881 research outputs found
Fluid logic devices: a review
Background study of work connected with this report entailed the
collection of a large number of specialised and general technical
publications concerning the techniques and applications of fluid
computing. General conclusions from these investigations are that,
in Russia and America, this science is very advanced and considered to
be of great significance, especially where pure fluid logic devices are
concerned. The purpose of this survey is to enable the reader to assess
the quality and magnitude of work done by other academic institutions,
and also to show with what importance this science is viewed elsewhere.
It must be realized, however, that general description and discussion
of available bibliography is the only assessment possible, as work of a
military nature has not been released
Position transducers for numerically controlled machine tools
The paper covers the basic text book theory of all forms of position
transducer used on commercial numerically controlled machine tools. Some
attempt is made to categorise and indicate the scope and usage of these
devices. The descriptions deliberately set out to explain this essentially
electrical topic in a manner not requiring expert electrical knowledge
Automatic assembly design project 1968/9: report of technical survey committee
An Industrial survey has been carried out to
determine the desired features of an automatic
as machine.
A questionnaire was circulated to industry and
the results of the 38% response obtained were
analysed and plotted. From these, conclusions
were drawn as to the industrial requirements of
an assembly machine
Hydrogen Isocyanide in Comet 73P/Schwassmann-Wachmann (Fragment B)
We present a sensitive 3-sigma upper limit of 1.1% for the HNC/HCN abundance
ratio in comet 73P/Schwassmann-Wachmann (Fragment B), obtained on May 10-11,
2006 using Caltech Submillimeter Observatory (CSO). This limit is a factor of
~7 lower than the values measured previously in moderately active comets at 1
AU from the Sun. Comet 73P/Schwassmann-Wachmann was depleted in most volatile
species, except of HCN. The low HNC/HCN ratio thus argues against HNC
production from polymers produced from HCN. However, thermal degradation of
macromolecules, or polymers, produced from ammonia and carbon compounds, such
as acetylene, methane, or ethane appears a plausible explanation for the
observed variations of the HNC/HCN ratio in moderately active comets, including
the very low ratio in comet 73P/Schwassmann-Wachmann reported here. Similar
polymers have been invoked previously to explain anomalous 14N/15N ratios
measured in cometary CN.Comment: 6 pages, 5 figures, 2 table
Protection, interlocks and diagnostics
When designing any power converter it is essential to assess and incorporate adequate protection. The main objective is to offer a solution which is safe, reliable and repairable and that achieves its specification within budget. The level of protection found within each converter varies widely and will depend on the topology employed, its application and rating. This document is a guide to the types of protection engineers should consider mainly when designing power converters, as protection added during construction or after installation will always be expensive
A qualitative exploration of the experiences of pregnant women living with obesity and accessing antenatal care
Women are advised to optimise weight before pregnancy. However, many are either already living with overweight or obesity prior to becoming pregnant, increasing the risks for adverse outcomes. Health care professionals (HCP) are responsible for advising women of risks throughout and following pregnancy. However, midwives find broaching the conversation around maternal obesity difficult. This difficulty may be due to insufficient knowledge regarding the management of obesity during pregnancy or because they do not wish to offend. This study explored the experiences of accessing antenatal care in pregnant women living with obesity. Seventeen women completed a semi-structuredinterview. Transcripts were analysed thematically. Four themes were developed:1) antenatal care is inconsistent, 2)additional support is needed, 3) women feel judged about their weight, and 4) weight cycling is highly prevalent. Findings suggest that pregnant women living with obesity often experience weight bias from HCPs, feel judged because of their weight and are left feeling confused andoverlooked. Women reported inconsistencies in advice and care offered,and acknowledged a lack of continuity of care throughout pregnancy. We call for an urgent need for further multidisciplinary training to address the concerns, experiences and needs of pregnant women living with obesity
Abundance Measurements of Titan's Stratospheric HCN, HCN, CH, and CHCN from ALMA Observations
Previous investigations have employed more than 100 close observations of
Titan by the Cassini orbiter to elucidate connections between the production
and distribution of Titan's vast, organic-rich chemical inventory and its
atmospheric dynamics. However, as Titan transitions into northern summer, the
lack of incoming data from the Cassini orbiter presents a potential barrier to
the continued study of seasonal changes in Titan's atmosphere. In our previous
work (Thelen et al., 2018), we demonstrated that the Atacama Large
Millimeter/submillimeter Array (ALMA) is well suited for measurements of
Titan's atmosphere in the stratosphere and lower mesosphere (~100-500 km)
through the use of spatially resolved (beam sizes <1'') flux calibration
observations of Titan. Here, we derive vertical abundance profiles of four of
Titan's trace atmospheric species from the same 3 independent spatial regions
across Titan's disk during the same epoch (2012 to 2015): HCN, HCN,
CH, and CHCN. We find that Titan's minor constituents exhibit large
latitudinal variations, with enhanced abundances at high latitudes compared to
equatorial measurements; this includes CHCN, which eluded previous
detection by Cassini in the stratosphere, and thus spatially resolved abundance
measurements were unattainable. Even over the short 3-year period, vertical
profiles and integrated emission maps of these molecules allow us to observe
temporal changes in Titan's atmospheric circulation during northern spring. Our
derived abundance profiles are comparable to contemporary measurements from
Cassini infrared observations, and we find additional evidence for subsidence
of enriched air onto Titan's south pole during this time period. Continued
observations of Titan with ALMA beyond the summer solstice will enable further
study of how Titan's atmospheric composition and dynamics respond to seasonal
changes.Comment: 15 pages, 16 figures, 2 tables. Accepted for publication in Icarus,
September 201
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