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Thermatel Model TD1/TD2 Thermal Dispersion Flow/Level/Interface Switch

Thermatel Model TD1/TD2 Thermal Dispersion Flow/Level/Interface Switch

A THERMATEL switch can be calibrated to detect the differ- ence between two media based upon the difference in thermal conductivity. This can include wet/dry, oil/water interface, air/foam and foam/liquid. The sensitivity of the switch can easily be adjusted for a wide range of conditions. Probes can be mounted from the top or side of the tank.

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Multi-level emulation of a volcanic ash transport and dispersion model to quantify sensitivity to uncertain parameters

Multi-level emulation of a volcanic ash transport and dispersion model to quantify sensitivity to uncertain parameters

There have been many studies investigating the processes that control the long-range dispersion of volcanic ash. The majority of these studies focus on a small number of sim- ulator inputs or parameters and change the parameters one at a time (OAT) to assess their impact on the predictions of volcanic ash transport. These studies test the difference be- tween the simulator output from a control or baseline case and the output from the perturbed cases. This approach is ap- pealing as it always calculates the change in the simulator away from a well-known baseline. Examples of studies that use this approach are Costa et al. (2006), Witham et al. (2007, 2012b), Webley et al. (2009), Dacre et al. (2011, 2015), De- venish et al. (2012a, b), Folch et al. (2012) and Grant et al. (2012). However, there are three main disadvantages of us- ing OAT analysis. First, the amount of parameter space that is sampled quickly reduces as the number of parameters con- sidered is increased (Saltelli and Annoni, 2010). Secondly, OAT tests ignore any interactions between parameters. For example, it is possible that perturbing two parameters sepa- rately in OAT tests might lead to negligible impacts, while the impact produced by perturbing them together might be much larger.
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Carbon monoxide levels along roadway

Carbon monoxide levels along roadway

AB STRACT: This paper predicts and compares the carbon monoxide (CO) concentration levels along Sembulan Road for years 2004 and 2014 using CAL3QHC air dispersion model at two major locations, i.e., at Sembulan Roundabout and Sutera Harbour Intersection, Kota Kinabalu, Sabah, Malaysia. The CO concentration “hot-spots” were also identified at Sutera Harbour Intersection, and the highest maximum 1-hr average ground level concentrations of CO modeled for Kpg. Air Sembulan located in the northeast of idling road was 9.33 ppm for year 2004. This study showed that there would be no extreme changes in CO concentration trends for year 2014 although a substantial increase in the number of vehicles is assumed to affect the level of CO concentrations. It was also found that the CO levels would be well below the Malaysian Ambient Air Quality Guidelines of 30 ppm for 1-hour Time-Weighted Average (TWA). Comparisons between the modeled and observed outputs using quantitative data analysis technique and statistical methods indicated that the CAL3QHC predicted results correlated well with measured data. It was predicted that receptors located near to the major intersection, in the long-term would be potentially exposed to relatively higher CO levels.
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Duobinary Modulation Format for Optical System- A Review

Duobinary Modulation Format for Optical System- A Review

Duobinary modulation is a format for transmitting R bits/sec using less than R/2 Hz of bandwidth [18]. Duobinary signalling, also named as correlative coding, was initially developed in the period of electronic communications as an efficient means for reaching the Nyquist limit [19]. Duobinary modulation format is based on producing a relationship between the adjacent bits at the transmitter. The main element in this process is duobinary generating filter, preferably composed of a simple feed-forward filter with a bit period delay in one arm followed by a sharp LPF having a cut off at B/2 [20]. The two main advantages attributed to this modulation format are increased tolerance to the effects of chromatic dispersion and an improved spectral efficiency. The first advantage enables transmission over longer spans of fiber without the need for dispersion compensation [21]. The second is assumed to enable closer spectral packing of channels in a wavelength-division-multiplexed (WDM) system [22]. Both these advantages are frequently attributed to the fact that the duobinary coding reduces the optical bandwidth of a full duty cycle near rectangular signal by a factor of 2 [23].
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Plume Dispersion in Four Pine Thinning Scenarios: Development of a Simple Pheromone Dispersion Model - Intermountain Journal of Sciences

