• Bulletin of the Korean Mathematical Society
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• v.58 no.1
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• pp.171-181
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• 2021

The fixing number of a graph G is the smallest order of a subset S of its vertex set V (G) such that the stabilizer of S in G, ��S(G) is trivial. Let G1 and G2 be the disjoint copies of a graph G, and let g : V (G1) → V (G2) be a function. A functigraph FG consists of the vertex set V (G1) ∪ V (G2) and the edge set E(G1) ∪ E(G2) ∪ {uv : v = g(u)}. In this paper, we study the behavior of fixing number in passing from G to FG and find its sharp lower and upper bounds. We also study the fixing number of functigraphs of some well known families of graphs like complete graphs, trees and join graphs.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.42 no.3
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• pp.1-6
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• 2010

A new testing method named pitch deposit tester (PDT) was developed by KRICT in order to evaluate the deposit potential of micro-stickies. The new method involves depositing the potential pitch particles on the air bubble covered plastic film set in the pitch deposit tester (PDT) and analysing the deposited area by an image analyzer. In this study, the effect of fixing agents on potential pitch deposition was elucidated. The effects of some fixing agents (polyamine and polyethyleneimine) on pitch control were investigated by the PDT test of 100% recycled newsprint stock. The study suggested that proper use of the PEI can lead to better pitch control than that of polyamine. The efficiency of novel screening method using the PDT and retention and drainage analyser (RDA) for fixing agents in terms of retention and deposit contamination could be confirmed by above mentioned results.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2000.04a
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• pp.613-616
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• 2000

This paper considers the problem of subway crew scheduling. Crew scheduling is concerned with finding a minimum number of assignments of crews to a given timetable satisfying various restrictions. Traditionally, crew scheduling problem has been formulated as a set covering or set partitioning problem possessing exponentially many variables, but even the LP relaxation of the problem is hard to solve due to the exponential number of variables. In this paper, we propose two basic techniques that solve the problem in a reasonable time, though the optimality of the solution is not guaranteed. To reduce the number of variables, we adopt column-generation technique. We could develop an algorithm that solves column-generation problem in polynomial time. In addition, the integrality of the solution is accomplished by variable-fixing technique. Computational results show column-generation makes the problem of treatable size, and variable fixing enables us to solve LP relaxation in shorter time without a considerable increase in the optimal value. Finally, we were able to obtain an integer optimal solution of a real instance within a reasonable time.

• Journal of the Korean Operations Research and Management Science Society
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• v.27 no.4
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• pp.67-86
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• 2002

This paper considers subway crew scheduling problem. Crew scheduling is concerned with finding a minimum number of assignments of crews to a given timetable satisfying various restrictions. Traditionally, crew scheduling problem has been formulated as a set covering or set partitioning problem possessing exponentially many variables, but even the LP relaxation of the problem is hard to solve due to the exponential number of variables. In this paper. we propose two basic techniques that solve the subway crew scheduling problem in a reasonable time, though the optimality of the solution is not guaranteed. We develop an algorithm that solves the column-generation problem in polynomial time. In addition, the integrality of the solution is accomplished by variable-fixing technique. Computational result for a real instance is reported.

• Korean Journal of Agricultural Science
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• v.31 no.1
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• pp.35-44
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• 2004

In this study, the automatic system exchanging well-plates was developed as a basic stage of the genome project. The developed system consisted of the plate fixing well-plates, the well-plate cassette, the head to move a well-plate from the well-plate cassette to the plate fixing well-plates before genome work or from the plate to the cassette after the work, the manipulator to move the head on the X, Y and Z axes and the control system. The performance test to exchange well-plates with the robotic system developed was carried out. The time to set an well-plate from the well-plate cassette onto the board fixing well-plates was 55 seconds and the time for 9 ones was 8 minutes and 15 seconds. It took 57 seconds to move a well-plate from the board to the cassette and 8 minutes and 33 seconds for 9 ones.

• Korea Journal of Hospital Management
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• v.8 no.1
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• pp.1-23
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• 2003

General drug prices involve three stages: shipment stage, wholesaler stage and retail stage. Policies on drug price differ from country to country. Shipment stage prices are tightly regulated in countries like France and Netherlands. They are free in only a minority of advanced countries, even if these include some major players such as the US, Germany and, in a very limited sense, Japan. The situation in the UK is very complex with a semi-free system, where drug companies are free to set their own prices but cannot exceed a predetermined profit ceiling. Mark-up at both wholesaler and retail stages is formally admitted in most countries observed. Apart from the general drug prices, reimbursement price of insured drugs has been major policy concerns. Most countries reviewed in this study has exerted some control over reimbursement prices, but differ both in the way how and in the extent to which prices are admitted or fixed. Price fixing has been used in France and Japan. Some countries have transformed their system over time, particularly to move to reference pricing in the last decade. This mechanism has empowered the customer, and improved price competition on the market. Referring to the drug price policies in the advanced countries, this study makes some suggestions for the redirection of Korean price policy for reimbursement drug in health insurance as follows: to match appropriate policy tools to each policy goal; to maximize market mechanism through effective reimbursement price fixing which admits mark-ups in wholesaler and retail prices; to introduce reference pricing system in order to redirect patient's demand with a financial incentive to choose the best-priced drugs and to save the finance of health insurance; and to strengthen surveillance and monitoring mechanism in the drug market.

