• Korean Journal of Materials Research
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• v.2 no.6
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• pp.408-416
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• 1992

Stable TiS$i_2$was formed by RTA on single-Si and on poly-Si. Subsequently, an Al-1% Si layer with 600-nm thick was deposited on top of the TiS$i_2$, Finally, the specimens were annealed for 30min at 400-60$0^{\circ}C$in $N_2$ambient. The thermal stability of Al-1% Si/TiS$i_2$bilayer and interfacial reaction were investigated by measuring sheet resistance, Auger electron spectroscopy (AES), and scanning electron microscopy (SEM). The composition and phase of precipitates formed by the reaction of Al-1% Si with Ti-silicide were studied by energy dispersive spectroscopy (EDS), X-ray diffraction (XRD). In the case of single-Si substrate the reaction of Al-1% Si layer with TiS$i_2$layer resulted in precipitates, consuming all TiS$i_2$layer at 55$0^{\circ}C$. On the other hand, the disappearance of TiS$i_2$on poly-Si occurred at 50$0^{\circ}C$ and more precipitates were formed by the reaction of Al-1% Si/TiS$i_2$on potty-Si substrate than those of the reaction on single-Si substrate. This phenomenon resulted from the fact that Ti-silicide formed on poly-Si was more unstable than on single-Si by the effect of grain boundary. By EDS analysis the precipitates were found tobe composed of Ti, Al, and Si. X-ray diffraction showed the phase of precipitates to be theT$i_7$A$l_5$S$i_12$ternary compound.

• Journal of Korean Home Economics Education Association
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• v.17 no.2
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• pp.197-219
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• 2005

This study attempted, in accordance with the National Educational Curriculum, to develop achievement assessment standards for a course within the field of home economics which has been widely adopted by Korean vocational high schools, namely, the food and nutrition subject. Focus was also placed on strengthening the management of the curriculum for this food and nutrition course, as well as on establishing proper assessment standards by developing model assessment tools which can be used to assess the subject. The results of this study can be summarized as follows : First, based on an analysis of the related literature and materials. the desired notion of the achievement and assessment standards was established, and their significance ascertained the achievement and assessment standards for the food and nutrition course were set and the type of model assessment tool which should be developed, as well as the method in which it should be applied. was established Second. by analyzing the curriculums and the contents of the textbooks used in the food and nutrition subject, the researcher was able to compile the 70 factors which could to be used to develop the achievement and assessments standards, and then classify these into 6 main categories and 32 sub-categories. Based on the characteristics of these factors and learners' academic performance levels the number of factors was expanded to 89 in order to establish the achievement standards. In turn, these achievement standards were used, in accordance with the learners' achievement and teaming activity levels, to develop three different levels of assessment standards. namely, upper, middle, and lower ones. Third. a model assessment tool was developed which could be used by individual school units as a reference in terms of achievement and assessment standards, and that could be modified to meet each school's circumstances. In order to create the model assessment tool a 100-question questionnaire was formulated that contained various types of questions, such as essay, report, theoretical and practical, portfolio, as well as multiple choice-type questions. Lastly, the researcher introduced measures to effectively use the achievement and assessment standards developed for the food and nutrition course, as well as the model assessment tool in school units.

• Journal of the Korean Institute of Landscape Architecture
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• v.46 no.2
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• pp.27-36
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• 2018

This study suggests the necessity of behavior analysis as changes to a park environment to reflect user desires can be implemented only by grasping the needs of park users. Online data (blog) were defined as the basic data of the study. After collecting data by 5 - year units, data mining was used to derive the characteristics of the time series behavior while the significance of the online data was verified through social network analysis. The results of the text mining analysis are as follows. First, primary results included 'walking', 'photography', 'riding bicycles'(inline, kickboard, etc.), and 'eating'. Second, in the early days of the collected data, active physical activity such as exercise was the main factor, but recent passive behavior such as eating, using a mobile phone, games, food and drinking coffee also appeared as a new behavior characteristic in parks. Third, the factors affecting the behavior of park users are the changes of various conditions of society such as internet development and a culture of expressing unique personalities and styles. Fourth, the special behaviors appearing at Olympic Park were derived from educational activities such as cultural activities including watching performances and history lessons. In conclusion, it has been shown that people's lifestyle changes and the behavior of a park are influenced by the changes of the various times rather than the original purpose that was intended during park planning and design. Therefore, it is necessary to create an environment tailored to users by considering the main behaviors and influencing factors of Olympic Park. Text mining used as an analytical method has the merit that past data can be collected. Therefore, it is possible to form analysis from a long-term viewpoint of behavior analysis as well as to measure new behavior and value with derived keywords. In addition, the validity of online data was verified through social network analysis to increase the legitimacy of research results. Research on more comprehensive behavior analysis should be carried out by diversifying the types of data collected later, and various methods for verifying the accuracy and reliability of large-volume data will be needed.

