3,358 research outputs found
Measurement and simulation of laser-induced fluorescence from non-equilibrium ultracold neutral plasmas
We report new measurements and simulations of laser-induced fluorescence in
ultracold neutral plasmas. We focus on the earliest times, when the plasma
equilibrium is evolving and before the plasma expands. In the simulation, the
ions interact via the Yukawa potential in a small cell with wrapped boundary
conditions. We solve the optical Bloch equation for each ion in the simulation
as a function of time. Both the simulation and experiment show the initial
Bloch vector rotation, disorder-induced heating, and coherent oscillation of
the rms ion velocity. Detailed modeling of the fluorescence signal makes it
possible to use fluorescence spectroscopy to probe ion dynamics in ultracold
and strongly coupled plasmas
Measurement and simulation of laser-induced fluorescence from non-equilibrium ultracold neutral plasmas
We report new measurements and simulations of laser-induced fluorescence in
ultracold neutral plasmas. We focus on the earliest times, when the plasma
equilibrium is evolving and before the plasma expands. In the simulation, the
ions interact via the Yukawa potential in a small cell with wrapped boundary
conditions. We solve the optical Bloch equation for each ion in the simulation
as a function of time. Both the simulation and experiment show the initial
Bloch vector rotation, disorder-induced heating, and coherent oscillation of
the rms ion velocity. Detailed modeling of the fluorescence signal makes it
possible to use fluorescence spectroscopy to probe ion dynamics in ultracold
and strongly coupled plasmas
Notes on implementation of sparsely distributed memory
The Sparsely Distributed Memory (SDM) developed by Kanerva is an unconventional memory design with very interesting and desirable properties. The memory works in a manner that is closely related to modern theories of human memory. The SDM model is discussed in terms of its implementation in hardware. Two appendices discuss the unconventional approaches of the SDM: Appendix A treats a resistive circuit for fast, parallel address decoding; and Appendix B treats a systolic array for high throughput read and write operations
CrossComp: Comparing Multiple Artists Performing Similar Modeling Tasks
In two previous papers, we have focused on summarizing and visualizing the edits of a single workflow and visualizing and merging the edits of two independent workflows. In this paper, we focus on visualizing the similarities and dissimilarities of many workflows where digital artists perform similar tasks. The tasks have been chosen so each artist starts and ends with a common state. We show how to leverage the previous work to produce a visualization tool that allows for easy scanning through the workflows
MeshGit: Diffing and Merging Polygonal Meshes
This paper presents MeshGit, a practical algorithm for diffing and merging polygonal meshes. Inspired by version control for text editing, we introduce the mesh edit distance as a measure of the dissimilarity between meshes. This distance is defined as the minimum cost of matching the vertices and faces of one mesh to those of another. We propose an iterative greedy algorithm to approximate the mesh edit distance, which scales well with model complexity, providing a practical solution to our problem. We translate the mesh correspondence into a set of mesh editing operations that transforms the first mesh into the second. The editing operations can be displayed directly to provide a meaningful visual difference between meshes. For merging, we compute the difference between two versions and their common ancestor, as sets of editing operations. We robustly detect conflicting operations, automatically apply non-conflicting edits, and allow the user to choose how to merge the conflicting edits. We evaluate MeshGit by diffing and merging a variety of meshes and find it to work well for all
3DFlow: Continuous Summarization of Mesh Editing Workflows
Mesh editing software is continually improving allowing more detailed meshes to be create efficiently by skilled artists. Many of these are interested in sharing not only the final mesh, but also their whole workflows both for creating tutorials as well as for showcasing the artist\u27s talent, style, and expertise. Unfortunately, while creating meshes is improving quickly, sharing editing workflows remains cumbersome since time-lapsed or sped-up videos remain the most common medium. In this paper, we present 3DFlow, an algorithm that computes continuous summarizations of mesh editing workflows. 3DFlow takes as input a sequence of meshes and outputs a visualization of the workflow summarized at any level of detail. The output is enhanced by highlighting edited regions and, if provided, overlaying visual annotations to indicated the artist\u27s work, e.g. summarizing brush strokes in sculpting. We tested 3DFlow with a large set of inputs using a variety of mesh editing techniques, from digital sculpting to low-poly modeling, and found 3DFlow performed well for all. Furthermore, 3DFlow is independent of the modeling software used since it requires only mesh snapshots, using additional information only for optional overlays. We open source 3DFlow for artists to showcase their work and release all our datasets so other researchers can improve upon our work
New and emerging treatments for fungal infections
Although several new antifungal drugs have been licensed in the last 5 years, some patients remain difficult to treat. The main reasons for this include intrinsic or acquired antifungal resistance, organ dysfunction preventing the use of some agents and drug interactions. In addition, some drugs pene-trate poorly into sanctuary sites including eye and urine, and others are associated with considerable adverse events. Here, we review the preclinical and clinical development progress with four new anti-fungal agents: isavuconazole, ravuconazole, albaconazole and aminocandin. Isavuconazole and ravu-conazole are extremely similar, with a broad spectrum of activity, a very long half-life and large volume of distribution and good in vivo data supporting their efficacy in invasive aspergillosis and candidosis. Both compounds are in early Phase 3 development. Albaconazole has also shown very potent activity against species of Candida, Cryptococcus and Aspergillus. It was well tolerated and effective in women with vaginal candidosis. Aminocandin is an intravenous-only echinocandin with in vivo activity against Candida spp. and Aspergillus spp. Its extended half-life probably permits dosing less fre-quently than once a day. Overall these new antifungal agents in development offer extended half-lives, possibly reduced drug interaction profiles and good tolerance. Their antifungal spectrum is narrower than posaconazole and probably similar to voriconazole (isavuconazole and ravuconazole) and caspo-fungin (aminocandin). Licensure and determination of their place in clinical practice requires random-ized clinical studies, which are or will be underway
