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Since Charles Goodyear discovered the method of sulfur curing Natural Rubber in 1839, many studies have been carried out to understand its mechanism. Currently, the broadly accepted mechanism includes an activated accelerator complex formed by Zinc oxide, stearic acid, accelerators and sulfur. Furthermore, it is also broadly accepted that the coupling of the sulfur to the polymer takes place in the allylic position to the double bond. Modern passenger car tire treads no longer contain Natural Rubber but instead a blend of Solution Styrene Butadiene Rubber and Butadiene Rubber, filled with a silica/silane system. Is it possible to transfer all the gained knowledge from the Natural Rubber crosslink reaction to such modern passenger car tire tread formulations, or is it required to "re-think" sulfur curing? [ABSTRACT FROM AUTHOR]

SPring‐8‐II is a major upgrade project of SPring‐8 that was inaugurated in October 1997 as a third‐generation synchrotron radiation light source. This upgrade project aims to achieve three goals simultaneously: achievement of excellent light source performance, refurbishment of aged systems, and significant reduction in power consumption for the entire facility. A small emittance of 50 pm rad will be achieved by (1) replacing the existing double‐bend lattice structure with a five‐bend achromat one, (2) lowering the stored beam energy from 8 to 6 GeV, (3) increasing the horizontal damping partition number from 1 to 1.3, and (4) enhancing horizontal radiation damping by installing damping wigglers in long straight sections. The use of short‐period in‐vacuum undulators allows ultrabrilliant X‐rays to be provided while keeping a high‐energy spectral range even at the reduced electron‐beam energy of 6 GeV. To reduce power consumption, the dedicated, aged injector system has been shut down and the high‐performance linear accelerator of SACLA, a compact X‐ray free‐electron laser (XFEL) facility, is used as the injector of the ring in a time‐shared manner. This allows the simultaneous operation of XFEL experiments at SACLA and full/top‐up injection of the electron beam into the ring. This paper overviews the concept of the SPring‐8‐II project, the system design of the light source and the details of the accelerator component design. [ABSTRACT FROM AUTHOR]

The characteristics of shotcrete can lead to significant shrinkage deformation, presenting potential threats to tunnel structure safety. To research this concern, in this study the effects of three accelerators on the volume stability of cement paste, cement mortar and concrete were investigated. The correlation equations of the shrinkage deformation of cement paste, cement mortar and concrete were established, and the drying shrinkage prediction model of cement mortar with accelerator was constructed by combining the ACI 209 model and the GL2000 model. Findings from this study show that the liquid alkali accelerator AR had the greatest autogenous shrinkage and drying shrinkage, with the highest mass loss under drying conditions. The study demonstrated that there exists a good linear relationship between the shrinkage deformation of cement paste, cement mortar and concrete with accelerator. Finally, the proposed prediction model for drying shrinkage of cement mortar exhibits strong predictive capabilities. [ABSTRACT FROM AUTHOR]

WebAssembly (WASM) has emerged as a novel standard aimed at enhancing the performance of web applications, developed to complement traditional JavaScript. By offering a platform-independent binary code format, WASM facilitates rapid and efficient execution within web browsers. This attribute is particularly advantageous for tasks demanding significant computational power. However, in resource-constrained environments such as embedded systems, the processing speed and memory requirements of WASM become prominent drawbacks. To address these challenges, this paper introduces the design and implementation of a hardware accelerator specifically for WASM. The proposed WASM accelerator achieves up to a 142-fold increase in computation speed for the selected algorithms compared to embedded systems. This advancement significantly enhances the execution efficiency and real-time processing capabilities of WASM in embedded systems. The paper analyzes the fundamentals of WebAssembly and provides a comprehensive description of the architecture of the accelerator designed to optimize WASM execution. Also, this paper includes the implementation details and the evaluation process, validating the utility and effectiveness of this methodology. This research makes a critical contribution to extending the applicability of WASM in embedded systems, offering a strategic direction for future technological advancements that ensure efficient execution of WASM in resource-limited environments. [ABSTRACT FROM AUTHOR]

