Change In Tilt Angle Research Articles

Semi-analytical Monte Carlo simulation of underwater target echoes from a small UAV-based oceanic lidar

Small unmanned airborne oceanic lidars are becoming increasingly popular for ocean surveys. They typically weigh less than 10 kg and can be mounted on commonly used commercial drones, making them easier to use than traditional large oceanic lidars, which typically weigh up to 80 kg and can only be carried on manned aircraft. Unmanned airborne oceanic lidars typically fly at lower altitudes and use higher laser emission frequencies, making them suitable for detecting underwater targets. However, most of the existing LiDAR underwater echo simulation models are designed for flat terrain and assume that the target fills the LiDAR receiving field of view, and there are few studies on the echoes of suspended targets smaller than the field of view range. Therefore, we combined ray tracing and semi-analytical Monte Carlo to model the laser echo energy of the underwater target. The study investigated the energy change of the target echo in the direction of deviation from the laser outgoing direction, and the impact of absorption and scattering coefficients on it. The difference in echo energy between different fields of view for extended and non-extended targets and the effect of water quality on it were explored. The echo waveforms of the target under different tilt angles were simulated, and it was found that the target echo pattern will be tilted with the change of tilt angle and offset position.

Floating solar power loss due to motions induced by ocean waves: An experimental study

Whilst there is an interest in floating solar energy systems in coastal and offshore regions to utilise available sea space, they are subject to ocean waves that introduce constant momentum. Consequently, solar panels undergo periodic motions with the waves, causing a continuous change in tilt angle. The tilt angle variation is a sub-optimal process and leads to a loss of energy harnessing efficiency. To investigate this phenomenon, the present study innovatively installed a solar simulator on top of a wave tank. The solar simulator was used to generate high-strength light beams, under which, a floating solar unit was subject to periodic incident waves. Wave-induced motions to the solar system as well as the output power were measured. A systematic analysis of the results indicated that a floating solar unit can have significantly lower power output in waves, compared to its calm-water counterpart. An evident link was established between the wave-induced power loss and the wave-induced rotational movement of the panel. An empirical equation was derived which shows the power loss is predictable through the rotational amplitude. The results also highlight the importance of implementing wave attenuation technologies such as breakwaters to minimise wave-induced motions to floating solar systems. Overall, this research presents a novel experimental approach to assess the difference of floating solar power in ocean-wave versus calm-water scenarios, providing valuable insights for future solar projects on the ocean.

Effect of groove textures on wear of friction pair between groove side and scraper under different factor combinations

Three-body wear is the primary wear mechanism in friction pair between groove side and scraper. This study quantitatively investigates the effect of groove textures on three-body wear under different factor combinations through abrasive wear experiments. The results indicate that groove textures significantly reduce wear of samples. The wear reduction rate of sample reaches 41% under the optimal factor combination. Width, depth, and tilt angle of groove textures significantly influence wear loss. Among these factors, width exhibits a negative effect on the change of wear loss, while depth and tilt angle show positive effects. Additionally, there are interactive effects on the change of wear loss between width and depth, as well as width and tilt angle. The effect process of groove textures to three-body wear was qualitatively analyzed by discrete element method (DEM) simulation. Combined with wear morphologies, the wear-resistant mechanism of groove textures was explored. The results indicate that groove textures can mitigate the severity of three-body abrasive wear, reduce the contact area between particles and samples, alter particles movement and enhance wear resistance. Meanwhile, groove textures can serve as a guiding mechanism to modify particles movement and direction and transform the sliding motion of coal particles into rolling motion, converting the continuous “face-face” contact of three-body wear into intermittent “point-face” and “line-face” contacts. This study provides novel study ideas and theoretical foundations for wear-resistant designs in mining machinery and three-body wear equipment.

LPDi GAN: A License Plate De-Identification Method to Preserve Strong Data Utility.

