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Current Statistics System Fails to Reflect New Changes in International Trade Activities 被引量:2
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作者 万光彩 刘莉 《China Economist》 2007年第3期90-97,共8页
Today developed countries mainly participate in international trade via their foreign affiliates and intermediate goods are more frequently traded as a result of increasingly deepening international divisions of labou... Today developed countries mainly participate in international trade via their foreign affiliates and intermediate goods are more frequently traded as a result of increasingly deepening international divisions of labour.Against this background,the current trade statistical system that is characterized by the statistical principle of cross-border trade and production,and the custom’s registration data collection method,greatly exaggerate the trade imbalance between China and America. Consequently,it is necessary for the Chinese nation to overcome the shortcomings of the current statistical system so as to evaluate more fairly the trade imbalance between China and America by referring to the Ownership-Based Framework of the complimentary statistical system under the US Current Account.This article, on the basis of the statistical principle of oumership,attempts to regulate the distorted trade imbalance resulting from the current trade statistical system,and aims for an increased understanding of the trade imbalance between China and America from a theoretical background,as well as from the points of view of practitioners and decision makers. 展开更多
关键词 statistics system China-US TRADE imbalance Ownership-based statistics TRADE DEFICIT
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Testing Result Statistics-Based Rapid Testing Method for Safety-Critical System 被引量:1
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作者 Zhi-Yao Deng Nan Sang 《Journal of Electronic Science and Technology of China》 2008年第3期338-341,共4页
Safety-critical system (SCS) has highly demand for dependability, which requires plenty of resource to ensure that the system under test (SUT) satisfies the dependability requirement. In this paper, a new SCS rapi... Safety-critical system (SCS) has highly demand for dependability, which requires plenty of resource to ensure that the system under test (SUT) satisfies the dependability requirement. In this paper, a new SCS rapid testing method is proposed to improve SCS adaptive dependability testing. The result of each test execution is saved in calculation memory unit and evaluated as an algorithm model. Then the least quantity of scenario test case for next test execution will be calculated according to the promised SUT's confidence level. The feedback data are generated to weight controller as the guideline for the further testing. Finally, a compre- hensive experiment study demonstrates that this adaptive testing method can really work in practice. This rapid testing method, testing result statistics-based adaptive control, makes the SCS dependability testing much more effective. 展开更多
关键词 ADAPTIVE FEEDBACK safety-critical system statistics TEST
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Photon counting statistics in single multi-level quantum system
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作者 王东升 郑雨军 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第8期307-317,共11页
We theoretically study the statistics of photon emission of single multi-level quantum system by employing the generating functions approach developed recently. The generalized decay constants are included in single m... We theoretically study the statistics of photon emission of single multi-level quantum system by employing the generating functions approach developed recently. The generalized decay constants are included in single multi-level quantum system with quasi-degenerated levels in this work although they are normally neglected in the absence of (quasi-)degeneracies in multi-level quantum system within the rotating wave approximation. The quantum beats, the line shapes and the Mandel's Q parameters, etc. are studied. 展开更多
关键词 photon statistics generating function single quantum system
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Photon counting statistics of V-type three-level systems:The effects of the field fluctuations
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作者 彭勇刚 郑雨军 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第2期152-157,共6页
We investigate the influence of the field fluctuations to the emission photons of V-type three-level systems.The emission intensity I and Mandel's Q parameter show stochastic resonance with respect to the pure dephas... We investigate the influence of the field fluctuations to the emission photons of V-type three-level systems.The emission intensity I and Mandel's Q parameter show stochastic resonance with respect to the pure dephasing constantγp.The amplitude fluctuation of the field causes these systems to lose their coherence.On the other hand,the amplitude fluctuation provides a new interference method for these systems.The quantum beats are shown in the orthogonal system. 展开更多
