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Product Data Model for Performance-driven Design 被引量:2
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作者 Guang-Zhong Hu Xin-Jian Xu +2 位作者 Shou-Ne Xiao Guang-Wu Yang Fan Pu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第5期1112-1122,共11页
When designing large-sized complex machinery products, the design focus is always on the overall per- formance; however, there exist no design theory and method based on performance driven. In view of the defi- ciency... When designing large-sized complex machinery products, the design focus is always on the overall per- formance; however, there exist no design theory and method based on performance driven. In view of the defi- ciency of the existing design theory, according to the performance features of complex mechanical products, the performance indices are introduced into the traditional design theory of "Requirement-Function-Structure" to construct a new five-domain design theory of "Client Requirement-Function-Performance-Structure-Design Parameter". To support design practice based on this new theory, a product data model is established by using per- formance indices and the mapping relationship between them and the other four domains. When the product data model is applied to high-speed train design and combining the existing research result and relevant standards, the corresponding data model and its structure involving five domains of high-speed trains are established, which can provide technical support for studying the relationships between typical performance indices and design parame- ters and the fast achievement of a high-speed train scheme design. The five domains provide a reference for the design specification and evaluation criteria of high speed train and a new idea for the train's parameter design. 展开更多
关键词 Complex product design Performance driven data model Mapping relationship High-speed train
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Statecharts for Distributed Product Data Management System Modelling
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作者 K K Leong K M Yu W B Lee 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期260-261,共2页
Product data management (PDM) has been accepted as an important tool for the manufacturing industries. In recent years, more and mor e researches have been conducted in the development of PDM. Their research area s in... Product data management (PDM) has been accepted as an important tool for the manufacturing industries. In recent years, more and mor e researches have been conducted in the development of PDM. Their research area s include system design, integration of object-oriented technology, data distri bution, collaborative and distributed manufacturing working environment, secur ity, and web-based integration. However, there are limitations on their rese arches. In particular, they cannot cater for PDM in distributed manufacturing e nvironment. This is especially true in South China, where many Hong Kong (HK) ma nufacturers have moved their production plants to different locations in Pearl R iver Delta for cost reduction. However, they retain their main offices in HK. Development of PDM system is inherently complex. Product related data cover prod uct name, product part number (product identification), drawings, material speci fications, dimension requirement, quality specification, test result, log size, production schedules, product data version and date of release, special tooling (e.g. jig and fixture), mould design, project