期刊文献+
共找到28篇文章
< 1 2 >
每页显示 20 50 100
The effect of gas additives on reactive species and bacterial inactivation by a helium plasma jet 被引量:2
1
作者 Han XU Chen CHEN +5 位作者 Dingxin liu Weitao WANG Wenjie XIA zhijie liu Li GUO M G KONG 《Plasma Science and Technology》 SCIE EI CAS CSCD 2019年第11期68-76,共9页
In this paper,the influences of gas doping(O2,N2,Air)on the concentrations of reactive species and bactericidal effects induced by a He plasma jet are studied.Firstly,results show that gas doping causes an increase in... In this paper,the influences of gas doping(O2,N2,Air)on the concentrations of reactive species and bactericidal effects induced by a He plasma jet are studied.Firstly,results show that gas doping causes an increase in voltage and a decrease in current compared with the pure He discharge under the same discharge power,which might be attributed to the different chemical characteristics of O2 and N2 and verified by the changes in the gaseous reactive species shown in the optical emission spectroscopy(OES)and Fourier transform infrared(FTIR)spectroscopy.Secondly,the concentrations of aqueous reactive oxygen species(ROS)and reactive nitrogen species(RNS)are tightly related to the addition of O2 and N2 into the working gas.The concentrations of aqueous NO-2 and NO-3 significantly increase while the concentrations of aqueous ROS decrease with the admixture of N2.The addition of O2 has little effect on the concentrations of NO-2 and NO-3 and pH values;however,the addition of O2 increases the concentration of O-2 and deceases the concentrations of H2O2 and OH.Finally,the results of bactericidal experiments demonstrate that the inactivation efficiency of the four types of plasma jets is He+O2>He+Air>He>He+N2,which is in accordance with the changing trend of the concentration of aqueous O.-2 Simultaneously to the better understanding of the formation and removal mechanisms of reactive species in the plasma–liquid interaction,these results also prove the effectiveness of regulating the concentrations of aqueous reactive species and the bacteria inactivation effects by gas doping. 展开更多
关键词 cold PLASMA JET REACTIVE species plasma-liquid interaction BACTERICIDAL effects
下载PDF
Modeling and Adaptive Neural Network Control for a Soft Robotic Arm With Prescribed Motion Constraints 被引量:2
2
作者 Yan Yang Jiangtao Han +2 位作者 zhijie liu Zhijia Zhao Keum-Shik Hong 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第2期501-511,共11页
This paper presents a dynamic model and performance constraint control of a line-driven soft robotic arm.The dynamics model of the soft robotic arm is established by combining the screw theory and the Cosserat theory.... This paper presents a dynamic model and performance constraint control of a line-driven soft robotic arm.The dynamics model of the soft robotic arm is established by combining the screw theory and the Cosserat theory.The unmodeled dynamics of the system are considered,and an adaptive neural network controller is designed using the backstepping method and radial basis function neural network.The stability of the closed-loop system and the boundedness of the tracking error are verified using Lyapunov theory.The simulation results show that our approach is a good solution to the motion constraint problem of the line-driven soft robotic arm. 展开更多
关键词 Adaptive control cosserat theory prescribed motion constraints soft robotic arm
下载PDF
Finite-Time Convergence Disturbance Rejection Control for a Flexible Timoshenko Manipulator 被引量:9
3
作者 Zhijia Zhao zhijie liu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2021年第1期157-168,共12页
This paper focuses on a new finite-time convergence disturbance rejection control scheme design for a flexible Timoshenko manipulator subject to extraneous disturbances.To suppress the shear deformation and elastic os... This paper focuses on a new finite-time convergence disturbance rejection control scheme design for a flexible Timoshenko manipulator subject to extraneous disturbances.To suppress the shear deformation and elastic oscillation,position the manipulator in a desired angle,and ensure the finitetime convergence of disturbances,we develop three disturbance observers(DOs)and boundary controllers.Under the derived DOs-based control schemes,the controlled system is guaranteed to be uniformly bounded stable and disturbance estimation errors converge to zero in a finite time.In the end,numerical simulations are established by finite difference methods to demonstrate the effectiveness of the devised scheme by selecting appropriate parameters. 展开更多
