Search Results (103)

A new compact, wideband, millimeter-wave microstrip crossover—designed without vias—demonstrates effective performance with an insertion loss of 2 dB across a wide frequency range. For Path 1, the operational bandwidth spans 11 GHz (13–24 GHz), while for Path 2, it extends over 10 GHz (12–22 GHz). The overlapping bandwidth, maintaining the 2 dB insertion loss criterion, covers 9 GHz (13–22 GHz). The design introduces two transition mechanisms to achieve optimal scattering parameters for the crossover: a stair-shaped microstrip line (MST) to ground-backed coplanar waveguide (GCPW) for the initial crossed line (Path 1), and vertical coupling between microstrip and coplanar hourglass microstrip patches on a single-layer substrate for Path 2. This innovative approach ensures an insertion loss of approximately 1 dB for both paths across the bandwidth, with a slight increase beyond 20 GHz for Path 2 due to substrate losses. Both crossed lines maintain a return loss of 10 dB across the spectrum, with isolation of approximately 20 dB. This design presents a flat, compact, and via-less configuration, with physical dimensions measuring 6.5 mm × 7.6 mm. The proposed design exhibits excellent scattering parameters, which enhance the efficiency of phased array antenna systems in terms of power transfer between input and output ports, as well as improving isolation between different input ports in the feed network of these systems used in remote sensing. Consequently, this contributes to the increased sensitivity and accuracy of such systems. Full article

The purpose of this study was to investigate the benefits of a 12-week plyometric training program intervention on lower limb joint mobility, explosive strength, advanced layup success rates, and injury rates. The study recruited 15 collegiate male basketball players as participants. They underwent basketball training five times per week, each lasting two hours, and additionally received plyometric training twice a week. The study utilized image processing software (ImageJ, version 1.54f, National Institutes of Health, Bethesda, MD, USA) to measure the lower limb joint mobility during the take-off phase of a layup and employed a force plate to assess the explosive strength of the lower limbs during the jump. Furthermore, the study examined the success rate and injury rate of advanced layups—including crossover layups, spin layups, and straight-line layups—as well as the sports injury rate. The results demonstrated that plyometric training significantly enhanced the hip, knee, and ankle joint mobility as well as lower limb explosive strength, with a strong positive correlation between these variables. Furthermore, plyometric training improved joint mobility and lower limb explosive strength. The success rate of advanced layups increased from 50% to 72%, while the sports injury rate decreased from 18% to 8%. In conclusion, plyometric training significantly improved participants’ lower limb joint mobility and explosive strength, which in turn enhanced advanced layup performance and reduced the sports injury rate. Although this study provided preliminary evidence supporting the effectiveness of plyometric training, further research is needed to examine its long-term effects and other influencing factors. Full article

Objective: The objective of this study is to compare the long-term outcomes of femorofemoral crossover bypass (FCOB) and endovascular treatment (ET) in managing iliac artery occlusions. Methods: The data of 200 patients with iliac artery lesions who were treated at a single center within 7 years were evaluated retrospectively. Of these, 82 (41%) underwent FCOB, and 118 (59%) received ET. Primary outcomes included patency, limb salvage, and survival rates, while secondary outcomes assessed complications, including wound infections and restenosis. Follow-up was conducted over a median of 4.98 years. Results: Primary patency (PP) rates after 3 years were 80% for FCOB and 88% for ET. Primary assisted patency (PAP) was 95% for FCOB and 93% for ET. Secondary patency (SP) was 97% for FCOB and 98% for ET. Both FCOB and ET achieved comparable long-term outcomes in limb salvage, 94% in both groups at 8 years. ET demonstrated advantages in shorter hospital stays (1.49 ± 2.51 vs. 8.21 ± 9.82 days, p < 0.0001) and lower perioperative complications, including transfusion rates (3.4% vs. 13.4%, p = 0.01226). However, FCOB exhibited lower restenosis rates (6.1% vs. 20.39%, p = 0.00441), despite a higher rate of reocclusion (19.5% vs. 6.8%, p = 0.00800). Survival rates at 8 years were 54% for FCOB and 67% for ET. Conclusions: ET is the preferred first-line approach due to its minimally invasive technique, shorter recovery time, and fewer complications. FCOB remains essential for patients with complex lesions or when ET is not feasible, offering durable long-term outcomes. Appropriate treatment selection should consider both the patient’s condition and clinical and anatomical factors to optimize the best possible patient outcomes. Full article