• Journal of the Korean Institute of Landscape Architecture
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• v.45 no.3
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• pp.66-79
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• 2017

In 2014, a Donghak Peasant Revolution Memorial Park design competition was held with various forms and techniques to convey mourning. This is a process of the reconsideration of memorial projects that are used to stimulate the collective memory and it is a meaningful resource for examining the consciousness of contemporary designers in regards to the memorial designs that are currently under planning in Korea. This study investigated the background of the Donghak commemorative projects that took place at the same site in a timely manner and analyzed the design competition through the existing literature research. Through this, it was seen that the memorial, which was formed by means of past political purposes, has changed into a way to collect various opinions and forms through open design competition. A framework of analysis prepared through multi-layer analysis is daily use, interaction and spontaneity, abstraction, temporality, locality, integration and harmony with surroundings. The results of this study are as follows. First, in order to convey memorial commemoration in everyday life, the projects organized scattered memorial spaces with special characteristics and linked them with daily activities program. Second, the projects used direct participation and emotional experiences to interact with monuments. Third, color, vertical elements, clustering, and park frame manipulation were used for abstract reproduction. Fourth, the projects introduce architecture and furniture that can be changed and plants for temporal change. Fifth, the previous terrain was restored and the setting of the scene was reproduced in order to make the site a space with place. Sixth, to improve the connection with existing monuments, the projects used techniques such as relaxation and the reinforcement of circulation lines and axes. Seventh, a path and a building conforming to the terrain were arranged for harmony with the surroundings.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.10 no.1
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• pp.1-9
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• 1977

The purpose of this study is to complish a method of fish glue malting with residual products such as fish head and skin discarded from sea food processing. Using the skins of Alaska pollack and file fish from fillet packers, the optimum conditions of skin glue processing were investigated and physical and chemical properties of the product were also determined. The yields of Alaska pollack, Thelagra calcogramma, skin and file fish, Novodon modestus, skin to the total body weight were $4.6\%\;and\;5.0\%$ respectively. The optimum conditions for a $49.3\%$n yield Alaska pollack skin glue processing were considered the extraction of previously tinted in $0.1\%$ calcium hydroxide solution for 3 hours with the additional water as much as 3 times of sample weight at $70^{\circ}C$ for 3 hours under the controlled pH 5.0. The conditions for file fish skin glue were similar to those of Alaska pollack except the addition of five times of water to the weight of sample skin needed for extraction. The content of crude protein of Alaska pollack and file fish skin glue were $98.0\%\;and\;96.0\%$ respectively. The contents of crude ash and crude lipid were not different from that of chemical grade gelatin. Relative viscosity, melting point, gelation temperature and jelly strength of Alaska pollack skin glue marked 5.84, $21.8^{\circ}C,\;7.1^{\circ}C\;and\;10.0g$ respectively and those of file fish skin glue showed $5.79,\;25.0^{\circ}C,\;7.4^{\circ}C\;and\;11.6g$ respectively.The color and turbidity of Alaska pollack skin glue are slightly superior to those of file fish skin glue. It is supposed that the extract residue of skin glue is valuable for use the animal feeds by the results of amino acid composition. And the ratio of each amino acid content to the total amino acid of Alaska pollack and file fish skin glue is similar to that of chemical grade gelatin.

• Investigative Magnetic Resonance Imaging
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• v.7 no.1
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• pp.39-46
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• 2003

