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71.
This correspondence presents a relaxation of some earlier linear matrix inequality (LMI) conditions, which allow setting up less conservative stability or performance conditions for Takagi-Sugeno fuzzy models. Unlike the previous literature, this correspondence takes into account the knowledge of the membership functions' shape by considering bounds on them and their cross products (interpreted as an overlap measure), introducing auxiliary LMI variables. Numerical examples illustrate the achieved improvements.  相似文献   
72.
The simultaneous synthesis and densification of dense TiC–TiB2 composite has been investigated starting from Ti, B4C, and C as reactants, and using the spark plasma sintering (SPS) technique. The optimal conditions for complete conversion of the reactants to the composite were determined for different applied DC current levels. A kinetic investigation performed allows us to conclude that solid-state diffusion is the mechanism governing the synthesis process. It is seen that TiC is the first phase formed, while TiB2 formation occurs afterward. Two intermediate boride phases, i.e. TiB and Ti3B4, are also formed but, as the SPS holding time was augmented, they were gradually and completely converted to TiB2. Moreover, it is found that in order to reach relatively high dense products, an electric current needs to be applied for time intervals longer than those required for obtaining complete conversion. A pure dense product (relative density ∼98%) was obtained when an electric pulsed current of 1100 A and a mechanical pressure of 20 MPa were applied for about 4 min.  相似文献   
73.
Subalpine fir (Abies lasiocarpa Hook) lumber containing wetpockets (wetwood) was used for the measurements of gas permeability and the results were then compared to the gas permeability of normal wood, which was free of the wetpockets. The impacts of pretreatment methods were also investigated, including steaming at green condition, steaming at fiber saturation point (FSP), microwave treatment, and radio-frequency treatment. Results from this study demonstrated that both the transverse and the longitudinal gas permeability of subalpine fir wetwood are greater than that of normal wood. There is no significant change in the permeability after 4-h steaming pretreatment at green condition and at FSP. The impacts of microwave and radio-frequency pretreatments were not significant, but the findings cannot be generalized because they may depend on the power intensity applied.  相似文献   
74.
Hormone-refractory prostate cancer (HRPC) patients often have nonmeasurable disease. In such patients, predictive biomarkers other than tumor response may be required to compare therapeutic effects. We examined the predictive value for survival of various clinical and laboratory parameters, including prostate-specific antigen (PSA), in HRPC patients treated with suramin. Data from 103 HRPC patients were analyzed using various survival analyses, the likelihood ratio approach, and logistic regression analyses. When pretreatment factors, percentage decrease in PSA at 4 weeks from start of treatment (deltaPSA), and updated survival data were fit by a multivariate Cox proportional hazards model, acid phosphatase, lactate dehydrogenase, and deltaPSA were significant, with risk ratios close to 1. There was a decrease in likelihood ratio with increasing APSA. A logistic regression model was developed to predict the probability of <1 year of survival from the start of treatment. Hemoglobin and deltaPSA were found to be significant variables. However, in view of the complexities involving the relationship between PSA expression and prostate cancer growth and possible selective effect of treatment on PSA, further prospective testing is necessary. Therefore, deltaPSA cannot necessarily be used as a biomarker for survival response in individual patients during the evaluation of the therapeutic response of HRPC to new antineoplastic drugs.  相似文献   
75.

Studying the changes of shape is a common concern in many scientific fields. We address here two problems: (1) quantifying the deformation between two given shapes and (2) transporting this deformation to morph a third shape. These operations can be done with or without point correspondence, depending on the availability of a surface matching algorithm, and on the type of mathematical procedure adopted. In computer vision, the re-targeting of emotions mapped on faces is a common application. We contrast here four different methods used for transporting the deformation toward a target once it was estimated upon the matching of two shapes. These methods come from very different fields such as computational anatomy, computer vision and biology. We used the large diffeomorphic deformation metric mapping and thin plate spline, in order to estimate deformations in a deformational trajectory of a human face experiencing different emotions. Then we use naive transport (NT), linear shift (LS), direct transport (DT) and fanning scheme (FS) to transport the estimated deformations toward four alien faces constituted by 240 homologous points and identifying a triangulation structure of 416 triangles. We used both local and global criteria for evaluating the performance of the 4 methods, e.g., the maintenance of the original deformation. We found DT, LS and FS very effective in recovering the original deformation while NT fails under several aspects in transporting the shape change. As the best method may differ depending on the application, we recommend carefully testing different methods in order to choose the best one for any specific application.

