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A Successive Shift Box-Counting Method for Calculating Fractal Dimensions and Its Application in Identification of Faults 被引量:1
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作者 沈晓华 邹乐君 +2 位作者 李宏升 沈忠悦 杨树峰 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2002年第2期257-263,共7页
Fractal dimensions of a terrain quantitatively describe the self-organizedstructure of the terrain geometry. However, the local topographic variation cannot be illustrated bythe conventional box-counting method. This ... Fractal dimensions of a terrain quantitatively describe the self-organizedstructure of the terrain geometry. However, the local topographic variation cannot be illustrated bythe conventional box-counting method. This paper proposes a successive shift box-counting method,in which the studied object is divided into small sub-objects that are composed of a series of gridsaccording to its characteristic scaling. The terrain fractal dimensions in the grids are calculatedwith the successive shift box-counting method and the scattered points with values of fractaldimensions are obtained. The present research shows that the planar variation of fractal dimensionsis well consistent with fault traces and geological boundaries. 展开更多
关键词 TERRAIN fractal dimension successive shift box-counting method identification of faults
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Improved Data Processing of Loading Spectrum for Applications of Rainflow Counting Method
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作者 吕志强 彭卫文 黄洪钟 《Journal of Donghua University(English Edition)》 EI CAS 2015年第6期919-922,共4页
The rainflow counting method is a reasonable cyclecounting procedure for fatigue life calculation and simulation testing of structures.It defines cycles as closed stress /strain hysteresis loops.Application of the rai... The rainflow counting method is a reasonable cyclecounting procedure for fatigue life calculation and simulation testing of structures.It defines cycles as closed stress /strain hysteresis loops.Application of the rainflow counting method requires a data processing of the loading spectrum,which consists of the elimination of non-peak value data points,load time histories adjustment and loop extraction.In the data processing of the loading spectrum,if a stress point is neither the peak nor the valley,it will be identified and eliminated from the loading spectrum.Generally,the loading process is idealized as a single peak-valley straight line.But in actually,there are polylines or nearly straight lines between peaks and valleys which can't be ignored.Therefore,in the process of eliminating such data points,it will produce error in method itself.To reduce the error produced by the traditional method itself,a new method which can well simplify the polylines in data processing of loading spectrum is proposed in this paper.Comparing with the original approximation method,the proposed method has higher precision. 展开更多
关键词 fatigue life rainflow counting method loading spectrum LOOP peaks and valleys
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The Study on Taxonomic Status of Trimeresurus stejnegeri chenbihuii Based on Scale Counting Method
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作者 Xiangjun WANG Wen CHEN +3 位作者 Haili TANG Yu DU Chixian LIN Wenjin CHEN 《Agricultural Biotechnology》 CAS 2020年第2期56-59,81,共5页
