Lightweight Particle Research Articles

A lightweight particle detection algorithm based on an improved YOLOv8

Abstract A method for lightweight grain detection under transmission electron microscopy is proposed to address the issues of inadequate detection accuracy, slow speed, and high resource consumption, utilizing an improved YOLOv8. The approach involves substituting YOLOv8’s backbone structure with Mobilenetv3small, reducing model complexity while maintaining accuracy. Additionally, GsConv modules are applied to the feature enhancement network to optimize grain recognition and positioning. Experimental results show that the accuracy of the enhanced YOLOv8 reaches 97.4%, with a 66% reduction in parameters and a 70.7% decrease in computational demand, fulfilling the requirements for a lightweight experimental deployment.

A UWB-Ego-Motion Particle Filter for Indoor Pose Estimation of a Ground Robot Using a Moving Horizon Hypothesis.

Ultra-wideband (UWB) has gained increasing interest for providing real-time positioning to robots in GPS-denied environments. For a robot to act on this information, it also requires its heading. This is, however, not provided by UWB. To overcome this, either multiple tags are used to create a local reference frame connected to the robot or a single tag is combined with ego-motion estimation from odometry or Inertial Measurement Unit (IMU) measurements. Both odometry and the IMU suffer from drift, and it is common to use a magnetometer to correct the drift on the heading; however, magnetometers tend to become unreliable in typical GPS-denied environments. To overcome this, a lightweight particle filter was designed to run in real time. The particle filter corrects the ego-motion heading and location drift using the UWB measurements over a moving horizon time frame. The algorithm was evaluated offline using data sets collected from a ground robot that contains line-of-sight (LOS) and non-line-of-sight conditions. An RMSE of 13 cm and 0.12 (rad) was achieved with four anchors in the LOS condition. It is also shown that it can be used to provide the robot with real-time position and heading information for the robot to act on it in LOS conditions, and it is shown to be robust in both experimental conditions.

PIoT-blockchain-enabled security framework for strengthening IoT device identity and data access

The Internet of Things (IoT) connects billions of devices, but concerns about data security and device identification have grown. This study introduces Proof of IoT (PIoT), a novel consensus method using blockchain-based smart contracts to ensure secure data transfer and device authentication in IoT networks. PIoT employs NuCypher-based security computations for authentication and data updating, ensuring only authorized parties access blockchain-recorded information. A reward-based filtering mechanism identifies malicious nodes, bolstering consensus integrity. Simulations demonstrate PIoT's superior performance compared to conventional methods, showing a 74.7% and 96.8% improvement over LPBFT and DAC4SH Consensus, respectively. PIoT enhances blockchain security under IoT by 15% compared to DAC4SH. Beyond facilitating secure IoT device communication, this approach mitigates various IoT attacks, offering a comprehensive solution to emerging IoT security challenges. ABBREVIATION: DAC4SH, Data access control scheme for smart home; DDoS, Distributed denial of service; DoS, Denial of Service; DTLS, Datagram Transport Layer Security; IoT, Internet of Things; LPBFT, Lightweight Particle Byzantine fault tolerance; MAC, Message authentication code; MITM, Man in the Middle; PBFT, Practical Byzantine Fault Tolerance; PIoT, Proof of IoT; TLS, Transport Layer Security

Inatorial forecasting method considering macro and micro characteristics of chaotic traffic flow

Traffic flow prediction is an effective strategy to assess traffic conditions and alleviate traffic congestion. Influenced by external non-stationary factors and road network structure, traffic flow sequences have macro spatiotemporal characteristics and micro chaotic characteristics. The key to improving the model prediction accuracy is to fully extract the macro and micro characteristics of traffic flow time sequences. However, traditional prediction model by only considers time features of traffic data, ignoring spatial characteristics and nonlinear characteristics of the data itself, resulting in poor model prediction performance. In view of this, this research proposes an intelligent combination prediction model taking into account the macro and micro features of chaotic traffic data. Firstly, to address the problem of time-consuming and inefficient multivariate phase space reconstruction by iterating nodes one by one, an improved multivariate phase space reconstruction method is proposed by filtering global representative nodes to effectively realize the high-dimensional mapping of chaotic traffic flow. Secondly, to address the problem that the traditional combinatorial model is difficult to adequately learn the macro and micro characteristics of chaotic traffic data, a combination of convolutional neural network (CNN) and convolutional long short-term memory (ConvLSTM) is utilized for capturing nonlinear features of traffic flow more comprehensively. Finally, to overcome the challenge that the combined model performance degrades due to subjective empirical determined network parameters, an improved lightweight particle swarm is proposed for improving prediction accuracy by optimizing model hyperparameters. In this paper, two highway datasets collected by the Caltrans Performance Measurement System (PeMS) are taken as the research objects, and the experimental results from multiple perspectives show that the comprehensive performance of the method proposed in this research is superior to those of the prevalent methods.

