• Journal for History of Mathematics
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• v.36 no.6
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• pp.105-113
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• 2023

We will suggest a train model to explain the weekly periodic character of Covid19 in South Korea on the first half of 2022, the period of the Omicron variant outbreak. In the model, the daily new infected individuals board a train, divided into 4 compartments. The train moves at night by the length of one compartment. Then the infected are quarantined during the daytime after their compartment reaches the quarantine area. Then it remains empty on the 5-th night after boarding. The parameters of the model are fitted with the daily measured quarantine populations and generate the simulated quarantine populations that hit the real weekly and global peaks.

• Journal of Korean Academy of Nursing
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• v.44 no.5
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• pp.573-580
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• 2014

Purpose: This study was conducted to analyze intubation survival rates according to characteristics and to identify the risk factors affecting deliberate self-extubation. Methods: Data were collected from patients' electronic medical reports from one hospital in B city. Participants were 450 patients with endotracheal intubation being treated in intensive care units. The collected data were analyzed using Kaplan-Meier estimation, Log rank test, and Cox's proportional hazards model. Results: Over 15 months thirty-two (7.1%) of the 450 intubation patients intentionally extubated themselves. The patients who had experienced high level of consciousness, agitation. use of sedative, application of restraints, and day and night shift had significantly lower intubation survival rates. Risk factors for deliberate self-extubation were age (60 years and over), unit (neurological intensive care), level of consciousness (higher), agitation, application of restraints, shift (night), and nurse-to-patient ratio (one nurse caring for two or more patients). Conclusion: Appropriate use of sedative drugs, effective treatment to reduce agitation, sufficient nurse-to-patient ratio, and no restraints for patients should be the focus to diminish the number of deliberate self-extubations.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.221.1-221.1
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• 2012

The Korea Astronomy and Space Science Institute (KASI) is developing three 1.6m optical telescopes with $18k{\times}18k$ mosaic CCD cameras. These telescopes will be installed and operated at Chile, South Africa, and Australia for Korea Micro-lensing Telescope Network (KMTNet) project. The main scientific goal of the project is to discover earth-like extra-solar planets using the gravitational micro-lensing technique. To achieve the goal, each telescope at three sites will continuously monitor the specific region of Galactic bulge with 2.5 minute cadence for five years. Assuming 12 hour observation in maximum for a night, the amount of 200 GB file storage is required for one night observation at one observatory. If we consider the whole project period and the data processing procedure, a few PB class data storage, high-speed network, and high performance computers are essential. In this presentation, we introduce the KMTNet data management plan that handles gigantic data; raw image collecting, image processing, photometry pipeline, database archiving, and backup.

• Journal of English Language & Literature
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• v.54 no.2
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• pp.217-234
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• 2008

Norman Mailer is one of the American writers who dramatize sensual pleasure in order to show how American idealism ends up being trapped and corrupted. The most remarkable cases are the tragic heroes of Scott Fitzgerald and the tough characters of Ernest Hemingway; while the former describes the victim of sensual pleasure, the latter brings the sensuality out from the darkness into 'the clean and well-lighted place.' In one of his most successful experimental fiction writings called 'New Journalism,' Mailer portrays the battle between the liberal left and the conservative right in the demonstration of 1967. Mailer achieves two things in this new technique. First, he demystifies the traditional epistemology grounded in the neutral and transparent narration and suggests that every narration can not escape mediation by a narrator. Secondly, he demonstrates that there is no clear distinction between good and bad. Rather, Good is nothing but a disguised form of Evil, and God is feasible only through the courageous action borrowed from Evil. In this technological world, devil is more powerful and attractive than God. This paper assumes the materiality of courage and focuses on the phenomenology of war carried out not from soul but from body, not from the consciousness but from the materiality.

