• Journal of The Korean Association For Science Education
• /
• v.24 no.5
• /
• pp.937-945
• /
• 2004

In this study, we examined high school students' abilities for solving problems under single concept situations and complex concept situations and their mental capacities. Single concept situations are defined as the problems which can be solved with a scientific concept or principle and complex concept situations are the problems combined with more than 2 single concept situations. 152 11th-graders were participated in this study, who had taken natural science track. FIT 752 was used to measure their mental capacities. And an instrument, made up of six questions under three single concept situations and three complex concept situations, was used to assess students' problem solving abilities. As results, students' problem solving abilities were lower in complex concept situations than in single concept situations. There wasn't significant difference in mental capacities between of students who succeeded in solving problems and ones who did not under both single and complex concept situations. Although students solved the problems of single concept situations, some of them failed in solving the problems of complex concept situations composed of single concept situations which they succeeded in solving. They belonged to relatively low mental capacity group, of which students who failed in solving problems of complex situations had lower metal capacities than ones who succeeded in solving them. According to these results, it could be concluded that mental capacity is one of main variables which have influence on problem solving of complex concept situations composed of solvable single concept situations.

• Proceedings of the KSR Conference
• /
• 2007.11a
• /
• pp.371-376
• /
• 2007

This paper describes a study to determine proper escape way interval for the design phase of single bored double track tunnel. Among many methods which determine escape way interval, we choose a QRA(Quantitative Risk Analysis) method. But a different method must be chosen differ from other country because of special design situation of Korea. So, it is necessary to develop a method which considers a special design condition of Korea. Because fire accidents of railway tunnel are a rare event, simulated situation can be produced by CFD simulation and evacuation analysis simulation. However, it is generally difficult to estimate of fatalities from these methods, so a concept of FED is introduced to estimate of fatalities. Quantification process provides effective results for practical design stage and the result were employed in design.

• Journal of applied mathematics & informatics
• /
• v.41 no.5
• /
• pp.973-988
• /
• 2023

In real-life scenarios, we may have to deal with real numbers or numbers in intervals or a combination of both to solve multi-criteria decision-making (MCDM) problems. Also, we may come across a situation where we must combine this interval and actual number membership values into a single real number. The most significant factor in combining these membership values into a single value is by using aggregation operators or scoring algorithms. To overcome such a situation, we suggest the cubic hypersoft set (CHSS) concept as a workaround. Ultimately, this makes it simple for the decision-maker to obtain information without misconceptions. The primary aim of this study is to establish some operational laws for the cubic hypersoft set, present the fundamental properties of aggregation operators and propose an algorithm by using the technique of order of preference by similarity to the ideal solution (TOPSIS) technique based on correlation coefficients to analyze the stress-coping skills of workers.

• Cross-Cultural Studies
• /
• v.27
• /
• pp.471-496
• /
• 2012

Since Takeo Toi's discussion in The Anatomy of Dependence (1973), the concept of amae has generated considerable interest in the fields of psychology, anthropology, communication and other fields. However, there have been few agreements on the definition and functions of amae (Behrens, 2004). Furthermore, it has rarely drawn interest from linguists in general and has rarely been discussed in the context of social interaction. This study aims to examine the concept of amae in Japanese and the corresponding phenomena in Korean, and attempts to explore the similarities and differences between them. The prototype of the amae relationship is the mother-infant relationship (Doi,1973). Even an adult can assume the role of a baby, showing his or her need for dependence on others and expecting to be accepted. It turns out that amae-like phenomena frequently occur in everyday life in Korea as well (Lee, 1982). There is no single term for the concept, but it can be translated in many different ways in Korean, for example, aykyo, ayang, ungsek, erikwang, etc. It can have either positive or negative connotations depending on the situation. It seems that the psychological system that causes dependent behaviors such as ungsek in Korea is cheong, one of the key terms characterizing the Korean culture. Cheong, like amae, starts in the mother-infant relationship extending to familial and to other relationships. A corpus-based analysis shows that cheong is conceptualized as gluing people together, growing over time, and also potentially fatal because it assumes illogical, uncalculated, and personal relationships. In conclusion, unlike some Japanese scholars' claim that amae is the Japanese concept that exists only in Japan, it seems that similar phenomena do exist in Korea as well, but that Korean has no single term corresponding to amae in Japanese. It seems that cheong can be posited in Korean as the inner emotional system that makes amae-like behaviors possible, and that there is not single term, but many, designating the behaviors, possibly because the behaviors have a negative connotation and are not encouraged in Korean society.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.46 no.spc
• /
• pp.39-53
• /
• 2023

