• Nuclear Engineering and Technology
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• v.56 no.5
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• pp.1672-1678
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• 2024

We introduce a creative approach combining machine learning with optimization techniques to enhance the optimization of the loading pattern (LP). Finding the optimal LP is a critical decision that impacts both the reload safety and the economic feasibility of the nuclear fuel cycle. While simulated annealing (SA) is a widely accepted technique to solve the LP optimization problem, it suffers from the drawback of high computational cost since LP optimization requires three-dimensional depletion calculations. In this note, we introduce a technique to tackle this issue by leveraging neural networks to filter out inappropriate patterns, thereby reducing the number of SA evaluations. We demonstrate the efficacy of our novel approach by constructing a machine learning-based optimization model for the LP data of the Korea Standard Nuclear Power Plant (OPR-1000).

• Journal of the Korean Society for Precision Engineering
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• v.17 no.3
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• pp.47-57
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• 2000

In this study, PC-based dicing machine and driving software were constructed for the purpose of automation of wafer cutting process. To automate the machine, hard automation including vision, loading, and software were considered in the development. Auto loading device and vision system were adopted for the increase of productivity, GUI software programmed for the expedient operation. The dicing machine is operated by the control algorithm and some parameters. It is verified that this kind of PC based automation has a great potential compared with the conventional dicing machine when applied to manufacturing some kinds of wafers as a test purpose.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.536-539
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• 2002

In this paper, we developed the automatic optical fiber aligner by image processing and automatic loading system. Optical fiber is indispensable for optical communication systems that transmit large volumes of data at high speed, but super-precision technology in sub-micron units is required for optical axis adjustment, we have developed 6-axis micro stage system for I/O optical fiber arrays, the initial automatic aligning system/software for a input optical array by the image processing technique, fast I/O-synchronous aligning strategy, the automatic loading/unloading system and the automatic UV bonding mechanism. In order to adjust the alignment it used on PC based motion controller, a $10\mu\textrm{mm}$ repeat-detailed drawing of automatic loading system is developed by a primary line up for high detailed drawing. Also, at this researches used the image processing system and algorithm instead of the existing a primary hand-line up. and fiber input array and waveguide chip formed in line by automatic. Therefore, the developed and manufactured optical aligning system in this research fulfills the great role of support industry for major electronics manufacturers, telecommunications companies, universities, government agencies and other research institutions.

• Steel and Composite Structures
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• v.29 no.3
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• pp.309-318
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• 2018

Steel girders are the structural members often used for passing long spans. Mostly being subjected to patch loading, or concentrated loading, steel girders are likely to face sudden deformation or damage e.g., web breathing. Horizontal or vertical stiffeners are employed to overcome this phenomenon. This study aims at assessing the feasibility of a machine learning method, namely the support vector machines (SVM) in predicting the patch loading resistance of longitudinally stiffened webs. A database consisting of 162 test data is utilized to develop SVM models and the model with best performance is selected for further inspection. Existing formulations proposed by other researchers are also investigated for comparison. BS5400 and other existing models (model I, model II and model III) appear to yield underestimated predictions with a large scatter; i.e., mean experimental-to-predicted ratios of 1.517, 1.092, 1.155 and 1.256, respectively; whereas the selected SVM model has high prediction accuracy with significantly less scatter. Robust nature and accurate predictions of SVM confirms its feasibility of potential use in solving complex engineering problems.

• Steel and Composite Structures
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• v.34 no.6
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• pp.877-889
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• 2020

This work features the outcomes of an empirical investigation into the characteristics of steel reinforced grout (SRG) composite - concrete interfaces. The parameters varied were loading rate, densities of steel fibres and types of load displacement responses or measurements (slip and machine grips). The following observations and results were derived from standard single-lap shear tests. Interfacial debonding of SRG - concrete joints is a function of both fracture of matrix along the bond interface and slippage of fibre. A change in the loading rate results in a variation in peak load (P_max) and the correlative stress (σ_max), slip and machine grips readings at measured peak load. Further analysis of load responses revealed that the behaviour of load responses is shaped by loading rate, fibre density as well as load response measurement variable. Notably, the out-of-plane displacement at peak load increased with increments in load rates and were independent of specimen fibre densities.

