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951.
International Journal on Document Analysis and Recognition (IJDAR) - This work focuses on the layout analysis of historical handwritten registers, in which local religious ceremonies were recorded....  相似文献   
952.
Users of mobile devices can nowadays easily create large quantities of mobile multimedia documents tracing significant events attended, places visited or, simply, moments of their everyday life. However, they face the challenge of organizing these documents in order to facilitate searching through them at a later time and sharing them with other users. We propose using context awareness and semantic technologies in order to improve and facilitate the organization, annotation, retrieval and sharing of personal mobile multimedia documents. Our approach combines metadata extracted and enriched automatically from the users’ context with annotations provided manually by the users and with annotations inferred by applying user-defined rules to context features. These new contextual metadata are integrated into the processes of annotation, sharing and keyword-based retrieval.  相似文献   
953.
Securing group communication in wireless sensor networks has recently been extensively investigated. Many works have addressed this issue, and they have considered the grouping concept differently. In this paper, we consider a group as being a set of nodes sensing the same data type, and we alternatively propose an efficient secure group communication scheme guaranteeing secure group management and secure group key distribution. The proposed scheme (RiSeG) is based on a logical ring architecture, which permits to alleviate the group controller’s task in updating the group key. The proposed scheme also provides backward and forward secrecy, addresses the node compromise attack, and gives a solution to detect and eliminate the compromised nodes. The security analysis and performance evaluation show that the proposed scheme is secure, highly efficient, and lightweight. A comparison with the logical key hierarchy is preformed to prove the rekeying process efficiency of RiSeG. Finally, we present the implementation details of RiSeG on top of TelosB sensor nodes to demonstrate its feasibility.  相似文献   
954.
This study presents a new simulation game and analyzes its impact on operations management education. The proposed simulation was empirically tested by comparing the number of mistakes during the first and second halves of the game. Data were gathered from 100 teams of four or five undergraduate students in business administration, taking their first course in operations management. To assess learning, instead of relying solely on an overall performance measurement, as is usually done in the skill-based learning literature, we analyzed the evolution of different types of mistakes that were made by students in successive rounds of play. Our results show that although simple decision-making skills can be acquired with traditional teaching methods, simulation games are more effective when students have to develop decision-making abilities for managing complex and dynamic situations.  相似文献   
955.
The performance of a conventional sequence (pre-ozonation, coagulation/ flocculation/ sedimentation, filtration, disinfection) and two non-conventional sequences (pre-ozonation, nanofiltration; and pre-ozonation, coagulation/ flocculation/ sedimentation, nanofiltration) on the removal of natural organic matter (NOM) and disinfection by-products (DBPs) formation potential was evaluated. Raw and treated waters were characterized in terms of molecular weight, which includes the amount of NOM removed and the qualitative changes in the NOM characteristics (molecular weight and hydrophobicity) since they could be directly related with the DBPs formation. The results demonstrate that, for the type of raw water analysed (hydrophilic with low dissolved organic carbon content, 0.99 L/(mg.m) and 1.31 mg DOC/L), both treatment sequences remove larger molecular weight compounds (>1,900 g/mol). Treated waters have the dominant fractions in the smaller molecular size fractions (<750 g/mol). However, the sequences with nanofiltration have a higher percentage of low molecular weight compounds removed (between 430 and 250 g/mol), when compared with conventional sequence, thus the water from nanofiltration sequences will have lower DBPs formation potential. The removal of the smallest molecular size fractions can be enhanced by optimising the water treatment process and the quality of water will improve relating with DBPs formation.  相似文献   
956.
Holonic multiagent systems (HMAS) offer a promising software engineering approach for developing complex open software systems. However the process of building Multi-Agent Systems (MAS) and HMAS is mostly different from the process of building more traditional software systems as it introduces new design and development challenges. This paper introduces an agent-oriented software process for engineering complex systems called ASPECS. ASPECS is based on a holonic organisational metamodel and provides a step-by-step guide from requirements to code allowing the modelling of a system at different levels of details using a set of refinement methods. This paper details the entire ASPECS development process and provides a set of methodological guidelines for each process activity. A complete case study is also used to illustrate the design process and the associated notations. ASPECS uses UML as a modelling language. Because of the specific needs of agents and holonic organisational design, the UML semantics and notation are used as reference points, but they have been extended by introducing new specific profiles.  相似文献   
957.
958.
A methodology to thoroughly characterize an electric near‐field probe based on small dipole antenna is presented. Both theoretical investigations and experimental direct measurements determine the various characteristics of the probe such as selectivity, sensitivity and spatial resolution. Results show the efficiency of the probe for diagnosing electromagnetic phenomena. © 2008 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2008.  相似文献   
959.
Bom Jardim brook is a small stream that flows through an area under the influence of a Petrochemical Complex, demanding control over its quality, so a genotoxic evaluation was performed. This study was conducted in situ, based on previous analysis on the same subject. These were performed both in vitro, with Salmonella typhimurium and human lymphocytes, and in vivo, using bioassays with fish exposed to water from the study area. The purpose of this research was to assess the quality of the aquatic environment and possible effects from petrochemical pollution to surrounding native populations. Micronuclei (MNE) and nuclear abnormalities (NA) frequencies in peripheral blood of Astyanax jacuhiensis, a native fish species collected from the study area, were used as biomarkers. Study period was from summer/99 to spring/2001, using samples obtained seasonally at two ponds upstream from the industrial area (BJN and BJPa) and two sites in Bom Jardim brook (BJ002 and BJ000), which are subject to Complex influence. MNE and NA frequencies found in individuals from BJ002 and BJ000 were similar, showing positive genotoxic responses related to control sites BJN and BJPa. No differential sensitivity could be verified for micronuclei induction between genders of A. jacuhiensis in the studied population. This study showed that sites subject to petrochemical influence were under higher genotoxic impact. Biomarkers adequacy to the case and the sensitivity of A. jacuhiensis for water monitoring could be also inferred.  相似文献   
960.
In order to face excess waste activated sludge management problems, sludge anaerobic digestion with thermal pre-treatment is of great interest. If most of works agree on the optimal treatment temperature (160–180 °C), results of thermal pre-treatments in terms of biogas production are very dispersed. With the aim of analysing the impact of sludge samples, thermal pre-treatments were carried on five different waste activated sludge samples.

For temperatures lower than 200 °C, COD solubilisation was found to increase linearly with treatment temperature and all the different sludge samples behaved in the same way. For temperatures lower than 150 °C, carbohydrates solubilisation was more important than proteins solubilisation. Analyses of sludge apparent viscosity, settleabilty and dewaterability (CST) of pre-treated sludge pointed out a threshold temperature of 150 °C. Thermal treatments up to 190 °C allowed the biogas production to increase during batch anaerobic digestion of sludge. Biogas volume enhancement was linked to sludge COD solubilisation and to untreated sludge initial biodegradability; the lower the initial biodegradability, the higher is the impact of thermal treatment.  相似文献   

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