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Decentralized Optimal Control and Stabilization of Interconnected Systems With Asymmetric Information
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作者 Na Wang Xiao Liang +1 位作者 Hongdan Li Xiao Lu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第3期698-707,共10页
The paper addresses the decentralized optimal control and stabilization problems for interconnected systems subject to asymmetric information.Compared with previous work,a closed-loop optimal solution to the control p... The paper addresses the decentralized optimal control and stabilization problems for interconnected systems subject to asymmetric information.Compared with previous work,a closed-loop optimal solution to the control problem and sufficient and necessary conditions for the stabilization problem of the interconnected systems are given for the first time.The main challenge lies in three aspects:Firstly,the asymmetric information results in coupling between control and estimation and failure of the separation principle.Secondly,two extra unknown variables are generated by asymmetric information(different information filtration)when solving forward-backward stochastic difference equations.Thirdly,the existence of additive noise makes the study of mean-square boundedness an obstacle.The adopted technique is proving and assuming the linear form of controllers and establishing the equivalence between the two systems with and without additive noise.A dual-motor parallel drive system is presented to demonstrate the validity of the proposed algorithm. 展开更多
关键词 Asymmetric information decentralized control forwardbackward stochastic difference equations interconnected system stalibization
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Establishing minimum clinically important difference values for the Patient-Reported Outcomes Measurement Information System Physical Function, hip disability and osteoarthritis outcome score for joint reconstruction, and knee injury and osteoarthritis out 被引量:3
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作者 Man Hung Jerry Bounsanga +1 位作者 Maren W Voss Charles L Saltzman 《World Journal of Orthopedics》 2018年第3期41-49,共9页
AIM To establish minimum clinically important difference(MCID) for measurements in an orthopaedic patient population with joint disorders.METHODS Adult patients aged 18 years and older seeking care for joint condition... AIM To establish minimum clinically important difference(MCID) for measurements in an orthopaedic patient population with joint disorders.METHODS Adult patients aged 18 years and older seeking care for joint conditions at an orthopaedic clinic took the Patient-Reported Outcomes Measurement Information System Physical Function(PROMIS~? PF) computerized adaptive test(CAT), hip disability and osteoarthritis outcome score for joint reconstruction(HOOS JR), and the knee injury and osteoarthritis outcome score for joint reconstruction(KOOS JR) from February 2014 to April 2017. MCIDs were calculated using anchorbased and distribution-based methods. Patient reports of meaningful change in function since their first clinic encounter were used as an anchor.RESULTS There were 2226 patients who participated with a mean age of 61.16(SD = 12.84) years, 41.6% male, and 89.7% Caucasian. Mean change ranged from 7.29 to 8.41 for the PROMIS~? PF CAT, from 14.81 to 19.68 for the HOOS JR, and from 14.51 to 18.85 for the KOOS JR. ROC cut-offs ranged from 1.97-8.18 for the PF CAT, 6.33-43.36 for the HOOS JR, and 2.21-8.16 for the KOOS JR. Distribution-based methods estimated MCID values ranging from 2.45 to 21.55 for the PROMIS~? PF CAT; from 3.90 to 43.61 for the HOOS JR, and from 3.98 to 40.67 for the KOOS JR. The median MCID value in the range was similar to the mean change score for each measure and was 7.9 for the PF CAT, 18.0 for the HOOS JR, and 15.1 for the KOOS JR.CONCLUSION This is the first comprehensive study providing a wide range of MCIDs for the PROMIS? PF, HOOS JR, and KOOS JR in orthopaedic patients with joint ailments. 展开更多
