• Transactions of the Korean Society of Mechanical Engineers B
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• v.25 no.9
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• pp.1157-1164
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• 2001

Centrifugal fans are widely used and the noise generated by these machines causes one of the most serious problems. In general, the centrifugal fan noise is often dominated by tones at BPF(blade passage frequency) and its higher harmonics. This is a consequence of the strong interaction between the flow discharged from the impeller and the cutoff in the casing. However, only a few research have been carried out on predicting the noise because of the difficulty in obtaining detailed information about the flow field and casing effects on noise radiation. The objective of this study is to understand the generation mechanism of sound and to develop a prediction method for the unsteady flow field and the acoustic pressure field of a centrifugal fan. We assume that the impeller rotates with a constant angular velocity and the flow field of the impeller is incompressible and inviscid. So, a discrete vortex method(DVM) is used to model the centrifugal fan and to calculate the flow field. The force of each element on the blade is calculated by the unsteady Bernoulli equation. Lowsons method is used to predict the acoustic source. In order to compare the experimental data, a centrifugal impeller and wedge introduced by Weidemann are used in the numerical calculation and the results are compared with the experimental data. Reasonable results are obtained not only for the peak frequencies but also for the amplitudes of the tonal.

• Ocean and Polar Research
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• v.28 no.3
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• pp.225-236
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• 2006

Seagrass meadows are considered as critical habitats for a wide variety of marine organisms in coastal and estuarine ecosystems. In many cases, studies on the spatial/temporal distribution of seagrass have depended on direct observations using SCUBA diving. As an alternative method fur studying seagrass distribution, an application of hydroacoustic technique has been assessed for mapping seagrass distribution in Dongdae Bay, on the south coast of Korea, in September 2005. Data were collected using high frequency transducer (420 kHz split-beam), which was installed with towed body system. The system was linked to DGPS to make goo-referenced data. Additionally, in situ seagrass distribution has been observed using underwater cameras and SCUBA diving at four stations in order to compare with acoustic data. Acoustic survey was conducted along 23 transects with 3-4 blot ship speed. Seagrass beds were vertically limited to depths less than 3.5m and seagrass height ranged between 55 and 90cm at the study sites. Dense seagmss beds were mainly found at the entrance of the bay and at a flat area around the center of the bay. Although the study area was a relatively small, the vertical and spatial distributions of the seagrass were highly variable with bathymetry and region. Considering dominant species, Zostera marina L., preliminary estimation of seagrass biomass with acoustic and direct sampling data was approximately $56.55g/m^2$, and total biomass of 104 tones (coefficient variation: 25.77%) was estimated at the study area. Hydroacoustic method provided valuable information to understand distribution pattern and to estimate seagrass biomass.

• Textile Coloration and Finishing
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• v.22 no.3
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• pp.194-206
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• 2010

This study was carried out to identify the optimum dyeing conditions for maximum dye uptake of Prunus yedoensis Matsumura flower extract on silk fabric and to investigate hue/tone characteristics and fastness properties of the dyed fabrics. As results, the flower extract was found to contain flavonoids by FT-IR and to show yellowish shade by UV-vis spectrum. Silk fabric was optimized for maximum dye uptake to five repetitions of dyeing at $80^{\circ}C$ for 60 min with an extract concentration of 600% owf in terms of both K/S and color differences. Pre-mordanting was more effective to dye uptake than post-mordanting for all of the mordants used. Un-mordanted and pre-mordanted fabric showed YR(Yellow Red) while most of post-mordanted ones did Y(Yellow). Main tones of dyed fabrics were sf(soft) and lt(light) in the case of unmordanting or Al-mordanting whereas they were d(dull) and g(grayish) by post-mordanting with Cu, Cr, and Fe, respectively. The fastness grades to rub and dry cleaning were reasonably good for most dyeing conditions while those to light were poor. Finally dyeing condition for each hue/tone of the dyed silk with the flower extract was optimized considering fastness properties.

• Journal of the Korea Fashion and Costume Design Association
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• v.7 no.3
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• pp.17-26
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• 2005

