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对DPZ08系列直流屏周期计时的探讨
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作者 徐绍杰 《通信电源技术》 1995年第3期46-48,共3页
随着我国电信设备的程控化,国产程控电源迅速地应运而生,并大量投入使用。程控电源设备在供电质量上、自动控制和自动调整性能上,都优越于以往电源设备,很快受到广大用户的信赖。此外,程控电源还具有供电电压范围宽,可以在线连续地为蓄... 随着我国电信设备的程控化,国产程控电源迅速地应运而生,并大量投入使用。程控电源设备在供电质量上、自动控制和自动调整性能上,都优越于以往电源设备,很快受到广大用户的信赖。此外,程控电源还具有供电电压范围宽,可以在线连续地为蓄电池补充能量,确保通信系统的直流不间断供电。 展开更多
关键词 直流屏 周期计 程控电源 通信
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对单摆运动周期计算的讨论
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作者 陆荷琴 葛宇宏 《技术物理教学》 1995年第1期13-14,共2页
对单摆运动周期计算的讨论陆荷琴,葛宇宏(盐城商业学校224001)(盐城建筑工程学校224001)物理教学过程中,常常要涉及计算处于超重、失重状态和处于迭加场中单摆的周期,在特定条件下,这些单摆周期计算的结果,可能式... 对单摆运动周期计算的讨论陆荷琴,葛宇宏(盐城商业学校224001)(盐城建筑工程学校224001)物理教学过程中,常常要涉及计算处于超重、失重状态和处于迭加场中单摆的周期,在特定条件下,这些单摆周期计算的结果,可能式.于是平时勤学好问的学生提出了:根... 展开更多
关键词 单摆运动 摆球 周期计 回复力 简谐振动 洛仑兹力 盐城商业学校 非惯性系统 理想化模型 升降机
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短周期地震计回转摆敏感元件优化设计与仿真 被引量:1
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作者 姚振静 段艳丽 +2 位作者 范业彤 洪利 高强 《科学技术与工程》 北大核心 2018年第31期23-29,共7页
为拓展地震计有效频带范围,对回转摆进行理论分析,得出回转摆频率特性与敏感元件簧片尺寸计算公式。采用ANSYS仿真软件建立回转摆有限元仿真模型,对敏感元件进行模态和静态分析,并对敏感元件簧片尺寸进行优化设计。采用游击力锤激励法... 为拓展地震计有效频带范围,对回转摆进行理论分析,得出回转摆频率特性与敏感元件簧片尺寸计算公式。采用ANSYS仿真软件建立回转摆有限元仿真模型,对敏感元件进行模态和静态分析,并对敏感元件簧片尺寸进行优化设计。采用游击力锤激励法对优化前后的回转摆进行振动模态实验,测试结果表明回转摆模态频率误差在1. 01%以内,验证了优化回转摆仿真模型的合理性。采用正弦标定法测量优化前后地震计的频率特性,实验结果表明:相比于传统敏感元件地震计,优化后回转摆一阶与二阶固有频率差提高了22. 48%,地震计频带范围拓展了21. 42%,为地震计扩展频带范围提供了理论依据。 展开更多
关键词 周期地震 回转摆 敏感元件 固有频率
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短周期与宽频带数字地震计记录波形相关分析 被引量:3
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作者 李霞 张志慧 +1 位作者 周彦文 刘希强 《内陆地震》 2010年第1期50-56,共7页
为了研究短周期与宽频带数字地震观测系统的一致性,分别对山东地震台网青岛、济南、荣成、五莲、烟台的5个同一摆墩上安装的两套观测系统记录的同一地震事件波形资料进行了相关性分析。先将宽频带记录通过等波纹带通滤波器进行频带为1... 为了研究短周期与宽频带数字地震观测系统的一致性,分别对山东地震台网青岛、济南、荣成、五莲、烟台的5个同一摆墩上安装的两套观测系统记录的同一地震事件波形资料进行了相关性分析。先将宽频带记录通过等波纹带通滤波器进行频带为1~20Hz的滤波处理,再将短周期记录进行过采样处理,实现与宽频带记录的采样率一致。分析表明,宽频带和短周期地震计记录近震、地方震和非天然近距离地震波形在形态上一致,地震波形的振幅和相位存在较好相似性,震中距越近地震波形振幅和相位的相似度越高,宽频带和短周期地震计得到速度震级间差别不大,一致性较好。 展开更多
关键词 地震波 周期数字地震 宽频带数字地震 相关性分析
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电容延长周期拾震计与PAM地震遥测仪
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作者 赵仪全 《地震动态与参考》 1989年第5期9-11,共3页
关键词 电容 周期拾震 地震遥测仪
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基于无线射频识别技术的表计信息自动采集系统 被引量:2
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作者 亢宝印 吴丽静 +3 位作者 陈慧芬 曲晓峰 霍艳霞 李宜鹏 《山东电力技术》 2011年第2期68-71,共4页
系统基于无线射频识别技术,利用电子标签作为表计资产的表现和检索形式,通过与自动化库房结合,实现表计出入库信息的动态、批量、自动化采集,减轻工作人员的劳动强度,提高工作效率。同时该技术也将应用于表计的资产管理、库存、配送、... 系统基于无线射频识别技术,利用电子标签作为表计资产的表现和检索形式,通过与自动化库房结合,实现表计出入库信息的动态、批量、自动化采集,减轻工作人员的劳动强度,提高工作效率。同时该技术也将应用于表计的资产管理、库存、配送、装换、稽查、抄收等各个环节,实现表计的全生命周期管理。 展开更多
关键词 无线射频识别(RFID) 电子标签 全生命周期
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New LCA Approach with Fuzzy Evaluation 被引量:5
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作者 张之敬 王信义 曹默 《Journal of Beijing Institute of Technology》 EI CAS 2001年第1期56-62,共7页
A quantitative and comprehensive method of product life cycle assessment(LCA) with fuzzy theory is developed, which will help designers to select the optimum design scheme for product life cycle design(LCD). Based on ... A quantitative and comprehensive method of product life cycle assessment(LCA) with fuzzy theory is developed, which will help designers to select the optimum design scheme for product life cycle design(LCD). Based on the theory of multiple attribute decision making, an algorithm of comprehensive and comparative evaluation for product environmental adaptability is presented. A program is built and used in an example of design improvement. The result shows that the proposed method and algorithm are practical and effective to the development of green products. 展开更多
关键词 life cycle assessment(LCA) fuzzy evaluation environment adaptability life cycle design(LCD) green products
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A Novel Three-parameter Flow Cytometric Analysis for Cell Cycle
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作者 冯永东 陶德定 +5 位作者 覃吉超 高纯 申漫里 冷艳 余源 龚建平 《The Chinese-German Journal of Clinical Oncology》 CAS 2005年第2期76-82,共7页
