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1Mathematic principles of interrupted-sampling repeater jamming (ISRJ)显示文摘Coherent jamming is one of the important trends in modern radar electronic war- fare. High-speed sampling of wideband radio frequency (RF) signals and high iso- lation of two receive-transmit antennas are key technologies for the realization of coherent jamming. However, these technologies present significant challenges to engineering application. In this paper, a novel repeater jamming based on inter- rupted sampling technique is presented. For a jammer with a receive-transmit time-sharing antenna, a radar signal is sampled with a low rate by the jammer. Then, a train of false targets will be achieved after the jamming signal feed the matched filter of a pulse compression radar. For the case of the linear frequency modulated (LFM) pulse compression radars, mathematic principles of the interrupted-sam- pling repeater jamming is developed, and then the efficiency of the jamming is de- scribed and stated as expressions of key parameters which are also beneficial to the jamming design for other coherent radars.WANG XueSong LIU JianCheng ZHANG WenMing FU QiXiang LIU Zhong XIE XiaoXia 2007Science in China(Series F)2007,50,1:53
2G-CSF is a key modulator of MDSC and could be a potential therapeutic target in colitis-associated colorectal cancers显示文摘Granulocyte 刺激殖民地的因素(G-CSF ) 是嗜中性的 trafficking 的一个必要管理者并且高度在多重肿瘤被表示。Myeloid 导出 suppressor 房间(MDSC ) 由有免疫力的抑制通过多重机制支持肿瘤的前进。尽管有在结肠癌前进的 G-CSF 功能的调查结果, MDSC 规定上的 G-CSF 和它肿瘤生长上的封锁效果的精确机制仍然是调查的一个相称的区域。在这研究,我们在一只老鼠观察了 G-CSF 的 overexpression 联系大肠炎的癌症(CAC ) 当模特儿,它与在老鼠结肠纸巾的 MDSC 的累积一致。进一步,在 vitro,研究证明 G-CSF 能通过信号变换器和表明小径的抄写 3 的使活跃之物(STAT3 ) 支持 MDSC 幸存和激活。而且与适应于不同地区生活的动物控制相比, anti-G-CSF mAb 治疗表明了减少的 MDSC 累积,它在鼠标在瘤尺寸和数字导致了显著减少。我们的结果显示 G-CSF 是在迁居,增长和 MDSC 的功能维护的一个批评调整分子,它能是为联系大肠炎的癌症的一个潜在的治疗学的目标。Wenbin Li Xinghua Zhang Yongkang Chen Yibin Xie Jiancheng Liu Qiang Feng Yi Wang Wei Yuan Jie Ma 2016Protein & Cell2016,7,2:29
3Urban traffic congestion propagation and bottleneck identification显示文摘Bottlenecks in urban traffic network are sticking points in restricting network collectivity traffic efficiency. To identify network bottlenecks effectively is a foundational work for improving network traffic condition and preventing traffic congestion. In this paper, a congestion propagation model of urban network traffic is proposed based on the cell transmission model (CTM). The proposed model includes a link model, which describes flow propagation on links, and a node model, which represents link-to-link flow propagation. A new method of estimating average journey velocity (AJV) of both link and network is developed to identify network congestion bottlenecks. A numerical example is studied in Sioux Falls urban traffic network. The proposed model is employed in simulating network traffic propagation and congestion bottleneck identification under different traffic demands. The simulation results show that continual increase of traffic demand is an immediate factor in network congestion bottleneck emergence and increase as well as reducing network collectivity capability. Whether a particular link will become a bottleneck is mainly determined by its position in network, its traffic flow (attributed to different OD pairs) component, and network traffic demand.LONG JianCheng GAO ZiYou REN HuaLing LIAN AiPing 2008Science in China(Series F)2008,51,7:25
4Progresses on microwave remote sensing of land surface parameters显示文摘Highly accurate observations at various scales on the land surface are urgently needed for the studies of many areas,such as hydrology,meteorology,and agriculture.With the rapid development of remote sensing techniques,remote sensing has had the capacity of monitoring many factors of the Earth's land surface.Especially,the space-borne microwave remote sensing systems have been widely used in the quantitative monitoring of global snow,soil moisture,and vegetation parameters with their all-weather,all-time observation capabilities and their sensitivities to the characteristics of land surface factors.Based on the electromagnetic theories and microwave radiative transfer equations,researchers have achieved great successes in the microwave remote sensing studies for