engineering in charge, cost spread sheets, while process data includes engineering release, engineering change info rmation management, and other workflow related to the process information. Accor ding to Cornelissen et al., the contemporary PDM system should contains manageme nt functions in structure, retrieval, release, change, and workflow. In system design, development and implementation, a formal specification is nece ssary. However, there is no formal representation model for PDM system. Theref ore a graphical representation model is constructed to express the various scena rios of interactions between users and the PDM system. Statechart is then used to model the operations of PDM system, Fig.1. Statechart model bridges the curr ent gap between requirements, scenarios, and the initial design specifications o f PDM system. After properly analyzing the PDM system, a new distributed PDM (DPDM) system is proposed. Both graphical representation and statechart models are constructed f or the new DPDM system, Fig.2. New product data of DPDM and new system function s are then investigated to support product information flow in the new distribut ed environment. It is found that statecharts allow formal representations to capture the informa tion and control flows of both PDM and DPDM. In particular, statechart offers a dditional expressive power, when compared to conventional state transition diagr am, in terms of hierarchy, concurrency, history, and timing for DPDM behavioral modeling. 展开更多
关键词 DPDM Statecharts for Distributed product data Management System modelling
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Establishment of Person and Enterprise Process Model in Product Data Management System
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作者 Ming-lun Fang Jun-bo Mao Tao Yu 《Advances in Manufacturing》 2000年第3期239-242,共4页
Before the implementation of product data management (PDM) system, person model and enterprise process model (EPM) must be firstly established. For the convenience of project management, all the related users must be ... Before the implementation of product data management (PDM) system, person model and enterprise process model (EPM) must be firstly established. For the convenience of project management, all the related users must be allocated to the “Person User Role Group” net. Based on the person model and the direction of information flow, the EPM is established subsequently. The EPM consists of several release levels, in which the access controls are defined. The EPM procedure shows the blueprint of the workflow process structure. The establishment of person model and EPM in an enterprise has been instanced at the end of this paper. 展开更多
关键词 product data management(PDM) person model enterprise process model
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Research on Digital Product Modeling Key Technologies of Digital Manufacturing
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作者 DING Gnoping ZHOU Zude +1 位作者 HU Yefa ZHAO Liang 《武汉理工大学学报》 CAS CSCD 北大核心 2006年第S2期646-650,共5页
