• Journal of Biosystems Engineering
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• v.43 no.4
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• pp.342-351
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• 2018

Purpose: Recently, an increasing number of farms have been cultivating shiitake mushrooms using a sawdust substrate and a cooler/heater. In this study, an attempt was made to develop an environmental control system using a heat pump for cultivating high-quality shiitake mushrooms. Methods: An environmental control system, consisting of an air-to-water type heat pump, a thermal storage tank, and a radiator in a variable opening chamber, was designed and fabricated. The system was also installed in the cultivation facility of a farm cultivating shiitake mushrooms so as to compare the proposed control system with a conventional environmental control system using a cooler-condensing unit and an electric hot water boiler. Results: The uniformity of the environment was analyzed through environment measurements taken at several positions inside the cultivation facility. It was determined that the developed environmental control system is able to control the variations in temperature and relative humidity to within 1% and 3%, respectively. In addition, a maximum temperature difference of $30^{\circ}C$ (maximum of $35^{\circ}C$, minimum of $5^{\circ}C$) and a maximum relative humidity difference of 30% (maximum of 90%, minimum of 60%) can be attained within 30 min inside the cultivation facility through the cooling of the heat pump and heating of the radiator in a variable opening chamber. Thus, the developed control system can be used to cultivate high-quality shiitake mushrooms more effectively than a conventional cooler and heater. Conclusions: In comparison with a conventional environmental control system, the developed system decreased the yield of ordinary mushrooms by 65%, and increased that of high-quality mushrooms by 217%. This corresponds to a 16% increase in gross farm income. Consequently, the developed system is expected to improve the income of shiitake mushroom cultivating farms.

• Journal of the Korean Society of Earth Science Education
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• v.10 no.2
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• pp.214-225
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• 2017

The first accurate estimate of the Earth's circumference was made by the Hellenism scientist Eratosthenes (276-195 B.C.) in about 240 B.C. The simplicity and elegance of Eratosthenes' measurement of the circumference of the Earth by mathematics abstraction strategies were an excellent example of ancient Greek ingenuity. Eratosthenes's success was a triumph of logic and the scientific method, the method required that he assume that Sun was so far away that its light reached Earth along parallel lines. That assumption, however, should be supported by another set of measurements made by the ancient Hellenism, Aristarchus, namely, a rough measurement of the relative diameters and distances of the Sun and Moon. Eratosthenes formulated the simple proportional formula, by mathematic abstraction strategies based on perfect sphere and a simple mathematical rule as well as in the geometry in this world. The Earth must be a sphere by a logical and empirical argument of Aristotle, based on the Greek word symmetry including harmony and beauty of form. We discuss the justification of these three bold assumptions for mathematical abstraction of Eratosthenes's experiment for calculating the circumference of the Earth, and justifying all three assumptions from historical perspective for mathematics and science education. Also it is important that the simplicity about the measurement of the earth's circumstance at the history of science.

• Journal of the Ergonomics Society of Korea
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• v.35 no.6
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• pp.581-594
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• 2016

Objective: The purpose of this study is to develop an all- in-one collar shirt with excellent appearance which is well suited to the body shape of the male adults. Background: As men's casual wear has recently become more casual and the number of cool biz wearing in the summer has increased, a variety of shirt colors have been preferred in addition to shirt collar. However, studies on the design and pattern development of men's casual shirt collars are very rare. So we have identified the necessity of various development and research of men's shirts. Method: We collected 8 all-in-one collar patterns for shirts from professional pattern books and men's shirt brands. Also, based on anthropometric data from the 6th Size Korea, we selected 5 subjects with measurements similar to the average adult men, manufactured shirts based on them and conducted a wearing test by 5 experts. Results: After selecting shirts with good fit and appearance, we developed a prototype of all-in-one collar. As for front appearance evaluation, E1 pattern had the most outstanding shape and size, and C1 pattern had the most natural creases and front adjustment curves. As for side appearance evaluation, C1 had the highest overall scores, and E1 pattern on outer line. As for back appearance evaluation, C1 pattern had the highest score. Conclusion: We suggested new all-in-one collar and shirt patterns. In addition, the prototype of the all-in-one collar shirt design was presented by reflecting results of the wearing test and preference survey. Application: The shirt's design and patterns could be manufactured using the developed patterns. It will fit well with the body shape of adult males and will be highly satisfied by them.