Compared to conventional pulse-limited altimeters (i.e., low-resolution mode, LRM), the synthetic aperture radar (SAR, i.e., high-resolution mode, HRM) altimeter offers superior precision and along-track resolution abilities. However, because the SAR altimeter relies on Doppler shifts caused by the relative movement between radar scattering points and the altimeter antenna, the geophysical parameters obtained by the SAR altimeter are sensitive to the direction of ocean wave movements driven by the wind and waves. Both practice and theory have shown that the wind and wave effects have a greater impact on HRM data than LRM. LRM values of range and significant wave height (SWH) from modern retracking are the best representations there are of these quantities, and this study aims to bring HRM data into line with them. In this study, wind and wave effects in SAR altimeter measurements were analyzed and corrected. The radar altimeter onboard the Sentinel-6 satellite is the first SAR altimeter to operate in an interleaved open burst mode. It has the capability of simultaneous generation of both LRM and HRM data. This study utilizes Sentinel-6 altimetry data and ERA5 re-analysis data to identify the influence of ocean waves. The analysis is based on the altimeter range and SWH differences between the HRM and LRM measurements with respect to different geophysical parameters derived from model data. Results show that both HRM range and SWH measurements are impacted by SWH and wind speed, and the HRM SWH measurements are also significantly impacted by vertical velocity. An upwave/downwave bias between HRM and LRM range is observed. To reduce wave impact on the SAR altimeter measurements, a back-propagation neural network (BPNN) method is proposed to correct the HRM range and SWH measurements. Based on Sentinel-6 measurements and ERA5 re-analysis data, our corrections significantly reduce biases between LRM and HRM range and SWH values. Finally, the accuracies of the sea surface height (SSH) and SWH measurements after correction are assessed using crossover analysis and compared against NDBC buoy data. The standard deviation (STD) of the HRM SSH differences at crossovers has no significant changes before (3.97 cm) and after (3.94 cm) correction. In comparison to the NDBC data, the root mean square error (RMSE) of the corrected HRM SWH data is 0.187 m, which is significantly better than that with no correction (0.265 m). Full article

This paper explores how competing interactions in the intermolecular potential of fluids affect their structural transitions. This study employs a versatile potential model with a hard core followed by two constant steps, representing wells or shoulders, analyzed in both one-dimensional (1D) and three-dimensional (3D) systems. Comparing these dimensionalities highlights the effect of confinement on structural transitions. Exact results are derived for 1D systems, while the rational function approximation is used for unconfined 3D fluids. Both scenarios confirm that when the steps are repulsive, the wavelength of the oscillatory decay of the total correlation function evolves with temperature either continuously or discontinuously. In the latter case, a discontinuous oscillation crossover line emerges in the temperature–density plane. For an attractive first step and a repulsive second step, a Fisher–Widom line appears. Although the 1D and 3D results share common features, dimensionality introduces differences: these behaviors occur in distinct temperature ranges, require deeper wells, or become attenuated in 3D. Certain features observed in 1D may vanish in 3D. We conclude that fluids with competing interactions exhibit a rich and intricate pattern of structural transitions, demonstrating the significant influence of dimensionality and interaction features. Full article

In recent years, the rapid expansion of subway construction has brought increasing challenges related to the crossing of new and existing subway lines. This study focuses on the Nanjing Metro line 11 project, where the new line crosses the existing line 3. A numerical simulation analysis of the tunnel intersection area is conducted using ABAQUS software to investigate the deformation mechanism of shield segments when a new tunnel is constructed at a close distance and oblique angle to an existing tunnel. During the construction of a new tunnel, the existing tunnel segments experience the greatest settlement at the intersection point, with the deformation pattern gradually evolving from a V-shape to a W-shape. The majority of the deformation in the existing tunnel occurs during the close-crossing stage of the new tunnel. An ultra-high-performance grouting (UHPG) material is proposed, and the optimal reinforcement material ratio is determined through tests. The UHPG material is applied to the underside of the existing tunnels in the crossover section for local reinforcement. The results demonstrated the effectiveness of the proposed reinforcement method. Specifically, the deformation of the left line and right line of the existing tunnel is reduced by 35.0% and 33.1%, respectively, the segmental stress decreased by 10.1%, and the ground subsidence was reduced by 13.2%. Full article

