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61.
Venturi scrubbers for filtered venting have been installed in nuclear power plants worldwide. Venturi scrubbers can eliminate fission products from a polluted gas by interaction through gas–liquid interfaces. Therefore, droplet diameter is important from the viewpoint of decontamination. When Venturi scrubbers are used in severe accidents, the gas flow velocity might be extremely high. In these studies, the authors did not measure droplet diameter under extremely high gas velocity conditions. In the scenarios, experimental data pertaining to droplet diameter, under the extremely high gas flow velocity, are required. Therefore, this objective is to evaluate the diameter of extremely high-speed droplets. A visualization experiment was conducted using a Venturi scrubber. The droplet diameter distribution and the Sauter mean diameter (SMD) were determined. By comparing between the experimental value of SMDs and the one evaluated using Nukiyama–Tanasawa equation, it was confirmed that the Nukiyama–Tanasawa equation can be used to evaluate SMD with good accuracy in the gas velocity range of 82–250 m/s, except the highest gas velocity conditions. Furthermore, the droplet generation mechanism in the Venturi scrubber was considered to clarify the main reason why the Nukiyama–Tanasawa equation can be used to evaluate SMD droplet diameter.  相似文献   
62.
使用基于克里金理论的插值计算方法对均匀网格与随机排列等不同分布类型的辐射剂量场进行了数据重构与可视化研究,并将重构结果与常用的反距离加权插值法进行了对比,分析了不同插值方法对辐射剂量场重构精度与可视化显示效果的影响。结果表明:对于多数情况,克里金插值法在辐射剂量场重构的精度与可视化显示的效果上均明显优于反距离加权插值法,算例中克里金插值法的结果与原始数据之间的偏差在10%以内,而反距离加权插值法的结果与原始数据之间的偏差基本在15%以上;但在辐射剂量场梯度变化较大且已知数据极少的区域,克里金插值法的计算结果偏差会增大,此时可使用反距离加权插值作为其补充,综合使用。本文的研究工作,验证了克里金插值法在辐射剂量场重构与可视化方面的应用潜力,可为推动辐射剂量场可视化仿真技术的发展提供技术支持。  相似文献   
63.
The new generation of industrial 4.0 intelligent manufacturing system consists of Human-Cyber-Physical System (HCPS), integrating human with cyber and physical systems. In manufacturing, a digital-twin visualization architecture is to solve the human-machine interaction problem that concerns digital-twin modeling on the Cyber-Physical (C-P) side and on the Human-Cyber side. Although there are many related research and applications, there lacks attention in terms of full life cycle functional services and lightweight architecture. This paper presents a general architecture of digital-twin visualization for flexible manufacturing systems (FMS). How the digital-twin C-P modeling of multi-source heterogeneous information can be described is investigated and how the 3D visualized human-machine interaction with digital-twin scenario information is explored in the proposed architecture. Besides, the visualization method of high-value information, relating to the life cycle planning, design, debugging and service stages, is studied and discussed thoroughly. Also, a digital-twin modeling concept of "Geometric information (G)-Historical samples (H)-Object attribute (O)-Snapshot collection (S)-Topology constraint (T)" (GHOST) is proposed, and methods for developing virtual digital-twin scenes architecture are presented. Based on the proposed modeling concept of GHOST for digital-twin, prototypes have been developed for the general platform of digital-twin RESTful services and the cross-platform general visual mock-up software. Experimental results show that this method is effective in the FMS lifecycle in various aspects.  相似文献   
64.
Large-scale ecosystem management involves consideration of many factors for informed decision making. The EverVIEW Data Viewer is a cross-platform desktop decision support tool to help decision makers compare simulation model outputs from competing plans for restoring Florida's Greater Everglades. The integration of NetCDF metadata conventions into EverVIEW allows end-users from multiple institutions within and beyond the Everglades restoration community to share information and tools. Our development process incorporates continuous interaction with targeted end-users for increased likelihood of adoption. One of EverVIEW's signature features is side-by-side map panels, which can be used to simultaneously compare species or habitat impacts from alternative restoration plans. Other features include examination of potential restoration plan impacts across multiple geographic or tabular displays, and animation through time. As a result of an iterative, standards-driven approach, EverVIEW is relevant to large-scale planning beyond Florida, and is used in multiple biological planning efforts in the United States.  相似文献   
65.