In this research, in order to find out the effect of the area ratio in the harmonic sense assessment of the coloration of Korean clothes, the coloration of a Korean jacket and a skirt was compounded with a similar coloration and a contrast coloration. The respondents were asked to evaluate 16 stimuli of the traditional Korean skirt and jacket with the coloration of the Korean jacket/ skirt, the skirt/ Korean jacket was separately compounded to be 4 tones such as vivid, light, dull, dark. The subjects were 44 female undergraduate students. The results of each can be summerized as follows. As to similar coloration, the korean yellow jacket and red skirt, Korean students feel vivid and dull tone was harmonious, and American students feel vivid, light, and dark tone were harmonious coloration. In inversed case, red korean jacket and yellow skirt, both countries' students recognized that the vivid tone was harmonious. Korean students gave higher points to korean traditional dress in similar coloration such as yellow korean jacket which was small area and red skirt which was large area coloration than inversed color area ratio which red korean jacket and yellow skirt. As to contrast coloration, the korean green jacket and red skirt, Korean students feel vivid tone was harmonious, and American students feel vivid, dark tone were harmonious coloration. In inversed case, red korean jacket and green skirt were recognized that any tone was not harmonious for both countries' students. Both countries of student showed the culture gap. Compared with American students, Korean students were familiar with korean dress's traditional coloration, as a result familiar coloration was recognized harmonious coloration.

• Journal of the Korea Fashion and Costume Design Association
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• v.11 no.1
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• pp.77-85
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• 2009

In modem society, fashion is used as a means to express oneself. Colors in fashion are regarded as one of the important design elements and play a significant role. Today men's fashion trend represents to adopt diverse silhouettes, colors and various materials. They can choose diverse color for men's fashion. Brown has been popular colors for both man and woman. It usually represents the image of warm, comfort and classic. This research analyzed Brown whose diverse uses had been observed in fashion and the characteristics of Brown the color combinations in men's fashion through men's fashion collection from 2000 to 2008. The characteristics of color combinations with Brown analyzed two color combinations for the top and bottom as follows: First, the hue characteristics of Brown two color combinations were analyzed in men's fashion. Second, the tone characteristics of Brown two color combinations were analyzed in men's fashion. Third, the characteristics of color combinations were analyzed in the Brown top and bottom according to the hues in men's fashion. The Brown color combinations were analyzed according to the 10 hues and achromatic colors. As a result, 10YR was most used in both the top and bottom in F/W and S/S. As for the Brown color combinations of the 12 tones and achromatic colors in the top and bottom, dark grayish was the most used in S/S and F/W regardless of the seasons. The Brown color combinations in men's fashion were analyzed in terms of characteristics. As a result, 10YR and 2.5Y were most used. They were also of the highest frequency in the color combinations of Brown tops and bottoms.

• Biomolecules & Therapeutics
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• v.14 no.2
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• pp.67-74
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• 2006

EoL-1 cells differentiate into eosinophils in the presence of n-butyrate, but the mechanism has remained to be elucidated. Because n-butyrate can inhibit histone deacetylases, we hypothesized that the inhibition of histone deacetylases induces the differentiation of EoL-1 cells into eosinophils. In this study, using n-butyrate and two other histone deacetylase inhibitors, apicidin and trichostatin A, we have analyzed the relationship between the inhibition of histone deacetylases and the differentiation into eosinophils in EoL-1 cells. It was demonstrated that apicidin and n-butyrate induced a continuous acetylation of histones H4 and H3, inhibited the proliferation of EoL-1 cells, and induced the expression of markers for mature eosinophils such as integrin ${\beta}7$, CCR1, and CCR3 on EoL-1 cells, while trichostatin A evoked a transient acetylation of his tones and induced no differentiation into eosinophils. These findings suggest that the continuous inhibition of histone deacetylases in EoL-1 cells induces the differentiation into mature eosinophils.

• Journal of Fashion Business
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• v.17 no.6
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• pp.98-110
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• 2013

This research is to study the functional color arrangement of work clothes based on the color chroma value arrangement, which could affect the safety of workers at the site of the mechanical industry. For the study, 5PB hue, indicating a high satisfaction level with proper colors at the site of the mechanical industry, were selected from previous research for 6 types of CAD simulation on a 2-color chroma value arrangement. To analyze the color data of each color arrangement after applying the color chroma value arrangement as well as to figure out the level of recognition on the color arrangement, an analytical result, which was based on the NCS color system, was evaluated. Furthermore, the survey study on items regarding the safety of the relevant work site for the simulated result was executed. As a result of the evaluation, the color arrangements which include high color chroma value indicated a high satisfactory level in all items under the visibility criteria for the safety of workers, propriety as a color arrangement of work clothes, and safety from the perspective of work site management. In particular, the color arrangement mixture between high color chroma obtained the highest satisfactory evaluation, indicating that the color arrangement of high color chroma is essential in the color arrangement of work clothes for the establishment of safety by adjusting the color chroma value. Yet, in order to figure out the independent function of the color chroma value, other factors are restricted in this study. Thus, it is not proper to apply the result of this study only at the actual work site. Therefore, a follow-up research centered on the tones of all three types is proposed, from which we can expect, a suggestion of the applicable color guideline for the industrial site.