To set up a three-parameter method for cell cycle analysis by two-laser flowcy-tometer, which can detect two types of cyclin plus DNA content in one measurement, and thatanalyze unscheduled expression of cyclins. Meth... To set up a three-parameter method for cell cycle analysis by two-laser flowcy-tometer, which can detect two types of cyclin plus DNA content in one measurement, and thatanalyze unscheduled expression of cyclins. Methods: Three-color fluorescence was used for analysisof two types of cyclins and DNA content simultaneously in individual cells by two-laser flowcytometry. MOLT-4 cells were used to study the expression of major cyclins in mammalian cells. ATriton-X100 permeabilization procedure was optimized for detection of two types of cyclins. Onecyclin was stained directly with a FITC-conjugated monoclonal antibody (mAb), and the other,indirectly with RPE-Cy5-conjugated secondary antibody, while DNA was stained with the fluorochromeDAPI. mAMSA and mimosine treated MOLT-4 cells were used to test this three-parameter method.Results: Permeabilization with 0.5% Triton-XlOO in PBS containing 1% BSA for 5 min on ice providedoptimal conditions for the simultaneous labelling of two cyclins plus DNA in single cells. It wasfound that the emission spectrum of the three dyes (DAPI, FITC and RPE-Cy5) could be measured withno compensation. Based on cyclinA/cyclinE/DNA flow cytometric analysis, asynchronously growingMOLT-4 cells could be divided into 6 compartments (G1o, G1e, G1l, S, G2, and M) simultaneously,allowing for analysis of cell cycle phase specific perturbations without the necessity of cellsynchronization. Unscheduled cyclin B1 expression was observed in G1 cells treated with mimosine andcyclin E in G2 cells treated with mAMSA. We found that unscheduled cyclin expression paralleledexpected cyclin expression. Conclusion: Thus, three-color FCM analysis of cells may not only beapplied to measure unscheduled vs. expected cyclin expression but may also be used to estimate thefraction of cycling cells in up to 6 cell populations. 展开更多
关键词 cell cycle flow cytometry CYCLIN three-parameter ANALYSIS
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Analysis on the time variation and cycle of observed Argo profile data
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作者 张胜茂 伍玉梅 杨胜龙 《Marine Science Bulletin》 2012年第1期16-27,共12页
The remote sensing data which are used by marine fishery forecast only can get the information of ocean surface, while Argo data can provide fishery forecast with temperature and saltinity data of deeper area. To use ... The remote sensing data which are used by marine fishery forecast only can get the information of ocean surface, while Argo data can provide fishery forecast with temperature and saltinity data of deeper area. To use Argo data in cycle, we need to compute its circle to improve the quality of forecast. In 2001- 2008, the longer circle was 62.7 days and 117.5 days, and the shorter circle was 4.9 days and 9.8 days, which were obtained by power spectrum estimation. And there was an unobvious circle of 7 days. There existed big changes in observed profile data amount between years and within a year. 展开更多
关键词 ARGO CYCLE Power Spectrum Estimate Fourier transform
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Durability zonation standard of concrete structure design 被引量:5
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作者 金伟良 吕清芳 《Journal of Southeast University(English Edition)》 EI CAS 2007年第1期98-104,共7页
Durability zonation standard (DZS) is proposed to provide useful parameters for durable concrete structure design. It deals not only with the influence of environment on structures, but also with types, functions an... Durability zonation standard (DZS) is proposed to provide useful parameters for durable concrete structure design. It deals not only with the influence of environment on structures, but also with types, functions and importance of structures based on the theory of life cycle cost(LCC). First, the basic concept of DZS for concrete structure design is defined. Then the basic principles for DZS are established. The factors for zonation according to natural environmental conditions and structural importance are identified. The usefulness of DZS by citing a real application for concrete highway bridges in Zhejiang Province is demonstrated. Finally, durability regulations are provided accordingly to zonation. 展开更多
关键词 durability zonation standard concrete structure design zonation map life cycle cost
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基于检波器的短周期地震计的改进 被引量:4
