Equator-to-pole temperature differences and the extra-tropical storm track responses of the CMIP5 climate models

This paper aims to understand the physical processes causing the large spread in the storm track projections of the CMIP5 climate models. In particular, the relationship between the climate change responses of the storm tracks, as measured by the 2–6 day mean sea level pressure variance, and the equator-to-pole temperature differences at upper- and lower-tropospheric levels is investigated. In the southern hemisphere the responses of the upper- and lower-tropospheric temperature differences are correlated across the models and as a result they share similar associations with the storm track responses. There are large regions in which the storm track responses are correlated with the temperature difference responses, and a simple linear regression model based on the temperature differences at either level captures the spatial pattern of the mean storm track response as well explaining between 30 and 60 % of the inter-model variance of the storm track responses. In the northern hemisphere the responses of the two temperature differences are not significantly correlated and their associations with the storm track responses are more complicated. In summer, the responses of the lower-tropospheric temperature differences dominate the inter-model spread of the storm track responses. In winter, the responses of the upper- and lower-temperature differences both play a role. The results suggest that there is potential to reduce the spread in storm track responses by constraining the relative magnitudes of the warming in the tropical and polar regions.

A genealogy of the kings of England in papal Avignon: British Library, Egerton MS. 1500

This is one of three articles in eBLJ (2013) dedicated to the "Abreujamen de las estorias", British Library Egerton MS 1500. The other two articles are: Federico Botana,' The Making of "L'Abreujamen de las estorias": British Library Egerton MS 1500', eblj (2013), article 16. Alexander Ibarz, 'The Provenance of the "Abreujamens de las estorias" (London, British Library, Egerton MS. 1500) and the Identification of Scribal Hands (c. 1323)' eblj (2013), article 17. Leglu's article, eblj (2013), article 18, examines the various political agendas that emerge in the depiction of the kings of Britain and England, from Brutus to Edward II.

The history of entrepreneurship: Medieval origins of a modern phenomenon

The origins of enterprise are often associated with the Industrial Revolution, but this article presents evidence of entrepreneurial activities from a much earlier date – the medieval period. Between 1250 and 1500 the church, merchants and members of the royal court all engaged in activities that demonstrated the entrepreneurial characteristics of innovation, risk-taking and judgement. The activities of the prior of Tynemouth and the career of the wool merchant William de la Pole illustrate these developments. By focusing on individuals rather than firms, it is possible to push back the study of entrepreneurship beyond the Industrial Revolution and early-modern trade to a period that witnessed the origins of the modern state.

North Sea archaeologies: a maritime biography, 10,000 BC - AD 1500

North Sea Archaeologies traces the way people engaged with the North Sea from the end of the last ice age, around 10,000 BC, to the close of the Middle Ages, about AD 1500, drawing upon archaeological research from many countries, including the UK, Netherlands, Germany, Denmark, Sweden, Norway, Belgium, and France. It addresses topics which include the first interactions of people with the emerging North Sea, the origin and development of fishing, the creation of coastal landscapes, the importance of islands and archipelagos, the development of seafaring ships and their use by early seafarers and pirates, and the treatment of boats and ships at the end of their useful lives. The study offers a ‘maritime turn’ in Archaeology through the investigation of aspects of human behaviour that have been, to various extents, disregarded, overlooked, or ignored in archaeological studies of the land. The study concludes that the relationship between humans and the sea challenges the frequently invoked dichotomy between pre-modernity and modernity, since many ancient beliefs, superstitions, and practices linked to seafaring and engagement with the sea are still widespread in the modern era.

Small wars and insurgencies in theory and practice, 1500-1850

In early modern times, warfare in Europe took on many diverse and overlapping forms. Our modern notions of ‘regular’ and ‘irregular’ warfare, of ‘major war’ and ‘small war’, have their roots in much greater diversity than such binary notions allow for. While insurgencies go back to time immemorial, they have become conceptually fused with ‘small wars’. This is a term first used to denote special operations, often carried out by military companies formed from special ethnic groups and then recruited into larger armies. In its Spanish form, guerrilla, the term ‘small war’ came to stand for an ideologically-motivated insurgency against the state authorities or occupying forces of another power. There is much overlap between the phenomena of irregular warfare in the sense of special operations alongside regular operations, and irregular warfare of insurgents against the regular forces of a state. This book demonstrates how long the two phenomena were in flux and fed on each other, from the raiding operations of the 16th century to the ‘small wars’ or special operations conducted by special units in the 19th century, which existed alongside and could merge with a popular insurgency. This book is based on a special issue of the journal Small Wars & Insurgencies.

