Search results for "fall"

Assessment of soil particle erodibility and sediment trapping using check dams in small semi-arid catchments

2017

Check dams can be used as a source of information for studies on sediment characteristics and soil particle erodibility. In this study, sediment yield and grain size distribution (GSD) were measured in twenty small catchments draining into a rock check dam in NW Iran for different runoffs during 2010–2011. Significant correlations were found between sediment yield and slope steepness, vegetation cover and soil erodibility factor (K) of the catchments. The erodibility of soil particles was determined using the comparison of GSD between sediment and original soil. Clay was the most erodible soil particle which showed 2.05 times more percentage in sediment than the original soil. The erodibili…

REGIONAL FREQUENCY ANALYSIS FOR EXTREME RAINFALL IN SICILY

2008

AN INTEGRATED SYSTEM FOR THE ANALYSIS OF RAINFALL-TRIGGERED LANDSLIDES

2011

La presente ricerca mira a fornire un sistema integrato per l'analisi delle frane attivate da precipitazioni, sviluppando due diverse metodologie: un'analisi statica per l'individuazione delle zone maggiormente propense a produrre scivolamenti (susceptibility mapping) su scala spaziale regionale, ed un'analisi dinamica per la prevision del dove e quando un evento franoso potrebbe veri carsi, ad una scala spaziale di maggior dettaglio . L'analisi statica comporta lo sviluppo di modelli statistici in grado di stimare la probabilità di eventi franosi, sulla base della correlazione tra fattori predisponenti le frane e gli eventi storici. L'esito dell'analisi è la derivazione di una mappa suscet…

Ventricular paired pacing to control intractable junctional tachycardia following open heart surgery in a child.

1989

A 5-month-old girl presented postoperatively with an atrioventricular (A-V) junctional tachycardia at a rate of 245/min following surgical repair of tetralogy of Fallot. The systolic blood pressure dropped to 60 mmHg with this rapid heart rate, and the infant became shocked. Drugs and overdrive pacing were ineffective in suppressing the A-V junctional tachycardia and in improving cardiac output. Ventricular paired pacing was used successfully to halve the mechanically effective ventricular rate and to restore cardiac output. When ventricular paired pacing was stopped after 12 h, the spontaneous rhythm was an atrial rhythm with 1-1 A-V conduction. The patient was discharged in sinus rhythm o…

Diagnosis and predictability of intraseasonal characteristics of wet and dry spells over equatorial east Africa

2010

Most of Eastern Africa has arid and semi-arid climate with high space-time variability in rainfall. The droughts are very common in this region, and often persist for several years, preceded or followed by extreme floods. Most of the livelihoods and socio-economic activities however remain rain-dependent leading to severe negative impacts during the periods of occurrence of climate extremes. It has been noted that one extreme event was capable of reversing national economic growth made over a period of several years. Thus no sustainable development can be attained in eastern Africa without effective mainstreaming of climate information in the development policies, plans and programmes. Many…

Local Expected Shortfall-Hedging

2001

This paper proposes a self-financing trading strategy that minimizes the expected shortfall locally when hedging a European contingent claim. A positive shortfall occurs if the hedger is not willing to follow a perfect hedging or a superhedging strategy. In contrast to the classical variance criterion, the expected shortfall criterion depends only on undesirable outcomes where the terminal value of the written option exceeds the terminal value of the hedge portfolio. Searching a strategy which minimizes the expected shortfall is equivalent to the iterative solution of linear programs whose number increases exponentially with respect to the number of trading dates. Therefore, we partition th…

Drug-related falls and thraumatic brain injury in very old patients: antithrombotic drugs as new potential culpruit factors

2022

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Water flow paths in soil control element exports in an Andean tropical montane forest

2008

We tested the hypothesis that concentrations of chemical constituents in stream water can be explained by the depth of water flow through soil. Therefore, we measured the concentrations of total organic carbon (TOC), NO 3 -N, NH 4 -N, dissolved organic nitrogen (DON), P, S, K, Ca, Mg, Na, Al and Mn in rainfall, throughfall, stemflow, litter leachate, mineral soil solution and stream water of three 8-13 ha catchments on steep slopes (1900-2200 m above sea level) of the south Ecuadorian Andes, from April 1998 to April 2003. Peak C (14-22 mg litre -1 ), N (0.6-0.9 mg litre -1 ), K (0.5-0.7 mg litre -1 ), Ca (0.6-1.0 mg litre -1 ), Mg (0.3-0.5 mg litre -1 ), Al (110-390 μg litre -1 ) and Mn (3.…

The influence of ENSO on winter rainfall in South Africa

2011

Whereas the impact of ENSO on the African summer rainfall regions is largely documented and still regularly investigated, little is known about its impact on the winter rainfall regions located at the southwestern and northwestern tips of Africa. Yet, these regions are densely inhabited and are net exporters of high-quality agricultural products. Here we analyze the relationship between El Nino Southern Oscillation (ENSO) and South Africa austral winter rainfall using a 682 raingauges daily rainfall database documenting the period 1950–1999. The May, June and July (MJJ) seasonal rainfall amount shows a positive correlation with the Nino3.4 index that becomes significant since the so-called …

Delivery Truck Drivers’ Work Outside Their Cabs: Ergonomic Video Analyses Supplemented with National Accident Statistics

2014

Delivery truck drivers' work contains various physically and psychosocially demanding work situations. Fifteen drivers' and 8 other stakeholders' identifications of such work situations were examined by video analyses in this study. The identifications were analyzed in-depth by the researchers and compared with statistics on 3,507 accidents in the Finnish trucking industry. The aim was to determine what kind of identifications were made and to what degree the identifications coincided among the participants and with the accident statistics. The drivers' identifications differed from the statistics data. The statistics showed a significantly higher relative frequency of movement-related situ…