2,682 research outputs found
Future Prospects for Macro Rainwater Harvesting (RWH) Technique in North East Iraq
Countries in Middle East and North Africa (MENA region) are considered arid and semi-arid areas that are suffering from water scarcity. They are expected to have more water shortages problem due to climatic change. Iraq is located in the Middle East covering an area of 433,970 square kilometers populated by 31 million inhabitants.
One of the solutions suggested to overcome water scarcity is Rain Water Harvesting (RWH). In this study Macro rain-water harvesting technique had been tested for future rainfall data that were predicted by two emission scenarios of climatic change (A2 and B2) for the period 2020-2099 at Sulaimaniyah Governorate north east of Iraq.
Future volumes of total runoff that might be harvested for different conditions of maximum, average, and minimum future rainfall seasons under both scenarios (A2 and B2) were calculated.
The results indicate that the volumes of average harvested runoff will be reduced when average rainfall seasons are considered due to the effect of climatic change on future rainfall. The reduction reached 10.82 % and 43.0% when scenarios A2 and B2 are considered respectively
Morphology of Tigris River within Baghdad City
In recent years, substantial changes have occurred in the morphology of the River Tigris within Baghdad City. Although huge volumes of sediment are being trapped in recently constructed headwater reservoirs, the number of islands in the Tigris at Baghdad is increasing. The debris of bridges destroyed in the wars of 1991 and 2003 and their subsequent reconstruction have enhanced the development of these islands. As a consequence the ability of the river to carry the peaks of flood waters has been reduced. This has led to potential increase of flooding in parts of the city. <br><br> The bed of the River Tigris has been surveyed on three occasions (1976, 1991, and 2008). The most recent survey was conducted by the Ministry of Water Resources, extended 49 km from the Al-Muthana Bridge north Baghdad to the confluence with the Diyala River south Baghdad. It yielded cross-section profiles at 250 m intervals. The data are used to predict the maximum flood capacity for the river using the one-dimensional hydraulic model for steady flow "HEC-RAS" modeling. Calibration of the model was carried out using field measurements for water levels along the last 15 km of the reach and the last 10 yr of observation at the Sarai Baghdad gauging station. <br><br> The model showed a significant predicted reduction in the current river capacity below that which the river had carried during the floods of 1971 and 1988. The three surveys conducted on the same reach of the Tigris indicated that the ability of the river to transport water has decreased
CLIMATE CHANGE AND FUTURE PRECIPITATION IN AN ARID ENVIRONMENT OF THE MIDDLE EAST: CASE STUDY OF IRAQ
In this paper impact of climate change on precipitation in the arid environment of Iraq is examined. LARS-WG weather generator was applied to 5 representative regions to model current and future precipitation under climate change. Seven Global Climate Models (GCMs) have been employed to account for any uncertainty on future projection for three selected periods, 2011-2030, 2046-2065 and 2080-2099. Performance of LARS-WG in each site was first evaluated using the Kolmogorov-Smirnov statistical test for fitting wet/dry days in each site, as well as comparison of the mean and standard deviation between the observed and simulated precipitation. The developed LARS-WG models were found to perform well and skilful in simulating precipitation in the arid regions of Iraq as evidenced by the tests carried and the comparison made. The precipitation models were then used to obtain future projections for precipitation using the IPCC scenario SRES A2. Future precipitation results show that most of the Iraq regions are projected to suffer a reduction in annual mean precipitation, especially by the end of the 21st century, while on a seasonal basis most of the regions are anticipated to be wetter in autumn and winter. Journa
Expected Future Precipitation in Central Iraq Using LARS-WG Stochastic Weather Generator
The Middle East (ME) is characterized by its water shortage problem. This region with its arid climate is expected to be the most vulnerable in the world to the potential impacts of climate change. Iraq (located in ME) is seriously experiencing water shortage problem. To overcome this problem rain water harvesting can be used. In this study the applicability of the long-term weather generator model in downscaling daily precipitation Central Iraq is used to project future changes of precipitation based on scenario of seven General Circulation Models (GCMs) outputs for the periods of 2011-2030, 2046-2065, and 2080-2099. The results indicated that December-February and September-November periods, based on the ensemble mean of seven GCMs, showed an increasing trend in the periods considered; however, a decreasing trend can be found in March, April, and May in the future
Climate Change and Future Long Term Trends of Rainfall at North-eastern Part of Iraq
Iraq is facing water shortage problem despite the presence of the Tigris and Euphrates Rivers. In this research, long rainfall trends up to the year 2099 were studied in Sulaimani city northeast Iraq to give an idea about future prospects. The medium high (A2) and medium low B2 scenarios have been used for purpose of this study as they are more likely than others scenarios, that beside the fact that no climate modeling canter has performed GCM (global climate model) simulations for more than a few emissions scenarios (HadCM3 has only these two scenarios) otherwise pattern scaling can be used for generating different scenarios which entail a huge uncertainty. The results indicate that the average annual rainfall shows a significant downward trend for both A2 and B2 scenarios. In addition, winter projects increase/decrease in the daily rainfall statistics of wet days, the spring season show very slight drop and no change for both scenarios. However, both summer and autumn shows a significant reduction in maximum rainfall value especially in 2080s while the other statistics remain nearly the same. The extremes events are to decrease slightly in 2080s with highest decrease associated with A2 scenario. This is due to the fact that rainfall under scenario A2 is more significant than under scenario B2. The return period of a certain rainfall will increase in the future when a present storm of 20 year could occur once every 43 year in the 2080s. An increase in the frequency of extreme rainfall depends on several factors such as the return period, season of the year, the period considered as well as the emission scenario used
