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排序方式: 共有246条查询结果,搜索用时 31 毫秒
101.
Pattern Analysis and Applications - The world's population is aging, and eldercare services that use smart facilities such as smart homes are widely common in societies now. With the aid of...  相似文献   
102.
This paper presents a robust mapping algorithm for an application in autonomous robots. The method is inspired by the notion of entropy from information theory. A kernel density estimator is adopted to estimate the appearance probability of samples directly from the data. An Entropy Based Robust (EBR) estimator is then designed that selects the most reliable inliers of the line segments. The inliers maintained by the entropy filter are those samples that carry more information. Hence, the parameters extracted from EBR estimator are accurate and robust to the outliers. The performance of the EBR estimator is illustrated by comparing the results with the performance of three other estimators via simulated and real data.  相似文献   
103.
104.
A JURASSIC DELTA IN THE EASTERN ALBORZ, NE IRAN   总被引:1,自引:0,他引:1  
A clastic dominated Lower-Middle Jurassic sequence, known as the Shemshak Formation, is extensively exposed in the Eastern Alborz area, NE Iran. The unit represents a deltaic complex sandwiched between carbonate rocks. Sedimentological study of the formation outcrops has revealed that it was deposited in environments ranging from subaerial to subaqueous delta plains.
Potential source, reservoir and cap rocks are present within the Shemshak Formation; under favourable conditions, generation and accumulation of hydrocarbons in significant quantities can be envisaged. It is suggested that the Shemshak delta, buried under the thick Neogene sediments in the Eastern Alborz area, is a highly prospective exploration target with potential for a multipay section.  相似文献   
105.
In this research, we aimed at improving the setting properties and biocompatibility of the mineral trioxide aggregate‐like cements while maintaining the main chemical formula. Consequently, chitosan and zirconium oxide were added to the cement instead of bismuth oxide to improve the mechanical behavior, limit the possible toxicity, and enhance the bioactivity of the cements. Adding zirconia resulted in a shorter setting time and adding chitosan contributed to the setting time, mechanical strength, and biocompatibility at the same time. Thus, cements containing both chitosan and zirconia had the shortest setting time, highest compressive strength, and apatite‐forming ability.  相似文献   
106.
In the "Heidelberg Long Term Psychotherapy Follow-up Project", a naturalistic study design, all types of treatment were included that had been performed at the Psychosomatic Clinic of the University of Heidelberg for a certain period (combined inpatient and outpatient individual and group therapy, as well as outpatient dynamic psychotherapies and psychoanalyses). The specific value of this project is due to the fact that--apart from many other, for instance psychological, assessment evaluations--three to five individual therapy goals had been predetermined for each patient before starting the treatment (goal attainment scaling). After the end of therapy and at the time of follow-up (3.5 years later on the average), attainment of these goals was assessed by an independent rater. A total of 208 patients were examined who were evaluated according to their diagnosis (neurotic, functional or psychosomatic disorders) and the kind of treatment. With regard to symptomatology, individual therapy goals, psychological assessment and patient satisfaction, the overall results were good, partly very good, and were almost invariably stable during the long follow-up period. Two particular results are discussed separately: 1. As far as symptomatology was concerned, the group of psychoanalysis patients could not maintain the good outcome at the end of therapy during the long follow-up period. 2. Patients with "psychosomatic disorders" attained remarkably good results, particularly if the treatment had initially been an inpatient setting.  相似文献   
107.
This work presents an adaptive fuzzy sliding mode controller (AFSMC) that combines a robust proportional integral control law for use in designing single-input single-output (SISO) nonlinear systems with uncertainties and external disturbances. The fuzzy logic system is used to approximate the unknown system function and the AFSMC algorithm is designed by used of sliding mode control techniques. Based on the Lyapunov theory, the proportional integral control law is designed to eliminate the chattering action of the control signal. The simplicity of the proposed scheme facilitates its implementation and the overall control scheme guarantees the global asymptotic stability in the Lyapunov sense if all the signals involved are uniformly bounded. Simulation studies have shown that the proposed controller shows superior tracking performance.  相似文献   
108.
In this study, an innovative in situ green strategy was applied to prepare bacterial cellulose/silver nanocomposites using green tea as a substrate for the fermentation of Acetobacter xylinum bacteria and a reducing agent for the in situ synthesis of silver nanoparticles. The samples were analyzed by different characterization tests including field emission scanning electron microscopy (FESEM), X-ray diffraction analysis (XRD), UV–vis spectroscopy, atomic absorption spectroscopy, and ATR. The results indicated the excellent antibacterial activities with 100% bacterial reduction percentage and inhibition zones of 2.6 and 2.8 cm against S. aureus and E. coli, respectively. Moreover, water absorption percentage and vertical wicking measurements supported the hydrogel properties of the prepared bio-cellulose/silver nanocomposites. Finding of this research suggested the potential of the proposed green route for preparing antibacterial BC which can be regarded as a candidate for future wound healing applications.  相似文献   
109.
Ho HF  Rad AB  Wong YK  Lo WL 《ISA transactions》2003,42(4):577-593
This paper presents a novel method to determine the parameters of a first-order plus dead-time model using neural networks. The outputs of the neural networks are the gain, dominant time constant, and apparent time delay. By combining this algorithm with a conventional PI or PID controller, we also present an adaptive controller which requires very little a priori knowledge about the plant under control. The simplicity of the scheme for real-time control provides a new approach for implementing neural network applications for a variety of on-line industrial control problems. Simulation and experimental results demonstrate the feasibility and adaptive property of the proposed scheme.  相似文献   
110.
We present a novel fused feed-forward neural network controller inspired by the notion of task decomposition principle. The controller is structurally simple and can be applied to a class of control systems that their control requires manipulation of two input variables. The benchmark problem of inverted pendulum is such example that its control requires availability of the angle as well as the displacement. We demonstrate that the lateral control of autonomous vehicles belongs to this class of systems and successfully apply the proposed controller to this problem. The parameters of the controller are encoded into real value chromosomes for genetic algorithm (GA) optimization. The neural network controller contains three neurons and six connection weights implying a small search space implying faster optimization time due to few controller parameters. The controller is also tested on two benchmark control problems of inverted pendulum and the ball-and-beam system. In particular, we apply the controller to lateral control of a prototype semi-autonomous vehicle. Simulation results suggest a good performance for all the tested systems. To demonstrate the robustness of the controller, we conduct Monte-Carlo evaluations when the system is subjected to random parameter uncertainty. Finally experimental studies on the lateral control of a prototype autonomous vehicle with different speed of operation are included. The simulation and experimental studies suggest the feasibility of this controller for numerous applications.  相似文献   
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