关键词 Disturbance observer disturbance rejection control finite-time convergence Timoshenko manipulator vibration control
下载PDF
Energy consumption and emission mitigation prediction based on data center traffic and PUE for global data centers 被引量:10
4
作者 Yanan liu Xiaoxia Wei +3 位作者 Jinyu Xiao zhijie liu Yang Xu Yun Tian 《Global Energy Interconnection》 2020年第3期272-282,共11页
With the rapid development of technologies such as big data and cloud computing,data communication and data computing in the form of exponential growth have led to a large amount of energy consumption in data centers.... With the rapid development of technologies such as big data and cloud computing,data communication and data computing in the form of exponential growth have led to a large amount of energy consumption in data centers.Globally,data centers will become the world’s largest users of energy consumption,with the ratio rising from 3%in 2017 to 4.5%in 2025.Due to its unique climate and energy-saving advantages,the high-latitude area in the Pan-Arctic region has gradually become a hotspot for data center site selection in recent years.In order to predict and analyze the future energy consumption and carbon emissions of global data centers,this paper presents a new method based on global data center traffic and power usage effectiveness(PUE)for energy consumption prediction.Firstly,global data center traffic growth is predicted based on the Cisco’s research.Secondly,the dynamic global average PUE and the high latitude PUE based on Romonet simulation model are obtained,and then global data center energy consumption with two different scenarios,the decentralized scenario and the centralized scenario,is analyzed quantitatively via the polynomial fitting method.The simulation results show that,in 2030,the global data center energy consumption and carbon emissions are reduced by about 301 billion kWh and 720 million tons CO2 in the centralized scenario compared with that of the decentralized scenario,which confirms that the establishment of data centers in the Pan-Arctic region in the future can effectively relief the climate change and energy problems.This study provides support for global energy consumption prediction,and guidance for the layout of future global data centers from the perspective of energy consumption.Moreover,it provides support of the feasibility of the integration of energy and information networks under the Global Energy Interconnection conception. 展开更多
关键词 Data center Pan-Arctic Energy consumption carbon emission Data traffic PUE Global Energy Interconnection
下载PDF
Pathogenesis and multidisciplinary management of medication-related osteonecrosis of the jaw 被引量:6
5
作者 Lina He Xiangyu Sun +2 位作者 zhijie liu Yanfen Qiu Yumei Niu 《International Journal of Oral Science》 SCIE CAS CSCD 2020年第3期209-219,共11页
Medication-related osteonecrosis of the jaw(MRONJ)is a serious side effect of bone-modifying agents and inhibits angiogenesis agents.Although the pathogenesis of MRONJ is not entirely clear,multiple factors may be inv... Medication-related osteonecrosis of the jaw(MRONJ)is a serious side effect of bone-modifying agents and inhibits angiogenesis agents.Although the pathogenesis of MRONJ is not entirely clear,multiple factors may be involved in specific microenvironments.The TGF-β1 signalling pathway may have a key role in the development of MRONJ.According to the clinical stage,multiple variables should be considered when selecting the most appropriate treatment.Therefore,the prevention and management of treatment of MRONJ should be conducted in patient-centred multidisciplinary team collaborative networks with oncologists,dentists and dental specialists.This would comprise a closed responsibility treatment loop with all benefits directed to the patient.Thus,in the present review,we aimed to summarise the pathogenesis,risk factors,imaging features,clinical staging,therapeutic methods,prevention and treatment strategies associated with MRONJ,which may provide a reference that can inform preventive strategies and improve the quality of life for patients in the future. 展开更多
