Vibration of a high-altitude tethered balloon with application to climate engineering

A balloon tethered at an altitude of 20 km could deliver a particulate cloud leading to global cooling. Tethering a balloon at this altitude poses significant problems with respect to vibration and stability, especially in regions of high wind. No-one has ever proposed, yet alone launched, a balloon at an altitude of 20 km tethered to the ground. Owing to wind, the tether needs to be 23 km in length and is to be fixed to a ship at sea or on land in equatorial regions. Whilst the balloon at 20 km is subject to relatively modest wind conditions, at jet stream altitudes (10km) the tether will experience much higher wind loadings, not only because of the high wind speeds of up to 300 km / hr but also because of the high air density. A tether of circular cross section in these high winds will be subject to horizontal and downward drag forces that would bring the aerostat down. For this reason it is advantageous to consider a self-aligning tether of an aerodynamic cross section whereby it is possible to reduce the drag substantially. One disadvantage of a non-circular tether is the possibility of flutter and galloping instabilities. It is reasonably straightforward to model these phenomena for short lengths of aerofoil, but the situation becomes more complex for a 20 km tensioned tether with large deflection and curvature, variable wind speed, variable air density and variable tension. Analysis using models of infinite length are used to establish the stability at a local scale where the tension, aerodynamic and geometric properties are considered constant. Dispersion curve analysis is useful here. But for dynamics on a long-wavelength scale (several km) then a full non-linear analysis is required. This non-linear model can be used to establish the local values of tension appropriate for the dispersion analysis. This keynote presentation will give some insight into these issues.

Hör-Spiele/Laut-Sprecher. Aspekte medialer Hörerziehung an der Schule für Geistigbehinderte

Sonderpädagogisch orientierter Unterricht thematisiert Hören auf dreierlei Weise: Innerhalb von Artikulationsförderung (Lautproduktion) geht es um die Unterscheidung, Wiederholung einzelner Phoneme oder Phonemgruppen, deren Zusammenbinden zu Wörtern, Sätzen usw. und damit um Aufbau und Stabilisierung auditiv-motorischer Regulationskreise bei der Sprachproduktion. In der Wahrnehmungsförderung geht es um Unterscheidung und Benennung von Klängen oder Geräuschen. Ansätze der Medienerziehung heben den Unterschied konservierter/vermittelter und tatsächlicher Klangereignisse hervor. In allen drei Perspektiven geht es um die Ausbildung, Verbesserung, Schulung des Hörorgans und der darauf bezogenen kognitiven und sprachlichen Leistungen. Was dabei allerdings vernachlässigt bleibt ist der ursprüngliche Weltbezug des Hörens. Denn wir hören nicht an sich, sondernd stets irgendwas. Der Klangcharakter der Welt (Schläft ein Lied in allen Dingen) ist nicht eine unverbindliche Metapher sondern korrespondiert mit unserer Fähigkeit zu hören. Nachfolgend wird deshalb vorgeschlagen, Hören als Anliegen des Sachunterrichts zu begreifen und im Rahmen einer ästhetischen Elementarerziehung zu thematisieren. Einige Unterrichtsbeispiele illustrieren, welchen Ertrag eine solche Sicht hat. Dabei soll auch deutlich werden, daß Hörerziehung kein Additivum sein kann, sondern wichtiges Glied schulischer Kommunikationsförderung. (DIPF/Orig.)

Communication, recognition and social work: Aligning the ethical theories of Habermas and Honneth

The modern world is replete with ethical challenges of Orwellian proportions. The violation of human rights and misrecognition of identities are two of the most pressing examples. In this paper, the ethical theories of Habermas and Honneth are aligned as a way of addressing these specific challenges within social work. It is suggested that these theories are complementary, mutually rectifying and concordant at the meta-ethical level of analysis. The alignment is also justified, pargmatically, through the construction of three hypothetical vignettes demonstrating different kinds of practice dilemmas. The need for egalitarian communication and the imperative to recognise human identity in all its dimensions subsequently emerge as the two foundation stones for ethical deliberation in social work.

Aligning conservation priorities across taxa in Madagascar with high-resolution planning tools

Globally, priority areas for biodiversity are relatively well known, yet few detailed plans exist to direct conservation action within them, despite urgent need. Madagascar, like other globally recognized biodiversity hot spots, has complex spatial patterns of endemism that differ among taxonomic groups, creating challenges for the selection of within-country priorities. We show, in an analysis of wide taxonomic and geographic breadth and high spatial resolution, that multitaxonomic rather than single-taxon approaches are critical for identifying areas likely to promote the persistence of most species. Our conservation prioritization, facilitated by newly available techniques, identifies optimal expansion sites for the Madagascar government's current goal of tripling the land area under protection. Our findings further suggest that high-resolution multitaxonomic approaches to prioritization may be necessary to ensure protection for biodiversity in other global hot spots.

