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Addressing the challenges that unmanned underwater vehicles (UUVs) face in path planning, including complex constraints, unstable optimization algorithm performance, and unsmooth paths, this paper proposes a path planning method using an improved particle swarm optimization (PSO) algorithm. Firstly, the function simulation method is employed to construct the underwater terrain and obstacle environment. Secondly, in terms of designing optimization objectives, the paper adds to the conventional minimization of path length, optimizing changes in the unmanned underwater vehicle's attitude angle and the uniform distribution of steering node positions, making it more adaptable to actual conditions, all with a focus on reducing energy consumption. Following this, the article analyzes the effect of inertia weight in the PSO algorithm on algorithm performance, introducing improvement measures to enhance the algorithm's optimization performance. Lastly, the calculated initial path is smoothed via B-spline curves to derive the final trajectory for robot motion planning. The simulation results demonstrate that compared to traditional ant colony optimization and standard PSO algorithms, the devised path optimization method reduces overall energy consumption by 56.6% and 19.3%, respectively, presenting superior problem-solving ability and convergence performance.

Owing to the inherent complexities of underwater environments, coupled with restrictive observational angles, the precise operation of an underwater manipulator during autonomous tasks is a sizable undertaking. To tackle this issue, this paper proposes a method for autonomous control of an underwater manipulator, leveraging the robust adaptive capacity of reinforcement learning algorithms. Initially, a reinforced learning approach is developed using proximal policy optimization (PPO) intertwined with an actor-critic (AC) algorithm to formulate the autonomous control strategy. Subsequently, an artificial potential field-based reward shaping method is introduced to address the sparse reward predicament apparent throughout the training process. Lastly, a simulation experiment validates the devised control strategy trained using the aforementioned procedures. The verification results illustrate that the strategy competently converges and commands the autonomous movement of the underwater manipulator towards intended targets. It allows for quick, fluid transitions and provides a smooth, stable track for the end effector.

Purpose: To examine the consistency of findings between two studies examining the impact of sport education on Chinese physical education preservice teachers' content knowledge and performance of volleyball and basketball. Methods: One hundred and six preservice teachers' from a university in central China participated in six semester-long courses of basketball taught using either a Multi-Activity or Sport Education model of instruction. Pre- and postcourse measures of game performance were recorded for common content knowledge and specialized content knowledge. Results: After controlling for preintervention scores, statistically significant differences favoring Sport Education were found for common content knowledge as well as specialized content knowledge. Students in Sport Education had 62 times higher odds of reaching the specialized content knowledge benchmark depth for acceptable content development. Conclusion: These findings provide support for the idea that the accountability mechanisms specific to Sport Education, together with the tasks related to designing team training plans, serve to promote students' ability to design and sequence tasks based on their team's needs.

Purpose: The purpose of this study was to examine the effects of Play Practice instruction on the badminton content knowledge and skill of a cohort of Chinese physical education majors. Method: Seventy-two second-year students participated in semester-long courses following either the principles of Play Practice or skill-focused instruction. A control/comparison group experimental design with pre- and postmeasures was used in this study. Separate analyses of variance with repeated measures (Time × Group) were conducted to examine the effects of Play Practice and skill-focused instruction for each of four dependent variables: (a) forehand clear, (b) tactical understanding, (c) game performance, and (d) specialized content knowledge. Results: Students from both conditions made significant improvements in all four variables across the semester. However, students in the Play Practice condition showed significantly greater gains in tactical understanding, game performance, and specialized content knowledge. In particular, while 75% of students who experienced Play Practice reached the 3.0 benchmark score for adequate specialized content knowledge, only 8% of students in skill-focused instruction reached this standard.

Purpose: The purpose of this study was to examine the effects of Play Practice (PP) instruction on badminton performance in college students. Method: A total of 66 students from the United States and China participated in units following either the principles of PP or skill-focused instruction. A nonequivalent control/comparison group experimental design with premeasure and postmeasure was used in this study. Separate analyses of variance with repeated measures (Time × Group) were conducted to examine the effects of PP and skill-focused instruction for each of the four dependent variables: (1) forehand clear; (2) wall volley; (3) game performance; and (4) tactical understanding. Results: Both PP and skill-focused instruction conditions were effective in improving participants' skills from pretest to posttest. However, PP was also effective in improving participants' game performance. Conclusion: PP effectively developed both fundamental skills and tactical aspects of badminton without diminishing the transfer effect from practice to games.

