Array Technique Research Articles

Combinatorial Method for Quality Improvement of the Thrust Plate – A Case Study

Aim: This research aims to mitigate defects in the turning operation of thrust plates used in fighter jet fuel tank assemblies, thereby reducing the rejection rate and improving overall quality. This aligns with the aerospace industry's reliability goals. Background: The thrust plate is a critical component in fighter jet fuel tank assembly, transmitting engine thrust to the airframe. Quality compromises in this component can impair jet performance. It was observed that the thrust plate had a rejection rate of about 2.9% due to various defects. This real- world scenario underscores the importance of our study on the thrust plate and its potential impact on the aerospace industry. The rejection rate underscores its significance and potential for patent by quality improvement in turning of the thrust plate. Objective: The objective is to mitigate turning operation defects on the thrust plate to reduce rejection rates, aligning with aerospace industry reliability goals. Methods: Experimentation encompassed four pivotal factors: turning speed, feed rate, cutting depth, and tool inserts, implemented through Taguchi's Orthogonal Array technique. Grey Relational Analysis was utilized to optimize parameters in thrust plate turning. Specifically, this paper targeted the enhancement of its diameter, surface roughness, and tool life. Results: A single coefficient for the multiple responses, i.e., grey relational grade, has been determined, and optimum levels for the parameters have been identified. Confirmation experiments with the optimal factor level combination were carried out on a sample of thrust plates, and no rejections were observed. Conclusion: An experimental design based on Taguchi’s orthogonal array approach was used to conduct the experiments. The Grey Relational Analysis has been applied to analyze the experimental results and optimize the turning operation process parameters for the responses thrust plate diameter, tool life, and surface roughness. With this, the rejection of the thrust plate has been considerably reduced.

Acoustic evaluation: microphone array measurements on a multi-megawatt individual pitch control wind turbine

As rotor diameters of wind turbines approach 200 m, aerodynamic noise becomes a significant issue, especially for onshore turbines. The rapid expansion of wind energy has led to increased concerns regarding the noise generated by wind turbines particularly in proximity to residential areas. This study investigates the noise emissions from a full-scale multi-megawatt individual pitch control (IPC) onshore wind turbine, with rotor diameter of 158 m and a hub height of 120 m, across 12 scenarios-six upstream and six downstream. The wind turbine under investigation operates under both IPC and non-IPC modes. Utilizing a microphone array and beamforming algorithm techniques, we conducted comprehensive acoustic measurements to analyses the noise sources and their characteristics. Our findings indicate that turbine operating in IPC mode produces higher sound pressure levels dB (A-weighted) as compared to the turbine under non-IPC modes. This observation emphasizes the need for a balanced approach in wind turbine operations, considering both load reduction and noise mitigation.

Localization of correlated moving sources from numerical flyover scenarios

The noise emissions during flyover test can be analyzed with a phased microphone array placed on the ground. If the flight path is known, an acoustic imaging technique is then used to map the sound pressure over the fuselage, in order to locate the most emergent aeroacoustic sources. Most of the dedicated array techniques assume a spatial distribution of uncorrelated equivalent sources to be sought. This paper deals with the localization of correlated moving sources, and demonstrates the effectiveness of an uncorrelated-based deconvolution technique for this purpose. The technique is applied on synthetic data from three different numerical scenarios, including a simplistic configuration of an overflying aircraft, which involve a small number of sparse, correlated monopoles in motion.

Recent Advances and Future Perspectives in Radiolabeled Antibody Fragments for Breast Cancer Molecular Imaging

