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An iterative learning approach for anticipatory traffic signal control on urban networks ; Viti, Francesco ; in Transportmetrica B: Transport Dynamics (2016) Detailed reference viewed: 110 (6 UL)An iterative learning approach for anticipatory traffic signal control on urban networks ; Viti, Francesco ; in Transportmetrica B: Transport Dynamics (2017), 5(4), 407-430 Detailed reference viewed: 79 (2 UL)An Iterative Learning Approach for Signal Control in Urban Traffic Networks ; Viti, Francesco ; in Proceedings of IEEE-ITS Conference (2013) Traffic signal control influences route choice in traffic networks, and may even determine whether a traffic system settles in equilibrium or destabilizes into oscillatory patterns. Ideally, a stable ... [more ▼] Traffic signal control influences route choice in traffic networks, and may even determine whether a traffic system settles in equilibrium or destabilizes into oscillatory patterns. Ideally, a stable equilibrium flow pattern should result from the interaction between control and route choice on a long-term horizon. This paper proposes an iterative learning approach for designing signal controls able to attract the system to equilibrium in an acceptable convergence speed. The traffic assignment model and combined traffic assignment and control problem are first introduced. An iterative learning control (ILC) based signal control is formulated and a basic model inversion method is analyzed. To deal with the nonlinearity of traffic system, a Newton based ILC algorithm is applied. Test in an example network verifies the effectiveness of the ILC method in achieving stable equilibrium in the traffic system. [less ▲] Detailed reference viewed: 110 (0 UL)An iterative Mixed Integer Linear Programming Approach to pursuit evasion problems in polygonal environments Thunberg, Johan ; in Proceedings of the 2010 IEEE International Conference on Robotics and Automation (ICRA) (2010) In this paper, we address the multi pursuer version of the pursuit evasion problem in polygonal environments. It is well known that this problem is NP-hard, and therefore we seek efficient, but not ... [more ▼] In this paper, we address the multi pursuer version of the pursuit evasion problem in polygonal environments. It is well known that this problem is NP-hard, and therefore we seek efficient, but not optimal, solutions by relaxing the problem and applying the tools of Mixed Integer Linear Programming (MILP) and Receding Horizon Control (RHC). Approaches using MILP and RHC are known to produce efficient algorithms in other path planning domains, such as obstacle avoidance. Here we show how the MILP formalism can be used in a pursuit evasion setting to capture the motion of the pursuers as well as the partitioning of the pursuit search region into a cleared and a contaminated part. RHC is furthermore a well known way of balancing performance and computation requirements by iteratively solving path planning problems over a receding planning horizon, and adapt the length of that horizon to the computational resources available. The proposed approach is implemented in Matlab/Cplex and illustrated by a number of solved examples. [less ▲] Detailed reference viewed: 91 (0 UL)Iterative observer-based state and parameter estimation for linear systems Aalto, Atte in ESAIM: Control, Optimisation and Calculus of Variations (2018), 24(1), 265-288 We propose an iterative method for joint state and parameter estimation using measurements on a time interval [0,T] for systems that are backward output stabilizable. Since this time interval is fixed ... [more ▼] We propose an iterative method for joint state and parameter estimation using measurements on a time interval [0,T] for systems that are backward output stabilizable. Since this time interval is fixed, errors in initial state may have a big impact on the parameter estimate. We propose to use the back and forth nudging (BFN) method for estimating the system’s initial state and a Gauss–Newton step between BFN iterations for estimating the system parameters. Taking advantage of results on the optimality of the BFN method, we show that for systems with skew-adjoint generators, the initial state and parameter estimate minimizing an output error cost functional is an attractive fixed point for the proposed method. We treat both linear source estimation and bilinear parameter estimation problems. [less ▲] Detailed reference viewed: 102 (11 UL)Iterative optimization for adaptive anticipatory control in urban traffic networks ; Viti, Francesco ; Scientific Conference (2015, July) Detailed reference viewed: 58 (1 UL)Iterative Precoder Design and User Scheduling