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Efficient fastest-path computations for road maps

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Computational Visual Media 2021年第2期7卷 267-281页

作者： Renjie Chen craig Gotsman University of Science and Technology of China HefeiChina New Jersey Institute of Technology NewarkNJUSA

In the age of real-time online traffic information and GPS-enabled devices,fastest-path computations between two points in a road network modeled as a directed graph,where each directed edge is weighted by a“travel time”value,are becoming a standard feature of many navigation-related *** support this,very efficient computation of these paths in very large road networks is *** paths may be computed as minimal-cost paths in a weighted directed graph,but traditional minimal-cost path algorithms based on variants of the classical Dijkstra algorithm do not scale well,as in the worst case they may traverse the entire graph.A common improvement,which can dramatically reduce the number of graph vertices traversed,is the A*algorithm,which requires a good heuristic lower bound on the minimal *** introduce a simple,but very effective,heuristic function based on a small number of values assigned to each graph *** values are based on graph separators and are computed efficiently in a preprocessing *** present experimental results demonstrating that our heuristic provides estimates of the minimal cost superior to those of other *** experiments show that when used in the A*algorithm,this heuristic can reduce the number of vertices traversed by an order of magnitude compared to other heuristics.

关键词： shortest-path road map heuristic GPS navigation A^(*)search

New Identities for Weak KAM Theory(For Haim Brezis,in continuing admiration)

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Chinese Annals of Mathematics,Series B 2017年第2期38卷 379-392页

作者： Lawrence craig EVANS Department of Mathematics University of CaliforniaBerkeleyUSA.

This paper records for the Hamiltonian H =1/2|p|~2+ W(x) some old and new identities relevant for the PDE/variational approach to weak KAM theory.

关键词： Weak KAM theory, Effective Hamiltonian, Hamiltonian dynamics

Regarding the Distribution of Glue in the Pion

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Chinese Physics Letters 2021年第8期38卷 17-22页

作者： Lei Chang craig D.Roberts School of Physics Nankai UniversityTianjin 300071China School of Physics Nanjing UniversityNanjing 210093China Institute for Nonperturbative Physics Nanjing UniversityNanjing 210093China

Understanding why the scale of emergent hadron mass is obvious in the proton but hidden in the pion may rest on mapping the distribution functions(DFs)of all partons within the pion and comparing them with those in the proton;and since glue provides binding in quantum chromodynamics,the glue DF could play a special *** reliable predictions for the proton’s DFs is difficult because the proton is a three-valence-body bound-state *** sketched herein,the situation for the pion,a two-valence-body problem,is much better,with continuum and lattice predictions for the valence-quark and glue DFs in *** beginning of theory alignment is timely because experimental facilities now either in operation or planning promise to realize the longstanding goal of providing pion targets,thereby enabling precision experimental tests of rigorous theory predictions concerning Nature’s most fundamental Nambu-Goldstone bosons.

关键词： valence thereby rigorous

Resolving the Bethe–Salpeter Kernel

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Chinese Physics Letters 2021年第7期38卷 17-22页

作者： Si-Xue Qin craig D.Roberts Department of Physics Chongqing UniversityChongqing 401331China School of Physics Nanjing UniversityNanjing 210093China Institute for Nonperturbative Physics Nanjing UniversityNanjing 210093China

A novel method for constructing a kernel for the meson bound-state problem is *** produces a closed form that is symmetry-consistent(discrete and continuous)with the gap equation defined by any admissible gluon-quark vertex,Γ.Applicable even when the diagrammatic content ofΓis unknown,the scheme can foster new synergies between continuum and lattice approaches to strong *** framework is illustrated by showing that the presence of a dressed-quark anomalous magnetic moment inΓ,an emergent feature of strong interactions,can remedy many defects of widely used meson bound-state kernels,including the mass splittings between vector and axial-vector mesons and the level ordering of pseudoscalar and vector meson radial excitations.

关键词： meson quark admissible

Dielectrophoretic assembly of carbon nanotubes and stability analysis

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Progress in Natural Science:Materials International 2013年第4期23卷 367-373页

作者： Libao An craig Friedrich College of Mechanical Engineering Hebei Provincial Key Laboratory of Inorganic Nonmetallic MaterialsHebei United University Department of Mechanical Engineering-Engineering Mechanics Multi-Scale Technologies InstituteMichigan Technological University

Nanoscale dimensions and remarkable properties of carbon nanotubes make them promising building blocks for *** requirement is the need to manipulate single or multiple carbon nanotubes to bridge electronic *** this paper,multi-walled carbon nanotubes with a variety of sizes are assembled onto electrodes using alternative current electric felds by *** effect of the dielectrophoretic parameters and the nanotube size as well as the length uniformity on the assembly is experimentally ***–voltage characteristics of assembled carbon nanotubes are *** experimental results showed that both the dielectrophoretic parameters and length uniformity of carbon nanotubes have an infuence on the stability of assembly *** uniform carbon nanotubes with an appropriate length and suffcient stiffness,which are more controllable by dielectrophoresis,is necessary for an assembly of a small number of carbon nanotubes.

