0.5V 3rd-order Tunable gm-C Filter

This paper proposes a 3rd-order gm-C filter that operates with the extremely low voltage supply of 0.5V. The employed transconductor is capable for operating in an extremely low voltage power supply environment. A benefit offered by the employed transconductor is that the filter’s cut-off frequency can be tuned, through a dc control current, for relatively large ranges. The filter structure was designed using normal threshold transistors of a triple-well 0.13μm CMOS process and is operated under a 0.5V supply voltage; its behavior has been evaluated through simulation results by utilizing the Analog Design Environment of the Cadence software

Finite element elastic-plastic-creep and cyclic life analysis of a cowl lip

Results are presented of elastic, elastic-plastic, and elastic-plastic-creep analyses of a test-rig component of an actively cooled cowl lip. A cowl lip is part of the leading edge of an engine inlet of proposed hypersonic aircraft and is subject to severe thermal loadings and gradients during flight. Values of stresses calculated by elastic analysis are well above the yield strength of the cowl lip material. Such values are highly unrealistic, and thus elastic stress analyses are inappropriate. The inelastic (elastic-plastic and elastic-plastic-creep) analyses produce more reasonable and acceptable stress and strain distributions in the component. Finally, using the results from these analyses, predictions are made for the cyclic crack initiation life of a cowl lip. A comparison of predicted cyclic lives shows the cyclic life prediction from the elastic-plastic-creep analysis to be the lowest and, hence, most realistic

Structural response of SSME turbine blade airfoils

Reusable space propulsion hot gas-path components are required to operate under severe thermal and mechanical loading conditions. These operating conditions produce elevated temperature and thermal transients which results in significant thermally induced inelastic strains, particularly, in the turbopump turbine blades. An inelastic analysis for this component may therefore be necessary. Anisotropic alloys such as MAR M-247 or PWA-1480 are being considered to meet the safety and durability requirements of this component. An anisotropic inelastic structural analysis for an SSME fuel turbopump turbine blade was performed. The thermal loads used resulted from a transient heat transfer analysis of a turbine blade. A comparison of preliminary results from the elastic and inelastic analyses is presented

Mean field analysis of quantum phase transitions in a periodic optical superlattice

In this paper we analyze the various phases exhibited by a system of ultracold bosons in a periodic optical superlattice using the mean field decoupling approximation. We investigate for a wide range of commensurate and incommensurate densities. We find the gapless superfluid phase, the gapped Mott insulator phase, and gapped insulator phases with distinct density wave orders.Comment: 6 pages, 7 figures, 4 table

Life and (non)Living: Technological and Human Conglomeration in Android Kunjappan Version 5.25

In post-modern society, we (humans) share our space with machines. Though there is no doubt in the efficiency of the machines there is always a doubt in their reason. Machines being programmed cannot exercise reason like humans. Their assistance is limited to the commands designed by the engineer. The Malayalam movie Android Kunjappan Version 5.25 pictures the limitations and advantages of one such robotic creation. The movie narrates the tale of an old man and his association with a robot which becomes his solace and companion. The film questions the association between humans and machines. It raises the fear of constructing and destroying the boundaries between the machine world and the human world. This article attempts to use the concept of cyborg introduced by Donna Haraway in ‘Cyborg Manifesto’; though Haraway uses the concept of a cyborg from a Feminist perspective, the paper attempts to look at the relationship between man and machine using the concept ‘cyborg’. This fusion of the living and non-living is sceptical and this anxiety is presented in the film. The film also captured the naivety of the commoners who are new to the monstrous world of machines. The paper’s primary aim is to list how cyborgs transgress the limitations set by society. Another objective is to discuss the anxieties of the post-modern world when technology and life hold hands. The article considers the film a futuristic art that leaves a message to the viewers; cyborgs will become an inevitable facet of the human world

Meckel's diverticulitis due to actinomycosis

The patient was 36 years old female admitted due to periumbilical pain and anorexia since about 24 h prior to hospitalization. She underwent laparotomy with impression of acute appendicitis. Operative finding was Meckel's diverticulitis, so appendectomy and resection of diverticular bearing Ileum with end to end anastomosis was performed. Post operation course was uneventful and she discharged 5 days later. Pathological study confirmed the diagnosis of Meckel's diverticulitis due to actinomycosis as the cause of diverticular obstruction. The relatively rare incidence and preoperative diagnosis difficulties make publication of this case worthwhile