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| 1 | A new global zenith tropospheric delay model IGGtrop for GNSS applications显示文摘Tropospheric delay is one of the main sources of measurement error in global navigation satellite systems.It is usually compensated by using an empirical correction model.In this paper,temporal and spatial variations of the global zenith tropospheric delay(ZTD) are further analyzed by ZTD time series from global International GNSS Service stations and annual ZTDs derived from global National Centers for Environmental Prediction reanalysis data,respectively.A new ZTD correction model,named IGGtrop,is developed based on the characteristics of ZTD.Experimental results show that this new 3D-grid-based model that accommodates longitudinal as well as latitudinal variations of ZTD performs better than latitude-only based models(such as UNB3,EGNOS,and UNB3m).The global average bias and RMS for IGGtrop are about-0.8 cm and 4.0 cm,respectively.Bias values for UNB3,EGNOS,and UNB3m are 2.0,2.0,and 0.7 cm,respectively,and respective RMS values 5.4,5.4,and 5.0 cm.IGGtrop shows much more consistent prediction errors for different areas than EGNOS and UNB3m,In China,the performance of IGGtrop(bias values from-2.0 to 0.4 cm and RMS from 2.1 to 6.4 cm) is clearly superior to those of EGNOS and UNB3m.It is also demonstrated that IGGtrop biases vary little with height,and its RMS values tend to decrease with increasing height.In addition,IGGtrop generally estimates ZTD with greater accuracy than EGNOS and UNB3m in the Southern Hemisphere. | LI Wei YUAN YunBin OU JiKun LI Hui LI ZiShen | 2012 | Chinese Science Bulletin2012，57，17： | 32 |
| 2 | Models and methods for precise determination of ionospheric delay using GPS显示文摘为精确在 GPS 观察决定 ionospheric 延期的基本原则和方法是 intorduced 并且讨论。为基于 GPS 适合 ionospheric delyas 的各种各样的方法和模型被比较并且分析,并且到研究和工程的方法和模型的应用被总结。 | YUAN Yunbin HUO Xingliang OU Jikun | 2007 | Progress in Natural Science:Materials International2007，17，2： | 25 |
| 3 | Preliminary results and analyses of using IGS GPS data to determine global ionospheric TEC显示文摘Using the spherical harmonic (SH) function model and the dual frequency GPS data of 139 International GPS Service (IGS) stations for July 15 of 2000, the global ionospheric total electron content (TEC) is calculated and the basic method is investigated. Here, preliminary results are reported and the problems and difficulties to be solved for using GPS data to determine the global ionospheric TEC are discussed. | YUAN Yunbin and OU Jikun(Laboratory of Dynamic Geodesy, Institute of Geodesy and Geophysics, Chinese Academy of Sciences, Wuhan 430077, China) | 2003 | Progress in Natural Science:Materials International2003，13，6： | 20 |
| 4 | Extraction of line-of-sight ionospheric observables from GPS data using precise point positioning显示文摘Here we propose a method for extracting line-of-sight ionospheric observables from GPS data using precise point positioning(PPP).The PPP-derived ionospheric observables(PIOs) have identical form with their counterparts obtained from leveling the geometry-free GPS carrier-phase to code(leveling ionospheric observables,LIOs),and are affected by the satellite and receiver inter-frequency biases(IFBs).Based on the co-location experiments,the effects of extracting error arising from the observational noise and multipath on the PIOs and the LIOs are comparatively assessed,and the considerably reduced effects ranging from 70% to 75% on the PIOs with respect to the LIOs can be verified in our case.In addition,based on 26 consecutive days' GPS observations from two international GNSS service(IGS) sites(COCO,DAEJ) during disturbed ionosphere period,the extracted PIOs and LIOs are respectively used as the input of single-layer ionospheric model to retrieve daily satellite IFBs station-by-station.The minor extracting errors underlying the PIOs in contrast to the LIOs can also be proven by reducing day-to-day scatter and improving between-receiver consistency in the retrieved satellite IFBs values. | ZHANG BaoCheng OU JiKun YUAN YunBin LI ZiShen | 2012 | Science China Earth Sciences2012，55，11： | 19 |
