Motion Path Research Articles

Numerical Simulation of Rainfall‐induced Xianchi Reservoir Landslide in Yunyang, Chongqing, China

AbstractA calamitous landslide happened at 22:00 on September 1, 2014 in the Yunyang area of Chongqing City, southwest China, enforcing the evacuation of 508 people and damaging 23 buildings. The landslide volume comprised 1.44 million m3 of material in the source area and 0.4 million m3 of shoveled material. The debris flow runout extended 400 m vertically and 1600 m horizontally. The Xianchi reservoir landslide event has been investigated as follows: (1) samples collected from the main body of landslide were carried out using GCTS ring shear apparatus; (2) the parameters of shear and pore water pressure have been measured; and (3) the post‐failure characteristics of landslide have been analyzed using the numerical simulation method. The excess pore‐water pressure and erosion in the motion path are considered to be the key reasons for the long‐runout motion and the scale‐up of landslides, such as that at Xianchi, were caused by the heavy rainfall. The aim of this paper is to acquired numerical parameters and the basic resistance model, which is beneficial to improve simulation accuracy for hazard assessment for similar to potentially dangerous hillslopes in China and elsewhere.

Seasonal and Interannual Movement of the Mindanao Current Retroflection at the Pacific Entrance of the Indonesian Seas

Abstract The seasonal and interannual variations of the Mindanao Current (MC) retroflection are studied using surface geostrophic currents of satellite altimeters covering January 1993–December 2019. The results show that the Mindanao Current mainstream retroflects back to the Pacific Ocean north of the Talaud Islands in boreal summer and intrudes into the northern Maluku Sea in boreal winter. The variation of the MC retroflection has resulted in the seasonal movement of the sea surface color fronts at the entrance of the Indonesian seas, both of which are highly correlated to the seasonal transport variations of the North Equatorial Countercurrent, lagging the latter due to the westward propagation of the seasonal Rossby waves. The MC retroflection and sea surface color fronts are found to move synchronously on interannual time scales at the Pacific entrance of the Indonesian seas, with the Niño-3.4 index lagging by about 2 months. The MC retroflection intrudes anomalously deeper than the seasonal cycle into the northern Maluku Sea in El Niño winters, while it tends to take a leaping path in La Niña winters. During El Niño summers, the leaping path of the MC is changed into a penetrating path sometimes. Significance Statement The Mindanao Current is the western boundary current (WBC) of the North Pacific Ocean tropical gyre and is much stronger than the ocean interior gyre circulation. This equatorward WBC forces strong exchanges between the equatorial Pacific and the marginal seas as it turns eastward at the entrance of the Indonesian seas. The path of the Mindanao Current retroflection is very important for Rossby wave reflection and for Indo-Pacific interbasin exchange leading to global repercussions, both of which are thought to be controlled by linear dynamics in the past. Here, we disclose the seasonal and interannual movement of the retroflection path, showing strong nonlinear dynamics important for ENSO and interocean exchange.

A cognitive approach to concept of visualization in problem-solving

Any ball or small stone that is thrown follows a certain path. Many of us have experienced throwing objects towards a specific goal many times. If we throw a ball to someone or against something, the ball will follow a certain path, a visualized motion. Hopefully you can imagine a motion path if you are asked to throw something towards a target some 10 meters away. Somehow we can imagine the height and path in order to get the ball (or small stone) in the basket or what we are aiming at. If we want to shoot a basketball to go into the basket, we consider elevation angle and initial velocity also. Most of us humans do that without thinking about it.

Demography and movement patterns of a freshwater ciliate: The influence of oxygen availability.

