4,281 research outputs found

    Blended-Learning: the Responses From Non-English Students in the Indonesian Tertiary Context

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    The process of language teaching and learning has undergone major changes due to the developments of technology. The use of technology in education field has paved the way for higher education institution to innovatively shape their modern media in a language teaching and learning. Subsequently, the implementation of blended-learning has aroused at the Universitas Teknokrat Indonesia for approximately one and a half year ago to maximize the use of technology. Most lecturers in all study programs have increasingly utilized the social network sites such as Instagram, Facebook, WhatsApp, etc. for the successfulness of blended-learning. This present study aims at exploring the students' responses on how blended-learning might be used to develop their language learning and discovering their attitudes towards the implementation of blended-learning as an interactional teaching and learning tool in English for Business course. Employing a qualitative in form of a case study, eighty-two undergraduate students from study program of Informatics Engineering were observed, interviewed, and distributed questionnaires. The data were performed to collect the students' responses and students' attitudes toward the implementation of blended-learning in the process of their language learning. The findings were found out that most students from Informatics Engineering major showed their positive responses and positive attitudes using blended learning for the language teaching and learning. They also gained some educational benefits for their English language development. Thus, this blended learning brings us to the new trend for language teaching and learning media in order to motivate the students in enhancing their language acquisition

    Power Density Spectra of Gamma-Ray Bursts in the Internal Shock Model

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    We simulate Gamma-Ray Bursts arising from internal shocks in relativistic winds, calculate their power density spectrum (PDS), and identify the factors to which the PDS is most sensitive: the wind ejection features, which determine the wind dynamics and its optical thickness, and the energy release parameters, which give the pulse 50-300 keV radiative efficiency. For certain combinations of ejection features and wind parameters the resulting PDS exhibits the features observed in real bursts. We found that the upper limit on the efficiency of conversion of wind kinetic energy into 50-300 keV photons is ∼\sim 1%. Winds with a modulated Lorentz factor distribution of the ejecta yield PDSs in accord with current observations and have efficiencies closer to 10−310^{-3}, while winds with a random, uniform Lorentz factor ejection must be optically thick to the short duration pulses to produce correct PDSs, and have an overall efficiency around 10−410^{-4}.Comment: 6 pages, 4 figures, Latex, submitted to The Astrophysical Journal (05/04/99

    GRB990123, The Optical Flash and The Fireball Model

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    We compare the ongoing observations of the remarkable burst GRB990123, the mother of all bursts, with the predictions of the afterglow theory. We show that the observations agree with the recent prediction that a reverse shock propagating into the ejecta would produce a very strong prompt optical flash. This reverse shock has also produced the 8.46GHz radio signal, observed after one day. The forward shock, which propagates into the ISM is the origin of the classical afterglow. It has produced the prompt X-ray signal as well as the late optical and IR emission. It would most likely produce a radio emission within the next few weeks. The observations suggest that the initial Lorentz factor of the ejecta was ∼200\sim 200. Within factors of order unity, this crude model explains all current observations of GRB990123.Comment: 14 pages including 2 figure

    The prompt energy release of gamma-ray bursts using a cosmological k-correction

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    The fluences of gamma-ray bursts (GRBs) are measured with a variety of instruments in different detector energy ranges. A detailed comparison of the implied energy releases of the GRB sample requires, then, an accurate accounting of this diversity in fluence measurements which properly corrects for the redshifting of GRB spectra. Here, we develop a methodology to ``k-correct'' the implied prompt energy release of a GRB to a fixed co-moving bandpass. This allows us to homogenize the prompt energy release of 17 cosmological GRBs (using published redshifts, fluences, and spectra) to two common co-moving bandpasses: 20-2000 keV and 0.1 keV-10 MeV (``bolometric''). While the overall distribution of GRB energy releases does not change significantly by using a k-correction, we show that uncorrected energy estimates systematically undercounts the bolometric energy by ~5% to 600%, depending on the particular GRB. We find that the median bolometric isotropic-equivalent prompt energy release is 2.2 x 10^{53} erg with an r.m.s. scatter of 0.80 dex. The typical estimated uncertainty on a given k-corrected energy measurement is ~20%.Comment: Accepted to the Astronomical Journal. 21 pages (LaTeX) and 4 figure

