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Report on Childhood Obesity in China (1) Body Mass Index Reference for Screening Overweight and Obesity in Chinese School-age Children 被引量:57
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作者 COOPERATIVE STUDY ON CHILDHOOD OBESITY WORKING GROUP ON OBESITY IN CHINA (WGOC) 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2005年第6期390-400,共11页
Purpose To establish and propose a national body mass index (BMI) reference for screening overweight and obesity in Chinese school-age children and adolescents. Methods 2000 CNSSCH (Chinese National Survey on Stude... Purpose To establish and propose a national body mass index (BMI) reference for screening overweight and obesity in Chinese school-age children and adolescents. Methods 2000 CNSSCH (Chinese National Survey on Students Constitution and Health) data, including 216 620 primary and secondary school students aged 7 to 18 years old, were used as a reference population. Compared with those of the NCHS intematioanl reference, three temporary sets of cut-off BMI were proposed by testing different combinations of P85, P90, and P95. When physiological and biochemical measures between and among “obesity” “overweight”, and “normal weight” groups were taken into consideration, set Ⅱ was selected to be the most appropriate one. The sex-age-specific curves were then plotted and smoothed by using B-spline method. Results Based on the samples from costal developed metropolis, the BMI curves successfully overcame the shortcomings of lower and level-off tendency of the Chinese total population. Temporary set H, composed by cut-offs of P85 for overweight and P95 for obesity, was finally selected by its sensitivity and peculiarity. BMI 24 and 28 were used as cut-offs for overweight and obesity for both males and females aged 18 years old. These cut-offs, consistent with Chinese Adult's Reference, was proposed as the Body mass index reference for screening overweight and obesity in Chinese school-age children and adolescents. Conehlsion The new reference clearly showed its superiorty in both prospectivity and actuality. The proposed reference minimized the gaps of the BMI curve between Chinese adolescents and the international reference. Most importantly was that it was consistent with the Eastern Asia ethnic characteristics of body fatness growth. It was therefore proposed by the Working Group on Obesity in China (WGOC) to use it as an nationwide reference for screening overweight and obesity of school-age children and adolescents in China. 展开更多
关键词 Body mass index Chinese school-age children OVERWEIGHT reference
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Baishideng’s Reference Citation Analysis database announces the first Journal Article Influence Index of 101 core journals and a list of high-quality academic journals in gastroenterology and hepatology 被引量:2
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作者 Jin-Lei Wang Yu-Jie Ma +3 位作者 Li Ma Na Ma Diao-Mei Guo Lian-Sheng Ma 《World Journal of Gastroenterology》 SCIE CAS 2022年第37期5383-5394,共12页
After three rounds of rigorous evaluation of core journals in gastroenterology andhepatology conducted by the Reference Citation Analysis (RCA) editorial team ofBaishideng Publishing Group (Baishideng), the RCA databa... After three rounds of rigorous evaluation of core journals in gastroenterology andhepatology conducted by the Reference Citation Analysis (RCA) editorial team ofBaishideng Publishing Group (Baishideng), the RCA database of Baishidengofficially released the 2022 Journal Article Influence Index (2022 JAII) of 101 corejournals in gastroenterology and hepatology, for the first time. The list of 101 corejournals can be found at: