Design Optimization Of Devices Research Articles

Simulated annealing algorithm for the optimal design of diffractive structures under fluctuation models

In this paper, to improve the optimization capability of the simulated annealing algorithm (SA) in the optimal design of diffractive structures, the random fluctuation problem in the algorithm is investigated, and a new fluctuation calculation model is proposed. The optimal design of phase-type diffraction gratings and beam-shaping devices verified the fast accuracy of the proposed model. The simulation experimental results show that the model’s introduction is particularly significant in substantially reducing computation time (a threefold increase in computation speed) and improving the algorithm’s optimization finding capability. Finally, the setting of the model parameters is discussed analytically to make the proposed model more applicable and robust. The study results provide guidance and assistance for higher speed and effectiveness in the optimal design using simulated annealing algorithms. It can be applied to any complex and large-scale optimization calculation problem.

Multidisciplinary Collaborative Design Optimization of Electric Shovel Working Devices

The development of the open-pit mining industry has set higher performance standards for mining electric shovels. Addressing issues such as low efficiency, high energy consumption, and high failure rates in working mining electric shovel devices, this paper comprehensively considers bulk mechanics, structural mechanics, and dynamics to conduct a multidisciplinary, collaborative design optimization for electric shovels by introducing the BLISCO method, which is based on an approximated model, into the structural-optimization design process of working electric shovel devices, aiming to enhance the overall performance of electric shovels. Firstly, a dynamic model of an electric shovel is established to analyze the hoist force and crowd force during the excavation process, and an accurate load input for the dynamic analysis is provided through the bulk material mechanics model. Additionally, to ensure that the stiffness of the boom meets the requirements, the maximum stress at the most critical position of the optimized boom is considered. Subsequently, the design variables are screened through experimental design, and an approximate model is established. Focusing on the hoist force, crowd force, maximum stress at the critical position of the boom, and the angle between the dipper arm and the wire rope, a mathematical model is constructed and optimized using a two-level integrated system co-optimization framework based on an approximate model (BLISCO-AM), followed by a simulation. Finally, a test bench for the electric shovel working device is constructed to compare pre- and post-optimization performance. Experimental results show that through the optimized design, the hoist force and crowd force required in a single excavation process are reduced by 6% and 8.48%, respectively, and the maximum angle between the wire rope and the dipper arm is increased by 4%, significantly improving excavation efficiency while ensuring the safety and reliability of the equipment.

Design optimization of a modified Uni-Traveling- carrier photodiode for high optical power operation

We systematically investigated the design optimization of an InGaAs/InP modified Uni-Traveling-Carrier Photodiode (MUTC-PD) under high optical power input conditions. Based on internally fabricated experimental devices for a baseline design, we first achieved an excellent match between our experimental and simulation results under low optical power density of 1.4 mW/μm2, demonstrating the accuracy of our simulation model. Based on this model we showed that as optical power injection increases, the intrinsic bandwidth of the MUTC-PD degradation is the primary limitation on its high-speed response. We quantitatively analyzed the fundamental carrier transport physics and key design parameters affecting intrinsic bandwidth degradation under these conditions. In particular cliff layer doping concentration was found to be a very sensitive parameter affecting the MUTC-PD Optical Electrical (OE) intrinsic bandwidth. Based on detailed simulated results, we realized an optimized device design that is capable of achieving a 3 dB bandwidth of approximately 230 GHz at 10 mW/μm2 input optical power density for the first time.

Mathematical model of ion chronogram from in-tube solid-phase microextraction device coupled with mass spectrometry and optimization framework

A mathematical description and experimental outputs exhibited that an ion chronogram from an in-tube solid-phase microextraction (SPME) device linked with mass spectrometry (in-tube-SPME-MS) generally appears as a right-skew unimodal signal with a heavy right tail. Analogous to liquid chromatography coupled with mass spectrometry (LC-MS), in-tube-SPME-MS can utilize the area under its produced ion chronogram for regression analysis and has been shown to be a potential approach for fast quantification of analyte. Different level of unimodity of signal in the ion chronogram could positively or negatively affect the choice of the area used for quantification and finally impact on analysis sensitivity and time efficiency of in-tube-SPME-MS. In the paper, we showed that different in-tube SPME design choices and elution experimental setups produce ion chronograms with controllable varying unimodal peak shape patterns. An improved mathematical model was built based on the plate theory of chromatography and the Van Deemter equation to quantitatively describe the elution process from in-tube-SPME device. A computer simulation was implemented to predict ion chronograms and the results were compared with experimental ion chronograms to show the effectiveness of the model. An optimization framework was further presented based on the model to identify optimal device designs (length and diameter of device) and experimental parameters (flow rate) to track targeted ion chronograms with “desired” peak shape patterns. Empirical elution experiments with the in-tube SPME devices adopting optimized geometric parameters and optimal experimental setups confirmed the consistency between the experimental ion chronograms and the numerical simulations to a certain level.

