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Systematic Method for Constructing Lewis Representations
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作者 Lahbib Abbas Lahcen Bih +3 位作者 Khalid Yamni Abderrahim Elyahyaouy Abdelmalik El Attaoui Zahra Ramzi 《Open Journal of Inorganic Chemistry》 2024年第1期1-18,共18页
The systematic method for constructing Lewis representations is a method for representing chemical bonds between atoms in a molecule. It uses symbols to represent the valence electrons of the atoms involved in the bon... The systematic method for constructing Lewis representations is a method for representing chemical bonds between atoms in a molecule. It uses symbols to represent the valence electrons of the atoms involved in the bond. Using a number of rules in a defined order, it is often better suited to complicated cases than the Lewis representation of atoms. This method allows us to determine the formal charge and oxidation number of each atom in the edifice more efficiently than other methods. 展开更多
关键词 systematic method Lewis Representation Chemical Bond Formal Charge Oxidation Number
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Risk Assessment of Diary Cattle Brucellosis Based on Systematic Multilevel Grey Relation Entropy Method
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作者 孙向东 江慎铭 刘拥军 《Agricultural Science & Technology》 CAS 2012年第10期2169-2174,2225,共7页
[Objective] The study was to explore the major factors affecting diary cattle brucellosis risk assessment,as well as their strong-to-weak sequence,so as to provide theoretical basis for assessing diary cattle brucello... [Objective] The study was to explore the major factors affecting diary cattle brucellosis risk assessment,as well as their strong-to-weak sequence,so as to provide theoretical basis for assessing diary cattle brucellosis risk level in different regions.[Method] From 4 dimensions of feeding and importing,breeding,housing and polyculture situation,an evaluation index system was set up,and diary cattle brucellosis risk survey was conducted in 3 typical regions.Finally,systematic multilevel grey relation entropy method was applied to perform data analysis.[Result] The strong-to-weak sequence of Level 1 impact factor of diary cattle brucellosis was as follows:feeding and importinghousingpolyculture situationbreeding;the sequence of Level 2 impact factor was U32〉U12〉U11〉U31〉U21〉U42〉U43〉U23〉U22〉U41;the risk level sequence of 3 typical regions was Province A(County A1,A2,A3)Province B(County B1,B2,B3)Province C(County C1,C2,C3).[Conclusion] According to the weight of Level 1 index strata,administrative departments at all levels and dairy cattle farmers should lay emphasis on the aspects of feeding,importing and housing;viewed from the perspective of Level 2 index strata,dairy cattle farmers should value the siting of cattle field,the brucellosis surveillance before importing and milking modes most.According to the diary cattle brucellosis risk level of 3 typical regions,if administrative departments at all levels strengthen peoples' awareness of their personal health and increase investment in this area,with new healthy cultured atmosphere built,the risk level of diary cattle brucellosis will surly decline. 展开更多
关键词 systematic multilevel grey relation entropy method Diary cattle brucellosis Risk assessment
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SYSTEMATIC METHOD TO GENERATE NEW IDEAS IN FUZZY FRONT END USING TRIZ 被引量:6
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作者 TAN Runhua MA Lihui YANG Bojun SUN Jianguang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2008年第2期114-119,共6页
The obstacle for idea generation in fuzzy front end (FFE) is difficult to apply knowledge in different fields for designers. Theory of inventive problem solving TRIZ and computer-aided innovation systems (CAIs) wh... The obstacle for idea generation in fuzzy front end (FFE) is difficult to apply knowledge in different fields for designers. Theory of inventive problem solving TRIZ and computer-aided innovation systems (CAIs) which are TRIZ-base software systems with a knowledge base provide a framework for knowledge application in different fields. The major methods in TRIZ are selected, which have four types. The problems to be solved for each method are summarized and mapping from the problems to the methods is given. Systematic method with eight paths to integrate the methods and problems is formed. A case study shows the idea generation in FFE using the integrated method step by step. 展开更多