Breast Cancer (BC) is the leading cause of cancer-related deaths in women and the most common cancer worldwide. It is classified based on its anatomical origin, the presence of Human Epidermal Growth Factor Receptor 2 (HER-2), and the presence of Estrogen Receptor (ER) and/or Progesterone Receptor (PR). Around 20% of breast cancers are HER-2 positive. While biopsy-based diagnoses are valuable in clinical settings, they have limitations in terms of sampling and interpretation. However, laboratory tests such as Immunohistochemistry (IHC) or Fluorescence In Situ Hybridization (FISH) are also limited, including being time-consuming, expensive, and requiring specialized equipment. Ongoing research and technological advancements aim to address the challenges associated with biopsy-based diagnoses and laboratory tests to develop more accurate and efficient methods for assessing HER-2 status. To this end, various radioactively labeled proteins and small compounds, such as single-chain variable Fragments (scFv), F(ab')2, affibody, and nanobody, have been developed to target HER-2 using molecular array techniques. These smaller targeted compounds offer improved image quality, shorter circulating half-life, and reduced immunogenicity compared to their larger counterparts. This is due to their better biodistribution, clearance, and stability. This study investigates the current understanding and ongoing efforts in utilizing antibody fragments for molecular imaging. The specific objectives were to evaluate the advantages of antibody fragments over full-length antibodies regarding biodistribution, clearance, and stability. Additionally, this study aims to assess the current knowledge and ongoing research in utilizing antibody fragments for molecular imaging.

Diagnostic value of six plasma biomarkers in progressive supranuclear palsy, multiple system atrophy, and Parkinson’s disease

ObjectivesThis study aimed to evaluate the diagnostic ability of six plasma biomarkers in progressive supranuclear palsy (PSP), multiple system atrophy (MSA), and different subtypes of Parkinson’s disease (PD). MethodsNeurofilament light chain (NfL), phosphorylated tau-181, glial fibrillary acidic protein (GFAP), amyloid-β 42 (Aβ42), and amyloid-β 40 (Aβ40) levels were measured using the single-molecule array (Simoa) technique in a cohort of patients with PSP, MSA, different subtypes of PD, and healthy controls (HCs). ResultsPlasma NfL and GFAP levels were beneficial in discriminating between the disease groups and HCs. Plasma NfL, Aβ42, and Aβ40 could distinguish atypical Parkinsonian syndrome (APS) from PD and its subtypes. GFAP could discriminate APS from tremor dominant PD but could not discriminate APS from postural instability and gait disorder dominant PD. The efficacy of differentiation improved when a combination of multiple plasma biomarkers was applied. ConclusionsIn this study, the plasma biomarkers NfL, GFAP, Aβ42, and Aβ40 exhibited high discriminatory diagnostic value in PD and APS, and could be used as clinically potential diagnostic biomarkers. Plasma biomarker combinations could improve the differential diagnostic efficacy in the comparisons of PD and APS.

Phase gradient metasurface for arbitrary three-dimensional shaped near-field

This paper proposes a methodology for generating arbitrary three-dimensional (3D) shaped near-field using phase gradient metasurface (PGMS) based on phase conjugation (PC) backtracking and shaped diffraction-free Bessel beam array techniques. The PGMS is designed by combining MATLAB and electromagnetic (EM) simulation software (CST). To the knowledge of the authors, for the first time, a 3D-shaped near-field is generated without increasing cost, structural and calculating complexity, and a methodology for generating arbitrarily shaped diffraction-free beam array is developed by MATLAB. To verify the technique, a planar PGMS is designed for dual x-polarized 3D-shaped near-fields: qq image “” in direction (θ1 = 5°, φ1 = 0°) and a flower image “” in direction (θ2 = 10°, φ2 = 180°). The advantages of the 3D-shaped near-fields are as follows: high conversion efficiency 30.5% (measured), wideband 60.5%, and low sidelobe -15 dB. The proposed technique is confirmed by the calculated, simulated, and measured results.

