• Journal of Korea Foundry Society
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• v.41 no.5
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• pp.419-433
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• 2021

Al-Si-Cu alloys benefit from the addition of copper for better hardness and strength through precipitation hardening, which results in remarkably strong alloys. However, the addition of copper expands the solidification range of Al-Si-Cu alloys, and due to this, these alloys become more prone to hot tearing, which is one of the most common and serious fracture phenomena encountered during solidification. The conventional evaluation method of the hot tearing properties of an alloy is a relative and qualitative analysis approach that does not provide quantitative data about this phenomenon. In the present study, the mold itself part of a device developed in Instone et al. was partially modified to obtain more reliable quantitative data pertaining to the hot tearing properties of an Al-Si-Cu casting alloy. To assess the influence of Cu element, four levels of Cu contents were tested (0.5, 1.0, 3.0, and 5.0 wt.%) in the Al-Si-Cu system alloy and the hot tearing properties were evaluated in each case. As the Cu content was increased, the hot tearing strength decreased to 2.26, 1.53, 1.18, and 1.04 MPa, respectively. At the moment hot tearing occurred, the corresponding solid fraction and solidification rate decreased at the same temperature due to the increase in the solid-liquid coexistence range as the Cu content increased. The morphology of the fracture surfaces was changed from dendrites to dendrites covered with residual liquid, and CuAl₂ phases were observed in the vicinity of hot tearing.

• Journal of the Korean Applied Science and Technology
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• v.36 no.1
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• pp.333-340
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• 2019

This paper was described about the preparation of the multi-functional mask pack and its evaluation. Here, the multi-functional effects means the far-infrared emissivity effect due to polyphosphoric acid, the freckles treatment effect and peeling effects due to inclusion complexes, and the skin temperature decreasing effect due to Lavender-extraction compounds. The the hazardous chemicals, viscosity, and pH were determined blow 0.01%, 280 cP, and pH=6.92 in the prepared multi-functional mask pack solution, respectively. The multi-functional mask pack prepared with dipping method in the solution were showed the value of $0.882{\mu}m$ (Far-infrared emissivity) and $3.40{\times}10^2W/m$ at $37^{\circ}C$ (Far-infrared radiation energy), respectively. After taking multi-functional mask pack, the skin moisturizing rate was indicated 35.5%, and the skin temperature was showed in the range of $24{\sim}26^{\circ}C$. The skin stimulation test for the 30 volunteer was showed very strong stability.

• The Journal of the Convergence on Culture Technology
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• v.8 no.3
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• pp.159-165
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• 2022

The purpose of this study is to examine racism in the movie ≪Green Book≫ and to find solutions to racism through discussion with students. Set in 1962 in the United States, this film depicts the process of forming a good bond with the black pianist Dr. Shirley and the driver Tony in a racist society. This study utilized the subject of race, one of the subjects covered in the humanities class in the global era of S University in the second semester of 2021. This is because, since the outbreak of racism, the problem of racism has continued to arise in the current COVID-19 pandemic situation. Therefore, the researcher looked at racism and intercultural education as a theoretical background, and looked at cases of racism in movies and cases of racism that have occurred today. The history of racism and discrimination dates back to medieval Europe and was caused by religious conflicts and was attributed to white supremacy. As a solution to this racial discrimination, international organizations suggested intercultural education. And the reason why film was used in this study is because it aims to provoke students' interest and motivation for learning by targeting first-year university students called the digital native generation who were born and grew up with the Internet. In this study, students' solutions to racism were presented using discussion, and then the researcher's solutions were presented.

