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| 1 | Remote sensing-based artificial surface cover classification in Asia and spatial pattern analysis显示文摘Artificial surfaces, characterized with intensive land-use changes and complex landscape structures, are important indicators of human impacts on terrestrial ecosystems. Without high-resolution land-cover data at continental scale, it is hard to evaluate the impacts of urbanization on regional climate, ecosystem processes and global environment. This study constructed a hierarchical classification system for artificial surfaces, promoted a remote sensing method to retrieve subpixel components of artificial surfaces from 30-m resolution satellite imageries(Globe Land30) and developed a series of data products of high-precision urban built-up areas including impervious surface and vegetation cover in Asia in 2010. Our assessment, based on multisource data and expert knowledge, showed that the overall accuracy of classification was 90.79%. The mean relative error for the impervious surface components of cities was 0.87. The local error of the extracted information was closely related to the heterogeneity of urban buildings and vegetation in different climate zones. According to our results, the urban built-up area was 18.18×104 km2, accounting for 0.59% of the total land surface areas in Asia; urban impervious surfaces were 11.65×104 km2, accounting for 64.09% of the total urban built-up area in Asia. Vegetation and bare soils accounted for 34.56% of the urban built-up areas. There were three gradients: a concentrated distribution, a scattered distribution and an indeterminate distribution from east to west in terms of spatial pattern of urban impervious surfaces. China, India and Japan ranked as the top three countries with the largest impervious surface areas, which respectively accounted for 32.77%, 16.10% and 11.93% of the urban impervious surface area of Asia. We found the proportions of impervious surface and vegetation cover within urban built-up areas were closely related to the economic development degree of the country and regional climate environment. Built-up areas in developed countries had relatively low impervious surface and high public green vegetation cover, with 50–60% urban impervious surfaces in Japan, South Korea and Singapore. In comparison, the proportion of urban impervious surfaces in developing countries is approaching or exceeding 80% in Asia. In general, the composition and spatial patterns of built-up areas reflected population aggregation and economic development level as well as their impacts on the health of the environment in the sub-watershed. | KUANG WenHui CHEN LiJun LIU JiYuan XIANG WeiNing CHI WenFeng LU DengSheng YANG TianRong PAN Tao LIU AiLin | 2016 | Science China Earth Sciences2016，59，9： | 12 |
| 2 | Soil Microbial Community and Enzyme Activity Responses to Herbaceous Plant Expansion in the Changbai Mountains Tundra, China显示文摘As one of the most sensitive regions to global climate change, alpine tundra in many places around the world has been undergoing dramatic changes in vegetation communities over the past few decades.Herbaceous plant species in the Changbai Mountains area have significantly expanded into tundra shrub communities over the past 30 yr.Soil microbial communities, enzyme activities, and soil nutrients are intertwined with this expansion process.In order to understand the responses of the soil microbial communities to such an expansion, we analyzed soil microbial community structures and enzyme activities in shrub tundra as well as areas with three different levels of herbaceous plant expansion.Our investigation was based on phospholipid fatty acid(PLFA) analysis and 96-well microtiter plates.The results showed that herbs have expanded greatly in the tundra, and they have become the dominant species in herbaceous plant expansion areas.There were differences for community composition and appearance among the shrub tundra and the mild expansion, moderate expansion, and severe expansion areas.Except for soil organic matter, soil nutrients were increased in herbaceous plant expansion areas, and the total nitrogen(TN), total phosphorus(TP), available nitrogen(AN), and available phosphorus(AP) were greatest in moderate expansion areas(MOE), while soil organic matter levels were highest in the non-expanded areas(CK).The total soil PLFAs in the three levels of herbaceous plant expansion areas were significantly higher than those in the non-expanded areas, and total soil PLFAs were highest in the moderately expanded area and lowest in the severely expanded area(SEE).Bacteria increased significantly more than fungi and actinomycetes with herbaceous plant expansion.Soil hydrolase activities(β-1,4-glucosidase(βG) activity, β-1, 