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Sentence,Phrase,and Triple Annotations to Build a Knowledge Graph of Natural Language Processing Contributions—A Trial Dataset 被引量:1
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作者 Jennifer D’Souza Sören Auer 《Journal of Data and Information Science》 CSCD 2021年第3期6-34,共29页
Purpose:This work aims to normalize the NLPCONTRIBUTIONS scheme(henceforward,NLPCONTRIBUTIONGRAPH)to structure,directly from article sentences,the contributions information in Natural Language Processing(NLP)scholarly... Purpose:This work aims to normalize the NLPCONTRIBUTIONS scheme(henceforward,NLPCONTRIBUTIONGRAPH)to structure,directly from article sentences,the contributions information in Natural Language Processing(NLP)scholarly articles via a two-stage annotation methodology:1)pilot stage-to define the scheme(described in prior work);and 2)adjudication stage-to normalize the graphing model(the focus of this paper).Design/methodology/approach:We re-annotate,a second time,the contributions-pertinent information across 50 prior-annotated NLP scholarly articles in terms of a data pipeline comprising:contribution-centered sentences,phrases,and triple statements.To this end,specifically,care was taken in the adjudication annotation stage to reduce annotation noise while formulating the guidelines for our proposed novel NLP contributions structuring and graphing scheme.Findings:The application of NLPCONTRIBUTIONGRAPH on the 50 articles resulted finally in a dataset of 900 contribution-focused sentences,4,702 contribution-information-centered phrases,and 2,980 surface-structured triples.The intra-annotation agreement between the first and second stages,in terms of F1-score,was 67.92%for sentences,41.82%for phrases,and 22.31%for triple statements indicating that with increased granularity of the information,the annotation decision variance is greater.Research limitations:NLPCONTRIBUTIONGRAPH has limited scope for structuring scholarly contributions compared with STEM(Science,Technology,Engineering,and Medicine)scholarly knowledge at large.Further,the annotation scheme in this work is designed by only an intra-annotator consensus-a single annotator first annotated the data to propose the initial scheme,following which,the same annotator reannotated the data to normalize the annotations in an adjudication stage.However,the expected goal of this work is to achieve a standardized retrospective model of capturing NLP contributions from scholarly articles.This would entail a larger initiative of enlisting multiple annotators to accommodate different worldviews into a“single”set of structures and relationships as the final scheme.Given that the initial scheme is first proposed and the complexity of the annotation task in the realistic timeframe,our intraannotation procedure is well-suited.Nevertheless,the model proposed in this work is presently limited since it does not incorporate multiple annotator worldviews.This is planned as future work to produce a robust model.Practical implications:We demonstrate NLPCONTRIBUTIONGRAPH data integrated into the Open Research Knowledge Graph(ORKG),a next-generation KG-based digital library with intelligent computations enabled over structured scholarly knowledge,as a viable aid to assist researchers in their day-to-day tasks.Originality/value:NLPCONTRIBUTIONGRAPH is a novel scheme to annotate research contributions from NLP articles and integrate them in a knowledge graph,which to the best of our knowledge does not exist in the community.Furthermore,our quantitative evaluations over the two-stage annotation tasks offer insights into task difficulty. 展开更多
关键词 Scholarly knowledge graphs Open science graphs Knowledge representation Natural language processing Semantic publishing
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Word Embeddings and Semantic Spaces in Natural Language Processing 被引量:2
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作者 Peter J. Worth 《International Journal of Intelligence Science》 2023年第1期1-21,共21页