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作者 张晓鹏 李世维 +1 位作者 王同东 靳平 《地球物理学进展》 CSCD 北大核心 2014年第5期2466-2471,共6页
基于检波器的Lippmann式短周期地震计利用内部电路提供的高阻尼,拓展检波器的带宽,使其符合流动地震观测的要求.但这种地震计的温度稳定性差且灵敏度低.针对上述缺点,本文根据传感器性能受温度影响的理论模型和前置放大器的设计原理,提... 基于检波器的Lippmann式短周期地震计利用内部电路提供的高阻尼,拓展检波器的带宽,使其符合流动地震观测的要求.但这种地震计的温度稳定性差且灵敏度低.针对上述缺点,本文根据传感器性能受温度影响的理论模型和前置放大器的设计原理,提出了一种改进的方法:使用负温度系数的温度补偿网络和一种新型的前置放大器来改善地震计的性能.改进的基于检波器的短周期地震计的传递性能在很大的温度范围内不受温度的影响,具有较高的灵敏度和较低的噪声水平. 展开更多
关键词 检波器 周期地震 温度稳定性 高灵敏度
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浅谈藏医胚胎学
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作者 万玛才旦 《中国民族医药杂志》 1999年第S1期10-11,共2页
关键词 胎儿发育 胚胎学 藏医学 胚胎发育 人胚胎 《四部医典》 发展史 周期计 发育成长 发育情况
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Grey-theory based algorithm for impact assessment of green design
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作者 李鹏忠 陈炳森 +1 位作者 张为民 黄淑娟 《Journal of Southeast University(English Edition)》 EI CAS 2004年第1期85-89,共5页
Life cycle assessment (LCA) is an important content of green design;the major phase of LCA is impact assessment. After classifying the impact factors, with grey-system theory, the evaluating grey-groups and their whit... Life cycle assessment (LCA) is an important content of green design;the major phase of LCA is impact assessment. After classifying the impact factors, with grey-system theory, the evaluating grey-groups and their whitening weighing functions are defined;the grey-cluster analysis of each classified impact is performed;based on analyzing results, the calculating method of classified impact index is given. By range of action, the impact classes are grouped to three groups - global impact, regional impact, and local impact;the calculating methods of grouped and overall impact index are presented. Finally, an application example of comparative choice of a category of products - three materials, steel, aluminum and engineering plastics is given. 展开更多
关键词 green design impact assessment grey-theory ALGORITHM impact index
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New Exact Travelling Wave Solutions for Generalized Zakharov-Kuzentsov EquationsUsing General Projective Riccati Equation Method 被引量:14
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作者 CHENYong LIBiao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第1期1-6,共6页
Applying the generalized method, which is a direct and unified algebraic method for constructing multipletravelling wave solutions of nonlinear partial differential equations (PDEs), and implementing in a computer alg... Applying the generalized method, which is a direct and unified algebraic method for constructing multipletravelling wave solutions of nonlinear partial differential equations (PDEs), and implementing in a computer algebraicsystem, we consider the generalized Zakharov-Kuzentsov equation with nonlinear terms of any order. As a result, wecan not only successfully recover the previously known travelling wave solutions found by existing various tanh methodsand other sophisticated methods, but also obtain some new formal solutions. The solutions obtained include kink-shapedsolitons, bell-shaped solitons, singular solitons, and periodic solutions. 展开更多
关键词 projective Riccati equation method generalized Zakharov-Kuzentsov equation exact solutions
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Life cycle assessment in the environmental impact evaluation of urbandevelopment--a case study of land readjustment project,Hyogo District, Japan 被引量:5
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作者 葛坚 陆江 HOKAOKazunori 《Journal of Zhejiang University Science》 EI CSCD 2003年第6期702-708,共7页
In this paper, the Life Cycle of Urban Development was firstly analyzed, and the phases of Life Cycle Assessment applied to Urban Development (ULCA) were described. As a case study, ULCA was applied in the environment... In this paper, the Life Cycle of Urban Development was firstly analyzed, and the phases of Life Cycle Assessment applied to Urban Development (ULCA) were described. As a case study, ULCA was applied in the environmental impact assessment of the land readjustment project of Hyogo District of Saga, Japan. In addition, mitigation proposals for reducing CO2 were also presented and the relevant environmental ef-fects were simulated. 展开更多
关键词 Life Cycle Assessment (LCA) Urban development Environmental impact
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A quantitative method for sustainable product development 被引量:1