Purpose : To develop a theoretical model for magnetic relaxation behavior of the superparamagnetic nano-particle agent, which demonstrates multi-functionality such as liver- and lymp node-specificity. Based on the developed model, the computer simulation was performed to clarify the relationship between relaxation time and the applied magnetic field strength. Materials and Methods : The ultrasmall superparamagnetic iron oxide (USPIO) was encapsulated with biocompatiable polymer, to develop a relaxation model based on outsphere mechanism, which was resulting from diffusion and/or electron spin fluctuation. In addition, Brillouin function was introduced to describe the full magnetization by considering the fact that the low-field approximation, which was adapted in paramagnetic case, is no longer valid. The developed model describes therefore the T1 and T2 relaxation behavior of superparamagnetic iron oxide both in low-field and in high-field. Based on our model, the computer simulation was performed to test the relaxation behavior of superparamagnetic contrast agent over various magnetic fields using MathCad (MathCad, U.S.A.), a symbolic computation software. Results : For T1 and T2 magnetic relaxation characteristics of ultrasmall superparamagnetic iron oxide, the theoretical model showed that at low field (<1.0 Mhz), $\tau_{S1}(\tau_{S2}$, in case of T2), which is a correlation time in spectral density function, plays a major role. This suggests that realignment of nano-magnetic particles is most important at low magnetic field. On the other hand, at high field, $\tau$, which is another correlation time in spectral density function, plays a major role. Since $\tau$ is closely related to particle size, this suggests that the difference in R1 and R2 over particle sizes, at high field, is resulting not from the realignment of particles but from the particle size itself. Within normal body temperature region, the temperature dependence of T1 and T2 relaxation time showed that there is no change in T1 and T2 relaxation times at high field. Especially, T1 showed less temperature dependence compared to T2. Conclusion : We developed a theoretical model of r magnetic relaxation behavior of ultrasmall superparamagnetic iron oxide (USPIO), which was reported to show clinical multi-functionality by utilizing physical properties of nano-magnetic particle. In addition, based on the developed model, the computer simulation was performed to investigate the relationship between relaxation time of USPIO and the applied magnetic field strength.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.10 no.1
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• pp.100-112
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• 2005

Soil temperature was measured from the surface to 40 cm depth at three stations with different heights in tidal flat of Gomso Bay, west coast of Korea, for one month in every season 2004 to examine the thermal structure and the variation. Mean temperature in surface layer was higher in summer and lower in winter than in lower layer, reflecting the seasonal variation of vertically propagating structure of temperature by heating and cooling from the tidal flat surface. Standard deviation of temperature decreased from the surface to lower layer. Periodic variations of solar radiation energy and tide mainly caused short term variation of soil temperature, which was also intermittently influenced by precipitation and wind. Time series analysis showed the power spectral energy peaks at the periods of 24, 12 and 8 hours, and the strongest peak appeared at 24 hour period. These peaks can be interpreted as temperature waves forced by variations of solar radiation, diurnal tide and interaction of both variations, respectively. EOF analysis showed that the first and the second modes resolved 96% of variation of vertical temperature structure. The first mode was interpreted as the heating antl cooling from tidal flat surface and the second mode as the effect of phase lag produced by temperature wave propagation in the soil. The phase of heat transfer by 24 hour period wave, analyzed by cross spectrum, showed that mean phase difference of the temperature wave increased almost linearly with the soil depth. The time lags by the phase difference from surface to 10, 20 and 40cm were 3.2,6.5 and 9.8 hours, respectively. Vertical thermal diffusivity of temperature wave of 24 hour period was estimated using one dimensional thermal diffusion model. Average diffusivity over the soil depths and seasons resulted in $0.70{\times}10^{-6}m^2/s$ at the middle station and $0.57{\times}10^{-6}m^2/s$ at the lowest station. The depth-averaged diffusivity was large in spring and small in summer and the seasonal mean diffusivity vertically increased from 2 cm to 10 cm and decreased from 10 cm to 40 cm. Thermal propagation speeds were estimated by $8.75{\times}10^{-4}cm/s,\;3.8{\times}10{-4}cm/s,\;and\;1.7{\times}10^{-4}cm/s$ from 2 cm to 10 cm, 20 cm and 40 cm, respectively, indicating the speed reduction with depth increasing from the surface.

• Journal of Korean Tunnelling and Underground Space Association
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• v.18 no.5
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• pp.401-412
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• 2016

It is extremely difficult to apply conventional grouting methods to subsea tunnelling construction in the high water pressure condition. In such a condition, the rapid artificial freezing method can be an alternative to grouting to form a watertight zone around freezing pipes. For a proper design of the artificial freezing method, the influence of salinity on the freezing process has to be considered. However, there are few domestic tunnel construction that adopted the artificial freezing method, and influential factors on the freezing of the soil are not clearly identified. In this paper, a series of laboratory experiments were performed to identify the physical characteristics of frozen soil. Thermal conductivity of the frozen and unfrozen soil samples was measured through the thermal sensor adopting transient hot-wire method. Moreover, a lab-scale freezing chamber was devised to simulate freezing process of silica sand with consideration of the salinity of pore-water. The temperature in the silica sand sample was measured during the freezing process to evaluate the effect of pore-water salinity on the frozen rate that is one of the key parameters in designing the artificial freezing method in subsea tunnelling. In case of unfrozen soil, the soil samples saturated with fresh water (salinity of 0%) and brine water (salinity of 3.5%) showed a similar value of thermal conductivity. However, the frozen soil sample saturated with brine water led to the thermal conductivity notably higher than that of fresh water, which corresponds to the fact that the freezing rate of brine water was greater than that of fresh water in the freezing chamber test.