https://www.referencecitationanalysis.com/Search-Journal. Among them, the highest 2022 JAII is 48.014 and the lowest is 3.900. Thisarticle highlights the top 20 journals, describes the calculation method for the 2022JAII, the evaluation process, and the inclusion principles for journals in the RCA.These steps are the underpinning of the RCA’s empirical journal academicevaluation service by which the digital platform addresses the needs of authors toselect reliable journals for submission, readers to select high-quality literature forreading, and editors to track their own journal citation performance. As such, theRCA core journal list will serve as a useful Find-a-Journal tool. Any interestedparty is welcome to use this journal list and recommend it to their peers. 展开更多
关键词 reference Citation Analysis Journal Article Influence index Gastroenterology and hepatology Journal list Find a journal Announcement
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Baishideng’s Reference Citation Analysis database announces the first Journal Article Influence Index of 104 core journals and a list of high-quality academic journals in orthopedics 被引量:2
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作者 Jin-Lei Wang Yu-Jie Ma +3 位作者 Li Ma Na Ma Diao-Mei Guo Lian-Sheng Ma 《World Journal of Orthopedics》 2022年第10期891-902,共12页
After three rounds of rigorous evaluation of core journals in orthopedics conducted by the Reference Citation Analysis(RCA)editorial team of Baishideng Publishing Group(Baishideng),the RCA database of Baishideng offic... After three rounds of rigorous evaluation of core journals in orthopedics conducted by the Reference Citation Analysis(RCA)editorial team of Baishideng Publishing Group(Baishideng),the RCA database of Baishideng officially released the 2022 Journal Article Influence Index(2022 JAII)of 104 core journals and a list of high-quality academic journals in orthopedics,for the first time on August 9,2022.The list of 104 core journals can be found at:https://www.referencecitationanalysis.com/SearchJournal.Among them,the highest 2022 JAII is 55.015 and the lowest is 3.076.This article introduces the 21 high-quality academic journals and describes the calculation method for the 2022 JAII,the evaluation process,and the inclusion principles for journals in the RCA.These steps are the underpinning of the RCA’s empirical journal academic evaluation service by which the digital platform addresses the needs of authors to select reliable journals for submission,readers to select high-quality literature for reading,and editors to track their own journal citation performance.As such,the RCA core journal list will serve as a useful Find-a-Journal tool.Any interested party is welcome to use this journal list and recommend it to their peers. 展开更多
关键词 reference Citation Analysis Journal Article Influence index ORTHOPEDICS Journal list Find a journal Announcement
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Baishideng’s Reference Citation Analysis database announces the first Article Influence Index of multidisciplinary scholars 被引量:1
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作者 Jin-Lei Wang Yu-Jie Ma +3 位作者 Li Ma Na Ma Diao-Mei Guo Lian-Sheng Ma 《World Journal of Clinical Cases》 SCIE 2022年第29期10391-10398,共8页
