• Journal of the Korean Ceramic Society
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• v.51 no.4
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• pp.317-323
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• 2014

People could not imagine living without tab water. However, the water filtering process at a purification plant used to produce tab water creates tons of sludge, which is generally wasted. This sludge waste consists of (1) mineral elements, such as sand, (2) organic materials, and (3) a coagulant, which agglomerates the two. As an enormous amount of sludge waste is generated every year, numerous studies have been carried out to identify how to deal with this problem. Currently, however, most of the sludge waste is directly discarded in landfills. In the present study, water-purified sludge waste received a heat treatment at $1300^{\circ}C$ and was then ground into particles to be used as a ceramic material. Next, the resultant particles were compounded with chamotte substitutes to produce grogged clay that is suitable for wheel-throwing ceramics. Consequently, the plasticity of the sludge waste decreased as the content of calcination increased. Thus, it is considered that wheel throwing is available only up to PBF-3. Thus, it is available for wheel throwing and has a high strength of 864 $kgf/cm^2$ with less than 0.2 percent of porosity and absorption ratio were displayed in PBF-2 at $1280^{\circ}C$ with 20 percent of calcination from the purified sludge. Therefore, the PBF-2 body produced in this study was considered to be capable of replacing grogged clay in the market.

• The Korea Journal of Herbology
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• v.26 no.3
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• pp.57-63
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• 2011

Objectives : Peucedani Radix ('Jeonho' in Korean) is the root of Peucedanum praeruptorum or Angelica decursiva. However, the root of Anthriscus sylvestris has usually been distributed as Jeonho. This study was performed to determine the discriminative criteria of Jeonho, focused on distribution in Korean markets. Methods : We have determined identification keys to discriminate each Jeonho samples, through observation of external morphology of original plants, and the research of external and internal morphological features of dried Jeonho herbs. Results : Because of identical to the Korean plant name 'Jeonho', Anthrisci Radix had been came into use as a substitute of Jeonho in Korea during the time of Japanese colonial rule. The original plants of Jeonho and its substitute are discriminated with shape of leaf, leaf margin and color of stem. External morphological features of the medicinal herbs of Jeonho are different in the color of cross-sections, pellucid dot, white powder. Internal morphological points, such as fiber bundle of xylem, seconadary mudullary ray and ray of xylem were also used as discriminative criteria for Jeonho. Further details(e.g. identificaion keys) are in the article. Conclusions : We think that these discriminative criteria will be meaningful in identifying the substitutes and adulterants of Jeonho.

• Korean Journal of Materials Research
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• v.27 no.7
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• pp.381-385
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• 2017

In order to replace 14K white gold alloys, the properties of 5K white gold alloys (Au20-Ag80) were investigated by changing the contents of In (0.0-10.0 wt%). Energy dispersive X-ray spectroscopy (EDS) was used to determine the precise content of alloys. Properties of the alloys such as hardness, melting point, color difference, and corrosion resistance were determined using Vickers Hardness test, TGA-DTA, UV-VIS-NIR-colorimetry, and salt-spray tests, respectively. Wetting angle analysis was performed to determine the wettability of the alloys on plaster. The results of the EDS analysis confirmed that the Au-Ag-In alloys had been fabricated with the intended composition. The results of the Vickers hardness test revealed that each Au-Ag-In alloy had higher mechanical hardness than that of 14K white gold. TGA-DTA analysis showed that the melting point decreased with an increase in the In content. In particular, the alloy containing 10.0 wt% In showed a lower melting temperature (> $70^{\circ}C$) than the other alloys, which implied that alloys containing 10.0 wt% In can be used as soldering materials for Au-Ag-In alloys. Color difference analysis also revealed that all the Au-Ag-In alloys showed a color difference of less than 6.51 with respect to 14K white gold, which implied a white metallic color. A 72-h salt-spray test confirmed that the Au-AgIn alloys showed better corrosion resistance than 14K white gold alloys. All Au-Ag-In alloys showed wetting angle similar to that of 14K white gold alloys. It was observed that the 10.0 wt% In alloy had a very small wetting angle, further confirming it as a good soldering material for white metals. Our results show that white 5K Au-Ag-In alloys with appropriate properties might be successful substitutes for 14K white gold alloys.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.40 no.2
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• pp.104-110
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• 2017