Plume Dispersion in Four Pine Thinning Scenarios: Development of a Simple Pheromone Dispersion Model - Intermountain Journal of Sciences

A unique field campaign was conducted in 2004 to examine how changes in stand density may affect dispersion of insect pheromones in forest canopies. Over a 14-day period, 126 tracer tests were performed, and conditions ranged from an unthinned loblolly pine (Pinus taeda) canopy through a series of thinning scenarios with basal areas of 32.1, 23.0, and 16.1 m2ha-1. In this paper, one case study was used to visualize the nature of winds and plume diffusion. Also, a simple empirical model was developed to estimate maximum average concentration as a function of downwind distance, travel time, wind speed, and turbulence statistics at the source location. Predicted concentrations from the model were within a factor of 3 for 82.1 percent and 88.1 percent of the observed concentrations at downwind distances of 5 and 10 m, respectively. In addition, the model was used to generate a field chart to predict optimum spacing in arrays of anti-aggregation pheromone dispensers.
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Effect of Precursor Solvents on the Optical Properties of Copper Oxide Thin Films Deposited Using Spray Pyrolysis for Optoelectronic Applications

Effect of Precursor Solvents on the Optical Properties of Copper Oxide Thin Films Deposited Using Spray Pyrolysis for Optoelectronic Applications

Well adherent and transparent dark brown copper oxide thin films have been deposited on glass using alcohol and distilled water as solvents. Rutherford backscattering analysis revealed the aqueous films to be thicker than that of alcohol and the composition of the two films to be CuO with oxygen deficiency and cation compensation for alcohol and cation deficiency with oxygen compensation for the aqueous samples. The band gap calculated using direct transition for aqueous samples (1.79 eV) are higher than that of alcohol (1.58 eV) and for indirect transition, the values obtained are 2.60 and 2.86 eV for alcohol and aqueous samples respectively. The refractive index, which showed normal dispersion behavior have been used through single oscillator Sellmier model to calculate some optical and optoelectronic parameters. The loss tangent of the aqueous samples shows one broad dielectric loss peak while alcohol samples manifest three dielectric loss peaks. The observed peaks are probably indications of different dielectric relaxation mechanisms occurring in the two films. The optical conductivity manifests a high value at high energy of the incident photon indicating the high absorbing nature of the films and electron excitation. The values of the calculated optical mobility and the relaxation time of the alcohol samples are 400 % higher than that of aqueous samples while the charge carrier density and the optical resistivity values of the alcohol samples are 10 % and 21% greater than the values obtained for the aqueous samples. The results demonstrated that alcohol precursor leads to films of better properties which can be employed as solar cell absorber or optical windows.
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Micro scale Dispersion of Air Pollutants over an Urban Setup in a Coastal Region