| 5 | China's Labor Transition and the Future of China's Rural Wages and Employment显示文摘This paper contributes to the assessment of China's rural labor markets.According to our data,the increase in off-farm employment that China experienced during the 1980s and1990s continued during the 2000s.Our analysis shows that migration has become the most prevalent off-farm activity,although the destination of migrants is shifting from outside of one's province to destinations closer to home.The present paper finds that large shares of male and female individuals,especially those under 40 years,are working off the farm.These findings represent an important contribution to the labor economics field.First,the results of the present paper reveal that the labor transition from the agricultural sector to the non-agricultural sector for key segments of China's rural labor force is nearly complete.Second,although a large share of China's rural labor force work in agriculture,most of these workers are older men and women(and likely would not be willing to take low-wage,labor-intensive jobs).Third,the rising unskilled wage rate in China is partially a result of the tightening of the labor force in the young age cohorts.Finally,due to factors associated with the one child policy and other demographic transition forces,successive age cohorts will continue to fall in absolute number in the coming decade.Assuming China's growth continues,we expect to see further wage increases since it will take higher wages to coax more workers to work off the farm. | Qiang Li Jikun Huang Renfu Luo Chengfang Liu | 2013 | China & World Economy2013，21，3： | 16 |
| 6 | Yaw attitude of eclipsing GPS satellites and its impact on solutions from precise point positioning显示文摘During the period when a GPS satellite,the Earth and the Sun are approximately collinear,the phenomenon of eclipsing the satellite occurs,when the satellite yaw attitude deviates from its nominal case,i.e. the body X-axis cannot point towards the Sun for Block II&IIA or away from it for Block IIR satellites. The yaw attitude of the eclipsing satellites has a significant influence on both the satellite clock estimation at each International GNSS Service (IGS) Analysis Center (AC) and for users of the precise point positioning (PPP) implementations. It is known that,during the eclipsing periods,inconsistent yaw attitude models among the ACs will contribute to the errors of the IGS combined clock products. As for the PPP user,the influence of the eclipsing satellite is two-fold. First,as the satellite clocks are always kept fixed during PPP implementation,the above-mentioned problematic IGS clocks will inevitably be passed on to the PPP estimates. Second,the improper yaw attitude modeling of the eclipsing satellite will cause a correction bias exceeding 1 dm for the two kinds of attitude-related systematic errors,namely the phase wind-up and satellite antenna phase center offset,which will further deteriorate the accuracy of the PPP solutions. A yaw attitude model is introduced in this paper with the aim of improving the reliability of PPP solutions during the satellite eclipsing period. | ZHANG BaoCheng OU JiKun YUAN YunBin ZHONG ShiMing | 2010 | Chinese Science Bulletin2010，55，32： | 8 |
| 7 | Gender and Off-farm Employment: Evidence from Rural China显示文摘现在的纸的目标是检验从 2000 的经济的扩大怎么影响了农村离开农场劳动市场参予。明确地,我们寻求决定离开农场劳动是否在 2000 以后增加了,什么雇用的形式并且是否在离开农场劳动正在驾驶趋势性差别能在离开农场雇用趋势被观察。用全国地代表性的数据集由在六个省在 2000 和 2008 进行的调查的二个波浪组成,这份报纸发现那离开农场劳动市场参予继续在 2000 年代初稳定地起床。然而,在在 2000 前后与职业选择联系的趋势有清楚的差别。另外,我们发现农村离开农场雇用趋势为男人和女人是不同的。我们的分析也证明挣工资的雇用的上升与增加相应为男人和女人的不熟练的工资。 | Xiaobing Wang Linghui Han Jikun Huang Linxiu Zhang Scott Rozelle | 2016 | China & World Economy2016，24，3： | 8 |
| 8 | Impact of China-ASEAN Free Trade Area on China's International Agricultural Trade and Its Regional Development显示文摘This study aims to examine the impact of the China–ASEAN Free Trade Area (CAFTA) on China’s international agricultural trade and its regional agricultural development, using the Global Trade Analysis Project model and the China Agricultural Decision Support System. Our analysis showed that: (i) CAFTA will improve resource allocation efficiencies for both China and ASEAN and will promote bilateral agricultural trade and, hence, will have positive effects on the economic development of both sides; (ii) CAFTA will accelerate China’s export of the agricultural commodities in which it has comparative advantages, such as vegetables, wheat and horticultural products, but at the same time bring about a large increase in imports of commodities such as vegetable oil and sugar; and (iii) CAFTA will have significantly varying impacts on China’s regional agricultural development because of large differences in the agricultural production structure in each region. Our results indicate that agriculture in the northern, northeastern and eastern regions of China will benefit from CAFTA, whereas agriculture development in southern China will suffer. Those regional specific impacts are quite different from the effects brought by multilateral free trade treaties, such as those of the WTO, which usually have positive effects on south China but negative impacts on the northern and western parts of China. | Huanguang Qiu Yang Jun Jikun Huang Ruijian Chen | 2007 | China & World Economy2007，15，5： | 8 |