License plate (LP) information is an important part of personal privacy, which is protected by law. However, in some publicly available transportation datasets, the LP areas in the images have not been processed. Other datasets have applied simple de-identification operations such as blurring and masking. Such crude operations will lead to a reduction in data utility. In this paper, we propose a method of LP de-identification based on a generative adversarial network (LPDi GAN) to transform an original image to a synthetic one with a generated LP. To maintain the original LP attributes, the background features are extracted from the background to generate LPs that are similar to the originals. The LP template and LP style are also fed into the network to obtain synthetic LPs with controllable characters and higher quality. The results show that LPDi GAN can perceive changes in environmental conditions and LP tilt angles, and control the LP characters through the LP templates. The perceptual similarity metric, Learned Perceptual Image Patch Similarity (LPIPS), reaches 0.25 while ensuring the effect of character recognition on de-identified images, demonstrating that LPDi GAN can achieve outstanding de-identification while preserving strong data utility.

Pathological mutations in the phospholamban cytoplasmic region affect its topology and dynamics modulating the extent of SERCA inhibition

Phospholamban (PLN) is a 52 amino acid regulin that allosterically modulates the activity of the sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA) in the heart muscle. In its unphosphorylated form, PLN binds SERCA within its transmembrane (TM) domains, approximately 20 Å away from the Ca2+ binding site, reducing SERCA's apparent Ca2+ affinity (pKCa) and decreasing cardiac contractility. During the enzymatic cycle, the inhibitory TM domain of PLN remains anchored to SERCA, whereas its cytoplasmic region transiently binds the ATPase's headpiece. Phosphorylation of PLN at Ser16 by protein kinase A increases the affinity of its cytoplasmic domain to SERCA, weakening the TM interactions with the ATPase, reversing its inhibitory function, and augmenting muscle contractility. How the structural changes caused by pathological mutations in the PLN cytoplasmic region are transmitted to its inhibitory TM domain is still unclear. Using solid-state NMR spectroscopy and activity assays, we analyzed the structural and functional effects of a series of mutations and their phosphorylated forms located in the PLN cytoplasmic region and linked to dilated cardiomyopathy. We found that these missense mutations affect the overall topology and dynamics of PLN and ultimately modulate its inhibitory potency. Also, the changes in the TM tilt angle and cytoplasmic dynamics of PLN caused by these mutations correlate well with the extent of SERCA inhibition. Our study unveils new molecular determinants for designing variants of PLN that outcompete endogenous PLN to regulate SERCA in a tunable manner.

The Naso-Orbito-Frontal (NOF) Complex In Facial Feminization Surgery

Background: With the increasing demand for facial feminization surgery, there is a growing need for reliable and reproducible techniques to enhance outcomes. Objective: This study aimed to evaluate the effectiveness of single-stage Naso-Orbito-Frontal (NOF) complex reshaping in facial feminization surgery. Effectiveness was gauged by CT scan assessments and an unvalidated patient satisfaction survey at 6 months post-operative. Methods: The study included 155 transfeminine patients undergoing surgery of the upper third of the face. Outcomes were compared in patients receiving either Orbito-Frontal (OF) surgery or combined Naso-Orbito-Frontal (NOF) surgery. A comparative analysis of pre- and postoperative standardized CT scan sections was performed, focusing on multiple anatomic angles in two dimensions. A self-administered satisfaction questionnaire based on six FACE-Q items was completed at 6 months. Results: Among the 155 patients, 65 underwent OF surgery, and 90 underwent NOF surgery. The follow-up period ranged from 6 to 36 months, with an average of 18 months. Significant changes in craniometric measurements were observed: in the OF group, average changes in nasofrontal, frontal tilt, and metopion angles were +12.3±0.2°, -8.5±2.2°, and +20.0±0.1° respectively (p<0.001); in the NOF group, same metrics were +28.5±0.3°, -9.3±2.4°, and +23.9±0.1° (p<0.001). The NOF group demonstrated higher overall satisfaction (Median: 4/5) compared to the OF group (Median: 3/5). No early complications were reported. Conclusion: The NOF complex surgery is an effective approach in gender-affirming surgery of the upper third of the face, yielding predictable results and higher patient satisfaction. Level of Evidence 3.

Accuracy of cup placement and pelvic motion in total hip arthroplasty in the lateral decubitus position using a new computed tomography-based navigation system with augmented reality technology.