This study examined the impact of including a formal requirement of achieving predetermined energy expenditures as part of students' participation grades during a Sport Education-based college physical education class. Calorie consumption was measured using the Heart Zones Blink 3.0 sensor, and the percentage of students who reached the lesson target was calculated across a 15-week semester. The instructor kept a weekly journal and students participated in interviews at mid and end of term. Results showed that the average calorie consumption across the semester well exceeded the daily targets, while the percentage of students who reached the daily challenge cutoff ranged from 77% to 100% (average = 87%). Analysis of the journal entries and interviews resulted in the generation of four themes: students' commitment to reaching the activity targets, group-based strategies for achieving physical activity targets, activity consequences of officiating roles, and activity challenges problematized skill development for some.

The goal of China's new guidelines for physical education within universities is to promote greater levels of active engagement and an emphasis on the development and cultivation of students' individual abilities. This study follows an engagement perspective to examine the responses of stakeholders to the incorporation of the essential elements of Sport Education within an elective physical education basketball sports club. Participants were 152 students who after five weeks of term could elect to participate in a Sport Education season or continue to practice individually. Dependent measures included club attendance, students' perceptions of competence, knowledge/understanding and enjoyment of basketball. In addition, the teacher kept a reflective log across the season and participated in a formal interview at season's end. The students who participated in the Sport Education option had significantly greater attendance than their skill practice classmates. Further, they reported significant improvements in competence, as well as a higher level of enjoyment over their previous college physical education experience. These results demonstrate that highly autonomous format of the basketball club is conducive in supporting students' engagement in physical education.

A wideband bandpass filter (BPF) using capacitor-loaded coupled lines is proposed with super-compact circuit size and very simple structure. By loading three lumped capacitors in parallel to three same pairs of coupled lines, three transmission poles and four transmission zeros can be achieved and they can be calculated by input admittance derivation. To verify the design, a wideband BPF prototype with center frequency at 1.34 GHz is fabricated, whose measured 3-dB fractional bandwidth is 98.5 % (0.68–2 GHz), in-band insertion loss is less than 0.5 dB, return loss is greater than 17.5 dB, and circuit size is only 0.24 λg × 0.02 λg (λg: guided wavelength at the center frequency). [ABSTRACT FROM AUTHOR]

A novel AgCuTi brazing foil with a unique microstructure was developed, which could achieve strong vacuum brazing of Ti6Al4V (TC4) and sapphire. The brazing foil was composed of Ag solid solution (Ag(s,s)), Cu solid solution (Cu(s,s)), and layered Ti-rich phases, and had a low liquidus temperature of 790 °C and a narrow melting range of 16 °C, facilitating the defect-free joining of TC4 and sapphire. The sapphire/TC4 joint fabricated by using this novel AgCuTi brazing foil exhibited an outstanding average shear strength of up to 132.2 MPa, which was the highest value ever reported. The sapphire/TC4 joint had a characteristic structure, featuring a brazing seam reinforced by TiCu particles and a thin Ti3(Cu,Al)3O reaction layer of about 1.3 μm. The fracture mechanism of the sapphire/TC4 joint was revealed. The crack originated at the brazing seam with TiCu particles, then propagated through the Ti3(Cu,Al)3O reaction layer, detached the reaction layer from the sapphire, and finally penetrated into the sapphire. This study offers valuable insights into the design of active brazing alloys and reliable metal–ceramic bonding. [ABSTRACT FROM AUTHOR]