Out of tune: the dangers of aligning proxy archives

Tuning is a widespread technique to combine, date and interpret multiple fossil proxy archives through aligning supposedly synchronous events between the archives. The approach will be reviewed by discussing a number of literature examples, ranging from peat and tephra layers to orbital tuning and d¹⁸O series from marine and ice deposits. Potential problems will be highlighted such as the dangers of circular reasoning and unrecognised chronological uncertainties, and some solutions suggested. Fossil proxy research could become enhanced if tuning were approached in a more quantitative, reliable and objective way, and especially if individual proxy archives were non-tuned and kept on independent time-scales.

Self-aligning wireless link using modulated backscatter

A self-tracking (aligning) radio communications system based on the principle of modulated backscatter detection is presented here. Using amplitude-modulated backscatter from a co-operating target, a modified IQ demodulation scheme is used to reproduce automatically and in real time both the received and conjugate of the received phase of an incoming signal. The phase conjugated demodulated IF signal can have incoming backscattered data removed and new data are inserted before being up-converted using IQ single side-band generation so that retro-directive re-transmission can be made to occur. In the absence of the backscattered modulation signal, no phase conjugation and hence no retro-directed re-transmission can occur. The system reported is therefore inherently self-authenticating a facility not readily available from previously reported retro-directive self-tracking systems. © 2010 © The Institution of Engineering and Technology.

Simultaneous optical and X-ray observations of flares and rotational modulation on the RS CVn binary HR 1099 (V711 Tau) from the MUSICOS 1998 campaign

We present simultaneous and continuous observations of the Halpha, Hbeta, He I D-3, Na I D-1,D-2 doublet and the Ca II H&K lines for the RS CVn system HR 1099. The spectroscopic observations were obtained during the MUSICOS 1998 campaign involving several observatories and instruments, both echelle and long-slit spectrographs. During this campaign, HR 1099 was observed almost continuously for more than 8 orbits of 2.(d)8. Two large optical flares were observed, both showing an increase in the emission of Halpha, Ca II H K, Hbeta and He I D-3 and a strong filling-in of the Na I D-1, D-2 doublet. Contemporary photometric observations were carried out with the robotic telescopes APT-80 of Catania and Phoenix-25 of Fairborn Observatories. Maps of the distribution of the spotted regions on the photosphere of the binary components were derived using the Maximum Entropy and Tikhonov photometric regularization criteria. Rotational modulation was observed in Halpha and He I D-3 in anti-correlation with the photometric light curves. Both flares occurred at the same binary phase (0.85), suggesting that these events took place in the same active region. Simultaneous X-ray observations, performed by ASM on board RXTE, show several flare-like events, some of which correlate well with the observed optical flares. Rotational modulation in the X-ray light curve has been detected with minimum flux when the less active G5 V star was in front. A possible periodicity in the X-ray flare-like events was also found.

Understanding how HR systems work: the role of HR philosophy and HR processes

Despite the proliferation of studies of HR systems, there are still substantial gaps in our understanding
of how such systems actually work. This article, by focusing on the neglected areas of HR philosophy
and HR processes in the composition of HR systems, and by using a qualitative, employee-centred
approach in the collection and analysis of data, provides new insights into the working of HR systems.
Using data from interviews with 56 knowledge workers employed in the information and
communications technology sector in Ireland and the UK, we explore employee-level reactions to two
different types of HR systems. We highlight the various ways in which HR processes interact with HR
practices and the different outcomes that may result, and we identify the key role of HR philosophy in
HR system operation.

SPATIALLY RESOLVED SPECTROSCOPY OF THE EXOPLANET HR 8799 c

HR 8799 is a multi-planet system detected in direct imaging, with three companions known so far. Here, we present spatially resolved Very Large Telescope/NACO 3.88-4.10 µm spectroscopy of the middle planet, HR 8799 c, which has an estimated mass of ~10 M Jup, temperature of ~1100 K, and projected separation of 38 AU. The spectrum shows some differences in the continuum from existing theoretical models, particularly longwards of 4 µm, implying that detailed cloud structure or non-equilibrium conditions may play an important role in the physics of young exoplanetary atmospheres.