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The degradation of optical microscopic imaging is space-variant, and how to fast restore optical degraded image remains a special problem. Based on point spread function (PSF) estimation under each field of view (FOV), a L0 gradient-constrained image restoration method is proposed to solve optical degradation in microscopic imaging. Firstly, the whole scene is segmented into several different regions according to different FOV. The PSFs for each region are estimated from modulation transfer function (MTF) measured in advance. Secondly, a penalty function is designed using L0 gradient constraint to deblur the degraded images of each sub-FOV. Finally, a weighted stitching approach is used to stitch the restored images of multiple FOV (m-FOV). Experimental results indicate that the m-FOV analysis could well solve the problem of space-variant degradation. Compared with the other methods, both subjective and objective evaluation results prove that the L0 norm idea could rapidly and effectively restore the degraded image. The approach could be well applied to a real product.

Blue carbon ecosystems (BCEs) provide many ecosystem services as “the benefits people obtain from ecosystems.” These include important recreational and tourism opportunities, key fishery habitat, water quality improvements, and flood and erosion mitigation. These are co-benefits of BCEs in addition to carbon sequestration. The monetary value of these services are best known for coastal protection and carbon sequestration, with monetary value of coastal protection services estimated at \23 billion year− 1 between 1980 and 2008.

Kelly et al. (Coast Eng J 57(4):1–30, 2015) present a finite volume dynamic adaptive mesh model based on Osher’s approximate Riemann solver for the prediction of storm surges over complex landscapes. Here, the model described in that paper is extended to use distributed memory parallel block tree-based mesh refinement via the PARAMESH library. The resulting model, called the fully adaptive storm tide (FAST) model, can thus be run on massively parallel supercomputers. In this paper, we validate the FAST model by conducting numerical simulations of the storm surges due to hurricanes Wilma (2005) on Lake Okeechobee and Ike (2008) in the Gulf of Mexico. The storm surge due to Wilma on Lake Okeechobee is interesting as it can be considered as an almost idealized case which comprises a closed system. The case of hurricane Ike is more complex as it involves a coastline and additional features such as barrier islands and tidally controlled boundaries. For both cases, results obtained using the FAST model compare favorably with the measured water elevation and high-water mark data. Moreover, we show that, with sufficient computational resource, low runtimes are possible for real-world surge simulations. The FAST model therefore has the potential to run the ensemble predictions necessary to account for the variability that is inherent in hurricane forecasting.

The geographic area that the Joint Airborne LiDAR Bathymetry Technical Center of Expertise (JALBTCX) covers with their Light Detection and Ranging (LiDAR) program allows for researchers to quantify coastal metrics on national, regional and local scales. As these studies progressed, it has become apparent that software needs to be developed to quantify coastal change from LiDAR at multiple scales. The purpose of this research is to provide coastal managers with quantities and locations of change that occurred on eastern US coastlines, and if the researcher would like additional information, provide the tools necessary for additional metrics to be quantified and additional questions to be answered.

The operational forecast demands and constraints of the National Hurricane Center require that a storm surge model in research mode be tested against a benchmark model such as Sea, Lake, and Overland Surges from Hurricanes (SLOSH) for accuracy, computation time, and numerical stability before the model is used for operational forecasts. Additionally, the simulated results must be in a geographic information system format to facilitate the usage of computed storm surge for various applications. This paper presents results from a demonstration project to explore the pathway for the transition of the Coastal and Estuarine Storm Tide (CEST) model to an operational forecast model by testing CEST over SLOSH basins in Florida. The performance and stability of CEST were examined by conducting simulations for Hurricane Andrew (1992) and more than 100 000 synthetic hurricanes for nine SLOSH basins covering the Florida coast and Lake Okeechobee. The results show that CEST produces peak surge heights similar to those from SLOSH. Additionally, CEST has proven to be numerically stable against all synthetic hurricanes and the computation time of CEST is comparable to that of SLOSH. Therefore, CEST has the potential to be used for operational forecasts of storm surge. The potential of producing more detailed real-time surge inundation forecasts was also investigated through the simulations of Andrew's surge on various grids with different cell sizes. The results indicate that CEST can produce 48-h forecasts using a single processor in about 40 min over a grid generated by reducing the cell edge size of the SLOSH grid by 4 times.

