The supersonic parachute plays an important role in the descent and landing of Mars missions.Next-generation supersonic parachutes,such as disksail parachutes,are alternatives to disk-gap-band(DGB)parachutes.Disksail ...The supersonic parachute plays an important role in the descent and landing of Mars missions.Next-generation supersonic parachutes,such as disksail parachutes,are alternatives to disk-gap-band(DGB)parachutes.Disksail parachutes have larger porous gaps and smaller porous seams on the canopy surface than DGB parachutes.To date,the influence mechanism of porous seams or gaps and their locations on the performance of supersonic parachute systems in Martian atmospheric conditions remains unclear.In this study,different canopy models with seams and gaps based on NASA’s supersonic disksail parachutes were designed,and the aerodynamic characteristics of such geometric porosity models were studied numerically.For seam-only models,the drag coefficient of the parachute decreases when the position of the seam is close to the middle of the canopy.When the seam is close to the mouth of the canopy,the pressure difference between the inner and outer surface of the canopy becomes small,reducing the risk of tearing the canopy.For gap-only models,the drag coefficient of the middle gap model is higher,while the lateral force stability of the top gap model is better.The results show that the addition of a seam can improve the drag performance of the top gap model and improve the lateral stability of the canopy with the middle gap.This study provides some theoretical references for designing the porosity of parachutes under different requirements for Mars exploration missions in the future.展开更多
Hepatocellular carcinoma(HCC),one of the most common gastrointestinal cancers,has been considered a worldwide threat due to its high incidence and poor prognosis.In recent years,with the continuous emergence and promo...Hepatocellular carcinoma(HCC),one of the most common gastrointestinal cancers,has been considered a worldwide threat due to its high incidence and poor prognosis.In recent years,with the continuous emergence and promotion of new sequencing technologies in omics,genomics,transcriptomics,proteomics,and liquid biopsy are used to assess HCC heterogeneity from different perspectives and become a hotspot in the field of tumor precision medicine.In addition,with the continuous improvement of machine learning algorithms and deep learning algorithms,radiomics has made great progress in the field of ultrasound,CT and MRI for HCC.This article mainly reviews the research progress of biological big data and radiomics in HCC,and it provides new methods and ideas for the diagnosis,prognosis,and therapy of HCC.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.12072377)the Natural Science Foundation of Hunan Province,China(Grant No.2022JJ30678)supported by Laboratory of Aerospace Entry,Descent and Landing Technology(Grant No.EDL19092126).
文摘The supersonic parachute plays an important role in the descent and landing of Mars missions.Next-generation supersonic parachutes,such as disksail parachutes,are alternatives to disk-gap-band(DGB)parachutes.Disksail parachutes have larger porous gaps and smaller porous seams on the canopy surface than DGB parachutes.To date,the influence mechanism of porous seams or gaps and their locations on the performance of supersonic parachute systems in Martian atmospheric conditions remains unclear.In this study,different canopy models with seams and gaps based on NASA’s supersonic disksail parachutes were designed,and the aerodynamic characteristics of such geometric porosity models were studied numerically.For seam-only models,the drag coefficient of the parachute decreases when the position of the seam is close to the middle of the canopy.When the seam is close to the mouth of the canopy,the pressure difference between the inner and outer surface of the canopy becomes small,reducing the risk of tearing the canopy.For gap-only models,the drag coefficient of the middle gap model is higher,while the lateral force stability of the top gap model is better.The results show that the addition of a seam can improve the drag performance of the top gap model and improve the lateral stability of the canopy with the middle gap.This study provides some theoretical references for designing the porosity of parachutes under different requirements for Mars exploration missions in the future.
基金supported by grants from the Natural Science Foundation of Fujian Province(2021J011283)a demonstration study on the application of domestic high-end endoscopy system and minimally invasive instruments for precise resection of hepatobiliary and pancreatic tumors(2022YFC2407304).
文摘Hepatocellular carcinoma(HCC),one of the most common gastrointestinal cancers,has been considered a worldwide threat due to its high incidence and poor prognosis.In recent years,with the continuous emergence and promotion of new sequencing technologies in omics,genomics,transcriptomics,proteomics,and liquid biopsy are used to assess HCC heterogeneity from different perspectives and become a hotspot in the field of tumor precision medicine.In addition,with the continuous improvement of machine learning algorithms and deep learning algorithms,radiomics has made great progress in the field of ultrasound,CT and MRI for HCC.This article mainly reviews the research progress of biological big data and radiomics in HCC,and it provides new methods and ideas for the diagnosis,prognosis,and therapy of HCC.
