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1.
Orji Cyril U. Adjeroh Donald A. Bobbie Patrick O. Nwosu Kingsley C. 《Multimedia Tools and Applications》1998,6(1):5-32
Recent advances in computing technology have brought multimedia information processing to prominence. The ability to digitize, store, retrieve, process, and transport analog information in digital form has changed the dimensions of information handling. Several architectural and network configurations have been proposed for efficient and reliable digital video delivery systems. However, these proposals succeed only in addressing subsets of the whole problem. In this paper, we discuss the characteristics of video services. These include Cable Television, Pay-Per-View, and Video Repository Centers. We also discuss requirements for Video On Demand services. With respect to these video services, we analyze two important video properties: image quality and response time. We discuss and present configurations of a Digital Video Delivery System (DVDS) from three general system components - servers, clients, and connectivities. Pertinent issues in developing each component are also analyzed. We also present an architecture of a DVDS that can support the various functionalities that exist in the various video services. Lastly, we discuss data allocation strategies which impact performance of interactive video on demand (IVOD). We present preliminary results from a study using a limited form of mirroring to support high performance IVOD. 相似文献
2.
Modeling the efficacy of persuasive strategies for different gamer types in serious games for health
Rita Orji Julita Vassileva Regan L. Mandryk 《User Modeling and User-Adapted Interaction》2014,24(5):453-498
Persuasive games for health are designed to alter human behavior or attitude using various Persuasive Technology (PT) strategies. Recent years have witnessed an increasing number of such games, which treat players as a monolithic group by adopting a one-size-fits-all design approach. Studies of gameplay motivation have shown that this is a bad approach because a motivational approach that works for one individual may actually demotivate behavior in others. In an attempt to resolve this weakness, we conducted a large-scale study on 1,108 gamers to examine the persuasiveness of ten PT strategies that are commonly employed in persuasive game design, and the receptiveness of seven gamer personalities (gamer types identified by BrianHex) to the ten PT strategies. We developed models showing the receptiveness of the gamer types to the PT strategies and created persuasive profiles, which are lists of strategies that can be employed to motivate behavior for each gamer type. We then explored the differences between the models and, based on the results, proposed two approaches for data-driven persuasive game design. The first is the one-size-fits-all approach that will motivate a majority of gamers, while not demotivating any player. The second is the personalized approach that will best persuade a particular type of gamer. We also compiled a list of the best and the worst strategies for each gamer type. Finally, to bridge the gap between game design and PT researchers, we map common game mechanics to the persuasive system design strategies. 相似文献
3.
Ifechukwu E. Adieze Justina C. Orji Rose N. Nwabueze G.O.C. Onyeze 《The International journal of environmental studies》2013,70(3):490-500
Responses to hydrocarbon stress of four tropical plants Panicum maximum, Zea mays, Centrosema sp. and Pueraria sp. grown in crude oil contaminated soils (1%, 5% and 10% w/w) were evaluated in a green house. Plants’ percentage survival, shoot heights, biomass development, and phytotoxicity susceptibility were used as indicators of growth, stress response and hydrocarbon tolerance. Relative to control, shoot heights and biomass of plants reduced with increasing hydrocarbon concentration, but 1% w/w oil-in-soil, stimulated shoot heights (5.9% and 6.4%) and weights (21.9% and 2.3%) in P. maximum and Centrosema sp. respectively. P. maximum tolerated the contaminant stress with biomass yields of 113% and 57% of control respectively in 1% and 10% w/w oil-in-soil. All the plants had 100% survival in 1% w/w, but considerably reduced survival in 10% w/w oil-in-soil. These results show that P. maximum has great potential for phytoremediation of petroleum contaminated soil. 相似文献
4.
As the number of video streams to be supported by a digital video delivery system (DVDS) increases, an improved understanding
of the necessity for reliable and cost-efficient support for a considerable number of video streams (in the magnitude of tens
of thousands), and the dependency largely on software capabilities emerges. Even in the presence of an optimal hardware configuration,
or model, and associated costs, using software to exploit the underlying hardware capabilities is of paramount importance.
