Angle Dimensions Research Articles

Transmit–Receive Sparse Synthesis of Linear Frequency Diverse Array in Range-Angle Space Using Genetic Algorithm

Unlike conventional phased array (PA), frequency diversity array (FDA) can perform the beampattern synthesis not only in an angle dimension but also in a range dimension by introducing an additional frequency offset (FO) across the array aperture, thus greatly enhancing the beamforming flexibility of an array antenna. Nevertheless, an FDA with uniform inter-element spacing that consists of a huge number of elements is required when a high resolution is needed, which results in a high cost. To substantially reduce the cost while almost maintaining the antenna resolution, it is important to conduct a sparse synthesis of FDA. Under these circumstances, this paper investigated the transmit-receive beamforming of a sparse-fda in range and angle dimensions. In particular, the joint transmit-receive signal formula was first derived and analyzed to resolve the inherent time-varying characteristics of FDA based on a cost-effective signal processing diagram. In the sequel, the GA-based low sidelobe level (SLL) transmit-receive beamforming of the sparse-fda was proposed to generate a focused main lobe in a range-angle space, where the array element positions were incorporated into the optimization problem. Numerical results showed that 50% of the elements can be saved for the two linear FDAs with sinusoidally and logarithmically varying frequency offsets, respectively termed as sin-FO linear-FDA and log-FO linear-FDA, with only a less than 1 dB increment in SLL. The resultant SLLs are below -9.6 dB, and -12.9 dB for these two linear FDAs, respectively.

Application of a 2D interpolation technique to reduce the number of steering angles required for high-quality ultrasound images in plane-wave compounding

Plane wave imaging (PWI) can reach frame rates in the kHz range. However, PWI suffers from reduced image quality due to the lack of focusing. To tackle this limitation, plane wave compounding (PWC) was introduced. PWC is based on recombining multiple PWI images generated using different steering angles. However, the number of steering angles required to achieve reasonable image quality significantly reduces the frame rate. In this study, we propose a two-dimensional (2D) interpolation technique, based on radial basis functions, which allows reducing the number of steering angles in PWC without degrading image quality. The idea is to reduce the number of steering angles and then apply 2D interpolation, along the angle dimension and directly to the RF data, to reconstruct the data related to those angles for which data were not collected. The full dataset is then utilized to generate an image. To compare this technique with standard PWC, we utilized the dataset from the Plane-wave Imaging Challenge in Medical UltraSound (PICMUS). The results show that the number of steering angles can be reduced by factor 3, thus tripling the frame rate, while achieving comparable performance with standard PWC (with 75 angles) in terms of contrast and spatialresolution.

Aortic root rotational position associates with aortic valvar incompetence and aortic dilation after arterial switch operation for transposition of the great arteries.

Aortic dilation and valvar regurgitation can develop in transposition of the great arteries (TGA) after the arterial switch operation (ASO). Variation in aortic root rotational position affects flow dynamics in patients without congenital heart disease. The aim of this study was to assess neo-aortic root (neo-AoR) rotational position and its association with neo-AoR dilation, ascending aorta (AAo) dilation, and neo-aortic valvar regurgitation in TGA following ASO. Patients with TGA repaired by ASO who underwent cardiac magnetic resonance (CMR) were reviewed. Neo-AoR rotational angle, neo-AoR and AAo dimensions indexed (to height), indexed left ventricular end diastolic volume (LVEDVI), and neo-aortic valvar regurgitant fraction (RF) were obtained from CMR. Among 36 patients, the median age at CMR was 17.1 years (12.3, 21.9). Neo-AoR rotational angle (range - 52 to + 78°) was clockwise ( ≥ + 15°) in 50%, counterclockwise (<-9°) in 25%, and central (-9 to + 14°) in 25% of patients. A quadratic term for neo-AoR rotational angle, indicating increasing extremes of counterclockwise and clockwise angles, was associated with neo-AoR dilation (R2 = 0.132, p = 0.03), AAo dilation (R2 = 0.160, p = 0.016), and LVEDVI (R2 = 0.20, p = 0.007). These associations remained statistically significant on multivariable analyses. Rotational angle was negatively associated with neo-aortic valvar RF on univariable (p < 0.05) and multivariable analyses (p < 0.02). Rotational angle was associated with smaller bilateral branch pulmonary arteries (p = 0.02). In patients with TGA after ASO, neo-AoR rotational position likely affects valvar function and hemodynamics, leading to a risk of neo-AoR and AAo dilation, aortic valvar incompetence, increasing left ventricular size, and smaller branch pulmonary arteries.

