To address the challenge of detecting internal defects in medium-thick titanium alloy laser welds, a combined simulation and experimental study on ultrasonic testing was conducted. A finite element model employing a 5 MHz shear wave angle transducer for inspecting titanium alloy welds was established. An ultrasonic testing system was developed, incorporating a DPR300 pulser-receiver (JSR Ultrasonics, Pittsford, NY, USA) and an MSO5204 oscilloscope (RIGOL, Suzhou, China), and was calibrated using standard reference blocks. The inspection results for four prefabricated internal defects at various depths demonstrated that all defects were effectively detected, with the minimum detectable equivalent defect size reaching 1 mm. The measured signal-to-noise ratio (SNR) averaged 17.6 dB, validating the high sensitivity of the proposed system. The mean absolute error for defect localization was 0.438 mm, achieving a positioning accuracy better than 0.5 mm. This study indicates that the pro-posed method enables effective detection and accurate localization of internal defects in titanium alloy laser welds, providing critical technical support for laser welding quality assessment.

Efficient compression of massive 3D point clouds remains challenging under limited storage and bandwidth. The Moving Picture Experts Group (MPEG) has developed the geometry-based point cloud compression (G-PCC) standard and is currently at the FDIS stage, referred to as Enhanced G-PCC. This paper proposes a novel inter prediction attribute coding based on the Region Adaptive Hierarchical Transform (RAHT) and entropy coding framework to enhance the coding efficiency. 1) <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Multi-Reference Frames</i>: A low-delay prediction architecture is introduced to improve temporal correlation utilization, which has not yet been explored in G-PCC inter RAHT attribute compression, with a lightweight motion-based switch to disable multi-reference prediction for large motion. 2) <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Occupancy Information Difference</i>: The inter eligibility based on occupancy information difference scheme is employed to select valid inter reference blocks, while hybrid prediction scheme based on occupancy information difference is further introduced to enhance prediction accuracy. 3) <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Correlation Entropy Coding</i>: A new entropy coder is developed to exploit the intrinsic correlation among color components. By jointly leveraging these techniques, the proposed method efficiently exploits spatial and temporal regularities of dynamic point clouds, achieving significant performance gains. Experimental results show that it outperforms the state-of-the-art Enhanced G-PCC reference software (TMC13-v31), with average coding gains of 3.17% for reflectance on the Cat3 dataset and 2.81%, 16.92%, and 12.21% for the Luma, Cb, and Cr components on the Cat2 dataset under MPEG common test conditions. The method, <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Occupancy Information Difference</i>, has already been adopted into the MPEG Enhanced G-PCC standard.

The article presents the development of an innovative shape of the APS hollow block based on a cuboid, made of a designed recycled concrete mixture with additives of SBR rubber granules of various fractions and PET flakes obtained from recycling giving the possibility to managing this waste and contributing to environmental protection. The newly designed shape of the concrete wall block makes it possible to build foundation and retaining walls easily and quickly. At the same time, the designed curvilinear through-holes and two grooves enable the blocks to be joined horizontally with one another in a so-called ‘locking’ manner, ensuring horizontal stability and making it possible to meet the requirements for traditional openwork wall blocks. A series of laboratory tests is presented on the basis of designed concrete mixtures with different percentages of additives in the form of recycled waste: SBR rubber granules of different fractions and PET flakes, followed by the production of an openwork block APS from the selected recycled concrete mixture, which was compared with the reference block Alfa.

Massive off-chip accesses in graphics processing units (GPUs) are the main performance bottleneck. We find that many writes are duplicate, and the duplication can be <monospace xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">inter-dup</monospace> and <monospace xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">intra-dup</monospace>. While <monospace xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">inter-dup</monospace> means different memory blocks are identical, and <monospace xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">intra-dup</monospace> means all the 4B elements in a line are the same. In this work, we propose a cache-assisted GPU memory deduplication architecture named cache-assisted GPU memory deduplicated (CMD) to reduce the off-chip accesses via utilizing the data duplication in GPU applications. CMD includes three key design contributions which aim to reduce the three kinds of accesses: 1) a novel GPU memory deduplication architecture that removes the <monospace xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">intra-dup</monospace> and <monospace xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">inter-dup</monospace> lines. We design several techniques to manage duplicate blocks, reducing massive off-chip writes; 2) we propose a cache-assisted read scheme to reduce the reads to duplicate data. When an L2 cache miss wants to read the duplicate block, if the reference block has been fetched to L2 and it is clean, we can copy it to the L2 missed block without accessing off-chip DRAM. As for the reads to <monospace xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">intra-dup</monospace> data, CMD uses the on-chip metadata cache to get the data; and 3) when a cache line is evicted, the clean sectors in the line are invalidated while the dirty sectors are written back. However, most read-only victims are rereferenced from DRAM more than twice. Therefore, we add a full-associate FIFO to accommodate the read-only (it is also clean) victims to reduce the rereference counts. Experiments show that CMD can decrease the off-chip accesses by 31.01%, reduce the energy by 32.78% and improve performance by 42.53%. Besides, CMD can improve the performance of memory-intensive workloads by 57.56%.