One of the critical hurdles, and breakthroughs, in the field of Natural Language Processing (NLP) in the last two decades has been the development of techniques for text representation that solves the so-called curse ... One of the critical hurdles, and breakthroughs, in the field of Natural Language Processing (NLP) in the last two decades has been the development of techniques for text representation that solves the so-called curse of dimensionality, a problem which plagues NLP in general given that the feature set for learning starts as a function of the size of the language in question, upwards of hundreds of thousands of terms typically. As such, much of the research and development in NLP in the last two decades has been in finding and optimizing solutions to this problem, to feature selection in NLP effectively. This paper looks at the development of these various techniques, leveraging a variety of statistical methods which rest on linguistic theories that were advanced in the middle of the last century, namely the distributional hypothesis which suggests that words that are found in similar contexts generally have similar meanings. In this survey paper we look at the development of some of the most popular of these techniques from a mathematical as well as data structure perspective, from Latent Semantic Analysis to Vector Space Models to their more modern variants which are typically referred to as word embeddings. In this review of algoriths such as Word2Vec, GloVe, ELMo and BERT, we explore the idea of semantic spaces more generally beyond applicability to NLP. 展开更多
关键词 Natural Language processing Vector Space Models Semantic Spaces Word Embeddings Representation Learning Text Vectorization Machine Learning Deep Learning
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Natural Language Processing with Transformer-Based Models:A Meta-Analysis
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作者 Charles Munyao John Ndia 《Journal on Artificial Intelligence》 2025年第1期329-346,共18页
The natural language processing(NLP)domain has witnessed significant advancements with the emergence of transformer-based models,which have reshaped the text understanding and generation landscape.While their capabili... The natural language processing(NLP)domain has witnessed significant advancements with the emergence of transformer-based models,which have reshaped the text understanding and generation landscape.While their capabilities are well recognized,there remains a limited systematic synthesis of how these models perform across tasks,scale efficiently,adapt to domains,and address ethical challenges.Therefore,the aim of this paper was to analyze the performance of transformer-based models across various NLP tasks,their scalability,domain adaptation,and the ethical implications of such models.This meta-analysis paper synthesizes findings from 25 peer-reviewed studies on NLP transformer-based models,adhering to the PRISMA framework.Relevant papers were sourced from electronic databases,including IEEE Xplore,Springer,ACM Digital Library,Elsevier,PubMed,and Google Scholar.The findings highlight the superior performance of transformers over conventional approaches,attributed to selfattention mechanisms and pre-trained language representations.Despite these advantages,challenges such as high computational costs,data bias,and hallucination persist.The study provides new perspectives by underscoring the necessity for future research to optimize transformer architectures for efficiency,address ethical AI concerns,and enhance generalization across languages.This paper contributes valuable insights into the current trends,limitations,and potential improvements in transformer-based models for NLP. 展开更多
关键词 Natural language processing TRANSFORMERS pretrained language representations self-attention mechanisms ethical AI
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Improved Gabor transform and group sparse representation for ancient mural inpainting
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作者 ZHAO Mengxue CHEN Yong TAO Meifeng 《Journal of Measurement Science and Instrumentation》 2025年第3期384-394,共11页