关键词 photon counting statistics field fluctuation V-type three-level system
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Research on the statistics index system and evaluation method of high and new technology industry development
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作者 李晓东 张霞 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2004年第3期334-337,共4页
During the evolution of the global economic, high and new technology industry has become the main driver to impel the global economy growth via technological advancement, and the main means to guarantee the sustainabl... During the evolution of the global economic, high and new technology industry has become the main driver to impel the global economy growth via technological advancement, and the main means to guarantee the sustainable development of the global economy. In the view of China’s situation, this article analyzes the experiences of OECD in high and new technology industry and gives a statistics index system along with the evaluation method to estimate the development of high and new technology industry. 展开更多
关键词 High and new technology industry DEVELOPMENT statistics index system Evaluation method
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Level Statistics Crossover of Chiral Surface States in a Three-Dimensional Quantum Hall System
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作者 Rubah Kausar Chao Zheng Xin Wan 《Chinese Physics Letters》 SCIE CAS CSCD 2021年第5期99-103,共5页
Recent experiments have demonstrated the realization of the three-dimensional quantum Hall effect in highly anisotropic crystalline materials, such as ZrTe|_5 and BaMnSb_2. Such a system supports chiral surface states... Recent experiments have demonstrated the realization of the three-dimensional quantum Hall effect in highly anisotropic crystalline materials, such as ZrTe|_5 and BaMnSb_2. Such a system supports chiral surface states in the presence of a strong magnetic field, which exhibit a one-dimensional metal-insulator crossover due to suppression of surface diffusion by disorder potential. We study the nontrivial surface states in a lattice model and find a wide crossover of the level-spacing distribution through a semi-Poisson distribution. We also discover a nonmonotonic evolution of the level statistics due to the disorder-induced mixture of surface and bulk states. 展开更多
关键词 Level statistics Crossover of Chiral Surface States in a Three-Dimensional Quantum Hall system QUANTUM
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Differences between lower extremity joint running kinetics captured by marker-based and markerless systems were speed dependent
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作者 Hui Tang Barry Munkasy Li Li 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第4期569-578,共10页
Background:The development of computer vision technology has enabled the use of markerless movement tracking for biomechanical analysis.Recent research has reported the feasibility of markerless systems in motion anal... Background:The development of computer vision technology has enabled the use of markerless movement tracking for biomechanical analysis.Recent research has reported the feasibility of markerless systems in motion analysis but has yet to fully explore their utility for capturing faster movements,such as running.Applied studies using markerless systems in clinical and sports settings are still lacking.Thus,the present study compared running biomechanics estimated by marker-based and markerless systems.Given running speed not only affects sports performance but is also associated with clinical injury prevention,diagnosis,and rehabilitation,we aimed to investigate the effects of speed on the comparison of estimated lower extremity joint moments and powers between markerless and marker-based technologies during treadmill running as a concurrent validating study.Methods:Kinematic data from marker-based/markerless technologies were collected,along with ground reaction force data,from 16 young adults running on an instrumented treadmill at 3 speeds:2.24 m/s,2.91 m/s,and 3.58 m/s(5.0 miles/h,6.5 miles/h,and 8.0 miles/h).Sagittal plane moments and powers of the hip,knee,and ankle were calculated by inverse dynamic methods.Time series analysis and statistical parametric mapping were used to determine system differences.Results:Compared to the marker-based system,the markerless system estimated increased lower extremity joint kinetics with faster speed during the swing phase in most cases.Conclusion:Despite the promising application of markerless technology in clinical settings,systematic markerless overestimation requires focused attention.Based on segment pose estimations,the centers of mass estimated by markerless technologies were farther away from the relevant distal joint centers,which led to greater joint moments and powers estimates by markerless vs.marker-based systems.The differences were amplified by running speed. 展开更多
