1,187 research outputs found
Water Footprint, Blue Water Scarcity, and Economic Water Productivity of Irrigated Crops in Peshawar Basin, Pakistan
Get PDFPakistan possesses the fourth largest irrigation network in the world, serving 20.2 million hectares of cultivated land. With an increasing irrigated area, Pakistan is short of freshwater resources and faces severe water scarcity and food security challenges. This is the first comprehensive study on the water footprint (WF) of crop production in Peshawar Basin. WF is defined as the volume of freshwater required to produce goods and services. In this study, we assessed the blue and green water footprints (WFs) and annual blue and green water consumption of major crops (maize, rice, tobacco, wheat, barley, sugarcane, and sugar beet) in Peshawar Basin, Pakistan. The Global Water Footprint Assessment Standard (GWFAS) and AquaCrop model were used to model the daily WF of each crop from 1986 to 2015. In addition, the blue water scarcity, in the context of available surface water, and economic water productivity (EWP) of these crops were assessed. The 30 year average blue and green WFs of major crops revealed that maize had the highest blue and green WFs (7077 and 2744 m3/ton, respectively) and sugarcane had the lowest blue and green WFs (174 and 45 m3/ton, respectively). The average annual consumption of blue water by major crops in the basin was 1.9 billion m3, where 67% was used for sugarcane and maize, covering 48% of the cropland. The average annual consumption of green water was 1.0 billion m3, where 68% was used for wheat and sugarcane, covering 67% of the cropland. The WFs of all crops exceeded the global average. The results showed that annually the basin is supplied with 30 billion m3 of freshwater. Annually, 3 billion m3 of freshwater leaves the basin unutilized. The average annual blue water consumption by major crops is 31% of the total available surface water (6 billion m3) in the basin. Tobacco and sugar beet had the highest blue and green EWP while wheat and maize had the lowest. The findings of this study can help the water management authorities in formulating a comprehensive policy for efficient utilization of available water resources in Peshawar Basin
Correction to: The ‘can do, do do’ concept in COPD; quadrant interpretation, affiliation and tracking longitudinal changes
No full textFollowing publication of the original article [1], the authors identified a mistake in the author names, as both forename and initials were stated. Initially published author names: A. J. Alex van ’t Hul, E. H. Noortje Koolen, H. W. Jeroen van Hees, B. Bram van den Borst and M. A. Martijn Spruit Correct author names: Alex J. van ‘t Hul, Noortje H. Koolen, Jeroen W. van Hees, Bram van den Borst, Martijn A. Spruit. The original article has been corrected.</p
Corrigendum: A Worm's World: Ecological Flexibility Pays off for Free-Living Nematodes in Sediments and Soils
No full textIn a recent article (doi:10.1093/biosci/biz086), the name of the second author was misspelled in the byline. It should have read Martijn Holterman. It is spelled correctly throughout the remainder of the manuscript.</p
Exercise training in diabetes
No full textType 2 diabetes mellitus (T2DM) is a growing epidemic
carrying an important risk of micro- and macrovascular
disease.1 Multiple studies have demonstrated that exercise training has a favourable effect on metabolic parameters, such as insulin sensitivity and lipid profile, and on
endothelial function.1,2 These metabolic parameters and
endothelial dysfunction are important for the development of coronary artery disease and stroke.3 Kemps
et al.4 reviewed the literature on the role of different
exercise modalities for different targets in cardiovascular
prevention in patients with T2DM (Figure 1).The author(s) received no financial support for the research, authorship, and/or publication of this article
Optimizing district heating networks: Exploring the solution space: Transporting geothermal energy to consumers in Delft
No full textSociety is facing a huge challenge in switching the energy sectors dependence on fossil fuels into an energy sector using mostly renewable energy sources. The switch towards using more sustainable energy sources is known as the energy transition. The goal of the energy transition is to lower the greenhouse gas (GHG) emissions emitted by the energy sector. Lowering the GHG emissions helps society limit the global warming caused by GHG [3]. 17.5 % of the global energy usage comes from the energy use in buildings [50]. It is thus very important that the energy use in buildings transitions towards using more sustainable energy sources. One of the renewable energy sources that is ought promising in the energy transition for energy use in buildings is geothermal energy [3]. Geothermal energy is energy that is captured in reservoirs of hot water in the earth’s crust. The hot water captured in the hot water pockets is pumped to the surface, to use it in spatial heating. The return pipe returns the cooled water to the geothermal well, where it can heat up again over a certain period of time [63] [23].In some cases, geothermal energy is applied using a district heating network. A district heating network is an example of a system that provides heating