• Journal of Korean Society for Quality Management
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• v.45 no.4
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• pp.829-846
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• 2017

Purpose: This paper compares the effectiveness of typical selective assembly criteria and suggests the most promising one. Based on the result of a computer simulation, the key issues of selective assembly are examined and the best criterion is recommended from the effectiveness perspective. Methods: Using JAVA program, production of ten thousand units for each pair of components are simulated for selective assembly of the two types. And the number of mismatching and the fraction nonconforming for each criterion are determined. Results: The best match criterion appeared to be most promising from the perspectives of both mismatching and nonconforming problems. Its effectiveness appears to be also good even when the precision of one component is different from that of the other. Conclusion: For designing an optimal method for selective assembly, the best match criterion is recommendable as the base criterion.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2022.10a
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• pp.15-17
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• 2022

In order to minimize surplus parts in ball bearing selective assembly systems, it is necessary to optimize the selection probability by grasping the dimensional distribution of each part. But the use of a complex system causes delays in the production process. In this paper, we propose cluster priority selection algorithm that can quickly and simply determine the selection priority in ball bearing selective assembly system. In addition, we assume the simulated situation with the data collected in the actual ball bearing selective assembly process, and evaluate the incidence of surplus part and runtime by simulating the cluster priority selection algorithm and the exiting algorithm. As a result of the simulation, the cluster priority selection algorithm generated 83.8% less surplus parts, and 39.7% less runtime than the existing algorithm.

• Journal of the Korean Operations Research and Management Science Society
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• v.24 no.1
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• pp.39-48
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• 1999

An economic procedure of selective assembly is proposed when a product is composed of two mating components. The major qualify characteristic of the product is the clearance between the two components. The components are divided into several classes prior to assembly. The component characteristics are assumed to be independently and normally distributed with equal variance. The procedure is designed so that the proportions of both components in their corresponding classes are the same. A cost model is developed based on a quadratic loss function and methods of obtaining the optimal class limits as well as the optimal number of classes are provided. Formulas for obtaining the proportion of rejection and the unavailability of mating components are also provided. The proposed model is compared with the equal width and the equal area partitioning methods using a numerical example.

• Proceedings of the Korean Vacuum Society Conference
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• 2009.02a
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• pp.110.2-110.2
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• 2009

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2005.05a
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• pp.740-745
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• 2005

Selective assembly is a method to find out appropriate matching pairs to be assembled to enhance the quality of the product. This study proposes an algorithm to select and match the components with two performance characteristics: at first, the number of matchable mates are calculated for each components. A matchable mate is defined to be the one of which the values of each performance characteristics lie in a rectangular mesh originated from the component under consideration. And the highest priority is given to the item with smallest number of matchable mates. The item of highest priority is matched to the one with smallest number of matchable mates among them. To find out the mates for the unmatched items, the mesh size is enlarged at the next iteration. Beginning with a small mesh, the procedure is repeated until the mesh covers the tolerance intervals of each performance characteristics. A VCR head case is analyzed.

• Macromolecular Research
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• v.9 no.4
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• pp.185-196
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• 2001

The self-assembly of block copolymers can lead to a variety of ordered structures on a nanometer scale. In this article, the self-assembling behaviors of triblock copolymers in the melt and the selective solvent are described with the results obtained from the computer simulations. With the advances of computing power, computer simulations using molecular dynamics and Monte Carlo techniques make it possible to study very complicated phenomena observed in the self-assembly of triblock copolymer. 13king full advantage of the computer simulation based on well-defined model, the effects of various structural and thermodynamic parameters such as the copolymer composition, the block sequence, the pairwise interaction energies, and temperature on the self-assembly are discussed in some detail. Some simulation results are compared with experimental ones End analyzed by comparing them with the theoretical treatment.