With the globalization and diversification of the market and the rapid development of Information Technology(IT)and Artificial Intelligence(AI),the digital revolution of manufacturing is coming.One of the key technolo... With the globalization and diversification of the market and the rapid development of Information Technology(IT)and Artificial Intelligence(AI),the digital revolution of manufacturing is coming.One of the key technologies in digital manufacturing is product digital modeling.This paper firstly analyzes the information and features of the product digital model during each stage in the product whole lifecycle,then researches on the three critical technologies of digital modeling in digital man-ufacturing-product modeling,standard for the exchange of product model data and digital product data management.And the potential signification of the product digital model during the process of digital manufacturing is concluded-product digital model integrates primary features of each stage during the product whole lifecycle based on graphic features,applies STEP as data ex-change mechanism,and establishes PDM system to manage the large amount,complicated and dynamic product data to implement the product digital model data exchange,sharing and integration. 展开更多
关键词 digital manufacturing digital product modeling standard for the exchange of product model data(STEP) product data management(PDM)
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An Open Architecture and Implementation for Product Data Management
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作者 张新访 《High Technology Letters》 EI CAS 1995年第2期1-6,共6页
In this paper, an open architecture and its implementation for product data management are presented. The system architecture, product data definition model, and a set of components of the architecture are discussed i... In this paper, an open architecture and its implementation for product data management are presented. The system architecture, product data definition model, and a set of components of the architecture are discussed in detail. Especially, the principle and some mechanism of one of the components, an object oriented database management system GH-EODB, are discussed in more detail. The architecture is extensible and adaptable. 展开更多
关键词 product data MANAGEMENT PDES/STEP OBJECT ORIENTED dataBASE product model
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水驱油藏智能注采技术研究与应用
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作者 秦洪岩 《河北石油职业技术大学学报》 2026年第1期40-42,48,共4页
为了解决注水开发油藏测调成功率和数智化程度低、实时录取资料的生产难题,改善油层纵向动用程度,提高平面波及体积,研发了应用智能注采联动系统,充分利用了智能分层注水和智能分层采油两套技术,形成平面一一对应,纵向分隔清晰,资料录... 为了解决注水开发油藏测调成功率和数智化程度低、实时录取资料的生产难题,改善油层纵向动用程度,提高平面波及体积,研发了应用智能注采联动系统,充分利用了智能分层注水和智能分层采油两套技术,形成平面一一对应,纵向分隔清晰,资料录取完善,调控便捷有序的优选智能注采联动开发方式。通过注采联动,实时监控智能分层注水和智能分层采油情况,对各层系注水量、产液量、含水率、压力等情况进行动态对比分析;通过大数据建模的方式深入认识油水井间层位连通关系;统筹考虑注采井组注入、采出端,强化井组调层产油与分层注水措施,实现“智能注采一体化”。提高油藏调控的针对性与灵活性,提高注水方案执行率。 展开更多
关键词 注水油藏 实时调控 智能注采 数据建模
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新质生产力培育对饲料企业投资决策的影响
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作者 刘奎汝 《中国饲料》 北大核心 2026年第2期105-108,共4页
文章立足饲料行业全产业链特性,运用产业经济理论与面板数据模型,剖析新质生产力培育对饲料企业投资决策的作用路径与影响效应。选取2020—2024年中国30家重点饲料企业数据,从投资方向、规模、风险构建3个维度分析框架。结果显示,新质... 文章立足饲料行业全产业链特性,运用产业经济理论与面板数据模型,剖析新质生产力培育对饲料企业投资决策的作用路径与影响效应。选取2020—2024年中国30家重点饲料企业数据,从投资方向、规模、风险构建3个维度分析框架。结果显示,新质生产力培育显著推动饲料企业向生物饲料研发、智能化生产、绿色供应链领域倾斜投资;针对新质生产力培育对饲料企业投资决策产生的核心影响,政策环保要求与养殖端需求变化具有正向调节作用。研究结果为饲料企业优化投资结构、农业领域新质生产力落地提供理论支撑与行业参考。 展开更多
关键词 新质生产力 饲料企业 投资决策 面板数据模型 绿色转型
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基于PanelData的金砖国家对美高技术产品出口竞争力及影响因素分析 被引量:3
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作者 孙莹 李苗 何维达 《情报杂志》 CSSCI 北大核心 2012年第12期22-27,共6页
以巴西、俄罗斯、印度、中国、南非组成的金砖国家(BRICS),作为新兴经济代表,纷纷重视高技术产品的出口竞争。2010年金砖国家高技术产品出口总值达5008亿美元,占世界高技术产品出口的22.76%,而金砖国家在美国市场高技术产品的出口竞争... 以巴西、俄罗斯、印度、中国、南非组成的金砖国家(BRICS),作为新兴经济代表,纷纷重视高技术产品的出口竞争。2010年金砖国家高技术产品出口总值达5008亿美元,占世界高技术产品出口的22.76%,而金砖国家在美国市场高技术产品的出口竞争成为新的焦点。本文旨在比较金砖国家对美高技术产品出口竞争力影响因素,挖掘金砖国家高技术产品出口的竞争优势,并借鉴金砖国家的成功经验,为中国提出对策建议,以增强中国对美高技术产品出口竞争力。 展开更多
