Diagonal Array Research Articles

O-119 Architecture and in situ arrangement of the CatSper-channel complex in the sperm flagellum

Abstract The sperm calcium channel CatSper plays a central role in successful fertilization as a primary Ca2+ gateway. Here, we applied cryo-electron tomography to visualize the higher-order organization of the native CatSper complex in intact mammalian sperm. The repeating CatSper units form long zigzag-rows along mouse and human sperm flagella. Above each tetrameric channel pore, most of the extracellular domains form a canopy that interconnects to a zigzag-shaped roof. Murine CatSper contains an additional wing-structure connected to the tetrameric channel. The intracellular domains link two neighboring channels to a diagonal array, suggesting a dimer formation. Fitting of an atomic model of isolated monomeric CatSper to the in situ map reveals supramolecular interactions and assembly of the CatSper complex. Loss of EFCAB9-CATSPERζ alters the architecture and interactions of the channels, resulting in fragmentation and misalignment of the zigzag-rows and disruption of flagellar movement in Efcab9−/− sperm. This work offers unique insights into the structural basis for understanding CatSper regulation of sperm motility.

High-Speed CNN Accelerator SoC Design Based on a Flexible Diagonal Cyclic Array

The latest convolutional neural network (CNN) models for object detection include complex layered connections to process inference data. Each layer utilizes different types of kernel modes, so the hardware needs to support all kernel modes at an optimized speed. In this paper, we propose a high-speed and optimized CNN accelerator with flexible diagonal cyclic arrays (FDCA) that supports the acceleration of CNN networks with various kernel sizes and significantly reduces the time required for inference processing. The accelerator uses four FDCAs to simultaneously calculate 16 input channels and 8 output channels. Each FDCA features a 4 × 8 systolic array that contains a 3 × 3 processing element (PE) array and is designed to handle the most commonly used kernel sizes. To evaluate the proposed CNN accelerator, we mapped the widely used YOLOv5 CNN model and evaluated the performance of its implementation on the Zynq UltraScale+ MPSoC ZCU102 FPGA. The design consumes 249,357 logic cells, 2304 DSP blocks, and only 567 KB BRAM. In our evaluation, the YOLOv5n model achieves an accuracy of 43.1% (mAP@0.5). A prototype accelerator has been implemented using Samsung’s 14 nm CMOS technology. It achieves 1.075 TOPS, a peak performance with a 400 MHz clock frequency.

Study of crack propagation in multi-phase composites embedded with both stiff and compliant particles using phase field method

Abstract Crack propagation in two-phase particle-reinforced composites is extensively studied using
the phase field method. Typically, the particle either has a higher stiffness(stiff) or a lower
stiffness(compliant) than the matrix. However, the crack propagation in multi-phase composites
with both the stiff and compliant particles is not yet understood well. In this work, we report
on the crack propagation characteristics and the resulting enhanced effective fracture toughness
in multi-phase composite materials with both stiff and compliant particles using the phase filed
method. Three different geometric arrangements of particles are considered: a diagonal array,
a cubic array, and a honeycomb array. The honeycomb configuration had the best combination
of strength and effective fracture toughness. We show that apart from the local geometric
arrangement of the individual particles, the ratio of the stiffness of the individual particles is
an important factor in crack propagation. Furthermore, we show that the ratio of the critical
energy release rate of the individual particles can be tuned to increase the effective fracture
toughness.

Wideband design and modeling of efficient multi-resonance reflective linear-to-circular polarization converter

Abstract A reflective linear-to-circular polarization converter based on dual frequency-selective structures (FSSs) is proposed and modeled to exhibit efficient wideband performance. The design utilizes a diagonal array of two connected circular patches as an effective anisotropy with regular current distribution in several successive resonances, resulting in orthogonal reflections with a 90° phase difference. The relevant upper-part characteristic is improved by using two separate square patches as a high-frequency resonator. This design with distinct key parameters leads to high overlapping and then excellent bandwidth and efficiency over 105% and 96%, respectively, with an axial ratio below 1.7 dB. A sophisticated equivalent circuit-admittance model including effective mutual coupling between two FSSs is extracted, featuring closed-form equations for the physical design. Different dielectric constants are studied on the converter, which offer controllable coverage in the range of 3–24 GHz (S, C, X, Ku, and K bands), variably. For actual validation, a very thin (0.04λ0 at 3.65 GHz) 8 × 8 array prototype was built and measured at different incident angles, showing angular stability up to 45° in 78% (6–14 GHz) bandwidth. This converter has potential applications in communication, spectroscopy, detection, and imaging in micro-, mm-, and THz-wave regions.

