从物理学发展看MEMS的跨学科研究

本文简述了微机电系统（MEMS）在各领域的广泛应用，以物理学观点出发分析研究了MEMS器件设计中互相关联的多物理场耦合问题．指出新技术学科存在于物理学发展本身，物理学是MEMS和许多交叉科学发展的坚实基础．     

我国物理学的发展历程

中国古代的学者很关注对自然现象的观察和理解，他们认为对自然规律的认识，对于每个人的人生观与人格的形成至关重要．当时的思想家认为自然界的规律和人文社会的规律是统一的，人文社会的法则也应该归结为天地、自然的法则；后来有人把这个观点概括为“天人合一”．从这点来看，当时的物理学与哲学是混为一体的．因此“物理”一词在2300年前的先秦时期就出现了，     

从20世纪的物理学看中国科学的发展

我的报告分为三个部分：一、从长距离的眼光看近代物理学的发展 二、中国近代物理学的发展历史 三、下一世纪中国近代物理学发展前景的个人看法。     

原子物理学的学术战略地位与素质教育中的作用

探讨了原子物理学在现代科学技术中的学术战略地位以及素质教育中的重要作用，指出了在科教兴国、大力发展高科技的今天，原子物理学的教学只能加强、不能削弱。     

物理学促使战场概念不断拓展--为2005国际物理年而作

近百年来，由于物理学领域的许多重大突破，奠定了现代科学技术的理论基础，催生了许多新型武器装备，促使战场概念不断拓展．     

光和实物的统一性与物理学基础探讨（Ⅰ）：相对论和量子论带来的困惑

本文通过对现有理论和实验事实的考察，对电磁波或场作为物质看待提出疑问；对于相对论，指出它对光与实物缺乏统一的认识和对等的处理方式；关于量子论，重点对波粒二重性解释的论战作了简介和简评；最后，怀着自然界具有客观实在性和统一性的信念，对所述的观念上的矛盾的起因做了推测．     

21世纪物理学的成就

20世纪以来，由于物理学理论的重大突破，诞生了相对论和量子论推动了以原子能、激光、通信、计算机、微电子、新型材料、基因工程、纳米技术、航天技术等为代表的现代科学技术迅猛发展，从而使物理学成为当代工程技术的重大支柱．物理知识和研究方法已渗透到各学科，成为许多新兴学科、交叉学科和高新技术产业的重要基础．进入21世纪各国都非常重视物理学的发展，取得了一系列的成果．主要表现在以下几个方面．     

物理学中的理想模型

物理学是现代科学技术的基础，它的成就和研究方法已渗透到了几乎所有的科学领域，而且在培养思维能力和实验能力等方面有不可替代的作用．物理学研究的主要方法之一是理想模型．理想模型是为便于研究而建立的一种高度抽象的理想客体，它抓住物质的主要特征，忽略次要因素，形成一种经过抽象、概括了的理想化的模型．作为科学抽象的结果，理想模型也是一种科学概念，可是，它不同于一般的科学概念，如数学上的点与物理中的质点截然不同，因此我们一定要正确理解物理学中的理想模型，把握好这一概念的思维，掌握好这一概念的思维能力，就既能使问题得到了简化，又不影响问题的本质，让问题迎刃而解．下面通过几个例题，进行具体分析：     

复杂背景下实时运动目标的提取

提出了一种结合帧间减法与背景自适应更新的算法,结合高速图像处理平台,以满足实时运动目标的提取。着眼于算法的高速性并提出一种足够快的方法用于弹道测量系统。用高斯分布建立每个像素的灰度模型,这个分布用来区分前景和背景像素以便用来更新背景模型。实验表明该系统可以满足靶场弹道测量任务实时性的要求,传统大量占用系统资源的算法在该系统中得到改善,大大提高了系统的实时性。     

动态背景下基于光流场分析的运动目标检测算法

针对现有动态背景下运动目标检测算法的不足,提出一种基于光流场分析的运动目标检测算法.首先根据前背景在光流梯度幅值和光流矢量方向上的差异确定目标的大致边界,然后通过点在多边形内部原理获得边界内部的稀疏像素点,最后以超像素为节点,利用混合高斯模型拟合的表观信息和超像素的时空邻域关系构建马尔可夫随机场模型的能量函数,并通过使目标函数能量最小化得到最终的运动目标检测结果.该算法不需要任何先验假设,能够同时处理动态背景和静态背景两种情况.多组实验结果表明,本文算法在检测的准确性和处理速度上均优于现有算法.     

