Amplitude Angle Research Articles

The impact of different treatments on thromboelastography and other conventional parameters in patients with colorectal cancer

ObjectiveTo comprehend the effects of diverse therapeutic interventions on thromboelastography (TEG) and conventional coagulation parameters among individuals diagnosed with colorectal cancer, this study aims to explore the clinical relevance of both thromboelastography and conventional coagulation metrics in evaluating coagulation function and predicting the incidence of thrombotic and hemorrhagic events in patients with colorectal cancer.MethodsA cohort of 122 patients with colorectal cancer retrospectively recruited and divided into 2 groups: those undergoing surgical intervention (operation group) and those not subjected to surgery (non-operation group). According to the different types of treatment they received, the operation group was divided into chemotherapy-only group and a group receiving a combination of targeted therapy and chemotherapy. Blood samples were collected on admission and subjected to coagulation parameter assessment, including conventional coagulation tests and thromboelastography (TEG) assessment. Receiver operating characteristic (ROC) analysis was performed to predict the occurrence of complications in patients with colorectal cancer.ResultsCompared with the operation group, the non-operation group showed significant reductions in reaction time(R-time) and kinetics time (K-time), and significant elevation in angle, maximum amplitude (MA), fibrinogen and platelets. Patients receiving targeted therapy and chemotherapy had lower angle and maximum amplitude and higher R-time and K-time, activated partial thromboplastin time and fibrinogen. The area under the curve for TEG in patients without treatment was 0.802. The area under the curve for TEG and conventional coagulation parameters were 0.654 and 0.660 respectively.ConclusionDiverse treatments distinctly impact on the coagulation indicators of individuals diagnosed with colorectal cancer. The coagulation parameters observed in patients prior to operation suggest a hypercoagulable state. Nevertheless, following postoperative chemotherapy and targeted therapy, this hypercoagulable state demonstrates a notable improvement, occasionally leading to a propensity for hypocoagulation. The findings of this investigation underscore the unique clinical importance of thromboelastography (TEG) alongside traditional coagulation parameters, demonstrating that these diagnostic tools possess complementary value and cannot be substituted interchangeably.

Studies on the free vibrations of tether of submerged floating tunnel involving tube motion by using different mechanical models

To accurately acquire the frequency/mode of the tethers of the tether-type submerged floating tunnel (SFT), which is an innovative underwater traffic structure with great potential, the dynamic frequency (DF) and wet mode (WM) of the tether involving the tube motion are studied. The novelty lies on the proposed novel method where the analytical relation of the tether’s DF and WM with the moving boundaries and the structural parameters is directly built. The gap that the unreported premise of quasi-static treatment for the global vibratory SFT and the unmentioned principle of the top tension of the tether equaling the net buoyancy within its supporting range is filled. Firstly, four mechanical models named M1∼M4 are respectively established by equating the tether as a beam or string with moving boundaries, taking into accounts the bending stiffness, wet-weight and other geometrical/material factors. Secondly, the relationships between the band-width, upper/lower limits of the DF and the inclination angle, vertical height, buoyancy-weight-ratio (BWR), motion amplitude are founded. Thirdly, the distribution laws of the DF during the vertical periodic motion of tube, as well as the parameter sensitivity range of the WM to the span-wise effect of wet-weight and the vertical height, are studied. The results show that the tether exhibits DF under the tube motion. The band-width of DF is sensitive to the BWR, inclination angle, vertical height and motion amplitude, and its upper/lower limits exhibit varying degrees of variation patterns with the changing of these parameters. The wet-weight and the vertical height are two main influencing factors of the WM. The proposed method provides a new treatment idea for further in-depth research on the locking zone of the vortex-induced vibration (VIV) and parametric vibration for the tether of SFT.