关键词 PREVENTION TREATMENT entirely
下载PDF
Output Constrained Adaptive Controller Design for Nonlinear Saturation Systems 被引量:2
6
作者 Yongliang Yang zhijie liu +1 位作者 Qing Li Donald C.Wunsch 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2021年第2期441-454,共14页
This paper considers the adaptive neuro-fuzzy control scheme to solve the output tracking problem for a class of strict-feedback nonlinear systems.Both asymmetric output constraints and input saturation are considered... This paper considers the adaptive neuro-fuzzy control scheme to solve the output tracking problem for a class of strict-feedback nonlinear systems.Both asymmetric output constraints and input saturation are considered.An asymmetric barrier Lyapunov function with time-varying prescribed performance is presented to tackle the output-tracking error constraints.A high-gain observer is employed to relax the requirement of the Lipschitz continuity about the nonlinear dynamics.To avoid the"explosion of complexity",the dynamic surface control(DSC)technique is employed to filter the virtual control signal of each subsystem.To deal with the actuator saturation,an additional auxiliary dynamical system is designed.It is theoretically investigated that the parameter estimation and output tracking error are semi-global uniformly ultimately bounded.Two simulation examples are conducted to verify the presented adaptive fuzzy controller design. 展开更多
关键词 Asymmetric barrier Lyapunov function input saturation Nussbaum function time-varying prescribed performance
下载PDF
Investigation of optimum discharge characteristics and chemical activity of AC driven air plasma jet and its anticancer effect 被引量:1
7
作者 Sansan PENG Dehui XU +8 位作者 Miao QI Rong liu Xinying ZHANG Huaiyan ZHANG Bolun PANG Jin ZHANG Hao ZHANG zhijie liu Dingxin liu 《Plasma Science and Technology》 SCIE EI CAS CSCD 2021年第12期63-73,共11页
In this study,we investigated the effects of the quartz tube diameter,air flow rate,and applied voltage on the characteristics of an air plasma jet to obtain the optimized discharge characteristics.The physicochemical... In this study,we investigated the effects of the quartz tube diameter,air flow rate,and applied voltage on the characteristics of an air plasma jet to obtain the optimized discharge characteristics.The physicochemical properties and concentration of reactive oxygen and nitrogen species(RONS)in plasma-activated medium(PAM)were characterized to explore their chemical activity.Furthermore,we investigated the inactivation effect of air plasma jet on tumour cells and their corresponding inactivation mechanism.The results show that the tube diameter plays an important role in sustaining the voltage of the air plasma jet,and the gas flow rate affects the jet length and discharge intensity.Additionally,the air plasma jet discharge displays two modes,namely,ozone and nitrogen oxide modes at high and low gas flow rates,respectively.Increasing the voltage increases the concentration of reactive species and the length of discharge.By evaluating the viability of A549 cells under different parameters,the optimal treatment conditions were determined to be a quartz tube diameter of 4 mm,gas flow rate of 0.5 SLM,and voltage of 18 k V.Furthermore,an air plasma jet under the optimized conditions effectively enhanced the chemical activity in PAM and produced more aqueous RONS.The air plasma jet induced significant cytotoxicity in A549 cancer cells after plasma treatment.H_(2)O_(2) and NO_(2) are regarded as key factors in promoting cell inactivation.The present study demonstrates the potential use of tumour cell therapy by atmospheric air PAM,which aids a better understanding of plasma liquid chemistry. 展开更多