[Objectives] This study was conducted to further investigate the taxonomic status of Hainan population of Trimeresurus stejnegeri from the morphological point of view.[Methods]The difference coefficients between diffe... [Objectives] This study was conducted to further investigate the taxonomic status of Hainan population of Trimeresurus stejnegeri from the morphological point of view.[Methods]The difference coefficients between different populations were compared using the 75% law,and the relationship between scales and latitudes was analyzed.[Results] The scales(abdominal and subcaudal) of 325 Trimeresurus individuals were counted according to China Animal Fauna,including156 T.stejnegeri individuals.Some difference coefficients between the Hainan population and others were greater than 1.28,and there was no correlation between the number of scales and latitude.It conforms to subclassification criteria.[Conclusions]The view about the subspecies status of T.stejnegeri chenbihuii should be supported. 展开更多
关键词 TRIMERESURUS T.stejnegeri HAINAN SUBSPECIES Population SCALE counting method 75%law LATITUDE
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Research and application of uniform material counting method based on machine vision
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作者 XIAO Suhua QIAO Mingjuan +3 位作者 WANG Zhiyong WANG Wei FU Youzhi GUO Shusen 《Optoelectronics Letters》 EI 2023年第2期123-128,共6页
Manufacturing and agricultural industries use manual methods to count materials. This leads to low accuracy and inefficiency. This paper proposes a secondary counting method that combines main and differential countin... Manufacturing and agricultural industries use manual methods to count materials. This leads to low accuracy and inefficiency. This paper proposes a secondary counting method that combines main and differential counting. The area-fill identification algorithm is applied to mark the counted materials. To verify the effectiveness of the proposed counting algorithm, numbers of countings are conducted for different materials, such as the screws, hole gaskets, beans, jujube, etc. The results show that the counting accuracy reaches 98% for materials with size of 2—20 mm. The method has delivered a high-efficiency and high-accuracy automatic intelligent counting, with a wide range of application prospects and reference value. 展开更多
关键词 uniform material counting method machine vision
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ON THE LATTICE PATH METHOD IN CONVOLUTION-TYPE COMBINATORIAL IDENTITIES(Ⅱ)—THE WEIGHTED COUNTING FUNCTION METHOD ON LATTICE PATHS
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作者 初文吕 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1989年第12期1131-1135,共5页
An independent method for paper [10] is presented. Weighted lattice paths are enumerated by counting function which is a natural extension of Gaussian multinomial coefficient in the case of unrestricted paths. Convolu... An independent method for paper [10] is presented. Weighted lattice paths are enumerated by counting function which is a natural extension of Gaussian multinomial coefficient in the case of unrestricted paths. Convolutions for path counts are investigated, which yields some Vandcrmondc-type identities for multinomial and q-multinomial coefficients. 展开更多
关键词 THE WEIGHTED counting FUNCTION method ON LATTICE PATHS ON THE LATTICE PATH method IN CONVOLUTION-TYPE COMBINATORIAL IDENTITIES
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Fatigue Safety Assessment of Concrete Continuous Rigid Frame Bridge Based on Rain Flow Counting Method and Health Monitoring Data
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作者 Yinghua Li Junyong He +1 位作者 Xiaoqing Zeng Yanxing Tang 《Journal of Architectural Environment & Structural Engineering Research》 2023年第3期31-40,共10页