关键词 Hhip DISABILITY and OSTEOARTHRITIS OUTCOME SCORE for JOINT reconstruction Patient-Reported OUTCOMES Measurement information System Physical Function Knee injury and OSTEOARTHRITIS OUTCOME SCORE for JOINT reconstruction Minimum clinically important difference JOINT Physical function Minimum detectable change Arthroplasty Orthopaedics Clinical OUTCOMES
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Research on Kalman Filtering Algorithmfor Deformation Information Series ofSimilar Single-Difference Model 被引量:10
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作者 吕伟才 徐绍铨 《Journal of China University of Mining and Technology》 2004年第2期189-194,199,共7页
Using similar single-difference methodology(SSDM) to solve the deformation values of the monitoring points, there is unstability of the deformation information series, at sometimes.In order to overcome this shortcomin... Using similar single-difference methodology(SSDM) to solve the deformation values of the monitoring points, there is unstability of the deformation information series, at sometimes.In order to overcome this shortcoming, Kalman filtering algorithm for this series is established,and its correctness and validity are verified with the test data obtained on the movable platform in plane. The results show that Kalman filtering can improve the correctness, reliability and stability of the deformation information series. 展开更多
关键词 similar single-difference methodology GPS deformation monitoring single epoch deformation information series Kalman filtering algorithm
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Difference of Visual Information Metric Based on Entropy of Primitive
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作者 Yanghong Zhang Feng Sun +3 位作者 Liwei Tian Jinfeng Li Longqing Zhang Shengfu Lan 《Computers, Materials & Continua》 SCIE EI 2020年第2期817-831,共15页
Image sparse representation is a method of efficient compression and coding of image signal in the process of digital image processing.Image after sparse representation,to enhance the transmission efficiency of the im... Image sparse representation is a method of efficient compression and coding of image signal in the process of digital image processing.Image after sparse representation,to enhance the transmission efficiency of the image signal.Entropy of Primitive(EoP)is a statistical representation of the sparse representation of the image,which indicates the probability of each base element.Based on the EoP,this paper presents an image quality evaluation method-Difference of Visual Information Metric(DVIM).The principle of this method is to evaluate the image quality with the difference between the original image and the distorted image.The comparative experiments between DVIM&PSNR&SSIM are carried out.It was found that there was a great improvement in the image quality evaluation of geometric changes.This method is an effective image quality evaluation method,which overcomes the weakness of other quality evaluation methods for geometrically changing images to a certain extent,and is more consistent with the subjective observation of the human eye. 展开更多
关键词 Entropy of primitive visual information visual information difference measurement
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Research on the Consumers Willingness to Buy Traceable Pork with Different Quality Information:A Case Study of Consumers in Weifang, Shandong Province 被引量:7
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作者 Fan BU Dian ZHU Linhai WU 《Asian Agricultural Research》 2013年第5期121-124,共4页
The traceability system can effectively reduce the food safety risks, however, it is confronted with various problems during its implementation. In this context, the paper carries out a case study of consumers in Weif... The traceability system can effectively reduce the food safety risks, however, it is confronted with various problems during its implementation. In this context, the paper carries out a case study of consumers in Weifang, Shandong Province, and studies their willingness to pay the traceable pork with different quality information. The results indicate that, the consumers show high expectations towards the introduction of traceability system, and they tend to buy the traceable pork only with breeding and slaughter information; their behaviors of purchase are greatly influenced by the following factors: the consumers education, age, income, attention on food safety and whether there are pregnant family members, etc.. 展开更多
