automatic regulation
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2021 ◽  
Vol 80 (6) ◽  
pp. 343-350
Author(s):  
V. A. Nikonov ◽  
V. F. Zubkov ◽  
M. N. Tsibizov ◽  
I. V. Nazarov ◽  
D. V. Gorskiy

The article discusses technical solutions for the creation of an effective design of a brake system for high-speed longwheelbase platforms intended for the transport of containers, as well as for the development of a fundamentally new brake equipment for the pneumatic, electro-pneumatic and mechanical parts of the brake system. Modular braking equipment for the pneumatic and electro-pneumatic parts of the high-speed platform braking system, compactly located under the platform frame, provides technical compatibility when controlling platform brakes as part of not only a high-speed freight train of permanent formation, but also in trains for other purposes, regardless of the location of the platform in the composition of the train. The performance of the braking equipment of each platform in motion and in the parking lot is monitored using pressure sensors and an electronic unit that processes the readings of the sensors and transmits information to the locomotive via one of the wire lines of the electro-pneumatic brake. The brake rigging used on the high-speed platform is arranged in the design of three-axle bogies and provides doublesided pressing on the wheels with typical composite brake pads, automatic regulation and maintenance of the standard clearances between brake pads and wheels. The proposed promising technical solutions make it possible to continuously diagnose the parameters of the brakes of each platform as part of a permanent train, display them on the locomotive monitor and transmit them to the dispatch centers of the Russian Railways infrastructure. Thanks to this, the braking effciency can be increased and the safety of train traffc can be ensured while increasing the permissible travel speeds. In the modern concept of digitalization of the infrastructure of Russian Railways, which provides for the creation in 2021–2025 (and in the future until 2030) of cars in which intelligent technologies should be applied, the braking system of a high-speed platform can be considered as the basis for creating a digitally controlled train — one of the key elements of the digital railway.


Author(s):  
Serhii Burlaka ◽  
Oleksii Tokarchuk

Ukraine is one of the energy-deficient countries because it covers its needs in fuel and energy resources from domestic reserves by only 53% (imports 75% of the required natural gas and 85% of crude oil and petroleum products). Dependence on oil imports is seen by most developed countries as a matter of national and energy security, and the use of petroleum products as energy sources poses a significant environmental risk. According to the analysis of the state of the world engine industry, the most effective measures to improve the design of the engine are: development and implementation of a new workflow with effective methods of mixing and combustion; development and creation of the design of the system of automatic regulation of diesel rotation. frequency to improve fuel economy And to reduce toxicity in partial load mode, some cylinders are switched off at idle. To strengthen the requirements for fuel consumption standards and the level of toxicity of exhaust gases, as well as to increase the reliability and efficiency of agricultural power engines, it is necessary to formulate measures to improve its design. The choice of a fuel should be determined by the optimal combination of environmental and economic performance of the engine. Prospects for the use of a particular fuel of plant origin are noted. If for fuels of petroleum origin the improvement of its properties is determined by special processing, then oils with the set characteristics can be received already in "field" by selection of the corresponding grades of plants, use of fertilizers, agronomic actions, etc. The problem of reducing the consumption of diesel fuel at idle and low load can be solved by excluding from its operation part of the cylinders (this method is widely used) and closing the cycle of one cylinder. A comparative analysis of the main technical and environmental performance of the D-240 diesel engine when working on traditional and alternative fuels using the computer program Diesel-RK.


Author(s):  
Ping Shi ◽  
Anan Li ◽  
Liang Wu ◽  
Hongliu Yu

Abstract Objective: Heart rate asymmetry (HRA) is an approach for quantitatively assessing the uneven distribution of heart rate accelerations and decelerations for sinus rhythm. We aimed to investigate whether automatic regulation led to HRA alternation during passive lower limb training. Methods: Thirty healthy participants were recruited in this study. The protocol included a baseline (Pre-E) and three passive lower limb training trials (E1, E2 and E3) with a randomized order. Several variance-based HRA variables were established. Heart rate variability (HRV) parameters, i.e., mean RR, SDNN, RMSSD, LF (n.u.), HF (n.u.) and VLF (ms2), and HRA variables, i.e., SD1a, SD1d, SD2a, SD2d, SDNNa and SDNNd, were calculated by using 5-min RR time series, as well as the normalized HRA variables, i.e., C1a, C1d, C2a, C2d, Ca and Cd. Results: Our results showed that the performance of HRA was distinguished. The normalized HRA was observed with significant changes in E1, E2 and E3 compared to Pre -E. Moreover, parts of non-normalized HRA variables correlated with HRV parameters, which indicated that HRA might benefit in assessing cardiovascular modulation in passive lower limb training. Conclusions: In summary, this study suggested that passive training led to significant HRA alternation and the application of HRA gave us the possibility for autonomic assessment.


