The Creative Neurons

Creativity generates novel solutions to tasks by processing information. Imagination and mental representations are part of the creative process; we can mull over ideas of our own making, and construct algorithms or scenarios from them. Social scenario-building can be viewed as a human cognitive “super-power” that involves abstraction, meta-representation, time-travel, and directed imaginative thought. We humans have a “theater in our minds” to play out a near-infinite array of social strategies and contingencies. Here we propose an integrative model for why and how humans evolved extraordinary creative abilities. We posit that a key aspect of hominin evolution involved relatively open and fluid social relationships among communities, enabled by a unique extended family structure similar to that of contemporary hunter-gatherer band societies. Intercommunity relationships facilitated the rapid flow of information—“Culture”—that underpinned arms-races in information processing, language, imagination, and creativity that distinguishes humans from other species.

Absorption of Light in Finite Semiconductor Nanowire Arrays and the Effect of Missing Nanowires

When modelling the absorption in semiconductor nanowire (NW) arrays for solar cell and photodetector applications, the array is typically assumed to be infinitely periodic such that a single unit cell suffices for the simulations. However, any actual array is of a finite extent and might also show varying types of localized defects such as missing or electrically non-contacted individual NWs. Here, we study InP NWs of 2000 nm in length and 180 nm in diameter, placed in a square array of 400 nm in period, giving a rather optimized absorption of sunlight. We show that the absorption in the center NW of a finite N × N array converges already at N = 5 close to the value found for the corresponding infinite array. Furthermore, we show that a missing NW causes an enhanced absorption in neighboring nanowires, which compensates for 77% of the absorption loss due to the missing NW. In other words, an electrically non-contacted NW, which absorbs light but cannot contribute to the external short-circuit current, is a four times worse defect than a missing NW.

Assessment of Low-Re Turbulence Models and Analysis of Turbulent Flow in Porous Media Consisting of Square Cylinders With Different Diameter Ratios

This paper presents a comparative study of volume average predictions between low-Reynolds-number (LRN) turbulence models: Abe–Kondoh–Nagano (AKN), Lam–Bremhorst, Yang–Shih, standard k–ϵ, and k–ω. A porous medium, which represents conditions in which the flow path changes rapidly, was defined as an infinite array of square cylinders. In addition, to explore the effect of particle size on the rapid expansion and contraction of the flow paths, the diameter ratio (DR) of the square cylinders was systematically varied from 0.2 to 0.8. This generalization revealed new insights into the flow. The Reynolds number (ReD) covered a turbulent range of 500 to 500 × 103, and the porosity ϕ was varied from 0.27 to 0.8. The correlations of the turbulent kinetic energy (k), its dissipation rate (ε), and macroscopic pressure gradient as a function of ϕ, which are useful in macroscopic turbulence modeling, are presented. The results show that the AKN model yields better predictions of the volume-averaged flow parameters because it is better suited to reproduce recirculation zones. For all the DRs, at high ϕ, the distances between walls are high, and the interstitial velocities are low. Consequently, wake flows are produced, and energy losses by friction are moderate. As the flow becomes increasingly bound, the wakes are suppressed and disrupted, and k and ε increase owing to shear layer interactions and frictional forces. Distinctive low-velocity recirculation patterns appear inside pores depending on DR.

Ultrawideband, Wide Scanning Stripline-Fed Tightly Coupled Array Antenna Based on Parallel-Dipole Elements

A stripline-fed tightly coupled array antenna with compact size, large scan volume and low cross-polarization characteristics is proposed for ultrawideband (UWB) applications. Simple impedance-matching process is realized by using parallel dual dipoles. Meanwhile, the parallel symmetrical radiating structures minimize the cross-polarization field components dramatically. The mitigation of various undesired resonances is studied in detail. An infinite array is designed to achieve 3:1 bandwidth (6−18 GHz) when scanning ±60∘ in the E-/D-planes (VSWR < 2.5) and H-plane (VSWR < 3.5). The cross-polarization levels remain below −29 dB at broadside. A 16 × 16 prototype is fabricated to demonstrate the design. The measured results are consistent well with the simulated ones. The overall size of the prototype at the lowest operating frequency is 3×3×0.4λ03 (15×15×2cm3). Due to its wide bandwidth, good electronic scan performance and compact size, the proposed antenna array is a good candidate for modern wireless platforms.

Practical design of Ku band Vivaldi antenna array

In the paper, a practical design of a Ku-band Vivaldi antenna array for compact radar system is presented. The realized gain, the beam width, polarization purity and the possible electronic beamforming in the horizontal plane were the most important requirements. Since the array was requested to show an enhanced mechanical stability, a novel geometry of elements was proposed. The Vivaldi slot was created on two substrates connected by metallic vias suppressing surface currents, and the microstrip feeder was placed in-between those substrates. Simulations are based on special approach in CST Microwave using infinite array of antenna elements, which should reduce computing time.

Historical Research: The Origin of ‘Formula’: State of the Science, 1890s

In 1900, 13% of infants in the United States died before their first birthday, most of dehydration from diarrhea. As part of a nationwide effort to “save the babies,” pediatricians focused on several endeavors—experimenting with commercially made infant-food products; working with dairy farmers to clean up cows’ milk; lobbying to pass municipal and state legislation regulating the dairy industry; and devising mathematical “formulas” that represented instructions to chemists on how to “humanize” cows’ milk for the needs of a particular infant. Pediatricians dubbed the latter endeavor “percentage feeding” and, from the 1890s to the 1920s, they deemed percentage feeding a lifesaving scientific achievement. The complex, virtually infinite array of mathematical formulas that comprised this infant-feeding system is the origin of the word “formula” as used today to describe artificial baby milk.

The Part Is Greater Than the Whole

Pure cinema is defined in terms of the interrelationship of formal “fragments” that subtend an infinite array of formal systems within the work. In this model, the aesthetic philosophy of the fragment is developed through the seminal work of Raymond Bellour, one of the most astute of the classical Hitchcockian theorists. The fragment structures aesthetic form across mise en scène, montage, sound design, and narrative. The philosophy of the fragment is read in further detail and greater philosophical specificity through the historical tension between Eisenstein’s montage as whole and Deleuze’s attempts to read montage through the itinerary of the part. The resonance or vibration of the part is read as intensity, structuring the “excessive affect” that underpins the aesthetic of the fragment in film form. The aesthetic of the fragment is revealed in close formal analyses in Hitchcock’s North by Northwest, Argento’s Suspiria, and De Palma’s Union Station sequence in The Untouchables.

Revisiting the Casimir energy with general boundary conditions and applications in 1D crystals

We obtain new expressions for the Casimir energy between plates that are mimicked by the most general possible boundary conditions allowed by the principles of quantum field theory. This result enables to provide the quantum vacuum energy for scalar fields propagating under the influence of a one-dimensional crystal represented by a periodic potential formed by an infinite array of identical potentials with compact support.

Back scattering response from single, finite and infinite array of nonlinear antennas based on intelligent water drops algorithm

Purpose The purpose of this paper is to calculate the back scattering response from single, finite and infinite arrays of nonlinear antennas like the case where the antennas are exposed to high-value signals such as lightning strokes. Design/methodology/approach In this paper, the authors have used a recently introduced optimization technique called intelligent water drop. Findings The results exhibit that the method used by the authors is faster and more accurate than other conventional optimization algorithms, i.e. particle swarm optimization and genetic algorithm. Originality/value A new optimization algorithm is used to solve nonlinear problem accurately and sufficiently. Although the technique is not confined to the mentioned examples in the paper, it can be applied to other nonlinear circuits.