scholarly journals New Screening tool for Obtaining Concentration Statistics of Pollution Generated by Rivers in Estuaries

Water ◽  
2018 ◽  
Vol 10 (5) ◽  
pp. 639 ◽  
Author(s):  
Morena Galešić ◽  
Roko Andričević ◽  
Vladimir Divić ◽  
Robert Šakić Trogrlić
Keyword(s):  
Screening Tool ◽  
Near Field ◽  
Implementation Process ◽  
Field Approximation ◽  
Coastal Pollution ◽  
Ensemble Averaging ◽  
Tidal Forces ◽  
Social Fund ◽  
Concentration Statistics ◽  
Water Quality Deterioration

Rivers represent an essential pathway for waterborne transport, and therefore estuaries are critical coastal areas for a pollution hazard that might lead to eutrophication and general water quality deterioration. When addressing these problems, the decision makers and coastal managers often need additional skills and specialists, so they engage consultants in developing models and providing potential solutions. Different stakeholders’ interests present a challenge in the implementation process of proposed solutions. Nevertheless, if the relevant institutions were presented with a screening tool, enabling them with a certain level of solution ownership, potentially more involvement would occur. There are numerous intertwined physical processes present in the estuary ecosystem, including river discharge, tidal forces, wind-induced stress and water density variations. This research utilizes an analytical model based on ensemble averaging and near-field approximation of the advective-diffusion equation for the case of continuous, steady, conservative solute transport in a stratified, river-dominated estuary. Such an approach significantly reduces the costs and time needed to obtain enough measured data required for common statistical analysis or the need for a more complex numerical model. The developed methodology is implemented into a simple software named CPoRT (Coastal Pollution Risk Tool) within a recently conducted research project funded by European Social Fund.

scholarly journals 112 A Critical Evaluation of the VIP Tool in Identifying Frailty in the Older Adult in a Kerry Hospital

2019 ◽  
Vol 48 (Supplement_3) ◽  
pp. iii17-iii65
Author(s):  
Amanda Brolly ◽  
Liza Bergin ◽  
Paudie McQuinn ◽  
Shinann Buckley O’Sullivan ◽  
Corina Naughton
Keyword(s):  
Older Adult ◽  
Screening Tool ◽  
Critical Evaluation ◽  
Implementation Process ◽  
Adverse Health Outcomes ◽  
Increased Risk ◽  
Acute Confusion ◽  
Reduced Mobility ◽  
Therapy Team ◽  
Selection Of

Abstract Background The Variable Indicative of Placement risk (VIP) is a tool that was developed in Belgium to identify older people at risk of adverse health outcomes at the time of hospital admission (Vandewoude et al 2008). VIP is a simple 3-item screening tool for the selection of hospitalized patients aged 70 and older who are at increased risk of problems at discharge. It asks three simple questions about frailty factors already existing before admission. This tool has been validated to select patients who would benefit from a geriatric assessment (Vandewoude et al 2008). As part of the implementation process, it is important to critically review VIP as a frailty screening and selection tool for the Frailty Intervention Therapy Team (FITT) service compared to age criteria alone. There is a risk that patients screening negative on VIP could be inappropriately excluded from the FITT review. Methods All patients over 75 were screened using the VIP tool over a 6 week period by nursing staff in triage The “Think Frail” tool was also used to screen all patients reviewed by FITT- both positive & negative VIP Data was retrospectively gathered and VIP positive/negative patients reviewed by FITT were analysed Results 55% were VIP positive 45% were VIP negative 16.5% of VIP negative patients were screened positive for frailty using the “Think Frail” tool We found VIP under-recognised patients presenting with reduced mobility (5.5%, n=20), acute confusion (2.7%, n=10) and polypharmacy (8.1%, n=29), all potentially modifiable frailty Conclusion The VIP tool is not sensitive to identifying the presence of pre-frailty markers including falls, polypharmacy and acute confusion. Further research is needed into the use of the VIP tool in Ireland. It is recommended that this tool is not used independently to identify frailty in the ED.

scholarly journals Optical bistability in two-dimensional nonlinear composites of coated cylinders with nonlinear core and graded shell

2020 ◽  
Vol 7 ◽  
pp. 6
Author(s):  
Ya M. Wu ◽  
Guo Q. Chen ◽  
Wen C. Wu ◽  
Yi X. Wang ◽  
Yang Huang
Keyword(s):  
Optical Bistability ◽  
Near Field ◽  
Mean Field ◽  
Field Approximation ◽  
Mean Field Approximation ◽  
Geometrical Parameters ◽  
Core Radius ◽  
The Core ◽  
Nonlinear Composite ◽  
Incident Frequency

