Research into the characteristics of horizontal gaseous jets underwater

The gaseous jet of the solid rocket motor running under water is influenced by both gravity and buoyancy, which will have a significant influence on the flow field structure and thrust of the motor, especially in the initial period when vehicles are launching horizontally. The work in this paper consists of three parts: firstly, to understand the mechanism of the thrust oscillation characteristics and the jet structure of a solid rocket motor running under water, as affected by gravity and buoyancy, a 3-d numerical simulation using the volume of fluid (VOF) model was established. Compared with those results neglecting gravity and buoyancy, conclusions were obtained that the jet structure, considering gravity and buoyancy, are more consistent with the experimental results. Secondly, the principle of momentum was used to analyze the flow field structure and the thrust oscillating characteristics in the initial period of operation. Finally, after analyzing the density gradient along the axis of the motor, results indicated that the length of jets under the influence of gravity and buoyancy varies linearly and the slope of the line is related to the working conditions. Comparing the trajectories under different conditions, a common theme emerged. The laws of thermodynamics are also used to simulate the jets as gas-water-vapor, three-phase, systems. The effect of phase transitions on the structure of jets and the characteristics of their thrust form the key conclusions

LaunchpadGPT: Language Model as Music Visualization Designer on Launchpad

Launchpad is a musical instrument that allows users to create and perform music by pressing illuminated buttons. To assist and inspire the design of the Launchpad light effect, and provide a more accessible approach for beginners to create music visualization with this instrument, we proposed the LaunchpadGPT model to generate music visualization designs on Launchpad automatically. Based on the language model with excellent generation ability, our proposed LaunchpadGPT takes an audio piece of music as input and outputs the lighting effects of Launchpad-playing in the form of a video (Launchpad-playing video). We collect Launchpad-playing videos and process them to obtain music and corresponding video frame of Launchpad-playing as prompt-completion pairs, to train the language model. The experiment result shows the proposed method can create better music visualization than random generation methods and hold the potential for a broader range of music visualization applications. Our code is available at https://github.com/yunlong10/LaunchpadGPT/.Comment: Accepted by International Computer Music Conference (ICMC) 202

Five-Section Trajectory Design of Thick Glutenite Reservoir in Shengli Oilfield

Many blocks of Shengli Oilfield are located in urban areas, and the site selection of well sites is limited. In order to meet the needs of reservoir development and deployment, five-section trajectory is increasingly used. Difficulty in site selection results in directional well development, and reservoir deployment requires vertical well development. In order to resolve the two contradictions, five-section trajectory is used in the well design, and vertical drilling after hitting the target. The problems with this type of trajectory are high torque drag and easier fatigue of the drilling pipe. When the displacement is small, the effect is small. When the displacement is large, it will cause engineering complexity such as difficulty drilling weight transfer and fatigue of drilling pipe. Aiming at the shortcomings of the five-section trajectory, with the help of existing drill string force analysis software, the parameters of the five-section trajectory were analyzed, and reasonable values were recommended to provide an optimization idea for the five-section trajectory

Geochemistry of Late Triassic pelitic rocks in the NE part of Songpan-Ganzi Basin, western China: Implications for source weathering, provenance and tectonic setting

AbstractMajor, trace and rare earth element (REE) concentrations of Late Triassic sediments (fine-grained sandstones and mudstones) from Hongcan Well 1 in the NE part of the Songpan-Ganzi Basin, western China, are used to reveal weathering, provenance and tectonic setting of inferred source areas. The Chemical Index of Alteration (CIA) reflects a low to moderate degree of chemical weathering in a cool and somewhat dry climate, and an A-CN-K plot suggests an older upper continental crust provenance dominated by felsic to intermediate igneous rocks of average tonalite composition. Based on the various geochemical tectonic setting discrimination diagrams, the Late Triassic sediments are inferred to have been deposited in a back-arc basin situated between an active continental margin (the Kunlun-Qinling Fold Belt) and a continental island arc (the Yidun Island Arc). The Triassic sediments in the study area underwent a rapid erosion and burial in a proximal slope-basin environment by the petrographic data, while the published flow directions of Triassic turbidites in the Aba-Zoige region was not supported Yidun volcanic arc source. Therefore, we suggest that the Kunlun-Qinling terrane is most likely to have supplied source materials to the northeast part of the Songpan-Ganzi Basin during the Late Triassic

LLMVA-GEBC: Large Language Model with Video Adapter for Generic Event Boundary Captioning

