Morphodynamics of headland-bay beaches: Examples from the Coast of Santa Catarina state, Brazil

The overall goal of this study is to contribute to increased understanding of headland-bay beach morphodynamics, z'.e to elucidate the interaction between hydrodynarnic processes, beach morphology and sedimentology at Large Scale Coastal Behaviour in the c oastline o f S anta C atarina, b etween L aguna and S ão Francisco, an east coast swell enviromnent with headland and bay geomorphologies. In order to investigate morphodynamic processes, beach planforms for 90 beaches on the Santa Catarina coast were analyzed by utilizing maps and aerial photography at different scales. An intensive field investigation of m orphologic and sedimentological changes was conducted on 28 beaches in central-north Santa Catarina coast from May 1994 to March 1996, where morphological and sedimentological changes were related to spatial variations in wave/tidal and sedimentary provenance conditions. Field investigations were additionally conducted on three beaches in an effort to determine alongshore sediment mobility at headland-bay beaches. In this case, temporal morphological changes were correlated with wave information (wave height, period and direction obtained from visual beach observations and wave forecast models).O objetivo principal deste estudo é contribuir para o aumento do entendimento da morfodinâmica de praias de enseada, isto é, elucidar a interação entre processos hidrodinâmicos, morfologia e sedimentologia praial em meso e macro escala. A área de estudo compreende as praias do estado de Santa Catarina, entre Laguna e São Francisco, as quais se encontram em uma zona costeira que recebe ondulações provenientes de leste e apresenta uma geomorfologia composta de promontórios e baias. Para a definir a forma em planta, 90 praias forarn analisadas utilizando-se de mapas e fotografia aéreas em diferentes escalas. Um programa intensivo de levantamento de campo das mudanças morfológicas e sedimentológicas foi conduzido em 28 praias no litoral centro-norte de Santa Catarina, entre Maio de 1994 e Março de 1996. As mudanças morfológicas e sedimentológicas foram relacionadas com variações espaciais nas condições das ondas/marés, bem como proveniência dos sedimentos. Adicionalmente, foram conduzidos levantamentos morfológicos em três praias (Praia Brava, Balneário Camboriú e Taquaras/Taquarinhas) para determinar-se o transporte de sedimento ao longo da costa em praias de enseada. Neste caso, as variações morfológicas foram relacionadas com observações visuais e previsões de ondas

Aeronautical Engineering: A Continuing Bibliography

This bibliography lists reports, articles and other documents announced in the NASA science and technical information system. Subject coverage includes: Design, construction and testing of aircraft and aircraft engines; aircraft components, equipment and systems; ground support systems; and theoretical and applied aspects of aerodynamics and general fluid dynamics

Pressure measurement in wood as a method to understand impregnation processes : conventional and supercritical carbon dioxide

Two approaches to improving wood treatability include the modification of pressure schedules during conventional liquid treatments and the use of supercritical fluids (SCFs). In both of these techniques, pressure differences are important for transporting materials into wood. The level of pressure and its change during SCF treatments are also important for controlling the solubility of these materials. Empirical pressure measurements may be used to explain minimal or inconsistent improvements resulting from pressure schedule modifications during conventional liquid treatments and the non-uniform distribution of deposited materials and wood defects that have resulted from SCF treatments. This investigation provided empirical data on pressure development in wood during pressure processes. Measurement techniques were developed and evaluated during conventional and supercritical carbon dioxide (SC-CO₂) treatments. A technique using probes epoxied into samples and then drilled open at the probe tips was the simplest and most effective method for assessing pressure. However, the hydraulic fluid used to transfer pressure from samples to sensors interfered with measurements during the venting phase of SC-CO₂ treatments. The effects of process parameters and wood characteristics on internal pressure development were investigated by making internal pressure measurements under different treatment conditions. Qualitative comparisons between treatments were made using pressure response quantifiers derived from the pressure measurements. Results from conventional liquid treatments indicated that minor changes in pressure schedules are not derived from the pressure measurements. Results from conventional liquid treatments indicated that minor changes in pressure schedules are not likely to enhance the treatability of wood. Results from SC-CO₂ treatments indicated differing pressure response delays with different pressing and venting rates, wood species, and grain orientations. These delays resulted in surface-to-center pressure differences which could be used to explain preservative retention distribution, wood collapse and fracture, and wood dimensional changes observed by other investigators. Finally, a preliminary investigation showed that average air permeability and anatomical measurements were poorly correlated with pressure response quantifiers from SC-CO₂ treatments when pooled for eight softwood and three hardwood species. The pooled results for softwoods suggested that only resin canal dimensions were correlated with pressure response quantifiers

