49,584 research outputs found

    Coupling Products and Services in Design Processes: A Case Study of Smart Drip

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    Design evolution is sequential and progressively associated with industrial and technological developments as well as human lifestyle needs. In response to current design trends toward smart products, this study presents a new perspective on product-service design to facilitate the design of innovative products. The proposed approach focuses on applying TRIZ to developing a physical product associated with its possible service supports to fulfill customers’ demands. It is based on the construct that every aspect of product and service quality should be taken into account as a whole in the early design stage. A case study of intravenous infusion(smart drip) design was conducted to demonstrate the applicability of the proposed approach.     Keywords: product-service design, TRIZ, smart product, intravenous infusion, case stud

    Magnetic susceptibility of alkali-TCNQ salts and extended Hubbard models with bond order and charge density wave phases

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    The molar spin susceptibilities χ(T)\chi(T) of Na-TCNQ, K-TCNQ and Rb-TCNQ(II) are fit quantitatively to 450 K in terms of half-filled bands of three one-dimensional Hubbard models with extended interactions using exact results for finite systems. All three models have bond order wave (BOW) and charge density wave (CDW) phases with boundary V=Vc(U)V = V_c(U) for nearest-neighbor interaction VV and on-site repulsion UU. At high TT, all three salts have regular stacks of TCNQ\rm TCNQ^- anion radicals. The χ(T)\chi(T) fits place Na and K in the CDW phase and Rb(II) in the BOW phase with VVcV \approx V_c. The Na and K salts have dimerized stacks at T<TdT < T_d while Rb(II) has regular stacks at 100K. The χ(T)\chi(T) analysis extends to dimerized stacks and to dimerization fluctuations in Rb(II). The three models yield consistent values of UU, VV and transfer integrals tt for closely related TCNQ\rm TCNQ^- stacks. Model parameters based on χ(T)\chi(T) are smaller than those from optical data that in turn are considerably reduced by electronic polarization from quantum chemical calculation of UU, VV and tt on adjacent TCNQ\rm TCNQ^- ions. The χ(T)\chi(T) analysis shows that fully relaxed states have reduced model parameters compared to optical or vibration spectra of dimerized or regular TCNQ\rm TCNQ^- stacks.Comment: 9 pages and 5 figure

    Quantum Shock Waves - the case for non-linear effects in dynamics of electronic liquids

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    Using the Calogero model as an example, we show that the transport in interacting non-dissipative electronic systems is essentially non-linear. Non-linear effects are due to the curvature of the electronic spectrum near the Fermi energy. As is typical for non-linear systems, propagating wave packets are unstable. At finite time shock wave singularities develop, the wave packet collapses, and oscillatory features arise. They evolve into regularly structured localized pulses carrying a fractionally quantized charge - {\it soliton trains}. We briefly discuss perspectives of observation of Quantum Shock Waves in edge states of Fractional Quantum Hall Effect and a direct measurement of the fractional charge

    Persistence length of a polyelectrolyte in salty water: a Monte-Carlo study

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    We address the long standing problem of the dependence of the electrostatic persistence length lel_e of a flexible polyelectrolyte (PE) on the screening length rsr_s of the solution within the linear Debye-Huckel theory. The standard Odijk, Skolnick and Fixman (OSF) theory suggests lers2l_e \propto r_s^2, while some variational theories and computer simulations suggest lersl_e \propto r_s. In this paper, we use Monte-Carlo simulations to study the conformation of a simple polyelectrolyte. Using four times longer PEs than in previous simulations and refined methods for the treatment of the simulation data, we show that the results are consistent with the OSF dependence lers2l_e \propto r_s^2. The linear charge density of the PE which enters in the coefficient of this dependence is properly renormalized to take into account local fluctuations.Comment: 7 pages, 6 figures. Various corrections in text and reference

    Pre- and Post-Adaptation Effects of Buffers in High-Concentrate Lamb Diets

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    A gradual increase in grain cover a period of 2 to 4 weeks is commonly required before ruminant animals become adapted to high-concentrate diets. Various dietary materials including sodium bicarbonate, sodium betonite, limestone and forage have been indicated as potential adis in the prevention of acidosis during adaptation. Benefits from feeding of these materials following adaptation have been less pronounced or lacking. Objectives of studies reported herein were (1) to investigate the effects of buffers and limited quantitites of alfalfa hay on physiological and rumen fermentation changs occuring in lambs during the early phase of adaptation to high-concentrate diets and (2) to study ruminal and systemic parameters and nutrient utilization as influenced by buffers in the diets of lambs previously adapted to the high-concentrate diet

    Deep Neural Networks Rival the Representation of Primate IT Cortex for Core Visual Object Recognition

