• Journal of the Korean Society of Safety
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• v.33 no.2
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• pp.39-44
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• 2018

Dust explosions are occurring in a variety of industries. A dust explosion caused by a specific energy generates huge amount of energy in the ignition and releases decomposition gas. Damages can be increased since this released decomposition gas can cause second and subsequent explosions. In this study, the goal was to obtain practical information on what could affect the explosion by comparing the characteristics of two kinds of dusts with completely different chemical properties. Three kinds of dusts were measured and evaluated for explosion pressure, dust explosion index, explosion limit and minimum ignition energy. It is possible to grasp the characteristics of each dust and use it as useful accident prevention data in the production of raw material powder.

• Journal of the Korean Society of Clothing and Textiles
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• v.29 no.11
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• pp.1399-1409
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• 2005

The purpose of this study was to analyze the shape of gathered skirts using a three-dimensional measurement system. And in this experiment, I try to accumulate three-dimensional data of wearing model and to figure out analyzing method made by shape of clothes. The experimental design consists of two factorial designs. I set up three different kinds of fabrics, ratio of gathers. Therefore nine samples were made. The instrument and tools for three-dimensional measurement was whole body 3D scanner. Analysis program used in experiment is RapidForm 2004 PP1 and Pattern Design 2000. Data analysis utilizes SPSS WIN 10.0 Package. T-test to effect an inspection of evidence, there was difference about measurement times. One-way ANOVA to analysis effect of gather made by gathering conditions. The following results were obtained; 1. As a result of inspecting an error several times using a three-dimension measurement system, convinced data was obtained. 2. At front, distribution of gap amount was larger than back. And as ratio of gathers increased, distribution of gap amount showed regularly. 3. After analyzing horizontal sectional figure of skirts, as a height of skirt changed from waist to the bottom of skirts, the results showed as follows. While section width, section thickness, node width, node depth increased, node count decreased. 4. With the horizontal section levels of gather skirt, the silhouette on middle hip section was similar with the silhouette of body line. And as ratio of gathers around hip section increased, nodes showed regularly. At the bottom of skirts showed different nodes by different gathering condition.

• Journal of electromagnetic engineering and science
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• v.12 no.1
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• pp.122-127
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• 2012

Post-wall waveguide structures have attracted a great deal of attention for micro- and millimeter-wave applications. One of the waveguide’s applications is a slotted waveguide array. In order to design the slotted array, the characteristics of a slot unit alone on the post-wall waveguide should be investigated. In this paper, a method for extracting the S-parameters of a unit slot is proposed. This simple method requires only two kinds of waveguides: waveguides without a slot unit and waveguides with a slot unit. Three kinds of slot units are fabricated, and the extracted results show a high level of agreement with predicted (simulated) results. With this method, the equivalent slot length can also be found.

• Korean Journal of Rural Living Science
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• v.6 no.1
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• pp.25-30
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• 1995

This study was designed to obtain the basic data developing the UV ray protective garments for the plastichouse workers. Two subjects were volunteered for 1hr. wear test in plastic house, and the ensembles was composed of one of three kinds blouse (UV blocking blouse, polyester/cotton 47/53 blouse, and polyester blouse), shorts, sleeveless undershirts, pants and socks. The measurements were rectal temperature, skin temperature, microclimate inside clothing, subjective sensation, and the colour difference of UV sensor. The results were as follows: 1. Microclimate especially, temperature inside clothing of polyester blouse was the highest among the garments. And UV-proof polyester blouse showed the lower mean skin temperature and microclimate than others. Showing the highest sweat volume. 2. No significant difference on UV ray blocking function among 3 kinds of garment was shown. 3. We could conform that in spring for the plastic house wぉw s garment low thermal insulating value and wide covering area were more important factors than UV blocking function of fabric.

