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Approximate querying between heterogeneous ontologies based on association matrix
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作者 康达周 徐宝文 +1 位作者 陆建江 汪鹏 《Journal of Southeast University(English Edition)》 EI CAS 2005年第1期1-5,共5页
An approximate approach of querying between heterogeneous ontology-basedinformation systems based on an association matrix is proposed. First, the association matrix isdefined to describe relations between concepts in... An approximate approach of querying between heterogeneous ontology-basedinformation systems based on an association matrix is proposed. First, the association matrix isdefined to describe relations between concepts in two ontologies. Then, a methodof rewriting queriesbased on the association matrix is presented to solve the ontology heterogeneity problem. Itrewrites the queries in one ontology to approximate queries in another ontology based on thesubsumption relations between concepts. The method also uses vectors to represent queries, and thencomputes the vectors with the association matrix; the disjoint relations between concepts can beconsidered by the results. It can get better approximations than the methods currently in use, whichdonot consider disjoint relations. The method can be processed by machines automatically. It issimple to implement and expected to run quite fast. 展开更多
关键词 semantic web information retrieval ONTOLOGY QUERY association matrix
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Bottom-up mining of XML query patterns to improve XML querying
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作者 Yi-jun BEI Gang CHEN +1 位作者 Jin-xiang DONG Ke CHEN 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第6期744-757,共14页
Querying XML data is a computationally expensive process due to the complex nature of both the XML data and the XML queries. In this paper we propose an approach to expedite XML query processing by caching the results... Querying XML data is a computationally expensive process due to the complex nature of both the XML data and the XML queries. In this paper we propose an approach to expedite XML query processing by caching the results of frequent queries. We discover frequent query patterns from user-issued queries using an efficient bottom-up mining approach called VBUXMiner. VBUXMiner consists of two main steps. First, all queries are merged into a summary structure named "compressed global tree guide" (CGTG). Second, a bottom-up traversal scheme based on the CGTG is employed to generate frequent query patterns. We use the frequent query patterns in a cache mechanism to improve the XML query performance. Experimental results show that our proposed mining approach outperforms the previous mining algorithms for XML queries, such as XQPMinerTID and FastXMiner, and that by caching the results of frequent query patterns, XML query performance can be dramatically improved. 展开更多
关键词 XML querying XML mining CACHING Data mining
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Querying e-Commerce in China
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《China's Foreign Trade》 2000年第5期10-12,共3页
关键词 BE querying e-Commerce in China
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Multidimensional Data Querying on Tree-Structured Overlay
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作者 XU Lizhen WANG Shiyuan 《Wuhan University Journal of Natural Sciences》 CAS 2006年第5期1367-1372,共6页
Multidimensional data query has been gaining much interest in database research communities in recent years, yet many of the existing studies focus mainly on ten tralized systems. A solution to querying in Peer-to-Pee... Multidimensional data query has been gaining much interest in database research communities in recent years, yet many of the existing studies focus mainly on ten tralized systems. A solution to querying in Peer-to-Peer(P2P) environment was proposed to achieve both low processing cost in terms of the number of peers accessed and search messages and balanced query loads among peers. The system is based on a balanced tree structured P2P network. By partitioning the query space intelligently, the amount of query forwarding is effectively controlled, and the number of peers involved and search messages are also limited. Dynamic load balancing can be achieved during space partitioning and query resolving. Extensive experiments confirm the effectiveness and scalability of our algorithms on P2P networks. 展开更多
关键词 range query skyline query P2P indexing multi-dimensional data partition
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Bounded Evaluation:Querying Big Data with Bounded Resources
