Effects of Resonant Helical Field (RHF) on Equilibrium Properties of IR-T1 Tokamak Plasma

In this paper we present an experimental study of effects of Resonant Helical Field (RHF) on Shafranov parameter and Shafranov shift in IR-T1 tokamak. For this purpose a four magnetic pickup coils were designed, constructed, and installed on outer surface of the IR-T1 tokamak chamber, and then the Shafranov parameter and Shafranov shift obtained. On the other hand, the external RHF applied on tokamak plasma and its effects on results measured. Experimental results of measurements with and without RHF (L = 2, L = 3, L = 2 & 3) show that the addition of a relatively small amount of RHF especially L = 3 mode could be effective for improving the quality of tokamak plasma discharge by flatting the plasma current and reducing the Shafranov parameter and Shafranov shift.     

A novel technique for the measurement of plasma displacement in IR-T1 tokamak

In this paper we present a novel technique based on poloidal magnetic flux for determination of plasma displacement in IR-T1 tokamak. This instrument consists of a two semicircle wires which installed toroidally on inner and outer sides of tokamak chamber and connected with each other. In order to receive the poloidal flux on Last Closed Flux Surface (LCFS); this instrument installed on polar coordinate so as projection of it on midplane lie on LCFS. Really, this instrument receives the difference between poloidal flux on inner and outer sides of LCFS, which we needed in calculating of the Shafranov shift. Main benefits of our proposed instrument are that it is a simple, solid, and also its output is directly related to the Shafranov shift. Based on this technique we determined the plasma position and to compare the result obtained using this method, multipole moments method is also experimented on IR-T1. Results of the two techniques are in good agreement with each other.     

Bacteremia caused by CDC group IV c-2 in a patient with acute leukemia

Human infection due to CDC group IV c-2, a gram negative bacillous, are rare. We describe a case of nosocomial bacteremia caused by this organism in a neutropenic patient with acute lymphoblastic leukemia and include a literature review of CDC group IV c-2 infection in patients with hematologic malignancies.     

Comparison of methods for estimating loss from water storage by evaporation and impacts on reservoir management

Reservoirs are the key infrastructure of water resources management. A controlling variable of reservoir operation is evaporation, which in semi‐arid and arid regions may consume a large fraction of reservoir storage annually. This paper assesses the role of evaporation and the choice of evaporation methods on reservoir operation. The operation of the reservoir is calculated with the standard operation policy (SOP). Several efficiency criteria are employed to rank the evaporation‐calculation methods with the technique for the order of preference by similarity to ideal solution (TOPSIS). The method presented in this paper is illustrated by applying its application to Karkheh reservoir, the largest in Iran.     

Vibration Energy Harvesting Using Piezoelectric Elements by Multi-switch Circuit with Adaptive Inductance

International Journal of Control, Automation and Systems - Mechanical vibration energy harvesting using multi-switch circuit with adaptive inductance is a new method based on impedance matching...     

Plasma Stability Evaluation Based on MHD Activity and Hard X-Ray Emission in the IR-T1 Tokamak

Determinations of the poloidal beta, internal inductance, plasma energy, plasma pressure, plasma temperature, plasma resistance, plasma effective atomic number, magneto-hydrodynamics (MHD) activity, Runaway electrons energy and energy confinement time are essential for tokamak experiments and optimized operation. Also some of the plasma information can be deduced from these parameters, such as plasma toroidal current profile, and MHD instabilities. In this contribution we investigated about measurements of some plasma parameters as well as MHD activity and Runaway electrons energy. For this purpose we used the magnetic diagnostics and a hard X-ray spectroscopy in IR-T1 tokamak. A hard X-ray emission is produced by collision of the Runaway electrons with the plasma particles or limiters. The mean energy was calculated from the slope of the energy spectrum of hard X-ray photons. In this paper in order to measure energy of the Runaway electrons, we obtained hard X-ray energy in every 5 ms intervals, from the beginning to the end of plasma. Results indicated mean energy of Runaway electrons is maximum during the 0–5 ms interval.     

Multipole Moments Based Study on Determination of Toroidal Plasma Equilibrium Position and Shift

The multipole moments based technique studied for the determination of toroidal plasma column shift. First, we presented analytical details for using this technique. Then, principle of two different models based on this technique for design and fabrication of a modified Rogowski coil (MRC) and Saddle Sine coil (SSC) will be presented. Because of continuous measurements of magnetic field distribution around the toroidal plasma using the MRC and SSC, this technique is the good method for the determination of toroidal plasma column shift.     

Evolution of the IR-T1 Tokamak Plasma Local and Global Parameters

In this contribution, an attempt is made to investigate of evolution of some local and global plasma parameters in IR-T1 tokamak. For this purpose, four magnetic pickup coils were designed, constructed and installed on outer surface of the tokamak and then asymmetry factor is obtained from them. On the other hand, diamagnetic loop were designed and installed on IR-T1 and poloidal beta is determined from it. Therefore, the internal inductance and effective edge safety factor measured. Also, time evolution of the energy confinement time is measured using the diamagnetic loop. Experimental results show that maximum energy confinement time (which correspond to minimum collisions, minimum microinstabilities and minimum transport), relate to the low values of effective edge safety factor and also relate to the low values of internal inductance.