PointCLIP V2: Adapting CLIP for Powerful 3D Open-world Learning

Contrastive Language-Image Pre-training (CLIP) has shown promising open-world performance on 2D image tasks, while its transferred capacity on 3D point clouds, i.e., PointCLIP, is still far from satisfactory. In this work, we propose PointCLIP V2, a powerful 3D open-world learner, to fully unleash the potential of CLIP on 3D point cloud data. First, we introduce a realistic shape projection module to generate more realistic depth maps for CLIP's visual encoder, which is quite efficient and narrows the domain gap between projected point clouds with natural images. Second, we leverage large-scale language models to automatically design a more descriptive 3D-semantic prompt for CLIP's textual encoder, instead of the previous hand-crafted one. Without introducing any training in 3D domains, our approach significantly surpasses PointCLIP by +42.90%, +40.44%, and +28.75% accuracy on three datasets for zero-shot 3D classification. Furthermore, PointCLIP V2 can be extended to few-shot classification, zero-shot part segmentation, and zero-shot 3D object detection in a simple manner, demonstrating our superior generalization ability for 3D open-world learning. Code will be available at https://github.com/yangyangyang127/PointCLIP_V2

Concepts, Structure and Developments of High-Reliability Cyber-Physical Fusion Based Coordinated Planning for Distribution System

Coordinated control is imperative for the distribution network with the integration of wind power, photovoltaic system, and energy storage system. Meanwhile, the advanced automation terminal, intelligent control technology, and information communication technologies have greatly promoted the informatization of distribution networks which also increase the correlation between the physical system (primary system) and the cyber system (secondary system). Hence, it is critical to comprehensively coordinate the planning of the cyber-physical system for building a highly reliable power grid. This work summarizes a series of challenges brought by the highly coupled cyber-physical system, such as the primary and secondary collaborated planning models and solution algorithms. Then, the reliability assessment theories of cyber-physical systems and their application in distribution network planning models are introduced. Finally, three development directions of distribution network planning in the future are proposed, considering primary and secondary system coordinated planning

Observation of tunable topological polaritons in a cavity waveguide

Topological polaritons characterized by light-matter interactions have become a pivotal platform in exploring new topological phases of matter. Recent theoretical advances unveiled a novel mechanism for tuning topological phases of polaritons by modifying the surrounding photonic environment (light-matter interactions) without altering the lattice structure. Here, by embedding a dimerized chain of microwave helical resonators (electric dipole emitters) in a metallic cavity waveguide, we report the pioneering observation of tunable topological phases of polaritons by varying the cavity width which governs the surrounding photonic environment and the strength of light-matter interactions. Moreover, we experimentally identified a new type of topological phase transition which includes three non-coincident critical points in the parameter space: the closure of the polaritonic bandgap, the transition of the Zak phase, and the hybridization of the topological edge states with the bulk states. These results reveal some remarkable and uncharted properties of topological matter when strongly coupled to light and provide an innovative design principle for tunable topological photonic devices.Comment: 6 pages, 4 figure

Study of Shape Memory Polymer Composites from Polymerization Induced Phase Separation Process

Polymer composites are taking the place of traditional materials in many fields. They are preferred in engineering structures due to the advantages in strength, stiffness, thermostability, corrosion resistance, and ductility at high temperatures. Study of PCL-based shape memory polymer composite can expand its application. And in order to fully understand SMP properties, a series of comprehensive testing is required. Samples with different PCL percentages must be made by using a standard and optimized procedure to eliminate unwanted variables, and to ensure the amount of PCL in samples is the only variable. The DSC test on the SMP samples shows that there are two transition phases. One is at 53 °C and indicated as PCL melting temperature; another one is at 138.5 °C, indicated to be the glass transition phase. Shape memory behavior tests on the SMP samples show that the PCL-based polymer composite has significant shape recovery ability. The ability of recovery is proportional with the amount of PCL in the sample. And the recovery performance is shown in both strain and stress recovery. The mechanical properties of SMP composite are determined by compression tests. Tests are performed on each specimen with different PCL percentages. The maximum compressive stress is higher in specimens that have a higher amount of PCL, and this result agrees with results from the shape memory test. Finally, the SMP composites are observed with SEM. A unique globule structure is shown in the specimens regardless of their PCL percentages. This globule structure is totally different from the structure in pure epoxy. The reason for this difference is still unknown and needs to be determined with further research

