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21.
俄罗斯的一些水泥厂以最少的投入进行技改,旨在提高其生产效率。借助现代选粉技术改造水泥粉 磨系统,并给现有的篦式冷却机装备静止的入口段,可以低的投资,快速获取投资回报。 相似文献
22.
针对南钢历年来在高炉煤气洗涤水污泥脱水处理中遇到的压滤机的问题,指出了单隔膜压滤机的缺陷,并在充分词研和实际应用的基础上改用厢式双隔膜高效板框压滤机,取得了较好的效果。 相似文献
23.
根据啮合型同向旋转双螺杆挤出非充满熔融的理论模型,对描述非充满熔融过程的主要物理量:固相高度变化函数、熔融速率及熔融区总长等进行了计算分析,并对有关影响因素进行了讨论。 相似文献
24.
25.
智慧水利解析 总被引:4,自引:1,他引:3
智慧水利是水利高质量发展的显著标志,是运用大数据、人工智能、物联网、云计算、移动互联等新一代信息通信技术,基于自然水系、水利工程体系和水利管理体系,智慧地将适量适质的水适时送到适地,为实现长久水安澜、优质水资源、宜居水环境、健康水生态提供支撑。智慧水利包括目标、对象、时空、技术、价值、成效等六个维度的内涵。目标维度包括问题识别与目标制订,对象维度包括服务主体与水利业务,时空维度包括监控环节与决策过程,技术维度包括赋能体系与核心技术,价值维度包括概念模型与推进路径,成效维度包括功能表征与建设愿景。在智慧水利建设中,数据是基础,要高度重视水利数据的收集、开放和共享;信息是关键,要高度重视监测数据的信息提取和分析;知识是核心,要加强水利知识的挖掘、提升和知识的积累;智能和智慧是目的,要重视人工智能的使用和标准化管理体系的构建。 相似文献
26.
Cyber-physical production systems enable adaptivity and flexibility when manufacturing customized products in small batches. Due to varying routes and a high variance of workpieces, material flows in cyber-physical production systems can get highly complex, which can lead to physically induced disturbances that can result in accidents or decreased throughput and high costs. This issue can be addressed by applying a physics engine to simulate the physical interaction between workpieces and the material handling systems during the operation. Connecting such a digital model to a real material handling system in order to derive simulation-based decision support leads to the concept of digital twins. To date, few practical implementations of digital twins in manufacturing outside the machine tool domain were reported. Therefore, this paper describes the modeling and the subsequent implementation of an integrated system that consists of a real material handling system and its digital twin, based on physics simulation. A practical use case demonstrates the versatile advantages of the implemented solution for a manufacturing system with respect to the three digital twin functions prediction, monitoring and diagnosis. 相似文献
27.
Computer Numerical Control Machine Tool (CNCMT) Digital Twin (DT) model is a carrier for complex, time-varying, coupled data of CNCMT, which can theoretically provide a time-varying high-fidelity model. However, there are still many difficulties in its implementation process. And the key issue is how to realize the updated DT model with performance attenuation and validate it. In order to solve this problem, a model consistency retention method for CNCMT DT model is studied and proposed in this paper. Firstly, the framework of consistency retention method for DT model is designed including both digital space and physical space. The principles of data management and performance attenuation update in digital space are elaborated. Then, the implementation method for consistency retention of CNCMT DT model is studied in terms of performance attenuation update workflow for wear and other damage separately. Finally, a case study for the establishment and application of high-fidelity test bench DT model that focusing on rolling guide-rail is carried out to show the implementation flow of the proposed method and verify its operability and effectiveness. 相似文献
28.
Various kinds of engineering software and digitalized equipment are widely applied through the lifecycle of industrial products. As a result, massive data of different types are being produced. However, these data are hysteretic and isolated from each other, leading to low efficiency and low utilization of these valuable data. Simulation based on theoretical and static model has been a conventional and powerful tool for the verification, validation, and optimization of a system in its early planning stage, but no attention is paid to the simulation application during system run-time. With the development of new-generation information and digitalization technologies, more data can be collected, and it is time to find a way for the deep application of all these data. As a result, the concept of digital twin has aroused much concern and is developing rapidly. Dispute and discussions around concepts, paradigms, frameworks, applications, and technologies of digital twin are on the rise both in academic and industrial communities. After a complete search of several databases and careful selection according to the proposed criteria, 240 academic publications about digital twin are identified and classified. This paper conducts a comprehensive and in-depth review of these literatures to analyze digital twin from the perspective of concepts, technologies, and industrial applications. Research status, evolution of the concept, key enabling technologies of three aspects, and fifteen kinds of industrial applications in respective lifecycle phase are demonstrated in detail. Based on this, observations and future work recommendations for digital twin research are presented in the form of different lifecycle phases. 相似文献
29.
Digital twin represents a fusion of the informational and physical domains, to bridge the material and virtual worlds. Existing methods of digital twin modeling are mainly based on modular representation, which limits guidance of the modeling process. Such methods do not consider the components or operational rules of the digital twin in detail, thereby preventing designers from applying these methods in their fields. With the increasing application of digital twin to various engineering fields, an effective method of modeling a multi-dimensional digital twin at the conceptual level is required. To such an end, this paper presents a method for the conceptual modeling of a digital twin based on a five-dimensional digital twin framework to represent the complex relationship between digital twin objects and their attributes. The proposed method was used to model the digital twin of an intelligent vehicle at the concept level. 相似文献
30.
Big data is one of the most important resources for the promotion of smart customisation. With access to data from multiple sources, manufacturers can provide on-demand and customised products. However, existing research of smart customisation has focused on data generated from the physical world, not virtual models. As physical data is constrained by what has already occurred, it is limited in the identification of new areas to improve customer satisfaction. A new technology called digital twin aims to achieve this integration of physical and virtual entities. Incorporation of digital twin into the paradigm of existing data-driven smart customisation will make the process more responsive, adaptable and predictive. This paper presents a new framework of data-driven smart customisation augmented by digital twin. The new framework aims to facilitate improved collaboration of all stakeholders in the customisation process. A case study of the elevator industry illustrates the efficacy of the proposed framework. 相似文献