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| 1 | Target localization method of non-cooperative spacecraft on on-orbit service显示文摘With the explosion of the number of meteoroid/orbital debris in terrestrial space in recent years, the detection environment of spacecraft becomes more complex. This phenomenon causes most current detection methods based on machine learning intractable to break through the two difficulties of solving scale transformation problem of the targets in image and accelerating detection rate of high-resolution images. To overcome the two challenges, we propose a novel noncooperative target detection method using the framework of deep convolutional neural network.Firstly, a specific spacecraft simulation dataset using over one thousand images to train and test our detection model is built. The deep separable convolution structure is applied and combined with the residual network module to improve the network’s backbone. To count the different shapes of the spacecrafts in the dataset, a particular prior-box generation method based on K-means cluster algorithm is designed for each detection head with different scales. Finally, a comprehensive loss function is presented considering category confidence, box parameters, as well as box confidence. The experimental results verify that the proposed method has strong robustness against varying degrees of luminance change, and can suppress the interference caused by Gaussian noise and background complexity. The mean accuracy precision of our proposed method reaches 93.28%, and the global loss value is 13.252. The comparative experiment results show that under the same epoch and batchsize, the speed of our method is compressed by about 20% in comparison of YOLOv3, the detection accuracy is increased by about 12%, and the size of the model is reduced by nearly 50%. | Yingxiao LI Ju HUO Ping MA Ruiye JIANG | 2022 | Chinese Journal of Aeronautics2022，35，11： | 2 |
| 2 | Probability Response of Shape Memory Alloy Beam Subjected to Noise Excitation显示文摘Shape Memory Alloy(SMA)is a typical material with memory effect,and it is widely used in many engineering fields.Based on the elastic theory and Galerkin method,a vibration system of SMA beam with rigid constraints is proposed.The non⁃smooth transformation was employed to deal with the discontinuous position,and the original system was turned into an approximate equivalent system associated with the Dirac function.Then,using the stochastic averaging method,the drift and diffusion coefficients of the corresponding Fokker Planck Kolmogorov equation were described.Lastly,the approximate probability response of the system was formulated analytically.Meanwhile,numerical simulation was carried out to verify the effectiveness of analytical results.Furthermore,stochastic bifurcation was discussed.Results show that the stationary probability response of the system was affected by the increase of noise amplitude and restitution force,and a certain restitution value and damping could induce P⁃bifurcation. | Yuting Li Jinqian Feng Yingxiao Wang | 2020 | Journal of Harbin Institute of Technology(New Series)2020，27，1： | 1 |
| 3 | Mineral Deposit Model of Cu-Fe-Au Skarn System in the Edongnan Region, Eastern China显示文摘Cu and Fe skarns are the world's most abundant and largest skarn type deposits,especially in China,and Au-rich skarn deposits have received much attention in the past two decades and yet there are few papers focused on schematic mineral deposit models of Cu-Fe-Au skarn systems.Three types of Au-rich deposits are recognized in the Edongnan region,Middle-Lower Yangtze River metallogenic belt:~140 Ma Cu-Au and Au-Cu skarn deposits and distal Au-Tl deposits.137-148 Ma Cu-Fe and 130-133 Ma Fe skarn deposits are recognized in the Edongnan region.The Cu-Fe skarn deposits have a greater contribution of mantle components than the Fe skarn deposits,and the hydrothermal fluids responsible for formation of the Fe skarn deposits involved a greater contribution from evaporitic sedimentary rocks compared to Cu-Fe skarn deposits.The carbonate-hosted Au-Tl deposits in the Edongnan region are interpreted as distal products of Cu-Au skarn mineralization.A new schematic mineral deposit model of the Cu-Fe-Au skarn system is proposed to illustrate the relationship between the Cu-Fe-Au skarn mineralization,the evaporitic sedimentary rocks,and distal Au-Tl deposits.This model has important implications for the exploration for carbonate-hosted Au-Tl deposits in the more distal parts of Cu-Au skarn systems,and Fe skarn deposits with the occurrence of gypsum-bearing host sedimentary rocks in the MLYRB,and possibly elsewhere. | XIE Guiqing MAO Jingwen ZHU Qiaoqiao HAN Yingxiao LI Wei DUAN Chao YE Hui | 2020 | Acta Geologica Sinica(English Edition)2020，94，6： | 0 |
