540,422 research outputs found
Key Capacity with Limited One-Way Communication for Product Sources
We show that for product sources, rate splitting is optimal for secret key
agreement using limited one-way communication at two terminals. This yields an
alternative proof of the tensorization property of a strong data processing
inequality originally studied by Erkip and Cover and amended recently by
Anantharam et al. We derive a `water-filling' solution of the
communication-rate--key-rate tradeoff for two arbitrarily correlated vector
Gaussian sources, for the case with an eavesdropper, and for stationary
Gaussian processes.Comment: 5 pages, ISIT 201
Bridging the Gap
School districts across the country are increasingly seeking out digital tools to support the work of educators, in the hopes of improving students' academic achievement. With the rapid emergence of this new market, many districts have been challenged by the task of identifying and procuring educational technology (ed-tech) products that match the needs of their educators and students.The NYC Department of Education's "Innovate NYC Schools" division, supported by a U.S. DOE Investing in Innovation (i3) grant, aims to address this problem, in part by promoting "user-centered design," an approach that puts the needs and preferences of products' intended users (in this case, teachers, students, and parents) front and center in the development and procurement of new technology.Bridging the Gap describes the design and implementation of three Innovate NYC Schools initiatives grounded in user-centered design theory:School Choice Design Challenge (SCDC),an effort to develop apps that would help students explore and narrow down their choices of high school.#SharkTankEDU events, during which ed-tech developers present a product to a panel of educators who provide feedback on the tool.Short-Cycle Evaluation Challenges (SCEC), a classroom-based, semester-long pilot of ed-tech tools intended to inform product development, as well as the ultimate procurement decisions of school staff.The report focuses on four phases of work involved in bringing ed-tech companies and the users of their products together: defining a problem; selecting users and ed-tech companies; implementing pilot-based initiatives; and evaluating products. It describes strategies used and challenges faced, and offers practical lessons gleaned from the experiences of the individuals who designed and participated in these efforts.
Separation of Reliability and Secrecy in Rate-Limited Secret-Key Generation
For a discrete or a continuous source model, we study the problem of
secret-key generation with one round of rate-limited public communication
between two legitimate users. Although we do not provide new bounds on the
wiretap secret-key (WSK) capacity for the discrete source model, we use an
alternative achievability scheme that may be useful for practical applications.
As a side result, we conveniently extend known bounds to the case of a
continuous source model. Specifically, we consider a sequential key-generation
strategy, that implements a rate-limited reconciliation step to handle
reliability, followed by a privacy amplification step performed with extractors
to handle secrecy. We prove that such a sequential strategy achieves the best
known bounds for the rate-limited WSK capacity (under the assumption of
degraded sources in the case of two-way communication). However, we show that,
unlike the case of rate-unlimited public communication, achieving the
reconciliation capacity in a sequential strategy does not necessarily lead to
achieving the best known bounds for the WSK capacity. Consequently, reliability
and secrecy can be treated successively but not independently, thereby
exhibiting a limitation of sequential strategies for rate-limited public
communication. Nevertheless, we provide scenarios for which reliability and
secrecy can be treated successively and independently, such as the two-way
rate-limited SK capacity, the one-way rate-limited WSK capacity for degraded
binary symmetric sources, and the one-way rate-limited WSK capacity for
Gaussian degraded sources.Comment: 18 pages, two-column, 9 figures, accepted to IEEE Transactions on
Information Theory; corrected typos; updated references; minor change in
titl
Synthesis of FMSP Experience and Lessons Learned for Fisheries Co-Management, Final Technical Report
In November 2012, the UK Department for International Development (DFID) set the terms of reference for a commissioned assessment of fisheries and aquaculture science. The task was to complete a "scoping review", consisting of an in-depth assessment of the existing evidence related to fisheries and aquaculture activities in developing countries and their contribution to economic growth, food security and nutrition. For this the assessment was expected to identify the existing evidence and 'evidence in the pipeline' (i.e. to be published imminently) from the existing literature, compile it, and provide an assessment of the strength (in the sense, scientific rigor) of that evidence, and identify knowledge or evidence gaps. In addition the assessment was to be complemented by a mapping of existing relevant interventions in fisheries and aquaculture. In order to conduct this assessment, the team of consultants adopted a six step methodological protocol that allowed them to assess in a consistent manner the scientific quality of the documents included in the assessment, based on quality, size and consistency of the evidence. After scanning, 202 documents were retained. The main evidences from these 202 documents were organised under two main threads: (i) Developmental outcomes, including food security; nutrition; health; economic growth and (ii) Mediating factors focusing on governance; and gender
Research for better aid: an evaluation of DFAT’s investments
Assesses the degree to which the investment by the Australian aid program into research has been appropriate, effective and efficient, and provides recommendations for improving DFAT’s future management of research investment.
