41 research outputs found
LayerDiffusion: Layered Controlled Image Editing with Diffusion Models
Text-guided image editing has recently experienced rapid development.
However, simultaneously performing multiple editing actions on a single image,
such as background replacement and specific subject attribute changes, while
maintaining consistency between the subject and the background remains
challenging. In this paper, we propose LayerDiffusion, a semantic-based layered
controlled image editing method. Our method enables non-rigid editing and
attribute modification of specific subjects while preserving their unique
characteristics and seamlessly integrating them into new backgrounds. We
leverage a large-scale text-to-image model and employ a layered controlled
optimization strategy combined with layered diffusion training. During the
diffusion process, an iterative guidance strategy is used to generate a final
image that aligns with the textual description. Experimental results
demonstrate the effectiveness of our method in generating highly coherent
images that closely align with the given textual description. The edited images
maintain a high similarity to the features of the input image and surpass the
performance of current leading image editing methods. LayerDiffusion opens up
new possibilities for controllable image editing.Comment: 17 pages, 14 figure
Efficient Privacy-Preserving Machine Learning with Lightweight Trusted Hardware
In this paper, we propose a new secure machine learning inference platform
assisted by a small dedicated security processor, which will be easier to
protect and deploy compared to today's TEEs integrated into high-performance
processors. Our platform provides three main advantages over the
state-of-the-art:
(i) We achieve significant performance improvements compared to
state-of-the-art distributed Privacy-Preserving Machine Learning (PPML)
protocols, with only a small security processor that is comparable to a
discrete security chip such as the Trusted Platform Module (TPM) or on-chip
security subsystems in SoCs similar to the Apple enclave processor. In the
semi-honest setting with WAN/GPU, our scheme is 4X-63X faster than Falcon
(PoPETs'21) and AriaNN (PoPETs'22) and 3.8X-12X more communication efficient.
We achieve even higher performance improvements in the malicious setting.
(ii) Our platform guarantees security with abort against malicious
adversaries under honest majority assumption.
(iii) Our technique is not limited by the size of secure memory in a TEE and
can support high-capacity modern neural networks like ResNet18 and Transformer.
While previous work investigated the use of high-performance TEEs in PPML,
this work represents the first to show that even tiny secure hardware with
really limited performance can be leveraged to significantly speed-up
distributed PPML protocols if the protocol can be carefully designed for
lightweight trusted hardware.Comment: IEEE S&P'24 submitte
Efficient Dynamic Proof of Retrievability for Cold Storage
Storage-as-a-service (STaaS) permits the client to outsource her data to the cloud thereby, reducing data management and maintenance costs. However, STaaS also brings significant data integrity and soundness concerns since the storage provider might not keep the client data intact and retrievable all the time (e.g., cost saving via deletions). Proof of Retrievability (PoR) can validate the integrity and retrievability of remote data effectively. This technique can be useful for regular audits to monitor data compromises, as well as to comply with standard data regulations. In particular, cold storage applications (e.g., MS Azure, Amazon Glacier) require regular and frequent audits but with less frequent data modification. Yet, despite their merits, existing PoR techniques generally focus on other metrics (e.g., low storage, fast update, metadata privacy) but not audit efficiency (e.g., low audit time, small proof size). Hence, there is a need to develop new PoR techniques that achieve efficient data audit while preserving update and retrieval performance.
