‘A Pretence of What is Not’? A Study of Simulation(s) from the ENIAC Perspective

What is the significance of high-speed computation for the sciences? How far does it result in a practice of simulation which affects the sciences on a very basic level? To offer more historical context to these recurring questions, this paper revisits the roots of computer simulation in the development of the ENIAC computer and the Monte Carlo method.

With the aim of identifying more clearly what really changed (or not) in the history of science in the 1940s and 1950s due to the computer, I will emphasize the continuities with older practices and develop a two-fold argument. Firstly, one can find a diversity of practices around ENIAC which tends to be ignored if one focuses only on the ENIAC itself as the originator of Monte Carlo simulation. Following from this, I claim, secondly, that there was no simulation around ENIAC. Not only is the term ‘simulation’ not used within that context, but the analysis also shows how ‘simulation’ is an effect of three interrelated sets of different practices around the machine: (1) the mathematics which the ENIAC users employed and developed, (2) the programs, (3) the physicality of the machine. I conclude that, in the context discussed, the most important shifts in practice are about rethinking existing computational methods. This was done in view of adapting them to the high-speed and programmability of the new machine. Simulation then is but one facet of this process of adaptation, singled out by posterity to be viewed as its principal aspect.

     

A note on ‘A bit-wise mutation algorithm for mixed-model sequencing in JIT production systems’ (Nazar & Pillai, 2015, IJPR, 53:19, 5931-5947)

This note discusses three points about the problem of sequencing units on a mixed-model assembly line in ‘A bit-wise mutation algorithm for mixed-model sequencing in JIT production systems’ (Nazar & Pillai, 2015, IJPR, 53:19, 5931-5947). Specifically, the mixed-integer quadratic model, the bit-wise mutation algorithm and the bi-objective problem to optimise both product rate variation and makespan. The conclusion of the discussion is that the three alleged contributions are not valid or are outperformed by those presented in some previously published papers.     

The development of ‘green’ airports: Which factors influence willingness to pay for sustainability and intention to act? A structural and mediation model analysis

The study's purpose was to determine which factors influence a consumer's willingness to pay for sustainability and their intention to take action against climate change related to airports. An expanding body of literature relates to assessing whether consumers would be willing to pay for these ‘green’ practices in the aviation industry, such as biofuels or sustainable airport construction/renovations. While previous studies have experimentally examined these scenarios, we are aware of no prior research that has proposed and assessed a structural model related to determining which factors influence consumer's perspectives on ‘green’ airports. A sample of 722 eligible participants from the United States completed the study using Amazon's Mechanical Turk. We examined future time perspective, affect toward climate change, the perceived value of sustainability, and perceptions of climate change on the endogenous variables of willingness to pay for sustainability and intentions to take action against climate change. Six of the seven hypotheses proposed were supported. Affect, perceived value, and perceptions of climate change were all significant and positively related to willingness to pay, which was positively associated with intention to act. Two non-hypothesized paths, between perceived value and future time perspective, were also positively related to intention to act. The model explained 42% of the variance in willingness to pay and 66% in intention to act. These findings offer insights into what factors significantly influence these relationships as they relate to airports. Perceived value and perceptions of climate change had the largest effect sizes in the model and were significantly related to willingness to pay and intentions to act.     

New Perspectives for Cuprate Research: (Ca x La1?x )(Ba1.75?x La0.25+x )Cu3O y Single Crystals

We report the successful growth of a large (Ca _x La_1?x )(Ba_1.75?x La_0.25+x )Cu₃O _y (CLBLCO) single crystal. In this material, x controls the maximum of T _c ( $T_{c}^{\max }$ ), with minimal structural changes. Therefore, it allows a search for correlations between material properties and $T_{c}^{\max }$ . We demonstrate that the crystals are good enough for neutron scattering and cleave well enough for Raman scattering. These results open new possibilities for cuprate research.     

