• Proceedings of the Korea Concrete Institute Conference
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• 2000.04a
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• pp.223-228
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• 2000

Although construction company try to get good quality control it's enough to study about developing objective evaluation method and checking quality method. It is important to meaning concrete quality at placing point, immediate quality checking method is limited. The purpose of this study is to develop new method to know early 28-day concrete for getting faithful quality control. The results of this study are as follows :1) With sealed molds, reduced moisture volatilization to more than 50% and enlarged 20% accelerated compressive strength than before one. 2) Accelerated compressive strength of concrete specimen shows higher strength when it was in the air for long time 3)Interrelation with 7-day and 28-day strength were 0.781,0.90, It is higher than before one

• Korean Journal of Food Science and Technology
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• v.22 no.3
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• pp.229-233
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• 1990

The thermal analysis method has been proposed for the evaluation of the relative qualities of different ginger oleoresin samples and discussed to demonstrate its simple applicability. TGA measurement to compare characteristics of ginger oleoresins give more sensitive indication on the thermal decomposition than that of DSC. The results show that the quality of oleoresin obtained from sliced sun dried ginger is better than that from hot air dried whole ginger.

• KIEAE Journal
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• v.9 no.6
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• pp.19-26
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• 2009

In modern architecture, the air-tight construction aimed at saving the energy rather causes ventilation problems and the artificial materials for cost reduction worsen the residential quality. To deal with such negative effect, the study on evaluating the health performance becomes increasingly critical. Among the various factors such as design quality, selected material, construction method and mechanical system that shall be subject to evaluation to identify the health performance of the building, the study was aimed at investigating the legal standards associated with healthy building in various countries. Such evaluation items will provide inputs for an attempt to build legal criteria for a building health performance rating system in Korea.

• Journal of Korean Society for Atmospheric Environment
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• v.18 no.5
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• pp.355-362
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• 2002

There has been relatively a few studies that focused on evaluation of uncertainty for standard methods by which criteria pollutants are analyzed in ambient air. Especially, uncertainty evaluation has not been made yet for sampling and analysis of airborne NO$_2$. Ambient NO$_2$ has been thought to be a major criteria pollutant worldwide because of the potential of ozone formation as well as of its own toxicity. In this study, we tried to assess uncertainties associated with the every step of sampling and of analytical procedure of Griess-Saltzman method. Quality assurance (QA) and quality control (QC) were also emphasized with the uncertainty characterization. The use of Griess-Saltzman method for ambient NO$_2$ analysis showed very uniform daily concentration distribution with the mean of 10.8 ppb and the standard deviation of 1.08ppb during the sampling period. However, seven daily samples collected at the same sampling time and place exhibited highly different concentration distribution. Therefore, we evaluated uncertainties associated with sampling and analysis through the precise application of ISO Guide. Estimates of expanded uncertainties for a total of 62 samples fell in a relatively broad range of 5.17% to 11.85%. On the other hand. the expanded uncertainties were smaller for the high concentration range of greater than 15ppb.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2008.04a
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• pp.689-692
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• 2008

Noises from ceiling mounted air-conditioning units were recorded in various actual situations such as offices, classrooms and libraries. Eight specimens of air-conditioners from major domestic and foreign manufacturers' were investigated in this study. A head and torso simulator was located 1.5 m beneath the air-conditioner panel for the measurements and sound pressure levels of the recording sounds were varied from 28 to 55 dBA with 3 dB steps for subjective evaluations. A total of 88 stimuli was randomly presented to subjects using a headphone system in semi-anechoic chamber. Two-categorized (noisiness and amenity) nine-point scale was used as evaluation method. The third scale ('point 3') among the nine-point scale was set as the threshold of allowable level of the air-conditioning sounds in consideration of the real situations. The results indicate that the allowable sound pressure level is around 34 dBA for both noisiness and amenity categories.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.3
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• pp.357-362
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• 2011

Air springs are prevalently used as suspension in train. However, air springs are seldom used in automobiles where they improve stability and comfort by enhancing the impact-relief, breaking, and cornering performance. Thus, this study proposed a new method to analyze air springs and obtained some reliable design parameter which can be utilized in vehicle suspension system in contrast to conventional method. Among air spring types of suspension, this study focused on sleeve type of air spring as an analysis model since it has potential for ameliorating the quality of automobiles, specifically in its stability and comfort improvement by decreasing the shock through rubber sleeve. As a methodology, this study used MARC, as a nonlinear finite element analysis program, in order to find out maximum stress and maximum strain depending on reinforcement cord's angle variation in sleeves. The properties were found through uniaxial tension and pure shear test, and they were developed using Ogden Foam which is an input program of MARC. As a result, the internal maximum stresses and deformation according to the changes of cord angle are obtained. Also, the results showed that the Young's modulus becomes smaller, then maximum stresses decrease. It is believed that these studies can be contributed in automobile suspension system.

