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In order to explore a novel material for thermal barrier coatings (TBCs), the composite ceramic materials of lanthanum zirconate (La 2 Zr 2 O 7 ) and lanthanum phosphate (LaPO 4 ) were prepared by calcining. The phases and micro-structures of La 2 Zr 2 O 7 /LaPO 4 composite ceramic materials were studied by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The properties of La 2 Zr 2 O 7 /LaPO 4 material, such as thermal conductivity, coefficient of thermal expansion (CTE) and mechanical properties of La 2 Zr 2 O 7 /LaPO 4 were investigated using laser flash method, high-temperature dilatometer and micro-hardness test. Based on XRD patterns, the pyrochlore and monazite phases were obtained in La 2 Zr 2 O 7 /LaPO 4 composite ceramic material without any chemical reaction. According to SEM morphology, the La 2 Zr 2 O 7 was closely near to LaPO 4 along with a lot of pores, it might cause the decrease of thermal conductivity. The thermal conductivities of composite ceramics were similar to that of La 2 Zr 2 O 7 . The CTE of them were about 10 × 10 − 6 K − 1 , which was close to the value of LaPO 4 . Because of doping LaPO 4 , hardness and Young's modulus of samples were lower than that of La 2 Zr 2 O 7 . The studies revealed that the La 2 Zr 2 O 7 /LaPO 4 composite ceramics had good mechanical and thermal physical properties and could be applied as new candidate materials for TBCs in the future. [ABSTRACT FROM AUTHOR]

Using a Chinese Word Associates Test (WAT-C), this study examined the vocabulary depth of second language learners of Chinese and its contribution to the learners' reading comprehension. Results showed no significant effects of word frequency, word class (i.e., adjectives vs. verbs), and type of association relationships (i.e., paradigmatic vs. syntagmatic) on learners' WAT-C performance. More important, vocabulary depth was found to be a significant and unique predictor of reading comprehension over and above vocabulary size. On the other hand, the relative contributions of vocabulary depth and size depended on what types of texts were read and what comprehension skills were assessed. Specifically, for the long passage comprehension task with questions testing literal comprehension, vocabulary size was a more important predictor, whereas for the short passage comprehension task with questions testing inferencing, vocabulary depth was a more important predictor. These findings were discussed in light of the different levels of lexical complexity between the short and long passages and the different cognitive processing demands the questions of the two comprehension tasks placed on learners. [ABSTRACT FROM AUTHOR]

This intervention study examined the effect of English morphological instruction on the development of English as well as Malay morphological awareness and word reading abilities among Malay–English bilingual fourth graders in Singapore, where English is the medium of instruction. The intervention group experienced semester-long instruction in English derivation; the control group was taught with their regular English curriculum. Both groups were tested with derivational awareness and derived word decoding tasks in English and Malay at the end of Grade 3 prior to the intervention (pre-test) and at the end of the first semester of Grade 4 right after the intervention (post-test). There was no significant difference between the two groups on all tasks at pre-testing. Significant intervention effects were found on the development of English abilities in that the intervention group's performance gain was significantly greater than that of the control group on all English tasks except the derived decoding fluency task. More important, such intervention effects were also evident with some Malay tasks. These findings provide empirical evidence that supports the benefits of morphological instruction to bilingual children's reading development and a possibly causal effect of cross-linguistic transfer of morphological awareness from English to Malay. [ABSTRACT FROM AUTHOR]

This longitudinal study examined the contribution of morphological awareness to bilingual word learning of Malay-English bilingual children in Singapore where English is the medium of instruction. Participants took morphological awareness and lexical inference tasks in both English and Malay twice with an interval of about half a year, the first time at the end of Grade 3 (Time 1) and the second time at the end of the first semester of Grade 4 (Time 2). Structural equation modeling (SEM) analyses revealed that within both languages, morphological awareness significantly predicted lexical inference at Time 1 as well as Time 2, and the contribution also became strengthened over time. Cross-linguistic SEM analyses showed that concurrently at both Time 1 and Time 2, English morphological awareness only had a significant indirect effect on Malay lexical inference. The exact indirect relationships, however, varied between Time 1 and Time 2. In addition, an indirect effect of Time 1 English morphological awareness on Time 2 Malay lexical inference also surfaced. These findings suggest concurrent as well as longitudinal cross-linguistic transfer of morphological awareness from English to Malay. [ABSTRACT FROM AUTHOR]