Mirror-based multimodal straightforward method for impedance eduction using a zigzag array

The Mirror-based Multimodal StraightForward Method (MM-SFM) is proposed herein to realize accurate and reliable liner impedance eduction covering the wide frequency range of aeroengine fan noises. It adopts a novel zigzag array in the flow duct, and unfolds them by a coordinate transformation into a mapping diagonal array in an extended duct, which can increase the array transverse spacing Δz considerably. Then, it invokes the M-SFM incorporating the trust-region and extended Prony's algorithms, to decompose the three-dimensional multimodal aeroacoustic field and educe the impedance. A parametric study based on the Monte-Carlo uncertainty analysis is conducted through finite-element numerical experiments on a 51 × 51 mm2 flow duct, to survey the method performance under random perturbations. It indicates that, the educing accuracy and reliability are promoted by increasing Δz or the axial spacing Δx properly, and the decomposed-mode number M×N=10 is appropriate herein. In our studied cases, using the recommended array of Δz=25.5mm and Δx=22mm locating at the nodes of transverse mode m = 2, the MM-SFM generally produces accurate averaged educed impedances in a considerably extended frequency range from 100 Hz up to nearly 10 kHz, and has small educing uncertainties at most absorptive frequencies and thus a good reliability.

Impedance eduction experiments covering higher frequencies based on the multimodal straightforward method

The multimodal straightforward method is developed further, validated and applied experimentally. The trust-region algorithm is introduced to reduce the eduction time, a flow duct setup with a cross section of 51 × 51 mm2 is built for the impedance eduction, and several single- and multi-layer perforated liners are tested from 0.5 kHz up to 6.0 kHz at two average Mach numbers under several types of modal sound sources. It is validated that, this method, by utilizing a diagonal microphone array and improving Prony’s algorithm, enables the automatic match between axial and transverse wavenumbers, and thus realizes the full decomposition to three-dimension multimodal sound fields. By introducing the trust-region algorithm, it can educe the impedance with a good consistency and a higher time efficiency. Generally, this method is applicable to the practical impedance eduction in multimodal aeroacoustic environments on a real flow duct, with the upper frequency extended from 3.0 to 6.0 kHz covering the main frequency range of aeroengine fan noises. For multilayer liners, the educed impedance spectrum is considerably flatter than the prediction by an existing impedance model in some cases especially near the antiresonance, and the grazing flow magnifies such a flatting trend accompanied by more evident predicting deviations. The spectra of educed impedance and transmission loss show that the multilayer liner possesses more resonant frequencies within the concerned range and broadband absorption potentials if well designed.

CNN Accelerator Using Proposed Diagonal Cyclic Array for Minimizing Memory Accesses

CNN Accelerator Using Proposed Diagonal Cyclic Array for Minimizing Memory Accesses

3D structure and in situ arrangements of CatSper channel in the sperm flagellum

The sperm calcium channel CatSper plays a central role in successful fertilization as a primary Ca2+ gateway. Here, we applied cryo-electron tomography to visualize the higher-order organization of the native CatSper complex in intact mammalian sperm. The repeating CatSper units form long zigzag-rows along mouse and human sperm flagella. Above each tetrameric channel pore, most of the extracellular domains form a canopy that interconnects to a zigzag-shaped roof. Murine CatSper contains an additional wing-structure connected to the tetrameric channel. The intracellular domains link two neighboring channels to a diagonal array, suggesting a dimer formation. Fitting of an atomic model of isolated monomeric CatSper to the in situ map reveals supramolecular interactions and assembly of the CatSper complex. Loss of EFCAB9-CATSPERζ alters the architecture and interactions of the channels, resulting in fragmentation and misalignment of the zigzag-rows and disruption of flagellar movement in Efcab9−/− sperm. This work offers unique insights into the structural basis for understanding CatSper regulation of sperm motility.