Background/Objectives: The movement and vibration of the body’s soft tissues during dynamic exercise are mechanisms that attenuate force from ground impacts. However, repeated exposure to such vibrations over time can contribute to the development of lower-body soreness and/or injuries. The previous literature has established the benefit of compression garments for the minimisation of soft tissue movement during running, though little is known about this mechanism during other forms of dynamic exercise. The current study aimed to investigate the effect of compression tights on lower-body soft tissue movement during jumping, sprinting and change-of-direction tasks typical of those found in team sports. Methods: In a randomised crossover design, twelve recreationally active males (age 26 ± 2 years) completed countermovement jumps, drop jumps from 45 cm, 10 m straight line sprints and change-of-direction tasks wearing either commercially available sports compression tights or regular exercise tights. Marker-based motion capture was used to quantify soft tissue displacement at the thigh and calf and lower-body kinematic variables during the exercise tasks. Results: No significant (p < 0.05) differences were observed between conditions for soft tissue displacement at the thigh and calf and performance variables for all tasks. There were significant (p = 0.003) differences in peak knee flexion and hip flexion during the 10 m sprint and change-of-direction task between conditions; however, effect sizes were unclear. Conclusions: Compression tights do not appear to influence soft tissue movement or performance during sports-specific forms of locomotion but may alter some kinematic aspects of sprinting and change-of-direction tasks compared with regular exercise tights. Full article

Precise positioning of non-cooperative targets is important for maintaining spacecraft operational environments in orbit. In order to address the challenges of non-cooperative target localization during non-coplanar rendezvous, this study develops a distributed cooperative localization scheme. First, a three-line-of-sight positioning method for long-range targets in non-coplanar orbits is proposed. Second, a distributed extended Kalman filter based on a consensus algorithm is designed, which reduces observation dimensions and increases system robustness. Subsequently, the rendezvous configuration optimization problem for long-range non-coplanar targets is transformed into a numerical optimization problem. Finally, an improved NSGA-III algorithm is proposed by introducing normal distribution crossover (NDX) and a cosine-like mutation distribution index to optimize the rendezvous configuration. A simulation shows that the methods proposed are effective, and the improved NSGA-III is superior to traditional algorithms in terms of search range and convergence speed. After configuration optimization, the performance of the system has been greatly improved, with better positioning accuracy and stronger robustness. Full article

This paper proposes a multi-objective nonlinear model predictive control (MOMPC) method based on an improved non-dominated sorting genetic algorithm II (NSGAII) for the path tracking problem of unmanned surface vehicles (USVs). To enhance performance in cross-track error, a varying look-ahead distance is utilized in the line of sight (LOS) algorithm, which allows the MPC control algorithm to compute the look-ahead distance and desired speed rather than directly calculating the control input. Since the cost function of the MPC algorithm includes multiple objective terms, a multi-objective model predictive control algorithm is employed to improve overall control performance. Additionally, an adaptive rotation-based simulated binary crossover (ARSBX) is integrated into the NSGAII algorithm, and the non-dominated sorting method is optimized to reduce computation time. These enhancements increase diversity and exploration in the solution space, enabling the algorithm to find the optimal solution more efficiently. Simulations conducted in two different scenarios demonstrate that the nonlinear MPC method based on the improved NSGAII successfully tracks the desired path; it achieved an improvement of approximately 41% in time performance and about 5% in path-tracking error performance, exhibiting strong control performance and robustness. Full article