• Journal of the Korean Home Economics Association
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• v.25 no.3
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• pp.95-106
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• 1987

The purpose of this study is to investigate educational and occupational value orientations and transmissions between parents and college-aged children. The specific objectives are as follows; 1. To investigate parents and children's value orientations. 2. To estimate value congruence and transmissions between parents and children. 3. To find out the effects of three kinds of variables (demographic, family life, and expectation) on children's value orientations. To study the generational congruences and transmissions, four kinds of questionnarie and matched samples of mother-daughter and father-son were used. The data were obtained through 110 pairs and analyzed by t-test, Pearson's correlation, and multiple regression. The resluts are summerized as follows; 1. Significant value differences are found between parents group and children group. 2. Mother-daughter congruences are more than father-son congruences, but the correlation coefficients are low. 3. The variables selectively influence on children's value orientations.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.35 no.1
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• pp.19-26
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• 2003

In recent years, numerous studies have been carried out to find out the possible substitution of PE-coated paperboards used in packaging of watery or oily foods. Accordingly, this study was carried out to obtain the basic data for producing higher functional coating agents for pulp mold by evaluating various kinds of mixed coating agents. At that time, two kinds of synthetic coating agents(AKD, PYA) and three kinds of natural coating agent(CMC, corn starch, oxidized starch) were used for making the mixed coating agents respectively. Physical properties of coated paperboards were tested. Conclusions obtained from this study were as follows. Based on concentrations, the proper mixture ratios were 10:90(AKD:CMC), 10:90(AKD:corn starch), 10:90(AKD:oxidized starch), 40:60(PVA:CMC), 20:80(PVA:corn starch) and 20:80(PYA:oxidized starch). The mixed coating agent of PYA:corn starch(20:80) was the most efficient coating agent. Consequently, water and oil resistance were improved even with much addition of natural coating agents. We consider that they can be suitable for the packaging used in the storage of higher moisture vegetables and other food, and also can be suitable for oily fried food.

• The Korean Journal of Applied Statistics
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• v.35 no.3
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• pp.421-434
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• 2022

Chatterjee (2021) proposed a new correlation coefficient ξ. Focusing on two questions (1. Is ξ coefficient distinguishable for Anscombe's quartet data set?, 2. How does the ξ coefficient value change according to the number of data for various kinds of scatterplots?), an exploratory data analysis is attempted for ξ coefficient. We can compare three measures (ξ coefficient, Pearson's correlation coefficient and mutual information).

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2003.09a
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• pp.1-6
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• 2003

Associations, as specific forms of knowledge, reflect relationships among items in databases, and have been widely studied in the fields of knowledge discovery and data mining. Recent years have witnessed many efforts on discovering fuzzy associations, aimed at coping with fuzziness in knowledge representation and decision support processes. This paper focuses on associations of three kinds, namely, association rules, functional dependencies and pattern associations, and overviews major fuzzy logic extensions accordingly.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.10a
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• pp.751-754
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• 1999

Corrosion inhibitors are widely used to protect chloride-induced corrosion of reinforcement in concrete. However, the number of researches on the corrosion of reinforcement, when corrosion inhibitor is used, is not enough for actual application in the field. In addition, on corrosion of reinforcement a quantitative standard about corrosion inhibitor does not exist and the data about its influencing concrete are relatively rare. In this study, the effectiveness of rebar corrosion protection, setting time, compressive strength, chloride ion's penetration, and diffusion test were performed using with three different kinds of corrosion inhibitors.

• Physical Therapy Korea
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• v.9 no.3
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• pp.93-99
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• 2002

Traditionally, ultraviolet (UV) has been used for treating the pressure sore and skin wound. The effects of UVA and UVB radiation on disinfection have been reported. The purpose of this study was to examine the effectiveness of UVC radiation on disinfection of Escherichia coli, Staphylococcus aureus, Salmonella typhimurium in vitro. Three bacterium were radiated by UVC (250 nm, 20 seconds) and incubated at $37^{\circ}C$ for 24 hours at the agar culture medium. Kill rates of all three bacterium were 99.9%. UVC radiated on three kinds of bacterium for 30 or 60 seconds. Kill rates were 99.9% both 30 and 60 seconds. This data suggests that UV light at 250 nm could be a useful method to minimize infection and shorten healing time in pressure sore and skin wound condition.