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作者 Yang Cao Wen-Fei Fan Teng-Fei Yuan 《International Journal of Automation and computing》 EI CSCD 2020年第4期502-526,共25页
This work aims to reduce queries on big data to computations on small data,and hence make querying big data possible under bounded resources.A query Q is boundedly evaluable when posed on any big dataset D,there exist... This work aims to reduce queries on big data to computations on small data,and hence make querying big data possible under bounded resources.A query Q is boundedly evaluable when posed on any big dataset D,there exists a fraction DQ of D such that Q(D)=Q(DQ),and the cost of identifying DQ is independent of the size of D.It has been shown that with an auxiliary structure known as access schema,many queries in relational algebra(RA)are boundedly evaluable under the set semantics of RA.This paper extends the theory of bounded evaluation to RAaggr,i.e.,RA extended with aggregation,under the bag semantics.(1)We extend access schema to bag access schema,to help us identify DQ for RAaggr queries Q.(2)While it is undecidable to determine whether an RAaggr query is boundedly evaluable under a bag access schema,we identify special cases that are decidable and practical.(3)In addition,we develop an effective syntax for bounded RAaggr queries,i.e.,a core subclass of boundedly evaluable RAaggr queries without sacrificing their expressive power.(4)Based on the effective syntax,we provide efficient algorithms to check the bounded evaluability of RAaggr queries and to generate query plans for bounded RAaggr queries.(5)As proof of concept,we extend PostgreSQL to support bounded evaluation.We experimentally verify that the extended system improves performance by orders of magnitude. 展开更多
关键词 Bounded evaluation resource-bounded query processing effective syntax access schema BOUNDEDNESS
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Querying over Fuzzy Description Logic
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作者 CHENG Jingwei MA Zongmin YAN Li WANG Hailong 《Wuhan University Journal of Natural Sciences》 CAS 2008年第4期429-434,共6页
Description logics (DLs) play an important role in representing and reasoning domain knowledge. Conjunctive queries stemmed from the domain of relational databases, and have attracted more attentions in semantic Web... Description logics (DLs) play an important role in representing and reasoning domain knowledge. Conjunctive queries stemmed from the domain of relational databases, and have attracted more attentions in semantic Web recently. To acquire a tractable DL for query answering, DL-Lite is proposed. Due to the large amount of imprecision and uncertainty in the real world, it is essential to extend DLs to deal with these vague and imprecise information. We thus propose a new fuzzy DL f-DLR-Lite.n, which allows for the presence of n-ary relations and the occurrence of concept conjunction on the left land of inclusion axioms. We also suggest an improved fuzzy query language, which supports the presence of thresholds and user defined weights. We also show that the query answering algorithm over the extended DL is still FOL reducible and shows polynomial data complexity. DL f-DLR-Lite,n can make up for the disadvantages of knowledge representation and reasoning of classic DLs, and the enhanced query language expresses user intentions more precisely and reasonably. 展开更多
关键词 query answering fuzzy set description logics
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A Database Querying Language for Formulating Relational Queries on Small Devices
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作者 Ahmad Rohiza Abdul-Kareem Sameem 《Computer Technology and Application》 2011年第3期172-181,共10页
For small devices like the PDAs and mobile phones, formulation of relational database queries is not as simple as using conventional devices such as the personal computers and laptops. Due to the restricted size and r... For small devices like the PDAs and mobile phones, formulation of relational database queries is not as simple as using conventional devices such as the personal computers and laptops. Due to the restricted size and resources of these smaller devices, current works mostly limit the queries that can be posed by users by having them predetermined by the developers. This limits the capability of these devices in supporting robust queries. Hence, this paper proposes a universal relation based database querying language which is targeted for small devices. The language allows formulation of relational database queries that uses minimal query terms. The formulation of the language and its structure will be described and usability test results will be presented to support the effectiveness of the language. 展开更多
关键词 DATABASE query language relational queries small devices.
