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131.
Air management for diesel engines is a major challenge from the control point of view because of the highly nonlinear behavior of this system. For this reason, linear control techniques are unable to provide the required performance, and nonlinear controllers are used instead. This article discusses two fundamental steps when designing a control system. Firstly, a methodology to identify Takagi–Sugeno (T–S) structures using experimental data is proposed. Secondly, the design of a fuzzy controller in PDC structure (Parallel Distributed Compensation) is presented. The parameters of this controller are obtained from a LMI (Linear Matrix Inequalities) minimization problem. 相似文献
132.
J. Cucurull R. Martí G. Navarro-Arribas S. Robles B. Overeinder J. Borrell 《Computer Communications》2009,32(4):712-729
Mobile agents are autonomous software entities driven by a set of goals and tasks. Reactivity, social ability, autonomy, the ability to move to different network locations, and the weak agent notion of proactiveness, allow for autonomous processing of distributed information according to their environment (context awareness).Although agent mobility has been devised for homogeneous environments, deployment of agent mobility in heterogeneous environments has been hindered by the absence of a common set of interoperation rules and ontologies for different agent middlewares.In this article, an agent migration model based on the communication standards of the IEEE-FIPA organisation is proposed. The approach described encompasses the definition of several specifications to achieve interoperability in the migration process in heterogeneous environments.The model provides a basic and extensible common migration process, which is flexible enough to support different kinds of migration methods and future upgrades. It is completely independent of any specific middleware implementation. 相似文献
133.
134.
In an adaptive and intelligent educational system (AIES), the process of learning pedagogical policies according the students needs fits as a Reinforcement Learning (RL) problem. Previous works have demonstrated that a great amount of experience is needed in order for the system to learn to teach properly, so applying RL to the AIES from scratch is unfeasible. Other works have previously demonstrated in a theoretical way that seeding the AIES with an initial value function learned with simulated students reduce the experience required to learn an accurate pedagogical policy. In this paper we present empirical results demonstrating that a value function learned with simulated students can provide the AIES with a very accurate initial pedagogical policy. The evaluation is based on the interaction of more than 70 Computer Science undergraduate students, and demonstrates that an efficient and useful guide through the contents of the educational system is obtained. 相似文献
135.
136.
Carlos?Alberto?Martínez-Angeles Haicheng?Wu Inês?DutraEmail author Vítor?Santos?Costa Jorge?Buenabad-Chávez 《International journal of parallel programming》2016,44(3):663-685
Relational learning algorithms mine complex databases for interesting patterns. Usually, the search space of patterns grows very quickly with the increase in data size, making it impractical to solve important problems. In this work we present the design of a relational learning system, that takes advantage of graphics processing units (GPUs) to perform the most time consuming function of the learner, rule coverage. To evaluate performance, we use four applications: a widely used relational learning benchmark for predicting carcinogenesis in rodents, an application in chemo-informatics, an application in opinion mining, and an application in mining health record data. We compare results using a single and multiple CPUs in a multicore host and using the GPU version. Results show that the GPU version of the learner is up to eight times faster than the best CPU version. 相似文献
137.
The intrinsic laminarity of microfluidic devices impedes the mixing of multiple fluids over short temporal or spatial scales. Despite the existence of several mixers capable of stirring and stretching the flows to promote mixing, most approaches sacrifice temporal or spatial control, portability, or flexibility in terms of operating flow rates. Here, we report a novel method for rapid micromixing based on the generation of cavitation bubbles. By using a portable battery-powered electric circuit, we induce a localized electric spark between two tip electrodes perpendicular to the flow channel that results in several cavitation events. As a result, a vigorous stirring mechanism is induced. We investigate the spatiotemporal dynamics of the spark-generated cavitation bubbles and quantify the created flow disturbance. We demonstrate rapid (in the millisecond timescale) and efficient micromixing (up to 98%) within a length scale of only 200 µm and over a flow rate ranging from 5 to 40 µL/min. 相似文献
138.
Eric Pedrol Javier Martínez Magdalena Aguiló Manuel Garcia-Algar Moritz Nazarenus Luca Guerrini Eduardo Garcia-Rico Francesc Díaz Jaume Massons 《Microfluidics and nanofluidics》2017,21(12):181
This paper presents an optofluidic device for cell discrimination with two independent interrogation regions. Pumping light is coupled to the device, and cell fluorescence is extracted from the two interrogation zones by using optical fibers embedded in the optofluidic chip. To test the reliability of this device, AU-565 cells—expressing EpCAM and HER2 receptors—and RAMOS cells were mixed in a controlled manner, confined inside a hydrodynamic focused flow in the microfluidic chip and detected individually so that they could be discriminated as positive (signal reception from fluorescently labeled antibodies from the AU-565 cells) or negative events (RAMOS cells). A correlation analysis of the two signals reduces the influence of noise on the overall data. 相似文献
139.
Juan M. Marín Pérez Jorge Bernal Bernabé Jose M. Alcaraz Calero Felix J. Garcia Clemente Gregorio Martínez Pérez Antonio F. Gómez Skarmeta 《Future Generation Computer Systems》2011,27(1):40-55
There are a few issues that still need to be covered regarding security in the Grid area. One of them is authorization where there exist good solutions to define, manage and enforce authorization policies in Grid scenarios. However, these solutions usually do not provide Grid administrators with semantic-aware components closer to the particular Grid domain and easing different administration tasks such as conflict detection or resolution. This paper defines a proposal based on Semantic Web to define, manage and enforce security policies in a Grid scenario. These policies are defined by means of semantic-aware rules which help the administrator to create higher-level definitions with more expressiveness. These rules also permit performing added-value tasks such as conflict detection and resolution, which can be of interest in medium and large scale scenarios where different administrators define the authorization rules that should be followed before accessing a resource in the Grid. The proposed solution has been also tested providing some reasonable response times in the authorization decision process. 相似文献
140.
Francisco Jes��s Mart��n-Mateos Jos�� Luis Ruiz-Reina Jos�� Antonio Alonso Mar��a Jos�� Hidalgo 《Journal of Automated Reasoning》2011,47(3):229-250
Higman??s lemma is an important result in infinitary combinatorics, which has been formalized in several theorem provers. In this paper we present a formalization and proof of Higman??s Lemma in the ACL2 theorem prover. Our formalization is based on a proof by Murthy and Russell, where the key termination argument is justified by the multiset relation induced by a well-founded relation. To our knowledge, this is the first mechanization of this proof. 相似文献