Design optimization of surface acoustic wave devices and investigation of fabricated devices under temperature, humidity and steam environments

Surface Acoustic Wave (SAW) technique is one of the most promising Micro Electro Mechanical Systems (MEMS) based detection methods for a variety of applications. SAW sensor is based on the modulation of Rayleigh waves that travel near the surface of a piezoelectric substrate. Advent of MEMS technology has led to the development of SAW sensors which are widely used in chemical sensing, medical, industrial, telecommunication and biological applications. The main focus of this paper is to devise and characterize a generic SAW structure and study the acoustic properties at various environmental conditions before depositing the sensing layer/analyte for any particular application. In this work, a SAW device was designed using COMSOL Multiphysics for a resonant frequency of 100 MHz with 40 μm wavelength on Lithium Niobate (LiNbO3) piezoelectric substrate. The optimized device structure was fabricated using thin film deposition and UV photolithography. The resonant frequency of the fabricated device (97.63 MHz) matched closely with the simulation results (100 MHz) and theoretical results (100 MHz). The device was subjected to various environmental conditions to study the influence on the resonant frequency. The SAW structure showed a resonant frequency shift of 90 KHz in steam environment, ∼ 1 MHz when heated to 150 °C and ∼ 120 KHz when exposed to 80% RH. The device exhibited a linear shift in resonant frequency under all tested environmental conditions with a consistent baseline and good repeatability.

Investigation of resistance performance of anti-icing wave-plate separators for marine gas turbines intake system

Abstract Due to their high power and efficiency, gas turbines are commonly used propulsion systems in hovercraft propulsion systems. In polar and cold marine environments, when a hovercraft rises, a significant number of droplets are generated on the water surface and are drawn into the gas turbine’s air intake with the cold air. This paper takes the structure of the original wave-plate separator as a reference and designs two structures: the rhombic anti-icing wave-plate separator (RAWS) and the streamlined anti-icing wave-plate separator (SAWS). Experimental and numerical simulation methods are employed to calculate the air intake resistance of the two structures at speeds ranging from 1 to 10 m/s. The results show that the K-ε standard enhanced wall function turbulent model is the closest to experimental measurements, with all calculated results having an error below 5%, demonstrating reliability. Compared to RAWS, the calculated total pressure loss for the SAWS structure decreases by 200 Pa under a designed air intake velocity of 7 m/s, representing a relative reduction of 40.8%. This provides a valuable reference for the design and resistance optimization of ship air intake anti-icing devices.

6‐1: Pragmatic low‐temperature polycrystalline thin‐film transistor technologies for high‐brightness and high‐temperature environments in AMOLED displays

This paper presents experimental and theoretical analysis of electrical characteristics for recent process‐based low‐temperature polysilicon (LTPS) thin‐film transistors (TFTs) in AMOED displays, focusing on high‐temperature and high‐luminance device characteristics. All off‐state current (Ioff) components in such conditions, which include gate‐induced drain leakage (GIDL), thermal generation, photo generation currents, are in detail analyzed. Exploring the effects of process technologies and device design in small‐size TFTs, in conjunction of reduced defect density‐of‐state (DOS) in the polycrystalline and its interface of gate oxide, we investigate optimal device and process design for reliable polycrystalline thin‐film transistor technologies in high‐brightness and high‐temperature situations. Numerical device simulations, supplemented by physics‐based analysis, confirm experimental results for our optimized device/process and gain diligent process/ design co‐optimization insights.

A Comprehensive Analysis of Reported Adverse Events and Device Failures Associated with Esophageal Self-Expandable Metal Stents: An FDA MAUDE Database Study.

