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91.
Highly Efficient Perovskite Nanocrystal Light‐Emitting Diodes Enabled by a Universal Crosslinking Method
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92.
93.
Tomás Sánchez López Damith Chinthana Ranasinghe Bela Patkai Duncan McFarlane 《Information Systems Frontiers》2011,13(2):281-300
Deployment of embedded technologies is increasingly being examined in industrial supply chains as a means for improving efficiency
through greater control over purchase orders, inventory and product related information. Central to this development has been
the advent of technologies such as bar codes, Radio Frequency Identification (RFID) systems, and wireless sensors which when
attached to a product, form part of the product’s embedded systems infrastructure. The increasing integration of these technologies
dramatically contributes to the evolving notion of a “smart product”, a product which is capable of incorporating itself into
both physical and information environments. The future of this revolution in objects equipped with smart embedded technologies
is one in which objects can not only identify themselves, but can also sense and store their condition, communicate with other
objects and distributed infrastructures, and take decisions related to managing their life cycle. The object can essentially
“plug” itself into a compatible systems infrastructure owned by different partners in a supply chain. However, as in any development
process that will involve more than one end user, the establishment of a common foundation and understanding is essential
for interoperability, efficient communication among involved parties and for developing novel applications. In this paper,
we contribute to creating that common ground by providing a characterization to aid the specification and construction of
“smart objects” and their underlying technologies. Furthermore, our work provides an extensive set of examples and potential
applications of different categories of smart objects. 相似文献
94.
Filip Goldefus Tomáš Masopust Alexander Meduna 《Theoretical computer science》2010,411(40-42):3661-3667
A left-forbidding grammar, introduced in this paper, is a context-free grammar, where a set of nonterminal symbols is attached to each context-free production. Such a production can rewrite a nonterminal provided that no symbol from the attached set occurs to the left of the rewritten nonterminal in the current sentential form. The present paper discusses cooperating distributed grammar systems with left-forbidding grammars as components and gives some new characterizations of language families of the Chomsky hierarchy. In addition, it also proves that twelve nonterminals are enough for cooperating distributed grammar systems working in the terminal derivation mode with two left-forbidding components (including erasing productions) to characterize the family of recursively enumerable languages. 相似文献
95.
An adaptive, real-time, traffic monitoring system 总被引:1,自引:0,他引:1
In this paper we describe a computer vision-based traffic monitoring system able to detect individual vehicles in real-time.
Our fully integrated system first obtains the main traffic variables: counting, speed and category; and then computes a complete
set of statistical variables. The objective is to investigate some of the difficulties impeding existing traffic systems to
achieve balanced accuracy in every condition; i.e. day and night transitions, shadows, heavy vehicles, occlusions, slow traffic
and congestions. The system we present is autonomous, works for long periods of time without human intervention and adapts
automatically to the changing environmental conditions. Several innovations, designed to deal with the above circumstances,
are proposed in the paper: an integrated calibration and image rectification step, differentiated methods for day and night,
an adaptive segmentation algorithm, a multistage shadow detection method and special considerations for heavy vehicle identification
and treatment of slow traffic. A specific methodology has been developed to benchmark the accuracy of the different methods
proposed. 相似文献
96.
Pooneh Bagheri Zadeh Akbar Sheikh Akbari Tom Buggy John Soraghan 《Multimedia Tools and Applications》2010,49(2):347-370
In this paper a novel multiresolution human visual system and statistically based image coding scheme is presented. It decorrelates
the input image into a number of subbands using a lifting based wavelet transform. The codec employs a novel statistical encoding
algorithm to code the coefficients in the detail subbands. Perceptual weights are applied to regulate the threshold value
of each detail subband that is required in the statistical encoding process. The baseband coefficients are losslessly coded.
An extension of the codec to the progressive transmission of images is also developed. To evaluate the performance of the
coding scheme, it was applied to a number of test images and its performance with and without perceptual weights is evaluated.
The results indicate significant improvement in both subjective and objective quality of the reconstructed images when perceptual
weights are employed. The performance of the proposed technique was also compared to JPEG and JPEG2000. The results show that
the proposed coding scheme outperforms both coding standards at low compression ratios, while offering satisfactory performance
at higher compression ratios. 相似文献
97.
Tom Kontogiannis 《Cognition, Technology & Work》2010,12(2):103-118
Distributed supervisory control systems often rely on complex and centralized plans to cope with a variety of unanticipated
situations. Replanning requires practitioners to forgo standard procedures in favor of making simple plans without simplifying,
managing task coupling, and anticipating team needs to provide decentralized and elaborate plans. This article proposes a
plan classification scheme to study what features of plans facilitate or hinder adaptation and a framework to examine how
features of plans influence the cognitive processes of replanning. The plan features have been assigned to the categories
of plan complexity, coupling, and control. Plans are task networks sharing similar features of complexity and coupling to
technical systems. The proposed framework sets out to explore how plan features influence the processes of recognizing plan
disruptions, reviewing challenges and different team stances, repairing plans to resolve new risks, and reacting by coordinating
team efforts to execute plans. The framework draws on the Extended Control Model (ECOM) to integrate the four processes of
replanning into a set of control loops. The benefits of this framework are illustrated in the context of operator training
and decision support. 相似文献
98.
99.
Yongjun Shen Elke Hermans Da Ruan Geert Wets Tom Brijs Koen Vanhoof 《Expert systems with applications》2011,38(12):15262-15272
Data envelopment analysis (DEA) is a powerful analytical research tool for measuring the relative efficiency of a homogeneous set of decision making units (DMUs) by obtaining empirical estimates of relations between multiple inputs and multiple outputs related to the DMUs. To further embody multilayer hierarchical structures of these inputs and outputs in the DEA framework, which are prevalent in today’s performance evaluation activities, we propose a generalized multiple layer DEA (MLDEA) model. Starting from the input-oriented CCR model, we elaborate the mathematical deduction process of the MLDEA model, formulate the weights in each layer of the hierarchy, and indicate different types of possible weight restrictions. Meanwhile, its linear transformation is realized and further extended to the BCC form. To demonstrate the proposed MLDEA model, a case study in evaluating the road safety performance of a set of 19 European countries is carried out. By using 13 hierarchical safety performance indicators in terms of road user behavior (e.g., inappropriate or excessive speed) as the model’s input and 4 layered road safety final outcomes (e.g., road fatalities) as the output, we compute the most optimal road safety efficiency score for the set of European countries, and further analyze the weights assigned to each layer of the hierarchy. A comparison of the results with the ones from the one layer DEA model clearly indicates the usefulness and effectiveness of this improvement in dealing with a great number of performance evaluation activities with hierarchical structures. 相似文献
100.
Tom Oomen Author Vitae Jeroen van de Wijdeven Author Vitae Author Vitae 《Automatica》2009,45(4):981-1666
Iterative Learning Control (ILC) is a control strategy to improve the performance of digital batch repetitive processes. Due to its digital implementation, discrete time ILC approaches do not guarantee good intersample behavior. In fact, common discrete time ILC approaches may deteriorate the intersample behavior, thereby reducing the performance of the sampled-data system. In this paper, a generally applicable multirate ILC approach is presented that enables to balance the at-sample performance and the intersample behavior. Furthermore, key theoretical issues regarding multirate systems are addressed, including the time-varying nature of the multirate ILC setup. The proposed multirate ILC approach is shown to outperform discrete time ILC in realistic simulation examples. 相似文献