371,909 research outputs found
A Universal Quantum Circuit Scheme For Finding Complex Eigenvalues
We present a general quantum circuit design for finding eigenvalues of
non-unitary matrices on quantum computers using the iterative phase estimation
algorithm. In particular, we show how the method can be used for the simulation
of resonance states for quantum systems
Slime mould tactile sensor
Slime mould P. polycephalum is a single cells visible by unaided eye. The
cells shows a wide spectrum of intelligent behaviour. By interpreting the
behaviour in terms of computation one can make a slime mould based computing
device. The Physarum computers are capable to solve a range of tasks of
computational geometry, optimisation and logic. Physarum computers designed so
far lack of localised inputs. Commonly used inputs --- illumination and
chemo-attractants and -repellents --- usually act on extended domains of the
slime mould's body. Aiming to design massive-parallel tactile inputs for slime
mould computers we analyse a temporal dynamic of P. polycephalum's electrical
response to tactile stimulation. In experimental laboratory studies we discover
how the Physarum responds to application and removal of a local mechanical
pressure with electrical potential impulses and changes in its electrical
potential oscillation patterns
HCI for peace: from idealism to concrete steps
This panel will contribute diverse perspectives on the use of computer technology to promote peace and prevent armed conflict. These perspectives include: the use of social media to promote democracy and citizen participation, the role of computers in helping people communicate across division lines in zones of conflict, how persuasive technology can promote peace, and how interaction design can play a role in post-conflict reconciliation
Design and Implementation of a Distributed Middleware for Parallel Execution of Legacy Enterprise Applications
A typical enterprise uses a local area network of computers to perform its
business. During the off-working hours, the computational capacities of these
networked computers are underused or unused. In order to utilize this
computational capacity an application has to be recoded to exploit concurrency
inherent in a computation which is clearly not possible for legacy applications
without any source code. This thesis presents the design an implementation of a
distributed middleware which can automatically execute a legacy application on
multiple networked computers by parallelizing it. This middleware runs multiple
copies of the binary executable code in parallel on different hosts in the
network. It wraps up the binary executable code of the legacy application in
order to capture the kernel level data access system calls and perform them
distributively over multiple computers in a safe and conflict free manner. The
middleware also incorporates a dynamic scheduling technique to execute the
target application in minimum time by scavenging the available CPU cycles of
the hosts in the network. This dynamic scheduling also supports the CPU
availability of the hosts to change over time and properly reschedule the
replicas performing the computation to minimize the execution time. A prototype
implementation of this middleware has been developed as a proof of concept of
the design. This implementation has been evaluated with a few typical case
studies and the test results confirm that the middleware works as expected
Learning and interaction in groups with computers: when do ability and gender matter?
In the research reported in this paper, we attempt to identify the background and process factors influencing the effectiveness of groupwork with computers in terms of mathematics learning. The research used a multi-site case study design in six schools and involved eight groups of six mixed-sex, mixed-ability pupils (aged 9-12) undertaking three research tasks – two using Logo and one a database. Our findings suggest that, contrary to other recent research, the pupil characteristics of gender and ability have no direct influence on progress in group tasks with computers. However, status effects – pupils' perceptions of gender and ability – do have an effect on the functioning of the group, which in turn can impede progress for all pupils concerned
A novel representation of energy and signal transformation in measurement systems
This work presents a novel representation of energy and signal transformation in a measurement system, which is essentially a transducer conversion logic or language (TCL). Using two-port and three-port transducers as basic building blocks, it can be utilized to model any measurement system. It has the key features of object-orientation and consists of only text with very simple syntax. The TCL can be easily handled and processed by computers. This paper has demonstrated its use in description, classification, and computer-aided analysis and design of measuring instruments with some preliminary test results. It will find wide applications in modeling, analysis, design, and education in measurement, control, and information processing
Express: a web-based technology to support human and computational experimentation
Experimental cognitive psychology has been greatly assisted by the development of general computer-based experiment presentation packages. Typically, however, such packages provide little support for running participants on different computers. It is left to the experimenter to ensure that group sizes are balanced between conditions and to merge data gathered on different computers once the experiment is complete. Equivalent issues arise in the evaluation of parameterized computational models, where it is frequently necessary to test a model's behavior over a range of parameter values (which amount to between-subjects factors) and where such testing can be speeded up significantly by the use of multiple processors. This article describes Express, a Web-based technology for coordinating "clients" (human participants or computational models) and collating client data. The technology provides an experiment design editor, client coordination facilities (e.g., automated randomized assignment of clients to groups so that group sizes are balanced), general data collation and tabulation facilities, a range of basic statistical functions (which are constrained by the specified experimental design), and facilities to export data to standard statistical packages (such as SPSS). We report case studies demonstrating the utility of Express in both human and computational experiments. Express may be freely downloaded from the Express Web site (http://express.psyc.bbk.ac.uk/)
Towards trusted volunteer grid environments
Intensive experiences show and confirm that grid environments can be
considered as the most promising way to solve several kinds of problems
relating either to cooperative work especially where involved collaborators are
dispersed geographically or to some very greedy applications which require
enough power of computing or/and storage. Such environments can be classified
into two categories; first, dedicated grids where the federated computers are
solely devoted to a specific work through its end. Second, Volunteer grids
where federated computers are not completely devoted to a specific work but
instead they can be randomly and intermittently used, at the same time, for any
other purpose or they can be connected or disconnected at will by their owners
without any prior notification. Each category of grids includes surely several
advantages and disadvantages; nevertheless, we think that volunteer grids are
very promising and more convenient especially to build a general multipurpose
distributed scalable environment. Unfortunately, the big challenge of such
environments is, however, security and trust. Indeed, owing to the fact that
every federated computer in such an environment can randomly be used at the
same time by several users or can be disconnected suddenly, several security
problems will automatically arise. In this paper, we propose a novel solution
based on identity federation, agent technology and the dynamic enforcement of
access control policies that lead to the design and implementation of trusted
volunteer grid environments.Comment: 9 Pages, IJCNC Journal 201
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