Top PDF Description and implementation of a MiXed Layer model (MXL, v1.0) for the dynamics of the atmospheric boundary layer in the Modular Earth Submodel System (MESSy)

Description and implementation of a MiXed Layer model (MXL, v1.0) for the dynamics of the atmospheric boundary layer in the Modular Earth Submodel System (MESSy)

Description and implementation of a MiXed Layer model (MXL, v1.0) for the dynamics of the atmospheric boundary layer in the Modular Earth Submodel System (MESSy)

For the lower boundary conditions, there are two possi- bilities. On one hand, MXL/MESSy offers the possibility to use interactive emission (via the ONEMIS (Kerkweg et al., 2006b) and MEGAN (Guenther et al., 2006) submodels), dry deposition (DDEP; Kerkweg et al., 2006a) and land sur- face parametrizations (Sect. 2.7). In these submodels, land surface-ABL exchange is calculated as function of land sur- face and ABL characteristics, like stomatal resistance and air temperature. On the other hand, it is possible to pre- scribe emissions and surface heat fluxes following simpli- fied functions for the users who like to keep full control over the boundary conditions of the model (Sect. 2.5). In that way, MXL/MESSy can for instance be used to evaluate the sensitivity of the chemistry in the ABL to uncertainties in emission estimates. Further, OFFEMIS (Kerkweg et al., 2006b) allows for the extraction of emission time series from an emission database, which is read by IMPORT. Addition- ally, the organic aerosol submodel ORACLE (Tsimpidi et al., 2014), allows for the representation of the organic aerosol composition and evolution.
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A modified Ekman layer model

A modified Ekman layer model

Abstract. A modification of the Ekman layer that is able to systematically account for the effects of curvature of the velocity fluctuation streamlines is developed, using the description of turbulent motions. These effects are accounted for through the average vector product of the velocity fluctuations and the local curvature vector of their streamlines at each flow field point. It is shown that this approach enables quantifying the impact of several phenomena (such as the Stokes drift or the incessant generation of vortices with a prevailing orientation of rotation, intrinsic to surface-driven geophysical flows) on the formation of the Ekman layer. The outcome of the suggested modification is compared with the relevant data measured in the Drake Passage.
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MetUM-GOML: a near-globally coupled atmosphere–ocean-mixed-layer model

MetUM-GOML: a near-globally coupled atmosphere–ocean-mixed-layer model

long spin-up periods to attain a balance within the coupled system. They can also exhibit significant drifts and biases in the mean state, which can be of equal magnitude or larger than the desired signal (e.g. ENSO, decadal ocean variability, responses to greenhouse-gas or aerosol forcing). For example, many coupled models have a large cold equatorial SST bias in the tropical Pacific which inhibit their ability to simulate key

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Implementation of a hybrid particle code with a PIC description in r-z and a gridless description in phi into OSIRIS

Implementation of a hybrid particle code with a PIC description in r-z and a gridless description in phi into OSIRIS

For many plasma physics problems, three-dimensional and kinetic effects are very important. However, such simulations are very computationally intensive. Fortunately, there is a class of problems for which there is nearly azimuthal symmetry and the dominant three-dimensional physics is captured by the inclusion of only a few azimuthal harmonics. Recently, it was proposed [1] to model one such problem, laser wakefield acceleration, by expanding the fields and currents in azimuthal harmonics and truncating the expansion after only the first harmonic. The complex amplitudes of the fundamental and first harmonic for the fields were solved on an r-z grid and a procedure for calculating the complex current amplitudes for each particle based on its motion in Cartesian geometry was presented using a Marder’s correction to maintain the validity of Gauss’s law. In this paper, we describe an implementation of this algorithm into OSIRIS using a rigorous charge conserving current deposition method to maintain the validity of Gauss’s law. We show that this algorithm is a hybrid method which uses a particles-in-cell description in r-z and a gridless description in φ. We include the ability to keep an arbitrary number of harmonics and higher order particle shapes. Examples, for laser wakefield acceleration, plasma wakefield acceleration, and beam loading are also presented and directions for future work are discussed.
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Lat. Am. j. solids struct.  vol.14 número11

