• International Journal of Highway Engineering
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• v.9 no.4
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• pp.117-127
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• 2007

The exposed aggregate PCC(EAP) pavements have been successfully used in Europe and Japan as low-noise pavements. Coarse aggregate are exposed on the pavement surface texture of EAP by removing mortar of surface. The pavement surface texture should maintain not only low-noise characteristic but also adequate skid resistance level during the performance period. Skid resistance decreased with wearing and polishing of tire and pavement surface due to the repetition of tire-pavement contact. Since the tires mainly contact the exposed coarse aggregate, the shape and rock type of coarse aggregate significantly influence wearing and polishing of EAP pavements. The test for resistance to abrasion coarse aggregate by use of the Los Angeles machine(KS F 2508) and the method of test for resistance to abrasion coarse aggregate by use of the Accelerated Polishing Machine(ASTM D 3319-90) are generally used to evaluate polishing characteristics of aggregate. In this study, polishing of coarse aggregate of different five rock types were evaluated by KS F 2508(LA abrasion test) and ASTM D 3319-90(PSV method). The results of LA abrasion test and PSV method were contrary to each other. Since LA abrasion test is estimated the quantity of abrasion by the impact of aggregate, it may not be adequate to evaluate the polishing of aggregate by the repetition of tire. In the case of PSV method, the resistance of polishing is estimated the skid resistance variation of polished aggregate after repetition of tire. The PSV method is adequate for the evaluation on polishing of coarse aggregate. From the test results of PSV method, it was founded that rock type, specific gravity, coarse aggregate angularity, flat or elongated particles in coarse aggregate are significant to the resistance characteristic of coarse aggregate.

• Journal of Food Hygiene and Safety
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• v.39 no.2
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• pp.61-71
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• 2024

In this study, we analyzed chlorogenic acid indicator components in preparation for the additional listing of green coffee bean extract in the Health Functional Food Code and optimized caffeine for simultaneous analysis. We extracted chlorogenic acid and caffeine using 30% methanol, phosphoric acid solution, and acetonitrile-containing phosphoric acid and analyzed them at 330 and 280 nm, respectively, using liquid chromatography. Our analysis validation results yielded a correlation coefficient (R²) revealing a significance level of at least 0.999 within the linear quantitative range. The chlorogenic acid and caffeine detection and quantification limits were 0.5 and 0.2 ㎍/mL and 1.4, and 0.4 ㎍/mL, respectively. We confirmed that the precision and accuracy results were suitable using the AOAC validation guidelines. Finally, we developed a simultaneous chlorogenic acid and caffeine analysis approach. In addition, we confirmed that our analysis approach could simultaneously quantify chlorogenic acid and caffeine by examining the applicability of each formulation through prototypes and distribution products. In conclusion, the results of this study demonstrated that the standardized analysis would expectably increase chlorogenic acidcontaining health functional food quality control reliability.

• Journal of Food Hygiene and Safety
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• v.34 no.3
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• pp.242-250
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• 2019

An analytical method was developed for the determination of fenquinotrione, a triketone herbicide, in agricultural products. Fenquinotrione was metabolized to KIH-3653-M-2 in plants. Analyte extraction was conducted using 2% formic acid in acetonitrile and cleaned up using a hydrophillic-lipophillic balance (HLB) cartridge. The limits of detection (LOD) and quantification (LOQ) were 0.004 and 0.01 mg/kg, respectively. Matrix-matched calibration curves were linear over the calibration ranges ($0.001{\sim}0.1{\mu}g/mL$) into a blank extract with $r^2>0.99$. The recovery results for fenquinotrione and KIH-3653-M-2 ranged between 81.1 to 116.2% and 78.0 to 110.0% at different concentration levels (LOQ, $10{\times}LOQ$, $50{\times}LOQ$) with relative standard deviation (RSD) less than 4.6%. All values were corresponded with the criteria ranges requested in both the Codex (CAC/GL 40-1993, 2003) and MFDS guidelines (2016). Therefore, the proposed method can be used as an official analytical method for determination of fenquinotrione in the Republic of Korea.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.28 no.4
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• pp.57-76
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• 2017

