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In this paper we present a method using airborne laser mapping data to describe the vertical structure of a coastal mangrove forest in southeastern Florida. Mangroves are critical to coastal processes and the maintenance of vital habitats; however they are also highly threatened due to coastal development and rising sea levels. Access to mangroves for detailed ground surveys is extremely difficult due to dense vegetation and lack of stable ground in the tidal zone. Airborne laser mapping can provide accurate measurements of vegetation structure over large areas without the logistical difficulties of extensive ground surveys. In our method we derive frequency height histograms from the laser mapping data followed by the creation of image objects from areas sharing similar vertical height profiles. These image objects are classified based on their vertical height profiles and related to heights of mangrove forest communities obtained from field surveys. We show that airborne laser mapping technology can be used to classify mangrove forests and to study the spatial relationships among the different forest types.

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.

This paper describes an implementation of vertex weighting for real-time animation of 3D trees as a result of wind force and direction. This method improves over similar techniques because it incorporates individual branch animation on 3D models, whereas previous works perform animations on the model as a whole or use planar billboards to visualize the tree. Our tree animation is used in an interactive system that visualizes the effects caused by a hurricane's impact on a virtual city. The system uses models created with 3D Studio Max and the animations are implemented in OpenGL and the nVidia Cg shader language

We present a damage pattern mining framework for hurricane data on residential houses using aerial photographs with 1:3000 based scale. The vertical photographs are normally collected for an overview of a disaster area or for more detailed assessment. Damage on roof, especially for shingles torn off, is expected to be discovered in a more efficient and automatic way instead of going through the high-resolution aerial photograph for numerous details. The discovered damage patterns can then be used for hurricane damage assessment and impacts on different geographical areas. Our methodology is: (1) applying a novel and effective segmentation method on each residential house on the aerial photograph of one community, (2) using the segmentation results to obtain a set of indexing parameters for each house representing the damage level of roof cladding as well as the patterns of damage, (3) using these parameters to select several templates representing the damage patterns so that users can issue query-by-example (QBE) queries. The proposed segmentation method is an unsupervised simultaneous partition and class parameter estimation algorithm that considers the problem of segmentation as a joint estimation of the partition and class parameter variables. By utilizing this segmentation method, the indexing parameters can be obtained automatically. The QBE capability can assist in finding similar damage patterns on the roof of the residential houses in different locations in the image databases. Experiments based on the aerial photographs of Hurricane Andrew in 1992 are conducted and analyzed to show the effectiveness of the proposed hurricane damage pattern mining framework.

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).

This paper describes an approach to develop a high performance animation environment for storm surge. The system provides the capability to simulate the storm surge effects in the physical world by (1) modeling a region using the airborne light detection and ranging (LIDAR) data, USGS orthophotos, RLG road data and photos; (2) animating the storm impact by using the features of this model; and (3) providing the capability for users to explore the animation environment. We present our system by modeling the dataset collected from Ft. Lauderdale, a region in South Florida, USA.

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.

High-resolution topographic data are essential to mapping and mitigating coastal flooding and erosion hazards. The recent advent of airborne laser altimetry technology allows rapid and inexpensive topographic surveys of large coastal areas.

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 etiology of human acute myeloid leukemias (AML) remains uncertain. In order to examine the possibility of retroviral etiology in AML, we determined retroviral antigens related to HTLV-I in leukemic cell samples from 32 AML cases and peripheral blood mononuclear cells (PBMNCs) from 20 healthy donors by D-IGSS with high sensitivity and specificity, reverse transcriptase (RT) activity by a simple and sensitive non-radioisotopic RT assay, and retroviral particles by electron microscopy. The HTLV-I-related antigens were detected in 50.0% ( 16 32 ) of fresh leukemic cell samples and 87.5% ( 28 32 ) of cultured leukemic cell samples. The HTLV-I-related antigen-positive cells in fresh and cultured leukemic samples were 10.2% and 52.8%, respectively. Both frequency and level of HTLV-I-related antigens in cultured samples were much higher than in fresh samples. In contrast, no HTLV-I-related antigens were found in normal hematopoietic cells from 20 healthy donors. Further study results show that RT activity was detected not only in HTLV-I-related antigen-positive samples, but was also well correlated with the level of HTLV-I-related antigens in these samples, and preferred Mn ++ to Mg ++ as a cation. Moreover, typical retroviral particles were localized in most cultured HTLV-I-related antigen-positive samples by immunoelectron microscope. These data suggest that human acute myeloid leukemias may be etiologically associated with new human retroviral infection.