| 4 | Recent advances and perspectives of zinc metal-free anodes for zinc ion batteries显示文摘Zinc-ion batteries(ZIBs) are recognized as potential energy storage devices due to their advantages of low cost, high energy density, and environmental friendliness. However, zinc anodes are subject to unavoidable zinc dendrites, passivation, corrosion, and hydrogen evolution reactions during the charging and discharging of batteries, becoming obstacles to the practical application of ZIBs. Appropriate zinc metal-free anodes provide a higher working potential than metallic zinc anodes, effectively solving the problems of zinc dendrites, hydrogen evolution, and side reactions during the operation of metallic zinc anodes. The improvement in the safety and cycle life of batteries creates conditions for further commercialization of ZIBs. Therefore, this work systematically introduces the research progress of zinc metal-free anodes in “rocking chair” ZIBs. Zinc metal-free anodes are mainly discussed in four categories: transition metal oxides,transition metal sulfides, MXene(two dimensional transition metal carbide) composites, and organic compounds, with discussions on their properties and zinc storage mechanisms. Finally, the outlook for the development of zinc metal-free anodes is proposed. This paper is expected to provide a reference for the further promotion of commercial rechargeable ZIBs. | Jiabing Miao Yingxiao Du Ruotong Li Zekun Zhang Ningning Zhao Lei Dai Ling Wang Zhangxing He | 2024 | International Journal of Minerals,Metallurgy and Materials2024，31，1： | 0 |
| 5 | Epigenetic regulation and mechanobiology显示文摘Mechanical force regulates a variety of cellular functions through inducing modulations in nuclear chromatin structures and epigenetic landscapes(outside in).The epigenetic modifications,in turn,regulate gene expressions and affect phenotypic outcomes,including cytoskeletal organization and cellcell/cell-ECM interactions(inside out).While there have been significant advances in the understanding of mechanotransduction in the nucleus,there is still a lack of knowledge on the potential mechanisms through which mechanical cues affect epigenetic and chromatin regulations to determine genetic outcomes.This review firstly focuses on the current understanding of epigenetic regulations and then summarizes how mechanotransduction and epigenetic modification couple together to regulate molecular and cellular functions,eventually causing functional phenotype changes e.g.,diseases.Lastly,we introduce related technologies for mechanistic studies,particularly fluorescence resonance energy transfer(FRET)biosensors for the visualization of dynamic epigenetic regulations in single living cells,as well as the applications of FRET biosensors to visualize mechanotransduction events occurring in the nucleus.These studies could provide new insights into epigenetics in regulating the physiological and pathological processes in living cells under different mechanical environments. | Shitian Li Dingyi Yang Li Gao Yingxiao Wang Qin Peng | 2020 | Biophysics Reports2020，6，2： | 0 |
| 6 | Research on the Marketing Strategy of Online Education - Taking New Oriental as an Example显示文摘In recent years,with the development of society and the progress of science and technology,online learning has penetrated into people’s daily life,and people’s demand for high-quality curriculum products is more and more strong.From a macro perspective,the continuous growth of national financial investment in education,the continuous upgrading of China’s consumption structure,the development of 5G technology and the popularization of AI intelligence make online teaching less limited.The online education industry is showing an explosive growth trend.More and more online education institutions are listed for financing,and the market value is soaring.However,in 2019,except for GSX,the latest online learning platforms such as New Oriental,Speak English Fluently and Sunlands,have been in a state of loss.Most of these agencies seize the market by increasing advertising investment,but at the same time,they also bring huge marketing costs,which affect the financial performance of the company.With the enhancement of Matthew effect,largescale educational institutions occupy a large market through free classes and low-price classes,while small and medium-sized institutions with weak capital strength are often unable to afford high sales costs,facing the risk of capital chain rupture.Taking new Oriental online as an example,this paper analyzes the problems existing in the marketing strategies of online education institutions.It also puts forward suggestions on four aspects,which are target market,differentiated value,marketing mix and marketing mode,so as to make sure that online education institutions can control marketing expenses and achieve profits by improving course quality,expanding marketing channels and implementing precise positioning. | Jialu Chen Yingxiao Han An Li | 2019 | Journal of Management Science & Engineering Research2019，2，2： | 0 |