| 9 | Impacts of El Nino-Southern Oscillation events on China's rice production显示文摘This paper aims to demonstrate the relationships between ENSO and rice production of Jiangxi province in order to identify the reason that ENSO might have little effect on Chinese rice production. Using a data set with measures of Jiangxi's climate and rice production,we find the reason that during 1985 and 2004 ENSO's well correlated with rainfall did not promote Chinese rice production. First,the largest effects of ENSO mostly occur in the months when there is no rice in the field. Second,there is almost no temperature effect. Finally,the monthly distribution of rainfall is almost the same in ENSO and neutral years because the largest effects are during months when there is the least rain. In addition,due to the high irrigation share and reliable and effective irrigation facilities of cultivated land,China's rice production is less climate-sensitive. | DENG Xiangzheng HUANG Jikun QIAO Fangbin Rosamond L. Naylor Walter P. Falcon Marshall Burke Scott Rozelle David Battisti | 2010 | Journal of Geographical Sciences2010，20，1： | 7 |
| 10 | Potential land for plantation of Jatropha curcas as feedstocks for biodiesel in China显示文摘As a renewable energy,biofuel has attracted great attention in China and the rest of world.Concerned with the national food security,China recently has shifted its biofuel development priority from grain-based to non-grain-based biofuels,including forest-based biodiesel,since 2007.Jatropha curcas is one of major biodiesel feedstocks.However,there is rising debate on availability of land for expanding Jatropha curcas areas.The overall goal of this paper is to evaluate potential land for Jatropha curcas used as feedstock for biodiesel in China.Based on remote sensing data on land use,data on meteorological,soil and land slope,and suitable environment for Jatropha curcas plantation,this study uses Agro Ecological Zone method and considers social-economic constraints to evaluate potential suitable land for Jatropha curcas plantation in China's major Jatropha curcas production region,Southwest China.The results show that while there are some potential lands to expand Jatropha curcas areas,amount of these lands will hardly meet the government's target for Jatropha curcas-based biodiesels development in the future.China may need to reconsider its long-term targets on the development of Jatropha curcas-based biodiesels. | WU WeiGuang 1,2,3,HUANG JiKun 1,3 & DENG XiangZheng 1,3 1 Institute of Geographic Sciences and Natural Resources Research,Chinese Academy of Sciences,Beijing 100101,China 2 Department of Economics and Management,Zhejiang Forestry University,Linan 311300,China 3 Center for Chinese Agricultural Policy,Chinese Academy of Sciences,Beijing 100101,China | 2010 | Science China Earth Sciences2010，53，1： | 7 |
| 11 | Synergistic therapy of magnetism-responsive hydrogel for soft tissue injuries显示文摘Soft tissue injury is very common and associated with pain,tissue swelling and even malformation if not treated on time.Treating methods include cryotherapy,electrical therapy,ultrasound therapy and anti-inflammatory drug,but none of them is completely satisfying.In this work,for a better therapeutic effect,drug therapy and pulsed electromagnetic field(PEMF)therapy were combined.We constructed a drug delivery system using the tetra-PEG/agar hydrogel(PA).By incorporating Fe3O4 NPs into the hydrogel network,a magnetism-responsive property was achieved in the system.The cytotoxicity and in vivo study showed a good biocompatibility of the PA/Fe3O4 hydrogel.A magnetism-controlled release was attained by the incorporation of Fe3O4.Finally,in vivo study showed a better performance of the DS-loaded PA/Fe3O4 compared with the commercially available DS ointment regarding the recovery of the injured soft tissue.Therefore,this magnetism-responsive hydrogel may represent a promising alternative to treat soft tissue injury. | Lining Zhang Xiuqin Zuo Shengjie Li Mi Sun Huimin Xie Kai Zhang Jikun Zhou Liyun Che Junxuan Ma Zishan Jia Fei Yang | 2019 | Bioactive Materials2019，4，1： | 7 |
