963 resultados para Praial and estuarine system.


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One of the issues in the innovation system literature is examination of technological learning strategies of laggard nations. Two distinct bodies of literature have contributed to our insight into forces driving learning and innovation, National Systems of Innovation (NSI) and technological learning literature. Although both literatures yield insights on catch-up strategies of 'latecomer' nations, the explanatory powers of each literature by itself is limited. In this paper, a possible way of linking the macro- and the micro-level approaches by incorporating enterprises as active learning entities into the learning and innovation system is proposed. The proposed model has been used to develop research hypotheses and indicate research directions and is relevant for investigating the learning strategies of firms in less technologically intensive industries outside East Asia.

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This paper builds on a Strategic Activity Framework (Jarzabkowski, 2005) and activity based theories of development (Vygotsky, 1978) to model how Enterprise Systems are used to support emerging strategy. It makes three contributions. Firstly, it links fluidity and extensiveness of system use to patterns of strategising. Fluidity - the ability to change system use as needs change - is supported by interactive strategising, where top managers communicate directly with the organisation. Extensiveness requires procedural strategising, embedding system use in structures and routines. Secondly, it relates interactive and procedural strategising to the importance of the system - procedural strategising is more likely to occur if the system is strategically important. Thirdly, using a scaffolding metaphor it identifies patterns in the activities of top managers and Enterprise System custodians, who identify process champions within the organisational community, orient them towards system goals, provide guided support, and encourage fluidity through pacing implementation with learning.© 2013 Published by Elsevier B.V. All rights reserved.

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The accumulation and transport of solutes are hallmarks of osmoadaptation. In this study we have employed the inability of the Saccharomyces cerevisiae gpd1Δ gpd2Δ mutant both to produce glycerol and to adapt to high osmolarity to study solute transport through aquaglyceroporins and the control of osmostress-induced signaling. High levels of different polyols, including glycerol, inhibited growth of the gpd1Δ gpd2Δ mutant. This growth inhibition was suppressed by expression of the hyperactive allele Fps1-AΔ of the osmogated yeast aquaglyceroporin, Fps1. The degree of suppression correlated with the relative rate of transport of the different polyols tested. Transport studies in secretory vesicles confirmed that Fps1-Δ1 transports polyols at increased rates compared with wild type Fps1. Importantly, wild type Fps1 and Fps1-Δ1 showed similarly low permeability for water. The growth defect on polyols in the gpd1Δ gpd2Δ mutant was also suppressed by expression of a heterologous aquaglyceroporin, rat AQP9. We surmised that this suppression was due to polyol influx, causing the cells to passively adapt to the stress. Indeed, when aquaglyceroporin-expressing gpd1Δ gpd2Δ mutants were treated with glycerol, xylitol, or sorbitol, the osmosensing HOG pathway was activated, and the period of activation correlated with the apparent rate of polyol uptake. This observation supports the notion that deactivation of the HOG pathway is closely coupled to osmotic adaptation. Taken together, our "conditional" osmotic stress system facilitates studies on aquaglyceroporin function and reveals features of the osmosensing and signaling system. © 2005 by The American Society for Biochemistry and Molecular Biology, Inc.

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Recent technological advances have paved the way for developing and offering advanced services for the stakeholders in the agricultural sector. A paradigm shift is underway from proprietary and monolithic tools to Internet-based, cloud hosted, open systems that will enable more effective collaboration between stakeholders. This new paradigm includes the technological support of application developers to create specialized services that will seamlessly interoperate, thus creating a sophisticated and customisable working environment for the end users. We present the implementation of an open architecture that instantiates such an approach, based on a set of domain independent software tools called "generic enablers" that have been developed in the context of the FI-WARE project. The implementation is used to validate a number of innovative concepts for the agricultural sector such as the notion of a services' market place and the system's adaptation to network failures. During the design and implementation phase, the system has been evaluated by end users, offering us valuable feedback. The results of the evaluation process validate the acceptance of such a system and the need of farmers to have access to sophisticated services at affordable prices. A summary of this evaluation process is also presented in this paper. © 2013 Elsevier B.V.

