2,719 research outputs found

    Analisa Dan Penerapan Model Maintenance Quality Function Deployment (MQFD) Untuk Meningkatkan Kualitas Sistem Pemeliharaan Mesin Gilingan (Studi Kasus Pada PT.PG.X2 Malang)

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    Maintenance system is critical because if the maintenance goes well it will be able to guarantee the availability of the mechanical equipment so that the production system will running smoothly. One of the mechanical equipment that most important in the manufacturing especially in the sugar mill is the milling machine. The milling machine should always be in a condition that ready for use. In order to guarantee the availability of the machine, maintenance of a good strategy absolutely must be done. This research used MQFD method whereby this method is an integration between QFD and TPM method. According to Pramod et al., Merging the two methods are expected to improve the quality of maintenance as well as to accommodate the all costumer voices both internal customers and external customers as compared to existing methods of maintenance. The results of this study, it is known that the milling machine maintenance needs to be improved in order to improve the performance of milling machines. As the solution, the steps to be taken are Implementation of routine inspection, Train maintenance staff, Assessing and Improving awareness of the operator and machinist, Utilizing softwares to record and analyze machine components data, Execution Planned Component Replacement and cleaning the machine regularly

    EVALUASI PENGENDALIAN INTERN PENGADAAN BERAS PADA PERUSAHAAN UMUM BADAN URUSAN LOGISTIK KANTOR WILAYAH SULAWESI UTARA DAN GORONTALO

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    Perkembangan dunia semakin modern sehingga sangat membutuhkan pengendalian intern dalam perusahaan agar dapat berjalan sebagaimana mestinya. Perum Bulog Kanwil Sulawesi Utara dan Gorontalo dalam pengadaan harus meningkatkan pengendalian internal untuk mencapai tujuan. Penelitian ini bertujuan untuk pengendalian intern pengadaan beras Perum Bulog Kanwil Sulawesi Utara dan Gorontalo dengan COSO. Metode penelitian yang digunakan yaitu metode deskriptif kualitatif dengan menggunakan wawancara dan dokumentasi sebagai pengumpulan data. Hasil dari penelitian menunjukan bahwa kelima komponen pengendalian intern yang telah di tetapkan Perum Bulog Kanwil Sulawesi Utara dan Gorontalo sudah efektif dan sesuai dengan pengendalian intern COSO.Kata Kunci: Evaluasi, Pengendalian Intern, Pengadaan Beras

    Nonlinear coherent transport of waves in disordered media

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    We present a diagrammatic theory for coherent backscattering from disordered dilute media in the nonlinear regime. The approach is non-perturbative in the strength of the nonlinearity. We show that the coherent backscattering enhancement factor is strongly affected by the nonlinearity, and corroborate these results by numerical simulations. Our theory can be applied to several physical scenarios like scattering of light in nonlinear Kerr media, or propagation of matter waves in disordered potentials.Comment: 4 pages, 3 figure

    Evaluasi Pemungutan Bea Perolehan Hak Atas Tanah dan Bangunan (Bphtb) di Dinas Pendapatan, Pengelolaan Keuangan dan Aset Daerah (Dppkad) Kabupaten Halmahera Utara