Histone acetylation is an important epigenetic mechanism that has been shown to play a role in diapause regulation. To explore the physiological and molecular mechanisms of histone deacetylase in the diapause process, LC-MS/MS analysis was used to perform TMT proteomic and metabolomic analysis on non-diapause (ND), pre-diapause (PreD), diapause (D), cold treatment (CT), and post-diapause (RD) stages of the meadow moth. A total of 5367 proteins were identified by proteomics, including 1179 differentially expressed proteins. We found 975 (602 up-regulated and 373 down-regulated), 997 (608 up-regulated and 389 down-regulated), 1119 (726 up-regulated and 393 down-regulated), 1179 (630 up-regulated and 549 down-regulated), 94 (51 up-regulated and 43 down-regulated), 111 (63 up-regulated and 48 down-regulated), 533 (243 up-regulated and 290 down-regulated), 58 (31 up-regulated and 27 down-regulated), and 516 (228 up-regulated and 288 down-regulated) proteins in ND and PreD, ND and D, ND and CT, ND and RD, PreD and D, PreD and CT, PreD and RD, D and CT, D and RD, and CT and RD stages, respectively. A total of 1255 differentially expressed metabolites were annotated by metabolomics. Through KEGG analysis and time series analysis of differentially expressed metabolites, we found that phospholipids were annotated in significantly different modules, demonstrating their important role in the diapause process of the meadow moth. Using phospholipids as an indicator for weighted gene co-expression network analysis, we analyzed the most relevant differentially expressed proteins in the module and found that ribosomal 40s and 60s subunits were the most relevant proteins for diapause. Because there have been studies that have shown that histone deacetylase is associated with the diapause of meadow moths, we believe that histone deacetylase regulates the 40s and 60s subunits of ribosomes, which in turn affects the diapause of meadow moths. This finding expands our understanding of the regulation of meadow moth diapause and provides new insights into its control mechanism. [ABSTRACT FROM AUTHOR]

Nowadays, amine containing electrode interface material destroy the non‐fullerene acceptor becomes a hard nut to crack for organic solar cells. Developing water‐soluble interface material which is no chemical reaction with non‐fullerene acceptor is an important research theme. Here, we report two bi‐triangular pyramidal electronic configuration organic‐phosphonium bromides as non‐amine cathode interfacial layer for fabricating high‐efficiency stable organic solar cells. The power conversion efficiency (PCE) of inverted device structure with PBDB‐T/ITIC as active layer is up to 11.58 % which is great larger than control device PCE (9.35 %). Same device structure with PM6/Y6 as active layer, the PCE is up to 15.26 % and also is dramatically higher than the referred device PCE 14.36 %. Meanwhile, the devices show greatly improved stability by organic‐phosphonium bromide interlayer. [ABSTRACT FROM AUTHOR]

Mallards (Anas platyrhynchos) exhibit exceptional locomotive abilities in diverse terrains, such as beaches, swamps, and tidal flats. This capability is primarily attributed to their unique webbed toe structure and cooperative locomotion posture of their feet. Therefore, this study aims to further delve into the active adaptive strategies of mallard feet in response to diverse external environmental conditions. Six adult male mallards were selected for this research. Their locomotion on sandy surfaces with differing wetness levels and varying degrees of compaction were captured using a high-speed camera, and analysis of instantaneous and continuous changes in the primary joint angles of the mallards' feet, including the toe-webbed opening and closing angles, the tarsometatarsal-phalangeal joint (TMTPJ), and the intertarsal joint (ITJ). It was found that on loose sandy surfaces, increasing wetness expanded the ground contact area of the mallards' feet. This led to greater flexion at the TMTPJ joint during mid-stance, accompanied by decreased flexion of the ITJ during touch-down and mid-stance. Conversely, on compacted sand, increasing wetness resulted in a reduced foot effect area and lessened ITJ flexion at both touch-down and mid-stance. Furthermore, on looser sand, the ground contact area of the mallards' feet decreased, with an increase in ITJ buckling at touch-down. During the swing phase, sand wetness and compactness effected minimally on the feet of the mallards. On dry and loose sand ground, mallards will contract their second and fourth toes with webbing upon ground contact, covering and compacting the sand beneath, while increasing ITJ flexion to mitigate sinking. This adaptation reduces the energy expended on sand and enhances body stability. In wet and compacted sand conditions, mallards expand their second and fourth toes upon ground contact and reduce ITJ flexion. Therefore, this coordinated foot and ITJ locomotion offers mallards a natural advantage when moving on various environmental media. [ABSTRACT FROM AUTHOR]