One of the main challenges in the development of a plasma diagnostic and control system for DEMO is the need to cope with unprecedented radiation levels in a tokamak during long operation periods. A list of diagnostics required for plasma control has been developed during the pre-conceptual design phase. Different approaches are proposed for the integration of these diagnostics in DEMO: in equatorial and upper ports, in the divertor cassette, on the inner and outer surfaces of the vacuum vessel and in diagnostic slim cassettes, a modular approach developed for diagnostics requiring access to the plasma from several poloidal positions.
View Article and Find Full Text PDFWe investigate the influence of air holes on phase sensitivity in microstructured optical fibers to longitudinal strain. According to the numerical simulations performed, large air holes in close proximity to a fiber core introduce significant compression stress to the core, which results in an increase in the effective refractive index sensitivity to longitudinal strain. The theoretical investigation is verified by an experiment performed on four fibers drawn from the same preform and differentiated by air hole diameter.
View Article and Find Full Text PDFThe dense plasma focus (DPF) device-DPF-1000U which is operated at the Institute of Plasma Physics and Laser Microfusion is the largest that type plasma experiment in the world. The plasma that is formed in large plasma experiments is characterized by vast numbers of parameters. All of them need to be monitored.
View Article and Find Full Text PDFThe spectra of neutrons outside the plasma focus device PF-1000 with an upper energy limit of ≈1 MJ was measured using a Bonner spheres spectrometer in which the active detector of thermal neutrons was replaced by nine thermoluminescent chips. As an a priori spectrum for the unfolding procedure, the spectrum calculated by means of the Monte Carlo method with a simplified model of the discharge chamber was selected. Differences between unfolded and calculated spectra are discussed with respect to properties of the discharge vessel and the laboratory layout.
View Article and Find Full Text PDFTwo hundred and forty-one patients were treated with radical hysterectomy at our institution between 1949 and December, 1978. The corrected 5-year survival rate for all patients with squamous cell carcinoma of the cervix was 73%. Seventeen percent of patients with occult invasive carcinoma had positive lymph nodes at the time of operation.
View Article and Find Full Text PDF