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排序方式: 共有485条查询结果,搜索用时 15 毫秒
1.
This paper proposes a system based on a parallel genetic algorithm with enhanced encoding and operational abilities. The system, used to evolve feedforward artificial neural networks, has been applied to two widely different problem areas: Boolean function learning and robot control. It is shown that the good results obtained in both cases are due to two factors: first, the enhanced exploration abilities provided by the search-space reducing evolution of both coding granularity and network topology, and, second, the enhanced exploitational abilities due to a recently proposed cooperative local optimizing genetic operator. 相似文献
2.
Abstract: This paper describes a system of shallow and deep knowledge acquisition and representation for diagnostic expert systems. The acquisition system is integrated into a diagnostic expert system shell. Shallow knowledge is represented in a failure model as a set of cause-effect relations among the possible faults, while deep knowledge is represented in three deep models: a functional, a deep causal and a taxonomic model. The acquisition and the representation of all the models are fully integrated. The deep knowledge is used by the final expert system in order to provide the user with deep explanations of the cause-effect relations of the failure model. 相似文献
3.
Vittorio Ghergia 《Sadhana》1992,17(3-4):411-430
Starting from the present state-of-the-art of discrete devices up to the realization of monolithic semiconductor integrated
prototypes, an overview of optoelectronic devices for telecommunications is given. Among discrete devices single frequency
lasers, tunable and multi-sectionDFB lasers andPIN andAPD photodiode detectors are analysed, including the use of new technologies in progress for a second generation of devices.
On the future perspective ofIBCN distribution networks, some economics of the hybrid and monolithic form of integration are attempted. Finally a short outline
of the most recent achievements in monolithic integration is presented, taking into particular consideration the activities
in this field byEEC ESPRIT andRACE programmes. 相似文献
4.
Vincenzo Augugliaro Vittorio Loddo Ignacio Maldonado Raffaele Molinari 《Solar Energy》2005,79(4):402-408
The photocatalytic oxidation of a common antibiotic, the lincomycin was carried out in aqueous suspensions of polycrystalline TiO2 Degussa P25 irradiated by sunlight. In order to improve the performance of the lincomycin degradation a hybrid system consisting of a solar photoreactor with the photocatalyst in suspension coupled with a membrane module, used to confine both photocatalyst and pollutants in the reaction environment, was tested.A preliminary study was carried out in order to determine some kinetics parameters of the drug photodegradation. The influence of initial substrate concentration on the lincomycin photooxidation rate was investigated. The photooxidation rate follows a pseudo-first order kinetics with respect to the lincomycin concentration under the used experimental conditions. The presence of the membrane reactor allows the catalyst separation and to operate in continuous mode as the membranes rejection for lincomycin and its oxidation products was quite high. 相似文献
5.
Margaret Ottaviano Emilio Francesco Giunta Marianna Tortora Marcello Curvietto Laura Attademo Davide Bosso Cinzia Cardalesi Mario Rosanova Pietro De Placido Erica Pietroluongo Vittorio Riccio Brigitta Mucci Sara Parola Maria Grazia Vitale Giovannella Palmieri Bruno Daniele Ester Simeone 《International journal of molecular sciences》2021,22(7)
As widely acknowledged, 40–50% of all melanoma patients harbour an activating BRAF mutation (mostly BRAF V600E). The identification of the RAS–RAF–MEK–ERK (MAP kinase) signalling pathway and its targeting has represented a valuable milestone for the advanced and, more recently, for the completely resected stage III and IV melanoma therapy management. However, despite progress in BRAF-mutant melanoma treatment, the two different approaches approved so far for metastatic disease, immunotherapy and BRAF+MEK inhibitors, allow a 5-year survival of no more than 60%, and most patients relapse during treatment due to acquired mechanisms of resistance. Deep insight into BRAF gene biology is fundamental to describe the acquired resistance mechanisms (primary and secondary) and to understand the molecular pathways that are now being investigated in preclinical and clinical studies with the aim of improving outcomes in BRAF-mutant patients. 相似文献
6.
Riccardo Carli Raymond Le Van Mao Claudia L. Blanchi Vittorio Ragaini 《Catalysis Letters》1993,21(3-4):265-274
Gallium species which were incorporated initially in the oxide form, were all in the (+3) oxidation state in the hybrid catalyst and exhibited two types of hydrogen chemisorption sites, shw and shs. The stronger sorption sites shs which predominated at higher gallium dispersion, corresponded probably to the most effective surface configuration for gallium in the aromatization ofn-butane. 相似文献
7.
The conditions for obtaining recrystallization in more ordered modifications are described for an uniaxially oriented sample of isotactic polypropylene, annealed with fixed ends. These recrystallization conditions are related to the conditions of a lamination process. 相似文献
8.
Protecting privacy on the Web is becoming increasingly complicated because of the considerable amount of personal and sensitive information left by users in many locations during their Web browsing and the silent actions of third party sites that collect data, aggregate information and build personal profiles of Internet users in order to provide free and personalized services. On the other hand, most of people are unaware that their information may be collected online, and that, after their aggregation from multiple sources, could be used for secondary purposes, such as linked to allow identification, without user’s notice. 相似文献
9.
Daniel Dominguez Gouvêa Cyro de A. Assis D. Muniz Gilson A. Pinto Alberto Avritzer Rosa Maria Meri Leão Edmundo de Souza e Silva Morganna Carmem Diniz Vittorio Cortellessa Luca Berardinelli Julius C. B. Leite Daniel Mossé Yuanfang Cai Michael Dalton Lucia Happe Anne Koziolek 《Software and Systems Modeling》2013,12(4):765-787
In this paper, we report on our experience with the application of validated models to assess performance, reliability, and adaptability of a complex mission critical system that is being developed to dynamically monitor and control the position of an oil-drilling platform. We present real-time modeling results that show that all tasks are schedulable. We performed stochastic analysis of the distribution of task execution time as a function of the number of system interfaces. We report on the variability of task execution times for the expected system configurations. In addition, we have executed a system library for an important task inside the performance model simulator. We report on the measured algorithm convergence as a function of the number of vessel thrusters. We have also studied the system architecture adaptability by comparing the documented system architecture and the implemented source code. We report on the adaptability findings and the recommendations we were able to provide to the system’s architect. Finally, we have developed models of hardware and software reliability. We report on hardware and software reliability results based on the evaluation of the system architecture. 相似文献
10.
Building a software architecture that meets functional requirements is a quite consolidated activity, whereas keeping high quality attributes is still an open challenge. In this paper we introduce an optimization framework that supports the decision whether to buy software components or to build them in-house upon designing a software architecture. We devise a non-linear cost/quality optimization model based on decision variables indicating the set of architectural components to buy and to build in order to minimize the software cost while keeping satisfactory values of quality attributes. From this point of view, our tool can be ideally embedded into a Cost Benefit Analysis Method to provide decision support to software architects. The novelty of our approach consists in building costs and quality attributes on a common set of decision variables related to software development. We start from a special case of the framework where the quality constraints are related to the delivery time and the product reliability, and the model solution also devises the amount of unit testing to be performed on built components. We generalize the framework formulation to represent a broader class of architectural cost-minimization problems under quality constraints, and discuss advantages and limitations of such approach. 相似文献