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作者 Arash Hosseinpour 彭庆金 顾佩华 《Journal of Southeast University(English Edition)》 EI CAS 2015年第1期87-93,共7页
A quantitative measure-based method for the design and evaluation of sustainable products is proposed. The method uses multi-criteria in product design to meet sustainable requirements from qualitative criteria to qua... A quantitative measure-based method for the design and evaluation of sustainable products is proposed. The method uses multi-criteria in product design to meet sustainable requirements from qualitative criteria to quantitative metrics. The method integrates quality function deployment concepts with the life cycle assessment to establish a quantitative method for sustainable product development. It considers both customer needs and sustainable requirements by mapping these needs into design details using the axiomatic design and benchmarking methods. The method is applied in the wheelchair design. Four popular wheelchairs in the market are selected as benchmarks and are rated based on customer needs and sustainable criteria. The design matrix identifies the relationship of functional requirements and design parameters of the wheelchair. Compared to the best benchmark product, the proposed wheelchair can reduce costs by 13.8%, environment footprints 18.55%, mass 4.5%, and components 2.2%. 展开更多
关键词 SUSTAINABILITY product design life cycleassessment BENCHMARKING
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Design of maximizing homogeneous and heterogeneous clustered sensor network lifetime 被引量:1
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作者 金彦亮 蒋轶凡 +1 位作者 陈惠民 刘海涛 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2009年第6期789-798,共10页
Aimed at the problem of unbalanced energy existed in sensor networks, the clustered method is employed to enhance the efficient utilization of limited energy resources of the deployed sensor nodes. In this paper, we d... Aimed at the problem of unbalanced energy existed in sensor networks, the clustered method is employed to enhance the efficient utilization of limited energy resources of the deployed sensor nodes. In this paper, we describe the network lifetime as a function of the communication and data aggregation energy consumption and analyze the lifetime of different transmission schemes in the homogeneous and heterogeneous sensor networks. The analysis carried out in this paper can provide the guidelines for network deployment and protocol design in the future applications. 展开更多
关键词 network lifetime sensor network HOMOGENEOUS HETEROGENEOUS
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The Flexible Housing: Criteria and Strategies for Implementation of the Flexibility 被引量:2
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作者 Cristiana Cellucei Michele Di Sivo 《Journal of Civil Engineering and Architecture》 2015年第7期845-852,共8页
The design of housing systems is today challenged by a highly uncertain context, dominated by the rapid development of functional and technological obsolescence in inherited housing models. If flexibility is the abili... The design of housing systems is today challenged by a highly uncertain context, dominated by the rapid development of functional and technological obsolescence in inherited housing models. If flexibility is the ability of a system to be easily modified and to respond to changes in the environment timely and conveniently, it can be considered as the antidote to obsolescence or the characteristic of the system that guarantees slippage over time. Our paper focuses on the concept of flexibility as a fundamental prerequisite for residential building in order to extend its life cycle design, through strategies and constructive solutions that ensure both the convertibility of the space in response to changing usage and the use of building materials that encourage the reversibility and the long-term easy maintenance of the technological choices that have been implemented. Flexibility is examined both from a conceptual point of view, so as to obtain a clear and logical definition that is distinct from related terms, as well as from a practical point of view, by finding ways to incorporate this requirement into the designing of housing. 展开更多
关键词 RESILIENCE spatial flexibility technological flexibility reversibility.
