Probabilistic Perspectives on Collecting Human Uncertainty in Predictive Data Mining

In many areas of data mining, data is collected from humans beings. In this contribution, we ask the question of how people actually respond to ordinal scales. The main problem observed is that users tend to be volatile in their choices, i.e. complex cognitions do not always lead to the same decisions, but to distributions of possible decision outputs. This human uncertainty may sometimes have quite an impact on common data mining approaches and thus, the question of effective modelling this so called human uncertainty emerges naturally. Our contribution introduces two different approaches for modelling the human uncertainty of user responses. In doing so, we develop techniques in order to measure this uncertainty at the level of user inputs as well as the level of user cognition. With support of comprehensive user experiments and large-scale simulations, we systematically compare both methodologies along with their implications for personalisation approaches. Our findings demonstrate that significant amounts of users do submit something completely different (action) than they really have in mind (cognition). Moreover, we demonstrate that statistically sound evidence with respect to algorithm assessment becomes quite hard to realise, especially when explicit rankings shall be built

On a novel optimisation model and solution method for tactical railway maintenance planning

Within the ACEM-Rail project of the European Seventh Framework Programme new measurement and inspection techniques for monitoring the track condition are developed. By means of these new techniques the prediction of future track condition will be highly improved. To our knowledge mid-term maintenance planning is done for projects and preventive tasks, but predictions of the track condition are not incorporated into the planning process up to now. To efficiently utilise this new kind of information one task within the ACEM-Rail project is the development of methods for planning predictive maintenance tasks along with preventive and corrective ones in a mid-term planning horizon. The scope of the mid-term or tactical maintenance planning is the selection and combination of tasks and the allocation of tasks to time intervals where they will be executed. Thereby a coarse maintenance plan is determined that defines which tasks are combined together to form greater tasks as well as the time intervals for executing the selected tasks. This tactical plan serves as the base for booking future track possessions and for scheduling the maintenance tasks in detail. In this paper an algorithmic approach is presented which is able to react on dynamic and uncertain changes due to any track prediction updating. To this end optimisation algorithms are implemented within a rolling planning process, so it is possible to respond to updated information on track condition by adapting the tactical plan. A novel optimisation method is developed to generate cost effective and robust solutions by looking ahead into the future and evaluating different solutions in several scenario