Numerical study of internal solitary wave loads on a submerged slender body with multi-parameter coupling

This study investigates the destabilizing loads exerted on submarines by large-amplitude internal solitary waves (ISWs), which significantly increase the risk of a phenomenon known as “falling deep.” Using numerical simulations and theoretical analysis, the research explores the multi-parameter coupling effects of ISWs on a slender body in a two-layer fluid system. A numerical wave generation method for large-amplitude ISWs, based on the strongly nonlinear adjusted high-order unidirectional (aHOU) model, is proposed. A corresponding numerical model is also developed to simulate the interaction between ISWs and a submerged slender body, with validation against experimental data confirming its accuracy and reliability. The study further examines how wave amplitude, submergence depth, and wave incidence angle affect the load characteristics induced by ISWs. Theoretical analysis identifies the components of ISW-induced loads, revealing a linear relationship between horizontal load and wave amplitude, as well as the influence of submergence depth on the duration of vertical forces. The primary contributor to the horizontal force is identified as the pressure-gradient force generated by the ISW's flow field, while the vertical force is primarily driven by the reduced gravity force due to density stratification and wave forces, which are well-approximated by Morison's formula. Additionally, the peak values of horizontal and vertical forces are significantly affected by wave incidence angle and wave amplitude, respectively. These findings provide a theoretical foundation for understanding the “falling deep” phenomenon encountered by submarines under the influence of ISWs.

Thromboelastography as an early prediction method for hypofibrinogenemia in emergency department patients with primary postpartum hemorrhage

BackgroundTimely and accurate assessment of coagulopathy is crucial for the management of primary postpartum hemorrhage (PPH). Thromboelastography (TEG) provides a comprehensive assessment of coagulation status and is useful for guiding the treatment of hemorrhagic events in various diseases. This study aimed to evaluate the role of TEG in predicting hypofibrinogenemia in emergency department (ED) patients with primary PPH.MethodsWe conducted a retrospective observational study in the ED of a university-affiliated tertiary hospital between November 2015 and August 2023. TEG was performed upon admission. The cutoff value for hypofibrinogenemia was 200 mg/dL. The primary outcome was the presence of hypofibrinogenemia.ResultsAmong the 174 patients, 73 (42.0%) had hypofibrinogenemia. The need for massive transfusion was higher in the hypofibrinogenemia group (37.0% vs. 5.0%, p < 0.001). Among the TEG parameters, all values were significantly different between the groups, except for lysis after 30 min, suggesting a tendency toward hypocoagulability. Multivariable analysis revealed that the alpha angle (odds ratio (OR) 0.924, 95% confidence interval (CI) 0.876–0.978) and maximum amplitude (MA) (OR 0.867, 95% CI 0.801–0.938) were independently associated with hypofibrinogenemia. The optimal cutoff values for the alpha angle and maximum amplitude (MA) for hypofibrinogenemia were 63.8 degrees and 56.1 mm, respectively.ConclusionPoint-of-care TEG could be a valuable tool for the early identification of hypofibrinogenemia in ED patients with primary PPH.

Ultrasonic testing method for impeller brazing defects with refraction wave perpendicular to brazing surface and angle amplitude compensation

Abstract There are blind areas in ultrasonic brazing defect detection, due to the non-parallel brazing surface and outer surface for many components including impeller. In this paper an oblique incident ultrasonic testing method with a refraction wave perpendicular to brazing surface is proposed. Meanwhile, an incident angle amplitude compensation is implemented to decrease the influence of the defect echo amplitude difference caused by oblique incidence and unify the sensitivity of different scanning positions. The compensation curve based on the theoretical curve of echo energy at different incident angles is optimized with iteration of actual measured defect echo amplitude. In order to prove the need for ultrasonic testing method with a refraction wave perpendicular to brazing surface, bottom surface echo test for conical samples is operated. In addition, with the method proposed in this paper, scanning image of impeller sample with the same detection sensitivity is obtained successfully. Testing results suggest that in relation to old method with incident wave perpendicular to the outer surface, the method proposed in this paper can solve the blind area problem effectively.

3D Morphological Feature Quantification and Analysis of Corn Leaves.