Studies on sol-gel bonded inorganic based plates having expanded lightweight inclusions for improving energy efficiency

Thermal insulation materials are a great solution to minimize energy consumption for construction applications. Especially, expanded inorganic lightweights are excellent candidates in terms of their low thermal conductivity and high fire resistance properties. Sol-gel type inorganic based binders are also useful chemical substances to combine lightweight particles. In current study, inorganic-based plates were developed by using expanded glass, expanded vermiculite, and expanded perlite particles with a novel tetraethoxysilan (TEOS)/methyltrimethoxysilane (MTMS) sol-gel binder. The chemical, physical, mechanical and thermal properties of the plates were examined comparatively to reveal the effect of expanded lightweight particle types in the plates. According to the experimental results, the compressive strength of the developed plates was between 7.04 ± 0.44 MPa and 3.15 ± 0.17 MPa whilst the direct tensile strength ranged from 0.486 ± 0.04 MPa and 0.079 ± 0.04 MPa, respectively. Furthermore, the long term water absorbency values of the plates on the 28th day varied between 9.96 ± 0.04 v% and 49.8 ± 0.8 v%. On the other hand, while the thermal conductivity coefficient of the plates at 25 °C ranged from 0.125 to 0.254 W/m.K, infrared reflectance properties were determined between 83.2 ± 0.5 % and 64.1 1.8 %. Besides, all inorganic-based plates exhibited high fire resistance performance (withstand temperatures of up to ∼900 °C for 30 min). The results demonstrated that utilizing expanded inorganic lightweight particles with TEOS/MTMS sol-gel binder could be a promising combination to construct energy saving insulating plates to overcome poor fire resistance properties of conventional organic materials.

A Particle Reinforced Gradient Honeycomb Sandwich Panel for Broadband Sound Insulation

The sound insulation capacity of traditional sound insulation boards is limited by the law of mass, and any improvement in sound insulation capacity contradicts the demand for light weight. In order to overcome this shortcoming, a lightweight particle reinforced gradient honeycomb sandwich panel is proposed to achieve lightweight sound insulation. The sound insulation of the particle reinforced honeycomb sandwich panel is calculated based on the transfer matrix method. The accuracy of the theory is verified through finite element simulation, and the influence of material and structural parameters on the sound insulation performance of the sandwich panel is analyzed. The results show that the sound insulation of the honeycomb sandwich panel can be significantly improved by adding reinforcement particles to the aluminum matrix, and the sound insulation also increases as the particle mass fraction of the reinforcement increases. In addition, the valley value of the sound insulation curve moves towards the low frequency direction, which indicates that the sound insulation performance of the sandwich plate at low frequencies is effectively improved.

Using a Traveling-Wave Piezoelectric Device to Generate a Liquid Wave for Efficient Lightweight Particle Transfer

In this study, the transfer process of extremely light and small-sized particles along a defined direction without flipping them over on the transportation surface is evaluated by using a traveling wave. For this, the use of a liquid, as the contact layer injected onto the top surface of a piezoelectric traveling-wave device, is proposed to transmit the wave into the particles. As a preload is unlikely to be assigned here, the adhesion force between the lightweight particle and the liquid is expected to dominate the delivery effect. A short-beam linear motor is chosen as an example of a piezoelectric device that can generate a traveling wave in association with several selected liquids such as water, saline water, oil, and glycerol. The influence on the traveling-wave amplitude transmitted to liquids with different viscosities and heights is studied by an analytical approach and the finite-element simulation. The surface energy theory is used to determine the adhesion force between the liquid and the lightweight particle. An experiment is conducted to measure the speed of particles with variable sizes that are transported by the liquid wave. The analytical and experimental results are in good agreement, verifying the influence of the above concerned factors on the particle transfer speed.