2021 ◽  
Vol 937 (3) ◽  
pp. 032045
Author(s):  
B Kalmykov

Abstract The article deals with the problem of improving the drive of the driving wheels and working bodies of agricultural machines. The analysis of works on the research topic showed that this problem is solved by giving the very executive mechanisms of the agricultural machine the ability to adjust the characteristics in the direction that improves certain indicators of the quality of functioning, by the purpose of which it is possible to judge the efficiency of the operation of such a machine. The flexibility of the structure can only be ensured by the presence of additional degrees of mobility. Therefore, it is proposed to use differential mechanisms of varying complexity in the drive, which will provide continuous automatic regulation of its own operating parameters depending on changes in the resistance of the working medium to the executive bodies of the machine.


2021 ◽  
Vol 8 ◽  
Author(s):  
Qing Feng ◽  
Meilin Ai ◽  
Li Huang ◽  
Qianyi Peng ◽  
Yuhang Ai ◽  
...  

Background: Septic shock patients have tendencies toward impairment in cerebral autoregulation and imbalanced cerebral oxygen metabolism. Tissue Oxygen Saturation (StO2) and Transcranial Doppler (TCD) monitoring were undertaken to observe the variations of cerebral hemodynamic indices and cerebral/peripheral StO2 to find risk factors that increase the sepsis-associated delirium (SAD).Materials and Methods: The research cohort was chosen from septic shock patients received in the Department of Critical Care Medicine, Xiangya Hospital, Central South University between May 2018 and March 2019. These patients were separated into two groups, SAD and non-SAD as assessed by using the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU). Comparisons were made between the two groups in terms of peripheral StO2, fluctuations in regional cerebral oxygen saturation (rSO2), cerebral vascular automatic regulation function [Transient Hyperemic Response Ratio (THRR) index], cerebral hemodynamic index, organ function indicators, blood gas analysis indices, and patient characteristics.Results: About 39% of the patients (20/51) suffered from SAD. Nearly 43% of the patients died within 28 days of admission (22/51). Individuals in the SAD cohort needed a longer period of mechanical ventilation [5 (95% CI 2, 6) vs. 1 days (95% CI 1, 4), p = 0.015] and more time in ICU [9 (95% CI 5, 20) vs. 5 days (95% CI 3, 9), p = 0.042]; they also experienced more deaths over the 28-day period (65 vs. 29%, p = 0.011). The multivariate regression analysis indicated that independent variables associated with SAD were THRR index [odds ratio (OR) = 5.770, 95% CI: 1.222–27.255; p = 0.027] and the mean value for rSO2 was < 55% (OR = 3.864, 95% CI: 1.026–14.550; p = 0.046).Conclusion: Independent risk factors for SAD were mean cerebral oxygen saturation below 55% and cerebrovascular dysregulation (THRR < 1.09).


Water ◽  
2021 ◽  
Vol 13 (22) ◽  
pp. 3160
Author(s):  
Isabel Echeverribar ◽  
Pablo Vallés ◽  
Juan Mairal ◽  
Pilar García-Navarro