    Radio Monitoring of the Tidal Disruption Event Swift J164449.3+573451. I. Jet Energetics and the Pristine Parsec-Scale Environment of a Supermassive Black Hole

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    We present continued radio observations of the tidal disruption event SwiftJ164449.3+573451 extending to \sim216 days after discovery. The data are part of a long-term program to monitor the expansion and energy scale of the relativistic outflow, and to trace the parsec-scale environment around a previously-dormant supermassive black hole (SMBH). The new observations reveal a significant change in the radio evolution starting at \sim1 month, with a brightening at all frequencies that requires an increase in the energy by about an order of magnitude, and an overall density profile around the SMBH of rho \propto r^{-3/2} (0.1-1.2 pc) with a significant flattening at r\sim0.4-0.6 pc. The increase in energy cannot be explained with continuous injection from an L \propto t^{-5/3} tail, which is observed in the X-rays. Instead, we conclude that the relativistic jet was launched with a wide range of Lorentz factors, obeying E(>Gamma) \propto Gamma^{-2.5}. The similar ratio of duration to dynamical timescale for Sw1644+57 and GRBs suggests that this result may be applicable to GRBs as well. The radial density profile may be indicative of Bondi accretion, with the inferred flattening at r\sim0.5 pc in good agreement with the Bondi radius for a \sim10^6 M_sun black hole. The density at \sim0.5 pc is about a factor of 30 times lower than inferred for the Milky Way galactic center, potentially due to a smaller number of mass-shedding massive stars. From our latest observations (\sim216 d) we find that the jet energy is E_{iso}\sim5x10^{53} erg (E_j\sim2.4x10^{51} erg for theta_j=0.1), the radius is r\sim1.2 pc, the Lorentz factor is Gamma\sim2.2, the ambient density is n\sim0.2 cm^{-3}, and the projected size is r_{proj}\sim25 microarcsec. Assuming no future changes in the observed evolution we predict that the radio emission from Sw1644+57 should be detectable with the EVLA for several decades, and will be resolvable with VLBI in a few years.Comment: Submitted to ApJ; 22 pages, 2 tables, 9 figure

    Diversi dalam Sistem Peradilan Pidana Anak di Indonesia

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    The criminal act that happens currently in the society is not done only by adult, even there is a trend that the person who did it was included in the children age. Legally, a call for a person who committed a crime that included in the children age is known as a child who has conflict with law. One of states efforts to protect the child who has conflict with law is by implementing the Diversion pattern, that is handling process to a child who has conflict with law is shifted from the formal to be a non-formal process. This research with the normative research type that is supported by the empirical data has purpose to investigate and study the Diversion ideas in the law protection to the child who has conflict with law, and further to find out the concrete implementation that is drafted in the Law of Children Jurisdiction System these days (Law No. 11 Year 2012) and the application by all law enforcer component and the related institutions that involves in the handling of the cases of child who has conflict with law in due process of law from the level of investigation, prosecution, court session and the development in the Prison for Children

    Chromatographic Identification of Leaf Color Characteristics on Fine-flavor and Bulk Cacao as Selection Indicator