Sparse representation has been highly successful in various tasks related to image processing and computer vision.For ancient mural image inpainting,traditional group sparse representation models usually lead to struc... Sparse representation has been highly successful in various tasks related to image processing and computer vision.For ancient mural image inpainting,traditional group sparse representation models usually lead to structure blur and line discontinuity due to the construction of similarity group solely based on the Euclidean distance and the randomness of dictionary initialization.To address the aforementioned issues,an improved curvature Gabor transform and group sparse representation(CGabor-GSR)model for ancient Dunhuang mural inpainting is proposed.To begin with,mutual information is introduced to weight the Euclidean distance,and then the weighted Euclidean distance acts as a new standard of similarity group.Subsequently,to mitigate the randomness of dictionary initialization,a curvature Gabor wavelet transform is proposed to extract the features and initialize the feature dictionary with dimension reduction based on principal component analysis(PCA).Ultimately,singular value decomposition(SVD)and split Bregman iteration(SBI)can be used to resolve the CGabor-GSR model to reconstruct the mural images.Experimental results on Dunhuang mural inpainting demonstrate tha the proposed CGabor-GSR achieves a better performance than compared algorithms in both objective and visual evaluation. 展开更多
关键词 digital image processing mural inpainting curvature Gabor wavelet transform group sparse representation mutual information
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视觉物体表征加工中背−腹通路的相互作用
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作者 高飞 蔡厚德 《心理科学进展》 北大核心 2026年第4期710-725,共16页
大脑的视觉系统通过背侧与腹侧通路加工物体的视觉信息。腹侧通路主要负责“是什么”(what)的物体视觉识别加工,背侧通路主要负责“在哪里”(where)的物体视空间与运动加工。但是,背−腹通路存在多重交互的神经连接,提示视觉物体表征加... 大脑的视觉系统通过背侧与腹侧通路加工物体的视觉信息。腹侧通路主要负责“是什么”(what)的物体视觉识别加工,背侧通路主要负责“在哪里”(where)的物体视空间与运动加工。但是,背−腹通路存在多重交互的神经连接,提示视觉物体表征加工中存在两者的功能相互作用。一方面,腹侧通路并不能单独计算物体的整体形状,背侧通路对物体整体形状的表征信息有必要与腹侧通路表征的物体局部特征信息汇合,以支持不变性的物体视觉信息加工;另一方面,在目标导向的思想和行为中,背侧通路需要实时提取和保持来自腹侧通路的物体视觉信息,以实现适应性的物体视觉信息加工。前者是一种主要受特征驱动(自下而上)的功能整合,而后者是一种主要受任务驱动(自上而下)的功能整合。未来还需深入研究注意对背侧通路表征物体整体形状的影响、物体熟悉性调节整体形状与局部特征整合的机制、视觉工作记忆如何抵抗干扰以保持对目标导向刺激的加工机制、内生记忆信息对适应性视觉物体表征的影响,以及背−腹通路的发育机制及其对两者相互作用的影响等。 展开更多
关键词 视觉物体表征 背−腹通路的相互作用 不变性的物体视觉信息加工 适应性的物体视觉信息加工
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随机地震动过程的小波降维表达
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作者 刘章军 周江林 +1 位作者 张伟 刘子心 《振动工程学报》 北大核心 2026年第2期403-412,共10页
基于确定性函数的小波变换,结合非平稳随机过程的谱分解理论,推导出其小波系数也是一个非平稳随机过程。在此基础上建立了小波系数的源谱表达,通过引入随机正交函数的降维方法,得到基于小波变换的非平稳随机过程降维表达。选取MH、MO及... 基于确定性函数的小波变换,结合非平稳随机过程的谱分解理论,推导出其小波系数也是一个非平稳随机过程。在此基础上建立了小波系数的源谱表达,通过引入随机正交函数的降维方法,得到基于小波变换的非平稳随机过程降维表达。选取MH、MO及MLP三种小波,针对它们的离散方式和尺度范围,通过比较分析确定了最优方案。实现了采用两个基本随机变量即可生成地震动加速度过程的代表性样本集合。算例表明,本文方法在精度和非平稳性方面优于传统谱表示方法,并通过与实测强震记录拟合验证了该方法的工程适用性。值得说明的是,降维方法是一种全概率方法,即生成的数百条代表性样本可构成一个完备的概率集,为结合概率密度演化理论进行复杂工程结构的精细化抗震分析奠定了基础。 展开更多
关键词 非平稳过程 小波变换 演变功率谱 随机正交函数 降维表达
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采用双仿射注意力的英文AMR解析模型
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作者 尤海滨 许晶晶 +1 位作者 康泽民 王华珍 《华侨大学学报(自然科学版)》 2026年第2期213-221,共9页
针对抽象语义表示(AMR)解析在复杂句法与长距离依赖,尤其是主从层次关系建模不足的问题,提出结合双仿射注意力与多通道图卷积网络(GCN)的端到端模型。首先,通过双仿射注意力对词对进行关系特定打分,构建按关系类型分通道的邻接张量;然后... 针对抽象语义表示(AMR)解析在复杂句法与长距离依赖,尤其是主从层次关系建模不足的问题,提出结合双仿射注意力与多通道图卷积网络(GCN)的端到端模型。首先,通过双仿射注意力对词对进行关系特定打分,构建按关系类型分通道的邻接张量;然后,多通道图卷积在各通道上进行消息传递并跨通道聚合,生成结构感知的节点表示。结果表明:在AMR 2.0、AMR 3.0数据集上的Smatch分别为85.6、84.3,相较于基线模型SPRING,分别提升了1.8%、2.6%;文中模型能够更准确地捕捉层次化依赖与头尾关系,在复杂句法场景下表现出良好的稳健性与应用潜力。 展开更多
关键词 语义解析 抽象语义表示 序列到序列模型 自然语言处理
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Gelfand三元组上分式Lévy过程的新息表示(英文)
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作者 吕学斌 万建平 《应用数学》 CSCD 北大核心 2009年第2期443-447,共5页
借助于分式积分-微分算子和关于Gelfand三元组上分式Lévy过程的随机积分,本文给出分式Lévy过程的新息表示公式,此公式可将Gelfand三元组上分式Lévy过程转换成更简单的L啨vy过程,并且可以应用在信号识别和行为金融学中.