Two water-soluble block copolymers composed of acrylic acid (AA), 2-acrylamido-2-methylpropane sulfonic acid (AMPS), and optionally maleic anhydride (MAH) were synthesized through ammonium persulfate-catalyzed free radical polymerization in water. The introduction of aluminum sulfate (AS) into the resulting mixtures significantly reduced the setting times of the paste and enhanced the mechanical strength of the mortar compared to both the additive-free control and experiments facilitated solely by pure AS. This improvement was primarily attributed to the inhibition of rapid Al3+ hydrolysis, which was achieved through coordination of the synthesized block copolymers, along with the formation of newly identified hydrolytic intermediates. Notably, the ternary copolymer (AA–AMPS–MAH) exhibited superior performance compared to that of the binary copolymer (AA–AMPS). In the early stages of cement setting, clusters of ettringite (AFt) were found to be immobilized over newly detected linkage phases, including unusual calcium silicate hydrate and epistilbite. In contrast to the well-documented role of polymers in retarding cement hydration, this study presents a novel approach by providing both accelerating and hardening agents for cement setting, which has significant implications for the future design of cement additives. [ABSTRACT FROM AUTHOR]

Shotcrete is one of the most important types of concrete used in engineering construction, and its properties are significantly influenced by accelerators. This study investigates the effects of aluminum sulfate series alkali-free accelerator (AKF) and alkali accelerator (ALK) on the strength, hydration process, characteristic hydration products, and microstructure properties of shotcrete. Techniques such as setting time measurement, isothermal calorimetry, simultaneous thermal analysis, scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM–EDS), and mercury intrusion porosimetry (MIP) were utilized. The results indicate that both ALK and AKF significantly accelerate and increase the early hydration heat release rate and cumulative hydration heat of Portland cement, producing the characteristic hydration products hexagonal plate AFm and rod AFt, respectively. This acceleration notably speeds up the setting process of Portland cement. ALK negatively impacts the later-stage microstructural development and pore structure filling of hardened cement paste, leading to average reductions of 15.3% and 19.9% in flexural and compressive strengths at 28 days, respectively. Specifically, compared to ALK, AKF shows a faster hydration heat release rate during the induction period and a more significant increase in cumulative hydration heat during the hydration process; the cumulative hydration heat is on average 18.2% higher than AKF. Furthermore, AKF does not hinder the subsequent C3S hydration and C-S-H gel densification process. After 28 days of curing, EDS analysis indicates an average Ca/Si ratio of 1.171 for the AKF-treated shotcrete; the average Ca/Si ratio shows minimal variation from the reference group and is classified as the same type of C-S-H gel as the reference group. Therefore, the strength of hardened cement paste with AKF continues to increase steadily in the later stages. At 28 days, the average flexural strength increased by 10.2%, while the compressive strength decreased by only 3.0%. These findings suggest that AKF enhances the microstructural development and strength of shotcrete, making it a more effective accelerator for engineering applications. [ABSTRACT FROM AUTHOR]

Background Purpose Methods Results Conclusions Accelerator‐based boron neutron capture therapy (AB‐BNCT) systems are becoming commercially available and are expected to be widely used in hospitals. To ensure the safety of BNCT, establishing a quality assurance (QA) program and properly managing the stability of the system are necessary. In particular, a high level of beam output stability is required to avoid accidents because beam output is a major factor in patient dose. However, no studies have analyzed the long‐term beam output stability of AB‐BNCT systems.This study aimed to retrospectively analyze the long‐term stability of the beam output by statistical process control (SPC) based on the QA results over 3 years.The data analyzed are the results of daily QA (DQA) and weekly QA (WQA) in an AB‐BNCT system and were taken between June 2020 and September 2023. The evaluation of the stability of the beam output was based on the reaction rate between gold and neutrons calculated using the activation foil method using a gold foil. In DQA, which can be performed in a short time, the gold foil was applied directly to the beam irradiation aperture in air. In WQA, measurements were performed at the phantom surface, 2‐cm depth, and 6‐cm depth using a dedicated water phantom. The acquired data were retrospectively analyzed by individuals and a moving range chart (I‐MR chart), exponentially weighted moving average control chart (EWMA chart), and several process capability indexes (PCIs).Over 99% of the DQA I‐MR chart results were within control limits, whereas the WQA I‐MR chart results showed that 1.8%, 4.1%, and 2.0% of the measurements exceeded the control limits at the surface, 2‐cm depth, and 6‐cm depth, respectively. The variation in the reaction rate of the gold foil before and after the replacement of the target was <0.5%. The EWMA chart results revealed no significant beam output drift for either DQA or WQA. Most measured data were normal based on the results of the Anderson–Darling test and met the requirements for PCI evaluation; most PCI values were >1.0; however, the Cpmk of DQA and the 2‐ and 6‐cm depth WQAs between August 2021 and November 2022 in treatment course 2 were 0.83, 0.77, and 0.87, respectively, which were <1.0.The long‐term stability of beam output was confirmed using SPC in an AB‐BNCT system. The results of the control chart revealed no significant variation or drift in the beam output, and the quantitative evaluation using PCI revealed high stability. A routine QA program will enable us to provide safe BNCT. [ABSTRACT FROM AUTHOR]