different sensors in recent years.This article has systematically reviewed the progresses on five research areas including microwave theoretical modeling,microwave inversion on soil moisture,snow,vegetation and land surface temperatures.Through the further enrichment of remote sensing datasets and the development of remote sensing theories and inversion techniques,remote sensing including microwave remote sensing will play a more important role in the studies and applications of the Earth systems.SHI JianCheng DU Yang DU JinYang JIANG LingMei CHAI LinNa MAO KeBiao XU Peng NI WenJian XIONG Chuan LIU Qiang LIU ChenZhou GUO Peng CUI Qian LI YunQing CHEN Jing WANG AnQi LUO HeJia WANG YinHui 2012Science China Earth Sciences2012,55,7:24
5Comparison of Absolute Gravity Measurements Obtained with FG5/232 and FG5/214 Instruments显示文摘This paper introduces the comparison of absolute gravity measurements in China during 2006-2008,and analyzing the survey and comparing the results,it shows that there is no obvious system error between the gravimeter of FG5/214 and FG5/232,the surveying accuracy is very high and repetition is good,and their inner surveying accuracy is about 2-3 microGal.XING Lelin LI Hui LI Jiancheng HE Zhitang 2009Geo-Spatial Information Science2009,12,4:23
6Review of the characteristics and graded utilisation of coal gasification slag显示文摘The characteristics of the energy structure of rich coal,less oil and less gas,coupling with a high external dependence on oil and natural gas and the emphasis on the efficient and clean utilisation of coal,have brought opportunities for coal chemical industry.However,with the large-scale popularisation of coal gasification technology,the production and resulting storage of coal gasification slag continue to increase,which not only result in serious environmental pollution and a waste of terrestrial resources,but also seriously affect the sustainable development of coal chemical enterprises.Hence,the treatment of coal gasification slag is extremely important.In this paper,the production,composition,morphology,particle size structure and water holding characteristics of coal gasification slag are introduced,and the methods of carbon ash separation of gasification slag,both domestically and abroad,are summarised.In addition,the paper also summarises the research progress on gasification slag in building materials,ecological restoration,residual carbon utilisation and other high-value utilisation,and ultimately puts forward the idea of the comprehensive utilisation of gasification slag.For large-scale consumption to solve the environmental problems of enterprises and achieve high-value utilisation to increase the economic benefits of enterprises,it is urgent to zealously design a reasonable and comprehensive utilisation technologies with simple operational processes,strong adaptability and economic benefits.Xiaodong Liu Zhengwei Jin Yunhuan Jing Panpan Fan Zhili Qi Weiren Bao Jiancheng Wang Xiaohui Yan Peng Lv Lianping Dong 2021Chinese Journal of Chemical Engineering2021,34,7:21
7Atomic spin gyroscope based on 129Xe-Cs comagnetometer显示文摘Atomic spin gyroscope (ASG) based on comagnetometer is a high sensitive and compact gyroscope for future inertial navigation applications. The start-up time was several hours of the demonstrated ASGs based on 3He-K or21 Ne-Rb-K comagnetometer, and only a few inertial navigation applications allow such a long time for preparation. We report the demonstration of an ASG based on 129Xe-Cs comagnetometer, which decreases the start-up time to 10 minutes and decreases the operation temperature by 40% as well. By operating this ASG in spin exchange relaxation free regime, a sensitivity of 7×10 -5 °/(s Hz1/2) was achieved.FANG JianCheng QIN Jie WAN ShuangAi CHEN Yao LI RuJie 2013Chinese Science Bulletin2013,58,13:19