Effects of lightweight particle content on the mechanical strength of cylindrical aggregates


 
 
 
 By using an extensive three-dimensional discrete element method, we numerically investigate the effects of lightweight particle content on the mechanical strength of the cylindrical aggregates, randomly composed of two different groups of primary particles: light (low stiffness) and heavy (high stiffness), and the stress contribution of the heavy-heavy, light-heavy, and light-light interactions on the mechanical behavior of such aggregates, subjected to the compression test by using a constant downward velocity. The interactions between primary particles are modeled by using the frictional-contact force law with a giving approximate analytical expression of capillary cohesion forces. We found that the lightweight particle content significantly affects the mechanical stress of aggregates and stress contribution obtained by different interaction types above, and the stress obtained by heavy-heavy interactions strongly dominates the mechanical strength of agglomerates. Remarkably, meanwhile, the stress obtained by the heavy-heavy contacts gradually decreases with increasing the lightweight particle content up to 20%, leading to the decrease of the mechanical strength, the stresses obtained by light-light and light-heavy contacts increase gradually. For higher lightweight particle contents, the results continuously show the same tendencies but with lower rates.
 
 
 

A review on performance of cenosphere utilization in concrete

Cenospheres are waste merchandise generated from coal combustions. It is a lightweight particle present in fly ash. Cenospheres are hollow spherical material that mainly consists of silica and alumina in large amounts filled with air or inert gases. They are lightweight and have a low density which offers them greater buoyancy. They are used in the production of Light-Weight Concrete as they offer less density and excellent thermal resistance. This paper presents a review of the performance of Cenosphere utilization in the concrete. The cenospheres blended into cementitious composite altered the mechanical and durability properties. Hence, it's critical to look into cenospheres' characteristics and their properties. Several assessments had been performed using distinct methods. Cenospheres are blended with unique substances in unique compositions and tested for their mechanical and durability properties. Cenospheres can be mixed into cementitious materials, resulting in Light-Weight Concrete.

Chiral core-shell microspheres β-CD-COF@SiO2 used for HPLC enantioseparation

Chiral covalent organic frameworks (CCOFs) have potential application in enantioseparation due to their advantages, such as large surface area, abundant chiral recognition sites and good chemical stability in organic solvents. However, the application of CCOFs in high performance liquid chromatography (HPLC) for enantioseparation has been rarely reported because of the shortcomings of CCOFs, such as light weight, irregular shape, and wide particle size distribution. In order to overcome the above shortcomings, a one-pot synthetic method was adopted to prepare a core-shell composite (β-CD-COF@SiO2) via the growth of chiral β-CD COF on the surface of amino-functionalized SiO2 microspheres. The as-prepared β-CD-COF@SiO2 microspheres were used as a stationary phase for HPLC enantioseparation. The resolution ability of the β-CD-COF@SiO2-packed column toward various chiral compounds was investigated using n-hexane/isopropanol as the mobile phase. The results show that the chiral β-CD-COF@SiO2-packed column exhibited excellent chiral recognition ability for 24 pairs of chiral compounds with good reproducibility. These successful applications indicate that the preparation of the chiral COFs@SiO2 core-shell microspheres as a novel stationary phase for enantioseparation has good application prospects in HPLC.

Low Density, High Compressive Strength: Experimental Investigation with Various Particle Sizes of Sand for Different Mix Designs of Cement Mortar Manufacturing

Concrete density was optimised by substituting part of the normal-density aggregates (fine aggregate, coarse aggregate, or both) with that of comparable quantities of low-density aggregate, which enhanced structural efficiency (strength to density ratio), improved hydration and decreased transportation costs. These days, focus is given on enhancing the characteristics of concretes in order to make them more efficient. A factor associated in compressive strength, packing particle, water absorption and density is concrete proportioning. A good proportioning mix results in greater strength for concrete at optimum density and specified age. The filler effect is regarded as a physical feature pertaining to small particles for a concrete material since it allows generating extra compressive strength by filling voids by making mortar or concrete more homogeneous. This behaviour allows conferring additional compressive strength as well as optimise or minimise the concrete’s density without having to use a pozzolanic reaction or a chemical reaction. Mainly, this objective has been implemented through using three different lightweight particle sizes of sand group a-(1.18 mm ≤ Sand size < 200 ɱm), b-(2.36 mm ≤ Sand size < 1.18 mm) and (5.0 mm ≤ Sand size < 2.36 mm). The parameters that are taken consideration during the investigation were sand particle size, water/cement ratio, cement/sand ratio. In general, the results demonstrated that there was a decrease in compressive strength when the sand’s particle sizes increased. In case the particle size group (b) and (c) used the decrease rate in compressive strength was 7.97% and 12.39% respectively in comparison with particle size group (a) where the optimum values of the water/cement and cement/sand ratio were used. On the other hand, low density was achieved at the point of the higher compressive strength, whereas 4.4% and 3.66 % increase in the density was recorded over the particle sizes of sand (b and c) respectively. Meanwhile, we put forward the relationships existing between the compressive strength as well as density of concrete mixtures with various proportions of the lightweight aggregates as given above. The conducted experimental studies showed that there were tendencies to possibly utilise various quantities of fine lightweight aggregates as well as their combinations to yield concrete mixtures based on the requirements in practical application. As per the study conclusion, the considered mixtures could be used to yield structural elements that need high compressive strength and lower density.

