453 research outputs found

    Aglomerasi dan Pengaruh Aliran Dana Sektor Moneter pada Pertumbuhan Sektor Riil di Wilayah Cilacap – Banyumas dan Sekitarnya

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    The determining Cilacap District as an economic core area of southwest Central Java should be assisted in such a way soas to be able to significantly accelerate the growth of the regions and whole of the south area. Based on the region potential mapping, this research found that the real sector activities in Cilacap was more dominance than the other district in south area. So were the financial activities, flow of loan to manufacturing sector in Cilacap also dominance comparred to the other regions. From human development side, Cilacap, as indicated by rising Human Development Index and higher rate of income per capita of most of the inhabitant, had a better condition than other region. The main obstacle to develop industrial area in the region was lack and low quality of infrastructure. Inexpediently condition of road and lack of effort to improve the infrastructure would impede new investment. According to parameter of causality relationshp between real and financial sector of the region, advancement of real sector was supported by productive financially sector. High loan to deposit ratio in the region will encourage regional development and economic growth, especially as long as non-consumptive loan had been improved, it would push the manufacturing industris growth up

    Observations of a pulse driven cool polar jet by SDO/AIA

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    Context. We observe a solar jet at north polar coronal hole (NPCH) using SDO AIA 304 {\deg}A image data on 3 August 2010. The jet rises obliquely above the solar limb and then retraces its propagation path to fall back. Aims. We numerically model this observed solar jet by implementing a realistic (VAL-C) model of solar temperature. Methods. We solve two-dimensional ideal magnetohydrodynamic equations numerically to simulate the observed solar jet. We consider a localized velocity pulse that is essentially parallel to the background magnetic field lines and initially launched at the top of the solar photosphere. The pulse steepens into a shock at higher altitudes, which triggers plasma perturbations that exhibit the observed features of the jet. The typical direction of the pulse also clearly exhibits the leading front of the moving jet. Results. Our numerical simulations reveal that a large amplitude initial velocity pulse launched at the top of the solar photosphere produces in general the observed properties of the jet, e.g., upward and backward average velocities, height, width, life-time, and ballistic nature. Conclusions. The close matching between the jet observations and numerical simulations provides first strong evidence for the formation of this jet by a single velocity pulse. The strong velocity pulse is most likely generated by the low- atmospheric reconnection in the polar region which results in triggering of the jet. The downflowing material of the jet most likely vanishes in the next upcoming velocity pulses from lower solar atmosphere, and therefore distinctly launched a single jet upward in the solar atmosphere is observed.Comment: 8 pages, 4 figures, A&

    Spectroscopic signature of Alfv\'en waves damping in a polar coronal hole up to 0.4 solar radii

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    Between February 24-25, 2009, the EIS spectrometer onboard the Hinode spacecraft performed special "sit & stare" observations above the South polar coronal hole continuously over more than 22 hours. Spectra were acquired with the 1" slit placed off-limb covering altitudes up to 0.48 R_\odot (3.34×1023.34\times 10^2 Mm) above the Sun surface, in order to study with EIS the non-thermal spectral line broadenings. Spectral lines such as Fe {\sc xii} λ\lambda186.88, Fe {\sc xii} λ\lambda193.51, Fe {\sc xii} λ\lambda195.12 and Fe {\sc xiii} λ\lambda202.04 are observed with good statistics up to high altitudes and they have been analyzed in this study. Results show that the FWHM of Fe {\sc xii} λ\lambda195.12 line increases up to 0.14\simeq 0.14 R_\odot, then decreases higher up. EIS stray light has been estimated and removed. Derived electron density and non-thermal velocity profiles have been used to estimate the total energy flux transported by Alfv\'en waves off-limb in polar coronal hole up to 0.4\simeq 0.4 R_\odot. The computed Alfv\'en wave energy flux density fwf_w progressively decays with altitude from fw1.2106f_w \simeq 1.2 \cdot 10^6 erg cm2^{-2} s1^{-1} at 0.03 R_\odot down to fw8.5103f_w \simeq 8.5 \cdot 10^3 erg cm2^{-2} s1^{-1} at 0.4 R_\odot, with an average energy decay rate Δfw/Δh4.5105\Delta f_w / \Delta h \simeq -4.5 \cdot 10^{-5} erg cm3^{-3} s1^{-1}. Hence, this result suggests energy deposition by Alfv\'en waves in a polar coronal hole, thus providing a significant source for coronal heating.Comment: Physical units of the Alfv\'en wave Energy Decay Rate Δfw/Δh\Delta f_w / \Delta h revised with respect to the published version. Scientific results and conclusions unchange

