38 research outputs found

    BoxDiff: Text-to-Image Synthesis with Training-Free Box-Constrained Diffusion

    Full text link
    Recent text-to-image diffusion models have demonstrated an astonishing capacity to generate high-quality images. However, researchers mainly studied the way of synthesizing images with only text prompts. While some works have explored using other modalities as conditions, considerable paired data, e.g., box/mask-image pairs, and fine-tuning time are required for nurturing models. As such paired data is time-consuming and labor-intensive to acquire and restricted to a closed set, this potentially becomes the bottleneck for applications in an open world. This paper focuses on the simplest form of user-provided conditions, e.g., box or scribble. To mitigate the aforementioned problem, we propose a training-free method to control objects and contexts in the synthesized images adhering to the given spatial conditions. Specifically, three spatial constraints, i.e., Inner-Box, Outer-Box, and Corner Constraints, are designed and seamlessly integrated into the denoising step of diffusion models, requiring no additional training and massive annotated layout data. Extensive results show that the proposed constraints can control what and where to present in the images while retaining the ability of the Stable Diffusion model to synthesize with high fidelity and diverse concept coverage. The code is publicly available at https://github.com/Sierkinhane/BoxDiff.Comment: Accepted by ICCV 2023. The paper is still being revised for better organization and comparison. Code is available at: https://github.com/Sierkinhane/BoxDif

    Open-World Weakly-Supervised Object Localization

    Full text link
    While remarkable success has been achieved in weakly-supervised object localization (WSOL), current frameworks are not capable of locating objects of novel categories in open-world settings. To address this issue, we are the first to introduce a new weakly-supervised object localization task called OWSOL (Open-World Weakly-Supervised Object Localization). During training, all labeled data comes from known categories and, both known and novel categories exist in the unlabeled data. To handle such data, we propose a novel paradigm of contrastive representation co-learning using both labeled and unlabeled data to generate a complete G-CAM (Generalized Class Activation Map) for object localization, without the requirement of bounding box annotation. As no class label is available for the unlabelled data, we conduct clustering over the full training set and design a novel multiple semantic centroids-driven contrastive loss for representation learning. We re-organize two widely used datasets, i.e., ImageNet-1K and iNatLoc500, and propose OpenImages150 to serve as evaluation benchmarks for OWSOL. Extensive experiments demonstrate that the proposed method can surpass all baselines by a large margin. We believe that this work can shift the close-set localization towards the open-world setting and serve as a foundation for subsequent works. Code will be released at https://github.com/ryylcc/OWSOL

    Dynamically Masked Discriminator for Generative Adversarial Networks

    Full text link
    Training Generative Adversarial Networks (GANs) remains a challenging problem. The discriminator trains the generator by learning the distribution of real/generated data. However, the distribution of generated data changes throughout the training process, which is difficult for the discriminator to learn. In this paper, we propose a novel method for GANs from the viewpoint of online continual learning. We observe that the discriminator model, trained on historically generated data, often slows down its adaptation to the changes in the new arrival generated data, which accordingly decreases the quality of generated results. By treating the generated data in training as a stream, we propose to detect whether the discriminator slows down the learning of new knowledge in generated data. Therefore, we can explicitly enforce the discriminator to learn new knowledge fast. Particularly, we propose a new discriminator, which automatically detects its retardation and then dynamically masks its features, such that the discriminator can adaptively learn the temporally-vary distribution of generated data. Experimental results show our method outperforms the state-of-the-art approaches

    Laboratory Study of the Heavy Weight Reversible Invert Emulsion Drilling Fluid

    Get PDF
    A novel reversible invert emulsion drilling fluid which is useful in resolving the contradiction between drilling efficiency, cementing and environmental effect has been invented based on the protonation reversibility of amine. The new drilling fluid has reversible emulsion-phase behavior. The formulation of the reversible invert emulsion drilling fluid was: white oil (5)+25% CaCl2 brine+50% weight agent ZFU-3+1.5% organoclay+0.5% lime +4.5% reversible emulsifier UPSG-1+1% wetting agent DYSL-3+an appropriate amount barite, oleaginous fluid to non-oleaginous fluid-ratio was 50/50, drilling fluid density was 1.9 kg/L, weight agent ZFU is sodium formate. Comprehensive performance evaluation with laboratory test showed that the new drilling fluid could be readily and reversibly converted from a water-in-oil emulsion to an oil-in water emulsion and back to a water-in-oil emulsion using an acid-based chemical switch. And before and after converting the emulsion mud maintains good performance, with emulsion-breaking voltage of 900-1,100 V, resistance to temperature of 150℃, HEHP filter loss of less than 6 ml. Additionally, the filter cake and oily cuttings could be treated easily. This suggests that the reversible invert emulsion drilling fluid has both merits of oil-based fluid and water –based fluids, and all properties are excellent. The reversible invert emulsion drilling fluid is capable of resolving the problems with the application of conventional oil-based drilling fluid. The density of the reversible invert emulsion is 1.9 kg/L, which is also better than the traditional reversible invert emulsion drilling fluid

