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The KSTAR (Korea Superconducting Tokamak Advanced Research) superconducting magnet system adopts a superconducting CICC(Cable-In-Conduit Conductor) type conductor. It consists of 16 TF (Toroidal Field) coils and 14 PF (Poroidal Field) coils and it also uses two different types of CICCs-Nb3Sn cable with Incoloy 908 conduit and NbTi cable with 316LN stainless-steel conduit. A special CICC jacketing system is developed for the KSTAR CICC fabrication: the tube-mill process, which consists of forming, welding, sizing and squaring procedure. The cabling process for TF and PF superconducting cable and the fabrication process of each CICCs (TF CICC and PF CICC) is described. The welding of conduit materials are also discussed. The fabrication results such as the geometrical specification, micro structure and the void fraction will be discussed more...

The KSTAR (Korea Superconducting Tokamak Advanced Research) superconducting magnet system which consists of 16 TF coils and 14 PF coils adopts a superconducting CICC (Cable-In-Conduit Conductor) type conductor. The KSTAR magnet system uses two different types of CICCs-Nb/sub 3/Sn cable with Incoloy 908 conduit and NbTi cable with 316LN stainless-steel conduit. A continuous CICC jacketing system is developed for the KSTAR CICC fabrication and the jacketing system uses the tube-mill process. It consists of forming, welding, sizing and squaring procedures. The welding condition of CICCs and the fabrication process is described. The repair of the CICC is also discussed. more...

In this paper, we present the simple approach in study the impact of channel doping on the operation of the junctionless transistor transistor in 25 nm gate lengths through 2D-TCAD Sentaurus simulation tools. We increase the channel doping up to the level of doping source and drain, thus creating the junctionless phenomena between source and drain. The transistor parameters such as threshold voltage, transconductance, subthreshold slope, drain-induced barrier lowering are extracted. The impacts of low and high drain voltages are also considered. The higher the doping concentration the larger drain current can be produced, however the drawback is larger subthreshold slope is also obtained due to wider channel preventing fully-depletion. more...

A number of Debye-type dielectric relaxation peaks have been observed for acceptor-doped KTaO3 and CaTiO3, both of which have the perovskite structure. In the case of KTaO3, the dopants are divalent and trivalent cations of the iron group, while CaTuO3 is doped with Al3+. These peaks occur at relatively low temperatures and have activation energies in the range 0.1–0.4 eV, much lower than the activation energy for the conductivity. They are attributed to M-Vo pairs, where M represents the dopant ion and Vo the oxygen ion vacancy. The possibility that the peaks are due to partial reorientation of the pairs in “off-center” configurations is ruled out by electron paramagnetic resonance work on Mn-doped KTaO3 by Geifman and coworkers (I.P. Bykov, I.N. Geifman, M.D. Glinchuk and B.K. Krulikovskii, Sov. Phys. Solid State, 22 (1980) 1248). They must therefore be due to full reorientation, and possible reasons for the low activation energy are discussed. A study of the peak heights shows that a large correction for internal field effects is necessary for KTaO3, but this correction is not nearly so large as that given by the Lorentz factor. more...

A new self-driven active clamp forward converter, in which the extra driving circuit for the active clamp switch is not required, is proposed. In the proposed converter, the auxiliary winding is used instead of the extra driving circuit to drive the active clamp switch so that the converter has a simple structure comparing to the conventional one. The operation principles of the proposed converter, in which synchronous rectification is employed, are presented. Experimental results for the prototype converter of 100 W(5 V/20 A) are also presented to verify its validity. more...

Using specimens from various organs originally processed for routine histopathological study (wax embedding), a total of 2044 autopsy cases were reviewed to identify those with primary amyloidosis of the heart. A total of 7 such cases, involving the heart only, was identified with the aid of appropriate stains and polarized light. The heart tissue was subsequently re-processed for study by electron microscopy. In all 7 cases, large deposits of amyloid fibrils were found around the blood capillaries and smaller amounts between individual myocardial fibres. The possible origin of the amyloid fibrils is briefly discussed within the limitations imposed by the source of the material; it is suggested that they may be formed either by the muscle cells or from material reaching the tissue via the capillaries or alternatively, as the result of an interaction between the cells and circulating immunoglobulins. more...

A method is proposed for the indirect determination of trace amounts of cyanide. After release and distillation of the cyanide, which is collected in 1·0 M sodium hydroxide, the cyanide is reacted with a known and excess amount of copper(II) ions. The excess of the Cu(II) ions is determined by polarography, and from the amount of Cu(II) which has reacted, the amount of cyanide originally present is calculated. more...