Review paper Weymer et al.: statistical modeling of the long-range dependent structure of barrier island framework geology and surface geomorphology

2018 ◽  
Author(s):  
Anonymous
Keyword(s):  
Statistical Modeling ◽  
Long Range ◽  
Review Paper ◽  
Barrier Island ◽  
Surface Geomorphology

scholarly journals Long-range dependence in coastal framework geology: Asymmetries and implications for barrier island resiliency

2018 ◽  
Author(s):  
Phillipe Wernette ◽  
Chris Houser ◽  
Bradley Weymer ◽  
Mark Everett ◽  
Michael Bishop ◽  
...  
Keyword(s):  
Long Range ◽  
Coastal Management ◽  
Moving Average ◽  
Barrier Island ◽  
Long Range Dependence ◽  
The North ◽  
Arfima Models ◽  
Societal Pressure ◽  
Dune Morphology

Abstract. Barrier island transgression is influenced by the alongshore variation in beach and dune morphology, which determines the amount of sediment moved landward through washover. While several studies have demonstrated how variations in dune morphology affect island response to storms, the reasons for that variation and the implications for island management remain unclear. This paper builds on previous research by demonstrating that the framework geology can influence beach and dune morphology asymmetrically alongshore. The influence of relict paleo-channels on beach and dune morphology on Padre Island National Seashore, Texas was quantified by isolating the long-range dependence (LRD) parameter in autoregressive fractionally-integrated moving average (ARFIMA) models. ARFIMA models were fit across all scales and a moving window approach was used to examine how LRD varied with computational scale and location along the island. The resulting LRD matrices were plotted by latitude to place the results in context of previously identified variations in the framework geology. Results indicate that the LRD is not constant alongshore for all surface morphometrics. Many flares in the LRD plots correlate to relict infilled paleo-channels in the framework geology, indicating that the framework geology has a significant influence on the morphology of PAIS. Barrier island surface morphology LRD is strongest at large paleo-channels and decreases to the north. The spatial patterns in LRD surface morphometrics and framework geology variations demonstrate that the influence of paleo-channels in the framework geology can be asymmetric where the alongshore sediment transport gradient was unidirectional during island development. The asymmetric influence of framework geology on coastal morphology has long-term implications for coastal management activities because it dictates the long-term behavior of a barrier island. Coastal management projects should first seek to understand how the framework geology influences coastal processes in order to more effectively balance long-term natural variability with short-term societal pressure.

scholarly journals Statistical modeling of the long-range-dependent structure of barrier island framework geology and surface geomorphology

2018 ◽  
Vol 6 (2) ◽  
pp. 431-450 ◽  
Author(s):  
Bradley A. Weymer ◽  
Phillipe Wernette ◽  
Mark E. Everett ◽  
Chris Houser
Keyword(s):  
Sea Level Rise ◽  
Sea Level ◽  
Long Range ◽  
Moving Average ◽  
Quantitative Measure ◽  
Barrier Island ◽  
Barrier Islands ◽  
Wave Number ◽  
Statistical Parameters ◽  
Padre Island

Abstract. Shorelines exhibit long-range dependence (LRD) and have been shown in some environments to be described in the wave number domain by a power-law characteristic of scale independence. Recent evidence suggests that the geomorphology of barrier islands can, however, exhibit scale dependence as a result of systematic variations in the underlying framework geology. The LRD of framework geology, which influences island geomorphology and its response to storms and sea level rise, has not been previously examined. Electromagnetic induction (EMI) surveys conducted along Padre Island National Seashore (PAIS), Texas, United States, reveal that the EMI apparent conductivity (σa) signal and, by inference, the framework geology exhibits LRD at scales of up to 101 to 102 km. Our study demonstrates the utility of describing EMI σa and lidar spatial series by a fractional autoregressive integrated moving average (ARIMA) process that specifically models LRD. This method offers a robust and compact way of quantifying the geological variations along a barrier island shoreline using three statistical parameters (p, d, q). We discuss how ARIMA models that use a single parameter d provide a quantitative measure for determining free and forced barrier island evolutionary behavior across different scales. Statistical analyses at regional, intermediate, and local scales suggest that the geologic framework within an area of paleo-channels exhibits a first-order control on dune height. The exchange of sediment amongst nearshore, beach, and dune in areas outside this region are scale independent, implying that barrier islands like PAIS exhibit a combination of free and forced behaviors that affect the response of the island to sea level rise.