Lightweight Particle Filter for Robust Visual Tracking

Particle-filter-based methods have made significant contributions to achieve robust visual tracking over the past few years. Although these tracking algorithms achieve superior performance, their real-time application has typically been hindered by the high computational burden attributed to the sampling process of the particle filter. In this paper, we propose an innovative lightweight particle filter tracking (LPFT) approach that retains the robust tracking ability of the particle filter while alleviating the time-consuming sampling burden by the correlation filter method with response maps. Specifically, the proposed tracker fully utilizes the location and confidence information of these maps to predict the object, thereby training a more robust correlation filter based on more accurate predictions compared with standard correlation filters. Additionally, in contrast to most particle-filter-based trackers, the LPFT tracker capable of handling large-scale variations can be incorporated into any tracker that requires fast and accurate scale estimation. We propose the generic parallelization framework and implement another version of the LPFT tracker to validate this incorporation. Extensive evaluations on the OTB-2013 and OTB-2015 benchmarks demonstrate that the proposed tracker achieves very competitive performances with state-of-the-art trackers while operating at over 60 frames per second using hand-crafted features.

Theoretical Analysis and Experiment of Sound Absorption Characteristic of a Layer of Fine, Lightweight Particle Powder.

Theoretical Analysis and Experiment of Sound Absorption Characteristic of a Layer of Fine, Lightweight Particle Powder.

Effects of treatments on biomass bottom ash applied to the manufacture of cement mortars

The use of biomass for power generation is increasingly common. However, one of the most important problems when using biomass is the amount of waste produced in the combustion process such as ash, which must be transported to landfills for deposition.Biomass bottom ash may contain a large amount of organic matter which is the most restrictive property for reusing this by-product. The potential reuse is determined by chemical and physical properties. The presence of light particles and organic matter confer to biomass bottom ash certain physical and chemical characteristics which significantly reduce the possibility of reuse. Previous studies have demonstrated the possibility of using biomass bottom ash in cement-treated materials, but its properties imply a decrease of compressive and flexural strength.Therefore, this paper reported the study of the mechanical and durability properties of mortars containing biomass bottom ash applying different processing methods. Cement was replaced with different rates of substitution of biomass bottom ash and several samples were treated applying different techniques, such as grinding, elimination of lightweight particles and combustion.The results showed significant improvements in the mechanical and durability properties of mortars in which some treatment were applied. Lightweight particle extraction and organic matter removal by burning considerably improved the mechanical behaviour of the manufactured mortars. Therefore, mortars with crushed biomass bottom ash without floating particles and without organic matter led to a 10% of compressive strength decrease with respect to the control mortar.Thus, this study displays a possibility of waste valorisation by means of to the reuse of this type of by-product in mortars and concretes manufacture.

Lightweight approach for multi‐objective web service composition

Service composition is an efficient way to implement a service of complex business process in heterogeneous environment. Existing service selection methods mainly utilise fitness function or constraint technique to convert multiple objectives service composition problems to single objective ones. These methods need to take effect with priori knowledge of problem's solution space. Besides, in each execution only one solution can be obtained, hence, users can hardly acquire evenly distributed solutions with acceptable computation cost. The authors also propose a lightweight particle swarm optimisation service selection algorithm for multi-objective service composition problems. Simulation results illustrate that the proposed algorithm surpasses the comparative algorithm in approximation, coverage and execution time.

Fast weighted centroid algorithm for single particle localization near the information limit.