American Insurance Association v. Garamendi and Executive Preemption in Foreign Affairs
In American Insurance Association v. Garamendi, the U.S. Supreme Court invalidated California\u27s Holocaust Victim Insurance Relief Act (HVIRA), which required insurance companies doing business in California to disclose all policies they or their affiliates sold in Europe between 1920 and 1945. According to the Court, the state\u27s law unconstitutionally interfered with the foreign affairs power of the national government. The decision was easily overlooked in a Term filled with landmark cases dealing with affirmative action and sexual privacy. What coverage the case did receive emphasized its federalism aspects, and excited little reaction because the result seemed intuitively appropriate given the federal government\u27s interest in conducting foreign affairs.
We argue in this paper, however, that Garamendi is more important - and problematic - when seen as a case about separation of powers. In particular, we argue that the decision expands presidential control over foreign affairs, not only at the expense of the states, but also and more critically at the expense of Congress and the Senate. This arises from the Court\u27s invention of a novel constitutional power of executive preemption - that is, an independent ability of the President to override state laws that interfere with executive branch policies in foreign affairs. Until Garamendi, no one had thought that a mere executive branch policy, unsupported by the formal or even tacit approval of any other branch, could have the effect of preemptive law.
As a result, one need not be a defender of foreign policy federalism, nor a critic of executive foreign affairs powers, to have grave reservations about the decision\u27s implications for separation of powers, federalism and constitutional theory. It is uncontroversial that state laws and policies must give way to the foreign affairs objectives of the national government. The critical question, though, is how these overriding federal goals are developed and identified. We argue that the Garamendi decision has at least three separate and substantial ill-effects upon this process.
First,executive preemption conveys to the President the power to decide which state laws affecting foreign affairs survive and which do not. This concentrates foreign affairs power in the President in a way not contemplated by the Constitution\u27s Framers, who sought to separate executive power from legislative power. Second, Garamendi seemed to make executive agreements the functional equivalents of congressional statutes; this functional equivalency may hasten the decline of the treaty as a foreign policy-making tool, with a concomitant decline in the opportunities for Congress - the Senate, in particular - to shape foreign policy. Third, the decision implicated the relationship between the states and the federal government in foreign affairs, but did so in a way that provided essentially no guidance for the future.
Part I of this Article discusses the factual setting of the Holocaust insurance claims that formed the background of the case. Part II outlines the constitutional law of federal-state relations in foreign affairs as it stood before the Garamendi decision. Part III describes the Supreme Court\u27s decision, and points out its discontinuity with prior decisions. In Part IV we turn to the troubling structural implications of Garamendi, which we regard as occurring primarily in the field of separation of powers. We conclude that the Court ended up far from the text, structure and history of the Constitution. In Part V we address the decision\u27s implications for federalism, particular the dangers of concentrating preemptive power in the executive branch.
Part VI relates the Garamendi case to the wider theoretical debates of modern foreign affairs law and constitutional interpretation. In contrast to other federalism and separation of powers cases, the Garamendi Court paid little attention to text or structure in analyzing the constitutional questions presented. More surprising, perhaps, is the Court\u27s complete lack of interest in what light history might shed on the foreign affairs issues before it. But neither is Garamendi an exercise in common law doctrinal evolution, because it owes essentially nothing to prior cases or practice, except as rhetorical cover. Garamendi\u27s near-exclusive attention to loose interpretations of prior case law and its lack of sensitivity to text, history, and structure, suggest to us a danger in common law constitutional interpretation as a preferred approach to constitutional interpretation and adjudication in foreign affairs controversies
Detecting control flow in Smarphones: Combining static and dynamic analyses
International audienceSecurity in embedded systems such as smartphones requires protection of confidential data and applications. Many of security mechanisms use dynamic taint analysis techniques for tracking information flow in software. But these techniques cannot detect control flows that use conditionals to implicitly transfer information from objects to other objects. In particular, malicious applications can bypass Android system and get privacy sensitive information through control flows. We propose an enhancement of dynamic taint analysis that propagates taint along control dependencies by using the static analysis in embedded system such as Google Android operating system. By using this new approach, it becomes possible to protect sensitive information and detect most types of software exploits without reporting too many false positives
- …