• Journal of Korean Institute of Industrial Engineers
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• v.13 no.2
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• pp.117-128
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• 1987

A major problem in the adoption of advanced manufacturing systems such as F.M.S. (Flexible Manufacturing Systems) is the prerequisite economic justification process because of high investment needed for the acquisition and installation of F.M.S. While some of the benefits expected are readily quantifiable, others are very difficult or even impossible, using conventional method. Thus the investment in F.M.S. should be considered as a strategic decision rather than a tactical decision which concerns with only financial implications. In this paper we review papers on major justification techniques developed during thelast decade and identify the benefits of F.M.S. and describe the considerations in the justification of F.M.S. Also, we deal with the current and future research directions in justifying F.M.S.

• Journal of the korean society of oceanography
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• v.39 no.4
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• pp.222-233
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• 2004

Using nitrogen as the limiting nutrient, the default version of a microplankton-detritus model linked chlorophyll concentration to the autotroph nitrogen. However, phosphorus dynamics were added to simulate the results of a microcosm experiment. Using standard parameter values with a single value of microheterotroph fraction in the microplankton taken from the observed range, the best simulation successfully captured the main features of the time-courses of chlorophyll and particulate organic carbon, nitrogen and phosphorus, with root-mean-square error equivalent to 29% of particulate concentration. A standard version of microbiological model assumes complete internal cycling of nutrient elements; adding a term for ammonium and phosphate excretion by microheterotrophs did not significantly improve predictions. Relaxing the requirement for constant microheterotroph fraction resulted in an autotroph-heterotroph model AH, with dynamics resembling those of a Lotka-Volterra predator-prey system. AH fitted the microcosm data worse than did MP, justifying the suppression of Lotka-Volterra dynamics in MP. The paper concludes with a discussion of possible reasons for the success of the simple bulk dynamics of MP in simulating microplankton behaviour.

• Advances in concrete construction
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• v.5 no.1
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• pp.1-15
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• 2017

This research project aimed at evaluating experimentally the effect of natural perlite powder as an alternative supplementary cementing material (SCM) on the performance of fiber reinforced self-consolidating repair mortars (FR-SCRMs). For this purpose, four FR-SCRMs mixes incorporating 0%, 10%, 20%, and 30% of natural perlite powder as cement replacements were prepared. The evaluation was based on fresh (slump flow, flow time, and unit weight), hardened (air-dry unit weight, compressive and flexural strengths, dynamic modulus of elasticity), and durability (water absorption test) performances. The results reveal that structural repair mortars confronting the performance requirements of class R4 materials (European Standard EN 1504-3) could be designed using 10%, 20%, and 30% of perlite powder as cement substitutions. Bonding results between repair mortars containing perlite powder and old concrete substrate investigated by the slant shear test showed good interlocking justifying the effectiveness of these produced mortars.

• Journal of Korean Elementary Science Education
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• v.38 no.2
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• pp.163-172
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• 2019

This study explored elementary teachers' perceptions on the essential features of science inquiry, the appropriateness of inquiry activities to science inquiry, and the essential features of inquiry by inquiry activities. 85 elementary teachers' perceptions were investigated using Likert scale survey, and 7 teachers were interviewed. The results are as follows. First, the features that elementary teachers perceived the most essential were 'Engaging students in evaluating their explanations in light of alternative explanations' and 'Engaging students in communicating and justifying their explanations'. Second, The inquiry activities that teachers thought the most appropriate to science inquiry were 'experiment' and 'project'. On the other hand, the perceptions on 'discussion' and 'field trip' were relatively low. Third, the inquiry activity that showed the highest mean score of five essential features of inquiry was 'experiment' while the mean score of 'field trip' was the lowest. Educational implications about the science inquiry were discussed.

• Nuclear Engineering and Technology
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• v.54 no.6
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• pp.2244-2252
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• 2022

Based on GIS technologies, a decision support system (GIDSS) has been developed to remediate agricultural lands in the Bryansk region (Russia) contaminated by ¹³⁷Cs after the accident at the Chernobyl nuclear power plant. GIDSS is a multilevel system consisting of basic, information and computational layers. GIDSS allows justifying a targeted approach for the remediation of agricultural lands belonging to agricultural enterprises for the production that meets the established radiological requirements for the content of radionuclides. Evaluation of the effectiveness of alternative remediation technologies and the selection of optimal measures were carried out at the level of elementary plots using radiological criteria. The introduction of GIDSS will enable agricultural producers in the south-western districts of the Bryansk region to conduct radiation-safe agro-industrial production in radioactively contaminated areas, which will help improve the socio-economic situation of the region and return it to normal living conditions.

• Journal of Korean Association for Spatial Structures
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• v.24 no.1
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• pp.65-72
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• 2024

This paper aims to advance our understanding of extensible beams with multiple cracks by presenting a crack energy and motion equation, and mathematically justifying the energy functions of axial and bending deformations caused by cracks. Utilizing an extended form of Hamilton's principle, we derive a normalized governing equation for the motion of the extensible beam, taking into account crack energy. To achieve a closed-form solution of the beam equation, we employ a simple approach that incorporates the crack's patching condition into the eigenvalue problem associated with the linear part of the governing equation. This methodology not only yields a valuable eigenmode function but also significantly enhances our understanding of the dynamics of cracked extensible beams. Furthermore, we derive a governing equation that is an ordinary differential equation concerning time, based on orthogonal eigenmodes. This research lays the foundation for further studies, including experimental validations, applications, and the study of damage estimation and detection in the presence of cracks.