• Korean journal of food and cookery science
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• v.26 no.2
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• pp.111-120
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• 2010

The aim of this research was to develop a practical use of the citron (Citrus junos Sieb.) leaf, which is a by-product of the citron cultivation, by introducing it into the Jeolpyun, one of the most popular rice cakes in Korea. To achieve the goals of this research, the citron leaf Jeolpyun (CLJ) was first precipitated. The sensory properties and physical examination of products containing 0 (control), 1.0, 1.5, 2.0, and 2.5% of the dried citron leaf powders were then assessed by employing sensory evaluations and instrumental measurements for texture and color. A total of one-hundred and fifty women panelists in age categories of 20s, 30s, 40s, and over 50 were randomly selected from residents in the Seoul area. In general, the highest sensory evaluation scores were obtained for CJLs containing 2% of the citron leaf powders by all panel groups although there was some variation. As levels of the citron leaf powder in the CLJ increased, the texture parameters such as hardness, cohesiveness, and gumminess of the CLJ as measured by the Texture Analyzer significantly increased while adhesiveness decreased and springiness remained constant. Accordingly, the optimal amount of citron leaf powder was determined to be 2% or less for CLJ in order to maintain the original texture of the Jeolpyun. As the levels of the citron leaf powder increased in the CLJ, the Hunter colorimetric L-and a-value significantly decreased while the b-value significantly increased. In other words, the CLJs became darker, as well as deeper in green and yellow tones as the levels of the citron leaf powder increased. The above results indicate that the citron leaf could be successfully used for preparation of Jeolpyun at a concentration around 2%(w/w) based on the consumer preference test and instrument analysis of the products. This research is expected to contribute to the industrial use of citron leaf powder in Jeolpyun and other food products.

• Economic and Environmental Geology
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• v.32 no.1
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• pp.73-82
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• 1999

The objectives of this study are to investigate soil contamination in the vicinity of abandoned Au-Ag mine and to apply a remediation technique of liming to tailings. In the study area of the Imcheon Au-Ag mine, soils were sampled in and around the mine the analyzed by Atomic Absorption Spectrometry extracted by both 0.1N HCl and aqua regia. Elevated levels of Cd, Cu, Pb and Zn concentrations extracted by 0.1N HCl were found in soils taken from tailings site. These high contents directly influenced metal concentrations in soils taken in the vicinity of the site. This is mainly due to clastic movement by wind and effluent of mine waste water. In addition, relatively enriched concentrations of the metals were found in soils extrated by aqua regia due to strong decomposition of the samples compared with 0.1N HCl extration. According to the statistical approach, metal concentrations in soils by 0.1N HCl had a positive correlation with those by aqua regia extraction. Mine waste waters and stream waters were also sampled around the mine in spring and summer and analyzed by AAS for Cd, Cu, Pb and Zn, and by Ion Chromatography for anions. Like soils developed over tailings, significant levels of metals and sulphates were found in the mine waste waters ranging of 0.2~0.3, 0.5~2.0, 0.2~2.8, 30~50 and 1,240~4,700 mg/l of Cd, Cu, Pb, Zn and $SO_4^{2-}$, respectively. These elevated levels influenced in the stream waters in the vicinity of the tailings site. In seasonal variation of metal and anion contents, relatively high levels were found in waters sampled on summer due to leaching the metals and anions from tailings by rain. This study also examined the possibility of lime treatment for remediation of acid mine tailings and assumed to be 46 tones of pulverized lime for neutralization of the tailings.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.48 no.4
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• pp.479-486
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• 2012

In order to obtain the fundamental data about the behavior of conger by underwater audible sound, this experiment was carried out to investigate the hearing ability of Conger eel Conger myriaster which was in the coast of Jeju Island by heartbeat conditioning method using pure tones coupled with a delayed electric shock. The audible range of conger eel extended from 50Hz to 300Hz with a peak sensitivity at 80Hz including less sensitivity over 200Hz. The mean auditory thresholds of conger eel at the frequencies of 50Hz, 80Hz, 100Hz, 200Hz and 300Hz were 105dB, 92dB, 96dB, 128dB and 140dB, respectively. The positive response of conger eel was not evident after the sound projection of over 200Hz. At the results, the sensitive frequency range of conger eel is narrow in spite of swim bladder. Auditory masking was determined for Conger eel by using masking stimuli with the spectrum level range of about 60~70dB (0dB re $1{\mu}Pa/\sqrt{Hz}$). According to white noise level, the auditory thresholds increased as compared with thresholds in a quiet background noise including critical ratio at 68dB of white noise from minimum 26dB to maximum 30dB at test frequencies of 80Hz and 100Hz. The noise spectrum level at the start of masking was distributed at the range of about 68dB within 80~100Hz.