After three rounds of rigorous evaluation of registered scholars conducted by the Reference Citation Analysis(RCA)editorial team of Baishideng Publishing Group(Baishideng),the RCA database of Baishideng officially rel... After three rounds of rigorous evaluation of registered scholars conducted by the Reference Citation Analysis(RCA)editorial team of Baishideng Publishing Group(Baishideng),the RCA database of Baishideng officially released the 2022 Article Influence Index(2022 AII)of 632 scholars from 74 countries/territories in 98 research categories,for the first time.The list of 632 scholars can be found at:https://www.referencecitationanalysis.com/searchscholar.Among them,the highest 2022 AII is 348.211,the highest number of total citations is 42830,and the highest number of total articles is 901.The category with the largest number of RCA scholars is Gastroenterology&Hepatology,with a total of 100(15.8%),and the second is Surgery,with a total of 46(7.3%).This article summarizes the RCA scholars and describes the mission of RCA,the openness and transparency of RCA evaluation,the calculation method for the 2022 AII,and the evaluation process of RCA scholars.The RCA scholar list will effectively serve as a useful Find-a-Scholar tool.Any interested scholar is welcome to register and join this RCA scholar list. 展开更多
关键词 reference Citation Analysis Article Influence index Scholar list Find a scholar Announcement
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Diagnostic Reference Levels of Adults CT-Scan Imaging in Cameroon: A Pilot Study of Four Commonest CT-Protocols in Five Radiology Departments 被引量:1
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作者 Boniface Moifo Jean Roger Moulion Tapouh +3 位作者 Mathurin Neossi Guena Thierry Ndzana Ndah Richard Ndi Samba Augustin Simo 《Open Journal of Medical Imaging》 2017年第1期1-8,共8页
CT-scan is the most irradiating tool in diagnostic radiology. For 5% - 10% of diagnostic X-ray procedures, it is responsible for 34% of irradiation according to UNSCEAR. Patients radiation protection must therefore be... CT-scan is the most irradiating tool in diagnostic radiology. For 5% - 10% of diagnostic X-ray procedures, it is responsible for 34% of irradiation according to UNSCEAR. Patients radiation protection must therefore be increased during CT-scan procedures. This requires the rigorous application of optimization principle which imposes to have “diagnostic reference levels”. Objective: The aim of this study was to determine the diagnostic reference levels (DRLs) of the four most frequent CT-scans examinations of adults in Cameroon. Material and Method: It was a cross-sectional pilot study carried out from April to September 2015 in five health facilities using CT-scan in Cameroon. The studied variables were: patients age and sex, type of CT-scan examination (cerebral, chest, abdomino-pelvic, lumbar spine), Used of IV contrast (IV﹣/ IV+), acquisition length, time of tube rotation, voltage (kV), mAs, pitch, thickness of slices, CTDIvol and DLP. For each type of examination, at least 30 patients were included per center, consecutively on the randomly predetermined days. The DRL for each type of examination was defined as the 75th percentile of its PDL and CTDIvol. Results: Of the 696 examinations, 41.2% were cerebral, 26.9% abdomino-pelvic, 17.7% lumbar spine and 14.2% chest. The mean age of patients was 52 ± 15 years [20 - 90 years], 58.9% were 50 years and older. The sex-ratio was 1.26 (55.9% males). The CT machines were 4, 8 and 16 multidetectors. The 75th percentile of DLP or DRLs [standard deviation] was: [1150 ± 278 mGy·cm], [770 ± 477 mGy·cm], [720 ± 170 mGy·cm] and [715 ± 187 mGy·cm] respectively for cerebral, lumbar spine, abdominopelvic and chest CT-scans. Taking in consideration the number of detectors, the 75th percentile of the Dose-Length product decreased with the increase number of detectors for cerebral examinations but was the highest with 16 MDCT for the abdominopelvic, lumbar spine and chest CT-scans. For the chest and lumbar spine examinations, there was a significant increase in patient-dose with the increase in the number of detectors. Conclusion: Our DRLs values lie between the norms of some European countries and those of some African countries. There is remarquable variation in dose for the commonest CT-scans examinations in Cameroon, requiring then an optimization process from these determined DRLs and establishment of national DRLs. Special attention to optimization should be paid when using 16 MDCT. 展开更多