The purpose of this study is to investigate the determinants of the quality of Web-based legal information services and their significant influences on the user continuance intentions. Based on the main dimensions of the SERVQUAL, this study conceptualizes five dimensions of reliability, assurance, design, empathy, and responsiveness. It measures the level of expectation and satisfaction on the basis of these five dimensions. Regression analysis was conducted to extract and analyze the determinants of the service quality and the factors affecting continuous intention. The level of legal information service quality is superior in empathy, responsiveness, and design category, but it is relatively insufficient in reliability and assurance category. In the reliability category, the relevance of the search results was an issue. The problems related to the authority and information sources were recognized as important. Reliability implies that there is a relatively close relationship between empathy and responsiveness, and that it is necessary to improve the quality of contents such as empathy and responsiveness in order to increase reliability. In order to increase the ongoing use of legal information services in the future, it is more effective to make sure that assurance is top priority.

• 대한공업교육학회지
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• v.31 no.2
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• pp.128-154
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• 2006

In the knowledge-based society, the quality of education is the core factor of national development. Above all, for improving educational quality, it is important to advance teacher's quality. Therefore, in order to maintaining high-level quality of education, it is required to select and appoint competent teacher. It deserves emphasis on importance of teacher recruitment test for maintaining high-level quality of education in this changes of age. Specially, Secondary School Teacher Recruitment Test of Electricity Electronics Communication Subject is declined qualitatively as each Subject of Electricity Electronics Communication is integrated and criterion of examination is obscured. This research analyzed The seventh curriculum and curriculum of Institution of Teacher Education of Electricity Electronics Communication Subject and already known examination of it On the basis of analyzing result, A field, proportion and points of examination decided through a expert conference are as follow: first, Teacher Recruitment Test of Electricity Electronics Communication Subject consists of subject pedagogics and contents. a proportion of subject pedagogics is 20% and subject contents is 80%. second, a subfield of subject contents consists of industrial education, industrial curriculum, industrial instruction method, practical guidance method, management of practical field organization, assesment of industrial education, industrial-educational cooperation and vocation and career education. third, subject contents consists of a common special, foundation special and application special field. a common a proportion of special field is 7.4%, foundation special is 20% and application special field which consists of electric field(21.3%), electronic field(21.3%) and communication field(10%) is 52.6%. fourth, Teacher Recruitment Test of Electricity Electronics Communication Subject execute practical technique test after finishing writing test.

• Journal of the Korean Association of Geographic Information Studies
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• v.5 no.1
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• pp.38-47
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• 2002

This paper demonstrates a regional analysis of landslide occurrence potential by applying geographic information system to the Kumi City selected as a pilot study area. The estimate criteria related to natural and humane environmental factors which affect landslides were first established. A slope map and a aspect map were extracted from DEM, which was generated from the contour layers of digital topographic maps, and a NDVI vegetation map and a land cover map were obtained through satellite image processing. After the spatial database was constructed, indexes of landslide occurrence potential were computed and then a few landslide-potential areas were extracted by an overlay method. It was ascertained that there are high landslide-potential at areas of about 30% incline, aspects including either south or east at least, adjacent to water areas or pointed end of the water system, in or near fault zones, covered with medium vegetable. For more synthetic and accurate analysis, soil data, forest data, underground water level data, meteorological data and so on should be added to the spatial database.

• Journal of Software Assessment and Valuation
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• v.16 no.2
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• pp.99-107
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• 2020

An underground integrated map is being built for underground safety management and is being updated periodically. The map update proceeds with the procedure of deleting all previously stored objects and saving newly entered objects. However, even unchanged objects are repeatedly stored, deleted, and stored. That causes the delay of the update time. In this study, in order to shorten the update time of the integrated map, an updated object and an unupdated object are separated, and only updated objects are reflected in the underground integrated map, and a system implementing this technology is described. For the updated object, an object comparison method using the center point of the object is used, and a quad tree is used to improve the search speed. The types of updated objects are classified into addition and deletion using the shape of the object, and change using its attributes. The proposed system consists of update object detection, extraction, conversion, storage, and history management modules. This system has the advantage of being able to update the integrated map about four times faster than the existing method based on the data used in the experiment, and has the advantage that it can be applied to both ground and underground facilities.