The fatigue of concrete structures will gradually appear after being subjected to alternating loads for a long time,and the accidents caused by fatigue failure of bridge structures also appear from time to time.Aiming... The fatigue of concrete structures will gradually appear after being subjected to alternating loads for a long time,and the accidents caused by fatigue failure of bridge structures also appear from time to time.Aiming at the problem of degradation of long-span continuous rigid frame bridges due to fatigue and environmental effects,this paper suggests a method to analyze the fatigue degradation mechanism of this type of bridge,which combines long-term in-site monitoring data collected by the health monitoring system(HMS)and fatigue theory.In the paper,the authors mainly carry out the research work in the following aspects:First of all,a long-span continuous rigid frame bridge installed with HMS is used as an example,and a large amount of health monitoring data have been acquired,which can provide efficient information for fatigue in terms of equivalent stress range and cumulative number of stress cycles;next,for calculating the cumulative fatigue damage of the bridge structure,fatigue stress spectrum got by rain flow counting method,S-N curves and damage criteria are used for fatigue damage analysis.Moreover,it was considered a linear accumulation damage through the Palmgren-Miner rule for the counting of stress cycles.The health monitoring data are adopted to obtain fatigue stress data and the rain flow counting method is used to count the amplitude varying fatigue stress.The proposed fatigue reliability approach in the paper can estimate the fatigue damage degree and its evolution law of bridge structures well,and also can help bridge engineers do the assessment of future service duration. 展开更多
关键词 Long-span continuous rigid frame bridge Rain flow counting method Fatigue performance Health monitoring system Strain monitoring data
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A Count Sketch Maximal Weighted Residual Kaczmarz Method with Oblique Projection for Highly Overdetermined Linear Systems 被引量:2
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作者 Peng Zhang Longyan Li Pingping Zhang 《Advances in Pure Mathematics》 2022年第4期260-270,共11页
Motivated by the count sketch maximal weighted residual Kaczmarz (CS-MWRK) method presented by Zhang and Li (Appl. Math. Comput., 410, 126486), we combine the count sketch tech with the maximal weighted residual Kaczm... Motivated by the count sketch maximal weighted residual Kaczmarz (CS-MWRK) method presented by Zhang and Li (Appl. Math. Comput., 410, 126486), we combine the count sketch tech with the maximal weighted residual Kaczmarz Method with Oblique Projection (MWRKO) constructed by Wang, Li, Bao and Liu (arXiv: 2106.13606) to develop a new method for solving highly overdetermined linear systems. The convergence rate of the new method is analyzed. Numerical results demonstrate that our method performs better in computing time compared with the CS-MWRK and MWRKO methods. 展开更多
关键词 count Sketch Oblique Projection Kaczmarz method Linear System
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Sensitivity of diagnosis of spontaneous bacterial peritonitis is higher with the automated cell count method 被引量:1
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作者 Juan G Acevedo-Haro Waddah Mohamed +8 位作者 Prebashan Moodley Oliver Bendall Kris Bennett Nigel Keelty Sally Chan Sam Waddy Joanne Hosking Wayne Thomas Robert Tilley 《World Journal of Hepatology》 2024年第11期1265-1281,共17页
BACKGROUND Spontaneous bacterial peritonitis(SBP)is one of the most important complications of patients with liver cirrhosis entailing high morbidity and mortality.Making an accurate early diagnosis of this infection ... BACKGROUND Spontaneous bacterial peritonitis(SBP)is one of the most important complications of patients with liver cirrhosis entailing high morbidity and mortality.Making an accurate early diagnosis of this infection is key in the outcome of these patients.The current definition of SBP is based on studies performed more than 40 years ago using a manual technique to count the number of polymorphs in ascitic fluid(AF).There is a lack of data comparing the traditional cell count method