Micro scale Dispersion of Air Pollutants over an Urban Setup in a Coastal Region

The micro-scale dispersion of various pollutants over a coastal region of south-east coast of Tamil Nadu has been studied. The micro-scale domain chosen for the present study is depicted in Figure 2. The study region covers a spatial coverage of 4 square kilometers, which contains a varied spatial terrain structures with 94 fields (green), 53 water bodies (deep blue), and 2 urban areas (brown). Dispersion of various pollutants is simulated using dis- persion solver of PANACHE. Atmospheric turbulence plays an important role in determining the dispersion. A turbulence model for atmospheric flows needs to capture 1) effects of both shear and thermal characteristics of atmospheric boundary layer and 2) the effects of shear due to obstacles and undulations of the terrain. Keeping in view of this, a turbulence model k - ε is implemented. The k - ε model is a 3D prognostic model that solves an equation for the turbulent kinetic energy and another equation for its dissipation rate [23]. It is suited for all types of flows including flow past obstacles and steeply undulating grounds. This capability of the model that takes care of flow around the obstacles would help in improving the representation of dispersion in the selected urban domain. In the present study, there is no availabil- ity of air pollution data (both emission inventory and air quality information). Hence, different scenarios are plan- ned with accidental emissions at two and three locations in the urban set up of micro-scale domain. Three loca- tions are chosen at different land characteristics are given in Figure 2. They are 1) the area of low-rise scattered buildings (named as HEP1 with + sign); 2) high-rise and dense building area (named as HEP2 with * sign) and green field (named as HEP3 with R sign).
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Spell Once, Summon Anywhere: A Two-Level Open-Vocabulary Language Model

Spell Once, Summon Anywhere: A Two-Level Open-Vocabulary Language Model

We show how the spellings of known words can help us deal with unknown words in open-vocabulary NLP tasks. The method we propose can be used to extend any closed- vocabulary generative model, but in this paper we specifically consider the case of neural language modeling. Our Bayesian generative story combines a standard RNN language model (generating the word tokens in each sentence) with an RNN- based spelling model (generating the letters in each word type). These two RNNs respectively capture sentence structure and word structure, and are kept separate as in linguistics. By in- voking the second RNN to generate spellings for novel words in context, we obtain an open-vocabulary language model. For known words, embeddings are naturally inferred by combining evidence from type spelling and token context. Comparing to baselines (including a novel strong baseline), we beat previous work and establish state-of-the-art results on multiple datasets.
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Nonlinear Optical Properties of Two Different Nanoassemblies of Polydiacetylene (PDA): PDA Nanovesicles and PDA Nanocrystals

Nonlinear Optical Properties of Two Different Nanoassemblies of Polydiacetylene (PDA): PDA Nanovesicles and PDA Nanocrystals

and establishing the ARINS setup to measure nonlinearity faster than 3 ps (described below), the non- linearity reported in this paper is purely of electronic origin. Moreover, instead of investigating the nonlinear response at a single wavelength, we have measured the third-order susceptibility in the spectral range of 720 nm - 820 nm. The subsequent spectral dispersion of second molecular hyperpolarizability has been analyzed in the framework of three-essential states model [16] and a correlation with the electronic and chemical structure of the sample has been discussed. The energy of two-photon state, transition dipole moments and the line width of transitions have also been estimated. In addition, proba- bly for the first time to the best of our knowledge and belief, we have also explored the influence of chain cou- pling effects facilitated by the chain packing geometry of PDAs on their third-order optical nonlinearity. To realize this objective, we have synthesized two different types of nanoassemblies of PDA, namely, PDA nanovesicles and
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Dynamic Model of the Price Dispersion of Homogeneous Goods

Dynamic Model of the Price Dispersion of Homogeneous Goods

Based on the idea that both the demand and the supply side of a market can take advantage of arbitrage opportunities the classic theory suggests that a homogenous good must sell for the same price, known as “ the law of one price ” [1]. However, even for homogeneous goods, empirical investigations show the existence of price dispersion [2]. Economists give four popular explanations for the origin of the price dispersion in product markets of homogeneous goods: amenities, heterogeneous costs, intertemporal price discrimination and search frictions. The first explanation suggests that identical goods sell at different prices because they are bundled with different amenities in different transactions [3]. The second states that firms at different locations have different costs causing prices to vary for similar goods [4]. Time dependent fluctuations of the price in order to satisfy different consumer groups [5- 8] and the limited ability of buyers to search the entire market [9-11] are other economic explanations for the price dispersion. Previous models of spatial and temporal price dispersion separate between different consumer groups (e.g. informed and uninformed consumers) and establish a price distribution for profit maximizing competing sellers [10,12].
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A dispersion model for the hepatic uptake and elimination of TCDD

