Template‐Based Reconstruction of Surface Mesh Animation from Point Cloud Animation

In this paper, we present a method for reconstructing a surface mesh animation sequence from point cloud animation data. We mainly focus on the articulated body of a subject — the motion of which can be roughly described by its internal skeletal structure. The point cloud data is assumed to be captured independently without any inter‐frame correspondence information. Using a template model that resembles the given subject, our basic idea for reconstructing the mesh animation is to deform the template model to fit to the point cloud (on a frame‐by‐frame basis) while maintaining inter‐frame coherence. We first estimate the skeletal motion from the point cloud data. After applying the skeletal motion to the template surface, we refine it to fit to the point cloud data. We demonstrate the viability of the method by applying it to reconstruct a fast dancing motion     

Flexible Piezoelectric Acoustic Sensors and Machine Learning for Speech Processing

Flexible piezoelectric acoustic sensors have been developed to generate multiple sound signals with high sensitivity, shifting the paradigm of future voice technologies. Speech recognition based on advanced acoustic sensors and optimized machine learning software will play an innovative interface for artificial intelligence (AI) services. Collaboration and novel approaches between both smart sensors and speech algorithms should be attempted to realize a hyperconnected society, which can offer personalized services such as biometric authentication, AI secretaries, and home appliances. Here, representative developments in speech recognition are reviewed in terms of flexible piezoelectric materials, self-powered sensors, machine learning algorithms, and speaker recognition.     

Numerical study on cooling performance of hybrid micro-channel/micro-jet-impingement heat sink

Journal of Mechanical Science and Technology - This study explores the cooling performance associated with single-phase hybrid micro-channel/micro-jet-impingement cooling method. A parametric study...     

Effects of amplitude modulation on perception of wind turbine noise

Wind turbine noise is considered to be easily detectable and highly annoying at relatively lower sound levels than other noise sources. Many previous studies attributed this characteristic to amplitude modulation. However, it is unclear whether amplitude modulation is the main cause of these properties of wind turbine noise. Therefore, the aim of the current study is to identify the relationship between amplitude modulation and these two properties of wind turbine noise. For this investigation, two experiments were conducted. In the first experiment, 12 participants determined the detection thresholds of six target sounds in the presence of background noise. In the second experiment, 12 participants matched the loudness of modified sounds without amplitude modulation to that of target sounds with amplitude modulation. The results showed that the detection threshold was lowered as the modulation depth increased; additionally, sounds with amplitude modulation had higher subjective loudness than those without amplitude modulation.     

Two-step sintering technique for enhancing mechanical and oxygen permeation properties of dual-phase oxygen transport membranes

The present work involved the application of a two-step sintering (TSS) technique for typical Ce_0.9Gd_0.1O_2?δ–La_0.6Sr_0.4Co_0.2Fe_0.8O_3–δ (GDC–LSCF) composites and its effect on the microstructure and resultantly mechanical and O₂-permeating properties. The samples obtained by conventional sintering (CS) performed at 1100, 1250, and 1400 °C for 3 h exhibited maximum flexural strength and hardness values of 142 MPa and 8.71 GPa, respectively. However, the application of a TSS procedure produced fine-grained microstructures with improved mechanical properties. In particular, with the use of a typical 1250/1200 TSS protocol, increases of approximately 31 % and 7% in the flexural strength and hardness values, respectively, were observed compared to those obtained using the CS method. Moreover, thick-film (～ 60 μm) GDC–LSCF membrane prepared by tape casting and the TSS technique showed remarkably 1.5–2 times higher oxygen permeation flux than membrane sintered by CS method. The results are discussed and explained in detail.     

Luminescent and magnetic properties of cerium-doped yttrium aluminum garnet and yttrium iron garnet composites

Functional materials exhibiting magnetic and luminescent properties have been recognized as an emerging class of materials with great potential in advanced applications. Herein, properties of multifunctional ceramic composites consisting of two garnets, luminescent cerium-doped Y₃Al₅O₁₂ (Ce:YAG) and magnetic Y₃Fe₅O₁₂ (YIG), are reported. On increasing the sintering temperature, both the photoluminescence and saturation magnetization of the Ce:YAG-YIG composites decreased gradually because of the interdiffusion of trivalent ions such as Al³⁺ and Fe³⁺. At a constant sintering temperature of 1100?°C, the YIG contents in the composites increased, thereby causing their luminescent properties to degrade and the saturation magnetizations to increase. For application to electronics, Ce:YAG-YIG composite thin films were integrated on quartz substrates by sputtering the ceramic target. The composite thin films exhibited both magnetic and luminescent properties after annealing. These techniques facilitate the incorporation of multifunctional nanocomposites into various devices.     

Fabrication of Superjunction Trench Gate Power MOSFETs Using BSG‐Doped Deep Trench of p‐Pillar

In this paper, we propose a superjunction trench gate MOSFET (SJ TGMOSFET) fabricated through a simple p pillar forming process using deep trench and boron silicate glass doping process technology to reduce the process complexity. Throughout the various boron doping experiments, as well as the process simulations, we optimize the process conditions related with the p pillar depth, lateral boron doping concentration, and diffusion temperature. Compared with a conventional TGMOSFET, the potential of the SJ TGMOSFET is more uniformly distributed and widely spread in the bulk region of the n drift layer due to the trenched p‐pillar. The measured breakdown voltage of the SJ TGMOSFET is at least 28% more than that of a conventional device.