Marked variations in the 3-dimensional (3D) shape of corn leaves can be discerned as a function of various influences, including genetics, environmental factors, and the management of cultivation processes. However, the causes of these variations remain unclear, primarily due to the absence of quantitative methods to describe the 3D spatial morphology of leaves. To address this issue, this study acquired 3D digitized data of ear-position leaves from 478 corn inbred lines during the grain-filling stage. We propose quantitative calculation methods for 13 3D leaf shape features, such as the leaf length, 3D leaf area, leaf inclination angle, blade-included angle, blade self-twisting, blade planarity, and margin amplitude. Correlation analysis, cluster analysis, and heritability analysis were conducted among the 13 leaf traits. Leaf morphology differences among subpopulations of the inbred lines were also analyzed. The results revealed that the 3D leaf traits are capable of revealing the morphological differences among different leaf surfaces, and the genetic analysis revealed that 84.62% of the 3D phenotypic traits of ear-position leaves had a heritability greater than 0.3. However, the majority of 3D leaf shape traits were strongly affected by environmental conditions. Overall, this study quantitatively investigated 3D leaf shape in corn, providing a reliable basis for further research on the genetic regulation of corn leaf morphology and advancing the understanding of the complex interplay among crop genetics, phenotypes, and the environment.

Finite element simulations on delamination-induced local stress shielding effects on aseptic loosening behavior by bone remodeling

Interfacial damages (wear, delamination) and bone damage (remodeling, micro-cracks) can significantly affect the local bone deterioration and loosening of the acetabular cup. However, limited research has been conducted on both delamination and bone remodeling. This study aims to analyze the loosening behavior of an acetabular cup caused by the interaction of both interfacial damages and bone remodeling under different boundary conditions. A three-dimensional model of the acetabular cup was developed, and mechanically-induced remodeling behavior was implemented for the surrounding bone while the interfacial delamination between the cup and bone was modeled using the fracture mechanics approach. The delamination in the low initial bone mineral density (BMDs) cases encompasses almost the entire cup surface, which significantly affects the local bone remodeling process. The bone density near the top edge could be reduced to 20% in the lowest BMDs case which exaggerates the local strain accumulation and causes it to approach the micro-breaking limit. The loosening risk of the 45∘ fixation was reported in the low BMDs case which is a major limitation in conventional operation procedures for elderly patients. The interactive effect of the low BDMs, inclination angle, and loading amplitude can reduce the aseptic loosening life by half. This can be attributed to the amplified embedding of the acetabular cup caused by the delamination-induced reduction of the bone density. In future works, we aim to further consider anisotropic bone remodeling, microstructure of the bone, and delamination initiation behavior of surface coating.

Effect of interactive scalp acupuncture on upper limb function in patients with hemiplegia after stroke

To explore the clinical effect of interactive scalp acupuncture combined with task-oriented mirror therapy on hemiplegia after stroke. A total of 86 patients with hemiplegia after stroke were randomly divided into an observation group (43 cases, 2 cases dropped out) and a control group (43 cases, 2 cases dropped out). Both groups received routine treatment and rehabilitation treatment for stroke. The control group was treated with task-oriented mirror therapy, 40 min each time, once a day, 6 days a week. The observation group was treated with interactive scalp acupuncture at ipsilateral upper 1/5 and 2/5 of the parietal and temporal anterior oblique line and upper 1/5 and 2/5 of the parietal and temporal posterior oblique line on the basis of the treatment as the control group, 45 min each time, once a day, 6 days a week. Both groups were treated for 4 weeks. Before and after treatment and in follow-up of 8 weeks after treatment completion, the Fugl-Meyer assessment (FMA) score, modified Ashworth scale (MAS) score, shoulder abduction angle, wrist dorsiflexion angle and N20 latency and amplitude of somatosensory evoked potential were compared between the two groups. After treatment and in follow-up, the FMA scores were increased (P<0.01), the MAS scores were decreased (P<0.01) compared with those before treatment in the two groups; the FMA scores in the observation group were higher than those in the control group (P<0.01), the MAS scores were lower than those in the control group (P<0.01). After treatment and in follow-up, the shoulder abduction angle and wrist dorsiflexion angle was increased (P<0.01), the N20 latency was shortened and amplitude was increased (P<0.01) compared with that before treatment in both groups; the shoulder abduction angle and wrist dorsiflexion angle in the observation group was greater than that in the control group (P<0.01), the N20 latency was shorter than that in the control group (P<0.01), and the N20 amplitude was higher than that in the control group (P<0.01). Interactive scalp acupuncture combined with task-oriented mirror therapy can improve upper limb function in patients with hemiplegia after stroke, and reduce the muscular tone of the affected limb.