关键词 FOOD safety differENT quality information Traceabl
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MFPL:Multi-Frequency Phase Difference Combination Based Device-Free Localization 被引量:1
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作者 Zengshan Tian Weiqin Yang +2 位作者 Yue Jin Liangbo Xie Zhengwen Huang 《Computers, Materials & Continua》 SCIE EI 2020年第2期861-876,共16页
With the popularity of indoor wireless network,device-free indoor localization has attracted more and more attention.Unlike device-based localization where the target is required to carry an active transmitter,their f... With the popularity of indoor wireless network,device-free indoor localization has attracted more and more attention.Unlike device-based localization where the target is required to carry an active transmitter,their frequent signal scanning consumes a large amount of energy,which is inconvenient for devices with limited energy.In this work,we propose the MFPL,device-free localization(DFL)system based on WiFi distance measurement.First,we combine multi-subcarrier characteristic of Channel State Information(CSI)with classical Fresnel reflection model to get the linear relationship between the change of the length of reflection path and the subcarrier phase difference.Then we calculate the Fresnel phase difference between subcarrier pairs with different spacing from CSI amplitude time series.Finally,we get the change of the length of the reflection path caused by target moving to achieve distance measurement and localization.Using a combination of subcarriers with different spacing to achieve distance measurement effectively broadens the maximum unambiguous distance of the system.To solve the complex non-linear problem of the intersection of two elliptic equations,we introduce Newton's method to transform the non-linear problem into a linear one.The effectiveness of our approach is verified using commodity WiFi infrastructures.The experimental results show our method achieves a median error of 0.87 m in actual indoor environment. 展开更多
关键词 Indoor localization WiFi channel state information fresnel phase difference reflection path length
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Similar Single-Difference Model and Its Algorithm for Solving GPS Monitoring Deformation Directly at Single Epoch 被引量:4
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作者 YUXuexiang XUShaoquan +1 位作者 GAOWei LüWeicai 《Geo-Spatial Information Science》 2003年第4期51-56,共6页
A new similar single-difference mathematical model (SS-DM) and its corresponding algorithmare advanced to solve the deformationof monitoring point directly in singleepoch. The method for building theSSDM is introduced... A new similar single-difference mathematical model (SS-DM) and its corresponding algorithmare advanced to solve the deformationof monitoring point directly in singleepoch. The method for building theSSDM is introduced in detail, and themain error sources affecting the accu-racy of deformation measurement areanalyzed briefly, and the basic algo-rithm and steps of solving the deform-ation are discussed.In order to validate the correctnessand the accuracy of the similar single-difference model, the test with fivedual frequency receivers is carried outon a slideway which moved in plane inFeb. 2001. In the test,five sessions areobserved. The numerical results oftest data show that the advanced mod-el is correct. 展开更多
关键词 运算法则 GPS 变形监测 数学模型
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Steganalysis of LSB Matching Using Characteristic Function Moment of Pixel Differences 被引量:1
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作者 Xianyi Chen Guangyong Gao +1 位作者 Dandan Liu Zhihua Xia 《China Communications》 SCIE CSCD 2016年第7期66-73,共8页
