Correlative Preference Transfer with Hierarchical Hypergraph Network for Multi-Domain Recommendation

Advanced recommender systems usually involve multiple domains (scenarios or categories) for various marketing strategies, and users interact with them to satisfy their diverse demands. The goal of multi-domain recommendation is to improve the recommendation performance of all domains simultaneously. Conventional graph neural network based methods usually deal with each domain separately, or train a shared model for serving all domains. The former fails to leverage users' cross-domain behaviors, making the behavior sparseness issue a great obstacle. The latter learns shared user representation with respect to all domains, which neglects users' domain-specific preferences. These shortcomings greatly limit their performance in multi-domain recommendation. To tackle the limitations, an appropriate way is to learn from multi-domain user feedbacks and obtain separate user representations to characterize their domain-specific preferences. In this paper we propose $\mathsf{H^3Trans}$, a hierarchical hypergraph network based correlative preference transfer framework for multi-domain recommendation. $\mathsf{H^3Trans}$ represents multi-domain feedbacks into a unified graph to help preference transfer via taking full advantage of users' multi-domain behaviors. We incorporate two hyperedge-based modules, namely dynamic item transfer module (Hyper-I) and adaptive user aggregation module (Hyper-U). Hyper-I extracts correlative information from multi-domain user-item feedbacks for eliminating domain discrepancy of item representations. Hyper-U aggregates users' scattered preferences in multiple domains and further exploits the high-order (not only pair-wise) connections among them to learn user representations. Experimental results on both public datasets and large-scale production datasets verify the superiority of $\mathsf{H^3Trans}$ for multi-domain recommendation.Comment: Work in progres

THE ISOKINETIC MUSCLE ASYMMETRY OF THE THIGH AT 1 YEAR AFTER ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION WAS SIGNIFICANTLY ASSOCIATED WITH GAIT ASYMMETRY

Objective: To study the correlation between muscle strength asymmetry and gait asymmetry in 1 year after （Anterior Cruciate Ligament Reconstruction， ACLR）. Methods: Twenty-five ACLR patients were enrolled in the Department of Sports Medicine, Peking University Third Hospital. Data of isokinetic muscle strength test one year after ACLR were collected. The concentric and eccentric strength of extensor and flexor muscles at 60°/s, 180°/s and 300°/s on the uninjured side and the injured side were measured respectively, and the peak value of muscle strength was analyzed. The three dimensional motion information and ground reaction force during gait were collected, and the peaks of three dimensional joint angle and moments during gait stance phase were calculated by inverse dynamics analysis. The paired-samples T test was used to analyze the difference of gait parameters and isokinetic muscle strength peaks. Spearman correlation analysis was used to study the correlation between bilateral asymmetry index of isokinetic muscle strength and gait asymmetry index. Results: One year after ACLR, the isokinetic muscle strength peaks of the flexor and extensor muscles on the injured side were significantly lower than those on the uninjured side【60°/s extensor concentric, the injured side: (1.22 ± 0.4)Nm·kg-1, uninjured side: (1.73 ± 0.42)Nm·kg-1, bilateral difference: (-0.5 ± 0.39)Nm·kg-1, P \u3c 0.01; 60°/s flexor concentric, injured side: (0.84 ± 0.19)Nm·kg-1, uninjured side: (1.05 ± 0.23)Nm·kg-1, bilateral difference: (-0.21 ± 0.14)Nm·kg-1, P \u3c 0.01】. Compared with the uninjured side, the injured side showed insufficient knee extension at the time of maximum knee extension during stance phase 【injured side: (5.25 ± 4.17) °, uninjured side: (2.24 ± 3.11) °, bilateral difference: (3.01 ± 2.44) °, P \u3c 0.01】, and the peak extension moment decreased significantly 【injured side: (0.1 ± 0.09) Nm·kg-1·m-1, (0.15 ± 0.07) Nm·kg-1·m-1, (-0.05 ± 0.06) Nm·kg-1·m-1, P \u3c 0.01】. One year after ACLR, the asymmetry of 180°/s isokinetic extensor concentric strength was significantly correlated with the asymmetry of peak flexion moment (R = 0.449, P = 0.024). The asymmetry of 60°/s isokinetic extensor concentric strength was significantly correlated with the asymmetry of peak internal rotation moment (R = 0.421, P = 0.036). One year after ACLR, asymmetries of 180°/s, 300°/s isokinetic extensor concentric strength and 60°/s isokinetic flexor eccentric strength were significantly correlated with peak asymmetries during stance phase. Conclusion: There is a significant correlation between isokinetic muscle strength asymmetry of knee and gait asymmetry. This study suggests that ACLR patients still need regular rehabilitation training to improve muscle strength and motor function 1 year after ACLR, so as to reduce the risk of reinjury and secondary injury

