Robust actuator based on photothermally responsive hydrogel with fast recovery capabilityHou, Guodong; Zhang, Feiyu; Qian, Xiaoshi
doi: 10.1088/1742-6596/2491/1/012013pmid: N/A
Propulsion by deformation and oscillation is a familiar law of motion in nature. Often, these motions are signaled and driven by constant external conditions, such as the phototropism of plants. Here, we have prepared a soft photosensitive material utilizing ice templates and cryo-polymerization, which combines light absorbers and thermally responsive hydrogels and thus possesses superb photothermal conversion, mechanical deformation, and fast recovery capabilities. The soft actuator based on this material generates a dynamically balanced oscillation with intermittent shadows creating a continuous self-feedback loop, allowing the actuator to operate continuously and durably under constant illumination. Combining the modules of conjugate heat transfer, non-isothermal flow, and fluid-solid coupling, we have gained a deeper understanding of the interaction of the soft actuator with the temperature and flow fields. In the future, the soft actuator can be widely developed and combined with other conventional drive strategies in an attempt to apply in soft robotics, underwater operations, and other fields.
Identification of Airport Similar Days Based on K-prototype Cluster and Grey Correlation AnalysisZhu, Xuhao; Dong, Xiangning; Wang, Shuce; Zhang, Junrui
doi: 10.1088/1742-6596/2491/1/012003pmid: N/A
Considering similar air traffic control techniques for the present based on close historical dates is a good approach due to the unpredictability of weather and air traffic, as well as to increase controller efficiency. A K-prototype clustering technique and grey correlation analysis are proposed to discover similar days to address the problem of similar identification. Firstly, the weather and air traffic datasets are used to create a set of features broken down into numerical and categorical attributes. Secondly, the historical data are clustered using the K-prototype clustering, which is then paired with grey correlation analysis to identify days similar to the reference day and examine the traffic management initiatives employed on that day. Finally, the research uses actual weather information and aircraft schedules from Nanjing Lukou International Airport as examples. The outcomes demonstrate that the similar days picked by the model are representative and can serve as a foundation for airport controllers' decision-making.
Estimation Distributed Algorithm to Aid Aircraft Runway Scheduling ProblemLiu, Yingli; Hu, Minghua; Su, Jiaming
doi: 10.1088/1742-6596/2491/1/012007pmid: N/A
In this paper, we proposed a runway sequencing and optimal scheduling method. This includes constructing a flight sequencing model to minimize design delay time for arrival and departure flights and designing flight sequencing rules to obtain large-scale feasible runway usage sequences efficiently. Furthermore, a Kendall-τ distance-based Mallows model is constructed based on the obtained flight sequences. An Estimation Distributed Algorithm (EDA) is used to assign each flight a runway usage time that meets the constraint so that the total delay time is minimized. Finally, it is verified that the method can not only reduce the total delay time of the flight as a whole but also has significant performance and is highly implementable through the analysis of calculation cases.
The Design of Dynamic Channelization and Signal Control SystemWang, Yanjun; Wang, Bing
doi: 10.1088/1742-6596/2491/1/012004pmid: N/A
For a long time, the development of urban transportation promotes economic development, however, which brings many urban traffic problems. The significant fluctuation of daily traffic volume has caused serious congestion and queuing at some small or medium-sized intersections. In order to enhance the performance of the, this paper proposes a scheme of dynamic channelization and signal control system which can be adapted to flat and peak. The scheme realizes the conversion of different channelization schemes via LED light strips laid on the road. In order to avoid potential conflicts in the process of scheme transformation, this paper focuses on the transition process from flat peak scheme to peak scheme. This scheme can also realize the systematic adjustment of traffic capacity at intersection, and also has the function of dynamic lane adjustment.
Experimental Research on Vibration Dynamics Performance of Type B Metro VehiclesChen, Guanghu; Gong, Yanqing; Xie, Lei; Liu, A’kui; Chen, Shaoqiang
doi: 10.1088/1742-6596/2491/1/012006pmid: N/A
In recent years, due to the acceleration of urban rail transit construction, the cumulative length of urban rail transit lines in China has also continued to grow. As one of the typical representatives of urban rail transit, the subway is an excellent choice for the general public due to its energy saving, environmental friendliness, large transportation capacity, and high punctuality rate. However, this also imposes stricter requirements on the operational safety and smoothness of subway vehicles. The vibration generated by subway vehicles in operation will affect the riding experience of passengers and subway vehicles to varying degrees. Vibration research is an important part of the research on rail transit vehicles. In this paper, a dynamic performance test of a B-type subway vehicle is carried out. According to GB/T5599-2019 and other standards, the operation safety and stability of the vehicle under no-load and overloaded loads and the vehicle vibration characteristics are studied, which provides reliable experimental data for the subsequent research of the vehicle.
A short-term highway traffic flow forecasting model based on CNN-LSTM with an attention mechanismMa, Feihu; Deng, Shiqi; Mei, Sang
doi: 10.1088/1742-6596/2491/1/012008pmid: N/A
Domestic and foreign scholars have researched traffic flow forecasting and established mature systems; however, these systems are mainly based on normal weather. The influence of weather on traffic flow forecasting is rarely considered in existing studies. Therefore, the correlation between meteorology and traffic flow is analyzed, and an attention mechanism is introduced to improve the ability of the model to extract characteristics of time series data. The results show that the model proposed in this paper is better than other models and the traffic flow forecast using meteorological data is more accurate when an attention mechanism is added.