Large-angle polarization insensitive negative refraction in the diagonal array photonic crystal

In this article, the all-angle and polarization insensitive negative refraction (NR) properties are investigated in a 2D diagonal array photonic crystal. The rod-type structure presents the all-angle NR for TM2 in a bandwidth of Δω/ωc ∼ 20%. The all-angle NR does not hold for the hole-type structure due to the overlap of the 2nd and the 3rd bands, however, the polarization insensitive negative refraction is achieved for incidence angles of over θin = ±20° in a bandwidth of Δω/ωc = 10.6% in the second band. The proposed structure has been investigated using the PWE and the FDTD methods, regarding fabrication challenges in Si technology for the central operating wavelength of λc = 1550 nm.

Performance Degradation Due to Nonlocal Heating Effects in Resistive ReRAM Memory Arrays

ABSTRACTFrequent switching of resistive memory cell may lead to a local accumulation of Joules heat in the device. Since the ReRAM cells are arranged in crossbar arrays with the two electrodes running perpendicular to each other, the heat generated in one device spreads via common electrode metal lines to the neighboring cells causing their performance degradation. Also cells that do not share any of the two electrodes (e.g. the diagonal array cells) with the hot device may also degrade provided the intermediate cells are set to an on-state establishing thus a continuous thermal conduction path between the heated and the probed device. It is found that the heat conduction along the active Cu electrode is more pronounced than that along the inert Pt electrode. Devices with Rh inert electrode performed better than those with Pt electrode due to better heat conductivity properties of Rh vs Pt. The heat dissipation is also found worse for a heated device with narrow and thin lines causing, however less degradation of more distant neighbor cells than for wide and thick metal lines. Finally, there is a trade-off between dissipating the heat quickly form the heated device to increase its maximum switching cycles and the heat exposure of the neighboring devices.

Effect of the FRP sheet's arrays and NSM FRP bars on in-plane behavior of URM walls

This paper studies the results of compression diagonal tests conducted on a series of retrofitted and non-retrofitted small-scale masonry walls (which are also known as wallettes). Wallettes with the same characteristics and mechanical properties of large masonry walls were retrofitted by using two arrays of glass fiber reinforcement polymer (GFRP) sheets (grid and diagonal), two arrays of carbon fiber reinforcement polymer (CFRP) sheets (grid and diagonal), and near surface mounted bars (steel and GFRP). FRP sheets were applied to both surfaces of the wallettes, and rebar was mounted onto one of the surfaces in two horizontal and two vertical arrangements. All of the methods significantly increased loading capability and ductility of wallettes. Wallettes retrofitted with near surface GFRP bars had the highest value of final load, and specimens retrofitted with CFRP sheets in a diagonal array demonstrated the highest ductility among all tested specimens. Wallettes retrofitted with near surface mounted steel bars showed poor performance in terms of both loading capability and ductility. This study also includes discussion of failure modes, elastic characteristics, shear stresses and strains, and other variables that impact retrofitting.

Influence of the Design of Square p+ Islands on the Characteristics of 4H-SiC JBS

A novel diagonal square array junction barrier Schottky (JBS) diode is created to enhance the forward current and reverse breakdown voltage by increasing the Schottky contact area and shortening the diagonal spacing between two adjacent p+ islands in the active area of a JBS diode. The shape of the p+ islands is square and the positional arrangement of the p+ islands is a diagonal array. Half of the upper and lower p+ islands with smaller areas are connected with the innermost p+ guard ring to create more Schottky contact area and laterally extend the electric field to the edge termination. Results show that the forward current density and reverse breakdown voltage for the diagonal square array JBS diode are 4.2% and 10.7% higher than those for the conventional square array JBS diode, respectively. As the spacing increases, the breakdown voltage for the diagonal square array JBS diode and the conventional square array JBS diode decrease by 3.5% and 7.3%, respectively, indicating that the diagonal square array JBS has more uniform depletion regions and electric field to retain the breakdown voltage.