TNFα and IL-8 vitreous concentrations variations with two antidiabetic therapies in patients with proliferative diabetic retinopathy: an observational study

BackgroundAntidiabetic therapies are effective, but could indirectly modify the inflammatory response in the ocular microenvironment; therefore, a study was developed to evaluate the inflammatory cytokine profile in the vitreous humor of diabetic patients with retinopathy under treatment with antidiabetic drugs.MethodsObservational, comparative, retrospective, cross-sectional study. Interleukins 1β, 6, 8, 10, and tumor necrosis factor-alpha (TNFα) were evaluated in the vitreous humor obtained from patients with type 2 diabetes mellitus, proliferative diabetic retinopathy, and concomitant retinal detachment or vitreous hemorrhage, and who were already on antidiabetic treatment with insulin or metformin + glibenclamide. The quantification analysis of each cytokine was performed by the cytometric bead array (CBA) technique; medians and interquartile ranges were obtained, and the results were compared between groups using the Mann-Whitney U test, where a p-value < 0.05 was considered significant.ResultsThirty-eight samples; quantification of TNFα concentrations was higher in the group of patients administered insulin, while interleukin-8 was lower; in the metformin + glibenclamide combination therapy group, it occurred inversely. In the stratified analysis, the highest concentrations of interleukin-8 and TNFα occurred in patients with vitreous hemorrhage; however, the only statistical difference existed in patients with retinal detachment, whose TNFα concentration in the combined therapy group was the lowest value found (53.50 (33.03–86.66), p = 0.03). Interleukins 1β, 6, and 10 were not detected.ConclusionInterleukin-8 and TNFα concentrations are opposite between treatment groups; this change is more accentuated in patients with proliferative diabetic retinopathy and vitreous hemorrhage, where the highest concentrations of both cytokines are found, although only TNFα have statistical difference.

IKKε-deficient macrophages impede cardiac repair after myocardial infarction by enhancing the macrophage–myofibroblast transition

The regulatory role of the inhibitor of NF-kB kinase ε (IKKε) in postmyocardial infarction (MI) inflammation remains uncertain. Using an MI mouse model, we examined the cardiac outcomes of IKKε knockout (KO) mice and wild-type mice. We employed single-cell RNA sequencing (scRNA-seq) and phosphorylated protein array techniques to profile cardiac macrophages. IKKε KO mice exhibited compromised survival, heightened inflammation, pronounced cardiac fibrosis, and a reduced ejection fraction. A distinct cardiac macrophage subset in IKKε KO mice exhibited increased fibrotic marker expression and decreased phosphorylated p38 (p-p38) levels, indicating an enhanced macrophage–myofibroblast transition (MMT) post-MI. While cardiac inflammation is crucial for initiating compensatory pathways, the timely resolution of inflammation was impaired in the IKKε KO group, while the MMT in macrophages accelerated post-MI, leading to cardiac failure. Additionally, our study highlighted the potential of 5-azacytidine (5-Aza), known for its anti-inflammatory and cardioprotective effects, in restoring p-p38 levels in stimulated macrophages. The administration of 5-Aza significantly reduced the MMT in cardiac macrophages from the IKKε KO group. These findings underscore the regulation of the inflammatory response and macrophage transition by the IKKε-p38 axis, indicating that the MMT is a promising therapeutic target for ischemic heart disease.

Characterization of Shallow Sedimentary Layers in the Oran Region Using Ambient Vibration Data

This study investigates the structure of shear-wave velocities (Vs) in the shallow layers of the Oran region, north-west of Algeria, using non-invasive techniques based on ambient vibration arrays. The region has experienced several moderate earthquakes, including the historical Oran earthquake of 1790. Ambient vibration measurements were carried out at 15 sites throughout the study area. Two methods were used: spatial autocorrelation (SPAC) and frequency–wavenumber analysis (f-k), which allowed us to better constrain Rayleigh wave dispersion curves. The inversion of the dispersion curves derived from the f-k analysis allowed for estimating the shear-wave velocity profiles and the Vs30 value at the sites under study. The other important result of the present study is an empirical equation that has been proposed to predict Vs30 in the Oran region. The determination of near-surface shear-wave velocity profiles is an important step in the assessment of seismic hazard. This study has demonstrated the effectiveness of using ambient vibration array techniques to estimate the soil Vs structure.