• Textile Coloration and Finishing
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• v.25 no.1
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• pp.13-17
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• 2013

A new assembly derived from 2,3-dibromo-5,6,7,8-tetrafluoroquinizarin and sodium diethyl-carbamodithiolate, was prepared as an efficient $Fe^{3+}$ colorimetric chemosensor with high selectivity over other cations $Fe^{3+}$, $Na^+$, $Mg^{2+}$, $Pb^{2+}$, $Cd^{2+}$, $Ni^{2+}$, $Ca^{2+}$, $Cu^{2+}$, $Hg^{2+}$, $Zn^{2+}$ : from the dark blue to brown color change that is visible by eyes. This assembly produced large bathochromic shift of 228 nm in the presence of $Fe^{3+}$ compared with the corresponding absorption maximum of the parent dye.

• Nuclear Engineering and Technology
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• v.55 no.2
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• pp.674-680
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• 2023

The brine and seawater are important and largely untapped sources of critical trace metals and elements. The coupling of selective recovery of trace metals from seawater/brine with desalination plants gives an added advantage of energy credits to desalination plants and as well as reduce the cost of desalinated water. In this paper, status review on recovery of important trace metals and other alkali metals from seawater is presented. The potential of Indian desalination plants for recovery of trace metals, based on recovery ratio of 0.35 is also highlighted. Studies carried out by the process based on adsorption using Radiation Induced Grafted (RIG) polymeric adsorbents and then fractional elutions are presented. The fouling factors due to bio fouling and dirt fouling have been estimated for various locations of interest through field trails. The pay loader in the form of compact Contactor Assembly with minimum pressure drop, for loading specially designed radiation grafted sorbent in leaflet form has been briefed, as required for plant scale facility. The typical conceptual process design details of farm assembly of project CRUDE are described.

• Journal of the Korean Society of Industry Convergence
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• v.7 no.2
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• pp.193-198
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• 2004

This is the dissertation of the study of design characteristics about the practical flexible manufacturing system (PFMS). The basic ideas to analyze the manufacturing system which is the automatically operated is dependant on the various manufacturing procedures in factory. PFMS is the very useful equipment for students and trainee of production lines. This system is composed of hardware and software sub systems i.e. control and test unit and personal computer with software. The PFMS can be developed with design concepts and approved the capability of first article with functional tests. The PFMS module will be very useful for the manufacturing drill system in universities and practical fields. The flexible manufacturing systems have various subsystems appropriated for the final manufacturing products. Therefore the systems have the various kinds of hard wares as well as softwares. We study the software for the practical flexible manufacturing system designed in the Halla University and specially the design concept and using specification of the SCARA (Selective Compliance Assembly Robot Arm) robot which is used for the movement of the product is analyzed and introduced in this dissertation.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.05a
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• pp.6.1-6.1
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• 2011

Nanoscale block copolymer (BCP) patterns have been pursued for applications in sub-30 nm nanolithography. BCP self-assembly processing is scalable and low cost, and is well-suited for integration with existing semiconductor fabrication techniques. However, one of the major technical challenges for BCP self-assembly is limited tunability in pattern geometry, dimension, and functionality. We suggest methods for extending the degree of tunability by choosing highly incompatible polymer blocks and utilizing solvent vapor treatment techniques. Siloxane BCPs have been developed as self-assembling resists due to many advantages such as high etch-selectivity, good etch-resistance, long-range ordering, and reduced line-edge roughness. The large incompatibility leads to extensive degree of pattern tunability since the effective volume fraction can be easily manipulated by solvent-based treatment techniques. Thus, control of the microdomain size, periodicity, and morphology is possible by changing the vapor pressure and the mixing ratio of selective solvents. This allows a range of different pattern geometry such as dots, lines and holes and critical dimension simply by changing the processing conditions of a given block copolymer without changing a polymer chain length. We demonstrate highly extensive tunability (critical dimension ~6~30 nm) of self-assembled patterns prepared by a siloxane BCP with extreme incompatibility.