• Journal of Korean Institute of Industrial Engineers
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• v.29 no.1
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• pp.65-77
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• 2003

This paper addresses FMS(Flexible Manufacturing System) loading problems with machine, tool and process flexibilities. When designing FMS planning, it is important to take account of these flexibilities for an efficient utilization of the resources. However, almost all the existing researches do not appropriately consider various flexibilities due to the problem complexity. This paper presents a new evolutionary algorithm to solve the FMS loading problems with machine, tool and process flexibilities. The algorithm is named a multi-level symbiotic evolutionary algorithm. The proposed algorithm is compared with the existing ones in terms of solution quality and convergence speed. The experimental results confirm the effectiveness of our approach.

• Journal of the Korean Society of Safety
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• v.9 no.1
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• pp.31-39
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• 1994

In this study, image processing were performed to recognize the shape of objects and find its center coordinate and direction to grisp the objects by the robot automatically. The proposed methods could be applied to objects even if light is reflected, and to identify the insides and outsides of objects by using the photo sensor and the difference of surface conditions. Also image segmentation is performed to the objects close to each other. These image processing methods will be increased the safety of operators by the automation of dangerous and hazardous machine works.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.9 no.4
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• pp.34-47
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• 2000

Since carbon fiber epoxy composite materials have excellent properties for structures due to their high specific strength, high specific modulus, high damping and low thermal expansion, the hollow shafts made of carbon fiber epoxy composites have been widely used for power transmission shafts for motor vehicles , spindles of machine tools, motor base, bearing mount for tool up and manufacturing. The molded composite machine elements are not usually accurate enough for mechanical machine elements, which require turning drilling , cutting and grinding. The experiment are surface grinding wheel GC60 to the carbon fiber epoxy composite specimen with respect to staking angle [0]nT , [45]nT, [90]nT on the CNC grinding machine. In this paper, the surface grinding characteristics of composite plate, which are surveyed experimentally and analytically with respect to the grinding force, surface roughness and wheel loading according to the variable depth of cut, wheel velocity and table feed rate are investigated.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.04a
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• pp.602-607
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• 1997

Ball balance belong to a kind of automatic balancers opten referred to as direct balancer or passive mass systems. In such systems the balancing is achieved with free masses. One of the most prevalent problems encountered in washing is the vibration during spin cycle. The primary cause of this vibration is mass unbalance associated with non unform distribution of clothes. Front loading type machine of European style, especially, has inherent unbalance mass due to its shape and this then makes the vibration worse than top loading type machine, which is more popular in Korea. Since the mass distribution of cloths is random and can not be predicted in advance, direct automatic balances appear to be the only feasible alternative. The results form computer simulation and experimental testing will be presented together with stability implications.

• Journal of the Korean Society of Industry Convergence
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• v.24 no.3
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• pp.363-371
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• 2021

Forest operations like timber harvesting have already been mechanized to reduce hazards to the worker and increase productivity. However, timber harvesting operations have still been considered potentially dangerous and expensive on steep terrain. Teleoperation, to control the timber harvesting machine at a distance, has the potential to improve the safety, productivity and efficiency of harvesting operations on steep terrain. To verify the effects of teleoperation, an experimental prototype system of a monitor image-based teleoperation was constructed using a real forestry machine. In this study, the productivity of excavator based grapple loader, which is one of the most used mechanized harvesting equipment in the timber production, was analyzed using time-study method. Factors like skill and age of operators, influencing loader productivity in timber loading operation were also evaluated by statistical analysis. Productivity analysis results showed that less experienced operators were more productive than experienced operators for teleoperation through image of monitors in the operator cabin. These results are shown to be unfamiliar to the monitor image and different loading operation pattern by operators. According to the results, the monitor image-based teleoperation system of forestry machine need to improve the resolution and installation position of camera. It was expected that additional studies will be needed for real-time remote control of forestry machine in the future.