关键词 BIOMECHANICS Motion capture GAIT Statistical parametric mapping
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Flower morphology of Allium(Amaryllidaceae)and its systematic significance
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作者 Ju Eun Jang Shukherdorj Baasanmunkh +5 位作者 Nudkhuu Nyamgerel Seung-Yoon Oh Jun-Ho Song Ziyoviddin Yusupov Komijlon Tojibaev Hyeok Jae Choi 《Plant Diversity》 SCIE CAS CSCD 2024年第1期3-27,共25页
Allium is a complicated genus that includes approximately 1000 species.Although its morphology is well studied,the taxonomic importance of many morphological traits,including floral traits,are poorly understood.Here,w... Allium is a complicated genus that includes approximately 1000 species.Although its morphology is well studied,the taxonomic importance of many morphological traits,including floral traits,are poorly understood.Here,we examined and measured the floral characteristics of 87 accessions of 74 Allium taxa(belonging to 30 sections and nine subgenera)from Central to Eastern Asian countries.We then examined the taxonomic relationships between select flower characteristics and a phylogenetic tree based on ITS sequences.Our results confirm that floral morphology provides key taxonomic information to assess species delimitation in Allium.We found that perianth color is an important characteristic within the subg.Melanocrommyum,Polyprason,and Reticulatobulbosa.In subg.Allium,Cepa,and Rhizirideum,significant characteristics include ovary shape,perianth shape,and inner tepal apex.For species in subg.Angunium,the key taxonomic character is ovule number(only one ovule in per locule).In the subg.Allium,Cepa,Polyprason,and Reticulatobulbosa,which belong to the third evolutionary line of Allium,hood-like appendages occur in the ovary,although these do not occur in subg.Rhizirideum.Our results also indicated that the flower morphology of several species in some sections are not clearly distinguished,e.g.,sect.Sacculiferum(subg.Cepa)and sect.Tenuissima(subg.Rhizirideum).This study provides detailed photographs and descriptions of floral characteristics and information on general distributions,habitats,and phenology of the studied taxa. 展开更多
关键词 ALLIUM Flower morphology Pistil character Statistical analysis Significant characteristic Species level
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Lottery Numbers and Ordered Statistics
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作者 Kung-Kuen Tse 《Applied Mathematics》 2024年第4期287-291,共5页
The lottery has long captivated the imagination of players worldwide, offering the tantalizing possibility of life-changing wins. While winning the lottery is largely a matter of chance, as lottery drawings are typica... The lottery has long captivated the imagination of players worldwide, offering the tantalizing possibility of life-changing wins. While winning the lottery is largely a matter of chance, as lottery drawings are typically random and unpredictable. Some people use the lottery terminal randomly generates numbers for them, some players choose numbers that hold personal significance to them, such as birthdays, anniversaries, or other important dates, some enthusiasts have turned to statistical analysis as a means to analyze past winning numbers identify patterns or frequencies. In this paper, we use order statistics to estimate the probability of specific order of numbers or number combinations being drawn in future drawings. 展开更多
关键词 LOTTERY Order statistics Hypergeometric Distribution EXPECTATION UNIFORM
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Effect Evaluation of CBL Combined with Rain Classroom Teaching Method in Medical Statistics
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作者 Man Luo Xiaofang Zhang Wei Liu 《Open Journal of Applied Sciences》 2024年第5期1204-1213,共10页
Objective: To explore the application effect of CBL combined with rain classroom teaching method in medical statistics courses. Methods: The undergraduate students of medical imaging technology in 2019 and 2020 in a u... Objective: To explore the application effect of CBL combined with rain classroom teaching method in medical statistics courses. Methods: The undergraduate students of medical imaging technology in 2019 and 2020 in a university were selected as the research objects. A cluster sampling method was used to select 79 undergraduate students from 2019 in the control group and 75 undergraduate students from 2020 in the experimental group. Traditional teaching method and CBL combined with rain classroom teaching method was used