This study aimed to investigate the accuracy of cup position and assess the changes in pelvic tilt during primary total hip arthroplasty (THA) in the lateral decubitus position using a new computed tomography (CT)-based navigation system with augmented reality (AR) technology. There were 37 cementless THAs performed using a CT-based navigation system with AR technology in the lateral decubitus position and 63 cementless THAs performed using manual implant techniques in the lateral decubitus position in this retrospective study. Postoperative cup radiographic inclination and anteversion were measured using postoperative CT, and the proportion of hips within Lewinnek's safe zone was analyzed and compared between the two groups. The mean absolute values of navigation error were assessed. Intraoperative pelvic tilt angles were also recorded using navigation system. The percentage of cups inside Lewinnek's safe zone was 100% in the navigation group and 35% in the control group (p < 0.001). The mean absolute values of navigation error in inclination and anteversion were 2.9° ± 2.1° and 3.3° ± 2.4°, respectively. The mean abduction angle of the pelvis was 5.1° ± 4.8° after placing the patients in the lateral decubitus position and 4.1° ± 6.0° after cup placement. The mean posterior tilt angle was 6.8° ± 5.1° after placing the patients in the lateral decubitus position and 9.3° ± 5.9° after cup placement. The mean internal rotation angle was 14.8° ± 7.4° after cup placement. There were no correlations between the navigation error in inclination or anteversion and the absolute values of changes of the pelvic tilt angle at any phase. Although progressive pelvic motion occurred in THA in the lateral decubitus position, especially during cup placement, the CT-based navigation system with AR technology improved cup placement accuracy.

Correlation analysis and clinical significance of changes in upper thoracic vertebra tilt and clavicle angle pre- and post-operation.

The imbalance of the lateral shoulder is reflected by the clavicle angle (CA) in radiology. It remains unclear how to achieve postoperative lateral shoulder balance (LSB) after spinal deformity correction surgery. A retrospective analysis was conducted on AIS patients who underwent surgery by the same spine surgeon at our hospital from 2016 to 2020. A total of 110 patients with spinal deformity were included in the study to verify the correlation between the T1-T5 tilt angle and CA before and after surgery, as well as the relation-ship between the change in T1-T5 tilt angle before and after surgery and the change in CA before and after surgery. By comparing the correlation coefficients, it was found that there may not be a direct relationship between the pre- and postoperative tilt angles of T1-5 and CA, but their changes were closely related to the changes in CA. The change in T1 tilt angle after orthopaedic surgery was significantly correlated with the change in CA, with a correlation coefficient of 0.976, indicating a close relationship between T1 and the clavicle. As the vertebrae moved down, the correlation gradually decreased. In summary, this study suggests that there is a close relationship between T1-T5 and the clavicle and that the change in T1 tilt angle after spinal scoliosis correction surgery is significantly correlated with CA, which decreases as the vertebra moves down.

The Anterior Modified San Diego Acetabuloplasty Does Not Increase Superior-Anterior Coverage in Patient-Specific 3D-Printed Models.