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    A problem encountered in plant breeding process to determine bean color quality of fine-flavor cocoa is a long selection period. Preliminary results indicatedthat the fine-flavor cocoa has a low color reflectance than bulk cocoa. The objectiveof this study is to find more applicable and easier method to do the early detectionof fine-flavor cocoa on the breeding population. Detection of the leaf color haracteristics was done by chromatographic and spectrophotometry analysis. hromatographic analysis was carried out in Kaliwining Experimental Station, IndonesianCoffee and Cocoa Research Institute using complete random design consistedof two types of cocoa; fine-flavor (10 clones) and bulk cocoa (10 clones). pectrophotometric analysis was conducted at Ma Chung University, Malang, East Java.Four clones of bulk cocoa and six clones of fine flavor cocoa were used in thisanalysis. The results of the study showed that the flush color characteristics of thefine-flavor cocoa were different from the bulk cocoa characteristics as shown bythe differences in the value of L*, b* and anthocyanin content. Flush characteristic s ofthe fine-flavor cocoa had brighter color, more toward green with higher yellowlevel, while the bulk cocoa had darker flush, red and lower yellow level. Thecolor parameter of L* and b* had a higher genetic variation compared with theenvironment variation. However, the parameter a* had a higher environmental variation compared with genetic variation. Grouping of fine-flavor cocoa and bulk cocoacould be done through the detection of flush anthocyanin content, when tendencyof flush anthocyanin content on fine-flavor cocoa was lower than bulk cocoa.The detection of flush color particularly L* and b* parameters through hromatographic analysis and anthocyanin content through spectrophotometric analysismay be used as a criteria for selection the fine flavor cocoa on seedling phase

    Pengaruh Etika Auditor, Pengalaman Auditor, dan Gender terhadap Kemampuan Mendeteksi Praktik Akuntansi Kreatif (Studi pada Bpk RI Perwakilan Sumatera Selatan dan Kap di Sumatera Bagian Selatan)

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    This research aimed at investigating the effect of auditor ethics (independence, integrity, and objectivity), experience, and gender on the ability to detect creative accounting practices (at BPK RI Representative South Sumatra and KAP (Public Accounting Firms) Southern Sumatra). The research was conducted at BPK RI Representative South Sumatra and KAP Southern Sumatra with 129 respondents, 97 of whom were analyzed. Data were analyzed using multiple regression model. Results show that auditor ethics (independence, integrity, and objectivity), experience, and gender simultaneously affect the ability to detect creative accounting practices with (adjusted R square of 32%), while auditor\u27s independence, integrity, and experience have partial effect. However, objectivity and gender does not have significant effect on detecting creative accounting practices

    Formation of Kuiper Belt Binaries

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    The discovery that a substantial fraction of Kuiper Belt objects (KBOs) exists in binaries with wide separations and roughly equal masses, has motivated a variety of new theories explaining their formation. Goldreich et al. (2002) proposed two formation scenarios: In the first, a transient binary is formed, which becomes bound with the aid of dynamical friction from the sea of small bodies (L^2s mechanism); in the second, a binary is formed by three body gravitational deflection (L^3 mechanism). Here, we accurately calculate the L^2s and L^3 formation rates for sub-Hill velocities. While the L^2s formation rate is close to previous order of magnitude estimates, the L^3 formation rate is about a factor of 4 smaller. For sub-Hill KBO velocities (v << v_H) the ratio of the L^3 to the L^2s formation rate is 0.05 (v/v_H) independent of the small bodies' velocity dispersion, their surface density or their mutual collisions. For Super-Hill velocities (v >> v_H) the L^3 mechanism dominates over the L^2s mechanism. Binary formation via the L^3 mechanism competes with binary destruction by passing bodies. Given sufficient time, a statistical equilibrium abundance of binaries forms. We show that the frequency of long-lived transient binaries drops exponentially with the system's lifetime and that such transient binaries are not important for binary formation via the L^3 mechanism, contrary to Lee et al. (2007). For the L^2s mechanism we find that the typical time, transient binaries must last, to form Kuiper Belt binaries (KBBs) for a given strength of dynamical friction, D, increases only logarithmically with D. Longevity of transient binaries only becomes important for very weak dynamical friction (i.e. D \lesssim 0.002) and is most likely not crucial for KBB formation.Comment: 20 pages, 3 figures, Accepted for publication in ApJ, correction of minor typo
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