关键词： Carbon nanotube Assembly Dielectrophoresis Process parameter Stability

Use of mycophenolate mofetil in inflammatory bowel disease

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World Journal of Gastroenterology 2009年第13期15卷 1594-1599页

作者： Terrence Tan Ian craig Lawrance Department of Gastroenterology Fremantle Hospital Centre for Inflammatory Bowel Diseases Fremantle Hospital Department of Medicine and Pharmacology University of Western AustraliaFremantle Hospital

AIM:To assess the efficacy and safety of mycophenolate mofetil(MMF)prospectively in inflammatory bowel disease(IBD)patients intolerant or refractory to conventional medical ***:Crohn's disease(CD)or ulcerative colitis/ IBD unclassified(UC/IBDU)patients intolerant or refractory to conventional medical therapy received MMF(500-2000 mg bid).Clinical response was assessed by the Harvey Bradshaw index(HBI)or colitis activity index(CAI)after 2,6 and 12 mo of therapy,as were steroid usage and adverse ***:Fourteen patients(9 CD/5 UC/IBDU;8M/6F;mean age 50.4 years,range 28-67 years)were treated and prospectively assessed for their response to oral *** the 11 patients who were not in remission on commencing MMF,7/11(63.6%)achieved remission by 8 *** 3 patients in remission on commencing MMF maintained their *** patients were still on MMF at 6 mo with 9/14(64.3%)in remission,while of 12 patients followed for 12 mo,8 were in remission without dose escalation(66.7%).Three patients were withdrawn from the MMF due to drug *** were no serious adverse events attributed due to the ***:MMF demonstrated efficacy in the management of difficult *** appeared safe,well tolerated and efficacious for both short and long-term therapy,without the need for dose *** evaluation of MMF comparing it to conventional immunosuppressants is required.

关键词： Inflammatory bowel disease Mycophenolatemofetil Therapy Crohn's disease Ulcerative colitis

Single-lens dynamic z-scanning for simultaneous in situ position detection and laser processing focus control

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Light(Science & Applications) 2023年第12期12卷 2655-2667页

作者： Xiaohan Du Camilo Florian craig B.Arnold Department of Mechanical and Aerospace Engineering Princeton UniversityPrincetonNJ 08544USA Department of Systems Engineering City University of Hong KongHong KongChina Institut für Werkstofftechnik Universität Kassel34125 KasselGermany Princeton Materials Institute Princeton UniversityPrincetonNJ 08544USA

Existing auto-focusing methods in laser processing typically include two independent modules,one for surface detection and another for z-axis *** latter is mostly implemented by mechanical z stage motion,which is up to three orders of magnitude slower than the lateral processing *** alleviate this processing bottleneck,we developed a single-lens approach,using only one high-speed z-scanning optical element,to accomplish both in situ surface detection and focus control quasi-simultaneously in a dual-beam *** probing beam scans the surface along the z-axis continuously,and its reflection is detected by a set of confocal *** on the temporal response of the detected signal,we have developed and experimentally demonstrated a dynamic surface detection method at 140-350 kHz,with a controlled detection range,high repeatability,and minimum linearity error of 1.10%.Sequentially,by synchronizing at a corresponding oscillation phase of the z-scanning lens,the fabrication beam is directed to the probed z position for precise focus ***,our approach provides instantaneous surface tracking by collecting position information and executing focal control both at 140-350 kHz,which significantly accelerates the axial alignment process and offers great potential for enhancing the speed of advanced manufacturing processes in three-dimensional space.

关键词： dynamic beam simultaneous

Rethinking random Hough Forests for video database indexing and pattern search

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Computational Visual Media 2016年第2期2卷 143-152页

作者： craig Henderson Ebroul Izquierdo Multimedia and Vision Research Group School of Electronic Engineering and Computer ScienceQueen Mary University of London

Hough Forests have demonstrated effective performance in object detection tasks, which has potential to translate to exciting opportunities in pattern search. However, current systems are incompatible with the scalability and performance requirements of an interactive visual search. In this paper, we pursue this potential by rethinking the method of Hough Forests training to devise a system that is synonymous with a database search index that can yield pattern search results in near real time. The system performs well on simple pattern detection, demonstrating the concept is ***, detection of patterns in complex and crowded street-scenes is more challenging. Some success is demonstrated in such videos, and we describe future work that will address some of the key questions arising from our work to date.

关键词： Hough Forests pattern detection pattern search machine learning

Multifaceted Bioinspiration for Improving the Shaft Resistance of Deep Foundations

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Journal of Bionic Engineering 2020年第5期17卷 1059-1074页

作者： Seyed Ali Aleali Paola Bandini craig Michael Newtson Center for Bio-mediated and Bio-inspired Geotechnics Department of Civil EngineeringNew Mexico State UniversityLas CrucesNew Mexico 88003-8001USA

This paper describes the bioinspiration process to derive design concepts for new deep foundation systems that have greater axial capacity per unit volume of pile material compared to conventional deep *** study led to bioinspired ideas that provide greater load capacity by increasing the pile shaft *** bioinspiration approach used problem-solving strategies to define the problem and transfer strategies from biology to geotechnical *** bioinspiration considered the load transfer mechanism of hydroskeletons and the anchorage of the earthworm,razor clam,kelp,and lateral roots of *** biostrategies that were transferred to the engineering domain included a flexible but incompressible core,passive behaviour against external loading,a longitudinally split shell that allows expansion for anchorage,and lateral root-type or setae-type anchoring *** concepts of three bioinspired deep foundation systems were proposed and *** advantage of this approach was illustrated with two examples of the new laterally expansive pile in drained sand under axial *** finite element analysis of these examples showed that the new laterally expansive pile can provide considerably greater load capacity compared to a conventional cylindrical pile due to the increased lateral confining pressure developed along the expanded pile core.

关键词： bioinspiration expansion anchorage deep foundation pile capacity frictional resistance