Multimedia Model Research Articles

Evaluation of mercury concentration in the lake biwa-yodo river basin by a one-box multimedia model and model sensitivity on the experimentally determined water-sediment partition coefficient

Abstract Considering the environmental damage caused by mercury, evaluating mercury concentrations in four environmental media, namely the atmosphere, water, soil, and sediment, is necessary. Available data on mercury emissions and

Health Risk from Exposure to PCDD/Fs from a Waelz Plant in Central Taiwan

This study combined ambient air sampling and biomonitoring data to determine the PCDD/Fs exposure levels and health risk for residents near a Waelz plant. In total, 457 adults completed questionnaires and 48 subjects also gave blood samples. We used the USEPA multimedia model to estimate lifetime exposure and cancer risk. Analytical results show that average atmospheric PCDD/Fs concentrations were 149–285 fg I-TEQ/m 3 and deposition flux was 0.57–116 pg I-TEQ/m 2 -d.

An enhanced environmental multimedia modeling system based on fuzzy-set approach: I. theoretical framework and model development

Multimedia environmental modeling is extremely complex due to the intricacy of the systems with the consideration of many related factors. Traditional environmental multimedia models (EMMs) are usually based on one-dimensional and first-order assumptions, which may cause numerical errors in the simulation results. In this study, a new user-friendly fuzzy-set enhanced environmental multimedia modeling system (FEEMMS) is developed, and includes four key modules: an air dispersion module, a polluting source module, an unsaturated zone module, and a groundwater module. Many improvements over previous EMMs have been achieved through dynamically quantifying the intermedia mass flux; incorporating fuzzy-set approach into environmental multimedia modeling system (EMMS); and designing a user-friendly graphic user interface (GUI). The developed FEEMMS can be a useful tool in estimating the time-varying and spatial-varying chemical concentrations in air, soil, and groundwater; characterizing the potential risk to human health presented by contaminants released from a contaminated site; and quantifying the uncertainties associated with modeling systems and subsequently providing robustness and flexibility for the remediation-related decision making.

A multi-media planning model for assessing co-located energy and desalination plants

The co-location of desalination plants with existing or proposed power plants can bring forth economic and ecological advantages in terms of reducing the costs of water intake and reducing fish impingement. However, fossil fuel-based power plants are a source of ozone precursors and the added strain of power needed for the energy intensive desalination process increases these pollutants into the atmosphere. Furthermore, withdrawal from brackish water sources puts a stress on slowly replenishing aquifers. Additionally, the resulting concentrate is highly saline and disposal into ecologically sensitive bays and estuaries may be problematic. Balancing these limitations with the need for freshwater is of great importance for sustainability of water scarce arid and semi-arid regions and also requires a holistic multimedia impact evaluation. Therefore, an integrated system of systems approach is adopted in this study and a decision support system that integrates the flow of water, concentrate and resulting pollutants through two engineered (power plant and desalination plant) as well as three natural systems (coastal bay, aquifer and the atmosphere) is developed to study the co-location of a power plant and a desalination plant near the City of Corpus Christi in South Texas. The objective of the model is to minimize the amount of groundwater extraction and minimize the amount of water extracted from the bay to emphasize water and ecosystem conservation, respectively. These objectives, in turn, are subject to various other constraints including (1) conservation of mass; (2) air quality regulations; (3) salinity regulation policies; (4) groundwater management constraints; (5) water demand requirements; and (6) energy demand constraints. The results indicate that when conservation of the aquifer is weighted more, less water is pulled from the aquifer until later time periods. The salinity of the bay increases and creates a need for a greater amount of power necessary to process the saline water which, in turn, enhances the atmospheric loading of ozone precursors. Therefore, the conservation of groundwater scenario is limited by the air quality standards. Alternatively, when the goal is to conserve the ecological integrity of the bay while meeting freshwater demands, the model is bound by the prescribed drawdown constraint that limits the amount of water that can be extracted from the aquifer. The results from the study indicate that blending saline bay water with brackish groundwater and using cleaner burning fossil fuels that have limited air quality impacts will enhance the performance of the co-located power and desalination operations. The results of the study highlight the need for an integrated multimedia evaluation in assessing the feasibility of desalination in areas with marginal air quality.

