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What do others think is the point of design and technology education?
As a result of a national curriculum review in England (Department for Education [DfE], 2011), a new curriculum for design and technology (D&T) is being taught in secondary schools from September 2014 (Department of Education [DoE], 2013a). This curriculum is compulsory for a decreasing number of schools; two potential consequences are the nature of D&T in secondary schools changing to reflect local perceptions of the subject and maybe D&T being removed from the curriculum completely. The pressure on D&T’s curriculum content is likely to come from different stakeholders such as senior school leaders, D&T teachers, and pupils. D&T school departments could respond to this pressure by adapting the curriculum to popularise the subject or produce high exam results with a consequence that much of the subject’s value is lost. This paper reports on a small research project conducted in two secondary schools where stakeholder representatives were interviewed to identify their values of D&T. These different stakeholders were interviewed using the active interview method (Holstein & Gubrium, 1995), coded following Aurebach and Silverstein’s method (2003) and their values compared to Hardy’s values framework (Hardy, 2013b). Analysis shows most stakeholders believe a key value of D&T is to provide ‘practical life skills’ (Hardy, p.226), whilst only one recognizes that learning in D&T involves ‘identifying problems to be solved’. The outcomes from the research are being used to support critically reflective conversations within both D&T departments (Zwozdiak-Myers, 2012) framing their evaluation of their local curriculum and making changes to their curriculum
Omnidirectional joint Patent
Cord restraint system for pressure suit joint
The devil in the deep: Expanding the known habitat of a rare and protected fish
The accepted geographic range of a species is related to both opportunity and effort in sampling that range. In deepwater ecosystems where human access is limited, the geographic ranges of many marine species are likely to be underestimated. A chance recording from baited cameras deployed on deep uncharted reef revealed an eastern blue devil fish (Paraplesiops bleekeri) at a depth of 51 m and more than 2 km further down the continental shelf slope than previously observed. This is the first verifiable observation of eastern blue devil fish, a protected and endemic southeastern Australian temperate reef species, at depths greater than the typically accepted depth range of 30 m. Knowledge on the ecology of this and many other reef species is indeed often limited to shallow coastal reefs, which are easily accessible by divers and researchers. Suitable habitat for many reef species appears to exist on deeper offshore reefs but is likely being overlooked due to the logistics of conducting research on these often uncharted habitats. On the basis of our observation at a depth of 51 m and observations by recreational fishers catching eastern blue devil fishes on deep offshore reefs, we suggest that the current depth range of eastern blue devil fish is being underestimated at 30 m. We also observed several common reef species well outside of their accepted depth range. Notably, immaculate damsel (Mecaenichthys immaculatus), red morwong (Cheilodactylus fuscus), mado (Atypichthys strigatus), white-ear (Parma microlepis) and silver sweep (Scorpis lineolata) were abundant and recorded in a number of locations at up to a depth of at least 55 m. This underestimation of depth potentially represents a large area of deep offshore reefs and micro habitats out on the continental shelf that could contribute to the resilience of eastern blue devil fish to extinction risk and contribute to the resilience of many reef species to climate change
Nonlocal Effects of Partial Measurements and Quantum Erasure
Partial measurement turns the initial superposition not into a definite
outcome but into a greater probability for it. The probability can approach
100%, yet the measurement can undergo complete quantum erasure. In the EPR
setting, we prove that i) every partial measurement nonlocally creates the same
partial change in the distant particle; and ii) every erasure inflicts the same
erasure on the distant particle's state. This enables an EPR experiment where
the nonlocal effect does not vanish after a single measurement but keeps
"traveling" back and forth between particles. We study an experiment in which
two distant particles are subjected to interferometry with a partial "which
path" measurement. Such a measurement causes a variable amount of correlation
between the particles. A new inequality is formulated for same-angle
polarizations, extending Bell's inequality for different angles. The resulting
nonlocality proof is highly visualizable, as it rests entirely on the
interference effect. Partial measurement also gives rise to a new form of
entanglement, where the particles manifest correlations of multiple
polarization directions. Another novelty in that the measurement to be erased
is fully observable, in contrast to prevailing erasure techniques where it can
never be observed. Some profound conceptual implications of our experiment are
briefly pointed out.Comment: To be published in Phys. Rev. A 63 (2001). 19 pages, 12 figures,
RevTeX 3.