• Management Science and Financial Engineering
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• v.13 no.2
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• pp.1-27
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• 2007

This paper presents a fuzzy-goal programming(FGP) approach for Bi-Level Linear Multiple Objective Decision Making(BLL-MODM) problem in a large hierarchical decision making and planning organization. The proposed approach combines the attractive features of both fuzzy set theory and goal programming(GP) for MODM problem. The GP problem has been developed by fixing the weights and aspiration levels for generating pareto-optimal(satisfactory) solution at each level for BLL-MODM problem. The higher level decision maker(HLDM) provides the preferred values of decision vector under his control and bounds of his objective function to direct the lower level decision maker(LLDM) to search for his solution in the right direction. Illustrative numerical example is provided to demonstrate the proposed approach.

• Cartoon and Animation Studies
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• s.25
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• pp.87-108
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• 2011

Published comics are widely recognized as a popularity-gaining media as well as Soap opera and the movies, and it also has a established characteristic of category. However, compare to the multimedia such as the movies, soap opera and playes, the research on direction is not yet satisfactory This research mainly tries to investigate on, first, whether the theoretically classified functions do actually practice their parts or not, and else, what other additional functions should be considered, by classifying the set up of basic direction functions, angles and range, which the most-cited angle and distance notion of 'Ahn Su Cheol' in comic education field. First, although we tried to approach with the expectation of angle and distance set up that will have a high frequency of certain set ups according to the atmospheres of comics of genre, unlike the expectation, they are rather displayed depending on the personal taste of the writers. The functional aspects of angles and distance set up are the fixing that are only limited in the space of representation, and it is the set up of physical space that should come first as the function of expressing the intensity. As we investigate the characteristics of comic direction, this research will help the range of comic direction to be broadened.

• Journal of architectural history
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• v.14 no.2 s.42
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• pp.143-157
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• 2005

This study aims to analyze functions and characteristics of 'Cha-il(遮日)' which was used at ritual events(宮中儀禮行事) in the Joseon dynasty, Joseon dynasty had many ritual events related with O-Rae(五禮). Cha-il was almost used at important ritual events, especially at the congratulatory events. The congratulatory events(宮中宴享) are the representative events were held with many temporary install facilities(假設施設) in a palace. Cha-il was a kind of Korean traditional membrane structures. Cha-il was set up for cutting off interior space from sunlight and rain. In general, Cha-il was Consisted of Cha-il-jang(遮日帳:woven fabric), Cha-il-jook(遮日竹:bamboo column), some ropes, and fixing wares. In the congratulatory events, three types of Cha-il. were set up. Baek-mok-Dae-Cha-il(白木大遮日)was made of cotton cloth. Yu-Dun-Cha-Il(油芚遮日) was made of oiled paper or oiled cotton cloth. Man-Joen-Cha-Il(滿箭遮日) consisted of wooden structure. Baek-mok-Dae-Cha-il(白木大遮日)was set up on the most important area of stage for protecting from sunlight. Yu-Dun-Cha-Il was set up on less important area of stage for protecting from sunlight and rain. Man-Joen-Cha-Il was set up below Baek-mok-Dae-Cha-il for supporting and draining raindrops off. The results of this study were as follows; Functions of Cha-il were to protect ritually space from sunlight and rain, and to extend ritually space, and to reconstruct ritually space. Cha-il was the peculiar temporary install facility which differed from other countries.

• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.697-700
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• 2005

Aquifer Thermal Energy Storage (ATES) system can be very cost-effective and renewable energy sources, depending on site-specific parameters and load characteristics. In order to develop an ATES system which has certain hydrogeological characteristics, understanding of the thermo hydraulic processes of an aquifer is necessary for a proper design of an aquifer heat storage system under given conditions. The thermo hydraulic transfer for heat storage is simulated using FEFLOW according to two sets of pumping and waste water reinjection scenarios of heat pump operation in a two layered confined aquifer. In the first set of model, the movement of the thermal front and groundwater level are simulated by changing the locations of injection and pumping well in seasonal cycle. However, in the second set of model the simulation is performed in the state of fixing the locations of pumping and injection well. After 365 days simulation period, the temperature distribution is dominated by injected water temperature and the distance from injection well. The small temperature change is appears on the surface compared to other slices of depth because the first layer has very low porosity and the transfer of thermal energy are sensitive at the porosity of each layer. The groundwater levels and temperature changes in injection and pumping wells are monitored to validate the effectiveness of the used heat pump operation method and the thermal interference between wells is analyzed.