226 research outputs found
The city of the crescent; with pictures of Harem life, or The turks in 1854. By Gordon O.L. Gordon Trenery, Esq. Author of "the morning Land" etc. etc. In two volumes London΄Charles J. skeet 10, king William street, Charing cross. 1855.
No full textPreface: by Trenery CordonDedication:Content description: Detailed contentsIllustration: 2 (Views ,)Pagination: PP16+303P, PP10+309+1PPVolumes: 2Text Genre:ProseEpilogue: as conclusion at the last chapterIllustration: 2 (τοπία ,
An approximate solution of loaded hyperbolic equation with homogenios boundary conditions
No full textО.Л. Бозиев,
Институт информатики и проблем регионального управления
Кабардино-Балкарского научного центра РАН, г. Нальчик, Российская Федерация
E-mail: [email protected]. O.L. Boziev
Institute of Computer Science and Problems of Regional Management of KBSC
of the Russian Academy of Sciences, Nal'chik, Russian Federation
E-mail: [email protected]Получена формула приближенного решения начально-краевой задачи
для нагруженного гиперболического уравнения, для нахождения которого
используется априорная оценка решения поставленной задачи. The article proposes a method for solving hyperbolic equation with a spatial variable integral of the
natural powers of the unknown function modulus, whereby it is loaded. The author considers an initial
boundary value problem with homogeneous boundary conditions. Scalar products of the equation by
various functionals and subsequent conversions make it possible to obtain a priori estimates of solutions
of the problem in various spaces. By successive integration over the spatial variable the reduction to an
ordinary differential equation associated with the initial one is produced. Its approximate solution is
sought using a priori estimates that are obtained. Found function leads to the formula that expresses the
approximate solution to the original problem through the right parts of the initial conditions
Robust model-based optimization of evacuation guidance
No full textLarge scale disasters, such as floods and fires, cause many casualties. This risk of casualties is reduced by evacuating the people from the threatened region. By guiding these people, i.e. instructing them when and where to go, the efficiency of the evacuation is increased. This means that, for example, the time needed for the evacuation is reduced. This thesis discusses the literature on optimization methods for car-based evacuation guidance. While many optimization methods are developed, the attention for uncertainty and compliance behavior in these methods is limited. This while these factors are of great importance for evaluating guidance in a realistic way. These findings are the reason to ask the following question: How can evacuation guidance be optimized in an efficient way, while incorporating uncertainty and compliance behavior? This thesis answers this question by formulating problems, presenting solution approaches and analyzing the results of case studies. The problem formulations contain decision variables representing guidance, consisting of departure time, route, and destination instructions for all evacuees. An objective function expresses the performance of this guidance. A travel behavior model and a traffic propagation model are included in the problem formulation to evaluate the guidance resulting in the performance value. The formulations and approaches are flexible with respect to the modeling assumptions. This is important because of the high degree of development of evacuation models. The first specific problem formulation presented in this thesis incorporates compliance behavior in the optimization of evacuation guidance. This problem is solved by a metaheuristic based on ant colony optimization. The method is applied to develop evacuation guidance for a hypothetical flood of part of The Netherlands. This case study shows that the optimized guidance increases the evacuation efficiency compared to no guidance or guidance developed by simple rules. This can be explained by the spread of travelers over time and space. The case study also shows that the solution approach results in a solution which effectiveness is close to the effectiveness of the optimal solution. The problem formulation is extended such that all kinds of uncertainty, like uncertainty in the demand, the behavior and the capacity, can be incorporated. This formulation is based on scenarios, which are representations of the uncertainty. Two procedures to select these scenarios are proposed, i.e. a deterministic procedure which results in a set of scenarios that is constant over the iterations of the solution approach, and a stochastic procedure that results in varying scenarios over the iterations. A case study shows the usefulness of incorporating uncertainty in the evacuation problem. For most cases holds that the efficiency of the evacuation increases when uncertainty is incorporated. The case study also shows that incorporating uncertainty is computationally demanding. Solving the evacuation problem is computationally expensive because of a high number of decision variables and high evaluation costs. A fixed-point approach is presented that efficiently optimizes evacuation guidance, in particular route guidance. This approach decomposes the original problem into simpler problems that are iteratively solved resulting in an approximate solution to the original problem. This approach overcomes the difficulties associated with the original problem. A case study shows that the fixed-point approach substantially speeds up the optimization of route guidance, while maintaining a comparable effectiveness of the resulting guidance. This thesis gives new insights in how beneficial evacuations are and how realistic plans can be optimized efficiently. The presented methods are ready for use in practice regarding the development of car-based evacuation guidance. Guidance can be optimized and, if available, it can be compared with existing plans. The guidance will be part of a broader plan that includes, for example, evacuation by public transport and communication and operation strategies.Transport & PlanningCivil Engineering and Geoscience