Three double-ring B factories—PEP-II, KEKB, and SuperKEKB—were built with asymmetric beam energies to produce high luminosity at the Υ(4S) resonance producing copious B mesons and associated particle physics data, delivered to their respective particle physics detectors, BaBar, Belle, and Belle II. In PEP-II and KEKB, the primary goal was achieved to make the first measurements of charge parity (CP) violation in decays in the B meson system. PEP-II and KEKB have finished beam operations, but particle data analysis continues. SuperKEKB is extending those measurements. The beam operation of SuperKEKB with Belle II has recently started. These three accelerators have pushed the state of the art of accelerators of two-ring colliders, including small beam emittances, small interaction point beam sizes, large stored beam currents, crab cavities, top-up injection with the detectors on, bunch-by-bunch feedbacks, crab waist operation, high beam–beam parameters, high peak luminosity, and high integrated luminosity. [ABSTRACT FROM AUTHOR]

The shielded pair resonator method is a useful tool in the measurement of accelerator components, such as the beam screens used in the Large Hadron Collider (LHC), the High-Luminosity (HL) LHC, or future accelerators. It can measure the resistive losses at several frequency points by separating the resistive losses on the sample from other sources of losses. We built a new resonator to be inserted into a superconducting dipole magnet (peak magnetic field of 9.5 T) and to measure the surface resistance of beam screens, such as LHC beam screens coated with amorphous carbon (a-C). The device can measure surface resistance at any temperature between 4.2 K and 300 K, in the frequency range of 400 MHz to 1600 MHz. We conducted the first surface resistance measurements of two a-C coated beam screens at 4.2 K and showed that the 200 nm to 400 nm titanium underlayer plus 50 nm a-C only has a limited effect on the surface resistance. This first result supports the choice of this coating as baseline for the HL-LHC triplets magnets upgrade. The resonator will have an important role in the characterization of next-generation beam screens, such as a beam screen with laser-engineered surface structure (LESS). Further measurements of the LHC beam screen in the presence of magnetic fields up to 9.5 T and throughout the full temperature range are going to be reported separately. [ABSTRACT FROM AUTHOR]

Copyright of Acta Scientiarum Naturalium Universitatis Pekinensis is the property of Editorial Office of Acta Scientiarum Naturalium Universitatis Pekinensis and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose: This article summarises the presentation given at the "Hadrontherapy: status and perspectives" event. Methods: Structure, methodology, and objectives of the Next Ion Medical Machine Study collaboration are introduced. Its four Work Packages are: small synchrotrons for particle therapy, curved superconducting magnets for synchrotrons and gantries, superconducting gantry design, and high-frequency ion linacs. Synchrotrons under study include a superconducting design for carbon ion therapy, and a normal-conducting design for ions up to helium. Superconducting magnet R&D is carried out in two European projects. Within the scope of these projects, five magnet demonstrators with different technologies are in different phases of design and production. Beam optics and mechanical design of a superconducting gantry for carbon ions is being developed. A high-frequency linac design has been completed, and tests are starting on a prototype high-frequency injector. Results: The designs of two facilities based on NIMMS technological developments are presented. A carbon ion research and therapy facility was designed for the SEEIIST project, based on a conventional synchrotron with high beam intensity. A smaller facility aimed at cancer therapy and research with light ions, in particular helium beams has also been designed. Both facilities can produce FLASH-type beams. Conclusions: The traditional design of carbon ion therapy facilities can be improved by adding new features as higher beam intensity and new beam extraction schemes. A cost-effective alternative to the traditional design is a compact facility for light ions, exploiting the potential for treatment with helium ions and allowing an experimental programme with different ion species. [ABSTRACT FROM AUTHOR]