• Journal of the East Asian Society of Dietary Life
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• v.22 no.1
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• pp.25-32
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• 2012

This study was conducted to evaluate the quality characteristics of Sulgidduk prepared with different amounts of Hasuo (Polygoni Multiflori Radix) powder. Proximate composition analysis showed that the moisture content, pH, acidity, and volume of Sulgidduk decreased with a rise in the level of added hasuo powder. The L-value decreased, while a and b values increased, with increasing amounts of hasuo powder. In mechanical evaluation of physical properties, hardness decreased while springiness, chewiness, cohesiveness, and brittleness increased with increasing hasuo powder content. Scanning election microscopy indicated that the number of air cells decreased as the ratio of hasuo powder increased. Sensory evaluation showed that moistness and springiness decreased significantly when the amounts of hasuo powder increased. The sample containing 30 g hasuo powder scored the highest for sweet taste, savory taste, springiness, chewiness, swallowing, and in overall acceptability scores. Next, the sample containing 60 g hasuo powder scored higher than control. The optimum concentration indicate that addition of 30~60 g hasuo powder to Sulgidduk resulted in highest quality.

• Korean journal of food and cookery science
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• v.22 no.5 s.95
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• pp.591-599
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• 2006

The purpose of this study was to investigate the effect of the addition of various concentrations of sea mustard powder on the quality characteristics of Bacsulgi. The sea mustard powder was added to rice powder at ratios of 3, 5, 7, and 9%(w/w). The moisture contents and salinity of Bacsulgi were increased with the addition of sea mustard powder. The incorporation of sea mustard powder in Bacsulgi lowered the lightness values but increased the blueness and yellowness values. Rheology test showed that hardness was significantly (p<0.05) decreased with increasing sea mustard powder content. The springiness and cohesiveness were decreased, whereas the adhesiveness was increased, with increasing sea mustard powder content. Scanning electron microscopy showed that the size of the air cells increased and the surface of rice powder swelled with increasing sea mustard powder content. The result of sensory evaluation showed that there were significant (p<0.05) differences in the scores of smell and taste sensory characteristics among the samples. The overall eating quality was the highest in the control and decreased with increasing sea mustard powder level. The study results suggested that Bacsulgi prepared with up to 5% addition of sea mustard powder was as acceptable as Bacsulgi prepared without sea mustard powder.

• Journal of Korean Society for Atmospheric Environment
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• v.18 no.6
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• pp.527-538
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• 2002

In this study, the performance of sampling and of analytical methodology was examined against a number of selected volatile organic compounds (VOCs) in the ambient air. The canister-based sampling method for VOCs has been a viable and widely used approach that is based on research and evaluation performed over the past several years. VOCs were determined using canisters by GCMSD analysis. A total of target analyses in this study included approximately 30 VOCs designated in TO-l4A categories including BTEX. The methodology for QC(quality control) was intensively investigated with a wide range of performance criteria such as; (1) cleanliness of canisters, (2) reproducibility of diluter, (3) instrumental detection limits of preconcentrator and GCMSD, and (4) precision and accuracy of GCMSD. For most of the compounds tested, precision was less than $\pm$5%, IDL was 0.2 ppbv, accuracy was $\pm$5%, respectively. This study demonstrated that the combination of canister sampling and GC/MSD analysis could be reliably applied to the measurements of BTEX in ppbv levels that are typically observed in/outdoor air environment.

• Food Science and Preservation
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• v.4 no.2
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• pp.147-153
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• 1997

Oriental melon has been increased in production amount, but its processed food was not made in spite of the fact that shelf-life of the fresh fruit is short. This study was carried out to develop a dried product with no use sulfur treatment. Fresh melons were peeled, cut into 6 pieces, and soaked to the following pretreatments soaking in sugar syrup(SS), sodium chloride(SC), ascorbic acid(AA) and sodium polyphosphate(SP). After preatreatments the melon pieces were dried by hot air drying at 5$0^{\circ}C$ for 9 and 12 hours, and the dried melons were air blown at $25^{\circ}C$ for 1 day. The dried samples were evaluated for moisture content, texture, rotor, and sensory quality. The moisture content of dried melons soaked in SS and SC were lower than those that were soaked in AA and SP after hot air drying. The melons dried for 12 hours were high in hardness, gumminess, chewness and adhesiveness and excellent in sensory evaluation compared to 9 hours. The "L" value of SS was higher and the "a" value was lower in Hunter color. And SS treatment inhibited browning of the dried melon and improved sensory characteristics in color, flavor, texture and taste. Sucrose concentration had no significant effect on color, hardness and sensory score in banal product. The combination of SS with SP represented a highly effective antibrowning treatment for the dried melon and the product was kept in good color for 3 months at room temperature.at room temperature.