Material Savings Research Articles

Recovery of Silicon Kerf Through Oxidative Cleaning and Drying Process

High quantity of slurries, kerf, are generated during ingot wafering and represent up to 40% of the silicon in weight. The highly pure silicon contained in kerf is contaminated with organics, metal impurities, water and an oxide layer. The recovery of the silicon could be an efficient way to reduce costs in the production of solar panels through material and energy savings. At high temperatures, organic contamination causes the formation of silicon carbide species that are difficult to segregate during kerf remelting into a pure silicon ingot. Also, during the fusion of silicon, temperatures up to 1500°C are reached and the mixture of silicon and water forms oxides and gases that reduce production yields and affect melting conditions. For these reason, purification and drying steps are required to ensure proper silicon raw material for remelting into ingots. So far, approaches using strong acidic or organic solvent are used to reduce contamination by organic compounds. In this study, more environmentally friendly processes were applied on authentic kerf waste to purify and dry silicon, to make it suitable as raw material for silicon ingot preparation. The amount of water and organic compounds were monitored along the process steps. Using aqueous oxidative processes in combination with filtration, kerf was cleaned and a total carbon reduction of at least 30% was observed. The control of humidity enables the convenient conditioning of purified kerf and effective drying reduced the moisture content to less than 5% wt.

Self-reported determinants for subjective financial distress: a qualitative interview study with German cancer patients

ObjectivesPatient-reported financial effects of a tumour disease in a universal healthcare setting are a multidimensional phenomenon. Actual and anticipated objective financial burden caused by direct medical and non-medical costs as...

Numerical analysis of the stresses and behavior of composite castellated beams with hexagonal holes

This study analyzes the structural behavior of Composite Castellated Beams (CCBs) with circular holes through numerical modeling. Using the Finite Element Method (FEM) in ABAQUS software, different scenarios were simulated to investigate the stress distribution around the holes in I-steel profiles and reinforced concrete slabs. The analysis revealed that, although castellated beams present higher stiffness and load-bearing capacity compared to solid profiles, the holes create complex stress states that require attention in structural design. The results showed a direct relationship between the type and arrangement of the holes with variations in Von Mises, longitudinal, and shear stresses. The study highlights the optimization potential of castellated beams, providing greater height and stiffness without increasing the weight-to-length ratio, with important implications for material savings and structural efficiency. However, additional studies are needed to better understand the long-term effects and validate the results through practical experiments.

Enhancing aerodynamic efficiency: shape modification of airfoils

Small wind turbines (SWTs) are essential for harnessing renewable energy, particularly in developing regions where energy demands are significant. They provide a sustainable solution to meet the critical energy needs of these areas. However, the low Reynolds number (Re) airflow characteristics can pose challenges, making optimising airfoil shapes essential for enhancing aerodynamic performance and energy capture. This study offers a thorough analysis of six different airfoil profiles within a Re range of 50k to 500k. Modifications to the thickness-to-camber ratio (t/c) were strategically targeted to improve aerodynamic efficiency and structural viability. Using QBLADE software, we evaluated these design alterations to optimise the lift coefficient ( C L ), drag coefficient ( C D ), stall angle of attack ( α stall ) and lift-to-drag coefficient ratio (L/D). The analysis revealed significant improvements in the maximum power coefficient ( C p . max ), with the modified BW-3 airfoil achieving a C p . max of 0.441 at a Re of 500k – a remarkable 40.5% increase over baseline values. This consistent enhancement across various Re emphasises the essential impact of aerodynamic design in enhancing energy capture and reinforcing the feasibility of SWT applications across diverse operating conditions, along with material savings that lead to lighter wind turbine (WT) blades.

Ultrasonic Molding of Poly(3-hydroxybutyrate) and Its Clay Nanocomposites: Efficient Microspecimens Production with Minimal Material Loss and Degradation

Ultrasound micromolding (USM) is an emerging processing technology that offers advantages with regard to spatial resolution, material savings, minimum time residence, minimum exposure to high temperatures, and low cost. Recent advances have been focused on nodal point technology, which improves the homogeneity of the molded samples and the repeatability of the properties of processed specimens. The present work demonstrates the suitability of a modified USM technology to process the biodegradable poly(3-hydroxybutyrate) (P3HB), which is a polymer that has well-reported difficulties when processed by conventional methods. Specifically, conventional injection, microinjection, and USM technologies with and without nodal point configurations have been compared. Degradation studies and the evaluation of thermal and mechanical properties confirmed the successful preparation of P3HB microspecimens, maintaining their functional integrity with minimal molecular weight loss. Exfoliated clay structures were observed for P3HB nanocomposites incorporating the C20 and C166 clays and processed by USM. The results highlight the advantages of the modified USM technology, as conventional microinjection failed to produce nanocomposites of P3HB/C116 due to the enhanced degradation caused by C116.