MACHO Mass Determination Based on Space Telescope Observation
We investigate the possibility of lens mass determination for a caustic
crossing microlensing event based on a space telescope observation. We
demonstrate that the parallax due to the orbital motion of a space telescope
causes a periodic fluctuation of the light curve, from which the lens distance
can be derived. Since the proper motion of the lens relative to the source is
also measurable for a caustic crossing event, one can find a full solution for
microlensing properties of the event, including the lens mass. To determine the
lens mass with sufficient accuracy, the light curve near the caustic crossing
should be observed within uncertainty of 1%. We argue that the Hubble
Space Telescope observation of the caustic crossing supplied with ground-based
observations of the full light curve will enable us to determine the mass of
MACHOs, which is crucial for understanding the nature of MACHOs.Comment: 9 pages + 3 figures, accepted for publication in ApJ Letter
An improved calculation of the isospin-symmetry-breaking corrections to superallowed Fermi beta decay
We report new shell-model calculations of the isospin-symmetry-breaking
correction to superallowed nuclear beta decay. The most important improvement
is the inclusion of core orbitals, which are demonstrated to have a significant
impact on the mismatch in the radial wave functions of the parent and daughter
states. We determine which core orbitals are important to include from an
examination of measured spectroscopic factors in single-nucleon pick-up
reactions. We also examine the new radiative-correction calculation by Marciano
and Sirlin and, by a simple reorganization, show that it is possible to
preserve the conventional separation into a nucleus-independent inner radiative
term and a nucleus-dependent outer term. We tabulate new values for the three
theoretical corrections for twenty superallowed transitions, including the
thirteen well-studied cases. With these new correction terms the corrected Ft
values for the thirteen cases are statistically consistent with one another and
the anomalousness of the 46V result disappears. These new calculations lead to
a lower average Ft value and a higher value of Vud. The sum of squares of the
top-row elements of the CKM matrix now agrees exactly with unitarity.Comment: 15 pages, 2 postscript figures, revtex
Flight evaluation of the STOL flare and landing during night operations
Simulated instrument approaches were made to Category 1 minimums followed by a visual landing on a 100 x 1700 ft STOL runway. Data were obtained for variations in the aircraft's flare response characteristics and control techniques and for different combinations of aircraft and runway lighting and a visual approach slope indication. With the complete aircraft and runway lighting and visual guidance no degradation in flying qualities or landing performance was observed compared to daylight operations. elimination of the touchdown zone floodlights or the aircraft landing lights led to somewhat greater pilot workload; however, the landing could still be accomplished successfully. Loss of both touchdown zone and aircraft landing lights led to a high workload situation and only a marginally adequate to inadequate landing capability
Discriminating quantum-optical beam-splitter channels with number-diagonal signal states: Applications to quantum reading and target detection
We consider the problem of distinguishing, with minimum probability of error,
two optical beam-splitter channels with unequal complex-valued reflectivities
using general quantum probe states entangled over M signal and M' idler mode
pairs of which the signal modes are bounced off the beam splitter while the
idler modes are retained losslessly. We obtain a lower bound on the output
state fidelity valid for any pure input state. We define number-diagonal signal
(NDS) states to be input states whose density operator in the signal modes is
diagonal in the multimode number basis. For such input states, we derive series
formulas for the optimal error probability, the output state fidelity, and the
Chernoff-type upper bounds on the error probability. For the special cases of
quantum reading of a classical digital memory and target detection (for which
the reflectivities are real valued), we show that for a given input signal
photon probability distribution, the fidelity is minimized by the NDS states
with that distribution and that for a given average total signal energy N_s,
the fidelity is minimized by any multimode Fock state with N_s total signal
photons. For reading of an ideal memory, it is shown that Fock state inputs
minimize the Chernoff bound. For target detection under high-loss conditions, a
no-go result showing the lack of appreciable quantum advantage over coherent
state transmitters is derived. A comparison of the error probability
performance for quantum reading of number state and two-mode squeezed vacuum
state (or EPR state) transmitters relative to coherent state transmitters is
presented for various values of the reflectances. While the nonclassical states
in general perform better than the coherent state, the quantitative performance
gains differ depending on the values of the reflectances.Comment: 12 pages, 7 figures. This closely approximates the published version.
The major change from v2 is that Section IV has been re-organized, with a
no-go result for target detection under high loss conditions highlighted. The
last sentence of the abstract has been deleted to conform to the arXiv word
limit. Please see the PDF for the full abstrac
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