关键词 cold atmospheric plasma discharge characteristics reactive species plasma-activated medium anticancer effect
下载PDF
Mesoscale Characteristics Analysis of a Fog Case with Complete Weather Information Derived from FengYun-4A Data 被引量:1
8
作者 Wei WANG Ping QU zhijie liu 《Meteorological and Environmental Research》 CAS 2022年第2期10-27,共18页
Currently,there is a lack of sufficient ocean meteorological data required for mesoscale weather predictions and fog characteristics analysis in the North China Sea.This study presents a methodology to supplement defi... Currently,there is a lack of sufficient ocean meteorological data required for mesoscale weather predictions and fog characteristics analysis in the North China Sea.This study presents a methodology to supplement deficiencies in wind information in retrieval data from the Geostationary Interferometric Infrared Sounder(GIIRS)onboard the FengYun-4A(FY4A)satellite and analyze mesoscale weather characteristics.Atmospheric semi-geostrophic wind data were derived from semi-geostrophic theory to complete the weather elements in FY4AGIIRS retrieval data.First,the retrieval data accuracy was analyzed between L-band radiosonde data from seven stations and retrieval data from FY4AGIIRS.The errors in the temperature,humidity,and geopotential height from 850 to 400 hPa were smaller than those of other atmospheric layers.Subsequently,the mesoscale weather characteristics of a fog event were analyzed by creating a mesoscale weather map with derived weather information between 875 and 500 hPa.The analyses showed that the derived weather information might provide a new means for fog mesoscale characteristics analysis,which can help forecasters understand the spatial inhomogeneity in the visibility of fog events. 展开更多
关键词 Satellite FOG MESOSCALE Semi-geostrophic wind Weather map
下载PDF
Comparative research of plasma-assisted milling and traditional milling in synthesizing AIN
9
作者 Sen WANG Wenchun WANG +1 位作者 zhijie liu Dezheng YANG 《Plasma Science and Technology》 SCIE EI CAS CSCD 2017年第6期33-37,共5页
In this paper,traditional milling and discharge plasma-assisted milling are employed to synthesize aluminum nitride(AlN) powder at nanometer scale by milling the mixture of aluminum and lithium hydroxide monohydrate... In this paper,traditional milling and discharge plasma-assisted milling are employed to synthesize aluminum nitride(AlN) powder at nanometer scale by milling the mixture of aluminum and lithium hydroxide monohydrate.AlN powders can be generated in traditional milling and plasma-assisted milling in an hour milling time.Differential thermal analysis curves show that the reaction temperature of the powders treated by plasma-assisted milling is lower than that of traditional milling.These results indicate that plasma-assisted milling has higher efficiency in the synthesis of AlN,getting smaller crystallite size and activating powder.Moreover,an optical emission spectrum is employed to demonstrate the active species in plasma.The different formation process of AlN in the two-milling process,and the promotion effects of plasma in the milling process are discussed. 展开更多
关键词 aluminum nitride NANOPOWDER dielectric barrier discharge-assisted milling traditional milling
下载PDF
碳酸盐岩油藏提高采收率研究的新认识:固液界面影响
10
作者 刘治界 姜莎莎 +4 位作者 田茂章 王芳 马骋 宋新民 黄建滨 《中国科学:化学》 CAS CSCD 北大核心 2023年第7期1257-1264,共8页
碳酸盐岩油藏开发是目前增加我国原油产量的主攻方向之一.本文针对碳酸盐岩油藏岩石及模拟岩石样品开展固液界面作用的研究工作,从岩石的化学组成、比表面积、表面荷电情况、接触角及表面活性剂吸附量等方面,系统考察了方解石、白云石... 碳酸盐岩油藏开发是目前增加我国原油产量的主攻方向之一.本文针对碳酸盐岩油藏岩石及模拟岩石样品开展固液界面作用的研究工作,从岩石的化学组成、比表面积、表面荷电情况、接触角及表面活性剂吸附量等方面,系统考察了方解石、白云石以及中东油藏碳酸盐岩样品在洗油过程中的固液界面相互作用结果,并分析了相关体系的洗油效率.结果证实了方解石、白云石样品与中东油藏碳酸盐岩样品在组成、结构及表面性质等方面高度一致,可用于碳酸盐岩油藏固液相互作用研究的模拟样品.进而揭示了表面活性剂在碳酸盐岩表面吸附量低、对其表面润湿性改变小且洗油效率相关性差的特点,表明固液界面相互作用不是影响碳酸盐岩油藏提高采收率效果的关键因素. 展开更多
关键词 表面活性剂 固液界面 润湿性 中东碳酸盐岩油藏 提高采收率
原文传递
OGG1 inhibition suppresses African swine fever virus replication 被引量:2
11
作者 Jie Fan Xinqian Lv +10 位作者 Saixia Yang Shuxian Geng Jifei Yang Yaru Zhao Zhonghui Zhang zhijie liu Guiquan Guan Jianxun Luo Qiaoying Zeng Hong Yin Qingli Niu 《Virologica Sinica》 SCIE CAS CSCD 2023年第1期96-107,共12页