关键词 Idea generation Fuzzy front end (FFE) systematic method TRIZ
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Penalized total least squares method for dealing with systematic errors in partial EIV model and its precision estimation 被引量:3
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作者 Leyang Wang Luyun Xiong Tao Chen 《Geodesy and Geodynamics》 CSCD 2021年第4期249-257,共9页
When the total least squares(TLS)solution is used to solve the parameters in the errors-in-variables(EIV)model,the obtained parameter estimations will be unreliable in the observations containing systematic errors.To ... When the total least squares(TLS)solution is used to solve the parameters in the errors-in-variables(EIV)model,the obtained parameter estimations will be unreliable in the observations containing systematic errors.To solve this problem,we propose to add the nonparametric part(systematic errors)to the partial EIV model,and build the partial EIV model to weaken the influence of systematic errors.Then,having rewritten the model as a nonlinear model,we derive the formula of parameter estimations based on the penalized total least squares criterion.Furthermore,based on the second-order approximation method of precision estimation,we derive the second-order bias and covariance of parameter estimations and calculate the mean square error(MSE).Aiming at the selection of the smoothing factor,we propose to use the U curve method.The experiments show that the proposed method can mitigate the influence of systematic errors to a certain extent compared with the traditional method and get more reliable parameter estimations and its precision information,which validates the feasibility and effectiveness of the proposed method. 展开更多
关键词 Partial EIV model systematic errors Nonlinear model Penalized total least squares criterion U curve method
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Systematic Analysis Method of Shear-Wave Splitting:SAM Software System 被引量:5
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作者 GaoYuan LiuXiqiang +1 位作者 LiangWei HaoPing 《Earthquake Research in China》 2004年第4期365-372,共8页
In order to make a more effective use of the data from regional digital seismograph networks and to promote the study on shear wave splitting and its application to earthquake stress-forecasting, SAM software system, ... In order to make a more effective use of the data from regional digital seismograph networks and to promote the study on shear wave splitting and its application to earthquake stress-forecasting, SAM software system, i.e., the software on systematic analysis method of shear wave splitting has been developed. This paper introduces the design aims, system structure, function and characteristics about the SAM software system and shows some graphical interfaces of data input and result output. Lastly, it discusses preliminarily the study of shear wave splitting and its application to earthquake forecasting. 展开更多
关键词 SAM software system Shear-wave splitting systematic analysis method Earthquake stress-forecasting
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Comparison of the local pivotal method and systematic sampling for national forest inventories
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作者 Minna Räty Mikko Kuronen +3 位作者 Mari Myllymäki Annika Kangas Kai Mäkisara Juha Heikkinen 《Forest Ecosystems》 SCIE CSCD 2020年第4期716-732,共17页
