Coronal loop hydrodynamics. The solar flare observedon November 12 1980 revisited: the UV line emission

We revisit a well-studied solar flare whose X-ray emission originating from a simple loop structure was observed by most of the instruments on board SMM on November 12 1980. The X-ray emission of this flare, as observed with the XRP, was successfully modeled previously. Here we include a detailed modeling of the transition region and we compare the hydrodynamic results with the UVSP observations in two EUV lines, measured in areas smaller than the XRP rasters, covering only some portions of the flaring loop (the top and the foot-points). The single loop hydrodynamic model, which fits well the evolution of coronal lines (those observed with the XRP and the \FeXXI 1354.1 \AA line observed with the UVSP) fails to model the flux level and evolution of the \OV 1371.3 \AA line.Comment: A&A, in press, 6 pages, 5 figure

A phenomenological model for predicting the early development of the flame kernel in spark-ignition engines

This work presents a simple and effective phenomenological model for the prediction of the early growth of the flame kernel in SI engines, including its initiation as a result of the electrical breakdown of the fuel/air mixture between the spark plug electrodes. The present model aims to provide an improved description of the ignition-affected early phases of flame kernel development compared to the majority of models currently available in literature. In particular, these models focus on electrical energy supply and turbulence, whereas the stretch-induced kernel growth slowdown is quantified with linear models that are inconsistent with the small kernel radius. For the flame kernel initiation, this model replaces the current methods that rely on 1D heat diffusion within a plasma column with a more consistent analysis of post-breakdown conditions. Concerning the kernel growth, the present model couples the mass and energy conservation equations of a spherical kernel with the species and temperature profiles outside of it. This combination leads to a non-linear description of the flame stretch, according to which the kernel development is controlled by the Lewis-number-dependent balance between the heat gained via combustion and the heat lost via thermal diffusion. As a result, the kernel temperature differs from the adiabatic flame temperature, causing the laminar flame speed to change from its adiabatic value and ultimately affecting the overall kernel development. Kernel growth predictions are conducted for laminar flames and compared to literature data, showing a satisfactory agreement and highlighting the ability to describe the stretch-induced kernel slowdown, up to its possible extinction. A good agreement with literature data is also obtained for kernel expansions under moderately turbulent conditions, typical of internal combustion engines. The simple formulation of the present model enables swift integration into phenomenological combustion models for spark-ignition engines, while simultaneously offering useful insight into the early kernel development even for CFD-based approaches

Unified processing of constraints for interactive simulation

International audienceThis paper introduces a generic way of dealing with a set of different constraints (bilateral, unilateral, dry friction) in the context of interactive simulation. We show that all the mentioned constraints can be handled within a unified framework: we define the notion of generalized constraints, which can be derived into most classical constraints types. The solving method is based on an implicit treatment of constraints that provides good stability for interactive applications using deformable models and rigid bodies. Each constraint law is expressed in constraint subspace, making constraint evaluation much easier. A global solution is calculated using an iterative process that takes into account the mechanical coupling between the constraints. Various examples, from basic to more complex, show the practical advantage of using generalized constraints, as a way of creating heterogeneously constrained systems, as well as the scalability of the proposed method

The three-body recombination of a condensed Bose gas near a Feshbach resonance

In this paper, we study the three-body recombination rate of a homogeneous dilute Bose gas with a Feshbach resonance at zero temperature. The ground state and excitations of this system are obtained. The three-body recombination in the ground state is due to the break-up of an atom pair in the quantum depletion and the formation of a molecule by an atom from the broken pair and an atom from the condensate. The rate of this process is in good agreement with the experiment on $^{23}$Na in a wide range of magnetic fields.Comment: 10 pages, 2 figures, to be published in Phys. Rev.

Aplicação foliar de fertilizante organo mineral e soluções de ácido húmico em soja sob plantio direto.

O objetivo deste trabalho foi avaliar o efeito da aplicação foliar de produto à base de ácido húmico e da fração isolada sobre a produtividade de soja (Glycine max) em sistema de plantio direto no Cerrado.bitstream/CNPS-2010/14934/1/circtec35-2006-fertilizante.pd

P2A0 Post Seksio Sesarea Transperitoneal Profunda Dengan Sindrom Sheehan Et Causa Perdarahan Pasca Persalinan Dini Et Causa Atonia Uteri

Sindrom Sheehan (SS) adalah hypopituitarism pasca persalinan akibat nekrosis iskemik yang menghasilkan hipotensi akibat perdarahan masif saat atau sesudah persalinan. Riwayat perdarahan pasca persalinan (PPP), gagal menyusui, dan amenore sekunder penting sebagai penunjuk diagnosis. Sindrom Sheehan sering berkembang dan terdiagnosis lambat. Diagnosis dini dan pengobatan yang sesuai sangatlah penting untuk menurunkan morbiditas dan mortalitas pasien. Laporan kasus ini menjelaskan seorang wanita usia 28 tahun, dengan PPP 5 jam post seksio sesarea transperitoneal profunda (SSTP) di luar atas indikasi (ai) gawat janin. Pemeriksaan fisik didapatkan keadaan umum buruk, kesadaran somnolen, tekanan darah 100/70 mmHg, nadi 120 kali/menit, pernapasan 24 kali/menit, suhu 36,8 0C, dan konjungtiva palpebra anemis. Pemeriksaan obstetrik didapatkan tinggi fundus uteri (TFU) tidak teraba, tidak ada kontraksi, dan tidak ada perdarahan aktif. Hasil laboratorium menunjukkan Hemoglobin 3,5 g/dL. Dilakukan observasi tanda-tanda vital, pemberian O2 10 L sungkup, intravena fluid drip (IVFD) dua jalur berupa guyur ringer laktat (RL) dan RL + oksitosin 20 IU 10 tetes/menit, pemasangan kateter urin menetap dengan evaluasi input dan output cairan, dan laparatomi cito berupa histerektomi subtotal. Pasca operasi pasien dirawat di Intensive Care Unit (ICU) 19 hari lalu dilanjutkan perawatan di bangsal selama 3 hari. Hingga akhir perawatan pasien komposmentis, air susu ibu (ASI) tidak keluar, dan tidak ditemukan adanya perdarahan pervaginam

TCAD Analysis of Leakage Current and Breakdown Voltage in Small Pitch 3D Pixel Sensors

Small-pitch 3D pixel sensors have been developed to equip the innermost layers of the ATLAS and CMS tracker upgrades at the High Luminosity LHC. They feature 50 × 50 and 25 × 100 μm2 geometries and are fabricated on p-type Si-Si Direct Wafer Bonded substrates of 150 μm active thickness with a single-sided process. Due to the short inter-electrode distance, charge trapping effects are strongly mitigated, making these sensors extremely radiation hard. Results from beam test measurements of 3D pixel modules irradiated at large fluences (1016neq/cm2) indeed demonstrated high efficiency at maximum bias voltages of the order of 150 V. However, the downscaled sensor structure also lends itself to high electric fields as the bias voltage is increased, meaning that premature electrical breakdown due to impact ionization is a concern. In this study, TCAD simulations incorporating advanced surface and bulk damage models are used to investigate the leakage current and breakdown behavior of these sensors. Simulations are compared with measured characteristics of 3D diodes irradiated with neutrons at fluences up to 1.5 × 1016neq/cm2. The dependence of the breakdown voltage on geometrical parameters (e.g., the n+ column radius and the gap between the n+ column tip and the highly doped p++ handle wafer) is also discussed for optimization purposes