• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.3124-3124
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• 2001

The development and evolution of near infra-red spectroscopic (NIS) calibrations for high-moisture materials is an expensive proposition. Such investment is suspect unless the instrument, or instruments, on which calibrations were developed can be preserved intact or re-standardized as component replacements occurs. The objective of this paper is to detail the changes in performance of a six-year old instrument after maintenance in years five and six resulted in collection of spectral data that was increasingly removed from the calibration population. Calibrations for the analysis of mature sugarcane stalks, a high-moisture material, were developed successfully in 1995 using a broad sample population in terms of genetics, and spectral and temporal variation. The spectral library was further broadened in 1996. In 1997, 1999, 1999, and 2000, additional samples constituting 10% of the laboratories throughput were subjected to full component analyses using routine laboratory techniques. These samples were primarily random samples, but were complemented with samples that were significant for the spectral H statistic or for the component t statistic. In 1998, an additional calibration was developed for populations consisting of samples of either mature stalks (culms) or sucker culms. Substantial additional samples numbers were collected for this calibration in 1999 and 2000. Attempts to standardize the scanning spectrophotometer used for these calibrations with a second similar instrument in 1999 failed because the instruments were optically different, and standardization could not account for this. Maintenance adjustments were made to the remote reflectance probe of the original instrument in 1999, and replacement of its PbS detectors was done in 2000. Spectral data collected in 1999 and 2000 yielded spectral populations that were increasingly removed from the respective spectral populations on which the calibrations were developed. The mature stalk calibrations benefited marginally from evolutionary calib.

• Journal of Ocean Engineering and Technology
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• v.25 no.6
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• pp.91-96
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• 2011

In this paper, friction welded joints were constructed to investigate the mechanical properties of welded 15-mm diameter solid bars of Mg alloy (AZ31B). The main friction welding parameters were selected to endure reliable quality welds on the basis of visual examination, tensile tests, impact energy test, Vickers hardness surveys of the bonds in the area and heat affected zone (HAZ), and macrostructure investigations. The study reached the following conclusions. The tensile strength of the friction welded materials (271 MPa) was increased to about 100% of the AZ31B base metal (274 MPa) under the condition of a heating time of 1 s. The metal loss increased lineally with an increase in the heating time. The following optimal friction welding conditions were determined: rotating speed (n) = 2000 rpm, heating pressure (HP) = 35 MPa, upsetting pressure (UP) = 70 MPa, heating time (HT) = 1 s, and upsetting time (UT) = 5 s, for a metal loss (Mo) of 10.2 mm. The hardness distribution of the base metal (BM) showed HV55. All of the BM parts showed levels of hardness that were approximately similar to friction welded materials. The weld interface of the friction welded parts was strongly mixed, which showed a well-combined structure of macro-particles without particle growth or any defects. In addition, an acoustic emission (AE) technique was applied to derive the optimum condition for friction welding the Mg alloy nondestructively. The AE count and energy parameters were useful for evaluating the relationship between the tensile strength and AE parameters based on the friction welding conditions.

• Journal of the Korean Recycled Construction Resources Institute
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• v.5 no.3
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• pp.313-319
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• 2017

In general, various factors such as grain size, chemical composition, amorphous amount, amorphous Si and Al content of fly ash affect the reaction with cement. In this study, we investigate the effect of fly ash particle characteristics on compressive strength. The standard sand was pulverized to a particle size similar to that of fly ash and the compressive strength was measured by blending with the cement as in fly. Using the measured compressive strength results, strength enhancement by cement hydration reaction and strength enhancement by particle filling effect were confirmed. Strength increment by pozzolanic reaction of fly ash was calculated by using the compressive strength results of mortar substituted with standard powder. As a result of comparison between compressive strengths and the particle characteristics of fly ash, the blaine showed a weak correlation with the compressive strength and the PI(Pozzolanic Index) showed good correlation with the 10% penetration diameter(D10) and the 50% Respectively. Therefore, it is expected that PI will be a good means to evaluate the fly ash characteristics together with the chemical characteristics of fly ash.