关键词 Optimization DIAGNOSTIC reference LEVELS DOSE Length Product CT DOSE index Patient DOSE Radiation Protection Best Practices
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Refining the Reference Values of Diers 4D Formetric System and Introducing a Qualitative Spine Profile Based on Percentile Ranking 被引量:1
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作者 Luc Peeters Grégoire Lason +1 位作者 Geert Byttebier Frank Comhaire 《Open Journal of Medical Imaging》 2015年第3期150-158,共9页
Background: In order to detect possible abnormalities of the spine posture of an individual patient, it is mandatory to dispose of adequate reference values based on measurements in a normal, symptom-free population. ... Background: In order to detect possible abnormalities of the spine posture of an individual patient, it is mandatory to dispose of adequate reference values based on measurements in a normal, symptom-free population. The Diers formetric?system allows for non-invasive and accurate assessment of the vertebral column based on the registration of external aspect of the back surface using the Moiré principle. Objective: To create a qualitative spine profile based on the percentile ranking of measurements obtained by the Diers formetric system taking into account possible confounding factors. Materials and Methods: Statistical analysis of formetric recordings in 216 symptom-free volunteers. Results: Maximal kyphotic angle, maximal scoliotic angle, sagittal imbalance, flèche cervicale, and pelvic inclination are significantly influenced by gender and by body mass index (BMI). A synoptic chart was created presenting the percentile ranking taking into account gender and BMI. The percentile ranking was summarized in both a table with colour code and depicted in a histogram of the individual’s Qualitative Spine Profile (QSP). Clinical Significance: Percentile ranking and the Quantitative Spine Profile taking into account gender and BMI should permit a more precise and reliable assessment of possible posture deviations related to the patient’s complaints, and may assist the therapist in selecting the best mode of treatment. 展开更多
关键词 Diers Formetric System SPINE reference Values KYPHOSIS LORDOSIS SAGITTAL IMBALANCE Body Mass index Back Pain OSTEOPATHY Quantitative SPINE Profile
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SR-DCSK Cooperative Communication System with Code Index Modulation:A New Design for 6G New Radios 被引量:1
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作者 Yi Fang Wang Chen +2 位作者 Pingping Chen Yiwei Tao Mohsen Guizani 《China Communications》 SCIE CSCD 2023年第10期1-16,共16页
This paper proposes a high-throughput short reference differential chaos shift keying cooperative communication system with the aid of code index modulation,referred to as CIM-SR-DCSK-CC system.In the proposed CIM-SR-... This paper proposes a high-throughput short reference differential chaos shift keying cooperative communication system with the aid of code index modulation,referred to as CIM-SR-DCSK-CC system.In the proposed CIM-SR-DCSK-CC system,the source transmits information bits to both the relay and destination in the first time slot,while the relay not only forwards the source information bits but also sends new information bits to the destination in the second time slot.To be specific,the relay employs an N-order Walsh code to carry additional log_(2)N information bits,which are superimposed onto the SRDCSK signal carrying the decoded source information