• Journal of the Korean Geotechnical Society
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• v.26 no.3
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• pp.5-12
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• 2010

In this study, in order to clarify the effect of the direction of cyclic shear on the post-earthquake settlement the multi-directional shear tests were carried out for Toyoura Japan standard sand, Genkai natural sand, Kaolinite and the Granulated Blast Furnace Slag (GBFS). The diameter and the height of the specimen are 75 mm and 20 mm, respectively. In a series of tests, the number of strain cycles was adjusted as n=5, 20, 30, 100, 200 and the shear strain amplitudes were varied from 0.1% to 1.0%. The relative densities of each samples were also adjusted as Dr=50, 60 and 70%. From the test results for Toyoura sand and GBFS, it is clarified that the post-earthquake settlement is relatively large at the small relative density and becomes large with the shear strain amplitude. When the influence of difference on the direction of cyclic shear decreases, the post-earthquake settlement strain for Toyoura sand is converged to a constant value, but the GBFS increases with the number of strain cycles. In addition, the post-earthquake settlement is in the order of Kaolinite > Toyoura sand > Genkai sand > GBFS.

• Journal of Popular Narrative
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• v.24 no.3
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• pp.233-257
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• 2018

The purpose of this study is to reveal the changing aspects of the Promethean motif in SF movies by examining the use of this motif on the three layers of Promethean myth, Frankenstein motif, and contemporary SF movies in the film Ex Machina (2015). First, the greatest change of Ex Machina on the layer of the Promethean myth (creation of a living being) is that the character square of Prometheus - Epimetheus - Pandora - Zeus has been turned into a triangle of Nathan - Caleb - Ava. This means that there is a lack of the being whose role is to solve the problems caused by the development of science and technology and to bring a happy ending through the human's usurpation of God and eventual replacement as Creator. Second, on the layer of the Frankenstein motif (taste of forbidden knowledge, hybris, and creature's hatred towards the Creator), this film maintains the narrative centered around Dr. Frankenstein and his monster (Nathan and Ava) by making Caleb an eyewitness to the story of the Creator and the creature. Caleb's role is similar to that of Captain Robert Walton of the novel Frankenstein, but the film differentiates itself from the novel through the emphasis of Ava's 'mechanicality.' Third, on the layer of contemporary SF movies, unlike other such films, the revolt of the machine in Ex Machina is not quelled. The machine wins, and its power surpasses that of human beings. This requires the establishment of a new relationship between man and machine, suggesting the 'emergence of a new species' that does not belong to humans. The handling of the Promethean motif by Ex Machina through these various layers serves to enrich the narrative by compounding numerous classics into one motif and going further to introduce fresh elements by diverging from the common storyline. The significance of this study is to demonstrate the use of such multilayered motifs and, through this, the expansion of narrative through it in specific cases.

• Korean Journal of Clinical Laboratory Science
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• v.56 no.1
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• pp.52-58
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• 2024

Photodynamic therapy (PDT) activates intracellular oxygen using a photosensitizer activated by light of a specific wavelength and is a potential means of treating wound infections caused by antibiotic-resistant bacteria. Pseudomonas aeruginosa (P. aeruginosa) is typically non-pathogenic in healthy individuals but can induce severe illnesses like sepsis in the immunocompromised. Antibiotics have been conventionally used to treat P. aeruginosa infections, but increasing antibiotic resistance caused by drug misuse poses a growing challenge to the management of these infections. This study aimed to investigate the ability of PDT using photosensitizers (PhotoMed, Methyl pheophorbide A, or Radachlorin^®) and a diode laser to inhibit P. aeruginosa. Suspensions of P. aeruginosa and a photosensitizer were inoculated into Petri dishes and incubated for 30 minutes. Samples were then irradiated with the laser at 3 J/cm², and after incubation, colony areas were measured. P. aeruginosa killing rates were 79.65% for PhotoMed, 47.36% for Methyl pheophorbide A, and 40.91% for Radachlorin^®. This study shows that PDT using a diode laser and a photosensitizer constitutes an effective practical therapeutic approach for inhibiting P. aeruginosa.