• Sleep Medicine and Psychophysiology
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• v.6 no.1
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• pp.68-75
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• 1999

Objectives: We intended to observe changes in sleep patterns and mood states of night-shift workers following light exposure. We also estimated the degree of tolerance of light exposure. By studying these, we investigated the possibility of applying light therapy to night-shift workers for improving their adaptation. Methods: Twelve night-shift nurses working at Yong-In Mental Hospital volunteered to participate in this study. The study consisted of 3 parts: 1) night-shift control study; 2) light exposure study; 3) day-shift control study. All the nurses accomplished 3 parts of the study, each of which continued for 3 days, except one nurse who did not participate in day-shift control study. During light exposure study, nurses were exposed to bright light for 4 hours from 1AM to 5AM. Sleep patterns were evaluated with wrist actigraphy and automatic sleep analysis program. Mood states and side effects of light exposure were assessed with self-report scales. Results: Sleep period time, total sleep time, and sleep efficiency were increased following light exposure compared with night-shift control study. Light exposure study showed no difference from day-shift control study in above-mentioned sleep parameters. Daily fluctuation of sleep efficiency was less prominent during light exposure study than during night-shift control study. During light exposure study, the subjects felt more elated and energetic in the evening after daytime sleep than during night-shift control study. None of the subjects complained of severe side effects related to light exposure on the third day of light exposure. Tolerance of side effects was noted to develop with the repetition of light exposure. Conclusion: Light exposure improved the daytime sleep of night-shift workers to the level of normal nighttime sleep, making the subjects more elated and energetic. Side effects of light exposure were found to be tolerable. Light exposure seems to be safely applicable to night-shift workers for their adaptation.

• Journal of Korean Society of Transportation
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• v.33 no.3
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• pp.284-293
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• 2015

The objective of this paper is to determine the conditions of road surface by utilizing the images collected from closed-circuit television (CCTV) cameras installed on roadside. First, a technique was examined to detect wet surfaces at nighttime. From the literature reviews, it was revealed that image processing using polarization is one of the preferred options. However, it is hard to use the polarization characteristics of road surface images at nighttime because of irregular or no light situations. In this study, we proposes a new discriminant for detecting wet and dry road surfaces using CCTV image data at night. To detect the road surface conditions with night vision, we applied the wavelet packet transform for analyzing road surface textures. Additionally, to apply the luminance feature of night CCTV images, we set the intensity histogram based on HSI(Hue Saturation Intensity) color model. With a set of 200 images taken from the field, we constructed a detection criteria hyperplane with SVM (Support Vector Machine). We conducted field tests to verify the detection ability of the wet road surfaces and obtained reliable results. The outcome of this study is also expected to be used for monitoring road surfaces to improve safety.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.13 no.1
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• pp.1-13
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• 1980

The purpose of the present study is to find the light intensity which induces maximum gathering rate and to observe the variation of the gathering rate both in daytime and at night by using three species of commercial fishes: filefish, Stephanolepis cirrhifer (Temminck et Schlegel), conger eel, Astroconger myriaster (Brevoort) and crucian carp, Carassius oarassius (Linnaeus). An experimental tank $(360L\times50W\times55Hcm)$ was set up in a dark room. An illumination system was attached to one end of the tank to control horizontal, light intensity. Six artificial light sources were prepared by combination of two light bulbs (5W, 150W) and seven filters. During the experiment water depth was maintained 50 cm level in the tank. The tank was marked into six longitudinal sections each being 60 cm long to observe the distribution of fish. The fish were acclimatized in dark condition for 40 minutes prior to the main experiment. Upon turning on the light, the number of fish .in each section was counted 40 times every 30 seconds, and the gathering rates were obtain from the average number of fish in each section. In filefish the light intensity inducing maximum gathering rate was 0.7 lx(0.5-1.1 lx), and there nab little difference between day and night. Gathering rate varied propotionally to the length of illumination time. In conger eel the light intensities inducing maximum gathering rate were 1.9 lx(1.2-2.9 lx) in daytime and 5.2 lx (3.2-7.7 lx) at night. Thus, there was a considerable difference between day and night, but the gathering rate remained almost unchanged regardless to the length of illumination time. In crucian carp gathering rate did not show a definite pattern hut fluctuated irregularly. The gathering rate, however, was slightly higher at 16.21 lx, and there was little difference between day and night.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.14 no.2
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• pp.59-65
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• 1981