Esophageal Stents are used to maintain esophageal lumen patency in esophageal strictures caused by intrinsic and/or extrinsic malignancies and the occlusion of concomitant esophageal fistulas. While data on the efficacy and safety of esophageal stents exist, comprehensive evaluation of adverse events is limited. The aim of this study is to investigate the reported adverse events and device failures associated with esophageal self-expandable metal stents (SEMS) using the FDA's Manufacturer and User Facility Device Experience (MAUDE) database. Post-marketing surveillance data for the esophageal SEMSs were analyzed using the FDA's MAUDE database from January 2014 to December 10, 2023. The outcomes of interest were patient-related adverse events and device failures. Statistical analysis was performed using Microsoft Excel 2010 and SPSS. Pooled numbers and percentages were calculated for each adverse event. Continuous variables underwent analysis using a two-tailed student t test, and significance was set to p ≤ 0.05. During the study period, 548 MAUDE reports revealed 873 device failures and 186 patient-related adverse events. The most common device issues were stent activation, positioning, or separation problems (4 n = 403; 46.2%), followed by device detachment or migration (n = 109, 12.5%), and material problems (n = 93, 10.7%). Patient complications included dysphagia/odynophagia (10%), perforation, pain, and bleeding (each 7.6%). The most common device failures in over-the-wire (OTW) stents and through-the-scope (TTS) stents were activation, positioning, or separation problems (TTS: n = 183, 52.6% vs OTW: n = 220, 41.9%). Compared to OTW stents, TTS stents had higher migration and breakage (13.5% vs. 11.8%, p = 0.24), and (9.2% vs. 6.7%, p = 0.08) respectively, while OTW stents had more challenges with stent advancement or removal (5.1% vs. 0.3%, p < 0.001 and 4.6% vs 3.4%, p = 0.19, respectively) and material problems (14.7% vs. 4.6%, p < 0.001). Activation, positioning, and separation problems were the most frequent device failures in fully covered (FC) and partially covered (PC) stents (FC: n = 62, 32.8%, PC: n = 168, 43.5%). FC stents had higher migration rates (20.6% vs 9.8%, p < 0.001), while PC stents exhibited more material problems (17.4% vs. 5.8%, p < 0.001) and difficulties with advancing the stents (6.7% vs. 0%, p < 0.001). Our examination showed a prevalence of reported device complications associated with stent activation, positioning, and separation problems. Dysphagia or odynophagia emerged as the most frequently reported patient complication. Furthermore, our analysis, provides insights into TTS vs. OTW and FC vs. PC esophageal SEMSs, enabling endoscopists and manufacturers to better understand adverse events and potentially optimize device design for future iterations.

Unlocking high stability in perovskite solar cells through vacuum-deposited Cs3Bi2I9 thin layer

Perovskite solar cells (PSCs) show great potential for efficient solar energy conversion, but their long-term stability is still a concern. To address this issue, we developed a vacuum-deposited bismuth-based perovskite-like material (Cs3Bi2I9), which forms a high-quality thin film showing remarkable stability over 150 days of air exposure. When combined with a solution-processed MAPbI3 perovskite, the resulting device exhibits improved stability under varying environmental conditions. However, the power conversion efficiency (PCE) drops by 70% compared to the reference MAPbI3-based PSC. An advanced multiphysics optoelectrical device simulation combining 3D FDTD and FEM methods validates these findings, yielding results in excellent agreement with the experimental data. The study also provides insight into the device’s optics and electronic properties, revealing the factors that limit its performance. An optimized device design is proposed to reach an 18.81% PCE, higher than the reference device. The findings have significant implications for developing next-generation solar cells, including high-performance tandem solar cells.

Equivalent single‐layer Mindlin theory of laminated piezoelectric plates and application

AbstractBased on the Mindlin first‐order shear deformation theory, this paper proposes an equivalent single layer (ESL) plate theory to analyze the electro‐mechanical coupling problem of laminated piezoelectric plates (LPPs). The main features of the proposed approach are: (i) It assumes that the electric potential across the thickness is a polynomial function, ensuring its continuity at the interface. (ii) The electric displacements are continuous at the interface, in line with the interface continuity condition between laminated plates. The theoretical solutions for the deformation and electric potential of LPPs are obtained. The validity and accuracy of the theoretical solutions are confirmed through comparison with results of two‐ and four‐layer LPPs obtained from the three‐dimensional finite element method (FEM). The numerical results discuss the influence of different series expansions and emphasize the necessity of high‐order expansion. Meanwhile, the range of application of three‐dimensional FEM is discussed. It is expected that such a new analytical method can be instructive to the optimal design of piezoelectric device.