Using gridded multimedia model to simulate spatial fate of Benzo[α]pyrene on regional scale

Predicting the environmental multimedia fate is an essential step in the process of assessing the human exposure and health impacts of chemicals released into the environment. Multimedia fate models have been widely applied to calculate the fate and distribution of chemicals in the environment, which can serve as input to a human exposure model. In this study, a grid based multimedia fugacity model at regional scale was developed together with a case study modeling the fate and transfer of Benzo[α]pyrene (BaP) in Bohai coastal region, China. Based on the estimated emission and in-site survey in 2008, the BaP concentrations in air, vegetation, soil, fresh water, fresh water sediment and coastal water as well as the transfer fluxes were derived under the steady-state assumption. The model results were validated through comparison between the measured and modeled concentrations of BaP. The model results indicated that the predicted concentrations of BaP in air, fresh water, soil and sediment generally agreed with field observations. Model predictions suggest that soil was the dominant sink of BaP in terrestrial systems. Flow from air to soil, vegetation and costal water were three major pathways of BaP inter-media transport processes. Most of the BaP entering the sea was transferred by air flow, which was also the crucial driving force in the spatial distribution processes of BaP. The Yellow River, Liaohe River and Daliao River played an important role in the spatial transformation processes of BaP. Compared with advection outflow, degradation was more important in removal processes of BaP. Sensitivities of the model estimates to input parameters were tested. The result showed that emission rates, compartment dimensions, transport velocity and degradation rates of BaP were the most influential parameters for the model output. Monte Carlo simulation was carried out to determine parameter uncertainty, from which the coefficients of variation for the estimated BaP concentrations in air and soil were computed, which were 0.46 and 1.53, respectively. The model output–concentrations of BaP in multimedia environment can be used in human exposure and risk assessment in the Bohai coastal region. The results also provide significant indicators on the likely dominant fate, influence range of emission and transport processes determining behavior of BaP in the Bohai coastal region, which is instrumental in human exposure and risk assessment in the region.

Attention, Working Memory, and Long-Term Memory in Multimedia Learning: An Integrated Perspective Based on Process Models of Working Memory

Cognitive models of multimedia learning such as the Cognitive Theory of Multimedia Learning (Mayer 2009) or the Cognitive Load Theory (Sweller 1999) are based on different cognitive models of working memory (e.g., Baddeley 1986) and long-term memory. The current paper describes a working memory model that has recently gained popularity in basic research: the embedded-processes model (Cowan 1999). The embedded-processes model argues that working memory is not a separate cognitive system but is the activated part of long-term memory. A subset of activated long-term memory is assumed to be particularly highlighted and is termed the “focus of attention.” This model thus integrates working memory, long-term memory, and (voluntary and involuntary) attention, and referring to it within multimedia models provides the opportunity to model all these learning-relevant cognitive processes and systems in a unitary way. We make suggestions for incorporating this model into theories of multimedia learning. On this basis, one cannot only reinterpret crucial phenomena in multimedia learning that are attributed to working memory (the split-attention effect, the modality effect, the coherence effect, the signaling effect, the redundancy effect, and the expertise reversal effect) but also derive new predictions.

Model predictions of toxaphene degradation in the atmosphere over North America

Technical toxaphene, a broad-spectrum pesticide mixture, degrades in the environment, resulting in potential changes in toxicity. The present study uses a multimedia model that the authors developed to estimate toxaphene degradation in the atmosphere over North America. The predicted degradation has strong spatial and temporal variability determined by processes such as emission and transport of technical toxaphene, as well as the complex interactions among many species (e.g., toxaphene, hydroxyl [OH] radicals, and ozone). More toxaphene is degraded in warmer months due to higher concentrations of technical toxaphene (primarily due to higher technical toxaphene emissions in the southeastern United States and transport to other regions) and OH radicals. In the model, OH radicals are created primarily through the reactions of water vapor with the excited oxygen atom, O(¹D), generated by the photolysis of ozone, which is produced primarily by reactions of volatile organic compounds and nitrogen oxides (NOx) in the presence of sunlight. The higher OH concentrations in warmer months are primarily the result of higher solar radiation and ozone concentrations. The spatial distribution of degradation depends on the distribution of technical toxaphene soil residues as well as atmospheric transport and chemistry; significant chemical degradation occurs in the southeastern United States where soils are most heavily contaminated by past applications of toxaphene.

Storytelling and Videogames. An interdisciplinary appro- ach to interactive multimedia models for children

Although scientific literature, since long time, underlines the importance of storytelling and games as essential cognitive and educational moments, current studies and researches are largely resting over a separate analysis of games and storytelling, establishing a hierarchy among them which crowns one or the other likewise from time to time. It is therefore necessary developing and tuning up methods and educational model that will allow us to develop the natural attitude of human mind to place all information inside one context and one set.

