• Journal of the Korea Society for Simulation
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• v.5 no.1
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• pp.29-29
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• 1996

This paper describes a new automated simulation system for micromachines whose size range $10^{-6}$ to $10^{-3}$ m. An automic finite element (FE) mesh generation technique, which is bases on the fuzzy knowledge processing and computation al geometry technique, is incorporated into the system, together with one of commerical FE analysis codes, MARC, and one of commerical solid modelers, Designbase. The system allows a geometry model of concern to be automatically converted to different FE models, depending on physical phenomena of micromachines to be analyzed, i,e. electrostatic analysis, stress analysis, modal analysis and so on. The FE models are then automatically analyzed using the FE analysis code. Among a whole process of analysis, the definition of a geometry model, the designation of local node patterns and the assignment of material properties and boundary conditions onto the geometry model are only the interactive process to be done by a user. The interactive operations can be processed in a few minutes. The other processes which are time consuming and labour-intensive in conventional CAE systems are fully automatically performed in a popular engineering workstation environment. This automated simulation system is successfully applied to evaluate an electrostatic micro wobble actuator.

• Journal of the Korea Society for Simulation
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• v.5 no.1
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• pp.28-42
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• 1996

This paper describes a new automated simulation system for micromachines whose size range $10^{-6}$ to $10^{-3}$ m. An automic finite element (FE) mesh generation technique, which is bases on the fuzzy knowledge processing and computation al geometry technique, is incorporated into the system, together with one of commerical FE analysis codes, MARC ,and one of commerical solid modelers, Designbase. The system allows a geometry model of concern to be automatically converted to different FE models, depending on physical phenomena of micromachines to be analyzed , i,e. electrostatic analysis, stress analysis, modal analysis and so on. The FEmodels are then automatically analyzed using the FE analysis code, Among a whole process of analysis, the definition of a geometry model, the designation of local node patterns and the assignment of material properties and boundary conditions onto the geometry model are only the interactive process to be done by a user. The interactive operations can be processed in a few minutes. The other processes which are time consuming and labour-intensive in conventional CAE systems are fully automatically performed in a popular engineering workstation environment. This automated simulation system is successfully applied to evaluate an electrostatic micro wobble actuator.

• The KIPS Transactions:PartC
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• v.12C no.7 s.103
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• pp.981-988
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• 2005

Administrative Role-Based Access Control(ARBAC) is a typical model for decentralized authority management by plural security administrators. They have their work range on the role hierarchy. A problem is that legal modification of role hierarch may induce unexpected side effect. Role-Role Assignment 97(RRA97) model introduced some complex integrity principles to prevent the unexpected side effect based on geometric approach. We introduce simple and new one integrity principle based on simple set theory. It is simple and intuitive. It can substitute for all integrity principles of RRA97 model.

• Journal of the Korean Society of Safety
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• v.31 no.6
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• pp.74-83
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• 2016

The purpose of this study was to identify the educational and ecological factors (environment and infra-structure) associated with workers' participation to safety and health education at work (SHEW) based on the PRECEDE constructs. A total of 590 workers (484 in manufacturing and 106 in construction companies) finished the self-administered survey. Survey packets were delivered to the safety and health manager (SHM) in survey companies and the SHMs conducted the self-administered survey in their companies. The questionnaire includes demographics, epidemiological constructs, and educational and ecological constructs based on the PRECEDE model. Participation to SHEW was better in the manufacturing sector than in the construction sector (p<.001). Environmental, reinforcing, and enabling factors were better in the manufacturing companies than in the construction companies. Male worker, better perceived efficacy of SHEW, higher social support for SHEW, assignment of SHM at work, and better safety and health management level at work were significantly associated with workers' better participation to SHEW (p<.05). Those factors accounted for 45.9% of total variance of workers' participation to SHEW.

• Journal of The Korean Society of Agricultural Engineers
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• v.60 no.5
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• pp.95-104
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• 2018

The purpose of this study was to explore the extent of difficulties experienced by facilitators in the rural field forum and to derive a theoretical model for improving the satisfaction of facilitators in the rural field forum. Based on grounded theory, qualitative analysis used data collected through individual in-depth interviews with 10 facilitators who are working at the rural field forum. This collected data was analyzed using the Nvivo 11 program. Using a derived theoretical model, the result of analyzing the difficulties experienced by facilitators in the rural field forum showed the core phenomenon identified as difficulties on-site the forum. There was a clarification of the issues regarding improvement of their labour conditions in order to solve the difficulties on-site the forum. The issues towards improving labour conditions were low allowance, equal assignment, guaranteed four major insurances and so on. The facilitators have been trying to activate the rural field forum by promoting their own capacity through the cooperation between colleagues, post training, seminars, and conferences.

