551 research outputs found
Back Analysis of the Lower San Fernando Dam Slide Using a Multi-block Model
A multi-block sliding system model has been developed to simulate the displacement of sliding geo-masses. This model is a useful tool, especially when displacements are very large and computer codes based on the Finite Element Method cannot be applied. The paper investigates the ability of the model to predict the response of the well-documented Lower San Fernando Dam slide. The predicted movement, and deformation agreed reasonably well with that of the upper part of the slide. Yet, the lower part of the slide slid more that the model prediction. The multi-block model was applied a second time. This 2-slide approach predicts movement, and deformation in very good agreement with that measured. In addition, the time duration of motion is in general agreement with the observed
Stacking classifiers for anti-spam filtering of e-mail
We evaluate empirically a scheme for combining classifiers, known as stacked
generalization, in the context of anti-spam filtering, a novel cost-sensitive
application of text categorization. Unsolicited commercial e-mail, or "spam",
floods mailboxes, causing frustration, wasting bandwidth, and exposing minors
to unsuitable content. Using a public corpus, we show that stacking can improve
the efficiency of automatically induced anti-spam filters, and that such
filters can be used in real-life applications
Preloading for Large Storage Building
The properties and method of preloading a 11 m erratic deposit of soft clays and loose sands, are described. Under the preload embankment of 12 m the deposit compressed an average of 7%. Settlement developed rapidly and excess porepressure dissipated within few days, never exceeding 2.1 m of water head. After preload removal borings were performed to compare results with those obtained on the untreated site. This comparison showed that the compressibility and strength of both the clayey and sandy components improved substantially and that the subsurface became more homogeneous. The projected structure built on the improved ground has performed satisfactorily
Stability of an Erratic Tailings Deposit
150 million cubic meters of erratic colliery spoils were deposited between 1971 and 1983 close to the Kardia lignite fields, in Greece. The heap finally reached satisfactorily an escalating height of 73 m. Field reconnaissance, collation of local experience and geotechnical investigations were performed during midstage of deposition. They aimed at an optimal configuration of the fill in progress, within the possibilities allowed by extensive earth moving operations. Present paper out- 1ines the approach and the methodology used to arrive at strength parameters and slope design of a highly inhomogeneous massive comprising variegated soils, marls and encaptured lignites
Improvement of Dynamic Soil Properties Induced by Preloading Verified by a Field Test and Embankment Failure
The results of an elaborate field preloading study on a liquefaction-susceptible site are presented. Preloading was applied by a temporary embankment 9m high. Prior and after preloading, borings with standard penetration tests, cone penetration tests and geophysical studies were performed. During the process of embankment construction and demolition, settlements, excess pore pressures and vertical and horizontal stresses were recorded versus time at different locations. A partial embankment failure occurred during the preloading process. A method predicting failure during the construction of the preload embankment based on excess pore pressure measurements is proposed and verified
Management of multiple, late onset complications in a 33-year-old female, with a ventriculoperitoneal shunt and crohn\u27s disease
Numerous complications can occur after the placement of a venticuloperitoneal shunt. The late onset of an autoimmune disease such as Crohn\u27s disease can be the disruptive factor for a previously well functioning shunt. A 33-year-old female with a ventriculo-peritoneal shunt since the age of 7, as well as Crohn\u27s disease since the age of 25, presented in the ER with dysuria, long-lasting fever and intermittent severe headache. The patient underwent a CT scan of the chest, abdomen and brain. An enlargement of the ventricular system was revealed, suggesting malfunction of the shunt. Simultaneously, the abdominal scan revealed an abnormal course of the peritoneal catheter of the shunt in the lower abdomen, inside the bladder. The existence of the catheter inside the bladder was confirmed and filmed during a cystoscopy and was attributed to the several inflammations and surgeries performed for the treatment of Crohn\u27s disease.The absence of an obvious stenosis of the aqueduct, the early immunodeficiency due to Azathioprine and the multiple abdominal surgeries made the treatment selection a complex algorithm for the neurosurgeon
Geomorphological reconnaissance of the Psathopyrgos and Rion-Patras Fault zones (Achaia, NW Peloponnesus).