SPring-8-II is a major upgrade project of SPring-8 that was inaugurated in October 1997 as a third-generation synchrotron radiation light source. This upgrade project aims to achieve three goals simultaneously: achievement of excellent light source performance, refurbishment of aged systems, and significant reduction in power consumption for the entire facility. A small emittance of 50 pm rad will be achieved by (1) replacing the existing double-bend lattice structure with a five-bend achromat one, (2) lowering the stored beam energy from 8 to 6 GeV, (3) increasing the horizontal damping partition number from 1 to 1.3, and (4) enhancing horizontal radiation damping by installing damping wigglers in long straight sections. The use of short-period in-vacuum undulators allows ultrabrilliant X-rays to be provided while keeping a high-energy spectral range even at the reduced electron-beam energy of 6 GeV. To reduce power consumption, the dedicated, aged injector system has been shut down and the high-performance linear accelerator of SACLA, a compact X-ray free-electron laser (XFEL) facility, is used as the injector of the ring in a time-shared manner. This allows the simultaneous operation of XFEL experiments at SACLA and full/top-up injection of the electron beam into the ring. This paper overviews the concept of the SPring-8-II project, the system design of the light source and the details of the accelerator component design.

Creep, as a long-term deformation characteristic of shotcrete, significantly influences the load-bearing performance and durability of tunnel support structures. This study conducted creep tests on shotcrete under varying stress levels. The results reveal that shotcrete exhibits linear creep response within the stress range of 30%–40%, while the critical stress range for nonlinear creep response occurs between 40% and 50%. Employing SEM-EDS and XRD analysis methods, the impact of accelerator on the microstructure evolution and creep mechanism of shotcrete is explored. The accelerator accelerates the hydration of C3S, promoting the generation of AFt and C–S–H gel, leading to rapid solidification of the matrix and enhanced early strength. With the consumption of SO42− ions, AFt gradually transforms into AFm, resulting in increased matrix porosity. This phenomenon contributes to the reduced later-stage strength and substantial creep deformation of shotcrete. Based on experimental outcomes, this study evaluates the applicability of existing creep calculation models to shotcrete.

Background: The induced activity is produced in the target, monitor chamber, flattening filter (FF), collimating jaws, etc., when a high-energy photon beam is utilized for radiation therapy. This may result in add-on exposure to radiation professionals. Objective: This study aims to measure the radiation level (RL) at the treatment plane due to induced activity in the linear accelerator head. Materials and Methods: In this study, RLs were measured close to the isocenter (I), LINAC head (H), and 0.5 m lateral to the isocenter (L) inside the radiation bunker. The RLs were measured for field sizes (FS) 5 cm × 5 cm, 10 cm × 10 cm, 20 cm × 20 cm, 30 cm × 30 cm, and 40 cm × 40 cm, using 50, 100, 200, 300, 400, 500, and 1000 monitor units (MUs) at above said locations inside the bunker using 10 mega-voltage (MV), 10 MV FF free, and 15 MV radiation beam. Results: RL increases with an increase in FS and MUs at all mentioned locations inside the bunker, except for 40 cm × 40 cm FS. The present study shows that RL increases with an increase in radiation beam energy, and there was significant RL inside the bunker at the mentioned location, even after the 1 min of high-energy radiation exposure. Conclusion: Therefore, treatment with a high-energy beam should be scheduled in the later evening of the working day and the jaw should be closed to a minimum before entering the bunker and a sufficient time gap should be followed to minimize the additional exposure due to induced activation in high-energy treatment.

In light of the potential interest of Interdigital H-mode (IH) cavities for accelerating carbon ion beams beyond 5 MeV/u, we are reviewing the key geometric elements of the regular cells and end cells to optimize performance in terms of power efficiency, achievable voltage, and dipole field correction.

This paper extends previous studies by the authors that aimed to describe the effect of apparent cross-link density (CLD) of the rubber polymer networks on the fracture mechanism caused by cut and chip (CC) wear of natural rubber (NR), demonstrating the positive effect of conventional vulcanization (CV). This work is focused on the determination of the effect of CLD while keeping constant the accelerator-to-sulfur ratio A/S = 0.2, typical for CV systems. For this ratio, different sulfur quantities were chosen, and the concentration of the accelerator N-tert-butyl-benzothiazole sulphonamide (TBBS) was calculated to achieve CLDs in a range from 35 to 524 μmol·cm–3. Standard analyses such as tensile tests, hardness, rebound resilience and DIN abrasion were performed. From these analyses, the optimum physical properties of the NR-based rubber were estimated to be in the CLD range of approximately 60 to 160 μmol·cm–3. A CC wear analysis was performed with an Instrumented cut and chip analyzer (ICCA) and it was found that the highest CC wear resistance of the NR is in the CLD range of 35 to 100 μmol·cm–3. Furthermore, the effect of straininduced crystallization (SIC) of NR on CC wear and its dependence on the CLD region was discussed. For the first time, we determine a CLD range for a CV system in which the material achieves both optimal mechanical properties and CC wear resistance. [ABSTRACT FROM AUTHOR]