In freshwater habitats, aerobic animals and microorganisms can react to oxygen deprivation by a series of behavioural and physiological changes, either as a direct consequence of hindered performance or as adaptive responses towards hypoxic conditions. Since oxygen availability can vary throughout the water column, different strategies exist to avoid hypoxia, including that of active 'flight' from low-oxygen sites. Alternatively, some organisms may invest in slower movement, saving energy until conditions return to more favourable levels, which may be described as a 'sit-and-wait' strategy. Here, we aimed to determine which, if any, of these strategies could be used by the freshwater ciliate Tetrahymena thermophila when faced with decreasing levels of oxygen availability in the culture medium. We manipulated oxygen flux into clonal cultures of six strains (i.e. genotypes) and followed their growth kinetics for several weeks using automated image analysis, allowing to precisely quantify changes in density, morphology and movement patterns. Oxygen effects on demography and morphology were comparable across strains: reducing oxygen flux decreased the growth rate and maximal density of experimental cultures, while greatly expanding the duration of their stationary phase. Cells sampled during their exponential growth phase were larger and had a more elongated shape under hypoxic conditions, likely mirroring a shift in resource investment towards individual development rather than frequent divisions. In addition to these general patterns, we found evidence for intraspecific variability in movement responses to oxygen limitation. Some strains showed a reduction in swimming speed, potentially associated with a 'sit-and-wait' strategy; however, the frequent alteration of movement paths towards more linear trajectories also suggests the existence of an inducible 'flight response' in this species. Considering the inherent costs of turns associated with non-linear movement, such a strategy may allow ciliates to escape suboptimal environments at a low energetic cost.

Модель информационно-телекоммуникационного взаимодействия между автоматизированными транспортными средствами в условиях неполного покрытия мобильными сетями

Objective: in order to improve safety, as well as optimize the path of movement in everyday life to reduce the time on the road, there are now more and more prerequisites for the introduction of highly automated and fully automated vehicles into various spheres of human life. This will optimize and improve the road system of the country as a whole, and most importantly — reduce accidents and, consequently, improve road safety. When implementing these vehicles, it is necessary to develop an algorithm for communication between different road users under different conditions and distances between objects. Methods: this study uses simulation modeling methods, the method of tabular and graphical data display, the method of factor analysis, methods of model experiment, as well as the method of expert assessments. Results: within the framework of the work, an algorithm has been developed for transmitting messages with different content and priority information between two highly automated / fully automated vehicles or a vehicle with an automated state infrastructure using various communication channels, as well as a simulation model based on it, which was created in the AnyLogic modeling environment. The use of different priorities allows you to guarantee the minimum delivery time of the most important messages containing information for vehicle management. As a result of the simulation, histograms of the probabilistic-temporal characteristics of the transmission of messages of various priorities and messages confirming their delivery were obtained using various communication channels. Practical significance: the simulation results make it possible to assess the quality and time of message delivery under specified conditions and to ensure effective transmission of information by changing the intensity and size of messages, the use of various communication channels and their speeds, and so on.

The expression of decision and learning variables in movement patterns related to decision actions.

Decisions are not necessarily easy to separate into a planning and an execution phase and the decision-making process can often be reflected in the movement associated with the decision. Here, we used formalized definitions of concepts relevant in decision-making and learning to explore if and how these concepts correlate with decision-related movement paths, both during and after a choice is made. To this end, we let 120 participants (46 males, mean age = 24.5years) undergo a repeated probabilistic two-choice task with changing probabilities where we used mouse-tracking, a simple non-invasive technique, to study the movements related to decisions. The decisions of the participants were modelled using Bayesian inference which enabled the computation of variables related to decision-making and learning. Analyses of the movement during the decision showed effects of relevant decision variables, such as confidence, on aspects related to, for instance, timing and pausing, range of movement and deviation from the shortest distance. For the movements after a decision there were some effects of relevant learning variables, mainly related to timing and speed. We believe our findings can be of interest for researchers within several fields, spanning from social learning to experimental methods and human-machine/robot interaction.