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The primary purpose of this research is to study the linkage between perceived job design characteristics and information system environment characteristics before and after the replacement of a legacy information system with a new type of information system (referred to as an Enterprise Resource Planning or ERP system). A public state University implementing an academic version of an ERP system was selected for the study. Three survey instruments were used to examine the perception of the information system, the job characteristics, and the organizational culture before and after the system implementation. The research participants included two large departments resulting in a sample of 130 workers. Research questions were analyzed using multivariate procedures including factor analysis, path analysis, step-wise regression, and matched pair analysis. ^ Results indicated that the ERP system has introduced new elements into the working environment that has changed the perception of how the job design characteristics and organization culture dimensions are viewed by the workers. The understanding of how the perceived system characteristics align with an individual's perceived job design characteristics is supported by each of the system characteristics significantly correlated in the proposed direction. The stronger support of this relationship becomes visible in the causal flow of the effects seen in the path diagram and in the step-wise regression. The perceived job design characteristics aligning with dimensions of organizational culture are not as strong as the literature suggests. Although there are significant correlations between the job and culture variables, only one relationship can be seen in the causal flow. ^ This research has demonstrated that system characteristics of ERP do contribute to the perception of change in an organization and do support organizational culture behaviors and job characteristics. ^

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Next-generation integrated wireless local area network (WLAN) and 3G cellular networks aim to take advantage of the roaming ability in a cellular network and the high data rate services of a WLAN. To ensure successful implementation of an integrated network, many issues must be carefully addressed, including network architecture design, resource management, quality-of-service (QoS), call admission control (CAC) and mobility management. ^ This dissertation focuses on QoS provisioning, CAC, and the network architecture design in the integration of WLANs and cellular networks. First, a new scheduling algorithm and a call admission control mechanism in IEEE 802.11 WLAN are presented to support multimedia services with QoS provisioning. The proposed scheduling algorithms make use of the idle system time to reduce the average packet loss of realtime (RT) services. The admission control mechanism provides long-term transmission quality for both RT and NRT services by ensuring the packet loss ratio for RT services and the throughput for non-real-time (NRT) services. ^ A joint CAC scheme is proposed to efficiently balance traffic load in the integrated environment. A channel searching and replacement algorithm (CSR) is developed to relieve traffic congestion in the cellular network by using idle channels in the WLAN. The CSR is optimized to minimize the system cost in terms of the blocking probability in the interworking environment. Specifically, it is proved that there exists an optimal admission probability for passive handoffs that minimizes the total system cost. Also, a method of searching the probability is designed based on linear-programming techniques. ^ Finally, a new integration architecture, Hybrid Coupling with Radio Access System (HCRAS), is proposed for lowering the average cost of intersystem communication (IC) and the vertical handoff latency. An analytical model is presented to evaluate the system performance of the HCRAS in terms of the intersystem communication cost function and the handoff cost function. Based on this model, an algorithm is designed to determine the optimal route for each intersystem communication. Additionally, a fast handoff algorithm is developed to reduce the vertical handoff latency.^

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With the recent explosion in the complexity and amount of digital multimedia data, there has been a huge impact on the operations of various organizations in distinct areas, such as government services, education, medical care, business, entertainment, etc. To satisfy the growing demand of multimedia data management systems, an integrated framework called DIMUSE is proposed and deployed for distributed multimedia applications to offer a full scope of multimedia related tools and provide appealing experiences for the users. This research mainly focuses on video database modeling and retrieval by addressing a set of core challenges. First, a comprehensive multimedia database modeling mechanism called Hierarchical Markov Model Mediator (HMMM) is proposed to model high dimensional media data including video objects, low-level visual/audio features, as well as historical access patterns and frequencies. The associated retrieval and ranking algorithms are designed to support not only the general queries, but also the complicated temporal event pattern queries. Second, system training and learning methodologies are incorporated such that user interests are mined efficiently to improve the retrieval performance. Third, video clustering techniques are proposed to continuously increase the searching speed and accuracy by architecting a more efficient multimedia database structure. A distributed video management and retrieval system is designed and implemented to demonstrate the overall performance. The proposed approach is further customized for a mobile-based video retrieval system to solve the perception subjectivity issue by considering individual user's profile. Moreover, to deal with security and privacy issues and concerns in distributed multimedia applications, DIMUSE also incorporates a practical framework called SMARXO, which supports multilevel multimedia security control. SMARXO efficiently combines role-based access control (RBAC), XML and object-relational database management system (ORDBMS) to achieve the target of proficient security control. A distributed multimedia management system named DMMManager (Distributed MultiMedia Manager) is developed with the proposed framework DEMUR; to support multimedia capturing, analysis, retrieval, authoring and presentation in one single framework.