4-N-acetylglucosaminidase(NAG) activity, and acid phosphatase(aP) activity) were highest in MOE and lowest in the CK treatment.Soil oxidase activities(polyphenol oxidase(PPO) activities and peroxidase(PER) activities) were also highest in MOE, but they were lowest in the SEE treatment.The variations in total soil PLFAs with herbaceous plant expansion were mostly correlated with soil organic matter and available phosphorus concentrations, while soil enzyme activities were mostly correlated with the total soil nitrogen concentration.Our results suggest that herbaceous plant expansion increase the total soil PLFAs and soil enzyme activities and improved soil nutrients.However, soil microorganisms, enzyme activity, and nutrients responded differently to levels of herbaceous plant expansion.The soil conditions in mild and moderate expansion areas are more favorable than those in severe expansion areas. | JIN Yinghua ZHANG Yingjie XU Zhiwei GU Xiaonan XU Jiawei TAO Yan HE Hongshi WANG Ailin LIU Yuxia NIU Liping | 2019 | Chinese Geographical Science2019，29，6： | 4 |
| 3 | Comparative Assessment of Tundra Vegetation Changes Between North and Southwest Slopes of Changbai Mountains, China, in Response to Global Warming显示文摘Vegetation in high altitude areas normally exhibits the strongest response to global warming. We investigated the tundra vegetation on the Changbai Mountains and revealed the similarities and differences between the north and the southwest slopes of the Changbai Mountains in response to global warming. Our results were as follows: 1) The average temperatures in the growing season have increased from 1981 to 2015, the climate tendency rate was 0.38℃/10 yr, and there was no obvious change in precipitation observed. 2) The tundra vegetation of the Changbai Mountains has changed significantly over the last 30 years. Specifically, herbaceous plants have invaded into the tundra zone, and the proportion of herbaceous plants was larger than that of shrubs. Shrub tundra was transforming into shrub-grass tundra. 3) The tundra vegetation in the north and southwest slopes of the Changbai Mountains responded differently to global warming. The southwest slope showed a significantly higher degree of invasion from herbaceous plants and exhibited greater vegetation change than the north slope. 4) The species diversity of plant communities on the tundra zone of the north slope changed unimodally with altitude, while that on the tundra zone of the southwest slope decreased monotonously with altitude. Differences in the degree of invasion from herbaceous plants resulted in differences in species diversity patterns between the north and southwest slopes. Differences in local microclimate, plant community successional stage and soil fertility resulted in differential responses of tundra vegetation to global warming. | JIN Yinghua ZHANG Yingjie XU Jiawei TAO Yan HE Hongshi GUO Meng WANG Ailin LIU Yuxia NIU Liping | 2018 | Chinese Geographical Science2018，28，4： | 3 |
| 4 | Milliampere He^2+ beam generator using a compact GHz ECRIS显示文摘Multi-charged helium ion beam He2+ is useful for helium accelerator to obtain a higher energy with lower cost and for deuterium accelerator to avoid neutron activation during machine commissioning.An attempt to generate milliampere multi-charged helium He2+ion beam with a 2.45 GHz electron cyclotron resonance ion source(ECRIS) was tested recently.A design using a specfic permanent magnet 2.45 GHz ECRIS(PMECRIS) source(ERCIS) is reported and the He2+beam production ability is described.With this source,we produced a total helium beam of 40 mA at 40 kV with 180 W of net microwave power and a gas flow of less than 0.5 sccm.At steady state the He2+beam intensity is 4.4 mA,that being the fraction of multi-charged helium ion beam is at approximately 11%. | REN HaiTao PENG ShiXiang XU Yuan ZHAO Jie CHEN Jia ZHANG Tao ZHANG AiLin GUO ZhiYu CHEN JiaEr | 2013 | Science China(Physics,Mechanics & Astronomy)2013，56，10： | 2 |
| 5 | Milliampere He2+ beam generator using a compact GHz ECRIS显示文摘 | Haitao Ren Shixiang Peng Yuan Xu Jie Zhao Jia Chen Tao Zhang Ailin Zhang Zhiyu Guo and Jiaer Chen | | SCIENCE CHINA Physics Mechanics & Astronomy 00，，： | 1 |
