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排序方式: 共有1519条查询结果,搜索用时 15 毫秒
31.
Ciesielczyk Tomasz Cabrera Alberto Oleksiak Ariel Piątek Wojciech Waligóra Grzegorz Almeida Francisco Blanco Vicente 《Journal of Scheduling》2021,24(5):489-505
Journal of Scheduling - Rapid growth of demand for remote computational power, along with high energy costs and infrastructure limits, has led to treating power usage as a primary constraint in... 相似文献
32.
A two‐level detector of short‐term unique changes in time series based on a similarity method
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In the paper, a novel two‐level algorithm of time‐series change detection is presented. In the first level, to identify non‐stationary sequences in a processed signal, preliminary detection of events is performed with a short‐term prediction comparison. In the second stage, to confirm the changes detected in the first level, a similarity method aimed at identification of unique changes is employed. The detection of changes in a non‐stationary time series is discussed, implemented algorithms are described and the results produced on a sample four financial time series are shown. General conditions for implementing the proposed algorithm as an immune‐like event detector are discussed. 相似文献
33.
Tomasz Idziaszek Michał Skrzypczak Mikołaj Bojańczyk 《Theory of Computing Systems》2016,58(4):614-663
An infinite tree is called thin if it contains only countably many infinite branches. Thin trees can be seen as intermediate structures between infinite words and infinite trees. In this work we investigate properties of regular languages of thin trees. Our main tool is an algebra suitable for thin trees. Using this framework we characterize various classes of regular languages: commutative, open in the standard topology, and definable in weak MSO logic among all trees. We also show that in various meanings thin trees are not as rich as all infinite trees. In particular we observe a collapse of the parity index to the level (1, 3) and a collapse of the topological complexity to co-analytic sets. Moreover, a gap property is shown: a regular language of thin trees is either weak MSO-definable among all trees or co-analytic-complete. 相似文献
34.
In this work, we present a method of decomposition of arbitrary unitary matrix \(U\in \mathbf {U}(2^k)\) into a product of single-qubit negator and controlled-\(\sqrt{\text{ NOT }}\) gates. Since the product results with negator matrix, which can be treated as complex analogue of bistochastic matrix, our method can be seen as complex analogue of Sinkhorn–Knopp algorithm, where diagonal matrices are replaced by adding and removing an one-qubit ancilla. The decomposition can be found constructively, and resulting circuit consists of \(O(4^k)\) entangling gates, which is proved to be optimal. An example of such transformation is presented. 相似文献
35.
In this work we aim at proving central limit theorems for open quantum walks on \({\mathbb {Z}}^d\). We study the case when there are various classes of vertices in the network. In particular, we investigate two ways of distributing the vertex classes in the network. First, we assign the classes in a regular pattern. Secondly, we assign each vertex a random class with a transition invariant distribution. For each way of distributing vertex classes, we obtain an appropriate central limit theorem, illustrated by numerical examples. These theorems may have application in the study of complex systems in quantum biology and dissipative quantum computation. 相似文献
36.
Slawomir J. Ambroziak Ryszard J. Katulski Jaroslaw Sadowski Jacek Stefanski 《通讯和计算机》2013,(9):1247-1252
The aim of this paper is the path loss modelling for the radiolocation services in radio communication networks, particularly in cellular networks. The main results of the measurements obtained in the physical layer of the UMTS are introduced. A new method for the utilization of the multipath propagation phenomenon to improve the estimation of the distance between the MS (mobile station) and the BS (base station) is outlined. This method significantly increases the quality of location services in systems which use a radio interface with DS (direct sequence) CDMA (code division multiple access). 相似文献
37.
A common way of computing all efficient (Pareto optimal) solutions for a biobjective combinatorial optimisation problem is to compute first the extreme efficient solutions and then the remaining, non-extreme solutions. The second phase, the computation of non-extreme solutions, can be based on a “k-best” algorithm for the single-objective version of the problem or on the branch-and-bound method. A k-best algorithm computes the k-best solutions in order of their objective values. We compare the performance of these two approaches applied to the biobjective minimum spanning tree problem. Our extensive computational experiments indicate the overwhelming superiority of the k-best approach. We propose heuristic enhancements to this approach which further improve its performance. 相似文献
38.
Zeyad A. Almutairi Tomasz Glawdel Carolyn L. Ren David A. Johnson 《Microfluidics and nanofluidics》2009,6(2):241-251
This study presents a new Y-channel design for measuring the zeta potential and surface conductance of a solid-liquid pairing
using the current monitoring technique. The new design improves the throughput and reliability of the testing apparatus since
the displacement between two solutions can be repeated many times without interfering with the experiments. It also increases
the accuracy of the measurement by producing sharper start and end transitions for the current–time plot of the solution displacement
process. In this design, efforts have been made to minimize the effects of electrolysis, Joule heating and undesired pressure
driven flow on the measurements. An improvement on the current–time slope analysis is also presented. The Y-channel design
was validated by comparing zeta potential measurements to published results. The zeta potential of several biological buffers
relevant to the microfluidic community in plasma treated PDMS/PDMS and PDMS/Glass microchannels are presented. Preliminary
studies of surface conductivity measurements using the Y-channel design were also conducted and are briefly discussed. 相似文献
39.
Małgorzata Misiak Michał Skowicki Tomasz Lipiński Agnieszka Kowalczyk Katarzyna Prorok Sebastian Arabasz Artur Bednarkiewicz 《Nano Research》2017,10(10):3333-3345
Versatile optimization of the synthesis method and composition of Yb3+ and Tm3+ co-doped CaF2 nanoparticles as well as a novel biofunctionalization method were developed and evaluated.Through multistep synthesis,the luminescence intensity of the Tm3+ activator was enhanced by more than 10-fold compared to standard one-step synthesis.The proposed methods were used to homogenously distribute the doping ions within the nanoparticle's volume and thus reduce luminescence quenching.Optimization of dopant ions concentration led to the selection of the most efficient visible and near-infrared up-converting nanoparticles,which were CaF2 doped with 10% Yb3+ 0.05% Tm3+ and 20% Yb3+ 0.5% Tm3+,respectively.To illustrate the suitability of the synthesized nanoparticles as bio-labels,a dedicated biofunctionalization method was used,and the nanoparticles were applied for labeling and imaging of Candida albicans cells.This method shows great promise because of extremely low background and high specificity because of the presence of the attached molecules. 相似文献
40.
Transistors: Impact of Interfacial Microstructure on Charge Carrier Transport in Solution‐Processed Conjugated Polymer Field‐Effect Transistors (Adv. Mater. 11/2016)
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