Towards a Small-Scale Model for Ubiquitous Learning

Technology Platform Innovations and Forthcoming Trends in Ubiquitous Learning - Advances in Educational Technologies and Instructional Design ◽

10.4018/978-1-4666-4542-4.ch004 ◽

2014 ◽

pp. 60-76

Author(s):

Jorge Luis Victória Barbosa ◽

Débora Nice Ferrari Barbosa

Keyword(s):

Large Scale ◽

Scale Model ◽

Small Scale ◽

Context Aware ◽

Ubiquitous Learning ◽

Learning Spaces ◽

Context Aware Computing ◽

Real Scenario ◽

Initial Results ◽

Small Scale Model

The ever-increasing use of mobile devices allied to the widespread adoption of wireless network technology has greatly stimulated mobile and ubiquitous computing research. The adoption of mobile technology enables improvement to several application areas, such as education. New pedagogical opportunities can be created through the use of location systems and context-aware computing technology to track each learner's location and customize his/her learning process. In this chapter, the authors discuss a ubiquitous learning model called LOCAL (Location and Context Aware Learning). LOCAL was created to explore those aforementioned pedagogical opportunities, leveraging location technology and context management in order to support ubiquitous learning and facilitate collaboration among learners. This model was conceived for small-scale learning spaces, but can be extended in order to be applied to a large-scale environment. Initial results were obtained in a real scenario, attesting the viability of the approach.

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Fracture Strength Estimation of SiC Block for IS Process

18th International Conference on Nuclear Engineering: Volume 3 ◽

10.1115/icone18-29267 ◽

2010 ◽

Author(s):

Hiroaki Takegami ◽

Atsuhiko Terada ◽

Kaoru Onuki ◽

Ryutaro Hino

Keyword(s):

Fracture Strength ◽

Large Scale ◽

Weibull Modulus ◽

Reliability Assessment ◽

Prediction Method ◽

Scale Model ◽

Small Scale ◽

Energy Agency ◽

Destructive Test ◽

Small Scale Model

The Japan Atomic Energy Agency has been conducting R&D on thermochemical water-splitting Iodine-Sulfur (IS) process for hydrogen production to meet massive demand in the future hydrogen economy. A concept of sulfuric acid decomposer was developed featuring a heat exchanger block made of SiC. Recent activity has focused on the reliability assessment of SiC block. Although knowing the strength of SiC block is important for the reliability assessment, it is difficult to evaluate a large-scale ceramics structure without destructive test. In this study, a novel approach for strength estimation of SiC structure was proposed. Since accurate strength estimation of individual ceramics structure is difficult, a prediction method of minimum strength in the structure of the same design was proposed based on effective volume theory and optimized Weibull modulus. Optimum value of the Weibull modulus was determined for estimating the lowest strength. The strength estimation line was developed by using the determined modulus. The validity of the line was verified by destructive test of SiC block model, which is small-scale model of the SiC block. The fracture strength of small-scale model satisfied the predicted strength.

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Non-Repeatability, Scale- and Model Effects in Laboratory Measurement of Impact Loads Induced by an Overtopped Bore on a Dike Mounted Wall

Volume 3: Structures, Safety, and Reliability ◽

10.1115/omae2019-96703 ◽

2019 ◽

Author(s):

Maximilian Streicher ◽

Andreas Kortenhaus ◽

Corrado Altomare ◽

Steven Hughes ◽

Krasimir Marinov ◽

...

Keyword(s):

Large Scale ◽

Scale Effects ◽

Vertical Wall ◽

Scale Factor ◽

Scale Model ◽

Small Scale ◽

Length Scale ◽

Force Measurements ◽

Impact Forces ◽

Small Scale Model

Abstract Overtopping bore impact forces on a dike mounted vertical wall were measured in similar large-scale (Froude length scale factor 1-to-4.3) and small-scale (Froude length scale factor 1-to-25) models. The differences due to scale effects were studied, by comparing the up-scaled force measurements from both models in prototype. It was noted that if a minimum layer thickness, velocity of the overtopping flow and water depth at the dike toe were maintained in the small-scale model, the resulting differences in impact force due to scale effects are within the range of differences due to non-repeatability and model effects.