Monitoring wildlife abundance through track surveys: A capture-mark-recapture inspired approach to assess track detection by certified trackers in the Kalahari, Botswana

The surveying of animal tracks is a cost-effective wildlife monitoring technique in conservation, provided the substrate is suitable for tracks to imprint and observers are skilled enough to detect and identify them. However, as with every method quantifying population abundance, it can be biased if track detectability is not accounted for. Track detectability has two components: probability p1ˆ for an animal movement path to intersect with the sampling unit at least once and probability p2ˆ of track detection. Here, we measured p2ˆ, often overlooked, and tested to what extent it is affected by observers and sampling conditions, by applying a capture-mark-recapture approach to a driven track survey of 12 wildlife species in the Kalahari, Botswana. We also characterized and quantified disagreements between pairs of observers on the identification and ageing of tracks. Except for fresh (≤24 old) tracks being slightly more detectable (p2ˆ= 0.77 vs 0.61) and reliably identified (probability of agreement in species identification = 0.92 vs 0.87) than older tracks, we demonstrated that p2ˆ is high and most importantly largely constant across sampling conditions and highly skilled observer pairs. Species identification mismatches between observer pairs were rare (8% for fresh tracks) and limited to specific couples of close species, materializing into confusion rather than directional bias. Where p1ˆ can be accounted for in the derivation of population abundance from track counts (e.g. Formozov–Malyshev–Pereleshin formula), our results relative to p2ˆ validate the use of track surveys for wildlife monitoring in the Kalahari. Our conclusion is potentially applicable to a large range of environments across the globe, especially where observer skills are present among local communities, and conservation can benefit both wildlife and people, fostering their coexistence.

Analysis of Energy Consumption of Robotic Welding Stations

Analysis of the energy consumption of industrial robots during the implementation of a technological task can increase efficiency and minimize production costs, as well as extend the service life of robots, taking into account the rational use of energy sources. An important challenge in designing sustainable production processes is the selection of energy-saving technological equipment supporting the work of robots. Additionally, optimization of robot program codes, including parameters and robot movement paths, determines the energy efficiency of the robotic station. Welding is one of the most popular areas of process robotization due to its ability to increase production efficiency and improve the quality of part assembly compared to manual work. In these studies, an exemplary process of robotic welding of aluminum alloy parts was designed, analyzed, and optimized with an orientation towards sustainable development guidelines. This work also presents a review of current publications discussing the authors’ contribution to achieving energy efficiency in robotic welding processes. The purpose of this analysis is also to indicate directions for the development of future research work in order to minimize energy consumption in production processes with an appropriate level of product quality and increase production efficiency.

LOCOMOTOR ACTIVITY OF RATS WITH BLAST-INDUCED TRAUMATIC BRAIN INJURY IN A COMPLEX MAZE

Aim – to investigate the peculiarities of rats with blast-induced brain injury movement in the complex maze.Material and methods. The study was carried out on 15 sexually mature Wistar rats. All animals were randomly divided into 3 groups: experimental group (n=5), which was anesthetized and exposed to an air shock wave with an overpressure of 26-36 kPa; sham group (n=5), which was only anesthetized, and intact group (n=5). The study of locomotor activity was performed using a complex maze for 5 consecutive days, starting on the 1st day after the simulation of blast-induced brain injury. The route of rat`s movement through the maze of three groups was graphically depicted and visually analyzed.Results of the study. The complex maze is considered to be complicated due to the presence of a central zone and T-shaped branches to the right and left, ending with feeders. The complication of the situation and task lead to fear with rapid adaptation of healthy rats. However, if the brain functions are impaired, the experimental animal loses its physiological ability to adapt and shows signs of anxiety. The analysis of the images of the movement paths showed that on the 1st day of training, the rats of the experimental group moved more actively, despite the fact that the animals did not yet know that food was waiting for them. They performed monotonous movements and went to the side sectors more often. On 2nd day, the experimental rats were more active and explored the maze more stereotypically than intact animals. On 3rd and 4th days, clear signs of spatial memory impairment in the experimental group were found in terms of lengthening the path to the feeder. On the 5th day, it was found that the experimental rats were still poorly oriented in the maze, with a monotonous examination of the side sectors.Conclusions. Thus, mild blast-induced traumatic brain injury leads to persistent impairment of spatial memory, as well as behavioral disorders in the form of anxiety. The rats of the experimental group demonstrated stereotypical locomotor activity, as evidenced by the examination of the lateral sectors of the complex maze. At the same time, the memory for food reinforcement was well developed and retained.