The intrinsic optical bistability of the nonlinear composite consisting of coated cylinders with nonlinear core and graded Drude shell is investigated with self-consistent mean-field approximation. We derive the nonlinear equation of near field for such graded composite in the quasistatic limit. We demonstrate that the bistability threshold and the bistable width are highly dependent on the core radius, the incident frequency, and the graded coefficient of the coated cylinder inclusion. It is found that the optical bistability appears only when the core radius and the incident frequency satisfy some specific conditions. Therefore, the optical bistability for nonlinear composite materials may be optimized by the suitable adjustment of the physical and geometrical parameters. Our results may be helpful for the design of the nonlinear device with appropriate bistability.

scholarly journals Far- and near-field approximation for diffraction radiation

2013 ◽  
Vol 309 ◽  
pp. 194-197
Author(s):  
V. Shpakov ◽  
S.B. Dabagov ◽  
M. Castellano ◽  
A. Cianchi ◽  
K. Honkavaara ◽  
...  
Keyword(s):  
Near Field ◽  
Field Approximation ◽  
Diffraction Radiation

Near Field Representations of the Acoustic Green's Function in a Shallow Ocean with Fluid-Like Seabed

2007 ◽  
Vol 14 (1) ◽  
pp. 109-123
Author(s):  
Robert Gilbert ◽  
Miao-Jung Ou
Keyword(s):  
Green’S Function ◽  
Green's Function ◽  
Near Field ◽  
Sound Field ◽  
Hankel Transform ◽  
Field Approximation ◽  
Construction Scheme ◽  
Stratified Ocean ◽  
Asymptotic Representations ◽  
Layer Waveguide

Abstract In this paper, the near-field approximation of the acoustic Green's function in a two-layer waveguide is constructed by using a variation of the method of Ahluwalia and Keller [Exact and asymptotic representations of the sound field in a stratified ocean, Springer, 1977]. The relation between the constructed multiple-scattering representation (suitable for near-field) and the Hankel transform representation (suitable for mid-range) is also discussed in this paper. The construction scheme presented in this paper can be generalized for an N-layer waveguide.

A method for determining the effective conductivity of dispersions of particles

1990 ◽  
Vol 430 (1879) ◽  
pp. 285-313 ◽  
Keyword(s):  
Effective Conductivity ◽  
Near Field ◽  
Field Approximation ◽  
Spherical Particles ◽  
Far Field ◽  
Particle Interactions ◽  
Stokesian Dynamics ◽  
System A ◽  
Method Formulation ◽  
Capacitance Matrix

A general method is developed to predict the effective conductivity of an infinite, statistically homogeneous suspension of particles in an arbitrary (ordered or disordered) configuration. The method follows closely that of ‘stokesian dynamics’, and captures both far-field and near-field particle interactions accurately with no convergence difficulties. This is accomplished by forming a capacitance matrix, the electrostatic analogue of the low-Reynolds-number resistance matrix, which relates the monopole (charge), dipole and quadrupole of the particles to the potential held of the system. A far-field approximation to the capacitance matrix is formed via a moment expansion of the integral equation for the potential. The capacitance matrix of the infinite system is limited to finite number of equations by using periodic boundary conditions, and the Ewald method is used to form rapidly converging lattice sums of particle interactions. To include near-field effects, exact two-body interactions are added to the far-field approximation of the capacitance matrix. The particle dipoles are then calculated directly to determine the effective conductivity of the system. The Madelung constant of cohesive energy of ionic crystals is calculated for simple and body-centred cubic lattices as a check on the method formulation. The results are found to be in excellent agreement with the accepted values. Also, the effective conductivities of spherical particles in cubic arrays are calculated for particle to matrix conductivity ratios of infinity, 10 and 0.01.

scholarly journals Geodesic deviation, Raychaudhuri equation, Newtonian limit, and tidal forces in Weyl-type f(Q, T) gravity

2021 ◽  
Vol 81 (2) ◽  
Author(s):  
Jin-Zhao Yang ◽  
Shahab Shahidi ◽  
Tiberiu Harko ◽  
Shi-Dong Liang
Keyword(s):  
Field Approximation ◽  
The Body ◽  
Newtonian Limit ◽  
Raychaudhuri Equation ◽  
Geodesic Deviation ◽  
Weyl Geometry ◽  
Matter Coupling ◽  
Tidal Forces ◽  
Deviation Equation ◽  
Geodesic Deviation Equation

