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61.
Yu Shen Jean-Yves Potvin Jean-Marc Rousseau Serge Roy 《Annals of Operations Research》1995,61(1):189-211
In this paper, we describe an expert consulting system for a dispatcher working in a courier service company. The system integrates interactive-graphic features and a learning module to support the dispatcher in his(her) task, and to suggest appropriate decisions when new requests come in. An experiment with a professional dispatcher is also reported. 相似文献
62.
The irredundant Ramsey number s(m, n) is the smallest p such that for every graph G with p vertices, either G contains an n-element irredundant set or its complement G contains an m-element irredundant set. Cockayne, Hattingh, and Mynhardt have given a computer-assisted proof that s(3, 7) = 18. The purpose of this paper is to give a self-contained proof of this result. © 1995 John Wiley & Sons, Inc. 相似文献
63.
To enable surface coils to be adapted to a wide variety of examinations and anatomical features, the authors present a flexible detector coupled with an auto tuning device. The conductive loop, which is a flexible mercury filled tube, can be used to obtain various shapes, such as a single flat 22-cm diameter loop or an 11-cm diameter two-turn coil. Tuning is carried out at 21 MHz (0.5 T field) by a microprocessor controlled varactor. Studies conducted on a phantom are used to evaluate the signal/noise ratio and the spatial sensitivity of the coil according to different geometrical arrangements (saddle-shaped and two-turn). The results are compared with those obtained with the constructor's spine coil. The studies of patients described show good image resolution, even in the case of short sequences with thin slices and restricted fields of view. The clinical results and those obtained on the phantom demonstrate the feasibility and value of the device, particularly in examining anatomical regions of different forms. 相似文献
64.
R. C. Barnà D. De Pasquale A. Italiano A. Trifirò M. Trimarchi C. Beck C. Bhattacharya F. Haas V. Rauch M. Rousseau O. Stezowsky A. Strazzeri 《Acta Physica Hungarica A》2002,16(1-4):281-289
The 132 MeV 16O + 58Ni reaction has been experimentally investigated by using coincident charged particle techniques. A closed-form theoretical approach, describing in a simple picture the non-equilibrium component and the evaporative one of the angular correlation between light particles and reaction residues emitted in a peripheral heavy-ion collision, is applied — in the hypotesis of a sequential process — to the (C,N,O)-α and (C,N,O)-p differential multiplicities for the 16O + 58Ni at 8.25 MeV/A deep inelastic collision. From this analysis some reaction mechanism information is deduced. 相似文献
65.
Kando M Fukuda Y Pirozhkov AS Ma J Daito I Chen LM Esirkepov TZh Ogura K Homma T Hayashi Y Kotaki H Sagisaka A Mori M Koga JK Daido H Bulanov SV Kimura T Kato Y Tajima T 《Physical review letters》2007,99(13):135001
In a plasma wake wave generated by a high power laser, modulations of the electron density take the shape of paraboloidal dense shells, moving almost at the speed of light. A counterpropagating laser pulse is partially reflected from the shells, acting as relativistic flying mirrors, producing a time-compressed frequency-multiplied pulse due to the double Doppler effect. The counterpropagating laser pulse reflection from the plasma wake wave accompanied by its frequency multiplication (with a factor from 50 to 114) was detected in our experiment. 相似文献
66.
Mazzarello R Cossaro A Verdini A Rousseau R Casalis L Danisman MF Floreano L Scandolo S Morgante A Scoles G 《Physical review letters》2007,98(1):016102
We have investigated the controversy surrounding the (sqrt[3] x sqrt[3]) R30 degrees structure of self-assembled monolayers of methylthiolate on Au(111) by first principles molecular dynamics simulations, energy and angle resolved photoelectron diffraction, and grazing incidence x-ray diffraction. Our simulations find a dynamic equilibrium between bridge site adsorption and a novel structure where 2 CH3S radicals are bound to an Au adatom that has been lifted from the gold substrate. As a result, the interface is characterized by a large atomic roughness with both adatoms and vacancies. This result is confirmed by extensive photoelectron and grazing incidence x-ray diffraction measurements. 相似文献
67.
