Recent advances in 3D Gaussian Splatting (3DGS) have greatly improved 3D reconstruction. However, its substantial data size poses a significant challenge for transmission and storage. While many compression techniques have been proposed, they fail to efficiently adapt to fluctuating network bandwidth, leading to resource wastage. We address this issue from the perspective of size-aware compression, where we aim to compress 3DGS to a desired size by quickly searching for suitable hyperparameters. Through a measurement study, we identify key hyperparameters that affect the size - namely, the reserve ratio of Gaussians and bit-width settings for Gaussian attributes. Then, we formulate this hyperparameter optimization problem as a mixed-integer nonlinear programming (MINLP) problem, with the goal of maximizing visual quality while respecting the size budget constraint. To solve the MINLP, we decouple this problem into two parts: discretely sampling the reserve ratio and determining the bit-width settings using integer linear programming (ILP). To solve the ILP more quickly and accurately, we design a quality loss estimator and a calibrated size estimator, as well as implement a CUDA kernel. Extensive experiments on multiple 3DGS variants demonstrate that our method achieves state-of-the-art performance in post-training compression. Furthermore, our method can achieve comparable quality to leading training-required methods after fine-tuning.

Situation awareness (SA) is a crucial factor affecting flight safety for pilots, yet few studies have focused specifically on modeling SA for pilots, resulting in limited success. In this paper, we propose a novel multimodal deep learning approach to monitor pilots’ SA. The approach combines handcrafted and deep features obtained from eye movement and flight control data collected from 27 novice pilots across different training phases using a flight simulator. Ground truth SA measurements were obtained using the Situation Awareness Global Assessment Technique (SAGAT). The handcrafted features included 13 eye movements and 22 flight control features, while deep features were extracted from time-series of gaze positions using a deep extractor based on Transformer. By fusing the handcrafted features of eye movement and flight control, along with one deep feature of eye movement, we predicted the final SA level. Through leave-one-flight-out cross-validation, our model achieved a higher accuracy of 92.04%. The results indicate that the multimodal model outperforms the unimodal models, with the eye movement modality demonstrating superiority over the flight control modality in predicting SA. This suggests our method provides an objective means of predicting pilot’s SA and offers new insights for SA assessment in aviation and other fields. Overall, our multimodal deep learning approach holds promise for enhancing pilot training and flight safety by facilitating a more comprehensive understanding of pilots’ SA during critical flight scenarios.

Checking query equivalence is of great significance in database systems. Prior work in automated query equivalence checking sets the first steps in formally modeling and reasoning about query optimization rules, but only supports a limited number of query features. In this paper, we present Qed, a new framework for query equivalence checking based on bag semantics. Qed uses a new formalism called Q-expressions that models queries using different normal forms for efficient equivalence checking, and models features such as integrity constraints and NULLs in a principled way unlike prior work. Our formalism also allows us to define a new query fragment that encompasses many real-world queries with a complete equivalence checking algorithm, assuming a complete first-order theory solver. Empirically, Qed can verify 299 out of 444 query pairs extracted from the Calcite framework and 979 out of 1287 query pairs extracted from CockroachDB, which is more than 2× the number of cases proven by prior state-of-the-art solver.

In this paper, we propose a non-intrusive and nonrestrictive multimodal deep learning model for estimating the engagement levels of game streamers. We incorporate three modalities from the streamers' videos (facial, pixel, and audio information) to train the multimodal neural network. Additionally, we introduce a novel interpretation technique that directly calculates the contribution of each modality to the model's classification performance without the need to retrain single modality models. Experimental results demonstrate that our model achieves an accuracy of 77.2% on the test set, with the sound modality identified as a key modality for engagement estimation. By utilizing the proposed interpretation technique, we further analyze the modality contributions of the model in handling different categories and samples from various players. This enhances the model's interpretability and reveals its limitations, as well as future directions for improvement. The proposed approach and findings have potential applications in the fields of game streaming and audience analysis, as well as in domains related to multimodal learning and affective computing.

Souls-like games are one of the most popular and emerging genres in the contemporary gaming world. This study compared the behavioral characteristics, perspectives, and emotional expressions of players in Souls-like games from different cultural backgrounds, specifically examining the distinctions and commonalities among them. Natural language processing techniques were employed to analyze English, Chinese, and Russian reviews of 17 Souls-like games to investigate players' gaming experiences, including gameplay behaviors, game evaluations, and emotional experiences. The findings revealed significant disparities among players from different cultures in all three aspects of their engagement with Souls-like games. Specifically, these players exhibited significant culture-related variations in their behavioral characteristics towards Souls-like games. In terms of perspectives, English-speaking players tended to focus more on game optimization, whereas Chinese and Russian players paid greater attention to game combat design. Regarding emotional expressions, Chinese players were more prone to exhibit emotions of anger and disgust, while English and Russian players displayed a more neutral emotional stance. These cultural insights provide valuable information for game developers to better meet the needs and expectations of players from different cultural backgrounds. This study not only broadens our understanding of player behaviors and cultural influences but also lends robust support to cross-cultural gaming research.