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Chinese college students' Web querying behaviors:A case study of Peking University
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作者 QU Peng LIU Chang LAI Maosheng 《Chinese Journal of Library and Information Science》 2010年第4期23-36,共14页
This study examined users' querying behaviors based on a sample of 30 Chinese college students from Peking University. The authors designed 5 search tasks and each participant conducted two randomly selected searc... This study examined users' querying behaviors based on a sample of 30 Chinese college students from Peking University. The authors designed 5 search tasks and each participant conducted two randomly selected search tasks during the experiment. The results show that when searching for pre-designed search tasks, users often have relatively clear goals and strategies before searching. When formulating their queries, users often select words from tasks, use concrete concepts directly, or extract 'central words' or keywords. When reformulating queries, seven query reformulation types were identified from users' behaviors, i.e. broadening, narrowing, issuing new query, paralleling, changing search tools, reformulating syntax terms, and clicking on suggested queries. The results reveal that the search results and/or the contexts can also influence users' querying behaviors. 展开更多
关键词 Web searching Query behavior Query formulation Query reformulation
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Querying dynamic communities in online social networks 被引量:2
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作者 Li WEIGANG Edans F.O.SANDES +2 位作者 Jianya ZHENG Alba C.M.A.de MELO Lorna UDEN 《Journal of Zhejiang University-Science C(Computers and Electronics)》 SCIE EI 2014年第2期81-90,共10页
Online social networks(OSNs)offer people the opportunity to join communities where they share a common interest or objective.This kind of community is useful for studying the human behavior,diffusion of information,an... Online social networks(OSNs)offer people the opportunity to join communities where they share a common interest or objective.This kind of community is useful for studying the human behavior,diffusion of information,and dynamics of groups.As the members of a community are always changing,an efficient solution is needed to query information in real time.This paper introduces the Follow Model to present the basic relationship between users in OSNs,and combines it with the MapReduce solution to develop new algorithms with parallel paradigms for querying.Two models for reverse relation and high-order relation of the users were implemented in the Hadoop system.Based on 75 GB message data and 26 GB relation network data from Twitter,a case study was realized using two dynamic discussion communities:#musicmonday and#beatcancer.The querying performance demonstrates that the new solution with the implementation in Hadoop significantly improves the ability to find useful information from OSNs. 展开更多
关键词 Follow Model HADOOP MAPREDUCE querying TWITTER
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Querying Big Data: Bridging Theory and Practice 被引量:2
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作者 樊文飞 怀进鹏 《Journal of Computer Science & Technology》 SCIE EI CSCD 2014年第5期849-869,共21页
Big data introduces challenges to query answering, from theory to practice. A number of questions arise. What queries are "tractable" on big data? How can we make big data "small" so that it is feasible to find e... Big data introduces challenges to query answering, from theory to practice. A number of questions arise. What queries are "tractable" on big data? How can we make big data "small" so that it is feasible to find exact query answers?When exact answers are beyond reach in practice, what approximation theory can help us strike a balance between the quality of approximate query answers and the costs of computing such answers? To get sensible query answers in big data,what else do we necessarily do in addition to coping with the size of the data? This position paper aims to provide an overview of recent advances in the study of querying big data. We propose approaches to tackling these challenging issues,and identify open problems for future research. 展开更多
