Cost analysis of carbon dioxide concentrators

A methodology is developed to predict the relevant contributions of the more intangible cost elements encountered in the development of flight-qualified hardware and is used to predict the costs of three carbon dioxide concentration systems. The cost and performance data from Gemini, Skylab, and other programs are utilized as a basis for establishing the cost estimating relationships. The concentration systems analyzed are the molecular sieves C02 concentrator, the hydrogen-depolarized concentrator, and the regenerable solid desiccant concentrator. Besides the cost estimates for each system, their comparative criteria including relative characteristics, operational differences, and development status are considered

Cost analysis of life sciences experiments and subsystems

Cost estimates for experiments and subsystems flown in the Spacelab were established. Ten experiments were cost analyzed. Estimated cost varied from $650,000 for the hardware development of the SPE water electrolysis experiment to$78,500,000 for the development and operation of a representative life sciences laboratory program. The cost of subsystems for thermal, atmospheric and trace contaminants control of the Spacelab internal atmosphere was also estimated. Subsystem cost estimates were based on the utilization of existing components developed in previous space programs whenever necessary

Modelling the components of binaries in Hyades: The dependence of the mixing-length parameter on stellar mass

We present our findings based on a detailed analysis for the binaries of the Hyades, in which the masses of the components are well known. We fit the models of components of a binary system to the observations so as to give the observed total V and B-V of that system and the observed slope of the main-sequence in the corresponding parts. According to our findings, there is a very definite relationship between the mixing-length parameter and the stellar mass. The fitting formula for this relationship can be given as $alpha = 9.19 (M/M_sun-0.74)^{0.053}-6.65$, which is valid for stellar masses greater than 0.77 M_sun. While no strict information is gathered for the chemical composition of the cluster, as a result of degeneracy in the colour-magnitude diagram, by adopting Z=0.033 and using models for the components of 70 Tau and theta^2 Tau we find the hydrogen abundance to be X=0.676 and the age to be 670 Myr. If we assume that Z=0.024, then X=0.718 and the age is 720 Myr. Our findings concerning the mixing length parameter are valid for both sets of the solution. For both components of the active binary system V818 Tau, the differences between radii of the models with Z=0.024 and the observed radii are only about 4 percent. More generally, the effective temperatures of the models of low mass stars in the binary systems studied are in good agreement with those determined by spectroscopic methods.Comment: 11 pages, 7 figures, accepted for publication in MNRA

Parametric study of manned life support systems. Volume 2 - Parametric relations and scaling law Final report, Jul. 1967- Aug. 1968

Parametric relations and scaling laws to describe manned life support system

FIRST DISCOVERY OF MIDDLE TOURNAISIAN CONODONTS IN THE GRIOTTE-TYPE NODULAR PELAGIC LIMESTONES, ISTANBUL AREA, NW TURKEY

The uppermost layers of the Ayineburnu member of the Büyükada Formation in the Istanbul-Gebze area are represented by Griotte-type pelagic nodular limestones. They yielded conodont elements (Bispathodus stabilis and Siphonodella lobata) that can identify the interval from the upper part of the sandbergi Zone through the isosticha- Upper crenulata Zone - middle Tournaisian - Early Carboniferous. This is the first middle Tournaisian conodont record published from an autochthonous succession in the Istanbul Terrane, NW Turkey. This level characterizes the very last carbonate deposition and is followed by lydites and black siliceous shales and finally by the accumulation of flysch-type deposits during the late Tournaisian and early Visean, that mark the onset of Variscan events to the north of the Istanbul Terrane. A correlation with the Lower Carboniferous successions in the easterly-located Zonguldak area suggests that Istanbul and Zonguldak terranes were in quite different palaeogeographic positions during this time interval

Analysis of MERCATOR data Part I: variable B stars

We re-classified 31 variable B stars which were observed more than 50 times in the Geneva photometric system with the P7 photometer attached to the MERCATOR telescope (La Palma) during its first 3 years of scientific observations. HD89688 is a possible beta Cephei/slowly pulsating B star hybrid and the main mode of the COROT target HD180642 shows non-linear effects. The Maia candidates are re-classified as either ellipsoidal variables or spotted stars. Although the mode identification is still ongoing, all the well-identified modes so far have a degree l = 0, 1 or 2.Comment: 4 pages, 3 figures. To appear in: Proceedings of JENAM 2005 'Distant worlds', Communications in Asteroseismolog

Readability and test-retest reliability of a psychometric instrument designed to assess HIV/AIDS attitudes, beliefs, behaviours and sources of HIV prevention information of young adults

Objective: This comparative study evaluated the readability and test-retest reliability of a questionnaire designed to assess the attitudes, beliefs behaviours and sources of information about HIV/AIDS among young adults recruited from universities in the United States of America (USA), Turkey and South Africa. Design/Setting: The instrument was administered on two occasions, within a two week interval, to 219 university students in the USA (n = 66), Turkey (n = 53) and South Africa (n = 100). Method: The psychometric instrument developed has five major subscales: demographic, HIV/AIDS attitudes and beliefs, HIV risk sexual behaviour, alcohol and drug use, and HIV sources of information. Results: The instrument’s readability evaluation revealed a Flesch-Kincaid score (literacy difficulty level of the questionnaire) of 8.4, indicating that respondents would need an eighth grade reading level to understand the survey. The overall test-retest reliability coefficients for the items on the demographic subscale were generally high (0.893–0.997). Similarly, high test-retest reliability was obtained for the HIV risk sexual behaviour (0.738–0.996) and the alcohol and drug use (0.562–1.000) subscales. Much lower test-retest reliability was obtained for the HIV/AIDS attitudes and beliefs (0.32–0.80), and sources of information about HIV/AIDS (0.370–0.892) subscales. Conclusion: We found no discernible difference in the reliability data among the respondents from the three countries. The instrument should be of interest to clinicians and researchers investigating the HIV risk behaviours of young adults and older age groups with an eighth grade reading level. The availability of this instrument may enhance HIV population and intervention studies internationally.Web of Scienc

Close binary stars in the solar-age Galactic open cluster M67

We present multi-colour time-series CCD photometry of the solar-age galactic open cluster M67 (NGC 2682). About 3600 frames spread over 28 nights were obtained with the 1.5 m Russian-Turkish and 1.2 m Mercator telescopes. High-precision observations of the close binary stars AH Cnc, EV Cnc, ES Cnc, the $\delta$ Scuti type systems EX Cnc and EW Cnc, and some long-period variables belonging to M67 are presented. Three full multi-colour light curves of the overcontact binary AH Cnc were obtained during three observing seasons. Likewise we gathered three light curves of EV Cnc, an EB-type binary, and two light curves of ES Cnc, a blue straggler binary. Parts of the light change of long-term variables S1024, S1040, S1045, S1063, S1242, and S1264 are obtained. Period variation analysis of AH Cnc, EV Cnc, and ES Cnc were done using all times of mid-eclipse available in the literature and those obtained in this study. In addition, we analyzed multi-colour light curves of the close binaries and also determined new frequencies for the $\delta$ Scuti systems. The physical parameters of the close binary stars were determined with simultaneous solutions of multi-colour light and radial velocity curves. Finally we determined the distance of M67 as 857(33) pc via binary star parameters, which is consistent with an independent method from earlier studies.Comment: 12 pages, 9 Figures, 13 Table

Study of damage control systems for space station

Damage control systems for detecting and locating overboard and onboard leak and damage modes on space station