A dispersion model for the hepatic uptake and elimination of TCDD

We have presented a model to describe the hepatic uptake and elimination of TCDD which includes the kinetics of TCDD-binding to the Ah receptor protein, induction of CYP1A2, and TCDD-binding to CYP1A2. The induction of CYP1A2 is based upon the fractional occupancy of the Ah receptor at a previous time to allow for the many intracellular processes which must occur before this Ah-receptor mediated activity is realized. Transport of solute in the blood region is described by a convection-dispersion equation to account for transport via bulk ow and turbulent diusion. Uptake of TCDD by the hepatic tissue is due to diusion of the solute across the cell membrane, with unbound TCDD the diusing species. Metabolism of TCDD, which is considered to be a detoxifying step, is modeled as a rst-order process. The resulting mathematical model is a nonlinear system of six partial dierential equations with time delay.
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Dynamic Price Dispersion in a Bertrand Edgeworth Model

Dynamic Price Dispersion in a Bertrand Edgeworth Model

This paper captures the dynamic properties of price dispersion by introducing an in nite time horizon model of Bertrand-Edgeworth competition. Speci cally, we consider a dynamic model of price competition in which sellers are endowed with one unit of the good and compete by posting prices in every period to maximize their expected pro ts with discounting. The number of buyers coming to the market in each period is random. Buyers each demand one unit of the good and have a common reservation price. They have full information regarding the prices posted by each rm in the market; hence, search is costless. We show that when excess demand occurs with positive probability, our model has a unique (symmetric) mixed-strategy equilibrium. In this equilibrium, sellers post prices according to non-degenerate distributions determined by the number of sellers, and the lowest possible market price, de ned as the greatest lower bound of the support of the distribution played by sellers, is decreasing in the number of sellers. In other words, inter rm price dispersion not only exists in every period, but it also persists over time.
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Inflation and Relative Price Dispersion in Canada: An Empirical Assessment

Inflation and Relative Price Dispersion in Canada: An Empirical Assessment

Les auteurs examinent empiriquement la relation entre différents aspects de l’inflation et la dispersion des prix relatifs au Canada en utilisant une courbe de Phillips spécifiée à l’aide d’un modèle de régression markovien. Ils analysent trois théories qui cherchent à expliquer les mouvements dans la dispersion des prix relatifs : le modèle à signaux brouillés, une extension de ce modèle et le modèle à coûts d’étiquetage. Les auteurs montrent que l’inflation anticipée, qui est captée par le modèle à coûts d’étiquetage, est l’aspect de l’inflation lié le plus étroitement à la dispersion des prix relatifs. Qui plus est, ce résultat semble robuste pour différentes spécifications. Toutefois, les auteurs ne peuvent pas rejeter complètement la significativité de l’incertitude (le modèle à signaux brouillés), surtout lorsqu’ils font appel à une mesure de l’inflation tendancielle. Ils constatent aussi que les variations positives et négatives imprévues de l’inflation totale ont des effets très asymétriques sur la dispersion des prix relatifs, mais que cette asymétrie n’est pas observée dans le cas de l’inflation tendancielle. Ce résultat donne à penser que la forte asymétrie découle principalement des composantes typiquement associées à des chocs d’offre, et non pas de la présence de rigidités nominales comme l’avance Aarstol (1999), dans la lignée de Ball et Mankiw (1992a et b).
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An organizational learning model with respect to level of organizational culture within an organization and level of isomorphism between organizations

An organizational learning model with respect to level of organizational culture within an organization and level of isomorphism between organizations

