Origin of synchronized traffic flow on highways and its dynamic phase transitions

We study the traffic flow on a highway with ramps through numerical simulations of a hydrodynamic traffic flow model. It is found that the presence of the external vehicle flux through ramps generates a new state of recurring humps (RH). This novel dynamic state is characterized by temporal oscillations of the vehicle density and velocity which are localized near ramps, and found to be the origin of the synchronized traffic flow reported recently [PRL 79, 4030 (1997)]. We also argue that the dynamic phase transitions between the free flow and the RH state can be interpreted as a subcritical Hopf bifurcation.Comment: 4 pages, source TeX file and 4 figures are tarred and compressed via uufile

An agent-based dynamic information network for supply chain management

One of the main research issues in supply chain management is to improve the global efficiency of supply chains. However, the improvement efforts often fail because supply chains are complex, are subject to frequent changes, and collaboration and information sharing in the supply chains are often infeasible. This paper presents a practical collaboration framework for supply chain management wherein multi-agent systems form dynamic information networks and coordinate their production and order planning according to synchronized estimation of market demands. In the framework, agents employ an iterative relaxation contract net protocol to find the most desirable suppliers by using data envelopment analysis. Furthermore, the chain of buyers and suppliers, from the end markets to raw material suppliers, form dynamic information networks for synchronized planning. This paper presents an agent-based dynamic information network for supply chain management and discusses the associated pros and cons

QCD Sum Rule for S_{11}(1535)

We propose a new interpolating field for S$_{11}$(1535) to determine its mass from QCD sum rules. In the nonrelativistic limit, this interpolating field dominantly reduces to two quarks in the s-wave state and one quark in the p-wave state. An optimization procedure, which makes use of a duality relation, yields the interpolating field which overlaps strongly with the negative-parity baryon and at the same time does not couple at all to the low lying positive-parity baryon. Using this interpolating field and applying the conventional QCD sum rule analysis, we find that the mass of S$_{11}$ is reasonably close to the experimentally known value, even though the precise determination depends on the poorly known quark-gluon condensate. Hence our interpolating field can be used to investigate the spectral properties of S$_{11}$(1535).Comment: 12 pages, Revtex, 1 ps figure available from author

New York’s School Teachers Say No to the Status Quo! A Chronicle of New York State’s Teachers Union’s (NYSUT) First Contested Election

Other than a scattered mentioning on educational blogs, and a few uninspired national references, the New York State United Teacher’s (NYSUT) April 2014 first contested election in its four decade history did not seem to matter very much. We saw it differently at Cornell’s ILR School. NYSUT is known as a highly efficient, top down, union powerhouse, yet we learned that this election saw school teachers and their local union leaders utilizing their organization’s design and structure for the members’ advantage in a stunning “bottom up” political victory. This surprising outcome is why we decided to research how this occurred and write this report. Along the way, we met brilliant strategists, courageous political novitiates, remarkable communication specialists, and never-ending tenacity wrapped in purposefulness that ensured school-based leaders their electoral success. In doing so, they joined their insurgent teacher colleagues in Massachusetts, Milwaukee, Chicago, Los Angeles, St. Paul and elsewhere, affirming that school teacher trade unionists can and will respond to the attacks upon them and public education. The following pages chart why this contested election occurred and how the insurgents proceeded. The information is based primarily upon extensive interviews with rank and file leaders and discussions with former and newly elected leaders. There are also specific references to observations shared by the defeated President, Richard Iannuzzi, who graciously offered his candor in explaining how he saw what was happening to the union and why he acted as he did in the period leading up to his defeat. This report begins with some brief comments about NYSUT’s history, placement of the election in both a national and New York state context, and an explanation about how NYSUT’s structure had so much to do with the election. The bulk of the writing describes how rank and file forces slowly but molecularly developed into a force able to successfully challenge the president and leadership team of the largest state union in America. Throughout, the detail presented suggests that power wielded by rank and file union members of the teaching profession is the best hope to restore balance to public education in the country. The next few years will tell us whether this “suggestion” is so

The Three Lives of the Alien Tort Statute: The Evolving Role of the Judiciary in U.S. Foreign Relations

This Article explains how the Alien Tort Statute (ATS) began in the late eighteenth century as a national security statute that the First Congress and early federal district judges saw as a way to afford damages remedies to British merchants, creditors, and other subjects whose persons or property were injured under circumstances in which treaties or the law of nations assigned responsibility to the United States. Torts committed within the United States by private American citizens were the most likely such circumstances. The ultimate aims of the statute were to avoid renewed war with Great Britain and the other European powers and to encourage commerce and trade with the same. Two centuries later, the ATS was reborn as an international human rights statute at a time when the United States had become a global superpower with a global human-rights agenda during the administration of President Jimmy Carter. Now that the Supreme Court\u27s holding in Kiobel v. Royal Dutch Petroleum Co. has undermined the international human rights vision of the ATS, this Article suggests that the statute be used once again as a way to afford aliens money damages when they suffer torts under circumstances where the United States bears sovereign responsibility under contemporaneous international law