• Korean Journal of Food Science and Technology
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• v.4 no.1
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• pp.1-5
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• 1972

This investigation was primarily carried out to establish the optimum conditions for the separation of sorbic acid, as an enzyme inhibitor, from dry mountain ash berries. The berries were crushed to $35{\sim}40\;mesh$, and leached with water to produce a reddish juice, which was concentrated to syrup after evaporation. Parasorbic acid was separated from the syrup by steam distillation in the presence of acid. In this study, the optimum experimental results for separation of parasorbic acid were obtained as follows : (1) the most applicable leaching time of the dry ash berries was about 6 hours at room temperature and less than 4 hours at $40^{\circ}C$ and (2) in steam distillation, after removal of malic acid, addition of 30 ml of sulfuric acid per 50 ml of syrup extracted from 100 g of the ash berries was very adequate. The purity of sorbic acid obtained experimentally through the isomerization technique was qualitatively examined by spectrophotometeric, paper chromatographic, and melting point measurements.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.33 no.1 s.60
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• pp.7-10
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• 2007

The interaction between polymers and surfactants was investigated by means of rheological and surface tension measurements. The polymers used in this study were acrylates/$C_{10-30}$ alkyl acrylate crosspolymer (AC) and ammonium acryloyldimethyltaurate/VP copolymer (AV). And the surfactants were PEG-40 hydrogenated castor oil (HC) and polysorbate 60 (P60). HC and P60 made the micelles intervening between AC polymers, resulting in the increase of viscosity. However, HC showed a similar behavior over the wider range of surfactant concentration than P60. Regarding of surface tensions in the same range of surfactant concentration, AC/HC solution showed the area of increasing surface tension with surfactant concentration in contrast to the AC/P60 solution showing no increasing area. It is assumed that the micelles between AC/HC were formed so cooperatively and strongly that the surfactants located at the surface originally moved to the micelles.

• Journal of the Korean Society of Costume
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• v.63 no.4
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• pp.132-142
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• 2013

This study has evaluated the physiological reaction to wearing brassiere as well as the sensations that the wearer feels in order to understand the effect of brassiere use on the human body. Six healthy women in their twenties were used as subjects and the experiment measured the difference in their S.C.L, Skin Temperature, B.V.P and Pulse. The measurements were made in the following conditions: Women not wearing any brassiere, women wearing sports brassiere, and the women wearing wire brassiere. The results showed significant differences in the following areas. 1. S.C.L was found to be the highest when they didn't wear any brassiere, followed by when they wore wire-brassiere and then sports brassiere. 2. The Skin Temperature was found to be the highest when they wore wire-brassiere, followed by when they wore sports brassiere and when they didn't wear any of them. In particular, when they wore sports brassiere, the B.V.P was found to be the highest when they wore none of them, fir skin temperature dropped as time passed. 3.ollowed by when they wore sports brassiere and then wire brassiere. When they wore sports brassiere, they had irregular blood-flow. 4. Pulse was found to be the highest when they didn't wear any of them, followed by when they wore sports brassiere and then wire brassiere. 5. Those who didn't wear any brassiere felt the most chill, followed by those wearing wire brassiere and then sports brassiere. The moisture level was found to be the highest when they wore sports brassiere, followed by when they wore wire brassiere and then when they wore none of them. Comfort level was found to be the best with no brassiere, followed by wire brassiere and then sports brassiere.

• Advances in nano research
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• v.5 no.3
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• pp.215-230
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• 2017

The development of hybrid systems comprising nanoparticles and polymers is an opening pathway for engineering nanocomposites exhibiting outstanding mechanical, optical, electrical, and magnetic properties. Among inorganic counterpart, iron oxide nanoparticles (IONP) exhibit high magnetization, controllable surface chemistry, spintronic properties, and biological compatibility. These characteristics enable them as a platform for biomedical applications and building blocks for bottom-up approaches, such as the layer-by-layer (LbL). In this regard, the present study is addressed to investigate IONP synthesised through co-precipitation route (average diameter around 7 nm), with either positive or negative surface charges, LbL assembled with sodium sulfonated polystyrene (PSS) or polyaniline (PANI). The surface and internal morphologies, and electrochemical properties of these nanocomposites were probed with atomic force microscopy, UV-vis and Raman spectroscopy, scanning electron microscopy, cross-sectional transmission electron microscopy, and electrochemical measurements. The nanocomposites display a globular morphology with IONP densely packed while surface dressed by polyelectrolytes. The investigation of the effect of thermal annealing (300 up to $600^{\circ}C$) on the oxidation process of IONP assembled with PSS was performed using Raman spectroscopy. Our findings showed that PSS protects IONP from oxidation/phase transformation to hematite up to $400^{\circ}C$. The electrochemical performance of nanocomposite comprising IONP and PANI were investigated in $0.5mol{\times}L^{-1}$ $Na_2SO_4$ electrolyte solution by cyclic voltammetry and chronopotentiometry. Our findings indicate this structure as promising candidate for potential application as electrodes for supercapacitors.