8Field-observation for an anticyclonic mesoscale eddy consisted of twelve gliders and sixty-two expendable probes in the northern South China Sea during summer 2017显示文摘An intensive field observation experiment using 12 Chinese gliders equipped with conductivity-temperature-depth (CTD) sensors and 62 expendable CTD probes (XCTDs) was performed to investigate the 3-D structure and time evolution of an anticyclonic eddy in the northern South China Sea (NSCS). The observed results showed that the anticyclonic eddy had a horizontal radius of about 80 km at surface and a vertical depth of impact of more than 1000 m. The largest temperature and salinity anomalies compared with the averaged values of the temperature and salinity profiles were 3.5°C and 0.4 psu at 120 m depth, respectively. Combined analysis of altimeter sea level and water mass properties indicated that the anticyclonic eddy was shed from the Kuroshio loop current. The vertical axis of the anticyclonic eddy tilted from surface to the observed maximum depth (1000 m) along its translation direction against the 2000 m isobath. The center of the anticyclonic eddy remained in the region east of Dongsha Island for more than half a month. During this time, the long axis direction of the eddy changed from across the slope to along the slope. Then, the eddy moved southward along the 2000 m isobaths. Both the geostrophic current and temperature distribution revealed that the eddy intensity weakened during the observation period gradually. These observations indicated strong interaction between the anticyclonic eddy and the slope topography of Dongsha Island.Yeqiang SHU Ju CHEN Shuo LI Qiang WANG Jiancheng YU Dongxiao WANG 2019Science China Earth Sciences2019,62,2:19
9Emission control strategies of hazardous trace elements from coal-fired power plants in China显示文摘China’s energy dependents on coal due to the abundance and low cost of coal.Coal provides a secure and stable energy source in China.Over-dependence on coal results in the emission of Hazardous Trace Elements(HTEs)including selenium(Se),mercury(Hg),lead(Pb),arsenic(As),etc.,from Coal-Fired Power Plants(CFPPs),which are the major toxic air pollutants causing widespread concern.For this reason,it is essential to provide a succinct analysis of the main HTEs emission control techniques while concurrently identifying the research prospects framework and specifying future research directions.The study herein reviews various techniques applied in China for the selected HTEs emission control,including the technical,institutional,policy,and regulatory aspects.The specific areas covered in this study include health effects,future coal production and consumption,the current situation of HTEs in Chinese coal,the chemistry of selected HTEs,control techniques,policies,and action plans safeguarding the emission control.The review emphasizes the fact that China must establish and promote efficient and clean ways to utilize coal in order to realize sustainable development.The principal conclusion is that cleaning coal technologies and fuel substitution should be great potential HTEs control technologies in China.Future research should focus on the simultaneous removal of HTEs,PM,SOx,and NOx in the complex flue gas.Adwek George Boxiong Shen Dongrui Kang Jiancheng Yang Jiangze Luo 2020Journal of Environmental Sciences2020,32,7:18
10The seasonal variations of δ^(18)O , Cl^- , Na^+ ,NO_3^- and Ca^(2+) in the snow and firn recovered from Princess Elizabeth Land, Antarctica显示文摘Snow and firn samples recovered from two snow pits (2.5 and 4.5m deep) and one 50-m firn core along the route of the 1996/1997 Chinese First Antarctic Inland Traverse Expedition in Princess Elizabeth Land, East Antarctica, have been measured for chemical composition and oxygen isotope ratio. In the two snow pits, the variations of NO3- are partly in phase with that of δ18O, while the variations of Cl- and Na+ are in inverse phase with that of δ18O.LI Zhongqin, ZHANG Mingjun, QIN Dahe, XIAO Cunde, TIAN Lide KANG Jiancheng and LI Jun Lanzhou Institute of Glaciology and Geocryology , Chinese Academy of Sciences , Lanzhou 730000, China Chinese Institute of Polar Research, Shanghai 200129, China Antarctic CRC and Australian Antarctic Division , Hobart, Australia Corresponding author 1999Chinese Science Bulletin1999,44,24:17
