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毫米波雷达信号功率电平测量

环境技术 2024年第4期42卷 106-115页

作者：陈辉邵鄂米进才张少勇李帅男黎亮文工业化信息化部电子第五研究所广州510610 电子科技大学(深圳)高等研究院深圳518000

FMCW Chirp是毫米波雷达主要应用的调频技术。各个国家和地区的法规和标准均规定了FMCW Chirp信号的峰值和平均值功率电平限值。为了准确测量FMCW Chirp信号的功率电平,需要确定FMCW Chirp信号的时域特性,采用合适的测量仪器,并考虑测... 详细信息

FMCW Chirp是毫米波雷达主要应用的调频技术。各个国家和地区的法规和标准均规定了FMCW Chirp信号的峰值和平均值功率电平限值。为了准确测量FMCW Chirp信号的功率电平,需要确定FMCW Chirp信号的时域特性,采用合适的测量仪器,并考虑测量仪器对FMCW Chirp信号的响应特性,同时进行合适的扫描参数设置,才能获得具有较小误差的测量结果。本文还给出了测量仪器设置的一般性指引。

关键词：毫米波雷达调频连续波功率测量

A Set of SCAR Markers Efficiently Differentiating Hybrid Rice

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Rice science 2012年第1期19卷 14-20页

作者： LI Shu-jing XIE Hong-wei QIAN Ming-juan CHEN Guang-hui LI shao-qing ZHU ying-guo State Key Laboratory of Hybrid Rice Key Laboratory for Research and Utilization of Heterosis in lndica Rice Ministry of Agriculture Engineering Research Center for Plant Biotechology and Germplasm Utilization of Ministry of Education College of Life Sciences Wuhan University Wuhan 430072 China Bangbu Medical College Bangbu 233030 China College of Plant Science Hunan Agricultural University Changsha 410128 China

Molecular markers have been widely used in crop genetic improvement, seed test and genetic mapping. Of which, sequence characterized amplified region （SCAR） markers are particularly popular for its diversity, stable reproducibility, and suitability for analyzing large number of samples. In this study, 500 random amplified polymorphic DNA （RAPD） primers were tested, and a set of SCAR markers comprising 37 pairs of loci-specific primers were developed from the DNA fragments ranging from 300 to 1000 bp which correspond to the stable, distinctive RAPD banding patterns. Using these SCAR markers, 59 hybrid rice combinations were assessed and distinguished into 58 subgroups at the similarity coefficient of 0.97 in a genetic clustering tree based on the allele diversities of the SCAR markers. Furthermore, 13 hybrid rice combinations were reassayed with 40 randomly selected simple sequence repeat （SSR） markers to evaluate the effectiveness of these SCAR markers. SSR markers produced similar results to SCAR markers as the 13 hybrid rice combinations were completely separated at the similarity coefficient of 0.91 in the clustering tree established from SSR patterns. Taken together, SCAR markers prove to be effective tools for identifying and differentiating hybrid rice combinations.

关键词： hybrid rice molecular marker sequence characterized amplified region variety identification

Layout Planning Technology of Cellular Manufacturing System Based on Process Interconnection Analysis

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Chinese Journal of Mechanical Engineering 2011年第6期24卷 1035-1044页

作者： CHEN Huawei WANG Aimin NING Ruxin shao Canxia Digital Design and Manufacturing Laboratory Beijing Institute of TechnologyBeijing 100081China

With sustaining change of production mode,layout planning is no longer a thing built once for *** layout(CL) is becoming a hotspot in the research field of manufacturing system *** researches on layout planning are mainly concentrating on aspects of layout arithmetic,style and evaluation,*** seldom efforts are paid to CL and its specific problems as cell formation(CF),equipment sharing and CL *** problem analyzing of layout in cellular manufacturing system(CMS),research approach of cell formation,interactive layout and layout analysis threaded with process interconnection relationship(PIR) is *** key technologies in CL like CF technology based on similarity analysis of part processes,interactive visual layout technology,layout evaluation technology founded on PIR analysis and algorithm of cell equipment sharing are put *** the background of one enterprise which encounters problems of low utility of key equipments and disperse material logistic,an example of four-cell layout is *** CL adjustment and analysis results show that equipment with high level of sharing degree should be disposed around the boundary of its main cell,and be near to other sharing cells as possible; process route should be centralized by all means,so equipment adjustment is to be implemented along direction that route intersection can be decreased; giving consideration to the existence of discrete cell,logistic route and its density should be centralized to cells *** proposed research can help improve equipment utility and material logistic efficiency of CL,and can be popularized to other application availably.

