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AmbieSense: a system and reference architecture for personalised and context-sensitive information services for mobile users
The purpose of AmbieSense is to provide personalised, context-sensitive information to the mobile user. It is about augmenting digital information to physical objects, rooms, and areas. The aim is to provide relevant information to the right user and situation. Digital content is distributed from the surroundings and onto your mobile phone. An ambient information environment is provided by a combination of context tag technology, a software platform to manage and deliver the information, and personal computing devices to which the information is served. This paper describes how the AmbieSense reference architecture has been defined and used in order to deliver information to the mobile citizen at the right time, place and situation. Information is provided via specialist content providers. The application area addresses the information needs of travellers and tourists
Reinventing Media Activism: Public Interest Advocacy in the Making of U.S. Communication-Information Policy, 1960-2002
This report is a long-term analysis of citizens' collective action to influence public policy toward communication and information. The work discusses in greater detail what is meant by communication and information policy (CIP) and why we think it is worthwhile to study it as a distinctive domain of public policy and citizen action. The report concentrates on citizen action in the United States and looks backwards, tracing the long-term evolutionary trajectory of communications-information advocacy in the USA since the 1960s. We focus on the concept of citizen collective action and explain its relevance to CIP.Research supported by the Ford Foundation's Knowledge, Creativity and Freedom Program. The views expressed are those of the author and do not necessarily represent the views of the School of Information Studies, Syracuse University, or the Ford Foundation
Network Expansion Decision-making in the Twin Cities
This paper presents a qualitative analysis of the decision-rules used by jurisdictions in Minnesota's Twin Cities metropolitan area. Interviews were conducted with staff at the city, county, metropolitan, and state levels to determine how decisions about road investment, expansion and new construction were made. Flowcharts were developed to provide a more systematic way of presenting that information. Most jurisdictions do not have extensive public participation processes, though several, notably the Metropolitan Council, Hennepin and Ramsey Counties and the City of Minneapolis do. Jurisdictions with public participation have the most formal and extensive documentation of their investment decision process. The decision factors vary by jurisdiction, though safety, capacity, and pavement quality were important throughout.
Distinguishing Internet-facing ICS devices using PLC programming information
The Shodan search engine reveals Industrial Control System (ICS) devices around the globe are directly connected to the Internet. After Shodan\u27s inception in 2009, multiple news reports have focused on the increased threat to infrastructure posed by Shodan. While no attacks to date have been directly attributed to Shodan searches, its existence provides an anonymous reconnaissance platform that facilitates ICS targeting for those actors with both a desire and capability to carry out attacks. Recent research has demonstrated that simple search queries return thousands of ICS devices indexed by Shodan, and the number of newly indexed ICS devices is growing. This research discusses the method used to distinguish the Internet-facing ICS devices indexed by the Shodan search engine. PLC code is obtained by sending specifically crafted CIP request messages to the devices, capitalizing on the fact that authentication is not built in to the CIP application layer protocol. This data allows categorization of Internet-facing devices by comparing PLC code attributes. The results of this research show PLC code can be collected from Internet-facing ICS devices with no significant impact to task execution times. Also, this research demonstrates a method to distinguish Internet-facing ICS devices by function and by Critical Infrastructure sector. This capability develops an understanding of the function and purpose of ICS devices that are being connected to the Internet
MiniCPS: A toolkit for security research on CPS Networks
In recent years, tremendous effort has been spent to modernizing
communication infrastructure in Cyber-Physical Systems (CPS) such as Industrial
Control Systems (ICS) and related Supervisory Control and Data Acquisition
(SCADA) systems. While a great amount of research has been conducted on network
security of office and home networks, recently the security of CPS and related
systems has gained a lot of attention. Unfortunately, real-world CPS are often
not open to security researchers, and as a result very few reference systems
and topologies are available. In this work, we present MiniCPS, a CPS
simulation toolbox intended to alleviate this problem. The goal of MiniCPS is
to create an extensible, reproducible research environment targeted to
communications and physical-layer interactions in CPS. MiniCPS builds on
Mininet to provide lightweight real-time network emulation, and extends Mininet
with tools to simulate typical CPS components such as programmable logic
controllers, which use industrial protocols (Ethernet/IP, Modbus/TCP). In
addition, MiniCPS defines a simple API to enable physical-layer interaction
simulation. In this work, we demonstrate applications of MiniCPS in two example
scenarios, and show how MiniCPS can be used to develop attacks and defenses
that are directly applicable to real systems.Comment: 8 pages, 6 figures, 1 code listin
Power consumption modeling in optical multilayer networks
The evaluation of and reduction in energy consumption of backbone telecommunication networks has been a popular subject of academic research for the last decade. A critical parameter in these studies is the power consumption of the individual network devices. It appears that across different studies, a wide range of power values for similar equipment is used. This is a result of the scattered and limited availability of power values for optical multilayer network equipment. We propose reference power consumption values for Internet protocol/multiprotocol label switching, Ethernet, optical transport networking and wavelength division multiplexing equipment. In addition we present a simplified analytical power consumption model that can be used for large networks where simulation is computationally expensive or unfeasible. For illustration and evaluation purpose, we apply both calculation approaches to a case study, which includes an optical bypass scenario. Our results show that the analytical model approximates the simulation result to over 90% or higher and that optical bypass potentially can save up to 50% of power over a non-bypass scenario
A Cycle-Based Formulation and Valid Inequalities for DC Power Transmission Problems with Switching
It is well-known that optimizing network topology by switching on and off
transmission lines improves the efficiency of power delivery in electrical
networks. In fact, the USA Energy Policy Act of 2005 (Section 1223) states that
the U.S. should "encourage, as appropriate, the deployment of advanced
transmission technologies" including "optimized transmission line
configurations". As such, many authors have studied the problem of determining
an optimal set of transmission lines to switch off to minimize the cost of
meeting a given power demand under the direct current (DC) model of power flow.