Cement and concrete are the most crucial and dominating engineering materials in the construction sector. Cement serves as an excellent binder for concrete and when it is treated under unusual conditions either to satisfy accelerating or retarding requirements by the construction industries, admixtures role comes into the effect. The construction industry has been searching for retarding admixtures and the optimal dosage level, particularly for ready mix concrete applications. Generally the retarding admixtures such as organic retarders (lignosulphonates, hydroxycarboxylic acids and their salts, phosphonates, sugars) or inorganic retarders (phosphonates, borates) were generally used to reduce the speed of the reaction between cement and water by altering the growth of the hydration products and/or limiting the rate of water penetration to the cement particles. The research was still in its infancy stage in terms of determining not just the appropriate dosage amount, but also the ideal retarder materials for the aforementioned uses. In considering this industrial need, an attempt was made on utilizing the usage of sugar in the concrete to study the retarding effect without affecting the strength properties of cement. The sugars usage levels were at 5, 10, 15, and 20% of the usage of cement to investigate consistency, setting time, compressive strength and micro structure properties at the curing age of 7, 14 and 28 days on the mortar specimens. The conclusions of the study reported that setting time was extended with increase of the dosage levels of sugar. However in considering the strength property, less than 5% of sugar dosage level can be better for the application as retarding agent in the industry applications. [ABSTRACT FROM AUTHOR]

High-Efficiency Video Coding (HEVC) is a video compression standard designed to improve video compression efficiency compared to its predecessor, Advanced Video Coding (AVC). HEVC provides approximately twice the compression efficiency compared to the AVC. In the HEVC system, the most computational complexity module is the Motion Estimation (ME). ME module helps reduce redundancy by compensating for motion during video compression. However, the computational complexity makes it a bottleneck in the design of high-resolution video encoders. This paper proposes an efficient architecture for the Integer ME (IME) module of the HEVC encoder. The proposed architecture introduces an efficient memory usage scheme to support the Full Search motion search algorithm. The full pipeline architecture includes 4096 Processing Elements (PE) and an adder tree to compute the Sum of Absolute Difference (SAD) for every Prediction Unit (PU) partition. The proposed architecture was designed and implemented on Xilinx Virtex-7 XC7VX550T FPGA. Our design achieved up to 275 FPS and approximately 10 FPS at 4 K video for the Search Regions of [Formula: see text] and [Formula: see text] pixels, respectively.

Deep learning has brought great development to radar emitter identification technology. In addition, specific emitter identification (SEI), as a branch of radar emitter identification, has also benefited from it. However, the complexity of most deep learning algorithms makes it difficult to adapt to the requirements of the low power consumption and high-performance processing of SEI on embedded devices, so this article proposes solutions from the aspects of software and hardware. From the software side, we design a Transformer variant network, lightweight convolutional Transformer (LW-CT) that supports parameter sharing. Then, we cascade convolutional neural networks (CNNs) and the LW-CT to construct a one-dimensional-CNN-Transformer(1D-CNN-Transformer) lightweight neural network model that can capture the long-range dependencies of radar emitter signals and extract signal spatial domain features meanwhile. In terms of hardware, we design a low-power neural network accelerator based on an FPGA to complete the real-time recognition of radar emitter signals. The accelerator not only designs high-efficiency computing engines for the network, but also devises a reconfigurable buffer called "Ping-pong CBUF" and two-level pipeline architecture for the convolution layer for alleviating the bottleneck caused by the off-chip storage access bandwidth. Experimental results show that the algorithm can achieve a high recognition performance of SEI with a low calculation overhead. In addition, the hardware acceleration platform not only perfectly meets the requirements of the radar emitter recognition system for low power consumption and high-performance processing, but also outperforms the accelerators in other papers in terms of the energy efficiency ratio of Transformer layer processing. [ABSTRACT FROM AUTHOR]