Climate variability and socio-environmental changes in the northern Aegean (NE Mediterranean) during the last 1500 years

We provide new evidence on sea surface temperature (SST) variations and paleoceanographic/paleoenvironmental changes over the past 1500 years for the north Aegean Sea (NE Mediterranean). The reconstructions are based on multiproxy analyses, obtained from the high resolution (decadal to multidecadal) marine record M2 retrieved from the Athos basin. Reconstructed SSTs show an increase from ca. 850 to 950 AD and from ca. 1100 to 1300 AD. A cooling phase of almost 1.5 �C is observed from ca. 1600 AD to 1700 AD. This seems to have been the starting point of a continuous SST warming trend until the end of the reconstructed period, interrupted by two prominent cooling events at 1832 ± 15 AD and 1995 ± 1 AD. Application of an adaptive Kernel smoothing suggests that the current warming in the reconstructed SSTs of the north Aegean might be unprecedented in the context of the past 1500 years. Internal variability in atmospheric/oceanic circulations systems as well as external forcing as solar radiation and volcanic activity could have affected temperature variations in the north Aegean Sea over the past 1500 years. The marked temperature drop of approximately ~2 �C at 1832 ± 15 yr AD could be related to the 1809 АD ‘unknown’ and the 1815 AD Tambora volcanic eruptions. Paleoenvironmental proxy-indices of the M2 record show enhanced riverine/continental inputs in the northern Aegean after ca. 1450 AD. The paleoclimatic evidence derived from the M2 record is combined with a socio-environmental study of the history of the north Aegean region. We show that the cultivation of temperature-sensitive crops, i.e. walnut, vine and olive, co-occurred with stable and warmer temperatures, while its end coincided with a significant episode of cooler temperatures. Periods of agricultural growth in Macedonia coincide with periods of warmer and more stable SSTs, but further exploration is required in order to identify the causal links behind the observed phenomena. The Black Death likely caused major changes in agricultural activity in the north Aegean region, as reflected in the pollen data from land sites of Macedonia and the M2 proxy-reconstructions. Finally, we conclude that the early modern peaks in mountain vegetation in the Rhodope and Macedonia highlands, visible also in the M2 record, were very likely climate-driven.

Virtual Pole from Magnetic Anomaly (VPMA): A procedure to estimate the age of a rock from its magnetic anomaly only

Virtual Pole from Magnetic Anomaly (VPMA) is a new multi-disciplinary methodology that estimates the age of a source rock from its magnetic anomaly, taken directly from available aeromagnetic data. The idea is to use those anomalies in which a strong remanent magnetic component is likely to occur. Once the total magnetization of the anomaly is computed through any of the currently available methods, the line that connects all virtual paleogeographic poles is related with the position, on a paleogeographic projection, of the appropriate age fragment of the APWT curve. We applied this procedure to five (5) well-known magnetic anomalies of the South American plate in SE Brazil, all of them associated to alkaline complexes of Mesozoic age. The apparent ages obtained from VPMA on three of the anomalies where the radiometric age of the source rock is known - Tapira, Araxa and Juquia were inside the error interval of the published ages. The VPMA apparent ages of the other two, where the age of the source rock is not known (Registro and Pariqueracu magnetic anomalies) were geologically coherent. We expect that the application of the VPMA methodology as a reconnaissance geochronological tool may contribute to geological knowledge over continental areas, especially when the source rocks of the magnetic anomalies am unknown or buried below superficial sediments. (C) 2009 Elsevier B.V. All rights reserved.

A late Neoproterozoic paleomagnetic pole for the Congo craton: Tectonic setting, paleomagnetism and geochronology of the Nola dike swarm (Central African Republic)

New structural, geochronological and paleomagnetic data were obtained on dolerite dikes of the Nola region (Central African Republic) at the northern border of the Congo craton. In this region metavolcanic, successions were thrust southward onto the craton during the Panafrican orogenic events. Our structural data reveal at least two structural klippes south of the present-day limits of the Panafrican nappe suggesting that it has once covered the whole Nola region, promoting the pervasive hydrothermal green-schist metamorphism observed in the underlying cratonic basement and also in the intrusive dolerite dikes. Paleomagnetic measurements revealed a stable dual-polarity low-inclination magnetization component in nine dikes (47 samples), carried by pyrrhotite and magnetite. This component corresponds to a paleopole at 304.8 degrees E and 61.8 degrees S (dp = 5.4, dm = 10.7) graded at 2 = 6. Both metamorphism and magnetic resetting were dated by the Ar-40/Ar-39 method on amphibole grains separated from the dikes at 571 +/- 6 Ma. The Nola pole is the first well-dated paleomagnetic pole for the Congo craton between 580 and 550 Ma. It marks a sudden change in direction of the Congo craton apparent polar wander path at the waning stages of the Panafrican orogenic events. (c) 2008 Elsevier B.V. All rights reserved.