Experimental and numerical investigations of block shear failure in gusset plates welded to double angle members

Double angle braces are used extensively in structures to resist lateral loads such as wind, earthquake, and blast loads. A possible failure mode in the gusset plate when all-around weld is used for the angles is the block shear failure. To date, only limited test data on welded gusset plates failing in this mode have been reported in the literature, and all of them only considered concentrically loaded gusset plates. This paper investigates the block shear failure in welded gusset plates experimentally and numerically when connected to double angle members with possible in-plane load eccentricity effects. The test results, including failure loads, fracture sequences, and load-displacement responses are reported in detail. Results showed that tensile fracture was initiated adjacent to the angle heel weld and then propagated along the tension plane. Due to existing in-plane load eccentricity, shear planes did not rupture simultaneously and the shear plane adjacent to the heel weld failed earlier. Following the testing, a numerical investigation using nonlinear finite element analyses with ductile damage capability was performed on the tested specimens. Subsequently, a parametric study was carried out to generate further numerical data over a wide range of gusset and angle dimensions, welding configurations, and connection lengths. Accordingly, the existing design equations for block shear strength as given by AISC specification were evaluated. It was shown that AISC provides excessively conservative and scattered failure loads because of ignoring stress triaxiality and using shear yield instead of shear rupture in its strength equations. In addition, equations specified for welded gusset plates by previous studies were considered and shown to be unsafe for general use. To address these shortcomings, an improved block shear strength equation is proposed in this paper and shown to predict the gusset strength in block shear with improved accuracy.

Range-angle-dependent beamforming for FDA radar with Hamming interelement spacing and sinusoidal multicarrier approach

By employing a tiny frequency offset across the array elements, a frequency diverse array (FDA) produces a beampattern with the property of being range-angle-dependent. However, the beampattern of a traditional FDA has many maxima at undesired range-angle couples, which is unfavorable for target localization and jamming suppression. In this paper, a novel FDA scheme with Hamming interelement spacing, namely, the HIS-FDA, is proposed. By adopting Hamming window weighted interelement spacing and frequency offsets optimized by the genetic algorithm, the HIS-FDA produces a dot-shaped well-performed beampattern, which has superior performance over the existing FDA systems, especially in the angle dimension. The multiple input multiple output technique and multiple matched filters are employed at the receiver to solve the time-varying problem. A new multicarrier (MC) technique termed the sinusoidal MC approach is also presented to improve the beampattern performance, especially in the range dimension. Our proposed scheme outperforms the existing FDA systems in terms of the mainlobe width in the range and angle profiles, the sidelobe level, and the range-angle spatial region of the mainlobe. Comparison results are provided to validate the superiority of the proposed scheme.

A Study on the Performance of the Shock Absorption Friction Spring using Finite Element Analysis

The characteristics of friction springs are different before and after the spring is contacted with the inner and outer rings; their applications vary from defense to aerospace industries. Recently, the frequency of using friction springs to replace hydraulic shock absorbers used in high-load areas has been increasing according to the weight reduction and miniaturization of the system. In this research, the performance of friction springs often used to alleviate impact force, such as vertical shock absorbers, was analyzed through computational analysis. Changes in the major performance factors of the friction spring were investigated according to the elastic modulus of the material constituting the friction spring and the friction coefficient between the rings. Through theoretical analysis, it was confirmed that the results of previous studies and simulations showing the tensile and return stiffness of friction springs as a function of friction coefficient, elastic modulus, taper angle, and spring dimensions showed similar trends.

Retinal Vascular Geometry in Hypertension: cSLO-Based Method.