A Comparative Assessment of Hole Integrity with Twist Drill Geometry in Drilling AFRP/AL7075-T6 Stack Material

Drilling Aramid Fiber Reinforced Plastic (AFRP) with aluminium (AL7075-T6) is challenging. It is crucial to maintain the dimensional accuracy and minimize burr formation. In this study, two carbide drill bit were tested across 13 runs with varying combinations of feed rates (0.05, 0.08, 0.10 mm/rev) and spindle speeds (2000, 4000, 6000 rev/min), using a central composite design (CCD) methodology within the Design of Experiment (DOE) framework. The drill geometries included angles such as the helix angle, primary clearance angle, chisel edge angle, and point angle. For the tapered web drill bit, angles were set at 10º, 6º, 45º, and 130º, while for the burnishing drill bit, they were 20º, 8º, 30º, and 135º, respectively. The primary focus of the experiment was to assess hole quality, specifically evaluating hole diameter error and burr height formation. Among the 13 runs conducted, the tapered web drill bit exhibited superior performance in terms of hole diameter error, showing a deviation of-0.5 µm in Run 8, compared to a deviation of 1.2 µm for the burnishing drill bit in Run 12. Additionally, the tapered web drill bit demonstrated a lower burr height of 63.97 µm in Run 12, while the burnishing drill bit resulted in a burr height of 95.44 µm in Run 4. These findings enhance aircraft production by promoting better hole quality with optimal drill bits, leading to material savings, lower rejection rates and cost reduction, thus boosting reliability and productivity.

ANALYSIS OF STRENGTH AND STIFFNESS OF PERMANENT FORMWORK BLOCKS WITH A WIDTH OF 300 TO 400 MM FOR LOW-RISE CONSTRUCTION

The article investigates the structural performance of concrete blocks used as permanent formwork in low-rise construction, with widths ranging from 300 to 400 mm. These blocks serve as both formwork and part of the structural system, providing a durable solution for wall construction. In Ukraine, the adoption of such blocks is limited due to underdeveloped reinforcement methodologies, which complicates their application in construction projects. The authors examine the strength and stiffness of a standard block with dimensions of 500×400×200 mm, using software-based modeling in TechEditor to streamline the calculations. This research produces graphical data on load-bearing capacity and bending stiffness, which designers can use to configure reinforced concrete walls with these blocks. The study also offers practical reinforcement guidance, filling gaps in current standards and assisting engineers in implementing these blocks effectively. Permanent formwork blocks, common internationally, typically contain voids and channels that facilitate rebar installation, creating a monolithic structure after the concrete sets. However, due to inconsistencies in reinforcement advice from manufacturers, Ukrainian engineers often resort to custom approaches or traditional monolithic construction. This study, therefore, aims to address these challenges by providing structured reinforcement recommendations. The research includes load-bearing and stiffness calculations for walls with variable depth (300-400 mm), accounting for different rebar diameters to simulate the range of possible configurations. Findings demonstrate that using blocks with rebar yields significant material savings (approximately 33% less concrete) compared to solid walls, without proportionate strength loss, making them a cost-effective choice for low-rise construction. In conclusion, the article offers engineers and manufacturers valuable insights into the practical use of permanent formwork blocks, presenting a foundation for further research into optimization and broader applications. Keywords: reinforced concrete, block, formwork, reinforcement, analysis.