LEE: A photorealistic virtual environment for assessing driver-vehicle interactions in self-driving mode
Photorealistic virtual environments are crucial for developing and testing automated driving systems in a safe way during trials. As commercially available simulators are expensive and bulky, this paper presents a low-cost, extendable, and easy-to-use (LEE) virtual environment with the aim to highlight its utility for level 3 driving automation. In particular, an experiment is performed using the presented simulator to explore the influence of different variables regarding control transfer of the car after the system was driving autonomously in a highway scenario. The results show that the speed of the car at the time when the system needs to transfer the control to the human driver is critical
The CCFM Monte Carlo generator CASCADE 2.2.0
CASCADE is a full hadron level Monte Carlo event generator for ep, \gamma p
and p\bar{p} and pp processes, which uses the CCFM evolution equation for the
initial state cascade in a backward evolution approach supplemented with off -
shell matrix elements for the hard scattering. A detailed program description
is given, with emphasis on parameters the user wants to change and variables
which completely specify the generated events
Ticagrelor Added to Aspirin in Acute Nonsevere Ischemic Stroke or Transient Ischemic Attack of Atherosclerotic Origin
Background and Purpose: Among patients with a transient ischemic attack or minor ischemic strokes, those with ipsilateral atherosclerotic stenosis of cervicocranial vasculature have the highest risk of recurrent vascular events. Methods: In the double-blind THALES (The Acute Stroke or Transient Ischemic Attack Treated With Ticagrelor and ASA for Prevention of Stroke and Death) trial, we randomized patients with a noncardioembolic, nonsevere ischemic stroke, or high-risk transient ischemic attack to ticagrelor (180 mg loading dose on day 1 followed by 90 mg twice daily for days 2-30) or placebo added to aspirin (300-325 mg on day 1 followed by 75-100 mg daily for days 2-30) within 24 hours of symptom onset. The present paper reports a prespecified analysis in patients with and without ipsilateral, potentially causal atherosclerotic stenosis ≥30% of cervicocranial vasculature. The primary end point was time to the occurrence of stroke or death within 30 days. Results: Of 11 016 randomized patients, 2351 (21.3%) patients had an ipsilateral atherosclerotic stenosis. After 30 days, a primary end point occurred in 92/1136 (8.1%) patients with ipsilateral stenosis randomized to ticagrelor and in 132/1215 (10.9%) randomized to placebo (hazard ratio 0.73 [95% CI, 0.56-0.96], P=0.023) resulting in a number needed to treat of 34 (95% CI, 19-171). In patients without ipsilateral stenosis, the corresponding event rate was 211/4387 (4.8%) and 230/4278 (5.4%), respectively (hazard ratio, 0.89 [95% CI, 0.74-1.08]; P=0.23, Pinteraction=0.245). Severe bleeding occurred in 4 (0.4%) and 3 (0.2%) patients with ipsilateral atherosclerotic stenosis on ticagrelor and on placebo, respectively (P=NS), and in 24 (0.5%) and 4 (0.1%), respectively, in 8665 patients without ipsilateral stenosis (hazard ratio=5.87 [95% CI, 2.04-16.9], P=0.001). Conclusions: In this exploratory analysis comparing ticagrelor added to aspirin to aspirin alone, we found no treatment by ipsilateral atherosclerosis stenosis subgroup interaction but did identify a higher absolute risk and a greater absolute risk reduction of stroke or death at 30 days in patients with ipsilateral atherosclerosis stenosis than in those without. In this easily identified population, ticagrelor added to aspirin provided a clinically meaningful benefit with a number needed to treat of 34 (95% CI, 19-171). Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT03354429
First encounters in the north : cultural diversity and gene flow in Early Mesolithic Scandinavia
Population genetic studies often overlook the evidence for variability and change in past material culture. Here, the authors use a Mesolithic example to demonstrate the importance of integrating archaeological evidence into the interpretation of the Scandinavian hunter-gatherer genetic group. Genetic studies conclude that this group resulted from two singleevent dispersals into Scandinavia before 7500 BC. Archaeological evidence, however, shows at least six immigration events pre-dating the earliest DNA, and that the first incoming groups arrived in Scandinavia before 9000 BC. The findings underline the importance of conducting careful archaeological analysis of prehistoric human dispersal in tandem with the study of ancient population genomics.Population genetic studies often overlook the evidence for variability and change in past material culture. Here, the authors use a Mesolithic example to demonstrate the importance of integrating archaeological evidence into the interpretation of the Scandinavian hunter-gatherer genetic group. Genetic studies conclude that this group resulted from two single-event dispersals into Scandinavia before 7500 BC. Archaeological evidence, however, shows at least six immigration events pre-dating the earliest DNA, and that the first incoming groups arrived in Scandinavia before 9000 BC. The findings underline the importance of conducting careful archaeological analysis of prehistoric human dispersal in tandem with the study of ancient population genomics.Peer reviewe
Control of triceps surae stimulation based on shank orientation using a uniaxial gyroscope during gait
This article presents a stimulation control method using a uniaxial gyroscope measuring angular velocity of the shank in the sagittal plane, to control functional electrical stimulation of the triceps surae to improve push-off of stroke subjects during gait. The algorithm is triggered during each swing phase of gait when the angular velocity of the shank is relatively high. Subsequently, the start of the stance phase is detected by a change of sign of the gyroscope signal at approximately the same time as heel strike. Stimulation is triggered when the shank angle reaches a preset value since the beginning of stance. The change of angle is determined by integrating angular velocity from the moment of change of sign. The results show that the real-time reliability of stimulation control was at least 95% for four of the five stroke subjects tested, two of which were 100% reliable. For the remaining subject, the reliability was increased from 50% found during the experiment, to 99% during offline processing. Our conclusion is that a uniaxial gyroscope on the shank is a simple, more reliable alternative to the heel switch for the purpose of restoring push-off of stroke subjects during gait
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