A simple weighting scheme that enhances the localization precision of center of mass calculations for radially symmetric intensity distributions is presented. The algorithm effectively removes the biasing that is common in such center of mass calculations. Localization precision compares favorably with other localization algorithms used in super-resolution microscopy and particle tracking, while significantly reducing the processing time and memory usage. We expect that the algorithm presented will be of significant utility when fast computationally lightweight particle localization or tracking is desired.

Use of MUF Resin for Improving the Wheat Protein Binder in Particle Boards Made from Agricultural Residues

This work was focused on the production and characterization of lightweight and water resistance particle boards with various lignocellulosic materials of the annual plants hemp (Cannabis sativa L.), canola (Brassica napus L.) and bagasse (Saccharum officinarum L.) in admixtures with industrial wood. Some chemical properties of these annual plants were investigated to find out their chemical characteristics in wood composites production. In all board variants 100% of the middle layers consisted of chips from one of the above annual plants. Reference boards were 100% beech wood. Laboratory manufacturing treatments included two panel density levels (500 and 600 kg/m 3 ) and three resin types (urea-formaldehyde, melamine-urea-formaldehyde and wheat protein). Water absorption and thickness swelling of the laboratory manufactured boards were improved by adding melamine to urea-formaldehyde resin and by adding water repellent chemicals. The mechanical properties of the boards produced met the requirement for the general purpose product standards (EN 312-2) at both 500- and 600- kg/m 3 densities. Decreasing the density, negatively affected the bending (modulus of rupture) and internal bond properties of canola boards. This decreasing trend was also observed for modulus of rupture values in bagasse boards of 500 kg/m 3 density. Based on the results of the chemical analysis, it might be concluded that high values of ash content and lower values of hemicellulose and lignin content caused low physical properties and/or high water absorption of canola boards. The findings indicated that hemp and bagasse are valuable renewable natural resources for particleboard production and could be utilized as a substitute for wood in board production. In comparison with the reference boards, mixed variants boards showed surprisingly good results and generally conformed to European standards (EN 312-2) values.

Effects of Adhered Mortar Content on Quality of Recycled Coarse Aggregate of Concrete

Although the adhered mortar content affects the properties of recycled aggregate concrete, there are few papers describing those effects. This paper presents the results of a series of experimental study on the effects of adhered mortar content on the quality of recycled coarse aggregate of concrete. 5 kinds recycled coarse aggregates made with heating and rubbing method, mechanical crashing method and separating lightweight particle with water stream method were tested for specific gravity, absorption and adhered mortar content. Specific gravity in oven-dried condition ranged from 2.35g/cm3 to 2.59 g/cm3, absorption ranged from 1.58% to 5.83% and adhered mortar content ranged from 8.0% to 68.4%, depending on manufacturing method of recycled aggregate. Absorption decreased linearly with the increase of specific gravity. Specific gravity decreased and absorption increased with the increase of adhered mortar content. Recycled aggregate made by heating and rubbing method showed lower adhered mortar content corresponding to lower absorption and higher specific gravity, while those made by mechanical crushing method showed higher adhered mortar content corresponding to higher absorption and lower specific gravity. In conclusion, the upper limit of adhered mortar content of recycled coarse aggregate is considered to be 15%, in order to keep up the quality of coarse aggregate and properties equal to natural coarse aggregate.

A particle bed heater for creating a clear, high-temperature, high-pressure gas flow

The design and operation of a compact, lightweight particle bed heater for rapidly loading (≤1 s) a 1000 cm3 test chamber with clear, high-temperature (100≤T≤600 °C), high-pressure (10≤P≤50 MPa) gas is described. The device facilitates the design of short duration (≤10 s) experiments where visualization of dynamic systems at such conditions are desired. The heater has enabled visualization of reactive spray phenomena in our laboratory, and its performance in this application is summarized.

Technology of thermal hypervelocity launchers

A new type of hypervelocity launcher is described, the Thermal Hypervelocity Launcher (THL). The THL uses stored thermal energy in a compact, lightweight particle bed heater to rapidly (milliseconds) heat a high pressure low molecular weight propellant (hydrogen or helium). The hot propellant then expands in a conventional barrel accelerating the projectile. The THL can achieve velocities up to -12 km/sec. The technology of the THL is described, including experiments on thermal-hydraulics of particle bed heaters. An experiment that will demonstrate THL operation with 100 gram projectiles at 3 km/sec is being attempted.