Utility of thromboelastography with platelet mapping for monitoring platelet transfusion in qualitative platelet disorders

BackgroundPatients with pathogenic variants in RASGRP2 (inherited platelet disorder (IPD)-18) exhibit normal platelet counts but impaired platelet aggregation and αIIbβ3 activation. Moderate-to-severe bleeding episodes require patients to be transfused with platelets and/or pro-hemostatic agents. We recently demonstrated that hemostatic efficacy of transfused platelets is limited by dysfunctional endogenous platelets in a mouse model of IPD-18 (Rasgrp2−/− mice), as dysfunctional platelets were recruited to the forming hemostatic plug but did not participate in clot contraction. Thus, higher amounts of transfused platelets were required to outcompete these dysfunctional cells and to reverse bleeding. ObjectiveWe here studied the usefulness of thromboelastography with platelet mapping (TEG-PM) for ex vivo monitoring of the hemostatic potential in Rasgrp2−/− mice transfused with various amounts of wild-type (WT) platelets. MethodsWhole blood (WB) samples from WT and Rasgrp2−/− mice were tested in TEG-PM and parameters for clot formation and contraction (K time, α-angle, maximum amplitude [MA]) were measured. ResultsRasgrp2−/− WB samples did not contract in TEG-PM, consistent with a critical role of this protein in αIIbβ3 activation. Addition of WT platelets improved TEG parameters in a ratio-dependent manner, consistent with our recent in vivo studies showing impaired hemostasis at a 5:1, but not at a 2:1 ratio of mutant to WT platelets. K and α values were identified as better predictors of transfusion efficacy than MA, the most platelet-dependent TEG parameter. ConclusionThis proof-of-concept study supports the use of TEG-PM to monitor platelet transfusion ratios and hemostatic potential in IPD-18 and potentially other platelet disorders.

Harmonic Self-Compensation Control for Bidirectional Grid Tied Inverter Based on Crown Porcupine Optimization Algorithm

A self-compensating control strategy for harmonic parameters based on the crown porcupine optimization algorithm is proposed for the single-phase rectifier and two-phase inverter operation mode of the bidirectional converter. In order to improve the response speed of the inverter voltage, the instantaneous expressions of the phase angle coefficient and amplitude coefficient of the dc-side voltage doubling fluctuation are derived, and the third harmonic is calculated based on the crown porcupine optimization algorithm according to the Proportional Integral (PI) + Quasi-Proportional Resonance (QPR) double closed-loop control method and injected into the input voltage of the inverter side to offset the influence of the bus-doubling fluctuation on the output voltage of the two-phase inverters of B and C so that the total harmonic content of the two-phase output voltages of the two-phase inverters of B and C can be reduced. The total harmonic content of the B and C inverter output voltages is reduced. The effective control of the control method for single-phase rectifier two-phase inverter mode is verified through simulation. Finally, the effectiveness of the control strategy is verified by experimenting with a 15 kW LCL-type bi-directional converter prototype.

Comparative digital study using four methods of measurements of the tibial distal anatomical axes for determining the anatomical-mechanical angle in dogs with cranial cruciate ligament rupture.