Low-level and high-level prior learning for visual saliency estimation

Visual saliency estimation is an important issue in multimedia modeling and computer vision, and constitutes a research field that has been studied for decades. Many approaches have been proposed to solve this problem. In this study, we consider the visual attention problem blue with respect to two aspects: low-level prior learning and high-level prior learning. On the one hand, inspired by the concept of chance of happening, the low-level priors, i.e., Color Statistics-based Priors (CSP) and Spatial Correlation-based Priors (SCP), are learned to describe the color distribution and contrast distribution in natural images. On the other hand, the high-level priors, i.e., the relative relationships between objects, are learned to describe the conditional priority between different objects in the images. In particular, we first learn the low-level priors that are statistically based on a large set of natural images. Then, the high-level priors are learned to construct a conditional probability matrix blue that reflects the relative relationship between different objects. Subsequently, a saliency model is presented by integrating the low-level priors, the high-level priors and the Center Bias Prior (CBP), in which the weights that correspond to the low-level priors and the high-level priors are learned based on the eye tracking data set. The experimental results demonstrate that our approach outperforms the existing techniques.

Climate-based archetypes for the environmental fate assessment of chemicals

Emissions of chemicals have been on the rise for years, and their impacts are greatly influenced by spatial differentiation. Chemicals are usually emitted locally but their impact can be felt both locally and globally, due to their chemical properties and persistence. The variability of environmental parameters in the emission compartment may affect the chemicals' fate and the exposure at different orders of magnitude. The assessment of the environmental fate of chemicals and the inherent spatial differentiation requires the use of multimedia models at various levels of complexity (from a simple box model to complex computational and high-spatial-resolution models). The objective of these models is to support ecological and human health risk assessment, by reducing the uncertainty of chemical impact assessments. The parameterisation of spatially resolved multimedia models is usually based on scenarios of evaluative environments, or on geographical resolutions related to administrative boundaries (e.g. countries/continents) or landscape areas (e.g. watersheds, eco-regions). The choice of the most appropriate scale and scenario is important from a management perspective, as a balance should be reached between a simplified approach and computationally intensive multimedia models. In this paper, which aims to go beyond the more traditional approach based on scale/resolution (cell, country, and basin), we propose and assess climate-based archetypes for the impact assessment of chemicals released in air. We define the archetypes based on the main drivers of spatial variability, which we systematically identify by adopting global sensitivity analysis techniques. A case study that uses the high resolution multimedia model MAPPE (Multimedia Assessment of Pollutant Pathways in the Environment) is presented. Results of the analysis showed that suitable archetypes should be both climate- and chemical-specific, as different chemicals (or groups of them) have different traits that influence their spatial variability. This hypothesis was tested by comparing the variability of the output of MAPPE for four different climatic zones on four different continents for four different chemicals (which represent different combinations of physical and chemical properties). Results showed the high suitability of climate-based archetypes in assessing the impacts of chemicals released in air. However, further research work is still necessary to test these findings.

Assessment of climate change impact on the fates of polycyclic aromatic hydrocarbons in the multimedia environment based on model prediction

The objective was to quantitatively understand the impacts of climate change (CC) under the A1B scenario on the contamination levels of 11 polycyclic aromatic hydrocarbons (PAHs) from pyrogenic sources in the environmental media based on model prediction. To predict the impacts of CC in South Korea, a revised version of KoEFT-PBTs, a dynamic multimedia model for persistent organic pollutants in South Korea, was used. Simulations were conducted for the period from 2000 to 2049 under the A1B scenario with the emission data for 2009 and the results for Seoul and Kangwon were compared to those under no climate change (NCC) scenario. Due to CC, the average of annual or monthly average concentration changes within a factor of two for the PAHs in air, soil and water. Time dependent comparison indicates that the maximum increase induced by CC in the monthly average concentration ranges from 10 to 102 in air and water. Change in advective flux due to wind speed difference between A1B and NCC dictates the change of the atmospheric PAHs levels while wet particle deposition due to rain rate difference contributes to some extent to the change of 5 and 6 ring PAHs. Whether the concentration change is positive or not depends primarily on the emission strength of internal sources relative to those in surrounding areas. The CC induced changes in atmospheric depositions and degradation rate in soil play a leading role in the change of soil concentration. In water, runoff and degradation are the key processes to the CC induced concentration change. Both in soil and water, the relative importance of individual key processes varies with PAHs. The difference between the two scenarios in wind speed and in rain rate shows stronger correlations with the concentration change than the temperature change.