• Journal of the Korean Geographical Society
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• v.42 no.5
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• pp.745-760
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• 2007

This study aims to categorize and analyze internationally standardized sea names based on their origins. Especially noting the cases of sea names using country names and dual naming of seas, it draws some implications for complementing logics for restoring the name East Sea. Of the 110 names for 98 bodies of water listed in the book titled Limits of Oceans and Seas, the most prevalent cases are named after adjacent geographical features; followed by commemorative names after persons, directions, and characteristics of seas. These international practices of naming seas are contrary to Japan's argument for the principle of using the name of archipelago or peninsula. There are several cases of using a single name of country in naming a sea bordering more than two countries, with no serious disputes. This implies that a specific focus should be given to peculiar situation that the name East Sea contains, rather than the negative side of using single country name. In order to strengthen the logic for justifying dual naming, it is suggested, an appropriate reference should be made to the three newly adopted cases of dual names, in the respects of the history of the surrounding region and the names, people's perception, power structure of the relevant countries, and the process of the standardization of dual names. In order to endow East Sea with the meaning of the east of the Eurasian continent, westerners' perception on the Far East should be elaborated in more detail.

• Journal of Radiation Protection and Research
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• v.42 no.2
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• pp.114-129
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• 2017

Background: The purpose of this paper is to confirm the event timings and the magnitude of fission product aerosol release from the Fukushima accident. Over a few hundreds of technical papers have been published on the environmental impact of Fukushima Daiichi accident since the accident occurred on March 11, 2011. However, most of the research used reverse or inverse method based on the monitoring of activities in the remote places and only few papers attempted to estimate the release of fission products from individual reactor core or from individual spent fuel pool. Severe accident analysis code can be used to estimate the radioactive release from which reactor core and from which radionuclide the peaks in monitoring points can be generated. Materials and Methods: The basic material used for this study are the initial core inventory obtained from the report JAEA-Data/Code 2012-018 and the given accident scenarios provided by Japanese Government or Tokyo Electric Power Company (TEPCO) in official reports. In this research a forward method using severe accident progression code is used as it might be useful for justifying the results of reverse or inverse method or vice versa. Results and Discussion: The release timing and amounts to the environment are estimated for volatile radioactive fission products such as noble gases, cesium, iodine, and tellurium up to 184 hours (about 7.7 days) after earthquake occurs. The in-plant fission product behaviors and release characteristics to environment are estimated using the severe accident progression analysis code, MELCOR, for Fukushima Daiichi accident. These results are compared with other research results which are summarized in UNSCEAR 2013 Report and other technical papers. Also it may provide the physically based arguments for justifying or suspecting the rationale for the scenarios provided in open literature. Conclusion: The estimated results by MELCOR code simulation of this study indicate that the release amount of volatile fission products to environment from Units 1, 2, and 3 cores is well within the range estimated by the reverse or inverse method, which are summarized in UNSCEAR 2013 report. But this does not necessarily mean that these two approaches are consistent.

• Korean Journal of Culture and Social Issue
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• v.27 no.4
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• pp.391-410
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• 2021

The purpose of this study is to explore the mediating effect of violence justification, including actor-effect and partner-effect, in the process where the offense motive affects dating violence. The subjects of this study were 135 unmarried male and female couples aged 19 and over who were dating for more than 3 months, and each couple was subjected to a self-report scale on motives, justification of violence, and dating violence. Based on these paraphrasing, as a result of analyzing the path model using the Actor-Partner Interdependence Model, Men and women's motivations showed a direct effect on their dating violence, while women's motivations showed a significant partner effect on men's violence. The male's motivation also had a significant impact on his dating violence and partner's abuse of dating violence as a mediator for justification of his violence. On the other hand, the mediating effect of justifying violence in women was not significant. These results show that there is a gender difference between the motives for violence and the paths for justifying violence in the sex violence of men and women. Finally, the implications and limitations of this study, and suggestions for follow-up studies were discussed.

• Journal of Korean Institute of Industrial Engineers
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• v.11 no.1
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• pp.21-32
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• 1985

Presented in this paper is a procedure of developing graphical simulation software for planning robot welding processes. Welding is by far the highest application area for industrial robots, and it has been in great need of such a simulator in designing robot work cells, in justifying the economics of robot welding and in planning robotized welding operations. The model of a robot welding cell consists of four components: They are an welding structure which is a collection of plates to be welded, a positioner to hold the welding structure, a robot with a weld torch, and a set of welding lines (in case of arc welding). Welding structure is modeled by using the reference plane concept and is represented as boundary file which is widely used in solid modeling. Robot itself is modeled as a kinematic linkage system. Also included in the model are such technical constraints as weaving patterns and inclination allowances for each weld joint type. An interactive means is provided to input the welding structure and welding lines on a graphics terminal. Upon completion of input, the program displays the welding structure and welding lines and calculates the center of mass which is used in determining positioner configurations. For a given positioner and robot configuration, the welding line segments that can be covered by the robot are identified, enabling to calculate the robot weld ratio and cycle time. The program is written in FORTRAN for a VAX computer with a Tektronix 4114 graphic terminal.