• Journal of Institute of Control, Robotics and Systems
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• v.12 no.12
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• pp.1197-1201
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• 2006

In order to improve the operability in a fully thermally coupled distillation column the main column is separated into an upper and a lower column, and its design method is explained. With a distillation experiment using a two-inch column the operability of the proposed column is examined. Readily available methanol, ethanol and propanol are used as the feed, and the experimental result is compared with that of the HYSYS simulation. It is found from the experiment that the recovery ranges between 58.8% and 68% and the distillation efficiency is lower than that of the simulation. consumes less energy than an original column, it is not widely implemented in practice due to its operational difficulty. However, it is proved that the proposed distillation column can be operated without compressors and it can be practically utilized.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.38 no.4
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• pp.98-108
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• 2015

This paper introduces the existence of purchase dependence that was identified during the analysis of inventory operations practice at a sales agency of dealing with spare parts for ship engines and generators. Purchase dependence is an important factor in designing an inventory replenishment policy. However, it has remained mostly unaddressed. Purchase dependence is different from demand dependence. Purchase dependence deals with the purchase behavior of customers, whereas demand dependence deals with the relationship between item-demands. In order to deal with purchase dependence in inventory operations practice, this paper proposes (Q, r) models with the consideration of purchase dependence. Through a computer simulation experiment, this paper compares performance of the proposed (Q, r) models to that of a (Q, r) model ignoring purchase dependence. The simulation experiment is conducted for two cases : a case of using a lost sale cost and a case of using a service level. For a case of using a lost sale cost, this paper calculates an order quantity, Q and a reorder point, r using the iterative procedure. However, for a case of using a service level, it is not an easy task to find Q and r. The complexity stems from the interactions among inventory replenishment policies for items. Thus, this paper considers the genetic algorithm (GA) as an optimization method. The simulation results demonstrates that the proposed (Q, r) models incur less inventory operations cost (satisfies better service levels) than a (Q, r) model ignoring purchase dependence. As a result, the simulation results supports that it is important to consider purchase dependence in the inventory operations practice.

• Journal of Digital Convergence
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• v.18 no.6
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• pp.389-399
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• 2020

This study was conducted to identify the effects of fundamental nursing practice education using flipped learning on self confidence performance, academic achievement and critical thinking. The subjects of this study were 38 experimental groups and 36 control groups, who were in the second year of the department of nursing at D university, and Flip learning was applied to the experimental group for four weeks, while the existing teaching methods were applied to the control group. As a result, the academic achievement of vital signs in the experimental group after the experiment with flip learning was significantly higher than the control group (t=2.921, p=.005), but other variables were not significant. In addition, the critical thinking of the experimental group was significantly increased after the experiment than before (t=2.277 p=.029). However, it was not significant in the control group. In the future, various studies using flip learning in nursing are needed.

• Proceedings of the KIEE Conference
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• 2001.07d
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• pp.2600-2602
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• 2001

The laboratory time for students in engineering has to be managed in that way that it provides students width maximal practice hours. However, it usually takes too much time to learn basic knowledge for the experiment and the directions of the equipment. In this paper, we introduce the web contents which students can study basic knowledge the directions of the equipment without regard to time or place. As the result that we let students study the contents before the class, they were easily adapted to handle the equipments for the experiment so that we can revise their execution abilities. And also there were effects such as reducing the total experiment's time and a rate of damage of equipment.

• Journal of the Korean Wood Science and Technology
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• v.37 no.1
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• pp.48-55
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• 2009

In the glulam beam deflection it is necessary to check the reliability of theory formula, because of wood anisotropy and wood qualities (knot, slop of grain). In this experiment, when bending stress occurred on glulam, practice deflection of glulam measuring with AICON DPA-Pro 3D system were compared with prediction deflection calculated as substituting MOE through non-destructive testing and static MOE through bending test in differential equation of deflection curve. MOE using ultrasonic wave tester of laminae, MOE using natural frequencies of longitudinal vibrations ($E_{cu}$, $E_{cf}$), MOE using ultrasonic wave tester of glulam ($E_{gu}$) and MOE using natural frequencies of longitudinal vibrations ($E_{gf}$) were substituted in this experiment. When practice deflection measured by 3D system was compared with prediction deflection calculated with differential equation of deflection curve, within proportional limit the ratio of practice deflection and prediction deflection was similar as 1.12 and 1.14, respectively. Deflection using ultrasonic wave tester was 0.89 and 0.95, Deflection using natural frequencies of longitudinal vibrations was 1.07 and 1.10. The results showed that prediction deflection calculated by substituting using non-destructive MOE of glulam having anisotropy in differential equation of deflection curve was agreed well with practice deflection.