Our winning entry for the CVPR 2023 Generic Event Boundary Captioning (GEBC) competition is detailed in this paper. Unlike conventional video captioning tasks, GEBC demands that the captioning model possess an understanding of immediate changes in status around the designated video boundary, making it a difficult task. This paper proposes an effective model LLMVA-GEBC (Large Language Model with Video Adapter for Generic Event Boundary Captioning): (1) We utilize a pretrained LLM for generating human-like captions with high quality. (2) To adapt the model to the GEBC task, we take the video Q-former as an adapter and train it with the frozen visual feature extractors and LLM. Our proposed method achieved a 76.14 score on the test set and won the first place in the challenge. Our code is available at https://github.com/zjr2000/LLMVA-GEBC .Comment: Winner solution to Generic Event Boundary Captioning task in LOVEU Challenge (CVPR 2023 workshop

Plant-Based Sustainable Self-Cleaners in Nanotechnology Era: From Mechanism to Assembling

Nature has always been a resource of inspiration for humans, providing valuable lessons that have led to innovative solutions throughout history. Observing the micro-nano roughness structure of bio-surfaces has led to the discovery of natural self-cleaning surfaces for over 25 years. This has sparked a new field of research with valuable applications. Numerous self-cleaning products made from plant extracts have been created by replicating the natural purifying abilities of plant surfaces. Significant literature exists on the development, classification, extraction, and production of self-cleaning agents for diverse industries through a thorough understanding of bio-cleaning mechanisms. Various methods have been developed to synthesize these surfaces, including immersion, electrochemical deposition, emulsion, electrospinning, phase-separation, Chemical-Vapor-Deposition (CVD), spray coating, wet chemical reaction, and three-dimensional printing (3D-printing), among others. Currently, the primary objective is to gain knowledge from nature and utilize it to develop novel products for food, pharmaceutical, and related industries. Natural plant-based self-cleaning surfaces can be characterized by their superhydrophobicity and superhydrophilicity regimes. The process of 3D-printing is a computer-based technique that builds up three-dimensional objects through the layer-by-layer deposition of materials. The creation of effective self-cleaning surfaces with unique wettability, chemical properties, and microstructure depends on the design and engineering of solid surfaces

Research on energy dissipation characteristics and coal burst tendency of fissured coal mass

Coal burst tendency is the natural property of whether coal rock mass can have coal burst, and the distribution of fissures has an important influence on it. In order to study the influence mechanism of the original coal fissures on the energy dissipation characteristics and coal burst tendency, the PFC2D numerical simulation method was used to conduct uniaxial compression tests on coal specimens with different fracture types. The results show that: ①With the increase of the inclination angle of the fissure, the compressive strength and elastic modulus of the macroscopic mechanical parameters show a trend of decreasing first and then increasing; when the inclination angle of the fissure is 30, both of them reach the minimum value. The relationship between the macro-mechanical parameters of different fracture types is: non-coplanar parallel double-fissure specimen < single-fissure specimen < co-planar discontinuous double-fissure specimen.②The variation law of elastic strain energy and total strain energy is similar to that of macroscopic mechanical parameters. The parallel and non-coplanar fracture specimens form an energy dissipation structure between the fissures, and the coplanar discontinuous double-fissure specimen forms an energy concentration area between the fissures, revealing the intrinsic reason for the relationship between the elastic energy of different fracture types. ③The coal burst tendency is analyzed from the two perspectives of the ability of coal and rock to store elastic energy and the ability to release elastic energy after failure, and two coal burst tendency indicators, elastic energy storage rate and elastic energy release rate, are proposed. ④With the increase of the fissure inclination angle, both the elastic energy storage rate and the elastic energy release rate showed a trend of first decreasing and then increasing; when the fissure inclination angle was 30, the two coal burst propensity indexes both achieved the minimum value. The relationship between the coal burst tendency of different fracture types is: non-coplanar parallel double-fissure specimen < single-fissure specimen < co-planar discontinuous double-fissure specimen. The distribution of fissures has a significant coal burst on the coal burst tendency of coal mass, and the factor of fissures should be considered in the evaluation of the coal burst tendency of coal and rock mass and the prevention and control of rock burst

Mechanical-force-induced non-local collective ferroelastic switching in epitaxial lead-titanate thin films.

Ferroelastic switching in ferroelectric/multiferroic oxides plays a crucial role in determining their dielectric, piezoelectric, and magnetoelectric properties. In thin films of these materials, however, substrate clamping is generally thought to limit the electric-field- or mechanical-force-driven responses to the local scale. Here, we report mechanical-force-induced large-area, non-local, collective ferroelastic domain switching in PbTiO3 epitaxial thin films by tuning the misfit-strain to be near a phase boundary wherein c/a and a1/a2 nanodomains coexist. Phenomenological models suggest that the collective, c-a-c-a ferroelastic switching arises from the small potential barrier between the degenerate domain structures, and the large anisotropy of a and c domains, which collectively generates much larger response and large-area domain propagation. Large-area, non-local response under small stimuli, unlike traditional local response to external field, provides an opportunity of unique response to local stimuli, which has potential for use in high-sensitivity pressure sensors and switches