Quantum Cryptography in Practice

BBN, Harvard, and Boston University are building the DARPA Quantum Network, the world's first network that delivers end-to-end network security via high-speed Quantum Key Distribution, and testing that Network against sophisticated eavesdropping attacks. The first network link has been up and steadily operational in our laboratory since December 2002. It provides a Virtual Private Network between private enclaves, with user traffic protected by a weak-coherent implementation of quantum cryptography. This prototype is suitable for deployment in metro-size areas via standard telecom (dark) fiber. In this paper, we introduce quantum cryptography, discuss its relation to modern secure networks, and describe its unusual physical layer, its specialized quantum cryptographic protocol suite (quite interesting in its own right), and our extensions to IPsec to integrate it with quantum cryptography.Comment: Preprint of SIGCOMM 2003 pape

Sabotage! And Other Stories

This is a collection of short stories written from 2008-2010

A problem structuring method for ecosystem-based management : the DPSIR modelling process

The purpose of this paper is to learn from Complex Adaptive Systems (CAS) theory to inform the development of Problem Structuring Methods (PSMs) both in general and in the specific context of marine management. The focus on marine management is important because it is concerned with a CAS (formed through the interconnection between natural systems, designed systems and social systems) which exemplifies their particularly ‘wicked' nature. Recognition of this compels us to take seriously the need to develop tools for knowledge elicitation and structuring which meet the demands of CAS. In marine management, chief among those tools is the DPSIR (Drivers - Pressures - State Changes - Impacts - Responses) model and, although widely applied, the extent to which it is appropriate for dealing with the demands of a CAS is questionable. Such questioning is particularly pertinent in the context of the marine environment where there is a need to not only recognise a broad range of stakeholders (a question of boundary critique) but also to manage competing knowledge (economic, local and scientific) and value claims. Hence this paper emphasises how a CAS perspective might add impetus to the development of a critical perspective on DPSIR and PSM theory and practice to promote a more systemic view of decision-making and policy development

Management of the marine environment: Integrating ecosystem services and societal benefits with the DPSIR framework in a systems approach

Ever increasing and diverse use of the marine environment is leading to human-induced changes in marine life, habitats and landscapes, making necessary the development of marine policy that considers all members of the user community and addresses current, multiple, interacting uses. Taking a systems approach incorporating an understanding of The Ecosystem Approach, we integrate the DPSIR framework with ecosystem services and societal benefits, and the focus this gives allows us to create a specific framework for supporting decision making in the marine environment. Based on a linking of these three concepts, we present a set of basic postulates for the management of the marine environment and emphasise that these postulates should hold for marine management to be achieved. We illustrate these concepts using two case studies: the management of marine aggregates extraction in UK waters and the management of marine biodiversity at Flamborough Head, UK. (C) 2010 Elsevier Ltd. All rights reserved

A classification of finite rank dimension groups by their representations in ordered real vector spaces

Peer reviewedPostprin

In Situ Thermal Inspection of Automated Fiber Placement Operations for Tow and Ply Defect Detection

The advent of Automated Fiber Placement (AFP) systems have aided the rapid manufacturing of composite aerospace structures. One of the challenges that AFP systems pose is the uniformity of the deposited prepreg tape layers, which complicates detection of laps, gaps, overlaps and twists. The current detection method used in industry involves halting fabrication and performing a time consuming, visual inspection of each tape layer. Typical AFP systems use a quartz lamp to heat the base layer to make the surface tacky as it deposits another tape layer. The innovation proposed in this paper is to use the preheated base layer as a through-transmission heat source for inspecting the newly added tape layer in situ using a thermographic camera mounted on to the AFP hardware. Such a system would not only increase manufacturing throughput by reducing inspection times, but it would also aid in process development for new structural designs or material systems by providing data on as-built parts. To this end, a small thermal camera was mounted onto an AFP robotic research platform at NASA, and thermal data was collected during typical and experimental layup operations. The data was post processed to reveal defects such as tow overlap/gap, wrinkling, and peel-up. Defects that would have been impossible to detect visually were also discovered in the data, such as poor/loss of adhesion between plies and the effects of vacuum debulking. This paper will cover the results of our experiments, and the plans for future versions of this inspection system

The Effects of Short-Term Storage on Germination in Meconopsis Vig. (Papaveraceae)

The viability and germination rate of seed of five species and four cultivars of Meconopsis was tested. The seed was stored in both refrigerated (c.4°C) conditions and at ambient temperature (8–17°C) to reflect typical conditions for seed storage in the smaller botanical garden and amateur enthusiast’s collection. Seed that had been stored in each of these conditions was sown sequentially 2, 3, 4 and 5 months after harvest. Seed batches were also treated with 0.25mg/l gibberellic acid (GA) or left untreated. Each of the four combination treatments was associated with an overall reduction in viability and germination rate as time after harvest increased (to a minimum of 66.7% viability and 33.7% germination, except for two species with high viability but no germination in the study period). These reductions were not significantly different between treatments, and use of GA did not significantly increase germination rate. We studied the role of underlying genetic relations on germination by relating our results to the most recent comprehensive phylogeny of the genus, and we suggest that ecology plays a more important role than phylogeny in germination

Best Practices in Suicide Pedagogy: A Quantitative Content Analysis

The authors used a quantitative content analysis methodology to explore the available literature on pedagogical practices for teaching counselors how to work with suicidal clients. From an initial pool of 71 potentially applicable articles found in Counseling, Psychiatry, general mental health, Psychology, and Social Work journals, 26 articles were found to meet inclusion criteria by specifically exploring the impact or efficacy of different pedagogical practices relevant to suicide response in counselor training. These 26 articles were coded using quantitative content analysis procedures. Results indicated that more research is necessary to determine best practices for teaching suicide response to counselors in training. Additionally, these training practices should include attention to the CACREP standards and should be theoretically grounded in pedagogical frameworks. Ideally, future research in this area would focus more heavily on assessment of student competencies and how well students are prepared to respond to suicide

Deconstructing therapy outcome measurement with Rasch analysis of a measure of general clinical distress: the Symptom Checklist-90-Revised

Rasch analysis was used to illustrate the usefulness of item-level analyses for evaluating a common therapy outcome measure of general clinical distress, the Symptom Checklist-90-Revised (SCL-90-R; Derogatis, 1994). Using complementary therapy research samples, the instrument's 5-point rating scale was found to exceed clients' ability to make reliable discriminations and could be improved by collapsing it into a 3-point version (combining scale points 1 with 2 and 3 with 4). This revision, in addition to removing 3 misfitting items, increased person separation from 4.90 to 5.07 and item separation from 7.76 to 8.52 (resulting in alphas of .96 and .99, respectively). Some SCL-90-R subscales had low internal consistency reliabilities; SCL-90-R items can be used to define one factor of general clinical distress that is generally stable across both samples, with two small residual factors