Background and Objectives: The proprotein convertase subtilisin-kexin type 9 (PCSK9) inhibitors evolocumab and alirocumab are recently developed promising drugs used for treatment of familial hypercholesterolemia (FH). This systematic review and meta-analysis aimed to thoroughly evaluate the efficacy and safety of evolocumab and alirocumab among pediatric patients with FH. Materials and Methods: A comprehensive search was conducted in PubMed, Embase, CENTRAL (Cochrane Central Register of Controlled Trials), and ClinicalTrials.gov from inception through July 2024 to identify primary interventional studies among pediatric patients with FH. Meta-analyses were performed if appropriate. Statistics were analyzed using Review Manager version 5.4 and Stata version 16.0. Results: Fourteen articles reporting nine unique studies were included. There were three randomized controlled trials (RCTs) assessing evolocumab or alirocumab involving a total of 320 pediatric patients, one cross-over trial and five single-arm or observational studies. Pooled results showed significant efficacy of evolocumab/alirocumab in reducing low-density lipoprotein cholesterol (LDL-C) (weighted mean difference [WMD]: −37.92%, 95% confidence interval [CI]: −43.06% to −32.78%; I² = 0.0%, p = 0.60), apolipoprotein B (WMD: −33.67%, 95% CI: −38.12% to −29.22%; I² = 0.0%, p = 0.71), and also lipoprotein(a) (WMD: −16.94%, 95% CI: −26.20% to −7.69%; I² = 0.0%, p = 0.71) among pediatric patients with FH. The efficacies of evolocumab/alirocumab on LDL-C reduction within pediatric patients with heterozygous FH (HeFH) were consistent between studies, whereas in patients with homozygous FH (HoFH), it varied dramatically. Pediatric patients with the null/null variant may respond to the treatment. PCSK9 inhibitors were generally well tolerated within most pediatric patients, in line with previous studies among adult populations. Conclusions: The PCSK9 inhibitors evolocumab/alirocumab significantly reduced LDL-C and some other lipid parameters, such as apolipoprotein B, in pediatric patients with HeFH. These drugs may be appropriate as a potential therapy for pediatric patients with HoFH who cannot achieve LDL-C targets with other treatments. Evolocumab/alirocumab was generally well tolerated in the pediatric population. Full article

In this study we consider correlated and simultaneous interventions regarding: i—the physical infrastructure (by crossover lines between the two tracks of a tram line), ii—the characteristics of the trams (by bi-directional trams), as well as iii—tactical and operative decisions of the line manager. How these interventions are reflected in the functional reliability of the tram line service is demonstrated for both cases of the current operation and for the case of overloads, respectively, for the case of the temporary degradation of circulation caused by random disruptive events. The theoretical analysis, generalizing findings regarding the effectiveness of solutions to improve functional reliability, is supplemented with quantitative evaluations related to certain situations of disruptions. The proposed solutions aim to increase the attractiveness of urban public transport. Even if the evaluations are focused mainly on the interests of the service quality perceived by the user, the beneficial consequences for the line manager (in terms of technical and commercial efficiency) are also addressed. Full article

This paper proposes a microwave rectifier designed for the popular 5G band, featuring impedance dispersion compensation and a cross-type impedance matching network. The rectifier has an ultra-high power conversion efficiency. The compensation network employs two parallel transmission lines to counteract the nonlinear shift of the diode input impedance caused by frequency variation. Additionally, the cross-over impedance matching network enhances matching and minimizes losses. After rigorous theoretical analysis and simulation, the rectifier is fabricated. Experimental results show significant conversion efficiency in the 5G band (across 4–6.5 GHz). At an input power of 12 dBm, the rectifier achieves more than 60% efficiency between 4.8 and 6.4 GHz and more than 70% between 5.2 and 6.2 GHz, with a peak efficiency of 78.1%. Moreover, the rectifier maintains more than 50% efficiency over a wide input power range of 5 to 14 dBm. Full article

This paper presents a frequency-reconfigurable dual-band radio frequency (RF) crossover based on quarter-wavelength coupled lines (CLs) and open stubs. Initially, an even–odd-mode analysis was conducted for the design, and closed-form equations were found. Then an advanced design system (ADS) was utilized to support and further optimize the theoretical analysis. Afterwards, high-frequency simulation software (HFSS) was used to simulate the proposed design. The proposed device is printed on a 1.524 mm RO4003C printed-circuit board (${\epsilon }_r=3.55)$. The frequency tunability is achieved by employing two varactor diodes connected to the open stubs. When the biasing voltage is altered, the capacitance of the SMV1405 varactor can change from 2.67 pF to 0.63 pF. Accordingly, the two operating frequencies can be continuously tuned from 2.06 GHz to 2.40 GHz and from 5.44 GHz to 5.84 GHz. For the low-frequency range, return loss and isolation are above 15 dB, and the insertion loss is less than 1.1 dB. As for the high-frequency range, the return loss is greater than 20 dB, the isolation is better than 15 dB, and the insertion loss is lower than 1.6 dB. The measurement results agreed well with the simulation results, and the crossover overall size is 45.5 mm $\times$ 29.4 mm. The proposed device can be utilized for various application areas, such as 5G smartphone applications and satellite communication. Full article