scholarly journals Statistical modeling of the long-range dependent structure of barrier island framework geology and surface geomorphology

2018 ◽  
Author(s):  
Bradley A. Weymer ◽  
Phillipe Wernette ◽  
Mark E. Everett ◽  
Chris Houser
Keyword(s):  
Sea Level Rise ◽  
Sea Level ◽  
Long Range ◽  
Moving Average ◽  
Quantitative Measure ◽  
Barrier Island ◽  
Barrier Islands ◽  
Auto Regressive ◽  
Padre Island ◽  
Dune Height

Abstract. Shorelines exhibit long-range dependence (LRD) and have been shown in some environments to be described in the wavenumber domain by a power law characteristic of scale-independence. Recent evidence suggests that the geomorphology of barrier islands can, however, exhibit scale dependence as a result of systematic variations of the underlying framework geology. The LRD of framework geology, which influences island geomorphology and its response to storms and sea level rise, has not been previously examined. Electromagnetic induction (EMI) surveys conducted along Padre Island National Seashore (PAIS), Texas, USA, reveal that the EMI apparent conductivity σa signal and, by inference, the framework geology exhibits LRD at scales up to 101 to 102 km. Our study demonstrates the utility of describing EMI σa and LiDAR spatial series by a fractional auto-regressive integrated moving average process that specifically models LRD. This method offers a robust and compact way for quantifying the geological variations along a barrier island shoreline using three parameters (p,d,q). We discuss how ARIMA (0,d,0) models that use a single parameter d provide a quantitative measure for determining free and forced barrier island evolutionary behavior across different scales. Statistical analyses at regional, intermediate, and local scales suggest that the geologic framework within an area of paleo-channels exhibits a first order control on dune height. The exchange of sediment amongst nearshore, beach and dune in areas outside this region are scale-independent, implying that barrier islands like PAIS exhibit a combination of free and forced behaviors that affect the response of the island to sea level rise.

scholarly journals A Review Paper on Advance Long Range Spy Robot

2021 ◽  
Vol 9 (VI) ◽  
pp. 2817-2819
Author(s):  
Sanket Gawande
Keyword(s):  
Long Range ◽  
Mobile Application ◽  
Review Paper ◽  
Night Vision ◽  
Metal Detection ◽  
Forest Regions ◽  
Illegal Activities

Now a day many illegal activities like crossing borders through forest regions, planting landmines, etc to keep an eye on such activities there is a need for some spying device that can spy on the restricted areas or some forest or territorial region where a human cannot go due to risk. In this paper, we have described such type of spy robot that is ‘long range spy robot with night vision camera’. This system Long Range Spy Robot with Metal Detection is very innovative as this system allows operating a robot irrespective of the distance. To drive the system, the user has to formulate a call to the phone coupled to this robot and once the call is received, the user will have to make use of the keypad to transmit data commands to the robot. The data commands will make the robot either go in forward, then backward, left, or right direction. The system makes use of a night vision-enabled spy vision-enabled help of which the user can view the area captured by this spy camera which will be mounted on this robot. The user will be able to view the area captured by this spy camera not only during the daytime but also during the night. All the areas captured by this spy camera can be viewed in a mobile application or PC.

Statistics and parallaxes

1978 ◽  
Vol 48 ◽  
pp. 7-29
Author(s):  
T. E. Lutz
Keyword(s):  
Experimental Design ◽  
Statistical Methods ◽  
Review Paper ◽  
Systematic Errors ◽  
Past Experience ◽  
Random Errors ◽  
Trigonometric Parallaxes ◽  
Systematic And Random Errors

This review paper deals with the use of statistical methods to evaluate systematic and random errors associated with trigonometric parallaxes. First, systematic errors which arise when using trigonometric parallaxes to calibrate luminosity systems are discussed. Next, determination of the external errors of parallax measurement are reviewed. Observatory corrections are discussed. Schilt’s point, that as the causes of these systematic differences between observatories are not known the computed corrections can not be applied appropriately, is emphasized. However, modern parallax work is sufficiently accurate that it is necessary to determine observatory corrections if full use is to be made of the potential precision of the data. To this end, it is suggested that a prior experimental design is required. Past experience has shown that accidental overlap of observing programs will not suffice to determine observatory corrections which are meaningful.

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