• Fashion & Textile Research Journal
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• v.24 no.6
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• pp.667-685
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• 2022

This paper aims to investigate 4D printing materials for soft robots. 4D printing is a targeted evolution of the 3D printed structure in shape, property, and functionality. It is capable of self-assembly, multi-functionality, and self-repair. In addition, it is time-dependent, printer-independent, and predictable. The shape-shifting behaviors considered in 4D printing include folding, bending, twisting, linear or nonlinear expansion/contraction, surface curling, and generating surface topographical features. The shapes can shift from 1D to 1D, 1D to 2D, 2D to 2D, 1D to 3D, 2D to 3D, and 3D to 3D. In the 4D printing auxetic structure, the kinetiX is a cellular-based material design composed of rigid plates and elastic hinges. In pneumatic auxetics based on the kirigami structure, an inverse optimization method for designing and fabricating morphs three-dimensional shapes out of patterns laid out flat. When 4D printing material is molded into a deformable 3D structure, it can be applied to the exoskeleton material of soft robots such as upper and lower limbs, fingers, hands, toes, and feet. Research on 4D printing materials for soft robots is essential in developing smart clothing for healthcare in the textile and fashion industry.

• Journal of the korean academy of Pediatric Dentistry
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• v.50 no.2
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• pp.205-216
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• 2023

This study aimed to compare the color stability and surface roughness of three-dimensional (3D) printing resin according to polishing methods. 3D-printed resin specimens were fabricated at TC-80DP (Graphy, Seoul, Korea) with a stereolithography 3D printer, and the specimens were divided into three groups, each of which was not polished, was polished using Enhance^®, and was polished using a Sof-Lex^TM disc. The CIE L^*a^*b^* value and the surface roughness of each group were measured and immersed in artificial saliva and orange juice after 0, 1, 7, 30, and 60 days, and the color difference (ΔE^*) was calculated. As a result of the study, no noticeable color change was observed in artificial saliva, but a noticeable color change was demonstrated in orange juice after 60 days of immersion, and the difference was significant. In the Sof-Lex^TM group, surface roughness according to the solution was found to be significantly higher in the orange juice than that in artificial saliva. No significant difference in color change was found according to the polishing method, but surface roughness was significantly lower in the Sof-Lex^TM group than both that of the unpolished group and that of the Enhance^® group. Nevertheless, all groups exhibited clinically acceptable properties regardless of their higher surface roughness than the threshold for plaque accumulation. Overall, this study recommends utilizing Sof-Lex^TM for polishing 3D printing resin when used in primary anterior tooth coverage.

• Korean Journal of Communication Studies
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• v.18 no.1
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• pp.195-222
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• 2010

This study is aimed at examining the degree in message recognitions with respect to the same global brand Ad. campaign intended for local consumers in Korea, China, and United-States, and applying the results to the forseeable message production of global Ad. campaigns. For this purpose, we conducted a survey by providing those consumers with Anycall Ads. of Samsung mobile phones, which were inserted in local printed advertisements. We concluded that the cultural and environmental differences of markets represent different degrees in message recognitions among these three countries. This result suggests that the localization based on local cultures and market situations is more important than the general standardization in the future global brand Ad. campaigns.

• The Journal of Korean Academy of Prosthodontics
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• v.61 no.4
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• pp.257-267
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• 2023

Purpose. The purpose of the study was to fabricate a prototype robotic simulator for dental education, to test whether it could simulate mandibular movements, and to assess the possibility of the stimulator responding to stimuli during dental practice. Materials and methods. A virtual simulator model was developed based on segmentation of the hard tissues using cone-beam computed tomography (CBCT) data. The simulator frame was 3D printed using polylactic acid (PLA) material, and dentiforms and silicone face skin were also inserted. Servo actuators were used to control the movements of the simulator, and the simulator's response to dental stimuli was created by pressure and water level sensors. A water level test was performed to determine the specific threshold of the water level sensor. The mandibular movements and mandibular range of motion of the simulator were tested through computer simulation and the actual model. Results. The prototype robotic simulator consisted of an operational unit, an upper body with an electric device, a head with a temporomandibular joint (TMJ) and dentiforms. The TMJ of the simulator was capable of driving two degrees of freedom, implementing rotational and translational movements. In the water level test, the specific threshold of the water level sensor was 10.35 ml. The mandibular range of motion of the simulator was 50 mm in both computer simulation and the actual model. Conclusion. Although further advancements are still required to improve its efficiency and stability, the upper-body prototype simulator has the potential to be useful in dental practice education.

