169 research outputs found
CIM-based Data-sharing Scheme for Online Calculation of Theoretical Line Loss
AbstractThis paper presents a new CIM-based data-sharing scheme for online calculation of theoretical line loss. The proposed method can read data from other applications which are being used in electric power company, such as electrical SCADA, Power Distribution Network GIS, DMIS, and so on. Moreover, the calculation model, which is used in theoretical calculation of line loss, is formed automatically. Users no longer need to manually input the structure data and operation data of grid. The operation data are updated from the DMIS and the SCADA continually, and the structure data are changing according to GIS and SCADA. Main electric wiring diagrams are also consistent with GIS and SCADA. Compared with conventional approaches, the proposed implementation can cut down the requirement of time and energy that line loss management must spend in maintaining the original data of calculation
CrowdCLIP: Unsupervised Crowd Counting via Vision-Language Model
Supervised crowd counting relies heavily on costly manual labeling, which is
difficult and expensive, especially in dense scenes. To alleviate the problem,
we propose a novel unsupervised framework for crowd counting, named CrowdCLIP.
The core idea is built on two observations: 1) the recent contrastive
pre-trained vision-language model (CLIP) has presented impressive performance
on various downstream tasks; 2) there is a natural mapping between crowd
patches and count text. To the best of our knowledge, CrowdCLIP is the first to
investigate the vision language knowledge to solve the counting problem.
Specifically, in the training stage, we exploit the multi-modal ranking loss by
constructing ranking text prompts to match the size-sorted crowd patches to
guide the image encoder learning. In the testing stage, to deal with the
diversity of image patches, we propose a simple yet effective progressive
filtering strategy to first select the highly potential crowd patches and then
map them into the language space with various counting intervals. Extensive
experiments on five challenging datasets demonstrate that the proposed
CrowdCLIP achieves superior performance compared to previous unsupervised
state-of-the-art counting methods. Notably, CrowdCLIP even surpasses some
popular fully-supervised methods under the cross-dataset setting. The source
code will be available at https://github.com/dk-liang/CrowdCLIP.Comment: Accepted by CVPR 202
SAM3D: Zero-Shot 3D Object Detection via Segment Anything Model
With the development of large language models, many remarkable linguistic
systems like ChatGPT have thrived and achieved astonishing success on many
tasks, showing the incredible power of foundation models. In the spirit of
unleashing the capability of foundation models on vision tasks, the Segment
Anything Model (SAM), a vision foundation model for image segmentation, has
been proposed recently and presents strong zero-shot ability on many downstream
2D tasks. However, whether SAM can be adapted to 3D vision tasks has yet to be
explored, especially 3D object detection. With this inspiration, we explore
adapting the zero-shot ability of SAM to 3D object detection in this paper. We
propose a SAM-powered BEV processing pipeline to detect objects and get
promising results on the large-scale Waymo open dataset. As an early attempt,
our method takes a step toward 3D object detection with vision foundation
models and presents the opportunity to unleash their power on 3D vision tasks.
The code is released at https://github.com/DYZhang09/SAM3D.Comment: Technical Report. The code is released at
https://github.com/DYZhang09/SAM3
GitNet: Geometric Prior-based Transformation for Birds-Eye-View Segmentation
Birds-eye-view (BEV) semantic segmentation is critical for autonomous driving
for its powerful spatial representation ability. It is challenging to estimate
the BEV semantic maps from monocular images due to the spatial gap, since it is
implicitly required to realize both the perspective-to-BEV transformation and
segmentation. We present a novel two-stage Geometry Prior-based Transformation
framework named GitNet, consisting of (i) the geometry-guided pre-alignment and
(ii) ray-based transformer. In the first stage, we decouple the BEV
segmentation into the perspective image segmentation and geometric prior-based
mapping, with explicit supervision by projecting the BEV semantic labels onto
the image plane to learn visibility-aware features and learnable geometry to
translate into BEV space. Second, the pre-aligned coarse BEV features are
further deformed by ray-based transformers to take visibility knowledge into
account. GitNet achieves the leading performance on the challenging nuScenes
and Argoverse Datasets. The code will be publicly available
SOOD: Towards Semi-Supervised Oriented Object Detection
Semi-Supervised Object Detection (SSOD), aiming to explore unlabeled data for
boosting object detectors, has become an active task in recent years. However,
existing SSOD approaches mainly focus on horizontal objects, leaving
multi-oriented objects that are common in aerial images unexplored. This paper
proposes a novel Semi-supervised Oriented Object Detection model, termed SOOD,
built upon the mainstream pseudo-labeling framework. Towards oriented objects
in aerial scenes, we design two loss functions to provide better supervision.