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Estuaries and estuarine wetlands are ecologically and societally important systems, exhibiting high rates of primary production that fuel offshore secondary production. Hydrological processes play a central role in shaping estuarine ecosystem structure and function by controlling nutrient loading and the relative contributions of marine and terrestrial influences on the estuary. The Comprehensive Everglades Restoration Plan includes plans to restore freshwater delivery to Taylor Slough, a shallow drainage basin in the southern Everglades, ultimately resulting in increased freshwater flow to the downstream Taylor River estuary. The existing seasonal and inter-annual variability of water flow and source in Taylor River affords the opportunity to investigate relationships between ecosystem function and hydrologic forcing. Estimates of aquatic ecosystem metabolism, derived from free-water, diel changes in dissolved oxygen, were combined with assessments of wetland flocculent detritus quality and transport within the context of seasonal changes in Everglades hydrology. Variation in ecosystem gross primary production and respiration were linked to seasonal changes in estuarine water quality using multiple autoregression models. Furthermore, Taylor River was observed to be net heterotrophic, indicating that an allochthonous source of carbon maintained ecosystem respiration in excess of autochthonous primary production. Wetland-derived detritus appears to be an important vector of energy and nutrients across the Everglades landscape; and in Taylor River, is seasonally flushed into ponded segments of the river where it is then respired. Lastly, seasonal water delivery appears to govern feedbacks regulating water column phosphorus availability in the Taylor River estuary.

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South Florida’s watersheds have endured a century of urban and agricultural development and disruption of their hydrology. Spatial characterization of South Florida’s estuarine and coastal waters is important to Everglades’ restoration programs. We applied Factor Analysis and Hierarchical Clustering of water quality data in tandem to characterize and spatially subdivide South Florida’s coastal and estuarine waters. Segmentation rendered forty-four biogeochemically distinct water bodies whose spatial distribution is closely linked to geomorphology, circulation, benthic community pattern, and to water management. This segmentation has been adopted with minor changes by federal and state environmental agencies to derive numeric nutrient criteria.

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Modern IT infrastructures are constructed by large scale computing systems and administered by IT service providers. Manually maintaining such large computing systems is costly and inefficient. Service providers often seek automatic or semi-automatic methodologies of detecting and resolving system issues to improve their service quality and efficiency. This dissertation investigates several data-driven approaches for assisting service providers in achieving this goal. The detailed problems studied by these approaches can be categorized into the three aspects in the service workflow: 1) preprocessing raw textual system logs to structural events; 2) refining monitoring configurations for eliminating false positives and false negatives; 3) improving the efficiency of system diagnosis on detected alerts. Solving these problems usually requires a huge amount of domain knowledge about the particular computing systems. The approaches investigated by this dissertation are developed based on event mining algorithms, which are able to automatically derive part of that knowledge from the historical system logs, events and tickets. ^ In particular, two textual clustering algorithms are developed for converting raw textual logs into system events. For refining the monitoring configuration, a rule based alert prediction algorithm is proposed for eliminating false alerts (false positives) without losing any real alert and a textual classification method is applied to identify the missing alerts (false negatives) from manual incident tickets. For system diagnosis, this dissertation presents an efficient algorithm for discovering the temporal dependencies between system events with corresponding time lags, which can help the administrators to determine the redundancies of deployed monitoring situations and dependencies of system components. To improve the efficiency of incident ticket resolving, several KNN-based algorithms that recommend relevant historical tickets with resolutions for incoming tickets are investigated. Finally, this dissertation offers a novel algorithm for searching similar textual event segments over large system logs that assists administrators to locate similar system behaviors in the logs. Extensive empirical evaluation on system logs, events and tickets from real IT infrastructures demonstrates the effectiveness and efficiency of the proposed approaches.^