• Journal of the Korean Society for Advanced Composite Structures
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• v.1 no.3
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• pp.41-48
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• 2010

In this paper, the analysis of impact damage behavior of a reinforced concrete structure that undergoes both a shock impulsive loading and an impact loading due to the air blast induced from an explosion is performed. Firstly, a pair of multiple loadings are selected from the scenario that an imaginary explosion accident is assumed. The RC structures strengthened with advanced composite materials (ACM) are considered as a scheme for retrofitting RC wall structures subjected to multiple explosive loadings and then the evaluation of the resistant performance against them is presented in comparison with the result of the evaluation of a RC structure without a retrofit. Also, in order to derive the result of the analysis similar to that of real explosion experiments, which require the vast investment and expense for facilities, the constitutive equation and the equation of state (EOS) which can describe the real impact and shock phenomena accurately are included with them. In addition, the numerical simulations of two concrete structures are achieved using AUTODYN-3D, an explicit analysis program, in order to prove the retrofit performance of a ACM-strengthened RC wall structure.

• Journal of the Korean Society of Costume
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• v.59 no.3
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• pp.145-156
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• 2009

This study proposes the product development through an organic link with multi-faceted analysis on the archetype of traditional costumes culture. In order to find ways to develop cultural products, Jogakbo was selected, and the research result is as following. 1. Analysis on the types of Jogakbo products sold in the market shows that there are not only living, stationary, and fashion items, but also DIY packages. In terms of materials used, most of these Jogakbo products were made of fabric or mixture of different materials. These products displayed similar tendency by reflecting formative characteristics of Jogakbo. 2. This study analyzed the color, surface composition, material, manufacturing, and usage of Jogakbo. The rotor of Jogakbo is mostly composed of mono tone colors or Obangsac(five-element colors). The mono tone colors carries environmentally friendly meaning as it is using the natural color and Obangsac means harmony. Moreover, the surface composition of Jogakbo represents the expansion through connection and its material is also meaningful in that it is recycling. Manufacturing of Jogakbo has educational significance, fortune-wishing characteristics, decorative function, it also gives a gratification of handcraft. The usage of Jogakbo is a multi-(unctional article whose form is determined by an item that is held inside it. 3. Through the analysis on Jogakbo, this study presents the baby wear in relation to the ere-friendliness of colors, brooch sets using the surface composition, dresses using recycling fabric, children's educational instruments with educational significance, as well as multi-functional packages in regards to usage of Jogakbo.

• Korean Institute of Interior Design Journal
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• v.24 no.6
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• pp.3-12
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• 2015

Recently, the spatial design of resting spaces in department stores has been changed. The design elements such as colors, materials, lighting, natural elements, furniture arrangement, and VMD are not only providing a pleasant and natural indoor atmosphere in resting spaces but also providing various services to customers. In this study, it aims to analyze how the spatial design characteristics of resting spaces in department stores are appeared. The results are as follows. First, the spatial characteristics of the resting spaces in department sores came up as five factors; accessibility, recognition, comfort, convenience, and esthetics. As the result, the accessibility is the most important factor in resting spaces. Second, the resting spaces was well located near by the elevators and escalators providing easy accessibility to customers to floor. Third, the resting spaces need to improve the spatial design for emphasizing the recognitions by using colors, materials and lighting. Fourth, the resting spaces were provided different atmosphere by their location. Fifth, the various forms of furniture, curved, zigzagged, and cubed, were placed in the resting spaces for comport use. Sixth, the aesthetic was the least important factor of all. To improve this problem, the resting spaces need to provide cultural contents by installing art pieces, moving picture facilities, and VMD. Seven, most of the resting spaces had similar floor plan type that they did not perform their role successfully. The resting spaces need to provide both individual rooms and unique open spaces for giving a choice to use when customers visit them.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.38 no.6
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• pp.691-698
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• 2014

This paper describes the manufacturing processes for a flexbeam and torque tube made of composite materials, along with the procedures for testing their basic properties. A flexbeam and torque tube can be considered to be key structural components of a bearingless rotor hub system. A hinge offset effect can be realized by a large elastic deformation and twist of the flexbeam, and the blade pitch control forces are transferred by the rotation of the torque tube. The basic property tests included bending and twist tests to determine the flap stiffness, lag stiffness, and torsion stiffness of the flexbeam, torque tube, and blade, and these tests were performed prior to starting the whirl tower test. In addition, the estimated results were compared with experimental data, and the calculations were found to be a good match for the analysis results and had a similar tendency. Through these results, we could confirm that a flexbeam and torque tube made of composite materials satisfied the structural stiffness requirements.