Patients with developmental dysplasia of the hip may require pelvic osteotomies to improve acetabular coverage. The purpose of this study was to compare the changes in acetabular version, tilt, and regional coverage angles following the San Diego acetabuloplasty (SDA), the modified San Diego acetabuloplasty (mSDA), and the Pemberton acetabuloplasty (PA). Fourteen patients with developmental dysplasia of the hip and computed tomography (CT) imaging were identified. From CT images, 2 identical pelvises were 3-dimensional-printed for each patient. Bone was printed with rigid material, and cartilage with flexible material. For each model pair, the SDA was performed on one and the PA was performed on the other. CT scans were obtained before and after acetabuloplasties. Next, the bone graft in the SDA model was moved anteriorly, representing the mSDA, and the model was rescanned. Acetabular version, tilt, and coverage angles (posterior, superior-posterior, superior, superior-anterior, and anterior) were calculated. Preoperative to postoperative differences were compared (repeated measures analysis of variance or Wilcoxon signed rank test). The significance was set to P <0.05. The mean age at CT was 5.8±1.2 years (range: 3.9 to 7.5y). All 3 procedures (SDA, mSDA, and PA) significantly increased acetabular tilt; P <0.045), with a similar change observed for all 3 ( P =0.868). PA was the only procedure to significantly decrease relative acetabular version (6.5±6.5 degrees, preoperative: 12.9±5.3 degrees; P =0.004). Both the SDA and mSDA procedures significantly increased coverage in the superior-posterior octant (SDA: 92.6±9.3 degrees, mSDA: 92.3±9.8 degrees, preoperative: 81.9±9.5 degrees; P <0.02), with a similar percent change among the 2 ( P =1.0). All 3 procedures significantly increased superior coverage ( P <0.04); the increase was similar among the 3 ( P =0.205). The PA was the only procedure to produce a significant increase in coverage in the superior-anterior octant (91.0±16.7 degrees, preoperative: 74.0±12.1 degrees; P =0.005) or the anterior octant (50.7±11.7 degrees, preoperative: 45.8±8.9 degrees; P =0.012). The SDA and mSDA procedures produced similar postoperative changes, primarily in the superior and superior-posterior acetabular octants. Placing the graft more anteriorly did not increase anterior coverage in the mSDA, and only the PA increased coverage in the superior and superior-anterior acetabular octants.

Effects of vibration-based biofeedback on multifidus muscle activity and pelvic tilt angle in subjects with hip flexion limitation.

Sedentary work may lead to low back pain. In particular, a slumped sitting position may exacerbate low back pain because of tissue damage caused by excessive lumbar flexion and posterior pelvic tilting. Subjects with low back pain may have excessive changes in the lumbopelvic posture and back muscle activity in the sitting position. The purpose of this study was to compare the effects of vibration-based biofeedback using a motion sensor belt and no biofeedback on multifidus (MF) muscle activity and pelvic tilt angle during typing. Thirty subjects with low back pain accompanied by hip flexion limitation (15 each in the biofeedback and non-biofeedback groups) were enrolled. Electromyography was used to investigate MF muscle activity before and after typing for 30 min. Pelvic tilt was measured after typing in a sitting position for 30 min. Independent t-tests were used to compare MF muscle activity, and pelvic and second sacrum tilt angles, between the biofeedback and non-biofeedback groups. After typing for 30 min, changes in MF muscle activity (11.45% and -7.19% for the biofeedback and nonbiofeedback groups, respectively) and pelvic and second sacrum tilt angles (3.15∘ and 4.12∘ for the biofeedback group and -11.05∘ and -18.16∘ for the non-biofeedback group, respectively) were significantly smaller in the biofeedback than non-biofeedback group (p< 0.05). Vibration-based biofeedback minimizes the reduction in MF muscle activity and changes in pelvic and second sacrum tilt angles during typing in individuals with low back pain accompanied by hip flexion limitation.

Study on transport process of 16 keV C&lt;sup&gt;– &lt;/sup&gt;ions in tapered glass capillary: Role of capillary tilt angles

