974 resultados para Drone aircraft


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Sex-related differences in susceptibility to pathogens are a common phenomenon in animals. In the eusocial Hymenoptera the two female castes, workers and queens, are diploid and males are haploid. The haploid susceptibility hypothesis predicts that haploid males are more susceptible to pathogen infections compared to females. Here we test this hypothesis using adult male (drone) and female (worker) honey bees (Apis mellifera), inoculated with the gut endoparasite Nosema ceranae and/or black queen cell virus (BQCV). These pathogens were chosen due to previously reported synergistic interactions between Nosema apis and BQCV. Our data do not support synergistic interactions between N. ceranae and BQCV and also suggest that BQCV has limited effect on both drone and worker health, regardless of the infection level. However, the data clearly show that, despite lower levels of N. ceranae spores in drones than in workers, Nosema-infected drones had both a higher mortality and a lower body mass than non-infected drones, across all treatment groups, while the mortality and body mass of worker bees were largely unaffected by N. ceranae infection, suggesting that drones are more susceptible to this pathogen than workers. In conclusion, the data reveal considerable sex-specific differences in pathogen susceptibility in honey bees and highlight the importance of ultimate measures for determining susceptibility, such as mortality and body quality, rather than mere infection levels

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We introduce a new boundary layer formalism on the basis of which a class of exact solutions to the Navier–Stokes equations is derived. These solutions describe laminar boundary layer flows past a flat plate under the assumption of one homogeneous direction, such as the classical swept Hiemenz boundary layer (SHBL), the asymptotic suction boundary layer (ASBL) and the oblique impingement boundary layer. The linear stability of these new solutions is investigated, uncovering new results for the SHBL and the ASBL. Previously, each of these flows had been described with its own formalism and coordinate system, such that the solutions could not be transformed into each other. Using a new compound formalism, we are able to show that the ASBL is the physical limit of the SHBL with wall suction when the chordwise velocity component vanishes while the homogeneous sweep velocity is maintained. A corresponding non-dimensionalization is proposed, which allows conversion of the new Reynolds number definition to the classical ones. Linear stability analysis for the new class of solutions reveals a compound neutral surface which contains the classical neutral curves of the SHBL and the ASBL. It is shown that the linearly most unstable Görtler–Hämmerlin modes of the SHBL smoothly transform into Tollmien–Schlichting modes as the chordwise velocity vanishes. These results are useful for transition prediction of the attachment-line instability, especially concerning the use of suction to stabilize boundary layers of swept-wing aircraft.

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Currently, most cosmic ray data are obtained by detectors on satellites, aircraft, high-altitude balloons and ground (neutron monitors). In our work, we examined whether Liulin semiconductor spectrometers (simple silicon planar diode detectors with spectrometric properties) located at high mountain observatories could contribute new information to the monitoring of cosmic rays by analyzing data from selected solar events between 2005 and 2013. The decision thresholds and detection limits of these detectors placed at Jungfraujoch (Switzerland; 3475 m a.s.l.; vertical cut-off rigidity 4.5 GV) and Lomnicky stıt (Slovakia; 2633 m a.s.l.; vertical cut-off rigidity 3.84 GV) highmountain observatories were determined. The data showed that only the strongest variations of the cosmic ray flux in this period were detectable. The main limitation in the performance of these detectors is their small sensitive volume and low sensitivity of the PIN photodiode to neutrons.

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A three-level satellite to ground monitoring scheme for conservation easement monitoring has been implemented in which high-resolution imagery serves as an intermediate step for inspecting high priority sites. A digital vertical aerial camera system was developed to fulfill the need for an economical source of imagery for this intermediate step. A method for attaching the camera system to small aircraft was designed, and the camera system was calibrated and tested. To ensure that the images obtained were of suitable quality for use in Level 2 inspections, rectified imagery was required to provide positional accuracy of 5 meters or less to be comparable to current commercially available high-resolution satellite imagery. Focal length calibration was performed to discover the infinity focal length at two lens settings (24mm and 35mm) with a precision of O.1mm. Known focal length is required for creation of navigation points representing locations to be photographed (waypoints). Photographing an object of known size at distances on a test range allowed estimates of focal lengths of 25.lmm and 35.4mm for the 24mm and 35mm lens settings, respectively. Constants required for distortion removal procedures were obtained using analytical plumb-line calibration procedures for both lens settings, with mild distortion at the 24mm setting and virtually no distortion found at the 35mm setting. The system was designed to operate in a series of stages: mission planning, mission execution, and post-mission processing. During mission planning, waypoints were created using custom tools in geographic information system (GIs) software. During mission execution, the camera is connected to a laptop computer with a global positioning system (GPS) receiver attached. Customized mobile GIs software accepts position information from the GPS receiver, provides information for navigation, and automatically triggers the camera upon reaching the desired location. Post-mission processing (rectification) of imagery for removal of lens distortion effects, correction of imagery for horizontal displacement due to terrain variations (relief displacement), and relating the images to ground coordinates were performed with no more than a second-order polynomial warping function. Accuracy testing was performed to verify the positional accuracy capabilities of the system in an ideal-case scenario as well as a real-world case. Using many welldistributed and highly accurate control points on flat terrain, the rectified images yielded median positional accuracy of 0.3 meters. Imagery captured over commercial forestland with varying terrain in eastern Maine, rectified to digital orthophoto quadrangles, yielded median positional accuracies of 2.3 meters with accuracies of 3.1 meters or better in 75 percent of measurements made. These accuracies were well within performance requirements. The images from the digital camera system are of high quality, displaying significant detail at common flying heights. At common flying heights the ground resolution of the camera system ranges between 0.07 meters and 0.67 meters per pixel, satisfying the requirement that imagery be of comparable resolution to current highresolution satellite imagery. Due to the high resolution of the imagery, the positional accuracy attainable, and the convenience with which it is operated, the digital aerial camera system developed is a potentially cost-effective solution for use in the intermediate step of a satellite to ground conservation easement monitoring scheme.