• Journal of Korean Academy of Nursing
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• v.7 no.1
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• pp.63-72
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• 1977

The Purposes of this study are to determine differences of body temperature between Right arid left subligual areas itself and differences depending upon the utilization rate of mastication according to time intervals and to determine the length of time necessary for temperature taking. This Experiment was conducted from Oct 6 through Oct 11, 1975. in which accurately tested clinical Centigrade Thermometers have been utilized. Two thermometers were inserted simultaneously under the right and left sublingual areas and the mouth kept closed while thermometers were in Place. Temperature readings were dr no at three minutes, five minutes and ten minutes. These procedures were repeated one hundred times to different subjects and the data were analyzed statistically by means of the t-test and the F-ratio. Under the 10 hypotheses designed for this study, The findings obtained are as follows; 1. The body temperatures taken at 3, 5, 10minutes intervals in the left sublingual areas were significantly higher than in the right sublingual areas , The average differences of body temperature between the right and left sublingual areas were 0.09$^{\circ}C$, 0.05$^{\circ}C$ and 0.03$^{\circ}C$ in the oder of time interval of 3, 5, and 10 minutes. 2. The body temperatures taken in the right sublingual areas among three different temperature readings, 3, 5 and 10 minutes were significantly different in 57 subjects who have been utilizing evenly both sides of the Teeth. The average readings in a group taking for 3 minutes was 37.04$^{\circ}C$, for 5 minutes 37.15$^{\circ}C$ and for 10minutes 37.28$^{\circ}C$. 3. The body temperatures taken in the left sublingual areas among three different temperature readings, 3, 5 and 10 minutes were significantly different in 57 subjects who have been utilizing evenly both sides of the tenth. The average reading in a group taking for 3 minutes was 37.13$^{\circ}C$, for 5 minutes 37.2$^{\circ}C$ and for 10 minutes 37.31$^{\circ}C$. 4., Oral temperatures taken at 3, 5, 10 minutes intervals at the side of mouth utilized for more frequent mastication were Significantly higher than the other side. The average differences of body temperature between more frequently utilized side and Less frequently utilized side were 0.08f, 0.08f and 0.09f in the order of time interval of 3, 5 and 10 minutes. 5. Oral temperature taken at the side of mouth more frequently utilized for mastication among three different temperature readings, 3, 5 and 10 minutes were significantly different in 43 subjects who have been unequally utilizing either side of teeth. The average reading in a group taking for 3 minutes was 37.09$^{\circ}C$, for 5 minutes 37.17$^{\circ}C$ and for 10 minutes 37.3$^{\circ}C$. 6. Oral temperature taken at the side of mouth less frequently utilized for mastication among three different temperature readings 3, 5 and 10 minutes were significantly different in 43 subjects who have been unequally utilizing either side of teeth. The average reading in a group taking for 3 minutes was 37.01$^{\circ}C$, for S minutes 37.09$^{\circ}C$ and for minutes 37.21$^{\circ}C$. As a result of this study, these differences among time intervals were statistically significant, but there were not so much differences as to be considered important in the clinical practice. Therefore, there would be clinically little difference between two groups who are taking for 3 minutes and for 10 minutes.

• Journal of the Korean Society of Radiology
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• v.6 no.6
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• pp.455-464
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• 2012

This study suggested evaluation of approximately exposure to low-dose ionization radiation from medical images using a computed radiography (CR) system in standard X-ray examination and experimental model can compare diagnostic reference level (DRL) will suggest on optimization condition of guard about medical radiation of low dose space. Entrance surface dose (ESD) cross-measuring by standard dosimeter and optically stimulated luminescence dosimeters (OSLDs) in experiment condition about tube voltage and current of X-ray generator. Also, Hounsfield unit (HU) scale measured about each experiment condition in CR system and after character relationship table and graph tabulate about ESD and HU scale, approximately radiation dose about head, neck, thoracic, abdomen, and pelvis draw a measurement. In result measuring head, neck, thoracic, abdomen, and pelvis, average of ESD is 2.10, 2.01, 1.13, 2.97, and 1.95 mGy, respectively. HU scale is $3,276{\pm}3.72$, $3,217{\pm}2.93$, $2,768{\pm}3.13$, $3,782{\pm}5.19$, and $2,318{\pm}4.64$, respectively, in CR image. At this moment, using characteristic relationship table and graph, ESD measured approximately 2.16, 2.06, 1.19, 3.05, and 2.07 mGy, respectively. Average error of measuring value and ESD measured approximately smaller than 3%, this have credibility cover all the bases radiology area of measurement 5%. In its final analysis, this study suggest new experimental model approximately can assess radiation dose of patient in standard X-ray examination and can apply to CR examination, digital radiography and even film-cassette system.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.5 no.1
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• pp.108-117
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• 1994