Background:The local pivotal method(LPM)utilizing auxiliary data in sample selection has recently been proposed as a sampling method for national forest inventories(NFIs).Its performance compared to simple random samp... Background:The local pivotal method(LPM)utilizing auxiliary data in sample selection has recently been proposed as a sampling method for national forest inventories(NFIs).Its performance compared to simple random sampling(SRS)and LPM with geographical coordinates has produced promising results in simulation studies.In this simulation study we compared all these sampling methods to systematic sampling.The LPM samples were selected solely using the coordinates(LPMxy)or,in addition to that,auxiliary remote sensing-based forest variables(RS variables).We utilized field measurement data(NFI-field)and Multi-Source NFI(MS-NFI)maps as target data,and independent MS-NFI maps as auxiliary data.The designs were compared using relative efficiency(RE);a ratio of mean squared errors of the reference sampling design against the studied design.Applying a method in NFI also requires a proven estimator for the variance.Therefore,three different variance estimators were evaluated against the empirical variance of replications:1)an estimator corresponding to SRS;2)a Grafström-Schelin estimator repurposed for LPM;and 3)a Matérn estimator applied in the Finnish NFI for systematic sampling design.Results:The LPMxy was nearly comparable with the systematic design for the most target variables.The REs of the LPM designs utilizing auxiliary data compared to the systematic design varied between 0.74–1.18,according to the studied target variable.The SRS estimator for variance was expectedly the most biased and conservative estimator.Similarly,the Grafström-Schelin estimator gave overestimates in the case of LPMxy.When the RS variables were utilized as auxiliary data,the Grafström-Schelin estimates tended to underestimate the empirical variance.In systematic sampling the Matérn and Grafström-Schelin estimators performed for practical purposes equally.Conclusions:LPM optimized for a specific variable tended to be more efficient than systematic sampling,but all of the considered LPM designs were less efficient than the systematic sampling design for some target variables.The Grafström-Schelin estimator could be used as such with LPMxy or instead of the Matérn estimator in systematic sampling.Further studies of the variance estimators are needed if other auxiliary variables are to be used in LPM. 展开更多
关键词 Auxiliary data Bias Local pivotal method Matérn estimator National forest inventory Sampling efficiency Simple random sampling Spatially balanced sampling systematic sampling Variance
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Application of Systematic Clustering Method in the Classification and Changes of Atmospheric Ozone in Hunan Province
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作者 Wenhui YAO Liushu FU +3 位作者 Qian GUO Chunling XU Zhe YANG Wei ZHOU 《Meteorological and Environmental Research》 CAS 2022年第4期1-6,共6页
The cluster analysis method needs continuous improvement and perfection in the research and application of the spatial differentiation and change of pollutants.In this paper,the date of monthly highest concentration o... The cluster analysis method needs continuous improvement and perfection in the research and application of the spatial differentiation and change of pollutants.In this paper,the date of monthly highest concentration of ozone(O_(3))and the concentration value of that day were selected as the similarity coefficient between classes.Single-factor cluster analysis was performed on O_(3)during 2016-2019 and the COVID-19 outbreak of 2020 in Hunan Province using the Ward method.The clustering results showed that the spatial distribution of atmospheric O_(3)in the 14 regions of Hunan Province was most suitable to be classified according to class III clustering areas.That is,the Changsha-Zhuzhou-Xiangtan urban agglomeration was the center,and the high-value area was in northern Hunan.The transition area was in central and southern Hunan,while the low-value area was centered in western Hunan.The partition results were in good agreement with the homogeneous subset of one-way ANOVA and the distribution of monitoring values during the same period.The comparison showed that the inter-class plates in the two periods corresponded well,and the intra-class area showed a continuous geographical distribution,and there were dynamic changes in the spatial differentiation of the O_(3)plates in different periods.In 2020,the center of the O_(3)high-value area plate in Hunan Province moved eastward and extended southward,focusing on the middle and lower reaches of the Xiangjiang River basin,and extending to the upstream area;the regional plate in the transition area expanded significantly;the low-value area plate shrank to the two cities in western Hunan.The abnormal emissions and abnormal climate during the COVID-19 epidemic had an impact on the spatial differentiation of O_(3)in Hunan Province. 展开更多
