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| 1 | Contrasting trends of PM2.5 and surface-ozone concentrations in China from 2013 to 2017显示文摘Although much attention has been paid to investigating and controlling air pollution in China,the trends of air-pollutant concentrations on a national scale have remained unclear.Here,we quantitatively investigated the variation of air pollutants in China using long-term comprehensive data sets from 2013 to 2017,during which Chinese government made major efforts to reduce anthropogenic emission in polluted regions.Our results show a significant decreasing trend in the PM2.5 concentration in heavily polluted regions of eastern China,with an annual decrease of〜7%compared with measurements in 2013.The measured decreased concentrations of SO2>NO2 and CO(a proxy for anthropogenic volatile organic compounds)could explain a large fraction of the decreased PM2.5 concentrations in different regions.As a consequence;the heavily polluted days decreased significantly in corresponding regions.Concentrations of organic aerosol;nitrate;sulfate,ammonium and chloride measured in urban Beijing revealed a remarkable reduction from 2013 to 2017;connecting the decreases in aerosol precursors with corresponding chemical components closely.However;surface-ozone concentrations showed increasing trends in most urban stations from 2013 to 2017;which indicates stronger photochemical pollution.The boundary-layer height in capital c让ies of eastern China showed no significant trends over the Beijing-Tianjin-Hebei,Yangtze River Delta and Pearl River Delta regions from 2013 to 2017;which confirmed the reduction in anthropogenic emissions.Our results demonstrated that the Chinese government was successful in the reduction of particulate matter in urban areas from 2013 to 2017,although the ozone concentration has increased significantly;suggesting a more complex mechanism of improving Chinese air quality in the future. | Yonghong Wang Wenkang Gao Shuai Wang Tao Song Zhengyu Gong Dongsheng Ji Lili Wang Zirui Liu Guiqian Tang Yanfeng Huo Shili Tian Jiayun Li Mingge Li Yuan Yang Biwu Chu Tuukka Petaja Veli-Matti Kerminen Hong He Jiming Hao Markku Kulmala Yuesi Wang Yuanhang Zhang | 2020 | National Science Review2020，7，8： | 51 |
| 2 | Trends in particulate matter and its chemical compositions in China from 2013–2017显示文摘Accurate determination of the atmospheric particulate matter mass concentration and chemical composition is helpful in exploring the causes and sources of atmospheric enthalpy pollution and in evaluating the rationality of environmental air quality control strategies.Based on the sampling and chemical composition data of PM2.5 in different key regions of China in the CARE-China observation network,this research analyzes the environmental air quality data released by the China National Environmental Monitoring Centre during the studied period to determine the changes in the particulate matter mass concentration in key regions and the evolution of the corresponding chemical compositions during the implementation of the Action Plan for Prevention and Control of Air Pollution from 2013-2017.The results show the following.(1)The particulate matter mass concentration in China showed a significant downward trend;however,the PM2.5 annual mass concentration in 64%of cities exceeds the New Chinese Ambient Air Quality Standard(CAAQS)GradeⅡ(GB3095-2012).The region to the east of the Taihang Mountains,the Fenhe and Weihe River Plain and the Urumqi-Changji regions in Xinjiang,all have PM2.5 concentration loading that is still high,and heavy haze pollution occurred frequently in the autumn and winter.(2)During the heavy pollution in the autumn and winter,the concentrations of sulfate and organic components decreased significantly.The mean SO42-concentration in PM2.5 decreased by 76%,12%,81%and 38%in Beijing-Tianjin-Hebei(BTH),the Pearl River Delta(PRD),the Sichuan-Chongqing region(SC)and the Fenhe and Weihe River Plain,respectively.The mean organic matter(OM)concentration decreased by 70%,44%,48%and 31%,respectively,and the mean concentration of NH4+decreased by 68%,1.6%,38%and 25%,respectively.The mean elemental carbon(EC)concentration decreased by 84%and 20%in BTH and SC,respectively,and it increased by 61%and 11%in the PRD and Fenhe and Weihe River Plain,respectively.The mean concentration of mineral and unresolved chemical components(MI)dropped by 70%,24%and 13%in BTH,the PRD and the Fenhe and Weihe River Plain,respectively.The change in the PM2.5 chemical composition is consistent with the decrease of the PM2.5mass concentration.