The purpose of the present study is to find the light intensity which induces maximum gathering rate and to observe the variation of the gathering rate both in daytime and at night by rising two species of commercial fishes: gray rock cod. Sebastes inermis (Cuvier et Valenciennes) and cat shark, Scyliorhinus torazame (Tanaka). An experimental tank $(360L\;{\times}\;50W\;{\times}\;55H\;cm)$ was set up in a dark room. An illumination system was attached to one end of the tank to control horizontal light intensity. Six artificial light sources were prepared by combination of two light bulbs (5W, 150W) and seven filters. During the experiment water depth was maintained 50 cm level in the tank. The tank was marked into six longitudinal sections each being 60 cm long to observe the distribution of fish. The fish were acclimatized in dark condition for 40 minutes prior to the main experiment. Upon turning on the light, the number of fish in each section was counted 40 times every 30 seconds, and the gathering rates were obtain from the average number of fish in each section. The light intensity inducing maximum gathering rate is as follows: gray rock cod: 16.6 lux (10.6-24.5 lux) (day), 0.7 lux (0.5-1.1 lux) (night), cat shark: 1.9 lux (1.2-2.9 lux) (day), 16.6 lux(10.6-24.5lux) (night). Trend of the gathering rate in illumination time revealed different results in two fish species. Gathering rate of gray rock cod did not show any definite pattern but fluctuated irregularly. The gathering rate was some fluctuating at night. However, that of cat shark was almost constant and did not show any distinctive difference between day and night.

• Journal of Bio-Environment Control
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• v.32 no.1
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• pp.15-22
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• 2023

Roses are one of the most produced flower species in the world, and cut roses are produced in the greenhouses all year round. Recently, due to the increase in the temperature in the greenhouses in summer, the quality of cut roses is seriously deteriorated, such as shortening the stem length. This study was conducted to investigate the effects of the growing seasons on the qualities of cut roses and also to test the effect of cooling at night in high temperature season on the cut flower qualities of roses. Comparing the qualities and yields of cut roses for each season, the major cut flower qualities such as flower stem length, stem diameter and fresh weight were statistically significantly decreased in roses ('Pink Beauty' and 'Pink Shine') produced in summer. The yields didn't show a statistically significant difference in both cultivars. Investigating the cut flower qualities, the flower stem length increased by 15% for 'Pink Beauty', 11% for 'Ararat', and 12% for 'Pink Shine' when treated with cooling at night in warm season than the untreated control. In addition, when treated with cooling at night in warm season, the fresh weight of all three cultivars increased by 20-30% statistically significantly than conventionally cultivated control. It is expected that cooling at night in warm season will be helpful to improve the cut flower quality deterioration in summer.

• Science of Emotion and Sensibility
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• v.26 no.2
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• pp.129-140
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• 2023

Following ISO 20471, in this study, first, two sets of safety clothes and safety vests were made by designing and attaching animal and bird patterns preferred by children to retroreflective films and black fabrics on those fluorescent fabrics and retroreflective materials prescribed by international standards. Second, by mounting a smart photonic device on the safety clothing so that the body can be recognized from a distance even without an ambient light source at night, children can emit three types of light depending on the situation with just one-touch of the button. From a result of comparison with visibility a day and night by dressing a mannequin in the made smart safety clothing, the difference in visibility was evident at night, it was confirmed that we can see the figure of a person even at a distance of approximately 70 m. Therefore, it is expected to contribute to the prevention of traffic and other accidents on the road, as the drivers driving at night or in bad weather can recognize a person from a distance. Third, in case of the energy is exhausted and cannot maintain the stability of the light-emitting function of the optical faber, we can use energy harvesting device, and the light-emitting time will be extended. As a result it comes up to emit light stably for a long time. And this prove that smart photonic safety clothing can also be used for night workers. Therefore, optical fiber safety clothing is expected to be highly wearable not only in real life but also in dark industrial sites due to stable charging by applying the energy harvesting provided by solar cells.