The unreasonable observation arrangements in the satellite operation control center(SOCC)may result in the observation data cannot be downloaded as scheduled.Meanwhile,if the operation instructions released by the sat...The unreasonable observation arrangements in the satellite operation control center(SOCC)may result in the observation data cannot be downloaded as scheduled.Meanwhile,if the operation instructions released by the satellite telemetry tracking center(STTC)for the on-board payloads are not injected on the specific satellites in time,the corresponding satellites cannot perform the observation operations as planned.Therefore,there is an urgent need to design an integrated instruction release,and observation task planning(I-IRO-TP)scheme by efficiently collaborating the SOCC and STTC.Motivated by this fact,we design an interaction mechanism between the SOCC and the STTC,where we first formulate the I-IRO-TP problem as a constraint satisfaction problem aiming at maximizing the number of completed tasks.Furthermore,we propose an interactive imaging task planning algorithm based on the analysis of resource distribution in the STTC during the previous planning periods to preferentially select the observation arcs that not only satisfy the requirements in the observation resource allocation phase but also facilitate the arrangement of measurement and control instruction release.We conduct extensive simulations to demonstrate the effectiveness of the proposed algorithm in terms of the number of completed tasks.展开更多
In recent years, in order to implement the national green development requirements and implement the sustainable development strategy, the traditional wooden formwork and steel pipe scaffold can no longer meet the req...In recent years, in order to implement the national green development requirements and implement the sustainable development strategy, the traditional wooden formwork and steel pipe scaffold can no longer meet the requirements of energy conservation and environmental protection. With the increasingly fierce competition in the housing construction industry, the construction period and cost are continuously reduced. Under the dual pressure of national policy and market environment, the combined construction of aluminum alloy formwork and integrated attached lifting scaffold is timely and shows significant advantages. The combination of the aluminum formwork and the climbing frame is beneficial to the interpenetration of working procedures, the structure, decoration and outdoor works are carried out simultaneously, the construction waste is reduced, the cost of civilized measures is saved, the safety factor of operators is high, the aluminum formwork adopts a quick dismantling system, the construction period is saved, the rigidity of the aluminum formwork is large, the concrete forming quality is good, the turnover times are large, and the recycling value is high.展开更多
This present study is part of the design improvement process of a specified high torque low-speed engine.This work aims at carrying out an in-depth analysis of in-cylinder combustion,mesh sensitivity,and engine perfor...This present study is part of the design improvement process of a specified high torque low-speed engine.This work aims at carrying out an in-depth analysis of in-cylinder combustion,mesh sensitivity,and engine performance at supercharge conditions to provide a foundation for the design improvement process of the given engine.The computational fluid dynamic(CFD)simulations are carried out on a 3D sector from-130°to 130°crank angle(CA)by employing appropriate models to represent the different physical and chemical processes and using the finite volume method for solving the governing differential equations.An extensive investigation has been carried out for the choice of base mesh size and the number of local and temporal refinements to capture the phenomena happening in the combustion chamber at diverse temporal and local scales.The present results have been validated against available literature experimental and simulation results.Primary field variables and the wellknown four phases of combustion have been studied for gaining in-depth insight into these phenomena.Cylinder average pressure,mean temperature,heat release rate(HRR),integrated heat release rate(IHRR),and emissions of CO_(2),CO,NOx,HC and soot are presented to assess the quality of combustion.Engine performance analysis has been done in terms of combustion ef-ficiency,gross work,power,torque,and integrated mean effective pressure(IMEP).The base mesh of 1.4 mm may be an appropriate choice during the injection and combustion process spanning throughout around 40CA from the start of injection while in the remaining simulation duration of around 220CA base mesh of 2 mm gives a sufficient resolution.It has been found that maximum heat release takes place in Phase-III,the mixing-controlled phase,of the combustion process.More than 98%combustion efficiency has been achieved in all the simulations.Around 99%of the total heat release and emissions production takes place within 60CA after top dead center(ATDC).展开更多
基金supported by the Natural Science Foundation of China under Grants U19B2025,62121001,and 62001347in part by Key Research and Development Program of Shaanxi(ProgramNo.2022ZDLGY05-02)in part by Young Talent Support Program of Xi’an Association for Science and Technology(No.095920221337).
文摘The unreasonable observation arrangements in the satellite operation control center(SOCC)may result in the observation data cannot be downloaded as scheduled.Meanwhile,if the operation instructions released by the satellite telemetry tracking center(STTC)for the on-board payloads are not injected on the specific satellites in time,the corresponding satellites cannot perform the observation operations as planned.Therefore,there is an urgent need to design an integrated instruction release,and observation task planning(I-IRO-TP)scheme by efficiently collaborating the SOCC and STTC.Motivated by this fact,we design an interaction mechanism between the SOCC and the STTC,where we first formulate the I-IRO-TP problem as a constraint satisfaction problem aiming at maximizing the number of completed tasks.Furthermore,we propose an interactive imaging task planning algorithm based on the analysis of resource distribution in the STTC during the previous planning periods to preferentially select the observation arcs that not only satisfy the requirements in the observation resource allocation phase but also facilitate the arrangement of measurement and control instruction release.We conduct extensive simulations to demonstrate the effectiveness of the proposed algorithm in terms of the number of completed tasks.
文摘In recent years, in order to implement the national green development requirements and implement the sustainable development strategy, the traditional wooden formwork and steel pipe scaffold can no longer meet the requirements of energy conservation and environmental protection. With the increasingly fierce competition in the housing construction industry, the construction period and cost are continuously reduced. Under the dual pressure of national policy and market environment, the combined construction of aluminum alloy formwork and integrated attached lifting scaffold is timely and shows significant advantages. The combination of the aluminum formwork and the climbing frame is beneficial to the interpenetration of working procedures, the structure, decoration and outdoor works are carried out simultaneously, the construction waste is reduced, the cost of civilized measures is saved, the safety factor of operators is high, the aluminum formwork adopts a quick dismantling system, the construction period is saved, the rigidity of the aluminum formwork is large, the concrete forming quality is good, the turnover times are large, and the recycling value is high.
文摘This present study is part of the design improvement process of a specified high torque low-speed engine.This work aims at carrying out an in-depth analysis of in-cylinder combustion,mesh sensitivity,and engine performance at supercharge conditions to provide a foundation for the design improvement process of the given engine.The computational fluid dynamic(CFD)simulations are carried out on a 3D sector from-130°to 130°crank angle(CA)by employing appropriate models to represent the different physical and chemical processes and using the finite volume method for solving the governing differential equations.An extensive investigation has been carried out for the choice of base mesh size and the number of local and temporal refinements to capture the phenomena happening in the combustion chamber at diverse temporal and local scales.The present results have been validated against available literature experimental and simulation results.Primary field variables and the wellknown four phases of combustion have been studied for gaining in-depth insight into these phenomena.Cylinder average pressure,mean temperature,heat release rate(HRR),integrated heat release rate(IHRR),and emissions of CO_(2),CO,NOx,HC and soot are presented to assess the quality of combustion.Engine performance analysis has been done in terms of combustion ef-ficiency,gross work,power,torque,and integrated mean effective pressure(IMEP).The base mesh of 1.4 mm may be an appropriate choice during the injection and combustion process spanning throughout around 40CA from the start of injection while in the remaining simulation duration of around 220CA base mesh of 2 mm gives a sufficient resolution.It has been found that maximum heat release takes place in Phase-III,the mixing-controlled phase,of the combustion process.More than 98%combustion efficiency has been achieved in all the simulations.Around 99%of the total heat release and emissions production takes place within 60CA after top dead center(ATDC).