Traditional subtractive technology is rapidly losing significance with the advent of digital manufacturing technologies, which offer affordable machining with high accuracy and repeatability. Computer numeric controlled (CNC) machining has been around for a while; however, it has been costly to own one. Since the concept of CNC machining is now broadly understood and open-source software is available for control, designers can make use of available local materials to develop cheaper CNC machines. Hence, this presents the evaluation of the design and development of a one-square-meter CNC milling machine. The control was implemented on Arduino Uno, while open-source Universal G-code Sender (UGS) and G-code reference block library (GRBL) were used for the G-code generation and machine control, respectively. The built CNC was calibrated and tested on wood and plastic materials, and the resulting products were acceptable in accuracy up to ±0.02 mm in the first trial, but attained perfect accuracy by the third trial. Multiple tests repeatedly showed that accuracy was maintained. Since the machine is reconfigurable, future work entails automation and incorporating laser cutting capabilities into the machine.

Achieving scalable and decentralized blockchain systems: a filecoin-based solution to the blockchain trilemma

Global intra prediction (GIP), including intra-block copy and template matching prediction (TMP), exploits the global correlation of the same image to improve the coding efficiency. In Beyond VVC, TMP uses template matching to determine the reference blocks for efficient prediction. There usually exists an error between the coding block and reference blocks, caused by the content mismatch or the coding distortion of the reference blocks. We propose an enhancement over the reference blocks, namely enhanced GIP (EGIP). Specifically, we design an enhanced filter according to the templates of the coding block and the reference blocks, with the reconstructed template of the coding block as the label for supervised learning. To support different enhancements, we design two types of inputs, i.e., EGIP based on neighboring samples (N-EGIP) and EGIP based on multiple hypothesis references (M-EGIP). Experimental results show that, based on enhanced compression model (ECM) version 8.0, N-EGIP achieves BD-rate reductions of 0.37%, 0.42%, and 0.40%, and M-EGIP brings 0.34%, 0.37%, and 0.34% BD-rate savings for Y, Cb, and Cr components, respectively. A higher coding gain, 0.46%, 0.54%, and 0.52% BD-rate savings, can be achieved by integrating N-EGIP and M-EGIP together. Owing to the coding gain and small complexity increase, the proposed EGIP has been adopted in the exploration of Beyond VVC and integrated into its reference software.

The article is devoted to the issues of suppression of stray parameters influence at eddy current testing of soldered lap joints of electrical machines using a tangential eddy current probe. Among the main stray parameters the paper highlights the deviation of specific conductivity and geometrical parameters of both test blocks and reference blocks in the process of instrument calibration and estimating the soldering integrity of soldered lap joints. In order to increase the reliability of testing correction of measurement results is proposed using developed formulas based on measurements of specific conductivity and thickness of the soldered joint. The probe design implements a clamp and a block stop allowing suppression of the influence of the probe offset relative to the solder joint and reference block in the process of calibration and testing. The technique of determining the soldering integrity of soldered lap joints of current-carrying copper busbars of stator windings of electric machines is suggested.

A new granite-doped concrete block with 60 cm x 60 cm x 60 cm dimensions has been built at CENIEH, Burgos, Spain, for dosimetry calibration and cross-referencing purposes. Independent evaluations of the block’s gamma dose rate using passive Al2O3:C dosimeters and various field gamma spectrometer (NaI) probes produce consistent results of 1495 ± 51 μGy a-1 and 1514 ± 43 μGy a-1 (or 1537 ± 19 μGy a-1, depending on the evaluation procedure employed), respectively. Bulk radioelement concentrations calculated from field gamma spectrometry using the Windows method are as follows: K = 1.58 ± 0.08 %, U = 4.26 ± 0.28 ppm, and Th = 12.62 ± 0.72 ppm. This new block complements existing dosimetry reference materials accessible at other laboratories and is available for the broader trapped charge dating community to use for instrument calibration, reproducibility assessments and intercomparison studies.

ABSTRACT The growing demand for sustainable building materials has sparked renewed interest in blocks for construction, particularly when stabilized with natural fibers to enhance their mechanical properties. This study presents a systematic review conducted in the ScienceDirect and Scopus databases, covering publications from 2015 to 2025. The inclusion criteria considered experimental studies that analyzed adobe stabilized with plant fibers and reported their mechanical properties. A total of nine studies met the eligibility criteria. The fibers evaluated included straw, Hibiscus cannabinus, palm, neem, jute, seagrass, date palm, and pine needles. Overall, the addition of fibers improved mechanical performance. The best compressive strength result was obtained with neem fibers, showing a 35% increase compared to the reference block. For tensile strength, the most significant improvement was observed with palm fibers, resulting in a 19% increase compared to the control. These results confirm that controlled fiber incorporation improves adobe performance, particularly in terms of compressive and tensile strength, while maintaining its sustainable and low-cost characteristics. However, differences in soil types and experimental procedures between studies limit comparability, highlighting the need for standardized methodologies in future research.