Analysis of optimization algorithm models for the design of prestressed steel beams

Prestressing in steel beams offers significant benefits in terms of structural efficiency and material savings. The aim of this study is to present a comparative analysis of the design results of prestressed steel beams obtained through three optimization algorithms: Genetic Algorithm (GA), Particle Swarm Optimization (PSO), and its variant, including a craziness operator for performance enhancement (CRPSO). These algorithms were used to minimize CO2 emissions and cost in the structural design process, while adhering to the constraints imposed by ABNT NBR 8800:2008. The implementation was carried out using MATLAB (2016). The validation of the methodology was conducted using examples from the literature, comparing the CO2 emissions and cost values obtained from experimental work and those derived from GA, PSO, and CRPSO. The results indicate that, although the Genetic Algorithm is widely used in optimization, more optimized results are achieved using PSO. Furthermore, the improvement obtained by CRPSO showed no significant deviation from those obtained by PSO, nor did it affect the convergence speeds of the results. It was also observed that all three implemented models yielded more optimized values of emissions and costs compared to those reported in the literature.

The Impact of Basalt Mesh on the Strength of Plywood

Abstract The favorable characteristics of veneer boards—plywood—enable their wide application. There is also the possibility of enhancing plywood, such as by coating it with various films, applying coatings, reinforcing it with fibers from different materials, and using improved adhesive formulas. Basalt fibers, as a natural and environmentally friendly material, are used in various forms with quite good characteristics. Results from various tests conducted in recent years indicate an improvement in the mechanical properties of composite boards, including plywood reinforced with fibers like basalt fibers. These tests were focused on determining the position and contribution of basalt fibers in the board’s structure, as well as the application of certain environmentally friendly adhesives. For this study, samples of composite material based on wood, specifically plywood reinforced with a basalt mesh, were prepared. The basalt mesh was placed within the plywood structure in various combinations of position and amount. Subsequently, a three-point bending strength test was conducted to determine the impact of the basalt mesh on the strength of the plywood. The increase in strength opens up possibilities for expanded use, material savings, and a reduction in the overall weight of the structure, which is crucial in certain applications of such boards.

AGRO-robotics: Problems and Prospects

The article discusses innovative areas of development of forestry and agricultural machinery with intelligent control systems. Kinematics is considered using the example of a harvester with a multi-link manipulator and walking chassis. Systems of equations are presented that characterize the spatial position of the working and chassis equipment with a large number of degrees of freedom. For this purpose, many companies have set themselves the task of creating multifunctional robots that operate autonomously and are controlled remotely using cloud technologies with special software. Intelligent control systems currently being developed can significantly expand the technological capabilities of machines that were unavailable in the not so distant past. The use of robots allows the introduction of new highly efficient technologies in which a person will be relieved of heavy physical labor, work in hazardous conditions, aggressive environments, etc. As a result of using robots, significant savings in material and labor resources, increased labor productivity and reduced production costs can be achieved. Currently, the use of walking vehicles for cargo transportation, clearing rubble, conducting emergency rescue operations in undeveloped areas in off-road conditions, as well as military use is considered promising. An assessment of existing problems and development prospects is given.

Attack of discarded soda-lime glass with sodium aluminate for the manufacturing of sustainable geopolymer components

Discarded soda-lime glass (SLG) may contain small amounts of ceramic, metallic, and polymeric contaminants, therefore recycling of this material is far from ideal. The quality of newly made glass products made by remelting of cullet, as a result, declines. Consolidation at low temperatures to form materials similar to geopolymers could enable the complete re-use of contaminated cullet. SLG powders, either as received or after pre-washing in an acid solution, were added to a sodium aluminate solution and mechanically stirred at a low speed for three hours at room temperature. The formation of microporous semi-crystalline monoliths involved suspensions casting into plastic molds, followed by an overnight cure at 75 °C. The monoliths prepared from both untreated SLG particles and pre-washed SLG particles contained crystalline phases of zeolite LTA and hydrosodalite. The mechanical characteristics showed good agreement with the properties of cementitious materials, with compressive strength ranging from 22 to 29 MPa and flexural strength ranging from 13.2 to 19.9 MPa. Furthermore, the technique effectively produced Venetian terrazzo-like samples by adding coarse glass particles as fillers with particle sizes of up to 3 mm, which could lead to significant material and energy savings in their fabrication. The suggested method could be expanded to include other challenging-to-reuse glass formulations, providing attractive and versatile recycled materials.

