Development and Validation of NDE Standards for NASAs Advanced Composites Project

The adoption of composite materials in aircraft manufacturing for use in structural applications continues to increase but is still relatively new to the industry. Composite components have large development and certification costs in comparison to metallic structures. Traditional methods of nondestructive evaluation (NDE) used for isotropic materials such as metals may not be adequate for composite applications and therefore is a contributing factor to the cost and complexity of developing new structural composites. Additionally, the defects of interest in composite materials are significantly different from metals. Thus, good quality composite reference standards are essential to obtaining reliable and quantifiable NDE results. Ideally, reference standards contain flaws or damage whose NDE indications most closely represent those created by actual flaws/damage. They should also be easy to duplicate and inexpensive to manufacture. NASAs Advanced Composites Project, working with industry partners, developed a set of composite standards that contain a range of validated defects representing those typically found in aerospace composite materials. This paper will provide an overview of the standards fabricated, the manufacturing plans used to fabricate them, the types of defects included, and validation testing that has performed. Also discussed is an inter-laboratory round-robin test that is being performed on these standards. The paper will describe a guidance document being compiled to outline relevant inspection procedures for challenging and critical defects unique to composites where conventional techniques may not be appropriate

Parametric instabilities in magnetized multicomponent plasmas

This paper investigates the excitation of various natural modes in a magnetized bi-ion or dusty plasma. The excitation is provided by parametrically pumping the magnetic field. Here two ion-like species are allowed to be fully mobile. This generalizes our previous work where the second heavy species was taken to be stationary. Their collection of charge from the background neutral plasma modifies the dispersion properties of the pump and excited waves. The introduction of an extra mobile species adds extra modes to both these types of waves. We firstly investigate the pump wave in detail, in the case where the background magnetic field is perpendicular to the direction of propagation of the pump wave. Then we derive the dispersion equation relating the pump to the excited wave for modes propagating parallel to the background magnetic field. It is found that there are a total of twelve resonant interactions allowed, whose various growth rates are calculated and discussed.Comment: Published in May 2004; this is a late submission to the archive. 14 pages, 8 figure

On the possibility of an astronomical detection of chromaticity effects in microlensing by wormhole-like objects

We study the colour changes induced by blending in a wormhole-like microlensing scenario with extended sources. The results are compared with those obtained for limb darkening. We assess the possibility of an actual detection of the colour curve using the difference image analysis method.Comment: Accepted for publication in Modern Physics Letters A. 13 report pages, 7 figure

Chromaticity effects in microlensing by wormholes

Chromaticity effects introduced by the finite source size in microlensing events by presumed natural wormholes are studied. It is shown that these effects provide a specific signature that allow to discriminate between ordinary and negative mass lenses through the spectral analysis of the microlensing events. Both galactic and extragalactic situations are discussed.Comment: To appear in Modern Physics Letters A, 200

Constructing Alternative Avenues of Jurisdictional Protection: Bypassing Burnham\u27s Roadblock Via § 1404(a)

