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Runoff simulation in highly anthropized catchments is complex, but essential for water management, especially in poorly gauged and data-scarce hydrosystems of the West African Sahel. This study aims to evaluate the effect of different calibration schemes on runoff simulation. The physically-based and semi-distributed hydrological SWAT (Soil and Water Assessment Tool) model is used to simulate daily runoff in the Nakanbé catchment at Wayen station in Burkina Faso (in the West African Sahel) over the period 2006–2012. Four (4) hydrometric stations (Dombré, Rambo, Ramsa and Wayen) gauging 4 nested catchments (ranging from 1060 to 21 178 km 2 in size) are considered. The added value of the consideration of nested catchments is assessed through the following 3 calibration schemes: one-site (OS) at the entire catchment outlet (Wayen); multi-sites with nested sub-catchments (MS1); and multi-sites without considering nested sub-catchments (MS2). The results indicate that OS and MS2 schemes perform well (KGE > 0.7, | PBIAS |<3 %), with MS2 scheme being superior (KGE, PBIAS). However, the MS1 scheme (KGE = 0.68; PBIAS = -22.9 %) performed worse in comparison to the traditional OS scheme. The comparison of the three modelling schemes provides evidence that accounting for nested sub-catchments does not necessarily improve the quality of rainfall-runoff simulations. Yet, multi-site calibration should be favoured when catchments are not nested. [ABSTRACT FROM AUTHOR]

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Two field Trials were conducted during the 2010 and 2011 cropping seasons at the Teaching and Research Farm of the Institute for Agricultural Research, Ahmadu Bello University Zaria located on latitude 11° 11'N, longitude 7 ° 38'E and 686m above sea level in Northern Guinea Savannah ecological zone of Nigeria to study the effect of different organic manures on the growth and yield of water melon (Citrullus lanatus L.). The experiment was laid out in a randomized complete block design replicated four times. The experiment consisted of five treatments namely; control, sawdust, goat manure, cow dung manure and poultry manure. The result indicated that there was a significant difference (P = 0.05) among the mean values on growth characters such as vine length, number of leaves per plant and number of branches per plant in both cropping seasons. Similarly, there was a significant difference ( P = 0.05) among the mean values on yield characters such as number of fruits per plant, fruit length per plant, fruit diameter per plant, and fruit yield per ha in the two cropping seasons. Poultry manure significantly produced higher mean values of all growth and yield characters, while the control treatment significantly produced lower mean values of all growth and yield characters in all the two cropping seasons. Increasing yield in watermelon production can be achieved by applying organic manure; therefore farmers wishing to embark in watermelon production are advised to use 1,684kg of poultry manure or any of these organic manure sources available at the rates used in this trial in order to increase their yield. [ABSTRACT FROM AUTHOR]

The IEEE 802.16 standard is one of the most promising broadband wireless access systems. The standard incorporates a QoS architecture that supports both realtime and non-realtime applications. To provide QoS three data schedulers are furnished by the architecture. However, the working of the schedulers are not defined by the standard. Some researchers have attempted to fill this gap by providing different scheduling schemes. However, no scheme has yet been adapted by the standard and the area is still open for new research. In this article we propose Two-Level Scheduling Algorithm (TLSA) that ensures QoS for all service classes, while avoiding starvation of lower priority classes. Furthermore, it ensures fair resource allocation among flows of the same class. The simulation results show that the algorithm is effective and efficient. [ABSTRACT FROM PUBLISHER]

The protection of pedestrians from injuries by accidental collision is a primary focus of the automotive industry and of government legislation [1]. In this area, scientists and developers are faced with a multitude of requirements. Complex scenes are to be analyzed. The wide spectrum of where pedestrians and cyclists appear on the road, weather, and light conditions are just examples. Data fusion of raw or preprocessed signals for several sensors (cameras, radar, lidar, ultrasonic) need to be considered as well. Accordingly, algorithms are very complex. When moving from prototypic environments to embedded systems, additional constraints must be considered. Limited system resources drive the need to simplify and optimize for technical and economic reasons. With all these constraints, how can the safety functions be safe-guarded? This submission considers scene-based methods for the development of vehicle functions from prototype to series production focusing on functional safety. Starting points are modeled use cases which can be evaluated by simulation and variation of internal parameters as well as external influences, like velocity, course, likelihoods, measurement errors and latencies. Based on these methods, the approach of scene based specifications is discussed. Scene based test catalogs are also considered. These test catalogs can consist of synthetic (simulated) test cases and recorded sequences. The effect of changes during a development project can be more reliably evaluated with stable and reproducible test cases. The article presents typical sample usage scenarios and discusses the results achieved so far. [ABSTRACT FROM PUBLISHER]