关键词： cellular manufacturing system, layout planning process interconnection relationship cell formation equipment sharing interactive layout

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Space Gene

China City Planning Review 2022年第3期31卷 6-14页

作者： Duan Jin shao Runqing Lan Wenlong Liu Jinhua Jiang ying Li Min(Translated) Tang Yan(Proofread) School of Architecture Southeast UniversityNanjingP.R.China Urban Planning Society of China the Standardization Working Committee Urban Planning Society of China Urban Design Academic Committee NanjingP.R.China Urban Planning and Design Institute of Southeast University NanjingP.R.China Southeast University NanjingP.R.China National University of Singapore NanjingP.R.China 不详

Based on typo-morphological studies,this paper proposes the concept of “space gene” from the perspective of urban spatial development ***,space gene refers to a unique and relatively stable pattern of spatial organization formed as a result of long-term interaction among the three dimensions:urban space,natural environment,and *** conveys distinctive characteristics of different regions and contributes to a unique city identity and a harmonious relationship among the three *** paper points out that urban planning and design can be localized through the identification-analysis-guidance process of space genes,avoiding both the design scheme that does not respect culture and nature and the practice that a unified model is adopted to create same images in different cities,as well as prompting the directional turn of urban planning and design approaches from space form creation to space gene *** provides an effective design path for a win-win result among urban development,natural protection,and cultural ***,the paper discusses the prospect of the Space GenBank Project.

关键词： space gene spatial development theory typo-morphology sustainable development spatial interaction cultural inheritance locality

Original article Relationship between perinatal characteristics and later activities of daily living in Chinese elderly people

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Chinese Medical Journal 2009年第9期122卷 1015-1019页

作者： XU Tao ZHANG Zhen-xin HAN shao-mei XIAO Xin-hua GONG Xiao-ming CHEN Xia HU Hong-tao WANG Zi-shi LIU Ai-min Department of Epidemiology and Statistics Institute of Basic Medical Sciences Chinese Academy of Medical Sciences & School of Basic Medicine Peking Union Medical College Beijing 100005 China Department of Neurology Peking Union Medical College Hospital Chinese Academy of Medical Sciences Beijing 100730 China Department of Endocrinology Peking Union Medical College Hospital Chinese Academy of Medical Sciences Beijing 100730 China Department of Obstetrics Peking Union Medical College Hospital Chinese Academy of Medical Sciences Beijing 100730 China Case Registry Office Peking Union Medical College Hospital Chinese Academy of Medical Sciences Beijing 100730 China Department of Cardiology Peking Union Medical College Hospital Chinese Academy of Medical Sciences Beijing 100730 China

Background There are no reports on the association between perinatal characteristics and comprehensive physical function in Chinese elderly people. In this study, we traced 875 subjects who were born at the Peking Union Medical College Hospital （PUMCH） of China from 1921 to 1941. The purpose of this study was to determine the effects of perinatal characteristics on activities of daily living （ADL） function in the geriatric period.Methods Birth data of 875 subjects were obtained from obstetric birth records of PUMCH. Adulthood data collection was conducted in the outpatient clinics of PUMCH. During the clinic visits, trained research staff administered physical examinations, activities of daily living scale and a demographic questionnaire. ADLs of all subjects were assessed with the activities of daily living scale.Results There were 101 subjects whose ADL function was limited and the rate of ADL limitation was 11.5%. Binary logistic regression analyses results showed that the main influencing factors of ADL were age, maternal age at birth, occupation, daily exercise and chronic disease. Subjects whose maternal age at their birth exceeded 35 years were at 2.202 times （1.188-4.083） greater risk of ADL limitation when we applied multivariate logistic rearession models.Conclusions This study validated the relationship between perinatal characteristics and ADL in the geriatric period. An older maternal age at birth could predict a higher ADL limitation rate in the geriatric period.

关键词： perinatal epidemiology geriatrics activities of daily living physical activity maternal age

Insights into metals in individual fine particles from municipal solid waste using synchrotron radiation-based micro-analytical techniques

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Journal of Environmental Sciences 2015年第1期27卷 298-308页

作者： Yumin Zhu Hua Zhang Liming shao Pinjing He State Key Laboratory of Pollution Control and Resources Reuse Tongji University Institute of Waste Treatment and Reclamation Tongji University Research and Training Center on Rural Waste Management Ministry of Housing and Urban–Rural Development of P.R. China

Excessive inter-contamination with heavy metals hampers the application of biological treatment products derived from mixed or mechanically-sorted municipal solid waste（MSW）. In this study, we investigated fine particles of 〈 2 mm, which are small fractions in MSW but constitute a significant component of the total heavy metal content, using bulk detection techniques. A total of 17 individual fine particles were evaluated using synchrotron radiation-based micro-X-ray fluorescence and micro-X-ray diffraction. We also discussed the association, speciation and source apportionment of heavy metals. Metals were found to exist in a diffuse distribution with heterogeneous intensities and intense hot-spots of 〈 10 μm within the fine particles. Zn–Cu, Pb–Fe and Fe–Mn–Cr had significant correlations in terms of spatial distribution. The overlapped enrichment, spatial association, and the mineral phases of metals revealed the potential sources of fine particles from size-reduced waste fractions（such as scraps of organic wastes or ceramics） or from the importation of other particles. The diverse sources of heavy metal pollutants within the fine particles suggested that separate collection and treatment of the biodegradable waste fraction（such as food waste） is a preferable means of facilitating the beneficial utilization of the stabilized products.