and/or cooling capacities to a group of buildings [65]. A district heating network is a network of pipelines that transport the hot water from the geothermal well to the buildings in the district. A geothermal well in combination with a district heating network is developed in Delft [27]. The district heating network will deliver energy to the TU Delft campus, two neighborhoods in Delft and industry at the Schieweg in Delft [28].Besides the district heating network in Delft, it is expected that district heating networks will be applied more often to accelerate the energy transition. Yun-Chao and Chen (2012) concluded that most optimization techniques optimize the whole system with its components. Less optimization techniques are applied to the sole components. Besides the fact that most optimization methods optimize the system as a whole, most optimization objectives only include optimizing the cost of the system. Also, effective optimization techniques are required as optimizing large graphs may be computationally time consuming [36]. In literature there are also clear signals that state that the trade-off between thermal comfort, and efficiency with respect to cost has to be tackled [53]. In this research, optimizing district heating networks for cost is compared to optimizing district heating to maximize thermal comfort or efficiency.In this research two models are developed: a model that calculates the cost of the district heating network, and a model that calculates the thermal losses of the district heating network. Both models are applied to a district heating networks that is developed in a street network. Furthermore, multiple heuristics are applied to come up with better district heating networks. The optimization technique is tested on 100 small, randomly generated district heating networks. After that, the district heating network in Delft is optimized. The differences in cost, efficiency, etc. will be evaluated. Besides, the performances of the district heating networks are evaluated by introducing energy deficits under different conditions.Optimizing the district heating networks for cost led to a very consistent result: When compared to their individual starting point, the district heating networks became cheaper and more efficient. A moderate-strong correlation is found between the the increase in efficiency and the decrease in cost while optimizing the district heating networks. In contrast to that, the networks that maximize efficiency are much more expensive than their cost optimized alternative, while the increase in efficiency is in most cases moderate. However, there are rare cases where the efficiency is increased much at a moderate increase in cost. This phenomenon is also found in Delft. Given the result that the efficient district heating network also performed much better than the cheapest alternative during energy deficits, in this research it is shown that choosing an objective function has a very large impact on the characteristics of the network. Therefore it is shown that for future district heating network optimization, it is important to trade off cost against efficiency.Complex Systems Engineering and Management (CoSEM
Outcome novelty in Exploratory Modellingand Analysis: A research into the value of novelty search for exploratory modelling
No full textNovelty search is a state-of-the-art approach focusing on behavioural novelty, rewarding diverging, as opposed to pursuing static objectives. This is relevant for exploratory modelling and analysis, which focuses on exploration of model through open exploration or directed search. Novelty search as an open exploration strategy is being tested against proven methods such as latin hypercube sampling. Using existing evolutionary algorithms and a developed novelty function, the experiments focus on comparisson, impact of the number of functional evaluations and the impact of the goals of the evolutionary algorithm. Finally it can be concluded that novelty search finds novelties in the lake problem, which makes it a relevant search strategy, but not suited for indiviual exploration. That means that it would still be advised to use latin hypercube sampling for earlier exploration.Engineering and Policy Analysi
Improving vario-scale implementation based on needs of Kadaster topographic data users
No full textVario-scale is a new mapping technique which automatically generalizes maps from a baselayer of faces. Applications of vario-scale are continuous, smooth zoom in web maps,multi-scale representation in one map and being able to generate maps at arbitrary scale. Also,this would only require having to maintain the dataset at the highest scale level, since all otherscales are derived from it.Potentially, vario-scale could be an alternative for current web maps and generalizationalgorithms. The Dutch national mapping agency, Kadaster, currently employs its owngeneralization process. However, they would like to know whether the users of theirtopographic datasets are interested in vario-scale. At this moment, there is a workingimplementation of vario scale (made by dr. ir. Martijn Meijers). This implementation,however, is still lacking in, for example, cartographic quality. Therefore the research questionin this project is: how can the implementation of vario-scale