关键词 Gelfand三元组 LÉVY过程 分式Lévy过程 新息表示
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基于多源信息的专利分类研究
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作者 何宏 姚致远 +2 位作者 陈信 俞东进 刘锋光 《科技管理研究》 2026年第4期142-155,共14页
传统的专利分类方法主要聚焦专利文本信息,忽视了其他元数据信息的应用。为提升专利分类对技术创新与产业发展的促进作用,本文提出了一种新型的专利分类模型MinPac,综合运用包括文本信息和元数据信息在内的多源信息,从多维度提升专利分... 传统的专利分类方法主要聚焦专利文本信息,忽视了其他元数据信息的应用。为提升专利分类对技术创新与产业发展的促进作用,本文提出了一种新型的专利分类模型MinPac,综合运用包括文本信息和元数据信息在内的多源信息,从多维度提升专利分类的性能。具体而言,MinPac模型使用卷积神经网络处理专利文本,生成文本分类分数;根据专利受让人、发明人、审核人和引用信息等元数据信息构建异构图,使用图采样与聚合算法处理异构图,生成图结构分类分数;对两种分类分数平均池化得到最终分类分数。实验结果表明,MinPac模型在所有指标上的结果都优于其他的基线方法,尤其是在Precision@1和NDCG@1这两个指标上实现了5.9%的性能提升。因此,专利分类应突破单一文本分析的框架,系统地融合技术内容、人员协作与审查行为等多维度信息,方能更精准地刻画专利的技术归属与创新脉络。MinPac模型在提高专利分类性能方面具有显著优势,在促进专利信息的社会科学应用方面具有较大潜力,可为相关领域的政策制定、产业分析和学术研究提供新的视角和方法论。 展开更多
关键词 专利分类 文本分类 图表示学习 专利文本 元数据信息 多源信息融合 自然语言处理
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基于孪生Transformer的业务流程异常检测方法
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作者 潘克旭 方娜 《计算机应用研究》 北大核心 2026年第2期463-471,共9页
业务流程异常检测对于风险管理和流程优化至关重要,业务流程复杂的动态性使事件日志的异常模式识别困难。现有无监督方法缺乏对事件间深层语义的捕获,且模型训练易受噪声影响。鉴于此,提出了一种融合了语义信息和序列信息的基于孪生Tran... 业务流程异常检测对于风险管理和流程优化至关重要,业务流程复杂的动态性使事件日志的异常模式识别困难。现有无监督方法缺乏对事件间深层语义的捕获,且模型训练易受噪声影响。鉴于此,提出了一种融合了语义信息和序列信息的基于孪生Transformer的少样本异常检测方法(Sia-Transformer)。该方法基于局部离群因子算法提取少量高置信正常和异常样本构建对比关系,挖掘样本间的语义差异性;随后使用采样策略构建训练样本对,同时筛选锚点样本集合,将样本对输入孪生Transformer编码器捕获序列信息并学习流程实例间的行为相似性;最后,利用预训练模型量化待测样本与锚点集的行为相似性,将高于阈值的样本判定为异常。在多个公开真实事件日志数据集上的实验评估表明,该方法在案例级异常检测方面的F1分数优于现有基准方法。此外,通过在训练数据中逐渐引入噪声的实验,验证了该方法对于训练数据的污染具有鲁棒性。 展开更多
关键词 业务流程异常检测 少样本学习 孪生Transformer 语义表征 鲁棒性
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基于改进双向变换器模型的智能变电站虚回路自动校核研究
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作者 陈文汉 赵张磊 +2 位作者 高炳蔚 陈刚 孔凡坊 《电气技术》 2026年第2期61-67,共7页
智能变电站的虚回路连接正确性关系到智能变电站继电保护设备能否正确动作,传统的虚回路校核依赖人工逐项对比,检验效果差、时间长。本文提出一种基于改进双向变换器(BERT)模型的智能变电站虚回路自动校核技术。首先通过语句清洗提高校... 智能变电站的虚回路连接正确性关系到智能变电站继电保护设备能否正确动作,传统的虚回路校核依赖人工逐项对比,检验效果差、时间长。本文提出一种基于改进双向变换器(BERT)模型的智能变电站虚回路自动校核技术。首先通过语句清洗提高校核精准度,然后通过掩盖中文词汇代替BERT模型中掩盖单个字符的方式,增强模型的中文词汇理解性能。为进一步提高辨识性能,结合词汇遮掩模式的BERT模型和孪生网络结构得到改进BERT模型,并将虚端子描述文本分成两个同语义子集作为改进BERT模型的输入,通过计算虚回路端子两端文本的余弦相似度来校核虚端子连接正确性。测试与应用结果显示,该方法能够准确识别虚端子匹配度并自动校核虚回路,有效降低了传统虚回路校核的工作量,提升了虚回路校核的准确性。 展开更多
关键词 虚回路校核 双向变换器(BERT) 自然语言处理 智能变电站
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基于文化仿生理念的彝族文创品牌设计研究
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作者 马沼印 韦含书 马霄骁 《设计艺术研究》 2026年第1期168-176,共9页
在彝族文化体系中,自然造物理念对区域发展和民众生活产生了深刻影响,大多数传统纹样取材于自然,并以形态仿生的方式塑造出独特的民族符号和文化意象。为探究文化仿生理念在彝族文创设计中的应用逻辑,构建具有文化辨识度的民族文创品牌... 在彝族文化体系中,自然造物理念对区域发展和民众生活产生了深刻影响,大多数传统纹样取材于自然,并以形态仿生的方式塑造出独特的民族符号和文化意象。为探究文化仿生理念在彝族文创设计中的应用逻辑,构建具有文化辨识度的民族文创品牌,文章基于田野考察,剖析彝族本土文化基因库中的视觉符号与精神内涵,并结合现实案例探讨当下彝族文创品牌的发展趋势,通过AHP层次分析法构建用户需求评价模型,验证彝族文创品牌设计过程中的核心影响因素与作用效能,以设计实践的形式创作出符合市场需求和大众审美的文创品牌产品。研究证明,文化仿生理念的融合应用不仅能够激活彝族文化的内生创造力,更通过符号形象塑造了具有情感共鸣的文化叙事体系,为民族本土文创设计的创新性发展提供了理论参照与实践经验。 展开更多
关键词 文化仿生 彝族纹饰 符号象征 需求层次分析 文创品牌设计
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Ultrasonic Nondestructive Signals Processing Based on Matching Pursuit with Gabor Dictionary 被引量:8
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作者 GUO Jinku WU Jinying +1 位作者 YANG Xiaojun LIU Guangbin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第4期591-595,共5页
The success of ultrasonic nondestructive testing technology depends not only on the generation and measurement of the desired waveform, but also on the signal processing of the measured waves. The traditional time-dom... The success of ultrasonic nondestructive testing technology depends not only on the generation and measurement of the desired waveform, but also on the signal processing of the measured waves. The traditional time-domain methods have been partly successful in identifying small cracks, but not so successful in estimating crack size, especially in strong backscattering noise. Sparse signal representation