| 12 | The phylogenetic status of typical Chinese native pigs: analyzed by Asian and European pig mitochondrial genome sequences显示文摘China is one of the most diverse countries, which have developed 88 indigenous pig breeds. Several studies showed that pigs were independently domesticated in multiple regions of the world. The purpose of this study was to investigate the origin and evolution of Chinese pigs using complete mitochondrial genomic sequences (mtDNA) from Asian and European domestic pigs and wild boars. Thirty primer pairs were designed to determine the mtDNA sequences of Xiang pig, Large White, Lantang, Jinhua and Pietrain. The phylogenetic status of Chinese native pigs was investigated by comparing the mtDNA sequences of complete coding regions and D-loop regions respectively amongst Asian breeds, European breeds and wild boars. The analyzed results by two cluster methods contributed to the same conclusion that all pigs were classified into two major groups, European clade and Asian clade. It revealed that Chinese pigs were only recently diverged from each other and distinctly different from European pigs. Berkshire was clustered with Asian pigs and Chinese pigs were involved in the development of Berkshire breeding. The Malaysian wild boar had distant genetic relationship with European and Asian pigs. Jinhua and Lanyu pigs had more nucleotide diversity with Chinese pigs although they all belonged to the Asian major clade. Chinese domestic pigs were clustered with wild boars in Yangtze River region and South China. | Guanghui Yu Hai Xiang Jikun Wang Xingbo Zhao | 2013 | Journal of Animal Science and Biotechnology2013，4，2： | 7 |
| 13 | Design and Experimental Research on Seedling Pick-Up Mechanism of Planetary Gear Train with Combined Non-circular Gear Transmission显示文摘Currently, transplanting mechanisms for dryland plug seedlings in China are mainly semiautomatic and have low efficiency. The rotary seedling pick-up mechanism with a planetary gear train for non-uniform intermittent transmission, and a concave and convex locking arc device, has a large rigid impact. To solve these problems, according to the design requirements for a dryland plug seedling transplanting mechanism, a rotary seedling pick-up mechanism of a planetary gear train with combined non-circular gear transmission of incomplete eccentric circular and noncircular gears was proposed. This has the characteristics of two-times greater fluctuation of the transmission ratio in a cycle, and can achieve a non-uniform continuous drive. Through analysis of the working principle of the seedling pick-up mechanism, its kinematics model was established. The human–computer interaction optimization method and self-developed computer-aided analysis and optimization software were used to obtain a set of parameters that satisfy the operation requirements of the seedling pick-up mechanism. According to the optimized parameters, the structure of the seedling pick-up mechanism was designed, a virtual prototype of the mechanism was created, and a physical prototype was manufactured. A virtual motion simulation of the mechanism was performed, high-speed photographic kinematics tests were conducted, and the kinematic properties of the physical prototype were investigated, whereby the correctness of the theoretical model and the optimized design of the mechanism were verified. Further, laboratory seedling pick-up tests were conducted. The success ratio of seedling pick-up was 93.8% when the seedling pick-up efficiency of the mechanism was 60 plants per minute per row, indicating that the mechanism has a high efficiency and success ratio for seedling pick-up and can be applied to a dryland plug seedling transplanter. | Yaxin Yu Jikun Liu Bingliang Ye Gaohong Yu Xuejun Jin Liang Sun Junhua Tong | 2019 | Chinese Journal of Mechanical Engineering2019，32，3： | 7 |
| 14 | Massive lithospheric delamination in southeastern Tibet facilitating continental extrusion显示文摘Significant left-lateral movement along the Ailao Shan-Red River fault accommodated a substantial amount of the late Eocene to early Miocene India-Asia convergence.However,the activation of this critical strike-slip fault remains poorly understood.Here,we show key seismic evidence for the occurrence of massive lithospheric delamination in southeastern Tibet.Our novel observation of reflected body waves(e.g.P_(410)P and P_(660)P)retrieved from ambient noise interferometry sheds new light on the massive foundered lithosphere currently near the bottom of the mantle transition zone beneath southeastern Tibet.By integrating the novel seismic and pre-existing geochemical observations,we highlight a linkage between massive lithospheric delamination shortly after the onset of hard collision and activation of continental extrusion along the Ailao Shan-Re d River fault.This information provides critical insight into the early-stage evolution of the India-Asia collision in southeastern Tibet,which has significant implications for continental collision and its intracontinental response. | Jikun Feng Huajian Yao Ling Chen Weitao Wang | 2022 | National Science Review2022，9，4： | 7 |
