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A mechanically coupled MEMS filter with high-Q width extensional mode resonators

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Journal of Semiconductors 2024年第8期45卷 41-48页

作者： Wei Wang Wenli liu Junyuan zhao Bo Niu Zeyu Wu Yinfang Zhu {2. Yang Fuhua Yang institute of Semiconductors Chinese Academy of SciencesBeijing 100083China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

This work presents a novel radio frequency(RF)narrowband Si micro-electro-mechanical systems(MEMS)filter based on capacitively transduced slotted width extensional mode(WEM)*** flexibility of the plate leads to multiple modes near the target *** high Q-factor resonators of around 100000 enable narrow bandwidth filters with small size and simplified *** 1-wavelength and 2.wavelength WEMs were first developed as a pair of coupled modes to form a *** reduce bandwidth,two plates are coupled with aλ-length coupling *** 79.69 MHz coupled plate filter(CPF)achieved a narrow bandwidth of 8.8 kHz,corresponding to a tiny 0.011%.The CPF exhibits an impressive 3..84 dB stopband rejection and 7.82.dB insertion loss with near-zero passband *** summary,the RF MEMS filter presented in this work shows promising potential for application in RF transceiver front-ends.

关键词： MEMS narrowband filter mechanically coupling quality factor width extensional mode

A distributed hydrological model with its application to the Jinghe watershed in the Yellow River Basin

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Science China(Technological sciences) 2004年第z1期47卷 60-71页

作者： WANG Zhonggen1, ZHENG Hongxing1, liu Changming1, , WU Xianfeng2.2.& {3. Weimin{2. Key Laboratory of Water Cycle & Related Land Surface Processes, institute of {3. Science and natural resources research, chinese academy of sciences, beijing 100101, China 2. institute of Environmental Science, beijing Normal University, beijing 100875, China 3. Water resources Conservation Committee of Yellow River, Zhengzhou 450003. China Key Laboratory of Water Cycle & Related Land Surface Processes Institute of Geographic Science and Natural Resources Research Chinese Academy of Sciences institute of Environmental Science Beijing Normal University

For the purpose of water resources management in the Yellow River Basin with highly spatial difference, a daily distributed hydrological model was proposed, of which the determination of spatially-distributed parameters and model inputs processing were performed by means of GIS/RS. In the model, the computation of runoff yield was based on the topography index method and flow routing was modeled by Maskingum method. The operation of the model is followed by means of “command structure” technique based upon the topography of river network. A case study using the model was conducted for the Jinghe watershed, which locates at the middle Yellow River Basin. The simulation of the hydrological processes in 1996 has shown that water quantity balance errors were less than 5% and the Nash-Sutcliffe coefficient arrived at 0.7, indicating that the model structure is justifiable, and the precision of the model can satisfy the purpose of water resources management.

关键词： distributed hydrological model, structure and equation, GIS and RS, Jinghe Basin, Yellow River Basin.

Modeling the relationship of land use change and some geophysical indicators for the interlock area of farming and pasturing in China

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Journal of geographical sciences 2002年第4期12卷 397-404页

作者： DENG Xiangzheng, liu Jiyuan, ZHUANG Dafang, ZHAN Jinyan, zhao Tao(Inst. of {2. {3. and {3. resources research, CAS, beijing 100101, China) Inst. of geographic sciences and {2. {3. research CAS 北京 100101

This paper discusses land-use changes in the interlock area of farming and pasturing (IAFP) in northern China. It presents detailed analyses of land-use features in the IAFP, which are controlled by the macro geomorphic units and geophysical conditions-constraints or advantages. Additionally, it selects some indicators, according to the availability in acquiring and processing their quantitative data, to analyze the canonical correlations between the typical conversion of grassland and geophysical conditions. The preliminary study indicates that the physical conditions are of great advantages to the development of grassland. There exists significant correlation between land use change and some geophysical conditions.