African swine fever virus(ASFV)is an important pathogen that causes a highly contagious and lethal disease in swine,for which neither a vaccine nor treatment is available.The DNA repair enzyme 8-oxoguanine DNA glycosy... African swine fever virus(ASFV)is an important pathogen that causes a highly contagious and lethal disease in swine,for which neither a vaccine nor treatment is available.The DNA repair enzyme 8-oxoguanine DNA glycosylase 1(OGG1),which excises the oxidative base lesion 8-oxo-7,8-dihydroguanine(8-oxoG),has been linked to the pathogenesis of different diseases associated with viral infections.However,the role of OGG1-base excision repair(BER)in ASFV infection has been poorly investigated.Our study aimed to characterize the alteration of host reactive oxygen species(ROS)and OGG1 and to analyse the role of OGG1 in ASFV infection.We found that ASFV infection induced high levels and dynamic changes in ROS and 8-oxoG and consistently increased the expression of OGG1.Viral yield,transcription level,and protein synthesis were reduced in ASFV-infected primary alveolar macrophages(PAMs)treated by TH5487 or SU0268 inhibiting OGG1.The expression of BER pathway associated proteins of ASFV was also suppressed in OGG1-inhibited PAMs.Furthermore,OGG1 was found to negatively regulate interferonβ(IFN-β)production during ASFV infection and IFN-βcould be activated by OGG1 inhibition with TH5487 and SU0268,which blocked OGG1 binding to 8-oxoG.Additionally,the interaction of OGG1 with viral MGF360-14-L protein could disturb IFN-βproduction to further affect ASFV replication.These results suggest that OGG1 plays the crucial role in successful viral infection and OGG1 inhibitors SU0268 or TH5487 could be used as antiviral agents for ASFV infection. 展开更多
关键词 African swine fever virus(ASFV) 8-oxoguanine DNA glycosylase 1(OGG1) 8-oxo-7 8-dihydroguanine(8-oxoG) INHIBITORS Antiviral effect
原文传递
孤儿受体GPR12自激活机制的结构基础
12
作者 李昊 张进一 +6 位作者 喻亚男 罗峰 武丽杰 刘俊林 陈娜 刘志杰 华甜 《Science Bulletin》 SCIE EI CAS CSCD 2023年第1期95-104,共10页
G蛋白偶联受体12(G protein-coupled receptor 12,GPR12)是G蛋白偶联受体(G protein-coupled receptor,GPCR)class A家族的孤儿受体成员.GPR12在丘脑中高表达,在丘脑皮层的短期记忆调控中发挥重要作用.GPR12具有高度的自激活能力,即在... G蛋白偶联受体12(G protein-coupled receptor 12,GPR12)是G蛋白偶联受体(G protein-coupled receptor,GPCR)class A家族的孤儿受体成员.GPR12在丘脑中高表达,在丘脑皮层的短期记忆调控中发挥重要作用.GPR12具有高度的自激活能力,即在没有激动剂激活的情况下可以结合下游的G蛋白Gs,使细胞内的第二信使cAMP水平上升.然而,目前关于GPR12自激活机制的分子基础以及内源性配体等都还不清楚.本研究报道了GPR12-G_(s)复合物的高分辨率单颗粒冷冻电镜结构,结合细胞水平突变实验,揭示了GPR12具有高水平自激活能力的分子机制.结构分析显示受体的胞外第二个环(extracellular loop 2,ECL2)指向正构配体结合口袋,跨膜螺旋TM1和TM7的胞外部分紧密互作,以及TM6和TM7上具有与GPR12激活相关的关键氨基酸.这些结构特征使得GPR12能够在没有激动剂作用下,受体处于激活构象状态,招募下游G蛋白进行信号传递.本研究将为靶向GPR12的内源性配体发现及相关药物分子设计提供重要的结构基础. 展开更多
关键词 内源性配体 G蛋白偶联受体 短期记忆 激活机制 药物分子设计 孤儿受体 信号传递 激动剂
原文传递
Photoswitchable vibrational nanoscopy with sub-100-nm optical resolution
13
作者 Jianpeng Ao Xiaofeng Fang +4 位作者 Liyang Ma zhijie liu Simin Wu Changfeng Wu Minbiao Ji 《Advanced Photonics》 SCIE EI CAS CSCD 2023年第6期29-36,共8页
Stimulated Raman scattering(SRS)microscopy has shown superior chemical resolution due to the much narrower vibrational spectral bandwidth than its fluorescence counterpart.However,breaking the diffraction-limited spat... Stimulated Raman scattering(SRS)microscopy has shown superior chemical resolution due to the much narrower vibrational spectral bandwidth than its fluorescence counterpart.However,breaking the diffraction-limited spatial resolution of SRS imaging is much more challenging because of the intrinsically weak scattering cross section and inert/stable nature of molecular bond vibrations.We report superresolution SRS(SR-SRS)nanoscopy based on reversible-switchable vibrational photochromic probes integrated with point spread function engineering strategy.By introducing a Gaussian-shaped ultraviolet excitation beam and a donut-shaped visible depletion beam in addition to the pump and Stokes beams,SR-SRS could reach sub-100 nm resolution on photoswitchable nanoparticles(NPs).Furthermore,NP-treated live cell imaging was demonstrated with resolution improvement by a factor of∼4.Our proof-of-principle work provides the potential for SR vibrational imaging to assist research on complex biological systems. 展开更多