| 7 | Genetically Encoded FRET Biosensor Detects the Enzymatic Activity of Prostate-Specific Antigen显示文摘Prostate cancer is the most common cancer among men beyond 50 years old,and ranked the second in mortality.The level of Prostate-specific antigen(PSA)in serum has been a routine biomarker for clinical assessment of the cancer development,which is detected mostly by antibody-based immunoassays.The proteolytic activity of PSA also has important functions.Here a genetically encoded biosensor based on fluorescence resonance energy transfer(FRET)technology was developed to measure PSA activity.In vitro assay showed that the biosensor containing a substrate peptide‘RLSSYYSGAG’had 400%FRET change in response to 1µg/ml PSA within 90 min,and could detect PSA activity at 25 ng/ml.PSA didn’t show enzymatic activity toward the biosensor in serum solution,likely reflecting the existence of other inhibitory factors besides Zn^(2+).By expressing the biosensor on cell plasma membrane,the FRET responses were significant,but couldn’t distinguish well the cultured prostate cancer cells from non-prostate cancer cells under microscopy imaging,indicating insufficient speci-ficity to PSA.The biosensor with the previously known‘HSSKLQ’substrate showed little response to PSA in solution.In summary,we developed a genetically encoded FRET biosensor to detect PSA activity,which may serve as a useful tool for relevant applications,such as screening PSA activation substrates or inhibitors;the purified biosensor protein can also be an alternative choice for measuring PSA activity besides currently commercialized Mu-HSSKLQ-AMC substrate from chemical synthesis. | Hui Yao Liqun Wang Jia Guo Weimin Liu Jingjing Li Yingxiao Wang Linhong Deng Mingxing Ouyang | 2020 | Molecular & Cellular Biomechanics2020，17，3： | 0 |
| 8 | Oral glucose tolerance test in diabetes,the old method revisited显示文摘The oral glucose tolerance test(OGTT)has been widely used both in clinics and in basic research for a long time.It is applied to diagnose impaired glucose tolerance and/or type 2 diabetes mellitus in individuals.Additionally,it has been employed in research to investigate glucose utilization and insulin sensitivity in animals.The main aim of each was quite different,and the details are also somewhat varied.However,the time or duration of the OGTT was the same,using the 2-h post-glucose load glycemia in both,following the suggestions of the American Diabetes Association.Recently,the use of 30-min or 1-h post-glucose load glycemia in clinical practice has been recommended by several studies.In this review article,we describe this new view and suggest perspectives for the OGTT.Additionally,quantification of the glucose curve in basic research is also discussed.Unlike in clinical practice,the incremental area under the curve is not suitable for use in the studies involving animals receiving repeated treatments or chronic treatment.We discuss the potential mechanisms in detail.Moreover,variations between bench and bedside in the application of the OGTT are introduced.Finally,the newly identified method for the OGTT must achieve a recommendation from the American Diabetes Association or another official unit soon.In conclusion,we summarize the recent reports regarding the OGTT and add some of our own perspectives,including machine learning and others. | Feng Yu Kuo Kai-Chun Cheng Yingxiao Li Juei-Tang Cheng | 2021 | World Journal of Diabetes2021，12，6： | 0 |
| 9 | Curricular Robust Reinforcement Learning via GAN-Based Perturbation Through Continuously Scheduled Task Sequence显示文摘Reinforcement learning(RL),one of three branches of machine learning,aims for autonomous learning and is now greatly driving the artificial intelligence development,especially in autonomous distributed systems,such as cooperative Boston Dynamics robots.However,robust RL has been a challenging problem of reliable aspects due to the gap between laboratory simulation and real world.Existing efforts have been made to approach this problem,such as performing random environmental perturbations in the learning process.However,one cannot guarantee to train with a positive perturbation as bad ones might bring failures to RL.In this work,we treat robust RL as a multi-task RL problem,and propose a curricular robust RL approach.We first present a generative adversarial network(GAN)based task generation model to iteratively output new tasks at the appropriate level of difficulty for the current policy.Furthermore,with these progressive tasks,we can realize curricular learning and finally obtain a robust policy.Extensive experiments in multiple environments demonstrate that our method improves the training stability and is robust to differences in training/test conditions. | Yike Li Yunzhe Tian Endong Tong Wenjia Niu Yingxiao Xiang Tong Chen Yalun Wu Jiqiang Liu | 2023 | Tsinghua Science and Technology2023，28，1： | 0 |
| 10 | Multi-temporal remote sensing of land cover change and urban sprawl in the coastal city of Yantai, China显示文摘The importance of accurately mapping and monitoring land cover changes over time is increasing,especially in rapidly growing coastal cities.In this study,three pairs of Landsat images of Yantai,a representative coastal city in China,from 1989,1999,and 2009 were selected to monitor land cover changes and urban sprawl dynamics.To improve the classification accuracy,three classification methods together with the minimum noise fraction(MNF)and pixel purity index(PPI)calculations were performed on the images.The classification results showed that the overall five-class classification accuracies averaged 91.38%for the 20-year period,which produced an accuracy of 83.78%for change maps.The analysis of change maps indicated that from 1989 to 2009,the percentage of urban area increased from 31.41%to 50.28%of the total area,and the newly urbanized area was mainly located in residential areas and the reclaimed harbor region.Analysis of the relationships between urban area and its driving forces obtained from statistical data found that the urban sprawl of Yantai before 2000 was relatively extensive,which is consistent with the conclusion drawn by using remote sensing techniques.The research results could be used as inputs for sustainable urban management and establishing Digital Earth database. | Xinyang Yu Anding Zhang Xiyong Hou Mingjie Li Yingxiao Xia | 2013 | International Journal of Digital Earth2013，6，S02： | 0 |
