1,491 research outputs found

    Repair of major system elements on Skylab

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    In-flight maintenance, as conceived and preplanned for the Skylab mission was limited to simple scheduled and unscheduled replacement tasks and minor contingency repairs. Tools and spares were provided accordingly. However, failures during the mission dictated complicated and sophisticated repairs to major systems so that the mission could continue. These repairs included the release of a large structure that failed to deploy, the assembly and deployment of large mechanical devices, the installation and checkout of precision electronic equipment, troubleshooting and repair of precision electromechanical equipment, and tapping into and recharging a cooling system. The repairs were conducted both inside the spacecraft and during extravehicular activities. Some of the repair tasks required team effort on the part of the crewmen including close procedural coordination between internal and extravehicular crewmen. The Skylab experience indicates that crewmen can, with adequate training, make major system repairs in space using standard or special tools. Design of future spacecraft systems should acknowledge this capability and provide for more extensive in-flight repair and maintenance

    Sun direction detection system

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    One of the detectors is an illumination detector consisting of two spaced apart elongated strips with a strip of cadmium sulphide (Cds) deposited therebetween. Whenever the line image impinges the CdS strip, the resistance between the two other strips is relatively low, while being high when the line image is outside the field of view of the illumination detector. Also included is a sun angle detector which consists of a vapor deposited resistor strip connected at one end to plus 10v and at the other end to minus 10v. Spaced apart from the resistor strip is an elongated strip of low resistance material acting as an output strip, with a CdS strip between the two strips. When the line image is within the field of view of the sun angle detector, the output voltage at the output strip depends on the position of the line image across the sun angle detector

    Development, fabrication and testing of a magnetically connected plastic vacuum probe surface sampler

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    The sampler utilizes permanent magnets and soft metal pole pieces to connect the cone/filter assembly to the sampling head and vacuum supply. The cone/filter assembly is packaged in a plastic container and presterilized so that the need for any human contact during the sampling procedure is completely eliminated. Microbiological tests have demonstrated that the sampling efficiency is not affected by the magnetic coupling apparatus and that the probe appears to function as efficiently as the conventional plastic and Sandia vacuum probes

    Lithium abundance evolution in open clusters: Hyades, NGC752, and M67

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    Mixing mechanisms bring the Li from the base of the convective zone to deeper and warmer layers where it is destroyed. These mechanisms are investigated by comparing observations of Li abundances in stellar atmospheres to models of stellar evolution. Observations in open cluster are especially suitable for this comparison, since their age and metallicity are homogeneous among their members and better determined than in field stars. In this work, we compare the evolution of Li abundances in three different clusters: the Hyades, NGC752, and M67. Our models are calculated with microscopic diffusion and transport of chemicals by meridional circulation, and calibrated on the Sun. These comparisons allow us to follow the evolution of Li abundance as a function of stellar mass in each cluster and as a function of the age by comparing this evolution in each cluster. We evaluate the efficiency of the mixing mechanisms used in the models, and we try to identify the lacking mechanisms to reproduce the observed evolution of Li abundance.Comment: 6 pages, 4 figures, conference publication of "New advances in stellar physics: from microscopic to macroscopic processes

    United States v. Thompson Et Al, Civil No. 2565, January 12, 1953

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    This court case dated January 12, 1953, between the United States and Frank Thompson et al, is a civil case involving a declaration of taking for lands needed for the Garrison Dam project. The case was prepared and filed on behalf of the Army Corps of Engineers by Frank Pace Jr., Secretary of the Army. The lands in question are located in Montrail and Williams counties in North Dakota. The case states the justification and precedents for the taking and establishes values for the tracts of land to be seized. Included among the case documents are three property maps that identify the tracts of land in question.https://commons.und.edu/burdick-papers/1027/thumbnail.jp

