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Identifying and measuring the "localization length'' in many-body systems in the vicinity of a many-body localization transition is difficult. Following Hatano and Nelson, a recent work (Heuben, White, Refael, PRB 103, 064201 (2021)) introduced an "imaginary vector potential'' to a disordered ring of interacting fermions, in order to define a many-body localization length (corresponding, in the non-interacting case, to the end-to-end Green's function of the hermitian system). We extend these results, by connecting this localization length to the length scale appearing in the avalanche model of delocalization. We use this connection to derive the distribution of the localization length at the MBL transition, finding good agreement with our numerical observations. Our results demonstrate how a localization length defined as such probes the localization of the underlying ring, without the need to explicitly construct the l-bits., Comment: 24 pages (12 main text + 12 appendices/references), 21 Figures. v2 contains minor updates to Figures and added discussion of single vs multi l-bit flips. Submitted to Phys Rev B

WellNurse is a holistic, interdisciplinary, multidimensional longitudinal research study that examines evidence-based interventions intended to reduce burnout and increase resilience among graduate and undergraduate nursing students at a public university in the northeastern United States.

All-optical helicity-dependent switching in ferromagnetic layers has revealed an unprecedented route to manipulate magnetic configurations by circularly polarized femtosecond laser pulses. In this work, rare-earth free synthetic ferrimagnetic heterostructures made from two antiferromagnetically exchange coupled ferromagnetic layers are studied. Experimental results, supported by numerical simulations, show that the designed structures enable all-optical switching which is controlled, not only by light helicity, but also by the relative Curie temperature of each ferromagnetic layer. Indeed, through the antiferromagnetic exchange coupling, the layer with the larger Curie temperature determines the final orientation of the other layer and so the synthetic ferrimagnet. For similar Curie temperatures, helicity-independent back switching is observed and the final magnetic configuration is solely determined by the initial magnetic state. This demonstration of electrically-detected, optical control of engineered rare-earth free heterostructures opens a novel route toward practical opto-spintronics.

At first glance, amidst contemporary popular suspicion of the law’s onerous safeguards in favour of the accused, it may appear surreal, quixotic or even wilfully provocative to split hairs over the presentation of DNA evidence in criminal trials — particularly in cases, as below, in which all parties accept the expression of that evidence as mathematically correct and, in its own right, highly persuasive. Yet the clash of established behavioural science with uniform Australian evidence legislation and traditional expectations of jurors gives rise to questions which strike at the heart of the values of criminal law. In Aytugrul v The Queen (2012) 247 CLR 170, the High Court declined the appellant’s invitation to delve into psychological research on the effects of the ‘exclusion percentage’ on a juror’s subconscious mind. Dubious from the outset about the distinction between two alternative expressions of the same mathematical value, the Court found that the ‘exclusion percentage’ was not unfairly prejudicial as it was mitigated by prosecutorial and judicial explanation. Above all, the ‘exclusion percentage’ was salvaged by its presentation alongside the less problematic ‘ frequency ratio’. However, even if the exclusion percentage adds no further probative value beyond the ‘ frequency ratio’, the High Court preferred to analyse its merit on its own terms, in isolation. This case note draws on Heydon J’s discussion of a contrasting American decision, wide-ranging empirical studies and the policy of the law of evidence to argue that DNA evidence communicated as an ‘exclusion percentage’ should be excluded from criminal trials.

This report contains the proceedings from the First International Workshop on Reengineering Towards Product Lines (R2PL) 2005, which was held on November 10th, 2005 in Pittsburgh, Pennsylvania, USA and colocated with the Working Conference on Reverse Engineering (WCRE) 2005 and WICSA 2005, the Working Institute of Electrical and Electronics Engineers/International Federation for Information Processing (IEEE/IFIP) Conference on Software Architecture. This report consists of an overview of an invited presentation, a set of position papers, and details of the workshop's outcomes.

[Background:] Software effort prediction methods and models typically assume positive correlation between software product complexity and development effort. However, conflicting observations, i.e. negative correlation between product complexity and actual effort, have been witnessed from our experience with the COCOMO81 dataset. [Aim:] Given our doubt about whether the observed phenomenon is a coincidence, this study tries to investigate if an increase in product complexity can result in the abovementioned counter-intuitive trend in software development projects. [Method:] A modified association rule mining approach is applied to the transformed COCOMO81 dataset. To reduce noise of analysis, this approach uses a constant antecedent (Complexity increases while Effort decreases) to mine potential consequents with pruning. [Results:] The experiment has respectively mined four, five, and seven association rules from the general, embedded, and organic projects data. The consequents of the mined rules suggested two main aspects, namely human capability and product scale, to be particularly concerned in this study. [Conclusions:] The negative correlation between complexity and effort is not a coincidence under particular conditions. In a software project, interactions between product complexity and other factors, such as Programmer Capability and Analyst Capability, can inevitably play a "friction" role in weakening the practical influences of product complexity on actual development effort.

