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Wageningen, Netherlands

Duan Z.,Technical University of Delft | Bastiaanssen W.G.M.,Technical University of Delft | Bastiaanssen W.G.M.,Competence Center
Remote Sensing of Environment | Year: 2013

Water levels in lakes and reservoirs can currently be obtained from four different satellite altimetry databases: (i) Global Reservoir and Lake Monitoring (GRLM), (ii) River Lake Hydrology (RLH), (iii) Hydroweb and (iv) ICESat-GLAS level 2 Global Land Surface Altimetry data (ICESat-GLAS). This paper proposes a new method for estimating water volume changes in lakes and reservoirs from these four databases in combination with satellite imagery data, without any in-situ measurements and bathymetry maps. Three lakes/reservoirs with different characteristics were studied, i.e. Lake Mead (U.S.A.), Lake Tana (Ethiopia) and Lake IJssel (The Netherlands). Compared to in-situ water levels, satellite altimetry products provided accurate water level variations for Lake Mead and Lake Tana but not for Lake IJssel. The long-term lowest water level in each satellite altimetry database was used as the reference level for water volume estimation. All water levels were converted to the Water Level Above the Lowest Level (WLALL), and the series of Landsat TM/ETM+imagery data were selected to extract corresponding surface areas for establishing area-WLALL relationships. Subsequently, the relationships of the Water Volume Above the Lowest water Level (WVALL) and WLALL were obtained through the analytical integration of area-WLALL relationships. The WVALL-WLALL relationships are site-specific and database-specific and can be used to convert water levels from the four databases directly into water volumes above the identified minimum levels for the same lake. Validation showed that estimated water volumes agreed well with in-situ measurements (R2 from 0.95 to 0.99) and the root mean square error (RMSE) was within 4.6 to 13.1% of the mean volumes of in-situ measurements. © 2013 Elsevier Inc. Source

Duan Z.,Technical University of Delft | Bastiaanssen W.G.M.,Technical University of Delft | Bastiaanssen W.G.M.,Competence Center
Remote Sensing of Environment | Year: 2013

Accurate precipitation data at high spatial and temporal resolution is deemed necessary for many hydrological and water management applications, and especially in data scarce river basins and regions where strong competition for water resources prevails. In this study we used a new downscaling-calibration procedure of the freely accessible Version 7 of TRMM (Tropical Rainfall Measuring Mission) 3B43 product, in conjunction with limited rain gauge data sets, to generate improved monthly pixel-based precipitation data at higher spatial resolution (1km). The spatial downscaling from 0.25° to 1km grids was achieved by using site-specific non-linear relationships between annual precipitation and annually averaged NDVI (Normalized Difference Vegetation Index). The calibration was based on Geograhical Difference Analysis (GDA) and Geographical Ratio Analysis (GRA). The new integrated procedure was tested for Lake Tana Basin (LTB) in Ethiopia with a humid climate (rainfall 1395 mm/yr during 1998-2004) and for the Caspian Sea Region (CSR) in Iran with a semi-arid climate (rainfall 442 mm/yr during 1999-2003). The best 1km annual precipitation data were achieved through downscaling followed by GDA calibration for most cases. The monthly fractions derived from the un-calibrated TRMM 3B43 product can be used to disaggregate 1km annual precipitation to 1km monthly precipitation. The disaggregated 1km monthly precipitation has not only significant improvement in the spatial resolution, but also good agreements with rain gauge data were achieved for both LTB (R2=0.87, RMSE=56mm, MAE=32mm and Bias=0.01) and the CSR (R2=0.79, RMSE=23mm, MAE=16mm and Bias=0.14). A similar calibration procedure using rain gauges at monthly time scale did not improve the level of performance. © 2012 Elsevier Inc. Source

Mellingen S.,Competence Center | Torsheim T.,University of Bergen | Thuen F.,Bergen University College
Journal of Studies on Alcohol and Drugs | Year: 2015