| 6 | A bioinformatic evaluation of potential allergenicity of 85 candidate genes in transgenic organisms显示文摘The potential of genetically modified organisms(GMOs) to increase allergenicity or predispositions to allergies has attracted much attention.An approach that will properly and holistically evaluate the allergenicity of GMOs is yet to be found.Here,85 transgenes that have been reported in both international and domestic studies during recent years are summarized case by case;49 of the transformed genes were from plant sources and 36 were from animal sources.EVALLERTM,a web server for the in silico assessment of potential protein allergenicity,was used to evaluate the potential of the transgenic proteins as allergens.The biomedical journals listed in Highwire(http://gffzzd58bc32f34884012hbqb5knwq5ukq6b55.ffgz.tsg.suse.edu.cn/) were searched and reviewed to decipher whether any of the transformed genes were linked to allergenicity or human health.The EVALLER analysis identified 5 allergenic genes,whilst our literature review found 11 genes that were either related to allergic cases or to clinical adverse events;all 16 of these genes have been used in GMOs.The analysis pathway that we have developed can help guide the selection of genes to be used in genetic modification.The pathway also provides a paradigm for allergenicity analysis of transgene candidates. | ZOU ZeHong HE Ying RUAN Lin SUN BaoQing CHEN HuiFang CHEN De LIU ShiMing YANG XiaoGuang TAO AiLin | 2012 | Chinese Science Bulletin2012，57，15： | 1 |
| 7 | Based on the efficiency coeffi- cient-BP neural network study of the risk of early warning 显示文摘 | Tao Yonghong Qi Ailin | 2009 | Management Science and Engineering2009，3，3： | 1 |
| 8 | A Simple BCH Decoder for NoC Interconnects and SoC Buses显示文摘Network on a chip(NoC)uses packetswitched network to implement interconnections in System on chip(SoC).In SoC design,performance and energy efficiency are respectively the first and second priorities,and optimal on-chip communication should decrease the power consumption and area overhead.In this work,a simplified BCH codec is proposed for reliable communication in NoC and SoC.It performs BCH error corrections without Berlekamp’s algorithm,only using reduced syndrome bits to determine error patterns.The error locations can be found by looking up tables,by which the possible errors are directly corrected.Only one matrix product and one ROM access are required in the BCH decoder.The proposed(20,8,2)and(31,16,3)decoders in the paper can be easily applied for error corrections of interconnects and buses for NoC and SoC.It is also beneficial to correct data lines without length definition and control lines without storage. | WU Tao YANG Ailin | 2021 | Chinese Journal of Electronics2021，30，3： | 1 |
| 9 | Based on the Efficiency Coefficient-BP Neural Network Study of the Risk of Early Warning显示文摘 | Yonghong TAO Ailin QI | 2009 | Management Science and Engineering2009，，3： | 1 |
| 10 | Multiple charge ion beam generation with a 2.45 GHz electron cyclotron resonance ion source显示文摘Multiple charge ions (MCIs) are necessary for increasing the output energy of particles in accelerators. In general, MCI beams are largely produced by electron beam ion source (EBIS) [1], laser ion source (LIS) [2], or high-frequency (mostly >5 GHz) electron cyclotron resonance (ECR) ion source [3]. Among these, only ECR ion source can operate in the continuous wave (CW) mode, while EBIS and LIS only support pulses. In addition, ECR ion source with lower frequency (mostly 2.45 GHz) are required primarily for generating single charge state ions, because the corresponding ECR field (875 Gs) is not sufficiently strong for MCI generation [4]. | Yuan Xu ShiXiang Peng HaiTao Ren JiaMei Wen AiLin Zhang Tao Zhang JingFeng Zhang WenBin Wu ZhiYu Guo JiaEr Chen | 2017 | Science China(Physics,Mechanics & Astronomy)2017，60，6： | 0 |
| 11 | Plasma parameter diagnosis using hydrogen emission spectra of a quartz-chamber 2.45 GHz ECRIS at Peking University显示文摘A quartz-chamber 2.45 GHz electron cyclotron resonance ion source(ECRIS) was designed for diagnostic purposes at Peking University [Patent Number: ZL 201110026605.4]. This ion source can produce a maximum 84 m A hydrogen ion beam at 50 k V with a duty factor of 10%. The root-mean-square(RMS) emittance of this beam is less than 0.12π mm mrad. In our initial work,the electron temperature and electron density inside the plasma chamber had been measured with the line intensity ratio of noble gases. Based on these results, the atomic and molecular emission spectra of hydrogen were applied to determine the dissociation degree of hydrogen and the vibrational temperature of hydrogen molecules in the ground state, respectively. Measurements were performed at gas pressures from 4×10^(-4) to 1×10^(-3) Pa and at input peak RF power ranging from 1000 to 1800 W. The dissociation degree of hydrogen in the range of 0.5%-10% and the vibrational temperature of hydrogen molecules in the ground state in the range of 3500-8500 K were obtained. The plasma processes inside this ECRIS chamber were discussed based on these results. | WenBin Wu HaiTao Ren ShiXiang Peng Yuan Xu JiaMei Wen Tao Zhang JingFeng Zhang AiLin Zhang Jiang Sun ZhiYu Guo JiaEr Chen | 2018 | Science China(Physics,Mechanics & Astronomy)2018，61，4： | 0 |
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