关键词 OZONE Regional differentiation systematic clustering method
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Systematic Review of Graphical Visual Methods in Honeypot Attack Data Analysis
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作者 Gbenga Ikuomenisan Yasser Morgan 《Journal of Information Security》 2022年第4期210-243,共34页
Mitigating increasing cyberattack incidents may require strategies such as reinforcing organizations’ networks with Honeypots and effectively analyzing attack traffic for detection of zero-day attacks and vulnerabili... Mitigating increasing cyberattack incidents may require strategies such as reinforcing organizations’ networks with Honeypots and effectively analyzing attack traffic for detection of zero-day attacks and vulnerabilities. To effectively detect and mitigate cyberattacks, both computerized and visual analyses are typically required. However, most security analysts are not adequately trained in visualization principles and/or methods, which is required for effective visual perception of useful attack information hidden in attack data. Additionally, Honeypot has proven useful in cyberattack research, but no studies have comprehensively investigated visualization practices in the field. In this paper, we reviewed visualization practices and methods commonly used in the discovery and communication of attack patterns based on Honeypot network traffic data. Using the PRISMA methodology, we identified and screened 218 papers and evaluated only 37 papers having a high impact. Most Honeypot papers conducted summary statistics of Honeypot data based on static data metrics such as IP address, port, and packet size. They visually analyzed Honeypot attack data using simple graphical methods (such as line, bar, and pie charts) that tend to hide useful attack information. Furthermore, only a few papers conducted extended attack analysis, and commonly visualized attack data using scatter and linear plots. Papers rarely included simple yet sophisticated graphical methods, such as box plots and histograms, which allow for critical evaluation of analysis results. While a significant number of automated visualization tools have incorporated visualization standards by default, the construction of effective and expressive graphical methods for easy pattern discovery and explainable insights still requires applied knowledge and skill of visualization principles and tools, and occasionally, an interdisciplinary collaboration with peers. We, therefore, suggest the need, going forward, for non-classical graphical methods for visualizing attack patterns and communicating analysis results. We also recommend training investigators in visualization principles and standards for effective visual perception and presentation. 展开更多
关键词 Honeypot Data Analysis Network Intrusion Detection Visualization and Visual Analysis Graphical methods and Perception systematic Literature Review
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Evaluation of soil nutrient status in poplar forest soil by soil nutrient systematic approach 被引量:5
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作者 余常兵 陈防 +1 位作者 罗治建 陈卫文 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第4期298-300,共3页
