Continuous Monitoring of Ground-Motion Parameters

We applied a time-domain method to continuously monitor groundmotion parameters to facilitate rapid determination of the geographical distribution of ground motion and earthquake parameters. This approach minimizes the impact of the sudden increase in the worload on data acquisition facilities and streamlines the operation of a seismic network, especially during a complex earthquakes sequence. The incoming continuous time series is processed with the use of various time-domain recursive filters to compute ground-motion velocity, acceleration, energy, Wood-Anderson seismograms, and narrow-band responses at 0.3, 1.0, and 3.0 sec, which are used for computation of response spectral amplitudes. The method is implemented in the Southern California Digital Seismic Network. The method can be implemented at every field station, which would make it possible to process the time series locally and continuously telemeter desired amplitude parameters with sufficient accuracy from a field station to multiple users through a relatively low data-rate communication line (e.g., regular telephone line or limited bandwidth satellite link)

CyberShake-derived ground-motion prediction models for the Los Angeles region with application to earthquake early warning

Real-time applications such as earthquake early warning (EEW) typically use empirical ground-motion prediction equations (GMPEs) along with event magnitude and source-to-site distances to estimate expected shaking levels. In this simplified approach, effects due to finite-fault geometry, directivity and site and basin response are often generalized, which may lead to a significant under- or overestimation of shaking from large earthquakes (M > 6.5) in some locations. For enhanced site-specific ground-motion predictions considering 3-D wave-propagation effects, we develop support vector regression (SVR) models from the SCEC CyberShake low-frequency (415 000 finite-fault rupture scenarios (6.5 ≤ M ≤ 8.5) for southern California defined in UCERF 2.0. We use CyberShake to demonstrate the application of synthetic waveform data to EEW as a ‘proof of concept’, being aware that these simulations are not yet fully validated and might not appropriately sample the range of rupture uncertainty. Our regression models predict the maximum and the temporal evolution of instrumental intensity (MMI) at 71 selected test sites using only the hypocentre, magnitude and rupture ratio, which characterizes uni- and bilateral rupture propagation. Our regression approach is completely data-driven (where here the CyberShake simulations are considered data) and does not enforce pre-defined functional forms or dependencies among input parameters. The models were established from a subset (∼20 per cent) of CyberShake simulations, but can explain MMI values of all >400 k rupture scenarios with a standard deviation of about 0.4 intensity units. We apply our models to determine threshold magnitudes (and warning times) for various active faults in southern California that earthquakes need to exceed to cause at least ‘moderate’, ‘strong’ or ‘very strong’ shaking in the Los Angeles (LA) basin. These thresholds are used to construct a simple and robust EEW algorithm: to declare a warning, the algorithm only needs to locate the earthquake and to verify that the corresponding magnitude threshold is exceeded. The models predict that a relatively moderate M6.5–7 earthquake along the Palos Verdes, Newport-Inglewood/Rose Canyon, Elsinore or San Jacinto faults with a rupture propagating towards LA could cause ‘very strong’ to ‘severe’ shaking in the LA basin; however, warning times for these events could exceed 30 s

CyberShake-derived ground-motion prediction models for the Los Angeles region with application to earthquake early warning

Real-time applications such as earthquake early warning (EEW) typically use empirical ground-motion prediction equations (GMPEs) along with event magnitude and source-to-site distances to estimate expected shaking levels. In this simplified approach, effects due to finite-fault geometry, directivity and site and basin response are often generalized, which may lead to a significant under- or overestimation of shaking from large earthquakes (M>6.5) in some locations. For enhanced site-specific ground-motion predictions considering 3-D wave-propagation effects, we develop support vector regression (SVR) models from the SCEC CyberShake low-frequency (415000 finite-fault rupture scenarios (6.5 ≤ M ≤ 8.5) for southern California defined in UCERF 2.0. We use CyberShake to demonstrate the application of synthetic waveform data to EEW as a ‘proof of concept', being aware that these simulations are not yet fully validated and might not appropriately sample the range of rupture uncertainty. Our regression models predict the maximum and the temporal evolution of instrumental intensity (MMI) at 71 selected test sites using only the hypocentre, magnitude and rupture ratio, which characterizes uni- and bilateral rupture propagation. Our regression approach is completely data-driven (where here the CyberShake simulations are considered data) and does not enforce pre-defined functional forms or dependencies among input parameters. The models were established from a subset (∼20per cent) of CyberShake simulations, but can explain MMI values of all>400 k rupture scenarios with a standard deviation of about 0.4 intensity units. We apply our models to determine threshold magnitudes (and warning times) for various active faults in southern California that earthquakes need to exceed to cause at least ‘moderate', ‘strong' or ‘very strong' shaking in the Los Angeles (LA) basin. These thresholds are used to construct a simple and robust EEW algorithm: to declare a warning, the algorithm only needs to locate the earthquake and to verify that the corresponding magnitude threshold is exceeded. The models predict that a relatively moderate M6.5-7 earthquake along the Palos Verdes, Newport-Inglewood/Rose Canyon, Elsinore or San Jacinto faults with a rupture propagating towards LA could cause ‘very strong' to ‘severe' shaking in the LA basin; however, warning times for these events could exceed 30