We aim to introduce a method using confocal scanning laser ophthalmoscopy (cSLO) images for measuring retinal vascular geometry, including vessel branch angle (BA), vessel diameter, vessel tortuosity, and fractal dimension (Df), and to elucidate the relationship between hypertension and these metrics. A total of 119 participants (119 eyes) were enrolled, among which 72 were normotensive and 47 were hypertensive. Infrared cSLO images were extracted from the circular scan around the optics disc using a commercial cSLO + optical coherence tomography instrument. Preprocessed cSLO images were further analyzed using the appropriate tool/macro/plugin of ImageJ. Intraclass correlation coefficients of selected methods used for conducting the cSLO-based geometric analyses were all higher than 0.80. Arterial/arteriolar BA, arteriolar vessel diameter, and total Df in normotensive subjects were 85.80 ± 7.79°, 116.80 ± 12.58μm, and 1.430 ± 0.037, respectively, significantly higher than those of hypertensive subjects (82.13 ± 10.83°, 108.2 ± 11.12μm, and 1.361 ± 0.044, all P < 0.05). The aforementioned metrics remained negatively correlated with hypertension even after adjusting for age alone or age and gender (P < 0.05). However, the difference between arteriolar tortuosity and all studied venous/venular geometric parameters in both subjects was insignificant (all P > 0.05). Proposed cSLO-based methods for assessing various vascular geometric parameters were highly repeatable and reproducible. Arterial/arteriolar BA, arteriolar vessel diameter, and total Df were retinal vascular parameters significantly correlated with hypertension in a negative manner.

Maxillary Sinus Dimensions in Skeletal Class I Chinese Population with Different Vertical Skeletal Patterns: A Cone-Beam Computed Tomography Study.

Due to the close relationship between the maxillary posterior teeth roots and the maxillary sinus floor, the maxillary sinus can significantly impact various dental treatments, including endodontic procedures and surgical apicectomy, periodontal flap surgery, surgical tooth extraction, dental implantation, and orthognathic surgeries. Specifically, in orthodontics, the location of the maxillary sinus floor may affect tooth movement and insertion of temporary anchorage devices (TADs). This study aims to evaluate the dimensions and location of the maxillary sinus in the Chinese orthodontic patient population with skeletal class I. Using cone-beam computed tomography (CBCT), the volumetric size, height, width, and depth of the sinus and the amount of alveolar bone below the sinus floor and buccal/palatal to the sinus wall were compared between patients of different genders and different vertical skeletal patterns. Unlike the previously reported skeletal class II population, the skeletal class I patients with different vertical patterns do not have significantly different size sinuses. On the other hand, males have larger maxillary sinuses in all parameters than females in the testing population. In addition, no significant correlation was noticed between the SN-MP angle and sinus dimensions or between the ANB angle and sinus dimensions. Nevertheless, the distance from the sinus floor to the alveolar bone crest is not correlated with skeletally sagittal or vertical parameters in females but negatively correlated with the skeletal sagittal parameter in males. In summary, different from the skeletal class II population, there is no significant difference in maxillary sinus size and location among different vertical skeletal patterns in the skeletal class I population. Compared to the skeletal class II population, a higher percentage of the skeletal class I population has an alveolar bone with less than 5 mm thickness, representing a narrowed safe zone of TADs placements.

Target anisotropic scattering deduction model using multi-aspect SAR data

Typical targets in SAR observing scenes are characterized by anisotropy, which represents backscattering information changing with the observing angle. Anisotropic scattering can be used to study the structural characteristics of targets and the response differences between structures. In actual situations, due to flight conditions and other reasons, only partial observation information can be obtained, so it is important to use limited data to deduce remaining backscattering information for target analysis. In our article, the scattering deduction model based on matrix completion is established, including scattering characteristic analysis. The multi-aspect data is transferred from range and azimuth in conventional SAR image to pixel dimension and angle dimension for analysis. At the same time, the pixel similarity matrix is used as a feature in pixel dimension, and one-dimension back-amplitude scattering curve with angle is established as a feature matrix in angle dimension. In the process of modeling existing data, two corresponding decomposition matrices are generated with the help of collaborative filtering idea. Finally, a four-matrix combination for anisotropy deduction is formed. Ku-band multi-aspect data from autonomous experimental flights is used for algorithm. In the experiment, the scattering deduction of the remaining aspect sequence was carried out based on obtaining partial aspect sequence images, and the strong scattering regions of the target point and sub-aperture details were compared. The edge information and structure map of the target were reconstructed using scattering deduction results.