When evaluating effectiveness of a R&D program, there is a tendency to simply compare the performances of the beneficiaries before and after the program or to compare the differences in the performances of the beneficiaries and the non-beneficiaries before-after the program. However, these ways of evaluating effectiveness of a program have some problems because they can not differentiate between complement effect, which facilitates corporate R&D investment, and substitute effect, which, literally, substitutes corporate R&D investment. Therefore, these problems could bring about wrong policies concerning R&D programs. In this paper, a new approach using path analysis is suggested as a means to overcome these problems and it is utilized, as an application, to evaluate the effectiveness of Plant Engineering Program conducted by Ministry of Trade, Industry & Energy, Korea. First, the direct impact of government R&D investment on corporate R&D investment is analyzed, through which it is identified which of crowding-in effect (complement effect) and crowding-out effect (substitute effect) is dominant. Next, the direct effect of government R&D investment on corporate performance and the direct effect of corporate R&D investment on corporate performance is analyzed respectively. Finally, by combining the two previous analysis, the total effect of government R&D investment on corporate performance is identified. As a result, it turns out that, in Plant Engineering Program, crowding-in effect is more dominant than crowding-out effect and that Plant Engineering Program has definitely positive effect on the beneficiary in terms of corporate performance indirectly and directly.

• Journal of the East Asian Society of Dietary Life
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• v.15 no.4
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• pp.397-404
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• 2005

The propose of this study was to investigate taurine intake in formula-fed and breast-fed infants and to estimate the level of taurine of blood and urine in order to determine the requirement of taurine intake in infants. These results will be useful to suggest the guideline of requirement of taurine intake and may contribute toward the proper use of breast milk substitutes. Experimental groups were breast-fed infants (n=10) and formula-fed infants (n=10) of 20 normal delivery infants in general hospital. This study was longitudinal study from birth up to 16weeks (0 week, 4 weeks, 8 weeks, 12 weeks, 16 weeks). The items of test were anthropometry(weight, height, head circumference, chest circumference), intake of taurine, taurine level of blood and urine in breast-fed and formula-fed infants. There were no significant differences between breast-fed and formula-fed infants in weight, height, head and chest circumference. There is a need for future studies of exclusive infants with larger samples to determine which growth pattern should be considered as the norm. Taurine concentration of plasma and urine did not differ between breast-fed and formula-fed infants. Taurine intake recommendations for infants is about 30mg/day from this study. This data will be useful for production of human-like formula milk and suggestion of an index of selection of a consumer in taurine.

• KIISE Transactions on Computing Practices
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• v.21 no.3
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• pp.173-182
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• 2015

Motion control systems are widely deployed in various industrial automation processes. The motion controller, which is a key element of motion control systems, has stringent real-time constraints. The controller must provide a short and deterministic control message transmission cycle, and minimize the actuation deviation among motor drives. To meet these requirements, hardware-based proprietary controllers have been prevalent. However, since it is becoming difficult for such an approach to meet increasing needs of system interoperability and scalability, nowadays, software-based universal motion controllers are regarded as their substitutes. Recently, embedded motion controller solutions are gaining attention due to low cost and relatively high performance. In this paper, we designed and implemented an embedded motion controller on an ARM-based evaluation board by using Xenomai real-time kernel and other open source software components. We also measured and analyzed the performance of our embedded controller under a realistic test-bed environment. The experimental results show that our embedded motion controller can provide relatively deterministic performance with synchronized control of three motor axis at 2 ms control cycle.

• Korean Journal of Plant Resources
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• v.19 no.5
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• pp.563-572
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• 2006

The plant Rubus species (Rosaceae) mainly contains $19{\alpha}-hydroxyurane-type$ triterpenoids $(19{\alpha}-HUT)$ as bioactive components. Available functional food includes blackberry (the fruit of thornless Rubus sp.), red raspberry (R. idaeus) and black raspberry (R. occidentalis). However, the fruit of R. coreanus, which is used in Korea as a functional food, substitutes black raspberry. Rubi Fructus, which has been traditionally used as an oriental medicinal drug, designates only unripe fruit of R. coreanus but not its ripe fruit which indicates that it needs high content of $19{\alpha}-HUT$ as a crude drug. Throughout our experiment, we found that ripe fruits contain very little amount of $19{\alpha}-HUT$ when compared to unripe fruits. In addition, various and rich $19{\alpha}-HUT$ has been reported from Rubus species. The most common structure of $19{\alpha}-HUT$ of Rubus species, euscaphic acid or tormentic acid with $3{\alpha}-OH$ or $3{\beta}-OH$, respectively, can be glycosylated or oxidized to produce a number of $19{\alpha}-HUTs $as euscaphic acid and tormentic acid derivatives and even esterified to form dimeric triterpenoids. In this review, the bioactivity and biosynthetic pathway and chemical characterization of $19{\alpha}-HUTs$ found in Rubus species are discussed.