Cheap red wine
No full text'Cheap Red Wine’ is a poem that plays with the intimacy felt sometimes between readers and their favourite authors, in this case Baudelaire. The feeling that some authors -even those long dead-somehow are with us, somehow know us better than we know ourselves. That if we listen intently enough, the words will be embodied and we can converse with the author we care about. Of course, as the title suggests, a little red wine can help things along
An Analytical Performance Evaluation of a Coded OFDM-Based Transmission Scheme, using a Markov Model for a Frequency Selective Channel
No full textIn this report the performance of an error-correcting code on a wide-band frequency selective Rayleigh fading channel with an OFDM- based transmission scheme is estimated by means of an analytical model. In the European dTTb project, a transmission scheme for a new digital terrestrial TV system is under development. This scheme uses OFDM to divide the wide-band channel into a large number of narrow-band subchannels to tackle the frequency selectivity and to combat the Inter-Symbol Interference. The transmission scheme must allow portable (indoor) reception which implies that the transmission channel is a multipath channel. This multipath channel suffers from frequency selective fading. The individual subchannels will have different but mutually dependent signal powers at the receiver. The dependency degrades the performance of an error-correcting code, designed to correct random errors, with respect to an infinitely interleaved fading channel. On an infinitely interleaved fading channel it is assumed that the individual subchannels have mutually independent signal powers, i.e., where random errors occur. In this report estimations of the performances of binary [n,k,d] BCH codes on this particular channel are made by using an analytical model. This model is an extended Gilbert-Elliott model which uses a Markov chain. The Markov chain performs a kind of quantization of the received signal-to-noise ratio within one subchannel. Further, it models the dependency between the signal powers of the subchannels.Electrical Engineering, Mathematics and Computer ScienceTelecommunicatie- en Verkeersbegeleidingssysteme
Implementeren van een versnelling van de CONTACT-programmatuur met behulp van de Graphics Processing Unit
No full textHet versnellen van CONTACT door het implementeren van Fast Fourier Transformaties op de GPU met de CUDA en de cuFFT bibliotheek. Met daarna onderzoek over wat de versnelling van de FFTs kan zijn.MathematicsElectrical Engineering, Mathematics and Computer Scienc
Design of jacket lifting and hang-off point for the Seesaw barge jacket removal concept
No full textThe first platforms for oil and gas production in the North Sea have been installed around 1970. Since then about 500 platforms have been built to explore the North Sea oil and gas fields. Now, after 30 years of use, the first platforms are abandoned, creating a demand for innovative and economical removal concepts. Heerema Marine Contractors (HMC), considered to be the world market leader in the installation and transport of offshore platforms, has developed the Seesaw barge jacket removal concept. The jacket is lifted in one section or in the largest section possible (by the SSCV 'Thialf') and tilted onto a barge (the H-851-barge) in this concept. The rotation of the jacket during the removal procedure reflects the seesaw principle. Previous studies at HMC proved the Seesaw barge concept to be feasible for the removal of typical North Sea jackets. The Seesaw barge removal concept combines the capabilities and capacities of existing HMC equipment. An important aspect of the Seesaw removal barge concept is the optimal use of the jacket buoyancy during the removal procedure by submerging the stern of the H-851 barge. Other advantages are the minimum amount of sub sea operations and the possibility to re-use the jackets. The Seesaw barge removal concept consists of four phases. 1. Upending of the Extended Tilting Beams (ETB' s) 2. Mating and load transfer of the jacket 3. Rotation of jacket onto H-851 barge 4. Transportation on the barge Objectives ofthe thesis study \u95 The primary objective of the thesis study is to design a lifting and hang-off system, compatible with the jacket configuration and strength, for jackets, that will be removed with the Seesaw barge removal concept \u95 The secondary objective is to make the lifting and hang-off system re-usable or adjustable for jackets with different dimensions and structural configurations.Hydraulic EngineeringCivil Engineering and Geoscience
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