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Children Sustain Their Attention on Spatial Scenes When Planning to Describe Spatial Relations Multimodally in Speech and Gesture
No full textHow do children allocate visual attention to scenes as they prepare to describe them multimodally in speech and co-speech gesture? In an eye-tracking study, Turkish-speaking 8-year-old children viewed four-picture displays depicting the same two objects in different spatial relations as they prepared to describe target pictures depicting left-right relations. Children's visual attention was sustained on the target picture when they were planning descriptions that expressed the spatial relation multimodally in speech and gesture, but not unimodally in speech only. This pattern persisted regardless of the semantic relation between speech and gesture (i.e., for both complementary gestures that disambiguated speech and redundant gestures that supplemented already unambiguous speech). Importantly, visual attention patterns did not differ across description types while children were previewing the displays before message preparation. These results indicate that multimodal message preparation might place different demands on visual attention than unimodal message preparation, possibly due to the affordances of gestures for expressing spatial relations. Summary: We test the idea that the way children attend to spatial relations prior to communication is related to how they end up describing them. Children's attention was sustained on spatial scenes when they were planning multimodal spatial descriptions in speech and gesture, but not unimodal descriptions in speech only. Planning multimodal descriptions was associated with sustained attention on the spatial scenes regardless of the semantic relation between speech and gesture
Special Issue on High-Performance Computing Conference (BAŞARIM 2024)
No full textThis editorial is for the Special Issue on the 8th High-Performance Computing Conference (BAŞARIM 2024), held on May 15–17, 2024, at the Middle East Technical University Culture and Convention Center in Ankara
Efficient utilization of streaming multiprocessors for the implementation of particle filter on graphics processing unit
No full textThe particle filter is a serial Monte Carlo estimation method. It is used in tracking applications in which the system or measurement model is highly nonlinear. The quality of the estimation improves as the number of particles increases; however, the computational cost also rises. The graphics processing units (GPUs) offer a promising solution for the particle filter by providing many cores in their architectures. To implement the particle filter on the GPU, we use CUDA as the parallel computing platform. The architecture of the GPU must be carefully considered when determining the parameters of CUDA kernels. Configuring the block size of CUDA kernels appropriately is essential for the efficient utilization of streaming multiprocessors (SMXs). In this study, we investigate the impact of block size on SMX efficiency, particularly in GPUs where the number of SMXs is not a power of two. We propose three distinct scenarios based on different block size configurations and provide a detailed discussion of the characteristics and resulting speedups of these scenarios. We conduct experiments on two different GPU boards, NVIDIA Tesla K20 and NVIDIA Tesla K40. In addition, we demonstrate a multi-GPU approach for the particle filter using these boards and discuss the associated challenges and resulting speedups in detail
Growth evolution in calcium carbonate microparticles involving mixed vaterite-aragonite structures
No full textCalcium carbonate (CaCO3) is a widely occurring mineral that is crucial to many natural and synthetic processes. CaCO3 crystallizes in three anhydrous polymorphs and often serves as a model system to study nucleation and growth phenomena. In this article, we employ coherent diffraction imaging coupled with wide-angle x-ray diffraction (CXDI-WAXD) to investigate the three-dimensional (3D) morphology and crystal structure of CaCO3 microparticles crystallized under different reaction temperatures. We report particles containing both vaterite and aragonite, which we interpret as an intermediate growth stage between early vaterite and later aragonite formation. The results are based on the density variations observed in the 3D tomographic CXDI images, x-ray diffraction, and focussed ion beam-transmission electron microscopy study of the mixed vaterite-aragonite microparticles. A computational study based on Monte Carlo and molecular dynamics energy minimization was used to identify the small energetic variations between the different crystalline forms of CaCO3. The results presented in this article provide a better understanding of the morphology-structure correlation for CaCO3 polymorphs, depicting a transitional stage where both vaterite and aragonite coexist
The Routledge Companion to Comparative International Planning
No full textThis introductory chapter elaborates the rationale for collating an overview of international comparative planning as a field of work important to urban and regional planning and related built environment disciplines. Firstly, the editors situate recent research and planning practice activities in a broad history and past literature. Secondly, the chapter delves into the interpretation of relevant key terms, such as international, planning, comparative, and research as used in the context of this volume. This contextualisation illustrates tensions and differences between approaches to comparative work depending on the motivations that underlie the comparison in the first place, and hence offering valuable insights into the current state-of-play in the field. Thirdly, the chapter reviews the content and structure of the volume which comprises 7 parts and 37 chapters in total
Terahertz frequency-domain characterization of UHMW-PE ballistic armor plates