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Wave Extraction with Portable High-Frequency Surface Wave Radar OSMAR-S 被引量:2
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作者 ZHOU Hao ROARTY Hugh WEN Biyang 《Journal of Ocean University of China》 SCIE CAS 2014年第6期957-963,共7页
High frequency surface wave radar(HFSWR) has now gained more and more attention in real-time monitoring of sea surface states such as current, waves and wind. Normally a small-aperture antenna array is preferred to a ... High frequency surface wave radar(HFSWR) has now gained more and more attention in real-time monitoring of sea surface states such as current, waves and wind. Normally a small-aperture antenna array is preferred to a large-aperture one due to the easiness and low cost to set up. However, the large beam-width and the corresponding incorrect division of the first- and second-order Doppler spectral regions often lead to big errors in wave height and period estimations. Therefore, for the HFSWR with a compact cross-loop/monopole antenna(CMA), a new algorithm involving improved beam-forming(BF) and spectral division techniques is proposed. On one hand, the cross-spectrum of the output sequence by the conventional beam-forming(CBF) with all the three elements and the output with only the two loops is used in place of the CMA output self-spectrum to achieve a decreased beam-width; on the other hand, the better null seeking process is included to improve the division accuracy of the first- and second-order regions. The algorithm is used to reprocess the data collected by the portable HFSWR OSMAR-S during the Sailing Competition of the 16 th Asian Games held in Shanwei in November 2010, and the improvements of both the correlation coefficients and root-mean-square(RMS) errors between the wave height and period estimations and in situ buoy measurements are obvious. The algorithm has greatly enhanced the capabilities of OSMAR-S in wave measurements. 展开更多
关键词 HFSWR wave height wave period in situ comparison beam-forming cross-loop
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Calculate Joint Probability Distribution of Steady Directed Cyclic Graph with Local Data and Domain Casual Knowledge 被引量:1
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作者 Qin Zhang Kun Qiu Zhan Zhang 《China Communications》 SCIE CSCD 2018年第7期146-155,共10页
It is desired to obtain the joint probability distribution(JPD) over a set of random variables with local data, so as to avoid the hard work to collect statistical data in the scale of all variables. A lot of work has... It is desired to obtain the joint probability distribution(JPD) over a set of random variables with local data, so as to avoid the hard work to collect statistical data in the scale of all variables. A lot of work has been done when all variables are in a known directed acyclic graph(DAG). However, steady directed cyclic graphs(DCGs) may be involved when we simply combine modules containing local data together, where a module is composed of a child variable and its parent variables. So far, the physical and statistical meaning of steady DCGs remain unclear and unsolved. This paper illustrates the physical and statistical meaning of steady DCGs, and presents a method to calculate the JPD with local data, given that all variables are in a known single-valued Dynamic Uncertain Causality Graph(S-DUCG), and thus defines a new Bayesian Network with steady DCGs. The so-called single-valued means that only the causes of the true state of a variable are specified, while the false state is the complement of the true state. 展开更多
关键词 directed cyclic graph probabilistic reasoning parameter learning causality complex network
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