• Journal of Electrical Engineering and Technology
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• v.12 no.4
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• pp.1605-1610
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• 2017

The electrochemical luminescence (ECL) device was investigated, which has similar structure to the dye-sensitized solar cell. The structure of the ECL cell in this experiment reliably induces a large amount of the oxidation around electrodes. The band gap of the ECL electrode is of 3.0 - 3.2 eV. Titanium dioxide ($TiO_2$) nanoparticle has following properties: a band gap of 3.4 eV, a low-priced material, and 002 preferred orientation (Z-axis). Zinc Oxide (ZnO) nanorod is easy to grow in a vertical direction. In this paper, in order to determine material suitable for the ECL device, the properties of various materials for electrodes of ECL devices such as ZnO nanorod (ZnO-NR) and $TiO_2$ nanoparticle ($TiO_2-NP$) were compared. The threshold voltage of the light emission of the ZnO-NR was 2.0 V which is lower than 2.5 V of $TiO_2-NP$. In the other hand, the luminance of $TiO_2-NP$ was $44.66cd/m^2$ and was higher than that of $34cd/m^2$ of ZnO-NR at the same applied voltage of 4 V. Based on the experimental results, we could conclude that $TiO_2-NP$ is a more suitable electrode material in ECL device than the ZnO-NR.

• Journal of The Korean Society of Grassland and Forage Science
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• v.16 no.1
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• pp.61-68
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• 1996

Hehage production, botanical composition and soil chemical characteristics were investigated Ween new pastures and old pastures during grazing seasons from May 1993 to October 1994, to find out the condition of pastures grazed by horses on Chdu. Dry matter yields between new pastures and old pastures were 8,757kglha and 7,486kglha respectively. Plant heights of new pastures were 17.4cm. compared with those of old pastures of 12.lcm. The botanical composition of new pastures was composed of grasses about 402, legumes 7~14%, others 18-30% and dead materials 18~ 25%. whiie there were grasses 12%, legumes 3~7%, others 65% and dead materials 15% in old pastures. The contents of crude protein, phosphoms and sodium were lower in old pastures(l3.30, 0.24 and 0.10% respectively) than those in new pastures(l5.47, 0.28 and 0.14% respectively). There was no difference in ADF, NDF, Ca, Mg and K content between the 2 kinds of pastures. The chemical characteristics of the 2 kinds of pastures was shown to be similar, except available phosphorus, comparing 8.18ppm in old pastures with 84.43ppm in new pastures. Although the herbage yield and the soil characteristics of old pastures were lower than those of new pastures, we suppose that the old pastures would be improved, if taken good care of by methods such as oversowing and sometimes applying fertilizer.

• Fisheries and Aquatic Sciences
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• v.14 no.1
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• pp.43-54
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• 2011

Gene structure of copper/zinc-superoxide dismutase (Cu/Zn-SOD; sod1) was characterized in Hemibarbus mylodon (Teleostei; Cypriniformes), an endangered freshwater fish species in Korean peninsula. Full-length cDNA of H. mylodon SOD1 consisted of a 796-bp open reading frame sequence encoding 154 amino acids, and the deduced polypeptide sequence shared high sequence homology with other orthologs, particularly with regard to metal-coordinating ligands. Genomic structure of the H. mylodon sod1 gene (hmsod1; 1,911 bp from the ATG start codon to the stop codon) was typical quinquepartite (i.e., five exons interrupted by four introns); the lengths of the exons were similar among species belonging to various taxonomic positions. The molecular phylogeny inferred from sod1 genes in the teleost lineage was in accordance with the conventional taxonomic assumptions. 5'-flanking upstream region of hmsod1, obtained using the genome walking method, contained typical TATA and CAAT boxes. It also showed various transcription factor binding motifs that may be potentially involved in stress/immune response (e.g., sites for activating proteins or nuclear factor kappa B) or metabolism of xenobiotic compounds (e.g., xenobiotic response element; XRE). The hmsod1 transcripts were ubiquitously detected among tissues, with the liver and spleen showing the highest and lowest expression, respectively. An experimental challenge with Edwardsiella tarda revealed significant upregulation of the hmsod1 in kidney (4.3-fold) and spleen (3.1-fold), based on a real-time RT-PCR assay. Information on the molecular characteristics of this key antioxidant enzyme gene could be a useful basis for a biomarker-based assay to understand cellular stresses in this endangered fish species.