RF multicoupler design techniques to minimize problems of corona, multipaction, and stability

A mathematical expression was derived describing multipacting and corona effects in a coaxial cavity. Both mechanical and electrical design techniques were investigated to minimize the susceptibility of coaxial cavity to corona and multipacting-type breakdown. To assist in the design of a multicoupler free from corona and multipactor breakdown, a flow chart obtained from the derived mathematical expression is included

Gastrointestinal stromal tumour as a rare association with neurofibromatosis type 1

Gastrointestinal stromal tumours (GIST) are rare tumours of mesenchymal origin. These can be associated with neurofibromatosis type 1 (NF1), which is an autosomal dominant disorder. The prevalence of GIST in NF1 is estimated at 3.9-25%. This paper describes the presentation of a GIST arising from the jejenum in a 75-year-old lady with NF1, who presented with gastrointestinal bleeding. This was diagnosed by CT angiography. She was managed with laparotomy, with resection of small bowel, and an ischaemic segment of large bowel with two primary anastomoses. Pathology showed GIST of spindle cell type (Figs 3 and 4), 90 mm in size, with complete local excision. The patient was discharged on the eighth post-operative day and is currently undergoing regular clinic follow-up after multidisciplinary team meeting discussion

No Evidence for Gamma-Ray Burst/Abell Cluster or Gamma- Ray Burst/Radio-Quiet Quasar Correlations

We examine the recent claims that cosmic gamma-ray bursts are associated with either radio-quiet quasars or Abell clusters. These associations were based on positional coincidences between cataloged quasars or Abell clusters, and selected events from the BATSE 3B catalog of gamma-ray bursts. We use a larger sample of gamma-ray bursts with more accurate positions, obtained by the 3rd Interplanetary Network, to re-evaluate these possible associations. We find no evidence for either.Comment: Accepted for publication in the Astrophysical Journa

Cooling of 2 kW H subscript 2-O subscript 2 fuel cell

An extensive research and development program has been carried out to devise an improved method of removing waste heat of reaction from a developmental 2 kW hydrogen-oxygen fuel cell

The random case of Conley's theorem

The well-known Conley's theorem states that the complement of chain recurrent set equals the union of all connecting orbits of the flow $\phi$ on the compact metric space $X$, i.e. $X-\mathcal{CR}(\phi)=\bigcup [B(A)-A]$, where $\mathcal{CR}(\phi)$ denotes the chain recurrent set of $\phi$, $A$ stands for an attractor and $B(A)$ is the basin determined by $A$. In this paper we show that by appropriately selecting the definition of random attractor, in fact we define a random local attractor to be the $\omega$-limit set of some random pre-attractor surrounding it, and by considering appropriate measurability, in fact we also consider the universal $\sigma$-algebra $\mathcal F^u$-measurability besides $\mathcal F$-measurability, we are able to obtain the random case of Conley's theorem.Comment: 15 page

Development of uniform and predictable battery materials for nickel cadmium aerospace cells Quarterly report, 8 Aug. - 7 Nov. 1968

Sintering of carbonyl nickel powders for nickel cadmium batteries fabricatio