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1 Brief von Max Horkheimer an Abel, 16.03.1936; 3 Briefe zwischen Hubert Abrahamsohn und Max Horkheimer, 1935-1936, 21.12.1936; 2 Briefe zwischen Emanuel Adler und Max Horkheimer, 12.04.1946, 26.04.1946; 2 Briefe zwischen Max Adler und Max Horkheimer, 16.03.1935, 29.03.1935; 1 Brief von Eva Ahamson an Max Horkheimer, 01.11.1944; 2 Briefe der Aircraft Warning Service Brentwood an Max Horkheimer, Mai 1942; 6 Briefe zwischen Librairie Félix Alcan und Max Horkheimer, 1935, 18.12.1935; 11 Briefe zwischen Franz Alexander und Max Horkheimer, 1938-1940; 2 Briefe zwischen der American Historical Review New York und Max Horkheimer, 01.04.1941, 07.04.1941; 1 Brief von Paul Reiwald an Max Horkheimer, 18.10.1940; 2 Briefe zwischen Helen Manice Alexander und Max Horkheimer, 1936; 2 Briefe zwischen Bernardine Allen und Max Horkheimer, 17.06.1938, 24.06.1938; 1 Brief der Alumni Federation of Columbia University an Max Horkheimer, 21.07.1942; 1 Brief der American Friends Service Comittee an Max Horkheimer, 10.12.1940; 3 Briefe zwischen der American Academy of Political and Social Science Philadelphia und Max Horkheimer, 1939,1940, 16.01.1939; 1 Brief der American Automobile Association Washington an Max Horkheimer, 22.03.1938; 1 Brief der American Association for the Advancement of Science Washington an Max Horkheimer, 16.08.1937; 2 Briefe von Max Horkheimer an den American Consulate General Berlin, 1939; 1 Brief von Max Horkheimer an den American Consulate General Havana, 03.03.1941; 4 Briefe von Max Horkheimer an den American Consul London, 1939-1941; 2 Briefe von Max Horkheimer an den American Consulate General Stuttgart, 1939-1941; 1 Brief von Max Horkheimer an den American Consul Zürich, 1939; 1 Brief von Friedrich Pollock an den American Council of Learned Society, Washington, 27.06.1941; 2 Briefe von Max Horkheimer an die American Friends of German Freedom New York, 1941; 4 Briefe der American Historical Association Washington an Max Horkheimer, 1937-1938; 1 Brief von Max Horkheimer an den American Red Cross Westwood Office, 21.06.1943; 18 Briefe zwschen der American Society for the Prevention of Cruelty to Animals New York und Max Horkheimer, 1936-1941; 1 Brief von Max Horkheimer an die American Women's Volunteer Service Pacific Palisades, 27.07.1942; 23 Briefe zwischen Eugene Anderson und Max Horkheimer, 1937-1941; 2 Briefe zwischen Norah Andreae und Max Horkheimer, 27.10.1944, 09.09.1946; 1 Brief von Rosa Nebel-Schenk, 04.03.1946; 1 Brief von der National Catholic Welfare Conference, 14.08.1944; 12 Briefe zwischen Werner Andreae und Max Horkheimer, 1945-1954; 1 Brief von Julius Marx an Werner Andreae, 10.05.1946, 11.05.1950; 2 Briefe von Josef Messinger an Werner Andreae, 23.10.1946, ohne Datum; 3 Briefe zwischen dem Advokatenbüro Hodler und Max Horkheimer, 1946, 09.05.1946;

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Background: The failure rate of health information systems is high, partially due to fragmented, incomplete, or incorrect identification and description of specific and critical domain requirements. In order to systematically transform the requirements of work into real information system, an explicit conceptual framework is essential to summarize the work requirements and guide system design. Recently, Butler, Zhang, and colleagues proposed a conceptual framework called Work Domain Ontology (WDO) to formally represent users’ work. This WDO approach has been successfully demonstrated in a real world design project on aircraft scheduling. However, as a top level conceptual framework, this WDO has not defined an explicit and well specified schema (WDOS) , and it does not have a generalizable and operationalized procedure that can be easily applied to develop WDO. Moreover, WDO has not been developed for any concrete healthcare domain. These limitations hinder the utility of WDO in real world information system in general and in health information system in particular. Objective: The objective of this research is to formalize the WDOS, operationalize a procedure to develop WDO, and evaluate WDO approach using Self-Nutrition Management (SNM) work domain. Method: Concept analysis was implemented to formalize WDOS. Focus group interview was conducted to capture concepts in SNM work domain. Ontology engineering methods were adopted to model SNM WDO. Part of the concepts under the primary goal “staying healthy” for SNM were selected and transformed into a semi-structured survey to evaluate the acceptance, explicitness, completeness, consistency, experience dependency of SNM WDO. Result: Four concepts, “goal, operation, object and constraint”, were identified and formally modeled in WDOS with definitions and attributes. 72 SNM WDO concepts under primary goal were selected and transformed into semi-structured survey questions. The evaluation indicated that the major concepts of SNM WDO were accepted by 41 overweight subjects. SNM WDO is generally independent of user domain experience but partially dependent on SNM application experience. 23 of 41 paired concepts had significant correlations. Two concepts were identified as ambiguous concepts. 8 extra concepts were recommended towards the completeness of SNM WDO. Conclusion: The preliminary WDOS is ready with an operationalized procedure. SNM WDO has been developed to guide future SNM application design. This research is an essential step towards Work-Centered Design (WCD).