Ink drops have to be filled into the square cells for an electrowetting display panel. Several ink solutions such as dodecane, tetradecane, and hexadecane were used as test liquids. These fluids have viscosities less than 4 mPas and surface tensions between 23.3 and 26 mN/m and contact angles less than 50°. A slot coating die was employed to deliver these liquids to fill up the square cells. The effects of several parameters such as coating thickness and coating speed were examined. Operating windows inside which the stable filling is possible could be found for these liquids. Several defects were observed outside the operating windows. A flow visualization technique was applied to observe the fluid motion in the coating bead region, particularly the movements of upstream and downstream menisci, the mechanism of liquid filling was discussed.  相似文献   
66.
Assessing the time-varying sensitivity of environmental models has become a common approach to understand both the value of different data periods for estimating specific parameters, and as part of a diagnostic analysis of the model structure itself (i.e. whether dominant processes are emerging in the model at the right times and over the appropriate time periods). It is not straightforward to visualize these results though, given that the window size over which the time-varying sensitivity is best integrated generally varies for different parameters. In this short communication we present a new approach to visualizing such time-varying sensitivity across time scales of integration. As a case study, we estimate first order sensitivity indices with the FAST (Fourier Amplitude Sensitivity Test) method for a typical conceptual rainfall–runoff model. The resulting plots can guide data selection for model calibration, support diagnostic model evaluation and help to define the timing and length of spot gauging campaigns in places where long-term calibration data are not yet available.  相似文献   
67.
为了清楚的在全局范围内展开比例积分(PI)的设计参数与设计效果的因果关系,提出一种基于LCL型单相并网逆变器的PI数据可视化设计。根据系统的稳定性、系统频域和时域的性能指标,利用Matlab得出最优PI参数的可视化数据区域,此设计方法简单、快速,无需反复试凑。在实验室设计一台3 kW的原理样机验证该理论的正确性。实验结果表明,基于数据可视化设计的PI参数,单相LCL型电流并网系统具有良好的跟踪特性和抗干扰特性,实现高的功率因数并网,系统具有良好的动静态性能。  相似文献   
68.
Today’s large scale availability of data from industrial plants is an invaluable resource to monitor industrial processes. Data-based methods can lead to better understanding, optimization or detection of anomalies. As a particular case, batch processes have attracted special interest due to their widespread presence in the industry. The aim of monitoring, in this case, is to compare different runs or implementations of a process with the baseline or normal operating one. On the other hand, visual exploration tools for process monitoring have been a prolific application field for self-organizing maps (SOM). In this paper, we exploit data-based models, obtained by means of SOM, for the visual comparison of industrial processes. For that purpose, we propose a method that defines a new visual exploration tool, called dissimilarity map. We also expose the need to consider dynamic information for effective comparison. The method is assessed in two industrial pilot plants that implement the same process. The results are discussed.  相似文献   
69.
Massive sequence view (MSV) is a classic timeline-based dynamic network visualization approach. However, it is vulnerable to visual clutter caused by overlapping edges, thereby leading to unexpected misunderstanding of time-varying trends of network communications. This study presents a new edge sampling algorithm called edge-based multi-class blue noise (E-MCBN) to reduce visual clutter in MSV. Our main idea is inspired by the multi-class blue noise (MCBN) sampling algorithm, commonly used in multi-class scatterplot decluttering. First, we take a node pair as an edge class, which can be regarded as an analogy to classes in multi-class scatterplots. Second, we propose two indicators, namely, class overlap and inter-class conflict degrees, to measure the overlapping degree and mutual exclusion, respectively, between edge classes. These indicators help construct the foundation of migrating the MCBN sampling from multi-class scatterplots to dynamic network samplings. Finally, we propose three strategies to accelerate MCBN sampling and a partitioning strategy to preserve local high-density edges in the MSV. The result shows that our approach can effectively reduce visual clutters and improve the readability of MSV. Moreover, our approach can also overcome the disadvantages of the MCBN sampling (i.e., long-running and failure to preserve local high-density communication areas in MSV). This study is the first that introduces MCBN sampling into a dynamic network sampling.  相似文献   
70.
根据热处理工艺的生产特点,按照数据存储的要求将热处理工艺数据化。同时利用数据库存取访问技术对生产过程记录和过程参数进行实时跟踪记录和存储,并利用互联网技术实现生产全过程的可视化和移动终端的浏览访问,从而实现热处理生产过程的信息化。自动采集、存储和访问,为热处理的智能化生产提供了良好的解决方案。  相似文献   
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