A Geometric Phase Presetting Technique for CP Agile and Beam-Steering Reconfigurable Array With Enhanced AR Bandwidth

A Geometric Phase Presetting Technique for CP Agile and Beam-Steering Reconfigurable Array With Enhanced AR Bandwidth

Diagnostic and predictive power of plasma proteins in Alzheimer's disease: a cross-sectional and longitudinal study in China

Convenient and effective biomarkers are essential for the early diagnosis and treatment of Alzheimer’s disease (AD). In the cross-sectional study, 103 patients with AD, 82 patients with aMCI and 508 normal controls (NC) were enrolled. The single‐molecule array (Simoa) technique was used to assess the levels of plasma proteins, including NfL, T-tau, P-tau-181, Aβ40, Aβ42. Montreal Cognitive Assessment (MoCA) was used to assess the overall cognitive function of all subjects. Moreover, Amyloid PET and structural head MRI were also performed in a subset of the population. In the follow-up, the previous 508 normal older adults were followed up for two years, then COX regression analysis was used to investigate the association between baseline plasma proteins and future cognitive outcomes. NfL, T-tau, P-tau-181, Aβ40, Aβ42 and Aβ42/40 were altered in AD dementia, and NfL, Aβ42 and Aβ42/40 significantly outperformed all plasma proteins in differentiating AD dementia from NC, while NfL and Aβ42/40 could effectively distinguish between aMCI and NC. However, only plasma NfL was associated with future cognitive decline, and it was negatively correlated with MoCA (r = − 0.298, p < 0.001) and the volume of the left globus pallidus (r = − 0.278, p = 0.033). Plasma NfL can help distinguish between cognitively normal and cognitively impaired individuals (MCI/dementia) at the syndrome level. However, since we have not introduced other biomarkers for AD, such as PET CT or cerebrospinal fluid, and have not verified in other neurodegenerative diseases, whether plasma NFL can be used as a biomarker for AD needs to be further studied and explored.

Ultrasonic Imaging of Deeper Bone Defect Using Virtual Source Synthetic Aperture with Phased Shift Migration: A Phantom Study.

Ultrasound imaging for bone is a difficult task in the field of medical ultrasound. Compared with other phase array techniques, the synthetic aperture (SA) has a better lateral resolution but a limited imaging depth due to the limited ultrasonic energy emitted by the single emitter in each transmission. In contrast, the virtual source (VS) synthetic aperture allows a simultaneous multi-element emission and could provide a higher ultrasonic incident energy in each transmission. Therefore, the VS might achieve a high imaging quality at a deeper depth for bone imaging than the traditional SA. In this study, we proposed the virtual source phase shift migration (VS-PSM) method to achieve ultrasonic imaging of the deeper bone defect featured in the multilayer structure. The proposed VS-PSM method was validated using standard soft tissue phantom and printed bone phantom with artificial defects. The image quality was evaluated in terms of contrast-to-noise ratios (CNR) and amplitudes of scatters and defects at different imaging depths. The results showed that the VS-PSM method could achieve a high imaging quality of the soft tissues with a significant improvement in the scattering amplitude and without a significant sacrifice of the lateral and axial resolution. The PSM was superior to the DAS in suppressing the background noise in the images. Compared with the traditional SA-PSM, the VS-PSM method could image deeper bone defects at different ultrasonic frequencies, with an average improvement of 50% in CNR. In conclusion, this study demonstrated that the proposed VS-PSM method could image deeper bone defects and might help the diagnosis of bone disease using ultrasonic imaging.

An integrated atom array-nanophotonic chip platform with background-free imaging

Arrays of neutral atoms trapped in optical tweezers have emerged as a leading platform for quantum information processing and quantum simulation due to their scalability, reconfigurable connectivity, and high-fidelity operations. Individual atoms are promising candidates for quantum networking due to their capability to emit indistinguishable photons that are entangled with their internal atomic states. Integrating atom arrays with photonic interfaces would enable distributed architectures in which nodes hosting many processing qubits could be efficiently linked together via the distribution of remote entanglement. However, many atom array techniques cease to work in close proximity to photonic interfaces, with atom detection via standard fluorescence imaging presenting a major challenge due to scattering from nearby photonic devices. Here, we demonstrate an architecture that combines atom arrays with up to 64 optical tweezers and a millimeter-scale photonic chip hosting more than 100 nanophotonic cavities. We achieve high-fidelity ( ~ 99.2%), background-free imaging in close proximity to nanofabricated cavities using a multichromatic excitation and detection scheme. The atoms can be imaged while trapped a few hundred nanometers above the dielectric surface, which we verify using Stark shift measurements of the modified trapping potential. Finally, we rearrange atoms into defect-free arrays and load them simultaneously onto the same or multiple devices.

