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This paper briefly outlines the current status of CODAC system of the EAST tokamak. Integrated central system has been working for synchronizing all the subsystems and responsible for the integral safety protection by interlock. Data acquisition system has been established for the discharge with duration up to 100 seconds. Various data visualization tools such as EASTVIEWER to view the flux surfaces, RTSCOPE to view plasma boundary and CCD image in real-time, WEBSCOPE to view the diagnostic data via a web browser and EASTVOD to view and search plasma discharge image at different time, haven developed for EAST operation. Plasma control system is inherited from DIII-D, and has been matured to a stage to feedback control the EAST plasma shape, density and current in real time. [ABSTRACT FROM AUTHOR]

Experiments for the laser guiding studies has been carried out with the 30-fs 100-TW Ti:sapphire laser pulse interaction with the underdense plasma produced by a long-slab (1.2 × 10 mm²) gas jet and an ablative laser-triggered discharged capillary. Formation of an extremely long plasma channel with a length (~10 mm) 10 times above the Rayleigh length is observed when the laser pulse power is much higher than the critical power for relativistic self-focusing. The long-self-guiding-channel formation is accompanied by the electron acceleration with a low transverse emittance (< 0.8π mm mrad) and high electric current (~10 nC/shot), as well as the generation of a quasi-monoenergetic electron bunch with an energy of ~80 MeV. In order to continuously elongate the plasma channel, a 4-cm-scale discharged capillary was used. We successfully demonstrated laser-plasma acceleration of high-quality electron beams up to nearly semigigaelectronvolts. Our results exactly verified the prediction of laser wakefield acceleration through a centimeter-scale plasma channel in the "blowout bubble" regime, where a microscale plasma cavity produced through the ultrarelativistic laser-plasma interactions plays an essential role in the self-injection and acceleration of electrons. [ABSTRACT FROM AUTHOR]

Copper metallized AlGaAs/InGaAs pseudomorphic high-electron-mobility transistor (PHEMT) single-pole-double-throw (SPDT) switches utilizing platinum (Pt, 70nm) as the diffusion barrier is reported for the first time. In comparison with the Au metallized switches, the Cu metallized SPDT switches exhibited comparable performance with insertion loss of less than 0.5dB, isolation larger than 35dB and the input power for one dB compression (input P1dB ) of 27dBm at 2.5GHz. These switches were annealed at 250deg for 20h for thermal stability test and showed no degradation of the dc characteristics after the annealing. Also, after 144h of high temperature storage life (HTSL) environment test, these switches still remained excellent and reliable radio frequency (RF) characteristics. It is successfully demonstrated for the first time that the copper metallization using Pt as the diffusion barrier could be applied to the GaAs monolithic microwave integrated circuits switch fabrication with good RF performance and reliability [ABSTRACT FROM PUBLISHER]

In this paper, an efficient fuzzy second correction scheme (FSCS) to improve the complementarity condition in a predictor-corrector interior point algorithm (PCIPA) for optimal power flows (OPF) is proposed. At every iteration, the proposed FSCS estimates, with the help of fuzzy logic, a better barrier parameter for each complementarity pair and effectively computes a second corrector term to improve the convergence of the PCIPA. The effectiveness of FSCS is demonstrated by several large-scale test cases. From the numerical results, it is found that the proposed FSCS improves PCIPA by 20% in terms of CPU times. [ABSTRACT FROM PUBLISHER]