(3)In 2015,the mean OM concentration contributions to fine particles and coarse particles were 13-46%and 46-57%,respectively,and the mean MI concentration contributions to fine particles and coarse and particles were 31-60%and 39-73%,respectively;these values are lower than the 2013 values from the key regions,which is the most important factor behind the decrease of the particulate matter mass concentration.From 2013 to 2015,among the chemical components of different particle size fractions,the peak value of the coarse particle size fraction decreased significantly,and the fine particle size fractions of SO42-,NO3-,and NH4+decreased with the decrease of the particulate matter mass concentration in different particle size fractions.The fine-particle size peaks of SO42-,NO3-and NH4+shifted from 0.65-1.1μm to the finer size range of0.43-0.65μm during the same time frame. | Yuesi WANG Wenjie LI Wenkang GAO Zirui LIU Shili TIAN Rongrong SHEN Dongsheng JI Shuai WANG Lili WANG Guiqian TANG Tao SONG Mengtian CHENG Gehui WANG Zhengyu GONG Jiming HAO Yuanhang ZHANG | 2019 | Science China Earth Sciences2019，62，12： | 23 |
| 3 | 运载火箭自主动态轨迹优化控制的进展显示文摘This paper first introduces the technical requirements for autonomous flight, with a brief review of the International Academy of Astronautics(IAA) study group, 'autonomous dynamic trajectory optimization control of launch vehicle'. Two research scenarios, ascent rescue and powered descent, are compared from the viewpoint of optimal control. On this basis, the technologies on the autonomous trajectory planning and control under the thrust-drop failures in the ascending phase, and the autonomous guidance method during the powered landing for the recovery of the rockets are discussed respectively. For the ascending problem, the characteristics of different solutions, including the iterative guidance method(IGM)-based residual carrying capacity evaluation, the state-triggered indices(STI), the joint planning with the payload’s performance, and the multiple graded optimization(MGO), are analyzed for comparison. For the landing problem, the challenges such as the feasible region reduction caused by high thrust weight ratio(HTWR) and the disturbance adaptability brought by the limited feasible region, are studied in detail, as well as the onboard planning demonstration flight in China are introduced. Finally, the foundations supporting the above methods are summarized, which play an important role in promoting the flight autonomy. | SONG Zhengyu | 2020 | Aerospace China2020，21，2： | 3 |
| 4 | Predictors of anti-vascular endothelial growth factor treatment responses in macular edema following central vein occlusion显示文摘Retinal vein occlusion (RVO) ranged the second common cause of retinal vascular disease,consisting of central retinal vein occlusion (CRVO) and branch retinal vein occlusion (BRVO).1,2 Although the prevalence of CRVO was one-third of BRVO,it associated with worse prognosis both before and after the anti-vascular endothelial growth factor (VEGF) regimes came into clinic use.A recent pooled age-and sex-standardized analysis showed that the prevalence was 0.8 per 1 000 (CI:0.61-0.99) for CRVO around the world.3 Similarly,in our country,the 10-year incidence of CRVO in Beijing (2001-2011) was 0.3±0.1 per 100 persons. | Huang Peirong Song Zhengyu Sun Xiaodong | 2014 | Chinese Medical Journal2014，，16： | 3 |
| 5 | Radiation belt electron scattering by whistler-mode chorus in the Jovian magnetosphere: Importance of ambient and wave parameters显示文摘Whistler-mode chorus waves are regarded as an important acceleration mechanism contributing to the formation of relativistic and ultra-relativistic electrons in the Jovian radiation belts. Quantitative determination of the chorus wave driven electron scattering effect in the Jovian magnetosphere requires detailed information of both ambient magnetic field and plasma density and wave spectral property, which however cannot be always readily acquired from observations of existed missions to Jupiter. We therefore perform a comprehensive analysis of the sensitivity of chorus induced electron scattering rates to ambient magnetospheric and wave parameters in the Jovian radiation belts to elaborate to which extent the diffusion coefficients depend on a number of key input parameters. It is found that quasi-linear electron scattering rates by chorus can be strongly affected by the ambient magnetic field intensity, the wave latitudinal coverage, and the peak frequency and bandwidth of the wave spectral distribution in the Jovian magnetosphere, while