关键词 金砖国家 高技术产品 出口竞争力 PANEL data 变系数模型
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双源数据驱动下基于“问题-建议”的产品创新机会识别
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作者 郭艳丽 高蕊 +1 位作者 邹美凤 刘紫丹 《农业图书情报学报》 2026年第4期47-60,共14页
[目的/意义]利用在线评论数据,提出一种以“问题-建议”为导向的产品创新机会识别方法,开展产品创新机会识别研究,可以帮助企业高效利用用户资源开展产品创新工作。[方法/过程]进行普通用户和领先用户评论数据的收集和预处理;进而利用B... [目的/意义]利用在线评论数据,提出一种以“问题-建议”为导向的产品创新机会识别方法,开展产品创新机会识别研究,可以帮助企业高效利用用户资源开展产品创新工作。[方法/过程]进行普通用户和领先用户评论数据的收集和预处理;进而利用BERT预训练模型和LDA主题模型进行情感分类和主题聚类,挖掘普通用户问题和领先用户建议;基于语义相似度分析,实现“问题-建议”主题映射,最终识别具有较高创新价值的产品创新机会。[结果/结论]以运动相机为案例分析对象,验证该产品创新机会识别方法的可行性。结果表明,本研究所提研究框架可以准确发现产品创新机会,帮助企业挖掘产品创新潜力,做出具有竞争力的产品研发决策。 展开更多
关键词 双源数据 自然语言处理 BERT模型 LDA主题模型 产品创新机会识别
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Sum-Product Networks模型的研究及其在文本分类的应用 被引量:2
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作者 李俊 《电子设计工程》 2016年第24期42-45,共4页
图模型在机器学习有着广泛的应用。相比图模型,Sum-Product Networks模型具有更强表达能力和更快的推理速度,所以其在对文本和图像数据建模有着广泛的应用。本文总结Sum-Product Networks这一新的深度概率模型的研究进展,先介绍了固定... 图模型在机器学习有着广泛的应用。相比图模型,Sum-Product Networks模型具有更强表达能力和更快的推理速度,所以其在对文本和图像数据建模有着广泛的应用。本文总结Sum-Product Networks这一新的深度概率模型的研究进展,先介绍了固定结构的Sum-Product Networks的参数学习方法,再介绍了根据不同的输入数据而进行的结构和参数学习方法。并且介绍了判别式和生成模型的Sum-Product Networks,最后介绍了Sum-Product Networks在文本分类上的应用。 展开更多
关键词 Sum-product Networks模型 概率模型 数据挖掘算法 文本分类
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基于大语言模型的遥感信息产品智能分析系统
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作者 廖远鸿 林鸣 白玉琪 《自然资源遥感》 北大核心 2026年第1期10-18,共9页
随着遥感科学技术的迅速发展,遥感信息产品数据呈现出海量化与多样化的特征。现有平台虽具备基础数据服务和信息处理能力,但在自动化知识提取和专业化问答服务方面仍存在局限,难以智能解析用户需求并动态生成适应性的分析流程。针对这... 随着遥感科学技术的迅速发展,遥感信息产品数据呈现出海量化与多样化的特征。现有平台虽具备基础数据服务和信息处理能力,但在自动化知识提取和专业化问答服务方面仍存在局限,难以智能解析用户需求并动态生成适应性的分析流程。针对这一问题,该文提出并构建了一个基于大语言模型的遥感信息智能分析框架,并以地表覆盖制图为实验场景进行验证。该框架运用自然语言解析和提示工程技术,自动完成时空映射、核心变量构建和指标生成,并调用开放数据立方体进行高效的数据管理与计算。实验结果表明,该系统在综合遥感数据分析能力上超越了单纯依赖生成式预训练变换器(generative pre-trained Transformer,GPT)生成的结果,显著提升了知识服务的准确性和专业性,有望推动遥感信息产品的智能知识服务发展。 展开更多
关键词 地理信息知识服务 遥感信息产品 大语言模型 开放数据立方体
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MES一键智控数据模型研究
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作者 叶昱冬 高飞 《计算机应用与软件》 北大核心 2026年第2期127-133,153,共8页
为了提升效率、降低操作难度,提出基于制造执行系统(Manufacturing Execution System,MES)的一键智控生产方式。该生产方式对传统生产流程进行细粒度的解构,并运用知识图谱的方法对解构的生产工步进行重构。以饮料前处理生产为例,将企... 为了提升效率、降低操作难度,提出基于制造执行系统(Manufacturing Execution System,MES)的一键智控生产方式。该生产方式对传统生产流程进行细粒度的解构,并运用知识图谱的方法对解构的生产工步进行重构。以饮料前处理生产为例,将企业订单数据、配方数据、工单数据、工步数据、生产资源数据、指令数据、实做数据进行建模,形成企业生产的MES智控大脑。通过具体项目实践,该项技术可以有效提升产品生产效率、降低人为出错概率。 展开更多
关键词 数据模型 一键智控 制造执行系统 饮料生产
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边缘计算环境下的生产数据预测方法
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作者 李硕成 《移动信息》 2026年第3期250-252,273,共4页
随着智能制造领域的快速发展,生产现场对数据预测的实时性与准确性要求日益提高。针对传统云计算架构在工业生产场景中存在的高延迟、带宽占用大和离线不可用等问题,文中提出了一种基于边缘计算环境的生产数据预测方法。该方法通过边缘... 随着智能制造领域的快速发展,生产现场对数据预测的实时性与准确性要求日益提高。针对传统云计算架构在工业生产场景中存在的高延迟、带宽占用大和离线不可用等问题,文中提出了一种基于边缘计算环境的生产数据预测方法。该方法通过边缘节点部署轻量化时序预测模型,结合增量学习机制实现就近计算与模型自适应。实验表明,所提方法突破了边缘设备算力约束下的高精度预测难题,为生产现场智能决策提供了可靠技术方案。 展开更多
关键词 边缘计算 生产数据预测 时序分析 轻量化模型
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Research on Product Information Integrating and Sharing for Dynamic Colla boration 被引量:4
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作者 HE Wen-rui, QIN Zhong-bao, Qin Ji-feng, HE Wei-ping (Education Ministry Key Laboratory of Contemporary Design and Integrate d Manufacturing Technology, Northwestern Polytechnical University, Xi’an 710072, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期163-164,共2页