This problem is known in the literature as the Direct-Current Optimal
Transmission Switching Problem (DC-OTS). Most research on DC-OTS has focused on
heuristic algorithms for generating quality solutions or on the application of
DC-OTS to crucial operational and strategic problems such as contingency
correction, real-time dispatch, and transmission expansion. The mathematical
theory of the DC-OTS problem is less well-developed. In this work, we formally
establish that DC-OTS is NP-Hard, even if the power network is a
series-parallel graph with at most one load/demand pair. Inspired by Kirchoff's
Voltage Law, we give a cycle-based formulation for DC-OTS, and we use the new
formulation to build a cycle-induced relaxation. We characterize the convex
hull of the cycle-induced relaxation, and the characterization provides strong
valid inequalities that can be used in a cutting-plane approach to solve the
DC-OTS. We give details of a practical implementation, and we show promising
computational results on standard benchmark instances
USTOPIA REQUIREMENTS THOUGHTS ON A USER-FRIENDLY SYSTEM FOR TRANSFORMATION OF PROGRAMS IN ABSTRACTO
Transformational programming is a program development method which is usually applied
using 'pen and paper'. Since this requires a lot of clerical work (copying expressions, con-
sistent substitution) which is tiresome and prone to error, some form of machine support is
desirable. In this paper a number of systems are described that have already been built to
this aim. Some of their shortcomings and limitations are identified. Based on experience
with program transformation and transformation systems, a long list of features is given
that would be useful in an 'utopian' transformation system. This list is presented using
an orthogonal division of the problem area. A number of problems with the realisation of
some aspects of our 'utopian' system are identified, and some areas for further research
are indicated
The Impact of Agricultural Technology in Sub-Saharan Africa: A Synthesis of Symposium Findings
The Symposium on the Impact of Technology on Agricultural Transformation in Sub-Saharan Africa funded by AID/AFR/ARTS and AID/RD/EID under the Michigan State University Food Security Cooperative Agreements, was held in Washington, D.C., Oct. 14-16, 1992. A primary purpose of the symposium was to present evidence which would either confirm or contradict the perception that the accomplishments of TDT were insufficient to justify continued funding. A secondary objective was to consider the adequacy of available analytical tools for impact assessment. The rate of return (ROR) is the most commonly used valuative measure of investments in technology development and transfer. Examined as a group, the estimated RORs support the proposition that African agricultural research has had people-level impacts, and that these impacts are large enough to justify the level of investment that led to the impacts. An important part of the impact assessment story is the analysis of factors that had a positive or negative effect on the impact of TDT. Five major factors emerged from the studies presented and comments by symposium participants: agroclimatic conditions, civil unrest, research system performance, policy, and markets. Progress has been made in moving forward with the process of TDT, in spite of adverse conditions. This progress includes enhancing the capabilities of national, regional and international institutions to generate new techniques, pushing forward the technology frontier, transferring technology, and increasing productivity both in farm production and post-harvest activities. Activities such as structural adjustment, improvements in agricultural and macroeconomic policy, greater reliance on democracy and capitalism, investments in infrastructure, and a greater willingness to work with the private sector have increased the potential for TDT to have significant impact. Given the importance of raising productivity in agriculture as a step towards agricultural transformation, continued investment in agricultural TDT is merited. The evidence of impact achieved from previous investments shows that those investments have paid off. Coupled with the evidence of beneficial changes in the macroeconomic policy environment in many countries, this provides the basis for expecting that future investments will pay off. What is perhaps unique about the symposium is the movement towards a commodity sector perspective as the next logical step toward including more demand-side considerations in the TDT agenda.International Development, Research and Development/Tech Change/Emerging Technologies, Downloads July 2008 - June 2009: 18,
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