can provide sparse information that represents the signal time-frequency signature, which can also be used in processing ultrasonic nondestructive signals. A novel ultrasonic nondestructive signal processing algorithm based on signal sparse representation is proposed. In order to suppress noise, matching pursuit algorithm with Gabor dictionary is selected as the signal decomposition method. Precise echoes information, such as crack location and size, can be estimated by quantitative analysis with Gabor atom. To verify the performance, the proposed algorithm is applied to computer simulation signal and experimental ultrasonic signals which represent multiple backscattered echoes from a thin metal plate with artificial holes. The results show that this algorithm not only has an excellent performance even when dealing with signals in the presence of strong noise, but also is successful in estimating crack location and size. Moreover, the algorithm can be applied to data compression of ultrasonic nondestructive signal. 展开更多
关键词 ultrasonic signal processing sparse representation matching pursuit Gabor dictionary
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DOA estimation of coexisted noncoherent and coherent signals via sparse representation of cleaned array covariance matrix 被引量:3
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作者 刘威 徐友根 刘志文 《Journal of Beijing Institute of Technology》 EI CAS 2013年第2期241-245,共5页
A new direction finding method is presented to deal with coexisted noncoherent and co- herent signals without smoothing operation. First the direction-of-arrival (DOA) estimation task is herein reformulated as a spa... A new direction finding method is presented to deal with coexisted noncoherent and co- herent signals without smoothing operation. First the direction-of-arrival (DOA) estimation task is herein reformulated as a sparse reconstruction problem of the cleaned array covariance matrix, which is processed to eliminate the affection of the noise. Then by using the block of matrices, the information of DOAs which we pursuit are implied in the sparse coefficient matrix. Finally, the sparse reconstruction problem is solved by the improved M-FOCUSS method, which is applied to the situation of block of matrices. This method outperforms its data domain counterpart in terms of noise suppression, and has a better performance in DOA estimation than the customary spatial smoothing technique. Simulation results verify the efficacy of the proposed method. 展开更多
关键词 direction-of-arrival DOA estimation sparse representation multipath propagation array signal processing
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New Approach for Solving Master Equations in Quantum Optics and Quantum Statistics by Virtue of Thermo-Entangled State Representation 被引量:11
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作者 FAN Hong-Yi HU Li-Yun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第4期729-742,共14页
By introducing a fictitious mode to be a counterpart mode of the system mode under review we introduce the entangled state representation (η|, which can arrange master equations of density operators p(t) in quant... By introducing a fictitious mode to be a counterpart mode of the system mode under review we introduce the entangled state representation (η|, which can arrange master equations of density operators p(t) in quantum statistics as state-vector evolution equations due to the elegant properties of (η|. In this way many master equations (respectively describing damping oscillator, laser, phase sensitive, and phase diffusion processes with different initial density operators) can be concisely solved. Specially, for a damping process characteristic of the decay constant k we find that the matrix element of p(t) at time t in 〈η| representation is proportional to that of the initial po in the decayed entangled state (ηe^-kt| representation, accompanying with a Gaussian damping factor. Thus we have a new insight about the nature of the dissipative process. We also set up the so-called thermo-entangled state representation of density operators, ρ = f(d^2η/π)(η|ρ〉D(η), which is different from all the previous known representations. 展开更多