From PAMELA to CDMS and back

We study implications of the recent results from the CDMS Collaboration on astrophysical probes of dark matter. By crossing symmetry an elastic scattering cross section with the nucleon implies annihilation of dark matter into hadrons inside the halo, resulting in an anti-proton flux that could be constrained by data from the PAMELA Collaboration if one includes a large boost factor necessary to explain the PAMELA excess in the positron fraction. As an illustration, we present a model-independent analysis for a fermionic dark matter and study the upper bound on the boost factor using the PAMELA anti-proton flux.     

Static and quasistatic solutions of the real Proca field

We consider the theory of the massive real vector field with spin 1 (the real Proca field) and its solutions. First the field equations with dual symmetry [1] are written and the 4-pseudo vector is chosen to be zero. The constants of motion for the real Proca field, the constant “electric” real Proca field, the uniform motion of a point charge in the real Proca field, uniform motions in the “Coulomb” field, dipole and multipole free-momentum, constant “magnetic” field, and the field of a point charge in motion are presented.     

复杂环境下运动目标偏振成像检测方法研究

针对低对比度、低信噪比等复杂环境下运动目标检测失检率较高的问题,提出了基于稳定性主成分寻踪的运动目标偏振成像检测方法。首先将预处理后的连续帧偏振图像组合成一个矩阵,依据帧间图像信息相关性,建立了稳定性主成分寻踪数学模型,将该矩阵分解成低秩、稀疏,噪声三部分,其中稀疏矩阵包含了帧间目标信息;再以低秩矩阵核范数与稀疏矩阵1范数的和为目标函数,利用增广拉格朗日乘子法求得目标函数值最小时的稀疏矩阵;最后采用马尔科夫随机场滤除稀疏矩阵中的噪声。实验结果表明,该方法对复杂环境有很好的适应能力,且检测准确率优于其他算法。     

复杂环境下运动目标偏振成像检测方法研究

针对低对比度、低信噪比等复杂环境下运动目标检测失检率较高的问题,提出了基于稳定性主成分寻踪的运动目标偏振成像检测方法。首先将预处理后的连续帧偏振图像组合成一个矩阵,依据帧间图像信息相关性,建立了稳定性主成分寻踪数学模型,将该矩阵分解成低秩、稀疏,噪声三部分,其中稀疏矩阵包含了帧间目标信息;再以低秩矩阵核范数与稀疏矩阵1范数的和为目标函数,利用增广拉格朗日乘子法求得目标函数值最小时的稀疏矩阵;最后采用马尔科夫随机场滤除稀疏矩阵中的噪声。实验结果表明,该方法对复杂环境有很好的适应能力,且检测准确率优于其他算法。     

Resolution deterioration in emission electron microscopy due to object roughness

In the present paper a general analytic expression has been obtained and confirmed by a computer simulation which links the surface roughness of an object under study in an emission electron microscope and it's resolution. A quantitative derivation was made for the model case when there is a step on the object surface. It was shown that the resolution is deteriorated asymmetrically relative to the step. The effect sets a practical limit to the ultimate lateral resolution obtainable in an emission electron microscope.     