bits.Subsequently,the superimposed signal carrying both the source and relay information bits is transmitted to the destination.Moreover,the theoretical bit error rate(BER)expressions of the proposed CIMSR-DCSK-CC system are derived over additive white Gaussian noise(AWGN)and multipath Rayleigh fading channels.Compared with the conventional DCSKCC system and SR-DCSK-CC system,the proposed CIM-SR-DCSK-CC system can significantly improve the throughput without deteriorating any BER performance.As a consequence,the proposed system is very promising for the applications of the 6G-enabled lowpower and high-rate communication. 展开更多
关键词 differential chaos shift keying cooperative communication short reference code index modulation high throughput bit error rate
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Temporal variations of reference evapotranspiration and controlling factors:Implications for climatic drought in karst areas
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作者 Xiao-jiao Guo Wen-zhong Wang +5 位作者 Cheng-xi Li Wei Wang Jian-sheng Shi Ying Miao Xing-bo Hao Dao-xian Yuan 《Journal of Groundwater Science and Engineering》 2022年第3期267-284,共18页
Variations in reference evapotranspiration(ET_(0)) and drought characteristics play a key role in the effect of climate change on water cycle and associated ecohydrological patterns.The accurate estimation of ET_(0) i... Variations in reference evapotranspiration(ET_(0)) and drought characteristics play a key role in the effect of climate change on water cycle and associated ecohydrological patterns.The accurate estimation of ET_(0) is still a challenge due to the lack of meteorological data and the heterogeneity of hydrological system.Although there is an increasing trend in extreme drought events with global climate change,the relationship between ET_(0) and aridity index in karst areas has been poorly studied.In this study,we used the Penman-Monteith method based on a long time series of meteorological data from 1951 to 2015 to calculate ET_(0)in a typical karst area,Guilin,Southwest China.The temporal variations in climate variables,ET_(0)and aridity index(AI)were analyzed with the Mann-Kendall trend test and linear regression to determine the climatic characteristics,associated controlling factors of ET_(0) variations,and further to estimate the relationship between ET_(0) and AI.We found that the mean,maximum and minimum temperatures had increased significantly during the 65-year study period,while sunshine duration,wind speed and relative humidity exhibited significant decreasing trends.The annual ET_(0) showed a significant decreasing trend at the rate of−8.02 mm/10a.However,significant increase in air temperature should have contributed to the enhancement of ET_(0),indicating an“evaporation paradox”.In comparison,AI showed a slightly declining trend of−0.0005/a during 1951-2015.The change in sunshine duration was the major factor causing the decrease in ET_(0),followed by wind speed.AI had a higher correlation with precipitation amount,indicating that the variations of AI was more dependent on precipitation,but not substantially dependent on the ET_(0).Although AI was not directly related to ET_(0),ET_(0)had a major contribution to seasonal AI changes.The seasonal variations of ET_(0)played a critical role in dryness/wetness changes to regulate water and energy supply,which can lead to seasonal droughts or water shortages in karst areas.Overall,these findings provide an important reference for the management of agricultural production and water resources,and have an important implication for drought in karst regions of China. 展开更多
关键词 reference evapotranspiration Aridity index Penman-Monteith method Sunshine duration GUILIN