The potential impacts of sea level rise (SLR) on 95% of the land areas of the Florida Keys were estimated through analysis of a digital elevation model (DEM) derived from airborne light detection and ranging (LiDAR) measurements in a geographic information system. The topographic detail of the LiDAR DEM allowed projections of land, population, and property inundation in 0.15 m increments across a broad range of SLR scenarios for the next century. The results showed that a 0.6 m SLR by 2100 would inundate about 70% of the total land surface, but smaller percentages of the population (17%) and real property (12%). A 1.5 m rise in sea level during the same period would inundate 91% of the land surface, 71% of the population and 68% of property in the study area. Comparison of inundation dynamics indicates that the Lower Florida Keys are more susceptible to SLR than the Upper Florida Keys. The inundation dynamics exhibit non-linear behavior and demonstrate tipping points in inundation processes beyond which the inundation of land, population, and property speeds up. Acceleration of SLR will amplify the non- linear inundation, causing tipping points to be reached sooner.

Sea-level rise presents an imminent threat to freshwater-dependent ecosystems on small oceanic islands, which often harbor rare and endemic taxa. Conservation of these assemblages is complicated by feedbacks between sea level and recurring pulse disturbances (eg hurricanes, fire). Once sea level reaches a critical level, the transition from a landscape characterized by mesophytic upland forests and freshwater wetlands to one dominated by mangroves can occur suddenly, following a single storm-surge event. We document such a trajectory, unfolding today in the Florida Keys. With sea level projected to rise substantially during the next century, ex-situ actions may be needed to conserve individual species of special concern. However, within existing public conservation units, managers have a responsibility to conserve extant biodiversity. We propose a strategy that combines the identification and intensive management of the most defensible core sites within a broader reserve system, in which refugia for biota facing local extirpation may be sought.

This paper presents a framework that applies a series of algorithms to automatically extract building footprints from airborne light detection and ranging (LIDAR) measurements. In the proposed framework, the ground and nonground LIDAR measurements are first separated using a progressive morphological filter. Then, building measurements are identified from nonground measurements using a region-growing algorithm based on the plane-fitting technique. Finally, raw footprints for segmented building measurements are derived by connecting boundary points, and the raw footprints are further simplified and adjusted to remove noise caused by irregularly spaced LIDAR measurements. Data sets from urbanized areas including large institutional, commercial, and small residential buildings were employed to test the proposed framework. A quantitative analysis showed that the total of omission and commission errors for extracted footprints for both institutional and residential areas was about 12%. The results demonstrated that the proposed framework identified building footprints well

Three-dimensional computer visualization and animation can provide a substitute for coastal residents', lack of personal experience with hurricane-surge flooding. Tremendous progress has been made in 3D animation in the last decade, which movies such as Perfect Storm and The Day After Tomorrow have demonstrated. However, the 3D visualization and animation system for storm-surge flooding differs from those in Hollywood movies in three aspects. First, objects such as buildings, roads, and trees in a synthetic 3D visualization environment not only have to be able to duplicate the real-world feature visually, but also be georeferenced so users can find real locations through addresses or spatial coordinates. The sizes and shapes of buildings and trees have to be accurate so users can sense the severity of flooding by comparing the water level with heights of familiar objects. Second, the magnitude, extent, and process of storm-surge flooding have to be accurate enough to represent the real situation. This information has to be based on hydrodynamics of storm surge. Third, the damage extent of a property caused by storm surge and waves, such as the collapse of a house, must be determined by engineering rules. Recent advances in high-resolution remote-sensing technology and numerical modeling make it possible to provide accurate data for the earth's surface features and storm-surge flooding.