| 11 | CRISPR-Cas12a base editors confer efficient multiplexed genome editing in rice显示文摘Dear Editor,Many Cas9-derived base editors have been developed for precise C-to-T and A-to-G base editing in plants(Molla et al.,2021).They are typically based on a SpCas9 nickase or its engineered variants with altered protospacer adjacent motif(PAM)requirements(Molla et al.,2021).CRISPR-Cas12a enables highly efficient multiplexed genome editing in plants,and its T-rich PAM preference complements the G-rich PAM requirement of SpCas9 in genome targeting(Zhang et al.,2019,2021).Because of the lack of an efficient Cas12a nickase,it has been challenging to develop efficient Cas12a base editors.Nevertheless,Cas12a cytosine base editors(CBEs)and adenine base editors(ABEs)have been developed in mammalian cells(Li et al.,2018;Kleinstiver et al.,2019)with low DNA damage(Wang et al.,2020)because deactivated Cas12a(dCas12a)was used.However,efficient dCas12a base editors are yet to be developed in plants. | Yanhao Cheng Yingxiao Zhang Gen Li Hong Fang Simon Sretenovic Avery Fan Jiang Li Jianping Xu Qiudeng Que Yiping Qi | 2023 | Plant Communications2023，4，4： | 0 |
| 12 | Strontium ranelate incorporated 3D porous sulfonated PEEK simulating MC3T3-E1 cell differentiation显示文摘Polyetheretherketone(PEEK)has been used as an implant material because it has similar mechani-cal properties to natural bone.However,inferior osseointegration and bioinertness hamper the clinical application of PEEK.In this study,the surfaces of sulfonated three-dimensional(3D)PEEK porous structures were loaded with different concentrations of strontium ranelate,a compound commonly used in the treatment or prevention of osteoporosis by promoting bone formation and inhibiting bone resorption.Field-emission scanning electron microscopy was used to characterize the topography of the structures,elemental carbon,oxygen and strontium contents were mea-sured by X-ray photoelectron spectroscopy,and surface zeta potentials and water-contact angle were also measured.The results indicated that strontium ranelate was successfully loaded onto the 3D porous structures.In vitro cellular results showed that strontium ranelate-treated sulfonated PEEK(SP-SR)strengthened the adhesion of MC3T3-E1 cells.The activity of alkaline phosphatase,collagen secretion and extracellular matrix mineralization deposition of MC3T3-E1 cells were also improved on the surface of SP-SR.These results indicate that SP-SR could serve a new implant candidate for surgical treatment. | Yingxiao Sunt Xingdan Liu Ji Tan Dan Lv Wengang Song Rui Su Ling Li Xuanyong Liu Liping Ouyang Yun Liao | 2021 | Regenerative Biomaterials2021，8，1： | 0 |
| 13 | The Systemic Immune Inflammatory Index Predicts No-Reflow Phenomenon after Primary Percutaneous Coronary Intervention in Older Patients with STEMI显示文摘Purpose:Coronary no-reflow phenomenon(NRP),a common adverse complication in patients with ST-segment eleva-tion myocardial infarction(STEMI)treated by percutaneous coronary intervention(PCI),is associated with poor patient prognosis.In this study,the correlation between the systemic immune-inflammation index(SII)and NRP in older patients with STEMI was studied,to provide a basis for early identification of high-risk patients and improve their prognosis.Materials and methods:Between January 2017 and June 2020,578 older patients with acute STEMI admitted to the Department of Cardiology of Hebei General Hospital for direct PCI treatment were selected for this retrospective study.Patients were divided into an NRP group and normal-flow group according to whether NRP occurred during the operation.Clinical data and the examination indexes of the two groups were collected.Logistic regression was used to analyze the independent predictors of NRP,and the receiver operating characteristic curve was used to further analyze the ability of SII to predict NRP in older patients with STEMI.Results:Multivariate logistic analysis indicated that hypertension(OR=2.048,95%CI:1.252–3.352,P=0.004),lymphocyte count(OR=0.571,95%CI:0.368–0.885,P=0.012),platelet count(OR=1.009,95%CI:1.005–1.013,P<0.001),hemoglobin(OR=1.015,95%CI:1.003–1.028,P=0.018),multivessel disease(OR=2.237,95%CI:1.407–3.558,P=0.001),and SII≥1814(OR=3.799,95%CI:2.190–6.593,P<0.001)were independent predictors of NRP after primary PCI in older patients with STEMI.Receiver operating characteristic curve analysis demonstrated that SII had a high predictive value for NRP(AUC=0.738;95%CI:0.686–0.790),with the best cut-off value of 1814,a sensitivity of 52.85%and a specificity of 85.71%.Conclusion:For older patients with STEMI undergoing primary PCI,SII is a valid predictor of NRP. | Jiaqi Wang Feifei Zhang Man Gao Yudan Wang Xuelian Song Yingxiao Li Yi Dang Xiaoyong Qi | 2023 | Cardiovascular Innovations and Applications2023，7，1： | 0 |
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