Advanced characterization of SiC devices by optical beam induced current (OBIC): Experimental and simulation results

Wide-bandgap semiconductors, such as silicon carbide (SiC), gallium nitride (GaN), and diamond (C), have proven to outperform traditional silicon (Si) based power electronic devices. However, the peripheral protection of these wide-bandgap devices requires careful design to handle high voltage effectively. This article highlights the potential of using the Optical Beam Induced Current (OBIC) technique to analyze the effectiveness of different protection methods and provide valuable feedback to device designers regarding peripheral termination efficiency. Designers need simulations representative of the measurement, In this article a finite element simulation is used to determine the induced current as a function of the position of the optical beam.Firstly a theoretical approach will be presented to introduce the OBIC method. Subsequently, the electro-optical characterization technique is applied to a PiN diode protected by narrow field rings.The article also showcases new results obtained from components with new-generation peripheral protection, demonstrating the continuous progress in this field.Overall, this article highlights the significance of the OBIC technique in evaluating the effectiveness of peripheral protection methods for wide-bandgap semiconductors, particularly SiC devices. By providing valuable insights into the electric field's spatial distribution, this technique aids in optimizing device design and improving overall performance. Finite element simulations in relation to the characteristics of the UV beam and its scanning across the surface of the component help to assess the geometric parameter impact on the electrical results.

Boosting External Quantum Efficiency of Blue Perovskite QLEDs Exceeding 23% by Trifluoroacetate Passivation and Mixed Hole Transportation Design.

Perovskite quantum dot-based light-emitting diodes (QLEDs) have been considered a promising display technology due to their wide color gamut for authentic color expression. Currently, the external quantum efficiency (EQE) for state-of-the-art blue perovskite QLEDs is about 15%, which still lags behind its green and red counterparts (>25%) and blue film-based LEDs. Here, blue perovskite QLEDs that achieve an EQE of 23.5% at 490nm is presented, to the best knowledge, which is the highest value reported among blue perovskite-based LED fields. This impressive efficiency is achieved through a combination of quantum dot (QD) passivation and optimal device design. First, blue mixed halide perovskite CsPbCl3- xBrx QDs passivated by trifluoroacetate exhibit excellent exciton recombination behavior with a photoluminescence quantum yield of 84% due to reducing uncoordinated Pb surface defects. Furthermore, the device is designed by introducing a mixed hole-transport layer (M-HTL) to increase hole injection and transportation capacity and improve carrier balance. It is further found that M-HTL can decrease carrier leakage and increase radiative recombination in the device, evidenced by the visual electroluminescence spectrum at 2.0V. The work breaks through the EQE gap of 20% for blue perovskite-based QLEDs and significantly promotes their commercialization process.

Design and hydrodynamic study of a new pile-based breakwater-OWC device combined system

In order to enhance the conversion efficiency and optimize the hydrodynamic performance of the OWC device, a novel combined system composed of a pile-based OWC chamber and a perforated wave-eliminator is proposed. The schemes with rectangular front wall M1, elliptical front wall M2, M3 are designed. Physical tests and numerical simulations were conducted for the hydrodynamic process under the action of wave of the system with H/d = 0.16, 0.20, 0.24 and L/B = 3.3, 3.8, 4.3, 4.7, 5.2, 5.5, 6.4. The obtained-results show that the system has better energy converting and wave eliminating performance than the other existing systems. Its maximum conversion efficiency ξ is up to 70%, while its transmission coefficient Ct is less than 0.45. Compared to M1 and M2, M3 can improve the efficiency ξ of the system (up to approximately 35%) and reduce the maximum force exerted on the system (up to 10%). When studying the forces on the combined system, the horizontal force (in the direction of wave propagation) can be primarily calculated by considering the force exerted on the chamber. However, when investigating the vertical forces (opposite to gravity) acting on the system, both the OWC chamber and the wave-eliminator need to be considered. The research results can provide valuable references for further design optimization of OWC devices.