关键词 stimulated Raman scattering superresolution microscopy vibrational imaging PHOTOSWITCHING
原文传递
African Swine Fever Virus MGF-110-9L-deficient Mutant Has Attenuated Virulence in Pigs 被引量:10
14
作者 Dan Li Yinguang liu +6 位作者 Xiaolan Qi Yuan Wen Pan Li Zhao Ma Yongjie liu Haixue Zheng zhijie liu 《Virologica Sinica》 SCIE CAS CSCD 2021年第2期187-195,共9页
African swine fever virus(ASFV)is the etiological agent of African swine fever(ASF),an often lethal disease in domestic and wild pigs.ASF represents a major threat to the swine industry worldwide.Currently,no commerci... African swine fever virus(ASFV)is the etiological agent of African swine fever(ASF),an often lethal disease in domestic and wild pigs.ASF represents a major threat to the swine industry worldwide.Currently,no commercial vaccine is available because of the complexity of ASFV or biosecurity concerns.Live attenuated viruses that are naturally isolated or genetically manipulated have demonstrated reliable protection against homologous ASFV strain challenge.In the present study,a mutant ASFV strain with the deletion of ASFV MGF-110-9L(ASFV-D9L)was generated from a highly virulent ASFV CN/GS/2018 parental strain,a genotypeⅡASFV.Relative to the parental ASFV isolate,deletion of the MGF-110-9L gene significantly decreased the ability of ASFV-D9L to replicate in vitro in primary swine macrophage cell cultures.The majority of animals inoculated intramuscularly with a low dose of ASFV-D9L(10 HAD50)remained clinically normal during the 21-day observational period.Three of five ASFV-D9L-infected animals displayed low viremia titers and low virus shedding and developed a strong virus-specific antibody response,indicating partial attenuation of the ASFV-D9L strain in pigs.The findings imply the potential usefulness of the ASFV-D9L strain for further development of ASF control measures. 展开更多
关键词 African swine fever virus(ASFV) MGF-110-9L MUTANT Attenuated virulence PIG
原文传递
Variational method based robust adaptive control for a guided spinning rocket 被引量:7
15
作者 Zhongjiao Shi Liangyu Zhao zhijie liu 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2021年第3期164-175,共12页
In this paper,a robust adaptive controller is designed for a guided spinning rocket,whose dynamics presents the characteristics of pitch-yaw cross coupling,fast time-varying aerodynamics parameters and wide flight env... In this paper,a robust adaptive controller is designed for a guided spinning rocket,whose dynamics presents the characteristics of pitch-yaw cross coupling,fast time-varying aerodynamics parameters and wide flight envelop.First,a coupled nonlinear six-degree-of-freedom equation of motion for a guided spinning rocket is developed,and the lateral acceleration motion is modeled as a control plant with time-varying matched uncertainties and unmodeled dynamics.Then,a robust adaptive control method is proposed by combining Bregman divergence and variational method to achieve fast adaption and maintain bounded tracking.The stability of the resulting closed-loop system is proved,and the ultimate bound and convergence rate are also analyzed.Finally,numerical simulations are performed for a single operating point and the whole flight trajectory to show the robustness and adaptability of the proposed method with respect to timevarying uncertainties and unmodeled dynamics. 展开更多
关键词 Autopilot design Guided spinning rockets Robust adaptive control Second-order adaptive law Variational method
原文传递
The first pulsar discovered by FAST 被引量:7
16
作者 Lei Qian ZhiChen Pan +20 位作者 Di Li George Hobbs WeiWei Zhu Pei Wang zhijie liu YouLing Yue Yan Zhu HongFei liu DongJun Yu JingHai Sun Peng Jiang GaoFeng Pan Hui Li HengQian Gan Rui Yao XiaoYao Xie Fernando Camilo Andrew Cameron Lei Zhang Shen Wang FAST Collaboration 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2019年第5期71-74,共4页