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New Efficient Sparse Space–Time Algorithms for Superparameterization on Mesoscales

Monthly Weather Review ◽

10.1175/2009mwr2858.1 ◽

2009 ◽

Vol 137 (12) ◽

pp. 4307-4324 ◽

Cited By ~ 30

Author(s):

Yulong Xing ◽

Andrew J. Majda ◽

Wojciech W. Grabowski

Keyword(s):

Large Scale ◽

Space Time ◽

Horizontal Velocity ◽

Specific Humidity ◽

Scale Model ◽

Small Scale ◽

Squall Lines ◽

Scale Models ◽

New Algorithms ◽

Small Scale Model

Abstract Superparameterization (SP) is a large-scale modeling system with explicit representation of small-scale and mesoscale processes provided by a cloud-resolving model (CRM) embedded in each column of a large-scale model. New efficient sparse space–time algorithms based on the original idea of SP are presented. The large-scale dynamics are unchanged, but the small-scale model is solved in a reduced spatially periodic domain to save the computation cost following a similar idea applied by one of the authors for aquaplanet simulations. In addition, the time interval of integration of the small-scale model is reduced systematically for the same purpose, which results in a different coupling mechanism between the small- and large-scale models. The new algorithms have been applied to a stringent two-dimensional test suite involving moist convection interacting with shear with regimes ranging from strong free and forced squall lines to dying scattered convection as the shear strength varies. The numerical results are compared with the CRM and original SP. It is shown here that for all of the regimes of propagation and dying scattered convection, the large-scale variables such as horizontal velocity and specific humidity are captured in a statistically accurate way (pattern correlations above 0.75) based on space–time reduction of the small-scale models by a factor of ⅓; thus, the new efficient algorithms for SP result in a gain of roughly a factor of 10 in efficiency while retaining a statistical accuracy on the large-scale variables. Even the models with ⅙ reduction in space–time with a gain of 36 in efficiency are able to distinguish between propagating squall lines and dying scattered convection with a pattern correlation above 0.6 for horizontal velocity and specific humidity. These encouraging results suggest the possibility of using these efficient new algorithms for limited-area mesoscale ensemble forecasting.

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Study on Multi-Scale Coupled Ecological Dispatching Model Based on the Decomposition-Coordination Principle

Water ◽

10.3390/w11071443 ◽

2019 ◽

Vol 11 (7) ◽

pp. 1443

Author(s):

Zhou ◽

Dong ◽

Wang ◽

Shi ◽

Gao ◽

...

Keyword(s):

Large Scale ◽

Scale Model ◽

Small Scale ◽

Adaptive Genetic Algorithm ◽

Hydrologic Alteration ◽

Multi Scale ◽

Large Scale Model ◽

Calculation Results ◽

Coordination Principle ◽

Small Scale Model

Studies on environmental flow have developed into a flow management strategy that includes flow magnitude, duration, frequency, and timing from a flat line minimum flow requirement. Furthermore, it has been suggested that the degree of hydrologic alteration be employed as an evaluation method of river ecological health. However, few studies have used it as an objective function of the deterministic reservoir optimal dispatching model. In this work, a multi-scale coupled ecological dispatching model was built, based on the decomposition-coordination principle, and considers multi-scale features of ecological water demand. It is composed of both small-scale model and large-scale model components. The small-scale model uses a daily scale and is formulated to minimize the degree of hydrologic alteration. The large-scale model uses a monthly scale and is formulated to minimize the uneven distribution of water resources. In order to avoid dimensionality, the decomposition coordination algorithm is utilized for the coordination among subsystems; and the adaptive genetic algorithm (AGA) is utilized for the solution of subsystems. The entire model—which is in effect a large, complex system—was divided into several subsystems by time and space. The subsystems, which include large-scale and small-scale subsystems, were correlated by coordinating variables. The lower reaches of the Yellow River were selected as the study area. The calculation results show that the degree of hydrologic alteration of small-scale ecological flow regimes and the daily stream flow can be obtained by the model. Furthermore, the model demonstrates the impact of considering the degree of hydrologic alteration on the reliability of water supply. Thus, we conclude that the operation rules extracted from the calculation results of the model contain more serviceable information than that provided by other models thus far. However, model optimization results were compared with results from the POF approach and current scheduling. The comparison shows that further reduction in hydrologic alteration is possible and there are still inherent limitations within the model that need to be resolved.

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Hydro-Mechanical Modeling of the Year 2000 Hydraulic Stimulation of GPK2 Well, Soultz-sous-Forêts, France

10.5194/egusphere-egu21-15088 ◽

2021 ◽

Author(s):

Dariush Javani ◽

Jean Schmittbuhl ◽

Francois Cornet

Keyword(s):