• Elastomers and Composites
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• v.44 no.2
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• pp.106-111
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• 2009

Tissue engineering is a research field for artificial substitutes to improve or replace biological functions. Scaffolds play a important role in tissue engineering. Scaffold porosity and pore size provide adequate space, nutrient transportation and cell penetration throughout the scaffold structure. Scaffold structure is directly related to fabrication methods. This review will introduce the current technique of 3D scaffold fabrication for tissue engineering. The conventional technique for scaffold fabrication includes salt leaching, gas foaming, fiber bonding, phase seperation, melt moulding, and freeze drying. These conventional scaffold fabrication has the limitations of cell penetration and interconnectivity. In this paper, we will present the solid freeform fabrication (SFF) such as stereolithography (SLA), selective laser sintering (SLS), and fused deposition modeling (FDM), and 3D printing (3DP).

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.434-436
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• 2013

Ga-doped ZnO (GZO) was substitutes of the SnO2:F films on soda lime glass substrate in the photovoltaic devices such as CIGS, CdTe and DSSC due to good properties and low cost. However, it was reported that the electrical resistivity of GZO is unstable above $300^{\circ}C$ in air atmosphere. To improve thermal stability of GZO thin films at high temperature above $300^{\circ}C$ an $TiO_2$ thin film was deposited on the top of GZO thin films as a barrier layer by Pulsed Laser Deposition (PLD) method. $TiO_2$ thin films were deposited at various thicknesses from 25 nm to 100 nm. Subsequently, these films were annealed at temperature of $300^{\circ}C$, $400^{\circ}C$, $500^{\circ}C$ in air atmosphere for 20 min. The XRD measurement results showed all the films had a preferentially oriented ( 0 0 2 ) peak, and the intensity of ( 0 0 2 ) peak nearly did not change both GZO (300 nm) single layer and $TiO_2$ (50 nm)/GZO (300 nm) double layer. The resistivity of GZO (300 nm) single layer increased from $7.6{\times}10^{-4}{\Omega}m$ (RT) to $7.7{\times}10^{-2}{\Omega}m$ ($500^{\circ}C$). However, in the case of the $TiO_2$ (50 nm)/GZO (300 nm) double layer, resistivity showed small change from $7.9{\times}10^{-4}{\Omega}m$ (RT) to $5.2{\times}10^{-3}{\Omega}m$ ($500^{\circ}C$). Meanwhile, the average transmittance of all the films exceeded 80% in the visible spectrum, which suggests that these films will be suitable for photovoltaic devices.

• The Journal of Korean Medicine
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• v.20 no.4
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• pp.16-22
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• 2000

This study intends to report the significance of several experimental results obtained from analysing the genes extracted from the plants and herbal medicine such as P. temalta (Thunb.) Breit, A. amurense var serratum Nakai, A. erubescens (Wall.) Schott, Pinelliae Tuber and Arisaematis Tuber, mainly by the method of RAPD(randomly amplified polymorphic DNA) and the method of RFLP(restriction fragment length polymorphism) on ITS(internal transcribed spacer) region. Genomic DNA could be extracted from both original plants and dried materials. DNA fragments of P. temata kind and A. amurense kind showed the same aspect separately within the same species under the method of RAPD using random primer, while various aspects(polymorphism) were discovered among different species. In RAPD analysis by uniprimer, common bands were extracted from all types of P. temata in the case of uniprimer #4, which were distinguished from the kind of A. amurense. Other polymorphic bands appeared in between different A. amurense species as well. In the case of uniprimer #11, particular band came out in the kind of P. temata. On the other hand, in the case of uniprimer #5, #6, and #8, various bands(polymorhism) were revealed in both kinds of P. temata and A. amurense. Although further study is needed to ascertain whether these results are due to the differences of species, kinds, or growing place, the results could be used as a scientific method of identifying the substitutes for A. amurense genus. The author believes that as if P. temata class of plants used in this experiment are different among themselves in terms of the shape, size and property, those are clearly a class of P. temata or belong to the same genus.