To assist with the commissioning [1] of the Five-hundredmeter Aperture Spherical radio Telescope (FAST), we performed a pulsar search, with the primary goal of developing and testing the pulsar data acquisition and pr... To assist with the commissioning [1] of the Five-hundredmeter Aperture Spherical radio Telescope (FAST), we performed a pulsar search, with the primary goal of developing and testing the pulsar data acquisition and processing pipelines. We tested and used three pipelines, two (Pl and P2 hereafter) searched for the periodic signature of pulsars whereas the other one was used to search for bright single pulses (P3 hereafter). 展开更多
关键词 pulsar TELESCOPE
原文传递
Pulsar candidate selection using ensemble networks for FAST drift-scan survey 被引量:3
17
作者 HongFeng Wang WeiWei Zhu +15 位作者 Ping Guo Di Li SiBo Feng Qian Yin ChenChen Miao ZhenZhao Tao ZhiChen Pan Pei Wang Xin Zheng XiaoDan Deng zhijie liu XiaoYao Xie XuHong Yu ShanPing You Hui Zhang FAST Collaboration 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2019年第5期61-70,共10页
The Commensal Radio Astronomy Five-hundred-meter Aperture Spherical radio Telescope(FAST) Survey(CRAFTS) utilizes the novel drift-scan commensal survey mode of FAST and can generate billions of pulsar candidate signal... The Commensal Radio Astronomy Five-hundred-meter Aperture Spherical radio Telescope(FAST) Survey(CRAFTS) utilizes the novel drift-scan commensal survey mode of FAST and can generate billions of pulsar candidate signals. The human experts are not likely to thoroughly examine these signals, and various machine sorting methods are used to aid the classification of the FAST candidates. In this study, we propose a new ensemble classification system for pulsar candidates. This system denotes the further development of the pulsar image-based classification system(PICS), which was used in the Arecibo Telescope pulsar survey, and has been retrained and customized for the FAST drift-scan survey. In this study, we designed a residual network model comprising 15 layers to replace the convolutional neural networks(CNNs) in PICS. The results of this study demonstrate that the new model can sort >96% of real pulsars to belong the top 1% of all candidates and classify >1.6 million candidates per day using a dual-GPU and 24-core computer. This increased speed and efficiency can help to facilitate real-time or quasi-real-time processing of the pulsar-search data stream obtained from CRAFTS. In addition, we have published the labeled FAST data used in this study online, which can aid in the development of new deep learning techniques for performing pulsar searches. 展开更多
关键词 PULSARS NEURAL NETWORKS data analysis
原文传递
Design and physical model experiment of an attitude adjustment device for a crawler tractor in hilly and mountainous regions 被引量:7
18
作者 Jingbin Sun Chong Meng +4 位作者 Yazhou Zhang Guoping Chu Yanjie Zhang Fuzeng Yang zhijie liu 《Information Processing in Agriculture》 EI 2020年第3期466-478,共13页
To address the problems of difficult leveling and poor stability of hill crawler tractors,an attitude adjustment device based on a parallel four-bar mechanism was designed,and the mechanical reasons for the sideslip i... To address the problems of difficult leveling and poor stability of hill crawler tractors,an attitude adjustment device based on a parallel four-bar mechanism was designed,and the mechanical reasons for the sideslip instability of hill crawler tractors were analyzed.On this basis,a posture adjustment mechanism based on a parallel four-bar mechanism was proposed,and the structure of the complete attitude adjustment device was designed.To ensure that this device meets the strength requirements during operation,a mechanical analysis of the key components(active rocker and slave rocker)was carried out to accommodate the load during leveling.Based on ANSYS software,a finite element simulation analysis was used to determine the maximum stress position of the active and slave rockers.Finally,to verify the accuracy of the above simulation analysis results and determine the influence rules of the lateral slope angle,longitudinal slope angle and loading quality on the abovementioned maximum stress,a physical model test bench of the attitude adjustment device was built.An orthogonal regression experiment was carried out with the maximum stresses of the active and slave rockers as the test indices.The experimental data were analyzed by Design-Expert 10 software,and the results show that the order of the primary and secondary factors influencing the maximum stress of the active rocker was the loading mass,lateral slope angle and longitudinal slope angle.The order of the factors influencing the maximum stress of the slave rocker was the longitudinal slope angle,lateral slope angle and loading mass.The active and slave rockers meet the strength requirements.This work provides technical support for the production of hill crawler tractor physical prototypes. 展开更多