Focusing on the orientations of objects, the first loss regularizes the
consistency between each pseudo-label-prediction pair (includes a prediction
and its corresponding pseudo label) with adaptive weights based on their
orientation gap. Focusing on the layout of an image, the second loss
regularizes the similarity and explicitly builds the many-to-many relation
between the sets of pseudo-labels and predictions. Such a global consistency
constraint can further boost semi-supervised learning. Our experiments show
that when trained with the two proposed losses, SOOD surpasses the
state-of-the-art SSOD methods under various settings on the DOTA-v1.5
benchmark. The code will be available at https://github.com/HamPerdredes/SOOD.Comment: Accepted to CVPR 2023. Code will be available at
https://github.com/HamPerdredes/SOO
Diffusion-based 3D Object Detection with Random Boxes
3D object detection is an essential task for achieving autonomous driving.
Existing anchor-based detection methods rely on empirical heuristics setting of
anchors, which makes the algorithms lack elegance. In recent years, we have
witnessed the rise of several generative models, among which diffusion models
show great potential for learning the transformation of two distributions. Our
proposed Diff3Det migrates the diffusion model to proposal generation for 3D
object detection by considering the detection boxes as generative targets.
During training, the object boxes diffuse from the ground truth boxes to the
Gaussian distribution, and the decoder learns to reverse this noise process. In
the inference stage, the model progressively refines a set of random boxes to
the prediction results. We provide detailed experiments on the KITTI benchmark
and achieve promising performance compared to classical anchor-based 3D
detection methods.Comment: Accepted by PRCV 202
Maximizing frequency security margin via conventional generation dispatch and battery energy injection
To quantitatively evaluate the frequency stability margin during primary frequency control period following an under-frequency event, this paper presents a dynamic frequency response constrained optimal power flow (OPF) model. In this model, frequency security margin is defined and maximized by adjusting pre-disturbance generation outputs of conventional units and injections of battery energy storage system (BESS) immediately after a disturbance. Two nonlinear characteristics in speed-governing systems are considered and described as smooth and differentiable formulations to facilitate their incorporations into the proposed optimization model. A graphical tool is also provided to enable region-wise frequency security assessment based on the obtained maximum frequency security margin. Simulation results on WSCC 3-machine 9-bus system and New England 10-machine 39-bus system validate the suggested margin metric and the effectiveness of the proposed method
Mitigating Nitrous Oxide Emissions from Tea Field Soil Using Bioaugmentation with a Trichoderma viride
Land-use conversion from woodlands to tea fields in subtropical areas of central China leads to increased nitrous oxide (N2O) emissions, partly due to increased nitrogen fertilizer use. A field investigation of N2O using a static closed chamber-gas chromatography revealed that the average N2O fluxes in tea fields with 225 kg N ha−1 yr−1 fertilizer application were 9.4 ± 6.2 times higher than those of woodlands. Accordingly, it is urgent to develop practices for mitigating N2O emissions from tea fields. By liquid-state fermentation of sweet potato starch wastewater and solid-state fermentation of paddy straw with application of Trichoderma viride, we provided the tea plantation with biofertilizer containing 2.4 t C ha−1 and 58.7 kg N ha−1. Compared to use of synthetic N fertilizer, use of biofertilizer at 225 kg N ha−1 yr−1 significantly reduced N2O emissions by 33.3%–71.8% and increased the tea yield by 16.2%–62.2%. Therefore, the process of bioconversion/bioaugmentation tested in this study was found to be a cost-effective and feasible approach to reducing N2O emissions and can be considered the best management practice for tea fields