The Politics of Airpower in US-China relations 1928-1941

This thesis looks at the politics of airpower in US-China relations in 1928-1941, in particular the question of aviation assistance to the Nationalists. Since World War II, American historians have asserted that before Pearl Harbor, Americans helped the Chinese to improve their air force to resist Japan. The thesis finds, however, that trade not aid dominated the approach of the US government and private individuals towards China and that Chiang wanted an air force to use against his internal enemies, not Japan. Moreover, the Roosevelt Administration consistently treated China’s airpower needs as secondary to those of Britain or the US military. In the interwar years, China and the United States had less to do with each other than with other allies. In 1933-1935 Chiang preferred an official Italian air mission to an unofficial American one. After the outbreak of the Sino-Japanese war in 1937, Stalin sent massive air assistance to China which eclipsed the influence of American aircraft salesmen and advisers. In 1938-1939 President Roosevelt promoted the sale of aircraft to Britain and France, believing that large modern air fleets would deter Germany from aggression against its European neighbours. China was far down his list of priorities. In 1939 the Administration adopted a policy of promoting aircraft sales to China which was comparable to that adopted for its European allies. By encouraging aircraft sales to the Nationalists, the Administration hoped to boost China’s resistance so that Japan would remain ‘bogged down’ in China instead of attacking the Asian colonies of European allies. In the winter of 1940-1941, the formation of a mercenary air force, the American Volunteer Group (AVG) was associated with this strategy. As this thesis reveals, British and Chinese officials decided to base the AVG in Burma to enhance the air defence of British territory in the Far East. Thus the AVG became unofficial aid primarily for Britain. Soon after Pearl Harbor, the American press began to treat the AVG as symbol of Sino-American friendship. The group became known as the Flying Tigers and the original reasons for its formation were buried under layers of propaganda which have distorted the historical record ever since

« Looking with seeing eyes » : la construction du lien humain dans « For Love of the Hills » (1905) et « His Smile » (1921), deux nouvelles de Susan Glaspell

« For Love of The Hills » et « His Smile », deux nouvelles écrites par Susan Glaspell au début du XXe siècle, illustrent et mettent en question la notion de « lien humain » centrale à l’œuvre de l’auteur. Bien que les nouvelles aient été écrites à 15 ans d’écart et présentent en cela de nombreuses différences en termes de style et de traitement de la thématique du lien humain, elles reposent toutes deux sur la notion de « vue/vision » qui en est la pierre angulaire diégétique et linguistique. Cet article propose d’étudier les techniques de caractérisation qui s’ajoutent à l’emploi massif du champ lexical du « voir » pour représenter des personnages oscillant entre aveuglement et vision. Les phrases finales des nouvelles feront l’objet d’une étude particulière : toutes deux fins heureuses et rédemptrices en apparence, elles n’ont pas la même structure et le changement de voix narrative qu’elles présentent n’a pas la même fonction. En 15 ans, l’auteur a évolué dans sa façon de traiter le « lien humain ».“For Love of The Hills” and “His Smile” illustrate and question the notion of “human connectedness” that American author Susan Glaspell cherishes. Though the two short stories were respectively written in 1905 and 1921, and show much variation in terms of style and theme, they both hinge upon the notion of “sight/vision” ‒ be it linguistically or diegetically ‒ in the treatment of the necessary connection between human beings. The article will study the stylistic techniques of characterisation that add to the massive lexical field of sight in order to describe protagonists that sway between blindness and vision. Particular attention will be given to the happy redemptive endings of these stories, which vary in terms of structure and narrative voice, and show an evolution in the author’s handling of the subject

Genres et jeux de regards dans Trifles, pièce en un acte, et son adaptation en nouvelle ‘A Jury of her Peers’

Cet article propose d’étudier la manifestation linguistique du regard et du point de vue dans deux œuvres de Susan Glaspell : Trifles (1916), pièce en un acte, et son adaptation en nouvelle par le même auteur, « A Jury of her Peers » (1917). C’est l’entrelacs du genre d’investigation et des champs génériques narratif et théâtral qui, à la fois, provoque des similitudes dans le traitement du regard, mais aussi et surtout des différences : l’utilisation des verbes LOOK, SEE et SEEM d’une part, et la forme BE+V-ING d’autre part, feront l’objet d’une étude comparative puisque leur emploi semble conditionné par le genre discursif. Nous relierons ces phénomènes linguistiques à la stratégie narrative à l’œuvre dans les deux textes et à l’interprétation de la critique sociétale de Susan Glaspell.This article focuses on the linguistic treatment of vision and point of view in Susan Glaspell’s masterpieces Trifles (1916) and « A Jury of her Peers » (1917). They belong to different generic fields – respectively drama and narrative ‒, and meet another genre ‒ detective fiction‒, as they happen to deal with a crime scene. Intertwining these genres causes similarities but also (mainly) differences when dealing with vision and point of view : we will particularly study the occurrences of LOOK, SEE, and SEEM, and BE+V-ING in both works, and we will try to show their importance in terms of narrative strategy. They are of prime importance in Susan Glaspell’s painting of her society