Penerapan Metode Drill untuk Meningkatkan Hasil Belajar Matematika Siswa Kelas V Sdn 001 Japura Kecamatan Lirik Kabupaten Indragiri Hulu

The background of this research is based on the fact that happened in class V SD Negeri 001 Japura, who showed symptoms of low ability to absorb students in math. The problem of this research is "Does the application of methods drill can improve learning outcomes math class V students of SD Negeri 001 Japura District of Lirik Indragiri Hulu?" The purpose of this research is to improve learning outcomes math class V students through the application of methods drill in SD Negeri 001 Japura Lirik Indragiri Hulu subdistrict. This study took place in class V SD Negeri 001 Japura District of Lirik and executed April 13 until April 29th 2016, with the number of subjects as many as 20 people consisting of 11 girls and 9 boys. This research is a classroom action research conducted in two cycles. Based on the results the percentage learning outcomes on the basis of the average score increased in Deuteronomy 60 Daily I became 72, with an increase of 20%. In Deuteronomy Daily II increased to 80 with an increase of 11.1%. Then of completeness individual and classical, in the first cycle the number of students who pass as many as 11 people of 55% and an incomplete 9 by 45%, in the second cycle the number of students who completed 18 of 90%, while the incomplete 2 of 10%. From these results demonstrate the applicability of the drill method can improve learning outcomes in mathematics V SDN 001 Japura District of Indragiri Hulu Lirik academic year 2015/2016

Pengembangan Indeks Kualitas Air sebagai Alternatif Penilaian Kualitas Air Sungai

Pengembangan Indeks Kualitas Air (IKA) merupakan proses lanjutan dari penyusunan IKA yang dilakukan Pusat Penelitian dan Pengembangan Kualitas dan Laboratorium Lingkungan (P3KLL) pada tahun 2016. Pengembangan IKA dilakukan melalui verifikasi terhadap komponen penyusun IKA yang meliputi kurva sub indeks, pembobotan parameter, dan verifikasi lapangan terhadap hasil formulasi IKA. Verifikasi lapangan dilakukan pada delapan lokasi di Sungai Ciliwung. Hasil verifikasi lapangan menunjukkan bahwa nilai IKA yang diperoleh dari hasil pengujian kualitas air di laboratorium dan hasil verifikasi lapangan oleh panelis pada waktu bersamaan menunjukkan nilai yang tidak berbeda nyata, sehingga rumusan IKA yang telah dikembangkan sesuai digunakan untuk penilaian Sungai Ciliwung. Nilai IKA dikembangkan menjadi enam kriteria yaitu sangat baik (100 ≤ I > 90), baik (90 ≤ I ≥ 80) cukup baik (80 < I ≥ 70), sedang (70 < I ≥ 51), marginal (51< I ≥ 36), dan buruk (36 < I ≥ 0). Hasil aplikasi IKA menunjukkan bahwa salah satu sumber mata air Sungai Ciliwung di wilayah yang berada di lereng Gunung Pangrango menpunyai nilai 91 dengan kriteria sangat bagus. Sungai Condet sebagai salah satu anak sungai Ciliwung dengan sumber pencemar domestik yang tinggi berada pada nilai 35.5 dengan kriteria buruk. Enam lokasi Sungai Ciliwung lainya berada pada kriteria marginal sampai baik. Rumusan IKA yang telah diperoleh dapat diaplikasikan untuk instrumen penilaian sungai dan hasilnya dapat dimanfatkan untuk perencanaan dan evaluasi pengendalian pencemaran air sungai

The late stages of evolution of helium star-neutron star binaries and the formation of double neutron star systems

With a view to understanding the formation of double neutron-stars (DNS), we investigate the late stages of evolution of helium stars with masses of 2.8 - 6.4 Msun in binary systems with a 1.4 Msun neutron-star companion. We found that mass transfer from 2.8 - 3.3 Msun helium stars and from 3.3 - 3.8 Msun in very close orbits (P_orb > 0.25d) will end up in a common-envelope (CE) and spiral-in phase due to the development of a convective helium envelope. If the neutron star has sufficient time to complete the spiraling-in process before the core collapses, the system will produce very tight DNSs (P_orb ~ 0.01d) with a merger timescale of the order of 1 Myr or less. These systems would have important consequences for the detection rate of GWR and for the understanding of GRB progenitors. On the other hand, if the time left until the explosion is shorter than the orbital-decay timescale, the system will undergo a SN explosion during the CE phase. Helium stars with masses 3.3 - 3.8 Msun in wider orbits (P_orb > 0.25d) and those more massive than 3.8 Msun do not go through CE evolution. The remnants of these massive helium stars are DNSs with periods in the range of 0.1 - 1 d. This suggests that this range of mass includes the progenitors of the galactic DNSs with close orbits (B1913+16 and B1534+12). A minimum kick velocity of 70 km/s and 0 km/s (for B1913+16 and B1534+12, respectively) must have been imparted at the birth of the pulsar's companion. The DNSs with wider orbits (J1518+4904 and probably J1811-1736) are produced from helium star-neutron star binaries which avoid RLOF, with the helium star more massive than 2.5 Msun. For these systems the minimum kick velocities are 50 km/s and 10 km/s (for J1518+4904 and J1811-1736, respectively).Comment: 16 pages, latex, 12 figures, accepted for publication in MNRA

