• Geomechanics and Engineering
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• v.4 no.3
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• pp.219-227
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• 2012

Pavement management systems require systematic monitoring of pavement surfaces to determine preventive and corrective maintenance. The process involves the accumulation of large amounts of visual data, typically obtained from site visitation. The pavement surface condition is then correlated to a pavement distress index that is based on a scoring system previously established by state or federal agencies. The scoring system determines if the pavement section requires maintenance, overlay or reconstruction. One of the surface distresses forming part of the overall pavement distress index is the Alligator Crack Index (AC Index). The AC Index involves the visual evaluation of the crack severity of a section of a pavement as being low, medium, or high. This evaluation is then integrated into a formula in order to obtain the AC Index. In this study a quantification of the visual evaluation of the severity of alligator cracking is carried out using photographs and the fractal dimension concept from fractal theory. Pavements with low levels of cracking were found to have a fractal dimension equal to 1.051. Pavements with moderate levels of cracking had a fractal dimension equal to 1.1754. Pavements with high degrees of cracking had a fractal dimension that varied between 1.5037 (high) and 1.7111 (very high). Pavements with a level of cracking equal to 1.8976 represented pavements that disintegrated and developed potholes. Thus, the visual evaluation of the state of cracking of a pavement (the AC Index) could be enhanced with the use of the fractal dimension concept from fractal theory.

• Korean journal of food and cookery science
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• v.25 no.5
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• pp.564-574
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• 2009

This study was conducted to evaluate the effects of the LOHAS index value of school food service employees on the purchase of food materials and foodservice quality. The subjects consisted of 566 foodservice employees. The findings were as follows. (1) The foodservice employee's LOHAS index fell within that of a NOMADICS group with an average of 72.18 points out of 100 points. (2) When the age, working experience and LOHAS index of the foodservice employees was high, the necessity, view, interest and recognition of LOHAS introduction for the improvement of the foodservice environment was high. (3) The amount of environmentally-friendly food materials purchased by foodservice employees was high, when they had a high LOHAS index. (4) High foodservice quality management items of foodservice employees were 'sanitation management' (3.87 points) and 'human resource management' (3.84 points), whereas 'menu management' (3.57 points) and 'food material and inspection management' (3.61 points) scored low. (5) The LOHAS index of foodservice employees has a significant impact on the purchase intention of environmentally-friendly food materials in LOHAS and NOMADICS groups. (6) This study confirmed that a higher LOHAS index of foodservice employees was associated with higher foodservice quality management behavior, which leads to an improved quality of foodservice.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.141-141
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• 2013

Shape control of metal nanocrystals has broad applications, including catalysis, plasmonics, and sensing. It was found that controlling the atomic arrangement on metal nanocrystal surfaces affects many properties, including the electronic dipole or work function. Tuning the surface structure of exposed facets of metal nanocrystals was enabled by shape control. We investigated the effect of shape on nanomechanical properties, including friction and adhesion forces. Two nanoparticles systems, high-index {321} and low-index {100}, were used as model nanoparticle surfaces. Scanning force microscopy was used to probe nanoscale friction and adhesion. Because of the abundant presence of high-density atomic steps and kinks, high-index faceted nanoparticles have a higher surface energy than low-index faceted cubic nanoparticles. Due to this high surface energy, high-index faceted particles have shown stronger adhesion and higher friction than low-index nanoparticles. We discuss the results in light of the differences in surface energy as well as the effect of capping layers in the measurement.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.7
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• pp.293-300
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• 2016

Traditional databases exploit a record-based model, where the attributes of a record are placed contiguously in a slow hard disk to achieve high performance. On the other hand, for read-intensive data analysis systems, the column-based compressed database has become a proper model because of its superior read performance. Currently, flash memory SSD is largely recognized as the preferred storage media for high-speed analysis systems. This paper introduces a compressed column-storage model and proposes a new index and its data management scheme for a high-capacity data warehouse system. The proposed index management scheme is based on the asymmetric index duplication and achieves superior search performance using the master index and compact index, particularly for large read-mostly databases. In addition, the data management scheme contributes to the read performance and high reliability by compressing the related columns and replicating them in two mirrored SSD. Based on the results of the performance evaluation under the high workload conditions, the data management scheme outperforms the traditional scheme in terms of the search throughput and response time.