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    The primate visual system achieves remarkable visual object recognition performance even in brief presentations and under changes to object exemplar, geometric transformations, and background variation (a.k.a. core visual object recognition). This remarkable performance is mediated by the representation formed in inferior temporal (IT) cortex. In parallel, recent advances in machine learning have led to ever higher performing models of object recognition using artificial deep neural networks (DNNs). It remains unclear, however, whether the representational performance of DNNs rivals that of the brain. To accurately produce such a comparison, a major difficulty has been a unifying metric that accounts for experimental limitations such as the amount of noise, the number of neural recording sites, and the number trials, and computational limitations such as the complexity of the decoding classifier and the number of classifier training examples. In this work we perform a direct comparison that corrects for these experimental limitations and computational considerations. As part of our methodology, we propose an extension of "kernel analysis" that measures the generalization accuracy as a function of representational complexity. Our evaluations show that, unlike previous bio-inspired models, the latest DNNs rival the representational performance of IT cortex on this visual object recognition task. Furthermore, we show that models that perform well on measures of representational performance also perform well on measures of representational similarity to IT and on measures of predicting individual IT multi-unit responses. Whether these DNNs rely on computational mechanisms similar to the primate visual system is yet to be determined, but, unlike all previous bio-inspired models, that possibility cannot be ruled out merely on representational performance grounds.Comment: 35 pages, 12 figures, extends and expands upon arXiv:1301.353

    Bethe Ansatz solution of a new class of Hubbard-type models

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    We define one-dimensional particles with generalized exchange statistics. The exact solution of a Hubbard-type Hamiltonian constructed with such particles is achieved using the Coordinate Bethe Ansatz. The chosen deformation of the statistics is equivalent to the presence of a magnetic field produced by the particles themselves, which is present also in a ``free gas'' of these particles.Comment: 4 pages, revtex. Essentially modified versio

    Singular Cucker-Smale Dynamics

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    The existing state of the art for singular models of flocking is overviewed, starting from microscopic model of Cucker and Smale with singular communication weight, through its mesoscopic mean-filed limit, up to the corresponding macroscopic regime. For the microscopic Cucker-Smale (CS) model, the collision-avoidance phenomenon is discussed, also in the presence of bonding forces and the decentralized control. For the kinetic mean-field model, the existence of global-in-time measure-valued solutions, with a special emphasis on a weak atomic uniqueness of solutions is sketched. Ultimately, for the macroscopic singular model, the summary of the existence results for the Euler-type alignment system is provided, including existence of strong solutions on one-dimensional torus, and the extension of this result to higher dimensions upon restriction on the smallness of initial data. Additionally, the pressureless Navier-Stokes-type system corresponding to particular choice of alignment kernel is presented, and compared - analytically and numerically - to the porous medium equation

    Single-cell RNA sequencing identifies distinct mouse medial ganglionic eminence cell types.

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    Many subtypes of cortical interneurons (CINs) are found in adult mouse cortices, but the mechanism generating their diversity remains elusive. We performed single-cell RNA sequencing on the mouse embryonic medial ganglionic eminence (MGE), the major birthplace for CINs, and on MGE-like cells differentiated from embryonic stem cells. Two distinct cell types were identified as proliferating neural progenitors and immature neurons, both of which comprised sub-populations. Although lineage development of MGE progenitors was reconstructed and immature neurons were characterized as GABAergic, cells that might correspond to precursors of different CINs were not identified. A few non-neuronal cell types were detected, including microglia. In vitro MGE-like cells resembled bona fide MGE cells but expressed lower levels of Foxg1 and Epha4. Together, our data provide detailed understanding of the embryonic MGE developmental program and suggest how CINs are specified

    Analysis of dynamical corrections to baryon magnetic moments

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    We present and analyze QCD corrections to the baryon magnetic moments in terms of the one-, two-, and three-body operators which appear in the effective field theory developed in our recent papers. The main corrections are extended Thomas-type corrections associated with the confining interactions in the baryon. We investigate the contributions of low-lying angular excitations to the moments quantitatively and show that they are completely negligible. When the QCD corrections are combined with the non-quark model contributions of the meson loops, we obtain a model which describes the moments within a mean deviation of 0.04 μN\mu_N. The nontrivial interplay of the two types of corrections to the quark-model moments is analyzed in detail, and explains why the quark model is so successful. In the course of these calculations, we parametrize the general spin structure of the j=1/2+j={1/2}^+ baryon wave functions in a form which clearly displays the symmetry properties and the internal angular momentum content of the wave functions, and allows us to use spin-trace methods to calculate the many spin matrix elements which appear in the expressions for the moments. This representation may be useful elsewhere.Comment: 32 pages, 3 figures, submitted to Phys. Rev.
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