Burst denoising aims to generate a clean image based on a sequence of noisy frames of the same scene captured in quick succession. However, relative motions inevitably happen between frames due to the movements of scenes or cameras, which would lead to blur and ghosting in the generated images. To address this issue, in this paper we propose a novel Efficient Burst Denoising Network (EBDNet) by integrating optical flow estimation with kernel prediction network in an end-to-end scenario. First, a lightweight Denoising Optical Flow Estimation (DOFE) module is presented for both burst feature and image alignment, which encourages to reduce the noise effect when making optical flow estimation. Building upon the aligned burst features and frames, a new fast Fourier convolution-enhanced kernel prediction module is introduced to merge the complementary information. It employs an encoder-decoder architecture with a well-designed feature enrichment block, which exploits the multi-level information from the encoder to boost the decoder features from both spatial and frequency domain views. Extensive experiments demonstrate that the proposed network achieves the best performance compared with state-of-the-art methods while maintaining reasonably low computing complexity.

Exploiting the relationships among data is a classical query optimization technique. As persistent data is increasingly being created and maintained programmatically, prior work that infers data relationships from data statistics misses an important opportunity. We present Coco, the first tool that identifies data relationships by analyzing database-backed applications. Once identified, Coco leverages the constraints to optimize the application's physical design and query execution. Instead of developing a fixed set of predefined rewriting rules, Coco employs an enumerate-test-verify technique to automatically exploit the discovered data constraints to improve query execution. Each resulting rewrite is provably equivalent to the original query. Using 14 real-world web applications, our experiments show that Coco can discover numerous data constraints from code analysis and improve real-world application performance significantly.

Internet services supported by large-scale distributed systems have become essential for our daily life. To ensure the stability and high quality of services, diverse metric data are constantly collected and managed in a time-series database to monitor the service status. However, when the number of metrics becomes massive, existing time-series databases are inefficient in handling high-rate data ingestion and queries hitting multiple metrics. Besides, they all lack the support of machine learning functions, which are crucial for sophisticated analysis of large-scale time series. In this paper, we present Lindorm TSDB, a distributed time-series database designed for handling monitoring metrics at scale. It sustains high write throughput and low query latency with massive active metrics. It also allows users to analyze data with anomaly detection and time series forecasting algorithms directly through SQL. Furthermore, Lindorm TSDB retains stable performance even during node scaling. We evaluate Lindorm TSDB under different data scales, and the results show that it outperforms two popular open-source time-series databases on both writing and query, while executing time-series machine learning tasks efficiently.

Driver identification has been popular in the field of driving behavior analysis, which has a broad range of applications in anti-thief, driving style recognition, insurance strategy, and fleet management. However, most studies to date have only researched driver identification without a robust verification stage. This paper addresses driver identification and verification through a deep learning (DL) approach using psychological behavioral data, i.e., vehicle control operation data and eye movement data collected from a driving simulator and an eye tracker, respectively. We design an architecture that analyzes the segmentation windows of three-second data to capture unique driving characteristics and then differentiate drivers on that basis. The proposed model includes a fully convolutional network (FCN) and a squeeze-and-excitation (SE) block. Experimental results were obtained from 24 human participants driving in 12 different scenarios. The proposed driver identification system achieves an accuracy of 99.60% out of 15 drivers. To tackle driver verification, we combine the proposed architecture and a Siamese neural network, and then map all behavioral data into two embedding layers for similarity computation. The identification system achieves significant performance with average precision of 96.91%, recall of 95.80%, F1 score of 96.29%, and accuracy of 96.39%, respectively. Importantly, we scale out the verification system to imposter detection and achieve an average verification accuracy of 90.91%. These results imply the invariable characteristics from human factors rather than other traditional resources, which provides a superior solution for driving behavior authentication systems.

Auxiliary information, such as reviews, have been widely adopted to improve collaborative filtering (CF) algorithms, e.g., to boost the accuracy and provide explanations. However, most of the existing methods cannot distinguish between co-appearance and causality when learning from the reviews, so that they may rely on spurious correlations rather than causal relations in the recommendation — leading to poor generalization performance and unconvincing explanations. In this paper, we propose a Recommendation via Review Rationalization (R3) method including 1) a rationale generator to extract rationales from reviews to alleviate the effects of spurious correlations; 2) a rationale predictor to predict user ratings on items only from generated rationales; and 3) a correlation predictor upon both rationales and correlational features to ensure conditional independence between spurious correlations and rating predictions given causal rationales. Extensive experiments on real-world datasets show that the proposed method can achieve better generalization performance than state-of-the-art CF methods and provide causal-aware explanations even when the test data distribution changes.