Measurement of dimensions and alignment with optical instruments

Course, as contained in manual, encompasses principles involved in determining and applying proper optical tooling devices to fulfill precise measuring requirements

UJI KESESUAIAN JUMLAH LEUKOSIT URINE METODE CARIK CELUP DENGAN KAMAR HITUNG SHIH-YUNG PADA PASIEN SUSPEK INFEKSI SALURAN KEMIH

Pendahuluan: Infeksi saluran kemih merupakan salah satu penyakit infeksi yang sering ditemukan pada anak. Penentuan jumlah leukosit urine dengan metode carik celup merupakan metode paling umum dan praktis, namun presisi dan akurasinya sangat dipengaruhi banyak faktor terutama pengumpulan urine pada bayi. Pemeriksaan sedimen urine metode Shih-Yung diharapkan memiliki ketelitian dan ketepatan yang lebih baik dibandingkan dengan metode carik celup. Tujuan penelitian untuk mengetahui tingkat kesesuaian antara pemeriksaan jumlah leukosit urine antara metode carik celup dengan kamar hitung Shih-Yung pada pasien suspek infeksi saluran kemih di RSUP Dr. M. Djamil Padang. Metode: Penelitian observasional analitik dengan rancangan potong lintang dilakukan terhadap 28 orang pasien yang didiagnosis suspek infeksi saluran kemih oleh klinisi dan melakukan pemeriksaan leukosit urine di Laboratorium sentral RSUP Dr. M. Djamil Padang dari bulan September 2018 sampai dengan Juli 2019. Pemeriksaan leukosit urin menggunakan carik celup dan kamar hitung Shih-Yung. Hasil dianalisis dengan uji kesesuaian menggunakan nilai Kappa. Kemaknaan statistik ditentukan jika p<0,05. Hasil: Subjek penelitian berjumlah 28 orang. Rerata umur subyek penelitian adalah 6,7 ± 5,7 tahun. Jenis kelamin subyek penelitian terdiri dari 14 (50%) orang laki-laki dan 14 (50%) orang perempuan. Uji kesesuaian antara kamar hitung Shih-Yung dan carik celup didapatkan nilai kappa 0,868 dengan interpretasi baik sekali dan bermakna secara statistik (p<0,05). Simpulan: Terdapat kesesuaian jumlah leukosit urine antara carik celup dengan kamar hitung Shih-Yung pada pasien suspek infeksi saluran kemih

Three dimensional particle-in-cell simulation of particle acceleration by circularly polarised inertial Alfven waves in a transversely inhomogeneous plasma

The process of particle acceleration by left-hand, circularly polarised inertial Alfven waves (IAW) in a transversely inhomogeneous plasma is studied using 3D particle-in-cell simulation. A cylindrical tube with, transverse to the background magnetic field, inhomogeneity scale of the order of ion inertial length is considered on which IAWs with frequency $0.3 \omega_{ci}$ are launched that are allowed to develop three wavelength. As a result time-varying parallel electric fields are generated in the density gradient regions which accelerate electrons in the parallel to magnetic field direction. Driven perpendicular electric field of IAWs also heats ions in the transverse direction. Such numerical setup is relevant for solar flaring loops and earth auroral zone. This first, 3D, fully-kinetic simulation demonstrates electron acceleration efficiency in the density inhomogeneity regions, along the magnetic field, of the order of 45% and ion heating, in the transverse to the magnetic field direction, of 75%. The latter is a factor of two times higher than the previous 2.5D analogous study and is in accordance with solar flare particle acceleration observations. We find that the generated parallel electric field is localised in the density inhomogeneity region and rotates in the same direction and with the same angular frequency as the initially launched IAW. Our numerical simulations seem also to suggest that the "knee" often found in the solar flare electron spectra can alternatively be interpreted as the Landau damping (Cerenkov resonance effect) of IAWs due to the wave-particle interactions.Comment: Physics of Plasmas, in-press, September 2012 issue, final accepted versio

Design study for a magnetically supported reaction wheel

Results are described of a study program in which the characteristics of a magnetically supported reaction wheel are defined. Tradeoff analyses are presented for the principal components, which are then combined in several reaction wheel design concepts. A preliminary layout of the preferred configuration is presented along with calculated design and performance parameters. Recommendations are made for a prototype development program

Modelling the measured local time evolution of strongly nonlinear heat pulses in the Large Helical Device

In some magnetically confined plasmas, an applied pulse of rapid edge cooling can trigger either a positive or negative excursion in the core electron temperature from its steady state value. We present a new model which captures the time evolution of the transient, non-diffusive local dynamics in the core plasma. We show quantitative agreement between this model and recent spatially localized measurements (Inagaki et al 2010 Plasma Phys. Control. Fusion 52 075002) of the local time-evolving temperature pulse in cold pulse propagation experiments in the Large Helical Device

Particle acceleration by circularly and elliptically polarised dispersive Alfven waves in a transversely inhomogeneous plasma in the inertial and kinetic regimes

Dispersive Alfven waves (DAWs) offer, an alternative to magnetic reconnection, opportunity to accelerate solar flare particles. We study the effect of DAW polarisation, L-, R-, circular and elliptical, in different regimes inertial and kinetic on the efficiency of particle acceleration. We use 2.5D PIC simulations to study how particles are accelerated when DAW, triggered by a solar flare, propagates in transversely inhomogeneous plasma that mimics solar coronal loop. (i) In inertial regime, fraction of accelerated electrons (along the magnetic field), in density gradient regions is ~20% by the time when DAW develops 3 wavelengths and is increasing to ~30% by the time DAW develops 13 wavelengths. In all considered cases ions are heated in transverse to the magnetic field direction and fraction of the heated particles is ~35%. (ii) The case of R-circular, L- and R- elliptical polarisation DAWs, with the electric field in the non-ignorable transverse direction exceeding several times that of in the ignorable direction, produce more pronounced parallel electron beams and transverse ion beams in the ignorable direction. In the inertial regime such polarisations yield the fraction of accelerated electrons ~20%. In the kinetic regime this increases to ~35%. (iii) The parallel electric field that is generated in the density inhomogeneity regions is independent of m_i/m_e and exceeds the Dreicer value by 8 orders of magnitude. (iv) Electron beam velocity has the phase velocity of the DAW. Thus electron acceleration is via Landau damping of DAWs. For the Alfven speeds of 0.3c the considered mechanism can accelerate electrons to energies circa 20 keV. (v) The increase of mass ratio from m_i/m_e=16 to 73.44 increases the fraction of accelerated electrons from 20% to 30-35% (depending on DAW polarisation). For the mass ratio m_i/m_e=1836 the fraction of accelerated electrons would be >35%.Comment: Final accepted version. To appear in Physics of Plasmas, volume 18, issue 9 (September 2011