Dynamic Collaboration emerges as the new trend of n et working and collaborating work in manufacturing industry, in which product infor mation sharing among allied enterprises plays very important roles in collaborat ... Dynamic Collaboration emerges as the new trend of n et working and collaborating work in manufacturing industry, in which product infor mation sharing among allied enterprises plays very important roles in collaborat ing product development. This thesis aims at studying the integrating, contr olling and sharing mode of product information among the heterogeneous and dispe rsed environments through Internet, and proposes the information integrating/sha ring architecture based on the Product Master Model (PMM). The following are the main contents of this thesis: 1) Research on the XML based PMM model for integration and sharing of product in formation After analyzing the requirement of the allied Enterprise for the product infor mation, the XML based product master model (XPMM) is proposed as the integrating mechanism of heterogeneous and dispersed product information. The XPMM is divid ed into some sub-models: whole-life controlling model, product defining model, conception model, design model, product structure model, machining model, q uality model, evaluating model. The character and accessing approach of XPMM is discussed in detail. 2) Research on the mapping pattern and mapping rule of STEP/XML According to feature of XML Schema and STEP EXPRESS, the memory-constructing-t ree model is put forward as STEP/XML mapping pattern, which is constructed dynam ically according to the bottom-to-top reference relationship. Based on mapping pattern, the multi-layer XML/STEP mapping rule is discussed detailed including relation mapping, entity mapping, data type mapping, reference mapping and func tion mapping. 3) Research on the Product Information Integration and Sharing (PIIS) Architectu re Based on the XPMM, the PIIS architecture is proposed. The PIIS support the local and dispersed product information to be integrated and shared on the contro l of the XPMM. The architecture is divided into three layers :Applying-Obj ect-LayerData-Integration-Layer and STEP-Data-Layer. The kernel of the PI IS Architecture is this Data-Integration-Layer, which control the whole proces s of XPMM creating, the data approaching. The function and structure of every la yer is discussed too. 展开更多
关键词 XML STEP product master model data integrati ng
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XML-based Data Processing in Network Supported Collaborative Design 被引量:2
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作者 Qi Wang Zhong-Wei Ren Zhong-Feng Guo 《International Journal of Automation and computing》 EI 2010年第3期330-335,共6页
In the course of network supported collaborative design,the data processing plays a very vital role.Much effort has been spent in this area,and many kinds of approaches have been proposed.Based on the correlative mate... In the course of network supported collaborative design,the data processing plays a very vital role.Much effort has been spent in this area,and many kinds of approaches have been proposed.Based on the correlative materials,this paper presents extensible markup language(XML)based strategy for several important problems of data processing in network supported collaborative design,such as the representation of standard for the exchange of product model data(STEP)with XML in the product information expression and the management of XML documents using relational database.The paper gives a detailed exposition on how to clarify the mapping between XML structure and the relationship database structure and how XML-QL queries can be translated into structured query language(SQL)queries.Finally,the structure of data processing system based on XML is presented. 展开更多