Evaluation of joint kinematics in patients with condylar reconstruction using mandibular motion simulation based on intraoral scanning registration.

To summarize the features of condylar kinematics in patients with condylar reconstruction using a mandibular motion simulation method based on intraoral scanning registration. Patients undergoing unilateral segmental mandibulectomy and autogenous bone reconstruction as well as healthy volunteers were enrolled in the study. Patients were grouped based on whether the condyles were reconstructed. Mandibular movements were recorded using a jaw tracking system, and kinematic models were simulated after registration. The path inclination of the condyle point, margin of border movement, deviation, and chewing cycle were analyzed. A t test and one-way analysis of variance (ANOVA) were carried out. A total of 20 patients, including 6 with condylar reconstruction and 14 with condylar preservation as well as 10 healthy volunteers were included. The patients with condylar reconstruction showed flatter movement paths of the condyle points. The mean inclination angle of the condylar movement paths of the patients with condylar reconstruction (0.57 ± 12.54 degrees) was significantly smaller than that of those with condylar preservation (24.70 ± 3.90 degrees, P = 0.014) during both maximum opening and protrusion (7.04 ± 12.21 degrees and 31.12 ± 6.79 degrees, respectively, P = 0.022). The inclination angle of the condylar movement paths of the healthy volunteers was 16.81 ± 3.97 degrees during maximum opening and 21.54 ± 2.80 degrees during protrusion; no significant difference compared with the patients. The condyles of the affected side tended to deviate laterally in all patients during mouth opening and protrusion. Patients with condylar reconstruction showed more severe symptoms of mouth opening limitation and mandibular movement deviation as well as shorter chewing cycles than patients with condylar preservation. Patients with condylar reconstruction showed flatter movement paths of the condyle points, greater lateral motion range, and shorter chewing cycles than those with condylar preservation. The method of mandibular motion simulation based on intraoral scanning registration was feasible to simulate condylar movement.

Learning and generalization of task-parameterized skills through few human demonstrations

In the field of robotics, the demand for adaptable skills capable of effectively handling diverse situations has surpassed the reliance on repetitive tasks. To enhance the generalization of motion policies, task-parameterized learning has emerged as a valuable approach, as it encodes pertinent contextual information in task parameters, facilitating the flexible execution of tasks. This process requires the collection of multiple demonstrations in various situations. Generate a set of diverse situations covering all possible cases is a complex task. Due to this, the search for training with fewer demonstrations becomes highly desirable. In this article, we present a novel algorithm focused on generating synthetic information to facilitate the generalization of parameterized tasks. This algorithm makes use of Kinesthetic Fast Marching Learning, a Learning from Demonstration (LfD) algorithm that allows obtaining optimal movement paths based on velocity fields. The algorithm enables autonomous data generation, producing demonstrations that are equal to or more optimal than those generated by users themselves. Evaluation is done through a metric based on Wasserstein distance that takes into account the probabilistic data of the generated paths. The algorithm has been evaluated through tests in simulated environments, comparing its efficiency against two widely used algorithms (where it has shown greater efficiency in generalization and the generation of more optimal paths) and with real-world tests in a task-oriented environment (sweeping) carried out by the ADAM robot.