11A physics-based statistical algorithm for retrieving land surface temperature from AMSR-E passive microwave data显示文摘AMSR-E and MODIS are two EOS (Earth Observing System) instruments on board the Aqua satellite. A regression analysis between the brightness of all AMSR-E bands and the MODIS land surface tem-perature product indicated that the 89 GHz vertical polarization is the best single band to retrieve land surface temperature. According to simulation analysis with AIEM,the difference of different frequen-cies can eliminate the influence of water in soil and atmosphere,and also the surface roughness partly. The analysis results indicate that the radiation mechanism of surface covered snow is different from others. In order to retrieve land surface temperature more accurately,the land surface should be at least classified into three types:water covered surface,snow covered surface,and non-water and non-snow covered land surface. In order to improve the practicality and accuracy of the algorithm,we built different equations for different ranges of temperature. The average land surface temperature er-ror is about 2―3℃ relative to the MODIS LST product.MAO KeBiao SHI JianCheng LI ZhaoLiang QIN ZhiHao LI ManChun XU Bin 2007Science China Earth Sciences2007,50,7:16
12Simulation of the Whole Process of Ship-Bridge Collision显示文摘The simulation of the whole ship-bridge collision process can be effectively carried out by nonlinear dynamic finiteelement method. Based on the simple description of the theory, a scenario of a 40000 DWT oil tanker colliding with abridge across the Yangtze River is designed for simulation. The technology of structure modeling and the determination ofrelated parameters are introduced. The deformation of the bulb bow, the history of collision force change, the exchange ofcollision energy and the stress distribution of the bridge pier are described in detail, which are of great value to bridge de-sign and bridge pier damage estimation, Some mechanical characters in the process of ship-bridge collision are described.More accurate results can be produced by finite element method than that by empirical formulas and simplified analyticalmethods.LIU Jiancheng(刘建成) GU Yongning(顾永宁) 2002China Ocean Engineering2002,17,3:15
13Characterization of Nestin-positive stem Leydig cells as a potential source for the treatment of testicular Leydig cell dysfunction显示文摘Mei Hua Jiang Bing Cai Ying Tuo Jiancheng Wang Zhi Jun Zang Xiang'an Tu Yong Gao Zhijian Su Weiqiang Li Guilan Li Min Zhang Jianwei Jiao Zi Wan Chunhua Deng Bruce T Lahn Andy Peng Xiang 2014Cell Research2014,24,12:14
14Analysis of spatial distribution and multi-year trend of the remotely sensed soil moisture on the Tibetan Plateau显示文摘Long-term highly accurate surface soil moisture data of TP(Tibetan Plateau)are important to the research of Asian monsoon and global atmospheric circulation.However,due to the sparse in-situ networks,the lack of soil moisture observations has seriously hindered the progress of climate change researches of TP.Based on the Dual-Channel soil moisture retrieval algorithm and the satellite observation data of AMSR-E(Advanced Microwave Scanning Radiometer for EOS),we have produced the surface soil moisture data of TP from 2003 to 2010 and analyzed the seasonal characteristic of the soil moisture spatial distribution and its multi-year changing trend in area of TP.Compared to the in-situ observations,the accuracy of the soil moisture retrieved by the proposed algorithm is evaluated.The evaluation result shows that the new soil moisture product has a better accuracy in the TP region than the official product of AMSR-E.The spatial distribution of the annual mean values of soil moisture and the seasonal variations of the monthly-averaged soil moisture are analyzed.The results show that the soil moisture variations in space and time are consistent with the precipitation distribution and the water vapor transmission path in TP.Based on the new soil moisture product,we also analyzed the spatial distribution of the changing trend of multi-year soil moisture in TP.From the comparisons with the precipitation changing trend obtained from the meteorological observation sites in TP,we found that the spatial pattern of the changing trend of soil moisture coincides with the precipitation as a whole.LIU Qiang DU JinYang SHI JianCheng JIANG LingMei 2013Science China Earth Sciences2013,56,12:13
