• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.2
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• pp.719-725
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• 2017

Frozen milk products are commonly made in small refrigeration machines. R-502 has long been used as a refrigerant for soft ice cream machines, but it is being replaced with R-404A due to the issue of ozone layer depletion. However, R-404A has high global warming potential, so it also needs to be replaced. In this study, a mixture of R-290 and R-32 was considered as a new refrigerant. An optimization and performance evaluation of the mixture were conducted for a freezer volume of 2.8 liters. The focus of the optimization was the appropriate refrigerant charge and the opening of the expansion valve. At the optimized conditions, ice cream was produced in 6 minutes and 24 seconds with the mixture, and the COP was 0.83. For R-404A, the ice cream production time was 6 minutes and 22 seconds, and the COP was 0.90. The results may be used for the design of food refrigeration machines and to optimize other refrigeration cycles.

• Journal of the Korean Society of Marine Environment & Safety
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• v.26 no.5
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• pp.569-575
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• 2020

In this study, a fuel cell system model for ship power was developed and verified by comparing the experimental results obtained by supplying pure oxygen. To verify the proposed model, the fuel cell output characteristics when oxygen was supplied were compared with those when air was supplied using an air compressor. In addition, the effect of the change in the thermal properties of the fuel cell system on the output of the stack was examined. Within the experimental range of this study, when pure oxygen was supplied as the cathode supply gas, the calculated and experimental voltages and outputs obtained through modeling were almost the same over the entire load range. When air was supplied instead of oxygen for the cathode supply at a constant load of 560 A, each stack voltage was approximately 14 V, the stack output was approximately 8 kW, and the stack efficiency was approximately 3 %. It was confirmed that the overall system efficiency was reduced by approximately 8 %. Among the thermal properties examined in this study, the heat transfer coefficient of the coolant to the stack was found to have the greatest effect on the output of the stack.

• The Journal of Art Theory & Practice
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• no.6
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• pp.101-121
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• 2008

An artist, Oh Yun(1946~86)'s theory of people's art during his final period is summed up in his essay 'Expansion of Artistic Imagination and World' (1985). Emphasizing the mystic and traditional characteristics of Oh Yun's artistic oeuvre during his final period, some critics focus on Oh Yun's experience of medical treatment and shamanistic custom at Jin Do island, and his belief in Jeung San Do, the dao of Jeung-san, the Ruler of the Universe. However, they forget the practical intention and implication of his theory of art during his final period, which aimed to overcome the contradiction of revelation itself. Oh Yun's essay criticized the loss of artistic imagination and the ignorance of traditional culture that resulted from the elevation of science to a religion, and insisted that the stereotyped idealism, scientism and elitism in art should be overcome in order to recover the full reality in realism and to continue traditional cultures. The essay is comprised of 18 paragraphs. Oh Yun criticized monochromatic art, conceptual art, hyper-realistic art, objet d'art, and neo-dadaist art, saying that they were simply mechanical forms of modern art derived from scientism and a fetishistic lens culture. In addition, he criticized naturalism in art, which had continued as a tendency in the development of western art, for the same reason. He pointed out that even the world of realism had been diminished by elite stereotypes and diagrams. He declared the need to overcome the imitation of shells or stereotyped propaganda, and recover full realism, which seems to have started with a reflective examination of current problems in 'Reality and Utterance', in which he participated. Especially, he thought that universality and the extension of full realism could be achieved by building on the views of traditional cultures, which is meaningful. This logic is same as the theory of epic theatre that Bertolt Brecht(1898~1956) has developed under the ancient Greek masque and Pieter Bruegel the Elder(1525~69)'s story-like picture style. The universality of realism and the extension of acquisition to include incantation art, rather than move toward incantation art, is what Oh Yun intended to propose in 'Artistic Imagination'. This attitude is same as Bertoh Brecht's aesthetic viewpoint in the 1930s. But regrettably, Oh Yun's style wording, which seems covert and far-sighted, is often misunderstood as 'mysticism'. In the flow of people's art in the 1980s, Oh Yun was a traditionalist in a narrow sense, and an realist in a broad sense. However, his critical mind, which comprehends tradition and reality, was attempting to expand universality and extend full realism, and this attempt found many sympathizers and had an influence on the next generation of people's artists, such as "Levee" which is field-centered, to which we should pay attention. This means that while their works thought about 'tradition', we should be careful not to connect them with 'aesthetic conservatism' or 'classical art'. This is the why the meaning of Oh Yun's theory of art during his final period should be closely examined again.