Lat. Am. j. solids struct. vol.14 número11

This work presents a detailed description of the formulation and implementation of the Atomistic Finite Element Method AFEM, exemplified in the analysis of one- and two-dimensional atomic domains governed by the Lennard Jones interatomic potential. The methodology to synthesize element stiffness matrices and load vectors, the potential energy modification of the atomistic finite elements (AFE) to account for boundary edge effects, the inclusion of boundary conditions is carefully described. The conceptual rela- tion between the cut-off radius of interatomic potentials and the number of nodes in the AFE is addressed and exemplified for the 1D case. For the 1D case elements with 3, 5 and 7 nodes were ad- dressed. The AFEM has been used to describe the mechanical behavior of one-dimensional atomic arrays as well as two- dimensional lattices of atoms. The examples also included the anal- ysis of pristine domains, as well as domains with missing atoms, defects, or vacancies. Results are compared with classical molecular dynamic simulations (MD) performed using a commercial package. The results have been very encouraging in terms of accuracy and in the computational effort necessary to execute both methodologies, AFEM and MD. The methodology can be expanded to model any domain described by an interatomic energy potential.
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Characterization of a boreal convective boundary layer and its impact on atmospheric chemistry during HUMPPA-COPEC-2010

Characterization of a boreal convective boundary layer and its impact on atmospheric chemistry during HUMPPA-COPEC-2010

residual mixed layer (in our case around 9:30 LT). Then both layers merge and become one mixed boundary layer, as illustrated in Fig. 2. In the MXL model this merging of two atmospheric layers into one is instantaneous. However, in reality it can take some time due to inhomogeneous ABL conditions and the time it takes for thermals to rise from the surface to the top of the residual layer. In this section we will show that this process can

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Corrigendum to "Nonlinear dynamics approach to the  predictability of the Cane–Zebiak coupled ocean–atmosphere model"  published in Nonlin. Processes Geophys., 21, 155–163, 2014

Corrigendum to "Nonlinear dynamics approach to the predictability of the Cane–Zebiak coupled ocean–atmosphere model" published in Nonlin. Processes Geophys., 21, 155–163, 2014

The correct sentence of Sect. 4 should read as follows: “It is worth noting that the ocean component of this model is essentially made of two prognostic equations: one for the mixed layer thermodynamics equation for SST, a ther- mocline depth equation for upper ocean dynamics, along with SST–gradient-wind relation, and the wind–equatorial- upwelling relation.”

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Numerical enhancements and parallel GPU implementation of the TRACEO3D model

Numerical enhancements and parallel GPU implementation of the TRACEO3D model

Synopsis: A description of the numerical enhancements of the TRACEO3D ray tracing model is presented in this chapter, namely, the Simplex-based eigenray search, and the opti- mization of ray influence calculations. The eigenray Simplex-based search was developed to efficiently and accurately calculate 3D eigenrays, providing predictions that account for hor- izontal effects. Ray influence calculations were also improved with the main goal of reducing the computational time, which often increases drastically as range, number of rays and num- ber of sensor increases. The structure of this chapter is as follows: Section 3.1 presents the eigenray Simplex-based search, while Section 3.2 describes the procedures that compound the ray influence calculations.
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Model for estimation of enterprise management system potential: description and study

Model for estimation of enterprise management system potential: description and study

The analysis response surface models with different combinations of values of input parameters (i.e., potential for the units of the enterprise management system) shows that the total potential system with a wide range of potential values for the units sets to about 0,5. To ensure a higher level of potential need to provide the three potentials (the structural and functional potential, the informative and technical potential, the management personnel potential) not less than 0,8. However, it is shown that the potential of preparing, adoption and implementation of management decisions negligible impacts on overall management system potential. This finding further confirms the thesis about the combined nature of the potential of preparing, adoption and implementation of management decisions and its dependence on the optimum combination of objective and subjective components of management processes in the enterprise.
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Service quality strategy implementation : a model and the case of the Algarve hotel industry

Service quality strategy implementation : a model and the case of the Algarve hotel industry

