Cooperative control of multiple heavy-haul trains can improve the safety and efficiency railway transportation. However, influence internal external unknown disturbances for is a serious obstacle, which will lead to imprecise train operation control. To address this issue, cooperative active disturbance rejection proposed. First, multi-mass point longitudinal dynamic model established meet actual operation. Second, controller designed estimate compensate caused by interaction between...

The Yuanba Gasfield is a large gas field discovered by Sinopec in the Sichuan Basin recent years, and another main exploration area for natural reserves production increase after Puguang Gasfield. ultra-deep sour reservoir characterized complicated geologic structure, deep reservoirs complex drilled formation, especially continental strata which are highly abrasive with low ROP (rate of penetration) long drilling period. After many years practice technical research, following six key...

The potential of heavy-haul train platoon operation technology in improving railway freight capacity is increasingly recognised, with extensive trial research currently underway. This study firstly utilising longitudinal dynamics devised a space–time collaborative collision avoidance model for trainsets, accounting air brake delay. Secondly, an application strategy was proposed, focusing on and managing speeds steep ramps. Subsequently, constraint-driven optimal control scheme tailored...

The bacterial foraging optimization algorithm (BFOA) is an intelligent population widely used in collision avoidance problems; however, the BFOA inappropriate for ship planning with high safety requirements because converges slowly, optimizes inaccurately, and has low stability. To fix above shortcomings of BFOA, autonomous based on improved (IBFOA) demonstrated this paper. An adaptive diminishing fractal dimension chemotactic step length designed to replace fixed achieve adjustment, optimal...

The macroinvertebrate communities and relationships with environmental variables were characterized in the Erhai basin by sampling at 44 sites. Among 76 taxa observed, Baetis sp., Tubificidae, Simulium Eukiefferiella Gammarus sp. Parakiefferiella dominant taxa. Canonical correspondence analysis indicated that seven variables, namely altitude, Ca2+, chemical oxygen demand, NO3–N, total phosphorus, streambed width, a qualitative habitat evaluation index (QHEI), significantly related to...

The relationships between temporal patterns of macroinvertebrate community and water physicochemical parameters were investigated in the Xiangxi River, which is largest tributary to Three Gorges Reservoir (TGR) Hubei province, China. construction TGR has strongly impacted River watershed, but inter-annual stream communities have not been examined. We sampled macroinvertebrates monthly from 2004 2006. assessed persistence (similarity years species assemblage) stability with respect relative...

Feeding strategies are traits that reflect the adaptation of a species to environmental conditions. Macroinvertebrates an important primary consumer in stream food webs, but abiotic and biotic drivers functional feeding groups (FFGs), which categorized based on strategies, require additional clarification. The aim our study was quantify contributions factors (water quality land use at different scales) (important producers, such as epilithic diatoms) variation FFGs macroinvertebrates Jinshui...

Understanding the driving mechanisms of diversity across multiple dimensions is a fundamental task in biodiversity conservation. Here, we examined alpha and beta macroinvertebrates taxonomic, functional, phylogenetic mountain streams northwestern Hubei Province, China. We also assessed how much local environmental, land use, climatic, spatial variables affected these diversities. found that (1) there were generally weak or no correlations between dimensions; (2) compared to both functional...

Abstract Periphyton acts as an important primary producer in stream food webs with bottom-up grazing pressure and is also subject to effects of top-down pressure. However, the underlying mechanisms these interactions remain unclear. In this study we conducted a mesocosm experiment explore periphyton response by freshwater snail Bellamya aeruginosa relation quality indicated polyunsaturated fatty acid (PUFA) biomarkers, including eicosapentaenoic (20:5n3) 22C docosahexaenoic (22:6n3), which...

Abstract RamRig hosting system is a common for offshore and onshore drilling rigs, which uses ram cylinders to lift lower the top drive on rig. In order ensure accuracy, stability robustness of synchronous control system, RBF neural network used adjust PID parameters online, three loop simulation model based optimized controller built in AMESim Simulink. The results show that hydraulic circuit has higher accuracy stability, fully capable realizing output action system.