    Global research status and frontiers on microvascular invasion of hepatocellular carcinoma: A bibliometric and visualized analysis

    Get PDF
    IntroductionOver the past decade, several studies on the microvascular invasion (MVI) of hepatocellular carcinoma (HCC) have been published. However, they have not quantitatively analyzed the remarkable impact of MVI. Therefore, a more comprehensive understanding of the field is now needed. This study aims to analyze the evolution of HCC-MVI research and to systematically evaluate the scientific outputs using bibliometric citation analysis.MethodsA systematic search was conducted on the Web of Science Core Collection on 2 May 2022 to retrieve studies on HCC-MVI published between 2013 and 2022. Then, a bibliometric analysis of the publications was performed using CiteSpace, VOSviewer, and other visualization tools.ResultsA total of 1,208 articles on HCC MVI were identified. Of these, China (n = 518) was the most prolific country, and Fudan University (n = 90) was the most notable institution. Furthermore, we observed that Lau Wan Yee participated in most studies (n = 26), and Frontiers in Oncology (IF2020:6.24) published the highest number of documents (n = 49) on this subject, with 138 publications. The paper “Bray F, 2018, CA-CANCER J CLIN, V68, P394” has the highest number of co-cited references, with 119 citations. In addition, the top three keywords were “survival”, “recurrence”, and “microvascular invasion”. Moreover, the research hot spots and frontiers of HCC-MVI for the last 3 years included imaging characteristics and transarterial chemoembolization (TACE) therapy studies.ConclusionsThis study comprehensively summarized the most significant HCC-MVI documents from past literature and highlighted key contributions made to the advancement of this subject and the advancement of this field over the past decade. The trend of MVI research will gradually shift from risk factors and prognosis studies to imaging characteristics and TACE therapy studies

    Application of fast track surgery strategy in perioperative period of primary suture of laparoscopic choledocholithotomy

    No full text
    ObjectiveTo investigate the clinical application value of fast track surgery strategy (EARS) in the perioperative period of primary suture of laparoscopy in the treatment of common bile duct stones. MethodsA total of 64 patients with gallstones complicated by common bile duct stones who were hospitalized in Department of Hepatobiliary Surgery in The Second People′s Hospital of Chengdu from October 2015 to February 2016 were enrolled, and according to the treatment in the perioperative period, the patients were divided into EARS group (32 patients) and control group (32 patients). Clinical indices and complications were compared between the two groups. The t-test was used for comparison of continuous data between groups, and the chi-square test was used for comparison of categorical data between groups. ResultsCompared with the control group, the ERAS group had significantly shortened time of extraction of drainage tube (1.6±0.9 d vs 2.7±1.0 d, t=-5.675, P<0.01) and length of hospital stay (5.1±1.0 d vs 6.8±1.1 d, t=-5.910, P<0.01), significantly shorter time to first ambulation (1.0±0.3 d vs 1.6±0.7 d, t=-4.313, P<0.01) and time to intestinal functional recovery (1.1±0.4 d vs 1.8±0.6 d, t=-4.842, P<0.01), a significantly shortened time to stopping infusion after surgery (3.8±1.0 d vs 4.9±1.2 d, t=-3.923, P<0.01), significantly reduced total hospital costs (17 433.5±1411.3 ten thousand yuan vs 26 651.6±2945.8 ten thousand yuan, t=-15.942, P<0.001), a significantly lower proportion of patients who experienced pain after surgery [4 (12.5%) vs 13 (40.6%), χ2=6.490, P=0.011], and significantly lower levels of alanine aminotransferase (105.25±35.34 U/L vs 179.00±48.64 U/L, t=-5.973, P<0.05) and total bilirubin (50.78±12.60 μmol/L vs 79.70±18.56 μmol/L, t=-7.090, P<0.05) after surgery. ConclusionEARS is highly practical in the perioperative period of laparoscopic surgery and can promote patients′ rapid recovery. Therefore, it holds promise for clinical application

    The existence of solutions of Hadamard fractional differential equations with integral and discrete boundary conditions on infinite interval