关键词： land use driving force interlock area of farming and pasturing China

Method for Evaluating the Degrees of Land Use Sustainability of Mountainous County and its Application in Yunnan Province,China

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Journal of Mountain Science 2008年第2期5卷 98-112页

作者： YANG Zisheng liu Yansui TAO Wenxing XU Jingling zhao Qiaogui institute of Land ＆ resources and Sustainable Development Yunnan University of Finance and Economics Kunming 650221 China Institu te of geographic sciences and {2. {3. research Chinese Academy of Science Beijing 100101 China Department of Land ＆ resources of Yunnan Province Kunming 650224 China

The evaluation of sustainable land use is the key issue in the field of studying the sustainable land utilization. In general analysis, the sustainable land use is evaluated respectively from its ecological sustainability, economic sustainability and social sustainability in China and other countries in recent years. Although this evaluation is an important work, it seems insufficient and hard to comprehensively reflect the whole degree of land use sustainability. Thus, to make up this deficiency, this paper brings forward the evaluation indexes, which make it possible to quantitatively reflect the whole degree of land use sustainability, namely, the concept of ＂degrees of overall land use sustainability＂（Dos）, and research and measurement development of the method of and calculation in Dos. Taking the evaluation of the degree of land use sustainability in county regions of Yunnan Province as the actual example for analysis, results are basically as follows： 1） The degree of land use sustainability （Dos） is the ration index to organically and systematically integrate the degree of ecological friendliness （DeF）, the degree of economic viability （Dev） and the degree of social acceptability （Dsa）, able to comprehensively reflect the whole sustainability degree of regional land use 2. Based on the value of Dos, the grading system and standard for the sustainability of land use may be established and totally divided into five grades, namely, the high-degree sustainability, middle-degree sustainability, low-degree sustainability, conditional sustainability and non-sustainability. Meanwhile, the standard for distinguishing sustainability grades has also been confirmed so as to determine the nature of sustainability degrees in different grades. This makes the possibility for the combination of nature determination with ration in research result and provides with the scientific guideline and decision-making gist for better implementation of sustainable land use strategy

关键词： Land use degrees of overall sustainability evaluation method county level degrees of ecological friendliness degrees of economic viability degrees of social acceptability

A New Analytical Method of the Water resources Allocation in China

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A New Analytical Method of the Water Resources Allocation in...

Haplotype-resolved and chromosome-scale genomes provide insights into co-adaptation between the Amur tiger and Amur leopard

2.14年环境污染与大众健康学术会议

作者： Yanqi zhao1 2.3.Changming liu1 Ying YANG2.Hongxing ZHENG1 1{2. of geographic {3. and natural resources research CAS beijing 100101 China 2.2. of resources & Environment Henan Polytechnic University(HPU) Jiaozuo Henan 45400 China 3.raduate University of{12. beijing 100101 China

The paper introduces the Gini coefficient of economics as a new method of analyzing the inter-provincial allocation of water resources in *** calculated the Gini coefficient for selected indices based upon the statistical data for each province from 1997 to 2.08,respectively taking the population,GDP and the cultivated area as the basic matching ***,we proposed two novel indexes:the Dependence Coefficient to weigh the degree of reliance on the surface water or groundwater for the separated regions and the Burden Coefficient of water use to judge the efficiency and the level of fairness of water consumption by different *** results show that the allocation of water resources calculated per capita,per unit GDP and per unit area of arable land is very *** particular,some provinces located north of the Yangtze River lack water resources and strongly depend on the *** water efficiency is there lower than in other parts of ***,in order to alleviate the water stress in the northern provinces of the country,an improvement of the technological level of water resources exploitation and utilization and also the restructuring of the economic activity are necessary.

关键词： water resources allocation Gini coefficient Dependence Coefficient Burden Coefficient

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Zoological research 2024年第3期45卷 464-467页