Mechanical properties variation of samples fabricated by fused deposition additive manufacturing as a function of filler percentage and structure for different plastics

One of the key factors in manufacturing products by fused deposition molding (FDM) or layer-by-layer printing technology is the material intensity of the product. The task of reducing the amount of material required to manufacture a product without significant loss of mechanical properties is one of the most practically important technological tasks. Material saving in FDM printing of products allows to reduce financial costs and increase the speed of manufacturing of the final product without reducing (or not significantly reducing) the quality properties of the product. In our work it is demonstrated that using Combs filling type and materials of poly lactic acid (PLA) and polyethylene terephthalate glycol (PETG) it is possible to achieve material savings of up to 23% at 50% filling for PLA and 17% at 75% filling for PETG without significant reduction of product strength in comparison with other filling types. Exceptions are PLA samples with 100% fill and Lateral fill. Application of Kruskal-Wallis criterion and Dunn’s criterion with Bonferroni multiple comparison correction showed that there were no statistically significant differences within the strength limits of samples made by FDM printing technology from PLA and PETG plastics (p-value = 0.0514), as well as samples with Triangle and Grid filling type (p-value = 1). Based on this result, three groups of samples statistically significantly differing in ultimate strength were identified by methods of hierarchical cluster analysis; in each group (except for group 1, which included samples made of PLA plastic with Lateral filling type and 100% filling), correlation analysis was performed (Spearman correlation was used). The results of the correlation analysis showed a stable average correlation between the percentage of filling, modulus along the secant 0.05–0.2% strain, ultimate strength and strain corresponding to the yield stress. Analysis of the correlation graph showed that the main parameter correlating with all mechanical properties of the specimen is the 0.05–0.2% strain modulus. Based on this conclusion, robust regression equations predicting the 0.05–0.2% strain modulus as a function of the percentage of specimen filling were constructed for the two selected groups. Analysis of the equations showed that in the third group of specimens, the average modulus of 0.05–0.2% strain is more than twice the modulus of 0.05–0.2% strain in the second group. The detected statistical regularities can be explained by the mechanism of strain hardening, the actual value of which depends on the structure of the macrodefect (type of filling), properties and volume of the material (percentage of filling) used in the fabrication of samples using FDM printing technology.

Engineering the microstructure: unveiling the synergistic effects of GnP and blowing agents on PA6 composite foams

With the rapid evolution of modern society, issues such as the excessive consumption of resources and environmental pollution are significantly constraining the progress of the manufacturing industry. In response to these challenges, concepts like energy conservation, emission reduction, and sustainable development have driven the development of polymer foam materials. This study focuses on the development of PA6/GnP polymer composite foams aimed at achieving material and energy savings while enhancing mechanical properties. In the first phase of the research, GnP was added to the PA6 matrix material at weight percentages of 1 %, 2 %, and 3 %, and the mixture was melt-compounded using a twin-screw extruder. The polymer composites were subsequently molded using an injection molding machine, and foams containing 3 wt% GnP were produced to investigate the effect of the maximum GnP content on the properties of the foams. In the second phase of the study, the blowing agent content in the PA6/GnP polymer composites was varied (3 %, 6 %, and 9 %) to produce foams using an injection molding machine. To assess the effect of GnP on foam formation, foams were also produced from neat PA6 using the same amounts of blowing agents. The addition of GnP generally reduced pore sizes, and by increasing the foaming agent amount, the negative effects of GnP’s high surface area were balanced. As a result, a more successful pore structure was achieved. In PA6 foams, the expansion ratio increased from 1.06 to 1.13 and 1.26 with rising CBA content, while in PA6/GnP composite foams, the ratios were 1.01 and 1.02.

Mechanical Analysis and Optimization of Concrete Structures Based on Advanced Finite Element Method

This article explores the mechanical analysis and optimization problems of concrete structures based on the Advanced Finite Element Method. By integrating advanced numerical techniques with practical engineering cases, this study aims to improve the safety and economy of concrete structure design. Firstly, the paper outlines the limitations of traditional finite element methods in concrete structure analysis, such as insufficient computational accuracy and low computational efficiency. Subsequently, by introducing AFEM, we significantly improved the accuracy and efficiency of the analysis. For example, when simulating a complex bridge structure, AFEM not only reduces the calculation time by about 25%, but also improves the accuracy of stress distribution prediction by more than 10%. In the optimization stage, we utilized the analysis results of AFEM and optimized the material consumption, cross-sectional dimensions, and reinforcement parameters of concrete structures through multi-objective optimization algorithms. A comprehensive data analysis underscores that the optimized concrete structure triumphantly meets all safety performance criteria while achieving a remarkable 12% reduction in material usage. This substantial material savings translates into a substantial 8% decrease in overall construction costs, significantly bolstering the project’s economic feasibility. Moreover, these cost savings not only amplify the project’s profitability but also play a pivotal role in enhancing the structure’s longevity and durability, thereby contributing to its sustainable performance over its entire service life. Furthermore, we delved into the capability of AFEM in simulating intricate phenomena such as the nonlinear behavior of concrete materials, crack propagation patterns, and the intricate interactions between steel reinforcements and concrete. These complex mechanical behaviors are crucial for the safety and stability of structures, and AFEM provides more comprehensive and accurate references for structural design by accurately simulating these behaviors. This article conducts in-depth research on the mechanical analysis and optimization of concrete structures based on AFEM, and demonstrates the significant advantages of AFEM in improving structural safety and economy through specific data. These research results not only provide new theoretical support and practical tools for concrete structure design, but also provide valuable references for future research and application in related fields.