This study evaluates the amplitude of the anatomical-mechanical angle (AMA-angle) using 4 measuring methods of the tibial distal anatomical axes (DAA) previously described, comparing the literature results to determine if there are significant differences in patients with cranial cruciate ligament (CrCL) rupture. This study was comprised of 30 tibiae (29 dogs), including 1 bilateral case. A retrospective study was selected for this research. DAA measurements were performed on all surgically confirmed cases of canine CrCL rupture at Hospital Veterinário de Especialidades Bruselas from 2019 to 2022. Four different published methods (identified by surname of the corresponding author of the original publication) were compared. Tibial measurements were made using Veterinary Preoperative Orthopedic Planning Pro software (https://vpop-pro.com/) on mediolateral radiographic projections obtained from a digital database. The mean (range) in the DAA method conducted by Hulse obtained a AMA-angle of 5.4° (3.3 to 8.1°), 3.0° (0 to 5.8°) for Osmond et al, 3.2° (0.9 to 6°) for Miles, and 5.9° (2.4 to 8.8°) for Tudury. Differences among the means of the AMA-angle of the authors methods were found with a statistical difference (P < .05), except between Osmond and Miles. The mean AMA-angle with the Osmond method concurred with previous study results that determined the magnitude using the same measurement method of DAA in patients with CrCL rupture. The AMA-angle magnitude has been associated with higher sensitivity and specificity for predicting the development of CrCL rupture compared to other anatomical factors evaluated; therefore, future comparisons with different methods of measurement of the DAA between healthy and affected patients are recommended to determine whether any of them can increase the percentage value as a predictive factor for the occurrence of this condition.

A Photographic Approach Studying the Orientation of the occlusal plane of the Malaysian Population. A Proposal for an Orienting Device

The occlusal plane is crucial in prosthodontic reconstructive treatment as it affects the most important factors for the proper functioning of the artificial prostheses. The achievement of correct occlusal plane position offers maximum aesthetic, phonetic, mastication, and patient’s satisfaction. An incorrectly oriented occlusal plane interferes with denture stability and retention, in addition to more vital functions of the teeth and oral cavity. This study used a photographic approach to determine the occlusal plane inclination in relation to some anatomical references. 95 young volunteers of Mahsa University College, aged between 20 and 25 years, were selected for this study. The participants were selected according to specific inclusion criteria. A standardized digital profile and front images were taken for each participant using a digital camera that is fixed on a tripod with the fox bite plane placed on the occlusal surfaces of the maxillary teeth. The angle amplitude of the reference planes in relation to the occlusal plane was measured using a digital protractor on the screen display. The results revealed that the least mean angle difference was with the AT1, while higher variability was found using the Frankfort plane. In addition, there were no significant differences between the two genders or among the three ethnic groups. It is concluded that the photographic method can be used successfully to study the occlusal plane, and the lowest point of the tragus is the best posterior reference point to determine the ideal location of the occlusal plane.

The Effects of Sensor and Feature Level Fusion Methods in Multimodal Emotion Analysis

Fusion-based multimodal emotion recognition (MER) studies are very popular nowadays. In this study, EEG signals and face images are fused with sensor level fusion (SLF) and feature level fusion (FLF) methods for multimodal emotion recognition. The general flow of the study is as follows. Firstly, EEG signals are converted into angle amplitude graph (AAG) images. Secondly, the most unique ones are automatically identified from all face images obtained from video recordings. Then, these modalities are fused separately using SLF and FLF methods. The fusion approaches were used to combine the obtained data and perform classification on the integrated data. The experiments were performed with the publicly available DEAP dataset. The highest accuracy was 82.14% with 5.26 standard deviations for SLF and 87.62% with 6.74 standard deviations for FLF. These results show that this study makes a significant contribution to the field of emotion recognition by providing an effective method.