Στην εργασία αυτή συζητώνται γεωμορφολογικές παρατηρήσεις κατά μήκος των ενεργών ρηξιγενών ζωνών Ψαθοιτύργου και Ρίου-Πατρών (ΒΑ τμήμα). Οι ρηξιγενείς ζώνες αυτές αντιστοιχούν σε ρηξιγενή μέτωπα περισσότερο ή λιγότερο πολύπλοκης μορφολογίας. Τα γεωμορφολογικά χαρακτηριστικά των μετώπων δίδουν πληροφορίες για την γεωμετρία των ζωνών αυτών, συμπληρωματικές των ήδη υπαρχόντων δεδομένων από γεωλογικές έρευνες. Στοχεύοντας στην αναγνώριση θέσεων δυνητικά κατάλληλων για γεωμορφολογικές και γεωλογικές έρευνες για την εκτίμηση των ρυθμών ολίσθησης ρηγμάτων αυτών των ζωνών κατά το Ολόκαινο, περιγράφονται περιπτώσεις ρηγματωμένων ολοκαινικών γεωμορφών και σχετιζόμενων με αυτές επιφανειακών αποθέσεων. Επι πλέον, συζητώνται τα προβλήματα ανεύρεσης θέσεων κατάλληλων για γεωλογικές/γεωμορφολογικές έρευνες γαι τον χρονικό προσδιορισμό πρόσφατων σεισμικών διαρήξεων (παλαιοσεισμολογία), προβλήματα που οφείλονται τόσο σε ανθρώπινες επεμβάσεις, όσο και σε φυσικές γεωμορφολογικές διεργασίες.In this communication we discuss reconnaissance geomorphological observations along the active Psathopyrgos and Rion-Patras (NE part) fault zones. These fault zones correspond to more or less complex rangefronts, the geomorphic characteristics of which provide hints on the details of the fault zone geometries, adding to the existing geological data in the bibliography. Aiming at the identification of locations suitable or potentially suitable for geomorphological and geological studies for the determination of fault slip rates in the Holocene, we describe cases of faulted Holocene landforms and associated surficial deposits. We also discuss problems involved in finding locations suitable for geological (paleoseismological) studies for the determination of the timing of recent earthquake ruptures, problems due to both man-made and natural causes
Predicting Landslide Risk Combining Space Measurements and Geotechnical Modeling: Application at Kerasia Slide
The work developed and applied a methodology combining (a) space measurement of past displacement and (b) geotechnical modelling of displacement to predict and mitigate the risk of ground displacement cased by progressive slope instability. The area of study is in Kerasea village in Plastiras Lake Municipality. The problem under treatment is a creeping landslide in an inhabited area. Mitigation measures were analyzed
Predicting Ground Subsidence Induced by Pumping Combining Space Measurements and Geotechnical Modeling: Application in the Thessaly Region, Greece
Space technology is a new technology that provides cost-effective measurements of past displacement data. Based on these displacement measurements, within the framework of the European Space Agency’s GMES Terrafirma Project, an improved geotechnical design approach is proposed combining geotechnical modelling and space measurements to predict ground subsidence induced by the lowering of the water table. Then the proposed methodology is applied to predict future displacement at the Thessaly plain - Carla region, Greece due to excessive pumping
Pulse processing routines for neutron time-of-flight data
A pulse shape analysis framework is described, which was developed for
n_TOF-Phase3, the third phase in the operation of the n_TOF facility at CERN.
The most notable feature of this new framework is the adoption of generic pulse
shape analysis routines, characterized by a minimal number of explicit
assumptions about the nature of pulses. The aim of these routines is to be
applicable to a wide variety of detectors, thus facilitating the introduction
of the new detectors or types of detectors into the analysis framework. The
operational details of the routines are suited to the specific requirements of
particular detectors by adjusting the set of external input parameters. Pulse
recognition, baseline calculation and the pulse shape fitting procedure are
described. Special emphasis is put on their computational efficiency, since the
most basic implementations of these conceptually simple methods are often
computationally inefficient.Comment: 13 pages, 10 figures, 5 table
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