• Journal of The Korean Association For Science Education
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• v.42 no.2
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• pp.253-264
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• 2022

The purpose of this study is to examine the practice of scientists from the perspective of Ian Hacking's 'creation of phenomena'. Scientific phenomena, according to Hacking, are regular and do not exist in nature without the intervention of scientists or experimental tools. This study tries to derive scientific educational meaning by analyzing the thoughts and episodes of the 'Sontanda (inter-individual variability)' phenomenon experienced by four life scientists. The Sontanda phenomenon is a common term used by scientists to describe phenomena in which findings do not appear consistently even when studies are carried out using the same experimental procedure and materials. The following four educational implications were discovered as a result of the research. First, we confirmed the importance of embodied knowledge, or non-verbal knowledge, which solves issues by making appropriate judgments and reactions at all times, rather than simply becoming accustomed to the experimental method. This argues that propositional knowledge and non-verbal knowledge should be handled equally in order to provide students with a practical scientific inquiry. Second, we tried to reconsider the picture of the experiment. The phenomenon revealed in the interviews of scientists is rare, and it takes a long time to stabilize the phenomenon. On the other hand, the image of school experiments is always positive and consistent, necessitating a shift in perspective. Third, the precise meaning of scientific practice could be confirmed. This study confirms that scientists use their knowledge effectively in line with the circumstances, and we examined strategies to apply scientific practice to school instruction based on this. Finally, by provoking uncertainty, the Sontanda phenomena may give students with an opportunity to engage in meaningful scientific involvement. By breaking away from the cookbook experiment, this study expects school experimental education to help in efforts to experience scientific practice.

• Journal of Software Assessment and Valuation
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• v.17 no.2
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• pp.109-116
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• 2021

Traditionally, the engineering field has been dominated by face-to-face education focused on experimental practice, but demand for online learning has soared due to the rapid development of IT technology and Internet communication networks and recent changes in the social environment such as COVID-19. In order for efficient online education to be conducted in the engineering field, where the proportion of experimental practice is relatively high compared to other fields, virtual laboratory practice content that can replace actual experimental practice is very necessary. In this study, we developed a line tracer model and a virtual experimental software to simulate it for efficient online learning of microprocessor applications that are essential not only in the electric and electronic field but also in the overall engineering field where IT convergence takes place. In the developed line tracer model, the user can set various hardware parameter values in the desired form and write the software in assembly language or C language to test the operation on the computer. The developed line tracer virtual experimental software has been used in actual classes to verify its operation, and is expected to be an efficient virtual experimental practice tool in online non-face-to-face classes.

• The Journal of Korean Physical Therapy
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• v.26 no.4
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• pp.234-239
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• 2014

Purpose: The purpose of this study is to use P300 latency to determine whether methods of motor learning in terms of massed and distributed practice can affect motor sequential learning in healthy adults. Methods: Twenty-four healthy subjects participated in this study. They were randomly allocated into three groups: a 10 minute, a 12 hour, and a 24 hour group. In the SRT task, eight numbers were adopted as auditory stimuli. During an experiment, participants were instructed to press the matching key as quickly and accurately as possible when one of the eight numbers was presented randomly. The subjects practiced for three sessions, each of which comprised five blocks of 40 serial reaction time tasks. While they practiced during these three sessions, P300 latency was measured. The data were analyzed using ANCOVA. Results: The P300 latency of Fz, Cz, and Pz decreased in all groups except for the Fz area of the 10 min group. Overall, the P300 latency of the 10 min group showed a smaller decrease compared with the 12 hr and 24 hr groups. Statistically, no significant differences in the Fz and Cz areas were observed among the three groups. The P300 latency in the Pz area of the 10 min group showed a significantly smaller decrease compared with the other groups. Conclusion: These findings suggest that short-term sequential motor training can alter brain functions such as the P300 latency. We also found that better acquisition of a motor skill was obtained with distributed practice of a task than with massed practice.

• Journal of Korean Home Economics Education Association
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• v.31 no.1
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• pp.151-168
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• 2019

This study aims to verify the effects of the sewing practice class, developed for the cultivation of creativity and personality, the two qualities that the Korean Department of Education tried to emphasize in 2009 national curriculum. We conducted a single-group pretest-posttest experiment with the developed sewing practice class as a treatment. Results are as follows. First, the comparison results of before and after the developed sewing practice class showed that there were meaningful differences in creativity and its subfactors such as divergent thinking skill, problem solving ability, open-mindedness and patience. This is because in-class activities such as coming up with ideas by group discussion, creative activities and problem-solving experiences make the students be aware that they are the hosts of the class. It also affected their abilities of producing creative ideas and solving problems proactively. Second, the developed sewing practice class had an impact on students' personality and its subfactors like responsibility, diligence, consideration, communication skill, and collaborative ability. This practice class is based on personal activities which lead to the completion of the group assignment. This has not only emphasized individual responsibilities, but also highlighted the completion of group work and encouraged the flow of communication and cooperation among students. As a result, we concluded that this practice class helped nourish the participating students' personality.

• Korean journal of applied entomology
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• v.23 no.2 s.59
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• pp.96-101
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• 1984

This experiment was carried out to investigate control efficacy by cultural practice and fumigation of tacterial wilt caused by Pseudomonas solancearum in resistant tobacco line NC82 at the Korea Ginseng and Tobacco Research Institute, Eumseong Experiment Station in 1982 and 1983. The bacterial wilt of tobacco occurred severely from mid-July to last August in applicable temperature and soil humidity for increasing bacteria. Disease severity appeared low and slowly at fumigation and resistant variety treatment. Incidence of bacterial wilt in tobacco line NC82 was $44.7\~55.8\%$ being compared with susceptible variety, NC2326 and $95\~99\%$ when resistant variety, NC32 was cultivated with soil fumigation treatment. Control efficacy of cultural practices appeared low with $0.8\~20\%$ and was not different from resistant variety and fumigation treatment. Control system against bacterial wilt in flue-cured tobacco was accomplished by control efficacy over $95\%$ when resistant variety(NC82) was cultured after treatment of cultural practices (Tillering after harvest and before transplanting, stalk and root destruction, early transplanting early removal of the mulching film) and soil fumigation(Cylon).