• Cartoon and Animation Studies
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• s.40
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• pp.211-242
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• 2015

Recently, the shrunk influence of printed cartoon has been superseded by the influence of Webtoon in the comic industry. Webtoon has gained popularity and interest by being served on internet quickly and easily. Their novel material and sympathetic topic have made it possible for many Webtoons to be reproduced into tv dramas and movies, so, the influence of them has been increased as the copyright industry of culture contents industry. The increasing interest for Webtoon has induced academic studies for the subject. Among the various studies in need on Webtoon, the most important study topics in need are 'Story' and 'Quality' which are criterion for readers to choose Webtoons to read. To create the Webtoon that are great at 'Story' and 'Quality', the study on plots should be preceded, which recast episodes organically through a logical causal relationship. Therefore, in this study, the plots of Webtoons have been analyzed through Rescue plot in and the Riddle plot in selected from the Kang Full's Webtoon series, 'mystery psychology horror season', which are evaluated as the great work at 'Story' and 'Quality.' The analysis was implemented based on Tobias' theory which suggests 'the characteristics of plot' and '8 principles for good plot.' First, Kang Full's webtoons were analyzed through 'the characteristics of plot' and '6 principles for good plot' which is modified from '8 principles of good plot' based on Tobias' theory. Applicability was checked if Tobias' theory could be applied to Kang Full's Webtoon checking through the scenes and contents of the Webtoon. (1) Tobias' 'the characteristics of plot' could be applied to both Rescue plot in and the Riddle plot in . (2) Among '6 principles for good plot', 5 principles are shown in The Lighting Store and all of the 6 principles in Neighbor. The result shows that Tobias theory could be applied to the plot of Webtoon. The fact that Kang Full's Webtoons are composed in a formulaic form could be identified through 'the characteristics of plot' and '6 principles for good plot' shown in Rescue plot in and the Riddle plot in .

• Clean Technology
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• v.19 no.3
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• pp.219-225
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• 2013

Environment-friendly and surfactant-free aqueous cleaning agents have been developed in order to solve various problems generated by surfactants in the aqueous cleaning agents. Aqueous surfactant-free cleaning agents, S-1 and S-2 have been formulated with water-soluble solvents such as propylene glycol and propylene glycol ether on their main components and with some additives. These solvents were chosen because of their good solubility in water and excellent solubility of fluxes which are major contaminants of printed circuit board in the electronic industry. Physical properties of the formulated and the imported cleaning agents were measured to predict their cleaning performance, and their cleaning abilities of flux and solder contaminants were evaluated under the various ultrasonic frequencies by a gravimetric method. The measurement results show that the physical properties of cleaning agent V are generally similar with those of formulated cleaning agents S-1 and S-2. Both the cleaning agent V and the formulated cleaning agents S-1 and S-2 showed similar trends that their pH decrease in the beginning and then increases later on with the increase of their dilution in water. It is considered that the wetting indices of the cleaning agents calculated with experimental values do not not have any influence on their cleaning ability. In ultrasonic cleaning tests under three ultrasonic frequencies of 28, 45, and 100 kHz, their best performances of cleaning solder and flux were obtained at 45 kHz and 28 kHz, respectively, and the cleaning performance of the formulated cleaning agents S-1 and S-2 was better than that of the cleaning agent V. However, in the case of the recommended diluted concentration of 25 wt% cleaning solution, the cleaning performance of the cleaner V for solder and flux was better in the initial stage of cleaning compared to the formulated cleaners. And it may be concluded that the formulated cleaning agents S-1 and S-2 can be applied to cleaning of solder and flux in the industry, based on the experimental results in this study.

• Korean Chemical Engineering Research
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• v.54 no.6
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• pp.863-870
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• 2016

We investigated the physical/chemical phenomena that a slow loss of $CO_2$ inventory into sodium after the sodium-$CO_2$ boundary failure in printed circuit heat exchangers (PCHEs), which is considered for the supercritical $CO_2$ Brayton cycle power conversion system of a sodium-cooled fast reactor (SFR). The first phenomenon is plugging inside narrow sodium channels by micro cracks and the other one is damage propagation referred to as wastage combined with the corrosion/erosion effect. Experimental results of plugging shows that sodium flow immediately stopped as $CO_2$ was injected through the nozzle at $300{\sim}400^{\circ}C$ in 3 mmID sodium channels, whereas sodium flow stopped about 60 min after $CO_2$ injection in 5 mmID sodium channels. These results imply that if pressure boundary of sodium-$CO_2$ fails a narrow sodium channel would be plugged by reaction products in a short time whereas a relatively wider sodium channel would be plugged with higher concentration of reaction products. Wastage by the erosion effect of $CO_2$ (200~250 bar) hardly occurred regardless of the kinds of materials (stainless steel 316, Inconel 600, and 9Cr-1Mo steel), temperature ($400{\sim}500^{\circ}C$), or the diameter of the $CO_2$ nozzle (0.2~0.8 mm). Velocities at the $CO_2$ nozzle were specified as Mach 0.4~0.7. Our experimental results are expected to be used for determining the design parameters of PCHEs for their safeties.

