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1.
There has been a rapid increase in the resolution of small‐sized and medium‐sized displays. This study determines an upper discernible limit for display resolution. A range of resolutions varying from 254–1016 PPI were evaluated using simulated display by 49 subjects at 300 mm viewing distance. The results of the study conclusively show that users can discriminate between 339 and 508 PPI and in many cases between 508 and 1016 PPI.  相似文献   
2.
We present a cross-layer optimized video rate adaptation and user scheduling scheme for multi-user wireless video streaming aiming for maximum quality of service (QoS) for each user,, maximum system video throughput, and QoS fairness among users. These objectives are jointly optimized using a multi-objective optimization (MOO) framework that aims to serve the user with the least remaining playback time, highest delivered video seconds per transmission slot and maximum video quality. Experiments with the IS-856 (1timesEV-DO) standard numerology and ITU pedestrian A and vehicular B environments show significant improvements over the state-of- the-art wireless schedulers in terms of user QoS, QoS fairness, and the system throughput.  相似文献   
3.
Sunay  M. Selin  U&#;ur  &#;aziye  Pekcan  &#;nder 《Polymer Bulletin》2020,77(6):3061-3077
Polymer Bulletin - Steady-state fluorescence and UV–Vis techniques were used to study the film formation behavior of composites consisting of pyrene (P)-labeled polystyrene (PS) latex and...  相似文献   
4.
This paper proposes a method for reducing vibrations in flexible systems by using the input shaping. A new input shaper technique based on Pulse Width Modulation (PWM) is used to shape the input.Since unity magnitude (UM) input shaping is easy to implement and provides less control duration, it has been preferred for many application areas. An analytical solution to time locations of the UM shaper requires very complex mathematical expressions due to involving in dependent constraint equations. This paper presents a simple PWM based input shaping method. The proposed technique allows designing UM shapers without analytical solution especially for the shapers having higher order impulse sequence. The method requires only the estimated value of system natural frequency and damping ratio. Desired numbers of impulses can be obtained by comparing reference signal amplitude and carrier wave frequency of a PWM. Analysis and experimental results demonstrate the effectiveness of the proposed method.  相似文献   
5.
In a wireless multihop broadcasting scenario, a number of relay nodes may cooperate the source node in order to improve the capacity of the network. However, the imposition of total energy and maximum hop constraints to this system in a practical setting. In this paper, we study an ad-hoc network with infinitely many nodes and analytically find the number and positions of rebroadcasting relay nodes to achieve the optimal broadcast capacity. The interference due to multiple transmissions in the same geographical area is taken into account. According to the results of this theoretical model, we propose two heuristics, one distributed and one centralized, as suboptimal but practical solutions to the relay selection problem in wireless multihop broadcasting. We discuss the broadcast capacity performances and CSI (channel state information) requirements of these algorithms. The results illustrate that the benefits of peer-assisted broadcasting are more pronounced in the centralized relay selection algorithm when compared to the fully randomized and distributed selection under a realistic system model.  相似文献   
6.
Abstract: An important goal of clinical electrophysiological studies is estimation of the source of rhythm disturbances (arrhythmia) in the heart. 15% of ventricular arrhythmias are known to originate from the outer surface of the heart (epicardium). One localization approach targeting the epicardium uses multielectrode catheters placed in the coronary veins. However, epicardial measurement sites from these catheters are limited to locations reached via the coronary veins. This study investigates the feasibility of several pattern classification and neural network approaches for localization of the source of ventricular arrhythmias from sparse measurements acquired from within coronary veins. Specifically, we studied Kohonen self-organizing maps and fuzzy C-means clustering methods for the construction of the target vector in neural networks from experimental high-resolution activation-time patterns. We also studied two neural network techniques, probabilistic neural networks and backpropagation networks, for the training and test procedures. The results of this study showed that it was possible to localize the arrhythmia source in a relatively small region for approximately 70% of cases. This study, in general, showed that the combination of probabilistic neural networks, Kohonen self-organizing maps and fuzzy C-means clustering approaches is feasible in catheter-based epicardial arrhythmia source localization.  相似文献   
7.
ABSTRACT

Dempster–Shafer (D–S) evidence theory is very efficient and widely used mathematical tool for uncertain and imprecise information fusion for decision making. D–S rule is criticised by many researchers as it gives illogical and counterintuitive results especially when the series of evidence provided by various experts are in a high degree of conflict. Various attempts have been made and several alternatives proposed to this rule. In this paper, a new alternative is proposed which considers the possibility of an error made by experts while providing evidence, calculates the error and incorporates in the revised masses. The validity and efficiency of the proposed approach have been demonstrated with numerous examples and the results are compared with already existing methods.

Highlights
  • An alternative method is proposed to handle the conflicting evidence.

  • An Error In Judgement while gathering evidence is considered and incorporated before combining evidence.

  • The method is simple and gives better and reasonable results than other previous methods when evidence conflicts

  相似文献   
8.
Natural perlite material was added for the first time into a polyester filament yarn structure. The water absorption and heat and sound insulation properties of the fabrics produced from textured and twisted polyester yarns containing 1.25% perlite additive were tested, and the results were compared with those obtained on the fabrics produced from reference polyester yarns. Although there are differences between the mechanical properties of the polyester yarns, the yarns including perlite remained within commercial usage limits. The thermal resistance values of polyester sateen fabrics obtained from perlite‐containing yarns were higher than those of the reference fabrics. The contribution of perlite led to a marked improvement, especially in the hydrophilicity and sound insulation of the polyester fabrics. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43128.  相似文献   
9.
This study assesses the colour, colour difference and colour strength values obtained for eight disperse-dyed polyester fabric samples produced from full and hollow round and trilobal fibres after four sets of abrasion cycle. Each fabric was produced from the same yarns in warp and weft directions. The L *, C *ΔE*ab and K/S values of the undyed fabrics and dyed fabrics before and after increasing cycles of abrasion are presented and discussed. Fabrics produced from full and hollow fibres showed great differences regarding colour values in abrasion behaviour. Fabrics produced from hollow fibres were found to be very sensitive to increasing abrasion cycles.  相似文献   
10.
Tuning and control of color temperature of trichromatic white light emission is demonstrated for the first time from a single ZnCdSSe nanosheet realized by a novel growth method using chemical vapor deposition (CVD). The nanosheets have thicknesses in the range of 60–350 nm and lateral dimensions of tens of micrometers. These nanosheet structures with three or more parallel segments are able to emit the three primary colors of light from a monolithic body and the combination of the emitted light appears as white. Due to temperature dependence of the alloy composition and the spatial profile of the temperature in the CVD chamber, alloy compositions and the widths of individual segments can be controlled by the substrate locations and the growth time, respectively. Such control determines the emission color and relative intensity of each segment, thus resulting in the tuning of the color temperature of the white light, or in the realization of any visible colors. Trichromatic white light emission is demonstrated with the correlated color temperature covering an extensive range from 2700 to 14 400 K using various growth parameters. In addition, a dynamic tuning of colors and color temperature is demonstrated by sweeping a pump beam across a single nanosheet.  相似文献   
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