The vast majority of reservoirs, although built for irrigation and water supply purposes, are also used as regulation tools during floods in river basins. Thus, the selection of the most suitable model when facing the simulation of a flood wave in a combination of river reach and reservoir is not direct and frequently some analysis of the proper system of equations and the number of solved flow velocity components is needed. In this work, a stretch of the Ebro River (Spain), which is the biggest river in Spain, is simulated solving the Shallow Water Equations (SWE). The simulation model covers the area of river between the city of Zaragoza and the Mequinenza dam. The domain encompasses 721.92 km2 with 221 km of river bed, of which the last 75 km belong to the Mequinenza reservoir. The results obtained from a one-dimensional (1D) model are validated comparing with those provided by a two-dimensional (2D) model based on the same numerical scheme and with measurements. The 1D modelling loses the detail of the floodplain, but nevertheless the computational consumption is much lower compared to the 2D model with a permissible loss of accuracy. Additionally, the particular nature of this reservoir might turn the 1D model into a more suitable option. An alternative technique is applied in order to model the reservoir globally by means of a volume balance (0D) model, coupled to the 1D model of the river (1D-0D model). The results obtained are similar to those provided by the full 1D model with an improvement on computational time. Finally, an automatic regulation is implemented by means of a Proportional-Integral-Derivative (PID) algorithm and tested in both the full 1D model and the 1D-0D model. The results show that the coupled model behaves correctly even when controlled by the automatic algorithm.


2021 ◽  
Vol 2091 (1) ◽  
pp. 012019
Author(s):  
N M Zhilo ◽  
E L Litinskaia ◽  
N A Bazaev

Abstract Kidney failure leads to the serious health issues associated with abnormal water-salt balance. In this case, peritoneal dialysis therapy is often prescribed: 1-2 liters of dialysis solution is administered in peritoneal cavity for 3-4 hours. During this time, due to diffusion and osmosis, toxins and excess water are transferred from blood to solution. One of the method’s downsides is the transition of glucose (osmotic agent) into the bloodstream, which leads to a gradual decrease in the fluid removal rate. To mitigate this problem, one must use the system, which will measure current glucose concentration and inject glucose into solution to compensate absorption. The paper proposes such a control system for automatic regulation of the glucose concentration in peritoneal dialysate solution. Its structure, elements, their functions and characteristics are discussed. Proposed system is capable to work autonomously or can be incorporated into wearable “artificial kidney” device.


2021 ◽  
Vol 2094 (4) ◽  
pp. 042036
Author(s):  
A V Shukalov ◽  
D A Zakoldaev ◽  
I O Zharinov ◽  
O O Zharinov

Abstract The cyber-physical production base technologies are control, computing and connection being applied altogether in the industrial object technological processes automatic regulation systems. They use control technologies in multi-loops and multi-channel regulation systems forming a hierarchy structure. Automatics functional elements unite in the intermediary regulation scheme stabilizing hierarchy control objects, which states are detected with sensors. Computing technologies are used in the cyber-physical production imitation virtual environment and provide processes simulation based on control models and cyber-physical systems digital twins structured in hierarchy levels. The regulation accuracy increase is provided with physical and model processes results comparison detecting non-definition factors acting production processes accuracy. The communication technology is used for the cyber-physical systems net information exchange given with the Internet of Things parameters. The cyber-physical systems continuous work in the non-ideal communication net regulation interval is provided with preventive control signals compensating operation and information delay of automatic conveyor lines. There is a scheme given of multi-loop and multi-channel automatic cyber-physical production using control objects hierarchy based on cyber-physical systems hierarchy and item manufacturing technological tasks.


2021 ◽  
Vol 2076 (1) ◽  
pp. 012013
Author(s):  
Junfeng Zhu ◽  
Xingtian Wang ◽  
Wenbing Liu ◽  
Shifeng Wang ◽  
Qiujun Wang

Abstract Photovoltaic irrigation has been widely used in many areas without conventional energy sources. In order to solve the problem of unstable operation and poor irrigation uniformity caused by the diurnal variation of solar radiation, a photovoltaic direct-drive water-saving irrigation system with automatic regulation was proposed. By using automatic control technology and the method of zonal rotation irrigation, all the electric energy generated by solar panels can be converted into irrigation energy under different light intensities, so that the water-saving irrigation equipment can work stably in different regions and the irrigation uniformity is ensured in different regions. According to the characteristics of solar energy resources and photovoltaic water-pumping units, the optimum design method of photovoltaic water-saving irrigation system is put forward. The minimum capacity of solar panels can meet the irrigation demand of a certain area, which can guide the engineering design of solar water-saving irrigation, greatly improve the engineering quality and energy utilization rate. It has the advantages of simple design, low cost, stable operation and energy-saving ring.


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