• Korean Journal of Environmental Agriculture
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• v.36 no.2
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• pp.119-128
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• 2017

BACKGROUND: Miscellaneous cereal have been largely consumed in Korea as due to their physiological functions beneficial to human health. The cereals are currently a social concern because they have been found to contain heavy metals. Thus, monitoring heavy metals in the cereals is an important requirement for food safety analysis. In this study, we determined arsenic concentration in the cereals randomly harvested from different markets. METHODS AND RESULTS: Inorganic arsenic was determined by ICP-MS coupled with HPLC system. The HPLC-ICP-MS analysis was optimized based on the limit of detection and recover test to reach $0.13-1.24{\mu}g/kg$ and 94.3-102.1%, respectively. The concentrations of inorganic arsenic equivalent to daily exposure were levels of $19.91{\mu}g/day$ in mixed grain, $1.07{\mu}g/day$ in glutinous rice, $0.77{\mu}g/day$ in black brown rice, $0.13{\mu}g/day$ in barley and $0.11{\mu}g/day$ in soybeans. CONCLUSION: The levels of arsenic in miscellaneous cereals were found lower than the recommended The Joint FAO/WHO Expert Committee on Food Additives (JECFA) levels, suggesting that the cereals marketed in Korea are not potential concern in risk assessment.

• Korean Journal of Psychosomatic Medicine
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• v.4 no.1
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• pp.21-36
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• 1996

This study was attempted to investigate reliability and validity of premenstrual assessment form(PAF). PAF was administered to 230 high school students who had reported premenstrual changes. PAF revealed considerable diversity in premenstrual symtom changes of the subjects. The items with most frequent reported premenstrual changes were 21 items out of 95. Cronbach's internal consistency was .95, and test-retest reliability was .80. Validity test was performed by constructional validation analysis. 8 factors(impulsive & unstable factor, depressive factor, withdrawal & social functioning impairment factor, anxiety & cognitive dysfunction factor, physiological factor, general discomfort factor, increased well-being factor, other factor) emerged at factor analysis. Each of them accounted for 33.97, 5.10, 3.70, 2.93, 2.64, 2.46, 2.12, 2.03 of total variance respectively. High school students experienced impulsive & unstable features of premenstrual symptoms more frequently. This study suggests PAF can be a reliable and valid tool as a initial screening and evaluation of premenstrual changes. finally, factor analysis result was compared with PAF typological categories.

• Journal of Korean Society of Forest Science
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• v.97 no.4
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• pp.437-444
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• 2008

This study has intended to evaluate the forest recreation functions to seek methods to designate the recreational areas inside a recreation forest. This study has Mt. Chung-ok in Korea as a study area to which Quantification method II as a valuation measure was applied. This study also has chosen a degree of recreational utility as an external criterion and six factors including Forest type, Forest age, Slope, Riparian area, Road, and Facility for the 173 stands in this area. As a result, absolute discriminated success rate was obtained, so that the first and second estimated correlation ratios were 82% and 74%, respectively. Road and Slope had great influences on the potential power of recreational functions. In the category, recreational function was more influenced by the existence of road and the lower degree of slope. Also, this study has drawn an evaluation map, which displayed the potential power of recreational functions by classifying three discrimination points such as H(High), M(Medium), and L(Low) through calculating the degree of recreational utility of the recreation forest for the stands by applying an estimation formula of recreational function in the stands. This study seems to be worthwhile in terms of actual, experimental, and intuitive interpretation for the degree of recreational utility calculated by using Quantification method theory.