Review of the Fusion Materials Research Program

This report presents the results and recommendations of the deliberations of the U.S. Department of Energy (DOE) Fusion Energy Sciences Advisory Committee Panel on the Review of the Fusion Materials Research Program carried out during 1998. Metrics evaluated included evidence of recognition, publications per worker, new people attracted to the work and significance of recent accomplishments.     

Linking rural livelihood resilience and food security: an international challenge

In many parts of the world, rural livelihoods are characterized by a high degree of vulnerability to climate change, market volatility, and political unrest. Increasingly, the concept of resilience is being used to inform development initiatives aimed at building the capacity of rural households and communities to cope, adapt, and transform in the face of diverse shocks and stressors. There remain, however, significant challenges to mainstreaming resilience thinking into food and nutrition security policy and programming, primarily because the concept is best understood as being embedded within dynamic and highly contextual processes that can be interpreted differently by various parties. This Special Section of Food Security presents international case studies exploring the vulnerability of rural livelihoods and the initiatives proposed to build resilience, providing valuable insights into the practical challenges to assessing resilience in different contexts. Through different applications of the resilience concept, these case studies highlight the key roles played by broader social, institutional, and governance contexts in affecting food and nutrition security. The need to better supplement the development of reliable metrics for assessing resilience with richer and more context-specific narratives is also highlighted.     

Minimum vertical load on masonry walls – a realistic view / Mindestauflast auf Mauerwerkswänden – eine realitätsnahe Betrachtung

To transfer bending moments in building components consisting of a material without tensile strength always requires a simultaneously acting normal force. Accordingly, masonry walls exposed to horizontal loads (e.g. wind) require a minimum vertical load, so that the resultant stress at the mid‐height of the wall remains the same within the cross‐section. As part of the A2 amendment to DIN EN 1996‐3/NA, this verification of walls subjected to low vertical loads, such as outer walls on the top floor exposed to high wind load was implemented in the National Annex. Part 3 of DIN EN 1996‐3 includes a similar standard regulation for verification of the minimum vertical load, which is based on an arch effect within the wall cross‐section. Based on this technical background and taking into account the main influencing parameters, a verification model is presented here which realistically describes the load‐bearing behaviour of unreinforced masonry walls subjected primarily to bending. Apart from the bending moments due to wind load, an initial eccentricity of the wall as well as second order effects due to wall deformations also have to be taken into account. In addition, a simple approximation equation is provided for the practical determination of the required minimum vertical load.     

Experimental Investigation of the Impact of Cathode Grade on Sludge Formation at the Cathode Block-Aluminum Interface of Hall–Héroult Cells

Metallurgical and Materials Transactions B - The presence of resistive sludge on the cathode surface in Hall–Héroult cells can increase the aluminum production costs and reduces cell...     

A Mathematical Model of the Vagally Driven SA Nodal Pacemaker

A model is developed for the vagal control of SA nodal activity in the heart and consists essentially of a modified Bonhoeffer-Van der Pol (BVP) model of the ``free-running' SA node and a lumped model of the neural terminations in that region. The model is capable of mimicking both the driven transient behavior of the node in terms of pacemaker and inhibition curves, as well as steady-state entrainment phenomena. The model data also agree very well with experimental data from dog experiments performed in our laboratory. The model is described by a set of nonlinear, third-order, ordinary differential equations and provides a relatively uncomplicated functional model of heart period changes due to vagal stimulation patterns.     

Die qualitativen Reaktionen des Wasserstoffsuperoxyds und deren Anwendbarkeit bei Gegenwart von Milch

Ohne ZusammenfassungMitteilung aus dem chemischen Institut der Königl. Tierärztlichen Hochschule zu Hannover.     

Wanderwellen an unsymmetrischen Leitungen

Zusammenfassung In der Arbeit wird nachgewiesen, daß Wanderwellen in vielen Fällen sich längs einer Doppelleitung nicht in symmetrischer Spannungsverteilung ausbreiten. Trotzdem hat in solchen Fällen die Spannung zwischen den Leitern die durch Versuche und Oszillogramm gegebene übliche Form. Die beiden Leiter dagegen schwingen mit ihrer Spannung gegen Erde in verwickelter Form, die durch Oszillogramme in der vorliegenden Arbeit dargelegt ist und in der Wanderwellentheorie begründet wurde.Die Arbeit wurde im elektrotechnischen Institut der Technischen Hochschule Aachen unter Leitung von Herrn Prof. Dr.-Ing. W. Rogowski ausgeführt. Für seine wertvollen Anregungen bin ich Herrn Prof. Rogowski zu großrn Dank verpflichtet. Auch der Notgemeinschaft der Deutschen Wissenschaft sei für ihre tatkräftige Unterstützung bestens gedankt.     

Über Winkelfehler von Hochspannungswiderständen

Ohne Zusammenfassung