&lt;sec&gt;The tapered glass capillaries have been widely used in physics, biology, materials. The features of ions transmitted through the insulating tapered glass capillary manifest themselves mainly in the interaction between positive ions and tapered glass capillary, However, the transmission process of negative ions in tapered glass capillary has been studied scarcely so far.&lt;/sec&gt;&lt;sec&gt;In the present study, we measure the properties of 16 keV C&lt;sup&gt;–&lt;/sup&gt; ions transmitted through the tapered glass capillary, such as the two-dimensional spectral distribution, the relative transmission rate, the centroid angle, the charge state purity and the full width at half maximum of the transmitted particles. As the tapered glass capillary tilt angle is equal to 0°, the transmitted particles are composed of three components, i.e. the core, the C&lt;sup&gt;–&lt;/sup&gt; of halo and the C&lt;sup&gt;0&lt;/sup&gt; of halo. As the tilt angle is 1°, the transmitted particles are composed of two components, i.e. C&lt;sup&gt;–&lt;/sup&gt; and C&lt;sup&gt;0&lt;/sup&gt;. As the tilt angle is &gt;1°, there is no core region, the transmitted particles are composed of two components, i.e. C&lt;sup&gt;–&lt;/sup&gt; and C&lt;sup&gt;0&lt;/sup&gt;. No matter how the tilt angle changes, the centroid angles of core are always along the direction of the incident ions, independent of the tilt angels. And the centroid angles of transmitted C&lt;sup&gt;–&lt;/sup&gt; and C&lt;sup&gt;0&lt;/sup&gt; are always along the direction of the capillary axis. The transmission processes of 16 keV C&lt;sup&gt;–&lt;/sup&gt; ions in tapered glass capillary with different tilting angles are analyzed qualitatively. When the tilting angle is small (0°–1°), the C&lt;sup&gt;–&lt;/sup&gt; ions are directly traveling straight through the back cone hole of tapered glass capillary, which are mainly composed of C&lt;sup&gt;–&lt;/sup&gt; ions. When the tilt angle is large (&gt;1°), the C&lt;sup&gt;–&lt;/sup&gt; ions cannot directly travel straight through the back cone hole of the tapered glass capillary, and the core region does not appear. Due to the guiding effect of the negative charges deposited on inner wall of tapered glass capillary, the transmitted C&lt;sup&gt;–&lt;/sup&gt; ions are located around the direction of the capillary axis. The tapered glass capillary has a focusing effect on the incident ions. This experiment covers the lack of the studies of low-energy negative ions transmitted through tapered capillary and helps to strengthen the understanding of the transmission process of low-energy ions transmitted through tapered capillary.&lt;/sec&gt;

Path‐Tracking Control of Tilting Quadrotor UAV Based on Variable Structure Sliding Mode Control Method

Tilting quadcopter unmanned aerial vehicles have the ability to perform vertical takeoff and landing, hover in the air, and cruise at high speeds, They can complete various flight tasks. Due to the special flight mode of tilting quadcopter unmanned aerial vehicles, in transition mode, as the tilt angle changes, the control process of the drone becomes more complex, and the difficulty of control also increases significantly. This article takes the tilting quadcopter drone as the research object and analyzes its overall layout and flight principles in various flight modes. Analyze using the Newton–Euler method and dynamically model three flight modes. The flight process is controlled using inner and outer loop control methods, and a sliding mode manifold control law for a tilting quadcopter unmanned aerial vehicle is designed using the hyperbolic tangent‐sliding mode control method. Finally, MATLAB/Simulink was used to simulate the path‐tracking process of the tilting quadcopter unmanned aerial vehicles, proving the stability of the controller.

Multifactorial analysis and experiments affecting the effect of fog droplet penetration in fruit tree canopies.

This study examines the impact of canopy density, side wind speed, nozzle tilt angle, and droplet size on droplet penetration during plant protection spraying operations. Experiments conducted in citrus orchards evaluated how side wind speed and nozzle tilt angle influence droplet penetration across various canopy densities. A Phase Doppler Analyzer (PDA) was used to assess droplet size variations under different nozzle tilt angles and side wind speeds, yielding a multiple linear regression equation (R2 = 0.866) that links nozzle tilt angle and side wind speed with droplet size. Results showed that droplet size decreases with increasing nozzle tilt angle at a constant crosswind speed. Further experiments investigated the effects of droplet size and canopy leaf area density on droplet penetration, involving three canopy leaf area densities, four wind speeds, and six nozzle tilt angles. Droplet deposition and canopy coverage were measured under various spraying parameters, with conventional operations (0° nozzle tilt and orthogonal wind speeds) serving as controls. The study found that adjusting nozzle tilt angle and wind speed enhances droplet penetration in different canopy structures. Optimal parameters varied with leaf area density (LAD): an 18° tilt angle and 3 m/s wind speed for a LAD of 5.94 m3/m3, a 45° tilt angle and 2 m/s wind speed for a LAD of 8.47 m2/m3, and a 36° tilt angle and 3 m/s wind speed for a LAD of 11.12 m2/m3. At 1 m/s, droplet deposition followed a downward parabolic trend with changes in nozzle tilt angle, whereas at 2 m/s, deposition followed an upward parabolic trend. At a side wind speed of 3 m/s, droplet deposition remained unchanged with nozzle tilt angle but decreased with increasing canopy density. Nonlinear regression analysis indicated that leaf area density had a greater impact on deposition differences than droplet size, with droplet penetration decreasing as leaf area density increased. This study provides a reference for enhancing fog droplet penetration techniques in plant protection operations, offering practical guidelines for optimizing spraying conditions and improving pesticide use efficiency in different canopy structures.