peer-reviewed This report describes the Service-Oriented Migration and Reuse Technique (SMART). SMART is a technique that helps organizations analyze legacy systems to determine whether their functionality, or subsets of it, can be reasonably exposed as services in a Service- Oriented Architecture (SOA), and thus to achieve greater interoperability. Converting legacy components to services allows systems to remain largely unchanged while exposing functionality to a large number of clients through well-defined service interfaces. A number of organizations are adopting this approach by defining SOAs that include a set of infrastructure common services on which organizations can build additional domain services or applications. SMART considers the specific interactions that will be required by the target SOA and any changes that must be made to the legacy components. An early version of SMART was applied with good success to assist a DoD organization in evaluating the potential for converting components of an existing system into services that would run in a new and tightly constrained SOA environment.

This report examines the relationship between service-oriented architectures (SOAs) and quality attributes. Because software architecture is the bridge between mission/business goals and a software-intensive system, and quality attribute requirements drive software architecture design, it is important to understand how SOAs support these requirements. This report gives a short introduction to SOAs and outlines some of the main business goals that may lead an organization to choose an SOA to design and implement a system. This report outlines a set of quality attributes that may be derived from an organization's business goals and examines how those attributes relate to an SOA. In addition, this report describes how the SOA impacts those attributes and how choosing an SOA can help an organization achieve its business goals.

Each year, the Software Engineering Institute (SEI) undertakes several Independent Research and Development (IR&D) projects. These projects serve to (1) support feasibility studies investigating whether further work by the SEI would be of potential benefit, and (2) support further exploratory work to determine whether there is sufficient value in eventually funding the feasibility study work as an SEI initiative. Projects are chosen based on their potential to mature and/or transition software engineering practices, develop information that will help in deciding whether further work is worth funding, and set new directions for SEI work. This report describes the IR&D projects that were conducted during fiscal year 2004 (October 2003 through September 2004). In addition, this report provides information on what the SEI has learned in its role as a technology scout for developments over the past year in the field of software engineering.

The Architecture Tradeoff Analysis Initiative at the Carnegie Mellon Software Engineering Institute (SEI) has developed a number of architecture-centric methods currently in use including the SEI Architecture Tradeoff Analysis Method (ATAM), the SEI Quality Attribute Workshop (QAW), the SEI Cost Benefit Analysis Method (CBAM), SEI Active Reviews for Intermediate Designs (ARID), and the SEI Attribute-Driven Design (ADD) method. Building on our success in developing and piloting a collection of software architecture methods, we're now focusing on integrating them, and building the bridges between them and the processes and architecture efforts outside the SEI, all the while continuing to refine existing methods and models. This technical note reports on a proposal to integrate the SEI ATAM and SEI CBAM. The ATAM provides software architects with a framework for understanding the technical tradeoffs and risks they face as they make design decisions, but it does not provide any guidance for understanding economic tradeoffs. The CBAM helps software architects consider the return on investment of any architectural decision and provides guidance on the economic tradeoffs involved. The CBAM takes the architectural decision analysis done during the ATAM and helps make it part of a strategic roadmap for software design and evolution by associating priorities, costs, and benefits with architectural decisions.

Because most organizations have a substantial legacy base of existing software assets, few development efforts start from scratch. However, there has not been a systematic way to identify components for reuse or to understand the types of changes that would be required for insertion into a software product line architecture or a new software architecture. Options Analysis for Reengineering (OAR) is an approach for making decisions on mining software assets. Mining involves rehabilitating parts of an old system for use in a new system. OAR identifies potential reusable components and analyzes the changes that would be needed to rehabilitate them for reuse within a software product line or new software architecture. OAR also provides an analysis of mining options, as well as the cost, effort, level of difficulty, and risks associated with each option. Recently, OAR has been applied to help a lead system integrator (LSI) make effective decisions on reuse. An LSI is the agent for an organization that is responsible for acquiring a large software-intensive system or system of systems. This note describes the use of OAR to guide decision making on mining assets within an LSI context, referred to as LSI OAR.