Objective: This study examined the relationship between marital status, family size, and postpartum alcohol use from birth to 36 months postpartum, based on data from the Norwegian Mother and Child Cohort Study. Method: Mothers’ self-reported alcohol frequency and alcohol units per drinking occasion at 0–3 months, 4–6 months, 18 months, and 36 months postpartum were modeled using linear mixed models for repeated measures. Results: There was a strong main effect of time on alcohol use, with increases in alcohol use from childbirth to 36 months after childbirth. Adjusting for covariates, there were threeway interaction effects for Time × Family Structure × Family Size for alcohol units and alcohol frequency, indicating that a change in alcohol use varied as a function of family structure and family size. Single mothers had a lower increase in frequency of alcohol use but a steeper increase in the number of alcohol units. However, this effect was less pronounced with increasing family size. Conclusions: The patterns of findings are consistent with a differential opportunity perspective on alcohol use. © 2015, Alcohol Research Documentation Inc. All rights reserved. Source

Zellweger J.-P.,Competence Center
Panminerva Medica | Year: 2013

Tuberculosis is a rare disease in Europe, so that most medical doctors never see a case and, although they know that the disease exists, they usually do not include it among the differential diagnosis of many respiratory or general disorders. Why is it, therefore, still important to speak about TB? This paper analysis some reasons: 1) TB is rare but has not disappeared. In Europe, some 400,000 cases are registered each year, with a slight decreasing tendency over the last few years but great disparities between countries and regions; 2) TB is more frequent in some risk groups, particularly among patients born in a country with a high incidence of disease or in persons exposed to the contact with TB, like close relatives of infectious patients. In EU/EEA, the majority of TB cases are observed among foreign-born persons; 3) if infected, some persons have a higher risk to develop TB. Small children and persons with viral or drug-induced immunosuppression (for instance anti-TNF) must be screened and protected if infected; 4) cases of TB among migrants generally occur after the entry in the country, from reactivation of latent TB acquired before. The border screening does not offer a garantee that the disease has been detected. Due attention to incurring symptoms and easy access to care must be maintained during the whole stay in the country for all foreign-born persons; 5) one of the major threats for the future is the progressive increase in the number of cases resistant to first-line drugs (Multidrug-resistant TB or MDR-TB) in several regions of the world, particularly in Eastern Europe; 6) due to decreasing knowledge and experience with the diagnosis and management of TB, many cases are diagnosed at a late stage. Medical doctors are encouraged to share their questions with experts and refer to existing Guidelines. Source

« Ford offers Apple Siri Eyes-Free to millions of vehicles globally through SYNC update | Main | Hyundai Tucson Fuel Cell exceeds 94 mph in desert test » Kalmar, part of Cargotec, will introduce the first fast charging solution for electric powered shuttle and straddle carriers. The Kalmar FastCharge solution is locally emission free and can be applied to both automated and manual operation. The Kalmar FastCharge solution is based on the same opportunity charging technology that is used in electric buses. The charging station with a pantograph direct current charging system is located flexibly on the working route of the machines in the terminal. The machine has Lithium-ion (Li-ion) batteries which enable fast charging to be used. Charging occurs during the idle time in the machine working cycle when it has stopped to wait for the container. Typical charging time in operation is 30 to 180 seconds, and with the maximum charging power of 600 kW, full charge can be achieved in a few minutes. Customers have been asking for electric powered shuttle operation for a while already. This technology makes the charging process smooth, as there is no need to take the machine out of operation for battery swapping. Neither is there a need to invest in battery swapping stations and extra batteries. Our hybrid technology has been extremely well received by the market. We have long experience in Lithium-Ion technology in hybrid machines, and this development is a natural next step in reducing emissions. This latest complement to our portfolio will provide excellent value to terminals which are facing even tighter environmental requirements. The Kalmar FastCharge solution consists of electric powered shuttle or straddle carriers and fast charging stations. Kalmar continues to test and verify the solution at the Tampere Technology and Competence Center in Finland, with plans to bring the solution to the market during 2016.

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