• Hwankyungkyoyuk
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• v.7 no.1
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• pp.46-87
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• 1994

Our country has been consuming a huge amount of energy in the course of industrialization and its demand is expected to increase enormously in the future. However, the deposits of energy resources are so limited that the settlement of energy problem comes up the essential subject. To solve the energy problem, it is requested that new resources to gain energy stably should be developed and also energy should be economized and used effectively. The effective use of energy and an the wisdom of economy in energy are requested to everybody and these things should be habitualized from very young age through education. Nevertheless, almost every school in our country hasn’t been concerned about energy education. Even though they have a concern, they are very short of the energy education materials and the quality of the materials is not so good. Therefore it is very meaningful to the settlement of energy problem of the country to make the students who will lead our country to make the students who will lead our country in the future realize the seriousness of energy problem and to provide them the necessary knowledge and methods to solve this problem so that they practice those things in everyday life. Having these necessities, this research, supported by The Korea Energy Management Corporation(KEMCO), was performed for 8 months from April 17, 1994 to December 17, 1994. Many peoples participated in this study such as 30 staffs of researchers and authors, 5 staffs of photographers and illustrators, and 3 VCR program producers developing an energy education material set for middle school students that includes a printed material for student, a diskette for computer simulation, a teacher's guidebook, VCR material and its guidebook. The following main development direction was established : First, the material for student should be consisted of units that let students know the seriousness of energy problem. Second, the focus should be put on the necessary method and practice to economize energy actually in real life based on the basic knowledge learned in elementary school. Third, material for student should be consisted of modules to be student activity-oriented teaching-learning rather than lecture-oriented one. The activity, to maximize student's interests, should be presented in various forms such as experiments, investigation, play, data interpretation, computer simulation, visits, expression and appreciation, etc. To develop the energy education materials for middle school students, a research plan was made first. After literature review about domestic and foreign energy education materials, several research trips home and abroad, and discussion meetings, the basic theory of energy education such as the principle, objective, contents, teaching-learning method, and evaluation method was established. Material for student was developed through the following procedures : The activities in the existing energy education materials were analysed and were divided into four categories related to energy using places of home, school, community, and country, and which were again divided into three categories related to time of past, present, and future, Considering these division, nine modules which are structure units of material for student were chosen, Each module comprises 2-4 activities. Totally 31 activities were designed in this way. The syllabi were made out for each activity and writing was asked for to experts related to each activity after several discussions and revision. To complement the draft, another several discussions and revision were also made on it and then pictures and illustrations were asked for. All these procedures complete the material for student, titled ; Energy Inquiry of Middle School Students', which totals 129 pages and is all in color. As the manuscript of material for student was fixed, writing for teacher's guidebook was asked for to the same writers. The draft of teacher's guidebook was also complemented through the several concentrated works and discussions. Teacher's guidebook focused on the teaching-learning principle and methods of energy education and on the concrete instruction cases for effective instruction of material for student. It is organized with two parts : the one is 'general outline' which introduces theoretical contents and the other is 'details' which are practically helpful to teaching-learning. It is totally 131 pages including both 'general outline' and 'details'. The VCR material and its guidebook consist of contents that cultivate the good attitude trying to economize energy and raise student's interests with a purpose of strong motivation to recognize the necessity of economy and practice it. After establishing development direction of VCR material through discussion meetings and research trips, its script was made by relevant experts. Then the script was also reviewed two times. The drafted VCR material made by a video material developing expert was examined and modified by previews twice. After completion of VCR material, the VCR guidebook was made. All these procedures led to the development of VCR material which runs 20 minutes in VHS type. The VCR guidebook shows a production purpose of the program, structure of contents, evaluation methods, and contents of the program in detail to give help to instructors when they use this VCR material, When these energy education materials are used, it is desirable that the VCR material should be presented first to induce student's motive, and then material for student is introduced Since the material for student is composed of activity-oriented modules and each module is independent one another in general, and each activity is, too. the necessary module or activity can be chosen and utilized in any order according to school or class conditions. This energy education materials will contribute to the development of student's ability to solve energy problem in everyday life and teacher's ability to teach the fundamental knowledge and method in solving energy problem.