15Reconstruction and analysis of temporal and spatial variations in surface soil moisture in China using remote sensing显示文摘An ensemble method was used to combine three surface soil moisture products,retrieved from passive microwave remote sensing data,to reconstruct a monthly soil moisture data set for China between 2003 and 2010.Using the ensemble data set,the temporal and spatial variations of surface soil moisture were analyzed.The major findings were:(1) The ensemble data set was able to provide more realistic soil moisture information than individual remote sensing products;(2) during the study period,the soil moisture increased in semiarid regions and decreased in arid regions with anoverall drying trend for the whole country;(3) the soil moisture variation trends derived from the three retrieval products and the ensemble data differ from each other but all data sets show the dominant drying trend for the summer,and that most of the drying regions were in major agricultural areas;(4) compared with the precipitation trends derived from Global Precipitation Climatology Project data,it is speculated that climate change is a possible cause for the drying trend in semiarid regions and the wetting trend in arid regions;and (5) combining soil moisture trends with land surface temperature trends derived from Moderate Resolution Imaging Spectroradiomete,the study domain was divided into four categories.Regions with drying and warming trends cover 33.2%,the regions with drying and cooling trends cover 27.4%,the regions with wetting and warming trends cover 21.1% and the regions with wetting and cooling trends cover 18.1%.The first two categories primarily cover the major grain producing areas,while the third category primarily covers nonarable areas such as Northwest China and Tibet.This implies that the moisture and heat variation trends in China are unfavorable to sustainable development and ecology conservation.LU Hui SHI JianCheng 2012Chinese Science Bulletin2012,57,22:12
16First mass measurement of short-lived nuclides at HIRFL-CSR显示文摘Recent commissioning of the HIRFL-CSR has demonstrated its ability to perform direct mass measurement for short-lived nuclides. Projectile fragments produced by the 78Kr ions at 481.88 MeV/u were separated with the new radioactive beam line in Lanzhou (RIBLL2), and injected into and stored in the experimental storage ring (CSRe). By operating the CSRe as an isochronous mass spectrometry, a typical mass resolution around 2.0×10?5 has been achieved. The masses for 63Ge, 65As and 67Se were measured for the first time. The measured masses are compared with theoretical predictions and the location of the proton drip-line for As isotopes is discussed. The implication of the 65As mass in the astrophysical rapid proton capture process has also been addressed.XU HuShan TU XiaoLin YUAN YouJin XIA JiaWen ZANG YongDong WANG Meng MAO RuiShi HU ZhengGuo MEI Bo SHUAI Peng ZHU ZhiChao TANG ShuWen GENG Peng LIU Yong ZHAO TieCheng ZHANG XueYing YANG JianCheng MAO LiJun ZHANG YuHu ZHOU XiaoHong HUANG WenXue XIAO GuoQing ZHAO HongWei ZHAN WenLong 2009Chinese Science Bulletin2009,54,24:11
17Bathymetry predicted from vertical gravity gradient anomalies and ship soundings显示文摘In this paper,the admittance function between seafloor undulations and vertical gravity gradient anomalies was derived. Based on this admittance function,the bathymetry model of 1 minute resolution was predicted from vertical gravity gradient anomalies and ship soundings in the experimental area from the northwest Pacific. The accuracy of the model is evaluated using ship soundings and existing models,including ETOPO1,GEBCO,DTU10 and V15. 1 from SIO. The model's STD is 69. 481m,comparable with V15. 1which is generally believed to have the highest accuracy.Hu Minzhang Li Jiancheng Li Hui Xin Lelin 2014Geodesy and Geodynamics2014,5,1:9