Emergency fire evacuation simulation of underground commercial street

High-density built-up areas in cities often enlist the underground realm to provide solution space for transport, shopping and other purposes. The special location, layout, and accessibility of underground structures often generate unique and acute safety-risk concerns. They are inadequately understood and managed and cannot be tackled appropriately by conventional risk assessment and abatement methods. This study focused on evacuating underground commercial streets (UCS) with a heavy concentration of people in Fuzhou city in China. Despite the widespread use of building information modeling (BIM) in construction, it has rarely been applied to studies of underground shopping streets. This study adopted BIM technology as the core method, in conjunction with PyroSim fire and Pathfinder evacuation simulation software. Different fire scenarios in four fire protection zones and the most unfavorable fire sources were set in the model. Based on a calculated number of persons at the start of a fire, different movement paths, stair configuration and exit width were simulated. The choice of escape routes, congestion locations, and slack time windows were identified by the graphical images of the simulation programs. Required safe egress time was compared with available safe egress time, and the number of successful evacuees was reckoned. The effects of three escape-stair forms on evacuee utilization and evacuation rates were evaluated. Their evacuation efficiency was ranked: crossed stair > straight stair > parallel-double stair. The simulation results can optimize building layout design and improve understanding of evacuation-efficiency factors. The findings can contribute to reducing casualties and property losses and improving UCS's fire safety management.

Distributed short-term predictive control for AUV clusters in underwater cooperative hunting tasks

A distributed short-term predictive control method is proposed to be applied to autonomous underwater vehicle (AUV) clusters for underwater cooperative hunting tasks. To support AUV clusters in unknown underwater dynamic environments, the constraints of information acquisition, AUV motion constraints, collision avoidance, and smoothness requirements of motion paths in the tasks are considered. First, a distributed multi-constraint optimization model including target attraction, interactions between AUVs, continuous obstacle avoidance, and control effort is proposed. Effective information between AUVs is extended under limited information conditions. Second, each AUV solves the distributed optimization problem and determines the desired trajectory in real time using information from the prediction horizon. In the simulation experiments, the proposed method is demonstrated to provide at least 12.19%, 11.08%, and 79.89% improvement in terms of task completion time, energy consumption, and path smoothing, respectively, when compared to other methods under the same information conditions. The robustness of the proposed method under different noise conditions is verified by positioning noise experiments, and the task can still be accomplished even if the noise level reaches 75% of the safe distance. The adaptability of the proposed method is demonstrated by simulations in different environments.

A mobile node path optimization approach based on Q-learning to defend against cascading failures on static-mobile networks

The research on cascading failures in static networks has become relatively mature, and an increasing number of scholars have started to explore the network scenarios where mobile nodes and static nodes coexist. In order to enhance the resilience of static-mobile networks against cascading failures, an algorithm based on Q-learning for optimizing the path of the mobile node is proposed in this paper. This paper proposes a Q-learning-based algorithm for optimizing the path of the mobile node. To achieve this objective, a cascading failure model is established based on sequential interactions between mobile nodes and static nodes in this study. In this model, the motion paths of the mobile node are generated by the Q-learning algorithm. Based on this approach, extensive experiments are conducted, and the results demonstrate the following findings: 1) By increasing the adjustable load parameters of static nodes in the network, the occurrence of cascading failures is delayed, and the frequency of cascading failures is decreased. 2) Increasing the adjustable load parameter, capacity parameter, and network size of static nodes contributes to the network's resilience against cascading failures. 3) As the communication radius of the mobile node increases, the scale of failures in the static network initially increases and then decreases. 4) Different trajectories of the mobile node have a significant impact on network robustness, and paths generated based on Q-learning algorithm exhibit significantly improved network robustness compared to Gaussian-Markov mobility trajectories. The Q-learning algorithm is compared to the Ant Colony Optimization algorithm in terms of execution time, path length, and network robustness, and the Q-learning algorithm demonstrating favorable performance. These experimental results can be valuable for theoretical research on cascading failures in static-mobile networks.