Institutionalization is the process where an organization's code of conduct, mission, policies, vision, and strategy become incorporated into the daily activities of its officers and other Institutionalization occurs when the culture of an organization becomes so well established that it is understood by people inside and outside of the organization. It aims at integrating fundamental values and objectives into the organization's culture and structure. Organizational culture is a of shared meaning held by members that distinguishes the organization from other organizations. The origin of culture as affecting an employee’s attitude and behavior can be traced back to the notion of institutionalization. When an stitutionalized, it takes on a life of its own, apart from its founders, managers or employees. Sony, Gillette, McDonald’s and Disney are some examples of organizations that have become valued for themselves, not merely for the goods or services they produce. Institutionalization produces common understandings among members about what is appropriate and fundamentally meaningful behavior in an organization. When an organization becomes institutional, shared meanings become evident to its when a strong organizational culture is Crossan, Lane and White (1999) explain that “institutionalizing is the process of ensuring that routinized nstitutionalization is the process that distinguishes organizational learning from individual and group learning as it is through this process that ideas are transformed into institutions of the organization. This implies that there is a deliberate effort to root knowledge at the organizational level so that it may persist and be repeated in the future with regularity and become recognized as an Institutionalization shows the extent to which norms, decisions and beliefs are becoming incorporated into the normal, ongoing activities of the organization. In this has been introduced to understand organizational learning patterns under various degrees of institutional isomorphism. This is in no way saying that one learning method is superior to another, it just proposes a model to predict which learning procedure most likely occurs under what conditions.
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On the Thermodynamics of a Two Dimensional Electron Gas with Non Parabolic Dispersion

On the Thermodynamics of a Two Dimensional Electron Gas with Non Parabolic Dispersion

function of total two-dimensional electron concentration (Figure 3). Stepped changes of the DOS are manifested in the form of fracture. These fractures can be seen clearly in calculated lines (Figure 3) and these lines explain the experimental data [7]. The num- ber of filled subbands increases at the wide QW and high temperatures (Figure 4).

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TRANSFoRm : implementing a learning healthcare system in Europe through embedding clinical research into clinical practice

TRANSFoRm : implementing a learning healthcare system in Europe through embedding clinical research into clinical practice

On a conceptual level, our work establishes a standard-based method for connecting clinical research study systems and EHR repositories. This has been an area of interest for a number of research bodies. Particularly related to this work are CDISC-IHE Healthcare Link profiles [6], integration standards for connecting healthcare and clinical research, particularly the Retrieve Form for Data Capture Profile (RFD) and the Clinical Research Document Profile (CRD). RFD provides a method for gathering data within a user’s current application to meet the requirements of an external system, while the CRD describes the content pertinent to the clinical research use case required within the RFD pre-population parameter. These profiles focus on web services for retrieving forms and using HL7 Continuity of Care (CCD) format [16] for pre-population of eCRFs from external CDMS to display within EHR systems. TRANSFoRm adopted an alternative strategy, by which eCRFs are deployed from within the EHR system itself. From our experience, EHR vendors in Europe are still in the early stage of supporting HL7 CCD and IHE profiles. On the other hand, these standardisation efforts do not yet offer the necessary semantic linkage required for lossless data sharing across systems.
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Dispersion Flattened Optical Fiber Design for Large Bandwidth and High-Speed Optical Communications Using Optimization Technique

Dispersion Flattened Optical Fiber Design for Large Bandwidth and High-Speed Optical Communications Using Optimization Technique

By applying the introduced design method, the optimized RII triple- clad optical fiber is reported. It is shown that the obtained optimized case introduces so interesting features to be used for optical communication. We show that this structure have 17400 Km dispersion length, 1.0016 pulse broadening factor after 200 Km, and 197.8 Gb/sec at 100 Km. Based on these reported results the introduced fiber illustrate good performance for high speed data transmission lines and especially OTDM applications. Also, this methodology is capable to shift the zero dispersion wavelength to an arbitrary requested wavelength and introduce possible minimum dispersion slope. In the simulated results, we discovered that ∆ is critical parameter in the optimization procedure for changing input pulse from chirped to without chirping. Finally, the F BF introduced fitness function let the
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CO2PipeHaz: Quantitative hazard assessment for next generation CO2 pipelines