in the control group and experimental group respectively. The final examination scores of the two groups were compared. In experimental group, the correlation between the average score in the rain classroom and the final examination score was tested, and the teaching effect was evaluated. Results: The average score of final examination in experimental group and control group was 79.13 ± 10.32 points and 71.54 ± 14.752 points, respectively, which had a statistically significant difference (Z = 2.586, P = 0.012);the final examination scores of the students in the experimental group were positively correlated with the average scores of the rain classroom (r = 0.372, P = 0.001), and the proportion of satisfaction in the experimental group was 94.7%. Conclusion: The CBL combined with rain classroom teaching method can improve the teaching effectiveness of medical statistics courses. 展开更多
关键词 Rain Classroom CBL Medical statistics
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Innovations and Challenges in Economic Census Methodology:A Study by the Bureau of Statistics
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作者 Suqing Li 《Proceedings of Business and Economic Studies》 2024年第5期145-150,共6页
The Bureau of Statistics has demonstrated a forward-looking strategic approach in its economic census.By leveraging dual innovations in technology and management,and incorporating modern technologies such as big data,... The Bureau of Statistics has demonstrated a forward-looking strategic approach in its economic census.By leveraging dual innovations in technology and management,and incorporating modern technologies such as big data,cloud computing,and the Internet of Things,it has deepened the reform of the census methodology.Additionally,the Bureau has built a multi-dimensional collaborative network that enhances international cooperation,departmental coordination,and public participation.This approach not only addresses the limitations of traditional statistical methods in a complex economic environment but also improves data quality and census efficiency,providing an accurate and reliable foundation for national economic decision-making. 展开更多
关键词 Economic census METHODOLOGY Bureau of statistics
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Research on the Application of PBL+SPOC Blended Teaching Model in Probability and Statistics Course
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作者 Hairong Li 《Journal of Contemporary Educational Research》 2024年第9期63-68,共6页
To cultivate talents with an exploratory spirit and practical skills in the era of information technology,it is imperative to reform teaching methods and approaches.In the teaching process of the Probability and Stati... To cultivate talents with an exploratory spirit and practical skills in the era of information technology,it is imperative to reform teaching methods and approaches.In the teaching process of the Probability and Statistics course,an application-oriented blended teaching model combining problem-based learning and small private online course was explored.By organizing and implementing online and offline teaching activities based on problem-based learning,a multidimensional process-oriented learning assessment system was established.Practice has shown that this model can effectively enhance classroom teaching effectiveness,benefiting the improvement of students’overall skills and mathematical literacy. 展开更多
关键词 Problem-based learning teaching method Blended learning Probability and statistics
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Integration of Ideological and Political Education into the Probability Theory and Mathematical Statistics Course:A Teaching Design Based on Estimation and Hypothesis Testing
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作者 Guangyu Li 《Journal of Contemporary Educational Research》 2024年第9期248-254,共7页
With the rapid development of higher education in China,colleges and universities are facing new challenges and impacts in talent training.Probability Theory and Mathematical Statistics is one of the important courses... With the rapid development of higher education in China,colleges and universities are facing new challenges and impacts in talent training.Probability Theory and Mathematical Statistics is one of the important courses in higher education for science and engineering majors and economics and management majors.Its critical role in cultivating students’thinking skills and improving their problem-solving skills is self-evident.Course ideological and political education construction is an important link in college talent training work.Combining ideological and political education with course teaching can help students establish correct value concepts and play a certain role in improving their comprehensive ability and quality.At present,the construction of ideological and political education in the