Design, fabrication and measurement of a microchannel heat sink with a pin-fin array and optimal inlet position for alleviating the hot spot effect

A microchannel heat sink with an inlet near the midpoint of the diagonal and high aspect ratio micro pin-fin array was designed, fabricated and measured. The heat transfer performance of the microchannel heat sink was simulated by a computational fluid dynamics (CFD) method. The inlet near the midpoint of the diagonal was proposed to alleviate the hot spot effect. The maximum temperature of the chip was reduced by up to 26.7% at a dissipation power of 72 W compared with other reference inlet/outlet configurations. Other parameters of the micro pin fins, such as the height, the spacing distance and the edge length, were optimized for improving heat transfer capacity. The microchannel heat sink prototype sample was fabricated and tested through UV-LIGA technology and an infrared thermal imaging system, respectively. The convective heat transfer increased at high flow rates (40 ml min−1~90 ml min−1), which resulted in a gradually increasing deviation between simulation and experiment. The measurement results show that the maximum dissipation heat flux can reach 209 W cm−2 when the chip maximum temperature is under 85 °C at a flow rate of 90 ml min−1. It is shown that the optimization of inlet position and micro pin-fin geometrical topology give the microchannel heat sink the potential to remove high heat flux.

Vortex Doping Into Superconducting ${\rm Mo}_{80}{\rm Ge}_{20}$ Square Network

We have fabricated the finite-sized amorphous Mo <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">80</sub> Ge <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">20</sub> superconducting networks with 10×10 square holes and directly observed the vortex structures by means of using the scanning SQUID microscope. On the increase of the field in a stepwise manner, the vortex penetration into the network is likely to follow the Bean critical model, wherein vortices first enter the network from the edges and penetrate deeper toward the center of the network as the field increases. We observed that the evolution of vorticity mainly occurred along the diagonal direction of the network, which has a narrow wire compared with the hole size. The vortex pattern was strongly modified as the system was cooled down below T <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">c</sub> . A diagonal vortex array appeared at intermediate temperatures, and is transformed into the isolated vortices at lower temperatures due to the strong repulsive interaction between vortices.

Computational Study of the Blood Flow in Three Types of 3D Hollow Fiber Membrane Bundles

The goal of this study is to develop a computational fluid dynamics (CFD) modeling approach to better estimate the blood flow dynamics in the bundles of the hollow fiber membrane based medical devices (i.e., blood oxygenators, artificial lungs, and hemodialyzers). Three representative types of arrays, square, diagonal, and random with the porosity value of 0.55, were studied. In addition, a 3D array with the same porosity was studied. The flow fields between the individual fibers in these arrays at selected Reynolds numbers (Re) were simulated with CFD modeling. Hemolysis is not significant in the fiber bundles but the platelet activation may be essential. For each type of array, the average wall shear stress is linearly proportional to the Re. For the same Re but different arrays, the average wall shear stress also exhibits a linear dependency on the pressure difference across arrays, while Darcy's law prescribes a power-law relationship, therefore, underestimating the shear stress level. For the same Re, the average wall shear stress of the diagonal array is approximately 3.1, 1.8, and 2.0 times larger than that of the square, random, and 3D arrays, respectively. A coefficient C is suggested to correlate the CFD predicted data with the analytical solution, and C is 1.16, 1.51, and 2.05 for the square, random, and diagonal arrays in this paper, respectively. It is worth noting that C is strongly dependent on the array geometrical properties, whereas it is weakly dependent on the flow field. Additionally, the 3D fiber bundle simulation results show that the three-dimensional effect is not negligible. Specifically, velocity and shear stress distribution can vary significantly along the fiber axial direction.

Three-dimensional spatial learning in hummingbirds

To date, most studies of spatial learning have been conducted in the horizontal plane, with few addressing animals' use of the vertical dimension. It is not clear, therefore, what difference adding a vertical component to the learning/memory of a spatial location makes. The aim of this study was to examine the learning by rufous hummingbirds, Selasphorus rufus, of a rewarded location in the vertical and horizontal axes. We found that their ability to learn the location of a rewarded flower in a linear flower array depended on its orientation and on the spacing distance between the flowers in the array. Birds chose the flower in the rewarded location more than any of the other four flowers in the horizontal array but only when flowers were spaced 30 cm apart. In contrast, in the vertical array or when the flowers were 5 cm apart horizontally, birds only avoided visiting the two distal flowers. In addition, the cues the birds used to learn the rewarded location depended on the spacing scale in the horizontal dimension: at 30 cm flower spacing, birds learned the absolute location whereas at 5 cm they chose the relative and absolute locations equally. In a diagonal linear array, birds chose the rewarded flower more than any other. When the array was oriented either vertically or horizontally for the test, the birds chose the flower in the same horizontal location as for the rewarded training location. The hummingbirds appear to favour the horizontal over the vertical component of a learned location.