关键词 Extensible markup language(XML) network supported collaborative design standard for the exchange of product model data(STEP)data analysis data processing relational database
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STEP AP 242 Managed Model-based 3D Engineering:An Application Towards the Automation of Fixture Planning 被引量:2
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作者 Remil George Thomas Deepak Lawrence K. Manu R. 《International Journal of Automation and computing》 EI CSCD 2021年第5期731-746,共16页
Fixture design and planning is one of the most important manufacturing activities, playing a pivotal role in deciding the lead time for product development. Fixture design, which affects the part-quality in terms of g... Fixture design and planning is one of the most important manufacturing activities, playing a pivotal role in deciding the lead time for product development. Fixture design, which affects the part-quality in terms of geometric accuracy and surface finish, can be enhanced by using the product manufacturing information(PMI) stored in the neutral standard for the exchange of product model data(STEP) file, thereby integrating design and manufacturing. The present paper proposes a unique fixture design approach, to extract the geometry information from STEP application protocol(AP) 242 files of computer aided design(CAD) models, for providing automatic suggestions of locator positions and clamping surfaces. Automatic feature extraction software "FiXplan", developed using the programming language C#, is used to extract the part feature, dimension and geometry information. The information from the STEP AP 242 file is deduced using geometric reasoning techniques, which in turn is utilized for fixture planning. The developed software is observed to be adept in identifying the primary, secondary, and tertiary locating faces and locator position configurations of prismatic components. Structural analysis of the prismatic part under different locator positions was performed using commercial finite element method software, ABAQUS, and the optimized locator position was identified on the basis of minimum deformation of the workpiece.The area-ratio(base locator enclosed area(%)/work piece base area(%)) for the ideal locator configuration was observed as 33%. Experiments were conducted on a prismatic workpiece using a specially designed fixture, for different locator configurations. The surface roughness and waviness of the machined surfaces were analysed using an Alicona non-contact optical profilometer. The best surface characteristics were obtained for the surface machined under the ideal locator positions having an area-ratio of 33%, thus validating the predicted numerical results. The efficiency, capability and applicability of the developed software is demonstrated for the finishing operation of a sensor cover – a typical prismatic component having applications in the naval industry, under different locator configurations.The best results were obtained under the proposed ideal locator configuration of area-ratio 33%. 展开更多
关键词 Standard for the exchange of product model data(STEP)application protocol(AP)242 product manufacturing information computer-aided fixture design computer aided design(CAD)/computer aided manufacturing(CAM) AUTOMATION computer integrated manufacturing 3D surface roughness