The evolution of naked helium stars with a neutron-star companion in close binary systems

The evolution of helium stars with masses of 1.5 - 6.7 M_sun in binary systems with a 1.4 M_sun neutron-star companion is presented. Such systems are assumed to be the remnants of Be/X-ray binaries with B-star masses in the range of 8 - 20 M_sun which underwent a case B or case C mass transfer and survived the common-envelope and spiral-in process. The orbital period is chosen such that the helium star fills its Roche lobe before the ignition of carbon in the centre. We distinguish case BA (in which mass transfer is initiated during helium core burning) from case BB (onset of Roche-lobe overflow occurs after helium core burning is terminated, but before the ignition of carbon). We found that the remnants of case BA mass transfer from 1.5 - 2.9 M_sun helium stars are heavy CO white dwarfs. This implies that a star initially as massive as 12 M_sun is able to become a white dwarf. CO white dwarfs are also produced from case BB mass transfer from 1.5 - 1.8 M_sun helium stars, while ONe white dwarfs are formed from 2.1 - 2.5 M_sun helium stars. Case BB mass transfer from more-massive helium stars with a neutron-star companion will produce a double neutron-star binary. We are able to distinguish the progenitors of type Ib supernovae (as the high-mass helium stars or systems in wide orbits) from those of type Ic supernovae (as the lower-mass helium stars or systems in close orbits). Finally, we derive a "zone of avoidance" in the helium star mass vs. initial orbital period diagram for producing neutron stars from helium stars.Comment: 16 pages, latex, 11 figures, accepted for publication in MNRA

Grip force measurement of soft- Actuated finger exoskeleton

Over recent years, the reseach in the field of soft actuation has been extensively increased for achieving more complex motion path with smooth, high flexible movement and high generated force at minimum operating pressure. This paper presents the study on gripping force capability of soft actuators applied on glove-type finger exoskeleton, developed in motivation to assist individuals having weak finger gripping ability in their rehabilitation exercise towards hand function restoration. The exoskeleton utilizes five cylindrical shaped pneumatic bending actuators developed in the lab, which use fiber reinforcement as a cause of bending motion that drive finger’s flexion movement. Four right-handed healthy volunteers simulated paralysis participated in the study. At 200kPa safe operating pressure, the soft exoskeleton worn by the subjects demonstrates the ability to provide adequate grip force. The grip force generated from exoskeleton worn on passive right hand is 4.66 ± 0.2 N and 3.61± 0.2 N from passive left hand, both higher than the minimum grip forces measured to hold the Hand Dynamometer of 240 g. It shows good potential to be used as a finger rehabilitation assist device

The Galactic Population of Low- and Intermediate-Mass X-ray Binaries

(abridged) We present the first study that combines binary population synthesis in the Galactic disk and detailed evolutionary calculations of low- and intermediate-mass X-ray binaries (L/IMXBs). We show that the formation probability of IMXBs with initial donor masses of 1.5--4 Msun is typically >~5 times higher than that of standard LMXBs, and suggest that the majority of the observed systems may have descended from IMXBs. Distributions at the current epoch of the orbital periods, donor masses, and mass accretion rates have been computed, as have orbital-period distributions of BMPs. Several significant discrepancies between the theoretical and observed distributions are discussed. The orbital-period distribution of observed BMPs strongly favors cases where the envelope of the neutron-star progenitor is more easily ejected during the common-envelope phase. However, this leads to a >~100-fold overproduction of the theoretical number of luminous X-ray sources relative to the total observed number of LMXBs. X-ray irradiation of the donor star may result in a dramatic reduction in the X-ray active lifetime of L/IMXBs, thus possibly resolving the overproduction problem, as well as the long-standing BMP/LMXB birthrate problem.Comment: 12 pages, emulateapj, submitted to Ap