Mechanical Behavior ◽

Large Scale ◽

Fracture Network ◽

P Wave ◽

Scale Model ◽

Small Scale ◽

Hydraulic Stimulation ◽

Year 2000 ◽

Small Scale Model ◽

Stimulation Of

&#160;Hydraulic stimulation of pre-existing fractures and faults plays a significant role in improving hydraulic conductivity of the fracture network around injection and production wells in geothermal reservoirs. It is therefore important to characterize the hydro-mechanical behavior of the faults against fluid injection. The Soultz-sous-For&#234;ts site (France) has been an EGS pilot site where several major hydraulic stimulations have been performed and are well documented (https://cdgp.u-strasbg.fr/ and https://tcs.ah-epos.eu/).Here we use the 3DEC numerical modeling tool (Itasca) to analyze the year 2000 stimulation of GPK2 well where large scale seismic anomalies have been evidenced during the different stages of the stimulation using 4D-P-wave tomography (Calo et al, 2011). The specificity of the approach is to combine two modeling at different scales. First, a small-scale model (100x100x100 m3) is built to analyze the effective mechanical response of a stochastic discrete fracture network (DFN) following the statistical features of the observed fracture network (Massart et al, 2010). Second, a large-scale numerical model of the Soultz-sous-For&#234;ts reservoir (5000x5000x5000 m3) containing the largest faults of the reservoir defined by Sausse et al., 2010, is developed including regional stresses. The objective is to constrain the large-scale mechanical properties of the surrounding matrix around the fault from the small-scale model, in particular, its hydro-mechanical behavior in terms of non-linear elastic response related to the stochastic DFN. As a first step only the largest fault (GPK3-FZ4770) is considered. The first stage of the stimulation is modelled as a constant flow rate of 30 ls-1 of water injected into the fault at the depth of approximately 4.7 km. We explored the effect of the normal and shear stiffness of the fault on the dynamical response of pore pressure along the fracture and the onset of slip. It is found that the increase of the aperture of the fault during the injection shows a slow migration (~2 cm/s) owing to poro-elastic effects. Also generated fluid pressure throughout the fault shows a long period oscillating behavior (~5 hr) sensitive to the magnitude of the fracture normal stiffness.

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STUDY OF POSITIVE PRESSURE VENTILATION IN ROOM FIRES USING A SMALL-SCALE MODEL

Heat Transfer Research ◽

10.1615/heattransres.2018025564 ◽

2019 ◽

Vol 50 (3) ◽

pp. 243-261

Author(s):

T. Y. Yeung ◽

W. K. Chow

Keyword(s):

Positive Pressure Ventilation ◽

Scale Model ◽

Positive Pressure ◽

Small Scale ◽

Room Fires ◽

Small Scale Model

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RANCANG BANGUN PERANGKAT EKSPERIMENTASI PROSES PIROLISIS BIOMASA GELOMBANG MIKRO

Jurnal Sains dan Teknologi Indonesia ◽

10.29122/jsti.v14i2.920 ◽

2013 ◽

Vol 14 (2) ◽

Author(s):

Noor Fachrizal

Keyword(s):

Large Scale ◽

Continuous Model ◽

Biomass Energy ◽

Scale Model ◽

Small Scale ◽

Laboratory Apparatus ◽

Liquid Form ◽

Large Scale Model ◽

Bio Oil ◽

Pyrolysis Of Biomass

Biomass such as agriculture waste and urban waste are enormous potency as energy resources instead of enviromental problem. organic waste can be converted into energy in the form of liquid fuel, solid, and syngas by using of pyrolysis technique. Pyrolysis process can yield higher liquid form when the process can be drifted into fast and flash response. It can be solved by using microwave heating method. This research is started from developing an experimentation laboratory apparatus of microwave-assisted pyrolysis of biomass energy conversion system, and conducting preliminary experiments for gaining the proof that this method can be established for driving the process properly and safely. Modifying commercial oven into laboratory apparatus has been done, it works safely, and initial experiments have been carried out, process yields bio-oil and charcoal shortly, several parameters are achieved. Some further experiments are still needed for more detail parameters. Theresults may be used to design small-scale continuous model of productionsystem, which then can be developed into large-scale model that applicable for comercial use.

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Wave Energy Hyperbaric Device for Electricity Production

Volume 5: Ocean Space Utilization; Polar and Arctic Sciences and Technology; The Robert Dean Symposium on Coastal and Ocean Engineering; Special Symposium on Offshore Renewable Energy ◽

10.1115/omae2007-29743 ◽

2007 ◽

Cited By ~ 7

Author(s):

Segen F. Estefen ◽

Paulo Roberto da Costa ◽

Eliab Ricarte ◽

Marcelo M. Pinheiro

Keyword(s):

Power Generation ◽

Wave Energy ◽

Experimental Results ◽

Electricity Production ◽

Scale Model ◽

Small Scale ◽

Regular Waves ◽

Hyperbaric Chamber ◽

Small Scale Model

Wave energy is a renewable and non-polluting source and its use is being studied in different countries. The paper presents an overview on the harnessing of energy from waves and the activities associated with setting up a plant for extracting energy from waves in Port of Pecem, on the coast of Ceara State, Brazil. The technology employed is based on storing water under pressure in a hyperbaric chamber, from which a controlled jet of water drives a standard turbine. The wave resource at the proposed location is presented in terms of statistics data obtained from previous monitoring. The device components are described and small scale model tested under regular waves representatives of the installation region. Based on the experimental results values of prescribed pressures are identified in order to optimize the power generation.

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