Trap-assisted tunneling in type II Ag2O/β-Ga2O3 self-powered solar blind photodetector

This study investigates a high-performance Ag2O/β-Ga2O3 self-powered photodiode through experimental and modeling approaches. Initially, a p-type Ag2O film, with a bandgap close to 4 eV and a hole density of approximately 6.35×1018 cm−3, was fabricated using faced two-target sputtering. The conduction and valence band offsets between Ag2O and β-Ga2O3 were determined via X-ray photoelectron spectroscopy, confirming a type II heterojunction. The device had a low on-voltage of 1.50 V and a low on-resistance of 5.40 mΩ.cm² in the dark. Subsequent illumination at 254 nm resulted in a notably high photocurrent, responsivity, and detectivity. To confirm the role of trap-assisted tunneling in the type II Ag2O/β-Ga2O3 heterojunction, Silvaco simulations were employed to model both the dark current and photocurrent. These simulations confirmed the prevalence of the trap-assisted tunneling mechanism, particularly through energy levels situated above the equilibrium Fermi level at the Ag2O/β-Ga2O3 interface, as described by the Danielsson model. Understanding the transport mechanism is paramount for the development of high-performance photodetectors. By comprehending how charge carriers navigate through the device and the influence of traps on their behavior, researchers can optimize device design and fabrication processes to enhance performance.

Influence of the Grid Inclination Angle on the Efficiency of Preliminary Separation of the Combed Heap

Introduction. A highly topical scientific and practical task is to justify the choice of the most advanced variant of the device for pre-separating the combed heap and to optimize its design. Aim of the Study. The study is aimed at testing the effect of the grid inclination angle on the effectiveness of pre-separating the combed heap. Materials and Methods. It is possible to minimize the separated grain flow into the threshing machine either by means of a feeder house grid bottom or by means of a horizontal separating device, located directly in front of the threshing drum. To select the optimal design of the separation device, there was planned and conducted a laboratory experiment. The study was carried out in two stages. In the first series of experiments, the elevator body was installed horizontally, and in the second series – at an angle of 45° to the horizon. The width of the grid bottom openings had four variations (6, 8, 10 and 12 mm), and the speed of the scraper conveyor was 3 m/s. A combed heap of the winter wheat variety Moskovskaya 56 was selected as the study object. The grain moisture was 12%. Results.According to the results of laboratory studies, it was found that with an increase in the width of the grid surface openings, the intensity of separating grain increases. The maximum device throughput (90%) corresponds to the horizontal position of the grid bottom of the experimental installation and the width of the openings b = 12 mm. Extrapolation of the separated grain decreasing graph indicates that to ensure complete separation of grain, the length of the separating grid should be at least L = 0.9 m. Discussion and Conclusion. The use of a horizontal separating grid allows increasing the device separation efficiency and reducing its metal content by 14–16%.

A Predictive Toxicokinetic Model for Nickel Leaching from Vascular Stents.

In vitro testing methods offer valuable insights into the corrosion vulnerability of metal implants and enable prompt comparison between devices. However, they fall short in predicting the extent of leaching and the biodistribution of implant byproducts under in vivo conditions. Physiologically based toxicokinetic (PBTK) models are capable of quantitatively establishing such correlations and therefore provide a powerful tool in advancing nonclinical methods to test medical implants and assess patient exposure to implant debris. In this study, we present a multicompartment PBTK model and a simulation engine for toxicological risk assessment of vascular stents. The mathematical model consists of a detailed set of constitutive equations that describe the transfer of nickel ions from the device to peri-implant tissue and circulation and the nickel mass exchange between blood and the various tissues/organs and excreta. Model parameterization was performed using (1) in-house-produced data from immersion testing to compute the device-specific diffusion parameters and (2) full-scale animal in situ implantation studies to extract the mammalian-specific biokinetic functions that characterize the time-dependent biodistribution of the released ions. The PBTK model was put to the test using a simulation engine to estimate the concentration-time profiles, along with confidence intervals through probabilistic Monte Carlo, of nickel ions leaching from the implanted devices and determine if permissible exposure limits are exceeded. The model-derived output demonstrated prognostic conformity with reported experimental data, indicating that it may provide the basis for the broader use of modeling and simulation tools to guide the optimal design of implantable devices in compliance with exposure limits and other regulatory requirements.

Design of Electrical Sheet Resistance of Thin Film Measurement System Based on GM Cryocooler in Cryogenic Temperature

The determination of the dependencies of the electrical resistivity of the thin film to temperature is of great importance both for understanding the conduction mechanism and for numerous technical applications of these films. In this work, to characterize, the electrical properties of thin films, a GM cryocooler-based automatic board temperature range electrical properties measurement system has been constructed. The system can measure multiple samples simultaneously. The cooling process was simulated using the time-discrete differencing to validate the optimized device design parameters and minimize heat losses. Furthermore, the temperature-dependent sheet resistance results were compared with the results from the physical property measurement system.