The influence of imbalances on the dynamic characteristics of the laboratory centrifuge HERMLE Z306

Laboratory centrifuges are used in various industries. During operation, vibrations occur that lead to resonant frequencies, which in turn impair functionality. This paper presents an overview of the computational model of the HERMLE Z306 laboratory centrifuge used in medical laboratories to separate mixtures of different fractions to determine the dynamic characteristics. The zones of stable operation of the centrifuge and the influence of the rotation speed on the natural frequencies are analytically determined. Experimental results are presented with the influence of imbalances on the dynamic characteristics of the HERMLE Z306 centrifuge. As a result of the modeling, the amplitude-frequency characteristics are determined and a Campbell diagram is constructed. Objective: Modeling of dynamic processes in laboratory centrifuges by studying the influence of imbalances on the quality of mixture separation. Determination of zones of stable operation of the centrifuge.Purpose: Construction of amplitude-frequency characteristics of the centrifuge, determination of zones of stable operation of the laboratory centrifuge during separation and Campbell diagram showing the dependence of natural frequencies on the rotation speed of the HERMLE Z306 centrifuge. This diagram makes it possible to determine the resonance zones. Methods of implementation: Based on the use of the Lagrange equation of the second kind, a model is obtained that makes it possible to determine the zones of stable operation of the centrifuge. Using experimental equipment, determine the frequency response of the centrifuge and analyze the Campbell diagram to determine the resonance zones.Results: The zones of stable operation of a laboratory centrifuge were analytically determined. The amplitude-frequency characteristics of the HERMLE Z306 centrifuge were constructed, the trajectories of the free end of the shaft were built taking into account the corresponding imbalances, and the resonance zones were experimentally determined. Conclusions: Experimental studies have shown that the free end of a laboratory centrifuge shaft moves along a surface whose shape and, accordingly, the path of movement depend on both the angles of rotation and translational movement that arise as a result of deformations of elastic supports. The analytical and experimental studies made it possible to identify unstable modes and thereby determine the areas of the centrifuge's operating modes. The separation process will be stable if the roots of the equation have a negative real part, and moreover, the motion will be asymptotically stable in the presence of resistance forces. An experimental technique for determining the dynamic parameters of the centrifuge has been developed. On its basis, the effect of the rotation speed on the natural frequencies was determined.

Quantifying coordinative patterns in steady‐state running: The impact of footwear and foot strike on joint coupling variability

AbstractIn this study, we aimed to compare and contrast the intralimb coordinative patterns of habitual forefoot strikers (FFS) and rearfoot strikers (RFS) during steady‐state running across three different shoe types: minimalist, neutral and cushioned shoes. To describe these coordinative patterns, we implemented the concept of the ‘preferred movement path’ which represents the movement path that runners naturally select in response to their physical capacity and external environment. We quantified cycle‐to‐cycle consistency (ACC) and within‐trial variance in coordination patterns (SoV) using joint angle data from the ankle and knee for ankle‐knee coupling and from the knee and hip for knee‐hip coupling. Additionally, we calculated the measure of shape difference in joint coupling as the sum of squared distances (SSD) between/within conditions and groups. The percentage of runners who displayed shape differences below certain SSD thresholds was also evaluated. Our findings revealed no significant group or shoe type effect on any of the variability measures (ACC: p = 0.460 for ankle‐knee and p = 0.832 for knee‐hip; SoV: p = 0.345 for ankle‐knee and p = 0.755 for knee‐hip). However, there was a significant (p < 0.001) shape difference observed between the most extreme shoe conditions. Despite this, when runners switched shoes, 70%–90% of them maintained their original coordinative pattern across both joint couplings, indicating a strong adherence to their preferred movement path. This suggests that while shoe type can influence the shape of the coordinative pattern, the inherent movement tendencies of the runners remain largely consistent.

Adaptive Network Model for Assisting People with Disabilities through Crowd Monitoring and Control.

Here, we present an effective application of adaptive cooperative networks, namely assisting disables in navigating in a crowd in a pandemic or emergency situation. To achieve this, we model crowd movement and introduce a cooperative learning approach to enable cooperation and self-organization of the crowd members with impaired health or on wheelchairs to ensure their safe movement in the crowd. Here, it is assumed that the movement path and the varying locations of the other crowd members can be estimated by each agent. Therefore, the network nodes (agents) should continuously reorganize themselves by varying their speeds and distances from each other, from the surrounding walls, and from obstacles within a predefined limit. It is also demonstrated how the available wireless trackers such as AirTags can be used for this purpose. The model effectiveness is examined with respect to the real-time changes in environmental parameters and its efficacy is verified.

