Spatial Variation Of Potential Research Articles

Groundwater potential zoning by integrating multi-criteria decision and bivariate analysis methods – a case study on Cheyyar River Basin, Tamil Nadu, India

The study aims to improve the pairwise decision matrix of the widely used analytical hierarchy process (AHP) to generate groundwater potential zones for Cheyyar River Basin through multi-influencing factor (MIF) and bivariate analysis. MIF prioritizes 11 time-independent input thematic layers, and Cramer’s V dependency value from bivariate analysis is used to assign the decision values of the pairwise matrix. The resulted potential zones are classified into four categories: Poor, Moderate, Good and Very-Good, with 15.33, 70.78, 13.88 and 0.002% of the total area. Well yield data from fourteen wells are used for validation, and the accuracy value is 85.67%. HIGHLIGHTS Utilizing the Cramer’s V value for pairwise matrix enhanced the reliability of decision. The spatial variation of potential is influenced majorly by the Lithology. Annual average rainfall and groundwater fluctuation indicating the groundwater availability matches with the zones of groundwater potential.

Spatial variation in potential and realized growth of juvenile Pacific cod in the southeastern Bering Sea

Spatial variation in potential and realized growth of juvenile Pacific cod in the southeastern Bering Sea

Identification of Groundwater Potential Zones of a Tropical River Basin (Kerala, India) Using Remote Sensing and GIS Techniques

The present work accentuated the expediency of remote sensing and geographic information system (GIS) applications in groundwater studies, especially in the identification of groundwater potential zones in Ithikkara River Basin (IRB), Kerala, India. The information on geology, geomorphology, lineaments, slope and land use/land cover was gathered from Landsat ETM + data and Survey of India (SOI) toposheets of scale 1:50,000 in addition, GIS platform was used for the integration of various themes. The composite map generated was further classified according to the spatial variation of the groundwater potential. Four categories of groundwater potential zones namely poor, moderate, good and very good were identified and delineated. The hydrogeomorphological units like valley fills and alluvial plain and are potential zones for groundwater exploration and development and valley fills associated with lineaments is highly promising area for groundwater extraction. The spatial variation of the potential indicates that groundwater occurrence is controlled by geology, structures, slope and landforms.

Temporal and spatial variation in potential and realized growth rates of age‐0 year northern rock sole

The possibility of prey limitations on the growth performance of age‐0 year northern rock sole Lepidopsetta polyxystra was evaluated at three sites along the north‐east coast of Kodiak Island, Alaska, U.S.A., by comparison of observed to potential growth rates. Growth potential was measured in the laboratory across the range of temperatures encountered by this species during the first summer of life. Growth potential (gL, mm day−1) increased with water temperature (T) between 2 and 13° C, according to: gL = 0·0151 + 0·3673·log10(T). There were significant differences in growth rate between the three field sites such that Holiday Beach fish were 7·1 mm longer than Shakmanof Beach fish by mid‐September, with Pillar Creek Cove fish of intermediate size. Temperature differences between sites accounted for less than half of this variation. The remainder may have been related to differences in prey availability among the sites in association with observed differences in sediment characteristics. In addition to the spatial variability, there was significant monthly variation in growth performance. Realized growth rates between July and August were in excess of 85% of potential. Between August and September, however, realized growth fell to 43–71% of potential indicating a decline in conditions for growth. The spatial variation in growth rates was not density‐dependent as the site with the highest fish densities (Holiday Beach) also supported the highest growth rates. The available data indicates that for this subtidal species, interannual variation in growth may be more important than site variation.

Attenuation of the Electric Potential and Field in Disordered Systems

We study the electric potential and field produced by disordered distributions of charge to see why clumps of charge do not produce large potentials or fields. The question is answered by evaluating the probability distribution of the electric potential and field in a totally disordered system that is overall electroneutral. An infinite system of point charges is called totally disordered if the locations of the points and the values of the charges are random. It is called electroneutral if the mean charge is zero. In one dimension, we show that the electric field is always small, of the order of the field of a single charge, and the spatial variations in potential are what can be produced by a single charge. In two and three dimensions, the electric field in similarly disordered electroneutral systems is usually small, with small variations. Interestingly, in two and three dimensional systems, the electric potential is usually very large, even though the electric field is not: large amounts of energy are needed to put together a typical disordered configuration of charges in two and three dimensions, but not in one dimension. If the system is locally electroneutral--as well as globally electroneutral--the potential is usually small in all dimensions. The properties considered here arise from the superposition of electric fields of quasi-static distributions of charge, as in nonmetallic solids or ionic solutions. These properties are found in distributions of charge far from equilibrium.

