2,126 research outputs found

    OPTIMALISASI PERANGKAT PEMBELAJARAN MENGGUNAKAN MODEL INQUIRY LAB UNTUK MENINGKATKAN OSEAN DAN PEMAHAMAN KONSEP SISWA PADA MATERI FLUIDA STATIS

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    Berdasarkan PERMENDIKBUD No.81A tentang Impementasi Kurikulum 2013, proses pembelajaran langsung mewadahi siswa untuk mengembangkan pengetahuan dan keterampilan. Dalam pelaksanaannya kegiatan belajar yang dilakukan siswa adalah mengamati menanya mengumpulkan informasi, mengasosiasi, dan mengkomunikasikan. Pada penelitian ini kegiatan tersebut dinamakan ‘OSEAN’. Hasil studi pendahuluan menunjukkan, dengan metode ceramah kegiatan OSEAN siswa berurutan 76%, 17%, 29%, 26%, dan 30% dari jumlah siswa yang mengikuti pembelajaran, selain itu hanya 11% siswa yang mencapai KKM. Telah dilakukan Penelitian Tindakan Kelas (PTK) yang bertujuan untuk meningkatkan kegiatan ‘OSEAN’ dan pemahaman konsep siswa melalui optimalisasi perangkat pembelajaran menggunakan model inquiry lab. Untuk melihat kegiatan ‘OSEAN’ digunakan lembar observasi dan open guided inquiry worksheet, sedangkan pemahaman konsep dilihat dari hasil tes pemahaman konsep setiap pertemuan. Indikator keberhasilan PTK adalah (1) untuk kegiatan OSEAN siswa berturut-turut 85%,50%,50%,50%,50% dan 50% siswa tuntas dalam menyelesaikan masalah menggunakan metode ilmiah (2) untuk pemahaman konsep 80% siswa mencapai KKM. Setelah melakukan refleksi dan evaluasi pada siklus I dan II, pada siklus III, peneliti menekankan pada pendekatan ilmiah dan memberi penguatan konsep yang lebih mendalam pada akhir pembelajaran. Hasil yang diperoleh 100% siswa mencapai nilai di atas KKM. Kegiatan ‘OSEAN’ siswa dari hasil observasi selama proses pembelajaran yaitu 100%, 73%, 100%, 100%, 60% pada tahap verifikasi, sedangkan dari hasil open guided inquiry worksheet 100% siswa melakukan kegiatan ‘OSEAN’ dan 93,3% siswa tuntas menyelesaikan masalah menggunakan metode ilmiah. Pada siklus III semua indikator keberhasilan tercapai. Kata kunci : Kurikulum 2013, OSEAN, Pemahaman konsep, Inquiry Lab Based on Permendikbud No.81A about Implementation of Curriculum 2013, directly facilitate the students learning process to develop their knowledge and skills. In the implementation, learning activities of students is observing, asking, collecting information, associating, and communicating. In this study these activities are called 'OSEAN'. The results of a preliminary study suggests that OSEAN activities of student using lecture method is 76%, 17%, 29%, 26%, and 30% from all students who take the lessons, but only 11% of students who has achievement over the minimal passing criteria. A Classroom Action Research (CAR) has been done to increase the 'OSEAN' activities and students' concepts comprehension through optimization of learning tools using an inquiry lab model. Observation sheets and guided inquiry worksheets are used to observe the OSEAN activities. Concepts comprehension are seen from the results of concept comprehension tests of each meeting. Successful indicators of this CAR are (1) OSEAN activities of each student respectively are 85%, 50%, 50%, 50%, 50% and 50% of students are completed in solving problems using the scientific method (2) 80% of students have achievement over the minimal passing criteria. After some reflection and evaluation of first and second lesson, in the third lesson, the researcher emphasized the learning on the scientific approach and give a more deep concepts strengthening at the end of lesson. The results are 100% of students have achievement over the minimal passing criteria. From the observation, 'OSEAN' activities are 100%, 73%, 100%, 100%, 60% at the verification stage. From the open guided inquiry, 100% of students do 'OSEAN' and 93.3% students completely solve problems using the scientific method. In the third cycle all indicators are achieved. Keywords: Curriculum 2013, OSEAN, Concepts Comprehension, Inquiry La