be improved to better meet theneeds for end users of Kadaster topographic data?This question is answered by questioning surveying users of Kadaster data on what theywould like to see improved about the existing implementation. Combining this with anexploration of the current software leads to an attempt at improving the currentimplementation. The project goal is set as enabling the road network visualization and mobilemap adaptation. Road network visualization is achieved by building the roads space scalecube and overlay with the background area at the front-end. Mobile map adaptation is realizedby creating the touch screen interaction between the device and the user. Finally, a validationsurvey is conducted to examine the difference between the original vario scaleimplementation and the adapted one.Synthesis Project 2018Geomatic
Hacking the city: making it more bikeable
No full textMartijn de Waal is a senior researcher at the lectorate of Play and Civic Media and a member of the Citizen Data Lab at the Amsterdam University of Applied Sciences. Het is the author of The City as Interface. How Digital Media Are Changing the City (2014), and the project leader of The Hackable City research project. He is also the co-founder of TheMobileCity.nl an international think tank that since 2007 addressed the relation between digital media and urbanism. His most recent book, co-authored with José van Dijck and Thomas Poell – only available in Dutch – is The Platform Society. The Struggle for Public Value in an Onlie World (2016)
Social policy and macroeconomics : the Irish experience
Get PDFThe remarkable performance of the Irish economy in recent years has attracted much attention. Within a 10-year period the economy went from an 18 percent unemployment rate to nearly full employment, while the ratio of debt to GDP fell from 120 percent to less than 50 percent. Inevitably, this success was also accompanied by problems, as infrastructure came under increasing stress, environmental difficulties became more evident, and a changing social structure resulted in some groups becoming increasingly marginalized. What worked and what did not? In particular, are there lessons that may be relevant for other countries facing similar difficulties, especially in Asia and Latin America? McCarthy focuses on three features of Ireland's economic achievements. Two of these features are external: the opening to Europe and the role of foreign direct investment. The third and perhaps most"exportable"feature is domestic: the role of a social pact. This pact was initially between employers, trade unions, and the government. Subsequent pacts were extended to include a variety of other groups. McCarthy discusses the far-reaching impact of this series of pacts on health, poverty, employment, education, and social welfare. Ireland now faces a number of challenges, including the slowdown in the global economy, a fall in resource transfers from the European Union, and the potential effects of the entry into the EU of Hungary and Poland.Economic Theory&Research,Environmental Economics&Policies,Public Health Promotion,Health Monitoring&Evaluation,Labor Policies,Economic Theory&Research,Environmental Economics&Policies,Health Monitoring&Evaluation,Poverty Assessment,National Governance
Determination and integration of appropriate spatial scales for river basin modelling
Get PDFAppropriate spatial scales of dominant variables are determined and integrated into an appropriate model scale. This is done in the context of the impact of climate change on flooding in the River Meuse in Western Europe. The objective is achieved by using observed elevation, soil type, land use type and daily precipitation data from several sources and employing different relationships between scales, variable statistics and outputs. The appropriate spatial scale of a key variable is assumed to be equal to a fraction of the spatial correlation length of that variable. This fraction was determined on the basis of relationships between statistics and scale and an accepted error in the estimation of the statistic of 10%. This procedure resulted in an appropriate spatial scale for precipitation of about 20 km in an earlier study. The application to river basin variables revealed appropriate spatial scales for elevation, soil and land use of respectively 0·1, 5·3 and 3·3 km. The appropriate model scale is determined by multiplying the appropriate variable scales with their associated weights. The weights are based on SCS curve number method relationships between the peak discharge and some specific parameters like slope and curve number. The values of these parameters are dependent on the scale of each key variable. The resulting appropriate model scale is about 10 km, implying 225-250 model cells in an appropriate model of the Meuse basin meant to assess the impact of climate change on river flooding. The usefulness of the appropriateness procedure is in its ability to assess the appropriate scales of the individual key variables before model construction and integrate them in a balanced way into an appropriate model scale. Another use of the procedure is that it provides a framework for decisions about the reduction or expansion of data networks and need
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