1,221 research outputs found

    Finite element analysis of notch behavior using a state variable constitutive equation

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    The state variable constitutive equation of Bodner and Partom was used to calculate the load-strain response of Inconel 718 at 649 C in the root of a notch. The constitutive equation was used with the Bodner-Partom evolution equation and with a second evolution equation that was derived from a potential function of the stress and state variable. Data used in determining constants for the constitutive models was from one-dimensional smooth bar tests. The response was calculated for a plane stress condition at the root of the notch with a finite element code using constant strain triangular elements. Results from both evolution equations compared favorably with the observed experimental response. The accuracy and efficiency of the finite element calculations also compared favorably to existing methods

    HI Observations of the Asymptotic Giant Branch Star X Herculis: Discovery of an Extended Circumstellar Wake Superposed on a Compact High-Velocity Cloud

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    We report HI 21-cm line observations of the AGB star X Her obtained with the Green Bank Telescope (GBT) and the Very Large Array (VLA). We have detected HI emission totaling M_HI=2.1e-03 M_sun associated with the circumstellar envelope of the star. The HI distribution exhibits a head-tail morphology, similar to those previously observed around Mira and RS Cnc. The tail extends ~6.0' (0.24 pc) in the plane of the sky, along the direction of the star's space motion. We also detect a velocity gradient of ~6.5 km/s across the envelope, consistent with the HI tracing a turbulent wake that arises from the motion of a mass-losing star through the ISM. GBT mapping of a 2x2deg region around X Her reveals that the star lies (in projection) near the periphery of a much larger HI cloud that also exhibits signatures of ISM interaction. The properties of the cloud are consistent with those of compact high-velocity clouds. Using CO observations, we have placed an upper limit on its molecular gas content of N_H2<1.3e20 cm^-2. Although the distance to the cloud is poorly constrained, the probability of a chance coincidence in position, velocity, and apparent position angle of space motion between X Her and the cloud is extremely small, suggesting a possible physical association. However, the large HI mass of the cloud (~>2.4~M_sun) and the blueshift of its mean velocity relative to X Her are inconsistent with an origin tied directly to stellar ejection. (abridged)Comment: Accepted to AJ; 47 pages, 15 figures; version with full resolution figures available at http://www.haystack.mit.edu/hay/staff/lmatthew/matthews_XHer.pd

    High-Mass Star Formation in the Outer Scutum-Centaurus Arm

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    The Outer Scutum-Centaurus (OSC) spiral arm is the most distant molecular spiral arm in the Milky Way, but until recently little was known about this structure. Discovered by Dame and Thaddeus (2011), the OSC lies ∼\sim15 kpc from the Galactic Center. Due to the Galactic warp, it rises to nearly 4∘^{\circ} above the Galactic Plane in the first Galactic quadrant, leaving it unsampled by most Galactic plane surveys. Here we observe HII region candidates spatially coincident with the OSC using the Very Large Array to image radio continuum emission from 65 targets and the Green Bank Telescope to search for ammonia and water maser emission from 75 targets. This sample, drawn from the WISE Catalog of Galactic HII Regions, represents every HII region candidate near the longitude-latitude (l,v) locus of the OSC. Coupled with their characteristic mid-infrared morphologies, detection of radio continuum emission strongly suggests that a target is a bona fide HII region. Detections of associated ammonia or water maser emission allow us to derive a kinematic distance and determine if the velocity of the region is consistent with that of the OSC. Nearly 60% of the observed sources were detected in radio continuum, and over 20% have ammonia or water maser detections. The velocities of these sources mainly place them beyond the Solar orbit. These very distant high-mass stars have stellar spectral types as early as O4. We associate high-mass star formation at 2 new locations with the OSC, increasing the total number of detected HII regions in the OSC to 12.Comment: 14 pages text and tables + 10 pages supplemental figure

    Pengaruh Profitabilitas, Struktur Kepemilikan, Pertumbuhan Perusahaan dan Efektivitas USAha terhadap Kebijakan Dividen pada Perusahaan Manufaktur

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    The purpose of this study was to determine the effect Profitability, Ownership Structure, Corporate Growth and Business Effectiveness against Dividend Policy. Dividend policy is important for investors, because investors tend mengingankan profit to be distributed as dividends, while the company wants on hold in order to finance investment in the future akandating, it is necessary to determine the factors that influence the dividend policy. This study was performed on companies listed in Indonesia Stock Exchange 2010-2013. The number of samples taken is 8 companies. The sampling method in this study using purposive sampling and using regression analysis techniques berganda. This study indicate that profitability, ownership structure, and the effectiveness of efforts partially positive effect on the dividend policy, while the business growth negative effect on dividend polic

    Comparative Analysis of Molecular Clouds in M31, M33 and the Milky Way

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    We present BIMA observations of a 2\arcmin field in the northeastern spiral arm of M31. In this region we find six giant molecular clouds that have a mean diameter of 57±\pm13 pc, a mean velocity width of 6.5±\pm1.2 \kms, and a mean molecular mass of 3.0 ±\pm 1.6 ×\times 105^5\Msun. The peak brightness temperature of these clouds ranges from 1.6--4.2 K. We compare these clouds to clouds in M33 observed by \citet{wilson90} using the OVRO millimeter array, and some cloud complexes in the Milky Way observed by \cite{dame01} using the CfA 1.2m telescope. In order to properly compare the single dish data to the spatially filtered interferometric data, we project several well-known Milky Way complexes to the distance of Andromeda and simulate their observation with the BIMA interferometer. We compare the simulated Milky Way clouds with the M31 and M33 data using the same cloud identification and analysis technique and find no significant differences in the cloud properties in all three galaxies. Thus we conclude that previous claims of differences in the molecular cloud properties between these galaxies may have been due to differences in the choice of cloud identification techniques. With the upcoming CARMA array, individual molecular clouds may be studied in a variety of nearby galaxies. With ALMA, comprehensive GMC studies will be feasible at least as far as the Virgo cluster. With these data, comparative studies of molecular clouds across galactic disks of all types and between different galaxy disks will be possible. Our results emphasize that interferometric observations combined with the use of a consistent cloud identification and analysis technique will be essential for such forthcoming studies that will compare GMCs in the Local Group galaxies to galaxies in the Virgo cluster.Comment: Accepted for Publication in the Astrophysical Journa

    Analisa Faktor Ketertarikan Mahasiswa Terhadap Produk Sabun Mandi

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    Analisis konjoin merupakan salah satu teknik analisis multivariat yang digunakan untuk mengetahui preperensi/ ketertarikan konsumen terhadap suatu produk baik berupa barang atau jasa dengan cara mengkombinasikan jumlah nilai dari masing-masing atribut yang terpisah. Preferensi diperoleh dengan mengurutkan kombinasi-kombinasi yang tersedia berdasarkan tingkat kesukaan relatif. Oleh karena itu, penggunaan analisis konjoin sangat membantu penelitian dalam pemasaran terutama untuk penting tidaknya suatu atribut beserta taraf dalam suatu produk atau jasa. Hasil pengolahan analisis konjoin pada penelitian ini mendapatkan informasi bahwa faktor utama Mahasiswa FMIPA USU Strata-1 mengharapkan sabun mandi dengan warna hijau, manfaat untuk melindungi kulit dari kuman, aroma Wewangian kesehatan, harga relatif lebih murah, bentuk cair dan jenis non antiseptic
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