Constraints on the internal physics of neutron stars from the observational data of several young pulsars: The role of a power-law decaying dipole magnetic field

The observational data (e.g., the timing data and magnetic tilt angles χ) of young pulsars can be used to probe some critical issues about the internal physics of neutron stars (NSs), for instance, the number of precession cycles ξ and the internal magnetic field configuration (IMFC) of NSs. Evolution of the dipole magnetic field Bd of NSs may play an important role in determining the final results. In this work, a power-law form is adopted to describe the decay of Bd. In such a scenario, the IMFC and ξ of young pulsars with an ordinary Bd∼1012−1013 G and a steady braking index n are investigated. Since the tilt angle change rates χ˙ of pulsars with n<3 can be theoretically predicted, a test on the power-law decay model can thus be made by comparing the theoretical values to that obtained from observations. However, such a comparison can only be made on the Crab pulsar currently, and the results show that the power-law decay model is inconsistent with the Crab's observations. We suggest that rather than decay, the Crab's Bd should increase with time at a rate ∼12−14 G/s. A definite conclusion on the validity of the power-law decay model for pulsars with ordinary Bd may be given if χ˙ of other pulsars could be measured.

Posture-Induced Changes in Intraocular, Orbital, Cranial, Jugular Vein, and Arterial Pressures in a Porcine Model.

The purpose of this study was to determine posture-induced changes in arterial blood pressure (ABP), intraocular pressure (IOP), orbital pressure (Porb), intracranial pressure (ICP), and jugular vein pressure (JVP) at various tilt angles in an in vivo pig. Anesthetized and ventilated pigs (n = 8) were placed prone on a tiltable operating table. ABP, IOP, Porb, ICP, and JVP were monitored while the table was tilted at various angles between 15degrees head up tilt (HUT) and 25degrees head down tilt (HDT) either in stepwise changes (5 degrees per step) or continuously. The mean pressure was calculated from digitized pressure waveforms from each compartment. For stepwise changes in tilt angle the pressures were plotted as a function of tilt angle. For continuous tilt changes, the pressures were plotted as a function of time. In the case of stepwise changes, ABP remained relatively stable whilst IOP, Porb, ICP, and JVP demonstrated significant differences between most angles (typically P < 0.0001). The difference was greatest for IOP (P < 0.0001) where the average IOP increased from 13.1 ± 1.23mm Hg at 15degrees HUT to 46.3 ± 2.03mm Hg at 25 degrees HDT. The relationship between pressure and tilt angle was almost linear for ICP and JVP, and sigmoidal for IOP and Porb. Interestingly, the effect of changes in tilt angle occurred very rapidly, within a few seconds. Our results in a pig model demonstrate that changes in posture (tilt angle) induce rapid changes in IOP, Porb, ICP, and JVP, with IOP affected most severely.