A plaintiff from Maine sues an insurance company, incorporated in Maine and having its principal place of business in Maine, on a loss incurred in Maine under a contract negotiated, written, and executed in Maine. The plaintiff files the suit in Alabama to take advantage of its liability law, its statute of limitations, its juries, its rules of evidence, and its posture toward plaintiffs. The plaintiff serves a representative of the insurance company traveling in Alabama en route to an industry convention. For all the reasons the plaintiff seeks a forum in Alabama, the defendant wishes to avoid that forum. The importance of forum and the judicial tools available to ensure that the most appropriate forum adjudicates disputes are the subjects of this Note. Prior to Burnham v. Superior Court of California,\u27 a defendant could successfully claim that Alabama\u27s assertion of general jurisdiction should be determined under the constitutional fundamental fairness doctrine developed in the International Shoe Co. v. Washington and Rush v. Savchuk\u27 line of cases. The defendant would explain the regulatory nature of jurisdiction. The defendant would ask the trial court to hold that Alabama\u27s assertion of jurisdiction violates the defendant\u27s due process rights because Alabama lacks a regulatory interest in adjudicating the dispute. The defendant would illustrate Maine\u27s regulatory interests in adjudicating the meaning of contracts, setting policies, and protecting parties whose conduct occurred within its borders. Burnham, with its appeal to tradition and black letter Aristotelian principles, closed this avenue of protection.! It held that a forum\u27s assertion of general jurisdiction based on physical presence unrelated to the cause of action was per se constitutional. Defendants must now seek alternative routes to ensure that the most appropriate forum imposes its regulatory regime on the underlying dispute. In the wake of Burnham, a small handful of scholars predicted that forum non conveniens doctrine and the Federal Transfer Statute, 28 U.S.C. § 1404(a), might become that avenue by allowing trial courts to re- insert fundamental fairness into jurisdiction determinations. This Note illustrates that ? 1404(a) accomplishes this task, although judges and the legal community may not always realize that this is occurring. Part II explains why forum matters. It examines the phenomenon of forum-shopping and the underlying reasons why plaintiffs (and defendants) favor some fora over others. The Part argues that the selection of a forum embodies more than simply choosing a physical location. The selection signifies the imposition of an entire regulatory regime. This Part illustrates how forum, more than anything else, affects the distribution and adjudication of justice in this country. Part III explores the evolution of constitutional jurisdictional principles that came to recognize the importance of forum. By focusing on International Shoe and its progeny, the section traces the development of constitutional fundamental fairness safeguards against a forum\u27s assertion of general jurisdiction. It explains that when the Supreme Court applied the fundamental fairness doctrine, it was really concerned with the imposition of a regulatory regime. The Court made ad hoc value judgments concerning the appropriateness of a forum\u27s regulatory regime. Subsequent developments in jurisdictional jurisprudence appeared to incorporate fundamental fairness into general jurisdiction, thereby ensuring that only those forums with regulatory interests will adjudicate particular disputes. Part IV shows how Burnham v. Superior Court closed this avenue of constitutional protection. It examines how the Supreme Court\u27s decision in Burnham foreclosed further application of the fundamental fairness doctrine developed in the International Shoe line of cases to determinations of the constitutionality of general jurisdiction. This Part addresses the criticism and the black letter basis of the decision. Part V proposes an alternative to Burnham. It traces the development, purpose, and application of the common law doctrine of forum non conveniens. The Part explores the Supreme Court\u27s decision in Gulf Oil Corp. v. Gilbert, in which the Court borrowed heavily from the fundamental fairness standard of International Shoe. Gulf Oil incorporated the notion of forum as regulatory regime into forum non conveniens determinations. Part VI begins the discussion of the Federal Transfer Statute, 28 U.S.C. § 1404. It explains the statute\u27s purpose, legislative history, use, and application in the federal judiciary. The Part illustrates how district courts, in their application of § 1404, have developed numerous factors that go beyond mere convenience to ascertain the appropriateness of transfer. Part VII looks beyond the rhetoric of convenience and concentrates on the many factors that district courts use in deciding § 1404(a) motions. The Part reveals that some trial judges actually conduct a fundamental fairness analysis to impose the proper regulatory regime. It notes that most scholars have expressed disdain at the plethora of factors and have described the entire § 1404(a) jurisprudence as one marked by chaos and inconsistency. These scholars fail to realize that § 1404(a) is accomplishing what the Supreme Court attempted to frustrate in Burnham: the use of ad hoc value judgments under the auspices of fundamental fairness to select the proper forum for a cause of action. Finally, Part VIII examines the obstacles that may prevent § 1404(a) from actually carrying out the goals of fundamental fairness. It questions the Supreme Court\u27s decisions in Van Dusen v. Barrack\u27 and Ferens v. John Deere Co. The Part provides alternatives and exceptions to the rules developed by those cases. It also answers those who argue that the lack of appellate review of § 1404(a) motions pres- ents a major problem. This Part explains that while these concerns are understandable, they are rooted in appeals to black letter rules and undervalue the need for trial judge discretion to make determinations on a case-by-case basis. Finally, it will advise against seduction by black letter rhetoric and support the ad hoc, case-by-case approach used presently, though surreptitiously, by trial judges

Handbook for estimating toxic fuel hazards

Computer program predicts, from readily available meteorological data, concentration and dosage fields downwind from ground-level and elevated sources of toxic fuel emissions. Mathematical model is applicable to hot plume rise from industrial stacks and should also be of interest to air pollution meteorologists

DNA photodamage recognition by RNA polymerase II.

During gene transcription, RNA polymerase (Pol) II encounters obstacles, including lesions in the DNA template. Here, we review a recent structure–function analysis of Pol II transcribing DNA with a bulky photo-lesion in the template strand. The study provided the molecular basis for recognition of a damaged DNA by Pol II, which is the first step in transcription-coupled DNA repair (TCR). The results have general implications for damage recognition and the TCR mechanism.http://dx.doi.org

Diagnostic criteria for grading the severity of acute motion sickness

Diagnostic criteria for grading severity of acute motion sicknes