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71.
72.
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
73.
Pablo Quintía Roberto Iglesias Miguel A. Rodríguez Carlos V. Regueiro 《Robotics and Autonomous Systems》2010,58(12):1306-1315
One of the main problems of robots is the lack of adaptability and the need for adjustment every time the robot changes its working place. To solve this, we propose a learning approach for mobile robots using a reinforcement-based strategy and a dynamic sensor-state mapping. This strategy, practically parameterless, minimises the adjustments needed when the robot operates in a different environment or performs a different task.Our system will simultaneously learn the state space and the action to execute on each state. The learning algorithm will attempt to maximise the time before a robot failure in order to obtain a control policy suited to the desired behaviour, thus providing a more interpretable learning process. The state representation will be created dynamically, starting with an empty state space and adding new states as the robot finds new situations that has not seen before. A dynamic creation of the state representation will avoid the classic, error-prone and cyclic process of designing and testing an ad hoc representation. We performed an exhaustive study of our approach, comparing it with other classic strategies. Unexpectedly, learning both perception and action does not increase the learning time. 相似文献
74.
Alfonso Rodríguez Ignacio García-Rodríguez de Guzmán Eduardo Fernández-Medina Mario Piattini 《Information and Software Technology》2010,52(9):945-971
ContextModel-Driven Development (MDD) is an alternative approach for information systems development. The basic underlying concept of this approach is the definition of abstract models that can be transformed to obtain models near implementation. One fairly widespread proposal in this sphere is that of Model Driven Architecture (MDA). Business process models are abstract models which additionally contain key information about the tasks that are being carried out to achieve the company’s goals, and two notations currently exist for modelling business processes: the Unified Modelling Language (UML), through activity diagrams, and the Business Process Modelling Notation (BPMN).ObjectiveOur research is particularly focused on security requirements, in such a way that security is modelled along with the other aspects that are included in a business process. To this end, in earlier works we have defined a metamodel called secure business process (SBP), which may assist in the process of developing software as a source of highly valuable requirements (including very abstract security requirements), which are transformed into models with a lower abstraction level, such as analysis class diagrams and use case diagrams through the approach presented in this paper.MethodWe have defined all the transformation rules necessary to obtain analysis class diagrams and use case diagrams from SBP, and refined them through the characteristic iterative process of the action-research method.ResultsWe have obtained a set of rules and a checklist that make it possible to automatically obtain a set of UML analysis classes and use cases, starting from SBP models. Our approach has additionally been applied in a real environment in the area of the payment of electrical energy consumption.ConclusionsThe application of our proposal shows that our semi-automatic process can be used to obtain a set of useful artifacts for software development processes. 相似文献
75.
Humanitarian Non-Governmental Organisations (NGOs) play a growing role in the response to natural disasters, but despite being largely demanded, there is no available decision support system (DSS) specifically designed to address their problem. In this paper we present a decision support system (DSS) to aid those Humanitarian NGOs concerned with the response to natural disasters. Such a DSS has been designed avoiding sophisticated methodologies that may exceed the infrastructural requirements and constraints of emergency management by NGOs. A data-based, two-level knowledge methodology which allows damage assessment of multiple disaster scenarios is presented in order to address that problem. Validation results show viability of our approach. 相似文献
76.
77.
Marta Alberti Joaquim Ciurana Ciro A. Rodríguez Tugrul Özel 《Journal of Intelligent Manufacturing》2011,22(2):263-277
Economic globalization, together with heightened market competition and increasingly short product life cycles are motivating
companies to use advanced manufacturing technologies. Use of high speed machining is increasingly widespread; however, as
the technology is relatively new, it lacks a deep-rooted knowledge base which would facilitate implementation. One of the
most frequent problems facing companies wishing to adopt this technology is selecting the most appropriate machine tool for
the product in question and own enterprise characteristics. This paper presents a decision support system for high speed milling
machine tool selection based on machine characteristics and performance tests. Profile machining tests are designed and conducted
in participating machining centers. The decision support system is based on product dimension accuracy, process parameters
such as feed rate and interpolation scheme used by CNC and machine characteristics such as machine accuracy and cost. Experimental
data for process error and cycle operation time are obtained from profile machining tests with different geometrical feature
zones that are often used in manufacturing of discrete parts or die/moulds. All those input parameters have direct impact
on productivity and manufacturing cost. Artificial neural network models are utilized for decision support system with reasonable
prediction capability. 相似文献
78.
We present a compiler that can be used to automatically obtain efficient Java implementations of parsing algorithms from formal specifications expressed as parsing schemata. The system performs an analysis of the inference rules in the input schemata in order to determine the best data structures and indexes to use, and to ensure that the generated implementations are efficient. The system described is general enough to be able to handle all kinds of schemata for different grammar formalisms, such as context‐free grammars and tree‐adjoining grammars, and it provides an extensibility mechanism allowing the user to define custom notational elements. This compiler has proven very useful for analyzing, prototyping and comparing natural‐language parsers in real domains, as can be seen in the empirical examples provided at the end of the paper. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
79.
MVB (Multifunction Vehicle Bus), defined in IEC 61375, has been broadly adopted as the communication standard between embedded control systems on-board modern trains. In this work a new method to take advantage of the full bandwidth of the channel using an OFDM technique is described. With this new method it is possible to share the physical medium between standard MVB traffic and new OFDM traffic. A 90 Mbps theoretical bitrate can be achieved. The results of this work have been validated in a test bench including standard MVB nodes transmitting on a line similar to a real vehicle bus. 相似文献
80.