Electroosmotic microchannel flow of blood conveying copper and cupric nanoparticles: Ciliary motion experiencing entropy generation using backpropagated networks

AbstractA novel mathematical model for a hybrid (Cu–CuO/blood) Jeffrey nanofluid passing a vertical symmetric microchannel along with an electroosmosis pump is presented. The focuses on the advancement of mathematical modeling techniques, its comprehensive analysis of microfluidic system dynamics, and its potential to inform the optimal design of devices using nanofluids with broad applications in various fields. Arrhenius's law is used to analyze endothermic–exothermic reactions and activation energy. The governing partial differential equations of the fixed frame are transformed into ordinary differential equations of the wave frame using self‐similarity transformations. Low Reynolds number and long‐wavelength approximations helped to find solutions of the equations by applying a suitable BVP solver in MATLAB. The fluid's velocity, temperature, concentration, and electroosmosis properties are studied graphically. Two‐dimensional contour plots of fluid velocity and three‐dimensional surface plots of fluid properties are discussed. Physically significant quantities of mass transfer rate, skin friction coefficient, entropy generation, and heat transfer rate are studied using contour plots. Artificial neural network simulation using Bayesian regularization backpropagation algorithms is analyzed for training state, error histogram, fit, performance, and regression plots. Conclusively, the comprehensive analysis of the fluid dynamics, entropy generation, mass and heat transfer, and in the microchannel, coupled with the successful implementation of artificial neural network simulation, contributes to an improved understanding of the system's behavior. Entropy generation was raised for enhanced Brownian motion number and reduced values of thermophoresis, activation energy, and endothermic–exothermic reaction parameters. This study's results can be used to improve the efficiency and effectiveness of microfluidic devices used in fields as diverse as electrical cooling and medicine delivery.

A Bioinspired and Cost-Effective Device for Minimally Invasive Blood Sampling.

Conventional venipuncture is invasive and challenging in low and middle-income countries. Conversely, point-of-care devices paired with fingersticks, although less invasive, suffer from high variability and low blood volume collection. Recently approved microsampling devices address some of these issues but remain cost-prohibitive for resource-limited settings. In this work, a cost-effective microsampling device is described for the collection of liquid blood with minimal invasiveness and sufficient volume retrieval for laboratory analyses or immediate point-of-care testing. Inspired by the anatomy of sanguivorous leeches, the single-use device features a storage compartment for blood collection and a microneedle patch hidden within a suction cup. Finite Element Method simulations, corroborated by mechanical analyses, guide the material selection for device fabrication and design optimization. In piglets, the device successfully collects ≈195µL of blood with minimal invasiveness. Additionally, a tailor-made lid and adapter enable safe fluid transportation and integration with commercially available point-of-care systems for on-site analyses, respectively. Taken together, the proposed platform holds significant promise for enhancing healthcare in the pediatric population by improving patient compliance and reducing the risk of needlestick injuries through concealed microneedles. Most importantly, given its cost-effective fabrication, the open-source microsampling device may have a meaningful impact in resource-limited healthcare settings.

Thermal Impact Investigation of Shaded Opaque Walls in Bangkok

The effectiveness of overhang shading devices in mitigating solar radiation on opaque walls is crucial for passive building design in tropical regions. However, opaque walls commonly are side-lined in shading design due to a preoccupation with insulation properties, appearance, and aesthetics. Unprotected walls exposed to solar radiation maximize heat gain, while shaded walls decrease external heat gain and indoor temperature, resulting in improved indoor thermal comfort and well-being. This research employs EnergyPlus and SPSS to investigate the optimal design of overhang shading devices for opaque walls in Bangkok, Thailand. The investigation is divided into two phases: (1) determination of the optimal depth-to-space ratio of overhang devices based on a parametric study of 12 overhang configurations; (2) an evaluation of the ratio in reducing solar radiation. The findings demonstrate a relationship between the device depths and the wall solar radiation and indoor temperature. The optimum depth-to-space ratio is suggested as 1:1.15, which can lower the annual average indoor temperature by 3.53% (1.18°C) compared to the benchmark design. Deeper shading device depths than the optimum depth-to-space ratio can be applied, with a slight improvement in protective performance (and commensurately increased costs). This research underscores the importance of overhang shading devices as a performance-improving strategy for buildings in the tropical climate of Thailand.