Architecting Multimedia Content Publish/Subscribe Applications: A Graph-Oriented Approach

This paper presents an approach, called GOM, for modeling and implementing the architecture of multimedia content publish/subscribe (Pub/Sub) applications using a graph-oriented multimedia (GOM) model. The GOM unites three of the applications aspects, namely the content aspect, the semantic aspect, and the functional aspect, and provides means for the integration of ontological knowledge within the GOM graph structure. A formal definition is proposed for the GOM. Performance is evaluated. The results show that the GOM can easily be constructed, while enabling an efficient management by the publishing and subscribing of multimedia content.

EFFECTS OF INQUIRY TRAINING LEARNING MODEL BASED MULTIMEDIA AND MOTIVATION OF PHYSICS STUDENT LEARNING OUTCOMES

The objective in this research: (1) Determine a better learning model to improve learning outcomes physics students among learning model Inquiry Training based multimedia and Inquiry Training learning model. (2) Determine the level of motivation to learn in affects physics student learning outcomes. (3) Knowing the interactions between the model of learning and motivation in influencing student learning outcomes. This research is a quasi experimental. The population in this research was all students in class XI SMA Negeri 1 T.P Sunggal Semester I 2012/2013. The sample of this research was consisted of two classes with a sample of 70 peoples who are determined by purposive sampling, the IPA XI-2 as a class experiment using a model-based multimedia learning Training Inquiry as many as 35 peoples and XI IPA-3 as a control class using learning model Inquiry Training 35 peoples. Hypotheses were analyzed using the GLM at significant level of 0.05 using SPSS 17.0 for Windows. Based on data analysis and hypothesis testing conducted found that: (1) Training Inquiry-based multimedia learning model in improving student learning outcomes rather than learning model physics Inquiry Training. (2) The results of studying physics students who have high motivation to learn better than students who have a low learning motivation. (3) From this research there was an interaction between learning model inquiry-based multimedia training and motivation to study on learning outcomes of students.

Literary History in Transnational Mode: The Challenges of Writing a History of East-Central European Literatures

As Priscilla Wald notes in her comments on A New Literary History of America, edited by Greil Marcus and Werner Sollors (2009), “Literary history is not at all a dead activity. Genres, like disciplines, are dynamic, as is the concept of the literary.” As she explains further, the guiding principle of A New Literary History of America is prismatic, assembling various disciplinary perspectives and offering a “carnival of style, voice, and topic.” The various chapters in it “function as individual vignettes, moments in time that readily form connections to other vignettes and help the reader see constellations among eras.”1 The prismatic, multicultural, and to some extent multimedia model of literary history that Wald describes has been applied in a few recent histories, including A Comparative History of Literatures in the Iberian Peninsula, edited by Fernando Cabo Aseguinolaza, Anxo Abuin Gonzalez, and Cesar Dominguez, and History of the Literary Cultures of East-Central Europe which I coedited with John Neubauer.2 The latter work, published in four volumes between 2004 and 2010, attempts a comprehensive transnational study of the cultural and literary region that stretches from the Baltic countries to Bulgaria and Albania and from Ukraine and Moldova in the east to the Czech Republic in the west. Representing the joint work of more than 120 contributors from Europe, the United States, Canada, and Australia, this project, sponsored by the International Comparative Literature Association, is not a chronological narrative, but an experiment in writing literary history that acknowledges ruptures as well as transnational connections. Hence the project’s subtitle: Conjunctures and Disjunctures in the 19th and 20th Centuries.

Evaluation of lead concentration by one-box type multimedia model in Lake Biwa-Yodo River basin of Japan

A one box type multimedia model was developed and applied for Lake Biwa-Yodo River basin in Japan to assess the distribution of lead in the environment. This model is based on mass balance and includes four environmental media; the atmosphere, the soil, the water body, and the sediment. The mass balance of lead is represented by the summation of mass transfer flux at equilibrium, emission flux, advection flux, and deposition flux or sedimentation flux. In the case of metallic compounds, dissolution rate and exchange equilibrium have also been taken into consideration. Pollutant Release and Transfer Registry (PRTR) in Japan was used as one of the major data source for this study. The emission of lead in Lake Biwa-Yodo River basin is calculated based on five sources of registered emission in PRTR, unregistered emission in PRTR, incinerators, leaded gasoline, and landfills. In this study, we estimated lead emission from 1957 to 2007 to observe the temporal accumulation of lead. Calculated lead concentrations were compared with the measured/observed concentrations. It was found out that the model could closely predict lead concentration in the soil and the water body. The concentration in the atmosphere was underestimated by the calculated concentrations. The reason was attributed to the underestimation of the amount of lead emission from incinerators.