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    Sesuai dengan peraturan Perundang-undangan yang berlaku tentang pemungutan BPHTB dan juga dalam hal pembangunan yang berkaitan dengan tanah dan bangunan di Kabupaten Halmahera Utara terus mengalami kemajuan. BPHTB menjadi pajak daerah yang berpotensi meningkatkan Pendapatan Asli Daerah, dan berpotensi meningkatkan local taxing power kabupaten dan kota. Tujuan penelitian ini adalah untuk mengetahui dan mengevaluasi pelaksanaan pemungutan BPHTB. Metode yang digunakan adalah penelitian deskriptif. Untuk memperoleh data yang diperlukan, penulis melakukan kegiatan pengumpulan data dengan cara wawancara, dokumentasi, dan observasi. Hasil penelitian terhadap evaluasi pemungutan BPHTB belum berjalan baik karena masih adanya satu prosedur yang tidak sesuai dengan peraturan yang ada. Kendala-kendala yang ditemui ada dua, yaitu: kendala yang berhubungan dengan Wajib Pajak dan kendala yang berhubungan dengan Sumber Daya Manusia yang masih kurang di bidang pendapatan. Dari segi perkembangan penerimaan mengalami fluktuasi. Hasil penelitian secara keseluruhan dari segi pemungutan BPHTB cukup baik karena ada satu prosedur yang tidak sesuai yaitu prosedur pembayaran, kendala yang ditemui beragam, dan perkembangan penerimaan berfluktuasi namun sudah mencapai 100% bahkan lebih. Sebaiknya pimpinan DPPKAD meningkatkan kualitas SDM melalui pendidikan dan pelatihan, sosialisasi, perekrutan juga kerjasama. Kata kunci: evaluasi, pemungutan, BPHTB, DPPKA

    Confirmation of the Luminous Blue Variable status of MWC 930

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    We present spectroscopic and photometric observations of the emission-line star MWC 930 (V446 Sct) during its long-term optical brightening in 2006--2013. Based on our earlier data we suggested that the object has features found in Luminous Blue Variables (LBV), such as a high luminosity (~3 10^5 Lsun, a low wind terminal velocity (~ 140 km/s), and a tendency to show strong brightness variations (~1 mag over 20 years). For the last ~7 years it has been exhibiting a continuous optical and near-IR brightening along with a change of the emission-line spectrum appearance and cooling of the star's photosphere. We present the object's VV--band light curve, analyze the spectral variations, and compare the observed properties with those of other recognized Galactic LBVs, such as AG Car and HR Car. Overall we conclude the MWC 930 is a bona fide Galactic LBV that is currently in the middle of an S Dor cycle.Comment: 12 pages, 7 figure

    Detection of orbital and superhump periods in Nova V2574 Ophiuchi (2004)

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    We present the results of 37 nights of CCD unfiltered photometry of nova V2574 Oph (2004) from 2004 and 2005. We find two periods of 0.14164 d (~3.40 h) and 0.14773 d (~3.55 h) in the 2005 data. The 2004 data show variability on a similar timescale, but no coherent periodicity was found. We suggest that the longer periodicity is the orbital period of the underlying binary system and that the shorter period represents a negative superhump. The 3.40 h period is about 4% shorter than the orbital period and obeys the relation between superhump period deficit and binary period. The detection of superhumps in the light curve is evidence of the presence of a precessing accretion disk in this binary system shortly after the nova outburst. From the maximum magnitude - rate of decline relation, we estimate the decay rate t_2 = 17+/-4 d and a maximum absolute visual magnitude of M_Vmax = -7.7+/-1.7 mag.Comment: 6 pages, 6 figures, 2 .sty files, AJ accepted, minor change to one of reference

    Evolution from protoplanetary to debris discs: The transition disc around HD 166191

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    HD 166191 has been identified by several studies as hosting a rare and extremely bright warm debris disc with an additional outer cool disc component. However, an alternative interpretation is that the star hosts a disc that is currently in transition between a full gas disc and a largely gas-free debris disc. With the help of new optical to mid-IR spectra and Herschel imaging, we argue that the latter interpretation is supported in several ways: i) we show that HD 166191 is co-moving with the ~4 Myr-old Herbig Ae star HD 163296, suggesting that the two have the same age, ii) the disc spectrum of HD 166191 is well matched by a standard radiative transfer model of a gaseous protoplanetary disc with an inner hole, and iii) the HD 166191 mid-IR silicate feature is more consistent with similarly primordial objects. We note some potential issues with the debris disc interpretation that should be considered for such extreme objects, whose lifetime at the current brightness is mush shorter than the stellar age, or in the case of the outer component requires a mass comparable to the solid component of the Solar nebula. These aspects individually and collectively argue that HD 166191 is a 4-5 Myr old star that hosts a gaseous transition disc. Though it does not argue in favour of either scenario, we find strong evidence for 3-5 um disc variability. We place HD 166191 in context with discs at different evolutionary stages, showing that it is a potentially important object for understanding the protoplanetary to debris disc transition.Comment: accepted to MNRAS, fixed typos in abstract and axis labe

