10 research outputs found

    The Influence of the Principal’s Leadership Style and Physical Work Environment on Teacher’s Performance

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    This study aims to determine and analyze (1) the influence of the principal’s leadership style on teacher’s performance; (2) the influence of the work environment on teacher’s performance; and (3) the influence of leadership style and work environment partially or jointly on teacher’s performance. This research is a quantitative research with partial correlation method. This research was conducted at SMK Negeri Ilir Barat I Palembang with 126 teachers as respondents. Data collection techniques using questionnaires and documentation. Validity test uses construction validity and content validity. While the reliability test uses Cronbachh’s Alpha. The analysis prerequisite test used the normality test, linearity test, heteroscedasticity test, and multilinearity test, and the data were analyzed using simple regression and multiple regression techniques. The results showed that: (1) there was a positive and significant effect of the principal’s leadership style on the performance of State Vocational High School teachers in Ilir Barat I Palembang with a presentation of 22%; (2) There is a positive and significant effect of the work environment on the performance of State Vocational High School teachers in Ilir Barat I District, Palembang with a presentation of 19.4%; and (3) there is a positive and significant influence of the principal’s leadership style with the work environment on teacher’s performance. State Vocational High School in Ilir Barat I District, Palembang with a presentation of 21.8% while 78.2% was determined by other factors not included in this study

    Penggunaan Media Pembelajaran Aplikasi Quizizz pada Masa Pandemi Di SMK N 5 Palembang

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    This article aims to illustrate how to use Quizizz as a learning tool. This article is a study of the literature, including references to books, journals, and Internet postings. This article explores how the Quizizz application can generate creative, innovative, and interesting learning media, and why educators should use it as a learning tool, particularly during the pandemic of Covid-19.Tujuan artikel ini adalah untuk menjelaskan cara menggunakan Quizizz sebagai media pembelajaran. Artikel ini merupakan tinjauan pustaka, dikutip dari berbagai sumber, termasuk buku, jurnal, dan postingan di internet. Bagaimana aplikasi Quizizz dapat menghasilkan media pembelajaran yang kreatif, inovatif dan menarik, sehingga sangat disarankan bagi para pendidik untuk memanfaatkannya sebagai media pembelajaran, terutama pada saat pandemi terjadi juga disajikan di dalam artikel ini

    The Orange Tuff : a Late Pleistocene tephra-fall deposit emplaced by a VEI 5 silicic Plinian eruption in West Java, Indonesia

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    A VEI 5 dacite eruption emplaced the Orange Tuff about between 34.3 cal kBP and 17.2 cal kBP. Gunung Salak is the unit’s source and the Orange Tuff represents the most recent such eruption from any of the volcanoes southwest of Bogor, Indonesia. The Orange Tuff is the region’s first such documented tephra-fall deposit whose characteristics and phenocryst geochemistry make it readily identifiable over at least 1250 km2. Magnetite compositions and temperature and fO2 estimates inferred from Fe-Ti oxide compositions are particularly useful for identifying the unit. Deposit characteristics suggest that the eruption lasted 1–11 h with mass eruption rates of 1.0–8.3 × 108 kg/s and a column height of 31–40 km. The eruption’s column height and the deposit’s 2.5–11 km3 volume suggest that the unit was dispersed over a much wider area than mapped. The unit is a marker bed throughout its mapped distribution and has potential to be applied over a much broader area as a regional marker bed. The large population and infrastructure proximal to Salak suggest that the unit should be considered in hazards assessments despite its age and the lack of subsequent similar eruptions.Published versio

    Recent explosive eruptions and volcano hazards at Soputan volcano-a basalt stratovolcano in north Sulawesi, Indonesia

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    Soputan is a high-alumina basalt stratovolcano located in the active North Sulawesi-Sangihe Islands magmatic arc. Although immediately adjacent to the still geothermally active Quaternary Tondono Caldera, Soputan\u27s magmas are geochemically distinct from those of the caldera and from other magmas in the arc. Unusual for a basalt volcano, Soputan produces summit lava domes and explosive eruptions with high-altitude ash plumes and pyroclastic flows-eight explosive eruptions during the period 2003-2011. Our field observations, remote sensing, gas emission, seismic, and petrologic analyses indicate that Soputan is an open-vent-type volcano that taps basalt magma derived from the arc-mantle wedge, accumulated and fractionated in a deep-crustal reservoir and transported slowly or staged at shallow levels prior to eruption. A combination of high phenocryst content, extensive microlite crystallization and separation of a gas phase at shallow levels results in a highly viscous basalt magma and explosive eruptive style. The open-vent structure and frequent eruptions indicate that Soputan will likely erupt again in the next decade, perhaps repeatedly. Explosive eruptions in the Volcano Explosivity Index (VEI) 2-3 range and lava dome growth are most probable, with a small chance of larger VEI 4 eruptions. A rapid ramp up in seismicity preceding the recent eruptions suggests that future eruptions may have no more than a few days of seismic warning. Risk to population in the region is currently greatest for villages located on the southern and western flanks of the volcano where flow deposits are directed by topography. In addition, Soputan\u27s explosive eruptions produce high-altitude ash clouds that pose a risk to air traffic in the region. © 2012 Springer-Verlag

