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宇宙大灾变爆炸星、黑洞及宇宙测绘

国外科技新书评介 2008年第7期 23-24页

作者： J．craig wheeler 邓劲松不详中国科学院国家天文台

这是一本非常优秀的天文科普书籍，源于作者在大学开讲多年的公共入门课程，深入浅出地讲述了当代天文学和宇宙研究中非常吸引人的一些话题。内容远不止书名所涵指的超新星、伽玛射线暴等恒星爆炸现象，还有对恒星及双星的演化、吸积盘... 详细信息

这是一本非常优秀的天文科普书籍，源于作者在大学开讲多年的公共入门课程，深入浅出地讲述了当代天文学和宇宙研究中非常吸引人的一些话题。内容远不止书名所涵指的超新星、伽玛射线暴等恒星爆炸现象，还有对恒星及双星的演化、吸积盘、白矮星、中子星、黑洞、宇宙加速膨胀等相关天文现象以及背后的物理所做的全面而清晰的阐述，

关键词：宇宙加速膨胀爆炸现象黑洞灾变测绘伽玛射线暴天文现象天文学

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

Impressions of Parton Distribution Functions

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Chinese Physics Letters 2024年第12期41卷 53-59页

作者： Yang Yu craig D.Roberts School of Physics Nanjing UniversityNanjing 210093China Institute for Nonperturbative Physics Nanjing UniversityNanjing 210093China

Parton distribution functions(DFs)have long been recognized as key measures of hadron ***,theoretical prediction of such DFs is becoming possible using diverse methods for continuum and lattice analyses of strong interaction(QCD)matrix *** developments include a demonstration that continuum and lattice analyses yield mutually consistent results for all pion DFs,with behavior on the far valence domain of light-front momentum fraction that matches QCD *** is also delivering an understanding of the distributions of proton mass and spin amongst its constituents,which varies,of course,with the resolving scale of the measuring *** of the pion DF and proton spin developments are sketched herein,along with some novel perspectives on gluon and quark orbital angular momentum.

关键词： structure. mutually sketch

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