关键词 master equation fictitious mode thermo-entangled state representation damping oscillator and laser phase sensitive and phase diffusion processes
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Virtual Reality Based Process Integrated Simulation Platform in Refinery:Virtual Refinery and Its Application 被引量:6
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作者 Zhou Zewei Feng Yiping +1 位作者 Rong Gang Wu Yucheng 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2011年第3期74-84,共11页
With the combination between system simulation and virtual reality,we have established an integrated virtual refinery simulation platform,and analyzed the overall design and principal architecture.This paper introduce... With the combination between system simulation and virtual reality,we have established an integrated virtual refinery simulation platform,and analyzed the overall design and principal architecture.This paper introduces a simulation algorithm about a refinery based on virtual reality,and explains how the algorithm can be applied to the virtual refinery integrated simulation platform in detail.The virtual refinery simulation platform,which consists of a three-dimensional scene system,an integrated database system and a dynamic-static simulation system,has many applications,such as dynamic-static simulation of key process unit used as process control and oil tank blending simulation for scheduling.With the visualization and human-computer interaction for acquiring production and process data,this platform can provide effective supports on staff training related with monitoring,control and operation in refinery.Virtual refinery can also be web published through the internet and it is helpful for the distance training and education. 展开更多
关键词 virtual refinery petrochemical enterprise process integrated simulation information representation intelligent manufacturing systems
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Analytical and numerical investigations of displaced thermal state evolutions in a laser process 被引量:2
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作者 杜传勋 孟祥国 +1 位作者 张冉 王继锁 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第12期102-108,共7页
We investigate how displaced thermal states (DTSs) evolve in a laser channel. Remarkably, the initial DTS, an example of a mixed state, still remains mixed and thermal. At long times, they finally decay to a highly ... We investigate how displaced thermal states (DTSs) evolve in a laser channel. Remarkably, the initial DTS, an example of a mixed state, still remains mixed and thermal. At long times, they finally decay to a highly classical thermal field only related to the laser parameters κ and g. The normal ordering product of density operator of the DTS in the laser channel leads to obtaining the analytical time-evolution expressions of the photon number, Wigner function, and von Neumann entropy. Also, some interesting results are presented via numerically investigating these explicit time-dependent expressions. 展开更多
关键词 displaced thermal state laser process infinitive operator-sum representation photon number Wigner function von Neumann entropy
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Survival probability and ruin probability of a risk model 被引量:1
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作者 LUO Jian-hua 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2008年第3期256-264,共9页