Diamond ultra-small electrodes for integration with GaN electronics

As a novel electrode material, diamond possesses unique properties, such as the widest potential window of water dissociation in all electrode materials, extreme chemical stability, low background current density and biocompatibility, being all in the wish-list of biologists, who want to perform biochemical sensing. And it would be significant to combine the diamond sensor technology with other mainstream technologies for biochemical sensing, e.g. parallel sensing with fluorescence microscopy, potentiometry sensing, on-wafer signal conditioning, even the realisation of LOC (Lab On Chip) concept etc. However, traditional diamond micro devices are deposited mostly on silicon substrate, which is not transparent to visible light and also show limited biocompatibility. Particularly, monolithic integration into Si-based CMOS circuits may not be possible since silicon-based electronics can hardly withstand the CVD conditions of diamond deposition. In this study, a new substrate for CVD diamond electrodes-single crystalline sapphire is adopted. Sapphire is a wide-bandgap semiconductor, besides being highly transparent and robust, it serves as a substrate material for a wide range of electronics. Among them, high-performance GaN electronics are especially interesting for this study, since they may withstand the harsh growth conditions of CVD diamond films, thus allowing the monolithic integration of GaN electronics into diamond sensors for signal conditioning and processing. As a precondition of the monolithic integration, electrode-grade diamond film needs to be deposited on the sapphire substrate. In this study, technologies are developed, leading to realization of large-area (up to 2 inch) DOS (diamond-on-sapphire) materials with well-preserved diamond material properties for electrode applications. Based on DOS (diamond on sapphire), several state-of-art diamond ultra-small electrode devices have been realized, targeting several novel applications

Effects of apparent temperature on cardiovascular disease admissions in rural areas of Linxia Hui Autonomous Prefecture

Abstract Cardiovascular disease (CVD) is a major threat to public health worldwide. The relationship between CVD and temperature has been widely reported in developed countries and regions. However, there are few studies of severe CVD in poor rural areas of developing countries. Therefore, this study aimed to explore the relationship between CVD and apparent temperature (AT) in a rural area of Linxia Hui Autonomous Prefecture, China. Daily CVD admission data and meteorological data were collected from Linxia between 2014 and 2015. The media of AT was used as the reference temperature to estimate the cumulative relative risk (RR) of CVD admission. The distributed lag non-linear models were used to examine the association between AT and cumulative RR of CVD admission at lag 0–21 days. In Linxia, high AT (20 °C) had a persistent adverse effect on cumulative RR of CVD admissions, and the RR increased with increasing lag days. Cold (− 10 °C) had a protective effect on the first and later lag days (lag 0–14 and lag 0–21). Adults (aged < 65 years) and females were more susceptible to the effects of heat than males and the elderly (aged ≥ 65 years). In Linxia, China, extremely high AT is an important risk factor for CVD hospitalizations in suburban and rural populations

Cardiovascular admission risk attributable to hot apparent temperature: a study in a rural area of northwest China

Cardiovascular disease (CVD) is the leading cause of mortality worldwide, posing a significant threat to public health. Research on the relationship between CVD and temperature has primarily focused on developed urban settings, with limited studies conducted in rural regions with lower levels of development. Additionally, compared to relative risks, attributable risks can provide more information when assessing the risk of CVD hospitalizations associated with exposure to apparent temperature (AT). Apparent temperature is a composite temperature index that takes into account both meteorological factors and temperature, providing an objective reflection of human thermal sensation. Therefore, this study investigates the impact of AT on CVD hospitalization and quantifies the burden of CVD admission in the rural areas of China. We employed the distributed lag non-linear model (DLNM) to estimate the relationship between AT and the relative risk (RR) of CVD hospitalization. Finally, we used attributable risk methods to quantify this relationship further.</p