Background: Neuroblastoma is one common pediatric malignancy notorious for high temporal and spatial heterogeneities. More than half of its patients develop distant metastases involving vascularized organs, especially the bone marrow. It is thus necessary to have an economical, noninvasive method without much radiation for follow‐ups. Radiomics has been used in many cancers to assist accurate diagnosis but not yet in bone marrow metastasis in neuroblastoma. Methods: A total of 182 patients with neuroblastoma were retrospectively collected and randomly divided into the training and validation sets. Five‐hundred and seventy‐two radiomics features were extracted from magnetic resonance imaging, among which 41 significant ones were selected via T‐test for model development. We attempted 13 machine‐learning algorithms and eventually chose three best‐performed models. The integrative performance evaluations are based on the area under the curves (AUCs), calibration curves, risk deciles plots, and other indexes. Results: Extreme gradient boosting, random forest (RF), and adaptive boosting were the top three to predict bone marrow metastases in neuroblastoma while RF was the most accurate one. Its AUC was 0.90 (0.86–0.93), F1 score was 0.82, sensitivity was 0.76, and negative predictive value was 0.79 in the training set. The values were 0.82 (0.71–0.93), 0.80, 0.75, and 0.92 in the validation set, respectively. Conclusions: Radiomics models are likely to contribute more to metastatic diagnoses and the formulation of personalized healthcare strategies in clinics. It has great potential of being a revolutionary method to replace traditional interventions in the future. [ABSTRACT FROM AUTHOR]

This paper develops a new health assessment method based on belief rule base with sliding time window considering correlation and redundancy of input information (BRB-WCR). The new proposed method aims to solve four problems in health assessment of dynamic complex system: lack of system fault data, uncertainty of expert knowledge, correlation of characteristic and high real-time requirement of system. The traditional BRB model can address the first two problems while it assumes that the input characteristics are completely independent. In order to solve the two remaining problems, a new BRB-WCR model is developed, where the correlation and redundancy of characteristics are considered and the sliding time window for online training data is introduced to improve the real time performance of the model. Moreover, to address the uncertainty of expert knowledge, a new optimization model is developed to train the parameters of the BRB-WCR model. To illustrate the effectiveness of the developed method, a case study of inertial navigation platform is conducted. • A new BRB-WCR model with considering correlation and redundancy of characteristics. • The sliding time window for online training data. • A new health assessment method based on BRB-WCR for dynamic complex system. • Optimization model for sliding time window and model parameters. [ABSTRACT FROM AUTHOR]

This study examined how the properties of semantic radicals affect character meaning inference among adult learners of Chinese as a foreign language (CFL). A semantic radical is a component of a compound character whose primary function is to provide an aspect of the meaning of its host character. Because radicals differ in the nature of the information they supply and their relationships with the characters' meaning, their functions are not uniformly salient to users. This study focused on the notion of radicalfunctional salienceand its impacts on character learning and processing. In Study 1, we identified radical properties pertinent to functional salience via a sequence of property analyses, and determined how the identified properties were related to perceived familiarity with commonly used radicals among native Chinese speakers. Based on the analyses, in Study 2, we examined how functional salience affects the way CFL learners use radical information through character meaning extraction and inference tasks. The results demonstrated that functional salience was differentially related to performance variances. The findings suggest that CFL learners' use of radical information during character processing is explained jointly by the properties of semantic radicals and learners' radical knowledge. [ABSTRACT FROM PUBLISHER]

Empirical Mode Decomposition (EMD) has proved to be an effective and powerful analytical tool for non-stationary time series and starts to exhibit its modeling potential for 3D geometry analysis. Yet, existing EMD-based geometry processing algorithms only concentrate on multi-scale data decomposition by way of computing intrinsic mode functions. More in-depth analytical properties, such as Hilbert spectra, are hard to study for 3D surface signals due to the lack of theoretical and algorithmic tools. This has hindered much more broader penetration of EMD-centric algorithms into various new applications on 3D surface. To tackle this challenge, in this paper we propose a novel and efficient EMD and Hilbert spectra computational scheme for 3D geometry processing and analysis. At the core of our scheme is the strategy of dimensionality reduction via space-filling curve. This strategy transforms the problem of 3D geometry analysis to 1D time series processing, leading to two major advantages. First, the envelope computation is carried out for 1D signal by cubic spline interpolation, which is much faster than existing envelope computation directly over 3D surface. Second, it enables us to calculate Hilbert spectra directly on 3D surface. We could take advantages of Hilbert spectra that contain a wealth of unexploited properties and utilize them as a viable indicator to guide our EMD-based 3D surface processing. Furthermore, to preserve sharp features, we develop a divide-and-conquer scheme of EMD by explicitly separating the feature signals from non-feature signals. Extensive experiments have been carried out to demonstrate that our new EMD and Hilbert spectra based method is both fast and powerful for 3D surface processing and analysis. [ABSTRACT FROM AUTHOR]

S-136 (STAVAX ESR) steel has been widely applied in the mold manufacturing industry. Commercially available S-136 steel possesses high surface roughness, which exerts negative effects on the device performance. In this paper, S-136 steel surface planarization using chemical mechanical polishing (CMP) was investigated and the process parameters included down pressure, platen speed, slurry pH and abrasive category. The results demonstrated that the relationship of material removal rate (MRR) with respect to the multiply of pressure and platen speed was in accordance with a modified Preston equation: MRR = ( KP + B 0 ) V + R 0 . With the variation of pH, the MRR changed rapidly. Compared with initial root mean square (RMS) roughness of 37.47 nm, the ultra-smooth surface with RMS roughness 3.01 nm was obtained under optimized condition with MRR as high as 187 nm/min. Finally, optimized CMP process parameters for S-136 steel were proposed and its CMP mechanism was discussed in detail. [ABSTRACT FROM AUTHOR]