Silver coated textile for versatile personal thermal management via multi-order reflections

Personal thermal management (PTM) is of paramount importance for reducing energy consumption and improving the thermal comfort of individuals. However, wearable textile via facile methods for indoor/outdoor PTM is still challenging. Here we present a novel simple yet effective method for versatile PTM via silver coated textile. Infrared transmittance of coated fabric is greatly enhanced by 150% due to the multi-order reflection of silver coating. Based on their IR radiative cooling, in indoor and outdoor, the skin surface temperature is lower by 1.1˚C and 0.9˚C than normal cloth, allowing the textile to be used in multiple environments. Moreover, the coated fabric is capable of active warming up under low voltage, which can be used in low-temperature conditions. These promising results exemplify the practicability of using silver coated textile as a personal thermal management cloth in versatile environments.

Revolution or Rejection?

Mark S. Massa’s The Structure of Theological Revolutions: How the Fight Over Birth Control Transformed American Catholicism is a study on two levels. On one level, it is a study of the responses of select American moral theologians to Pope Paul VI’s 1968 encyclical on contraception, Humanae vitae (hereafter, HV). On another level, it is a second-order reflection on these theological responses, using them as data, as it were, for a theory about how theology changes or does not change over time. The book certainly succeeds on the first level. I am not sure, however, that that success translates easily to the second level. To the extent that it is possible, I would like to work with these levels successively, even if, for Massa, the two are accomplished simultaneously, since the narration of the “brilliance” (passim) of the individuals treated is tied to the narration of how each of them radically broke with the paradigm of natural law that Massa claims is enshrined in HV.

Characterization of Second-Order Reflection Bands from a Cholesteric Liquid Crystal Cell Based on a Wavelength-Swept Laser

We report the results of an experimental study of the characterization of second-order reflection bands from a cholesteric liquid crystal (CLC) cell that depends on the applied electric field, using a wide bandwidth wavelength-swept laser. The second-order reflection bands around 1300 nm and 1500 nm were observed using an optical spectrum analyzer when an electric field was applied to a horizontally oriented electrode cell with a pitch of 1.77 μm. A second-order reflection spectrum began to appear when the intensity of the electric field was 1.03 Vrms/μm with the angle of incidence to the CLC cell fixed at 36°. The reflectance increased as the intensity of the electric field increased at an angle of incidence of 20°, whereas at an incident angle of 36°, when an electric field of a predetermined value or more was applied to the CLC cell, it was confirmed that deformation was completely formed in the liquid crystal and the reflectance was saturated to a constant level. As the intensity of the electric field increased further, the reflection band shifted to a longer wavelength and discontinuous wavelength shift due to the pitch jump was observed rather than a continuous wavelength increase. In addition, the reflection band changed when the angle of incidence on the CLC cell was changed. As the angle of incidence gradually increased, the center wavelength of the reflection band moved towards shorter wavelengths. In the future, we intend to develop a device for optical wavelength filters based on side-polished optical fibers. This is expected to have a potential application as a wavelength notch filter or a bandpass filter.

SURFACE WAVE SCATTERING BY AN ELASTIC PLATE SUBMERGED IN WATER WITH UNEVEN BOTTOM

Wave interaction with a vertical elastic plate in presence of undulating bottom topography is considered, assuming linear theory and utilizing simple perturbation analysis. First order correction to the velocity potential corresponding to the problem of scattering by a vertical elastic plate submerged in a fluid with a uniform bottom is obtained by invoking the Green’s integral theorem in a suitable manner. With sinusoidal undulation at the bottom, the first-order transmission coefficient (T1) vanishes identically. Behaviour of the first order reflection coefficient (R1) depending on the plate length, ripple number, ripple amplitude and flexural rigidity of the plate is depicted graphically. Also, the resonant nature of the first order reflection is observed at a particular value of the ratio of surface wavelength to that of the bottom undulations. The net reflection coefficient due to the joint effect of the plate and the bottom undulation is also presented for different flexural rigidity of the plate. When the rigidity parameter is made sufficiently large, the results for R1 reduce to the known results for a surface piercing rigid plate in water with bottom undulation.

Conceptualism and Perceptual Knowledge

Brief accounts of the motivation and form of some pre-Kantian conceptualist theories and of Kant’s transcendental idealism lead into discussion of the source of the conceptualist assumptions of much twentieth-century analytic philosophy. The arguments of a currently leading exponent, John McDowell, are critically examined, and his emphatic endorsement of two main conclusions of Chapter II are noted—that perception is direct cognitive contact with the world, and that perceptual knowledge is perspicuously so to the subject. But according to the phenomenological analysis in Chapter II these features are intrinsic to the content of preconceptual perceptual awareness, whereas McDowell sees concepts, coming only with language, as a necessary means to the former, and assigns the latter, in effect, to reason and the capacity for second-order reflection. Epistemological and logico–linguistic considerations relating to the identity, individuation and classification of material things present a further, arguably decisive challenge to conceptualist theory.

A STUDY OF TRUTH PREDICATES IN MATRIX SEMANTICS

Abstract algebraic logic is a theory that provides general tools for the algebraic study of arbitrary propositional logics. According to this theory, every logic ${\cal L}$ is associated with a matrix semantics $Mo{d^{\rm{*}}}{\cal L}$. This article is a contribution to the systematic study of the so-called truth sets of the matrices in $Mo{d^{\rm{*}}}{\cal L}$. In particular, we show that the fact that the truth sets of $Mo{d^{\rm{*}}}{\cal L}$ can be defined by means of equations with universally quantified parameters is captured by an order-theoretic property of the Leibniz operator restricted to deductive filters of ${\cal L}$. This result was previously known for equational definability without parameters. Similarly, it was known that the truth sets of $Mo{d^{\rm{*}}}{\cal L}$ are implicitly definable if and only if the Leibniz operator is injective on deductive filters of ${\cal L}$ over every algebra. However, it was an open problem whether the injectivity of the Leibniz operator transfers from the theories of ${\cal L}$ to its deductive filters over arbitrary algebras. We show that this is the case for logics expressed in a countable language, and that it need not be true in general. Finally we consider an intermediate condition on the truth sets in $Mo{d^{\rm{*}}}{\cal L}$ that corresponds to the order-reflection of the Leibniz operator.