Computer Algebra Solving of Second Order ODEs Using Symmetry Methods

An update of the ODEtools Maple package, for the analytical solving of 1st and 2nd order ODEs using Lie group symmetry methods, is presented. The set of routines includes an ODE-solver and user-level commands realizing most of the relevant steps of the symmetry scheme. The package also includes commands for testing the returned results, and for classifying 1st and 2nd order ODEs.Comment: 24 pages, LaTeX, Soft-package (On-Line help) and sample MapleV sessions available at: http://dft.if.uerj.br/odetools.htm or http://lie.uwaterloo.ca/odetools.ht

The Professional Responsibility Case for Valid and Nondiscriminatory Bar Exams

Title VII protects against workplace discrimination in part through the scrutiny of employment tests whose results differ based on race, gender, or ethnicity. Such tests are said to have a disparate impact, and their use is illegal unless their validity can be established. Validity means that the test is job-related and measures what it purports to measure. Further, under Title VII, even a valid employment test with a disparate impact could be struck down if less discriminatory alternatives exist.Licensing tests, including bar exams, have been found to be outside these Title VII protections. But the nondiscrimination values that animate Title VII disparate impact analysis for employers apply just as fundamentally to attorney licensing through principles of professional responsibility and legal ethics.This Article examines the civil rights cases from the 1970s that established bar examiners’ immunity from Title VII. It then analyzes our professional duties of public protection, competence, and nondiscrimination that require valid, nondiscriminatory attorney licensing tests, suggesting that the Title VII framework be borrowed for this purpose. The Article then undertakes that scrutiny, presenting evidence of the disparate impact of bar exams and their unproven validity, and suggesting feasible, less discriminatory modifications and alternatives. In other words, core professional responsibilities require consideration and adoption of valid licensing mechanisms that can reduce any disparate impact in who we permit to enter our profession, and who we exclude

Tractability of Theory Patching

In this paper we consider the problem of `theory patching', in which we are given a domain theory, some of whose components are indicated to be possibly flawed, and a set of labeled training examples for the domain concept. The theory patching problem is to revise only the indicated components of the theory, such that the resulting theory correctly classifies all the training examples. Theory patching is thus a type of theory revision in which revisions are made to individual components of the theory. Our concern in this paper is to determine for which classes of logical domain theories the theory patching problem is tractable. We consider both propositional and first-order domain theories, and show that the theory patching problem is equivalent to that of determining what information contained in a theory is `stable' regardless of what revisions might be performed to the theory. We show that determining stability is tractable if the input theory satisfies two conditions: that revisions to each theory component have monotonic effects on the classification of examples, and that theory components act independently in the classification of examples in the theory. We also show how the concepts introduced can be used to determine the soundness and completeness of particular theory patching algorithms.Comment: See http://www.jair.org/ for any accompanying file

Using Layer of Protection Analysis (LOPA) to Determine Safety Integrity Level (SIL) for Hazardous Installation

The purpose of this project is to determine the Safety Integrity Levels (SIL) for hazardous installation by using the risk assessment techniques. Various methods can be used in determining this SIL. The selected method is based on the certain criteria. The method will be used for the whole project as the based techniques to defined SIL. In this case, Layer of Protection Analysis (LOPA) has been chosen as the risk-based approach to evaluate potential consequences and likelihood. Many factors could be considered in order to complete this project. The selection of SIL is very important since in many cases the Safety Instrumented System (SIS) is the last layer of protection for the prevention of hazardous events. The safety integrity of the safety functions to be implemented in the SIS is to be identified in terms of Safety Integrity levels (SILs). Each SIL is assigned with a specific range of Probability to Fail on Demand (PFD). In this project, current industry practices for the selection of SILs are evaluated to illustrate how each method provides an estimation risk of risk reduction that the SIS will provide for a given process. The level of effort, required expertise, and accuracy of the methods are also compared to assist reader in choosing the appropriate SIL selection methodology. LOPA method will be applied as some related data and tools should be collected in ensuring the successfulness of the project

A War of Words: The Circulation and Interpretation of Taiping Depositions

On November 18, 1864, the death knell of the Taiping Heavenly Kingdom was rung. Hong Tiangui Fu had been killed. Hong, divine leader of the once nascent kingdom, was asked to confess before his execution, one of the last figures to speak directly on behalf of the Qing’s formidable opponent. The Western world listened intently to the Young Monarch’s last words, curious about the movement’s unorthodox Christianity and the destruction they had left behind. The deposition resulting from Hong’s confession fit within an established legal genre. Depositions had long been collected to indict members of oppositional movements, as well as provide officials with a more comprehensive understanding of resistance. Hong’s deposition circulated well beyond archives and into the hands of foreign publications. Commentators eagerly translated and edited the document, placing their interpretations at the core of foreign debate about the conflict’s legitimacy. This thesis changes our understanding of the process through which Taiping depositions were created and utilized. Challenging previous assumptions that approached these documents as mere tools for factual reconstruction, this work argues that court depositions played a vital role in shaping contemporary perceptions of Qing rule and of its opposition movements. Previous discussions on Taiping depositions are frozen in colonial and Cold War narratives, as those debating their value fail to understand that depositions were products of personal and communal ambitions. Authors perceive these documents as static indicators of the movement’s character, used to legitimize or damage the narrative deployed by their respective political alignment. By analyzing the depositions written by Taiping leaders, in addition to any subsequent edits or reactions surrounding them, this thesis examines the role depositions played in determining external perceptions of the Taiping. In following the lifespan of these documents, as opposed to judging their character, a greater understanding of their impact is revealed

Reliability improvement of electronic circuits based on physical failure mechanisms in components

Traditionally the position of reliability analysis in the design and production process of electronic circuits is a position of reliability verification. A completed design is checked on reliability aspects and either rejected or accepted for production. This paper describes a method to model physical failure mechanisms within components in such a way that they can be used for reliability optimization, not after, but during the early phase of the design process. Furthermore a prototype of a CAD software tool is described, which can highlight components likely to fail and automatically adjust circuit parameters to improve product reliability

The end of the waterfall: Default resources of central counterparties

Central counterparties (CCPs) have become pillars of the new global financial architecture following the financial crisis of 2008. The key role of CCPs in mitigating counterparty risk and contagion has in turn cast them as systemically important financial institutions whose eventual failure may lead to potentially serious consequences for financial stability, and prompted discussions on CCP risk management standards and safeguards for recovery and resolutions of CCPs in case of failure. We contribute to the debate on CCP default resources by focusing on the incentives generated by the CCP loss allocation rules for the CCP and its members and discussing how the design of loss allocation rules may be used to align these incentives in favor of outcomes which benefit financial stability. After reviewing the ingredients of the CCP loss waterfall and various proposals for loss recovery provisions for CCPs, we examine the risk management incentives created by different ingredients in the loss waterfall and discuss possible approaches for validating the design of the waterfall. We emphasize the importance of CCP stress tests and argue that such stress tests need to account for the interconnectedness of CCPs through common members and cross-margin agreements. A key proposal is that capital charges on assets held against CCP Default Funds should depend on the quality of the risk management of the CCP, as assessed through independent stress tests