VARIAZIONI NEL FLUSSO DI CO2 OSSERVATE NEL MARZO-APRILE 2009 IN ITALIA CENTRALE

In tutto il mondo nelle aree di collisione tettonica è stata osservata la presenza di sorgenti di acque calde o di gas di origine endogena (Italiano et al., 2001 e riferimenti citati). Il gas emesso più importante sotto il profilo quantitativo è l’anidride carbonica il cui ruolo è stato spesso sottolineato per giustificare la generazione di anomalìe di carattere geochimico osservate nelle acque sotterranee o nelle emissioni gassose. Nell’Italia centro-meridionale esistono numerose emissioni spontanee di anidride carbonica note come mofete o mefite. Nel corso della sequenza sismica del 1997 verificatasi in Umbria-Marche sono state monitorate le caratteristiche fisiche e composizionali di alcune emissioni di CO2 presenti nel territorio interessato dai principali eventi di carattere tettonico (Martinelli e Albarello, 1997). In particolare nel corso del 1997 sono state osservate variazioni di flusso di gas totale nelle emissioni di Monte Castello di Vibio, Umbertide e Massa Martana. Nelle stesse aree sono state osservate variazioni significative di carattere composizionale in grado di confermare la non stazionarietà dell’origine dei gas emessi (Italiano et al., 2004; Italiano et al., 2009 e bibliografia citata). Nel Comune di Massa Martana è localizzata l’emissione spontanea di anidride carbonica di San Faustino. L’emissione principale è captata da una opera di presa composta da una stanza sotterranea e da un insieme di tubi che convogliano il gas verso l’esterno. Alla fine del percorso di tubi è stata installata una strumentazione in grado di misurare la portata del gas. Il sensore è del tipo a “filo caldo”. Altri parametri di carattere ambientale sono monitorati nel sito e nella zona. Nel periodo 2005-2008 sono state osservate variazioni nei valori di portata del gas emesso in parte probabilmente ascrivibili alla attività tettonica della zona. Nel corso del 2009 sono stati affrontati e risolti problemi tecnici di alimentazione elettrica, ripristinata nel corso del mese di marzo. Alla fine del mese di Marzo 2009 e nel mese di aprile 2009 i valori di portata registrati sono stati pari a circa il doppio della normalità. I valori di portata sono poi ridiscesi entro la normalità entro un mese dalla data dell’evento principale della sequenza sismica del 2009 che ha interessato vaste aree dell’Abruzzo. La distanza tra il sito di osservazione e l’area epicentrale dell’evento principale della sequenza simica dell’aprile 2009 è di circa 80 km. Nella letteratura scientifica sono state riportateanomalìe di carattere geofisico e geochimico rilevate a distanze paragonabili a quelle descritte in concomitanza con eventi simici significativi. Fenomeni di possibile degassamento terrestre sono stati rilevati in quasi contemporaneità da altre unità di ricerca in grado di monitorare fenomenologie di area vasta con l’ausilio di tecniche satellitari (Aliano et al., 2009; Tramutoli et al., 2009). Il fenomeno osservato è iniziato alcuni giorni prima dell’evento sismico (Mw=6.3) del 6 aprile 2009 e può essere, in principio, interpretato come esito di processi di deformazione crostale osservati da altre unità di ricerca (e.g. Caporali, 2009). La composizione chimica di gas campionati nell’area epicentrale indica l’esistenza di fenomeni di fratturazione profonda e di liberazione di anidride carbonica di origine non superficiale (Bonfanti et al., 2009 e bibliografia citata, Italiano et al., 2009). La generazione e liberazione di gas di origine profonda è, in principio, in grado di confermare l’esistenza di possibili ulteriori anomalìe osservate nei fluidi della zona (e.g. Plastino et al., 2009). Il fenomeno osservato potrebbe essere interpretato come un fenomeno precursore dell’evento principale registrato e analizzato a posteriori. La possibile applicabilità del fenomeno osservato come strumento utile per migliorare le valutazioni di hazard è discussa e commentata

Job order assignment at optimal costs in railway maintenance

Tamping is an important part of railway maintenance. Well tamped ballast reduces track irregularities and increases travel safety and comfort. But if the ballast is in a bad condition, the train speed must be restricted, which leads to delays and penalty costs for the operator. In this paper a novel model for the tamping scheduling problem in a short-term planning horizon is presented. In contrast to other railway maintenance scheduling problems the penalty costs caused by deferring tamping activities are considered in the scheduling process beside the travel costs. Three greedy heuristics are presented and compared in different benchmarks. An outlook discusses issues of interest for further research

Einstein-aether theory, violation of Lorentz invariance, and metric-affine gravity

We show that the Einstein-aether theory of Jacobson and Mattingly (J&M) can be understood in the framework of the metric-affine (gauge theory of) gravity (MAG). We achieve this by relating the aether vector field of J&M to certain post-Riemannian nonmetricity pieces contained in an independent linear connection of spacetime. Then, for the aether, a corresponding geometrical curvature-square Lagrangian with a massive piece can be formulated straightforwardly. We find an exact spherically symmetric solution of our model.Comment: Revtex4, 38 pages, 1 figur

Anomalous fluid emission of a deep borehole in a seismically active area of Northern Apennines (Italy)

The Miano borehole, 1047 m deep, is located close to the river Parma in the Northern Apennines, Italy. A measuring station has been installed to observe the discharge of fluids continuously since November 2004. The upwelling fluid of this artesian well is a mixture of thermal water and CH4 as main components. In non-seismogenic areas, a relatively constant fluid emission would be expected, perhaps overlaid with long term variations from that kind of deep reservoir over time. However, the continuous record of the fluid emission, in particular the water discharge, the gas flow rate and the water temperature, show periods of stable values interrupted by anomalous periods of fluctuations in the recorded parameters. The anomalous variations of these parameters are of low amplitude in comparison to the total values but significant in their long-term trend. Meteorological effects due to rain and barometric pressure were not detected in recorded data probably due to reservoir depth and relatively high reservoir overpressure. Influences due to the ambient temperature after the discharge were evaluated by statistical analysis. Our results suggest that recorded changes in fluid emission parameters can be interpreted as a mixing process of different fluid components at depth by variations in pore pressure as a result of seismogenic stress variation. Local seismicity was analyzed in comparison to the fluid physico-chemical data. The analysis supports the idea that an influence on fluid transport conditions due to geodynamic processes exists. Water temperature data show frequent anomalies probably connected with possible precursory phenomena of local seismic events