Hypersonic Vehicles Profile-Following Based on LQR Design Using Time-Varying Weighting Matrices

In the process of applying linear quadratic regulator (LQR) to solve aerial vehicle reentry reference trajectory guidance, to obtain better profile-following performance, the parameters of the aerial vehicle system can be used to calculate weighting matrices according to the Bryson principle. However, the traditional method is not applicable to various disturbances in hypersonic vehicles (HSV) which have particular dynamic characteristics. By calculating the weighting matrices constructed based on Bryson principle using time-varying parameters, a novel time-varying LQR design method is proposed to deal with the various disturbances in HSV reentry profile-following. Different from the previous approaches, the current states of the flight system are employed to calculate the parameters in weighting matrices. Simulation results are given to demonstrate that using the proposed approach in this chapter, performance of HSV profile-following can be improved significantly, and stronger robustness against different disturbances can be obtained

Fractional Calculus Guidance Algorithm in a Hypersonic Pursuit-Evasion Game

Aiming at intercepting a hypersonic weapon in a hypersonic pursuit-evasion game, this paper presents a fractional calculus guidance algorithm based on a nonlinear proportional and differential guidance law. First, under the premise of without increasing the complexity degree of the guidance system against a hypersonic manoeuvering target, the principle that the differential signal of the line-of-sight rate is more sensitive to the target manoeuver than the line-of-sight rate is employed as the guidelines to design the guidance law. A nonlinear proportional and differential guidance law (NPDG) is designed by using the differential derivative of the line-of-sight rate from a nonlinear tracking differentiator. By using the differential definition of fractional calculus, on the basis of the NPDG, a fractional calculus guidance law (FCG) is proposed. According to relative motions between the interceptor and target, the guidance system stability condition with the FCG is given and quantitative values are also proposed for the parameters of the FCG. Under different target manoeuver conditions and noisy conditions, the interception accuracy and robustness of these two guidance laws are analysed. Numerical experimental results demonstrate that the proposed guidance algorithms effectively reduce the miss distance against target manoeuvers. Compared with the NPDG, a stronger robustness of the FCG is shown under noisy condition

Who's Watching Me?: Exploring the Impact of Audience Familiarity on Player Performance, Experience, and Exertion in Virtual Reality Exergames

Familiarity with audiences plays a significant role in shaping individual performance and experience across various activities in everyday life. This study delves into the impact of familiarity with non-playable character (NPC) audiences on player performance and experience in virtual reality (VR) exergames. By manipulating of NPC appearance (face and body shape) and voice familiarity, we explored their effect on game performance, experience, and exertion. The findings reveal that familiar NPC audiences have a positive impact on performance, creating a more enjoyable gaming experience, and leading players to perceive less exertion. Moreover, individuals with higher levels of self-consciousness exhibit heightened sensitivity to the familiarity with NPC audiences. Our results shed light on the role of familiar NPC audiences in enhancing player experiences and provide insights for designing more engaging and personalized VR exergame environments.Comment: 10 pages, 5 figures, IEEE International Symposium on Mixed and Augmented Reality (ISMAR) 202

A three-dimensional insight into correlation between carrier lifetime and surface recombination velocity for nanowires