with a current automated cell counter.Moreover,current international guidelines do not mention the type of cell count method to be employed and around half of the centers still rely on the traditional manual method.AIM To compare the accuracy of polymorph count on AF to diagnose SBP between the traditional manual cell count method and a modern automated cell counter against SBP cases fulfilling gold standard criteria:Positive AF culture and signs/symptoms of peritonitis.METHODS Retrospective analysis including two cohorts:Cross-sectional(cohort 1)and case-control(cohort 2),of patients with decompensated cirrhosis and ascites.Both cell count methods were conducted simultaneously.Positive SBP cases had a pathogenic bacteria isolated on AF and signs/symptoms of peritonitis.RESULTS A total of 137 cases with 5 positive-SBP,and 85 cases with 33 positive-SBP were included in cohort 1 and 2,respectively.Positive-SBP cases had worse liver function in both cohorts.The automated method showed higher sensitivity than the manual cell count:80%vs 52%,P=0.02,in cohort 2.Both methods showed very good specificity(>95%).The best cutoff using the automated cell counter was polymorph≥0.2 cells×10^(9)/L(equivalent to 200 cells/mm^(3))in AF as it has the higher sensitivity keeping a good specificity.CONCLUSION The automated cell count method should be preferred over the manual method to diagnose SBP because of its higher sensitivity.SBP definition,using the automated method,as polymorph cell count≥0.2 cells×10^(9)/L in AF would need to be considered in patients admitted with decompensated cirrhosis. 展开更多
关键词 Spontaneous bacterial peritonitis DIAGNOSIS CIRRHOSIS Bacterial infection Automated cell count method Manual cell count method Ascitic fluid
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Comparative Study on the Correction of Lipemia Interference in Complete Blood Count
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作者 Lirong He 《Journal of Advances in Medicine Science》 2025年第1期1-5,共5页
Background:Lipemia,characterized by elevated triglyceride levels in blood samples,is a prevalent preanalytical interferent in clinical hematology.It leads to erroneous measurements of key complete blood count(CBC)para... Background:Lipemia,characterized by elevated triglyceride levels in blood samples,is a prevalent preanalytical interferent in clinical hematology.It leads to erroneous measurements of key complete blood count(CBC)parameters,including falsely elevated hemoglobin(Hgb)and platelet(PLT)counts.These inaccuracies can compromise diagnostic reliability and patient management.Objective:This review systematically evaluates existing correction methods for lipemic interference in CBC analysis,comparing their efficacy,limitations,and applicability in clinical settings.Methods:We analyze saline replacement,formula-based correction,instrument-specific algorithms,and emerging technologies,supported by experimental and clinical validation data.Conclusion:An optimized,context-dependent strategy is proposed,integrating multiple correction approaches based on lipemia severity.Future research directions,including artificial intelligence(AI)-enhanced corrections and standardized protocols,are discussed to advance hematology testing accuracy. 展开更多
关键词 Lipemic samples Hemoglobin interference Platelet counting Correction methods Hematology analyzers Optimization strategies
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Time-to-Count测量方法的应用研究 被引量:4
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作者 周伟 方方 +2 位作者 李扬红 李琳琳 黄洪全 《铀矿冶》 CAS 2009年第4期209-212,共4页
Time-to-Count方法是一种通过计算时间差来测量辐射强度的方法。通过控制加到探测元件上的高压,首先测量加上高压后到产生第一个脉冲计数之间的计数时间差,再根据计数时间差进一步计算出辐射强度。这种方法可以消除死时间、饱和电流和... Time-to-Count方法是一种通过计算时间差来测量辐射强度的方法。通过控制加到探测元件上的高压,首先测量加上高压后到产生第一个脉冲计数之间的计数时间差,再根据计数时间差进一步计算出辐射强度。这种方法可以消除死时间、饱和电流和高端脉冲重叠等因素的影响,提高探测效率。利用蒙特卡罗方法对Time-to-Count测量方法进行计算机模拟,进一步证明Time-to-Count测量方法的可行性。 展开更多