Virtual tactile POMDP-based path planning for object localization and grasping

Tactile sensation endows humans with the capacity to localize objects, which is also significant for robots. However, it is challenging for robots to localize and grasp objects only by tactile sensation. One potential snag is that tactile sensors do not provide feedback without external contact, which means the robot cannot spontaneously plan its path. To address this issue, we propose a novel Virtual Tactile POMDP (VT-POMDP)-based method for object localization and grasping in a 3D workspace, which models the path planning problem as the VT-POMDP to plan the motion path of the grasper. The state space and action space in the VT-POMDP are classified into seven categories to reduce the spatial dimension and the computational cost of path planning. Furthermore, we model the motion scale of the grasper using a variable-scale moving strategy to improve the efficiency of object localization. Finally, we verify the effectiveness and generalization of the method through a series of simulation experiments and real-world experiments.

The impact of movement path of sesame seeds (Sesamum indicum L.) during treatment with intense pulsed light (IPL) using a continuous pilot-scale device on the reduction of indigenous microorganisms.

The objective of this study was to enhance the microbial inactivation efficacy of sesame seeds through the utilization of a pilot-scale IPL device, while also identifying the process variables that influence the microbial inactivation effect. Three different types of IPL processes were employed, each with a distinct arrangement, to treat sesame seeds. The total fluences applied ranged from 1.33 to 53.94J/cm2. Total aerobic bacteria and fungi exhibited a maximum reduction of 2.27 and 2.77 log, respectively. The curved pathway of the sample flow effectively extended the duration of exposure to the IPL emitted by the lamps. The arrangement of the IPL process using two lamps in parallel but at different locations proved the most efficient for microbial inactivation. The application of IPL was found to be effective in reducing the presence of indigenous microbes in sesame seeds while having no significant impact on the physicochemical properties of the seeds.

Chinese Buddhism in the System of Worlds of Mahayana Buddhism

The research examines the features of the Mahayana world of Chinese Buddhism in the system of worlds of Mahayana Buddhism. A definition is given of the concept of “worlds of Mahayana Buddhism” as divergent constructs formed in the areas of distribution of Buddhism, as well as the world of Chinese Mahayana Buddhism. The specific features of Mahayana Buddhism in China, formed as a result of its assimilation on traditional religious and sociocultural grounds, are shown. The factors that prevented the entry of Buddhism into the civilizational space of China and determined its formation there over the course of several centuries are indicated. The role of the Prajnaparamita texts, the Lotus Sutra, the Nirvana Sutra and the Avatamsaka Sutra in the formation of schools of Chinese Buddhism is revealed. The role of the Mahaparinirvana Sutra in the formation of the idea of an instant path to salvation in China is especially emphasized. The importance of the idea of an instant way of salvation for the formation of Chinese schools itself is shown. An analysis is given of the formation of the philosophical and soteriological direction in China, which took a different direction than in India, where the development of Madhyamaka ideas led to an emphasis on the epistemological aspects of the doctrine of emptiness, while in China attention was focused on its ontological aspects. The significance of the problem of truly existing is indicated as one of the main problems of philosophical research of the Tiantai, Chan, Huayan schools of Chinese Buddhism, as well as the idea of instantly achieving Buddhahood, which became the main soteriological guideline of these schools. It is indicated that in Tibet the development of philosophical and soteriological directions was developed in line with Indian Buddhism. The reasons for the Tibetans' choice of the soteriological path of the gradual movement of nirvana, which determined the development of Buddhism in their country, are considered. The role of Atisha in choosing the gradual path to nirvana is revealed. The difference between the worlds of Mahayana Buddhism, formed in China and Tibet, is shown.