The gap, static, dynamic and mixed models are now confronted, in this paper, with sample data from the four and five star hotels of the Algarve (FFSHA). The data does not provide evidence against the models thus supporting their validity. This tentative validation of the models thus provides some relevant theoretical contributes to the service quality and the strategy implementation literatures. It also raises some concerns about possible inconsistent management practices during the implementation of a service quality strategy and provides some insights to managers interested in implementing such a strategy. Sample data is also used, elsewhere, to describe (1) how FFSHA are implementing service quality strategies; (2) how they prevent and eliminate SQGs; (3) how management practices differs according to hotel ownership: international chains, portuguese chains, and independent hotels; and (4) what can be learned from the differences (Cândido, 2001 & 2003).
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Derivation and assessment of a mixed layer sub-mesoscale model

Derivation and assessment of a mixed layer sub-mesoscale model

is still incomplete, numerical simulations of increasingly higher resolution have been a rich source of information that serves as a test bed for parameterizations of the sub- mesoscale fluxes to be then used in low resolution OGCMs to represent structures they cannot resolve. If one considers that the highest resolution of about 1/10 ◦ stand alone OGCMs can resolve structures of about 10 km size which is 10 times larger than sub-

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Adaptability and stability of maize varieties using mixed model methodology

Adaptability and stability of maize varieties using mixed model methodology

Abstract - The objective of this study was to evaluate the performance, adaptability and stability of corn cultivars simultaneously in unbalanced experiments, using the method of harmonic means of the relative performance of genetic values. The grain yield of 45 cultivars, including hybrids and varieties, was evaluated in 49 environments in two growing seasons. In the 2007/2008 growing season, 36 cultivars were evaluated and in 2008/2009 25 cultivars, of which 16 were used in both seasons. Statistical analyses were performed based on mixed models, considering genotypes as random and replications within environments as fixed factors. The experimental precision in the combined analyses was high (accuracy estimates > 92 %). Despite the existence of genotype x environment interac- tion, hybrids and varieties with high adaptability and stability were identified. Results showed that the method of harmonic means of the relative performance of genetic values is a suitable method for maize breeding programs.
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Fabrication of in situ composite layer on cast steel

Fabrication of in situ composite layer on cast steel

The study describes the technology of fabrication of composite layers in cast steel reinforced with titanium carbides. In the process under discussion, the reinforcing TiC phase is formed in situ from the substrates deposited on mould cavity, where the said substrates under the effect of heat supplied by molten metal poured into mould (1823K) undergo a synthesis in the SHS reaction. An outcome of this process is the formation, within the casting surface, of a layer from 550 to 1200µm thick. Carbides produced in this synthesis have the size from 0,5 to 20µm and a non-typical spheroidal shape. The hardness of the produced layer examined in function of the distance from the casting surface is from 700 to 1134 HV, and is determined by volume fraction of the reinforcing TiC phase. To better document the type of microstructure obtained in the produced material, metallographic and structural examinations were carried out using the method of scanning electron microscopy (SEM), X-ray microanalysis (EDS/EDX), and phase analysis (XRD). To check the mechanical properties of the examined material, hardness was measured by the Vickers test.
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Mixed layer variability and chlorophyll <i>a</i> biomass in the Bay of Bengal

Mixed layer variability and chlorophyll <i>a</i> biomass in the Bay of Bengal

waters of the Bay. An examination of the monthly mean climatology of river discharge of 5 major rivers Ganges, Brahmaputra, Irrawady, Godavari, and Krishna showed that the freshwater discharge dominated during July to October (Fig. 5d). The spreading of low salinity waters (< 32 psu) were seen from the northern Bay towards the south and also along eastern and western boundary (see the blue cross-hatch in Fig. 5a–c) with

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Measurement of the effectiveness of non-profit organizations