关键词 Time-to-count方法 计数时间差 辐射检测 蒙特卡罗模拟
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Time-to-Count方法扩展GM计数管量程的实验研究 被引量:9
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作者 龚军军 邵贝贝 +1 位作者 夏文明 陈君军 《原子能科学技术》 EI CAS CSCD 北大核心 2013年第4期674-678,共5页
GM计数管是一种应用广泛的核辐射探测器,但其线性量程范围较窄。本文分析了采用死时间模型和函数拟合修正方法扩展量程存在的不足,介绍了Time-to-Count方法的工作原理,给出了基于该方法的试验装置设计方案,对实现Time-to-Count方法的脉... GM计数管是一种应用广泛的核辐射探测器,但其线性量程范围较窄。本文分析了采用死时间模型和函数拟合修正方法扩展量程存在的不足,介绍了Time-to-Count方法的工作原理,给出了基于该方法的试验装置设计方案,对实现Time-to-Count方法的脉控高压驱动、时间间隔测量等进行了讨论。在国防科技工业电离辐射一级计量站的校准试验数据表明,试验装置采用单支G1220计数管,量程可扩展至5个数量级,全量程范围线性优于10%。 展开更多
关键词 量程扩展 Time-to-count方法 脉控高压驱动 时间间隔测量
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抽水蓄能电站钢蜗壳低周疲劳载荷谱编制方式研究
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作者 胡蕾 简敏 +2 位作者 张启灵 高晓峰 郭永成 《长江科学院院报》 北大核心 2026年第1期136-143,共8页
抽水蓄能电站机组在反复启停和变负荷运行状态下,钢蜗壳结构承受的静水压力会大幅度变化,长期作用下蜗壳可能发生低周疲劳破坏。以某抽水蓄能电站为例,在ABAQUS中完成了钢蜗壳结构的有限元仿真分析,再基于2016年全年水位监测数据编制不... 抽水蓄能电站机组在反复启停和变负荷运行状态下,钢蜗壳结构承受的静水压力会大幅度变化,长期作用下蜗壳可能发生低周疲劳破坏。以某抽水蓄能电站为例,在ABAQUS中完成了钢蜗壳结构的有限元仿真分析,再基于2016年全年水位监测数据编制不同时间长度的原型载荷谱,并在nCode Designlife平台利用雨流计数法对其处理计算,对比了原型载荷谱、处理后的载荷谱及几种极端情况下载荷谱计算得到的疲劳寿命。结果表明:(1)抽水蓄能电站充水保压蜗壳与混凝土间的间隙闭合存在一定的滞后性,与常规电站大直径充水保压蜗壳的间隙闭合规律相似,可能对抗疲劳性能不利。(2)低周疲劳载荷谱可采用雨流计数或常幅值简化编制方式,但对水位消落深度较大的电站,还需要进一步探索可靠的输入方式。(3)在电站运行期内,钢蜗壳无低周疲劳失效风险。研究结果可对钢蜗壳抗疲劳设计载荷的选取提供帮助。 展开更多
关键词 抽水蓄能电站 钢蜗壳结构 低周疲劳 载荷谱 雨流计数法
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口罩过滤效率检测仪检测方法比较研究及分析
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作者 马子嘉 李腾 +3 位作者 孟盈 黄莎 简艳 石曙光 《计量与测试技术》 2026年第1期181-184,共4页
随着口罩需求的大幅度增长,其性能的检测成为重点。其中,颗粒物的过滤效率是检测的核心指标之一,目前在生产质检中的检测仪器主要采用光度计法和粒子计数器法。本文依据相关国家标准和行业标准,分析国内不同技术标准对检测条件的要求,... 随着口罩需求的大幅度增长,其性能的检测成为重点。其中,颗粒物的过滤效率是检测的核心指标之一,目前在生产质检中的检测仪器主要采用光度计法和粒子计数器法。本文依据相关国家标准和行业标准,分析国内不同技术标准对检测条件的要求,并根据扫描电迁移率粒径谱仪中过滤材料上下游气溶胶的粒径谱分布数据,对比两种方法对测定结果的影响,从而优化检测方法,为保障检测质量、更好地服务于医疗和个人防护提供技术支撑。 展开更多
关键词 口罩过滤效率 粒子计数法 光度计法 扫描电迁移率粒径谱仪
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四象限铅栅模体法对SPECT固有空间分辨力和线性影响研究
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作者 洪浩 李静 +1 位作者 王雪鹃 耿建华 《中国医学装备》 2026年第1期28-33,共6页
目的:探索四象限铅栅方位、计数和源距的四象限铅栅模体法对单光子发射计算机断层成像(SPECT)固有空间分辨力和线性影响,为SPECT质量控制与性能检测方法提供参考。方法:依据国家卫生行业标准《伽玛照相机、单光子发射断层成像设备(SPECT... 目的:探索四象限铅栅方位、计数和源距的四象限铅栅模体法对单光子发射计算机断层成像(SPECT)固有空间分辨力和线性影响,为SPECT质量控制与性能检测方法提供参考。方法:依据国家卫生行业标准《伽玛照相机、单光子发射断层成像设备(SPECT)质量控制检测规范》(WS523-2019),将点源放置在距探头铅栅模体表面1.5、1.7、1.9、2.1和2.3 m(1.5~2.3 m),使用四象限铅栅模体法对北京协和医学院肿瘤医院在用的两台SPECT设备双探头所获取的图像固有空间分辨力和线性进行检测,每个点源位置分别采集安装四象限铅栅模体后的计数(60、100、200、300、500、600和1000 k),基于目测判断可分辨的四象限铅栅模体最小象限公式定量计算线源图像的半高宽及目测不同象限线性的畸变程度,检测获取两台SPECT设备双探头的固有空间分辨力和固有空间线性,并分析四象限铅栅不同方位图像可分辨最小象限和线性的一致性。结果:源距固定,当四象限铅栅模体采集计数依次为60 k、100 k、200~300 k、500~1000 k时,获取两台SPECT设备双探头四象限铅栅不同方位图像,四象限铅栅8个方位目测可分辨的最小象限即固有空间分辨力同时依次为4种情况,即四象限铅栅各象限不可分辨、第四象限(6.125 mm)、第三象限(5.25 mm)、第二象限(4.375 mm);固有空间线性均为不可分辨、无线性畸变。四象限铅栅模体检测图像采集计数固定,检测源距1.5~2.3 m时,两台SPECT设备双探头固有空间分辨力和线性检测结果相同。结论:四象限铅栅模体法可完成对SPECT设备固有空间分辨力和线性检测。检测源距在1.5~2.3 m内变化不会对检测结果产生影响。检测时应将每帧图像采集计数≥200 k,铅栅摆放方位优化为正面或反面4个位置。 展开更多
关键词 四象限铅栅法 方位 计数 源距 固有空间分辨力 固有空间线性
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一种快速检测环境中放射性物质的新方法
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作者 沈嘉钰 《粘接》 2026年第2期479-482,共4页
为提高水体中放射性物质的检测灵敏度,建立了一种基于电感耦合等离子体质谱法与液体闪烁计数法的镭-226的快速检测方法。结果表明,该方法镭-226的载体回收率平均为73.15%,检出限为0.02~0.05Bq/L,定量限为0.06~0.15 Bq/L,且回归方程R~2≥... 为提高水体中放射性物质的检测灵敏度,建立了一种基于电感耦合等离子体质谱法与液体闪烁计数法的镭-226的快速检测方法。结果表明,该方法镭-226的载体回收率平均为73.15%,检出限为0.02~0.05Bq/L,定量限为0.06~0.15 Bq/L,且回归方程R~2≥0.999 0,表明该方法具有较高的灵敏度和准确性;精密度均低于5%,平均为2.76%,表明该方法可重复性好;加标回收率为95.28%~98.75%,相对标准偏差为1.92%~3.15%;在实际样品检测中,镭-226的载体回收率为58.43%~84.26%,进一步验证了方法的适用性。本研究为水体中放射性物质的快速监测提供技术支撑,并为相关标准的制定奠定了科学基础。 展开更多
关键词 放射性物质 镭-226 冠醚树脂 电感耦合等离子体质谱法 液体闪烁计数法
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Evaluation of estimation methods for meiofaunal biomass from a meiofaunal survey in Bohai Bay 被引量:4
