335 research outputs found

    A CASE STUDY OF LUNTIAN MULTI-PURPOSE COOPERATIVE IN BARANGAY LALAIG, TIAONG, QUEZON, PHILIPPINES: A VERTICAL INTEGRATION APPROACH

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    The Luntian Multi-Purpose Cooperative located in Tiaong, Quezon, Philippines. The Luntian Multi-Purpose cooperative focuses more on feed production as well as hog fattening. The LMC applied the vertical integration to develop the cooperative. They have their members as their primary costumers of their feeds. The cooperative’s business activity includes also meat shop, granting of production loan, micro-finance, mobilization of saving deposits, aside from feed milling and hog fattening. Different agencies, industry organizations and private institutions provide trainings, seminars, assistance, as well as credit for the cooperative.The aims of the study was to determine the present and discuss a noteworthy business issue (s) of Luntian Multipurpose Cooperative, evaluate the business environment prevailing at a particular time of this case , assess the cooperative’s performance in terms of the four business functions , define the problem relevant to the business issue(s) being studied. The study used primary and secondary data. Primary data were gathered through interviews with the key personnel, managers, and other informants of the Luntian Multipurpose Cooperative in order to obtain responses regarding the overall status of the cooperative including its problem and plans. Secondary data were taken from files and documents, especially the history, background information and financial statements. Other data were taken through research materials such as book, unpublished special problems and from some government institutions. The recommendation of this research showed that Luntian MPC should engage in establishing a communal farm as to become the primary source of hybrid piglets that their members would raised. The alternatives solution was establishing a breeding farm that would ask for initial investment. Keywords: cooperative, vertical integration, case study, por

    Estudio ornitológico de los parques y alrededores de Pamplona

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    Se ha estudiado la ornitofauna de 5 parques de Pamplona y 4 áreas de su periferia. Respecto al estudio cualitativo, se ha realizado una clasificación fenológica de las aves observadas, habiéndose catalogado 110 especies. En relación al estudio cuantitativo, se ha procedido a la comparación de las distintas áreas muestreadas mediante métodos estadísticos, habiéndose encontrado gran similitud entre los parques de mayor extensión incluidos en el casco de la ciudad. De igual modo se encuentra una más estrecha relación entre las áreas ribereñas del río Arga, que la existente entre otras zonas de la periferia

    Origin of supermassive black holes: predictions for the black hole population

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    The presence of supermassive black holes at redshift z > 6 raises some questions about their formation and growth in the early universe. Due to the construction of new telescopes like the ELT to observe and detect SMBHs, it will be useful to derive theoretical estimates for the population and to compare observations and model predictions in the future. In consequence our main goal is to estimate the population of SMBHs using a semi-analytic code known as Galacticus which is a code for the formation and evolution of galaxies where we are about to include different scenarios for SMBHs formation indicating the initial mass of the black hole seed, its formation conditions and recipes for the evolution of the components of the galaxies. We found that the principal mechanism of growing SMBHs is is via galaxy mergers and accretion of matter. For the comparison of our results with observations, we calculate the radius of influence of the black hole to estimate which part of the population could be detected, leading to relations similar to the observed ones.Comment: 3 pages, 3 figure

    Global instability by runaway collisions in nuclear stellar clusters: Numerical tests of a route for massive black hole formation

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    The centers of galaxies host nuclear stellar clusters, supermassive black holes, or both, but the origin of this dichotomy is still a mystery. Nuclear stellar clusters are the densest stellar system of the Universe, so they are ideal places for runaway collisions to occur. In these dense clusters it is possible that global instability occurs, triggered by collisions and mergers forming a massive black hole. Here we test a new mechanism to form massive black holes through runaway stellar collisions in nuclear stellar clusters, performing N-body simulations using the code nbody6++gpu. Our idealized models show that there is a critical mass where collisions become very efficient making it possible to form massive black holes in nuclear stellar clusters. The most massive objects reach masses of the order of 104−105 M⊙10^4-10^5\rm~ M_\odot. We find that our highest black hole formation efficiency is up to 50%50\% of the stellar mass at the end of the simulation. In real astrophysical systems, the critical mass scale for this transition is expected to occur in stellar clusters of 107−109 M⊙10^7-10^9\rm~M_\odot, implying the formation of quite massive central objects.Comment: 11 pages, 6 figure

    Limiting eccentricity of sub-parsec massive black hole binaries surrounded by self-gravitating gas discs

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    We study the dynamics of supermassive black hole binaries embedded in circumbinary gaseous discs, with the SPH code Gadget-2. The sub-parsec binary (of total mass M and mass ratio q=1/3) has excavated a gap and transfers its angular momentum to the self--gravitating disc (M_disc=0.2 M). We explore the changes of the binary eccentricity e, by simulating a sequence of binary models that differ in the initial eccentricity e_0, only. In initially low-eccentric binaries, the eccentricity increases with time, while in high-eccentric binaries e declines, indicating the existence of a limiting eccentricity e_crit that is found to fall in the interval [0.6,0.8]. We also present an analytical interpretation for this saturation limit. An important consequence of the existence of e_crit is the detectability of a significant residual eccentricity e_LISA} by the proposed gravitational wave detector LISA. It is found that at the moment of entering the LISA frequency domain e_LISA ~ 10^{-3}-10^{-2}; a signature of its earlier coupling with the massive circumbinary disc. We also observe large periodic inflows across the gap, occurring on the binary and disc dynamical time scales rather than on the viscous time. These periodic changes in the accretion rate (with amplitudes up to ~100%, depending on the binary eccentricity) can be considered a fingerprint of eccentric sub-parsec binaries migrating inside a circumbinary disc.Comment: 10 pages, 7 figures, accepted for publication in MNRA

    Direct Formation of Supermassive Black Holes via Multi-Scale Gas Inflows in Galaxy Mergers

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    Observations of distant bright quasars suggest that billion solar mass supermassive black holes (SMBHs) were already in place less than a billion years after the Big Bang. Models in which light black hole seeds form by the collapse of primordial metal-free stars cannot explain their rapid appearance due to inefficient gas accretion. Alternatively, these black holes may form by direct collapse of gas at the center of protogalaxies. However, this requires metal-free gas that does not cool efficiently and thus is not turned into stars, in contrast with the rapid metal enrichment of protogalaxies. Here we use a numerical simulation to show that mergers between massive protogalaxies naturally produce the required central gas accumulation with no need to suppress star formation. Merger-driven gas inflows produce an unstable, massive nuclear gas disk. Within the disk a second gas inflow accumulates more than 100 million solar masses of gas in a sub-parsec scale cloud in one hundred thousand years. The cloud undergoes gravitational collapse, which eventually leads to the formation of a massive black hole. The black hole can grow to a billion solar masses in less than a billion years by accreting gas from the surrounding disk.Comment: 26 pages, 4 Figures, submitted to Nature (includes Supplementary Information
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