Mining-induced seismicity in faulted geologic structures: An analysis of seismicity-induced slip potential

Relationships between the locations of mining-induced seismic events, local fault structure, and mine geometry were examined in a deep hard-rock mine in northern Idaho. Stopes experiencing rock bursts and other large seismic events were found to fall into two structural regimes: the “Silver Vein”, and the “N48°W Trend,” a steeply dipping plane of seismic activity that is subparallel to major local steeply dipping faults which bound blocky structures. The N48°W Trend also intersects a shaft that was seriously damaged when fault gouge was expelled into the opening during a 3-month period of high seismic energy release. Models of stress interaction are used to support the hypothesis that mining-induced deformation was mobilized along a 1.5 km length of the N48°W Trend. Specifically, numerical models are used to simulate rupture of seismic events and estimate induced changes in the quasi-static stress field. A Coulomb failure criterion is used with these results to estimate the spatial variation in potential for slip on planes parallel to local faulting. Increases in the potential for slip on fault planes subparallel to the N48°W Trend are consistent with activation of deformation along its 1.5 km length. For events with constant seismic moment, stress drop is shown to be far more important than source dimension in elevating slip potential along the observed plane of seismic activity

Characteristics of double layers formed by a current-drawing grid

Characteristics of double layers formed by a grid which is immersed in a large volume plasma (10 m3) are studied experimentally. Spatial variation of potential, velocity distributions of electrons and ions, fluctuation spectrum and negative resistivity and the relation between light intensity and electric potential, etc. are measured under the condition of low pressures. The argon pressure is mostly in the 10-5 torr range. The plasma density at the lower potential side is 2 to 8*106 cm-3 and the electron temperature is 2-3 eV. It is found that the plasma at the high potential side is created very efficiently by the accelerated electrons coming to both sides of the grid. Thus, the collisionless condition is well satisfied in the double layer. Discussion is made on the effect of ionization. Experimental data are compared with one-dimensional and two-dimensional collisionless theories to examine the possible parameters for the existence of double layers. Their stability against fluctuation is also studied.

The spatial variation of membrane potential near a small source of current in a spherical cell.

A theoretical analysis is presented of the change in membrane potential produced by current supplied by a microelectrode inserted just under the membrane of a spherical cell. The results of the analysis are presented in tabular and graphic form for three wave forms of current: steady, step function, and sinusoidal. As expected from physical reasoning, we find that the membrane potential is nonuniform, that there is a steep rise in membrane potential near the current microelectrode, and that this rise is of particular importance when the membrane resistance is low, or the membrane potential is changing rapidly. The effect of this steep rise in potential on the interpretation of voltage measurements from spherical cells is discussed and practical suggestions for minimizing these effects are made: in particular, it is pointed out that if the current and voltage electrodes are separated by 60 degrees , the change in membrane potential produced by application of current is close to that which would occur if there were no spatial variation of potential. We thus suggest that investigations of the electrical properties of spherical cells using two microelectrodes can best be made when the electrodes are separated by 60 degrees .

Role of Traps in a Steady-State Space Charge

Allowance for traps in certain space-charge environments produces changes in the mathematical formalism which make it difficult to determine spatial variations in potential and the negative-positive charge distribution. The trap-free model for the blocking electrode can be extended into this realm by appropriate accommodation of the equations of continuity for specified kinetics of the trap system. The tendency of traps seems to be a moderation of the spatial fall-off of potential with more gradual build-up and decay of the charge densities. The nonlinear Poisson equation has been solved analytically by the development of powerful series methods, demonstrating that machine integration can be avoided.