    Explosive events - swirling transition region jets

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    In this paper, we extend our earlier work to provide additional evidence for an alternative scenario to explain the nature of so-called `explosive events'. The bi-directed, fast Doppler motion of explosive events observed spectroscopically in the transition region emission is classically interpreted as a pair of bidirectional jets moving upward and downward from a reconnection site. We discuss the problems of such a model. In our previous work, we focused basically on the discrepancy of fast Doppler motion without detectable motion in the image plane. We now suggest an alternative scenario for the explosive events, based on our observations of spectral line tilts and bifurcated structure in some events. Both features are indicative of rotational motion in narrow structures. We explain the bifurcation as the result of rotation of hollow cylindrical structures and demonstrate that such a sheath model can also be applied to explain the nature of the puzzling `explosive events'. We find that the spectral tilt, the lack of apparent motion, the bifurcation, and a rapidly growing number of direct observations support an alternative scenario of linear, spicular-sized jets with a strong spinning motion.Comment: 9 pages, 3 figures, accepted for publication in Solar Physic

    2D and 3D Polar Plume Analysis from the Three Vantage Positions of STEREO/EUVI A, B, and SOHO/EIT

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    Polar plumes are seen as elongated objects starting at the solar polar regions. Here, we analyze these objects from a sequence of images taken simultaneously by the three spacecraft telescopes STEREO/EUVI A and B, and SOHO/EIT. We establish a method capable of automatically identifying plumes in solar EUV images close to the limb at 1.01 - 1.39 R in order to study their temporal evolution. This plume-identification method is based on a multiscale Hough-wavelet analysis. Then two methods to determined their 3D localization and structure are discussed: First, tomography using the filtered back-projection and including the differential rotation of the Sun and, secondly, conventional stereoscopic triangulation. We show that tomography and stereoscopy are complementary to study polar plumes. We also show that this systematic 2D identification and the proposed methods of 3D reconstruction are well suited, on one hand, to identify plumes individually and on the other hand, to analyze the distribution of plumes and inter-plume regions. Finally, the results are discussed focusing on the plume position with their cross-section area.Comment: 22 pages, 10 figures, Solar Physics articl

    Parasite avoidance behaviours in aquatic environments

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    Parasites, including macroparasites, protists, fungi, bacteria and viruses, can impose a heavy burden upon host animals. However, hosts are not without defences. One aspect of host defence, behavioural avoidance, has been studied in the terrestrial realm for over 50 years, but was first reported from the aquatic environment approximately 20 years ago. Evidence has mounted on the importance of parasite avoidance behaviours and it is increasingly apparent that there are core similarities in the function and benefit of this defence mechanism between terrestrial and aquatic systems. However, there are also stark differences driven by the unique biotic and abiotic characteristics of terrestrial and aquatic (marine and freshwater) environments. Here, we review avoidance behaviours in a comparative framework and highlight the characteristics of each environment that drive differences in the suite of mechanisms and cues that animals use to avoid parasites. We then explore trade-offs, potential negative effects of avoidance behaviour and the influence of human activities on avoidance behaviours. We conclude that avoidance behaviours are understudied in aquatic environments but can have significant implications for disease ecology and epidemiology, especially considering the accelerating emergence and re-emergence of parasites.peerReviewe

    Observations of quasi-periodic phenomena associated with a large blowout solar jet

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    A variety of periodic phenomena have been observed in conjunction with large solar jets. We aim to find further evidence for {(quasi-)}periodic behaviour in solar jets and determine what the periodic behaviour can tell us about the excitation mechanism and formation process of the large solar jet. Using the 304 {\AA} (He-II), 171 {\AA} (Fe IX), 193 {\AA} (Fe XII/XXIV) and 131 {\AA} (Fe VIII/XXI) filters on-board the Solar Dynamic Observatory (SDO) Atmospheric Imaging Assembly (AIA), we investigate the intensity oscillations associated with a solar jet. Evidence is provided for multiple magnetic reconnection events occurring between a pre-twisted, closed field and open field lines. Components of the jet are seen in multiple SDO/AIA filters covering a wide range of temperatures, suggesting the jet can be classified as a blowout jet. Two bright, elongated features are observed to be co-spatial with the large jet, appearing at the jet's footpoints. Investigation of these features reveal they are defined by multiple plasma ejections. The ejecta display (quasi-)periodic behaviour on timescales of 50 s and have rise velocities of 40-150 km\,s1^{-1} along the open field lines. Due to the suggestion that the large jet is reconnection-driven and the observed properties of the ejecta, we further propose that these ejecta events are similar to type-II spicules. The bright features also display (quasi)-periodic intensity perturbations on the timescale of 300 s. Possible explanations for the existence of the (quasi-)periodic perturbations in terms of jet dynamics and the response of the transition region are discussed.Comment: Astronomy and Astrophysics - In Prin
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