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Uncertainty Evaluation of Automatic Monitoring System for Fine Particulate Matter in Ambient Air
Yang Shuo,
Pan Zhi Qiang,
Wang Dou Wen
Issue:
Volume 9, Issue 6, December 2021
Pages:
85-89
Received:
26 February 2021
Accepted:
12 March 2021
Published:
29 November 2021
Abstract: Ambient air fine particulate matter (PM2.5) is a kind of instantaneous variation of space and time that cannot be repeated. In the process of fluid sampling analysis of real-time data, there are too many variables and too fast component changes for the laboratory to undertake such tests. The fast automatic monitoring technology provides real-time measurement consistency and reliability, which is comparable in terms of cost effectiveness technical process optimization and life cycle. In this case, suitable reference gas for PM2.5 (mg/m3) could not be found, so β ray or oscillating balance method (X method) and manual weighing method (Y method, as the primary test method) were respectively used. Moreover, related to the sampling frequency of tolerance limit, discussion is given on the detection power (1-β) for the difference (∆) between the X and Y, for their acceptance probabilistic risk characteristics of operational curve based on the trade-off, and on sample sizes (n) under α and β risks, as well as the acceptable level of the cost of wrong decision. This paper belongs to the research category of unstable samples analysis, and involves the evaluation of two components, ur, rel(range) and uR, rel(bat). The assessment is based on the overall concept of top-down. All cumulative effects are incorporated into the continuous and closed system as far as possible. Under the premise of ensuring that the acceptable level is under statistical control, reasonable estimates of quality objectives and uncertainties are obtained.
Abstract: Ambient air fine particulate matter (PM2.5) is a kind of instantaneous variation of space and time that cannot be repeated. In the process of fluid sampling analysis of real-time data, there are too many variables and too fast component changes for the laboratory to undertake such tests. The fast automatic monitoring technology provides real-time m...
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Real-time Simulation Methods for Robots with a Flexible Arm Based on Computer Graphics Technology
Hiroshi Seki,
Katsunori Ueno,
Katsuhiko Hirano
Issue:
Volume 9, Issue 6, December 2021
Pages:
90-97
Received:
26 October 2021
Accepted:
23 November 2021
Published:
2 December 2021
Abstract: A robot with a flexible arm that is controlled with a remotely operated water-pressure mechanism has been developed for dismantling objects that are heavily contaminated by radioactive materials during decommissioning of nuclear power plants. The objective of this research is to develop a process planning support system and method that can improve the accuracy of estimating the time required by the robot to complete its dismantling activity, support recovery from delays, and determine the feasibility of conducting a dismantling process in the reactor building. Since the flexible arm has a more complex mechanism and shapes those that of multi-axis robots, unique movable arm structures were modeled with a tool for three-dimensional (3D) computer graphics (CG) technology. The 3D CG model was used to make valid operation sequences for planning the motion of the robot. With the help of a prototype system, motion planning can perform to calculate the duration needed for the robot to complete its operation. The calculated duration is then used for updating the planned duration of a specific activity in a dismantling schedule. To plan the robot behaviors for complex dismantling processes, a simplified planning method with few virtual controllers based on a spline inverse kinematics (IK) with a non-uniform rational B-spline (NURBS) curve for an arm comprised of pistons and cylinders pressurized by water was studied. A prototype system for planning the behaviors of the robot was evaluated, and it was confirmed that the movement trajectory of the robot and the three-dimensional isometric display could be visualized using the mesh model generated from point-cloud data used to make the environment model of the robot. It was also confirmed that the operations involved in a specific activity of the robot could be completed within the duration determined in the simulation.
Abstract: A robot with a flexible arm that is controlled with a remotely operated water-pressure mechanism has been developed for dismantling objects that are heavily contaminated by radioactive materials during decommissioning of nuclear power plants. The objective of this research is to develop a process planning support system and method that can improve ...
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Effective Folding Line Processing with a Press Method in Origami Forming Using a Low-cost and Simple V-shaped Punch Tool System
Kosuke Terada,
Ichiro Hagiwara
Issue:
Volume 9, Issue 6, December 2021
Pages:
98-112
Received:
25 November 2021
Accepted:
10 December 2021
Published:
24 December 2021
Abstract: Bent products have recently been applied widely in various structures. The method of sharp bending has the advantage of producing bent products with a fine appearance. Meanwhile, it has been recently shown that origami forming can be applied as a free manufacturing method that creates a fine appearance using complex folding lines. Sharp bending and origami forming both require folding lines. Folding lines are produced to make a V-groove before bending. Cutting V-grooves for folding lines requires machining center plants and long working times, which are not suitable for mass production. This paper presents newly developed and convenient V-shaped punch tools for folding line processing in sharp bending and origami forming. As a result, origami forming is expected to be adopted as a press method using V-shaped punch tools. Additionally, this paper reports on the findings of deformation behavior and mechanism obtained in experiments on folding line processing. The investigation for three-dimensional plate deformation around the V-shaped punch terminal shows extended folding line by terminal effect. Phenomena and the required load of V-shape punch indentation are considered in determining the mechanism of V-shape punch indentation from the results of finite element analyses and experiments on groove formation using V-shaped punch tool system.
Abstract: Bent products have recently been applied widely in various structures. The method of sharp bending has the advantage of producing bent products with a fine appearance. Meanwhile, it has been recently shown that origami forming can be applied as a free manufacturing method that creates a fine appearance using complex folding lines. Sharp bending and...
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Dynamical Investigation of Cam-Follower Profile Under Space - 100 to + 120°C Temperature Condition
Jafar Keighobadi,
Hojjat Fouladi,
Davood Hashempour,
Amirreza Rafat Talebi
Issue:
Volume 9, Issue 6, December 2021
Pages:
113-131
Received:
7 November 2021
Accepted:
14 December 2021
Published:
24 December 2021
Abstract: Cam-follower mechanism efficiency in production of desired motions has been proved along the history of space missions. In this paper, according to pre-specified spatial condition of wide temperature variations between -100 and +120 Celsius degrees, some new and innovative cam-follower profile designs are presented. In the first follower mechanism, through rotating a connected screw to a servomotor, changes in length of the moving follower on cam is compensated with respect to the temperature changes of certain spatial conditions. In the second design, an inclined surface cam is equipped with an active controllable follower. As the third suggestion, the design with an inclined cam surface is optimized by investigating the length of the shaft connected to the cam. In the fourth model, a new design is proposed by changing the shaft's material from aluminum to titanium and a modified design is presented. The proposed designs are investigated and compared using the analytical solutions and optimization tools using MATLAB and ANSYS. The purpose of this study was to identify the effect of profile type on the dynamic behavior of the mechanism under the effects of a temperature difference of -100 to +120°C in space condition. It is concluded that changing the length of the follower, using an inclined cam surface and optimizing the length of the shaft connected to the follower are all effective solutions to the cam's volume variation problem. The results also indicate that for solving the problem of the volume variation of the cam-follower mechanism a combination of the proposed designs is optimal. Moreover, among the presented designs, the mechanism with an inclined cam surface with an aluminum shaft is shown to have the highest precision and performance with respect to the other three.
Abstract: Cam-follower mechanism efficiency in production of desired motions has been proved along the history of space missions. In this paper, according to pre-specified spatial condition of wide temperature variations between -100 and +120 Celsius degrees, some new and innovative cam-follower profile designs are presented. In the first follower mechanism,...
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