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The introduction of microprocessor technology enabled multiple protection functions to be integrated into a common protection platform which has advantages when applied to generator protection. This paper provides an insight into industry application experience in using multifunction generator protection systems on various sizes and types of generators. Included are discussions on application and performance differences between multifunction protection systems and single function static and electromechanical relaying devices. Also included is a summary of the various types of tests performed on the multifunction protection systems by the user. The paper additionally addresses the need for application of redundancy and backup protection when applying multifunction generator protection systems on large or important generators. Keywords: Multifunctional Protection System, Generator Protective Relay, Redundant, Tripping, Signal Processing

Upgrading of power plant systems and equipment is becoming a major theme for many utilities. Due to operational cost pressures, competitiveness, life extension, and the desire for better productivity, condition assessment programs are being implemented. One aspect of this is the enhancement/upgrade of existing generator protection schemes with digital systems. Traditionally this protection has been provided by a complement of discrete component relays. These relays have included both electromechanical and static types. Considering a digital enhancement/upgrade offers the owner of installed generation equipment several unique advantages. These include more complete machine protection, diagnostics capabilities for greater productivity and maintenance optimization, life extension with minimal implementation, and the operational advantages of sequence of events, present values and communications capabilities.

The Main Central Thrust Zone (MCTZ) in the Alaknanda valley, NW Himalaya, affected the Lesser Himalayan Crystalline Sequence and has a gradual transition to the structurally overlying Higher Himalayan Crystalline Sequence (HHCS). This boundary is defined on the basis of the following petrographic features in pelitic rocks at the base of the HHCS: (i) first appearance of microscopic needles of kyanite upon moving up-section along the transect; (ii) garnet porphyroblasts with random inclusion pattern and non-rotational growth history, which contrast with the garnet porphyroblasts in MCTZ rocks with spiral inclusion trails; and (iii) chemically homogeneous garnet porphyroblasts as opposed to the growth-zoned garnets in MCTZ rocks. Pseudosection modelling and garnet isopleth thermobarometry of pelitic rocks yield peak metamorphic conditions of 6.3-7.5 kbar and 550-582°C in the MCTZ, and 8.0-10.0 kbar and 610-650°C in the basal part of the HHCS. The results indicate continuity in the P-T field gradient across the contact between the MCTZ and HHCS. The MCTZ shows an inverted metamorphic sequence from biotite to garnet zones. Metamorphism in the basal part of the HHCS is in the kyanite zone, which is continuous with the inverted metamorphic sequence. Both P and T increase up-section, peak in the lower HHCS and then decrease higher up in the HHCS unit. The observations are consistent with predictions of a recently proposed thermomechanical model in which temperature in the shear zone rises due to viscous heating and pressure rises as a result of weakening of the rocks. Keywords Inverted metamorphism * Pseudosection * Main central thrust zone * Garhwal Himalaya, Introduction The Main Central Thrust Zone (MCTZ) has long been recognised as one of the major terrane boundary shear zones of the Himalayan orogen that accommodated a significant amount of [...]

Twenty-five hypertensive patients were treated in an open trial with indoramin and hydrochlorothiazide for periods up to 43 months (mean 13 months). The average standing blood pressure decreased from 180/115 mm Hg to 148/94 mm Hg. Sixteen (64%) patients maintained satisfactory response with a mean daily dose of 101.5 mg of indoramin., Postural hypotension, reflex tachycardia or weight gain were not found in any patient. Eight patients (32%) taking high doses experienced troublesome giddiness, drowsiness and depression necessitating withdrawal of the drug. No electrocardiographic or biochemical adverse effects were noted., Normotension was prolonged in three patients when the drug was abruptly withdrawn. [ABSTRACT FROM AUTHOR]

Examines the cellular location of Niemann-Pick C2 (NPC2) protein in cultured human fibroblasts and Chinese hamster ovary cells. Presence of NPC2 in the lysosomes of both cholesterol-depleted and -replenished cells; Occurrence of a partial overlap in the trafficking and organellar sites of accumulation of NPC2 and Niemann-Pick C1 proteins.