Lunar deep drill apparatus

A self contained, mobile drilling and coring system was designed to operate on the Lunar surface and be controlled remotely from earth. The system uses SKITTER (Spatial Kinematic Inertial Translatory Tripod Extremity Robot) as its foundation and produces Lunar core samples two meters long and fifty millimeters in diameter. The drill bit used for this is composed of 30 per carat diamonds in a sintered tungsten carbide matrix. To drill up to 50 m depths, the bit assembly will be attached to a drill string made from 2 m rods which will be carried in racks on SKITTER. Rotary power for drilling will be supplied by a Curvo-Synchronous motor. SKITTER is to support this system through a hexagonal shaped structure which will contain the drill motor and the power supply. A micro-coring drill will be used to remove a preliminary sample 5 mm in diameter and 20 mm long from the side of the core. This whole system is to be controlled from earth. This is carried out by a continuously monitoring PLC onboard the drill rig. A touch screen control console allows the operator on earth to monitor the progress of the operation and intervene if necessary

Bibliography of NASA published reports on general aviation, 1975 to 1981

This bibliography lists 478 documents which relate to all heavier-than-air fixed wing aircraft exclusive of military types and those used for commercial air transport. An exception is the inclusion of commuter transport aircraft types within the general aviation category. NASA publications included in this bibliography are: conference publications (CP), reference publications (RP), technical memorandums (TM, TMX), technical notes (TN), technical papers (TP), and contractor reports (CR). In addition, papers and articles on NASA general aviation programs published by technical societies (AIAA, SAE, etc.) are included, as well as those listed in NASA's Scientific and Technical Aerospace Reports (STAR) Journal. Author and subject indexes are also provided to facilitate use of the bibliography

Upgrading Safety Performance in Retrofitting Traffic Railing Systems

DOT-FH-11-8100From bridge rail information of 51 State highway agencies and personal interviews with five selected highway agencies, current state-of-the-art of bridge railing safety performance was assessed. Based on the analysis of 14 specific railing designs, an estimated assessment of the performance of bridge rails on a national scale is presented. The data indicates that a significant percentage of existing railings may be below currently attainable safety performance standards. Bridge railing designs are grouped into four categories according to profile geometry and features that are amenable to a common retrofit design. Two categories, II and III, represent about 82 percent of existing installations. Five retrofit designs for Categories II and III were developed and evaluated by a 22-crash test program. Although not crash-test evaluated, an improved approach guardrail design features a thrie beam rail element and a breakaway cable terminal

The Pan American (1985-02)

https://scholarworks.utrgv.edu/panamerican/1469/thumbnail.jp

Flight Mechanics/Estimation Theory Symposium, 1994

This conference publication includes 41 papers and abstracts presented at the Flight Mechanics/Estimation Theory Symposium on May 17-19, 1994. Sponsored by the Flight Dynamics Division of Goddard Space Flight Center, this symposium featured technical papers on a wide range of issues related to orbit-attitude prediction, determination and control; attitude sensor calibration; attitude determination error analysis; attitude dynamics; and orbit decay and maneuver strategy. Government, industry, and the academic community participated in the preparation and presentation of these papers