they only rely slightly on the background plasma density profile and the peak wave normal angle, especially when the wave emissions are confined at lower latitudes. Given the chorus wave amplitude, chorus induced electron scattering rates strongly depend on Jovian L-shell to exhibit a tendency approximately proportional to L_J^3. Our comprehensive analysis explicitly demonstrates the importance of reliable information of both the ambient magnetospheric state and wave distribution property to understanding the dynamic electron evolution in the Jovian radiation belts and therefore has implications for future mission planning to explore the extreme particle radiation environment of Jupiter and its satellites. | BinBin Ni Jing Huang YaSong Ge Jun Cui Yong Wei XuDong Gu Song Fu Zheng Xiang ZhengYu Zhao | 2018 | Earth and Planetary Physics2018，2，1： | 3 |
| 6 | 基于数值仿真的全箭动特性获取技术显示文摘and then in the absence of test data to establish the dynamic model.The issue was,how to accurately obtain the mode data of LM-8 with numerical simulations which directly affects the control reliability of flight.In this paper,various approaches to obtain the dynamic characteristics of LM-8 are described from the perspective of refined dynamic modeling and simulating,mode slope prediction,vertical modal test,etc.The numerical simulations were found to be in good agreement with the experimental data,and satisfied the requirements for the engineering application,which effectively supported the successful maiden flight mission of LM-8. | YANG Shutao YUAN He XU Shanshu WU Yitian SONG Zhengyu | 2021 | Aerospace China2021，22，2： | 2 |
| 7 | Autonomous mission reconstruction during the ascending flight of launch vehicles under typical propulsion system failures显示文摘In recent years, Chinese Long March(LM) launchers have experienced several launch failures, most of which occurred in their propulsion systems, and this paper studies Autonomous Mission Reconstruction(AMRC) technology to alleviate losses due to these failures. The status of the techniques related to AMRC, including trajectory and mission planning, guidance methods,and fault tolerant technologies, are reviewed, and their features are compared, which reflect the challenges faced by AMRC technology. After a brief introduction about the failure modes of engines that can occur during flight, and the fundamentals of trajectory planning and joint optimization of the target orbit and flight path, an AMRC algorithm is proposed for geostationary transfer orbit launch missions. The algorithm evaluates the residual performance onboard, and plans new objectives and corresponding flight path by iterative guidance mode or segmented state triggered optimization methods in real-time. Three failure scenarios that have occurred during previous LM missions are simulated to check the robustness of the algorithm: imminent explosion risk of the boosters’ engines, thrust drop during the first stage of flight, and being unable to start the engine during the second stage. The payloads would fall from space according to the current design under these conditions, but they were saved with the AMRC algorithm in the simulations, which allowed the rocket to get into the target orbit as intended or the payloads were deployed in other orbits without crashing. Although spaceflight can be very unforgiving, the AMRC algorithm has the potential to avoid the total loss of a launch mission when faced with these kinds of typical failures. | Zhengyu SONG Yin LIU Yong HE Cong WANG | 2022 | Chinese Journal of Aeronautics2022，35，6： | 2 |
| 8 | A New Location Precision Model for Multi-Static Over-the-Horizon Radar System显示文摘In this paper, a multi-static system working in an active way is made up of ionospheric oblique backscatter sounding system (IOBSS) and two separate receiving stations, which adopts discontinuous wave mechanism. We have advanced a new model that contains skywave condition to locate over-the-horizon targets. We use a single quasi-parabolic (QP) ionosphere model and an analytic ray-tracing program to obtain the coordinate registration (CR) index, which changes skywave group range to ground range. Also, IOBSS and other two receiving stations use this distance information to locate the target which is far away from the system. The analytic expression for the geometric dilution of precision (GDOP) under different station deployments are obtained, which shows GDOP is influenced by the system measurement precision, the stations' coordinates, and CR index. By computer simulation, we find that GDOP of isosceles right triangle deployment is smaller than that of line deployment and location precision will be improved with increasing base line length. The results indicate that this model is practicable with an acceptable range of error (less than 500 m under certain conditions in this paper). | SONG Jun, ZHAO Zhengyu, ZHOU Chen School of Electronic Information, Wuhan University, Wuhan 430072, Hubei, China | 2010 | Wuhan University Journal of Natural Sciences2010，15，2： | 2 |