A study was conducted to evaluate the soil nutrient status of poplar plantation by Soil Nutrient Systematic Approach (SNSA) in Jianghan Plain, Hubei Province, China. Soil physiochemical properties were analyzed in lab... A study was conducted to evaluate the soil nutrient status of poplar plantation by Soil Nutrient Systematic Approach (SNSA) in Jianghan Plain, Hubei Province, China. Soil physiochemical properties were analyzed in laboratory through collection soil samples of study site. Ten treatments of application different fertilizers were designed such as CK, optimum treatment (N, P, K, Zn), N(P, K, Zn), P(N, K, Zn), K(N, P, Zn), +Mg(N, P, K, Zn, Mg), Zn (N,P,K), +2P(N, 2P, K, Zn), +2K(N, P, 2K, Zn), and 2N+2P+2K(2N, 2P, 2K, Zn) for field experiment to test the effect on tree height, diameter (DBH) growth, and dry weight of poplar. The results showed that there was no significant difference in tree heights between treatments with different fertilizers, diameter growth of poplar trees in treatments of lack of N and Zn was significantly slower than that of trees in optimum treatment, and dry weight of poplar dropped significantly for treatment of CK as well as treatments without application N and Zn. It is concluded that N and Zn were main limiting factor for poplar growth. Results from laboratory analysis and field experiment were uniform per-fectly, which proved that SNSA was reliable in evaluating soil nutrient status of poplar plantation. 展开更多
关键词 Soil nutrient status Soil Nutrient systematic Approach Poplar plantation Limiting factor Evaluation method Soil physiochemical properties
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Endoscopic ultrasound-guided vs endoscopic retrograde cholangiopancreatography biliary drainage for obstructed distal malignant biliary strictures: A systematic review and meta-analysis 被引量:6
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作者 Fernanda P Logiudice Wanderlei M Bernardo +9 位作者 Facundo Galetti Vitor M Sagae Carolina O Matsubayashi Antonio C Madruga Neto Vitor O Brunaldi Diogo T H de Moura Tomazo Franzini Spencer Cheng Sergio E Matuguma Eduardo G H de Moura 《World Journal of Gastrointestinal Endoscopy》 CAS 2019年第4期281-291,共11页
BACKGROUND For palliation of malignant biliary obstruction(MBO), the gold-standard method of biliary drainage is endoscopic retrograde cholangiopancreatography(ERCP)with the placement of metallic stents. Endoscopic ul... BACKGROUND For palliation of malignant biliary obstruction(MBO), the gold-standard method of biliary drainage is endoscopic retrograde cholangiopancreatography(ERCP)with the placement of metallic stents. Endoscopic ultrasound(EUS)-guided drainage is an alternative that is typically reserved for cases of ERCP failure.Recently, however, there have been robust randomized clinical trials(RCTs)comparing EUS-guided drainage and ERCP as primary approaches to MBO.AIM To compare EUS guidance and ERCP in terms of their effectiveness and safety in palliative biliary drainage for MBO.METHODS This was a systematic review and meta-analysis, in which we searched the MEDLINE, Excerpta Medica, and Cochrane Central Register of Controlled Trials databases. Only RCTs comparing EUS and ERCP for primary drainage of MBO were eligible. All of the studies selected provided data regarding the rates of technical and clinical success, as well as the duration of the procedure, adverse events, and stent patency. We assessed the risk of biases using the Jadad score and the quality of evidence using the Grading of Recommendations Assessment,Development and Evaluation criteria.RESULTS The database searches yielded 5920 records, from which we selected 3 RCTs involving a total of 222 patients(112 submitted to EUS and 110 submitted to ERCP). In the EUS and ERCP groups, the rate of technical success was 91.96%n and 91.81%, respectively, with a risk difference(RD) of 0.00%(95%CI:-0.07, 0.07;P = 0.97; I^2 = 0%). The clinical success was 84.81% and 85.53% in the EUS and ERCP groups, respectively, with an RD of-0.01%(95%CI:-0.12, 0.10; P = 0.90; I^2 =0%). The mean difference(MD) for the duration of the procedure was-0.12%(95%CI:-8.20, 7.97; P = 0.98; I^2 = 84%). In the EUS and ERCP groups, there were14 and 25 adverse events, respectively, with an RD of-0.06%(95%CI:-0.23, 0.12; P= 0.54; I^2 = 77%). The MD for stent patency was 9.32%(95%CI:-4.53, 23.18; P =0.19; I^2 = 44%). The stent dysfunction rate was significantly lower in the EUS t group(MD =-0.22%; 95 CI:-0.35,-0.08; P = 0.001; I^2 = 0%).CONCLUSION EUS represents an interesting alternative to ERCP for MBO drainage,demonstrating lower stent dysfunction rates compared with ERCP. Technical and clinical success, duration, adverse events and patency rates were similar. 展开更多