Measurement of the effectiveness of non-profit organizations

In the fourth step, it was determined that one of the important indicators is effectiveness of realization one of the main activities, namely "International Academic Course BEST». This project is a major source to achieve its purposes by organization. The format of the event is about 20 students from all Europe gathered at a university in the local branch (in this case based on ZNTU) and for about two weeks they listen lecture course and visit some local factories on topic predefined by organizers. It may be a technical subject (on ZNTU base were conducted courses on Automation, Aircraft building, Energy, etc.) and economic subjects, which will help in future employment of participants (Financial crisis, Management and Marketing).
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Surface Morphology And Photoluminescence Properties Of A-GaAsSe Detector

Surface Morphology And Photoluminescence Properties Of A-GaAsSe Detector

3-1 M ORPHOLOGY P ROPERTIES OF GaAs:Se/ C -S I T HIN F ILM Figure (1) show the structure of GaAs:Se thin films that have been deposited on glass substrates and annealed at RT ,373 and 473 K with thicknesses 0.5 µm. The surface morphology of the GaAs:Se films as observed from the AFM micrograph confirms that the grains are uniformly distributed. We can notice that GaAs:Se films deposited at room temperature and annealed to 373K are amorphous while the films annealed to 473K are crystalline in nature . Table (1) shows the value of average roughness and average grain . It was observed from this table that the average roughness and the average grain size value decreases with increasing the annealing temperature.
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Simultaneous Determination Of Adjusted Ranks Of Sample Observations And Their Sums And Products

Simultaneous Determination Of Adjusted Ranks Of Sample Observations And Their Sums And Products

Abstract: This paper proposes a systematic method for the simultaneous determination of adjusted ranks of sample observations and their sums and products adjusted for possible presence of tied observations in the sampled populations for use in further analyses. When computations involving paired data sets, as in the computation of the Spearman Rank Correlation Coefficient, this procedure intrinsically obtained the sums of ranks, products of ranks and sums of squares of ranks, automatically adjusting these sums for more accurate results. The proposed method is illustrated with some data and used to estimate ties adjusted Spearman Rank Correlation Coefficient and the bias that would have arisen if there were no adjustments for ties in the sampled populations.
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Description of the use of integrative mixed method in neonatal nursing

Description of the use of integrative mixed method in neonatal nursing

Qualitative data were obtained concomitantly with quantitative data by means of an in-depth interview with premature infants’ mothers soon after application of PSI at the preterm follow-up clinic three months after discharge from the neonatal unit. The following guiding questions were used during interviews: For you, what is it like to take care of your premature infant after discharge from the NICU? What are your feelings about the experience with the premature infant at home in those early months? Each issue had a road map on topics addressed such as child care, difficulties with the care, fears, anxieties and anguish experienced by the mother after the premature infant’s discharge from hospital. Interviews were audio recorded, and the content was validated by participants.
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ORDINARY LEAST SQUARES ESTIMATION OF A DYNAMIC GAME MODEL

ORDINARY LEAST SQUARES ESTIMATION OF A DYNAMIC GAME MODEL

Analogous closed-form estimation is also possible in some models with common unobserved heterogeneity and/or for empirical games with multiple equilibria. This follows since, in prin- ciple, Hotz and Miller’s (1993) two-step approach can be used whenever a nonparametric estimator is available to construct an empirical model that is consistent with the observed data in the first step. For an example, see Aguirregabiria and Mira (2007, Section 3.5), where non- parametric identification results of Kasahara and Shimotsu (2009) can be applied. Therefore we are hopeful that closed-form estimation based on minimizing expected payoffs is generally possible beyond the basic setup of our game, particularly given recent identification results for games with multiple equilibria (Aguirregabiria and Mira, 2013; Xiao, 2014) and other dynamic models with latent state variables (e.g., Hu and Shum, 2012).
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Effect of water glass modification with nanoparticles of zinc oxide on selected physical and chemical properties of binder and mechanical properties of sand mixture

Effect of water glass modification with nanoparticles of zinc oxide on selected physical and chemical properties of binder and mechanical properties of sand mixture

Figures 3,4,5 show changes in the value of the contact angle in a quartz-binder system. Figure 3 illustrates the quartz wetting characteristics using an unmodified binder, while Figures 4 and 5 show the results of analogical measurements taken for the binder modified with 1 or 3 wt.% of the modifier.

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