Mixed Non-Uniform Width / Evanescent Mode Ceramic Resonator Waveguide Filter With Wide Spurious Free Bandwidth

This paper presents a method to improve the spurious performance of integrated ceramic waveguide filters. Nonuniform width ceramic waveguide resonator and evanescent mode ceramic resonators are employed together to the resonant frequencies of higher order modes. The proposed designs give 75% improvement in stop band response when compared to uniform width ceramic waveguide filter. Simulated results of two six pole chebyshev filters are presented here with improved stop band performance

Novel RF Interference Rejection Technique using a Four-port Diplexer

A novel RF interference rejection technique using four-port network is presented in this paper by using two diplexers combined together. This technique offers the signal isolation of 68.46 dB between transmitter and receiver module, which is the best figure ever reported. The four-port network exploits both high and low-Q factor filters for the cost reduction. The design tolerance with phase deviation between 180º and 183º of four-port network was investigated and the novel concept still has signal isolation (S32) of better than 65.47 dB, which is still superior compared to the existing diplexer. Finally, RF interference rejection technique can be used in wireless communication systems whereas small size, low losses and low complexity are required

Nano and micro Hall-effect sensors for room-temperature scanning hall probe microscopy

Cataloged from PDF version of article.GaAs/AlGaAs two-dimensional electron gas (GaAs-2DEG) Hall probes are impractical for sub-micron room-temperature scanning Hall microscopy (RT-SHPM), due to surface depletion effects that limit the Hall driving current and magnetic sensitivity (B in). Nano and micro Hall-effect sensors were fabricated using Bi and InSb thin films and shown to be practical alternatives to GaAs-2DEG probes for high resolution RT-SHPM. The GaAs-2DEG and InSb probes were fabricated using photolithography and the Bi probes by optical and focused ion beam lithography. Surface depletion effects limited the minimum feature size of GaAs-2DEG probes to similar to1.5 mum(2) with a maximum drive current I-max of similar to3 muA and B-min similar to 0.2 G/rootHz. The B-min of 1.5 mum(2) InSb Hall probes was 6 x 10(-1) G/rootHz at I-max of 100 muA. Further, 200 nm x 200 nm Bi probes yielded good RT-SHPM images of garnet films, with I-max and sensitivity of 40 muA and similar to0.80 G/rootHz, respectively. (C) 2004 Elsevier B.V. All rights reserved

Social status modulates prosocial behavior and egalitarianism in preschool children and adults

Humans are a cooperative species, capable of altruism and the creation of shared norms that ensure fairness in society. However, individuals with different educational, cultural, economic, or ethnic backgrounds differ in their levels of social investment and endorsement of egalitarian values. We present four experiments showing that subtle cues to social status (i.e., prestige and reputation in the eyes of others) modulate prosocial orientation. The experiments found that individuals who experienced low status showed more communal and prosocial behavior, and endorsed more egalitarian life goals and values compared with those who experienced high status. Behavioral differences across high- and low-status positions appeared early in human ontogeny (4-5 y of age)

Four-port Microstrip Diplexer For RF Interference Rejection

A novel four-port microstrip diplexer for RF interference rejection is presented in this paper by combining two diplexers together. This technique offers the signal isolation of 62.9 dB between transmitter and receiver module, which is the best figure ever reported. The four-port network exploits microstrip structure for the cost reduction, while still offering superior figure-of-merit compared to the existing state-of-the-art diplexers. Finally, four-port microstrip diplexer for RF interference rejection can be used in IMT-2000 applications whereas device miniaturization and low infrastructure cost are required

High sensitivity and multifunctional micro-Hall sensors fabricated using InAlSb/InAsSb/InAlSb heterostructures

Further diversification of Hall sensor technology requires development of materials with high electron mobility and an ultrathin conducting layer very close to the material's surface. Here, we describe the magnetoresistive properties of micro-Hall devices fabricated using InAlSb/InAsSb/InAlSb heterostructures where electrical conduction was confined to a 30 nm-InAsSb two-dimensional electron gas layer. The 300 K electron mobility and sheet carrier concentration were 36 500 cm(2) V-1 s(-1) and 2.5 x 10(11) cm(-2), respectively. The maximum current-related sensitivity was 2 750 V A(-1) T-1, which was about an order of magnitude greater than AlGaAs/InGaAs pseudomorphic heterostructures devices. Photolithography was used to fabricate 1 mu m x 1 mu m Hall probes, which were installed into a scanning Hall probe microscope and used to image the surface of a hard disk

Clinical Thermoradiotherapy

A clinical trial is currently in progress to determine the efficacy of combined fractions of hyperthermia and radiation. The protocol consists of two parts. First, four fractions of microwave-induced hyperthermia (45.0° ± 0.5°C) are applied for 1 1/2 hours to the volume encompassing the tumor, each separated by 72 hours. After a one-week rest, a second series of four fractions is administered again at 72- hour intervals. Each fraction consists of a 400 rad dose of radiation followed within 20 minutes by hyperthermia (42.5 ± 0.5°C) for 1 1/2 hours. Currently, we have treated 62 patients with 82 fields with a mean follow-up time of six months to date. Total regression was observed in 60% of all cases, and partial regression in 33%; no response was seen in only 6% of all those treated. Five local and three marginal recurrences have been observed. This paper discusses details of response based on site, histology, and classification