MotivationThe Variant Call Format (VCF) is widely used in genome sequencing but scales poorly. For instance, we estimate a 150 000 genome VCF would occupy 900 TiB, making it costly and complicated to produce, analyze, and store. The issue stems from VCF’s requirement to densely represent both reference-genotypes and allele-indexed arrays. These requirements lead to unnecessary data duplication and, ultimately, very large files.ResultsTo address these challenges, we introduce the Scalable Variant Call Representation (SVCR). This representation reduces file sizes by ensuring they scale linearly with samples. SVCR’s linear scaling relies on two techniques, both necessary for linearity: local allele indices and reference blocks, which were first introduced by the Genomic Variant Call Format. SVCR is also lossless and mergeable, allowing for N + 1 and N + K incremental joint-calling. We present two implementations of SVCR: SVCR-VCF, which encodes SVCR in VCF format, and VDS, which uses Hail’s native format. Our experiments confirm the linear scalability of SVCR-VCF and VDS, in contrast to the super-linear growth seen with standard VCF files. We also discuss the VDS Combiner, a scalable, open-source tool for producing a VDS from GVCFs and unique features of VDS which enable rapid data analysis. SVCR, and VDS in particular, ensure the scientific community can generate, analyze, and disseminate genetics datasets with millions of samples.Availability and implementationhttps://github.com/hail-is/hail/.

In this article, we propose an efficient reference-based deep in-loop filtering method for video coding. Existing reference-based in-loop filters often face challenges in improving coding efficiency due to the difficulty in capturing relevant textures from the reference frames. Our method accurately predicts the texture of a reference block and uses this information to restore the current block. To achieve this, we develop a reference-to-current feature estimation module that conveys high-quality information from previously coded frames in the feature domain, thereby preventing loss of detail due to inaccurate prediction. Although a neural network is trained to restore a coded video frame to be similar to the current frame, their performance can significantly degrade when operating with various quantization parameters (QPs) and managing different levels of distortion. This problem becomes further severe in the reference-to-current feature estimation, in which QP values are applied differently to video frames. We address this problem by developing a QP-aware convolution layer with a small number of learnable parameters to generate reliable features and adapt to fine-grained adaptive QPs among consecutive frames. The proposed method is implemented into the versatile video coding (VVC) reference software, VTM version 10.0. Experimental results demonstrate that the proposed method improves coding performance significantly in VVC.

Abstract Optical Coherence Tomography (OCT) is a high-resolution imaging technique extensively used in various fields, including medical diagnosis. The presence of speckle noise significantly degrades the quality of OCT images. To address this, a novel denoising approach based on High-Order Singular Value Decomposition (HOSVD), along with saliency enhancement and Marchenko-Pastur (MP) truncation, has been proposed. Initially, the method leverages the weighted absolute distance based on variance and information entropy to locate non-local patches that are highly correlated with a given reference block. Following this, a three-dimensional tensor is decomposed via HOSVD and then contracted based on the principles from the MP theorem in random matrix theory. An iterative regularization technique, coupled with a saliency enhancement strategy, is also employed to improve the denoising performance. Experimental results show that the method is comparable to existing advanced denoising algorithms in terms of reducing speckle noise and preserving image details.

Aiming at the problem that the existing video traffic parameter extraction methods are overly dependent on manual annotation and a single perspective cannot effectively correct the dynamic driving deviation of vehicles on site, a multi-perspective video traffic parameter extraction method that can segment and cross lane dividing lines is proposed. The method consists of an automatic annotation point generation module and a multi-perspective correction module. The automatic annotation point generation module realizes the process of automatically generating annotation points by constructing a reference block based on equal-length lane dividing lines. The multi-perspective correction module proposes multiple mapping methods between vehicles and lane dividing lines and a correction speed measurement method based on the average speed probability density function to correct the two types of deviations generated by vehicles during dynamic driving. Experimental results on public data sets and measured data sets show that the vehicle speed extraction accuracy of the proposed method is better than other speed measurement methods, and it has a certain degree of universality.