Startup accelerators have emerged as a prominent mechanism for supporting early-stage ventures, yet questions persist regarding their effectiveness. This study addresses the gap in understanding by investigating whether accelerators promote the growth of all startups or only those already successful. Leveraging web-search traffic data as a proxy for startup growth, trend analysis is used to assess the impact of acceleration. Using a sample of 103 startups from Y Combinator from 2017 and 2018, the analysis reveals that accelerators aid startups regardless of their pre-acceleration growth status (i.e. growing, stagnating or declining). Furthermore, non-growing startups selected for acceleration exhibit better chances of achieving growth post-acceleration compared to already growing counterparts. These findings add important insights into the understanding of accelerators’ effectiveness, demonstrating that accelerators work for all selected startups, not only for those already successful. Our findings offer two important practical implications: policymakers and stakeholders should continue supporting accelerators due to their positive impact on startup growth and reducing uncertainty; startups should focus on their future potential and vision when applying for an acceleration program. Using the introduced approach, future research could compare the effectiveness of accelerators offering offline and online programs, targeting specific industry sectors, and across different periods. [ABSTRACT FROM AUTHOR]

Although self-adhesive resin cements are convenient and less technique-sensitive materials for dental clinicians, they exhibit a lower degree of conversion due to acidic components in their composition. Supplementation of the initiator, accelerator, and activator in self-adhesive resin cements has been suggested to compensate for the lower degree of conversion. This study aimed to evaluate the effects of different combinations of self-curing initiators, self-curing activators, and accelerators on the degree of conversion (DC) of self-adhesive resin cements. A dual-cured self-adhesive resin was prepared using six combinations of initiators, activators, and accelerators. The change in the DC over time was evaluated with and without light curing. The film thickness, flow properties, and cytotoxicity of each formulation were assessed. The results showed that all supplemental components had an effect on increasing the DC, but a greater increase in the DC was observed in the following order: activator, accelerator, and initiator. The cytotoxicity of the resin cements was related to the DC values, as resin cements with lower DC values exhibited higher cytotoxicity. The film thickness met the ISO standards for all groups. The results suggest that utilizing an activator is the most effective approach to enhance the DC in self-adhesive resin cement and that cytotoxicity tended to increase with lower DC values, whereas film thickness and flow properties demonstrated no correlation with DC values. [ABSTRACT FROM AUTHOR]

Background: The induced activity is produced in the target, monitor chamber, flattening filter (FF), collimating jaws, etc., when a high-energy photon beam is utilized for radiation therapy. This may result in add-on exposure to radiation professionals. Objective: This study aims to measure the radiation level (RL) at the treatment plane due to induced activity in the linear accelerator head. Materials and Methods: In this study, RLs were measured close to the isocenter (I), LINAC head (H), and 0.5 m lateral to the isocenter (L) inside the radiation bunker. The RLs were measured for field sizes (FS) 5 cm x 5 cm, 10 cm x 10 cm, 20 cm x 20 cm, 30 cm x 30 cm, and 40 cm x 40 cm, using 50, 100, 200, 300, 400, 500, and 1000 monitor units (MUs) at above said locations inside the bunker using 10 mega-voltage (MV), 10 MV FF free, and 15 MV radiation beam. Results: RL increases with an increase in FS and MUs at all mentioned locations inside the bunker, except for 40 cm x 40 cm FS. The present study shows that RL increases with an increase in radiation beam energy, and there was significant RL inside the bunker at the mentioned location, even after the 1 min of high-energy radiation exposure. Conclusion: Therefore, treatment with a high-energy beam should be scheduled in the later evening of the working day and the jaw should be closed to a minimum before entering the bunker and a sufficient time gap should be followed to minimize the additional exposure due to induced activation in high-energy treatment. [ABSTRACT FROM AUTHOR]