    Partial radiogenic heat model for Earth revealed by geoneutrino measurements

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    The Earth has cooled since its formation, yet the decay of radiogenic isotopes, and in particular uranium, thorium and potassium, in the planet’s interior provides a continuing heat source. The current total heat flux from the Earth to space is 44:2±1.0 TW, but the relative contributions from residual primordial heat and radiogenic decay remain uncertain. However, radiogenic decay can be estimated from the flux of geoneutrinos, electrically neutral particles that are emitted during radioactive decay and can pass through the Earth virtually unaffected. Here we combine precise measurements of the geoneutrino flux from the Kamioka Liquid-Scintillator Antineutrino Detector, Japan, with existing measurements from the Borexino detector, Italy.We find that decay of uranium-238 and thorium-232 together contribute 20.0^(+8.8)_(-8.6)TW to Earth’s heat flux. The neutrinos emitted from the decay of potassium-40 are below the limits of detection in our experiments, but are known to contribute 4TW. Taken together, our observations indicate that heat from radioactive decay contributes about half of Earth’s total heat flux. We therefore conclude that Earth’s primordial heat supply has not yet been exhausted

    Constraints on θ_(13) from a three-flavor oscillation analysis of reactor antineutrinos at KamLAND

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    We present new constraints on the neutrino oscillation parameters Δm^2_(21), θ_(12), and θ_(13) from a three flavor analysis of solar and KamLAND data. The KamLAND data set includes data acquired following a radiopurity upgrade and amounts to a total exposure of 3.49 x 10^(32) target-proton-year. Under the assumption of CPT invariance, a two-flavor analysis (θ_(13) = 0) of the KamLAND and solar data yields the best-fit values tan^2θ_(12) = 0.444^(+0.036)_(-0.030) and Δm^2_(21) = 7.50^(+0.19)_(-0.20) x 10^(-5) eV^2; a three-flavor analysis with θ13 as a free parameter yields the best-fit values tan^2θ_(12) = 0.452^(+0.035)_(-0.033), Δm^2_(21) = 7.50^(+0.19)_(-0.20) x 10^(-5) eV^2, and sin^2θ_(13) = 0.020^(+0.016)_(-0.016). This θ_(13) interval is consistent with other recent work combining the CHOOZ, atmospheric and long-baseline accelerator experiments. We also present a new global θ_(13) analysis, incorporating the CHOOZ, atmospheric, and accelerator data, which indicates sin^2θ_(13) = 0.009^(+0.013)-_(0.007). A nonzero value is suggested, but only at the 79% C.L

    Propuesta para el manejo sostenible del turismo

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    This article analyzes the humpback whale watching activity in the area of Salinas. It examines the history, current situation and supporting industry. With this basis, we proceed to identify key actors and issues, after which it performs a SWOT analysis and impact analysis of regulations. After which ends with an agreement of partnership, recommendations for regulation, and a list of goo

    Emisión de acciones como una estrategia de financiamiento para las empresas que operan en el mercado ecuatoriano caso: empresa agrotropical

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    Unos de los principales problemas que tienen las empresas que operan en el mercado ecuatoriano, es la dificultad de obtener recursos financieros del sector bancario; pues, el costo en que estas incurren para obtener capital por medio de la banca es muy alto; esto ocasiona un estancamiento en el emprendimiento de nuevos proyectos, los mismos que ayudarían a fortalecer el aparato productivo del país. Esto se debe en gran parte a la falta de conocimiento de las diversas formas de financiamiento que existen en el país. El mercado de valores es un medio de captar capitales, interviniendo en este mercado se puede obtener varios beneficios como costos de captación menores a otras maneras de financiarse. Este fue el caso de la empresa a estudio Agrotropical, una compañía que se dedica al cultivo de cacao y teca, que pensado en expandir sus tierras necesitaba financiarse de la manera más eficiente. Luego de los análisis realizados en diferentes escenarios, se comprobó que la forma óptima de obtener recursos financieros es por medio de emitir acciones por medio del mercado de valores

    Modelização de separações por membrana através de métodos de refinamento de malha

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    Aplicou-se um modelo que conjuga a polarização da concentração e o transporte numa membrana para simular a ultrafiltração de soluções aquosas de PEG-3400. O problema incorpora o modelo de fricção binária desenvolvido a partir de uma modificação da equação de Maxwell-Stefan-Lightfoot. Desenvolveu-se um método numérico adaptativo eficiente para resolver simultaneamente as duas partes do modelo (camada de polarização e membrana). A resolução numérica do sistema algébrico-diferencial permitiu a ilustração adequada do fenómeno de rejeição aparente de soluto (em soluções aquosas de PEG-3400) assim como da queda de pressão em função do fluxo. Por outro lado, possibilitou a previsão adequada da influência de parâmetros físico-químicos e das condições de operação nesses fenómenos de rejeição, para além da correcta formação dos perfis de concentração e de fluxo quer na zona da camada de polarização como da membrana. A comparação com valores experimentais de ultrafiltração possibilita a validação do modelo no caso específico das soluções de PEG-3400. Os resultados de simulação dependem significativamente das características de resistência, Rm, da membrana que manifestam uma grande variabilidade de ensaio para ensaio e que influenciam o valor do coeficiente de equilíbrio, Keq
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