Sequential Synthesis of 3 d–3 d, 3 d–4 d,and 3 d–5 d Hybrid Polyoxometalates and Application to the Electrocatalytic Oxygen Reduction Reactions 下载免费PDF全文
Dr. Guillaume Rousseau Shuangshuang Zhang Dr. Olivier Oms Dr. Anne Dolbecq Dr. Jérôme Marrot Dr. Rongji Liu Xinke Shang Prof. Guangjin Zhang Prof. Pierre Mialane 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(34):12153-12160
The Co7(AlePy)2 polyoxometalate, which encloses a {(PW9)2CoII7} core covalently bound to two free aminopyridine groups through bisphosphonate ligands ( AlePy ), has been isolated. It can be used as a precursor, allowing the synthesis of heterometallic hybrid compounds, as illustrated by the characterization of cobalt/zinc ( Co7(AlePyZn)2 ), cobalt/palladium ( Co7(AlePyPd)2 ), and cobalt/platinum ( Co7(AlePyPt)2 ) species. A composite based on the water‐insoluble precious metal‐free Co7(AlePyZn)2 compound and the low‐cost carbon material Vulcan XC‐72 has been selected as a cathode material ( Co7Zn/C ) for oxygen reduction reaction studies. The electrocatalytic performances of the Co7Zn/C hybrids were assessed at neutral and basic pH, showing that Co7Zn/C exhibits high selectivity for the four‐electron reduction of O2. Moreover, its durability is superior to that of a commercial Pt/C catalyst with 20 % loading. Also, comparative studies performed in the presence of methanol have indicated that Co7Zn/C has a much better tolerance to the crossover effect than Pt/C . Altogether, these results indicate for the first time that, even in neutral media, polyoxometalate/carbon composites can represent low‐cost oxygen reduction catalysts that can function stably, for a long time, and with high performance. 相似文献
68.
As a result of the increased focus on data literacy and data science across the world, there has been a large demand for professional development in statistics. However, exactly how these professional development opportunities should be structured remains an open question. The purpose of this paper is to describe the first iteration of a design experiment involving Project-SET (www.project-set.com) professional development program. Project-SET provided professional development to enhance teachers’ understanding of statistics concepts. The project constructed two learning trajectories for teacher learning and subsequently used the learning trajectories to structure the professional development curriculum. The main goal of this paper is to illustrate how the utilization of the teacher-learning trajectories to structure the professional development allowed participating teachers to develop several aspects of Statistics Knowledge for Teaching (Groth, 2013). 相似文献
69.
Gregory Rix Louis-Martin Rousseau Gilles Pesant 《The Journal of the Operational Research Society》2015,66(2):278-287
We present a tactical wood flow model that appears in the context of the Canadian forestry industry, and describe the implementation of a decision support system created for use by an industrial partner. In this problem, mill demands and harvested volumes of a heterogeneous set of log types are given over a multi-period planning horizon. Wood can be stored at the forest roadside before delivery at a financial cost. Rather than solve this as a network linear programme on the basis of out-and-back deliveries, we choose to model this problem as a generalization of a log-truck scheduling problem. By routing and scheduling the trucks in the resolution, this allows us to both anticipate potential backhaul opportunities for cost and fuel savings, and also minimize queuing times at log-loaders, management of which is a major concern in the industry. We model this problem as a mixed integer linear programme and solve it via column generation. The methodology is tested on several case studies. 相似文献
70.
Giovanelli E Leroux S Moisan L Carreyre H Thuéry P Buisson DA Meddour A Coustard JM Thibaudeau S Rousseau B Nicolas M Hellier P Doris E 《Organic letters》2011,13(15):4116-4119
Detailed investigations on one of the key steps of the superacidic fluorination of Vinca alkaloids that is the origin of C20' activation are reported. While two different pathways can be envisioned for the emergence of the transient secondary carbocationic intermediate, isotopic labeling experiments unambiguously revealed the involvement of a 1,2-hydride shift mechanism. 相似文献