Nowadays,many steganographic tools have been developed,and secret messages can be imperceptibly transmitted through public networks.This paper concentrates on steganalysis against spatial least significant bit(LSB) ma... Nowadays,many steganographic tools have been developed,and secret messages can be imperceptibly transmitted through public networks.This paper concentrates on steganalysis against spatial least significant bit(LSB) matching,which is the prototype of many advanced information hiding methods.Many existing algorithms deal with steganalysis problems by using the dependencies between adjacent pixels.From another aspect,this paper calculates the differences among pixel pairs and proves that the histogram of difference values will be smoothed by stego noises.We calculate the difference histogram characteristic function(DHCF) and deduce that the moment of DHCFs(DHCFM) will be diminished after stego bits are hidden in the image.Accordingly,we compute the DHCFMs as the discriminative features.We calibrate the features by decreasing the influence of image content on them and train support vector machine classifiers based on the calibrated features.Experimental results demonstrate that the DHCFMs calculated with nonadjacent pixels are helpful to detect stego messages hidden by LSB matching. 展开更多
关键词 特征函数 相邻像素 矩匹配 LSB 差异分析 支持向量机分类器 应用 秘密信息
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New Method for Solving GPS Deformation Monitoring Information at Single Epoch 被引量:8
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作者 余学祥 徐绍铨 吕传才 《Journal of China University of Mining and Technology》 2003年第2期159-165,共7页
Based on the analyses for the characteristics of high precise GPS defor-mation monitor,according to the spatial relationship among the satellite, base point and monitoring point a new model and its corresponding algor... Based on the analyses for the characteristics of high precise GPS defor-mation monitor,according to the spatial relationship among the satellite, base point and monitoring point a new model and its corresponding algorithm were presented to solve the monitoring point deformation directly at single epoch. In this method the carrier phases is used as the basic observations, and the initial condition is precise baseline vectors obtained in the first period observations between the base point and monitoring point. This model is called the similar single difference model (SSDM). The main error sources effecting the accuracy of deformations were analyzed briefly, the single epoch algorithm of the receiver clock offset was advanced. The numerical results of test data show that the SSDM and the single epoch algorithm of receiver clock offset advanced are reliable and correct. 展开更多
关键词 GPS 信息失真 单差分模型 接收时钟补偿 算法 全球定位系统
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Study on Information Characters in Networked Mass Customization 被引量:1
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作者 GAN Yi QI Cong-qian GAN Li 《通讯和计算机(中英文版)》 2007年第1期61-67,共7页
关键词 网络客户化 信息流 信息不对称 信息差异
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Life Loss Estimation Based on Dam-Break Flood Uncertainties and Lack of Information in Mountainous Regions of Western China 被引量:1
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作者 Chao Wang Sherong Zhang +2 位作者 Yaosheng Tan Fei Pan Lei Yan 《Transactions of Tianjin University》 EI CAS 2017年第4期370-379,共10页
Compared with urban floods, dam-break floods are associated with greater uncertainties, including variable dam-break modes and hydrological characteristics, so conventional flood estimation methods cannot be directly ... Compared with urban floods, dam-break floods are associated with greater uncertainties, including variable dam-break modes and hydrological characteristics, so conventional flood estimation methods cannot be directly applied in the estimation of dam-break flood loss. In particular, there is scant information regarding the conditions of affected area and hydrological characteristics in southwest China. In this paper, we introduce an integrated model for estimating flood loss that is adapted to the mountainous regions of southwestern