AbstractWe consider the geodesic deviation equation, describing the relative accelerations of nearby particles, and the Raychaudhuri equation, giving the evolution of the kinematical quantities associated with deformations (expansion, shear and rotation) in the Weyl-type f(Q, T) gravity, in which the non-metricity Q is represented in the standard Weyl form, fully determined by the Weyl vector, while T represents the trace of the matter energy–momentum tensor. The effects of the Weyl geometry and of the extra force induced by the non-metricity–matter coupling are explicitly taken into account. The Newtonian limit of the theory is investigated, and the generalized Poisson equation, containing correction terms coming from the Weyl geometry, and from the geometry matter coupling, is derived. As a physical application of the geodesic deviation equation the modifications of the tidal forces, due to the non-metricity–matter coupling, are obtained in the weak-field approximation. The tidal motion of test particles is directly influenced by the gradients of the extra force, and of the Weyl vector. As a concrete astrophysical example we obtain the expression of the Roche limit (the orbital distance at which a satellite begins to be tidally torn apart by the body it orbits) in the Weyl-type f(Q, T) gravity.

Infrared Radiative Properties of Thin Polyethylene Coating Pigmented With Titanium Dioxide Particles

2009 ◽  
Vol 132 (2) ◽  
Author(s):  
Mehdi Baneshi ◽  
Shigenao Maruyama ◽  
Atsuki Komiya
Keyword(s):  
Particle Size ◽  
Volume Fraction ◽  
Near Field ◽  
Field Approximation ◽  
Anisotropic Scattering ◽  
Radiative Properties ◽  
Emission Model ◽  
Tio2 Pigment ◽  
Pigmented Coatings ◽  
Thin Polyethylene

The infrared (IR) radiative properties of TiO2 pigment particles must be known to perform thermal analysis of a TiO2 pigmented coating. Resins generally used in making pigmented coatings are absorbing at IR wavelengths, which means that the conventional Mie solution (MS) may not be adequate in this domain. There are two approaches to evaluating radiative properties in an absorbing medium: far field approximation (FFA) and near field approximation (NFA). In this study, after reviewing these two approaches, we evaluated the radiative properties of TiO2 particles in polyethylene resin as an absorbing matrix in the wavelength range of 1.7–15 μm based on the MS, FFA, and NFA. We then calculated the effective scattering and absorption coefficients for different models. To investigate the effect of the particle size and volume concentration on the transmittance of IR wavelengths, we made a nongray radiative heat transfer in an anisotropic scattering monodisperse pigmented layer, with independent scattering using the radiation element method by the ray emission model. The results showed that all three approaches predicted similar results in the particle size domain and volume fraction range utilized in pigmented coatings.

Concentration statistics of solute transport for the near field zone of an estuary

2016 ◽  
Vol 94 ◽  
pp. 424-440 ◽  
Author(s):  
Morena Galesic ◽  
Roko Andricevic ◽  
Hrvoje Gotovac ◽  
Veljko Srzic
Keyword(s):  
Solute Transport ◽  
Near Field ◽  
Field Zone ◽  
Concentration Statistics

scholarly journals COMPARISON OF METRICS FROM RETARDED INTEGRALS AND TRANSVERSE TRACELESS SUBGAUGE

2013 ◽  
Vol 28 (19) ◽  
pp. 1350093
Author(s):  
R. A. LEWIS ◽  
G. MODANESE
Keyword(s):  
Gravitational Field ◽  
Boundary Conditions ◽  
Near Field ◽  
Riemann Tensor ◽  
Far Field ◽  
Time Varying ◽  
Point Particles ◽  
Tidal Forces ◽  
Formal Framework ◽  
Linear Field

The time-varying gravitational field produced by a Weber bar is used to explore physical and mathematical features of the linearized Einstein equation. We present a self-contained formal framework for the treatment of the linear field, that is applicable to several sources for which the standard quadrupolar formulas are not adequate. The expressions for retarded integrals reveal a singularity associated with boundary conditions. Results from the transverse traceless subgauge are compared with the radiation calculated from retarded integrals. Lienard–Wiechert potentials are used in a treatment of the Weber bar as a collection of point particles and further possible applications are outlined. The Riemann tensor clarifies the transition from near-field geodesic forces to tidal forces in the far field.

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