关键词： Municipal solid waste Fine particle Synchrotron radiation Micro-analytical technique Metal

Enhanced anaerobic digestion and sludge dewaterability by alkaline pretreatment and its mechanism

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Journal of Environmental Sciences 2012年第10期24卷 1731-1738页

作者： Liming shao Xiaoyi Wang Huacheng Xu Pinjing He State Key Laboratory of Pollution Control and Resources Reuse College of Environmental Science and EngineeringTongdi UniversityShanghai 200092China

To investigate the influences of alkaline pretreatment on anaerobic digestion （AD） and sludge dewaterability after AD, waste activated sludge was adjusted to different pH values （8, 9, 10, 1 1, 12） and placed at ambient temperature for 24 hr. The samples were then adjusted to the initial pH and subjected to 25 days of AD. The results showed that, when compared with the control （pH 6.8）, total suspended solids （TSS） and volatile suspended solids （VSS） reduction following pretreatment at pH 9-11 increased by 10.7%-13.1% and 6.5%- 12.8%, respectively, while biogas production improved by 7.2%-15.4%. Additionally, significant enhancement of sludge dewaterability after AD occurred when pretreatment at pH 8-9 was conducted. The proteins and carbohydrates transferred from the pellet and tightly bound extracellular polymeric substances （TB-EPS） fractions to the slime and loosely bound EPS （LB-EPS） fractions after pretreatment and during the AD process, and the concentrations of proteins and carbohydrates in the slime fraction had a good linear relationship with the normalized capillary suction time （CST）. During the AD process, the normalized CST was positively correlated with the organic materials in the loosely bound fraction of the sludge matrix （R2/〉 0.700, p 〈 0.01）, while it was negatively correlated with the organic materials in the tightly bound fraction （R2≥ 0.702, p 〈 0.01）. These results suggest that alkaline pretreatment could break the EPS matrix and release inner organic materials, thus influencing the efficiency of the AD process and dewaterability after AD.

关键词： waste activated sludge alkaline pretreatment digestibility dewaterability extracellular polymeric substances

Corrosion inhibition of stainless steel by a sulfate-reducing bacteria biofilm in seawater

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International Journal of Minerals,Metallurgy and Materials 2012年第8期19卷 717-725页

作者： Fu-shao Li Mao-zhong An Dong-xia Duan School of Chemistry and Chemical Engineering Qujing Normal University Qujing 655011 China State Key Laboratory for Marine Corrosion and Protection Qingdao 266071 China Chemical Engineering School Harbin Institute of Technology Harbin 150001 China

Corrosion inhibition of stainless steel due to a sulfate-reducing bacteria （SRB） biofilm in seawater was studied. By atomic force microscopy, a layer of fish-scale-like biofilm was found to form as stainless steel coupons were exposed to the culture media with SRB, and this biofilm grew more and more compact. As a result, coupons＇ surface under the biofilm turned irregular less slowly than that exposed to the sterilized culture media. Then, physicoelectric characteristics of the electrode/biofilrn/solution interface were investigated by electro- chemical impedance spectroscopy （EIS）, and the coverage of the biofilm as well as the relative irregularity of coupons＇ surface was also re- corded by EIS spectra.. Finally, anodic cyclic polarization results further demonstrated the protective property of the biofilm. Therefore, in es- timation of SRB-implicated corrosion of stainless steel, not only the detrimental SRB metabolites but also the protective SRB biofilm as well should be taken into account.

关键词： stainless steel corrosion prevention microbiology microorganisms biofilms electrochemistry

A New Distributed Localization Scheme for Wireless Sensor Networks

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自动化学报 2008年第3期34卷 344-348页

作者： KUANG Xing-Hong shao Hui-He FENG Rui Department of Automation Shanghai Jiao Tong UniversityShanghai 200240P.R.China College of Engineering Science ＆ Technology Shanghai Fisheries UniversityShanghai 200090P.R.China Department of Electrical and Computer Engineering Fudan UniversityShanghai 200433P.R.China

在无线传感器网络(WSN ) 的节点本地化是被对待一功能目标在纸从一个新奇观点追踪双。与在 WSN 的传统的追踪问题不同，使用静态的地点商品节点估计动人的目标，活动节点被用来帮助未知节点精确地发现他们的位置。一个新节点本地化计划... 详细信息

在无线传感器网络(WSN ) 的节点本地化是被对待一功能目标在纸从一个新奇观点追踪双。与在 WSN 的传统的追踪问题不同，使用静态的地点商品节点估计动人的目标，活动节点被用来帮助未知节点精确地发现他们的位置。一个新节点本地化计划虚拟烽火精力比率本地化(VB-ERL ) 和它为 WSN 的精炼被介绍。在计划，活动节点基于 Gauss-Markov 活动性模型搬到监视者地并且周期性地广播信息包。每个静态的未知节点在它的察觉到的范围收到虚拟烽火和精力，并且由发现一套超球面的交叉估计它的地点。模拟结果证明建议计划是有效的。

关键词：无线传感器网络节点定位虚拟信号分布式定位配置