• Clinical and Experimental Pediatrics
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• v.57 no.2
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• pp.79-84
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• 2014

Purpose: Overweight can be defined by the body mass index (BMI) and is likely associated with an increased cardiovascular disease risk. However, waist circumference (WC), a central adiposity index, may be a better indicator of cardiovascular disease risk. Studies comparing the effects of BMI and WC on cardiovascular risk factors, such as high blood pressure (BP), are rare in adolescents. Methods: We analyzed the correlations of BMI and WC with BP in 3,363 Korean adolescents (aged 10-19 years), using data from the Korean National Health and Nutrition Examination Surveys (2009-2011). Results: Systolic BP (SBP) in both sexes and diastolic BP (DBP) in boys were higher in the high BMI (>85th percentile) and high WC (>90th percentile) groups. High BMI and high WC were positively correlated with high SBP (>90th percentile) in both sexes, and high DBP (>90th percentile), in boys. BMI maintained its positive associations with SBP, DBP, high SBP, and high DBP in the normal weight ($BMI{\leq}85th$ percentile) and overweight (BMI>85th percentile) groups in both boys and girls, as well as in all subjects of both sexes, even after adjustment for WC. However, WC did not correlate with SBP, DBP, high SBP, or high DBP after adjustment for BMI in any group in either sex. Conclusion: In Korean adolescents, BMI correlated better with BP and high BP levels than WC. Further, BMI was positively associated with BP and high BP in the normal weight group as well as in the overweight group.

• Bulletin of the Korean Chemical Society
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• v.30 no.5
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• pp.1177-1180
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• 2009

• Korean Journal of Agricultural Science
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• v.45 no.4
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• pp.871-878
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• 2018

The government of Gyeongbuk in Korea increased the financial input in the agricultural sector by 43% from 2008 through 2012. However, the productivity of the agricultural sector in Gyeongbuk rose only about 3.6% during the same period. This study evaluated the agricultural competitiveness of each city or county in Gyeongbuk using six evaluation indices (scale, productivity, finance input, location quotient, technical education, and total) and investigated the relationship between the indices and total values of agricultural productions. The results show that Sangju, Gyeongju, Andong, Uiseong, and Seongju have high competitiveness for the scale index. For the productivity index, Gimcheon, Mungyeong, Ulleung, Yeongju, and Seongju were highly evaluated. For the location quotient index, Yeongcheon, Uiseong, Cheongdo, Seongju, and Sangju have high competitiveness. Uiseong, Yeongdeok, Cheongsong, Gunwi, and Yeongyang were highly evaluated for the agricultural finance input index. For the agricultural technical education index, Chilgok, Sangju, Mungyeong, Uiseong, and Gyeongju have high competitiveness. Finally, Sangju, Euiseong, Yeongcheon, Gyeongju, and Andong were highly evaluated for the total competitive index, while Yeongdeok, Yeongyang, Goryeong, Uljin, and Cheongsong have a low competitiveness for the total competitive index. This study also found that out of five indices, scale, location quotient, and technical education indices have a positive and statistically significant effect on the total values of agricultural production. However, we did not find any statistically significant effect of the productivity and finance input indices on the total values of agricultural production. Hence, we can conclude that the government should focus their agricultural policy on scale, location quotient and education to improve total agricultural production.

• Bulletin of the Korean Chemical Society
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• v.33 no.8
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• pp.2494-2498
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• 2012

Preparation of several new spirocyclic mercapto derivatives is described. Thiol protection on multi-carbonyl compounds allows of high sulfur content necessary to induce high refractive index. Condensation of 1,3-dimercapto-2-propanol and cyclohexanone followed by successive oxidation and thioacetalization affords a dispirocycle with four sulfurs. Selective S,S-protection of cyclohexane-1,4-dione is achieved with 1,3-dimercapto-2-propanol and 2,3-dimercapto-1-propanol to provide dispirocycles with four sulfurs. Olefine-oxidation of norbornene gives a useful dialdehyde intermediate which is transformed to 1,3-dithiolane for a linearly-bound-cyclic molecule. Refractive index of linearly-bound-cycles was below 1.60 and dispirocycles exhibited high refractive index of 1.57-1.69.

• Korean Journal of Materials Research
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• v.13 no.11
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• pp.717-720
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• 2003

Heavily $p^{ ＋}$-typed ($10^{20}$ $cm^{-3}$ ) GaAs epilayers have been grown on high-index GaAs substrates with various crystallographic orientations from (100) to (111)A by a low-pressure metalorganic chemical vapor deposition. Carbon (C) tetrabromide (CBr$_4$) was used as a C source. At moderate growth temperatures and high V/III ratios, the hole concentration of C-doped GaAs epilayers shows the crystallographic orientation dependence. The bonding strength of As sites on a growing surface plays an important role in the C incorporation into the high-index GaAs substrates.

• Proceedings of the Safety Management and Science Conference
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• 2009.04a
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• pp.337-350
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• 2009

Using the Malmquist productivity index, this paper compares the productivity of Korean manufacturing industries from 1999 to 2006. The malmquist productivity index has more advantages than previous methods such as solow model, endogenous growth theory. The malmquist productivity index can be decomposed productivity into two parts. The first part is an index of the technical efficiency change. This index has high value when the elements of production is used more efficiently. The second part is an index of technical change. This index has high value if the advent of new technology and process innovation occur.