Pairwise Meta-Modeling of Multivariate Output Computer Models Using Nonseparable Covariance Function

<div><p></p><p>The Gaussian process (GP) model is a popular method for emulating deterministic computer simulation models. Its natural extension to computer models with multivariate outputs employs a multivariate Gaussian process (MGP) framework. Nevertheless, with significant increase in the number of design points and the number of model parameters, building a MGP model is a very challenging task. Under a general MGP model framework with nonseparable covariance functions, we propose an efficient meta-modeling approach featuring a pairwise model building scheme. The proposed method has excellent scalability even for a large number of output levels. Some properties of the proposed method have been investigated and its performance has been demonstrated through several numerical examples. Supplementary materials of this paper are available online. </p></div

Combinatorial Study of Ceramic Tape-Casting Slurries

Ceramic tape-casting slurries are complex systems composed of ceramic powder, solvent, and a number of organic components. Conventionally, the development of ceramic tape-casting slurries is time-consuming and of low efficiency. In this work, combinatorial approaches were applied to screen the ethanol and ethyl-acetate binary solvent based slurry for ceramic green tape-casting. The combinatorial libraries were designed considering the variation of the amount of PVB (Poly vinyl-butyral) binder, polyethylene-400, and butyl-benzyl-phthalate plasticizers, and glyceryl triacetate dispersant. A parallel magnetic stirring process was used to make the combinatorial slurry library. The properties mapping of the slurry library was obtained by investigating the sedimentation and rheological characteristics of the slurries. The slurry composition was refined by scaling up the experiments and comparing the microstructure, mechanical property, and sintering behavior of green tapes made from the selected slurries. Finally, a kind of ethanol-ethyl acetate binary solvent based slurry system suitable for making X7R dielectric ceramic green tapes was achieved

Pairwise Estimation of Multivariate Gaussian Process Models With Replicated Observations: Application to Multivariate Profile Monitoring

<p>Profile monitoring is often conducted when the product quality is characterized by profiles. Although existing methods almost exclusively deal with univariate profiles, observations of multivariate profile data are increasingly encountered in practice. These data are seldom analyzed in the area of statistical process control due to lack of effective modeling tools. In this article, we propose to analyze them using the multivariate Gaussian process model, which offers a natural way to accommodate both within-profile and between-profile correlations. To mitigate the prohibitively high computation in building such models, a pairwise estimation strategy is adopted. Asymptotic normality of the parameter estimates from this approach has been established. Comprehensive simulation studies are conducted. In the case study, the method has been demonstrated using transmittance profiles from low-emittance glass. Supplementary materials for this article are available online.</p

Assessment of dental ontogeny in late Miocene hipparionines from the Lamagou fauna of Fugu, Shaanxi Province, China

<div><p>A collection of 28 hipparionine skull and mandible fossils with a dated age of approximately 7.4 Ma from Fugu, Shaanxi, northwestern China (belonging to <i>Hipparion chiai</i> and <i>Hipparion</i> cf. <i>coelophyes</i>) shows an age distribution in a successive development sequence. By observing the dentitions in these fossil materials, knowledge of dental ontogeny has been gained, such as the opening time of the posterior wall of post-fossettes, the displacement of the plis hypostyle, the morphologic changes of the protocone and hypocone, etc. Additionally, 4 isolated maxillary cheek teeth and 2 mandibular cheek teeth were cut into slices in the traditional manner for authentication. These discoveries indicate that both of the hipparionine species in the Lamagou fauna are <i>Hipparion</i> cf. <i>chiai</i> exactly and offer further insight into the morphologic changes that occur during dental wear in hipparionines, which may greatly promote the morphological and taxonomic study of hipparionine species.</p></div

The main ontogenetic laws of mandibular cheek tooth.

<p>The main ontogenetic laws of mandibular cheek tooth.</p

Isolated maxillary tooth NWU1475.8 (P3).

<p>(A) photo of step sections of NWU1475.8 (P3); (B) color line diagram of step sections of NWU1475.8 (P3); (C) lateral view of NWU1475.8 (P3).</p

Isolated mandibular tooth NWU1475.12 (m1 or m2).

<p>(A) photo of step sections of NWU1475.12 (m1 or m2); (B) color line diagram of step sections of NWU1475.12 (m1 or m2); (C) lateral view of NWU1475.12 (m1 or m2).</p

Ontogenetic sequences of the mandibular dentitions of <i>Hipparion</i> cf. <i>coelophyes</i>.

<p>(A) NWU1441; (B) NWU1426.2; (C) NWU1442; (D) NWU1443; (E) NWU1440.1; (F) NWU1439; (G) NWU1444; (H) NWU1445.</p

Isolated maxillary tooth NWU1475.7 (P2).

<p>(A) photoof step sections of NWU1475.7 (P2); (B) color line diagram of step sections of NWU1475.7 (P2); (C) lateral view of NWU1475.7 (P2).</p

CT reconstruction images of the inlaid maxillary cheek teeth.

<p>(A) NWU1420; (B) NWU1421; (C) NWU1419; (D) NWU1425; (E) NWU1423.</p