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作者 张青田 王新华 胡桂坤 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第1期82-87,共6页
Studies in the coastal area of Bohai Bay,China,from July 2006 to October 2007,suggest that the method of meiofaunal biomass estimation affected the meiofaunal analysis.Conventional estimation methods that use a unique... Studies in the coastal area of Bohai Bay,China,from July 2006 to October 2007,suggest that the method of meiofaunal biomass estimation affected the meiofaunal analysis.Conventional estimation methods that use a unique mean individual weight value for nematodes to calculate total biomass may cause deviation of the results.A modified estimation method,named the Subsection Count Method (SCM),was also used to calculate meiofaunal biomass.This entails only a slight increase in workload but generates results of greater accuracy.Results gained using each of these two methods were compared in the present study.The results show that the conventional method generally estimates a meiofaunal biomass.The difference between the two estimation methods was highly significant (P<0.01) for the spring and winter cruises.Furthermore,the estimation method for meiofaunal biomass affected the analysis of horizontal distribution and correlation with environmental factors.These findings highlight the importance of estimation methods for meiofaunal biomass and will hopefully stimulate further investigation and discussion of the topic. 展开更多
关键词 meiofaunal biomass Subsection count method estimation method Bohai Bay China
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基于Count Sketch的预处理贪婪Kaczmarz方法 被引量:1
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作者 叶雨欣 殷俊锋 《同济大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第8期1305-1311,共7页
在贪婪Kaczmarz方法中,通过对系数矩阵进行正交三角分解引入右预处理子能够提高贪婪Kaczmarz方法的收敛速率。但在系数矩阵的行数远大于列数的情况下,正交三角分解的成本过高。为降低预处理的成本,通过引入Count Sketch变换,提出了基于C... 在贪婪Kaczmarz方法中,通过对系数矩阵进行正交三角分解引入右预处理子能够提高贪婪Kaczmarz方法的收敛速率。但在系数矩阵的行数远大于列数的情况下,正交三角分解的成本过高。为降低预处理的成本,通过引入Count Sketch变换,提出了基于Count Sketch的预处理贪婪Kaczmarz方法,并对新方法进行了收敛性分析。理论分析说明了新方法在系数矩阵条件数较大时比已有方法具有更好的收敛速率。数值实验验证了新方法的有效性。 展开更多
关键词 Kaczmarz方法 预处理 count Sketch 收敛性
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Predictive Values of Platelets Count and Spleen Diameter in the Diagnosis of Esophageal Varices in Black African Cirrhotic Patients 被引量:1
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作者 Jean Baptiste Okon Fabrice Ake +2 位作者 Mamadou Diakite Olivier Kouadio Koffi Amadou Kone 《Open Journal of Gastroenterology》 2020年第12期317-328,共12页
<strong>Background:</strong> Gastrointestinal hemorrhage from ruptured esophageal varices is of concern in Africa where gastrointestinal fibroscopy for diagnosis is lacking. <strong>Purpose:</stro... <strong>Background:</strong> Gastrointestinal hemorrhage from ruptured esophageal varices is of concern in Africa where gastrointestinal fibroscopy for diagnosis is lacking. <strong>Purpose:</strong> To determine the performance of the length of the spleen, of the platelet count in the diagnosis of esophageal varices (OVs) by specifying the diagnostic thresholds in order to facilitate the prophylaxis of varicose hemorrhages in black African cirrhotic patients. <strong>Material and Method:</strong> This was a prospective study with a descriptive and analytical aim on cirrhotic patients hospitalized at the university hospital of Bouake (Ivory Coast) from 2017 to 2019. The patients included in the study were the cirrhotic of black race hospitalized having carried out an abdominal ultrasound with measurement of the spleen diameter (SD), an eso-gastro-duodenal endoscopy, and a blood count with platelet count (PC). The first primary endpoint was the diagnosis of esophageal varices in cirrhosis. Cirrhosis was retained by the combination of clinical, biological, ultrasound