关键词 big data query answering TRACTABILITY APPROXIMATION data quality
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基于自适应Token池化与集合预测增强的目标检测
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作者 刘耀 陈东方 王晓峰 《计算机系统应用》 2025年第2期74-83,共10页
基于Transformer的目标检测算法往往存在着精度不足,收敛速度慢的问题.许多研究针对这些问题进行改进,取得了一定的成果.但是这些研究大都忽视了Transformer结构应用于目标检测领域时存在的两个不足之处.首先,自注意力运算结果缺乏多样... 基于Transformer的目标检测算法往往存在着精度不足,收敛速度慢的问题.许多研究针对这些问题进行改进,取得了一定的成果.但是这些研究大都忽视了Transformer结构应用于目标检测领域时存在的两个不足之处.首先,自注意力运算结果缺乏多样性.其次,因集合预测难度大,使得模型在匹配目标的过程中表现不稳定.为了弥补上述缺陷,首先设计了自适应token池化模块,增加自注意力权重的多样性.其次,设计了一种基于粗预测的锚框定位模块,并利用该模块为查询提供位置先验信息,从而提高二分图匹配过程的稳定性.最后,设计了基于组的去噪任务,通过训练模型对位于目标附近的正负查询进行区分,从而提高模型进行集合预测的能力.实验结果表明,本文提出的改进算法在COCO数据集上取得了较好的训练结果.与基线模型相比,改进算法在检测精度与收敛速度上有较大提升. 展开更多
关键词 目标检测 query初始化方式 自注意力 训练策略
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ASP.NET中参数传值的综合使用 被引量:7
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作者 钟世芬 柳荣其 +1 位作者 孙彪 周荣辉 《计算机应用研究》 CSCD 北大核心 2004年第11期212-214,共3页
在ASP.NET中传值的方式有许多种,典型的就是使用Application变量、Session变量,以及Querying,Cook ies,Forms进行传值。简单介绍了这几种方法及其优劣,讨论了在ASP.NET环境中的实际运用。
关键词 Application:Session querying COOKIES FORMS 参数
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Power Query与数据透视在工程计量自动汇总统计中的应用
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作者 季国军 陈华 +1 位作者 张佳龙 薛雯雯 《安装》 2025年第10期95-98,共4页
工程量计量与汇总统计工作贯穿于工程投标阶段、施工阶段和竣工阶段,工程计量后的汇总统计工作枯燥而繁琐,费时费力且容易出错,特别是当源数据发生变动时,汇总统计工作需重头再来,重复性机械性的人工汇总统计工作效率低下。本文结合实... 工程量计量与汇总统计工作贯穿于工程投标阶段、施工阶段和竣工阶段,工程计量后的汇总统计工作枯燥而繁琐,费时费力且容易出错,特别是当源数据发生变动时,汇总统计工作需重头再来,重复性机械性的人工汇总统计工作效率低下。本文结合实际项目案例,介绍了一种快速、准确、高效的工程量汇总统计方法,实现工程量计量汇总自动化更新,提高了工作效率与汇总统计的准确性。 展开更多
关键词 CAD POWER QUERY 数据透视 统计汇总 数据分析
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PAV-A-kNN: A Novel Approachable kNN Query Method in Road Network Environments
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作者 Kailai Zhou Weikang Xia Jiatai Wang 《Computers, Materials & Continua》 2025年第8期3217-3240,共24页
Ride-hailing(e.g.,DiDi andUber)has become an important tool formodern urban mobility.To improve the utilization efficiency of ride-hailing vehicles,a novel query method,called Approachable k-nearest neighbor(A-kNN),ha... Ride-hailing(e.g.,DiDi andUber)has become an important tool formodern urban mobility.To improve the utilization efficiency of ride-hailing vehicles,a novel query method,called Approachable k-nearest neighbor(A-kNN),has recently been proposed in the industry.Unlike traditional kNN queries,A-kNN considers not only the road network distance but also the availability status of vehicles.In this context,even vehicles with passengers can still be considered potential candidates for dispatch if their destinations are near the requester’s location.The V-Treebased query method,due to its structural characteristics,is capable of efficiently finding k-nearest moving objects within a road network.It is a currently popular query solution in ride-hailing services.However,when vertices to be queried are close in the graph but distant in the index,the V-Tree-based method necessitates the traversal of numerous irrelevant subgraphs,which makes its processing of A-kNN queries less efficient.To address this issue,we optimize the V-Tree-based method and propose a novel index structure,the Path-Accelerated V-Tree(PAV-Tree),to improve query performance by introducing shortcuts.Leveraging this index,we introduce a novel query optimization algorithm,PAVA-kNN,specifically designed to processA-kNNqueries efficiently.Experimental results showthat PAV-A-kNNachieves query times up to 2.2–15 times faster than baseline methods,with microsecond-level latency. 展开更多
关键词 k-nearest neighbor query ride-hailing services V-Tree shortest path
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Prospects and perils of ChatGPT in diabetes
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作者 Gumpeny R Sridhar Lakshmi Gumpeny 《World Journal of Diabetes》 2025年第3期1-7,共7页