The Einstein 3-form G_a and its equivalent 1-form L_a in Riemann-Cartan space

The definition of the Einstein 3-form G_a is motivated by means of the contracted 2nd Bianchi identity. This definition involves at first the complete curvature 2-form. The 1-form L_a is defined via G_a = L^b \wedge #(o_b \wedge o_a). Here # denotes the Hodge-star, o_a the coframe, and \wedge the exterior product. The L_a is equivalent to the Einstein 3-form and represents a certain contraction of the curvature 2-form. A variational formula of Salgado on quadratic invariants of the L_a 1-form is discussed, generalized, and put into proper perspective.Comment: LaTeX, 13 Pages. To appear in Gen. Rel. Gra

Job order assignment at optimal costs in railway maintenance

Tamping is an important part of railway maintenance. Well tamped ballast reduces track irregularities and increases travel safety and comfort. But if the ballast is in a bad condition, the train speed must be restricted, which leads to delays and penalty costs for the operator. In this paper a novel model for the tamping scheduling problem in a short-term planning horizon is presented. In contrast to other railway maintenance scheduling problems the penalty costs caused by deferring tamping activities are considered in the scheduling process beside the travel costs. Three greedy heuristics are presented and compared in different benchmarks. An outlook discusses issues of interest for further research

Anomalous fluid emission of a deep borehole in a seismically active area of Northern Apennines (Italy)

The Miano borehole of 1047 m depth is located close to the river Parma in the Northern Apennines, Italy. A measuring station is installed to observe the discharge of fluids continuously since November 2004. The upwelling fluid of this artesian well is a mixture of thermal water and methane as main components. In non-seismogenic areas, we would expect a relative constant fluid emission perhaps overlaid with long term variations from that kind of deep reservoirs during the time. However, the continuously record of the fluid emission, in particular the water discharge, the gas flow rate and the water temperature, show periods of stable values interrupted by anomalous periods of fluctuations in the recorded parameters. The anomalous variations of these parameters are of low amplitude in comparison to the total values but significant in their long-term trend. Meteorological influences of rain and barometric pressure were not detected in recorded data probably due to reservoir depth and relatively high reservoir overpressure. Influences due to the ambient temperature after the discharge were evaluated by statistical analysis. We consider that recorded changes in fluid emission parameters can be interpreted as a mixing process of different fluid components in depth by variations in pore pressure as result of seismogenic stress variation. Local seismicity was analyzed in comparison to fluid’s physico-chemical data. The analysis supports the idea of an influence to fluid transport conditions due to geodynamic processes exist. Water temperature data show frequent anomalies probably connected with possible precursory phenomena of local seismic events

Evidence of tectonic control on active arc volcanism: the Panarea-Stromboli tectonic link inferred by submarine hydrothermal vents monitoring (Aeolian arc, Italy)

The combination of the latest geophysical instruments and geochemical methods applied to the arc volcanism (Aeolian islands, Italy) has given new insights on the role of active tectonics on fluids migration. A continuous monitoring of the hydrothermal system off the island of Panarea has shown contemporaneous modifications of the vented fluids and the seismic activity of the nearby Stromboli volcano. The almost contemporary start of the last volcanic crisis at Panarea and Stromboli in 2002, besides the contemporary variation of the 3He/4He ratios at both the islands and the large number of submarine crater-shaped structures at Panarea, bears testimony to interconnections between the volcanic edifices. To confirm a tectonic drive of magmatic fluids over volcanic arcs implies that episodes of volcanic unrest can be triggered by the tectonic activity increasing the volcanic risk for the whole area, and this might be the case of the Stromboli-Panarea volcanic comple