    Brain Endothelial Erythrophagocytosis and Hemoglobin Transmigration Across Brain Endothelium: Implications for Pathogenesis of Cerebral Microbleeds

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    Peripheral endothelial cells are capable of erythrophagocytosis, but data on brain endothelial erythrophagocytosis are limited. We studied the relationship between brain endothelial erythrophagocytosis and cerebral microhemorrhage, the pathological substrate of MRI-demonstrable cerebral microbleeds. To demonstrate the erythrophagocytic capability of the brain endothelium, we studied the interactions between brain endothelial cells and red blood cells exposed to oxidative stress in vitro, and developed a new in vitro cerebral microbleeds model to study the subsequent passage of hemoglobin across the brain endothelial monolayer. Using multiple approaches, our results show marked brain endothelial erythrophagocytosis of red blood cells exposed to oxidative stress compared with control red blood cells in vitro. This brain endothelial erythrophagocytosis was accompanied by passage of hemoglobin across the brain endothelial monolayer with unaltered monolayer integrity. In vivo and confocal fluorescence microscopy studies confirmed the extravasation of RBC exposed to oxidative stress across brain endothelium. These findings, demonstrating erythrophagocytosis mediated by the brain endothelial monolayer and the subsequent passage of iron-rich hemoglobin in vitro and RBC in vivo, may have implications for elucidating mechanisms involved in the development of cerebral microbleeds that are not dependent on disruption of the microvasculature

    The long-term evolution of the spin, pulse shape, and orbit of the accretion-powered millisecond pulsar SAX J1808.4-3658

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    We present a 7 yr timing study of the 2.5 ms X-ray pulsar SAX J1808.4-3658, an X-ray transient with a recurrence time of ~2 yr, using data from the Rossi X-ray Timing Explorer covering 4 transient outbursts (1998-2005). We verify that the 401 Hz pulsation traces the spin frequency fundamental and not a harmonic. Substantial pulse shape variability, both stochastic and systematic, was observed during each outburst. Analysis of the systematic pulse shape changes suggests that, as an outburst dims, the X-ray "hot spot" on the pulsar surface drifts longitudinally and a second hot spot may appear. The overall pulse shape variability limits the ability to measure spin frequency evolution within a given X-ray outburst (and calls previous nudot measurements of this source into question), with typical upper limits of |nudot| < 2.5x10^{-14} Hz/s (2 sigma). However, combining data from all the outbursts shows with high (6 sigma) significance that the pulsar is undergoing long-term spin down at a rate nudot = (-5.6+/-2.0)x10^{-16} Hz/s, with most of the spin evolution occurring during X-ray quiescence. We discuss the possible contributions of magnetic propeller torques, magnetic dipole radiation, and gravitational radiation to the measured spin down, setting an upper limit of B < 1.5x10^8 G for the pulsar's surface dipole magnetic field and and Q/I < 5x10^{-9} for the fractional mass quadrupole moment. We also measured an orbital period derivative of Pdot = (3.5+/-0.2)x10^{-12} s/s. This surprising large Pdot is reminiscent of the large and quasi-cyclic orbital period variation observed in the so-called "black widow" millisecond radio pulsars, supporting speculation that SAX J1808.4-3658 may turn on as a radio pulsar during quiescence. In an appendix we derive an improved (0.15 arcsec) source position from optical data.Comment: 22 pages, 10 figures; accepted for publication in Ap
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