ChatGPT,a popular large language model developed by OpenAI,has the potential to transform the management of diabetes mellitus.It is a conversational artificial intelligence model trained on extensive datasets,although... ChatGPT,a popular large language model developed by OpenAI,has the potential to transform the management of diabetes mellitus.It is a conversational artificial intelligence model trained on extensive datasets,although not specifically health-related.The development and core components of ChatGPT include neural networks and machine learning.Since the current model is not yet developed on diabetes-related datasets,it has limitations such as the risk of inaccuracies and the need for human supervision.Nevertheless,it has the potential to aid in patient engagement,medical education,and clinical decision support.In diabetes management,it can contribute to patient education,personalized dietary guidelines,and providing emotional support.Specifically,it is being tested in clinical scenarios such as assessment of obesity,screening for diabetic retinopathy,and provision of guidelines for the management of diabetic ketoacidosis.Ethical and legal considerations are essential before ChatGPT can be integrated into healthcare.Potential concerns relate to data privacy,accuracy of responses,and maintenance of the patient-doctor relationship.Ultimately,while ChatGPT and large language models hold immense potential to revolutionize diabetes care,one needs to weigh their limitations,ethical implications,and the need for human supervision.The integration promises a future of proactive,personalized,and patient-centric care in diabetes management. 展开更多
关键词 Large language models HALLUCINATIONS ETHICS QUERIES Accuracy Scholar GPT ChatGPT medical professional edition
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Few-Shot Learning for CT Lung Nodule Detection Based on Open-Set Object Detection
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作者 Lin-meng Li Huan Zhang +2 位作者 Hai-tao Yu Bin Cui Zhi-qun Wang 《Current Medical Science》 2025年第6期1358-1366,共9页
Objective This study aimed to develop a few-shot learning model for lung nodule detection in CT images by leveraging visual open-set object detection.Methods The Lung Nodule Analysis 2016(LUNA16)public dataset was use... Objective This study aimed to develop a few-shot learning model for lung nodule detection in CT images by leveraging visual open-set object detection.Methods The Lung Nodule Analysis 2016(LUNA16)public dataset was used for validation.It was split into training and testing sets in an 8:2 ratio.Classical You Only Look Once(YOLO)models of three sizes(n,m,x)were trained on the training set.Transfer learning experiments were then conducted using the mainstream open-set object detection models derived from Detection Transformer(DETR)with Improved DeNoising AnchOr Boxes(DINO),i.e.,Grounding DINO and Open-Vocabulary DINO(OV-DINO),as well as our proposed few-shot learning model,across a range of different shot sizes.Finally,all trained models were compared on the test set.Results After training on LUNA16,the precision,recall,and mean average precision(mAP)of the different-sized YOLO models showed no significant differences,with peak values of 82.8%,73.1%,and 77.4%,respectively.OV-DINO’s recall was significantly higher than YOLO’s,but it did not show clear advantages in precision or mAP.Using only one-fifth of the training samples and one-tenth of the training epochs,our proposed model outperformed both YOLO and OV-DINO,achieving improvements of 6.6%,9.3%,and 6.9%in precision,recall,and mAP,respectively,with final values of 89.4%,96.2%,and 87.7%.Conclusion The proposed few-shot learning model demonstrates stronger scene transfer capabilities,requiring fewer samples and training epochs,and can effectively improve the accuracy of lung nodule detection. 展开更多
关键词 Lung nodule CT imaging Open-set object detection Few-shot learning Vision query
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Reinforcement Learning for Time-Series Query Optimization
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作者 Songling Zou DongHua Yang +3 位作者 Mengmeng Li Haifeng Guo Hongqiang Wang Hongzhi Wang 《国际计算机前沿大会会议论文集》 2025年第1期271-281,共11页