CO2PipeHaz: Quantitative hazard assessment for next generation CO2 pipelines

The chief objective of WP1.5 was the modelling of far-field dispersion of carbon dioxide resulting from accidental pipeline releases, including the importance of terrain and the wind-field on the dispersion behaviour. This was undertaken using two different commercial computational fluid dynamic codes: FLACS [10]; and ANSYS-CFX [11]. In both cases, the continuous gas-phase was solved in the Eulerian reference frame, whilst a Lagrangian formulation was used for the dispersed particle phase. When dealing with poly-dispersed turbulent two-phase flows, the Lagrangian reference frame appears to be the natural choice for treating the dispersed phase, in which individual particles or representative numerical particles, are tracked and their characteristics are evaluated as they move through the turbulent flow field. Moreover, this approach is well adapted for modelling particle interactions with obstacles and particle deposition [34], which are processes that need to be accounted for in the systems studied here. Considered in the modelling are non-compressible, non-reacting fluid-particle flows without collisions between particles. The physical phenomena of interest are the dispersion, vaporization, and deposition of particles and the coupling between the continuous phase and the dispersed phase. Further information regarding the equations employed and the solution methods applied can be found in [11] and [35]
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Application of a new approach in an analytical model to simulate the dispersion of a radioactive pollutant

Application of a new approach in an analytical model to simulate the dispersion of a radioactive pollutant

Prediction models of radioactive substances in the atmosphere is a matter of great importance for the prevention of environmental impacts in the event of an accident. Emergency plans are formulated on the basis of possible air concentration scenarios, and therefore they use mathematical models of contaminant dispersion in the atmosphere, which are able to relate causes (sources) to relative effects (pollutant concentration). This type of problem is represented by the classical advection-diffusion equation (Seinfeld and Pandis, 1998). The major analytical solutions in the literature for the advection-diffusion equation are for very specific cases, generally considering constant or simple turbulent diffusivity coefficients, for some references see the work of (Moreira et al., 2009). However, many advances were obtained using the GILTT method (Wortmann et al., 2005; Moreira et al., 2006, Buske et al., 2012a, 2012b Vilhena et al., 2012). For the solution of partial differential problems, this integral transformation technique combines an expansion in series with an integration. In the expansion a trigonometric, obtained from an auxiliary Sturm-Liouville problem, is used.
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Granular Drag and the Kinetics of Jamming

Granular Drag and the Kinetics of Jamming

Dispersions in Boger fluids exhibit a dramatically different behavior. Before even quantifying the interfacial speeds, we see the effect of viscoelasticity in the polymeric fluid. While the lower interfaces in both the polymeric and Newtonian cases have well-defined, single-valued slopes, the supernatant-interface, that in the Newtonian case agrees so well with the expectations of Ref. [34], seems to settle quickly at one constant speed, then transition to a second, slower constant speed. By continuity, since the jamming front maintains the same constant speed until reaching steady- state, the concentration of the dispersion in the polymeric fluid must be evolving with time. Nonetheless, we can at least compare the initial behavior to that of the Newtonian dispersions. Again, we plot the supernatant-interface speed, this time for viscoelastic dispersions of a variety of grainsizes and initial concentrations in Fig. 4.6(b), normalized according to Eq. (4.1.1). The data are collected using both scattered light imaging and X-ray imaging, so both types of Boger fluid are included, and in all cases the behavior at least scales in a manner consistent with Eq. (4.1.1). The magnitudes of the measurements are systematically larger than expectation. This is likely a consequence of the fluid’s slight shear thinning, which we did not account for in our calculations of the normalization. This result suggests that far from the front the grains’ behavior is not affected by the viscoelasticity of the fluid, but as they approach the jamming front grains slow down, and pile up in a fashion similar to a traffic jam, before undergoing a long consolidation into the packed state.
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