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智能油藏工程的理论演进、技术体系及发展方向
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作者 廉培庆 马翠玉 《世界石油工业》 2026年第1期212-221,共10页
为了系统梳理油藏工程从经验分析、机理建模、数值模拟到智能驱动的演进脉络,并明确智能油藏工程的关键技术进展、核心挑战与未来趋势,采用了文献综述与体系归纳方法,以油藏工程发展阶段为背景,系统分析机器学习、深度学习、强化学习及... 为了系统梳理油藏工程从经验分析、机理建模、数值模拟到智能驱动的演进脉络,并明确智能油藏工程的关键技术进展、核心挑战与未来趋势,采用了文献综述与体系归纳方法,以油藏工程发展阶段为背景,系统分析机器学习、深度学习、强化学习及物理信息神经网络等技术在生产动态分析、流体参数预测、代理模型构建、生产优化与提高油气采收率等关键环节的应用现状,并深入探讨智能方法与传统数值模拟方法之间的衔接互补关系。研究结果表明:①智能时序预测方法(如LSTM、GRU)能够有效刻画多井注采耦合信号的动态特征,在非常规油藏和高含水期油田的产量预测中优于传统递减曲线方法,并借助迁移学习实现跨油藏模型快速应用;②数据-物理融合建模方法将状态方程、相平衡条件等物理约束显式嵌入神经网络训练过程,显著提升了流体参数预测的物理一致性与外推能力,形成了从经验回归到机理引导的智能预测新范式;③以物理信息神经网络(PINNs)为代表的智能代理模型通过将控制方程残差作为损失函数组成部分,在实现数值模拟数量级加速的同时,增强了历史拟合与参数反演的物理可信度,推动了油藏模拟从定期更新向实时演化转型;④强化学习与多目标优化算法能够在高维约束空间中实现注采参数与井网部署的自主决策与动态调整,形成从静态优化转向动态协同的智能生产调控体系,并为提高油气采收率技术的智能筛选与组合优化提供支撑。结论认为,智能油藏工程正推动油藏开发由单一物理驱动向数据-物理-智能深度融合的新范式演进,其未来发展需构建统一的大数据治理框架以夯实数据基础,并在智能模型中系统引入物理约束与工程规则,从而形成可解释、可迁移、可闭环的智能决策系统,为油气行业新质生产力构建提供关键技术支撑。 展开更多
关键词 油藏工程 智能驱动 数据-物理融合 生产动态预测 代理建模 生产优化 提高采收率 数字孪生
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基于Panel Data的中国农业发展因素的实证分析 被引量:2
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作者 赵雪芳 李亚琼 《数理统计与管理》 CSSCI 北大核心 2009年第1期128-134,共7页
本文利用1998-2004年我国29个省的面板数据,将农业生产的投入要素区分为物质性投入要素和非物质性投入要素,分别建立了中性技术和非中性技术条件下的C-D生产函数和扩展的C-D生产函数模型,对影响我国农业发展的因素进行了实证分析,并依... 本文利用1998-2004年我国29个省的面板数据,将农业生产的投入要素区分为物质性投入要素和非物质性投入要素,分别建立了中性技术和非中性技术条件下的C-D生产函数和扩展的C-D生产函数模型,对影响我国农业发展的因素进行了实证分析,并依据分析结果,对促进我国农业发展提出了政策建议. 展开更多
关键词 面板数据 中性技术和非中性技术 C—D生产函数 随机效用模型
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数字普惠金融对江苏制造业企业全要素生产率的影响研究
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作者 陈永杰 王玮 +3 位作者 侯欢鑫 高星桐 夏天乐 李品 《煤炭经济研究》 2026年第2期113-121,共9页
在数字技术与金融深度融合的背景下,数字普惠金融作为金融与科技结合的产物,正成为推动实体经济高质量发展的重要力量。以江苏省制造业企业为研究对象,采用北京大学数字普惠金融指数和数据包络分析(DEA)模型,分别对江苏数字普惠金融发... 在数字技术与金融深度融合的背景下,数字普惠金融作为金融与科技结合的产物,正成为推动实体经济高质量发展的重要力量。以江苏省制造业企业为研究对象,采用北京大学数字普惠金融指数和数据包络分析(DEA)模型,分别对江苏数字普惠金融发展现状和制造业企业全要素生产率现状进行了测算和分析。在此基础上,构建双重差分(DID)模型,实证检验了数字普惠金融对制造业企业全要素生产率的影响,并进行了稳健性检验和异质性分析。最后,剖析了江苏制造业企业数字普惠金融赋能效果不足的原因,并提出了相应的政策建议。数字普惠金融对江苏制造业企业全要素生产率存在显著的正向影响。融资约束、资产负债率与全要素生产率显著负相关,净资产收益率、现金流量比率、股东持股集中度与全要素生产率显著正相关。数字普惠金融对苏南地区制造业企业全要素生产率的促进作用最为显著,苏中地区次之,苏北地区相对较低。 展开更多
关键词 数字普惠金融 制造业企业 全要素生产率(TFP) 数据包络分析(DEA) 双重差分(DID)模型
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Research on the Component-Centered Version Model in the PDM System 被引量:2
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作者 FANG Yong-ze ZHONG Yi-fang 《Computer Aided Drafting,Design and Manufacturing》 2006年第1期50-56,共7页
A version of a product consists of the product structure tree and the versions of all its components. The model includes two sets of data: attributes and documents describing each component. The paper discusses the v... A version of a product consists of the product structure tree and the versions of all its components. The model includes two sets of data: attributes and documents describing each component. The paper discusses the version change relations between a sub-node component and a up-node component in a product structure tree, analyzes the version control system for a static reference and that for a dynamic reference and proposes a product structure model in support of dynamic reference, which is easy to use and contains a complete set of information providing an essential way of data organization for the PDM system. 展开更多
关键词 computer application version model product data management versioncontrol static reference dynamic reference
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