作者： Hai-Meng Li Bo-Yang liu Min-Hui Shi Le Zhang Shang-Chen Yang Sunil Kumar Sahu Liang-Yu Cui Shan-Lin liu Nicolas Dussex Yue Ma Dan liu Wei-Yao Kong Hao-Rong Lu Yue {3. Love Dalén Huan liu Tian-Ming Lan Guang-Shun Jiang Yan-Chun Xu College of Wildlife and Protected Area Northeast Forestry UniversityHarbinHeilongjiang 150040China State Key Laboratory of Agricultural Genomics BGI ResearchShenzhenGuangdong 518083China College of Life sciences University of Chinese Academy of SciencesBeijing 100049China College of Life sciences Zhejiang UniversityHangzhouZhejiang 310058China BGI research WuhanHubei 430074China Department of Entomology College of Plant ProtectionChina Agricultural UniversityBeijing 100193China Centre for Palaeogenetics Svante Arrhenius väg 20CStockholm 10691Sweden Department of Zoology Stockholm UniversityStockholm 10691Sweden Department of Bioinformatics and Genetics Swedish Museum of Natural HistoryStockholm 10691Sweden Heilongjiang Siberian Tiger Park HarbinHeilongjiang 150000China Jinlin Provincial academy of Forestry Science ChangchunJilin 130033China China National GeneBank BGI ResearchShenzhenGuangdong 518120China Guangdong Provincial Key Laboratory of Genome Read and Write BGI ResearchShenzhenGuangdong 518083China BGI Life Science Joint research Center Northeast Forestry UniversityHarbinHeilongjiang 150040China Feline research Center of National Forestry and Grassland Administration College of Wildlife and Protected AreaNortheast Forestry UniversityHarbinHeilongjiang 150040China National Forestry and Grassland Administration research Center of Engineering Technology for Wildlife Conservation and Utilization HarbinHeilongjiang 150040China

DEAR EDITOR,Big cats,such as Amur tigers(Panthera tigris altaica)and Amur leopards(*** orientalis),are apex predator and have evolved specialized traits for hunting and carnivory(Moya et al.,2.2.),thus playing a crucial role in maintaining biodiversity and ecosystem integrity by regulating prey-predator ***,human-induced pressures,habitat fragmentation,and environmental alterations have restricted these species in small and isolated ***,all extant big cats are categorized as endangered or threatened according to their conservation *** tigers and Amur leopards share overlapping geographic ranges,habitats,and certain prey species in the forests of Northeast Asia(Jiang et al.,2.15).To reduce interspecies conflict,these carnivores exhibit differentiated dietary and temporal *** tigers predominantly prey on large ungulates,while Amur leopards hunt small to medium-sized animals(Sugimoto et al.,2.16).Additionally,they occupy different temporal niches,with tigers being active at night and leopards more active during the *** spatial and temporal niche partitioning,interspecific competition between these two species is ***,benefiting from their greater size,have a competitive advantage over leopards,which can manifest in occasional leopard predation by tigers and declines in leopard populations with increasing tiger density(Jiang et al.,2.15).Tigers also displace leopards from marginal habitats in nature reserves where they coexist.

关键词： habitat Panthera resolved

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GIS支持下不同坡度的土壤侵蚀特征分析

水土保持学报 2002年第6期16卷 46-49页

作者：杨存建刘纪远张增祥周全斌赵晓丽四川师范大学遥感与应用研究中心四川成都610066 中国科学院地理科学与资源研究所北京100101 中国科学院遥感应用研究所北京100101

利用地理信息系统技术对不同坡度等级情况下的土壤侵蚀特征进行了分析。首先,利用地理信息系统软件从DEM数据中产生坡度数据,将其分级为6个等级。然后与土壤侵蚀数据集进行叠加统计分析,从而得到不同坡度等级情况下的土壤侵蚀特征。本... 详细信息

利用地理信息系统技术对不同坡度等级情况下的土壤侵蚀特征进行了分析。首先,利用地理信息系统软件从DEM数据中产生坡度数据,将其分级为6个等级。然后与土壤侵蚀数据集进行叠加统计分析,从而得到不同坡度等级情况下的土壤侵蚀特征。本文研究表明:(1)坡度等级从2.5级,轻度以上水蚀所占百分比逐渐降低。(2.在所有坡度等级上,轻度以上风蚀所占百分比均在86.8%以上。在第2.度等级上,风蚀综合指数最高,而在第5坡度等级上,风蚀综合指数最低。(3.冻融侵蚀综合指数的最高值出现在第3.度等级上,其最低值出现在第6坡度等级上。(4)在各个坡度等级上,均以水蚀为主,均在46%以上,其最高值为73.8%,出现在第4坡度级上。此外,在第1坡度级上,风蚀占次优势,而在第2.6坡度等级上,冻融占次优势。(5)坡度等级在1,2.3.上,其轻度侵蚀所占百分比和土壤侵蚀综合指数均相对较高,而在坡度等级4,5和6级上,轻度侵蚀所占百分比和土壤侵蚀综合指数均相对较低。这主要是由于在坡度等级较低的情况下,人为活动比较多,土地利用程度较高,对植被和土壤的破坏较大,从而导致这种反常现象。

