying toolkit language and does not require any annotations, such as parameter declarations, (2) constraints are difficult to debug and better debugging tools are needed, and (3) programmers will readily use one‐way constraints to specify the graphical layout of an application, but must be carefully and time‐consumingly trained to use them for other purposes. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
60.
Jean-Christophe Zufferey Alexis Guanella Antoine Beyeler Dario Floreano 《Autonomous Robots》2006,21(3):243-254
Because of their ability to naturally float in the air, indoor airships (often called blimps) constitute an appealing platform
for research in aerial robotics. However, when confronted to long lasting experiments such as those involving learning or
evolutionary techniques, blimps present the disadvantage that they cannot be linked to external power sources and tend to
have little mechanical resistance due to their low weight budget. One solution to this problem is to use a realistic flight
simulator, which can also significantly reduce experimental duration by running faster than real time. This requires an efficient
physical dynamic modelling and parameter identification procedure, which are complicated to develop and usually rely on costly
facilities such as wind tunnels. In this paper, we present a simple and efficient physics-based dynamic modelling of indoor
airships including a pragmatic methodology for parameter identification without the need for complex or costly test facilities.
Our approach is tested with an existing blimp in a vision-based navigation task. Neuronal controllers are evolved in simulation
to map visual input into motor commands in order to steer the flying robot forward as fast as possible while avoiding collisions.
After evolution, the best individuals are successfully transferred to the physical blimp, which experimentally demonstrates
the efficiency of the proposed approach.
Jean-Christophe Zufferey and Alexis Guanella contributed equally to this work. 相似文献