In this paper, we propose Porla, a new PoR framework that permits efficient data audit, update, and retrieval functionalities simultaneously. Porla permits data audit in both private and public settings, each of which features asymptotically (and concretely) smaller audit-proof size and lower audit time than all the prior works while retaining the same asymptotic data update overhead. Porla achieves all these properties by composing erasure codes with verifiable computation techniques which, to our knowledge, is a new approach to PoR design. We address several challenges that arise in such a composition by creating a new homomorphic authenticated commitment scheme, which can be of independent interest. We fully implemented Porla and evaluated its performance on commodity cloud (i.e., Amazon EC2) under various settings. Experimental results demonstrated that Porla achieves two to four orders of magnitude smaller audit proof size with 4× – 1,800× lower audit time than all prior schemes in both private and public audit settings at the cost of only 2× – 3× slower update
One-Pixel Attack for Continuous-Variable Quantum Key Distribution Systems
Deep neural networks (DNNs) have been employed in continuous-variable quantum key distribution (CV-QKD) systems as attacking detection portions of defense countermeasures. However, the vulnerability of DNNs leaves security loopholes for hacking attacks, for example, adversarial attacks. In this paper, we propose to implement the one-pixel attack in CV-QKD attack detection networks and accomplish the misclassification on a minimum perturbation. This approach is based on the differential evolution, which makes our attack algorithm fool multiple DNNs with the minimal inner information of target networks. The simulation and experimental results show that, in four different CV-QKD detection networks, 52.8%, 26.4%, 21.2%, and 23.8% of the input data can be perturbed to another class by modifying just one feature, the same as one pixel for an image. We carry out this success rate in the context of the original accuracy reaching up to nearly 99% on average. Further, by enlarging the number of perturbed features, the success rate can be raised to a satisfactory higher level of about 80%. According to our experimental results, most of the CV-QKD detection networks can be deceived by launching one-pixel attacks
One-Pixel Attack for Continuous-Variable Quantum Key Distribution Systems
Deep neural networks (DNNs) have been employed in continuous-variable quantum key distribution (CV-QKD) systems as attacking detection portions of defense countermeasures. However, the vulnerability of DNNs leaves security loopholes for hacking attacks, for example, adversarial attacks. In this paper, we propose to implement the one-pixel attack in CV-QKD attack detection networks and accomplish the misclassification on a minimum perturbation. This approach is based on the differential evolution, which makes our attack algorithm fool multiple DNNs with the minimal inner information of target networks. The simulation and experimental results show that, in four different CV-QKD detection networks, 52.8%, 26.4%, 21.2%, and 23.8% of the input data can be perturbed to another class by modifying just one feature, the same as one pixel for an image. We carry out this success rate in the context of the original accuracy reaching up to nearly 99% on average. Further, by enlarging the number of perturbed features, the success rate can be raised to a satisfactory higher level of about 80%. According to our experimental results, most of the CV-QKD detection networks can be deceived by launching one-pixel attacks
Ingestion of GNSS-Derived ZTD and PWV for Spatial Interpolation of PM2.5 Concentration in Central and Southern China
With the increasing application of global navigation satellite system (GNSS) technology in the field of meteorology, satellite-derived zenith tropospheric delay (ZTD) and precipitable water vapor (PWV) data have been used to explore the spatial coverage pattern of PM2.5 concentrations. In this study, the PM2.5 concentration data obtained from 340 PM2.5 ground stations in south-central China were used to analyze the variation patterns of PM2.5 in south-central China at different time periods, and six PM2.5 interpolation models were developed in the region. The spatial and temporal PM2.5 variation patterns in central and southern China were analyzed from the perspectives of time series variations and spatial distribution characteristics, and six types of interpolation models were established in central and southern China. (1) Through correlation analysis, and exploratory regression and geographical detector methods, the correlation analysis of PM2.5-related variables showed that the GNSS-derived PWV and ZTD were negatively correlated with PM2.5, and that their significances and contributions to the spatial analysis were good. (2) Three types of suitable variable combinations were selected for modeling through a collinearity diagnosis, and six types of models (geographically weighted regression (GWR), geographically weighted regression kriging (GWRK), geographically weighted regression—empirical bayesian kriging (GWR-EBK), multiscale geographically weighted regression (MGWR), multiscale geographically weighted regression kriging (MGWRK), and multiscale geographically weighted regression—empirical bayesian kriging (MGWR-EBK)) were constructed. The overall R2 of the GWR-EBK model construction was the best (annual: 0.962, winter: 0.966, spring: 0.926, summer: 0.873, and autumn: 