Correlation of forebody pressures and aircraft yawing moments on the X-29A aircraft at high angles of attack

In-flight pressure distributions at four fuselage stations on the forebody of the X-29A aircraft have been reported at angles of attack from 15 to 66 deg and at Mach numbers from 0.22 to 0.60. At angles of attack of 20 deg and higher, vortices shed from the nose strake caused suction peaks in the pressure distributions that generally increased in magnitude with angle of attack. Above 30 deg-angle of attack, the forebody pressure distributions became asymmetrical at the most forward station, while they remained nearly symmetrical until 50 to 55 deg-angle of attack for the aft stations. Between 59 to 66 deg-angle of attack, the asymmetry of the pressure distributions changed direction. Yawing moments for the forebody alone were obtained by integrating the forebody pressure distributions. At 45 deg-angle of attack, the aircraft yaws to the right and at 50 deg and higher, the aircraft yaws to the left. The forebody yawing moments correlated well with the aircraft left yawing moment at an angle of attack of 50 deg or higher. At a 45 deg-angle of attack, the forebody yawing moments did not correlate well with the aircraft yawing moment, but it is suggested that this was due to asymmetric pressures on the cockpit region of the fuselage which was not instrumented. The forebody was also shown to provide a positive component of directional stability of the aircraft at angles of attack of 25 deg or higher. A Mach number effect was noted at angles of attack of 30 deg or higher at the station where the nose strake was present. At this station, the suction peaks in the pressure distributions at the highest Mach number were reduced and much more symmetrical as compared to the lower Mach number pressure distributions

Settlement of the Acorn Barnacle Balanus From Mobile Bay and Weeks Bay, Alabama

Barnacle cyprids and metamorphosed settlers were collected using glass slides as artificial substrates at six sites in the Mobile Bay area. Three sites were located in Weeks Bay, Alabama, where the highest settlement concentration occurred near the entrance to Mobile Bay. Two sites in the north end of Weeks Bay near the Fish River had very reduced settlement. The remaining three locations were on the north shore of Dauphin Island, Alabama. Settlement at Dauphin Island was most abundant at the deeper of two sites at the Dauphin Island Sea Lab boat dock, possibly because the substrates were exposed to less wave action. The other two sites at Dauphin Island were shallow and relatively unsettled when compared with the deep site. Adult barnacles recovered from the Weeks Bay and Dauphin Island locations include Balanus eburneus, B. venustus, B. improvisus, and B. subalbidus. Our data indicate two primary settlement periods for these species, late winter to spring and late summer to fall, with the highest settlement occurring in Feb. and March

Ciliated Protozoan Colonization of Substrates From Weeks Bay, Alabama

Ciliated protozoan colonization of artificial substrates was examined during a 12-mo period from Jan. to Dec. 2001 in Weeks Bay, Alabama. Artificial substrates (glass slides) were suspended in the water at three locations in the Bay for a period of I wk/mo, and the population density of the stalked peritrich Vorticella was determined. Environmental data collected during the colonization period were compared with the population results. There was a positive correlation between colonization and water temperature at two sites and between phosphate and colonization at one site. Additionally, a negative correlation was determined between colonization and dissolved oxygen at two sites, between colonization and nitrate at one site, and between colonization and pH at one site. The protozoan assemblage varied from month to month, although the overall dominance of Vorticella was maintained. Although the size of the population of Vorticella is likely influenced by a number of different variables, we believe that temperature and bacterial abundance are the likely controlling factors

A database management capability for Ada

The data requirements of mission critical defense systems have been increasing dramatically. Command and control, intelligence, logistics, and even weapons systems are being required to integrate, process, and share ever increasing volumes of information. To meet this need, systems are now being specified that incorporate data base management subsystems for handling storage and retrieval of information. It is expected that a large number of the next generation of mission critical systems will contain embedded data base management systems. Since the use of Ada has been mandated for most of these systems, it is important to address the issues of providing data base management capabilities that can be closely coupled with Ada. A comprehensive distributed data base management project has been investigated. The key deliverables of this project are three closely related prototype systems implemented in Ada. These three systems are discussed

Bacterial Communities on the Northern Gulf of Mexico Continental Shelf are Influenced by Sediment Characteristics Affected by the Mississippi River

Benthic bacteria in the Gulf of Mexico serve the base of the sediment food chain as a food source for various marine organisms. In this paper, we analyzed the bacterial community and sediment characteristics from 14 sediment samples collected along the continental shelf of the northern Gulf of Mexico. Using the bacterial community to assess relationships among our sites, the data revealed groupings of sites that correlated to the sediment characteristics, generally grouped as western sites in Louisiana near the outflow of the Mississippi River and eastern Florida sites more distant from the outflow. Cluster analysis and multidimensional scaling demonstrated significant groupings of Louisiana vs Florida bacterial communities, and distance-based redundancy analysis related these groupings to sediment characteristics. Given the directions of currents around the Mississippi River, our data suggested that the outflow of the river is a major factor affecting the benthic bacterial community in the northern Gulf of Mexico

