Selecting and assessing challenge problems

Abstract

Organisations conducting research programs often focus the work of their scientists and technologists on challenge problems (CPs). These challenges are designed to ensure that progress is measurable and relevant to the goals of the program sponsor. Generating and selecting pertinent CPs is difficult, as is assessing their value. We describe a method of generating and selecting CPs and its application in a highly collaborative, multi-organisation research program. Thirty-eight biologists, chemists, mathematicians and computer scientists across academic, commercial and government organisations generated and ranked their top choices from among 12 richly described candidate challenge problems. A ranked-choice voting formula was applied. Five CPs were highly scored; the remaining seven were distributed across a lower range of scores. The program sponsor subsequently directed researchers to address six CPs, including the elected five. Analysis of the rationales that participants offered for their CP rankings revealed four domain-independent dimensions of value: capability, speed, impact and synergy. These dimensions of value can help managers of interdisciplinary research programs systematically select a portfolio of CPs that will efficiently apply utilise resources towards program goals and facilitate measurement of scientific progress.     

CYPHER MACHINES MAINTENANCE AND RESTORATION SPANNING SIXTY YEARS

We describe the life and times of a servicing mechanic for cypher equipment for the Royal Air Force during World War II and an opportunity to serve again as a cypher machine restorer for Bletchley Park Museum.     

Avalanches on a conical bead pile: scaling with tuning parameters

Uniform spherical beads were used to explore the scaling behavior of a granular system near its critical angle of repose on a conical 3D bead pile. We found two tuning parameters that could take the system to a critical point. The existence of those tuning parameters violates the fundamental assumption of self-organized criticality, which proposed that complex dynamical systems self-organize to a critical point without need for tuning. Our avalanche size distributions were well described by a simple power-law, as is characteristic of a critical point, with the power τ = 1.5 when dropping beads slowly onto the apex of a bead pile from a small height. However, we could also move the system from the critical point using either of two tuning parameters: the height from which the beads fell onto the top of the pile or the region over which the beads struck the pile. As the drop height increased, the system did not reach the critical point yet the resulting distributions were independent of the bead mass, coefficient of friction, or coefficient of restitution. All our apex-dropping distributions for any type of bead (glass, stainless steel, zirconium) showed universality by scaling onto a common curve with τ = 1.5 and σ =?1.0, where 1/σ is the power of the tuning parameter. From independent calculations using the moments of the distribution, we find values for τ = 1.6 ± 0.1 and σ =?0.91 ± 0.15. When beads were dropped across the surface of the pile instead of solely on the apex, then the system also moved from the critical point and again the avalanche size distributions fell on a common curve when scaled similarly using the same values of τ and σ. We also observed that an hcp structure on the base of the pile caused an emergent structure in the pile that had six faces with some fcc or hcp structure; this structure did not affect the distribution of avalanche sizes.     

Consumer Input for Developing Human Food Products Made with Sorghum Grain

Abstract: Because sorghum grain has important characteristics (for example, great antioxidant profile) for introduction into the regular human diet, producers and industry aim to develop successful products using sorghum as the base. The 1st step in developing products attractive for consumers is understanding consumer needs and expectations. Conjoint analysis determines attributes which may be important or unimportant for one product. In this study, focus groups and conjoint analysis were used to establish which attributes are helpful for promoting purchase intent of sorghum grain products. Once those characteristics were chosen, a national survey was conducted to confirm the selection. During the focus groups, the heath aspects of grain products seemed to be the most appealing for consumers, whereas conjoint analysis showed that sensory attributes were the principal drivers for purchase intent. Practical Application: The data presented in this study are essential for industry as a starting point for developing sorghum grain based food products. It is necessary to address consumers’ demands to ensure new products’ success in the market, and the present study clearly shows this consumers’ input.     

Using disability data to estimate design exclusion

Exclusion auditing is a process that can quantitatively evaluate the inclusive merit of different products, or alternative design decisions. The results from such an audit can provide prioritised directions for product improvement and support the business case for reducing the capability levels required to use mainstream products. The 1996/1997 disability follow-up survey, conducted by the Office of National Statistics, is currently the most comprehensive data source for estimating design exclusion in the UK. In this paper, the data source is explained in detail, and a method is presented that uses this data to estimate the exclusion associated with several tasks that occur in series or in parallel, illustrated through worked examples. Having evaluated how many people are excluded, one can investigate why they were excluded, thus generating design insights into how they could be included. Data from the survey is also converted to a series of stylised graphs, which are intended to inspire designers to think about the relationship between the demands required to use a product and the resulting levels of population exclusion.     

Genotoxic potential of aqueous extracts of Artemisia verlotorum on the cell cycle of Allium cepa

Artemisia verlotorum, popularly ‘infalivina’, is a medicinal herb used for respiratory, circulatory and digestive treatments. Antiproliferative and genotoxic effects of A. verlotorum aqueous extracts in three different concentrations (6, 32 and 48 g/L) were evaluated on the Allium cepa cell cycle. Results clearly showed a significant difference using the χ² test (p = 0.05) among treatments with a decrease in the mitotic index as the concentration of the extract increased. Extracts of A. verlotorum proved to be genotoxic and showed antiproliferative potential on the A. cepa cell cycle. This study suggests the use of infusions of A. verloturum for medicinal purposes only after selecting suitable concentrations.