0.908), and the interpolation accuracy of the GWR-EBK model constructed by inputting ZTD was the best overall, with an average RMSE of 3.22 μg/m3 recorded, while the GWR-EBK model constructed by inputting PWV had the highest interpolation accuracy in winter, with an RMSE of 4.5 μg/m3 recorded; these values were 2.17% and 4.26% higher than the RMSE values of the other two types of models (ZTD and temperature) in winter, respectively. (3) The introduction of the empirical Bayesian kriging method to interpolate the residuals of the models (GWR and MGWR) and to then correct the original interpolation results of the models was the most effective, and the accuracy improvement percentage was better than that of the ordinary kriging method. The average improvement ratios of the GWRK and GWR-EBK models compared with that of the GWR model were 5.04% and 14.74%, respectively, and the average improvement ratios of the MGWRK and MGWR-EBK models compared with that of the MGWR model were 2.79% and 12.66%, respectively. (4) Elevation intervals and provinces were classified, and the influence of the elevation and the spatial distribution of the plane on the accuracy of the PM2.5 regional model was discussed. The experiments showed that the accuracy of the constructed regional model decreased as the elevation increased. The accuracies of the models in representing Henan, Hubei and Hunan provinces were lower than those of the models in representing Guangdong and Guangxi provinces
Evaluation of fast fluid dynamics with different solving schemes on scalar transport equation for predicting indoor contaminant concentration
Predicting the transport of indoor pollution can assist designer to optimize ventilation mode of room. However, the high computational cost restricts the wide implementation of computational fluid dynamics (CFD) technique to predict indoor contaminant concentration. This study evaluated three potential numerical methods with scalar transport equation to resolve this dilemma which were combine fast fluid dynamics (FFD) and different solving schemes on scalar transport equation. To test the performance of three potential numerical methods, the conventional PISO algorithm was also employed to compare. A threedimensional ventilation case with experimental data of indoor CO2 concentration was adopted. The results show that the FFD with iterative scheme of scalar transport equation could predicting indoor CO2 concentration efficiently. The numerical method with semi-Lagrangian method and iterative scheme for predicting indoor air contaminant concentration could obtain satisfactory results at large time step size
The research on identification and spatial pattern of urban mixed land-use: A case study of Chengdu
In the context of urban quality enhancement, resilience focus, and the promotion of human-centered urbanization, a well-structured mixed land-use layout plays a pivotal role in intensifying conservation land use, enhancing land use efficiency, and improving residents' living environments. The existing research on measuring mixed land parcels is hampered by a lack of area and category data for POI point data, and some methods neglect the variations in function quantities. This paper establishes an optimal calculation model by incorporating the weighted optimization of POI data, introduces the concept of land gravity to supplement the entropy method, and computes the distribution of mixed land-use patterns. This paper analyzes both the spatial patterns of mixed land-use in urban areas and the potential laws governing the combination of internal functions. The results demonstrate that mixed-use parcels exhibit a spatial pattern resembling a “1 + n” pole-axis structure and a “T-type” development trend. Regarding the internal function combination, mixed-use parcels are generally found to include commercial and transportation functions. The paper provides suggestions and discussions on optimizing the layout and function structure of mixed land-use, offering a reference for current urban mixed land-use planning
Erosion Control Treatment Using Geocell and Wheat Straw for Slope Protection
Slope failure triggered by soil erosion under rainfall remains one of the most difficult problems in geotechnical engineering. Slope protection with planting vegetation can be used to reinforce the soil and stabilize the slope, but the early collapse of the planting soil before the complete growth of plants becomes a major issue for this method. This paper has proposed a composite soil treatment and slope protection method using the geocell structures and the wheat straw reinforcement. The geocell structures improve the stability of the planting soil and provide a stable and fixed environment for the vegetation, while the wheat straw reinforces the soil and also increases the fertility. The authors have performed a total of 9 experiments in this work that are classified into three groups, i.e., the unsupported slopes, the geocell reinforced, and the geocell and wheat straw composite reinforced with a consideration of three different rainfall intensities. The progressive slope failure development during the rainfall was assessed, as well as the soil erosion, the slope displacement, and the water content. The results show that the slope failure increases as the rainfall continues, and the soil degradation increases with the intensity of rainfall. The soil treatment using geocell improves the slope stability, but the geocell and wheat straw composite reinforcement has the best erosion control and slope protection