    ASTEP user's guide and software documentation

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    The Algorithm Simulation Test and Evaluation Program (ASTEP) is a modular computer program developed for the purpose of testing and evaluating methods of processing remotely sensed multispectral scanner earth resources data. ASTEP is written in FORTRAND V on the UNIVAC 1110 under the EXEC 8 operating system and may be operated in either a batch or interactive mode. The program currently contains over one hundred subroutines consisting of data classification and display algorithms, statistical analysis algorithms, utility support routines, and feature selection capability. The current program can accept data in LARSC1, LARSC2, ERTS, and Universal formats, and can output processed image or data tapes in Universal format

    Relationship of Institutional Characteristics to CACREP Accreditation of Doctoral Counselor Education Programs

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    There is a lack of accredited doctoral-level counselor education and supervision (CES) programs available to meet the documented and growing need for more qualified and competent professional counselors. The problem addressed via this study is the shortage of trained doctoral-level counselors and counselor faculty to train other counselors due to the lack of accredited doctoral-level CES programs. The purpose of this study was to better understand the factors that may influence or predict an institution\u27s decision to pursue Council for Accreditation of Counseling and Related Educational Programs (CACREP) accreditation in order to increase the number of programs that pursue specialized accreditation. The research question focused on understanding the predictive relationship between institutional factors and CACREP accreditation status. A quantitative, cross-sectional correlation design was employed that used existing secondary data provided by institutions on institutional, government, and CACREP websites, as well as existing literature. The target population was 91 doctoral-level CES programs offered through U.S. institutions. Key findings from both correlational and logistic regression analyses indicated that the existence of master\u27s-level CACREP accredited programs was the strongest predictor of CACREP-accredited doctoral-level CES programs. Graduate enrollment and the public/private status of an institution were also found to be predictors of doctoral-level CES CACREP accreditation status. Increased availability of accredited doctoral CES programs would impact the number of highly trained counselors practicing within mental health services, thereby improving quality of life for counseling clients, their families, employers, communities, and society

    Monte carlo simulation of midcourse guidance /tapp mod ii/

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    Linear perturbation model used for Monte Carlo simulation of midcourse guidance proble

    Toxicity and morbility after isolated lower limb perfusion in 242 chemo-hyperthermal treatments for cutaneous melanoma: The experience of the Tuscan Reference Centre

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    <p>Abstract</p> <p>Background</p> <p>The aim of this retrospective study was to assess the results concerning the regional and systemic toxicity and complications in 242 chemo-hyperthermal treatments (HILPs) for lower limb melanoma.</p> <p>Patients and methods</p> <p>60 HILPs (G-A) were performed with mild HT plus L-PAM (10 mg/lt) ± D-actimomycin; 74 HILPs (G-B) with true HT (40–41.8°C) plus L-PAM (10 mg/lt) ± D-act; 108 HILPs (G-C) with true HT plus L-PAM (10 mg/lt) ± D-act plus L-PAM (5 mg/lt) additional bolus.</p> <p>Results</p> <p>Limb toxicity was very low in G-A and in G-B; increasing toxicity (grade III = 37%) in G-C; no grade IV statistical difference was registered in all three groups, with percentage values among 1.6% and 2.7%. Systemic toxicity showed itself only in the haemopoietic parameters. No differences were registered in G-B vs G-A group. In G-C vs G-B a significative increase of systemic toxicity was seen in grade 3 (p < 0.05). Postoperative complications were acceptable. Local and systemic side-effects were transient; no permanent neurological limb deficit was registered. The postoperative mortality was recorded in 3/182 HILPs (1.6%) of the G-B and G-C groups.</p> <p>Conclusion</p> <p>These data suggested that the technical implementations reduced the occurrence and the severity of the side effects and complications. The essential requirement for HILP is the quality assurance of the procedures. Although higher regional and systemic toxicity were observed in the G-C group caused by L-PAM additional bolus, the safeness of the procedures under the true hyperthermal regimen and the time increase of the high L-PAM concentration have assured the treatment reliability along with the increased clinical efficacy expectations of the treatments.</p
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