18Start-up current adaptive control for sensorless high-speed brushless DC motors based on inverse system method and internal mode controller显示文摘The start-up current control of the high-speed brushless DC(HS-BLDC) motor is a challenging research topic. To effectively control the start-up current of the sensorless HS-BLDC motor, an adaptive control method is proposed based on the adaptive neural network(ANN)inverse system and the two degrees of freedom(2-DOF) internal model controller(IMC). The HS-BLDC motor is identified by the online least squares support vector machine(OLS-SVM) algorithm to regulate the ANN inverse controller parameters in real time. A pseudo linear system is developed by introducing the constructed real-time inverse system into the original HS-BLDC motor system. Based on the characteristics of the pseudo linear system, an extra closed-loop feedback control strategy based on the 2-DOF IMC is proposed to improve the transient response performance and enhance the stability of the control system. The simulation and experimental results show that the proposed control method is effective and perfect start-up current tracking performance is achieved.He Yanzhao Zheng Shiqiang Fang Jiancheng 2017Chinese Journal of Aeronautics2017,30,1:9
19Effect of Aidi injection plus chemotherapy on gastric carcinoma:a Meta-analysis of randomized controlled trials显示文摘OBJECTIVE: To conduct a Meta-analysis of studies on the effect of Aidi injectioncombined with chemotherapy versus chemotherapy alone in the treatment of gastric cancer(GC).METHODS: Nine electronic databases and six gray literature databases were comprehensively searcheduntil April 20,2013. Two reviewers independently selected and assessed included trialsaccording to the inclusion and exclusion criteria. The risk of bias tool from the Cochrane Handbook version 5.1.0was used to assess trial quality. All calculations were performed using Review Manager 5.0.RESULTS: Thirty-two studies including 1927 participants met the inclusion criteria,most of which were low quality. Compared with chemotherapy alone,Aidi injection plusthe same chemotherapy significantly improved the effective rate [OR = 1.52,95% CI(1.24,1.86),P < 0.0001],clinical beneficial rate [OR = 1.77,95% CI(1.33,2.36),P < 0.0001],and quality of life [OR = 3.02,95% CI(2.39,3.82),P <0.000 01]. There was a significant improvement in nausea and vomiting incidence [OR = 0.34,95%CI(0.24,0.47),P < 0.000 01],diarrhea [OR = 0.47,95%CI(0.33,0.69),P < 0.000 01],leukopenia( 3,0.51),P = 0.05],hemⅢ-ogⅣ)[OR = 0.34,95%CI(0.2lobin decrease(thromⅢ-boⅣ) [OR = 0.42,95%CI(0.18-1.00),P = 0.05],cytopenia(4],and Ⅲ-damⅣ) [OR = 0.46,95%CI(0.22,0.96),P = 0.0age to liver function [OR = 0.36,95%CI(0.24,0.54),P < 0.000 01].CONCLUSION: Aidi injection combined with chemotherapy significantly improved the clinical effect of chemotherapy,reducing the incidence of adverse events. Use of the CONSORT statement for randomized controlled trials is recommended for stricter reporting.Wang Jiancheng Ge Long Zhao Ye Li Jinlong Zhang Pan Mao Lei Yang Kehu 2015Journal of Traditional Chinese Medicine2015,35,4:9
20A review of the estimation of downward surface shortwave radiation based on satellite data:Methods, progress and problems显示文摘The estimation of downward surface shortwave radiation(DSSR)is important for the Earth’s energy budget and climate change studies.This review was organised from the perspectives of satellite sensors,algorithms and future trends,retrospects and summaries of the satellite-based retrieval methods of DSSR that have been developed over the past 10 years.The shortwave radiation reaching the Earth’s surface is affected by both atmospheric and land surface parameters.In recent years,studies have given detailed considerations to the factors which affect DSSR.It is important to improve the retrieval accuracy of cloud microphysical parameters and aerosols and to reduce the uncertainties caused by complex topographies and high-albedo surfaces(such as snow-covered areas)on DSSR estimation.This review classified DSSR retrieval methods into four categories:empirical,parameterisation,look-up table and machine-learning methods,and evaluated their advantages,disadvantages and accuracy.Further efforts are needed to improve the calculation accuracy of atmospheric parameters such as cloud,haze,water vapor and other land surface parameters such as albedo of complex terrain and bright surface,organically combine machine learning and other methods,use the new-generation geostationary satellite and polar orbit satellite data to produce highresolution DSSR products,and promote the application of radiation products in hydrological and climate models.Husi LETU Jiancheng SHI Ming LI Tianxing WANG Huazhe SHANG Yonghui LEI Dabin JI Jianguang WEN Kun YANG Liangfu CHEN 2020Science China Earth Sciences2020,63,6:8
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