High gain quasi-omnidirectional dipole array fed by radial power divider for millimeter-wave IoT sensing

This article presents the design and implementation of a dipole array antenna based on a radial waveguide power divider for millimeter-wave IoT sensing applications. The dipole array and radial waveguide power divider techniques are used in tandem to achieve high gain with omnidirectional radiation properties. The proposed antenna is comprised of eight non-uniform array dipole structures, a circular radiating loop, and shorting vias. The one-to-eight power divider is created with the shorting vias to feed the circularly arranged eight non-uniform dipole arrays simultaneously. The proposed antenna is simulated and manufactured on Rogers-RO3003C substrate with a thickness of 8 mils. Both simulated and tested results confirm that the proposed method enables the antenna to offer a quasi-omnidirectional pattern with a high peak gain of 5.42 dBi. The antenna offers an impedance bandwidth (S11 < ‒ 10 dB) of more than 1 GHz ranging from 27.93 to 29.13 GHz. Moreover, by optimizing the parameters of the power divider network the proposed antenna can be tuned between a wide bandwidth range of 14.53 GHz as the designed dipole array offering the operating bandwidth from 25.56 to 40.09 GHz. Due to its comprehensive set of performance attributes, particularly for the quasi-omnidirectional radiation characteristics, the presented antenna is a viable candidate for the 5G millimeter wave wireless IoT sensing applications. Additionally, this work will accommodate other researchers to explore the proposed method for developing high-gain omnidirectional antennas for millimeter-wave applications.

Nonlinear Lamb wave phased array for revealing micro-damage based on the second harmonic reconstruction

It is challenging but meaningful to detect and image the micro-damage in the early stages of engineering structure failure. The nonlinear ultrasonic technique has gained considerable attention for micro-damage detection, meanwhile, the Lamb wave phased array technique has become a practical tool for macro-damage imaging. The combination of these two techniques can pave a promising way for micro-damage imaging in plate-like structures. However, the research on nonlinear Lamb wave phased array imaging is complicated and not reported. The weak nature and hard extraction of the nonlinear features, such as the second harmonic generation, limits the application of the nonlinear Lamb wave phased array. A framework of nonlinear Lamb wave phased array for micro-damage imaging in the plate-like structure is developed. To maximize the second harmonic response of the recorded Lamb waves, two kinds of lead zirconate titanate (PZT) wafers are selected to compose the nonlinear phased array. Furthermore, focusing on the nonlinear feature extraction, the sparse representation approach is introduced for reconstructing the time-domain second harmonic generated by the micro-damage, from which a wealth of waveform information corresponding to the micro-damage can be extracted. The total focusing method (TFM) is used for micro-damage imaging based on the reconstructed second harmonic. Numerical simulation and experimental validation demonstrate the capability of the proposed framework to image the local contact acoustic nonlinearity represented by the barely visible closed fatigue crack with the nonlinear Lamb wave phased array.

Quantitative and qualitative detection of target heavy metals using anti-interference colorimetric sensor Array combined with near-infrared spectroscopy

An anti-interference colorimetric sensor array (CSA) technique was developed for the qualitative and quantitative detection of target heavy metals in corn oil. This method involves a binding mechanism that triggers changes in atomic energy levels and visible color changes. A custom-built olfactory visualization device was employed to gather spectral data, revealing distinct CSA color difference patterns. Subsequently, three pattern recognition algorithms were used to create an identification model for the target heavy metals. The results showed that the ACO-KNN (Ant Colony Optimization-K-Nearest Neighbor) model outperformed the other models, achieving accuracy rates of 90.28% and 89.58% for the calibration and prediction sets, respectively. The ACO-PLS (Partial Least Square) model was more stable with the lowest root mean square error of prediction (RMSEP), which were 0.1730 and 0.1180, respectively. The limit of detection (LOD) and quantification (LOQ) of Pb and Hg were (0.3, 0.6, 1.1 and 2.2) x 10−3 mg/L, respectively.