Incense burning is a significant source of indoor air pollution in many Asian regions. There is emerging evidence that maternal prenatal exposure to incense-burning smoke may be a risk factor for childhood obesity. We aimed to extend this new line of research by investigating the independent and joint effect of incense-burning smoke exposure, and children’s outdoor activity in early life, on preschoolers’ obesity. A total of 69,637 mother–child dyads were recruited from all kindergartens in the Longhua District of Shenzhen, China. Information on sociodemographic characteristics, maternal exposure to incense-burning smoke (IBS) during pregnancy, and frequency and duration of outdoor activity at the age of 1–3 years was collected by a self-administered questionnaire. In addition, the heights and weights of the children were measured by the research team. Logistic regression models and cross-over analyses were conducted to investigate the independent and combined effects of maternal exposure to incense-burning smoke during pregnancy and children’s early outdoor activity on obesity in preschoolers. We found that prenatal exposure to incense-burning smoke increased the risk of the presence of obesity in preschoolers’ (AOR = 1.13, 95% CI = 1.03–1.23). Additionally, lower frequencies (<3 times/week) or shorter durations (<60 min/time) of outdoor activity from the age of 1–3 years were significantly associated with the presence of obesity, with AORs of 1.24 (95% CI =1.18–1.32) and 1.11 (95% CI = 1.05–1.17), respectively. Furthermore, the cross-over analysis showed that prenatal exposure to IBS combined with a lower frequency of early outdoor activity (AOR = 1.47, 95% CI = 1.31–1.66) or a shorter duration of outdoor activity during ages of 1–3 years (AOR = 1.22, 95% CI = 1.07–1.39) increased the risk of obesity in preschoolers. Finally, additive interactions between prenatal exposure to IBS and postnatal outdoor activity on obesity were identified. Our study indicates that maternal exposure to incense-burning smoke during pregnancy and early lower postanal outdoor activity may independently and jointly increase the risk of obesity among preschoolers. Full article

Optimizing production processes to conserve resources and reduce waste has become crucial in pursuing sustainable manufacturing practices. The solid wood panel industry, marked by substantial raw materials and energy consumption, stands at the forefront of addressing this challenge. This research delves into production scheduling and equipment utilization inefficiencies, offering innovative solutions for the solid wood panel processing line aimed at achieving environmental sustainability and operational efficiency. The study is articulated through two main segments: (1) an exhaustive analysis and the development of a simulation system for the solid wood panel processing line, delineating all production elements and operational logic, furnished with a user-friendly simulation interface, and (2) a comprehensive evaluation and enhancement of various scheduling algorithms specific to the Flexible Job-Shop Scheduling Problem (FJSP) encountered in solid wood panel workshops. A significant leap forward is made with the introduction of the Adaptive Intelligent Optimization Genetic Algorithm (AIOGA), an evolved version of the standard Genetic Algorithm (GA) engineered for optimal scheduling within the solid wood panel processing line. AIOGA incorporates advanced features such as encoding strategy, population initialization, objective function setting, selection strategy, crossover operation, and mutation operation, demonstrating the methodological depth of the study. We applied AIOGA in a designed FJSP, and AIOGA substantially reduced the maximum completion time to 90 min. It evidenced an improvement of 39.60% over the conventional GA, enhancing the equilibrium of the equipment workload across the system. This research presents a multifaceted strategy to address the scheduling complications inherent in solid wood panel production and highlights the extensive applicability of adaptive intelligent optimization in diverse industrial settings. This study establishes a new paradigm in manufacturing optimization, underlining the valuable integration of sustainability and efficiency in production methodologies. Full article