Kinetic‐Scale Current Sheets in the Solar Wind at 5 AU

AbstractWe present statistical analysis of 16,903 current sheets (CSs) observed over 641 days aboard Ulysses spacecraft at 5 AU. We show that the magnetic field rotates across CSs through some shear angle, while only weakly varies in magnitude. The CSs are typically asymmetric with statistically different, though only by a few percent, magnetic field magnitudes at the CS boundaries. The data set is classified into about 90.6% non‐bifurcated and 9.4% bifurcated CSs. Most of the CSs are proton kinetic‐scale structures with the half‐thickness of non‐bifurcated and bifurcated CSs within respectively 200–2,000 km and 500–5,000 km or 0.5–5λp and 0.7–15λp in units of local proton inertial length. The amplitude of the current density, mostly parallel to magnetic field, is typically within 0.05–0.5 nA/m2 or 0.04–0.4JA in units of local Alfvén current density. The CSs demonstrate approximate scale‐invariance with the shear angle and current density amplitude scaling with the half‐thickness, and . The matching of the magnetic field rotation and compressibility observed within the CSs against those in ambient solar wind indicate that the CSs are produced by turbulence, inheriting its scale‐invariance and compressibility. The estimated asymmetry in plasma beta between the CS boundaries is shown to be insufficient to suppress magnetic reconnection through the diamagnetic drift of X‐line. The presented results will be of value for future comparative analysis of CSs observed at different distances from the Sun.

Skeletal Anterior Open Bite Attenuates the Chewing-Related Increase in Brain Blood Flow.

The masticatory function of patients with skeletal anterior open bite (OPEN) is reported to be impaired compared with that of patients with normal occlusion (NORM). In this study, we compared brain blood flow (BBF) in patients with OPEN and NORM and investigated the factors related to BBF during mastication in patients with OPEN. The study included 17 individuals with NORM and 33 patients with OPEN. The following data were collected: number of occlusal contacts, jaw movement variables during mastication, and BBF measured with functional near-infrared spectroscopy during chewing. The number of occlusal contacts, maximum closing and opening speeds, closing angle, and vertical amplitude were smaller in the OPEN than in the NORM group. Interestingly, BBF increased less in the OPEN group. Correlation analysis revealed that several parameters, including number of occlusal contacts and closing angle, were correlated with changes in BBF during mastication. These results suggest that not only occlusion but also jaw movement variables and factors related to masticatory muscles contribute to the chewing-related increase in BBF. In conclusion, BBF increases less during mastication in patients with OPEN than in those with NORM. In addition, the higher increase in BBF is correlated with jaw movement. Together, we discovered that OPEN exhibits significant adverse effects not only on masticatory function but also on brain function.

Mechanical model of diamond wire sawing for curved surfaces

Diamond wire sawing is effective in machining complex parts. During the wire-cutting process, the cutting force affects the wire causing different shape changes, thereby affecting the machining quality. This paper introduces a wire sawing mechanical model for curved surfaces that considers the interdependence between the spatial motion of the wire, cutting force, and material removal. A wire bow angle measurement system was built using spring displacement sensors, and the accuracy of the mechanical model was verified through curved surface cutting experiments. The mechanical model was used to analyze the influences of the machining parameters and twist surface cutting process on the wire bow angle. The results showed that the sawing twisted surface increased the float amplitude of the wire bow angle. The wire feed rate at both ends varied with time owing to the wire twisting motion. The change in the wire feed rate at both ends was the primary factor affecting the change in the wire bow angle during the twist surface-sawing process. When sawing twisted, curved surfaces, the wire bow angle gradually decreases with increasing preloading force and wire velocity and a decreasing workpiece feed rate. Increasing the wire velocity and decreasing the workpiece feed rate can reduce the float amplitude of the wire bow angle, thereby enhancing the stability of the cutting process. This study lays the theoretical groundwork for understanding wire deformation during curved surface sawing.

Wake-induced torsional oscillation of two tethered cylinders for energy harvesting

When two cylinders submerged in a uniform flow are arranged in tandem, the downstream cylinder can oscillate in response to the wake from the upstream cylinder. In this investigation, the downstream cylinder is allowed to oscillate freely around the center of a fixed upstream cylinder, mimicking a pendulum-like motion. Our findings suggest that the wake stiffness concept, initially verified for relatively large cylinder spacing (ℓ≥4) and linear transverse cylinder motion, is also relevant for characterizing the wake-induced vibration (WIV) response observed for two tandem tethered cylinders situated in close proximity (2≤ℓ≤4) for Reynolds numbers in the range 1.0×104≲Re≲1.2×105, with tests conducted up to Re≈1.4×105. For small cylinder spacing (ℓ≤2.5), the downstream cylinder attains a maximum oscillation angle amplitude and exhibits consistent vibration, providing reliable potential for energy harvesting. We also explore hysteresis in the WIV response, which is observed to depend on the history of Reynolds number variation. Our findings reveal hysteresis at both the onset and termination of oscillation.