This paper examines the feasibility of using LIDAR surveys to update existing historical shoreline data sets by comparing contour shorelines and the high water line (HWL) at eight study locations in North and South Carolina. The analysis was based on airborne LIDAR topography and orthoimagery collected simultaneously during June 2000. The popular method of digitizing the wet-dry line from orthoimagery was used to measure the HWL. Contour shorelines were derived by using the previous high tide (HW), the mean high water datum (MHW), and the mean higher high water datum (MHHW) of nearby tide gauges. A method was developed to quantitatively compare the positions of the HWL and the contour shorelines in a GIS. The mean high water and mean higher high water contour shoreline positions were the best match to the high water line at 7 of 8 locations, and differed by less than 5.4 meters from the digitized high water line positions. This difference is well within the errors associated with past methods for measuring shoreline position. Therefore, it is deemed practical to use LIDAR data to estimate the HWL.

High quality DEM (Digital Elevation Model) is indispensable for a smart city nowadays. A large quantity of useful spatial information can be extracted from the big data acquired by surveying, imaging, and even mobile device with GPS system. This information is critical to many applications such as urban management, emergency event planning, and social location services. The extraction of non-ground features such as buildings, constructions and vegetation can be used to generate accurate boundary shape and three dimensional models. These outcomes can be utilized to provide useful information for the location service for mobile social networks. The DEM can be generated by surveying the area. LIDAR (Light Detection and Ranging) is a widely used remote sensing technology to survey the urban area. High resolution three dimensional data can be acquired from the LIDAR survey. How to separate the terrain surface and non-terrain features from three dimensional spatial data is the most challenging task for generating high quality DEM. In this paper, a multi-pass morphological filter is proposed to generate better DEMs on complex urban areas that have difficulties to use large filtering window sizes. Multi-pass filtering will use relatively small filtering window sizes in multiple rounds to avoid the cut-off problem commonly present when large window sizes are used in filtering. A priority boundary interpolation method is proposed and dedicated to interpolate the intermediate filtering result between each pass. A second pass of the morphological filter will use filtering window sizes in descending order to remove the remaining areas from large non-ground objects that cannot be removed with small window sizes. The filtering results demonstrate that the proposed method is able to effectively use relatively small filtering windows to filter large non-ground objects on complex terrains and avoid the cut-off problem.

This paper presents a Graphical User Interface (GUI) system to process huge volume geospatial data acquired from LIDAR survey. This GUI system provides friendly user interface to display, edit and process LIDAR data. It also offers useful geospatial tool kits to process area of interest from a big data set. The processing results would be used for high quality digital elevation model (DEM) generation and mapping.

LIDAR (Light Detection and Ranging) is a widely used technology to measure terrain properties and topographic mapping nowadays. Many filtering methods have been developed to process the geospatial data generated by LIDAR to generate bare earth digital terrain models. Among these methods, mathematical morphological filtering is a very effective and efficient method to separate ground and non-ground objects from LIDAR data. This method can achieve ideal results in the flat terrain, while it is not working very well in the undulating and complex terrain with large non-ground objects. The reason is that it would remove ground terrain objects along with filtering large size non-ground objects when using a large filtering window size. Especially in the mountainous terrain, it would cause the hill cut-off problem, which is a common problem for morphological filters. In this paper, a cluster-based morphological filter is proposed to improve the progressive morphological filter and make it work better on more undulating and complex terrain types. The filtering results demonstrate that the proposed method is able to effectively preserve terrain ground objects and remove large non-ground objects.

Using plasma assisted pulsed DC magnetron sputtering technology, low loss, high performance optical coatings have been achieved. Coating examples using Ta2O5 and SiO2 materials are demonstrated. This technology is suitable for volume production.

The rise of offshore water caused by the high winds of a low pressure weather system, or storm surge, is a hurricane's greatest threat to human life. As weather forecasters struggle to enable coastal residents to make timely evacuation decisions, the need arises for more visually compelling and interactive storm surge visualization tools. This paper presents an interactive and three-dimensional storm surge visualization system. It integrates road, topographic, and building data to construct accurate three-dimensional models of major cities in the State of Florida. Storm surge data are then used to construct a three-dimensional ocean positioned over the terrain models. Ambient details such as wind, vegetation, ocean waves, and traffic are animated based on up-to-date wind and storm surge data. Videos of the storm surge visualizations are recorded and made available to coastal residents through a web-interface. The three-dimensional visualization of geographic and storm surge data provides a more visually compelling representation of the potential effects of storm surge than traditional two-dimensional models and is more capable to enable coastal residents to make potentially life-saving evacuation decisions.