| 9 | The Research on Key Technologies of Chinese Heavy-Lift Launch Vehicle Control System显示文摘This paper reviewed the development of control technology in domestic and foreign launch vehicle(LV), and based on which, the key technologies of control system for Chinese heavy-lift launch vehicles were proposed. A dynamic on-line trajectory planning technique was discussed to meet the demand of guidance control under complex constraints, and model based identification and adaptive control technology was suggested to deal with the control problems caused by model uncertainty and disturbance, and an integrated avionics system based on high speed communication was put forward for module integration and distributed control, and FBG based real time flight control was also discussed. Moreover, other key technologies, such as wireless interconnection, wireless power transfer, and temporal and spatial partitioning operating system, are both briefly introduced for the application in control systems. These studies will lead to breakthroughs in autonomous flight control in LV, and provide technical support for more long-term deep space explorations. | SONG Zhengyu | 2017 | Aerospace China2017，18，2： | 2 |
| 10 | Intelligent and Autonomous Flight Technology for Launch Vehicles显示文摘This paper proposes the architecture of an intelligent flight launcher system as well as fundamental solutions to capability prediction and dynamic planning. This effort reflects the latest progress in the applications of intelligent and autonomous technology for launcher flights. The paper first describes the characteristics and capabilities of intelligent and autonomous systems and classifies various related technologies. In the context of intelligent and autonomous technology in aerospace engineering, it then focuses on technical difficulties involved with intelligent flight and reviews developments in the field. An E^3 classification model of an intelligent flight launcher is then proposed and its application scenarios are discussed. Based on an intelligent flight system configuration of the launcher, the online trajectory planning and initial value guess are examined, and vertical landing is provided as an example to explain the effects of the implementation of computational intelligence to flight systems. | SONG Zhengyu | 2018 | Aerospace China2018，19，2： | 2 |
| 11 | Joint observation results of Na layer and ionosphere in Wuhan during the Total Solar Eclipse显示文摘During the total solar eclipse on July 22, 2009 in Wuhan, the joint observation test of Na layer and ionosphere was conducted by using the daytime observation atmospheric lidar and the GPS ionosphere detector. The results show that the full width at half maximum(FWHM) of Na layer density slightly narrowed during the total solar eclipse and broadened after the eclipse, while the height of Na peak slightly decreased in the eclipse and increased after the eclipse. These implying that Na layer changes reflect the rapid process of sunrise and sunset. The ionosphere total electron content(TEC) and the sky background light noise also presented an obvious fluctuation characteristic with the changes of solar irradiation during the process of total solar eclipse. The difference lies in that the changes of FWHM of Na layer atoms are much slower than that of ionosphere, the reason for this might be that the Na layer, after being disturbed by the total solar eclipse, will generate a series of complicated photochemical reactions and momentum transport processes, and then recombine the Na atoms. The Na atoms to be detected by the lidar need a lag process, which rightly conforms to the theoretical simulated results. | CHENG XueWu YANG Yong WANG ZeLong LI FaQuan YANG GuoTao ZHAO ZhengYu GONG Wei WANG JiHong HU Xiong LIN Xin WU XiaoCheng SONG ShaLei GONG ShunSheng | 2016 | Science China Earth Sciences2016，59，2： | 1 |
| 12 | Three-dimensional regulation of transcription显示文摘房间能适应环境,没有改变内在的 DNA,他们的 transcriptional 联网调整多样的细胞的进程的由重建的开发定序。这些改变,也就是, epigenetic 变化,发生在房间分割,区别和房间死亡期间。众多的证据证明 epigenetic 变化被决定因素的各种各样的类型管理,包括 DNA methylation 模式, histone posttranslational 修正签名, histone 变体,改变的染色质,和最近发现的染色体符合构造特征和非编码的 RNA (ncRNAs ) 。这里,我们加亮二个后者 epigenetic 因素怎么参予复杂 transcriptional 过程并且描述允许我们揭开并且获得卓见进迷人的 genomic 规定的新兴的技术的最近的努力。 | Jun Cao Zhengyu Luo Qingyu Cheng Qianlan Xu Yan Zhang Fei Wang Yan Wu Xiaoyuan Song | 2015 | Protein & Cell2015，6，4： | 1 |