Voltammetric characterization of stepped platinum single crystal surfaces vicinal to the (110) pole

Platinum stepped surfaces vicinal to the (1 1 0) crystallographic pole have been investigated voltammetrically in 0.1 M HClO(4) and 0.1 M H(2)SO(4) solutions. Changes in the voltammetric profile with the step density suggest the existence of two types of surface sites, that has been ascribed to linear and bidimensional domains. This result indicates the existence of important restructuring processes that separate the real surface distribution from the nominal one. The electronic properties of the surfaces have been characterized with the CO charge displacement method and the potential of zero total charge has been calculated as a function of the step density. (c) 2009 Elsevier B.V. All rights reserved.

Äldre texter - didaktik och motivation : Didaktisering av ett 1500-talsepos

Syftet med detta arbete är att undersöka huruvida vissa didaktiska tillvägagångssätt kan öka motivationen hos gymnasieelever inför studier av äldre texter samt i vilken utsträckning valfrihet och medbestämmande är viktigt inför arbetet med dessa. Könsrelaterade jämförelser görs. Tidigare forskning presenteras och en empirisk kvantitativ undersökning med enkäter genomförs, baserad på SCAS (Swedish Core Affect Scale) i reducerad form. Ett 1500-talsepos presenteras medelst olika didaktiska metoder för elever som löpande noterar graden av motivation på en niogradig skala bestående av adjektivpar.Studien visar att vissa didaktiska tillvägagångssätt ökar elevers motivation. Berättande samt rörliga bilder i kombination med tal och musik visar sig vara de mest stimulerande metoderna, gärna anknytning till universella teman och perspektiv. Studien visar även att endast vissa elever upplever valfrihet och medbestämmande i samband med arbetet med texten som något positivt.

DC Motor Speed Control via Fuzzy / Pole Placement / PI Controller

This report presents a new way of control engineering. Dc motor speed controlled by three controllers PID, pole placement and Fuzzy controller and discusses the advantages and disadvantages of each controller for different conditions under loaded and unloaded scenarios using software Matlab. The brushless series wound Dc motor is very popular in industrial application and control systems because of the high torque density, high efficiency and small size. First suitable equations are developed for DC motor. PID controller is developed and tuned in order to get faster step response. The simulation results of PID controller provide very good results and the controller is further tuned in order to decrease its overshoot error which is common in PID controllers. Further it is purposed that in industrial environment these controllers are better than others controllers as PID controllers are easy to tuned and cheap. Pole placement controller is the best example of control engineering. An addition of integrator reduced the noise disturbances in pole placement controller and this makes it a good choice for industrial applications. The fuzzy controller is introduce with a DC chopper to make the DC motor speed control smooth and almost no steady state error is observed. Another advantage is achieved in fuzzy controller that the simulations of three different controllers are compared and concluded from the results that Fuzzy controller outperforms to PID controller in terms of steady state error and smooth step response. While Pole placement controller have no comparison in terms of controls because designer can change the step response according to nature of control systems, so this controller provide wide range of control over a system. Poles location change the step response in a sense that if poles are near to origin then step response of motor is fast. Finally a GUI of these three controllers are developed which allow the user to select any controller and change its parameters according to the situation.

Pole placement method using the system matrix transfer function and sparsity

This paper presents a pole placement method using both the augmented Jacobian and the corresponding system transfer function matrices. From the manipulation of these matrices a straightforward approach results to get the coefficients of a non-linear system, whose solution gives the parameters of the stabilizers that can provide a pre-specified minimum damping to the system. (C) 2001 Elsevier B.V. Ltd. All rights reserved.

Pole placement by coordinated tuning of Power System Stabilizers and FACTS-POD stabilizers

This work presents the application of the Decentralized Modal Control method for pole placement in multimachine power systems utilizing FACTS (Flexible AC Transmission Systems), STATCOM (Static Synchronous Compensator) and UPFC (Unified Power Flow Controller) devices. For this, these devices are equipped with supplementary damping controllers, denominated POD ( Power Oscillation Damping), achieving a coordinated project with local controllers (Power System Stabilizers - PSS). Comparative analysis on the function of damping of the FACTS, STATCOM and UPFC is performed using the New England System that has 10 generators, 39 buses and 46 transmission lines. (c) 2011 Elsevier Ltd. All rights reserved.

Robust state-derivative pole placement LMI-based designs for linear systems

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