Barrier islands, the dominant geomorphic features along the U.S. Atlantic and Gulf Coasts, are a favorite place for living and visiting. Unfortunately, barrier islands are vulnerable to storm-surge flooding and erosion because of low elevations and the movement of sand by waves and tides. In order to estimate the impacts of surge flooding, sea-level rise, and erosion on barrier islands, the lengths and areas of barrier islands and population living there were quantified using high-resolution satellite imagery from Google Earth and 1990–2000 census block data. The total length and area of barrier islands spanning 18 states along the U.S. Atlantic and Gulf Coasts are about 3700 km and 6800 km2, respectively. There are approximately 1.4 million people living on barrier islands, half of which are in Florida according to 2000 census data. The population densities of barrier islands are three times those of coastal states on average, and the population increased 14% from 1990 to 2000. The collision cou...

Optical interference coatings which have been successfully used in Chinese FY-1 Meteorological Satellite and airborne remote sensing instrument are described. These include system requirements for these coatings, design approach, fabrication technique, and the actual results achieved.

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.

Our research has shown that an important relationship exists between sea level rise and sandy beach erosion. The link is highly multiplicative, with the long-term shoreline retreat rate averaging about 150 times that of sea level rise. For example, a sustained rise of 10 cm in sea level could result in 15 m of shoreline erosion. Such an amount is more than an order of magnitude greater than would be expected from a simple response to sea level rise through inundation of the shoreline. Sea level is certainly only one of many factors causing long-term beach change. Shoreline revisions from inlet dynamics and coastal engineering projects are more pronounced in most areas of the US. east coast and tend to mask the effect of a rise in sea level even over extended intervals. The implication is that sea level rise is a secondary but inexorable cause of beach erosion in such areas.

We pointed out in our paper that the two-dimensional Bruun model of beach erosion is controversial; the intensity of the controversy is amply illustrated by the responses printed in this Forum section of Eos. For example, at one end of the spectrum, Cyril Galvin derides beach erosion caused by sea-level rise as an article of faith, if not fact, while Pilkey et al. state that it is intuitive that sea-level rise is the primary factor causing shoreline retreat. Pilkey et al. assert that we erred in confining our attention to the active beach profile rather than to the much flatter coastal plain. They claim that …we should expect rates of shoreline recession 10,000 times the rate of sea-level rise through simple innundation of the shoreline. We merely point out the obvious; such dramatic beach retreat has not occurred in the last 100 years, during which relative sea level has risen 20–40 cm along the U.S. east coast. In contrast to the Pilkey et al. assertions, we know of no U.S. barrier beaches that have retreated 2,000–4,000 m in the past century; we have the historical maps, and even crude comparisons show nothing approaching this magnitude of change! Many barrier beaches (for example, Nauset Spit, Cape Cod, Massachusetts; Ocean City, Maryland) are only a thousand meters wide or less and would have long eroded away or been sitting on the mainland shore if this were even close to being true.

Coastal storms repeatedly hit the U.S. East Coast, costing many billions of dollars in losses. In 1992 Hurricane Andrew alone caused about $35–40 billion in damage. In addition to property damage, coastal storms are the major contributors to beach and dune erosion, overwash processes, and the opening of tidal inlets on barrier islands. What changes, if any, can we expect in coastal storm activity and intensity as global temperatures rise?

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