China in light of the relative lack of available information. This model has three major components: a basic information model, a dam-routed flood propagation simulation model, and a loss estimation model. We established the basic information model despite the relative lack of available information using 3S technology [remote sensing(RS); geographical information system(GIS); global positioning system(GPS)], data mining technology, and statistical analysis techniques. Our dam-routed flood propagation simulation model consists of major hydrologic processes and their governing equations for flow propagation, which we solve using finite-difference schemes. In this model, the flood propagation area is divided into grids and each grid is determined by the characteristic parameters obtained from the propagationsimulation. We present a case study of the Lianghekou hydropower station in Sichuan Province, China to illustrate the practical application of this integrated model for life loss estimation. 展开更多
关键词 Life loss ESTIMATION MODEL Lack of information DAM-BREAK FLOOD Basic information MODEL
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Research on Estimation of Time Delay Difference in Passive Locating for Impulse Signal
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作者 徐复 何文翔 +1 位作者 惠俊英 余赟 《Defence Technology(防务技术)》 SCIE EI CAS 2011年第3期167-175,共9页
Analyzed the relation between time delay difference and time delay estimation errors, based on the principles of three-point locating, a reformed threshold method for time delay difference estimation of impulse signal... Analyzed the relation between time delay difference and time delay estimation errors, based on the principles of three-point locating, a reformed threshold method for time delay difference estimation of impulse signals, called as amendment estimation for short, is developed by introducing channel equalization technique to its conventional version, named as direct estimation in this paper, to improve the estimation stability. After inherent relationship between time delay and phase shift of signals is analyzed, an integer period error compensation method utilized the diversities of both contribution share and contribution mode of concerned estimates is proposed under the condition of high precision phase lag estimation. Finally, a cooperative multi-threshold estimation method composed of amendment and direct estimations to process impulse signals with three thresholds is established. In sea trials data tests of passive locating, this method improves the estimation precision of time delay difference efficiently. The experiments verify the theoretical predictions. 展开更多
关键词 information processing technique PASSIVE locating for IMPULSE signal three point positioning time delay difference ESTIMATION amendment ESTIMATION INTEGER period error compensation cooperative MULTI-THRESHOLD ESTIMATION
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Influence of Cultural Differences on Advertisement Translation and Trademark Translation
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作者 于晓玮 《海外英语》 2014年第19期151-152,共2页
Advertisement translation and trademark translation are becoming more and more prevailing and influential under the increasing development of internationalization of business. This paper attempts to analyze the influe... Advertisement translation and trademark translation are becoming more and more prevailing and influential under the increasing development of internationalization of business. This paper attempts to analyze the influence of cultural differences on advertisement translation and trademark translation. It finds that advertisement translation and trademark translation are under the impressive influence of the differences between Chinese and Western cultures. This paper aims to stress the cultural differences in advertisement translation and trademark translation and reminds translators of the importance of noticing cultural differences and finding a proper point between foreign cultures and native cultures. 展开更多
关键词 CULTURAL differenceS INFLUENCE ADVERTISEMENT TRANS