The Mathematical Modeling and Performance of Sky Radiative Coolers

Sky radiative cooling is a kind of passive cooling technology that uses the “atmospheric window” to emit the object’s own heat to the low temperature of outer space; this technology has low energy consumption, no pollution, and other useful characteristics, so in recent years it has attracted widespread attention. The cooling effect of the sky radiative cooler is mainly affected by the constantly changing outdoor ambient temperature. In addition, the structure of the radiative cooler itself also means that its radiative cooling power undergoes obvious changes. Here, we utilized COMSOL simulation software to establish a numerical heat transfer model for radiative cooling, aimed at investigating the influencing factors on the sky radiative cooler and methods to enhance the structure of the radiative cooling. This study discusses outdoor ambient wind speed, the inlet flow rate of the cooler, installation angle of the cooler, and different cooler structures. Based on simulation results, it is observed that, for varying wind speeds, when the ambient radiation temperature is higher than the surface temperature of the cooler, a larger ambient wind speed leads to a poorer refrigeration effect. The maximum temperature difference in surface temperature at wind speeds of 0 m/s and 4 m/s is 0.59 °C. When the ambient temperature is lower than the surface temperature of the cooler, a smaller wind speed results in a greater net refrigeration power. The maximum temperature difference in this scenario is 0.32 °C. The net refrigeration power of the radiative cooler increases with an increase in water flow rate. As the water flow rate increases from 0 L/min to 5 L/min, the net refrigeration power increases from 25 W/m2 to 200 W/m2 and gradually stabilizes. Considering the radiative impact of the cooler on the surrounding environment, as the installation angle increases from 0° to 90°, the surface temperature of the cooler first increases and then decreases, reaching its highest temperature of 29.26 °C at 45°. The surface temperature of the cooler varies with the thickness of the air sandwich, increasing from 1 cm to 12 cm, and then decreasing. The lowest temperature of 23.4 °C is achieved at a thickness of 8 cm. The increase in the fin structure on the surface of the radiative cooler leads to a decrease in its refrigeration performance, and the difference between the inlet and outlet temperatures of the radiative cooler with a flat plate structure is always greater than that of the finned plate, and the difference in the average radiance is 23.52 W/m2. Finally, the energy-saving effect of the sky radiative cooling composite system is analyzed. Taking a typical small office building as an example, an energy consumption analysis model is set up, and the energy consumption of the composite system is simulated in four cities with different climates, using EnergyPlus software (version 8.6); the system’s power consumption is the largest in hot and humid climates. Compared with the traditional vapor-compression refrigeration system, the composite system reduces air conditioning power consumption by 25.7%, 32.5%, 37.1%, and 44.8% in Guangzhou, Shanghai, Jinan, and Shenyang, respectively. The main innovations of this paper include analyzing and studying the influence of the tilt angle change of the radiative plate on the refrigeration performance of the cooler and the relationship between the surrounding buildings, adding air sandwiches and ribs to the radiative cooler to analyze the influence of convective heat transfer on the refrigeration effect, which plays a guiding role in the design and research of the sky radiative cooler.

Association between Self-reported Sleep Quality and Single-task Gait in Young Adults: A Study Using Machine Learning.

Objective The objective of the present study was to find biomechanical correlates of single-task gait and self-reported sleep quality in a healthy, young population by replicating a recently published study. Materials and Methods Young adults ( n = 123) were recruited and were asked to complete the Pittsburgh Sleep Quality Inventory to assess sleep quality. Gait variables ( n = 53) were recorded using a wearable inertial measurement sensor system on an indoor track. The data were split into training and test sets and then different machine learning models were applied. A post-hoc analysis of covariance (ANCOVA) was used to find statistically significant differences in gait variables between good and poor sleepers. Results AdaBoost models reported the highest correlation coefficient (0.77), with Support-Vector classifiers reporting the highest accuracy (62%). The most important features associated with poor sleep quality related to pelvic tilt and gait initiation. This indicates that overall poor sleepers have decreased pelvic tilt angle changes, specifically when initiating gait coming out of turns (first step pelvic tilt angle) and demonstrate difficulty maintaining gait speed. Discussion The results of the present study indicate that when using traditional gait variables, single-task gait has poor accuracy prediction for subjective sleep quality in young adults. Although the associations in the study are not as strong as those previously reported, they do provide insight into how gait varies in individuals who report poor sleep hygiene. Future studies should use larger samples to determine whether single task-gait may help predict objective measures of sleep quality especially in a repeated measures or longitudinal or intervention framework.