• Industrial Engineering and Management Systems
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• v.4 no.1
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• pp.82-93
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• 2005

Facility layout problems (FLP) are usually treated as design problems. Lack of systematic and objective tools to compare design alternatives results in decision-making to be dominated by the experiences or preferences of designers or managers. To increase objectivity and effectiveness of decision-making in facility layout selections, a decision support model is necessary. We proposed a decision model, which regards the FLP as a multi-attribute decision making (MADM) problem. We identify sets of attributes crucial to layout selections, quantitative indices for attributes, and methods of ranking alternatives. For a requested facility layout design, many alternatives could be developed. The enormous alternatives, various attributes, and comparison of assigned qualitative values to each attribute, form a complicated decision problem. To treat facility layout selection problems as a MADM problem, we used the linear assignment method to rank before selecting those high ranks as candidates. We modelled the application of the Nemawashi process to simulate the group decision-making procedure and help efficiently achieve agreement. The electronics manufacturing service (EMS) industry has frequent and costly facility layout modifications. Our models are helpful to them. We use an electronics manufacturing service company to illustrate the decision-making process of our models.

• Korean Journal of Remote Sensing
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• v.23 no.1
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• pp.33-42
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• 2007

In this paper, an iterative MAP approach using a Bayesian model based on the lognormal distribution for image intensity and a GRF for image texture is proposed for despeckling the SAR images that are corrupted by multiplicative speckle noise. When the image intensity is logarithmically transformed, the speckle noise is approximately Gaussian additive noise, and it tends to a normal probability much faster than the intensity distribution. MRFs have been used to model spatially correlated and signal-dependent phenomena for SAR speckled images. The MRF is incorporated into digital image analysis by viewing pixel types as slates of molecules in a lattice-like physical system defined on a GRF Because of the MRF-SRF equivalence, the assignment of an energy function to the physical system determines its Gibbs measure, which is used to model molecular interactions. The proposed Point-Jacobian Iterative MAP estimation method was first evaluated using simulation data generated by the Monte Carlo method. The methodology was then applied to data acquired by the ESA's ERS satellite on Nonsan area of Korean Peninsula. In the extensive experiments of this study, The proposed method demonstrated the capability to relax speckle noise and estimate noise-free intensity.

• Journal of Digital Convergence
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• v.11 no.2
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• pp.205-214
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• 2013

Team collaboration is becoming commonplace and it is spotlighted in agile software development projects as well. More efficient teamwork in terms of effective team operation and project performance is very important. Heuristic software development staffing method has been used, but algorithm approach is needed to compensate for it. In this paper, we propose a mathematical approaches for staffing developers in teamwork-based software development projects. This consist of six process, and activities in each processor is defined as a mathematical function placement, and functional deployment matrix is used. A case study is presented in order to prove the usefulness of this approach. This paper is a significant research because a mathematical approach of work assignment is developed for human resources by quantitative logic and it deviate from intuitive or heuristic methods used previously.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.40 no.10
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• pp.67-78
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• 2003

As optical network technology advances and high bandwidth Internet is demanded for the exponential growth of internet traffic volumes, the Dense-Wavelength Division Multiplexing (DWDM) networks have been widely accepted as a promising approach to the Next Generation Optical Internet (NGOI) backbone networks for nation wide or global coverage. Important issues in the NGOI based on DWDM networks are the Routing and Wavelength Assignment(RWA) problem and survivability. Especially, fault/attack detection, localization and recovery schemes in All Optical Transport Network(AOTN) is one of the most important issues because a short service disruption in DWDM networks carrying extremely high data rates causes loss of vast traffic volumes. In this paper, we suggest a fault/attack management model for NGOI through analyzing fault/attack vulnerability of various optical backbone network devices and propose fault/attack recovery procedure considering Extended-LMP(Link Management Protocol) and RSVP-TE+(Resource Reservation Protocol-Traffic Engineering) as control protocols in IP/GMPLS over DWDM.

• Journal of the Korean School Mathematics Society
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• v.1 no.1
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• pp.139-149
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• 1998

The purpose of this study is to check out whether the method that students make problems and anouence them to both students and teacher in the next class influence on the students' intersts, attitudes, logical thinking ability and lerning achievement in mathematics. The following is the experimental design and procedure. First, the author divided students into two groups. One is the experimental group and the other is the control group. These two groups' students consist of the advanced level, the intermediate level and the elementary level according to the students' learning proficiency Second, the author used the different teaching method between the experimental group and the control group. The author gave the experimental group's students the learning assignment problems according to their three levels and made students present the problems to the instructor and classmates in the next class. On the other hand, the author gave the control group's students learning assignment problems according to their three levels, and made them only submit their assingment to the instructor. The results of this study are as follows : 1)The method of solving and presenting the self-made problems on the basis of the informations to solve the given preceding model learning problems according to students' levels made students' learning attitudes more positive even though the method couldn't enhance the students' interests in mathematics. 2)The method of solving and presenting the self-made problems was effective to improve the logical thinking ability for especially the intermediate level's students among the three levels. In addition, the intermediate level's students showed great positive changes in their improvements of the learning achievment. It is assumed that this result is caused by two major factors(reasons). One is students' confidence that they can solve the fundamental problems without difficulty. And the other is students' desire to solve the problems of the intermediate level or more advanced level.