• Cartoon and Animation Studies
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• s.45
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• pp.321-343
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• 2016

The purpose of this thesis is to look through the political and social background of China preparing for a new era after getting out of the Communist Party of Mao Zedong, rapid inflow of the Western modernism and the avant-garde art arising in China with the focus of art works of Xu Bing, which contributed to the expansion of printmaking of China. Particularly, 85 New Wave Movement arose by young artists since 1985 and the China/Avant-Garde Exhibition held in Beijing in 1989 are the two important issues which reflect a new change from the traditional Chinese art. The artists of 85 New Wave Movement, who pursued a historical revolution and novelty, worked very actively by leading private exhibitions. Since the Cultural Revolution, the government owned the National Museum of Fine Art Beijing had exhibitions on a large scale displaying various visual arts such as performing art, installation, painting, sculpture but the Chinese government interrupted exhibitions two time due to bold performing art and unconcealed installation. Some artists were even taken to the police when performing art. Under these circumstances, Xu Bing, who majored printmaking, produced one of his major works, Books from the sky(1988), while he was working on various experiments focusing on the production process of printmaking and its repetitiveness. Xu Bing devised letters, carved them in trees and finally created approximately 2000 characters. Going further he displayed it as installation work, which means the developed characters go beyond a printed form, for audiences. This made him earn favorable reviews since it was a form of western art coupled with Chinese contents 'Chinese character'. After he received unfavorable reviews, however, he went to America leaving his last work in China, Ghost Pounding the Wall, in 1990, which was not able to exhibited. In those days, China society was going through a chaotic era thanks to the extinction of the Cultural Revolution and Deng Xiaoping's(1904-1997) reformation after the debacle of Tiananmen Massacre. This study looks into Xu Bing's artworks from his initial print works until he went to the US in 1991 and examines how he performed experiments utilizing reproductivity and plurality of prints tinged with Chinese traditional elements, and ultimately became one of the avant-garde artists representing the period.

• Health Policy and Management
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• v.8 no.2
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• pp.125-148
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• 1998

Accurate vital statistics are essential for a national health planning and evaluation. Among various vital statistics, birth and death rates, and infant and matemal mortality rates together with the causes of death are the very basic ones for above purposes as well as for the maternal and child health management. These statistics are based on the birth and death reports. It is required by law to report every birth and death within one month after its occurrence. However, in case of a neonatal death occurring prior to the birth report, most of the birth and death are not reported. Thus accurate infant and maternal mortality rates are not available yet in Korea. The main objective of this study is to develop a birth and infant death reporting system via computer network. We designed a new birth report form based on the current form and data from the analysis of medical record forms of 14 hospitals. A new form is basically addition of essential medical information to the current birth report form. Since a revision of the rules and regulations related wtih the birth report is necessary to use a new form, we kept the current from intact to make it acceptable to the government office for a field trial. We also developed computer programs for data input for birth and death reports at a medical faciltiy, data processing for production of maternal and child health indices at a health center, and management of maternal and child health services including immunization and postantal care at health center. The birth certificate and birth report can be printed out at a medical facility. The computer packages were programmed by Borland Delphi 3.0 and can be run under Windows 95 system. We proposed a new birth and death reporting system via computer network after a field trial for data input, transmission, and processing. The medical and demographic data o birth and death at medical facilities will be sent to health centers directly via computer network. The health center will retain the medical data for analysis and forward only the data for birth and death reports required by current regulations to the Dong, Up, or Myun Office. Once the birth or death is reported via computer network to the Dong Office, then the Dong Office will notify the baby's mother of the birth report and request to submit the baby's name by mail. When the baby's name its submitted. the Dong Office will forward the birth reports to the Common Court and Statistics Agency in the same way as the current system, Upon the completion of birth registration of the Common Court, the court will issue the birth certificate to mother which will be used in lieu of the family record. The advantages of proposed birth and death reporting system via computer network ar as follows ; I) The accuracy, timing, and completeness of reporting will be improved and more accurate maternal and child health indices can be obtained, ii) The maternal and child health services of health center will be obtained, iii) Epidemiologic data for pregnancy and birth can be obtained, iv) Manpower for birth and death reporting will be saved.