Recently, the market competition has been fiercer due to the acceleration of technological change and the launch of intelligent products. In this situation, technology cooperation activities through networks rather than independent technological innovation activities of a single company or institution are recognized as a crucial strategy to gain competitiveness. Technology cooperation can take various forms depending on the target technology, and researchers have conducted performance analyses of technology cooperation types. However, there have not been data-based quantitative studies on the types and trends of technology cooperation for the target technology. In this paper, we explored the difference between the technology cooperation types by technology and time using the formal concept analysis method and co-patent information. In particular, the proposed methodology has been verified through the case study of electric vehicles, and it is intended to suggest the direction of technological cooperation according to specific technologies and cooperation targets in the future

• Journal of Korean Institute of Industrial Engineers
• /
• v.23 no.1
• /
• pp.129-146
• /
• 1997

In traditional approaches to scheduling problems, a single dispatching rule was used by all machines in a system. However, since the situation of each machine generally differs from those of other machines, it is reasonable to apply a different dispatching rule to each machine responding to its given situation. In this regard, we introduce the concept of spatial adaptation and examine its effectiveness by simulation. In the spatial adaptation, each machine in a system selects an appropriate dispatching rule in order to improve productivity while it strives to be in harmony with other machines. This study proposes an adaptive procedure which produces a reliable dispatching rule for each machine beginning with the bottleneck machine. The dispatching rule is composed of several criteria of which priorities are adaptively weighted. The weights are learned for each machine through systematic simulations. The simulations are conducted according to a Taguchi experimental design in order to find appropriate sets of criteria weights in an efficient and robust way in the context of environmental variations. The proposed method was evaluated in an application to a semiconductor wafer fabrication system. The method achieved reliable performance compared to traditional dispatching rules, and the performance quickly approached the peak after learning for only a few bottleneck machines.

• Journal for History of Mathematics
• /
• v.25 no.3
• /
• pp.53-75
• /
• 2012

When imaginary numbers were first encountered in the 16th century, mathematicians were able to calculate the imaginary numbers the same as they are today. However, it required 200 years to mathematically acknowledge the existence of imaginary numbers. The new mathematical situation that arose with a development in mathematics required a harmony of real numbers and imaginary numbers. As a result, the concept of complex number became clear. A history behind the development of complex numbers involved a process of determining a comprehensive perspective that ties real numbers and imaginary numbers in a single category, complex numbers. This came after a resolution of conflict between real numbers and imaginary numbers. This study identified the new perspective and way of mathematical thinking emerging from resolving the conflicts. Also educational implications of the analysis were discussed.

• Journal for History of Mathematics
• /
• v.27 no.1
• /
• pp.67-79
• /
• 2014

When imaginary numbers were first encountered in the 16th century, mathematicians were able to calculate the imaginary numbers the same as they are today. However, it required 200 years to mathematically acknowledge the existence of imaginary numbers. The new mathematical situation that arose with a development in mathematics required a harmony of real numbers and imaginary numbers. As a result, the concept of complex number became clear. A history behind the development of complex numbers involved a process of determining a comprehensive perspective that ties real numbers and imaginary numbers in a single category, complex numbers. This came after a resolution of conflict between real numbers and imaginary numbers. This study identified the new perspective and way of mathematical thinking emerging from resolving the conflicts. Also educational implications of the analysis were discussed.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2004.03a
• /
• pp.601-604
• /
• 2004

Precise position and attitude control of pico-satellite requires huge number of impulses of the order of 10$^{-6}$ Ns. MEMS solid rocket array is a promising propulsion system but the higher degree of miniaturization causes unreliable operation mainly due to quenching. In order to breakthrough this situation, a novel design of solid micro-rocket is proposed, which generates tiny impulses repetitively from a single rocket not from array. This unique micro-rocket is based on the utilization of quenching, which causes propellant reaction to sustain only in a small area. A test chip of a micro solid propellant tank and micro heater array is fabricated and ignition test is conducted. Obtained results show the feasibility of this concept and future direction of this quenching-based propulsion is discussed.

• Journal of Power Electronics
• /
• v.14 no.6
• /
• pp.1166-1177
• /
• 2014

A new type of topology with medium-frequency-transformer (MFT) isolation for medium voltage wind power generation systems is proposed in this paper. This type of converter is a high density power conversion system, with high performance features suitable for next generation wind power systems in either on-shore or off-shore applications. The proposed topology employs single-phase cascaded multi-level AC-AC converters on the grid side and three phase matrix converters on the generator side, which are interfaced by medium frequency transformers. This avoids DC-Link electrolytic capacitors and/or resonant L-C components in the power flow path thereby improving the power density and system reliability. Several configurations are given to fit different applications. The modulation and control strategy has been detailed. As two important part of the whole system, a novel single phase AC-AC converter topology with its reliable six-step switching technique and a novel symmetrical 11-segment modulation strategy for two stage matrix converter (TSMC) is proposed at the special situation of medium frequency chopping. The validity of the proposed concept has been verified by simulation results and experiment waveforms from a scaled down laboratory prototype.