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21.
This article presents a general approach for employing lesion analysis to address the fundamental challenge of localizing functions in a neural system. We describe functional contribution analysis (FCA), which assigns contribution values to the elements of the network such that the ability to predict the network's performance in response to multilesions is maximized. The approach is thoroughly examined on neurocontroller networks of evolved autonomous agents. The FCA portrays a stable set of neuronal contributions and accurate multilesion predictions that are significantly better than those obtained based on the classical single lesion approach. It is also used for a detailed synaptic analysis of the neurocontroller connectivity network, delineating its main functional backbone. The FCA provides a quantitative way of measuring how the network functions are localized and distributed among its elements. Our results question the adequacy of the classical single lesion analysis traditionally used in neuroscience and show that using lesioning experiments to decipher even simple neuronal systems requires a more rigorous multilesion analysis.  相似文献   
22.
In the process of analyzing knowledge innovation, it is necessary to identify the existing boundaries of knowledge so as to determine whether knowledge is new – outside these boundaries. For a patent to be granted, all aspects of the patent request must be studied to determine the patent innovation. Knowledge innovation for patent requests depends on analyzing current state of the art in multiple languages. Currently the process is usually limited to the languages and search terms the patent seeker knows. The paper describes a model for representing the patent request by a set of concepts related to a multilingual knowledge ontology. The search for patent knowledge is based on Fuzzy Logic Decision Support and allows a multilingual search. The model was analyzed using a twofold approach: a total of 104,296 patents from the United States Patent and Trademark Office were used to analyze the patent extraction process, and patents from the Korean, US, and Chinese patent offices were used in the analysis of the multilingual decision process. The results display high recall and precision and suggest that increasing the number of languages used only has minor effects on the model results.  相似文献   
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FNS Control Schemes for the Upper Limb   总被引:1,自引:0,他引:1  
This paper is concerned with the problems of control associated with the application of functional neuromuscular stimulation of the upper limb, concentrating on elbow flexion/extension and wrist pronation/supination. A closed-loop controller is needed in order to overcome the gain nonlinearities and plant dynamic parameter variations. Controllers were developed based on models and parameters previously established. Two controllers are discussed in detail, a thirdorder feedforward controller and a model reference adaptive controller. There were no striking differences in the performances of the thirdorder controllers. The conventional controllers, however, required a lengthy a priori identification procedure each time they were used. This was performed implicitly by the adaptive controller within a few seconds, making it a practical proposition for an FNS controller.  相似文献   
25.
An annular laser beam based powder cladding head, which enables an axial powder feeding and variation of the laser beam intensity distribution (LBID) on the workpiece surface is presented. The influence of typical LBIDs, including Ring, Tophat(?), Tophat(+), and Gaussian-like, on a cladding process has been characterized based on the process and melt pool visualization, powder catchment efficiency, clad layer geometry, and porosity. The results showed that the most stable process without plasma formation but with low dilution and porosity of the clad layer can be achieved within the range from a Ring to a Tophat(?) LBID. Additionally, axial powder feeding results in a high powder catchment efficiency above 80%.  相似文献   
26.
This article focuses on the quasistatic axial compression behavior and the consequent energy absorption of three different types of carbon/epoxy braided composite tubes. The focus is to evaluate the effect of sample length and braiding angle on the energy absorption and failure mechanism of the braided composite tubes. All tubes were manufactured with carbon fiber through four‐step 1 × 1 braiding process and epoxy resin. Quasistatic axial compression tests were carried out to comprehend the failure mechanism and the corresponding compressive load–displacement characteristics of each braided composite tube. The quasistatic compression test parameters such as the compression peak load and the energy absorption of all these composite tubes were compared. It was found that as the length of the sample increased, the peak load reduced and the energy absorption of the braided tubes at 45° braiding angle was considerably higher than that of other braiding angles of 25° and 35°. The failure modes included matrix crack along the braiding angle, fiber breakage, bulging and debonding between yarns. POLYM. COMPOS., 37:3210–3218, 2016. © 2015 Society of Plastics Engineers  相似文献   
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We study bottleneck labeled optimization problems arising in the context of graph theory. This long-established model partitions the set of edges into classes, each of which is identified by a unique color. The generic objective is to construct a subgraph of prescribed structure (such as an s-t path, a spanning tree, or a perfect matching) while trying to minimize the maximum (or, alternatively, maximize the minimum) number of edges picked from any given color.  相似文献   
29.
Studies have shown a connection between the individual personality of the user and the way he or she behaves on line. Today many millions of people around the world are connected by being members of various Internet social networks. Ross et al. (2009) studied the connection between the personality of the individual users and their behavior on a social network. They based their study on the self-reports of users of Facebook, one of the most popular social networks, and measured five personality factors using the NEO-PI-R (Costa & McCrae, 1992) questionnaire. They found that while there was a connection between the personalities of surfers and their behavior on Facebook, it was not strong. This study is based on that of Ross et al. (2009), but in our study the self-reports of subjects, were replaced by more objective criteria, measurements of the user-information upload on Facebook. A strong connection was found between personality and Facebook behavior. Implications of the results are discussed.  相似文献   
30.
This article presents an overview of the commercialisation experiences of photovoltaics and draws some conclusion from the past and applies them to the future. In particular, the development for this industry in Africa is examined to identify the areas of strength and potential as well as the necessary infrastructure—for production, distribution and installation in order to support its growth. The question of capital requirement versus the efficiency of photovoltaics is highlighted and the reliabilty factor is analysed. As a result of examining the past, three issues seem crucial for the future development of photovoltaics, especially in Africa: (1) technology development; (2) education; (3) finance. These issues are addressed and their interdependence and impact on the use of photovoltaics are explored. The success stories of several photovoltaic companies in Africa, in spite of their problems, can be a source of optimism for the future contribution of this industry to the improved quality of life and economic growth as well as the employment opportunities on this continent. Finally, a method of co-operation between research in photovoltaics at the universities and local industry is proposed as part of the Research and Development (R&D) infrastructure necessary for the technical support of this field.  相似文献   
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