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The Information Hiding Technology Based on the Similar Sample Blocks
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作者 Tzu-Chuen Lu Siang-Ru Liao Chun-Ming Chang 《通讯和计算机(中英文版)》 2012年第4期434-443,共10页
关键词 信息隐藏技术 样本块 类似 标准图像 个人形象 秘密信息 隐藏方法 灰度图像
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The Grade Difference Format and MGM^p (1,n) Optimization Model
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作者 Shemin Zhang Xiaojun Tong 《通讯和计算机(中英文版)》 2005年第7期37-41,共5页
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基于信息融合子域适应的不同工况下谐波减速器故障诊断方法
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作者 康守强 章炜东 +2 位作者 王玉静 刘连胜 孙宇林 《仪器仪表学报》 EI CAS CSCD 北大核心 2024年第3期60-71,共12页
针对工业机器人谐波减速器不同工况数据分布差异大,部分工况数据标签缺失以及单一传感器获取信息不全面,导致诊断准确率不高的问题,提出一种信息融合子域适应的不同工况下谐波减速器故障诊断方法。该方法将源域和目标域一维振动数据利... 针对工业机器人谐波减速器不同工况数据分布差异大,部分工况数据标签缺失以及单一传感器获取信息不全面,导致诊断准确率不高的问题,提出一种信息融合子域适应的不同工况下谐波减速器故障诊断方法。该方法将源域和目标域一维振动数据利用小波变换构建时频图;使用基于小波变换的图像融合方法整合多个传感器的时频信息并构建融合图像;提出多表示特征提取结构的改进残差网络以充分挖掘融合样本多表示特征,同时,在无监督场景下将源域和目标域融合样本的多表示特征进行子域适应处理,减小两域的各个子域间的分布差异,从而将知识从标签丰富的源域迁移到标签缺失的目标域,最终实现不同工况下谐波减速器的故障诊断。通过搭建工业机器人谐波减速器故障实验台并进行实测,所提方法在所有迁移任务中平均准确率可达98.8%,能够有效实现无监督场景中不同工况下谐波减速器的故障诊断。 展开更多
关键词 信息融合 不同工况 域适应 谐波减速器 故障诊断
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战略差异度、技术创新与企业全要素生产率——来自A股上市公司的经验证据
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作者 盛明泉 龙卉卉 鲍群 《河南师范大学学报(哲学社会科学版)》 北大核心 2024年第2期30-38,F0002,共10页
战略差异度对企业的影响是学术界关注的重要问题,而企业能否通过加大战略差异度进而提升全要素生产率为研究企业战略决策方面提供了不同的切入点。采用2009-2020年沪深A股上市公司的数据样本,实证检验了战略差异度对企业全要素生产率的... 战略差异度对企业的影响是学术界关注的重要问题,而企业能否通过加大战略差异度进而提升全要素生产率为研究企业战略决策方面提供了不同的切入点。采用2009-2020年沪深A股上市公司的数据样本,实证检验了战略差异度对企业全要素生产率的影响。研究结果表明,战略差异度对企业全要素生产率起到显著的正向作用,技术创新在战略差异度影响企业全要素生产率的传导路径上存在中介效应。进一步研究发现,高行业竞争水平、高信息透明度和低融资约束企业的战略差异度越大对全要素生产率的正向作用越显著。研究丰富了全要素生产率的相关文献,并为其提供了研究的新视角。同时有助于企业利益相关者理解战略决策的经济后果,对指导和促进企业进行战略变革及获取竞争优势提供理论参考。 展开更多
关键词 战略差异度 全要素生产率 技术创新 行业竞争水平 信息透明度
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学术履历差异对论文产出跨学科性影响研究——以图书情报领域核心作者为例
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作者 隗玲 黄茜 郭景芸 《现代情报》 北大核心 2024年第6期136-144,共9页
[目的/意义]以图书情报领域核心作者为研究对象,分析学术履历差异对其论文产出跨学科的影响,为制定科研人员管理与评价政策、建设高水平交叉科研队伍提供有价值的参考。[方法/过程]首先,通过核心期刊发文量识别出高发文量学者群体,并从... [目的/意义]以图书情报领域核心作者为研究对象,分析学术履历差异对其论文产出跨学科的影响,为制定科研人员管理与评价政策、建设高水平交叉科研队伍提供有价值的参考。[方法/过程]首先,通过核心期刊发文量识别出高发文量学者群体,并从中识别出核心学者作为目标学者;其次,采集目标学者的简历信息进行学术履历差异编码,收集论文成果信息测度其最高学历毕业5年内学术论文产出的跨学科性,计算均值后得到学者跨学科性指标;最后,通过相关性分析、多元回归分析探讨学术履历差异与学者跨学科性的关系。[结果/结论]结果表明,在学者年龄较小、毕业时间较近、学术发展背景存在差异、职业发展背景存在差异的情况下,学者会更倾向于进行跨学科研究。其中学术发展背景差异会促使学者进行跨学科研究,但并不直接影响其产出跨学科程度。而毕业时间、职业发展背景的差异会对学者论文产出的跨学科性程度造成影响。 展开更多
关键词 跨学科 履历分析 科研产出 图书情报领域 学术履历差异 论文产出
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依时序跨文体:苏轼作品阅读方式的一种尝试
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作者 康光磊(译) 谭静(校) 《长江学术》 2024年第3期66-76,共11页
苏轼喜欢对同一主题进行跨文体创作,即在同一时间对同一件事用不同文体多角度表达他的看法和感受。因不同文体承袭不同传统,有其自身套路,难免影响作者处理话题的态度和格调,这在以往常被忽略,对此有必要尝试依时序跨文体重读苏轼作品... 苏轼喜欢对同一主题进行跨文体创作,即在同一时间对同一件事用不同文体多角度表达他的看法和感受。因不同文体承袭不同传统,有其自身套路,难免影响作者处理话题的态度和格调,这在以往常被忽略,对此有必要尝试依时序跨文体重读苏轼作品。苏轼散文体的尺牍、题跋和杂记的数量庞大,是其作品中被忽视的宝藏。通过对苏轼诗与非正式散文文体差异的多重考察,探讨不同文体对作家表现同一事件方式的影响。对于苏轼在不同文体中处理相同主题或事件,不能简单解释为作家热衷在每个新作中都变换手法和方式。文学形式本身,或者至少是苏轼使用它们的方式,对结果产生着巨大的影响。当苏轼从一种形式转向另一种形式时,参照系随之改变,他对主题的处理也随之改变。 展开更多
关键词 苏轼 依时序 跨文体 非正式散文 文体差异
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个人健康信息管理视角下社群性量化自我参与对健康行为改变的影响研究 被引量:1
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作者 徐孝婷 朱庆华 王雷 《情报杂志》 北大核心 2024年第2期162-169,176,共9页
[研究目的]从PHIM视角下揭示社群性量化自我参与对健康行为改变的影响机理并尝试设计数据呈现方式来探索其影响效应,以便更好地指导群体性健康管理的实施。[研究方法]结合被试招募及对照实验,通过ANCOVA和回归分析尝试探索并验证社群性... [研究目的]从PHIM视角下揭示社群性量化自我参与对健康行为改变的影响机理并尝试设计数据呈现方式来探索其影响效应,以便更好地指导群体性健康管理的实施。[研究方法]结合被试招募及对照实验,通过ANCOVA和回归分析尝试探索并验证社群性量化自我参与对个人健康行为改变的影响机理,且进一步分析不同数据呈现方式的影响。[研究结论]相比于仅获取量化自我时间的参与者(M=2.567,SD=0.891),可以完整了解个人和他人量化自我数据结果的参与者其健康行为改变意愿更高(M=5.322,SD=0.903);差异洞察具有中介作用(c’=0.306,P1=0.000<0.01;b=0.148,P=0.026<0.05),即社群性情景可以触发参与者的差异洞察,进而使得其健康行为改变意愿更明显;社会比较具有调节作用(T=6.209,P=0.000<0.001),即当数据呈现中包含社会性比较时,参与者的差异洞察和健康行为改变意愿更强烈。该研究在一定程度上丰富了量化自我的理论研究,同时对于从社群性视角指导公众实施个人健康信息管理具有一定参考价值。 展开更多
关键词 个人健康信息管理 量化自我 健康行为改变 差异洞察 社会比较
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