From reciprocal space to real space in surface science

This issue is dedicated to Karl-Heinz Rieder on the occasion of his 70th birthday. It contains contributions written by his former students and colleagues from all over the world. Experimental techniques based on free electrons, such as photoelectron spectroscopy, electron microscopy and low energy electron diffraction (LEED), were foundational to surface science. While the first revealed the band structures of materials, the second provided nanometer scale imagery and the latter elucidated the atomic scale periodicity of surfaces. All required an (ultra-)high vacuum, and LEED illustrated impressively that adsorbates, such as carbon monoxide, hydrogen or oxygen, can markedly and periodically restructure surfaces from their bulk termination, even at pressures ten orders of magnitude or more below atmospheric. Yet these techniques were not generally able to reveal atomic scale surface defects, nor could they faithfully show adsorption of light atoms such as hydrogen. Although a complete atom, helium can also be regarded as a wave with a de Broglie wavelength that allows the study of surface atomic periodicities at a delicateness and sensitivity exceeding that of electrons-based techniques. In combination, these and other techniques generated insight into the periodicity of surfaces and their vibrational properties, yet were limited to simple and periodic surface setups. All that changed with the advent of scanning tunneling microscopy (STM) roughly 30 years ago, allowing real space access to surface defects and individual adsorbates. Applied at low temperatures, not only can STM establish a height profile of surfaces, but can also perform spectroscopy and serve as an actuator capable of rearranging individual species at atomic scale resolution. The direct and intuitive manner in which STM provided access as a spectator and as an actor to the atomic scale was foundational to today's surface science and to the development of the concepts of nanoscience in general. The cover image of this issue honors this achievement. It shows 27 chiral heptahelicene molecules arranged by one of the guest editors (KHE) with the very same STM at IBM Almaden Research Center, San José that was used for moving xenon atoms more than 20 years ago. Karl-Heinz Rieder's career, as briefly outlined in the biography by G Benedek in this issue, reflected this paradigm shift in surface science from reciprocal to real space investigations: initially focusing on helium scattering as a superior technique for the investigation of delicate surfaces, his group at the Freie University in Berlin became the second in the world to rearrange atoms and molecules at surfaces in a controlled way and they generated much of the foundational work of low temperature STM investigations. Besides his saxophone skills and many other hobbies, Karl-Heinz is a real poet and loves composing funny limericks and spoonerisms. He wrote the following poem (passed on to us by W-D Schneider) at the International School of Solid State Physics in 1998 in Erice, Italy. It is a real masterpiece, beautifully summarizing us all, the 'Surface Science Society'. The top atom sheetSome become real slaves is important and neat.looking at standing waves. Therefore there is a strong raceThe producers of coatings in the science of surface.get really good quotings. To clean it you needStill others use new ways ions and heat.with electrons and x-rays. Then the atoms arrangeAnd all has to be in some ways that are strange,in good UHV-except theory, they relax, reconstructwhich thinks on extensions as a matter of fact.to still lower dimensions, And reacting with gasesand with lots of computing they form quite new phasestries to get solid footing. with large unit cellsSo everybody with joy as diffraction tells.plays his own special toy. Some people use lightAnd all think they are better from a synchrotron brightshould get published a letter. and claim it is bestBut before there's more cluster to do this in Triest.let's finish-aus basta Some move atoms around to hear how they sound.Karl-Heinz Rieder, Erice, 6 April 1998 From reciprocal space to real space in surface science contents From reciprocal space to real space in surface scienceLudwig Bartels and Karl-Heinz Ernst Karl-Heinz Reider: the quiet pioneerGiorgio Benedek Scattering of CO and N(2) molecules by a graphite surfaceJunepyo Oh, Takahiro Kondo, Keitaro Arakawa, Yoshihiko Saito, Junji Nakamura, W W Hayes and J R Manson Helium, neon and argon diffraction from Ru(0001)M Minniti, C Díaz, J L Fernández Cu?ado, A Politano, D Maccariello, F Martín, D Farías and R Miranda Enhanced charge transfer in a monolayer of the organic charge transfer complex TTF-TNAP on Au(111)T R Umbach, I Fernandez-Torrente, J N Ladenthin, J I Pascual and K J Franke Extended pattern recognition scheme for self-learning kinetic Monte Carlo simulationsSyed Islamuddin Shah, Giridhar Nandipati, Abdelkader Kara and Talat S Rahman Acetylene on Cu(111): imaging a molecular surface arrangement with a constantly rearranging tipYeming Zhu, Jonathan Wyrick, Kamelia D Cohen, Katie Marie Magnone, Connor Holzke, Daniel Salib, Quan Ma, Dezheng Sun and Ludwig Bartels Coulomb attraction during the carpet growth mode of NaClFriederike Matthaei, Sarah Heidorn, Konrad Boom, Cord Bertram, Ali Safiei, J?rg Henzl and Karina Morgenstern Molecular self-assembly on an insulating surface: interplay between substrate templating and intermolecular interactionsMarkus Kittelmann, Philipp Rahe and Angelika Kühnle Vertical manipulation of native adatoms on the InAs(111)A surfaceJ Yang, C Nacci, J Martínez-Blanco, K Kanisawa and S F?lsch Charge transfer between isomer domains on n(+)-doped Si(111)-2 × 1: energetic stabilizationR M Feenstra, G Bussetti, B Bonanni, A Violante, C Goletti, P Chiaradia, M G Betti and C Mariani Probing the properties of metal-oxide interfaces: silica films on Mo and Ru supportsLeonid Lichtenstein, Markus Heyde, Stefan Ulrich, Niklas Nilius and Hans-Joachim Freund Mapping the first electronic resonances of a Cu phthalocyanine STM tunnel junctionW-H Soe, C Manzano, H S Wong and C Joachim Epitaxial Bi allotropes on quasicrystal surfaces as templates for adsorption of pentacene and fullereneH R Sharma, J A Smerdon, K M Young and R McGrath Island formation and manipulation of prochiral azobenzene derivatives on Au(111)Sofia Selvanathan, Maike V Peters, Stefan Hecht and Leonhard Grill.     