Phenotypic Plasticity of Staphylococcus aureus in Liquid Medium Containing Vancomycin
Phenotypic plasticity enables individuals to develop different phenotypes in a changing environment and promotes adaptive evolution. Genome-wide association study (GWAS) facilitates the study of the genetic basis of bacterial phenotypes, and provides a new opportunity for bacterial phenotypic plasticity research. To investigate the relationship between growth plasticity and genotype in bacteria, 41 Staphylococcus aureus strains, including 29 vancomycin-intermediate S. aureus (VISA) strains, were inoculated in the absence or presence of vancomycin for 48 h. Growth curves and maximum growth rates revealed that strains with the same minimum inhibitory concentration (MIC) showed different levels of plasticity in response to vancomycin. A bivariate GWAS was performed to map single-nucleotide polymorphisms (SNPs) associated with growth plasticity. In total, 227 SNPs were identified from 14 time points, while 15 high-frequency SNPs were mapped to different annotated genes. The P-values and growth variations between the two cultures suggest that non-coding region (SNP 738836), ebh (SNP 1394043), drug transporter (SNP 264897), and pepV (SNP 1775112) play important roles in the growth plasticity of S. aureus. Our study provides an alternative strategy for dissecting the adaptive growth of S. aureus in vancomycin and highlights the feasibility of bivariate GWAS in bacterial phenotypic plasticity research
Comparison of pneumonitis risk between immunotherapy alone and in combination with chemotherapy: an observational, retrospective pharmacovigilance study
Importance: Checkpoint inhibitor pneumonitis (CIP) is a rare but serious adverse event that may impact treatment decisions. However, there is limited information comparing CIP risks between immune checkpoint inhibitor (ICI) monotherapy and combination with chemotherapy due to a lack of direct cross-comparison in clinical trials.Objective: To determine whether ICI combination with chemotherapy is superior to ICI in other drug regimens (including monotherapy) in terms of CIP risk.Study Design and Methods: This observational, cross-sectional and worldwide pharmacovigilance cohort study included patients who developed CIP from the World Health Organization database (WHO) VigiBase and the US Food and Drug Administration Adverse Event Reporting System (FAERS) database. Individual case safety reports (ICSR) were extracted from 2015 to 2020 in FAERS and from 1967 to 2020 in VigiBase. Timing and reporting odds ratio (ROR) of CIP in different treatment strategies were used to detect time-to-onset and the risk of pneumonitis after different immunotherapy regimens.Results: A total of 93,623 and 114,704 ICI-associated ICSRs were included in this study from VigiBase and FAERS databases respectively. 3450 (3.69%) and 3278 (2.86%) CIPs occurred after therapy initiation with a median of 62 days (VigiBase) and 40 days (FAERS). Among all the CIPs, 274 (7.9%) and 537 (16.4%) CIPs were associated with combination therapies. ICIs plus chemotherapy combination was associated with pneumonitis in both VigiBase [ROR 1.35, 95% CI 1.18-1.52] and FAERS [ROR 1.39, 95% CI 1.27–1.53]. The combination of anti-PD-1 antibodies and anti-CTLA-4 antibodies with chemotherapy demonstrated an association with pneumonitis in both VigiBase [PD-1+chemotherapy: 1.76, 95% CI 1.52-2.05; CTLA-4+chemotherapy: 2.36, 95% CI 1.67-3.35] and FAERS [PD-1+chemotherapy: 1.70, 95% CI 1.52-1.91; CTLA-4+chemotherapy: 1.70, 95% CI 1.31-2.20]. Anti-PD-L1 antibodies plus chemotherapy combinations did not show the association.Conclusion: Compared to ICI in other drug regimens (including monotherapy), the combination of ICI plus chemotherapy is significantly associated with higher pneumonitis toxicity. Anti-PD-1/CTLA4 medications in combination with chemotherapy should be obviated in patients with potential risk factors for CIP.Trial Registration: clinicaltrials.gov, ChiCTR220005906
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