No full textUltra-high molecular weight polyethylene (UHMW-PE) fiber-based ballistic armor plates are analyzed in the terahertz (THz) frequency region to better understand their structural properties. Various thickness plates are produced by hot pressing 5, 10 and 15 layer four-ply cross-weaved UHMW-PE fiber sheets whose refractive index and absorption characteristics are then examined for three different frequencies using time-domain imaging techniques. The obtained transmission images reveal significant structural information, including surface texture and potential defects, such as air bubbles or voids. It is found that with an increasing number of layers in each plate there is an increase in the refractive index approaching the value of the UHMW-PE fiber sheet. The change in the effective refractive index is attributed to inhomogeneities such as bunching up of the fibers as well as voids because of the manufacturing processes with a larger inhomogeneity in the 5-layer plates as compared to the 10-and 15-layer plates. Furthermore, a significant change in refractive index is observed for different orientations of the armor plate with respect to the input beam polarization due to the presence of periodic surface ridge formations. A detailed analysis of the extinction coefficient with respect to the refractive index shows groupings in the range of values for different thickness plates which can serve as an indicator of the inhomogeneities inside the structures. The purely frequency domain analysis performed here suggests that such methods in the THz region can offer a new, rapid way for non-destructive analysis of ballistic armor plates
A local correlation-based algebraic transition model in k-ω SST formulation
No full textA new correlation-based algebraic transition model using local variables is proposed. Instead of solving an additional transport equation for intermittency, the model employs an intermittency function that controls the source terms of the turbulence model used. Thus, the model reduces the number of constants and functions needed, and achieves to solve problems by using less computational power compared to one-or two-equation transition models. The intermittency function of the present model is a more sophisticated modified version of that in the SA-BCM transition model, and it is coupled with the k-w SST turbulence model to eliminate the shortcomings in the SA-BCM model. The present model involves only four calibration constant, which are calibrated against the cases other than validation cases. The model is validated against a series of common flat plate experiments and four airfoil test cases. The results show a good agreement with the experiments and that the new model provides comparable success with more complicated transition models. Therefore, the present model provides an alternative means to include boundary layer transition effects in CFD simulations by reducing the number of constants and functions needed compared to that in other transition models
Multiscale Generalized Network Model Using Differential Micro-CT Imaging for Drainage in Heterogeneous Carbonates
No full textCapacity and IAPR Analysis for MIMO Faster-than-Nyquist Signaling with Small Acceleration Factors
No full textFaster-than-Nyquist (FTN) signaling is a non-orthogonal transmission technique offering a promising solution for future generations of communications. This paper studies the capacity of FTN signaling in multiple-input multiple-output (MIMO) channels for high acceleration factors. In our previous study [1], we found the capacity for MIMO FTN channels if the acceleration factor is larger than a certain threshold, which depends on the bandwidth of the pulse shape used. In this paper we extend the capacity analysis to acceleration factors smaller than this mentioned threshold. In addition to capacity, we conduct instantaneous-to-average power ratio (IAPR) analysis and simulation for MIMO FTN for varying acceleration factors for both Gaussian and QPSK symbol sets. Our analysis reveals important insights about transmission power and received signal-to-noise ratio (SNR) variation in FTN. As the acceleration factor approaches 0, if the transmission power is fixed, the received SNR diminishes, or if the received SNR is fixed, IAPR at the transmitter explodes
HESITANT FUZZY LINGUISTIC MATRIX GAME AND ITS APPLICATION IN MCDM PROBLEM
No full text. This study focuses on how to establish a connection between game theory and decision making under an uncertain environment. To tackle this uncertainty, an expansion of the hesitant fuzzy set and linguistic term set, i.e., the hesitant fuzzy linguistic term set (HFLTS), is considered here. The HFLTS is an effective technique for addressing ambiguity or uncertainty in multiple criteria decision making (MCDM). MCDM is a technique of evaluating multiple criteria for the sake of selecting the best alternative. It is an emerging topic in game theory and decision making. Nowadays, researchers are paying more attention to MCDM games with HFLTS. Numerous MCDM techniques are presented in the literature, but very few studies take into account MCDM challenges by using game theoretic models to ascertain the decision makers' preferences and attribute weights. Our main objective is to build the methods for solving an HFLTS-MCDM game. First, we present a novel HFLTS distance measure. To address the hesitant fuzzy linguistic-MCDM game, three novel distance measures, namely HFL-TOPSIS, HFL-VIKOR, and lambda-fuzzy measure, are devised. The resulting outcomes from the three methodologies are compared and contrasted. To exhibit the viability and effectiveness of the suggested measures, we illustrate a real-world example. The numerical results depict that lambda-fuzzy measure is the most suitable approach to find the best alternative among the set of alternatives. Moreover, the Spearman correlation coefficient and p-value between HFL-VIKOR and lambda-fuzzy measure (0.574125and0.045893, respectively) demonstrate the validity and robustness of the results