Bending responses of CFRP thin-walled tubes with different sectional shapes: Experimental, analytical and numerical investigation

The stiffness, elastic ultimate load and failure mode of carbon fiber reinforced plastic (CFRP) thin-walled square tube (ST), chamfered square tube (CST) and circular tube (CT) with the same circumference under transverse bending load were compared and analyzed. The load-displacement curves, strain-time curves and video images were recorded throughout the process of quasi-static bending to capture the initiation and propagation of failure. Based on the shear-deformable beam and planar curved rod deformation theory, the analytical models for evaluating the integral stiffness and local stiffness of CFRP thin-walled tube were established respectively. The failure mechanisms of ST, CST and CT were further revealed by developing finite element model. The effects of boundary condition, ply orientation angle, geometric dimension and indenter shape on bending properties of CFRP thin-walled tubes were studied. According to the failure characteristics of CST and CT, the indenters that can increase the contact zone were designed and tested. The complete failure of ST was caused by split cracks extending and web buckling, while that of CT was malposed cracks spreading and wall collapsing. The local stiffness of ST and the integral stiffness of CT were the optimum among three specimens. The elastic ultimate load of CST and CT could be improved by adopting 45° layers and the designed indenters. The boundary condition correction coefficient was calculated and fitted utilizing numerical total stiffness and analytical integral stiffness, contributing to explore the ply orientation angle and geometric dimension design space of CST stiffness parameters.

Remanence deviations in permanent magnet synchronous machines evaluated using a model order reduction approach

AbstractIn this article remanence deviations of a permanent magnet synchronous machine are studied with the proper orthogonal decomposition (POD). The design of experiments enables to create designs with a reduced sample size compared to full factorial designs without decreasing the stochastic significance of the remanence distributions. Next, a POD basis is created with the belonging design, that is distinctly smaller than the reference. From the POD basis the projection matrix is built to compute the flux density solutions. The machine's output is then analyzed regarding accuracy originating from numerical errors. Different parameters are evaluated and compared to the reference to appraise the accuracy of the flux density solutions, which includes the POD basis size, rotor angle step size and dimension of the reduced system. Results show, that the most influence has the dimension of the reduced system. Depending on the dimension and other parameters about one quarter of computational effort can be conserved without a significant loss in accuracy.

Torsional effect of the single-bay masonry building considering seismic wave incident angle

Single-bay masonry building is the main structure form of rural houses in Southwest China. In the investigation of earthquake damage in Lushan earthquake, it is found that this type of structure has serious torsional damage. In this paper, the torsional effect was verified with 1/6 scale model while the torsional responses of some actual size models were simulated by self-compiled program. Under the coupling action of translation and torsion, the effects of seismic wave incident angle and structural geometric dimension on the torsional response of structure were analyzed. The results showed that the incident angle of seismic wave and the structural irregularity were the important reasons which caused the torsional failure of the structure. When the incident angle of the seismic wave was about 60°, the torsional response of the structure was the strongest. Besides, in order to reduce the influence of torsional effect, the eccentricity ratio should be smaller than 6%, and the number of storey should better be three or less.

Predicting CT-Based Coronary Artery Disease Using Vascular Biomarkers Derived from Fundus Photographs with a Graph Convolutional Neural Network.

The study population contains 145 patients who were prospectively recruited for coronary CT angiography (CCTA) and fundoscopy. This study first examined the association between retinal vascular changes and the Coronary Artery Disease Reporting and Data System (CAD-RADS) as assessed on CCTA. Then, we developed a graph neural network (GNN) model for predicting the CAD-RADS as a proxy for coronary artery disease. The CCTA scans were stratified by CAD-RADS scores by expert readers, and the vascular biomarkers were extracted from their fundus images. Association analyses of CAD-RADS scores were performed with patient characteristics, retinal diseases, and quantitative vascular biomarkers. Finally, a GNN model was constructed for the task of predicting the CAD-RADS score compared to traditional machine learning (ML) models. The experimental results showed that a few retinal vascular biomarkers were significantly associated with adverse CAD-RADS scores, which were mainly pertaining to arterial width, arterial angle, venous angle, and fractal dimensions. Additionally, the GNN model achieved a sensitivity, specificity, accuracy and area under the curve of 0.711, 0.697, 0.704 and 0.739, respectively. This performance outperformed the same evaluation metrics obtained from the traditional ML models (p < 0.05). The data suggested that retinal vasculature could be a potential biomarker for atherosclerosis in the coronary artery and that the GNN model could be utilized for accurate prediction.