Probability Theory and Mathematical Statistics course still faces some problems,mainly manifested in the lack of attention paid by teachers to course ideological and political education,insufficient exploitation of ideological and political elements,and the simplification of ideological and political education implementation methods.In order to comprehensively deepen the construction of course ideological and political education in line with the actual needs of Probability Theory and Mathematical Statistics course teaching,we should strengthen the construction of teacher teams,improve teachers’ability to carry out course ideological and political education,integrate educational resources,develop educational resources for ideological and political education,and innovate teaching methods to improve the overall effect of ideological and political education integration. 展开更多
关键词 Probability Theory and Mathematical statistics Course education Teaching strategy
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Reservoir parameter inversion based on weighted statistics 被引量:3
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作者 桂金咏 高建虎 +3 位作者 雍学善 李胜军 刘炳杨 赵万金 《Applied Geophysics》 SCIE CSCD 2015年第4期523-532,627,628,共12页
Variation of reservoir physical properties can cause changes in its elastic parameters. However, this is not a simple linear relation. Furthermore, the lack of observations, data overlap, noise interference, and ideal... Variation of reservoir physical properties can cause changes in its elastic parameters. However, this is not a simple linear relation. Furthermore, the lack of observations, data overlap, noise interference, and idealized models increases the uncertainties of the inversion result. Thus, we propose an inversion method that is different from traditional statistical rock physics modeling. First, we use deterministic and stochastic rock physics models considering the uncertainties of elastic parameters obtained by prestack seismic inversion and introduce weighting coefficients to establish a weighted statistical relation between reservoir and elastic parameters. Second, based on the weighted statistical relation, we use Markov chain Monte Carlo simulations to generate the random joint distribution space of reservoir and elastic parameters that serves as a sample solution space of an objective function. Finally, we propose a fast solution criterion to maximize the posterior probability density and obtain reservoir parameters. The method has high efficiency and application potential. 展开更多
关键词 Reservoir parameters INVERSION weighted statistics Bayesian framework stochastic simulation
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Wave statistics for ship seakeeping in China offshore 被引量:1
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作者 刘首华 牟林 +3 位作者 王兴 陈长霖 岳心阳 高志刚 《Marine Science Bulletin》 CAS 2014年第2期1-12,共12页
Ocean waves are the core environmental elements affecting the movements and structure design of ships. Statistical analysis of wave parameters is the basis for the establishment of long-term ship environmental adaptab... Ocean waves are the core environmental elements affecting the movements and structure design of ships. Statistical analysis of wave parameters is the basis for the establishment of long-term ship environmental adaptability prediction model. The observations from coastal stations, buoys, altimeters and volunteer ships that cover from 1993 to 2011 were interpolated into miller Ion-lat grids by using bilinear method and the analytical fields of ocean waves were given. By using optimal interpolation, the analysis wave fields were assimilated into the WAVEWATCH III (WW3) simulation results. From the assimilated results, the wave rose statistics, the wave height of muitiyear return period and the extreme 2-D wave spectrum are related to the ship seakeeping were calculated. Finally, the wave statistics in China offshore were analyzed in detail. 展开更多
关键词 ocean waves statistical characteristics ship seakeeping shipenvironmental adaptability
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Dynamic analysis and experimental study of vibro-acoustic system with uncertainties at middle frequencies 被引量:2
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作者 焦仁强 张建润 薛飞 《Journal of Southeast University(English Edition)》 EI CAS 2017年第2期166-170,共5页