Time-series databases(TSDBs)are essential for managing large-scale time-series data in fields like finance,IoT,and agriculture.However,traditional query optimization methods,such as dynamic programming,struggle with h... Time-series databases(TSDBs)are essential for managing large-scale time-series data in fields like finance,IoT,and agriculture.However,traditional query optimization methods,such as dynamic programming,struggle with high computational complexity and inaccurate cost estimates.This paper proposes a novel query optimization module for TSDBs using reinforcement learning(RL),specifically Deep Q-Networks(DQN)and Double Deep Q-Networks(DDQN).These algorithms dynamically learn optimal join orders based on query workloads and connection costs.Experiments show that RL-based methods achieve better optimization performance and stability compared to traditional heuristics,especially under complex cost models.This work highlights the potential of RL in improving query optimization for TSDBs. 展开更多
关键词 Distributed Indexing LSM-Tree Non-Primary Key Query
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LW-CQ:ML-Driven Cardinality Estimation for Complex Queries
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作者 Jiye Qiu DongHua Yang +3 位作者 Mengmeng Li Haifeng Guo Hongqiang Wang Hongzhi Wang 《国际计算机前沿大会会议论文集》 2025年第1期417-427,共11页
Cardinality estimation is crucial for query optimization,but traditional methods struggle with complex queries.We propose LW-CQ,a lightweight machine learning-based algorithm that improves cardinality estimation for c... Cardinality estimation is crucial for query optimization,but traditional methods struggle with complex queries.We propose LW-CQ,a lightweight machine learning-based algorithm that improves cardinality estimation for complex queries by enhancing the LW-XGB method.LW-CQ introduces four feature-level improvements and extends support for disjunctive queries and LIKE predicates.Experimental results show that LW-CQ achieves competitive accuracy while significantly reducing training and inference time,making it a promising solution for real-world database applications. 展开更多
关键词 Cardinality Estimation Machine Learning Complex Queries
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Excel Power Query在中小型企业批量生成记账凭证中的应用
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作者 钱伟彬 《当代会计》 2025年第9期178-180,共3页
聚焦于中小型企业,深入探讨借助Excel Power Query工具批量生成记账凭证的方法。通过分析中小型企业记账凭证处理的现状,对比手工录入的会计电算化记账方式(以下简称手工录账)与借助Excel Power Query批量生成记账凭证的模式,阐述Excel ... 聚焦于中小型企业,深入探讨借助Excel Power Query工具批量生成记账凭证的方法。通过分析中小型企业记账凭证处理的现状,对比手工录入的会计电算化记账方式(以下简称手工录账)与借助Excel Power Query批量生成记账凭证的模式,阐述Excel Power Query在数据处理各环节的应用优势,详细介绍应用该工具批量生成记账凭证的具体步骤,并结合实际案例展示其应用效果。 展开更多
关键词 Excel Power Query 记账凭证 批量生成 中小型企业
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Cryptanalysis and improvement to the quantum private query protocol for enhancing database privacy
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作者 Zhengda Shen Wenzhu Shao +4 位作者 Zhigang Li Xiaoyu Peng Nankun Mu Mahabubur Rahman Miraj Bin Liu 《Communications in Theoretical Physics》 2025年第6期122-128,共7页
In order to protect the privacy of the query user and database,some QKD-based quantum private query(QPQ)protocols were proposed.One example is the protocol proposed by Zhou et al,in which the user makes initial quantu... In order to protect the privacy of the query user and database,some QKD-based quantum private query(QPQ)protocols were proposed.One example is the protocol proposed by Zhou et al,in which the user makes initial quantum states and derives the key bit by comparing the initial quantum state and the outcome state returned from the database by ctrl or shift mode,instead of announcing two non-orthogonal qubits as others which may leak part secret information.To some extent,the security of the database and the privacy of the user are strengthened.Unfortunately,we find that in this protocol,the dishonest user could be obtained,utilizing unambiguous state discrimination,much more database information than that is analyzed in Zhou et al's original research.To strengthen the database security,we improved the mentioned protocol by modifying the information returned by the database in various ways.The analysis indicates that the security of the improved protocols is greatly enhanced. 展开更多
关键词 quantum private query quantum key distribution quantum cryptography
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