| 13 | 新一代低温液体中型运载火箭显示文摘The maiden flight of LM-8 performed perfectly on December 22,2020.The design concept of modularization,seriation and combination has been perfectly exhibited in LM-8.The four main technical innovations,including rapid integrated design based on modularization,engine thrust regulation,modal parameters acquisition technology based on numerical simulation,and flight load control,were verified during the maiden flight.LM-8 is now positioned to be the main force in China’s medium launch vehicles for commercial launch.In the future,the mission adaptability of LM-8 will be improved to provide efficient and low-cost launch services.In addition,new technologies to allow repeated use and autonomous flight will be validated. | CHEN Xiaofei YU Long YUAN He ZHAO Yongzhi SONG Zhengyu ZHANG Tao | 2021 | Aerospace China2021，22，2： | 1 |
| 14 | Necrostatin-1 Protects Photoreceptors from Cell Death and Improves Functional Outcome after Experimental Retinal Detachment显示文摘 | Kai Dong Hong Zhu Zhengyu Song Yuanyuan Gong Fenghua Wang Wenqiu Wang Zhi Zheng Zhang Yu Qing Gu Xun Xu Xiaodong Sun | 2012 | The American Journal of Pathology2012，，5： | 1 |
| 15 | Toward practical quantum key distribution using telecom components显示文摘The BB84 protocol[1],as the first and the most well-known quantum key distribution(QKD)protocol,has opened up an era of secure commu-nication using quantum methods,by providing information-theoretical secure key distribution[2].In the 2000s,continuous-variable QKD(CV-QKD)was proposed as an alternative approach,and it is now going through a booming period because of its compatibility with the tele-com industry[3]. | Hong Guo Zhengyu Li Song Yu Yichen Zhang | 2021 | Fundamental Research2021，1，1： | 1 |
| 16 | Powered-Coast-Powered Guidance Recon-guration Method of Launch Vehicle with Thrust Drop Fault显示文摘This paper describes the study of a powered-coast-powered guidance recon¯guration(PCPGR)method used to solve the autonomous rescue problem for the mission pro¯le of a launch vehicle with a coasting phase when the thrust drop fault occurs in the¯rst powered phase(FPP)of the¯nal stage.We¯rst described the constraints of the¯nal stage and the construction of the PCP guidance problem.Then we evaluated the adaptability of the guidance recon¯guration(GR)o®line with numerical optimization by adjusting the constraints of the FPP,the coast phase,and the second powered phase.To determine the fault state set where the rocket can enter the prescribed target orbit through the GR initiate,we proposed a Newton method-based rapid replanning method of the transfer orbit that transforms the complex multi-°ight phase trajectory planning problem into a feasible transfer orbit search problem to produce a fast solution onboard.Combined with the adaptive adjustment of the coasting time and the iterative guidance mode,we realized the autonomous online rescue of the payload.The simulation results showed that the proposed method achieved a reliable and rapid solution and improved a launch vehicle's adaptability to a thrust drop fault. | Cong Wang Zhengyu Song | 2022 | Guidance, Navigation and Control2022，2，1： | 1 |
| 17 | Improved Delay Priority Resource Scheduling with Low Packet Loss Rate for MBMS in LTE Systems显示文摘An improved delay priority resource scheduling algorithm with low packet loss rate for multimedia broadcast multicast service(MBMS)in long term evolution(LTE)systems is proposed in this paper.Real-time services in LTE systems require lower delay and packet loss rate.However,it is difficult to meet the QoS requirements of real-time services using the current MBMS resource scheduling algorithm.The proposed algorithm in this paper jointly considers user delay information and real-time channel conditions.By introducing the user delay information,the lower delay and fairness of users are guaranteed.Meanwhile,by considering the channel conditions of users,the packet loss rate can be effectively reduced,improving the system throughput.Simulation results show that under the premise of ensuring the delay requirements of real-time services,the proposed algorithm achieves a lower packet loss rate compared to other existing algorithms.Furthermore,it can achieve a good balance between system throughput and user fairness. | Xin Sun Yuan Yang Zhengyu Song | 2020 | Journal of Beijing Institute of Technology2020，29，3： | 1 |