Although a number of DVDSs have become operational, their ability to deliver the required services mainly depends on the small
number of streams supported and the hardware trade-offs. It is imperative that current software developments account for
the eventual scalability of the number of video streams without commensurate increase in hardware. In this paper, we present
strategies for the management of video streams in order to maintain and satisfy their space and time requirements. We use
a DVDS architectural model with functionally dichotomized nodes: a single-node partition is responsible for data retrieval,
while the remaining partition of nodes accepts user requests, determines object locations, and routes requests through the
network that connects both partitions. We present a detailed analysis of the issues related to queuing I/O requests and data
buffering. The discussion includes the requirements for arranging and scheduling I/O requests and data buffers, with the objective
of guaranteeing the required data availability rates for continuous media display. 相似文献
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Patrick F. Kiser Glenn C. Collupy Gary M. Eichenbaum Chad Rush Stephan Baumann Mark P.Kust Michael D. Greaves Erik D. Frederick Bernd Soltmann Helen Vasina Charles Orji Bruno Bienfiat John D. Brown John Davies Marquitta Atkins Jeffrey R. Lee Eric Labow Melissa Harp Ann F. Goodrich Hilton Conyers H. Mario Geysen 《Journal of The Association for Laboratory Automation》2001,6(6):99-106
The genomics revolution coupled to advances in computational power, informatics and robotics is driving drug discovery programs to produce drug candidates faster. This need has resulted in advances in high throughput methods for performing organic chemistry such as combinatorial and parallel synthesis. Yet there has not been a corollary advance in the ability to collect quantitative information on reactions that can be used to produce these drug candidates. This lack of an efficient and robust analytical method has resulted in a significant chemistry bottleneck. This work outlines a set of methods that helps address this chemistry bottleneck by using analytical constructs to detect and quantify reaction outcomes. To accomplish this, an integrated experimentalcheminformatics platform has been developed which couples an experimental design system, automated high throughput parallel and combinatorial synthesis methodology, sample processing, quantitative mass spectroscopy and automated data analysis. This platform is being used to optimize single reactions and the syntheses of whole libraries of compounds, and to generate large databases on specific reaction classes. 相似文献
7.
Eating out has recently become part of our lifestyle. However, when eating out in restaurants, many people find it difficult to make meal choices consistent with their health goals. Bad eating choices and habits are in part responsible for the alarming increase in the prevalence of chronic diseases such as obesity, diabetes, and high blood pressure, which burden the health care system. Therefore, there is a need for an intervention that educates the public on how to make healthy choices while eating away from home. In this paper, we propose a goal-based slow-casual game approach that addresses this need. This approach acknowledges different groups of users with varying health goals and adopts slow technology to promote learning and reflection. We model two recognized determinants of well-being into dietary interventions and provide feedback accordingly. To demonstrate the suitability of our approach for long-term sustained learning, reflection, and attitude and/or behavior change, we develop and evaluate LunchTime—a goal-based slow-casual game that educates players on how to make healthier meal choices. The result from the evaluation shows that LunchTime facilitates learning and reflection and promotes positive dietary attitude change. 相似文献
8.
Local red and white, and SK5912 varieties of sorghum grains were malted, and assayed for amylase, diastatic and lipase activities. The 5‐day malts from the red and white varieties were fermented for 48 h to produce burukutu, during which, lipase activities were monitored. Malt values peaked on day 5, and the red malts had the highest diastatic activities while the white variety had the lowest. Lipase activity in the malts peaked on day 4 with the red having the highest activity. The pH of the fermenting gruels decreased from 5.33 and 5.35 and levelled off at 3.88 and 3.85 for the red and white malts respectively. During fermentation, lipase activity peaks were detected at 0 h, 21 h and 45 h for the red malt with the highest peak at 45 h. The peak fermentation times for lipase activity in the white malt was at 0 h, 21 h and 48 h with the highest peak at 48 h. Lipase activity within the first 39 h was higher in the white gruel. Sorghum malt lipase from the red and white varieties may consist of three isoforms, two of which may have activity optima in the acidic pH range. 相似文献
9.
Video partitioning is the segmentation of a videosequence into visually independent partitions,which represent various identifiable scenes in thevideo. It is an important first step inconsidering other issues in video databasesmanagement, such as indexing and retrieval. Asvideo partitioning is a computationally intensiveprocess, effective management of digital videorequires highly efficient techniques for theprocess. In general, for compressed anduncompressed video, the basic mechanism used toreduce computation is by selective processing of asubpart of the video frames. However, so farthe choice of this proportion has been maderandomly, without any formal basis. An ad hocselection of this subpart cannot always guaranteea reduction in computation while ensuringeffective partitioning.This paper presents formal methods for determiningthe optimal window size and the minimum thresholdswhich ensure that decisions on scene similarityare made on a reliable, effective and principledbasis. Further, we propose the use ofneighbourhood-based colour ratios, and derive theratio feature for both uncompressed and transformcoded video. The neighbourhood-based ratiofeatures account for both illumination variationand possible motion in the video, while avoidingthe computational burden of explicit motioncompensation procedures. Empirical results showing the performance of the proposed techniques are are also presented. 相似文献
10.