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Increasing atmospheric carbon dioxide threatens to decrease pH in the world's oceans. Coastal and estuarine calcifying organisms of significant ecological and economical importance are at risk; however, several biogeochemical processes drive pH in these habitats. In particular, coastal and estuarine sediments are frequently undersaturated with respect to calcium carbonate due to high rates of organic matter remineralization, even when overlying waters are saturated. As a result, the post-larval stages of infaunal marine bivalves must be able to deposit new shell material in conditions that are corrosive to shell. We measured calcification rates on the hard clam, Mercenaria spp.,in 5 post-larval size classes (0.39, 0.56, 0.78, 0.98, and 2.90 mm shell height) using the alkalinity anomaly method. Acidity of experimental water was controlled by bubbling with air-CO2 blends to obtain pH values of 8.02, 7.64, and 7.41, corresponding to pCO2 values of 424, 1120, and 1950 µatm. These pH values are typical of those found in many near-shore terrigenous marine sediments. Our results show that calcification rate decreased with lower pH in all 5 size classes measured. We also found a significant effect of size on calcification rate, with the smaller post-larval sizes unable to overcome dissolution pressure. Increased calcification rate with size allowed the larger sizes to overcome dissolution pressure and deposit new shell material under corrosive conditions. Size dependency of pH effects on calcification is likely due to organogenesis and developmental shifts in shell mineralogy occurring through the post-larval stage. Furthermore, we found significantly different calcification rates between the 2 sources of hard clams we used for these experiments, most likely due to genotypic differences. Our findings confirm the susceptibility of the early life stages of this important bivalve to decreasing pH and reveal mechanisms behind the increased mortality in post-larval juvenile hard clams related to dissolution pressure, that has been found in previous studies.

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The combination of elevated CO2 and the increased acidity in surface oceans is likely to have an impact on photosynthesis via its effects on inorganic carbon speciation and on the overall energetics of phytoplankton. Exposure to UV radiation (UVR) may also have a role in the response to elevated CO2 and acidification, due to the fact that UVR may variously impact on photosynthesis and because of the energy demand of UVR defense. The cell may gain energy by down-regulating the CO2 concentrating mechanism, which may lead to a greater ability to cope with UVR and/or higher growth rates. In order to clarify the interplay of cell responses to increasing CO2 and UVR, we investigated the photosynthetic response of the marine and estuarine diatom Cylindrotheca closterium f. minutissima cultured at either 390 (ambient) or 800 (elevated) ppmv CO2, while exposed to solar radiation with or without UVR (UVR, 280-400 nm). After a 6 day acclimation period, the growth rate of cells was little affected by elevated CO2 and no obvious correlation with the radiation dose (for both PAR and PAR + UV treatments) could be detected. However, the relative electron transport rate was reduced and was more sensitive to UVR in cells main - tained at elevated CO2 as compared to cells cultured at ambient CO2. The CO2 concentrating mechanism was down regulated at 800 ppmv CO2, but was apparently not completely switched off. These data are discussed with respect to their significance in the context of global climate change.

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This talk explores how the runtime system and operating system can leverage metrics that express the significance and resilience of application components in order to reduce the energy footprint of parallel applications. We will explore in particular how software can tolerate and indeed exploit higher error rates in future processors and memory technologies that may operate outside their safe margins.

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[EN]Facial image processing is becoming widespread in human-computer applications, despite its complexity. High-level processes such as face recognition or gender determination rely on low-level routines that must e ectively detect and normalize the faces that appear in the input image. In this paper, a face detection and normalization system is described. The approach taken is based on a cascade of fast, weak classi ers that together try to determine whether a frontal face is present in the image.

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During the development of a new treatment space for the UK emergency ambulance participatory observations with front-line clinicians revealed the need for an integrated patient monitoring, communication and navigation system. The research identified the different information touch-points and requirements through modes of use analysis, day-in-the-life study and simulation workshops with clinicians. Emergency scenario and role-play with paramedics identified 5 distinct ambulance modes of use. Information flow diagrams were created and checked by paramedics and digital User Interface (UI) wireframes were developed and evaluated by clinicians during clinical evaluations. Feedback from clinicians defined UI design specification further leading to a final design proposal. This research was a further development from the 2007 EPSRC funded “Smart Pods” project. The resulting interactive prototype was co-designed in collaboration with ambulance crews and provides a vision of what could be achieved by integrating well-proven IT technologies and protocols into a package relevant in the emergency medicine field. The system has been reviewed by over 40 ambulance crews and is part of a newly co-designed ambulance treatment space.