In this paper,a new risk model is studied in which the rate of premium income is regarded as a random variable,the arrival of insurance policies is a Poisson process and the process of claim occurring is p-thinning pr... In this paper,a new risk model is studied in which the rate of premium income is regarded as a random variable,the arrival of insurance policies is a Poisson process and the process of claim occurring is p-thinning process.The integral representations of the survival probability are gotten.The explicit formula of the survival probability on the infinite interval is obtained in the special casc cxponential distribution.The Lundberg inequality and the common formula of the ruin probability are gotten in terms of some techniques from martingale theory. 展开更多
关键词 risk model thinning process survival probability MARTINGALE ruin probability integral representation
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On existence and uniqueness of solutions to uncertain backward stochastic differential equations
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作者 FEI Wei-yin 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2014年第1期53-66,共14页
This paper is concerned with a class of uncertain backward stochastic differential equations (UBSDEs) driven by both an m-dimensional Brownian motion and a d-dimensional canonical process with uniform Lipschitzian c... This paper is concerned with a class of uncertain backward stochastic differential equations (UBSDEs) driven by both an m-dimensional Brownian motion and a d-dimensional canonical process with uniform Lipschitzian coefficients. Such equations can be useful in mod- elling hybrid systems, where the phenomena are simultaneously subjected to two kinds of un- certainties: randomness and uncertainty. The solutions of UBSDEs are the uncertain stochastic processes. Thus, the existence and uniqueness of solutions to UBSDEs with Lipschitzian coeffi- cients are proved. 展开更多
关键词 Uncertain backward stochastic differential equations(UBSDEs) canonical process existence and uniqueness Lipschitzian condition martingale representation theorem
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Overlapped Rectangle Image Representation and Its Application to Exact Legendre Moments Computatio
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作者 HUANG Wei CHEN Chuanbo SAREM Mudar ZHENG Yunping 《Geo-Spatial Information Science》 2008年第4期294-301,共8页
Linear quadtree is a popular image representation method due to its convenient imaging procedure. However, the excessive emphasis on the symmetry of segmentation, i.e. dividing repeatedly a square into four equal sub-... Linear quadtree is a popular image representation method due to its convenient imaging procedure. However, the excessive emphasis on the symmetry of segmentation, i.e. dividing repeatedly a square into four equal sub-squares, makes linear quadtree not an optimal representation. In this paper, a no-loss image representation, referred to as Overlapped Rectangle Image Representation (ORIR), is presented to support fast image operations such as Legendre moments computation. The ORIR doesn’t importune the symmetry of segmentation, and it is capable of representing, by using an identical rectangle, the information of the pixels which are not even adjacent to each other in the sense of 4-neighbor and 8-neighbor. Hence, compared with the linear quadtree, the ORIR significantly reduces the number of rectangles required to represent an image. Based on the ORIR, an algorithm for exact Legendre moments computation is presented. The theoretical analysis and the experimental results show that the ORIR-based algorithm for exact Legendre moments computation is faster than the conventional exact algorithms. 展开更多
关键词 image processing image representation Legendre moments computation
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