319 research outputs found
Horizon-unbiased Investment with Ambiguity
In the presence of ambiguity on the driving force of market randomness, we
consider the dynamic portfolio choice without any predetermined investment
horizon. The investment criteria is formulated as a robust forward performance
process, reflecting an investor's dynamic preference. We show that the market
risk premium and the utility risk premium jointly determine the investors'
trading direction and the worst-case scenarios of the risky asset's mean return
and volatility. The closed-form formulas for the optimal investment strategies
are given in the special settings of the CRRA preference
Exploring Target Representations for Masked Autoencoders
Masked autoencoders have become popular training paradigms for
self-supervised visual representation learning. These models randomly mask a
portion of the input and reconstruct the masked portion according to the target
representations. In this paper, we first show that a careful choice of the
target representation is unnecessary for learning good representations, since
different targets tend to derive similarly behaved models. Driven by this
observation, we propose a multi-stage masked distillation pipeline and use a
randomly initialized model as the teacher, enabling us to effectively train
high-capacity models without any efforts to carefully design target
representations. Interestingly, we further explore using teachers of larger
capacity, obtaining distilled students with remarkable transferring ability. On
different tasks of classification, transfer learning, object detection, and
semantic segmentation, the proposed method to perform masked knowledge
distillation with bootstrapped teachers (dBOT) outperforms previous
self-supervised methods by nontrivial margins. We hope our findings, as well as
the proposed method, could motivate people to rethink the roles of target
representations in pre-training masked autoencoders.The code and pre-trained
models are publicly available at https://github.com/liuxingbin/dbot.Comment: The first two authors contributed equall
A review for solar panel fire accident prevention in large-scale PV applications
Due to the wide applications of solar photovoltaic (PV) technology, safe operation and maintenance of the installed solar panels become more critical as there are potential menaces such as hot spot effects and DC arcs, which may cause fire accidents to the solar panels. In order to minimize the risks of fire accidents in large scale applications of solar panels, this review focuses on the latest techniques for reducing hot spot effects and DC arcs. The risk mitigation solutions mainly focus on two aspects: structure reconfiguration and faulty diagnosis algorithm. The first is to reduce the hot spot effect by adjusting the space between two PV modules in a PV array or relocate some PV modules. The second is to detect the DC arc fault before it causes fire. There are three types of arc detection techniques, including physical analysis, neural network analysis, and wavelet detection analysis. Through these detection methods, the faulty PV cells can be found in a timely manner thereby reducing the risk of PV fire. Based on the review, some precautions to prevent solar panel related fire accidents in large-scale solar PV plants that are located adjacent to residential and commercial areas
Evidence supported by Mendelian randomization: impact on inflammatory factors in knee osteoarthritis
BackgroundPrior investigations have indicated associations between Knee Osteoarthritis (KOA) and certain inflammatory cytokines, such as the interleukin series and tumor necrosis factor-alpha (TNFα). To further elaborate on these findings, our investigation utilizes Mendelian randomization to explore the causal relationships between KOA and 91 inflammatory cytokines.MethodsThis two-sample Mendelian randomization utilized genetic variations associated with KOA from a large, publicly accessible Genome-Wide Association Study (GWAS), comprising 2,227 cases and 454,121 controls of European descent. The genetic data for inflammatory cytokines were obtained from a GWAS summary involving 14,824 individuals of European ancestry. Causal relationships between exposures and outcomes were primarily investigated using the inverse variance weighted method. To enhance the robustness of the research results, other methods were combined to assist, such as weighted