Theoretical analysis of the forming process of closed die forging with flash and optimization design method of flash gutter

The subject of this article is the forming process of closed die forging with flashes and the optimal design of the flash gutter dimensions. The goal is to conduct an in-depth theoretical analysis of the forming process of closed die forging with flash and to research the optimal design of the flash gutter dimension, aiming to improve the scientificity and efficiency of the forging process, guide the optimization of process parameters in actual production, extend the service life of dies, reduce material waste, and enhance product quality and production efficiency. The tasks were to establish an accurate mathematical model for closed die forging with flash to analyze metal plastic deformation and stress distribution, to conduct in-depth research on key factors such as stress distribution, position of the neutral plane, and flash gutter design during the forming process, and to validate the mathematical model through finite element simulation using DEFORM-2D software. The methods used include theoretical analysis, mathematical modeling, and finite element simulation validation. The theoretical analysis provides a foundation for understanding the forming process and stress distribution, whereas the mathematical model allows for quantitative analysis. Validation of the finite element simulation provides a means to test and refine the theoretical analysis and mathematical model. The following results were obtained: the existing mathematical model underestimates the height of the main deformation zone, which results in an unreasonable flash gutter design. After verification and correction, the error in the optimized mathematical model did not exceed 10 %, and the flash amount was significantly reduced. Additionally, a stress analysis of difficult-to-fill cavity positions revealed that the entrance radius of the cavity significantly affects the final filling. Conclusions. The scientific novelty of the results obtained is as follows: A mathematical model of closed die forging with flash was established to analyze the metal plastic deformation and stress distribution, providing theoretical support for die design optimization, forging quality improvement, cost reduction, and productivity improvement. Using the Deform-2D finite element simulation, the optimal design criterion for the flash was refined, resulting in a substantial reduction in the flash amount and material savings.

Prediction of Screen‐Printed Electrodes with Fine‐Line and Arbitrary Structures

Currently, the photovoltaic manufacturing industry is confronted with an upcoming material shortage, primarily driven by the continued dependence on silver for front‐side metallization in TOPCon, SHJ, and PERC solar cells. This study employs a mathematical model originally introduced by Ney et al. in 2019 to predict the outcome of printed contact structures based on mesh characteristics. For validation, printing experiments are conducted with variations in printing speed, screen angle, and calendaring strength. It is generally observed that predictions for screens with a 20° mesh angle are less accurate than for other angles. In addition, it is noted that the prediction became more accurate with increasing channel width. Although, for some cases, a prediction accuracy between 77 and 87% is achieved, it is important to acknowledge that the results obtained from the simulation deviate from the real‐world observations to some extent. Additionally, a clear correlation between mesh thickness and printed volume is observed, enabling the prediction of silver usage and potential material savings.

Experimental study of shielding gas concentration on mechanical properties of stainless steel alloy parts using wire and arc additive manufacturing

Wire Arc Additive Manufacturing (WAAM) is an emerging three-dimensional fabrication technology that enables higher deposition rate, material savings, and near net-shape. In this study, various shielding gas concentration (SGC) of argon (Ar) and carbon-di-oxide (CO2) was employed to fabricate 316L using Cold Metal Transfer (CMT) WAAM process. Microstructure characteristics and mechanical properties of thick-walled parts were studied. Microstructure studies show a combination of columnar and equiaxed grains in various regions. Microhardness results exhibit the uneven distribution of hardness value from bottom to top region along the building direction and the values are ranging between185 and 240 HV. Tensile studies indicates the both horizontal and vertical direction samples secures the higher ultimate tensile strength (UTS), yield strength (YS) and elongation (EL) values and confirmed the isotropic properties. Fractography studies prove ductile fracture with the evidence of dimples and enough plastic deformation. From the experimental results, the SGC-2 possesses finer solidification structure and higher mechanical properties than the other samples. The as-fabricated WAAM parts possess higher mechanical properties than the 316L parts fabricated via casting and wrought parts.