    Extending the long-term record of volcanic SO 2

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    Uninterrupted, global space-based monitoring of volcanic sulfur dioxide (SO2) emissions is critical for climate modeling and aviation hazard mitigation. We report the first volcanic SO2 measurements using ultraviolet (UV) Ozone Mapping and Profiler Suite (OMPS) nadir mapper data. OMPS was launched on the Suomi National Polar-orbiting Partnership satellite in October 2011. We demonstrate the sensitivity of OMPS SO2 measurements by quantifying SO2 emissions from the modest eruption of Paluweh volcano (Indonesia) in February 2013 and tracking the dispersion of the volcanic SO2 cloud. The OMPS SO2 retrievals are validated using Ozone Monitoring Instrument and Atmospheric Infrared Sounder measurements. The results confirm the ability of OMPS to extend the long-term record of volcanic SO2 emissions based on UV satellite observations. We also show that the Paluweh volcanic SO2 reached the lower stratosphere, further demonstrating the impact of small tropical volcanic eruptions on stratospheric aerosol optical depth and climate

    Field survey and numerical modelling of the December 22, 2018 Anak Krakatau tsunami

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    Summarization: On December 22, 2018, the eruption and flank collapse of the Anak Krakatau volcano generated a tsunami in the Sunda Strait causing catastrophic damage to uninhabited coastlines proximal to the source. Along the heavily populated shores of Banten and Lampung provinces in Java and Sumatra, tsunami waves caused severe damage, extensive inundation and more than 430 deaths. An international tsunami survey team (ITST) deployed 6 weeks after the event documented the tsunami effects including runup heights, flow depths and inundation distances, as well as sediment deposition patterns and impacts on infrastructure and the natural environment. The team also interviewed numerous eyewitnesses and educated residents about tsunami hazards. This ITST was the first to visit and document the extreme tsunami effects on the small islands in the Sunda Strait closest to Anak Krakatau (Rakata, Panjang, Sertung, Sebesi and Panaitan). Along the steep slopes of Rakata and Sertung islands, located less than 5 km from and facing directly towards the southwest flank of Anak Krakatau, all of the dense coastal vegetation was stripped to bare earth up to elevations of more than 80 m, while on the northeast tip of Sertung Island, facing away from the source, a single tree remained standing after flow depths of  > 11 m above ground struck there. The runup distributions on the islands encircling Anak Krakatau highlight the directivity of the tsunami source suggesting that the collapse occurred towards the southwest. This manifested as tsunami runup of  10 m that stripped away coastal forests to bare rock for up to 400 m inland in the Ujung Kulon National Park, located 50 km to the south-southwest. Inundation and damage were mostly limited to within 400 m of the shoreline, likely the result of the relatively short wavelengths caused by the landslide generated tsunami. A significant variation in tsunami impact was observed along the shorelines of the Sunda Strait, with runup heights rapidly decreasing with distance from the inferred tsunami source. To model the event we applied a hot-start initial condition that roughly reproduced the measured tsunami runup heights along Rakata and Sertung. The waveforms were then propagated through the Sunda Straight using a Boussinesq-type wave model. The results showed a good fit to the observed heights along the Java and Sumatra coastlines, the northern coast of Panaitan Island and Ujung Kulon Nation Park. The model also produced an acceptable fit to the observed amplitudes at tide gauges. Despite the regional volcanic and tsunamigenic history of the region, and 6-months of eruptive activity prior to the event, the tsunami largely caught the local population off guard. This further highlights the need for community-based education and awareness programs as essential to save lives in locales at risk from locally generated tsunamis.Presented on: Pure and Applied Geophysic

    Multi-decadal satellite measurements of global volcanic degassing

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    © 2016 The Authors. Satellite instruments have been providing measurements of global volcanic emissions of sulfur dioxide (SO2) since 1978, based on observations in the ultraviolet (UV), infrared (IR) and microwave spectral bands. We review recent advances in satellite remote sensing of volcanic gases, focusing on increased instrument sensitivity to tropospheric SO2 emissions and techniques to determine volcanic plume altitude. A synthesis of ~36 years of global UV, IR and microwave satellite measurements yields an updated assessment of the volcanic SO2 flux to the upper troposphere and lower stratosphere (UTLS) between 1978 and 2014 (~1-Tg/yr). The present availability of multiple UV and IR satellite SO2 products provides increased confidence in calculated SO2 loadings for many eruptions. We examine the temporal and latitudinal distribution of volcanic SO2 emissions and reassess the relationship between eruptive SO2 discharge and eruption magnitude, finding a first-order correlation between SO2 emission and volcanic explosivity index (VEI), but with significant scatter. Based on the observed SO2-VEI relation, we estimate the fraction of eruptive SO2 emissions released by the smallest eruptions (~0.48 Tg/yr), which is not recorded by satellite observations. A detailed breakdown of the sources of measured SO2 emissions reveals intuitively expected correlations between eruption frequency, SO2 loading and volcanic degassing style. We discuss new constraints on e-folding times for SO2 removal in volcanic plumes, and highlight recent measurements of volcanic hydrogen chloride (HCl) injections into the UTLS. An analysis of passive volcanic emissions of SO2 detected in Ozone Monitoring Instrument (OMI) SO2 data since 2004 provides new insight into the location and stability of the dominant sources of volcanic SO2 over the past decade. Since volcanic SO2 emissions constitute a random, highly variable perturbation to the atmosphere-climate system, continued monitoring of volcanic SO2 emissions from space by multiple UV and IR instruments to extend the current multi-decadal record is essential, and near-global, geostationary measurements of SO2 may be available by the end of the current decade

    Multi-decadal satellite measurements of global volcanic degassing

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