The performance of nanowire-based devices is predominantly affected by nonradiative recombination on their surfaces, or sidewalls, due to large surface-to-volume ratios. A common approach to quantitatively characterize surface recombination is to implement time-resolved photoluminescence to correlate surface recombination velocity with measured minority carrier lifetime by a conventional analytical equation. However, after using numerical simulations based on a three-dimensional (3D) transient model, we assert that the correlation between minority carrier lifetime and surface recombination velocity is dependent on a more complex combination of factors, including nanowire geometry, energy-band alignment, and spatial carrier diffusion in 3D. To demonstrate this assertion, we use three cases—GaAs nanowires, InGaAs nanowires, and InGaAs inserts embedded in GaAs nanowires—and numerically calculate the carrier lifetimes by varying the surface recombination velocities. Using this information, we then investigate the intrinsic carrier dynamics within those 3D structures. We argue that the conventional analytical approach to determining surface recombination in nanowires is of limited applicability, and that a comprehensive computation in 3D can provide more accurate analysis. Our study provides a solid theoretical foundation to further understand surface characteristics and carrier dynamics for 3D nanostructured materials

Diabetic retinopathy risk in patients with unhealthy lifestyle: A Mendelian randomization study

PurposeThis study aimed to investigate the causal association between unhealthy lifestyle factors and diabetic retinopathy (DR) risk and to determine better interventions targeting these modifiable unhealthy factors.DesignTwo-sample Mendelian randomization (MR) analysis was performed in this study. The inverse variance-weighted method was used as the primary method.MethodOur study included 687 single-nucleotide polymorphisms associated with unhealthy lifestyle factors as instrumental variables. Aggregated data on individual-level genetic information were obtained from the corresponding studies and consortia. A total of 292,622,3 cases and 739,241,18 variants from four large consortia (MRC Integrative Epidemiology Unit [MRC-IEU], Genetic Investigation of Anthropometric Traits [GIANT], GWAS & Sequencing Consortium of Alcohol and Nicotine Use [GSCAN], and Neale Lab) were included.ResultIn the MR analysis, a higher body mass index (BMI) (odds ratio [OR], 95% confidence interval [CI] = 1.42, 1.30–1.54; P < 0.001] and cigarettes per day (OR, 95% CI = 1.16, 1.05–1.28; P = 0.003) were genetically predicted to be causally associated with an increased risk of DR, while patients with higher hip circumference (HC) had a lower risk of DR (OR, 95% CI = 0.85, 0.76–0.95; P = 0.004). In the analysis of subtypes of DR, the results of BMI and HC were similar to those of DR, whereas cigarettes per day were only related to proliferative DR (PDR) (OR, 95% CI = 1.18, 1.04–1.33; P = 0.009). In the MR-PRESSO analysis, a higher waist-to-hip ratio (WHR) was a risk factor for DR and PDR (OR, 95% CI = 1.24, 1.02–1.50, P = 0.041; OR, 95% CI = 1.32, 1.01–1.73, P = 0.049) after removing the outliers. Furthermore, no pleiotropy was observed in these exposures.ConclusionOur findings suggest that higher BMI, WHR, and smoking are likely to be causal factors in the development of DR, whereas genetically higher HC is associated with a lower risk of DR, providing insights into a better understanding of the etiology and prevention of DR

Exploring time-resolved photoluminescence for nanowires using a three-dimensional computational transient model

Time-resolved photoluminescence (TRPL) has been implemented experimentally to measure the carrier lifetime of semiconductors for decades. For the characterization of nanowires, the rich information embedded in TRPL curves has not been fully interpreted and meaningfully mapped to the respective material properties. This is because their three-dimensional (3-D) geometries result in more complicated mechanisms of carrier recombination than those in thin films and analytical solutions cannot be found for those nanostructures. In this work, we extend the intrinsic power of TRPL by developing a full 3-D transient model, which accounts for different material properties and drift-diffusion, to simulate TRPL curves for nanowires. To show the capability of the model, we perform TRPL measurements on a set of GaAs nanowire arrays grown on silicon substrates and then fit the measured data by tuning various material properties, including carrier mobility, Shockley–Read–Hall recombination lifetime, and surface recombination velocity at the GaAs–Si heterointerface. From the resultant TRPL simulations, we numerically identify the lifetime characteristics of those material properties. In addition, we computationally map the spatial and temporal electron distributions in nanowire segments and reveal the underlying carrier dynamics. We believe this study provides a theoretical foundation for interpretation of TRPL measurements to unveil the complex carrier recombination mechanisms in 3-D nanostructured materials