High-speed pulse-train generation using single-mode-fibre recirculating delay lines

A simple technique is described, whereby the delay properties of a series of two single-mode-fibre recirculating delay lines were used to generate a sequence of uniform, high-speed pulse trains. A single, short input was used to generate a sequence of 1.25 Gbit/s pulse trains that were uniform to better than ±0.3 dB.     

Robust reverse production system design for carpet recycling

It is estimated that complete carpet recycling would avoid an estimated US annual landfill cost of $65 million, while simultaneously recovering lost material valued at $750 million. Designing an adequate reverse production system is critical to the economic viability of recovering this lost value. We develop a robust-mixed-integer linear programming model to support decision-making for reverse production infrastructure design. Our robust model seeks solutions close to the mathematically optimal solutions for a set of alternative scenarios identified by a decision-maker. To demonstrate the approach, a representative industrial case study is given for a large-scale carpet recycling problem. A robust solution is found that appraises the impact of two major sources of uncertainty, volumes of carpet collected and price of a key recycled material.     

Connecting to the vision [next generation intelligence]

Next generation intelligence of the 21st century will contain three central tenets that govern the performance of organizations: vision, connection, and build. Next generation intelligence such as multi-agent system software means that by factoring in attributes such as cost, assets, quality, time-to-market, customer satisfaction, finance, logistics, manufacturing, demand scheduling, scenario planning, and strategic and operational contingencies, it can convert concepts into specifications, and specifications into profits. Radio frequency identification (RFID) technologies also offer organizations greater supply chain visibility and control over their security and assets such as inventory and working capital, in stock and in transit. In this article, an application of next generation intelligence in the automotive industry is presented.     

Transactional Confidentiality in Sensor Networks

In a sensor network environment, elements such as message rate, message size, mote frequency, and message routing can reveal transactional data—that is, information about the sensors deployed, frequency of events monitored, network topology, parties deploying the network, and location of subjects and objects moving through the networked space. Whereas the confidentiality of network communications content is secured through encryption and authentication techniques, the ability of network outsiders and insiders to observe transactional data can also compromise network confidentiality. Four types of transactional data are typically observable in sensor networks. Measures to limit the availability and utility of transactional data are essential to preserving confidentiality in sensor networks.     

Direct synthesis of formate from methanol oxidation on the CuPd[85∶15]{110}p(2×1) surface: induction of a new reaction pathway via a ligand effect

Thermal molecular beam studies of the oxidative dehydrogenation of methanol over the 1/4 ML and 1/2 ML oxygen predosed CuPd[85 15]{110}p(2 × 1) surfaces has been performed. Post reaction thermal desorption spectroscopy (TDS) clearly shows that during these experiments observable levels of formate are produced. This is in contrast to the results of similar experiments performed over oxidised Cu{110} surfaces which showed little formate production. It is hypothesised that the alloying in the surface region causes this new reaction pathway to appear as a consequence of a modification of the stability of one or more of the reactive intermediates produced in this reaction. It is proposed that these modifications of adsorbate stability are due to a ligand effect arising from the presence of Pd in the second layer of the selvedge.     

A new method for the generation of aerosols of insoluble particles

A method for the controlled generation of spherical aerosol particles of insoluble metal oxides has been developed. The method consists of (a) nebulizing a solution (or suspension) of the chosen metal in chelated or other form, (b) drying the droplets, (c) passing the aerosol through a high temperature heating column to produce the spherical oxide particles, and (d) cooling the aerosol with the addition of diluting air. This procedure provides a continuous source of insoluble aerosols suitable for animal inhalation exposures or other experimental uses. The size distribution of an aerosol produced by this method depends upon the distribution of the nebulized droplets. This technique has been used with a Fulwyler Droplet Generator to produce monodisperse aerosols.

The physical and chemical nature of aerosols of zirconium and lanthanum compounds generated by this method were studied. Physical characteristics were ascertained by electron-microscopic observations, particle density measurements, and aerodynamic sampling; and chemical properties by tracer and instrumental techniques.