Surface contact and design of fibrillar ‘friction pads’ in stick insects (Carausius morosus): mechanisms for large friction coefficients and negligible adhesion

Many stick insects and mantophasmids possess tarsal ‘heel pads’ (euplantulae) covered by arrays of conical, micrometre-sized hairs (acanthae). These pads are used mainly under compression; they respond to load with increasing shear resistance, and show negligible adhesion. Reflected-light microscopy in stick insects (Carausius morosus) revealed that the contact area of ‘heel pads’ changes with normal load on three hierarchical levels. First, loading brought larger areas of the convex pads into contact. Second, loading increased the density of acanthae in contact. Third, higher loads changed the shape of individual hair contacts gradually from circular (tip contact) to elongated (side contact). The resulting increase in real contact area can explain the load dependence of friction, indicating a constant shear stress between acanthae and substrate. As the euplantula contact area is negligible for small loads (similar to hard materials), but increases sharply with load (resembling soft materials), these pads show high friction coefficients despite little adhesion. This property appears essential for the pads’ use in locomotion. Several morphological characteristics of hairy friction pads are in apparent contrast to hairy pads used for adhesion, highlighting key adaptations for both pad types. Our results are relevant for the design of fibrillar structures with high friction coefficients but small adhesion.     

Public Policies to Support Basic Research: What Can the Rest of the World Learn from US Theory and Practice? (And What They Should Not Learn)

The information-based theoretical model for public support ofbasic research, developed in the USA at the end of the 1950s,has held up well in political practice, in spite of its neglectof training benefits, of necessary prior investment in researchinfrastructure and of its consequently limited relevance outsidethe USA. At the same time, US practice in basic research hasoften been misinterpreted as being driven by short-term usefulness,whereas its key features are massive and pluralistic governmentfunding, high academic quality, and the ability to invest inthe long-term development of new (often multidisciplinary) fields.Challenges for the future include greater (and often ill-judged)pressures from governments for demonstrable usefulness of thebasic research it supports, the entirely separate developmentof direct links to application in biomedical and software fields,and more complicated links between national basic research andapplication resulting from the changes in the internationalizationof corporate R&D. And perhaps we can learn as much fromsuccessful practices in Scandinavia and Switzerland as fromthe USA.     

Ion-exchange studies of ‘organic–inorganic’ nano-composite cation-exchanger: Poly-o-anisidine Sn(IV) tungstate and its analytical application for the separations of toxic metals

The separation of Hg(II) from aqueous solutions was studied using Poly-o-anisidine Sn(IV) tungstate nano-composite cation exchanger. This nano-composite material was synthesized via sol–gel mixing of Poly-o-anisidine with the inorganic precipitate of Sn(IV) tungstate, providing a new class of organic–inorganic nano-composite cation exchanger with good ion-exchange capacity, better chemical and thermal stability than most of the Poly-o-anisidine based exchanger reported so far. The ion-exchange capacity and ion-exchange behaviors of the nano-composite were also carried out to understand the ion-exchange capabilities. Its selectivity was examined by achieving some important binary and tertiary separations of metal cations on its column indicating its utility in environmental pollution control. This new exchanger was successfully applied for quantitative determination and separation of Hg(II) from a synthetic mixture of metal ions.     

The accidental risk assessment methodology for industries (ARAMIS)/layer of protection analysis (LOPA) methodology: A step forward towards convergent practices in risk assessment?

In the last ten years, layer of protection analysis (LOPA) emerged as a simplified form of quantitative risk assessment (QRA). The European Commission funded project Accidental Risk Assessment Methodology for Industries in the context of the Seveso 2 Directive (ARAMIS) has recently been completed. ARAMIS has several modules which give a consistent simplified approach to risk assessment which does not approach the complexity or expense of full QRA. LOPA is potentially a means of carrying out the assessment of barriers required in ARAMIS. This paper attempts to explain the principles of LOPA and the means by which it can be used within ARAMIS.     

The rise and fall of the Belgian Forestry Museum and Geographic Arboretum (1900–1980): A political origin and a winning opportunity for science?

This paper recounts the genesis and further developments of two devices that were created in Brussels and nearby around 1900: the Forestry Museum and the Geographic Arboretum in Tervuren. Both the Museum and the Arboretum were designed to serve botanical science, national industry, and agriculture, but also became instrumental in carrying philosophical and political messages and even in achieving down‐to‐earth political aims. The Museum, imposed upon the State Botanic Garden by a Catholic ministry, carried out messages for social pacification, while also taking to the battlefield in the fight between what were then called pure science and applied science. For its part, the Geographic Arboretum had long broken its ties with the State Botanic Garden and even with its own scientific claims by the time the Forestry Museum disappeared in the early 1980s. However, the Forestry Museum had increasingly lost its vocation as a research tool, eventually and solely becoming a tool of communication toward an ever‐widening public, following Belgian society's expanding democratization in the late 19th Century. The lives and fortunes of both devices reveal most of the tensions that rhythmed the history of museums and the political history of a European country.