Variations in the Ventral Ciliature of the Crustacean Symbiont Hyalophysa (Ciliophora, Apostomatida) from Mobile Bay and Dauphin Island, Alabama

Apostome ciliates are symbiotic organisms whose life cycles are complex and involve specific feeding, divisional, migratory, and phoretic stages. In this study we examined apostome trophonts (the diagnostic stage) from a variety of crustacean hosts in the Mobile Bay and Dauphin Island, Alabama, area. The hosts were grass shrimp (Palaemonetes pugio and P. paludosus), striped hermit crab (Clibanarius vittatus), blue crab (Callinectes sapidus), and pink shrimp (Farfantepenaeus (=Penaeus) duorarum). A number of similar but distinct morphotypes of apostomes were present, those corresponding to descriptions of species of Hyalophysa as well as variant forms. The morphotypes observed in this study had the following characteristics: variations in the formation of the anterior ventral field of kinetosomes from falciform field 9; variations in the degree to which ciliary row 1 (kinety 1) was separated into 2 segments; and variations in the development of kinety a. A record of the variant morphotypes that do not correspond exactly to an established species should prove useful to biologists attempting to identify apostomes from crustacean molts. We choose not to name the variant forms as new species because they exist as different morphotypes within a population of cells, because some of these types occur in low frequency, and because one of the variant forms changes from one morphotype to another

Variations in the Ventral Ciliature of the Crustacean Symbiont Hyalophysa (Ciliophora, Apostomatida) from Mobile Bay and Dauphin Island, Alabama

Apostome ciliates are symbiotic organisms whose life cycles are complex and involve specific feeding, divisional, migratory, and phoretic stages. In this study we examined apostome trophonts (the diagnostic stage) from a variety of crustacean hosts in the Mobile Bay and Dauphin Island, Alabama, area. The hosts were grass shrimp (Palaemonetes pugio and P. paludosus), striped hermit crab (Clibanarius vittatus), blue crab (Callinectes sapidus), and pink shrimp (Farfantepenaeus (=Penaeus) duorarum). A number of similar but distinct morphotypes of apostomes were present, those corresponding to descriptions of species of Hyalophysa as well as variant forms. The morphotypes observed in this study had the following characteristics: variations in the formation of the anterior ventral field of kinetosomes from falciform field 9; variations in the degree to which ciliary row 1 (kinety 1) was separated into 2 segments; and variations in the development of kinety a. A record of the variant morphotypes that do not correspond exactly to an established species should prove useful to biologists attempting to identify apostomes from crustacean molts. We choose not to name the variant forms as new species because they exist as different morphotypes within a population of cells, because some of these types occur in low frequency, and because one of the variant forms changes from one morphotype to another

Kinorhynch diversity in the southern Gulf of Mexico and a description of Dracoderes chaac sp. nov.

Sediment collections from the southern Gulf of Mexico between the Texas—Mexico border and the Yucatán Peninsula have resulted in many new kinorhynch species distribution records and the finding and taxonomic description of a new species, Dracoderes chaac sp. nov. This study focused on the non—echinoderid members of the Phylum Kinorhyncha, many of which are rare or restricted to only a few locations. A total of 136 specimens were identified from 24 sediment stations, distributed among the following species: Antygomonas gwenae, Campyloderes vanhoeffeni, Centroderes readae, Condyloderes flosfimbriatus, Co. rohalorum, Cristaphyes panamensis, Dracoderes chaac sp. nov., Leiocanthus corrugatus, L. langi, L. quinquenudus, L. satanicus, Pycnophyes alexandroi, Semnoderes lusca, and Sphenoderes aspidochelone. Additional undescribed species in the genera Leiocanthus, Mixtophyes, and Paracentrophyes were recovered. Statistical analysis of the stations revealed a grouping of locations where the majority of the pycnophyid species were recovered. Some species (e.g., Ca. vanhoeffeni, S. aspidochelone) had an extensive distribution, while others were recorded from one or few locations only (e.g., A. gwenae, Co. rohalorum). Most of the species were reported from earlier collections in the northern Gulf of Mexico on the U.S. continental shelf, between 700–1100 km away

Worst Case Resistance Testing: A Nonresponse Bias Solution for Today's Behavioral Research Realities

This study proposes a method of nonresponse assessment based on meta-analytical file-drawer techniques, also known as worst-case resistance testing (WCRT), and suitable for a wide range of data collection scenarios. A general method is devised to estimate the number of significantly different nonrespondents it would take to significantly alter the results of an analysis. Estimates of nonrespondents can be plotted against effect sizes using "n-curves", with similar interpretation to p-curves or power curves. Variants of the general method are derived for tests of means and correlations. A sample using a well-established survey instrument from previous behavioral research is used to test the method. The results suggest that employing worst-case resistance testing can be used on its own or in conjunction with wave analysis to precisely flag nonresponse risks