关键词：地理信息系统坡度等级土壤侵蚀

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地球观测知识枢纽:内涵、关键技术与展望

遥感学报 2024年第6期28卷 1375-1394页

作者：赵利民苗晨邢进李国庆侯宇葵刘闯李家国陈兴峰刘军杨健周翔顾行发中国科学院空天信息创新研究院北京100094 遥感卫星应用国家工程研究中心北京100094 国家航天局航天遥感论证中心北京100094 国家遥感中心北京100036 国防科工局重大专项工程中心北京100101 国家对地观测科学数据中心北京100094 中国空间技术研究院钱学森空间技术实验室北京100094 中国科学院地理科学与资源研究所北京100101

智能化地共享和复用地球观测应用实践所形成的知识,有序促进应用要素的高通量流动,是激活和释放地球观测系统效能的关键。地球观测知识枢纽EOKH(Earth Observation Knowledge Hub)将分散的应用要素有机耦合,形成专题知识集合的协同设计... 详细信息

智能化地共享和复用地球观测应用实践所形成的知识,有序促进应用要素的高通量流动,是激活和释放地球观测系统效能的关键。地球观测知识枢纽EOKH(Earth Observation Knowledge Hub)将分散的应用要素有机耦合,形成专题知识集合的协同设计与吞吐能力,是地球观测成果治理与智能服务的研究前沿。针对地球观测组织GEO(Group on Earth Observations)发展GEO知识枢纽GKH(GEO Knowledge Hub)得到的启示,结合地球观测知识本体研究最新进展,系统解析了EOKH的内涵与特征,梳理了发展EOKH的技术需求与挑战,分析存在的关键问题及其应对策略。在此基础上,提出了EOKH系统架构原型,结合地球观测知识包转移复用和知识推理两个EOKH典型应用场景进行了原理实现与概念验证。最后,就如何促进地球观测知识“人—机—物”要素的协同共生,提出了中国发展EOKH的相关认识与思考。探索“人在回路”的高通量知识协同生产与转移技术,以及“知识驱动”的成果复用技术,是提升地球观测隐性知识可解释性、促进EOKH服务质量与发展力的必要举措。

关键词：遥感知识枢纽地球观测本体知识包知识复用人—机—物人在回路

A study of virtual land trade between China and ASEAN based on material flow analysis model

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Ecological Economy 2008年第4期4卷 386-393页

作者： zhao jinling {2. {3. Yang Aqiang Yu Bohua Global Change Information and research Center Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 P R. China Graduate School Chinese Academy of Sciences Beijing 100039. P R. China College of resources sciences and Technology Beijing Normal University Beij＇ing 100875. P. R. China

In this paper,based on the material flux analysis model（MFA） and its corresponding theories and algorithms of ＂virtual land＂ virtual land contents of five primary agricultural products are calculated and＂Virtual land trade＂hidden in those imported and exported products are also obtained through analyzing the primary agricultural product trade between China and ASEAN. In the process of calculationl following the thought of Changing agricultural products to ＂Virtual land trade＂land content, trade condition and spatiai distribution of agricultural products Were integratedly considered. indicate that China exported 73.057 km^2.of virtual land area to ASEAN by tea, vegetables; maize and grain, ASEAN exported： 57.3.2.km^2.to China by {3. rubber from 2.02.to 2.05. It obvious; that china has lost 15,72. km^2.arable land through agricultural product trade, Additionally, in order to process： of calculation Virtual land trade, Thailand taker as an example to analyze its international trade of rice and Wheat from 1991 to 2.05 and Calculate their ＂Virtual land trade＂ 2.01 through 2.05. According to and calculation, it is not difficult to conclude that ＂Virtual land trade＂ very important and could be used for China to guide agricultural export or import Structure and maintain Sustainable use of land resources.

关键词： Land resources Virtual land Virtual land trade ASEAN