• Journal of Biomedical Engineering Research
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• v.33 no.4
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• pp.184-193
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• 2012

Many studies have reported that housework done using household appliances may affect biomechanical characteristics of the musculoskeletal system. The purpose of this study was to investigate the effects of housework done using a pulsator washing machine on joints and muscles. We calculated joint torques and muscle strengths on the basis of an experimental/virtual three-dimensional motion analysis for six healthy females using the pulsator washing machine at different heights (H) and depths (D) of the inside drum (H (mm){\times}D (mm), Trial1: $962.5{\times}609.4$, Trial2: $962.5{\times}624.4$, Trial3: $982.5{\times}644.4$, Trial4: $995.5{\times}642.4$, Trial5: $1015.5{\times}677.4$). The joint torques and muscle strengths tended to be considerably different during torso flexion in the sagittal plane for all the trials. The maximum joint torques for the thoracic vertebra, left ankle, and right shoulder measured in Trial4 were significantly higher than those measured in the other trials (p < 0.05); in addition, those for the thoracic vertebra and both ankles measured in Trial5 were significantly higher than those measured in the other trials (p < 0.05). The maximum muscle strengths for the left trapezius muscle and both tibialis anterior muscles measured in Trial5 were significantly higher than those measured in the other trials (p < 0.05). These results indicate that housework done using a pulsator washing machine may affect joint torques and muscle strengths, and these effects are dependent on the height and/or depth of the inside drum of the pulsator washing machine.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.5
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• pp.1148-1156
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• 2009

In order to manufacture noodles using rice flour as its main ingredient, organic acid and thickening agents have been used, and protein, dextrin, and refined salt have added. The rice flour dough that had been baked using organic acids and thickening agent showed the max weight of $2040.00\;g/cm^2$, elasticity value of 139.12%, cohesiveness of 66.05%, chewiness of 1,396.13g, and brittleness of 190,456.12g respectively. The appropriate conditions for manufacturing rice noodle using rice flour were that the rice was to be soaked for 12 hours at temperature of $20{\sim}25^{\circ}C$ and to be milled twice at temperature lower than $35^{\circ}C$. Additionally, the most ideal condition to manufacture noodles was to use the rice flour by combining protein, dextrin and refined salt using 3.88% organic acid blend and 2.82% blend of thickening agents in order to change the rice flour properties

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.1
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• pp.688-695
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• 2017

This paper deals with characteristics analysis of a permanent magnet (PM) linear generator using analytical methods for wave energy harvesting. The wave energy is carried out from the movement of a yo-yo system. A linear generator using permanent magnets to generate a magnetic force itself does not require a separate power supply and has the advantage of simple maintenance. In addition to the use of a rare earth, a permanent magnet having a high-energy density can be miniaturized and lightweight, and can obtain high energy-conversion efficiency. We derived magnetic field solutions produced by the permanent magnet and armature reaction based on 2D polar coordinates and magnetic vector potential. Induced voltage is obtained via arbitrary sinusoidal input. In addition, electrical parameters are obtained, such as back-EMF constant, resistance, and self- and mutual-winding inductances. The space harmonic method used in this paper is confirmed by comparing it with finite element method (FEM) results. These facilitate the characterization of the PM-type linear generator and provide a basis for comparative studies, design optimization, and machine dynamic modeling.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.8
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• pp.18-25
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• 2020

With the development of water internet technology, data communication between objects is expanding. Research related to data communication technology between vehicles that incorporates related technologies into vehicles has been actively conducted. For data communication between mobile terminals, data stability, reliability, and real-time performance must be guaranteed. The 5 GHz Wi-Fi band, which is advantageous in bandwidth, communications speed, and wireless saturation of the wireless network, was selected as the data communications network between vehicles. This study analyzes how to design and implement a 5 GHz Wi-Fi network in a vehicle network. Considering the characteristics of the mobile communication terminal device, a continuous variable communications structure is proposed to enable high-speed data switching. We simplify the access point access procedure to reduce the latency between wireless terminals. By limiting the Transmission Control Protocol Internet Protocol (TCP/IP)-based Dynamic Host Configuration Protocol (DHCP) server function and implementing it in a broadcast transmission protocol method, communication delay between terminal devices is improved. Compared to the general commercial Wi-Fi communication method, the connection operation and response speed have been improved by five seconds or more. Utilizing this method can be applied to various types of event data communication between vehicles. It can also be extended to wireless data-based intelligent road networks and systems for autonomous driving.