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Author Index Page number refers to the first page of paper
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《交通运输系统工程与信息》 EI CSCD 2011年第6期216-221,共6页
关键词 JUN PAGE PING LI Author index Page number refers to the first page of paper
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Subject Index Page number refers to the first page of paper
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《交通运输系统工程与信息》 EI CSCD 2011年第6期206-215,共10页
关键词 PAGE Subject index Page number refers to the first page of paper MODE
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Author Index Page number refers tothe first page of paper
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《交通运输系统工程与信息》 EI CSCD 2009年第6期181-186,共6页
关键词 交通运输系统工程 PAGE PING Author index Page number refers tothe first page of paper
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Subject Index Page number refers tothe first page of paper
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《交通运输系统工程与信息》 EI CSCD 2009年第6期173-180,共8页
关键词 PAGE SIMULATION Subject index Page number refers tothe first page of paper 交通运输系统工程
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Journal of Transportation Systems Engineering and Information Technology Author Index Page number refers tothe first page of paper
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《交通运输系统工程与信息》 EI CSCD 2006年第6期182-186,共5页
关键词 PING PAGE Journal of Transportation Systems Engineering and Information Technology Author index Page number refers tothe first page of paper
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Journal of Transportation Systems Engineering and Information Technology Subject Index Page number refers tothe first page of paper
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《交通运输系统工程与信息》 EI CSCD 2006年第6期174-181,共8页
关键词 PAGE Journal of Transportation Systems Engineering and Information Technology Subject index Page number refers tothe first page of paper MODE
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The Interpretation of the Reference of "Now" in Written Messages: An Experimental View
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作者 Yoko Mizuta 《Journal of Philosophy Study》 2017年第8期455-462,共8页
关键词 实验 指称 语言哲学 语用分析 经验数据 卡普兰 话语 时间
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No-Reference Image Quality Assessment Method Based on Visual Parameters
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作者 Yu-Hong Liu Kai-Fu Yang Hong-Mei Yan 《Journal of Electronic Science and Technology》 CAS CSCD 2019年第2期171-184,共14页
Recent studies on no-reference image quality assessment (NR-IQA) methods usually learn to evaluate the image quality by regressing from human subjective scores of the training samples. This study presented an NR-IQA m... Recent studies on no-reference image quality assessment (NR-IQA) methods usually learn to evaluate the image quality by regressing from human subjective scores of the training samples. This study presented an NR-IQA method based on the basic image visual parameters without using human scored image databases in learning. We demonstrated that these features comprised the most basic characteristics for constructing an image and influencing the visual quality of an image. In this paper, the definitions, computational method, and relationships among these visual metrics were described. We subsequently proposed a no-reference assessment function, which was referred to as a visual parameter measurement index (VPMI), based on the integration of these visual metrics to assess image quality. It is established that the maximum of VPMI corresponds to the best quality of the color image. We verified this method using the popular assessment database—image quality assessment database (LIVE), and the results indicated that the proposed method matched better with the subjective assessment of human vision. Compared with other image quality assessment models, it is highly competitive. VPMI has low computational complexity, which makes it promising to implement in real-time image assessment systems. 展开更多