• Environmental Analysis Health and Toxicology
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• v.27
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• pp.13.1-13.10
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• 2012

Objectives: We aimed to investigate the acute effects of heat stress on body temperature and blood pressure of elderly individuals living in poor housing conditions. Methods: Repeated measurements of the indoor temperature, relative humidity, body temperature, and blood pressure were conducted for 20 elderly individuals living in low-cost dosshouses in Seoul during hot summer days in 2010. Changes in the body temperature, systolic blood pressure (SBP) and diastolic blood pressure (DBP) according to variations in the indoor and outdoor temperature and humidity were analyzed using a repeated-measures ANOVA controlling for age, sex, alcohol, and smoking. Results: Average indoor and outdoor temperatures were $31.47^{\circ}C$ (standard deviation [SD], $0.97^{\circ}C$) and $28.15^{\circ}C$ (SD, $2.03^{\circ}C$), respectively. Body temperature increased by $0.21^{\circ}C$ (95% confidence interval [CI], 0.16 to $0.26^{\circ}C$) and $0.07^{\circ}C$ (95% CI, 0.04 to $0.10^{\circ}C$) with an increase in the indoor and outdoor temperature of $1^{\circ}C$. DBP decreased by 2.05 mmHg (95% CI, 0.05 to 4.05 mmHg), showing a statistical significance, as the indoor temperature increased by $1^{\circ}C$, while it increased by 0.20 mmHg (95% CI, -0.83 to 1.22 mmHg) as outdoor temperature increased by $1^{\circ}C$. SBP decreased by 1.75 mmHg (95% CI, -1.11 to 4.61 mmHg) and 0.35 mmHg (95% CI, -1.04 to 1.73 mmHg), as the indoor and outdoor temperature increased by $1^{\circ}C$, respectively. The effects of relative humidity on SBP and DBP were not statistically significant for both indoor and outdoor. Conclusions: The poor and elderly are directly exposed to heat waves, while their vital signs respond sensitively to increase in temperature. Careful adaptation strategies to climate change considering socioeconomic status are therefore necessary.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.37 no.4
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• pp.406-412
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• 2009

Flight simulation model for helicopter simulator is one of the most important models which affect flight performance and handling quality. It is typical to develop the model based on the raw data and models from the helicopter designers/manufacturers. The approaches in this study were to develop the basic model based on the available resources regarding helicopter operation/maintenance and to tune and validate it based on the flight test results. The basic model was developed with maintenance manuals, flight manuals, analyses, measurements, papers and so on considering that KA-32T data could not be obtained from the manufacturer. The flight test for KA-32T was performed and the reference data for the simulation validation tests were acquired. The flight simulation model was validated to have the fidelity compatible with level C of FAA AC120-63 after comparison and tuning with flight test results.

• Journal of the Korean Society of Physical Medicine
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• v.9 no.3
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• pp.271-278
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• 2014

PURPOSE: This study researched the effects of different types of high heels on the muscles surrounding the cervical spine, the thoracic spine, and the lumbar spine by analyzing muscle activation of the paraspinal muscles during walking while wearing high heels. The high heels were all of the same height: 8cm. METHODS: The 28 subjects in this experiment were females in their 20s with a foot size of 225-230mm. To measure the muscle activation of the paraspinal muscles, EMG electrodes were attached on the paraspinal muscles around C6, T7, and L5. The muscle activation during walking while wearing 8cm high wedge heels, setback heels, and french heels was measured. The measurements were performed 3 times each and the mean value of the result was used for analysis. Two kinds of velocity were used in this study. One of the velocity was 2.5 m/s. The other was 3.5 m/s. RESULTS: The muscle activation of paraspinal muscles increased significantly according to increase of walking velocity. But there was no significant difference according to the heel types. CONCLUSION: In view of the results, the height of heels and the velocity of walking are more convincing variables than the width of the heels on the muscle activation of paraspinal muscles. So wearing high heels is not recommended for those who have pain or functional problem of cervical and lumbar vertebrae.