Evaluating the fate and behaviour of cyclic volatile methyl siloxanes in two contrasting North American lakes using a multi-media model

The behaviour of cyclic volatile methyl siloxanes (cVMS) in lakes was explored using a fugacity-based steady-state non-equilibrium multimedia fate and transport model (a modified version of QWASI). Three substances were investigated: Octamethylcyclotetrasiloxane (D4), Decamethylcyclopentasiloxane (D5) and Dodecamethylcyclohexasiloxane (D6) in two contrasting North American lakes: Lake Ontario and Lake Pepin (a natural shallow lake on the Mississippi river between Minnesota and Wisconsin). Values for the principal partition coefficients and the hydrolysis rate constant were adjusted for the mean annual temperatures of each lake. Hydrolysis rate constants were also adjusted for the fraction of chemical calculated to be in the freely dissolved phase. Half-lives in sediment were calculated from partitioning theory, assuming hydrolysis can occur only in the dissolved phase. Best estimates of substance-specific emissions were obtained by combining current per capita approximations of usage and fraction lost to domestic waste water, the population of the lake catchment and cVMS removal in waste water treatment. Concentrations were generally lower and chemical residence times longer in Lake Ontario than in Lake Pepin, owing to greater depth, a higher hydraulic retention time and a higher degree of dilution. Overall persistence in Lake Pepin is significantly influenced by the high rate of sediment burial assumed in the model, as well as by a relatively high rate of water discharge. Despite the many similarities of the compounds considered, the dominant loss mechanisms vary significantly and are not the same in each lake system. This highlights the pitfalls of subjective evaluation of chemical fate and illustrates the important role which models have to play in providing a quantitative framework for assessing chemical behaviour objectively under the influence of a complex and interacting set of factors.

When spatial and temporal contiguities help the integration in working memory: “A multimedia learning” approach

Two experiments examined the effects of spatial and temporal contiguities in a working memory binding task that required participants to remember coloured objects. In Experiment 1, a black and white drawing and a corresponding phrase that indicated its colour perceptually were either near or far (spatial study condition), while in Experiment 2, the colour phrase and the black and white drawing were presented either simultaneously or sequentially (temporal study condition). Results showed that the absence of contiguity negatively affected binding performance. Data is discussed in line with theoretical and multimedia models of integrative processes in working memory.

Persistent Organic Pollutants in Fresh Water Ecosystems

Persistent Organic Pollutants in Fresh Water Ecosystems

Evaluating the environmental fate of short-chain chlorinated paraffins (SCCPs) in the Nordic environment using a dynamic multimedia model

Short chain chlorinated paraffins (SCCPs) raise concerns due to their potential for persistence, bioaccumulation, long-range transport and adverse effects. An understanding of their environmental fate remains limited, partly due to the complexity of the mixture. The purpose of this study was to evaluate whether a mechanistic, integrated, dynamic environmental fate and bioaccumulation multimedia model (CoZMoMAN) can reconcile what is known about environmental emissions and human exposure of SCCPs in the Nordic environment. Realistic SCCP emission scenarios, resolved by formula group, were estimated and used to predict the composition and concentrations of SCCPs in the environment and the human food chain. Emissions at the upper end of the estimated range resulted in predicted total concentrations that were often within a factor of 6 of observations. Similar model performance for a complex group of organic contaminants as for the well-known polychlorinated biphenyls strengthens the confidence in the CoZMoMAN model and implies a relatively good mechanistic understanding of the environmental fate of SCCPs. However, the degree of chlorination predicted for SCCPs in sediments, fish, and humans was higher than observed and poorly established environmental half-lives and biotransformation rate constants contributed to the uncertainties in the predicted composition and ∑SCCP concentrations. Improving prediction of the SCCP composition will also require better constrained estimates of the composition of SCCP emissions. There is, however, also large uncertainty and lack of coherence in the existing observations, and better model-measurement agreement will require improved analytical methods and more strategic sampling. More measurements of SCCP levels and compositions in samples from background regions are particularly important.

Research on Application of WMSNs in Ubiquitous Learning Environment

WMSNs is one of the most cutting-edge technologies of the field of informatics, and compared to other sensor technology has broad prospects for development. WMSNs has very high service quality, larger multimedia data transmission amount, multimedia data flow model, a wide variety of application services and other characteristics. WMSNs support for education and teaching in support of ubiquitous learning environment. According to the characteristic of WMSNs, expounds the WMSNs support ubiquitous learning environment and function principle, as well as WMSNs ubiquitous learning environment application.