Hybrid C2 features and spectral residual approach to object recognition

To establish a fast and accurate visual object recognition system is a fundamental and formidable task. In most cases, rapidity and stability can be inconsistent. In order to solve this problem, a novel object recognition system, which is based on hybrid C2 features and saliency detection, is proposed in this paper. Spectrum residual method is introduced for fast location of object regions, and the C2 features are the main characteristic used for object distinction. After the candidate regions of possible target are extracted, the object recognition task is converted to a categorization problem, which can be solved by SVM (Support Vector Machine) classifier. To prove the feasibility and effectiveness of our system, several experiments are conducted, and the experimental results further illustrate the rapidity with high accuracy of our proposed recognition system.     

Isospin dynamics in heavy ion collisions: From Coulomb barrier to quark gluon plasma

Heavy Ion Collisions (HIC) represent a unique tool to probe the in-medium nuclear interaction in regions away from saturation. In this report, we present a selection of new reaction observables in dissipative collisions particularly sensitive to the symmetry term of the nuclear Equation of State (Iso-EoS). We will first discuss the Isospin Equilibration Dynamics. At low energies, this manifests via the recently observed Dynamical Dipole Radiation, due to a collective neutron-proton oscillation, with the symmetry term acting as a restoring force. At higher beam energies, Iso-EoS effects will be seen in Imbalance Ratio Measurements, in particular from the correlations with the total kinetic energy loss. For fragmentation reactions in central events, we suggest to look at the coupling between isospin distillation and radial flow. In Neck Fragmentation reactions, important Iso-EoS information can be obtained from the correlation between isospin content and alignment. The high density symmetry term can be probed from isospin effects on heavy ion reactions at relativistic energies (few AGeV range). Rather, isospin sensitive observables are proposed from nucleon/cluster emissions, collective flows and meson production. The possibility to shed light on the controversial neutron/proton effective mass splitting in asymmetric matter is also suggested. A large symmetry repulsion at high baryon density will also lead to an “earlier” hadron-deconfinement transition in n-rich matter. A suitable treatment of the isovector interaction in the partonic EoS appears very relevant.