This study proposes a new method for diagnosing Parkinson's disease using audio signals and FPGA-based convolutional neural networks. The proposed method involves training a convolutional neural network and using deep learning techniques to increase its accuracy. The method is implemented on an FPGA chip to reduce latency and storage space. This work achieves higher accuracy and lower delay than other methods. The study also explores the potential of using the dropout approach during network training to improve the learning of convolutional neural networks. The findings of this study suggest that the proposed method can be a useful tool for diagnosing Parkinson's disease with audio data. Contributions and novelties of this work include the use of FPGA-based convolutional neural networks for Parkinson's disease diagnosis, the implementation of the method on an FPGA chip, and the exploration of the dropout approach for improving the accuracy of convolutional neural networks. The proposed method achieves higher accuracy and lower delay than other methods, making it a useful tool for diagnosing Parkinson's disease with audio data. The use of a new accelerator with a dropout technique and lowering the learning rate to increase detection accuracy is also a novel contribution to the field of machine learning. In addition, the proposed method eliminates the need to store convolution mapping, reducing the chip volume and computational volume, and the integrated chip is much smaller in volume and uses less power than prior generations. The method is developed and trained on audio data to detect Parkinson's disease and then implemented on an FPGA using a high-end hardware accelerator architecture. By reducing the bit width, this method decreases the space used by the logical cells and minimizes latency via the proposed computational model and parallel computations. [ABSTRACT FROM AUTHOR]

Extensive nuclear data studies have been carried out over the last 30 years in the context of accelerator-based production of radionuclides, especially at energies below 30 MeV, and the achieved database is fairly good. Yet there are some deficiencies or new needs of data. Those needs are generally associated with new emerging clinical applications of radionuclides, e.g. theranostic approach, bimodal imaging, radioimmuno-therapy, etc. This article gives an overview of on-going nuclear data research utilizing charged-particle accelerators in four directions, namely low-energy region, intermediate energy range, use of the α-particle beam, and utilization of fast neutrons generated at accelerators. Wherever possible, a comparison of experimental data with theoretical estimates is presented and evaluated (standardised) data, if available, are also briefly discussed. [ABSTRACT FROM AUTHOR]

Graft copolymerization continuestoplay important role in the modification of wide range of polymer materials for industrial application. The objective of this study was to investigate the effect of variedinitiation time of benzoyl peroxide-N,N-dimethyl-para-toludinecouple system by free radical solution polymerization on the mechanical, swelling and morphological properties of polyurethane-graftpolymethylmethacrylate copolymer using appropriate standard methods. The tensile and flexural properties for HDPU-1.02-g-PMMA and TDPU-1.02-g-PMMA increased within (20-30 min.) initiation time and decreased thereafter, these parameters for MDPU-1.02-g-PMMA, increased over the whole range of initiation time (20-40 min.). The copolymers showed maximum and minimum swelling in chloroform and propanol respectively, with exception of propanol, MDPU-1.02-g-PMMA copolymer presents the highest swelling in other solvents. HDPU-1.02-g-PMMA and TDPU-1.02-g-PMMA copolymers prepared at40 min. initiation time showed macrophase separation. In contrast, MDPU-1.02-g-PMMAprepared at identical condition, indicates an encapsulated polymethylmethacrylate chain within the MDPU-polymer matrix. The results showed that Ximeniaamericana seed oil was an effective precursor for polyurethane-graft-polymethylmethacrylate copolymers with physico-mechanical properties characterized by structural orientation of the base polyurethane matrix and polymerization initiation time. [ABSTRACT FROM AUTHOR]

EPDM (ethylene propylene diene monomer) is a type of synthetic rubber. The products of rubber have great importance in every part of life. EPDM rubber has high tensile strength, high tension, toughness, and is weather resistant. Therefore, EPDM (ethylene-propylene-diene rubber) is widely used in many fields. The aim of this study is to examine the effect of accelerator type on mechanical properties and vulcanization characteristics of EPDM rubber. We used the accelerators; thiazole, sulfonamides, dithiocarbamate, thiuram, and guanidine groups. The results show that the fastest cure time and the best tensile strength are achieved with dithiocarbamates for EPDM rubber. [ABSTRACT FROM AUTHOR]

Copyright of Religación: Revista de Ciencias Sociales y Humanidades is the property of Religacion: Revista de Ciencias Sociales y Humanidades and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of New Building Materials / Xinxing Jianzhu Cailiao is the property of New Building Materials Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The question of neutrino beam formation with parent particles deflected to one side is discussed. The optical scheme of the channel is proposed to use a dispersionless two-magnet system with a field lens to select the required momentum interval of parent pi mesons. The dipole magnets deflect the beam to one side, so the decay part of the channel is rotated with respect to the direction of pointing of the primary proton beam at the target. The protons that do not interact in the target are dumped onto the absorber, the longitudinal coordinate of which corresponds to the beginning of the decay tube. The main parameters of the pi meson beam at the beginning of the decay section, as well as the neutrino characteristics at the far and near detectors located at a distance of 2595 km and 100 m from the end of the decay section of the channel, respectively, are discussed. [ABSTRACT FROM AUTHOR]