Evaluating the Environmental Impact of Reusing Baghouse Dust in Asphalt Concrete: A Sustainable Approach

The purpose of this study is to assess the environmental impact of reusing baghouse dust in asphalt concrete production. Baghouse dust, a byproduct of asphalt creation, presents natural removal challenges; nonetheless, its true capacity reuse in asphalt concrete could give an economical solution. This study aims to survey and align the environmental and ecological implications of utilizing varying extents of baghouse dust in asphalt mix combinations. This research review starts by describing the physical and chemical properties of baghouse dust. In this way, substantial samples were ready and prepared with various percentage rates of baghouse residue to examine the effect on the mechanical properties of the mix. The discoveries demonstrate that consolidating baghouse dust into asphalt cement mostly decreases peak stress and strength qualities characteristics. As far as the environmental and ecological effect, the investigation analysis shows that utilizing baghouse residue can decrease in general energy utilization and discharge emissions. The energy utilization rate diminished from 500 MJ/ton for ordinary conventional asphalt to 400 MJ/ton for asphalt with 20% baghouse residue, and CO2 emanations decreased from 120 kg/ton to 80 kg/ton for a similar correlation. Also, the squander and waste decrease was huge, with 200 tons/year saved at 10% baghouse dust and 400 tons/year at 20%. Asset resources proficiency likewise improved, with raw unrefined material savings investment funds of 150 tons/year at 10% baghouse dust and 300 tons/year at 20%. Notwithstanding this decrease, the mechanical properties stay within ranges for specific applications, proposing that baghouse dust residue can be effectively and successfully utilized in non-basic underlying structural layers of asphalts.

Digitalisation and sustainability measures at the firm level

The paper analyses the “twin transition” of digitalisation and sustainability at the firm level. Operational definitions of digitalisation and sustainability allowing the development of fitting empirical indicators are discussed. The possible technical and social transmission channels of the effects of digitalisation on a sustainable firm development are analysed. Less energy consumption induced by intelligent sensoring systems, the reduction of meetings in presence by video conferences or the promotion of home office work leading to less travel activities may lead to a more sustainable production. Digitalisation might also act as pre-condition of eco-process innovations (e. g. the introduction of intelligent control systems leading to material and energy savings). The empirical analysis is based on firm data of the recent Eurobarometer 486/2020 of the European Commission. The econometric results show that “digitally active” firms seem to be more sustainable for all available indicators, but the marginal effects considerably differ between measures such as artificial intelligence, machine learning, or the use of smart devices and intelligent sensors for the various sustainability-related activities of the firms.

Design Optimisation of a Flat-Panel, Limited-Angle TOF-PET Scanner: A Simulation Study.

In time-of-flight positron emission tomography (TOF-PET), a coincidence time resolution (CTR) below 100 ps reduces the angular coverage requirements and, thus, the geometric constraints of the scanner design. Among other possibilities, this opens the possibility of using flat-panel PET detectors. Such a design would be more cost-accessible and compact and allow for a higher degree of modularity than a conventional ring scanner. However, achieving adequate CTR is a considerable challenge and requires improvements at every level of detection. Based on recent results in the ongoing development of optimised TOF-PET photodetectors and electronics, we expect that within a few years, a CTR of about 75 ps will be be achievable at the system level. In this work, flat-panel scanners with four panels and various design parameters were simulated, assessed and compared to a reference scanner based on the Siemens Biograph Vision using NEMA NU 2-2018 metrics. Point sources were also simulated, and a method for evaluating spatial resolution that is more appropriate for flat-panel geometry is presented. We also studied the effects of crystal readout strategies, comparing single-crystal and module readout levels. The results demonstrate that with a CTR below 100 ps, a flat-panel scanner can achieve image quality comparable to that of a reference clinical scanner, with considerable savings in scintillator material.