Runoff prediction based on a VMD-LSTM model considering the decomposition errorMa, Ya-Rong; Yang, Jing; Li, Hao; Liao, He; Feng, Yu-Xin
doi: 10.1088/1742-6596/2491/1/012017pmid: N/A
For increasing the forecasting accuracy of runoff, a combined prediction model composed of the variational mode decomposition (VMD) and long short-term memory network (LSTM) is investigated in our manuscript. Firstly, data from the runoff is decomposed into three modal components via the VMD algorithm, for reducing the complexity of the original data. In addition, decomposition error is also been considered in this paper, and the hidden information in the series is extracted. Three subsequences and the decomposition error are handled by the LSTM method, respectively. Superimposing the prediction results, the prediction result of the runoff is thus derived. Experimental analysis is carried out, and a comparison of the VMD-LSTM model and other algorithmic indicates that the model constructed in our manuscript is more valid for predicting the runoff.
The Investigation of the Mixture Formation and Combustion Characteristic of the Spray-wall ImpingementLi, Jingyuan; Wang, Xiaoyang; Yu, Hanzhengnan; Liu, Yu; An, Xiaopan; Ma, Kunqi; Liang, Yongkai; Xu, Hang; Zhang, Hao
doi: 10.1088/1742-6596/2491/1/012025pmid: N/A
In recent years, investigations into the formation of mixture or combustion characteristics of diesel spray-wall impingement have been summarized. On one hand, the air entrainment strength and fuel concentration distribution in the near-wall area during the spray-wall collision process have been studied. On the other hand, the combustion characteristics of the impinged spray, including ignition and combustion characteristics, have also been discussed. Additionally, the effect of impingement between spray and wall on real diesel engines’ operating condition has been analyzed and summarized. Results showed that increasing the pressure of the injection and shortening the collision distance could enhance the air entrainment strength of spray-wall impingement. Moreover, increasing the injection pressure, shortening the impingement distance, decreasing the environmental pressure, increasing the wall temperature, and reducing the nozzle diameter all improved the mixture formation. Conversely, reducing the environmental temperature, decreasing the nozzle diameter, and increasing the impingement distance all reduced the concentration of soot, and even achieved no soot formation. Under real diesel engine operation conditions, some of the soot formed in the spray-wall collision and deposited on the wall. The structure of these deposits was mainly a simple cluster structure composed of several basic particles, and the porous structure of the deposits was conducive to the oxidation of soot and reduced the deposition rate.
Simultaneous analysis of supercritical carbon dioxide power cycle coupling zeotropic organic Rankine cycle with composition-adjustment and dual-pressure evaporationHuang, Renlong; Chen, Chaoda; Wang, Yage; Zhong, Tianming
doi: 10.1088/1742-6596/2491/1/012029pmid: N/A
A novel cycle is established about the supercritical carbon dioxide power cycle (S-CO2) and the zeotropic organic Rankine cycle (ORC). The thermal efficiency of S-CO2 is superior to the steam Rankine cycle. However, the waste heat released from the expander is not well utilized. The zeotropic ORC with dual-pressure evaporation is considered to be one of the most promising cycles for recovering waste heat. Dual-pressure evaporation of ORC can improve the phase change heat transfer matching in the evaporation section, thus improving the energy conversion efficiency. If the composition of the zeotropic mixture can be adjusted during the dual-pressure evaporation process, the system power performance can be further improved. The supercritical carbon dioxide power cycle coupling the zeotropic organic Rankine cycle with composition adjustment and dual-pressure evaporation (S-CO2/ORC) is proposed for energy utilization efficiency. The influence of different working fluids and exergy destruction analysis is carried out for S-CO2/ORC. The results show that the net power output of the system is the largest, which is 359.79 kW, when R245fa-R236ea is used as the working fluid for the ORC. The analysis of the exergy destruction of S-CO2/ORC using R245fa-R236ea shows that the S-CO2 system accounted for the largest exergy destructions.
Research on Energy-saving Calculation of Navigational Lighting System Powered by Low Current in Green AirportMa, Xiaodan; Li, Tuo; Chen, Fei; Zhang, Lihua
doi: 10.1088/1742-6596/2491/1/012015pmid: N/A
The airport navigation lighting system is an important energy-consuming system in the flight area. The annual energy consumption of large and medium-sized airports can reach millions of kilowatt hours. At present, the airport is replacing traditional halogen lamps with LED navigation lighting for energy conservation. For LED lighting under the traditional 6.6 A power supply system, the circuit loss is high, and the overall energy-saving effect of the system is not good. A low-current power supply energy-saving navigation lighting system is proposed. The primary cable, secondary cable, isolation transformer, and auxiliary lighting system in the navigation lighting circuit are studied by performing the energy-saving calculation of navigation lights under low currents. By building a set of navigation lighting systems to conduct energy consumption experiments and comparing them with theoretical calculations, a calculation model is proposed to provide a basis for energy-saving calculations for the application of a low-current power supply navigation lighting system.