With the recent advancements in high-performance computing, convolutional neural networks (CNNs) have achieved remarkable success in various vision tasks. However, along with improvements in model accuracy, the size and computational complexity of the models have significantly increased with the increasing number of parameters. Although graphics processing unit (GPU) platforms equipped with high-performance memory and specialized in parallel processing are commonly used for CNN processing, the significant power consumption presents challenges in their utilization on edge devices. To address these issues, research is underway to design CNN models using field-programmable gate arrays (FPGAs) as accelerators. FPGAs provide a high level of flexibility, allowing efficient optimization of convolution operations, which account for a significant portion of the CNN computations. Additionally, FPGAs are known for their low power consumption compared to GPUs, making them a promising energy-efficient platform. In this paper, we review and summarize various approaches and techniques related to the design of FPGA-based CNN accelerators. Specifically, to comprehensively study CNN accelerators, we investigate the advantages and disadvantages of various methods for optimizing CNN accelerators and previously designed efficient accelerator architectures. We expect this paper to serve as an important guideline for future hardware research in artificial intelligence. [ABSTRACT FROM AUTHOR]

Owing to their large accelerating gradients, plasma-based accelerators have attracted considerable interest as potential drivers for future, compact electron-positron colliders. Despite great progress achieved in plasma-based electron acceleration, positron acceleration still remains a challenging task, with an efficient positron source being the prerequisite for such acceleration. Here a concept for a compact, two-stage plasma-based positron source is discussed. In the first stage the positrons are created by a multi GeV electron beam produced by a laser-plasma accelerator interacting with a solid density foil. In the second stage the positrons are captured and accelerated in a plasma wave driven by either an electron beam or a laser pulse. Three potential configurations of such a source are considered: (i) a single electron beam is used for both the creation of positrons in the foil and for driving the wakefield in the second stage; (ii) a train of two electron beams is used: the positrons produced by the trailing beam in the foil are captured and accelerated in the second stage by the plasma wave generated by the leading beam; and (iii) a single electron beam is used to produce positrons in the foil and an independent laser pulse is coupled to the second stage to drive the plasma wave. These three configurations show different degrees of effectiveness with positron capture efficiency, varying from less than a percent to almost half of all produced positrons.

Graph convolution networks (GCN) have demonstrated success in learning graph structures; however, they are limited in inductive tasks. Graph attention networks (GAT) were proposed to address the limitations of GCN and have shown high performance in graph-based tasks. Despite this success, GAT faces challenges in hardware acceleration, including: 1) The GAT algorithm has difficulty adapting to hardware; 2) challenges in efficiently implementing Sparse matrix multiplication (SPMM); and 3) complex addressing and pipeline stall issues due to irregular memory accesses. To this end, this paper proposed SH-GAT, an FPGA-based GAT accelerator that achieves more efficient GAT inference. The proposed approach employed several optimizations to enhance GAT performance. First, this work optimized the GAT algorithm using split weights and softmax approximation to make it more hardware-friendly. Second, a load-balanced SPMM kernel was designed to fully leverage potential parallelism and improve data throughput. Lastly, data preprocessing was performed by pre-fetching the source node and its neighbor nodes, effectively addressing pipeline stall and complexly addressing issues arising from irregular memory access. SH-GAT was evaluated on the Xilinx FPGA Alveo U280 accelerator card with three popular datasets. Compared to existing CPU, GPU, and state-of-the-art (SOTA) FPGA-based accelerators, SH-GAT can achieve speedup by up to 3283$ \times $, 13$ \times $, and 2.3$ \times $.

High-performance sparse matrix multipliers are essential for deep learning applications, and as big data analytics continues to evolve, specialized accelerators are also needed to efficiently handle sparse matrix operations. This paper proposes a modified, configurable, outer product based architecture for sparse matrix multiplication, and explores design space of the proposed architecture. The performance of various architecture configurations has been examined for input samples with similar characteristics. The proposed architecture has been implemented on Xilinx Kintex-7 FPGA using 32-bit single precision floating-point arithmetic and also in 8-bit, 16-bit and 32-bit fixed-point arithmetic formats. The effect of quantization in the proposed architecture has been analyzed extensively and the results have been reported. The performance of the proposed architecture has been compared with state-of-the-art implementations, and an improvement of 9.21% has been observed in the performance.