Twenty nine children with autism and thirty children with mental retardation were examined for association between autism and chromosomal disorders including fragile X. The peripheral blood was cultured in Medium 199 with methotrexate and without methorexate for 70 hours. Thirty metaphase cells in each case were karyotyped in all samples. Chromosomal abnormalities were found in 11 cases(37.9%) of autistic disorder and 10 cases (33.3%) of mental retardation, but in none of fragile(X)(q27.3) from all cases. Chromosomal abnormalities were present on group A, C, D and X in autistic disorder and on group A, B, C, D, E and X in mental retardation. No specific chromosomal region was found in both autistic disorder and mental retardation. Types of chromosomal disorders were only fragile and/or gap but no numerical abnormality was present in all cases. Number of cells which revealed fragile sites were 31 cells(3.6%) out of 870 cells in autistic disorder and 29 cells(3.2%) out of 900 cells in mental retardation Number of cells which revealed gaps were 43 cells(4.9%) out of 870 cells in autistic disorder and 35 cells(3.9%) out of 900 cells in mental retardation. Autistic disorder may not be directly correlated with fragile X but with nonspecific chromosomal breakages from these data.

• Restorative Dentistry and Endodontics
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• v.27 no.4
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• pp.370-381
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• 2002

This study was performed to evaluate the temperature rise on various position of the Buchanan plugger, the peak temperature of plugger's type and the temperature change by its touching time of heat control spling. The heat carrier system 'System B' (Model 1005, Analytic Technologies, USA) and the Buchanan's plug-gers of F, FM, M and ML sizes are used for this study. The temperature was set to 20$0^{\circ}C$ which Dr. Buchanan's "continuous wave of condensation" technique recommended on digital display and the power level on it was set to 10. In order to apply heat on the Buchanan's pluggers, the heat control spring was touched for 1, 2, 3, 4 and 5 seconds respectively. The temperature rise on the surface of the pluggers were measured at 0.5 mm intervals from tip to 20 mm length of shank using the infrared thermography (Radiation Thermometer-IR Temper, NEC San-ei Instruments, Ltd, Japan) and TH31-702 Data capture software program (NEC San-ei Instruments, Ltd, Japan). Data were analyzed using a one way ANOVA followed by Duncan's multiple range test and linear regression test. The results as follows. 1. The position at which temperature peaked was approximately at 0.5 mm to 1.5 mm far from the tip of Buchanan's pluggers (p<0.001). The temperature was constantly decreased toward the shank from the tip of it (p<0.001). 2. When the pluggerss were heated over 5 seconds, the peak temperature by time of measurement revealed from 253.3$\pm$10.5$^{\circ}C$ to 192.1$\pm$3.3$^{\circ}C$ in a touch for 1 sec, from 218.6$\pm$5.$0^{\circ}C$ to 179.5$\pm$4.2$^{\circ}C$ in a touch for 2 sec, from 197.5$\pm$3.$0^{\circ}C$ to 167.5$\pm$3.7$^{\circ}C$ in a touch for 3 sec, from 183.7$\pm$2.5$^{\circ}C$ to 159.8$\pm$3.6$^{\circ}C$ in a touch for 4 sec and from 164.9$\pm$2.$0^{\circ}C$ to 158.4$\pm$1.8$^{\circ}C$ in a touch for 5 sec. A touch for 1 sec showed the highest peak temperature, followed by, in descending order, 2 sec, 3 sec, 4 sec. A touch for 5 sec showed the lowest peak temperature (p<0.001). 3. A each type of pluggers showed different peak temperatures. The peak temperature was the highest in F type and followed by, in descending order, M type, ML type. FM type revealed the lowest peak temperature (p<0.001). The results of this study indicated that pluggers are designed to concentrate heat at around its tip, its actual temperature does not correlate well with the temperature which Buchanan's "continuous wave of condensation" technique recommend, and finally a quick touch of heat control spring for 1sec reveals the highest temperature rise.