&lt;p&gt;The penetration of renewable energy sources, electric vehicles (EVs) and load dynamics, and network complexities often lead to nuisance tripping in grid-connected microgrids. Traditional protection methods fail to discriminate fault and other dynamic volatilities in the system. The paper presents a novel two-level adaptive relay algorithm to avoid nuisance tripping in a grid-connected microgrid under varying grid dynamics. The novelty of the adaptive relay algorithm is that nuisance tripping is eliminated by precisely determining normal system-level dynamics at the first level using a phase deviation reference block. The first level determines the necessity for activating the second level, which consists of a detection scheme combining a multiclass support vector machine (SVM) and discrete wavelet transform (DWT). The hybrid DWT-SVM methodology ensures effective fault diagnosis, adapting to variations in energy sources, load fluctuations, and fault scenarios. Real-time hardware-in-the-loop (HIL) simulation validates the system’s effectiveness in dynamic microgrid environments. Extensive experiments on scenarios, including faults, fluctuations in renewable energy generation, and intermittent simulations of EV charging and capacitor switching, were conducted to test the efficacy of the adaptive relay algorithm. Finally, experiments using OPAL-RT HIL real-time simulator and the Raspberry Pi microcontroller validated the adaptive relay algorithm in a grid-connected microgrid under varying grid dynamics.&lt;/p&gt;

With LiDAR (Light Detection and Ranging) time series being used for various applications, the optimal realization of a common geodetic datum over many epochs is a highly important prerequisite with a direct impact on the accuracy and reliability of derived measures. In our work, we develop and define several approaches to the adjustment of multi-temporal LiDAR data in a given software framework. These approaches, ranging from pragmatic to more rigorous solutions, are applied to an 8-year time series with 21 individual epochs. The analysis of the respective results suggests that a sequence of bi-temporal adjustments of each individual epoch and a designated reference epoch brings the best results while being more flexible and computationally viable than the most extensive approach of using all epochs in one single multi-temporal adjustment. With a combination of sparse control patches measured in the field and one selected reference block, the negative impacts of changing surfaces on orientation quality are more effectively avoided than in any other approach. We obtain relative discrepancies in the range of 1–2 cm between epoch-wise DSMs for the complete time series and mean offsets from independent checkpoints in the range of 3–5 cm. Based on our findings, we formulate design criteria for setting up and adjusting future time series with the proposed method.

Thermoelectric generator modules (TEMs) are in common use as power sources for spacecraft. Here, we present the first investigations on a modified characterization approach for TEM with a focus on the heat flow determination under transient temperature boundary conditions with a reference block as a heat flow meter. Furthermore, we present a solution of a partial differential equation (PDE) for determining temperature fields under transient boundary conditions in single thermoelectric blocks. The PDE solution serves likewise as a reference for a numerical model using OpenModelica with a network model of the TEM measurement facility under ideal measurement conditions without parasitic heat losses. Heat flow results obtained from the numerical model are compared with the simulated transient measurement procedure, which has been derived from an analytic description of the heat conduction in the measurement configuration.

CC-SMC: Chain coding-based segmentation map lossless compression

Standard calibration blocks to assess beam paths and configure data displays using ultrasonic instruments use low carbon steel with isotropic acoustic properties. However, industry is trending towards the use of high tensile steels where the acoustic properties are anisotropic. When an ultrasonic system, calibrated on an isotropic steel reference block, is used on anisotropic steels, the beam can be bent, skewed and attenuated so that the reference setup is rendered useless. CIVA simulation software can be used to aid in understanding the effects on the data displays. As well, CIVA can help to demonstrate the degree of change that can occur when the acoustic velocities are established for the fast and slow shear modes in an anisotropic steel.

This study experimentally compares the physical and thermal properties of compressed earth blocks (CEB) stabilized with 4% of lime and reinforced with different materials. The investigated reinforcements include sisal fibers, barley straw fibers, and cork aggregates. Additionally, a reference block without any reinforcement is analyzed. The research aims to explore the impact of these reinforcements on the performance of CEB, where the physical characterization of these blocks includes assessing bulk density, water absorption, and porosity. Compressed earth block reinforced with cork (CEC) demonstrated a significant reduction in open porosity (53.85% lower), indicating enhanced insulation properties due to decreased porosity. These parameters are crucial for determining the suitability of the blocks for various environmental conditions and construction needs. Lime stabilization enhances the durability and moisture resistance of the earth blocks. Also, the addition of organic fibers (sisal and barley straw) and cork aggregates further influence these physical properties, leading to variations in weight, absorption rates, and porosity. In terms of thermal properties, the study evaluates thermal conductivity and specific heat capacity. The natural insulation properties of cork aggregates, sisal, and barley straw fibers enhance the thermal efficiency of the blocks, potentially making them more suitable for energy-efficient building designs. CEC bricks presented the lowest thermal conductivity (0.421W/mK) recording a decrease of 28.03% compared to CEB, indicating the best insulation capability among the tested materials, a vital factor for efficiency of energy. Received: December 5, 2023 Accepted: January 13, 2024