  相似文献   
76.

Contracts play an important role in business management where relationships among different parties are dictated by legal rules. Electronic contracts have emerged mostly due to technological advances and electronic trading between companies and customers. New challenges have then arisen to guarantee reliability among the stakeholders in electronic negotiations. In this scenario, automatic verification of electronic contracts appeared as an imperative support, specially the conflict detection task of multi-party contracts. The problem of checking contracts has been largely addressed in the literature, but there are few, if any, methods and practical tools that can deal with multi-party contracts using a contract language with deontic and dynamic aspects as well as relativizations, over the same formalism. In this work we present an automatic checker for finding conflicts on multi-party contracts modeled by an extended contract language with deontic operators and relativizations. Moreover a well-known case study of sales contract is modeled and automatically verified by our tool. Further, we performed practical experiments in order to evaluate the efficiency of our method and the practical tool.

  相似文献   
77.
Distributed and Parallel Databases - Given two datasets of points (called Query and Training), the Group (K) Nearest-Neighbor (GKNN) query retrieves (K) points of the Training with the smallest sum...  相似文献   
78.
Neural Computing and Applications - In this paper, we present the novel Deep-MEG approach in which image-based representations of magnetoencephalography (MEG) data are combined with ensemble...  相似文献   
79.
A fuzzy queue-aware routing approach for wireless mesh networks   总被引:1,自引:0,他引:1  
Recent advances in Wireless Mesh Networks (WMNs) have overcome the drawbacks of traditional wired and ad-hoc networks and now they are seen as a means of allowing last mile communications with quality level assurance in Future Multimedia Systems. However, new routing schemes are needed to provide end-to-end Quality of Service (QoS) and Quality of Experience (QoE) support for delay/loss/jitter-sensitive multimedia applications. The well-known OLSR (Optimized Link State Routing) protocol with ETX (Expected Transmission Count) metric brings many benefits to the path selection process, but has a drawback with regard to queue availability management, which reduces the system performance. This problem is caused when OLSR-EXT control messages are exchanged and the queues of mesh routers along the end-to-end communication path are overloaded. As a result, multimedia-related packets will suffer from loss/delay/jitter and the overall system performance will decrease. This paper proposes the Optimized Link State Routing-Fuzzy ETX Queue (OLSR-FEQ) protocol to overcome the limitations of OLSR-ETX regarding queue availability, QoS and QoE assurance. OLSR-FEQ optimizes network and user-based parameters by coordinating queue availability, QoS and fuzzy issues in the routing decision process as a way of allocating the best paths for multimedia applications. Performance evaluations were carried out with the Network Simulator (NS-2.34) to show the benefits of the proposed solution when compared with existing routing schemes, namely OLSR-ETX, OLSR-FLC, OLSR-MD and HWMP (IEEE 802.11s standard), regarding QoS (unsuccessful packet delivery and throughput) and QoE (PSNR, SSIM, VQM and MOS) parameters.  相似文献   
80.
The recent popularity of digital cameras has posed a new problem: how to efficiently store and retrieve the very large number of digital photos captured and chaotically stored in multiple locations without any annotation. This paper proposes an infrastructure, called PhotoGeo, which aims at helping users with the people photo annotation, event photo annotation, storage and retrieval of personal digital photos. To achieve the desired objective, PhotoGeo uses new algorithms that make it possible to annotate photos with the key metadata to facilitate their retrieval, such as: the people who were shown in the photo (who); where it was captured (where); the date and time of capture (when); and the event that was captured. The paper concludes with a detailed evaluation of these algorithms.  相似文献   
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