    Get PDF
    In this article, the properties of solutions of Hadamard fractional differential equations are investigated on an infinite interval. The equations are subject to integral and discrete boundary conditions. A new proper compactness criterion is introduced in a unique space. By applying the monotone iterative technique, we have obtained two positive solutions. And, an error estimate is also shown at the end. This study innovatively uses a monotonic iterative approach to study Hadamard fractional boundary-value problems containing multiple fractional derivative terms on infinite intervals, and it enriches some of the existing conclusions. Meanwhile, it is potentially of practical significance in the research field of computational fluid dynamics related to blood flow problems and in the direction of the development of viscoelastic fluids

    Multi-Electrode Resistivity Probe for Investigation of Local Temperature Inside Metal Shell Battery Cells via Resistivity: Experiments and Evaluation of Electrical Resistance Tomography

    No full text
    Direct Current (DC) electrical resistivity is a material property that is sensitive to temperature changes. In this paper, the relationship between resistivity and local temperature inside steel shell battery cells (two commercial 10 Ah and 4.5 Ah lithium-ion cells) is innovatively studied by Electrical Resistance Tomography (ERT). The Schlumberger configuration in ERT is applied to divide the cell body into several blocks distributed in different levels, where the apparent resistivities are measured by multi-electrode surface probes. The investigated temperature ranges from −20 to 80 °C. Experimental results have shown that the resistivities mainly depend on temperature changes in each block of the two cells used and the function of the resistivity and temperature can be fitted to the ERT-measurement results in the logistical-plot. Subsequently, the dependence of resistivity on the state of charge (SOC) is investigated, and the SOC range of 70%–100% has a remarkable impact on the resistivity at low temperatures. The proposed approach under a thermal cool down regime is demonstrated to monitor the local transient temperature

    Exploring work readiness: A qualitative descriptive study of self-perceptions among new graduate nurses

    No full text
    Background: Reduced work readiness is associated with elevated turnover rates, necessitating efforts to enhance the positive work readiness of newly graduated nurses to alleviate the shortage in the nursing workforce. Research into the work readiness of recent nursing graduates in China is still in its infancy. Most studies employ quantitative research methods, and further exploration of the self-perception of work readiness among new nurses in China is required. Objectives: This study aimed to investigate genuine experiences and self-perceptions of work readiness among new graduate nurses. Design: A qualitative descriptive study. Methods: Sixteen new nurses from a provincial tertiary hospital in China were included in this study, which adhered to the consolidated criteria for reporting qualitative research (COREQ) checklist for reporting. The data collection process involved conducting semi-structured interviews from September to October 2021. Inductive content analysis was employed to analyze the interview data. Results: The study identified four themes encompassing new nurses' real-life experiences and self-perceptions of work readiness: psychological stress, emotional conflict, empathy fatigue, and ethical dilemmas. Psychological stress comprised three subthemes: knowledge and skill deficits, communication barriers, and fear. Empathy fatigue was primarily characterized by psychological and physical symptoms. Ethical dilemmas involved conflicts over differences in values and between clinical reality and standardized nursing practice. Conclusion: Drawing from the self-perceptions of work readiness among new nurses found in this study, nursing administrators and educators must enhance the existing transition support program for new nurses. Additionally, the establishment of individualized training programs is recommended to further improve the work readiness of new nurses

    Long Term Outcomes of No-Touch Isolation Principles Applied in Pancreaticoduodenectomy for Treatment of Pancreatic Adenocarcinoma: A Multicenter Retrospective Study with Propensity Score Matching

    No full text
    Background: The recurrence and liver metastasis rates are still high in pancreatic head cancer with curative surgical resection. A no-touch isolation principle in pancreaticoduodenectomy (PD) may improve this situation, however, the exact advantages and efficacy of these principles have not been confirmed. Materials and methods: Among 370 patients who underwent PD, three centers were selected and classified into two groups: the no-touch PD group (n = 70) and the conventional PD group (n = 300). Propensity score matching was used to control for selection bias at a ratio of 1:1. The confounding variables were age, sex, body mass index, adjuvant chemotherapy, carbohydrate antigen 19-9, tumor size and tumor differentiation. Results: Patients in the no-touch PD group had better overall survival (OS) and disease-free survival (DFS) than those in the conventional PD group (OS: 17 vs. 13 months, p = 0.0035, DFS: 15 vs. 12 months, p = 0.087), with lower 1- and 2-year disease-related mortality rates (1-year: 32.9% vs. 47%, p = 0.032; 2-year: 42.5% vs. 82% p = 0.000) and recurrence and liver metastasis rates (1-year: 30.0% vs. 43.3%, p = 0.041; 2-year: 34.3% vs. 48.7%, p = 0.030). Compared with the matched conventional PD group, the no-touch PD group also had a better OS (17 vs. 12 months, p = 0.032). Conclusions: Our study showed the no-touch isolation principle may be a better choice to improve long-term survival for pancreatic cancer patients
    corecore