• Journal of Korean Neurosurgical Society
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• v.63 no.2
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• pp.137-152
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• 2020

In spite of the developing endovascular era, large (15-25 mm) and giant (>25 mm) wide-neck cerebral aneurysms remained technically challenging. Intracranial flow-diverting stents (FDS) were developed to address these challenges by targeting aneurysm hemodynamics to promote aneurysm occlusion. In 2011, the first FDS approved for use in the United States market. Shortly thereafter, the Pipeline of Uncoilable or Failed Aneurysms (PUFS) study was published demonstrating high efficacy and a similar complication profile to other intracranial stents. The initial FDA instructions for use (IFU) limited its use to patients 22 years old or older with wide-necked large or giant aneurysms of the internal carotid artery (ICA) from the petrous segment to superior hypophyseal artery/ophthalmic segment. Expanded IFU was tested in the Prospective Study on Embolization of Intracranial Aneurysms with PipelineTM Embolization Device (PREMIER) trial. With further post-approval clinical data, the United States FDA expanded the IFU to include patients with small or medium, wide-necked saccular or fusiform aneurysms from the petrous ICA to the ICA terminus. However, IFU is more restrictive in South Korea than in United States. Several systematic reviews and meta-analyses have sought to evaluate the overall efficacy of FDS for the treatment of cerebral aneurysms and consistently identify FDS as an effective technique for the treatment of aneurysms broadly with complication rates similar to other traditional techniques. A growing body of literature has demonstrated high efficacy of FDS for small aneurysms; distal artery aneurysms; non-saccular aneurysms posterior circulation aneurysms and complication rates similar to traditional techniques. In the short interval since the Pipeline Embolization Device was first introduced, FDS has been firmly entrenched as a powerful tool in the endovascular armamentarium. As new FDS are developed, established FDS are refined, and delivery systems are improved the uses for FDS will only expand further. Researchers continue to work to optimize the mechanical characteristics of the FDS themselves, aiming to optimize deploy ability and efficacy. With expanded use for small to medium aneurysms and posterior circulation aneurysms, FDS technology is firmly entrenched as a powerful tool to treat challenging aneurysms, both primarily and as an adjunct to coil embolization. With the aforementioned advances, the ease of FDS deployment will improve and complication rates will be further minimized. This will only further establish FDS deployment as a key strategy in the treatment of cerebral aneurysms.

• Cartoon and Animation Studies
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• s.50
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• pp.1-22
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• 2018

This study investigated realism sceneries shown in animation movies of auteurism. Although animation has properties of mechanical images arranged by short cuts, it essentially starts with the images dealing with space art based on the consciousness of an author. In this aspect, sceneries of animation movies can be the most proper subject for study from the viewpoint of image. Generally, sceneries of animation movies maintain the neutral position as a stage setting for story. However, as for auteurism animation, the sceneries have subjective meaning as major media to express the work or the vision and value of the author on the world. The representative animation movies that reflect the role and meaning of realism sceneries among auteurism animations are and . The former shows Korean sceneries and the latter presents local sceneries of Japan quite well. Reviewing the characteristics of sceneries shown in two movies, the sceneries of are the discovery of internal consciousness of the author that signifies pure innocence of childhood into the voice of nature through the style of the author. Meanwhile, sceneries of adopted nature landscape surrealistically based on the internal consciousness of the author and described the forest as the absolute utopia of the author. As such, the sceneries shown in two movies were utilized as the "framework of thought" of the authors that intensify the viewpoint of the movies on the world through empirical interpretation and detailed description of neutral landscape based on internal consciousness of the authors.

• The Korean Nurse
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• v.37 no.4
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• pp.72-84
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• 1998

This study has been done for the purpose of testing the effects of education for women's health on the performance of health promoting behavior and self esteem of college women. The study was designed as simulated control group pretest-posttest design, the experimental group was composed 182 college women and the control group was composed 151 college women at D University in Seoul. The instruments used for this study were Health Promoting Behavior Scale developed by Walker et al(1987)were modified by Shin(1997) and Self Esteem Scale developed by Rosenberg(1965). The data were analyzed by chi-square test, t-test and ANCOVA using $SPSSIPC^+$ program. The results were as follows: 1. The result of the homogeneity test in terms of the demographic characteristics of two group showed that there were significant difference in major discipline($x^2=155.854$, p=.000), religion($x^2=6.325$, p=.011), and disease experience($x^2=3.949$, p=.046). 2. Hypotheses 1 that the college women who get women's health education will have a higher score of health promoting behavior than the college women who do not get women's health education was supported. The score of health promoting behavior between two group showed statistically difference(t=7.25, p= .000). Mer control of covariates(major discipline, religion, and disease experience), the score of health promoting behavior between two group showed statistically difference(F=31.817, p= .000). 3. Hypotheses 2 that the college women who get women's health education will have a higher score of self esteem than the college women who do not get women's health education was supported. The score of self esteem between two group showed statistically difference(t=4.91, p= .000). After control of covariates(major discipline, religion, disease experience), the score of self esteem between two group showed statistically difference(F=12.688, p= .000). The following suggestions are made based on the above results : 1) Replication of the research is needed to confirm effects of health education including the college man and various demographic differences. 2) More effective health education programs appropriate to subject need to be developed. 3) Nursing college or departments of nursing should make an effort to develop and carry out various health education program for health for all.