A matrix-theoretic approach for analyzing quasi-cyclic low-density parity-check codes

A matrix-theoretic approach for studying quasi-cyclic codes based on matrix transformations via Fourier transforms and row and column permutations is developed. These transformations put a parity-check matrix in the form of an array of circulant matrices into a diagonal array of matrices of the same size over an extension field. The approach is amicable to the analysis and construction of quasi-cyclic low-density parity-check codes since it takes into account the specific parity-check matrix used for decoding with iterative message-passing algorithms. Based on this approach, the dimension of the codes and parity-check matrices for the dual codes can be determined. Several algebraic and geometric constructions of quasi-cyclic codes are presented as applications along with simulation results showing their performance over additive white Gaussian noise channels decoded with iterative message-passing algorithms.

Driven Brownian transport through arrays of symmetric obstacles

We numerically investigate the transport of a suspended overdamped Brownian particle which is driven through a two-dimensional rectangular array of circular obstacles with finite radius. Two limiting cases are considered in detail, namely, when the constant drive is parallel to the principal or the diagonal array axes. This corresponds to studying the Brownian transport in periodic channels with reflecting walls of different topologies. The mobility and diffusivity of the transported particles in such channels are determined as functions of the drive and the array geometric parameters. Prominent transport features, like negative differential mobilities, excess diffusion peaks, and unconventional asymptotic behaviors, are explained in terms of two distinct lengths, the size of single obstacles (trapping length), and the lattice constant of the array (local correlation length). Local correlation effects are further analyzed by continuously rotating the drive between the two limiting orientations.

Use of Traditional Mask Images in Design Development for Fashion-Cultural Products

This paper developed motifs through the use of images of masks with which the Korean innate consciousness of aesthetics is expressed. The motifs were applied to fashion items. This paper investigated the concept, origin and types of traditional masks through the existing literature. Using the computer graphic programs of Illustrator and Photoshop CS2, three basic motifs were set from the images of the nobleman, Bune of Hahoi Tal and Byeongsan Tal. Each motif was extended into two motifs by changing shape and color. For the basic motif design, this study sought to express contemporary images, suitably for each fashion item, while maintaining the basic shape of the masks and their traditional images. In addition, this study set the concept of the design so that could be accepted by various age groups. For the design of handkerchiefs, a rotating array, involving enlargement, reduction, repetition, and the gradation of motifs, as well as a diagonal symmetric array, and all-over patterns were developed. The T-shirt design created here was divided into a half-sleeve box type, a round neckline sleeveless type, a V-neckline close-fitting sleeveless type, and a V-neckline close-fitting cap sleeve type. For the design of necklaces, OLED or LED, which are considered as a future display type, was used. Additionally, the production of an entertainment styled new atmosphere is proposed.

Heat transfer mediated by coronary circulation in Langendorff-perfused isolated whole hearts

Although coronary flow is essential for oxygen supply, which is a prerequisite for cardiac electrical activity, energy metabolism and mechanical performance, the roles of coronary circulation on heat transfer to the heart have received less attention. This study investigated the effects of coronary circulation on epicardial temperature, the effects of temperature on coronary resistance, and the effects of ischemia on temperature fall, using isolated perfused rat or guinea pig hearts. Monophasic action potential (MAP) and epicardial temperature were recorded by a pair of suction electrodes and thermisters, while whole heart conductance (WHC) was estimated by a two-electrode instrument arranged in a diagonal array, under the alteration of the coronary flow rate of perfusate with different temperatures. MAP duration was sensitive to the local temperature, and lowering the temperature caused reduced WHC and increased coronary resistance calculated by dividing perfusion pressure by flow rate. After the onset of ischemia, WHC fell immediately in a single exponential manner, and MAP duration was abbreviated after transient behaviors explained well by the exquisite temperature gradient governed by coronary artery geometry. Epicardial temperature is maintained by coronary circulation in isolated perfused heart. Temperature-sensitive coronary tonus and MAP duration indicate that an exquisite temperature gradient underlies inhomogeneous distributions of coronary flow and electrical property. No-flow ischemia disturbs heat transfer and augments the temperature gradient transiently. Therefore, an isolated perfused heart can be considered as a heat transfer model where thermoregulation is maintained by warm coronary perfusion.