Search

AbstractMachine Learning (ML) is increasingly becoming a crucial asset across diverse industries. However, designers lack human-centered processes to envision and develop innovative solutions enabled by ML. By engaging in a Research-through-Design activity, we outline a new design process to generate human-centered adaptive systems enabled by data and ML. We describe and discuss the possibilities and limits of designing with ML, the need to concurrently address user experience and ML aspects, and the implications of their mutual influence. We argue that designers can envision and design human-centered ML-enabled systems if they acquire fundamental ML knowledge, although certain tasks necessitate close collaboration with ML experts. We discuss how uncertainty and risk of failure characterize the outlined process and may limit its applicability. The proposed process serves as a foundational framework for future research in human-centered design innovation through data and ML.

n‐Butyric, iso‐butyric, n‐valeric and iso‐valeric esters of hydroxypropylcellulose were synthesized. Their behaviors, in terms of cholesteric structure, glass (Tg) and anisotropic‐isotropic (Ti) transition temperatures are compared to results in the literature. A 6–8 month time period from sample preparation has no influence on the cholesteric phase characteristics. Six binary blends may be formed from the four esters. They show only a Tgvalue at each composition, which suggests a good miscibility among the components. However, positive deviation of linearity of Tgvs. composition varies from one pair to another. Analysis of the absorption curves in UV‐vis spectra show that three pairs form a single cholesteric helix containing both components while other three give a only nematic phase. Colors changing from red to violet are shown for blends of n‐butyric and iso‐butyric esters at different weight ratio. Copyright © 2003 John Wiley & Sons, Ltd.

n-Butyric, iso-butyric, n-valeric and iso-valeric esters of hydroxypropylcellulose were synthesized. Their behaviors, in terms of cholesteric structure, glass (Tg) and anisotropic-isotropic (Ti) transition temperatures are compared to results in the literature. A 6–8 month time period from sample preparation has no influence on the cholesteric phase characteristics. Six binary blends may be formed from the four esters. They show only a Tg value at each composition, which suggests a good miscibility among the components. However, positive deviation of linearity of Tg vs. composition varies from one pair to another. Analysis of the absorption curves in UV-vis spectra show that three pairs form a single cholesteric helix containing both components while other three give a only nematic phase. Colors changing from red to violet are shown for blends of n-butyric and iso-butyric esters at different weight ratio. Copyright © 2003 John Wiley & Sons, Ltd.

A simple method is reported allowing the fast evaluation of the athermal limit that is implicitly present within the set of equations recently proposed by Jonah, Brostow and Hess, dealing with the anisotropic-isotropic equilibria of single monodisperse or nearly monodisperse semirigid liquid polymers, including polymer liquid crystals. We have found an athermal limit dependent on the degree of rigidity θ of the given semirigid liquid polymer (θ being the fraction of its monomeric units belonging to rigid rodlike sequences within each semiflexible polymeric chain) and marked off by critical lengths ηal of the rigid sequences, giving rise to non-finite asymptotic values of the anisotropic-isotropic temperatures.

A simple method is reported allowing the fast evaluation of the athermal limit that is implicitly present within the set of equations recently proposed by Jonah, Brostow and Hess, dealing with the anisotropic‐isotropic equilibria of single monodisperse or nearly monodisperse semirigid liquid polymers, including polymer liquid crystals. We have found an athermal limit dependent on the degree of rigidity θof the given semirigid liquid polymer (θbeing the fraction of its monomeric units belonging to rigid rodlike sequences within each semiflexible polymeric chain) and marked off by critical lengths ηalof the rigid sequences, giving rise to non‐finite asymptotic values of the anisotropic‐isotropic temperatures.

It has been found that a method allowing the calculation of an anisotropic‐isotropic transition volume fraction for a given semirigid polymer can be derived from the equations recently proposed by Blonski and coworkers to evaluate the equilibrium compositions of isotropic and anisotropic phases coexisting within ternary systems semirigid polymer/flexible polymer/solvent. By using the term anisotropic‐isotropic transition volume fraction of a semirigid polymer we will refer to its smallest volume fraction giving an anisotropic character to liquid ternary phases also including a flexible polymer and a solvent. Its evaluation simplifies the construction of the corresponding ternary diagram and can also be seen as a fast and quantitative way of estimating the influence exerted by the semirigid polymer, through its intrinsic anisotropy, on ternary phases.

Following early work by Kutzelnigg on the correlation cusp, we have attempted to improve convergence of the damped multipole expansion of the second-order induction energy for H++ by including a separately determined cusp correction of the form φ = f(rB)ψ0 into the first-order function in order to avoid divergency at the proton position when rB = 0. Three different cusp wavefunctions, all derived from the Taylor expansion of f(rB) into positive powers of rB have been examined, and the best compromise between simplicity and accuracy is found for the function φ = -rBψ0. Few residual multipoles, variationally approximated in terms of one-centre linear pseudostates, are then found necessary to reproduce accurately the induction energy at the distance of the chemical bond.

The improvement in the convergence rate of the damped multipole expansion for the second order H-H+ induction energy due to the inclusion into the first-order function of a term satisfying the electron-proton cusp condition is quantitatively investigated. Following a technique suggested by Schwartz, the multipole contributions to the energy are put in the form of series ordered by inverse powers of the quantum number l. It is shown that, for high values of l, the dependence of the leading terms is raised from l-4 to l-6 by the cusp correction.

A fast and simple method has been found to solve the set of equations recently proposed by Jonah, Brostow and Hess [Macromolecules26, 76 (1993)], allowing the evaluation of the anisotropic‐isotropic transition temperature for a semirigid liquid polymer. Starting with given values of η (average length of the rigid sequences coexisting with flexible sequences inside the semiflexible polymer chains) and θ (degree of rigidity of the semirigid polymer), a reduced transition temperature τ is readily obtained, together with the transition values of the anisotropic order parameters sand γ.

The perturbative configuration interaction approach based on non-orthogonal bond-orbitals previously used for dealing with rotational barriers is applied to the study of the hydrogen bonding in the linear water dimer. First and second-order interaction energies are obtained in terms of static and transition charge distributions fully accounting for intermolecular overlap. Neglecting electron correlation, the second-order calculations include all single excitations from bonding to antibonding orbitals accounting for induction including exchange and giving results close to the corresponding supermolecular SCF-MOs in the same basis. Ab initio calculations using different gaussian minimal bases show that Clementi's GTO basis MEDIUM is the most suitable for describing molecular interactions. Detailed component analysis of the energy up to second order is possible and reveals the main features of the intermolecular hydrogen bonding occurring between the water molecules.

The N-term representation of the H atom static propagator in terms of a finite discrete set of linear excited pseudostates involving positive powers of the radial variable is used to calculate multipole components of nonexpanded induction and dispersion interactions at the bond length for H+2 and H2, nonexpanded dispersion coefficients for H2, and hydrogenic second-order energy for the He sequence. Even if convergence is sensibly slower than that observed for expanded perturbations, the N = 20 approximation is found to give results at worst within 1% of the accurate reference values from the literature.