Friction, wear, and corrosion behavior of nitrocarburized HT250 gray cast iron

This study employed friction and wear experiments on nitrocarburized HT250 gray cast iron, utilizing GCr15 cemented carbide balls as the friction pair, to investigate the friction behavior and wear mechanism of the compound layer, diffusion layer, and matrix. The findings indicate that the diffusion layer exhibits the highest wear resistance, followed by the compound layer, while the matrix shows the lowest wear resistance. At lower loads, the wear form of the compound layer is characterized by minor flaking wear, the diffusion layer exhibits minor flaking and abrasive wear, and the matrix displays minor adhesive wear accompanied by abrasive wear. With increasing loads, the wear form of the compound layer transitions to flaking and abrasive wear, the diffusion layer shows fatigue flaking wear, and the matrix demonstrates severe adhesive wear, fatigue flaking wear, and abrasive wear. Electrochemical impedance spectroscopy and potentiodynamic polarization were employed to study the corrosion behavior of the compound layer, diffusion layer, and matrix in a 3.5 wt% NaCl solution. The results indicate a 27.7 % decrease in the corrosion current density of the compound layer compared to the matrix, with the diffusion layer exhibiting a corrosion current density two orders of magnitude lower than both the matrix and compound layer. In electrochemical impedance spectroscopy, the diffusion layer shows the highest impedance modulus, largest phase angle amplitude, and circular arc radius. It shows that the corrosion resistance of HT250 gray cast iron is improved after nitrocarburizing, especially the diffusion layer.

A Long-Range Signal-Based Target Localization Algorithm

Indoor target localization is pivotal across various applications, encompassing security monitoring, behavioral analysis, and elderly care. This work proposes an advanced target localization algorithm that harnesses antennas endowed with sensing capabilities to capture the phase change in the signal ratio, derived from the signal amplitude. This phase change, indicative of the target’s movement direction, is analyzed alongside the front and rear arrival angle information and signal amplitude characteristics obtained from LoRa signals. The algorithm, through a comprehensive examination of the phase change patterns, amalgamated with arrival angle data and signal amplitude characteristics, effectively estimates the precise location of the target. Experimental validations underscore the algorithm’s efficacy in determining the target’s location during continuous walking activity. Conducted within a 6 m × 12 m open platform, the algorithm achieves an average localization error of 48.5 cm, underscoring its superior performance compared to existing methodologies.

Electric-field induced droplet stable vertical vibration: Experiments and numerical simulations

In this study, stable vertical vibration of a single droplet was stimulated through Electrowetting on Dielectric (EWOD) on a Polydimethylsiloxane-coated Indium Tin Oxide glass (PDMS-ITO) surface in an oil atmosphere. The mechanism of the vibration is clarified as a self-adjusted energy earning and losing equilibrium, and a small friction at the contact line is crucial for this stable vibration. We investigated the impact of needle tip electrode height, different voltage forms (AC and DC voltages), and voltage magnitude on the droplet vibration state. As decreasing the needle tip electrode height, there is a transition of the droplet from a vibrating state to a static equilibrium state. During the vibration, the vibration period remains constant regardless of tip height, but the contact angle changes synchronously with the voltage. The electric signal in the circuit is also measured to provide solid evidence for this synchronicity. Finally, the saturation voltage of the contact angle and amplitude is about 120 V. The intrinsic connection between contact angle saturation and amplitude saturation is clarified by studying the surface energy of the droplet. A theoretical model is constructed to numerically simulate the shape and amplitude of the droplet’s vibrations.