关键词 Common bile duct neoplasms ENDOSCOPIC retrograde CHOLANGIOPANCREATOGRAPHY ENDOSONOGRAPHY Ultrasonography Interventional/methods ENDOSCOPIC ultrasound systematic review META-ANALYSIS
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Systematic Synthesis of Compressive VDTA-Based T-T Filter with Orthogonal Control of f_o and Q 被引量:3
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作者 Yong-An Li Yan-Hua Xi Zhan-Ting Fan 《Journal of Electronic Science and Technology》 CAS CSCD 2020年第3期276-286,共11页
Based on sixteen nullor-mirror models of the voltage differencing transconductance amplifier (VDTA) and port admittance matrices of the tow-Thomas (T-T) filter with orthogonal control between the characteristic freque... Based on sixteen nullor-mirror models of the voltage differencing transconductance amplifier (VDTA) and port admittance matrices of the tow-Thomas (T-T) filter with orthogonal control between the characteristic frequency(f_0) and figure of merit (Q),two different categories of the voltage-mode and transconductance-mode T-T filters are synthesized by the means of the nodal admittance matrix (NAM) expansion method.The category A filter that employs two compressive VDTAs and two grounded capacitors includes four structures,and the category B filter that uses two compressive VDTAs,two grounded capacitors,and one grounded resistor,also includes four structures.These circuits are suitable for integrated circuit manufacture,and their parameters f_0 and Q can be orthogonally adjusted with varying the bias currents of VDTAs.After the paper and pencil test is completed,the computer analyses,including alternating current (AC),parameter sweep,Monte Carlo (MC),and noise analyses,are performed to support the synthesis approach. 展开更多
关键词 Compressive voltage differencing transconductance amplifier(compressive VDTA) nodal admittance matrix(NAM)expansion method systematic synthesis tow-Thomas(T-T)filter
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Duplicates in systematic reviews: A critical, but often neglected issue
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作者 Xing-Shun Qi Ming Bai +1 位作者 Zhi-Ping Yang Wei-Rong Ren 《World Journal of Meta-Analysis》 2013年第3期97-101,共5页
The number of systematic reviews is gradually increas-ing over time. Also, the methods to perform a systematic review are being improved. However, little attention has been paid for the issue regarding how to fnd dupl... The number of systematic reviews is gradually increas-ing over time. Also, the methods to perform a systematic review are being improved. However, little attention has been paid for the issue regarding how to fnd duplicates in systematic reviews. On the basis of the survey and systematic reviews by our team and others, we review the prevalence, significance and classification of duplicates and the method to fnd duplicates in a systematic review. Notably, although a preliminary method to fnd duplicates is established, its usefulness and convenience need to be further confrmed. 展开更多
关键词 Duplicates systematic review method PREVALENCE Signifcance
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Techniques for Determining the Treatment Costs of Cervical Cancer: A Systematic Review
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作者 Candice Amorim de Araújo Lima Santos Ariani Impieri Souza Suely Arruda Vidal 《Open Journal of Obstetrics and Gynecology》 2019年第2期117-128,共12页
Background: Uterine cervical cancer (UCC) represents a public health problem in many part of the world. The use of new technologies is leading to increased treatment costs, resulting in a substantial economic impact w... Background: Uterine cervical cancer (UCC) represents a public health problem in many part of the world. The use of new technologies is leading to increased treatment costs, resulting in a substantial economic impact worldwide. Standardization of economic evaluation methods is needed to improve comparisons between jurisdictions. Objective: To identify the methods used to measure the cost of treating invasive UCC, and to search for correlations between cancer treatment expenditures and local economies. Methods: We searched articles in MEDLINE, LILACS, and SciELO