A framework which includes six major components has been developed to reconstruct 3D building models from airborne LiDAR measurements. The application of the framework to both commercial and adjacent residential areas shows that the proposed methods identified building patches well, and reconstructed 3D building models effectively. The entire process is highly automatic and requires little human aid, which is very useful for processing voluminous LIDAR measurements.

A polarization insensitive, low wavefront distortion 50% beamsplitter is presented. 0.2% split of s and p polarization from 1540nm to 1575nm and less than 1/30th waves peak to valley surface error at 632.8nm were achieved.

We report the most recent advances of optical beamsplitters for laser communications developed at Barr Associates. The challenges for meeting the two key requirements, polarization control and wavefront control, of the lasercom beamsplitters are discussed. It is demonstrated that in order to meet the two key requirements, the repeatability of the refractive indices and the thickness of the coatings need to be controlled within 0.3% and 0.1% respectively from run to run, and the coating stress need to be controlled to less than 25 MPa. The latest result of various lasercom beamsplitters will be presented. For a typical 50% reflection and 50% transmission beamsplitter at 22.5 degree angle of incidence, the s and p polarization split is less than 0.2% from 1540nm to 1575nm and the surface flatness of the beamsplitter after coating is less than 1/40 th waves peak to valley at 632.8nm.

Barrier beaches along the U.S. East and Gulf Coasts are some of the most popular recreational areas and most expensive real estate in the United States. For those people who take vacations, more than 70 percent will visit a beach (www.aaa.com). According to insurance industry reports, there is more than $3.1 trillion at risk to coastal storms (Institute for Business and Home Safety).

Theoretical analysis is made for thin-film-based, 200- and 100-GHz narrow bandpass filters with respect to the intensity response as well as to the chromatic dispersion. The results indicate that the narrower the passband, the higher the chromatic dispersion. The maximum chromatic dispersion appears at the edges of the 0.5-dB passband, owing to the fast change of the group delay in the region. The deviation of chromatic dispersion induced by manufacturing error is simulated. Effective-medium approximation layers are added to simulate the contribution of surface roughness and the mixture interfaces to the passband ripple as well as the chromatic dispersion. The simulations are compared with the experimental results. The measured chromatic dispersion matches the general trend of the theoretical calculation. The imperfect surface and layer mismatch induce additional ripples across the 0.5-dB passband. The maximum chromatic dispersion within a 0.5-dB passband is 20.7 and 54.9 ps/nm for 200- and 100-GHZ narrow bandpass filters, respectively.

The scattering behavior for narrow band pass filters processed by ion beam sputtering was evaluated and compared to that of a Corning proprietary process. Results showed no significant difference in scattering for the different processes.

The chromatic dispersion of narrow bandpass filters for DWDM application is discussed. Theoretical simulations are compared with the experimental results; the deviation of chromatic dispersion induced by manufacturing error is simulated.

The success of volume production of 200GHz and 100GHz spacing WDM band pass filters relies on several critical issues: (a) a robust, high tolerance design; (b) optimized machine configurations; (c) a stable and repeatable process; and (d) an accurate and reliable optical monitoring system. At Corning NetOptix, significant effort has been made to optimize the chamber and process parameters in order to control the optical performance, the reproducibility and the useful area. This results in increased production yields and excellent filter performance. The results of 200GHz and 100GHz spacing WDM filters manufactured at Corning NetOptix are presented.

The optical and semiconductor properties of lead telluride coatings are dependent on various factors contributing to its performance. In this paper, we will present the temperature dependent effects of single layer lead telluride coatings on the dispersion and absorption characteristics, absorption edge, and carrier concentration from 15 K to 436 K using both experimental and theoretical analysis.

Special problems that influence the accuracy of controlling the optical thickness of infrared coatings during deposition are discussed.