for Block-Diagonalized Systems ; ; Ottersten, Björn in IEEE Transactions on Signal Processing (2012), 60(7), 3726-3739 The block diagonalization (BD) scheme is a low-complexity suboptimal precoding technique for multiuser multiple input-multiple output (MIMO) downlink channels, which completely precancels the multiuser ... [more ▼] The block diagonalization (BD) scheme is a low-complexity suboptimal precoding technique for multiuser multiple input-multiple output (MIMO) downlink channels, which completely precancels the multiuser interference. Accordingly, the precoder of each user lies in the null space of other users' channel matrices. In this paper, we propose an iterative algorithm using QR decompositions (QRDs) to compute the precoders. Specifically, to avoid dealing with a large concatenated matrix, we apply the QRD to a sequence of matrices of lower dimensions. One problem of BD schemes is that the number of users that can be simultaneously supported is limited due to zero interference constraints. When the number of users is large, a set of users must be selected, and selection algorithms should be designed to exploit the multiuser diversity gain. Finding the optimal set of users requires an exhaustive search, which has too high computational complexity to be practically useful. Based on the iterative precoder design, this paper proposes a low-complexity user selection algorithm using a greedy method, in which the precoders of selected users are recursively updated after each selection step. The selection metric of the proposed scheduling algorithm relies on the product of the squared row norms of the effective channel matrices, which is related to the eigenvalues by the Hadamard and Schur inequalities. An asymptotic analysis is provided to show that the proposed algorithm can achieve the optimal sum rate scaling of the MIMO broadcast channel. The numerical results show that the proposed algorithm achieves a good trade-off between sum rate performance and computational complexity. When users suffer different channel conditions, providing fairness among users is of critical importance. To address this problem, we also propose two fair scheduling (FS) algorithms, one imposing fairness in the approximation of the data rate, and another directly imposing fairness in the product of the sq- ared row norms of the effective channel matrices. [less ▲] Detailed reference viewed: 103 (2 UL)An Iterative Projection method for Synchronization of Invertible Matrices Over Graphs Thunberg, Johan ; Colombo, Nicolo ; Yue, Zuogong et al in 22nd International Symposium on Mathematical Theory of Networks and Systems (2016) This paper addresses synchronization of invertible matrices over graphs. The matrices represent pairwise transformations between n euclidean coordinate systems. Synchronization means that composite ... [more ▼] This paper addresses synchronization of invertible matrices over graphs. The matrices represent pairwise transformations between n euclidean coordinate systems. Synchronization means that composite transformations over loops are equal to the identity. Given a set of measured matrices that are not synchronized, the synchronization problem amounts to fining new synchronized matrices close to the former. Under the assumption that the measurement noise is zero mean Gaussian with known covariance, we introduce an iterative method based on linear subspace projection. The method is free of step size determination and tuning and numerical simulations show significant improvement of the solution compared to a recently proposed direct method as well as the Gauss-Newton method. [less ▲] Detailed reference viewed: 128 (10 UL)An iterative technique for bounding derivatives of solutions of Stein equations Döbler, Christian ; ; in Electronic Journal of Probability (2017), 22 Detailed reference viewed: 131 (12 UL)Itinéraires croisés. Luxembourgeois à l'étranger, étrangers au Luxembourg ; Scuto, Denis Book published by Editions Le Phare (1995) Detailed reference viewed: 114 (1 UL)Itinéraires et présences de souverains en Lotharingie (Ca. 850-ca.950). Questions sur la place de la région mosane Pettiau, Hérold Presentation (2011, September 12) This paper was given at a one-day workshop organised at the "Musée de l'Ardenne" in Charleville-Mézière (France) as part of a contribution made to an international research project dealing with the ... [more ▼] This paper was given at a one-day workshop organised at the "Musée de l'Ardenne" in Charleville-Mézière (France) as part of a contribution made to an international research project dealing with the Ardenne as a frontier-region in the early Middle Ages. As a part of an ongoing research on itineraries of Carolingian [less ▲] Detailed reference viewed: 25 (0 UL)Itinéraires luxembourgeois et européens.Evolutions et souvenirs: 1945-1985 ; Danescu, Elena ; Danescu, Elena Book published by Gnosis - 2nd edition (2004) Detailed reference viewed: 67 (2 UL)Itinéraires luxembourgeois et européens.Evolutions et souvenirs: 1945-1985 ; Danescu, Elena ; Danescu, Elena Book published by Gnosis - 1st edition (1998) Detailed reference viewed: 47 (0 UL)Itinéraires luxembourgeois et européens.Evolutions et souvenirs: 1945-1985 ; Danescu, Elena ; Danescu, Elena Book published by GNOSIS - 3th edition. Fully revised and corrected edition (2010) l Detailed reference viewed: 41 (2 UL)Itô's and Tanaka's type formulae for the stochastic heat equation: the linear case ; Nourdin, Ivan ; in Journal of Functional Analysis (2005), 228(1), 114-143 Detailed reference viewed: 51 (1 UL)Ito's formula for Walsh's Brownian motion and applications Hajri, Hatem ; in Statistics & Probability Letters (2014) Detailed reference viewed: 197 (31 UL)An Itô's type formula for the fractional Brownian motion in Brownian time Nourdin, Ivan ; in Electronic Journal of Probability (2014), 19(99), 1-15 Detailed reference viewed: 85 (1 UL)ITU Instruments under the Perspective of General International Law Hofmann, Mahulena in Jorgenson, Corinne (Ed.) Proceedings of the IISL (2014) Detailed reference viewed: 84 (7 UL)Iuwers zornes unmâze missevellet uns sêre. Legitimität von Maßlosigkeit im mittelalterlichen Erzählkosmos Bendheim, Amelie in Das Mittelalter (2018), 23(1), 11-28 Ausgehend von den Defiziten bestehender Ansätze zur Beschreibung des Helden in mittelalterlichen Erzählwelten, soll die Maßlosigkeit (unmâze) als neue literaturgeschichtliche Kategorie funktionalisiert ... [more ▼] Ausgehend von den Defiziten bestehender Ansätze zur Beschreibung des Helden in mittelalterlichen Erzählwelten, soll die Maßlosigkeit (unmâze) als neue literaturgeschichtliche Kategorie funktionalisiert werden. Entgegen der konzeptuellen, binären Typisierung des Protagonisten als ‚Held’ bzw. ‚Ritter’ bildet sie ein flexibles Modell, das relational operiert und damit erlaubt, graduelle Unterscheidungen zwischen den Texten vorzunehmen. Am Beispiel heldenepischen (‚Nibelungenlied’) und romanhaften (‚Flore und Blanscheflur’, ‚Wigalois’) Erzählens im Mittelalter wird gezeigt, wie mit dem maßlosen Helden narrativ umgegangen wird. Dabei liegt der Fokus insbesondere auf der unterschiedlichen Bewertung seines Handelns: Kann sich der Held im Epos über soziale Normen und geltende Gesetze hinwegsetzen (Siegfried bei der Brautwerbung, Hagen mit dem Mord an Siegfried) ohne dafür bestraft zu werden, tritt die Maßlosigkeit im höfischen Roman stärker in den Bereich der Ratio: Sie wird dabei zum einen begrenzt und ‚bemessen’, zum anderen wird maßloses Handeln nun strikt sanktioniert und unterbunden. Unter Bezugnahme auf aktuelle Ausprägungen der Maßlosigkeit im gesellschaftspolitischen Kontext, tritt das Konzept der Maßlosigkeit als unverändert produktives Muster hervor. Seine gesellschaftliche Relevanz regt zu einer epochenübergreifenden literaturgeschichtlichen Inanspruchnahme an, die sich zum Ziel setzt, die Literaturgeschichte als Geschichte der Maßlosigkeit zu neu zu begreifen. [less ▲] Detailed reference viewed: 130 (2 UL)IV Grid Plugtests: composing dedicated tools to run an application efficiently on Grid'5000 Besseron, Xavier ; ; et al Presentation (2008, February 12) Exploiting efficiently the resources of whole Grid'5000 with the same application requires to solve several issues: 1) resources reservation; 2) application's processes deployment; 3) application's tasks ... [more ▼] Exploiting efficiently the resources of whole Grid'5000 with the same application requires to solve several issues: 1) resources reservation; 2) application's processes deployment; 3) application's tasks scheduling. For the IV Grid Plugtests, we used a dedicated tool for each issue to solve. The N-Queens contest rules imposed ProActive for the resources reservations (issue 1). Issue 2 was solved using TakTuk which allows to deploy a large set of remote nodes. Deployed nodes take part in the deployment using an adaptive algorithm that makes it very efficient. For the 3rd issue, we wrote our application with Athapascan API whose model is based on the concepts of tasks and shared data. The application is described as a data-flow graph using the Shared and Fork keywords. This high level abstraction of hardware gives us an efficient execution with the Kaapi runtime engine using a work-stealing scheduling algorithm to balance the workload between all the distributed processes. [less ▲] Detailed reference viewed: 11 (1 UL) |
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