This report outlines an architecture reconstruction carried out at the Software Engineering Institute (SEI) on a software system called VANISH that was developed for prototyping visualizations. The goals of the reconstruction were to understand the existing VANISH system and to use a new architecture reconstruction tool, called ARMIN, for the reconstruction, while ensuring that ARMIN has at least the same capabilities as the Dali Architecture Reconstruction Workbench. During the reconstruction several architectural views were generated through abstraction of low-level information extracted from the system. These views show the components of the system and the interfaces among them. The ARMIN tool provides the ability to visualize, navigate, and manipulate the set of views generated, and yields results technically compatible with the Dali Workbench but with improved presentation and layout

This report outlines the application of architecture reconstruction techniques to the Sun Microsystems' Duke's Bank system- Java2 Platform, Enterprise Edition/Enterprise JavaBeans (J2EE/EJB) application implemented mainly in Java. The goal of the reconstruction was to apply architecture reconstruction techniques to a system implemented in Java to produce a set of views that depict that system's architecture. Decomposition style views of the module viewtype were used. They focus on the "is part of" relation and show how the system is decomposed into modules and submodules. During the reconstruction, several decomposition style views of the architecture were generated using the Understand for Java tool. That tool extracted and then abstracted low-level source information from the system. Then that information was formatted using Perl scripts, so it could be loaded into the Architecture Reconstruction and Mining (ARMIN) tool developed by the Carnegie Mellon Software Engineering Institute and the Robert Bosch Corporation. The resulting views showed the architectural elements of the Duke's Bank system and the dependencies among them.

This experience report outlines details of past and current architecture reconstruction work on several systems at Nokia. The Dali architecture reconstruction workbench developed by the Software Engineering Institute supported some of these efforts. Other efforts involved various tools and techniques, and in one case, the architecture reconstruction was performed manually. This report describes five such reconstruction efforts and outlines the observations noted and lessons learned while performing them. This report also offers some guidelines for those undertaking a reconstruction effort.

While it is commonly recognized that legacy assets are, in most cases, an important contributor to the core assets for software product lines, systematic methods for making decisions on when to incorporate legacy assets (versus building new assets) have not been available. Two methods developed by the Software Engineering Institute fill this gap: the Mining Architectures for Product Lines (MAP) method and the Options Analysis for Reengineering (OAR) method. Both of these methods, which are described in this report, support different aspects of the Product Parts Pattern, which is applied to develop the core assets for a product line. The MAP method provides a suitability analysis of existing systems' software architectures as candidates for a product line architecture. After an architecture has been developed or chosen, the OAR method provides a disciplined approach for making decisions on rehabilitating legacy assets that may be incorporated into the product line asset base. This technical note describes both the MAP and OAR methods, the activities that each involves, and examples of applying them.

The DoD often faces the challenge of migrating from legacy systems to new target systems. Such migration efforts represent a complex engineering problem. These efforts call for a migration plan to supplement the development plan. The migration plan addresses issues associated with phasing out legacy systems and moving to the new system. These issues include user interface compatibility, database compatibility, transition support, system interface compatibility, and training. By producing and implementing a migration plan, a development organization can help a user community make the transition in an orderly fashion. This note describes migration planning, identifies influencing factors, outlines a set of migration planning activities, and offers a set of guidelines for the migration planning process.

We present measurements of spin pumping detected by the inverse spin Hall effect voltage and ferromagnetic resonance spectroscopy in a series of metallic ferromagnet/normal metal thin film stacks. We compare heterostructures grown in situ to those where either a magnetic or nonmagnetic oxide is introduced between the two metals. The heterostructures, either nickel with a platinum overlayer (Ni/Pt) or the nickel-iron alloy permalloy (Py) with a gold overlayer (Py/Au), were also characterized in detail using grazing-incidence x-ray reflectivity, Auger electron spectroscopy, and both SQUID and alternating-gradient magnetometry. We verify the presence of oxide layers, characterize layer thickness, composition, and roughness, and probe saturation magnetization, coercivity, and anisotropy. The results show that while the presence of a nonmagnetic oxide at the interface suppresses spin transport from the ferromagnet to the nonmagnetic metal, a thin magnetic oxide (here the native oxide formed on both Py and Ni) somewhat enhances the product of the spin-mixing conductance and the spin Hall angle. We also observe clear evidence of an out-of-plane component of magnetic anisotropy in Ni/Pt samples that is enhanced in the presence of the native oxide, resulting in perpendicular exchange bias. Finally, the dc inverse spin Hall voltages generated at ferromagnetic resonance in our Py/Au samples are large, and suggest values for the spin Hall angle in gold of $0.04l{\ensuremath{\alpha}}_{\mathrm{SH}}l0.22$, in line with the highest values reported for Au. This is interpreted as resulting from Fe impurities. We present indirect evidence that the Au films described here indeed have significant impurity levels.