Theoretical analysis on thermal grease dry-out degradation in space environment

Silicone thermal grease can reduce the contact thermal resistance of thermal interfaces and has been widely used as a thermal interface material in the thermal design of spacecraft. Silicone thermal grease gradually degrades owing to the dry-out of silicone oil during a long service period and breaks the validity of the thermal interface and induces thermal overload in a spacecraft. In this study, a mechanism-based prediction method for the silicone thermal grease loss in a space environment is proposed. The prediction of long-term thermal grease loss is realised by evaluating the variation in its effective thermal conductivity. In the prediction method, an improved multi-component thermal conductivity model was established to determine the thermal conductivity of thermal grease with multiple filler sizes and a high filler volume fraction. Then, the silicone oil loss induced by complex penetration, crawl, and volatilisation were evaluated with an equivalent capillary model and a volatilisation model. The behaviour of the silicone oil loss, the primary cause of dry-out degradation, was clarified. The variation in the effective thermal conductivity of thermal grease under different contact angles, operating temperatures, and connection surface dimensions was investigated. The results show that the dominant factor gradually changes from capillary loss to volatilisation loss during dry-out degradation. The effective thermal conductivity decreased faster at higher operating temperatures, and the effective thermal conductivity decreased slower with an increase in the contact angle and connection interface dimensions. The present work provides insights for the design of silicone thermal greases for space utilization.

Rotating object detection in remote-sensing environment

Deep learning models have become the mainstream algorithm for processing computer vision tasks. In the tasks of object detection, the detection box is usually set as a rectangular box aligned with the coordinate axis, so as to achieve the complete packaging of the object. However, when facing some objects with large aspect ratio and angle, the bounding box must be enlarged, which makes the bounding box contain a large amount of useless background information. In this study, a different approach based on YOLOv5 is adopted. By this means, the angle information dimension is added at the head, and angle regression is also added at the same time of the boundary regression. Then the loss of the boundary box is calculated by combining ciou and smoothl1, so that the obtained boundary box is more closely suitable for the actual object. At the same time, the original dataset tags are also pre-processed to calculate the angle information of interest. The purpose of these improvements is to realize object detection with angles in remote-sensing images, especially for objects with large aspect ratios, such as ships, airplanes, and automobiles. Compared with the traditional and other state-of-the-art arbitrarily oriented object detection model based on deep learning, experimental results show that the proposed method has a unique effect in detecting rotating objects.

Range–Angle Transceiver Beamforming Based on Semicircular-FDA Scheme

Incontrast to the steady angle-dependent transmit beampattern of the conventional phased array, the counterpart of a frequency diverse array (FDA) is basically time variant and range–angle coupled, which limits its potential application in many scenarios. In this article, we consider the beamforming in joint transmit and receive domains to handle the time-variant problem and propose a novel range–angle transceiver beamforming approach based on the semicircular-FDA scheme. In particular, the transceiver scheme of semicircular-FDA is first established.In the sequel, the periodicities of its transceiver beampattern in range and angle dimensions are briefly analyzed. Based on this analysis, a semicircular-FDA applied with nonlinearly increasing frequency offset (NIFO), termed as NIFO semicircular-FDA, is proposed to achieve the beampattern with a single mainlobe peak in range–angle space. Then, an optimization problem is constructed based on an advanced bat algorithm to further reduce the sidelobe level (SLL) of the NIFO semicircular-FDA. Numerical results show that focused time-invariant beampattern with low SLL in both range and angle dimensions can be achieved with the proposed approach.

Optical Efficiency Analysis of Primary Mirror in LFR-CSP

The linear Fresnel solar thermal power generation system is one of the most representative forms of solar thermal power generation system at present. The primary mirror, as the main mirror, plays a key role in the photothermic conversion process of the collector tube. In this paper, the solar position and the optical efficiency of the primary mirror in LFR-CSP are modeled and analyzed. The light reflection process of primary mirror by solar position through four dimensions of solar declination angle, solar time angle, altitude angle and azimuth angle is studied, and the distribution law of solar position parameters in different seasons and different times throughout the year is analyzed. It is found that the variation range of chord efficiency of a single mirror element in the whole day is 75 %-93 %. The position of a mirror element in winter solstice has the greatest impact on the end loss of more than 1 %, but the summer solstice has no effect.

