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1.
An electrically conductive plastic material was obtained by the polymerization of pyrrole on insulating polymeric materials
and nylon cloth impregnated with the oxidant by vapour phase technique, resulting in a uniform, smooth and adherent coating
of conducting polymer having a surface resistance ranging from 200 Ω/□ to 20 kΩ/□, which makes it suitable for applications
as an antistatic material. 相似文献
2.
In recent years, active learning has emerged as a powerful tool in building robust systems for object detection using computer vision. Indeed, active learning approaches to on-road vehicle detection have achieved impressive results. While active learning approaches for object detection have been explored and presented in the literature, few studies have been performed to comparatively assess costs and merits. In this study, we provide a cost-sensitive analysis of three popular active learning methods for on-road vehicle detection. The generality of active learning findings is demonstrated via learning experiments performed with detectors based on histogram of oriented gradient features and SVM classification (HOG–SVM), and Haar-like features and Adaboost classification (Haar–Adaboost). Experimental evaluation has been performed on static images and real-world on-road vehicle datasets. Learning approaches are assessed in terms of the time spent annotating, data required, recall, and precision. 相似文献
3.
4.
The dc photocurrents generated by steady-state moving space-charge fields inside photoconductive semiconductors containing deep level donors and traps can be used to determine the relative frequency differences between the two interfering optical fields that establish the space-charge fields. A simple laser velocimeter that uses a semi-insulating GaAs:Cr sample to detect the Doppler frequency shift between two laser beams is demonstrated. 相似文献
5.
Cyclic GMP (cGMP) is a crucial intracellular messenger in neuronal, muscle, and endocrine cells. The intracellular concentration of cGMP is regulated by various neurotransmitters, including acetylcholine (ACh) and nitric oxide (NO). While much is known about the biochemical steps leading to cGMP synthesis, little is known about cGMP kinetics in intact cells. Here, we use "patch-cramming," in which an excised, inside-out membrane patch containing cyclic nucleotide-gated ion channels is used as a biosensor, to obtain the first real-time measurements of cGMP in intact cells. Patch-cramming experiments on neuroblastoma cells show that both muscarinic agonists and NO rapidly elevate cGMP. NO elicits cGMP responses repeatedly without decrement, whereas responses to muscarinic agonists exhibit a profound and prolonged desensitization. Remarkably, muscarinic agonists also cause long-term (>30 min) suppression (LTS) of cGMP responses elicited by NO. Biochemical measurements reveal that rat sympathetic neurons also exhibit LTS of cGMP, suggesting that LTS is a widespread mechanism that may contribute to synaptic plasticity. 相似文献
6.
7.
Real-time three-dimensional tracking of people is an important requirement for a growing number of applications. In this
paper we describe two trackers; both of them use a network of video cameras for person tracking. These trackers are called
a rectilinear video array tracker (R-VAT) and an omnidirectional video array tracker (O-VAT), indicating the two different
ways of video capture. The specific objectives of this paper are twofold: (i) to present a systematic comparison of these
two trackers using an extensive series of experiments conducted in an `intelligent' room; (ii) to develop a real-time system
for tracking the head and face of a person, as an extension of the O-VAT approach. The comparative research indicates that
O-VAT is more robust to the number of people, less complex and runs faster, needs manual camera calibration, and the integrated
omnidirectional video network has better reconfigurability. The person head and face tracker study shows that such a system
can serve as a most effective input stage for face recognition and facial expression analysis modules. 相似文献
8.
9.
Shefali Trivedi Yashwant Mehta K. Chandra P.S. Mishra 《Journal of Materials Processing Technology》2010,210(1):85-90
The present investigation shows the role of chromium in Fe–P binary and Fe–P–Cr ternary alloys. The compositions are characterized in terms of microstructure, porosity content, hardness and tensile properties. The alloys were made using a hot powder forging technique. In this process mild steel encapsulated powders were hot forged into slabs. Then the slabs were hot rolled and annealed to relieve the residual stresses. Densifications as high as 98.9% of theoretical density have been realized. Microstructures of these alloys consist of single-phase ferrite only. Both Fe–0.45P and Fe–0.45P–3Cr alloys showed very high strength. As forged and hot rolled Fe–0.45P alloy showed low elongation. It was observed that, the addition of Cr to Fe–P based alloys caused an increase in strength associated with the reduction in ductility. Alloys developed in the present investigation were capable of hot working to very thin gage of sheets and wires. 相似文献
10.
Energy management system (EMS) computer architectures have changed significantly over the recent past increasing the difficulty and the need for a priori assessment of system performance and dependability. The old practice based on measurements is no longer acceptable because of the flexibility accrued with the deployment of the new distributed computer-based systems. The number of “what if” questions increased since EMS systems are now implemented using multiple workstations that can be interconnected in various different ways.In this paper we show how alternative configurations can be modeled and analyzed, before proposing and purchasing any equipment, with the assistance of Markov reward models. We review the concept of Markov reward models and show how they can be applied in the availability analysis of SCADA/EMS computer systems. The paper also presents a software tool that facilitates automatic generation and solution of large Markov reward models. The input language of this modeling tool uses a variation of stochastic Petri nets called stochastic reward nets, which are also reviewed. We believe this is the first time a detailed quantitative model of a SCADA/EMS computer system is proposed and solved in the general literature. 相似文献