and endoscopic arguments. The OVs were distributed according to size and the presence of red signs. The platelet count, and the measurement of the spleen to calculate the PC/SD ratio were the second endpoint. The secondary endpoints studied were, the viral and ethyl etiologies of the cirrhosis, the Chlid-Pugh prognostic score. Performance was assessed using the ROC curve. The difference was significant for p less than 0.05. <strong>Results:</strong> The study included 101 patients;they were 79 men (78.2%) and 22 women (21.8%). The mean age of the cirrhotic patients was 48 ± 14. Esophageal varices were present in (n = 93;92%) of cases. The different etiologies were hepatitis B virus (HBV) (n = 65;78.3%), hepatitis C virus (HCV) (n = 21;25, 3%), and alcohol (n = 6;7.2%). Platelet count (PC) < 100,000/mm3 was statistically related to the presence of OV with red signs. Splenomegaly (SD > 130 mm) and PC/SD ratio < 1000 were significantly related to the presence of OVs and large OVs. SD with a cutoff of > 102 mm predicted 75% of OVs (AUROC = 0.797). CP with a cutoff < 131,000/mm3, predicted 100% of OVs (AUROC = 0.756). The PC/SD ratio < 1205 diagnosed 100% of OV (AUROC = 0.801). The PC/SD ratio < 818 and SD > 129 mm predicted large OVs. <strong>Conclusion:</strong> Platelet count, spleen diamater, and PC/SD ratio were all performant for the diagnosis of OVs in our setting with better diagnostic performance for PC/SD. This report could help initiate prophylactic treatment for OVs rupture in cirrhotic patients in health centers where gastrointestinal endoscopy is lacking. 展开更多
关键词 Non-Invasive methods Platelets count Spleen Diameter Esophageal Varices
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Assessment of Three Methods for Estimating Abundance of Ungulate Populations
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作者 陈化鹏 李枫 +4 位作者 王槐 马建章 贾喜波 兰春梅 修可岚 《Journal of Forestry Research》 SCIE CAS CSCD 1997年第2期111-114,共4页
The accuracy of three methods (pellet group count, inverse line transect method and track count) for estimat-ing the density of ungulate population was assessed, based on a wapiti population with the known size in the... The accuracy of three methods (pellet group count, inverse line transect method and track count) for estimat-ing the density of ungulate population was assessed, based on a wapiti population with the known size in the enclosure of500 hm2 on Tonghe Hunting Farm, Heilongjiang province, China, during 1992-1993. The estimation of population densityusing the Pelld group count method was the closeSt to the actual value, whereas the density of the wapiti population wasunderestimated by the inverse line transect method and overestimated by the track count method. No signilicant differenceexisted the estimated and actual values for the pellet group method and the inverse line transed method, but thesignificant differen was found for the track count method. Therefore, it is suggested that the pellet group method should begiven the priority in the survey of ungulate population abundance in practice. 展开更多
关键词 UNGULATE Pellet group count Inverse line transect method Track count
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纤维增强混凝土往复轴压损伤声发射表征 被引量:1
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作者 陈彦恒 肖东 +1 位作者 张旭强 杨晶 《应用声学》 北大核心 2025年第4期877-884,共8页
为探究动态荷载下纤维混凝土疲劳损伤的声发射(AE)响应规律,开展一系列单调轴压和变幅循环轴压试验以及声发射监测,分析不同类型混凝土应力应变全曲线、滞回耗能和损伤演化与声发射特征参数(能量计数和累计AE信号等)的关系,并通过RA-AF... 为探究动态荷载下纤维混凝土疲劳损伤的声发射(AE)响应规律,开展一系列单调轴压和变幅循环轴压试验以及声发射监测,分析不同类型混凝土应力应变全曲线、滞回耗能和损伤演化与声发射特征参数(能量计数和累计AE信号等)的关系,并通过RA-AF分析法判别破坏时不同混凝土裂纹类型及失效模式的区别。结果表明:与素混凝土相比,纤维混凝土滞回环更饱满,耗能能力更强,声发射能量计数更高;纤维的拨出或滑移均可激发AE信号,累计AE信号数随纤维体积掺量的增加或纤维长径比的增大而增多;素混凝土AF值大于RA值更多,且信号稀疏,说明为拉伸裂纹引发的脆性破坏,而纤维混凝土RA值大于AF值更多,且信号增多且密集,说明是由剪切裂纹引发的延性破坏。 展开更多
关键词 纤维增强混凝土 往复轴压 能量计数 累计声发射信号 RA-AF法
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