Characteristics of Option and Denali Inferior Vena Cava Filters

To assess the characteristics of Option and Denali filters and to identify associations between these characteristics in each filter type. Consecutive patients who underwent Option or Denali filter placement between August 2019 and August 2022 were included in this retrospective study. A total of 119 patients (Option, n = 60; Denali, n = 59) were included. The retrieval rates were 45.0% for Option filters and 40.7% for Denali filters. The incidence of tilt at placement was higher for Option filters (76.7%) than for Denali filters (11.9%; P < 0.001). The tilt angle of Option filters at placement was correlated with the common iliac vein-inferior vena cava (CIV-IVC) angle. The incidence of tilt angle change after placement was higher for Option filters (74.1%) than for Denali filters (8.3%; P = 0.001). The IVC contraction rate after retrieval of Option is less than Denali (22.2% vs. 87.5%, P<0.001). The median fluoroscopy time during Option filter retrieval was longer than during Denali filter retrieval. The fluoroscopic time was related to tilt angle during retrieval of Option filters. Option filters are more likely than Denali filters to tilt at placement, and the tilt angle of Option filters is more prone to change after placement. The tilt angle at placement in Option filters is related to the CIV-IVC angle. Option filters require a longer fluoroscopic time during retrieval than Denali filters, and this increased fluoroscopic time is related to the tilt angle. Denali is more likely to cause IVC constriction after placement.

Analysis of Available Yawing Moment of an Autonomous Underwater Vehicle Model in Simulation Frame

Research endeavors on the design and control techniques of Autonomous Underwater Vehicles (AUVs) have been going on for a long time. In the present study, the yaw motion of a small submerged underwater vehicle is investigated and visualized as a direct result of changes in the rudder tilt angle and forward velocity. The numerical analysis is performed in ANSYS-Fluent software. The turbulent flow field has been modeled using Shear Stress Transport (SST) k-ω model. A grid independence test has been conducted to ensure the validity of the findings. The forces on the rudder and the available yaw moment have been obtained for different combinations of the AUV’s rudder tilt angle and forward velocity. The trend has intuitively been consistent and agreed with the basic concept of hydrodynamics

Clinical and Radiological Outcomes of a Comparative Study of Anterior Cervical Decompression and Fusion with Partial Pediculotomy, Partial Vertebrotomy (PPPV) Posterior Endoscopic Cervical Decompression (PECD) for Cervical Foraminal Pathology.

Background and Objectives: The purpose was to compaSre medium-term clinical and radiological outcomes of Partial Pediculotomy, Partial Vertebrotomy (PPPV) Posterior Endoscopic Cervical Decompression (PECD) surgery versus Anterior Cervical Discectomy and Fusion (ACDF) for patients with cervical disc herniations and foraminal pathologies. Materials and Methods: A prospective registry of patients who had undergone either PPPV PECD surgery or ACDF surgery for cervical disc herniation or foraminal pathologies under a single fellowship-trained spine surgeon was performed. The baseline characteristics and operative details including complications were recorded for all included patients. The clinical outcomes evaluated include VAS, MJOA, motor score, and NDI and MacNab's score. The radiological parameters in neutral-measured facet length, facet area, disc height, C2-C7 angle, neck tilt angle, T1 slope and thoracic inlet angle were also evaluated. Results: A total of 55 patients (29 PPPV PECD, 26 ACDF) were included, with mean follow-up periods of 21.9 and 32.3 months, respectively. Each cohort was noted to have a single case of surgical complication. Statistically significant changes of facet area (49.05 ± 14.50%) and facet length (52.71 ± 15.11%) were noted in the PPPV PECD group. At neutral alignment of the neck on a lateral X-ray, compared to ACDF, PPPV PECD had a statistically significant change in neck tilt angle (-11.68 ± 17.35°) and T1 slope angle (-11.69 ± 19.58°). Whilst both PPPV PECD and ACDF had significant improvements in VAS, MJOA and NDI postoperatively, PPPV PECD was found to be superior across all above scores at various follow-up timepoints compared to its ACDF counterparts. Conclusions: PPPV PECD surgery achieved a satisfactory radiological correction of neck alignment and significantly improved clinical outcomes at medium-term follow-up for our cohort of patients, highlighting its feasibility in treating patients with cervical disc herniations and foraminal pathologies.