关键词 Hill crawler tractor Attitude adjustment Mechanical analysis Physical model experiment
原文传递
Multifaceted function of YAP/TEAD on chromatin:prospects of‘A non-canonical role of YAP/TEAD is required for activation of estrogen-regulated enhancers in breast cancer’ 被引量:3
19
作者 Lizhen Chen zhijie liu 《Journal of Molecular Cell Biology》 SCIE CAS CSCD 2019年第12期1101-1103,共3页
Cellular function and behavior are controlled by various signals during development and disease progression in mammals.It is important to understand how signals ultimately alter the function and structure of DNA regul... Cellular function and behavior are controlled by various signals during development and disease progression in mammals.It is important to understand how signals ultimately alter the function and structure of DNA regulatory elements,especially enhancers,causing the changes of gene expression patterns.On average,each mature human cell harbors at least^100000 enhancers,but only a small percent of them have the function to activate gene expression.For instance,only^12%–18%of ERα-bound enhancers are active enhancers.How enhancers become functionally active is critical for our overall understanding of enhancer biology and gene regulation.Enhancers are recognized by signaling-dependent DNA binding transcription factors(TFs),resulting in the recruitment of different enhancer activation components that allow distal enhancers to interact with their target promoters through chromatin looping(Plank and Dean,2014).Increasing evidence indicates that the recruitment and switching of enhancer components underlie enhancer activation and the deregulation in enhancer component or architecture profoundly alters signal-regulated transcriptional machineries,leading to developmental defects or diseases. 展开更多
关键词 ACTIVATION FUNCTION instance
原文传递
Optimization of working parameters for 3MGY-200 axial air-assisted sprayer in kiwifruit orchards 被引量:2
20
作者 Chenchen Gu zhijie liu +2 位作者 Guanting Pan Yingjun Pu Fuzeng Yang 《International Journal of Agricultural and Biological Engineering》 SCIE EI CAS 2020年第2期81-91,共11页
Axial air-assisted sprayers can distribute pesticides efficiently in kiwifruit orchards.Because of improper parameter settings,most sprayers deliver either too much or too little pesticide.To identify appropriate spra... Axial air-assisted sprayers can distribute pesticides efficiently in kiwifruit orchards.Because of improper parameter settings,most sprayers deliver either too much or too little pesticide.To identify appropriate sprayer parameters for kiwifruit trees,the vertical distribution profiles of the applied liquid spray were examined in this study.The effects of spray fan speed(SFS),spray pressure(SP)and spray distance(SD)on the distributions of the sprayed liquid in the vertical profiles were studied.Combined actions of the above parameters were systematically analysed using the quadratic general rotary design test method.Regression equations for the spray liquid distributions and working factors are presented.Field confirmation experiments were carried out to optimize the parameters.Data analysis showed that the optional sprayer working parameters are those of Group 3,with an SFS equal to 1900 r/min and SP equal to 3.25 MPa.The results of this study provide a reference for future applications of this type of axial air-assisted sprayer in kiwifruit orchards. 展开更多
关键词 sprayer parameters quadratic general rotary unitized design regression equation OPTIMIZATION kiwifruit tree
原文传递
上一页 1 2 下一页 到第
使用帮助 返回顶部