BUNCH TECHNIQUE FOR SEMIONLINE WITH TWO GROUPS OF ITEMS

Предложен метод упаковки для задачи semionline с двумя группами предметов. Алгоритмом решения этой задачи является распределение предметов из первой группы с использованием групповой технологии, после чего применяется LS-алгоритм для назначения предметов из второй группы. Чтобы доказать оценку алгоритма, введены разные типы упаковок. В соответствии с весами предметов определены классы предметов. Предложен алгоритм распределения предметов из первой группы для получения необходимых упаковок. На втором этапе применяется алгоритм «в минимально загруженный» с наихудшей оценкой 17/9.Bunch technique for semionline with two groups of items is proposed in this paper. Algorithm to solve this problem is to distribute items from the first group bunch approach and after that apply LS-algorithm to assign items from the se­cond group. In order to prove the estimation of our algorithm is introduced different types of bunches to distribute all items from the first group such a way that only one of the entered types of bunches are obtained. During the second stage we use LS with worst case performance is at most 17/9

An efficient algorithm for semi-online multiprocessor scheduling with given total processing time

International audienceWe consider a semi-online multiprocessor scheduling problem with a given a set of identical machines and a sequence of jobs, the sum of whose processing times is known in advance. The jobs are to be assigned online to one of the machines and the objective is to minimize the makespan. The best known algorithm for this problem achieves a competitive ratio 1.6 (Cheng et al. in Theor Comput Sci 337:134–146, 2005). The best known lower bound is approximately 1.585 (Albers and Hellwig in Theor Comput Sci 443:1–9, 2012) if the number of machines tends to infinity. We present an elementary algorithm with competitive ratio equal to this lower bound. Thus, the algorithm is best possible if the number of machines tends to infinity

Designing periodic and aperiodic structures for nanophotinic devices.

330 p.Future all--optical networks will require to substitute the present electronic integrated circuitry by optical analogous devices that satisfy the compactness, throughput, latency and high transmission efficiency requirements in nanometer scale dimensions, outperforming the functionality of current networks. Thereby, existing dielectric materials do not confine light in a sufficiently small scale and so the physical size of these links and devices becomes unacceptable. In fact, if the optical chip does not exist in the liking of the electronic chip, photonic crystals have recently led to great hopes for a large-scale integration of optoelectronic components. Two-dimensional photonic crystals slabs obtained through periodic structuring of a planar optical waveguide, feature many characteristics which bring them closer to electronic micro-and nanostructures. This thesis explores non-trivial periodic and aperiodic dielectric nano-structures and to do so, we pose a photonic crystal design process guided by non-convex combinatory optimization techniques. In addition, this thesis proposes some novel coupling devices optimized to minimize insertion losses between silicon-on-insulator integrated waveguides and single mode optical fibers. Last but not least, this thesis explores periodic arrangements from a new perspective and reports on the first experimental evidence of topologically protected waveguiding in silicon. Furthermore, we propose and demonstrate that, in a system where topological and trivial defect modes coexist, we can probe them independently. Tuning the configuration of the interface, we observe the transition between a single topological defect and a compound trivial defect state