Foreword
Explores how research investment can be best managed to ensure DFAT supports aid innovation and high-quality aid program and policy decision-making. The evaluation focuses on whether the management of DFAT’s considerable development research investment has been appropriate, effective and efficient. Employing a multi-dimensional evaluation method, it draws on the experiences of DFAT staff and stakeholders, as well as the available expenditure data, in arriving at a set of well-supported findings and recommendations.
The report makes several important points about the need for DFAT to have a clear sense about why and how it funds research. The department’s managers and officers need especially to be conscious of the effectiveness and efficiency risks implicit in their highly devolved form of research investment management. These risks will be reduced if robust knowledge management systems and a strong culture of research use are embedded in the department. The experience of other aid donors indicates that achieving this will be a significant challenge.
The evaluation also makes a finding with clear implications for the way the department engages with research institutions in partner countries. It shows that, while the department’s research funding to Australian institutions increased significantly from 2005 to 2013, the level of direct funding to partner country institutions did not increase to the same extent and was, indeed, flat over the last five years of that period. There are clear benefits to be had in building research capacity in those institutions, either directly or through partnerships with Australian and international researchers. Given Australia’s ongoing investment in the Pacific, this may be a region in which future research funding can be focused.
 
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References to past designs
Designing by adaptation is almost invariably a dominantambiguity feature of designing, and references to past designs are ubiquitous in design discourse. Object references serve as indices into designers' stocks of design concepts, in which memories for concrete embodiments and exemplars are tightly bound to solution principles. Thinking and talking by reference to past designs serves as a way to reduce the overwhelming complexity of complex design tasks by enabling designers to use parsimonious mental representations to which details can be added as needed. However object references can be ambiguous, and import more of the past design than is intended or may be desirable
Compressed Secret Key Agreement: Maximizing Multivariate Mutual Information Per Bit
The multiterminal secret key agreement problem by public discussion is
formulated with an additional source compression step where, prior to the
public discussion phase, users independently compress their private sources to
filter out strongly correlated components for generating a common secret key.
The objective is to maximize the achievable key rate as a function of the joint
entropy of the compressed sources. Since the maximum achievable key rate
captures the total amount of information mutual to the compressed sources, an
optimal compression scheme essentially maximizes the multivariate mutual
information per bit of randomness of the private sources, and can therefore be
viewed more generally as a dimension reduction technique. Single-letter lower
and upper bounds on the maximum achievable key rate are derived for the general
source model, and an explicit polynomial-time computable formula is obtained
for the pairwise independent network model. In particular, the converse results
and the upper bounds are obtained from those of the related secret key
agreement problem with rate-limited discussion. A precise duality is shown for
the two-user case with one-way discussion, and such duality is extended to
obtain the desired converse results in the multi-user case. In addition to
posing new challenges in information processing and dimension reduction, the
compressed secret key agreement problem helps shed new light on resolving the
difficult problem of secret key agreement with rate-limited discussion, by
offering a more structured achieving scheme and some simpler conjectures to
prove
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