with no language restrictions, and included publications from January 01, 2007 to December 31, 2016. Studies were included if they described the annual direct cost of invasive cervical cancer and detailed the costing method. Complete economic evaluations were excluded. Results were described in 2016 international dollars. Results: Of 1581 studies initially reviewed, 13 articles were included in the analysis. Six articles used a bottom-up;six used a top-down approach and one used both. Annual cost per patient varied from I$ 2146.22 (Poland) to 34,351.54 (Sweden). Middle-income countries (MIC) spent median 72.52% of its GDP per capita on the treatment of invasive cervical cancer, while high-income countries (HIC) spent median 30.12% (p = 0.032). No significant difference was found when separated by costing method. Conclusions: We found that, for the treatment costs of invasive UCC, the percentages of GDP per capita were statistically higher in MIC than in HIC. However, no significant difference was found between costing methods, and the top-down approach could be used. 展开更多
关键词 CERVICAL CANCER COSTS and COST Analysis Costing method systematic Review
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铸牢中华民族共同体意识研究的当代呈现与传播 被引量:1
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作者 王宇 《阴山学刊》 2024年第1期22-26,105,共6页
纵观铸牢中华民族共同体意识研究,主要是通过书籍、报纸、期刊、电视、广播和网站展开宏观辨识,通过纸媒、学术会议、数据库网站传播进行中观探析,通过新媒体传播、现场传播开展微观运作。其传播内容随着认识论、实践论、关系论、价值... 纵观铸牢中华民族共同体意识研究,主要是通过书籍、报纸、期刊、电视、广播和网站展开宏观辨识,通过纸媒、学术会议、数据库网站传播进行中观探析,通过新媒体传播、现场传播开展微观运作。其传播内容随着认识论、实践论、关系论、价值论等多维论域的研究而呈现出丰富广泛的特点。多种研究方法的运用与相互结合,使铸牢中华民族共同体意识研究的传播效果不断积累、深化和扩大。循着最初由内涵阐释到方法路径的摸索、从对历史渊源的体现挖掘到在当代民族工作中的实际运用、由对中国各民族人民铸牢中华民族共同体意识的现实探析到对新生代海外侨胞铸牢中华民族共同体意识的现状分析的研究轨迹,相应地其传播规律划分为接触与显现阶段、选择阶段、融合阶段。因目前铸牢中华民族共同体意识研究呈现出碎片化、重点不突出的问题,且在传播影响力方面有待增强,时下与未来一段时间需要在呈现的体系化与特色化、呈现的方向性与重点性、传播的中国化与国际化几个方面进行进一步深化挖掘与完善。 展开更多
关键词 铸牢中华民族共同体意识 研究论域 研究方法 媒介 传播效果 体系化 重点性
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基于系统聚类法的含新能源电力系统分区策略
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作者 韩平平 郭佳林 +1 位作者 董玮 王正风 《电力系统及其自动化学报》 CSCD 北大核心 2024年第5期114-120,共7页
为实现含新能源电力系统的惯量分布特性的有效评估,提出一种基于系统聚类法的含新能源电力系统分区策略。首先分析新能源机组惯量与同步机组惯量之间的差异;其次构建节点惯量响应模型,分析节点惯量相关因素的特性;然后通过主成分分析对... 为实现含新能源电力系统的惯量分布特性的有效评估,提出一种基于系统聚类法的含新能源电力系统分区策略。首先分析新能源机组惯量与同步机组惯量之间的差异;其次构建节点惯量响应模型,分析节点惯量相关因素的特性;然后通过主成分分析对影响节点惯量的主导变量进行降维,将降维后的变量应用系统聚类法对节点进行聚类分区;最后通过系统辨识得到区域惯量,评判出整个系统惯量的空间分布。在仿真软件中搭建改进的IEEE 10机39节点模型验证了分区策略的合理性。 展开更多
关键词 系统聚类法 新能源电力系统 惯量分区 系统辨识
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基于FTIR的黄芪药材质量评价研究
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作者 郝彩琴 周莹 +1 位作者 刘明嘉 孙国祥 《中南药学》 CAS 2024年第5期1329-1333,共5页
目的 建立黄芪药材的红外原始指纹图谱与量子指纹图谱,为其质量控制提供参考。方法 采用傅里叶变换红外光谱仪采集35批黄芪药材的红外指纹图谱,经数据处理建立黄芪的红外量子指纹图谱,采用系统指纹定量法以及t检验比较两种指纹图谱是否... 目的 建立黄芪药材的红外原始指纹图谱与量子指纹图谱,为其质量控制提供参考。方法 采用傅里叶变换红外光谱仪采集35批黄芪药材的红外指纹图谱,经数据处理建立黄芪的红外量子指纹图谱,采用系统指纹定量法以及t检验比较两种指纹图谱是否存在差异,并对量子指纹图谱的共有量子峰面积进行系统聚类分析。结果 黄芪药材的红外指纹图谱与量子指纹图谱间并不存在显著性差异,系统指纹定量法将35批黄芪分为8个质量等级,系统聚类分析表明35批黄芪的质量可聚为两类。结论 红外量子指纹图谱能够提供大量特征信息,系统指纹定量法能够全面、准确、直观地将黄芪药材分为8个质量等级,两者结合可以实现对黄芪等中药材质量的全面评价。 展开更多
关键词 黄芪 傅里叶变换红外光谱 量子指纹图谱 系统指纹定量法
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大鼠急性血瘀证模型造模方法的网状Meta分析
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作者 宋慧平 岳傲春 +2 位作者 李泽坤 韩伟 李琴 《世界中医药》 CAS 北大核心 2024年第8期1099-1107,共9页
目的:采用网状Meta分析评价不同急性血瘀证模型造模方法的效果,为中医实验研究急性血瘀证动物模型的制备提供循证依据。方法:检索中国期刊全文数据库(CNKI)、中国学术期刊数据库(CSPD)、中文科技期刊数据库(CCD)中有关急性血瘀证模型的... 目的:采用网状Meta分析评价不同急性血瘀证模型造模方法的效果,为中医实验研究急性血瘀证动物模型的制备提供循证依据。方法:检索中国期刊全文数据库(CNKI)、中国学术期刊数据库(CSPD)、中文科技期刊数据库(CCD)中有关急性血瘀证模型的建模方法,应用Stata软件进行网状Meta分析。结果:最终纳入32项研究,共纳入9种造模方案。各项指标最优前3位概率排序分别为:1)全血黏度:1 S^(-)1切变率右旋糖酐>高脂>氢化可的松+肾上腺素,10 S^(-)1切变率冰水浴>肾上腺素>高脂+力竭游泳,30 S^(-)1切变率多因素刺激>右旋糖酐>肾上腺素,60 S^(-)1切变率多因素刺激>右旋糖酐>肾上腺素,150 S^(-)1切变率肾上腺素>冰水浴>高脂+力竭游泳,200 S^(-)1切变率右旋糖酐>氢化可的松+肾上腺素>角叉莱胶+内毒素;2)血浆黏度:右旋糖酐>多因素刺激>肾上腺素;3)红细胞聚集指数:冰水浴>多因素刺激>高脂+力竭游泳。受纳入研究质量和数量的限制,所得结论仍待进一步验证。结论:右旋糖酐、冰水浴、多因素刺激、肾上腺素造模效果更显著。 展开更多
关键词 急性血瘀证 动物模型 造模方法 大鼠 模型评价 实验方法 网状Meta分析 系统评价
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伏安法测电阻的待测电阻选择方法
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作者 何述平 杨英恺 《物理通报》 CAS 2024年第8期95-98,共4页
研究了伏安法测电阻的基于中学物理实验标配电表参量选择待测电阻的方法,结果表明:既要依据相对系统误差,又要依据匹配条件,综合选择待测电阻;给出了方法运用的实例,深化了伏安法测电阻的认识,奠定了精准设计实验教学的基础.