| 15 | Impact of insect-resistant GM rice on pesticide use and farmers' health in China显示文摘The economic benefits of insect-resistant genetically modified(GM) crops have been well documented, but the impact of such crops and the consequent reduction in pesticide use on farmers' health remains largely unknown. Through the analysis of the data collected from the physical examination from farmers in China, we show that GM rice significantly reduces pesticide use and the resultant not only visible but also invisible adverse effects on farmers' neurological, hematological, and electrolyte system. Hence, the commercialization of GM rice is expected to improve the health of farmers in developing countries, where pesticide application is necessary to mitigate crop loss. | HUANG JiKun HU RuiFa QIAO FangBin YIN YanHong LIU HuaiJu HUANG ZhuRong | 2015 | Science China(Life Sciences)2015，58，5： | 6 |
| 16 | Infrared measurement of temperature field in coal gas desorption显示文摘In order to reveal the temperature change in coal gas desorption process,the temperature variation in coal gas desorption process under different particle sizes is analyzed with infrared thermal imager.The infrared video signals obtained by the experiment are processed with SAT.Then the infrared radiation signals are processed by EMD with Hilbert–Huang and the infrared radiation noise is effectively removed.The research results show that the desorption process,with the change of the temperature,is an endothermic process.The coal absorbs heat when the gas is desorbed and the temperature drops.The coal body temperature drop range is obviously related to coal particle size.The smaller the particle size is,the bigger the temperature drop becomes.The temperature variation curves in the process of coal gas desorption under different particle sizes are fitted,and they comply with the exponential function.The research results lay the theoretical and experimental foundation for non-contact prediction on working face of coal and gas outburst with infrared thermal image technology. | Liu Jikun Wang Cuixia He Xueqiu Li Shugang | 2014 | International Journal of Mining Science and Technology2014，24，1： | 6 |
| 17 | Monitoring the ionosphere based on the Crustal Movement Observation Network of China显示文摘The Global Navigation Satellite System(GNSS) is becoming important for monitoring the variations in the earth's ionosphere based on the total electron content(TEC) and ionospheric electron density(IED). The Crustal Movement Observation Network of China(CMONOC), which includes GNSS stations across China's Mainland, enables the continuous monitoring of the ionosphere over China as accurately as possible. A series of approaches for GNSS-based ionospheric remote sensing and software has been proposed and developed by the Institute of Geodesy and Geophysics(IGG) in Wuhan. Related achievements include the retrieval of ionospheric observables from raw GNSS data, differential code biases estimations in satellites and receivers, models of local and regional ionospheric TEC,and algorithms of ionospheric tomography. Based on these achievements, a software for processing GNSS data to determine the variations in ionospheric TEC and IED over China has been designed and developed by IGG. This software has also been installed at the CMONOC data centers belonging to the China Earthquake Administration and China Meteorological Administration. This paper briefly introduces the related research achievements and indicates potential directions of future work. | Yuan Yunbin Li Zishen Wang Ningbo Zhang Baocheng Li Hui Li Min Huo Xingliang Ou Jikun | 2015 | Geodesy and Geodynamics2015，6，2： | 5 |
| 18 | Levels of serum brain-derived neurotrophic factor in Type 2 diabetes mellitus patients with and without depressive symptoms显示文摘 | Jikun Wang Ming He | 2015 | Acta Biochimica et Biophysica Sinica2015，47，2： | 5 |
| 19 | Decreased serum brain-derived neurotrophic factor in Chinese patients with Type 2 diabetes mellitus显示文摘 | Ming He Jikun Wang | 2014 | Acta Biochimica et Biophysica Sinica2014，46，5： | 4 |
| 20 | Optimal carrier-smoothed-code algorithm for dual-frequency GPS data显示文摘Carrier-smoothed-code (CSC) algorithm is an e ective pseudorange multipath mitigation technique, which can alleviate the compu- tational burden and reduce the communication bandwidth needed for the transmission of GPS observations. This paper presents an improved Hatch lter and addresses the optimal CSC algorithm for dual-frequency GPS data based on the optimal parameter estimation theory. The smoothed observations have the same information content as that of the raw dual-frequency GPS data from which these are derived. Consequently, the optimal CSC algorithm is equivalent to the uncombined algorithm. Theoretical analyses show that the data precision of the optimal CSC algorithm is better than that of Hatch lter and its improved version. | Jianfeng Guo Jikun Ou Yunbin Yuan Haitao Wang | 2008 | Progress in Natural Science:Materials International2008，18，5： | 4 |
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