关键词 BANDWIDTH human VISUAL system information entropy LUMINANCE NO-reference image QUALITY assessment (NR-IQA) VISUAL parameter measurement index (VPMI)
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气候变化背景下山西省气象干旱时空演变特征 被引量:1
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作者 姚宁 蒋昆昊 +3 位作者 谢文馨 张东彦 杨晓娟 于强 《农业机械学报》 EI CAS CSCD 北大核心 2024年第1期270-281,共12页
干旱频发对生态资源、农业发展造成了严重影响,为揭示山西省干旱时空演变特征,基于1971—2020年山西省24个气象站点的逐月气象资料,利用改进的Mann-Kendall方法检验各气象因子的年变化趋势,采用FAO56 Penman-Monteith公式计算参考作物... 干旱频发对生态资源、农业发展造成了严重影响,为揭示山西省干旱时空演变特征,基于1971—2020年山西省24个气象站点的逐月气象资料,利用改进的Mann-Kendall方法检验各气象因子的年变化趋势,采用FAO56 Penman-Monteith公式计算参考作物腾发量(ET0),分析单个气象因子变化情况下ET0的变化特征和对气象因子的敏感性,比较各时间尺度(月、季、年尺度)不同干旱指数(降水距平百分率(Pa)、标准化降水指数(SPI)和标准化降水蒸散指数(SPEI))对山西省干旱灾害监测能力。结果表明:ET0与相对湿度呈负相关,气象因子对ET0的敏感性由大到小依次为相对湿度、日最高气温、2 m处风速、日最低气温、日平均气温,ET0呈波动下降趋势。SPEI能够在多时间尺度上有效反映山西省干旱状况,是该地区干旱监测的有效工具。在月、季、年尺度下,比较3个干旱指数,Pa检测效果较差,SPI和SPEI在某些地理区域存在较大差异,整体而言,SPEI在多数地区检测干旱的性能更好;SPEI-1尺度下,各干旱等级发生频率由大到小依次为轻旱(14.8%)、中旱(10.6%)、重旱(5.6%)、特旱(1.9%),3月干旱发生率最高(34%),12月发生率最低(31.8%),吕梁市、晋中市、大同市干旱情况较为严重;SPEI-3尺度下,季节发生干旱频率由大到小依次为秋季(33.5%)、夏季(32.5%)、春季(31.9%)、冬季(31.4%),大同市、长治市特旱发生频率最高,旱情最为严重,忻州市轻旱频率、朔州市中旱频率、吕梁市重旱频率最高;SPEI-12尺度下,轻、中、重、特旱频率分别为14.8%、10.5%、5.4%、2.3%,SPEI-12相较SPEI-1和SPEI-3识别重旱、特旱的站点更多,并基于游程理论得出,山西省南部干旱频次更多,东部干旱历时更长、干旱严重程度更大,干旱峰值主要出现在山西省南北部,由于年均降水呈波动性下降,年均气温整体上升,山西省的气候趋于暖干化,南北部旱情将有所加重,中部地区旱情有所减缓,全域性干旱仍有很大发生可能。 展开更多
关键词 干旱指数 干旱特征 参考作物腾发量 游程理论 山西省
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档案事业类期刊参考文献计量分析——以《档案管理》为对象
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作者 白清礼 贺亚萍 吕仁杰 《档案管理》 北大核心 2024年第2期116-119,共4页
对《档案管理》期刊2013年1月—2022年12月刊载学术论文的参考文献进行计量分析,研究参考文献的类型、引用、分布、新颖性等方面的规律,为档案学研究和期刊发展提供借鉴。选取划定时间范围内的学术论文1 650篇、参考文献总共17 508条,... 对《档案管理》期刊2013年1月—2022年12月刊载学术论文的参考文献进行计量分析,研究参考文献的类型、引用、分布、新颖性等方面的规律,为档案学研究和期刊发展提供借鉴。选取划定时间范围内的学术论文1 650篇、参考文献总共17 508条,对其进行计量统计分析发现期刊和图书是主要参考文献来源,其他文献类型的实际引用频次低,网络文献引用可追溯率低,具有影响力高但有待稳定等特点。档案学研究者和杂志社应科学认知和利用参考文献。 展开更多
关键词 档案学 核心期刊 学术论文 参考文献 引文分析 普莱斯指数 学术价值 网络文献
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环境监测用高锰酸盐指数和氨氮标准溶液量值比对研究
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作者 马莹 杨永 +5 位作者 谭铃 巢静波 樊丽妃 贺岩涛 陈艳 杨婧 《中国环境监测》 CAS CSCD 北大核心 2024年第2期198-204,共7页
针对高锰酸盐指数(COD_(Mn))和氨氮(NH_(3)-N)标准溶液(以下简称液标)制造商、浓度水平和使用情况进行调研,根据调研结果选择常用的7个品牌COD_(Mn)液标和9个常用NH_(3)-N液标品牌开展量值比对和质量评价研究,匿名采购129支液标经盲样... 针对高锰酸盐指数(COD_(Mn))和氨氮(NH_(3)-N)标准溶液(以下简称液标)制造商、浓度水平和使用情况进行调研,根据调研结果选择常用的7个品牌COD_(Mn)液标和9个常用NH_(3)-N液标品牌开展量值比对和质量评价研究,匿名采购129支液标经盲样编码后采用《地表水环境质量标准》(GB 3838—2002)推荐标准进行分析测定,计算和评定测定结果的不确定度,以En法进行量值比对评价。研究表明,NH_(3)-N液标量值均满意,COD_(Mn)测试中的加盖操作会使测定结果偏高,按照证书要求操作时COD_(Mn)液标量值合格,未按照液标证书中要求进行液标样品前处理测定会造成测定结果的偏离,影响评价结果。建议监测人员合理选用和规范使用环境用液标,加强环境用液标的选购和管理,确保检测过程得到有效控制。 展开更多
关键词 环境监测 标准物质/标准样品 高锰酸盐指数 氨氮 质量评价 量值比对
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一种M进制短参考置换索引的差分混沌移位键控系统
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作者 柳粟杰 杨烈君 谢肇鹏 《半导体光电》 CAS 北大核心 2024年第3期485-492,共8页
为解决置换索引的差分混沌移位键控(PI-DCSK)通信系统存在能量效率低的问题,结合短参考技术,提出了一种M进制短参考置换索引的差分混沌移位键控(SR-PI-DCSK)系统。该系统将参考时隙的混沌序列缩短至小于半个符号周期,信息时隙将参考时... 为解决置换索引的差分混沌移位键控(PI-DCSK)通信系统存在能量效率低的问题,结合短参考技术,提出了一种M进制短参考置换索引的差分混沌移位键控(SR-PI-DCSK)系统。该系统将参考时隙的混沌序列缩短至小于半个符号周期,信息时隙将参考时隙的置换排列副本进行复制并拼接P次,在不增加PI-DCSK系统结构复杂度及维持相同的恢复比特信息所需能量的情况下,可以有效提高系统能量效率,同时提升系统的误比特率(BER)。然后,分析了SR-PIDCSK系统的能量效率,推导了其在多径瑞利衰落信道环境下的BER表达式,使用蒙特-卡罗模拟仿真验证了该理论推导的正确性。仿真结果表明,在同一条件下,所提出的系统与PI-DCSK系统相比具有更好的性能增益,这能为下一代物联网短距离通信应用提供一种混沌调制方案。 展开更多
关键词 差分混沌移位键控 短参考置换索引 能量效率
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