关键词 伏安法 待测电阻 选择方法 相对系统误差 匹配条件
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连续波核磁共振实验中外扫描测量法的改进
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作者 黄水平 钱小青 《大学物理》 2024年第6期16-18,35,共4页
本文对连续波核磁共振实验中外扫描法测横向弛豫时间误差的主要来源进行了分析,对系统误差的大小进行了定量估算.在此基础上,对外扫描法中横向弛豫时间的测量提出了相应的改进措施,通过计算确定了共振信号半高宽测量时共振信号应在的位... 本文对连续波核磁共振实验中外扫描法测横向弛豫时间误差的主要来源进行了分析,对系统误差的大小进行了定量估算.在此基础上,对外扫描法中横向弛豫时间的测量提出了相应的改进措施,通过计算确定了共振信号半高宽测量时共振信号应在的位置.结果表明,外扫描法测量中,通过x方向的相位调节把共振信号移到偏离中心适当距离的位置上来测量其半高宽,可有效降低非线性扫描电压引起的系统误差.此外,通过对误差大小及共振信号测量位置的计算,能加深学生对横向弛豫时间及外扫描测量法原理的理解. 展开更多
关键词 核磁共振 外扫描法 横向弛豫时间 系统误差
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补肾益髓法治疗阿尔茨海默病临床疗效的荟萃分析
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作者 方德宇 张彬彬 +1 位作者 张林 吴品昌 《实用中医内科杂志》 2024年第4期4-8,I0002-I0005,共9页
目的系统评价补肾益髓中药复方治疗阿尔茨海默病的疗效。方法检索6个国内外常用数据库,检索时间为自建库起至2022年7月5日,收集补肾益髓中药复方治疗阿尔茨海默病的临床随机对照试验文献,进行Meta分析。结果共纳入文献研究12篇,共计733... 目的系统评价补肾益髓中药复方治疗阿尔茨海默病的疗效。方法检索6个国内外常用数据库,检索时间为自建库起至2022年7月5日,收集补肾益髓中药复方治疗阿尔茨海默病的临床随机对照试验文献,进行Meta分析。结果共纳入文献研究12篇,共计733例患者,其中试验组371例,对照组362例。分析结果显示应用补肾益髓中药复方治疗阿尔茨海默病在临床治疗有效率[RR=1.63,95%CI(1.37,1.93),Ρ<0.00001],提高患者MMSE评分[MD=1.19,95%CI(0.98,1.40),Ρ<0.00001],降低患者ADAS-cog评分[MD=-2.68,95%CI(-4.95,-0.40),Ρ=0.02],降低患者中医证候评分[SMD=-0.64,95%CI(-0.92,-0.36),Ρ<0.00001]方面优于单纯的常规西医治疗;在降低患者ADL评分上与西医比较差异无统计学意义[MD=-0.78,95%CI(-2.24,-0.40),Ρ=0.69],具有相同疗效;在安全性指标及不良反应方面未见明显异常。结论补肾益髓中药复方治疗阿尔茨海默病对比单纯西医治疗在临床治疗有效率,提高MMSE评分、降低ADAS-Cog和中医证候积分上具有一定优势,但因纳入文献多数质量不高,故仍需开展大规模、多中心、高质量临床试验以进一步验证结论。 展开更多
关键词 中医药 补肾益髓法 阿尔茨海默病 META分析 系统评价
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