47 research outputs found
Contour Integrated Dual Band Compact Antenna Elements and Arrays for Low Profile Mobile Terminals
No full textNovel antenna element and array designs with very small space occupation for low-profile mobile applications are presented. The proposed antennas can be integrated at the contour of mobile devices. The antennas operate in two frequency bands around 2.4 and 5.5 GHz, corresponding to the common wireless local area network (WLAN) bands. By utilizing multiple resonance structures, the bandwidth in the lower frequency band reaches up to 200 MHz. Therefore, the long-term evolution (LTE) frequency band at 2.3 GHz is also supported. A two-element contour-integrated compact antenna array for multiple-input multiple-output (MIMO) communication systems with good MIMO performance is realized by implementing appropriate decoupling strategies. All proposed antennas are manufactured and measured. Compared to conventional design approaches, the proposed approach is advantageous in several respects, e.g., the radiation elements occupy much less space and its operation is independent from the shape of the chassis. The design approach is applicable for all ultra-thin devices with conducting contours
Electromagnetic Field Synthesis by Hierarchical Plane Wave-Based Field Transformation
No full textn optimization-based field synthesis approach is presented that employs a hierarchical plane wave-based field transformation concept for efficient evaluation of the inverse problem forward operator. Irregular transmit antenna array configurations can be used to synthesize a target field distribution in an arbitrarily shaped test volume with full consideration of the antenna element radiation characteristics. For this purpose, a triangular mesh forms the test zone boundary surface on which Rao–Wilton–Glisson (RWG) vector-basis functions perform electric and magnetic field testing. An iterative Krylov subspace solver is employed to solve the ill-posed inverse problem for the transmit antenna coefficients. The effectiveness, accuracy, and efficiency of the proposed field synthesis algorithm are demonstrated for configurations with test zone extents of up to one hundred wavelengths. Moreover, the approach is utilized for antenna measurements, where antenna near-fields are transformed into far-fields
Extending the Plane Wave Based Fast Irregular Antenna Field Transformation Algorithm for Amplitude-Only Data
No full textThe Most Famous Writer of the Low Countries: Herman Brusselmans Star Author and (Reluctant) Public Intellectual
Get PDFAbstractThe Flemish writer Herman Brusselmans is the most famous author of the Low Countries. In this article, Herman Brusselmans is analysed as a star author. First and foremost, two striking aspects of Brusselmans’s stardom are analysed: his public visibility and the cult of the private. Attention is then focused on Brusselmans’s experience of celebrity, which he - like many other star authors - thematises in his books. Doing so, he consciously places himself in the context of popular culture. On the other hand, as a result of his celebrity status he has been expected - particularly in the last few years - to assume the role of public intellectual willy-nilly, and this in turn has had consequences for his work.</jats:p
Designing Procedurally Generated Levels
No full textWe aim to improve on the design of procedurally generated game levels. We propose a method which empowers game designers to author and control level generators, by expressing gameplay-related design constraints. Following a survey conducted on recent procedural level generation methods, we argue that gameplay-based control is currently the most natural control mechanism available for generative methods. Our method uses graph grammars, the result of the designer-expressed constraints, to generate sequences of desired player actions. These action graphs are used as the basis for the spatial structure and content of game levels; they guide the layout process and indicate the required content related to such actions. We showcase our approach with a case study on a 3D dungeon crawler game. Results allow us to conclude that our control mechanisms are both expressive and powerful, effectively supporting designers to procedurally generate game levels.Computer Science - Media and Knowledge EngineeringIntelligent SystemsElectrical Engineering, Mathematics and Computer Scienc
Interaction of free surface waves with elastic and air-cushion platforms
No full textElectrical Engineering, Mathematics and Computer Scienc
Development of nature-oriented dairy farm systems with an optimization model: the case of ‘Farming for Nature’ in ‘de Langstraat’, the Netherlands
Get PDF‘Farming for Nature’, a relatively new policy instrument being tried out in the Netherlands, is evaluated. The concept has been designed to allow dairy farmers to improve nature conservation on their farms. Under the scheme, no manure, fertilizer, or feed – concentrates or roughage - may be imported into farm systems from external sources. The feasibility of such a self-sustaining system and the conditions required for it to deliver the desired results, are explored with a farm-based linear programming model known as FIONA (Farm based Integrated Optimization Model for Nature and Agriculture). The model is explained and applied to ‘de Langstraat’, a region in southern Netherlands. The results show that levels of production under the ‘Farming for Nature’ regime are dependent upon soil fertility and the proportion of land that is suitable for growing arable crops. If all available land on a dairy farm in the scheme is arable land, then high production levels of up to 7,500 kg milk per hectare can be realized. If only 30% of the farm area is suitable for arable crops, then only lower production levels, of about 6,600 kg milk per hectare can be realized. The scheme has positive ecological effects. Both nature and cultural landscape values may benefit significantly from the concept. Improvement in ecological terms however, carries a price in terms of agricultural income. An average dairy farm adopting the concept of ‘Farming for Nature’ experiences an income loss of approximately € 840 per hectare in the short-run (5-10 years). More important is the observation that the scale of such farms in the short-run might be too small to earn an attractive income for its workers, even when fully compensated according to European Union regulations.nature management, dairy farming system, linear programming, farm-economics, Farm Management, Land Economics/Use,
On convergence analysis and convergence enhancement of power system least-squares state estimators
No full textHydrologic response and transmission losses in arid and semiarid catchments
No full textCivil Engineering and Geoscience
