8,559,113 research outputs found

    Non-LTE line formation for Pr II and Pr III in A and Ap stars

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    Non-LTE line formation for Pr II and Pr III is considered through a range of effective temperatures between 7250 K and 9500 K. A comprehensive model atom for Pr II/III is based on the measured and the predicted energy levels, in total, 6708 levels of Pr II and Pr III. We describe calculations of the Pr II energy levels and oscillator strengths for the transitions in Pr II and Pr III. The influence of departures from LTE on Pr abundance determinations is evaluated. At Teff >= 8000 K departures from LTE lead to overionization of Pr II and to systematically depleted total absorption in the line and positive abundance corrections. At the lower temperatures, different lines of Pr II may be either weakened or amplified depending on the line strength. The non-LTE effects strengthen the Pr III lines and lead to negative abundance corrections. Non-LTE corrections grow with effective temperature for the Pr II lines, and, in contrast, they decline for the Pr III lines. The Pr II/III model atom is applied to determine the Pr abundance in the atmosphere of the roAp star HD 24712 from the lines of two ionization stages. In the chemically uniform atmosphere with [Pr/H] = 3, the departures from LTE may explain only small part (0.3 dex) of the difference between the LTE abundances derived from the Pr II and Pr III lines (2 dex). We find that the lines of both ionization stages are described for the vertical distribution of the praseodymium where the Pr enriched layer with [Pr/H] > 4 exists in the outer atmosphere at log tau_5000 < -4. The departures from LTE for Pr II/III are strong in the stratified atmosphere and have the opposite sign for the Pr II and Pr III lines. Using the revised partition function of Pr II and experimental transition probabilities, we determine the solar non-LTE abundance of Pr as log (Pr/H) = -11.15\pm0.08.Comment: 17 pages, 4 tables, 11 figures, accepted for publication in A&

    HUBUNGAN ANTARA DISIPLIN BELAJAR SISWA DENGAN HASIL BELAJAR IPA KELAS IV SD DI KELURAHAN CIBUBUR JAKARTA TIMUR

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    Penelitian korelasi ini bertujuan untuk mengetahui hubungan antara disiplin belajar siswa dengan hasil belajar IPA kelas IV SD di Kelurahan Cibubur Jakarta Timur. Sampel dalam penelitian ini adalah siswa kelas IV SDN Cibubur 09 Pagi dan SDN Cibubur 10 Pagi Kelurahan Cibubur Jakarta Timur sebanyak 70 siswa. pengambilan sampel menggunakan teknik cluster simple random sampling. Metode yang digunakan adalah metode penelitian kuantitatif dengan teknik korelasional. Pengumpulan data dilakukan dengan menggunakan angket dan tes hasil belajar IPA dan dianalisis dengan menggunakan Uji-t. Hasil penelitian menunjukkan bahwa disiplin belajar siswa berhubungan positif dengan hasil belajar IPA kelas IV SD dengan thitung = 8.555 > 1.995 = ttabel. Hasil ini menunjukkan bahwa disiplin belajar siswa dapat dijadikan sebagai salah satu upaya untuk meningkatkan hasil belajar IPA di kelas IV SD. Oleh sebab itu, guru perlu mengajarkan disiplin belajar kepada siswa di kelas sehingga dapat mengubah perilaku siswa dalam belajar sehingga dapat meningkatkan hasil belajar IPA siswa kelas IV SD

    _Limusaurus_ and bird digit identity

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    _Limusaurus_ is a remarkable herbivorous ceratosaur unique among theropods in having digits II, III and IV, with only a small metacarpal vestige of digit I. This raises interesting questions regarding the controversial identity of avian wing digits. The early tetanuran ancestors of birds had tridactyl hands with digital morphologies corresponding to digits I, II &#x26; III of other dinosaurs. In bird embryos, however, the pattern of cartilage formation indicates that their digits develop from positions that become digits II, III, &#x26; IV in other amniotes. _Limusaurus_ has been argued to provide evidence that the digits of tetanurans, currently considered to be I, II and III, may actually be digits II, III, &#x26; IV, thus explaining the embryological position of bird wing digits. However, morphology and gene expression of the anterior bird wing digit specifically resemble digit I, not II, of other amniotes. We argue that digit I loss in _Limusaurus_ is derived and thus irrelevant to understanding the development of the bird wing

    PENIMBANG BERAT DAN PENGUKUR PANJANG BADAN BAYI MENGGUNAKAN RFID BERBASIS ARDUINO

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    Penelitian ini bertujuan untuk merancang, mendesain dan membangun sistem penimbang bayi menggunakan RFID berbasis arduino. Penelitian dilaksanakan di Laboratorium Instrumentasi Fakultas Teknik Universitas Negeri Jakarta pada bulan Januari-Mei 2017. Metode yang digunakan dalam penelitian kali ini adalah metode rekayasa teknik yaitu membuat rancangan alat serta melakukan uji coba berupa program yang kemudian akan diterapkan pada rancang bangun penimbang bayi menggunakan Arduino Uno sebagai mikrokontroller, sebuah load cell yang digunakan sebagai sensor beratnya, sebuah DFPlayer sebagai modul MP3 yang terhubung dengan speaker sehingga dapat mengeluarkan suara yang sesuai dengan berat bayi, serta dua buah sensor ultrasonic yang digunakan untuk mengukur panjang badan bayi. Kemudian, berat, panjang bayi, serta grafik pertumbuhan bayi ditampilkan melalui laptop atau komputer. Berdasarkan hasil pengujian secara keseluruhan yang telah dilakukan, diketahui bahwa rancang bangun penimbang bayi menggunakan RFID berbasis arduino dapat mengukur berat dari 1 Kg sampai dengan 30 Kg dan panjang badan bayi yang dapat diukur maksimal adalah 88 Cm, kecepatan penimbang berat dan pengukur panjang badan bayi menggunakan RFID berbasis arduino menimbang bayi adalah 1 detik, dan juga mengeluarkan suara berat badan bayi sesuai dengan berat badan yang ditampilkan. penimbang berat dan pengukur panjang badan bayi menggunakan RFID berbasis arduino juga dapat mengamati pertumbuhan bayi dengan melihat grafik yang ada pada tampilan di laptop atau komputer. This research is aimed to design and build a weight measurement system for infant by using arduino based RFID. This research was conducted in Instrument Labotary of Technic Faculty at State University of Jakarta from January to May, 2017. The method used in this research is Enginering technic that was happened by designing the tool and made a test in a form of programe that was being applied to the infant weight measurement tool using Arduino Uno as the micro controller, a load cell as the weight sensor, a DFPlayer as MP3 module that linked to the speaker to give an audio output of the infant's weight, and two ultrasonic sensor that aimed to measure the body length of infant. As a result, the weight, lenghth of the body as well as the growth chart of the infant being cheked was displayed on laptop or computer screen. Based on the results of the overall testing that has been done, it is known that the design of the baby weighing using arduino-based RFID can measure the weight from 1 Kg to 30 Kg and the maximum measurable baby's length is 88 Cm, Weighing Weight and Infant Body Gauges Using Arduino Based RFID weigh the baby is 1 second, And also sounds the baby's weight according to the weight shown. Weighing Weight and Infant Body Gauges Using Arduino Based RFID can also observe the growth of the baby by looking at the graphics that are on display on a laptop or computer
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