To take into account the influence of uncetainties on the dynamic response of the vibro-acousitc structure, a hybrid modeling technique combining the finite element method(FE)and the statistic energy analysis(SEA)... To take into account the influence of uncetainties on the dynamic response of the vibro-acousitc structure, a hybrid modeling technique combining the finite element method(FE)and the statistic energy analysis(SEA) is proposed to analyze vibro-acoustics responses with uncertainties at middle frequencies. The mid-frequency dynamic response of the framework-plate structure with uncertainties is studied based on the hybrid FE-SEA method and the Monte Carlo(MC)simulation is performed so as to provide a benchmark comparison with the hybrid method. The energy response of the framework-plate structure matches well with the MC simulation results, which validates the effectiveness of the hybrid FE-SEA method considering both the complexity of the vibro-acoustic structure and the uncertainties in mid-frequency vibro-acousitc analysis. Based on the hybrid method, a vibroacoustic model of a construction machinery cab with random properties is established, and the excitations of the model are measured by experiments. The responses of the sound pressure level of the cab and the vibration power spectrum density of the front windscreen are calculated and compared with those of the experiment. At middle frequencies, the results have a good consistency with the tests and the prediction error is less than 3. 5dB. 展开更多
关键词 hybrid finite element method and statistic energy analysis(FE-SEA) method dynamic analysis vibroacoustic system UNCERTAINTIES mid-frequency range
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基于statistics的316L不锈钢柠檬酸钝化工艺正交实验数据分析 被引量:1
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作者 夏明六 韩成树 《热加工工艺》 CSCD 北大核心 2012年第18期42-44,48,共4页
从statistics的数据处理能力出发,运用统计学知识对316L不锈钢柠檬酸钝化工艺参数正交实验数据进行分析,找出钝化速率的主要影响因素;柠檬酸含量5wt%、双氧水含量5wt%、钝化时间60 min为最佳的实验方案;双氧水含量为钝化速率的主要影响... 从statistics的数据处理能力出发,运用统计学知识对316L不锈钢柠檬酸钝化工艺参数正交实验数据进行分析,找出钝化速率的主要影响因素;柠檬酸含量5wt%、双氧水含量5wt%、钝化时间60 min为最佳的实验方案;双氧水含量为钝化速率的主要影响因素。 展开更多
关键词 statistics 316L不锈钢 柠檬酸 数据分析
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Identification of Sewage Monitoring Data Based on Mathematical Statistics
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作者 万玉山 邹涛 +3 位作者 李大伟 温馨 沈梦 陈艳秋 《Agricultural Science & Technology》 CAS 2017年第4期656-659,共4页
In order to reduce the enormous pressure to environmental monitoring work brought by the false sewage monitoring data, Grubbs method, box plot, t test and other methods are used to make depth analysis to the data, pro... In order to reduce the enormous pressure to environmental monitoring work brought by the false sewage monitoring data, Grubbs method, box plot, t test and other methods are used to make depth analysis to the data, providing a set of technological process to identify the sewage monitoring data, which is convenient and simple. 展开更多
关键词 Mathematical statistics Monitoring data Technological process
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A novel method for clustering cellular data to improve classification
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作者 Diek W.Wheeler Giorgio A.Ascoli 《Neural Regeneration Research》 SCIE CAS 2025年第9期2697-2705,共9页
Many fields,such as neuroscience,are experiencing the vast prolife ration of cellular data,underscoring the need fo r organizing and interpreting large datasets.A popular approach partitions data into manageable subse... Many fields,such as neuroscience,are experiencing the vast prolife ration of cellular data,underscoring the need fo r organizing and interpreting large datasets.A popular approach partitions data into manageable subsets via hierarchical clustering,but objective methods to determine the appropriate classification granularity are missing.We recently introduced a technique to systematically identify when to stop subdividing clusters based on the fundamental principle that cells must differ more between than within clusters.Here we present the corresponding protocol to classify cellular datasets by combining datadriven unsupervised hierarchical clustering with statistical testing.These general-purpose functions are applicable to any cellular dataset that can be organized as two-dimensional matrices of numerical values,including molecula r,physiological,and anatomical datasets.We demonstrate the protocol using cellular data from the Janelia MouseLight project to chara cterize morphological aspects of neurons. 展开更多
关键词 cellular data clustering dendrogram data classification Levene's one-tailed statistical test unsupervised hierarchical clustering
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留学生Medical Statistics线上课程建设与远程教学的实践与思考
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作者 丁竞竞 钱炜春 +1 位作者 赵杨 张汝阳 《中国卫生统计》 CSCD 北大核心 2023年第6期942-945,949,共5页
受政治、经济和全球健康等因素影响,远程教育成为高等教育的一个发展趋势。新冠疫情防控期间,受出入境限制,未能返华的留学生一直以远程教学推进学业,成为其间持续进行远程教学最久的群体。本研究总结临床专业本科留学生主干课程Medical... 受政治、经济和全球健康等因素影响,远程教育成为高等教育的一个发展趋势。新冠疫情防控期间,受出入境限制,未能返华的留学生一直以远程教学推进学业,成为其间持续进行远程教学最久的群体。本研究总结临床专业本科留学生主干课程Medical Statistics的校级一流线上课程建设与教学实践,并比较了疫情前后,线下教学与远程教学的留学生期末考试成绩,发现远程教学成绩经历波动后逐渐稳定并接近传统线下教学。本文同时对效果影响因素进行了调研和分析,发现“充分学习和使用远程课程中丰富的资源”和“上网是否容易”是留学生学习效果的主要影响因素。提出建设丰富教学资源对促进医学统计学远程学习效果的重要影响,同时提出对策建议,以期进一步提高远程教学水平,服务高校现代化课程体系建设。 展开更多
关键词 线上课程建设 远程教学实践 Medical statistics 医学统计学 本科留学生
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