• The Journal of the Petrological Society of Korea
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• v.10 no.2
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• pp.57-81
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• 2001

In the amphibolites of the Hwanggangri area, three metamorphic zones are established like hornblende-actinolite zone (H-AZ), hornblende zone (HZ) and diopside zone (DZ) by the main mineral assemblages. Hornblende zone and hornblende-actinolite zone develope away from the diopside zone that experienced the highest thermal effect. Thus, this pattern identifies the decreasing metamorphic grade of the contact metamorphism with increasing distance from the granitic pluton. The mineral assemblages of this rock are classified into six representative groups such as $\circled1$ actinolite+plagioclase+chlorite, $\circled2$ actinolite+hornblende+plagioclase+chlorite$\pm$epidote$\pm$biotite, $\circled3$ actinolite+hornblende+plagioclass$\pm$biotite$\pm$epidote, $\circled4$ hornblende+plagioclase$\pm$biotite$\pm$chlorite, $\circled5$ hornblende+plagioclase+diopside+actinolite$\pm$epidote$\pm$chlorite, $\circled6$hornblende+plagioclase+diopside$\pm$biotite$\pm$epidote. Two metamorphic events m recognized in the amphibolites of the study area that the first metamorphism is the regional metamorphism dominantly occurred in the whole Ogcheon metamorphic belt and it gave rise to the growth of actinolite at the core or center of the amphibole grains of coarse and medium size. Its metamorphic grade ranges from the greenschist facies to epidote-amphibolite facies. The second metamorphism overlapped is the contact metamorphism caused by the adjacent granitic pluton, and its metamorphic grade is thought to reach to the low pressure part of upper amphibolite facies. According to the calculation by TWEEQU thermobarometry and amphibole-plagioclase thermometry, the metamorphic temperature of initial regional metamorphism is $439-537^{\circ}C$ under pressure of 4.6-7.3 kb and its peak temperature and pressure are considered to reach to the range of 492-537 and 5.2-7.3 kb. And the temperature range of contact metamorphism occurred by intrusion of cretaceous granitic body, is $588-739^{\circ}C$ under pressure of 2.6-5.2 kb and its peak temperature and pressure are estimated as having the range of $697-739^{\circ}C$ and 3.8-5.2 kb that this amphibolites are estimated to pass through the metamorphic evolution of both the rise of temperature and the drop of pressure.

• Applied Chemistry for Engineering
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• v.10 no.4
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• pp.557-562
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• 1999

The reaction properties of Pd. Pd-Ce and Pd-La catalysts supported on ${\gamma}-Al_2O_3$ were investigated in the oxidation reaction of methane($CH_4$) exhausted from the compressed natural gas vehicle in a U-tube flow reactor with gas hourly space velocity of $72,000h^{-1}$. The catalysts were characterized by X-ray diffraction(XRD), X-ray photoelectron spectroscopy(XPS), BET surface area and hydrogen chemisorption. Pd catalyst prepared by $Pd(NO_3)_2$ as a palladium precursor and calcined at $600^{\circ}C$ showed the highest activity for a methane oxidation. Catalytic activity of calcined $Pd/{\gamma}-Al_2O_3$ in which most of palladium was converted into palladium oxide species was higher than that of reduced $Pd/{\gamma}-Al_2O_3$ in which most of palladium existed in palladium metal by XRD. As increasing the number of reaction cycles in the wide range of redox, the catalytic activity of $Pd/{\gamma}-Al_2O_3$ was decreased and the highly active window became narrower. Lanthanum oxide promoted Pd catalyst, $Pd/La/{\gamma}-Al_2O_3$ showed enhanced thermal stability compared with $Pd/{\gamma}-Al_2O_3$ even after aging at $1000^{\circ}C$, which was ascribed to the role of La as a promoter to suppress the sintering of palladium metal and ${\gamma}-Al_2O_3$ support. Almost all of methane was removed by the reaction with NO at the redox ratio of 1.2 in case of oxygen excluded steam, but that activity was significantly decreased in the steam containing oxygen.