median, weighted model and so on. Multiple sensitivity analysis, including MR-Egger, MR-PRESSO and leave one out, was also carried out. These different analytical methods are used to enhance the validity and reliability of the final results.ResultsThe results of Mendelian randomization indicated that Adenosine Deaminase (ADA), Fibroblast Growth Factor 5(FGF5), and Hepatocyte growth factor (HFG) proteins are protective factors for KOA (IVWADA: OR = 0.862, 95% CI: 0.771–0.963, p = 0.008; IVWFGF5: OR = 0.850, 95% CI: 0.764–0.946, p = 0.003; IVWHFG: OR = 0.798, 95% CI: 0.642–0.991, p = 0.042), while Tumor necrosis factor (TNFα), Colony-stimulating factor 1(CSF1), and Tumor necrosis factor ligand superfamily member 12(TWEAK) proteins are risk factors for KOA. (IVWTNFα: OR = 1.319, 95% CI: 1.067–1.631, p = 0.011; IVWCSF1: OR = 1.389, 95% CI: 1.125–1.714, p = 0.002; IVWTWEAK: OR = 1.206, 95% CI: 1.016–1.431, p = 0.032).ConclusionThe six proteins identified in this study demonstrate a close association with the onset of KOA, offering valuable insights for future therapeutic interventions. These findings contribute to the growing understanding of KOA at the microscopic protein level, paving the way for potential targeted therapeutic approaches
X-ray emission for 424 MeV/u C ions impacting on selected targets
In inertial Confinement Fusion (ICF), X-ray
radiation drives the implosion requiring not only
sufficient conversion efficiency of the drive
energy to the X-ray but also the highly spatial
symmetry..
DiffusionFace: Towards a Comprehensive Dataset for Diffusion-Based Face Forgery Analysis
The rapid progress in deep learning has given rise to hyper-realistic facial
forgery methods, leading to concerns related to misinformation and security
risks. Existing face forgery datasets have limitations in generating
high-quality facial images and addressing the challenges posed by evolving
generative techniques. To combat this, we present DiffusionFace, the first
diffusion-based face forgery dataset, covering various forgery categories,
including unconditional and Text Guide facial image generation, Img2Img,
Inpaint, and Diffusion-based facial exchange algorithms. Our DiffusionFace
dataset stands out with its extensive collection of 11 diffusion models and the
high-quality of the generated images, providing essential metadata and a
real-world internet-sourced forgery facial image dataset for evaluation.
Additionally, we provide an in-depth analysis of the data and introduce
practical evaluation protocols to rigorously assess discriminative models'
effectiveness in detecting counterfeit facial images, aiming to enhance
security in facial image authentication processes. The dataset is available for
download at \url{https://github.com/Rapisurazurite/DiffFace}
Combinational effect of mutational bias and translational selection for translation efficiency in tomato (Solanum lycopersicum) cv. Micro-Tom
AbstractWe conducted a comprehensive analysis of codon usage bias (CUB) based on the available non-redundant full-length cDNA (nrFLcDNA) and expressed sequence tags (ESTs) data of cultivar Micro-Tom and evaluated the associations of observed CUB and measurements of transcriptional and translational effectiveness. The analysis presented in our study suggests a correlation, which is negative but highly correlated between Axis 1 and GC3s (r=−0.827, P<0.01), indicating that mutational bias has a significant and dominant repressive role to the choices of GC3. We also observed a strong positive correlation between codon adaptation index (CAI) and translational adaptation index (tAIg) (0.407, P<0.01), which demonstrates the facilitation of efficient translation by the optimal codon usage patterns of the highly expressed genes. We believe that the complete set of optimal codon usage patterns detected in this study will serve as a model to enhance the transgenesis in the studied cultivar of Solanum lycopersicum
PHOTOMETRIC OBSERVATION OF 3024 HAINAN, 3920 AUBIGNAN, AND 5951 ALICEMONET
Three minor planets were measured photometrically between 2012 September 4 and 21 using the SARA (Southeastern Association for Research in Astronomy) South telescope, located in Cerro Tololo Inter-American Observatory. The following synodic periods were found: 3024 Hainan, P = 11.785 ± 0.005 h; 3920 Aubignan, P = 4.4762 ± 0.0005 h; and 5951 Alicemonet, P = 3.8871 ± 0.0005 h
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