ACE gene polymorphism and susceptibility to hypertension in a Jordanian adult population.

Hypertension is one of the most common and complicated disorders associated with genetic and environmental risk factors. The angiotensin-converting enzyme (ACE) is important in the renin-angiotensin-system pathway. The gene expression of ACE has been investigated as a possible hypertension marker. This study investigates the association between polymorphisms within the ACE1 and ACE2 genes and hypertension susceptibility in a Jordanian population. The study comprised a total of 200 hypertensive patients and 180 healthy controls. A polymerase chain reaction (PCR) was performed to genotype the candidate polymorphism (rs4646994) of the ACE1gene. The Luminex DNA array technique was used for genotyping SNPs (rs4359, rs4344, rs4341, rs4343, and rs2106809) of the ACE1 and ACE2 genes. Our findings suggest no association between SNPs and hypertension regarding allelic and genotypic frequencies. However, rs4359 was significantly associated with diet (pP = 0.049), know HTN (P = 0.042), and number of years DM (P = 0.003). rs4341 was associated with diet (P = 0.032), peripheral vascular disease (P = 0.005), and chronic kidney disease (p = 0.049). While rs4343 was associated with diet (P = 0.031), diabetes mellitus (P = 0.032), and other medication (P = 0.025). Furthermore, the haplotypes of four SNPs of the ACE1 gene showed no significant association with HTN patients and healthy controls. Our findings indicate no association between the polymorphisms in the ACE gene and the risk of hypertension development in the Jordanian adult population.

Comparison between PA and PWI/TFM Techniques for Non-Destructive Testing of Carbon Steel Weld

The Total Focusing Method (TFM) technique is an advanced Non-Destructive Testing (NDT) Ultrasonic Testing (UT) technique well known for its representative images of high resolution. It was firstly developed together with Full Matrix Capture (FMC) acquisition which can be substituted later by Plane Wave Imaging (PWI) acquisition for its improved acquisition speed and gain reserve without lowering the image quality. For these advantages, the PWI/TFM technique is tending to be more and more widely implemented. This article presents some results of the related study on PWI/TFM technique. Starting by PWI/TFM reconstruction principles, mainly on the influences of beam steering settings and corresponding inspection coverage in predefined Region of Interest (ROI), it focuses on the comparison on the indication amplitudes of planar discontinuities between classical Phased Array (PA) technique and PWI/TFM technique.

Improving the quality of performing in-service inspections using manipulators

Many in-service inspections, mainly carried out by the ultrasonic method, were until recently carried out manually or semi-automated with the use of encoders. These types of inspections usually lack data recording and are dependent on the experience of the operator performing these inspections. For these reasons, in recent years one of the important activities carried out within the Research Centre Rez has been the development and production of manipulators for non-destructive testing. This article will describe in more detail the manipulators used for ultrasonic testing of the reactor head nozzles, nozzles of the emergency power supply system of steam generators treated with weld overlay, inspection of low-pressure blade dovetails and others. The developed manipulators will make it possible to refine and improve the repeatability of inspections that were previously carried out manually (more precise guidance of probes, etc.) or were not carried out at all due to inaccessibility for operators. Among other examples of the use of manipulators is in conditions where manual testing is not possible. One of the applications can be measurement using the phased array technique on pipelines during service, when the temperature on the surface of the pipeline can be up to 320°C (the maximum temperature of the primary pipeline of a nuclear power plant).

Coil Array Technique With Maximum Tolerance to 2-D Misalignment for Wireless Power Transfer Systems

Coil Array Technique With Maximum Tolerance to 2-D Misalignment for Wireless Power Transfer Systems