A simple digital circuit for the Towers of Hanoi problem

A digital circuit is presented for the Towers of Hanoi problem based upon its iterative algorithm. This provides a case study to illustrate synchronous design principles and the correspondence between hardware and software functions     

Interventions for long-term software security: Creating a lightweight program of assurance techniques for developers

Though some software development teams are highly effective at delivering security, others either do not care or do not have access to security experts to teach them how. Unfortunately, these latter teams are still responsible for the security of the systems they build: systems that are ever more important to ever more people. We propose that a series of lightweight interventions, six hours of facilitated workshops delivered over three months, can improve a team's motivation to consider security and awareness of assurance techniques, changing its security culture even when no security experts are involved. The interventions were developed after an Appreciative Inquiry and Grounded Theory survey of security professionals to find out what approaches work best. We tested the interventions in a participatory action research field study where we delivered the workshops to three software development organizations and evaluated their effectiveness through interviews beforehand, immediately afterwards, and after twelve months. We found that the interventions can be effective with teams with limited or no security experience and that improvement is long-lasting. This approach and the learning points arising from the work here have the potential to be applied in many development teams, improving the security of software worldwide.     

A 16-Mbit/s adapter chip for the IBM token-ring local area network

The authors describe a 9.02×9.02-mm chip built in 1-μm CMOS with two levels of metal and an additional mask level for fabricating capacitors. It contains both analog and digital circuits and has provisions for self-test. The function includes the transmitter, receiver, protocol handler, an microprocessor, as well as interfaces for RAM/ROM storage, IBM PC bus, IBM PS/2 bus, IBM 3174 bus, and Motorola 68000 bus. The physical design terrains are formed by 24K circuits of standard cell gates, a 10K-circuit equivalent hand-honed custom microprocessor, and an analog macro. The chip operates from a single 5-V supply, and the power consumption is 0.8 W nominal at 16 Mb/s. The chip can also be operated at 4 Mb/s     

The effect of coalescence on drop size distribution in an agitated liquid-liquid dispersion

A procedure involving high speed cine photography and novel optical probes has been used to study droplet interaction phenomena in liquid-liquid dispersions. Coalescence and breakup events were observed and the rate of coalescence was measured at various positions in a stirred tank for dispersions of methylisobutylketone in water. For the conditions studied, drop breakup occurred near the impeller and droplet coalescence predominated at other locations, as expected. However, the extent of this behavior was unexpected. Beyond distances from the impeller region of order of only $\text{1}\text{6}$ the impeller diameter, breakup was virtually nonexistent. Outside the impeller region, extensive coalescence measurements showed (1) collisions between droplets are extremely inefficient for this chemically equilibrated system—at most 10% of collisions result in a coalescence, (2) only binary coalescence occurs even at the highest dispersed phase concentration investigated, (3) coalescence rate shows little preference on drop size, and (4) the coalescence rate is directly proportional to turbulence level; that is, the highest coalescence rates occur closest to the impeller. On the basis of these measurements, drop balance methods and a circulation path model were used to relate the drop size distribution at various locations in the region where coalescence predominates. In this case good agreement was obtained between measured and predicted drop size distributions.     

Improved myoelectric prosthesis control using targeted reinnervation surgery: a case series.

Targeted reinnervation is a surgical technique developed to increase the number of myoelectric input sites available to control an upper-limb prosthesis. Because signals from the nerves related to specific movements are used to control those missing degrees-of-freedom, the control of a prosthesis using this procedure is more physiologically appropriate compared to conventional control. This procedure has successfully been performed on three people with a shoulder disarticulation level amputation and three people with a transhumeral level amputation. Performance on timed tests, including the box-and-blocks test and clothespin test, has increased two to six times. Options for new control strategies are discussed.     

Two-dimensional micropipelines: for parallel-to-serial dataconversion

The two-dimensional micropipeline is introduced for data conversion between bit-parallel and bit-serial formats at a constant input data rate. By using micropipelines, the architecture has independent clock rates for the data input and output, and can be designed with level sensitive latches     

Standards and platforms for open distributed processing

There has recently been considerable research and development in the field of open distributed processing. The goal of this work is to enable access to distributed services without concern for the underlying environment. A number of standards and platforms have emerged to achieve this goal. This paper provides a tutorial introduction to these initiatives. In particular, the paper examines the ISO standard for a reference model for open distributed processing, OMG's CORBA and OSF's DCE. The paper concludes that these initiatives are different in scope and should be viewed as complementary. The paper also speculates on a path to convergence between the three initiatives although a number of issues remain to be solved before such a convergence can become a reality     

Associative activation of stimulus representations restores lost salience: Implications for perceptual learning.

In 3 experiments, rats received preexposure to presentations of a compound flavor BX. The effective salience of B was then tested by assessing its ability to interfere with the aversion controlled by another flavor or the tendency to drink a saline solution after the induction of a salt need. It was found that the effective salience of B was maintained when during preexposure, presentations of BX alternated with presentations of X alone. This was true both when BX was presented as a simultaneous compound (Experiment 1) and as a serial compound (X→B; Experiments 2 and 3); salience was not maintained when the serial compound took the form B→X (Experiments 2 and 3a). It was argued that the salience of B declines during preexposure but is restored when presentations of X are able to activate the representation of B by way of the associative X-B link. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Personal time management for busy managers

Personal time management is a systematic application of commonsense strategies. It requires little effort, yet it promotes efficient work practices by highlighting wastage and it leads to effective use of time by focusing it on the chosen activities. The author looks at the basics of personal time management and describes how the manager can assume control of this basic resource