Evaluation of the Effects of Distal Malocclusion Activators on the Craniofacial Complex

Introduction: Class II malocclusions are the most commonly seen, and therefore, the most commonly treated type of anomalies. Dental and skeletal factors are involved in the development of Class II malocclusions. The purpose of this study was to investigate whether or not there were any changes in the increased cranial base angle and cranial base dimensions, which have been reported to be among the morphological characteristics of Class II malocclusions, with functional orthopedic treatment and to evaluate effects of these changes on facial structures. Materials and Methods: The study was conducted on hand-wrist radiographs and lateral cephalometric radiographs of 50 patients taken at the beginning and at the end of treatment. The control group comprised 17 patients and the treatment group comprised 17 patients who were treated with a Class II division 1 activator and 16 patients who were treated with a combination of Class II division 1 activator and an Occipital Headgear (Hg). Results: Among the measurements for cranial base dimensions, only the increase in S-N in the treatment group was smaller than that in the control group. No significant differences were found among groups regarding the values of NSBa and NSAr angles, which are known to be cranial base angles. Conclusion: The increase in the S-N dimension being smaller in the treatment group brings about the idea that the activator treatment may influence maxillary development and consequently the nasomaxillary complex.

Optical Coherence Tomography to Assess Proximal Side Optimization Technique in Crush Stenting.

AimThe aim of this study was to explore the potential intraprocedural benefits of the Proximal Side Optimization (PSO) technique by Optical Coherence Tomography (OCT).MethodsA case series of 10 consecutive true bifurcation lesions, with severe long pathology of long side branch (SB), were randomly assigned to be treated by standard DK Crush procedure (non-PSO group) as compared to DK Crush in PSO modification (PSO group). The data from OCT investigation before crushing of the SB Drug-Eluting Stent (DES), after crushing, after first kissing balloon inflation (KBI), and after final angiography were compared between the two groups (Public trials registry ISRCTN23355755).ResultsAll 10 cases were successfully treated by the assigned technique. The two groups were similar in terms of indications for the procedure, bifurcation angle, and stent dimensions. As compared to the non-PSO, the PSO group showed larger proximal SB stent areas (5.8 ± 1.8 vs. 4.5 ± 0.5 mm2; p = 0.02), the larger delta between distal and proximal stent areas before crush (1.5 ± 0.7 vs. 0.6 ± 0.5 mm2; p = 0.004), and the larger Space of Optimal Wiring (SOW) after Crush (5.3 ± 1.8 vs. 2.5 ± 1.1 mm2; p = 0.02). The gaps in scaffolding within the ostial segment of the Side Branch DES were found in two patients from the non-PSO group.ConclusionThe DK Crush in PSO modification results in larger SB DES and SOW areas with better apposition to the vessel wall. As result, the SB DES acquires a funnel shape, which reduces the risk of passage outside the SB stent struts during re-wiring, thus, allowing predictable and secure results.

Surface milled by CAD-CAM system Vs laboratorial methods to simulate the milled surface: Effect on the resin bond strength to lithium disilicate glass-ceramic

The aim of this study was to assess the resin microshear bond strength (μSBS) and the surface topography of lithium disilicate ceramic milled by CAD/CAM and to compare it with in-lab methods that simulate the topography of milled surfaces; thus, assessing the feasibility of those in-lab methods for in vitro microshear studies. The study was composed of 2 control groups (CAD/CAM group – discs were milled by a CAD/CAM system; POL – polished ceramics surface) and 4 testing groups (SiC – manual grinding simulation with #60 silicon carbide paper; WS – manual grinding with #60 wood-sandpaper; DB – grinding with a fine cylindrical diamond bur; MANDREL – grinding with a CAD/CAM bur coupled to a mandrel). After production, the ceramic samples were crystallized. Surface treatment with hydrofluoric acid (HF) and silane was performed on the bonding surface, then the starch matrices were filled by the resin cement and light-activated. The specimens (n= 45) were submitted to μSBS after 24 h of storage in water (37° C) and the failure pattern was analyzed. Topographic analysis, surface roughness, contact angle, and fractal dimension were performed. One-way ANOVA and Tukey's post-hoc tests were run for roughness, while Bonferroni’ post hoc was used for μSBS data. Fractal dimension data was qualitatively assessed. No difference was found in the μSBS between in-lab simulation methods and the milled group, while the polished group presented the lowest μSBS values. The CAD/CAM milled specimens presented the highest roughness values, while the POL the lowest ones. In regards to surface complexity, no difference was found among all simulated groups and the CAD/CAM group, with an exception for the POL group. All conditions presented an increase in surface complexity after HF etching. Therefore, the resin bond strength to lithium disilicate glass-ceramic is not influenced by the in-lab simulation method, meaning they are predictable approaches when evaluating the resin bonding to the tested ceramic; the surface polishing underestimates the bond results in ∼40%.