| 18 | Pilot Contamination Elimination in Massive MIMO Systems with an Improved Time-Shifted Scheme显示文摘Pilot contamination can bring up a grave impairment in the performance of massive multiple-input multiple-output(MIMO)systems.In this paper,an improved time-shifted pilot scheme is proposed to reduce the pilot contamination,where orthogonal pilots are employed in the same group to eliminate the residual intragroup interference existing in the original time-shifted pilot scheme.Meanwhile,the rigorous closed-form expressions of both downlink and uplink transmission rates with a finite number of antennas are derived,and it is shown that the intra-group interference can be completely eliminated by the proposed scheme.Simulation results demonstrate that both downlink and uplink transmission rates are significantly improved by employing the proposed scheme. | Yuanyuan Hao Zhengyu Song | 2020 | Journal of Beijing Institute of Technology2020，29，1： | 0 |
| 19 | Immunity-and-matrix-regulatory cells enhance cartilage regeneration for meniscus injuries: a phase I dose-escalation trial显示文摘Immunity-and-matrix-regulatory cells(IMRCs)derived from human embryonic stem cells have unique abilities in modulating immunity and regulating the extracellular matrix,which could be mass-produced with stable biological properties.Despite resemblance to mesenchymal stem cells(MSCs)in terms of self-renew and tri-lineage differentiation,the ability of IMRCs to repair the meniscus and the underlying mechanism remains undetermined.Here,we showed that IMRCs demonstrated stronger immunomodulatory and pro-regenerative potential than umbilical cord MSCs when stimulated by synovial fluid from patients with meniscus injury.Following injection into the knees of rabbits with meniscal injury,IMRCs enhanced endogenous fibrocartilage regeneration.In the dose-escalating phase I clinical trial(NCT03839238)with eighteen patients recruited,we found that intra-articular IMRCs injection in patients was safe over 12 months post-grafting.Furthermore,the effective results of magnetic resonance imaging(MRI)of meniscus repair and knee functional scores suggested that 5×107 cells are optimal for meniscus injury treatment.In summary,we present the first report of a phase I clinical trial using IMRCs to treat meniscus injury.Our results demonstrated that intra-articular injection of IMRCs is a safe and effective therapy by providing a permissive niche for cartilage regeneration. | Liangjiang Huang Song Zhang Jun Wu Baojie Guo Tingting Gao Sayed Zulfiqar Ali Shah Bo Huang Yajie Li Bo Zhu Jiaqi Fan Liu Wang Yani Xiao Wenjing Liu Yao Tian Zhengyu Fang Yingying Lv Lingfeng Xie Sheng Yao Gaotan Ke Xiaolin Huang Ying Huang Yujuan Li Yi Jia Zhongwen Li Guihai Feng Yan Huo Wei Li Qi Zhou Jie Hao Baoyang Hu Hong Chen | 2023 | Signal Transduction and Targeted Therapy2023，8，12： | 0 |
| 20 | Effects of ambient humidity and thermal aging on properties of Nomex insulation in mining dry‐type transformer显示文摘Temperature and humidity are the main factors that cause the decomposition of Nomex paper widely used as turn‐to‐turn insulation material of mining dry‐type transformers. In this study, for understanding the effect of ambient humidity and thermal aging on the properties of Nomex paper, specimens with the initial moisture content of 7% were aged in the oven for 168, 504, 672 h at 180°C, respectively. After thermal aging, corona discharge experiments of unaged and aged specimens with different aging degrees were carried out at different relative humidity (RH) levels from 10 to 70%. The characteristic parameters of corona discharge, such as the average discharge amplitude and the number of discharges, were measured. Then, the surface conductivity and the surface potential decay rate were measured. The morphology and attenuated total internal reflectance Fourier transform infrared spectroscopy were also analysed for explaining the difference of properties be-tween unaged and aged specimens. The experiment results indicate that the average discharge amplitude decreases with the increase of RH or the deepening of the aging degree of specimens, but the number of discharges shows the reversal tendency. The changes in the physical structure and chemical composition, which is induced by the hydrolysis reaction of Nomex paper, accelerate the surface potential decay and increase the surface conductivity. | Lu Li Jiancheng Song Zhipeng Lei Ailiang Kang Zhengyu Wang Rujia Men Yun Ma | 2021 | High Voltage2021，6，1： | 0 |
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